The Athlete's Heart Blog

Cardiac Arrest During Long-Distance Running Races: A New Report

2012-01-17T11:37:00.000-08:00

This past week, the results from an important study on the heart risks of long-distance running was reported in the New England Journal of Medicine.

A group of investigators from Boston looked at the experience of ~11 million runners who took part in half marathon or full marathon races in the United States between 2000 and 2010. This is the largest study of its kind ever undertaken.

The important findings were:

-59 athletes had cardiac arrest and 42 of those died

-For marathon runners the risk of cardiac arrest was 1.01 per 100,000 participants

-For half marathon runners the risk of cardiac arrest was 0.27 per 100,000 participants

-The risk for men was several-fold greater than for women

-The majority of deaths occurred during the last 6 miles of the marathon or the last 3 miles of the half marathon

-From medical records, the cause of cardiac arrest could be determined for 31 victims (23 of whom died). In most of the cases where the athlete died, there was a specific heart condition that was responsible:

---Hypertrophic cardiomyopathy (HOCM) in 8

---Possible HOCM in 7

---Hyperthermia in 1

---Arrhythmogenic right ventricular cardiomyopathy in 1

---Hyponatremia in 2

---No specific cause in 4

Some important, NEW observations were:

--The frequency of cardiac arrest is extremely low....and even lower than previously thought.

--The survival rate from cardiac arrest was surprisingly good, at 29%. This is much higher than previous reports for out-of-hospital cardiac arrest. It suggests that bystander CPR and early defibrillation may be readily available at race venues.

--The risk is greater in marathons, compared to half marathons. The reason(s) are not yet clear.

This new report provides the most comprehensive information yet on cardiac arrest during running races. Athletes should be encouraged by the extremely low rate of cardiac arrest and with the favorable survival rates reported. Athletes should also take note that the cause of cardiac arrest was most often due to an underlying cardiac condition that might be discoverable BEFORE participating in a traning program or race. It's reasonable to conclude that a pre-participation visit to the doctor for a careful physical examination and, potentially, cardiac testing might reduce an athlete's chances of being a victim.

Race Safety and USA Triathlon

2012-01-16T18:53:00.000-08:00

I had the chance to attend the annual USA Triathlon Race Director's Symposium this weekend in Colorado Springs.

Along with Stuart Weiss, MD (medical director of the ING NY Marathon. NY City Triathlon, and upcoming Ironman New York triathlon), Richard Miller, MD (a trauma surgeon at Vanderbilt University), Bob Burnett (a New England race director), and Robert Vigorito (a mid-Atlantic race director), I'm serving on a Medical Review Panel convened by USAT to review the experience with race-related fatalities over the past decade and to offer recommendations about improving race safety going forward.

We've had a chance to review preliminary information about race-related fatalities from 2003-2011 and I was asked to present some information to about 80 race directors from across the country who were attending the Symposium.

Some Preliminary Information about Triathlon Fatalities

A snapshot of event-related fatalities at USAT-sanctioned events:
-44 athlete fatalities, including 5 traumatic deaths and 39 non-traumatic deaths
-All 5 traumatic deaths occured with bicycle crashes
-Most (and, conceivably all) of the non-traumatic deaths were due to sudden cardiac death (SCD)
-The majority of the non-traumatic deaths occurred in the swim leg of a race, but there were also deaths in the bicycle and running legs....and 2 deaths that occurred after athletes had completed a race and left the race venue
-Deaths occurred in athletes in nearly every age group
-Deaths occurred in races of every distance from short sprint to Ironman distance

Some Information about Sudden Cardiac Death (SCD)

I shared some general information about SCD, describing reports from 2011 on NCAA athletes and on the French general population:

-In NCAA athletes, the incidence of SCD is 1 per 43,770 athletes per year
-Basketball and swimming appear to have the highest risk

-In the French general population, the risk of SCD is 4.6 cases per 1,000,000 population per year
-Deaths were noted in nearly every conceivable sporting activity
-Deaths were noted in individuals from 11 years old to 70+ years old
-Extrapolated to the U.S. population, there should be 4000+ fatalities in the U.S. due to SCD each year

Feedback from the Attendees

I had a chance to hear from the race director attendees about many relevant experiences. Indeed, several of the race directors who were present had firsthand knowledge about some of the fatalities.

Race directors from Utah were able to share with the audience their approach to dealing with the aftermath of such a fatality--from sharing information at the race venue, to working with family members of the victim, to working with the medical and EMS crews who attended to the victim.

There were many suggestions about how we might work to reduce the number of fatalities:

-Easier access to AED's, including deploying an AED on a boat so that CPR and defibrillation might occur earlier in the event of a swim leg event
-Reducing anxiety among swimmers before the race. Attendees noted that the NYC Triathlon already employs psychologists to conduct pre-race briefings where coping strategies are discussed
-Wearing inflatable devices during a swim which could be deployed if/when a swimmer experienced difficulties
-Designing swim courses to limit the distance from shore
-Having pre-established action plans for the specific possibility of SCD during the swim

One particularly heart-warming story came from a young race director who shared his personal story of having SCD at the swimming pool in 2010, receiving 14 minutes of CPR, and being resuscitated successfully. He now has an internal defibrillator and is working through the issues of how active he can continue to be. He's continuing his passion for triathlon by serving now as a race director.

A Visit to USAT's Offices

On the last evening of the Symposium, we visited the offices of USAT for supper and some fellowship. I was totally fascinated by the many photographs and memorabilia on the walls of the office. The highlights were photographs of the Olympic triathlon teams from the 2000, 2004, and 2008 Olympic Games. Really inspiring.

Ahead

Our Review Panel's work will continue in the coming weeks as we work to understand more about the athletes who died and about the circumstances surrounding their deaths. I'm optimistic that when we're finished with our review, we'll be able to offer some useful advice to USAT and some information to the endurance sport community at large. I'll keep you posted.

I'd be happy to receive comments and suggestions from the readers here about how we might improve race safety.

Cardiacathletes.com: An Online Patient Support Community

2011-12-20T07:54:00.000-08:00

I've been aware of an online patient support community called Cardiac Athletes for a while now. I got an email yesterday from Lars Andrews, their chief cardiac physiologist asking if I'd spread the word about their site.

Taking a look, the site brings together athletes from around the world with various heart conditions. There is some general information that will be useful to athlete patients, but the biggest opportunity here is the Forum, where athletes can connect with each other about their medical conditions.

So check out www.cardiacathletes.com.

Viagra: Does it Improve Athletic Performance?

2011-12-19T08:13:00.000-08:00

My friend, Scott, used Twitter to ask me about Viagra a couple weeks ago. He was riding on his trainer and saw an advertisement on the TV about Viagra....and he was wondering if it could enhance his athletic performance.

Here's what I've learned....

Introduced in 1998, Viagra is one of the trade names for the compound, sildenafil citrate. Manufactured by Pfizer, this drug is used primarily to treat erectile dysfunction (ED), but it has also found niche uses as well for the treatment of pulmonary arterial hypertension (PAH, high blood pressure in the lungs) and altitude sickness. Viagra is similar in properties to both Cialis (tadalafil) and Levitra (vardenafil).

By inhibiting an enzyme in the penis called cGMP-specific phosphodiesterase type 5, Viagra actgs by increasing bloodflow that produces an erection. We call drugs like Viagra vasodilators because they dilate the blood vessels. It's taken in a pill form, at a dosage of 25 - 100 mg, and is recommended for use not more than once per day, sometime between 30 minutes to 4 hours prior to sexual intercourse.

But if Viagra can produce greater bloodflow in the penis, could it also produce increased bloodflow elsewhere in the body? And, as a result, might it lead to increased oxygen delivery to the muscles in a way that could enhance athletic performance?

Interestingly, we learned during the Balco investigation that many professional baseball players and other athletes were using Viagra as an on-field performance-enhancing agent. In fact, in 2008 Victor Balco claimed that the use of Viagra was even more common than the use of creatine.

The science about Viagra and athletic performance is actually very sparse.

Interest in this regard was stimulated by a study of 14 mountaineers and trekkers by a group of investigators at the University of Giessen in 2004 [1]. They studied the athletes using a cycling test at near sea level (in Giessen), with a reduced-oxygen environment, and again at Mt. Everest Base Camp (5245 m). They found that Viagra increased the maximum workload in each setting and concluded that "sildenafil is the first drug shown to increase exercise capacity during severe hypoxia both at sea level and at high altitude."

There's been just 1 other study in humans to show a direct benefit of Viagra on athletic performance [2]. A group of investigators from Stanford hypothesized that Viagra would improve the cardiac output (CO), arterial oxygen saturation (PaO2), and performance at altitude (relatively low oxygen environment), but would have no effect at sea level (with a normal level of atmospheric oxygen). They studied 10 cyclists with a 10 km time trial (TT) at both sea level and simulated high altitude (3874 m). At sea level, Viagra had no effect on the outcome measures. At altitude, Viagra produced higher CO, higher PaO2, and a 15% improvement in time for the 10 km TT. On review, though, the investigators found that there were actually 2 subgroups: a group of Viagra responders, who improved their TT performance by 39% and a group of non-responders who improved their TT performance by only 1% (which was not statistically significant). The authors concluded that Viagra can greatly improve cardiovascular function and performance in a low-oxygen environment for certain individuals.

But, of course typical athletes don't compete at altitudes of 2+ miles!

The issue of whether Viagra might affect athletic performance drew the world's attention heading into the Beijing Olympic games in 2008. In assembling its list of banned substances for 2008, the World Anti-Doping Agency (WADA) wrote:

"As regards sildenafil (Viagra), WADA is aware of studies presented in relation to the potential of sildenafil to restore pulmonary capacities at very high altitudes. WADA is currently funding a number of research projects on the effects of sildenafil at various altitudes. These projects are ongoing."

Indeed, Viagra has not yet been added to the WADA list of banned substances.

In summary, then, Viagra is useful for the treatment of ED and PAH. Although there is some evidence of performance-enhancing effects on athletic performance (in some individuals) at altitude, there is no evidence that Viagra improves performance in typical athletic activities.

References:

1. Ghofrani HA, Reichenberger F, Kohstall MG, et al. Sildenafil increased exercise capacity during hypoxia at low altitudes and at Mount Everest Base Camp. Ann Int Med 2004; 141:169-177.

2. Hsu A, Bamholt KE, Grundmann NK, et al. Sildenafil improves cardiac output and exercise performance during acute hypoxia, but not normoxia. J Appl Physiol 2006; 100:2031-2034.

Athletes and Compression Garments

2011-10-20T14:36:00.001-07:00

My column this month at Endurance Corner is entitled, "Everything I Know (and Don't Know) About Compression Garments." It's broken into part 1 and part 2 postings.

In the multisport world, compression garments have become very popular over the past few years. I review some of the studies on compression garments and athletic performance, recovery, long distance travel, and the heart specifically.

A Book Recommendation

2011-10-11T11:13:00.000-07:00

Cuppett M and Walsh KM. General Medical Conditions in the Athlete, 2nd Edition. St. Louis: Elsevier Mosby, 2012.

I came across this book and thought that I'd take a minute to offer my recommendation here at the blog.

This 2nd edition is written by two athletic trainer educators--one at the University of South Florida and the other at East Carolina University. It's a textbook aimed at athletic trainer students that covers gammut of health issues that confront athletes of all sorts. There are chapters devoted to diagnostic imaging and testing, pharmacology and drugs, common bedside procedures, and to medical conditions that affect each of the body's systems.

Although the book is aimed at health profession students, it's written at a level and in a style that make it accessible to athletes themselves. By far, it's the best single book I've seen that is devoted to medical conditions in athletes and could serve as a great home reference book.

How to Find a Doctor (for Athletes)

2011-09-20T12:15:00.000-07:00

I've received a couple questions this past week about "how to find a doctor." In my area. One who understands athletes. One who will take me seriously. And so forth.

I've said on many occasions that adult athletes would be well served by having a primary care physician--one that they could visit annually for a physical examination and then rely upon when health issues arise. Some ideal charateristics of that doctor might be:

1. Located in your community or not too far away.

2. An athlete himself or herself....or at least "athlete-friendly" and "athlete-knowledgable."

3. Accessible....at the office, but also potentially by phone or email.

4. A good listener.

5. Responsive to your needs.

6. Understandable, especially when explaining medical issues to you.

7. Familiar with medical specialists in your community, if their services are needed.

But how do you find that person? Here are some suggestions:

1. Ask you athlete friends who they see (and like). This is your best bet. Find a fellow cyclist or runner who happens to be a physician....and ask him/her who they'd recommend.

2. If you've seen some sort of healthcare professional recently, such as a physical therapist, chiropracter, or orthopedic surgeon, ask who they might recommend.

3. Call your local medical society and ask for a recommendation. Explain what you're looking for. They should be able to help.

4. If you live near a medical school, call the school's sports medicine department and ask who they might recommend.

Those are my best ideas. Maybe the readers can offer some other suggestions. If so, please leave a comment below.

Do Cyclists (and perhaps Triathletes) Live Longer?

2011-09-16T13:34:00.001-07:00

Check out my monthly column at Endurance Corner. This month I describe some recent studies about endurance athletes and longevity.

Ironman and Heart Health: My Take on Things

2011-09-15T11:16:00.000-07:00

For those of you who don't already know him, let me introduce you to Dr. John Mandrola. You can read his musings at his Dr. John M Blog and follow along with his Twitter feed. John is a cardiologist in Lexington, Kentucky, who specializes in electrophysiology; he takes care of patients who have all sorts of abnormal heart rhythms, offering diagnosis and the entire spectrum of treatments available to these patients. He's also a competitive cyclist and, at some point, was a triathlete, as well.

I particularly enjoy reading his Cycling Wednesday blog posts that are usually devoted to the "intersection" of medicine and cycling. These posts would be recommended reading for most athletes regardless of their sport. What I enjoy most about these blog posts are John's skill at human observation, his ability and willingness to describe our follies (both physicians' and athletes'), and his seeming general skepticism about many things. We often see things the same way.

The week before last, Dr. John wrote a blog piece entitled, "Is the Ironman triathlon heart-healthy?" Needless to say, this caught my eye. And, judging from the many comments I received afterwards, it caught the eye of a good many other triathletes as well. I also saw that there was a lively discussion on the Slowtwitch forum, with many triathletes weighing in on Dr. John's thoughts and offering some personal accounts of various heart ailments as well. I also see that Dr. John received many replies and comments at his blog and felt obliged to issue "An Iron response...." at his blog a couple days after the original post.

Dr. John offered some important thoughts about endurance training and racing and their impact on heart health. These issues are important. His blog piece contained both opinion and fact. And, while it might be easy for me (as another medical professional) to see the difference, I can tell that many readers weren't able to make that distinction. They got upset about some of the opinions and lost track of the facts. I thought I'd take a moment to separate out the opinions and facts--at least, as I see them--so that our readers might be in the best possible position to draw their own conclusions.

DR. JOHN's OPINIONS

1. Ironman is the pinnacle of triathlon. No doubt, some people hold this opinion, but I'll bet that many triathletes don't. Olympic-distance (draft legal) racing is probably also a contender for being the pinnacle of our sport in many people's eyes.

The participation rate for Ironman distance triathlon is relatively small. With about 25 Ironman-branded races worldwide each year and some number of other races of iron distance, the number of participants each year worldwide is probably less than 75,000. To put that into perspective, USA Triathlon recently reported that in the United States alone, there were 2.3 million triathlon participants in 2010. I've raced in 6 Ironman races over the past few years and each of those races held a pre-race dinner a couple nights before the race. At each of those dinners, 40-50% of the crowd stood up when the first-timers were introduced. With that statistic, it's obvious that many Ironman participants are "one-and-done."

2. Ironman triathlon....I don't get it. Sure. Not everybody "gets it." I could say the same for golf or tennis. To each, his own.

3. Heart healthier ideas: marathon or shorter running race, bicycle racing, shorter-than-Ironman triathlon. There is ample evidence that aerobic exercise produces long-lasting health benefits, including a longer life-expectancy. There has been speculation that, beyond some amount or intensity of exercise (or a combination of both), there might be some harm, including injury to the heart. I'm not aware of any credible studies, though, that address this issue in terms of the relative safety of 1 endurance sport over another....or race competition of 1 distance over another. In my view, it's hard to imagine that half marathoners are somehow "heart healthier" than marathoners....or that half Ironman triathletes are somehow "heart healthier" than full Ironman triathletes. This issue about some threshold for harm remains unstudied....and therefore unsettled.

4. Can't imagine riding for 5 hours continuously at 200 Watts. Obviously opinion. For me, it would be nearly 6 hours at 180 Watts. But BTW, I'm always willing to stop for a cookie break....on a training day OR at the race!

5. Long-term, low-intensity, ultra-endurance exercise (slogging, not racing) isn't heart-healthy. Opinion. We know that long-term, low-intensity exercise IS heart-healthy. I'm not sure what qualifies for "ultra-endurance" and I'm not sure that "slogging" vs. "racing" makes a difference for the heart. Again, this issue simply hasn't been studied.

6. The occurrence of fatalities during Ironman triathlong might entice others to participate. Perhaps. I suppose anything is possible, but I haven't encountered that motivation. It's important to remember that the small number of fatalities at triathlon races have occurred in races of all distances and the victims have spanned a large age range and ability level--from novice to veteran triathlete. In truth, most triathlon race fatalities have occurred in shorter-than-Ironman races.

THE IMPORTANT FACTS

1. Ironman triathletes are focused. True. Regardless of the particular hobby, anybody who spends 10-20 hours per week doing something is focused.

2. Daily exercise is good. Irrefutable fact.

3. Athletes are more likely to die of sudden cardiac death (SCD) during exercise (or competition) than non-athletes (who don't exercise). Fact. SCD is not related solely to triathlon, though. A recent study of SCD in the general adult population showed that this occurs in (decreasing order of incidence) cycling, jogging, soccer, hiking, swimming, basketball, rugby, tennis, diving, judo, handball, alpine skiing, table tennis, and body building, among other sports. Cycling accounted for almost one third of the SCD events. Although most of the triathlon race-related deaths have occurred during the swim portion of the race, in the general population SCD while swimming accounts for only about 4% of the total number of episodes. On balance, though, the health benefits of exercise appear to far outweigh the small risk of SCD.

4. Endurance athletes are more likely than non-athletes to develop atrial arrhythmias. Fact. There is overwhelming evidence for this. Many references are included in Dr. John's second blog post. This issue hasn't been well studied in triathletes, but there's no reason to think that triathletes are immune. The influences of exercise duration and/or intensity on the development of these arrhythmias need further study.

5. Scarring in the heart has been found in long-term endurance athletes (and laboratory rats). True. I wrote about the recent studies in a column at Endurance Corner. It's important to remember, though, that scarring was only found in veterans of many, many marathons....and the clinical significance (if any) has not yet been determined. For now, there is no evidence that the scarring led to a shorter life or was associated with other heart problems in these runners, but these observations merit further study.

6. Heart damage can be detected after an endurance race. True. Studies have shown elevated levels of cardiac enzymes (indicating heart cell damage) in the bloodstream and altered (diminished) heart function by echocardiogram in athletes immediately after running and triathlon events. These abnormalities have not been shown to persist and so their significance (if any) is not clear. Some authorities have speculated that repeated episodes may be harmful.

ONE UNTRUTH

1. Sudden cardiac death (SCD) is "not uncommon" during triathlons. This simply isn't true. SCD is actually a rare event at triathlons. There is a single report on this issue that showed SCD to occur at a rate of approximately 1 per 65,000 participants. USA Triathlon is convening a Taskforce to examine this issue in further detail and I'm certain that additional information may be reported in the coming months. To give this issue some context, it was reported earlier this year that the rate of SCD among NCAA athletes (in all sports) was approximately 1 per 45,000 athletes per year.

DR. JOHN's SUGGESTED ACTIVITIES

Let me finish by saying that Dr. John's list of 7 suggested activities at the end of his first blog piece are great ideas. I need to work on #2, #3, and #6. I'll report back.

1. Swim a fast and smooth 400-yard individual medley (100 yards each of the butterfly, back, breast, and freestyle strokes

2. Ride a criterium bicycle race

3. Train to knock 1 minute off your best 10 km run time

4. Complete an Olympic-distance triathlon

5. Try touching your toes without bending at the knees

6. Write a blog without a grammatical error

7. Sit still long enough to read a book

Recent Triathlon Deaths

2011-08-29T16:21:00.000-07:00

In news reports yesterday, I read about the sad news of a triathlete who died during the swim portion of the Ironman Louisville triathlon over the weekend. This death comes just a month or so after the highly publicized deaths of 2 triathletes during the New York City Triathlon. It's been a while since I've written about the issue of sudden cardiac death during triathlons, so I thought I'd share some thoughts.

There has still been little reporting about the tragic event at the Louisville race, but I've learned that a 46 year old man was pulled from the water a little more than 300 yards from the start of the triathlon and brought back to the start area to receive further care. Authorities said that he had suffered cardiac death (SCD), was taken to the Louisville's University Hospital, and was pronounced dead there. I've read that an autopsy was performed, but the findings have not been released.

At last month's New York City Triathon, 2 athletes suffered SCD. One athlete, a 64 year old man died on the day of the event and a 40 year old woman was apparently resuscitated but died a short time later. These deaths attracted a lot of attention in the popular press and I had the opportunity to share some of my thoughts in an article entitled "Why is the Swim the Most Deadly Leg of the Triathlon?" that appeared in the Wall Street Journal. The swim portion of that triathlon was particularly rough and many athletes had to be rescued. Some observers raised questions about conducting the race in those conditions and about the quantity and availability of on-water support to rescue swimmers who weren't capable enough to complete the swim. I must say, though, that the event organizers are very experienced with directing large triathlons and there appeared to be a robust water safety plan....at least from afar. I was also contacted by The Weather Channel which wanted information and an opinion about how the weather--including water temperature and current--might have played a role in the athletes' deaths. Again, I suspect this wasn't a big a factor.

The unfortunate truth is that a small number of athletes will suffer SCD during training or competition....and this is true regardless of the sport. I've written previously in a column at Endurance Corner about a recent study by Dr. Kevin Harris of fatalities during triathlon events. In a study of all of the USA Triathlon (USAT) sanctioned events during a 3-year period in the United States, he identified 14 triathletes who died. I recently read in a notice from USAT that nearly 2.3 million individuals completed a triathlon in 2010 in the United States, so you can see how rare an event a race-related fatality really is. Interestingly and importantly, in almost all triathlon fatalities, the victim died during the swim portion of the event and the cause was almost always cardiac-related.

I've read through the many discussion threads on this issue at Slowtwitch and other forums and there are obviously many opinions....and many unanswered questions. I think that most of us in the triathlon community could agree that it would be great to prevent some or all of these fatalities, if it were possible. But how?

As I see it, there are only a couple possible ways:

1. Identify victimis of SCD more quickly and provide better and faster medical care so that there might be more survivors.

and/or

2. Ensure that, before participating, athletes learn about any heart conditions they might have....and receive necessary treatment and counseling about participating.

USAT Task Force

The week before last I received an email from Rob Urbach, the CEO of USA Triathlon. In that email to USAT Race Directors, he paid special attention to the recent deaths during the New York City Triathlon and indicated that USAT would be convening a taskforce to look at the issue of fatalities during triathlon events. This is a tremendously worthwhile pursuit. I hope that USAT can assemble a group of experts representing the triathlon, medical, and other relevant communities and make a careful assessment of the information that is available about these events. I think this group should:

1. Review the fatalities to look not only for causes of death but also pre-existing medical conditions that might predispose the athlete to sudden cardiac death.

2. Make a careful review of the experience in other endurance (or other) sports (both in and out-of-competition), to place the triathlon statistics into proper perspective.

3. Evaluate the race-day safety resources that are in place to deal with athletes who might suffer sudden cardiac arrest. It is extraordinarily difficult to tend to the victim of SCD in/on the water and we know that CPR and early defibrillation (with just a few minutes) is needed for victims to survive. I'm not aware of any athlete survivors of in-water SCD at a triathlon.

4. Consider what warnings should be issued to participants in terms of the risk of competing and what role that organizers should play (if any) in ensuring the physical ability and medical health of the participants.

As we await the work of the task force, I'd make the following suggestions:

1. For race directors and event organizers. Carefully and critically evaluate your safety plan as it relates to victims of SCD, particularly during the swim. Consider the communication system(s) that are available to water safety personnel and the plans for early CPR and defibrillation should they be needed.

2. For athletes. Realize that there is some small risk of SCD during a race. You should consult with your physician about your particular risk and what, if anything, can be done to reduce that risk. Most athletes would be well served by visiting with a physician for a careful medical history and physical examination that is focused on heart-related problems. Make certain that your overall and heart health are in order before training and competing.

3. For doctors. Become knowledgable about the heart problems that face athletes and be ready to offer sound advice to your athlete patients.

4. For the press. Always give some context for reports on sports-related deaths. Remind your audiences that these events are rare and that exercise provides many proven benefits in spite of any small risk of race-related SCD.

In the Medical News: Sports-Related Sudden Death in the General Population

2011-07-29T07:52:00.000-07:00

In a scientific article published online earlier this week by Circulation, Eloi Marijon and colleagues at the Paris Cardiovascular Center reported on "Sports-Related Sudden Death in the General Population."

In recent years there has been a focus on sudden cardiac death (SCD) that occurs in young athletes who are participants in organized and/or competitive sports. There has been much less attention paid to SCD that occurs in athletes (of all ages) who are not part of organized or competitive sports--those who are undertaking so-called recreational sporting activities. The investigators have studied the issue of SCD in this second, much larger group of athletes.

This large, observational study examined the experience in France between 2005 and 2010. The experience included 169,742,000 age specific person-years of follow-up. The investigators considered 2 separate groups:

1. Young athletes, ages 10-35, who were competitive athletes, and

2. Athletes, ages 10-75, who were participants in recreational sporting activities (cycling, jogging, soccer, hiking, swimming, basketball, and others).

Overall, the incidence of SCD was 4.6 per million population per year (860 events total). While a small number of SCD events (50) were observed in the first group, approximately 94% of the SCD events occurred in the group of recreational athletes. If the same statistics were applied to the United States population, we might expect upwards of 4250 cases of SCD among recreational athletes each year.

In the group of recreational athletes with SCD, only 11.7% had a known history of cardiovascular disease or had more than 1 classic risk factor for coronary heart disease. The majority of victims in this group were regular exercisers.

The exact cause of death among the victims was determined for only a minority (24.7%) of the group. If a cause of death was identified, it was cardiac-related in 98%.

The vast majority (93%) of SCD events were witnessed, but bystander CPR was provided in only one third of cases. Survival among the athletes with SCD was very much dependent upon prompt CPR and defibrillation.

SUMMARY

The frequency of SCD among recreational athletes is probably much higher than previously thought. This issue deserves and probably will receive additional investigation. The information provided by this report should prompt or renew discussion about the availability of CPR and defibrillation (AED's) at venues where recreational athletes participate in their sports.

Normann Stadler, Heart Surgery, and You

2011-07-27T19:30:00.000-07:00

In my monthly column at Endurance Corner, I write about Normann Stadler, the 2-time Ironman World Champion who recently underwent urgent heart surgery. He's making a good recovery early after operation.

I share my thoughts about how heart disease affects even the fittest athletes. The lesson in Stadler's story is to take charge of your own cardiovascular health.

In the Medical Journals: Athlete's Heart and Cardiovasclar Care of the Athlete

2011-06-23T11:23:00.001-07:00

In last week's edition of the American Heart Association's (AHA) medical journal, Circulation, Aaron Baggish and Malissa Wood contributed a review article entitled, "Athlete's Heart and Cardiovascular Care of the Athlete: Scientific and Clinical Update." This is the most concise, current review of this topic I have seen and I would recommend this article to those of you with a medical or physiology background.

Over time, I'll try to put up some posts here at the blog that cover, in layman's terms, some of the important topics covered in this article.

Gyorgy Kolonics, Sprint Canoer, 1972-2008

2011-06-21T08:35:00.000-07:00

I recently came across the story of Olympic canoer, Gyorgy Kolonics and I thought I'd share the ir with you here. I've written previously about the importance of bystander CPR and availability of AED's at sporting events. We can't rewrite history, but we might wonder if the outcome might have been different if an AED had been available for Gyorgy Kolonics.

Kolonics was a sprint canoer from Hungary who had reached the top of his sport by the 1992 Olympics in Barcelona, where he finished 5th and 7th in the C-2 500 m and 1000 m events. In the following several years, he would go on to win a total of 11 world championships gold medals. At the 1996 Olympics in Atlanta, he won a gold and a silver medal in the C-2 events. At the 2000 Olympics in Sydney, he won a gold medal in the 500 m C-1 event and at the 2004 Athens Olympics he won a bronze medal in the 1000 m C-2 event.

Kolonics died in his mid-30's on July 15, 2008 in Budapest, Hungary, while he was on the water training. He collapsed suddenly and was taken to shore, where his coach and teammates tried to resuscitate him. No AED was available. Accounts of his death estimate that an ambulance arrived on the scene nearly 40 minutes after he collapsed and there was some controversy about the skills of the responding ambulance personnel. Indeed, Kolonics could not be resuscitated and he died on the scene.

An autopsy was performed, but the only heart-related finding was some mild plaque in the coronary arteries. Authorities concluded that he had a sudden cardiac death (due, presumably, to a ventricular arrhythmia).

As I've pointed out previously, all of us in the athletic community would be well served by learning CPR and the use of an AED. When an athlete collapses from a sudden arrhythmia, his fate rests entirely in the response by the bystanders. The Gyorgy Kolonics story also illustrates the importance for coaching staffs and event organizers to have plans for AED or EMS availability within short response times.

Six Tips for Athletes to Reduce the Cost of Preventive Medical Care

2011-06-07T10:24:00.000-07:00

Readers here at the blog will know that I've recommended that adult athletes have a doctor....and that they visit the doctor annually. This sort of medical care falls under the category of preventive care or wellness care. You'll also know that I've recommended cardiac screening evaluations that might include an ECG or echocardiogram.

When I talk to athletes about this issue, it seems that one of the most common barriers is the cost. No doubt, medical care is expensive. Moreover, many young adult athletes have medical insurance plans with high deductibles....or no medical insurance coverage at all.

My friend and professional triathlete, Jusitn Daerr, recently wrote an article entitled, "I'm Young, I'm Fit, What Could Happen?" at EnduranceCorner about his experience with a new-patient office visit and cardiac screening evaluation. I'd encourage you to read his piece. His situation and thoughts are typical for young adult athletes.

Today, I thought I'd offer 6 tips for athletes to help reduce the expense of preventive medical care:

1. Know the price (as best you can)

It may actually be difficult to know (ahead of time) the cost of medical services you might need, but it's worth your effort to try to find out. Your doctor's office can readily tell you the typical charges for a new patient or established patient visit. Keep in mind that a follow-up visit often costs much less because the doctor doesn't need to spend as much time getting to know you after the initial visit. You might feel reluctant talking to the doctor about the costs of any visit, but he/she will probably be very happy to answer questions that you might have.

Your doctor or his/her office staff should also be able to find for you the costs for any laboratory or other diagnostic testing that is recommended. It's important to realize that your doctor may establish the fee schedule if the test is done in his/her office, but won't have any part in setting the charges if the test(s) are performed at a hospital or other facility. Nevertheless, the doctor's staff can help you track down the costs of most any test that is recommended.

Your doctor and his/her office staff can also provide some "local knowledge" about options for where to go for a particular test. Since each facility will have a different fee schedule, it can pay off to do some research about the charges at different facilities that offer the test(s) that you need. Don't be afraid to ask.

2. Time your medical care to your advantage

By its very nature, preventive care is not urgent or emergent. Office visits and laboratory or other diagnostic testing can be scheduled at your convenience. You should take advantage of that opportunity.

Many athletes will have a medical insurance plan with an annual deductibe....a dollar amount that you must pay fully out of pocket before the "real" insurance coverage kicks in. In recent years, it has become common for plans to have deductible amounts of $500 to $1000 or more. Since preventive care often costs far less than this amount, the cost of that preventive care is often totally out-of-pocket.

If you are somebody who has various medical expenses throughout the year (that add up over time), be sure to schedule your preventive care at a time during the year when you will get the best insurance coverage. This could mean delaying that care until later in the year, once your annual deductible is already met. By doing this, you might enjoy considerable cost savings for your preventive care needs.

3. Find health fairs that offer needed services

Local health fairs are a great oportunity to find some of the preventive services you need....either FREE or at a greatly reduced price. But you have to be willing to do some homework to find these health fairs....and work with your doctor to plan for using the health fairs to get needed test(s).

Justin Daerr brought to my attention a great offering in the Colorado front range area. There is a multi-city, continuing health fair sponsored by 9News. Examples of services that can be obtained at a tremendous cost saings include: blood chemistry (blood tests), blood counts (blood test), blood pressure, bone health screening, breast exam, eye health screening, diabetes screening (fingerstick), hearing tests, lung function test, pap smear, sleep apnea screening, and many others. With a variety of offerings, you could choose WHEN and WHERE to get any needed screening tests....and the results could be forwarded to your doctor for review.

This is just one example. Your doctor's office can often help you to locate suitable offerings in your area. Keep in mind, too, that in February, during Heart Month, many health organizations sponsor health fairs that are very specific to the heart and cardiovascular systems. It's often possible to find fairs that offer free ECG's, heart exams, and exams/testing for peripheral arterial disease of the extremities and neck. It's not usunual to be able to get $100's to $1000+ of free services if you plan ahead.

4. Use your HSA if you have a high-deductible medical insurance plan

By law, individuals with high-deductible medical insurance plans may contribute pre-tax dollars (up to $3,050 for an individual in 2011) to a Health Savings Account (HSA) that can then be used to pay for necessary medical expenses. By planning ahead for your preventive care needs, you could make the necessary contribution to your HSA and pay for your preventive care with pre-tax dollars (getting you a "discount" of whatever your tax rate would ordinarily be).

Since preventive care can typically be an out-of-pocket expense, the use of your HSA for this purpose is a no-brainer.

5. Use your employer-based flexible spending account if it's available

Many large employers offer a flexible spending account as part of their benefits package. Like an HSA, the flexible spending account allows for contribution to the account of pre-tax dollars that are deducted from your paycheck each pay period. The money accumulates in your account until you spend it on qualified expenses. Virtually all preventive medical care and any diagnostic testing recommended by your doctor would be eligible.

Unlike the HSA, however, money in the flexible spending account "goes away" if it is not spent by the end of each calendar year (plus, perhaps a small grace period). As a result, it requires special attention and forethought on your part to make an appropriate contribution choice....and then to spend the money before the end of the year. Even with these burdens, though, the flexible spending account is a terrific way to pay for your preventive care needs with pre-tax dollars (getting you a "discount" of whatever your tax rate might be).

6. Take advantage of wellness benefits of your insurance plan

Lastly, be aware that many employer-based health insurance plans offer some sort of wellness benefit. With the newly passed health care reform package, these wellness benefits will be more and more common in insurance plans, going forward.

As an example, I'll share some of the details of the wellness benefit offered through my own personal employer-based Blue Cross insurance plan. If I enroll (by answering an online questionnaire at the start of the year), I can get up to $1000 in covered wellness services without paying a cent out-of-pocket. The plan prescribes the eligible, covered services by age group for the plan's participants.

I hope that these 6 suggestions are helpful. A little bit of knowledge can help an athlete get the most for their health care dollar!

You Could Be the Hero!

2011-06-07T10:21:00.001-07:00

Check out my monthly column at EnduranceCorner. Celebrating national CPR week, I urged athletes to learn CPR and use of an automatic external defibrillator (AED). We're all safer if our athlete friends know these lifesaving techniques.

Useful Website: Recipe Blog

2011-04-26T11:25:00.000-07:00

I've gotten several inquiries lately about (heart) healthy eating for athletes, asking about print or online resources for additional information.

I thought I'd draw your attention to a terrific online resource....the blog of my friend, Vince Matteo. You'll see that he writes creatively about a variety of triathlon-related topics, but you should check out the "What's for Dinner?" section, where he keeps what he calls a "recipe blog," complete with pictures. I'll put a link on my front page.

Recent recipes include:
Quinoa Veggie Stir Fry
Stuffed Bell Pepper with Salsa Verde
Pressure Cooker Pasta Dinner
Chicken Breast Chili

You can also follow Vince on Twitter at @felog and hear about new recipes as they're posted. Like I said....a useful resource for athletes of all sorts.

In the News: Sudden Cardiac Death in NCAA Student Athletes

2011-04-22T07:04:00.000-07:00

An important article appeared in this week's edition of Circulation, one of the American Heart Association (AHA) medical journals. Dr. Kimberly Harmon and her colleagues at the University of Washington wrote an article entitled, "Incidence of Sudden Cardiac Death in National Collegiate Athletic Association Athletes."

We know that sudden cardiac death (SCD) is a sad, but thankfully uncommon, event among student athletes. As I've said before, these events often receive sensational attention in the popular press when they occur. Unfortunately, it has been difficult to get a handle on the number of such events because there is no required reporting of such events. As a result, various investigators have estimated the frequency of SCD to be anywhere from 1 per 23,000 athletes to 1 per 300,000 athletes.

In the newly published article, Dr. Harmon reviewed the records from the National Collegiate Athletic Association (NCAA) that pertained to student athletes who competed from 2004 through 2008. This represented 300,835 athletes aged 17 through 23 years who competed in 40 sports in all three NCAA divisions. In total, there were 1,969,663 athlete participation-years.

The investigators found 273 deaths during that period. The majority of these deaths were not sports-related, with a variety of causes such as accidents, suicides, homicides, and drug overdoses. The cause of death was medical in 80 cases and, among these, the cause was cardiac in 45. Thus, the rate of SCD in NCAA athletes works out to be 1 per 43,770 per year.

The rate of SCD was different for various sports, with the higest rates for the following sports:
Basketball: 1 per 11,394 per year
Swimming: 1 per 21,293 per year
Lacrosse: 1 per 23,357 per year
Football: 1 per 38,497 per year
Cross country: 1 per 41,695 per year.

There are several important implications of the study:

1. We should expect similar rates of SCD for closely younger (high school) and older (adult), non-student athletes. Both of these groups have many more participants than the group of college athletes that was studied.

2. Knowing that an EKG detects upwards of two-thirds of hidden cardiovascular diseases in athletes, it may be prudent to include an EKG as part of a pre-participation physical examination for athletes in the higher-risk sports.

3. Knowing the higher-risk sports may show athletic departments and event planners where to best deploy resources such as automatic external defibrillators (AED's) and on-site health professionals to treat potential victims of SCD.

Can Too Much Exercise Harm the Heart?

2011-04-19T06:04:00.000-07:00

Check out my monthly column at Endurance Corner, where I discuss the potential for (too much) exercise over the long term to cause harm to the heart.

All things considered, this issue hasn't been studied very well. I review some of the pertinent scientific studies that raise important questions in this regard. The findings are certainly preliminary and beg for more research.

In my mind, the health benefits of exercise are well understood, though. I wouldn't stop exercising just yet!

Heart Attack at Tri Camp: A Story for Camp Planners to Remember

2011-03-30T06:07:00.001-07:00

I had the opportunity this past weekend to be Camp Director for a USAT-sanctioned weekend triathlon training camp hosted by our local triathlon club, the Mississippi Heat Triathlon Team. We had a terrific weekend of swim, bike, and run training along with educational sessions in each sport. The campers included more than 60 athletes of all ability levels and our program included a separate track called Triathlon 101 that was designed specifically for beginners. I thought I would share a story from the camp that highlights the importance of safety planning for such events. Our Sunday morning program included breakfast, an hour-long talk about run training, and then a group run. The athletes could choose among 4-, 6-, 8-, or 10-mile groups. We gathered outside in our various groups, each with a coach, had a short briefing about the run, and headed out. Within sight of the neighborhood clubhouse where we started, one of the campers, a 40-year-old man in the Triathlon 101 group, developed severe chest pain. He stopped and the pain gradually subsided over several minutes. Two of his fellow campers, who were both physicians, tended to him and he walked back to the clubhouse where plans were made to drive him to the hospital for evaluation. As it would turn out, he suffered a mild heart attack, underwent cardiac catheterization, was found to have a severe blockage in one of his coronary arteries, and was treated successfully with a coronary stent. He spent 2 nights in the hospital and is now making a good recovery at home. We shouldn't be surprised that serious heart disease can manifest in the setting of a group of "healthy" athletes. Heart disease is common even in this population. Some take-home messages: 1. Planners of athletic events should be prepared to deal with heart-related medical emergencies. There should ideally be on-site medical professionals as well as easy telephone access to EMS, if needed. 2. It's important to recognize that transient symptoms of chest pain or shortness of breath can be related to serious heart problems. 3. Even though there are many health benefits of exercise, athletes assume some finite risk of acute heart-related problems every time they exercise or train.

Some Thoughts on Ideal Heart Health

2011-03-21T12:48:00.000-07:00

My monthly column at Endurance Corner is devoted to the issue of ideal heart health. This topic has been in the news lately and I thought I'd offer some thoughts about the American Heart Association (AHA) "Simple 7." Check it out.

Ironheart Racing Team--An Organization with Heart

2011-03-18T16:33:00.000-07:00

I joined the Ironheart Racing Team today and I wanted to share with you some information about this organization.

Founded by David Watkins as a way to raise awareness about congenital heart disease and healthy heart living, the Team now includes endurance athletes from throughout the United States. They range from beginners to elite and are racing in events ranging from 5K runs through Ironman distance triathlons.

The Team has adopted several charities that focus on heart disease, including the Nick of Time Foundation, the Children's Heart Foundation, Mended Little Hearts, the Adult Congenital Heart Association, and the Walter Sisulu Pediatric Cardiac Foundation.

I encourage you to visit the Ironheart Racing Team website and learn more about this organization. Its heart is in the right place!

Jack LaLanne, Fitness Enthusiast, 1914-2011

2011-03-18T07:31:00.000-07:00

Jack LaLanne was an original--pop fitness enthusiast, nutritionist, and advocate of healthier living. He'l be remembereed as one of the most important influences on Americans' thinking about exercise, health, and nutrition during the 20th century.

Sadly, LaLanne died of respiratory failure and pneumonia on January 23, 2011 at his home in Morro Bay, California, at the age of 96.

Growing up in California, LaLanne took an interest in fitness after a childhood upbringing that was not entirely healthy. He would open one of this country's first fitness centers in Oakland, California, in 1936. There would eventually be many such fitness centers that bore his name.

LaLanne was a staunch advocate of exercise and proper nutrition as means to better health. He wrote several books, developed a variety of exercise machines, and hosted a television program for more than 30 years. In the process, he reached an audience of millions of Americans, coaxing them off the couch. He did a lot of good.

Interestingly, LaLanne underwent heart valve surgery at the age on 95. Details of that operation haven't been widely reported, but I understand that he had aortic valve replacement--probably for aortic stenosis. It's an operation that we perform for patients of almost any age with severe narrowing of the heart valve. Like most patients, he made a good recovery from that operation in spite of his advanced age.

Jack LaLanne was one-of-a-kind. We'll miss him.

In the News: Athletes and NSAIDs

2011-03-01T20:39:00.000-08:00

Last week, my column at Endurance Corner dealt with the topic of athletes and non-steroidal anti-inflammatory drugs (NSAIDs). A new study draws attention to the cardiovascular risks associated with these medications. I'd urge athletes to think twice about NSAIDs when they choose to take these medications.

Commotio Cordis: A Surprising Cause of Sudden Death in Athletes

2011-02-10T12:01:00.000-08:00

Today we're talking about commotio cordis, a surprising (but not rare) cause of sudden death in athletes. The term commotio cordis comes from Latin, and means "agitation of the heart." This is apt.

A typical scenario might unfold like this....

A teenage pitcher on a high school baseball team makes his pitch and the batter hits the ball back directly at the pitcher. The ball strikes the pitcher in the front of the chest, the pitcher falls to the ground....and doesn't get back up. Bystanders react slowly, but tend to the pitcher and find that he is unconscious. It takes a while for the bystanders to realize the gravity of the situation and they eventually begin CPR when they realize that there is no pulse and the pitcher is not breathing. Eventually, somebody thinks to call 911 and EMS providers arrive on the scene some 15 minutes after the incident. They discover that the patient has an arrhythmia called ventricular fibrillation, but despite attempts at defibrillation (shocking the patient), the pitcher cannot be resuscitated and dies. We hear about the episode in a short report in the local newspaper the next day.

What is Commotio Cordis?

We use the term commotio cordis to refer to an incident where an individual is struck by an object in the chest, causing a fatal arrhythmia. This is a different situation that when an individual suffers major trauma (eg, motor vehicle accident) with significant chest trauma and there is evidence of significant injury (eg, contusion) to the heart. In the case of commotio cordis, the trauma is seeminly minor.

It turns out that commotio cordis is probably the second most common cause of sudden cardiac death in young athletes; only hypertrophic cardiomyopathy is a more common cause.

Who Gets Commotio Cordis?

Most instances of commotio cordis occur in young male athletes who are struck in the chest by a projectile such as a baseball. Direct blows to the chest, as in karate or other martial arts, may also be a cause. Other sports where this condition has been reported include softball, ice hockey, football, and lacrosse.

This condition historically received little attention in the broader public media or scientific community. Recently, though, there was the formation of the U.S. Commotio Cordis Registry to keep track of victims. To date, more than 210 cases have been reported.

Among patients in the U.S. Registry, the majority of athletes with commotio cordis were between 10 and 25 years old; 26% were younger than 10 years of age, and only 9% were older than 25 years old.

Almost 50% of commotio cordis events occur during competitive sporting events. The remainder occur, about equally, in daily activities or in recreational sporting activities.

What Actually Happens to the Heart?

In victims of commotio cordis, the impact of a blunt object on the anterior chest wall leads to ventricular fibrillation, a disorganized rhythm of the ventricles that results in ineffective pumping of the heart, and a marked fall in the blood pressure. We've learned from investigations in animal models that the susceptibility to ventricular fibrillation occurs during a very specific, very short period (perhaps just 20 msec) during the cardiac cycle that corresponds to the initial upstroke of the T-wave on the ECG.

Like the photo at the top, it's like hitting the bullseye, but with a baseball or other flying object. The impact on the anterior chest wall must occur at just the precise moment to produce the fatal arrhythmia.

What's the Treatment?

Commotio cordis is usually fatal. With increasing attention paid to this condition, though, the survival rate has increased from about 15% to about 35% over the past decade.

The only effective treatment for invididuals with ventricular fibrillation due to commotio cordis is prompt defibrillation. We know that survivors have received prompt CPR and defibrillation within the first few minutes after collapsing. The survival rate may be less than 5% for victims in whom CPR/defibrillation is delayed more than 3 minutes.

These statistics point to the importance of bystander CPR and the availability of automatic external defibrillators (AEDs) for use by bystanders before trained medical personnel can arrive on the scene.

How Can We be Better Prepared?

Efforts to reduce the frequency (and mortality associated with) commotio cordis are focused in 3 areas: 1) prevention, 2) better awareness, and 3) prompt, effective treatment.

Because of the variety of mechanisms that are responsible for commotio cordis, it's unlikely that athletes could be told to avoid all situations in which commotio cordis might occur. On the other hand, athletes CAN be instructed to turn the chest when a ball is heading toward them, so that it strikes somewhere other than the anterior chest. And, of course, strict attention can be paid to wearing chest protectors for goalies, baseball catchers, etc.

Better awareness about commotio cordis, particularly among athletes and coaching staffs, might help promote quicker recognition of the problem--and then institution of prompt treatment with CPR and defibrillation. Too often now, bystanders don't recognize the life-threatening nature of an athlete's collapse after being struck, and treatment is unnecessarily delayed.

The report from the 36th Conference on Eligibility Recommendations for Competitive Athletes with Cardiovascular Abnormalities made several recommendations about commotio cordis:

1. Age-appropriate safety baseballs are recommended for use in children up to 13 years of age.

2. Although chest wall protectors may prevent traumatic injury in goalies and baseball catchers, insufficient evidence is available to recommend universal use of commercially available chest barriers for all participants in sports, specifically to prevent commotio cordis events.

3. AED's should be available within 5 min after participant collapse at sporting events.

4. Survivors of a commotio cordis with ventricular fibrillation should undergo a thorough cardiac evaluation, including at least 12-lead ECG, ambulatory Holter monitoring, and echocardiogram.

5. Because data are lacking with regard to the susceptibility for recurrent events, eligibility for returning to competitive sports in survivors is at present a decision left to individual clinical judgment.

In the News: Aerobic Exercise Improves Memory

2011-02-03T11:00:00.000-08:00

In a recent blog entry, entitled "Exercise is Good," I wrote about the many health benefits of exercise. As I mentioned, one area of research that has received increasing attention is the area of the cognitive benefits of exercise.

In this week's electronic edition of the Proceedings of the National Academy of Sciences, a group of investigators led by Kirk Erickson, from the University of Pittsburgh, report on an interesting study of 120 older adults (aged 55-80) who were followed for 1 year after beginning an exercise program. Half of the group was randomized to an exercise program that was moderate-intensity aerobic exercise (40 minutes of walking) for 3 days per week. The second half of the group was randomized to an exercise program that was non-aerobic--including only stretching or toning exercises for the same amount of time.

The participants had an MRI of the brain and a test of spatial memory before and after the 1-year study period.

The investigators found that both forms of exercise program were associated with an increase in the size of the patients' hippocampus--an area of the brain that is involved with memory. This increase was approximately 2% for the aerobic exercise group and 1.5% for the non-aerobic exercise group. We know from previous studies that this is an area of the brain that ordinarily shrinks with aging, so the new report offers encouraging news for aging adults.

The second finding from the study was that both forms of exercise program were associated with an improvement in the test of spatial memory. In this case, the aerobic exercise program did not provide any additional benefit over the non-aerobic program.

In interviews with the press, the investigators have characterized their findings as actually "turning back the clock" with the exercise program--not maintaining, but acutally improving patients' memory. Ongoing work is now focused on determining how long these changes in hippocampal size and improved memory will last.

Athletes and Cardiac Pacemakers

2011-01-28T09:10:00.000-08:00

We'll talk today about athletes and cardiac pacemakers. I was reminded by a reader over the weekend that rhythm problems in athletes sometimes necessitate the implantation of a pacemaker. I'll follow-up on today's article with another on athletes and internal cardioverter-defibrillators (ICDs) since I also mentioned these devices a couple weeks ago here at the blog.

The Heart's Electrical System

The heart has a very elaborate electrical system that is designed to initiate and carry electrical impulses throughout the heart, causing the heart muscle to contract (in just the right way) and pump the blood that it holds.

The electrical impulses start in an area in (or near) the top of the right atrium called the sinus node. These impulses are generated automatically and, for most people, have a rate of 60-100 beats per minute. The electrical impulses then spread out over the left and right atria and travel to a way station called the atrioventricular (AV) node. The AV node builds in a slight delay and then the impulses travel to the lower, or pumping, chambers of the heart--the ventricles. As the electrical impulses travel through the ventricles, the pumping chambers contract, ejecting the blood that they hold.

Common Problems That Are Treated With a Pacemaker

There are many disorders of the electrical system of the heart--far too many to discuss here in this article. Indeed, entire textbooks have been written about these problems. For affected athletes who are reading here, it would be wise to discuss your PERSONAL situation with your doctor so that you understand the PARTICULAR electrical problem that you have. Today, we'll focus on just 2 common problems that are sometimes treated with a pacemaker: a slow heart rate (bradycardia) and heart block (the situation where there is undue delay getting the electrical impulses throughout the heart).

Bradycardia is defined as a heartrate less than 60 beats per minute. Sometimes the heartrate can become so slow that affected individuals have problems such as light-headedness--or even black out. We call that symptomatic bracycardia.

Individuals with heart block may have electrical impulses that start at 80 beats per minute at the sinus node, but because of the block, these electrical impulses are delayed (or lost entirely) and the ventricles might beat at only 30 beats per minute--far too slow to manage the necessary pumping function of the heart.

In both of these situations, a pacemaker may be the appropriate treatment.

What Is a Pacemaker?

A pacemaker is an implanted medical device that corrects for a problem with the heart's electrical system. The pacemaker usually consists of 2 parts: 1) a battery (or "generator") that is implanted beneath the skin of the upper chest and 2) a set of wires that are threaded through a vein and fastened to the lining of the heart.

With the most modern pacemakers, the generator is about the size of a stack of 3 half dollars. The battery lasts for several years and will then need to be replaced. The wires (or "leads) are designed to remain in place for a long time--many years, or potentially, forever. The generator and leads are placed during a operative procedure that usually lasts less than an hour and can be done with either local anesthesia and sedation or with general anesthesia.

In the most typical configuration, one lead is placed into the right atrium and another is placed into the right ventricle. These leads are designed to sense the heart's own electrical activity. This information is gathered by the computer that is part of the generator, and then the computer uses those same 2 leads to deliver electrical impulses, as needed, to speed up the heart (in the case of bradycardia) or to provide missing electrical impulses (in the case of heart block).

For patients with pacemakers, the pacemaker can be checked periodically using a hand-held computer device directly over the pacemaker. This device gathers information about the functioning of the pacemaker and about the battery's lifespan and this information can be transmitted either directly or by telephone to the patient's doctor for review. Sometimes adjustments must be made to the settings of the pacemaker to guarantee the most appropriate functioning of the pacemaker.

Issues for Athletes

The first important issue for athletes with pacemakers is the healing time after the pacemaker implantation procedure. Like for any surgical procedure, some time is needed for the body to heal after the operation. For pacemakers, it also takes time for the heart to heal at the location where the leads have been implanted. Until this healing process is complete, the leads can become dislodged inadvertently with vigorous activity. It's common for implanting physicians to recommend no arm activity (on the side of the implant) and no vigorous activity, in general, for a period of several weeks after the pacemaker procedure. After that time, most implanting physicians will allow a gradual return to pre-implantation activities.

In the long term, there continues to be a small risk of lead dislodgement and some physicians recommend that patients avoid athletic activities that place a patient at risk of severe body blows. Many athletes, though, can return to their sports after implantation of a pacemaker, but it's important to have a detailed discussion with their physician about this issue.

The second major issue for athletes relates to the settings for the pacemaker. Each pacemaker system contains a microprocessor that can be programmed to work optimally for an individual patient. One important setting for athletes is the maximal rate setting. As an example, let's consider an athlete with heart block. She exercises vigorously and her sinus rate rises to 180 beats per minute. Ideally, the pacemaker would stimulate her ventricles at the same rate of 180 beats per minute. If the maximal rate setting were only 140, she would have the feeling of "not enough oomph" from her heart to continue the exercise. This is just one example. Athletes will need to have ongoing discussions with their physician about the settings for their pacemaker....and it may take some trial and error to set things up satisfactorily.

For More Information

There are probably many web-based information sources that are useful to athletes who have--or are considering--a pacemaker. After a quick look around, a couple that I like are:

http://www.pacemakerclub.com/ This is a free online "club" designed as a support group for patients with a pacemaker or ICD and their families. There are topical-oriented forums where members can network with people with similar problems and concerns.

http://www.americanheart.org/presenter.jhtml?identifier=4676 This link is to the American Heart Association (AHA) page that deals with pacemakers. At this page, there are additional links for more detailed information on a variety of topics.

http://www.medtronic.com/your-health/bradycardia/index.htm This link is to a page at the Medtronic (a company that manufactures pacemakers) site that deals with bradycardia and pacemakers. There are also additional links to information about related topics.

I'll be back next with an article on Athletes and ICD's.

Exercise is Good!

2011-01-25T08:27:00.000-08:00

In my column today at EnduranceCorner, I write about the health benefits of exercise. Take a moment to visit the EnduranceCorner site for a daily article related to endurance sports. I'm reprinting the article here as well.

It's that time of year when resolutions are on people's minds. As we all know, one of the most common New Year's resolutions is to exercise--often for the stated purpose of losing weight. But exercise is good for so much more. For those who want to keep score, here's a quick tabulation of the documented health benefits of exercise.

Cardiovascular Benefits of Exercise

Lower blood pressure. There is ample evidence that physical activity is associated with lower blood pressure measurements in the general population. Moreover, exercise can be used to reduce the blood pressure (by 5-15 mm Hg) among those with high blood pressure (hypertension). In fact, an exercise program is often a component of the initial treatment of those with borderline or newly diagnosed hypertension.

Better cholesterol profile. Moderate amounts of exercise favorably affect the lipid profile by lowering the LDL ("bad") cholesterol, total cholesterol, and triglycerides and by increasing the HDL ("good") cholesterol. This more favorable lipid profile is associated with reduced risk of coronary artery disease (CAD).

Less chance of stroke. Although there has been conflicting evidence over the years, it is now generally accepted that moderate and high levels of exercise are associated with reduced risk of most types of stroke.

Maintaining an appropriate weight. I'm listing this benefit among the cardiovascular benefits because it is so intertwined with these benefits. Exercise is associated with less obesity and a lower prevalence of metabolic syndrome (a collection of problems such as diabetes, high blood pressure, and abnormal lipid profile).

Other Benefits of Exercise

People who exercise live longer. It doesn't get much better than that! Given the cardiovascular benefits mentioned above, this isn't surprising. It's true for men and women, for smokers or nonsmokers, for the lean or overweight, and for those who are otherwise healthy or not.

In a study of middle-aged men in Sweden who were studied prospectively for a period of 20 years, investigators found that, after controlling for other relevant variables, work-related or leisure-time physical activity was associated with a protective effect on the death rate due to coronary heart disease (CHD), cancer, and, in fact, all causes.

Less chance of cancer. The National Cancer Institute reports that there is very strong evidence that physical activity is associated with reduced risk for colon and breast cancer. Although the data are not conclusive, studies have also shown that there is probably a reduced risk of endometrial (uterine), lung, and prostate cancers as well.

Increased muscle strength. Perhaps this is obvious; it takes muscles to exercise. This benefit is likely more pronounced with resistance than aerobic exercise.

Better immune system. There is accumulating evidence that moderate exercise improves the body's immune system--its ability to fight off colds and infection. The underlying mechanisms are still being investigated. This is a double-edged sword, though. Studies have also shown that "too much" exercise may lead to the opposite effect.

Less diabetes. Adult-onset, or type 2, diabetes mellitus is associated with obesity and a sedentary lifestyle. Those who are physically active are much less likely to develop diabetes. Moreover, a moderate program of exercise is often prescribed as an effective intervention to prevent the development of diabetes among individuals who already show signs of glucose intolerance. Exercise is known to reduce blood sugar levels and to improve the body's handling of insulin.

Better learning and memory. It has been shown that adults who exercise perform better on tests of memory, decision-making, and problem solving. The underlying mechanisms are still being studied, but exercise may increase blood flow to regions of the brain that are particularly involved in these cognitive skills. There is also preliminary evidence, at least in animal models, that physical activity may stimulate the growth of new brain neurons that may be involved in learning and memory.

Better sexual function. There is ample evidence that the incidence of erectile dysfunction is less among men who exercise. Moreover, sexual function and enjoyment are improved among individuals who avoid the problems of the metabolic syndrome, obesity, and diabetes--all of which can be mitigated by exercise.

Less osteoporosis. Especially among older women, continued exercise can help avoid the problems of osteoporosis (loss of bone density) and chronic back pain.

Better sleep. The relationship between exercise and sleep has been studied extensively. In many patient groups, those who exercise have less insomnia and better quality of sleep.

Better mental health. Lastly, there's been increasing awareness and investigation of the mental health benefits of exercise. In a commonly mentioned study, researchers at Duke University found that among 202 individuals suffering from major depression who were treated for 16 weeks, 60% of participants who exercised for 30 minutes three times each week (and received no anti-depression medication) saw improvement in their depression symptoms--the same percentage as for those who used medication(s) alone.

I find almost universally among my athlete friends the opinion that exercise makes us "feel better." That observation is borne out in the various scientific studies that have shown that even small amounts of exercise have been associated with incresed happiness, better energy levels and confidence, and decreased anxiety and tension.

How Much Exercise is Needed?

We've all heard the adage that "if some's good, more's better." That's likely true for exercise, too, at least to some reasonable extent. We'll leave for another day the discussion about the potential adverse effects of too much exercise. But how much exercise is needed to enjoy the good benefits? I'll bet there's no exact amount for any single individual. If the truth were known, there are probably benefits that begin to accrue with even the first few minutes of exercise. After review of the available accumulated evidence, the American Heart Association (AHA) has formulated recommendations for both children and adults. Regarding physical activity and children, the AHA has adopted the following Scientific Position:

"Physical inactivity is a major risk factor for developing coronary artery disease. It also increases the risk of stroke and such other major cardiovascular risk factors as obesity, high blood pressure, low HDL ("good") cholesterol and diabetes. The American Heart Association recommends that children and adolescents participate in at least 60 minutes of moderate to vigorous physical activity each day."

Using similar reasoning, the AHA has adopted the following Scientific Position regarding physical activity in adults:

"Physical inactivity is a major risk factor for developing coronary artery disease. Coronary artery disease is characterized by deposits of fatty substances, cholesterol, calcium, and other substances in the inner lining of arteries that supply blood to the heart muscle. It also contributes to other risk factors, including obesity, high blood pressure, high triglycerides, a low level of HDL ("good") cholesterol and diabetes. Even moderately intense physical activity such as brisk wallking is beneficial when done regularly for a total of 30 minutes or longer on most or all days."

I suspect that most readers here have embraced exercise and made it part of their daily and weekly routine. Most of us have come to recognize a final benefit of exercise--it's fun! This is the time of year when a few encouraging words might help a friend, family member, or co-worker stick with their New Year's resolution to exercise. Look for that opportunity.

Happy New Year!

In the News: NSAIDs and Cardiovascular Risk

2011-01-16T17:28:00.000-08:00

In this months edition of the British Medical Journal, a group of Swiss investigators reported on a large study of patients who received non-steroidal anti-inflammatory drugs (NSAIDs). Their findings confirm previous suspicions that these drugs are associated with an increased risk of cardiovascular complications such as heart attack and stroke.

This scientific study has received a lot of attention in the press this past week. A news account in the online edition of USA Today, "Common pain relievers raise heart risk for healthy people", nicely summarizes the findings and implications.

I will write a longer piece here at the blog that deals with NSAIDs in general and specific recommendations for athletes. Be sure to check back.

Looking for Athletes with an ICD

2011-01-13T20:24:00.000-08:00

Looking for athletes with an ICD....

Since we haven't already had a discussion here at the blog on this topic, internal cardioverter-defibrillators (ICD's) are implantable devices that are designed to deliver a shock to the heart to restore a normal heart rhythm whenever a serious ventricular arrhythmia (an abnormal heartbeat originating in the pumping chambers of the heart) occurs. They are used in patients who have already experienced such a serious arrhythmia and also in patients who are discovered to be at high risk for those same arrhythmias. These are truly life-saving devices.

There are many important issues regarding ICD's and athletes. At this point, the safety of continued participation in sports for athletes with an ICD is simply not known. As a result, most authorities have adopted the conservative recommendation that athletes with an ICD should only participate in low-level activities such as walking or golf.

Dr. Rachel Lambert, a cardiologist at Yale University who specializes in electrophysiology, and her team of investigators is studying the general issue of athletes and ICD's. They maintain an ICD Sports Registry, where they collect data on athletes with an ICD who have continued to participate in rigorous, and even competitive, sports. So far, more than 300 athletes are participating--from high school athletes to marathoners and triathletes, to people playing basketball in a league at the YMCA or tennis at the tennis club. Dr. Lampert's aim is to determine the safety and the risks of sports participation for these athletes so that we might all be able to make more educated recommendations for our athlete patients.

If you have an ICD and are actively participating in sports or vigorous activities, you may qualify to participate in the Yale registry. For more information, please call the ICD Sports Registry coordinating center at 866-207-9813 or email ICDsports.registry@yale.edu. Additional information can be found at the project's website, http://www.icdsports.org.

This is a tremendously worthwhile project and I would encourage you to participate. Help us all learn from your experience.

Excellent Article on Athletes and DVT

2011-01-13T14:28:00.001-08:00

In his monthly column at Endurance Corner, entitled "DVT and Thee," Dr. Bob Albright reviews the problem of deep venous thrombosis (DVT) and pulmonary embolism (PE). This is an excellent article that summarizes the symptoms, treatment, and consequences of these problems, particularly for athletes. Check it out.

Darryl Kile, Professional Baseball Player, 1968-2002

2011-01-09T08:12:00.000-08:00

Darryl Kile, a professional baseball player, died at the age of 33 on June 22, 2002. At the time, he was a star pitcher for the St. Louis Cardinals. The team was in Chicago for a game against the Chicago Cubs and Kile failed to show up at the ballpark for pre-game warmups. Team officials would return to the team hotel to find a "Do Not Disturb" sign on his room door. Sadly, Kile was found dead in his bed, with every indication that he died in his sleep. Kile was survived by his wife and 3 young children.

I can recall the announcer's words at the start of the game broadcast that day: "I thank you for your patience. We regret to inform you because of a tragedy in the Cardinal family that the commissioner has cancelled the game today. Please be respectful. You will find out eventually what has happened, and I ask that you say a prayer for the St. Louis Cardinals' family."

It was a particularly sad week for Cardinals fans. The team's long-time announcer, Jack Buck, died after a long illness earlier in the week.

An autopsy showed that Kile died of a massive heart attack. Two of the three main coronary arteries had 80-90% blockage.

Of course, it's unusual for a seemingly healthy 33-year-old, yet alone a professional athlete, to die from coronary artery disease. Kile had passed the annual team physical which included an EKG and blood tests during spring training. We would come to learn, though, that Kile's father also died shortly after suffering a heart attack in 1993, at the young age of 44.

Kile's death may have been unavoidable. For readers here at the blog who have a family history of coronary artery disease, it's particularly important to pay attention to modifiable risk factors (such as smoking, obesity, diabetes, high blood pressure, etc.) and to any warning signs (such as chest pain/discomfort or shortness of breath) for coronary artery disease.

The Skinny on Your Cholesterol

2010-12-02T03:25:00.000-08:00

I'm reprinting my November column from Endurance Corner.

We’ve reached the off-season for most northern hemishphere triathletes. Our regular readers here at Endurance Corner will know that our daily articles have begun to focus on reviewing the past season and looking ahead to the next. It’s a time for rest, reflection, and planning.

The off-season is also the logical time to pause and reflect on our health and make plans as we look ahead. We should be as deliberate about our health planning as we are about next season’s training plan and goals. This is the opportunity to think about (and schedule) our own preventive health maintenance.

Today, I thought we’d talk about serum (in the bloodstream) cholesterol and lipid levels. Please keep in mind that whole books have been written about this topic, so our discussion here will necessarily only cover the essentials. But every athlete should know the essentials!

Why is your cholesterol level important?

As we get older, the problem of atherosclerotic disease (the development of blockages in the body’s arteries that cause heart attack and stroke, or “hardening of the arteries”) becomes more and more important. In fact, cardiovascular disease is responsible for more than one third of deaths in the United States and claims more lives each year than cancer, accidents, diabetes, and chronic lung disease, combined.

I’ve mentioned previously that there are several risk factors for the development of blockages in the coronary arteries, or coronary artery disease (CAD)—and some of these risk factors can be controlled. By you! Your serum cholesterol and lipid levels fit into this category. To review, the other controllable risk factors are: maintaining a normal blood pressure; not smoking; maintaining a healthy body weight; preventing or controlling diabetes; and thankfully for our readers here, being physically active.

It’s estimated that more than one half of adult Americans have a high serum cholesterol level (>200 mg/dL) and as many as 37 million have a very high serum cholesterol level (>240 mg/dL). It’s a big problem.

We know from large scale population studies conducted over many years that high cholesterol levels are associated with an increased risk of CAD. That risk isn’t linear, though. Unfortunately, the risk of CAD rises exponentially with increasing levels of serum cholesterol:

Recall from one of my earlier columns about sudden death in athletes that the most common cause of sudden death in athletes older than 30 years is CAD. This set of facts should provide sufficient motivation for even the “healthiest” of athletes to take charge of his own personal situation with cholesterol.

The American Heart Association (AHA) recommends that adults have their serum cholesterol (and other lipids) tested every 5 years. Testing should be performed more often if there are abnormal results, if you have known heart or vascular disease, or if you have 1 or more other major risk factors for CAD.

A Little About Cholesterol and Other Lipids

Cholesterol is a naturally-occurring substance found in the bloodstream and throughout the body. It’s a component of various cell structures, including cell membranes, and serves as a building block for many of the body’s hormones. In these roles, cholesterol is essential. You simply can’t do without it!

We get our cholesterol in 2 ways: 1) we eat it, or 2) our liver makes it. Cholesterol in the diet comes from a variety of sources such as meat, eggs, and dairy products. Importantly, though, even if we didn’t eat ANY cholesterol, the body would still make enough cholesterol to satisfy our body’s needs.

Cholesterol circulates in the bloodstream attached to complex molecules called lipoproteins—molecules that contain both fat and protein. These lipoproteins come in various sizes or densities. The 2 most important forms are: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Another form of lipid found in the bloodstream is called triglycerides, a slightly different structure made up of 3 fatty molecules held together tightly.

In common parlance, we call LDL the “bad cholesterol” because high levels are associated with an increased risk of CAD. On the flip side, we call HDL the “good cholesterol” because high levels are actually protective against the development of CAD.

When serum cholesterol and LDL levels are high, the excess amounts can be deposited into the walls of the body’s arteries in the form of plaque, leading to narrowing of the blood vessels and the problems of CAD, stroke, or peripheral arterial disease (PAD).

What’s Normal?

Your cholesterol and lipids can be checked at your doctor’s office or a free-standing laboratory. You might consider searching for opportunities for lipid screening programs that are offered as part of community health fairs, often free of charge. You should also check with your employer or insurance company about potentially free lipid screening as a part of various wellness programs in the workplace.

Your most accurate and meaningful test results will come after a period of overnight fasting. If you choose to be tested without fasting and the results are normal, great. If any of the results are high, you should be re-tested after a period of overnight fasting.

The cholesterol and lipid levels are measured in units of milligrams (mg) per deciliter (dL) of blood serum (the liquid component of the blood). Normal ranges have been established by the National Cholesterol Education Program III:

Serum Cholesterol (mg/dL)

Desirable: less than 200
Borderline high: 200-239
High: more than 240

LDL Cholesterol (mg/dL)

Desirable: 100

Near optimal: 100-129

Borderline high: 130-159
High: 160-189

Very high: more than 190

HDL Cholesterol (mg/dL)

Low: 40

High: more than 60

Triglycerides (mg/dL)

Normal: 150

Borderline high: 150-199
High: 200-499

Very high: more than 500

Who Should Get Treated? And How?

If you have high cholesterol or LDL levels, should you be treated? Probably so. The extent of treatment, though, depends upon your overall risk of heart disease. Decisions about drug therapy should only be made with your doctor, who can work together with you to find the best treatment option(s).

All individuals, regardless of their cholesterol or LDL levels, probably benefit from the following therapeutic lifestyle changes (TLC’s):

1. An appropriate diet
a. Saturated fat makes up less than 7% of calories

b. Cholesterol intake less than 200 mg per day

c. Consider increasing viscous (soluble) fiber intake (10-25 g per day)

2. Weight management

3. Increased physical activity

For individuals who already have problems with CAD, stroke, or PAD, the TLC’s should be recommended and drug therapy with a statin medication should be started. The goal of drug therapy is to reduce the LDL level to 70 to 100 mg/dL.

For individuals with 2 or more risk factors for CAD (from among smoking, high blood pressure, low HDL [less than 40 mg/dL], family history of early heart disease, and increased age [men older than 45 years, women older than 55 years]), drug therapy should be considered if TLC’s alone are not successful in reducing the LDL level to less than 130 mg/dL.

For individuals with 0 or 1 of these risk factors, drug therapy should be considered if TLC’s alone are not successful in reducing the LDL level to less than 160 mg/dL.

Many individuals with an elevated serum triglyceride level should also be treated, but the choice of the most appropriate treatment is not as clear-cut and I’d recommend having a discussion with your doctor in this situation.

Some Thoughts About Endurance Athletes and Lipid Levels

Avid endurance athletes are in a fortunate position. Even as little as 30 minutes of exercise daily can result in substantial increases in the serum HDL level which can protect against heart disease. It’s important to remember that in some young, healthy athletes, the total cholesterol level may be relatively high but due primarily to an elevated HDL level that is actually helpful.

Endurance athletes are also likely to be “tuned in” to their diet and can favorably adjust their fat intake to make a difference in their serum cholesterol and LDL levels. Foods that tend to increase the cholesterol level include trans fats and saturated fats (meats, whole milk dairy products, tropical oils, cocoa butter). Foods that tend to decrease the cholesterol level include polyunsaturated fats (nuts, seeds, corn, soybeans, and their oils) and monounsaturated fats (fruits and oils).

Now you’re educated. Take charge and add this to your off-season preventive maintenance checklist.

Skip a Beat Lately?

2010-10-27T11:42:00.000-07:00

My monthly column at EnduranceCorner this month was about endurance athletes and atrial fibrillation (AF). This is a topic that we've visited here at the blog previously, but I've added a recent race story of a triathlete who has been bothered by AF for a couple years. Interesting reading.

Who hasn’t said, at some point or another, that my heart “skipped a beat”? As it turns out, the heart rarely “skips” a beat in the literal sense, but there are a variety of abnormal heartbeats or heart rhythms (called arrhythmias) that cause us to feel like our heart skipped a beat.

When the heart “skips” a beat, the heart rate becomes irregular. More often than not, this involves an extra heartbeat (such as a premature atrial contraction, or PAC) or an arrhythmia. Today, we’ll talk about one of these arrhythmias--atrial fibrillation (AF). This is the most common arrhythmia that affects athletes.

The Normal Heartbeat

First, let’s take a moment to consider the normal situation with the heartbeat. The heart is truly an amazing pump. Its pumping chambers (the ventricles) contract upwards of 5,000 times per hour (even at rest)—and this continues hour after hour, day after day, for a good many years, we hope!

There is an equally amazing electrical system responsible for making that pump work efficiently. The electrical activity of the heart begins with a self-initiating impulse in the sinus node, located in the right atrium (the upper chamber on the right side of the heart). That impulse travels across to the left atrium, then downward to the left and right ventricles. When this electrical system is working properly, the muscle of the atria and ventricles contracts at just the right time to make the pump work as efficiently as possible.

In the ordinary situation that I’ve just described, we say that there is a sinus rhythm, a heartbeat that starts in the sinus node. If the heart rate is 60 to 100 beats per minute, we call the rhythm normal sinus rhythm. Any rhythm other than normal sinus is called an arrhythmia.

When there is sinus rhythm and the heart rate is slower than 60 beats per minute, we call the arrhythmia sinus bradycardia. When there is sinus rhythm and the heart rate is greater than 100 beats per minute, we call the arrhythmia sinus tachycardia. In the interest of full disclosure, it turns out that these are actually the most common arrhythmias in athletes. We know that for many (if not most) well-trained endurance athletes that the resting heart rate is less than 60 beats per minute. In that case, sinus bradycardia is expected and totally healthy. It’s also true that, with exercise, the athlete’s heart rate will often exceed 100 beats per minute. So, sinus tachycardia is also totally expected and healthy.

Atrial Fibrillation

AF is the most common sustained arrhythmia in the general population. With AF, the electrical activity in the upper chambers of the heart becomes totally disorganized. Instead of the usual clock-work contraction pattern, the atria almost quiver instead. The electrical signals reach the ventricles in a disorderly pattern and often at a faster-than-usual rate. The heartbeat becomes irregular (a hallmark sign of this problem) and this can be appreciated when you feel your pulse (at your wrist or neck). The AF may be constant (termed persistent or chronic) or intermittent (termed paroxysmal).

From the physiologic standpoint, the major immediate consequence of AF is a reduction in cardiac output, the amount of blood that the heart pumps (per unit of time). There is undoubtedly variability in the degree to which individuals are affected, but the reduction in cardiac output due to AF is often estimated to be 15% or so.

If we think about the general population, the chances of having AF increase with age, from nearly 0% at age 20 to more than 8% at age 80. This is a reflection that AF often accompanies other forms of heart disease such as mitral valve prolapsed or rheumatic heart disease, or a variety of medical problems such as hyperthyroidism (caused by an overactive thyroid gland). When AF occurs without other heart or medical diseases, we call it “lone atrial fibrillation.”

Why is AF important? In the United States, more than 2 million individuals have AF—and many of these are athletes. The arrhythmia is associated with a variety of poor long-term outcomes, including stroke, heart failure, and even death. The mortality rate for individuals with AF is nearly twice that for individuals without AF.

The Athlete and Atrial Fibrillation

It turns out that AF is 2-3 times more common in athletes than in non-athletes. The reason is not entirely clear, but there are several possible explanations. First, it’s likely that the cardiovascular stresses placed on the athlete’s heart over the long term result in structural changes (scarring) in the muscle of the atria which predispose the athlete to irregular electrical activity in the atria. Second, during exercise there is increased firing of various autonomic nerves that supply the heart—and these may disrupt the heart’s normal electrical activity. Lastly, low-level chronic inflammation produced by training has been proposed as a potential mechanism.

In athletes, paroxysmal AF is much more common than persistent AF, but either form can impair the athlete’s performance. During episodes of AF, the athlete might report a variety of symptoms, including fatigue, unusual or unexpected shortness of breath, dizziness, or palpitations (the physical sensation of the irregular heartbeat).

From a performance standpoint, the athlete is affected because of the reduced cardiac output that accompanies this arrhythmia. You can imagine the detrimental effect, during exercise, of a sudden reduction of 15% in the cardiac output. It would seriously limit any top-end effort and would add physiologic stress to any moderate effort.

A Triathlete’s Story

Let me share with you the story of a ~40 year old triathlete who recently competed in the Ironman Louisville race. He had been bothered by AF but was generally able to train well. At his blog, Run on Energy, he describes how the AF affected his race. The account is very typical for how paroxysmal AF can disrupt either training or racing.

This picture shows the heart rate data during the bike leg of his race. It’s remarkable for the number of spikes to heart rates of nearly 200. The accompanying firsthand account is interesting because it describes this athlete’s reaction to the problem and the resulting decrease in performance for the bike leg of the race. Again, this is very typical for athletes with AF.

Treatment

Caffeine can be related to the occurrence of PAC’s or AF and we often ask affected patients to discontinue caffeine as a first step at treatment.

Medical treatment. A variety of medications are available for patients with AF and are focused on 2 approaches: 1) rate control, to limit the heart rate during periods of AF or 2) rhythm control, to try to prevent AF or convert AF back to sinus rhythm. The typical rate control medications include beta-blockers (eg, propranolol, atenolol, metoprolol) and calcium channel blockers (eg, diltiazem, Verapamil). The typical rhythm control medications include Amiodarone, among others. Unfortunately, though, the success rates for these medications are only about 50%, and the medications may be even less effective in athletes. Moreover, each of these medications comes with potentially adverse side effects.

Another consideration for patients with AF is anticoagulation, or blood thinning, to prevent small blood clots from forming in the atria. These blood clots can break loose, travel through the bloodstream to the brain, and produce stroke. For athletes with no other form of heart disease besides AF, an aspirin each day is probably prudent. For those with other forms of heart disease, a stronger anticoagulant such as Coumadin may be recommended to reduce the long-term risk of stroke. Unfortunately for the athlete, blood thinning with Coumadin also carries a risk of serious bleeding in the event of bodily injury (such as a bike crash), so decisions about anticoagulation deserve much consideration.

Ablation treatment. Another option for individuals affected by AF is ablation, which can be performed either as a catheter-based procedure or as a conventional surgical procedure. With the catheter-based procedure, small catheters can be threaded up to the heart, starting from the arteries or veins of the arms or legs. Electrical energy is then used to ablate (destroy) muscular tissue in the heart walls that is responsible for starting or propagating the AF. In the surgical version, small incisions are made on each side of the chest and specialized instruments are introduced into the chest cavity to perform the ablation on the outside of the heart muscle. For patients with paroxysmal AF, the success rates for these procedures is quite good. For patients with persistent AF, the success rates are not quite as good.

What to Do?

Athletes with an irregular heartbeat—either intermittently or permanently—should seek medical attention. It’s important to sort out the cause of an irregular heartbeat, particularly if the problem disrupts training or racing. Luckily, most athletes with AF can continue to participate fully in their sports.

Who's Your Doctor?

2010-10-05T11:14:00.000-07:00

Each week I get emails from readers who are looking to find a doctor in their area. By and large, I'm not able to offer very specific help since I don't know many doctors outside my area here iin Jackson, Mississippi.

I know that athletes are looking for doctors who are "tuned in" to the issues that athletes face....not only the injury-related issues, but also issues of ongoing health and nutrition.

I'm hoping that we might share information about doctors we'd recommend to our friends. If you have a doctor (or just know of a doctor in your area) who would be great for an athlete, please let me know (either a comment here at the blog or by email). And let me know what your like about your doctor. I'll post a list of these doctors as a resource to the readers here at the blog. I won't be able to "vouch" for these doctors, but I know that a recommendation from a fellow athlete may be meaningful to others out there who are looking for a doctor.

Thanks!

More on Laboratory Screening in Athletes

2010-09-29T11:38:00.000-07:00

In my July column at EnduranceCorner, I wrote an article entitled, "What is Your Blood Telling You?" I get many questions from athletes asking how to interpret the various common blood tests and I offered this article to lay out some useful information about these tests.

My Recommendations

In that article, I also offered a recommendation about which tests might be useful, on a regular basis, for endurance athletes who might be readers. I suggested an annual physical examination (with particular attention to the cardiovascular system), an annual complete blood count (CBC) and basic metabolic profile (BMP). I also suggested that a lipid profile (total cholesterol, low density lipoprotein [LDL], high density lipoprotein [HDL], and serum triglycerides) be checked every 5 years in accordance with recommendations from the American Heart Association (AHA). Finally, I recommended an EKG and echocardiogram, once, at some point early in an athlete's career to rule out most of the hereditary conditions that predispose athletes to sudden death.

I've received a variety of comments about that article, not only here at the blog but also by email, phone, etc. There were those who felt that my recommendations went too far....and there were those who felt that my recommendations didn't go far enough! Given the balance of replies, I'm probably in the right spot on the issue. Importantly, I still believe that my recommendations are prudent for most endurance athletes and I would urge you to adopt these simple recommendations.

A Noteworthy Study

In fairness to those who wrote to let me know of the futility of routine screening blood tests, particularly in athletes, I thought I would share with you the findings of a recent study on this topic. The report comes from a K. E. Fallon, the Head of Sports Medicine at the Australian Institute of Sport and is entitled, "The clinical utility of screening of biochemical parameters in elite athletes: analysis of 100 cases."

Fallon notes that there are several reasons that have motivated routine blood tests in athletes, including:

1. the goal of establishing a "normal" range for athletes;

2. the goal of establishing, for an individual athlete, a baseline set of values that could be useful should medical problems develop; and

3. the goal of being able to diagnose (or better yet, predict) a state of overtraining.

Although each of these goals may be important, it is important to remember that routine laboratory screening is costly--and in most cases, that cost is not covered by medical plans in the United States.

The study included 100 elite athletes (56 men, 44 women) from 11 different sports (rowing, football, basketball, netball, boxing, athletics, swimming, volleyball, athletics for AWD, archery, canoeing). The list of screening blood tests included: serum iron, ferritin, transferin, percent transferrin saturation, sodium, potassium, chloride, calcium, magnesium, phosphate, urate, urea and creatinine, total protein, albumin, creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransaminase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma-glutamyl transpeptidase (GGT), total bilirubin, cholesterol and triglycerides (non-fasting), and random glucose.

If abnormal results were obtained once, the athlete was interviewed for clinical symptoms, and repeat blood testing was performed.

It turns out that 18 athletes had no abnormalities on the screening tests. A total of 194 abnormal results were identified in the remaining 82 athletes. Of those, 43 tests did not return to normal on the repeat test. The most common abnormalities were increases in AST (27%), phosphate (13%), CK (13%), urea (12%), and bilirubin (12%). Three cases of lipid disorders and 1 case of hemochromatosis were identified. An additional athlete eventually received the diagnosis of Epstein-Barr virus infection, suspected because of an abnormal liver function test.

Fallon concluded that most abnormal blood test results from routine screening had no clinical significance and that routine screening should be abandoned.

Final Thoughts

Like I said above, I still like my recommendations of a yearly physical examination, CBC, and BMP along with a lipid profile check every 5 years. Beyond that, I suggest that you work with your physician to determine which, if any, additional screening tests may be useful for your particular situation. And I think we can all agree that targeted laboratory tests that are selected to confirm or exclude diagnoses that are suspected clinically, are still useful.

The Triathlete's Heart

2010-09-18T05:25:00.000-07:00

In my September column at EnduranceCorner, I shared the findings from a recent study of triathletes' hearts. A team of radiologists in Germany used cardiac MRI to make measurements of the sizes of each of the heart's chambers as well as the thickness of the heart muscle in a group of elite triathletes. Their findings show the adaptive changes in the heart that occur with chronic endurance training.

Two Stories, Two Endings

2010-09-16T16:32:00.000-07:00

In my August column at EnduranceCorner, I told the stories of Jim Fixx and a young triathlete that I've come to know over the past few months. Each was affected by coronary artery disease (CAD). Jim Fixx, the legendary runner and author, died suddenly from his heart disease. My triathlete friend recognized the important warning signs, sought treatment, and is now making a return to his athletic pursuits.

CAD is the most common cause of sudden death in athletes over the age of 30. Best to become educated about the topic and be proactive with your heart health.

What is Your Blood Telling You?

2010-07-23T07:06:00.000-07:00

In my column this month at Endurance Corner, I write about laboratory (blood) tests that may be useful for athletes. I'm frequently asked which tests are useful and also how to interpret the results of the various tests. I provide some recommendations about how to work with your physician to decide when laboratory testing may be useful for you....in your particular circumstance.

Don't Play If....Part 2: Heart Valve Problems

2010-05-21T08:07:00.000-07:00

This is the 2nd part in a series of blog posts that I'm devoting to the issue of "continued participation" for athletes who discover they have a heart condition of some sort. In the 1st part, I outlined a scheme to classify the various sports based upon their degrees of static or dynamic intensity. Today, I'm going to cover some of the common heart valve problems that athletes might encounter....and offer some thoughts about how these conditions impact "continued participation." Just as in part 1, I'm drawing on the opinions from a consensus report, the 36th Bethesda Conference, that was formulated by a variety of medical experts who met in 2004 to review all of the accululated evidence in this area.

Let's recall that there are 4 valves in the heart--2 each on the left and right sides of the heart. These valves are there to keep blood moving in 1 direction only. No backing up of blood, ordinarily. On the right side of the heart, the tricuspid valve is between the upper chamber (atrium) and lower chamber (ventricle) and the pulmonary valve is at the exit from the right ventricle. On the left side of the heart, the mitral valve is between the atrium and ventricle and the aortic valve is at the exit from the left ventricle (into the aorta, the blood vessel that carries blood to the rest of the body).

A variety of valve problems is possible, but they come in just 2 sorts: narrowing (that we call stenosis) or leaking (that we call regurgitation). Either of those sorts of problem makes the heart (as a pump) less efficient as it does its job. And, as you can imagine, these problems come in degrees that we could call mild, moderate, or severe.

By far, athletes are affected by problems of the valves on the left side of the heart--the mitral and aortic valves. Those are the problems that we'll discuss here today.

Mitral Stenosis

Mitral stenosis is usually due to rheumatic disease and produces problems with breathing or arrhythmias. The severity of mitral stenosis is determined by echocardiogram, where the orifice area of the valve can be measured: mild (>1.5 cm2), moderate (1.0 - 1.5 cm2), or severe (less than 1.0 cm2).

1. Mild mitral stenosis. Athletes can participate in all sports.

2. Moderate mitral stenosis. Athletes can participate in low-moderate dynamic or low-moderate static sports.

3. Severe mitral stenosis. Athletes should not participate in any competitive sports.

4. For athletes with mitral stenosis AND arrhythmias, different recommendations may apply.

5. Athletes with mitral stenosis who are taking anticoagulants (blood thinners) because of arrhythmias should avoid sports where bodily contact injuries are possible.

Mitral Regurgitation

Mitral regurgitation can be due to many different causes. Over time, the left ventricle (pumping chamber) may enlarge to compensate for this problem. The severity of mitral regurgitation is determined by echocardiogram subjectively as mild, moderate, or severe.

1. Athletes with mild to moderate mitral regurgitation and no other heart problems may participate in all sports.

2. Athletes with mild to moderate mitral regurgitation and mild left ventricular enlargement may participate in low-moderate static or low-moderate-high dynamic sports.

3. Athletes with severe mitral regurgitation and left ventricular enlargement should not participate in any sports.

4. Athletes with mitral regurgitation who are taking anticoagulants (blood thinners) because of arrhythmias should avoid sports with a high risk of bodily contact injury.

Mitral Valve Prolapse

The frequency of mitral valve prolapse in the general population is 2% to 3%. Athletes with MVP can participate in all sports if they don't also have:

1. History of syncope (blacking out)

2. History of arrhythmias

3. Mitral regurgitation

4. Weakened pumping of the left ventricle

5. History of stroke

6. Family history of MVP-related sudden death.

Athletes who have any of these features should participate only in low intensity sports or have a detailed discussion with their physician about continued participation.

Aortic Stenosis

Aortic stenosis, or narrowing of the aortic valve, produces symptoms of shortness of breath, syncope (blacking out), or chest pain, but these symptoms occur late in the course of this disease. Aortic stenosis may be suspected based on the presence of a characteristic heart murmur on physical examination. Echocardiography is used to classify aortic stenosis according to the valve orifice area: mild (>1.5 cm2), moderate (1.0 - 1.5 cm2), or severe (less than 1.0 cm2).

1. Athletes with mild aortic stenosis may participate in all sports.

2. Athletes with moderate aortic stenosis who have NO symptoms may participate in low intensity sports. Special exercise testing may be used to identify some such athletes who may safely participate in moderate intensity sports.

3. Athletes with severe aortic stenosis and those with moderate aortic stenosis who have symptoms should not participate in any competitive sports.

Aortic Regurgitation

Aortic regurgitation may be due to a variety of causes. Over time, the left ventricle enlarges and pumps less effectively. Echocardiography is used to classify the degree of regurgitation subjectively as mild, moderate, or severe.

1. Athletes with mild to moderate aortic regurgitation, no symptoms, and no other heart problems may participate in all sports.

2. Athletes with severe aortic regurgitation and left ventricular enlargement OR those with moderate aortic regurgitation who have symptoms should not participate in any sports.

3. Athletes with aortic regurgitation and enlargement of the ascending aorta (the blood vessel that carries bloodflow away from the heart) should participate in only low intensity sports.

Don't Play if.... (Part 1)

2010-05-01T16:22:00.000-07:00

I appreciate the many iquiries I've received from readers about their particular situations with heart disease. I'm always happy to lend an ear. One of the more common questions has been something like:

"I recently learned I had 'x' and my doctor says I should stop 'y'. What do you think?"

For the purposes of our discussion here, 'x' could be any heart or vascular condition and 'y' could be any particular sport that interested the reader

I can always provide some information that helps people understand their situation better, but I encourage folks to work through the issue of continued participation with their own primary care physician or cardiologist. It's just so important to have a good relationship with these physicians in order to make the best (and safest) decisions. And it's virtually impossible for me, at the other end of an email, to appreciate all of the many factors that will be obvious to an athlete's own caregivers.

That said, I thought I'd devote the next couple blog posts to a discussion of the general issue of continued participation for athletes who are found to have various heart conditions. And I'm going to rely on a report issued by the American College of Cardiology Foundation after a consensus conference of experts met in November, 2004 to review all of the available evidence on this issue. This is the most thoughtful, authoritative report on this topic. The report is entitled, "36th Bethesda Conference: Eligibility Recommendations for Competitive Athletes with Cardiovascular Abnormalities." The report is available online for those with interest, but the report is targeted toward physician caregivers and doesn't seem to be particularly accessible to non-medical folks.

There are a handful of true experts on this topic around the United States, but most physicians who treat athletes will be relying on this report when they make recommendations to their athlete patients.

What are the cardiovascular demands of your sport?

Today, we'll talk about the cardiovascular demands of various sports. This is really the starting point for discussions with individual athlete patients....because recommendations about continued participation depend not only on the particular heart condition involved, but also on the particular sport involved. Any recommendation will depend upon the expected risk that accompanies continued participation; and that risk stems from the cardiovascular demands of the particular sport.

We should classify sports in terms of their "dynamic" and "static" components. By dynamic, we refer to exercise that involves changes in muscle length and joint movements that are accompanied by relatively small intramuscular force. By static, we refer to exercise that involves a large intramuscular force that results in no (or relatively small) change in muscle length. As examples, long distance running has a large dynamic component and a small static component. Weight lifting has a large static component and a small dynamic component.

Let's consider, for a moment, the opposite ends of the spectrum....a purely dynamic sport and a purely static sport. The cardiovascular effects of the sports are somewhat different and are summarized in this table:

Over time, participation in either dynamic or static sports results in increased cardiac mass. There is enlargement of the heart's chambers as well as thickening of the heart's walls.

A Useful Classification

But of course, no single sport is solely dynamic or solely static in nature. Instead, there is a combination of dynamic and static components. The following table is a useful scheme for classifying sports based on their dynamic and static components:

It's important to recognize, though, that there is probably a great deal of variability in the intensity with which athletes approach their sports, so this classification is only a starting point.

In the next post, I'll talk about recommendations for athletes with specific heart conditions. And we'll be referring back to this classification of sports.

Heart of the Matter

2010-04-29T13:17:00.000-07:00

Check out my column, "Heart of the Matter" at the Endurance Corner website.

A Useful Resource

2010-04-24T11:24:00.001-07:00

I'd like to draw your attention to a useful website. The folks at WebMD and Medscape have a website, http://theheart.org, that is devoted to providing information about diseases of the heart and circulation, and particularly their treatment and prevention. The website's primary audience is healthcare professionals, but there is much worthwhile information at the site for patients and family members, as well. I'll put a permanent link to the site at the right.

There are sections of the website that are devoted to topics such as arrhythmia news, metabolic syndrome news, acute coronary syndrome, etc.

For healthcare professionals, and particularly those who work in the broad field of cardiovascular medicine, this site provides up-to-the-minute information about breaking news in the field.

For the endurance athletes out there, one way to make use of this site would be to find information that interests you, or concerns your particular medical condition, and then discuss this with your own physician.

Subscribe by Email

2010-04-23T13:20:00.001-07:00

A couple folks asked about subscribing by email. So I've added a subscription tool (by FeedBurner) at the right that will allow you to subscribe by email.

Sign up and get my blog posts by email. Nothing easier!

Join Me at Endurance Corner

2010-04-15T12:53:00.000-07:00

Starting this month I'll be writing a monthly column for Endurance Corner.

The triathlon folks who visit here at the blog may already be familiar with Endurance Corner, the company owned by Gordo Byrn, a long-time Ironman triathlete and former Ultraman World Champion. The Endurance Corner crew is a terrific group of people. Starting earlier this month, a variety of columnists are featured each weekday at the Endurance Corner website, http://www.endurancecorner.com/. The fare includes everything from training info, to triathlete bios, to recipes, and musings on life in general.

Stop by and check it out. I know there'll be something to learn there....for triathletes, but also for athletes in general.

In the News: Some Good News for Endurance Athletes

2010-04-13T14:12:00.000-07:00

In recent weeks, I've talked about some of the potentially adverse effects of long-term participation in endurance sports. I've drawn your attention to a couple recent studies that have shown that: 1) endurance athletes are more apt to develop atrial arrhythmias, sometimes long after their participation in sports has ended; and 2) marathon runners may have more plaque build-up in their coronary arteries over time than their non-runner counterparts. Each of these issues deserves further study.

On the brighter side, today's edition of the Journal of the American College of Cardiology features a report by a group of investigators in Rome, Italy, headed by Antonio Pelliccia, MD, entitled "Long-Term Clinical Consequences of Intense, Uninterrupted Endurane Training in Olympic Athletes." I'd like to draw your attention to both this article and an accompanying editorial by Drs. Paul Bhella and Benjamin Levine because they offer some good news about long-term heart health in endurance athletes.

The current study was motivated by several observations. As Drs. Bhella and Levine note, the primary cardiovascular adaptation in elite endurance athletes is a very large stroke volume (the amount of blood the heart ejects with each beat), "achieved by a compliant heart that relaxes quickly." But is there any harm that comes with these adaptations? We do know that there is a consequence known as "cardiac fatigue," a temporary reduction in heart pumping function following endurance events such as Ironman distance triathlon. We also know that there is release of cardiac enzymes (suggesting heart damage) into the bloodstream after marathon running events. What's not known is whether there is damage to the heart over the long term.

The current study involves 114 Italian athletes from a variety of endurance disciplines (55 rowers, 19 cyclists, 8 middle-distance runners, 9 long-distance runners, 15 cross country skiers, 6 swimmers, and 2 triathletes) who participated in at least 2 consecutive Olympic games. These athletes had participated in their sports for anywhere from 1 to 15 years before selection to their first Olympic team and continued to participate in their sports for 4 to 17 years after selection to their first Olympic team. This group of athletes participated in a total of 344 Olympic games and 42 (37%) were medalists at least once.

The athletes were tested before their first Olympic games (baseline evaluation) and again (final evaluation) at their final Olympic games (or World Championships). The average time between the 2 evaluations was 8.6 +/- 3.7 years. Their cardiac evaluation at these 2 timepoints included:

1. physical examination
2. measurement of the blood pressure
3. exercise EKG
4. echocardiogram (ultrasound test of the heart).

Over the period of observation, the authors reported that there were NO cardiac events or new diagnoses of cardiomyopathy (weakening of the heart muscle). In addition, the echocardiograms showed that there were no abnormalities in the pumping function of the heart and that the dimensions of the cardiac chambers were unchanged except for a small increase in the size of the left atrium.

This news should be encouraging to the many endurance athletes out there. It's really the first study to document preserved heart function after years of intense training and competition among endurance athletes. I suppose it's important to recognize that the study population here is VERY select. Indeed, there are relatively few athletes who fit into the category of repeat Olympians. But the results are probably meaningful to the many millions of us who engage in some form of endurance sport. And this time, it's good news.

In the News: Coronary Plaque Build-Up in Marathoners

2010-04-06T12:55:00.000-07:00

Dr. John Mandrola, a cardiologist (specializing in electrophysiology) in Louisville, KY, who blogs at http://www.drjohnm.blogspot.com, brought an interesting report to my attention the other day.

Included among the abstracts presented at the recent annual meeting of the American College of Cardiology was a report from Dr. Jonathan Schwartz (from the University of Colorado) and his father, Dr. Robert Schwartz (from the Minneapolis Heart Institute). It turns out that father and son investigators are both runners.

These investigators examined a group of 25 runners who had completed the Twin Cities marathon for 25 consecutive years and compared these runners to a control group of non-athletes that were similar in terms of age, restinig blood pressure, renal function, smoking history, height, total and LDL cholesterol, and triglycerides. The runners did have a lower heart rate, weight, and body-mass index and higher HDL cholesterol levels.

All of the subjects underwent coronary CT angiography (CTA). This is a relatively simple x-ray test designed to find build-up of calcium in the coronary arteries (the arteries that supply the heart itself). And recall that when these arteries become blocked with calcium-laden plaque, problems such as angina or heart attack (myocardial infarction) may occur.

The investigators found that there was a significantly higher calcium plaque volume in the runners than in the control group. Sixty percent higher, in fact.

Why could this be? Again, the healthy benefits of exercise have been well-established. But the authors here suggest that these healthy benefits might be "counterbalanced by metabolic and mechanical considerations" and that the calcium plaque build-up may be "a response to high exercise levels across a lifetime."

There have been precious few studies of the long-term effects of (potentially excessive) exercise on the cardiovascular system, so we really don't know the cause of these findings. But it could well be the case that, beyond some point, the chronic effects of participation in endurance sports may actually be harmful.

Reports like this make you think.

In the News: Get an EKG?

2010-03-22T07:07:00.000-07:00

We've talked previously here at the blog about the general issue of pre-participation screening for cardiovascular disease for athletes at all levels. In the United States, this has been well-organized for high school and collegiate athletes, but lacking for adult athletes beyond their school days. The typical approach to pre-participation screening invovles taking a medical history and performing a physical examination with particular attention to the heart and cardiovascular system. There has been an ongoing debate about whether the addition of an electrocardiogram (EKG or ECG) and/or an echocardiogram provides additional useful information in a cost-effective manner.

I'd like to draw your attention to 2 articles and 1 editorial that appeared in the May 2 issue of the prominent medical journal, Annals of Internal Medicine.

1. Wheeler MT et al. Cost-effectiveness of preparticipation screening for prevention of sudden cardiac death in young athletes. Ann Intern Med 2010; 152:276-286.

2. Baggish AL et al. Cardiovascular screening in college athletes with and without electrocardiography. Ann Intern Med 2010; 152:269-275.

3. Maron BJ. National electrocardiography screening for competitive athletes: Feasible in the United States? (Editorial) Ann Intern Med 2010; 152:324-326.

In the first study, Wheeler et al. report that the addition of an ECG to the pre-participation physical examination saves 2.06 lives per 1000 athletes screened, at a cost of $88 per athlete. This results in a cost-effectiveness ratio of $42,900 per life-year saved. For reference, most interventions with a cost-effectiveness ration of <$100,000 per life-year saved are deemed worthwhile from the medical and societal standpoints.

In the second study, Baggish et al. report that, among 510 collegiate athletes who received an ECG and echocardiogram in addition to a physical examination, 11 athletes (2.2%) were identified who had a cardiac problem that was significant. Five athletes were identified on the basis of physical examination alone and 5 more were identified by the ECG. Importantly, though, screening that included an ECG resulted in a false-positive rate of 16.9%--a fair number of athletes who had an "abnormal" ECG but in whom no heart disease was actually present.

In the editorial, Dr. Barry Maron, perhaps the country's foremost expert in this area considers the issue of mandating an ECG for school-related pre-participation screening programs. He reminds us of how rare it is for young athletes to die from sudden death: 1 per 220,000 participants. He also points out that the cost of ECG screening for all school-aged students would probably cost upwards of $2 billion. He concludes that the merits of ECG screening are not yet fully established and that there are significant logistical challenges to mandating widespread ECG screening for school-aged athletes.

So, what should my adult athlete readers take from all of this?

Here's what I recommend to my friends.... I think that every endurance athlete should have, at least on 1 occasion, an ECG and an echocardiogram to rule out the major congenital heart conditions that predispose athletes to sudden death. This should be combined with an annual physical examination and medical history-taking that focuses on the heart and cardiovascular system. Athletes should discuss this issue with their physician, who is in the best position to help make decisions about ongoing screening for the development of heart disease as the athlete ages.

Triathlete Death During 2009 Ironman Canada

2010-02-26T08:45:00.000-08:00

At the Ironman Canada triathlon last August, Canadian triathlete Walter Eugene Wiwchar became distressed during the swim portion of the race and died.

This article in the online edition of the Penticton (British Columbia) Western News chronicles the day's events. The article does not completely describe the sequence of events, but apparently Wiwchar was rescued from the water near the completion of the swim portion when he indicated he was in distress. By the time he was rescued, he was unconscious.

The article reports that an autopsy showed that the cause of death was drowning, but that Wiwchar had the condition called aortic dissection--a tearing apart of the layers of the portion of the aorta that carries blood away from the heart and to the rest of the body. The article speculates that the physical distress caused by the aortic dissection probably led, in turn, to the drowning.

We've mentioned aortic dissection previously here at the blog, in relation to individuals (like Flo Hyman) who have the Marfan Syndrome. These individuals are particularly predisposed to the problem of aortic dissection. It turns out, though, that most individuals who suffer aortic dissection do not have Marfan Syndrome. It turns out that nearly all individuals with aortic dissection have high blood pressure (that is poorly controlled).

The consequences of aortic dissection are always serious and often fatal. Even with immediate medical attention (and possible surgery to correct the problem), many affected patients die. The most obvious key to prevention of this problem is vigorous treatment of high blood pressure. This is particularly true for athletes.

Cyclist's Account of Atrial Fibrillation

2010-02-24T12:28:00.001-08:00

I came across this blog entry from John Mandola, MD, a cardiologist who is also an avid cyclist. He describes his experience with an episode of atrial fibrillation (AF), an irregular heartbeat that originates in the upper chambers of the heart.

We've talked about this problem previously here at the blog, but I thought that this cyclist's personal account would hit home about how the patient feels.

The account could also provide some reassurance that, sometimes, AF terminates quickly, a normal heart rhythm is restored, and no further treatment is needed. But it's important to note from the account that the cyclist took the symptoms seriously, went to see the doctor quickly, and was evaluated thoroughly. A good example to follow.

Another Heart Transplant Triathlete

2010-02-24T10:57:00.000-08:00

I came across an interesting article in the print version of Reader's Digest and I see that the article is also available online at www.readersdigest.com.

The article profiles 4 athletes who have overcome major physical adversity. Each of the stories is heart-warming. But the first profile, that of Shannon Kelly, really captured my interest. Selfish interest, I suppose.

Shannon learned as a teenager that she had hypertophic cardiomyopathy and over the years, she became progressively more symptomatic with heart failure. By the time she was in her mid-30's, she was short of breath with only minimal activity. Her only option for treatment was a transplant. The operation went well and she has embraced the "new" life that her transplanted heart has brought.

Two years after her transplant, she took on the challenge of a sprint distance triathlon....and she finished 93rd out of 189. Another remarkable story about a heart transplant recipient.

In the News: Atrial Fibrillation in Cross Country Skiers

2010-02-17T11:42:00.001-08:00

We have talked previously here at the blog about arrhythmias....and specifically about atrial arrhthmias--those that arise in the upper chambers of the heart.

In an interesting study summarized in an article last week at ScienceDaily.com, Norwegian investigators reported on a longitudinal study of cross country skiers, focusing on the development of atrial fibrillation. Starting in 1976, a group of 122 athletes have been followed, with monitoring for the development of arrhythmias. The study is remarkable because of the length (30+ years) of follow-up.

It turns out that, among participants who were alive for the entire period, the prevalence of "lone atrial fibrillation" (that is, without other heart disease) was 12.8%. And this compares to a prevalence of ~0.5% in the general population. Among the athletes with atrial fibrillation, there was also a higher frequency of enlargement of the left atrium and bradycardia (a heart rate <60 beats per minute....a common finding among athletes, anyway).

Other studies have also shown an increased prevalence of atrial fibrillation among endurance athletes. It's not entirely clear yet what the long-term implications might be. And it may well be the case that no specific treatment is needed for athletes who have "lone atrial fibrillation."

I imagine that more information from this study (and commentary, as well) will become available, and I will share anything else I learn.

Athletes and High Blood Pressure

2010-02-05T13:36:00.000-08:00

In a previous blog post, I talked about the general problem of high blood pressure, or "hypertension." Today, I thought I'd focus our discussion about hypertension specifically on the issues that athletes face.

Here at the blog, we've talked about many UNcommon cardiovascular problems that athletes might confront. But hypertension is different. In fact, high blood pressure is the MOST COMMON cardiovascular problem discovered in athletes. If you don't have this problem, you almost certainly know fellow athletes who do. And if you don't have high blood pressure now, you might develop high blood pressure as you age. So....this is a problem worth knowing about.

First, some definitions....and we're talking about adults here....

The NORMAL blood pressure is <120/80.>160/100.

Benefits of Exercise

Randomized clinical trials have shown that physical activity is associated with a decrease in the blood pressure for all patient groups: those who have a normal blood pressure at the outset, those with high normal blood pressure or "pre-hypertension," and those with high blood pressure. Regular and moderate aerobic exercise can reduce the blood pressure by up to 10 mm Hg. Similarly, moderate intensity resistance training (using light weights and high number of reps) can reduce the blood pressure by 3-6 mm Hg.

Regular exercise provides a real benefit. Among the physically active, the risk of developing hypertension is 50% less than for the inactive population. Nonetheless, there will be individuals who DO develop hypertension despite engaging in a regular exercise program. Those at particular risk include: African-Americans, the elderly, the obese, those with diabetes, and those with chronic kidney disease.

Evaluation of the Blood Pressure in Athletes

I've talked several times here at the blog about how important it is for athletes to have a physician. The BP should be checked at every visit. For student athletes, the BP should be checked at a pre-participation physical examination. It is important to remember that the BP varies over time. No single measurement should govern treatment decisions. If the BP is elevated at the doctor's office, it may be wise to re-check the blood pressure in a more relaxed setting such as the home. You may need to work with your physician on how best to do this.

Some behaviors are known to be associated with elevated BP: increased sodium (salt) intake, tobacco use (any form), various over-the-counter medications (cold remedies, decongestants, "diet pills"), ergogenic aids (caffeine, Sudafed, cocaine, human growth hormone (HGH), anabolic steroids), various prescription medications (particularly non-steroidal anti-inflammatory drugs such as Motrin and oral contraceptives), and various dietary supplements.

Treatment of Hypertension in the Athlete

The first approach to treatment will involve "non-pharmacologic" therapy--treatment WITHOUT medications. Since we know the list of "bad" behaviors (noted above), our first efforts should be to eliminate these. We should also note that regular physical activity is helpful in this regard....but if you're reading here, you're probably already an athlete. Other useful measures include: ensuring adequate potassium intake (particularly for endurance athletes) and a variety of relaxation techniques (meditation, yoga, Tai Chi, etc.).

If medications are needed to control an athlete's hypertension, several broad categories of medications are available. Each category has its own benefits and drawbacks. Anything I say here is a simplification, and there is an art and science to the selection of blood pressure medications for a patient. You will need to work carefully with your physician to choose an approach that WORKS FOR YOU.

1. ACE (angiotensin converting enzyme) inhibitors. Examples include: Altace, Zestril, lisinopril, enalapril. May be the drug of choice for athletes. There are few side effects if they are used in individuals who do not have kidney disease. Athletes taking ACE inhibitors may experience a sudden decrease in the BP just after a workout (potentially leading to blackout or syncope), so they should be aware of this possibility and have a cool-down period at the end of each workout.

2. Calcium channel blockers. Examples include: Norvasc, Calan, Isoptin, Cardizem. These medications are also useful in the athlete. They do not lead to a decrease in exercise capacity. They can lead to a decrease in the heart rate and contractility (strength) of the left ventricle (heart's main pumping chamber), but this is compensated for by an increase in the stroke volume (the amount of blood the heart ejects with each heartbeat).

3. ARB's (antiotensin receptor blockers). Examples include: Avapro, Atacand, Cozaar. These medications are similar to the ACE inhibitors. Again, they have a favorable side effect profile.

4. Central alpha-agonists. Examples include: Catapres, Tenex. These medications are not generally useful for the athlete. Side effects include: fatigue, orthostatic hypotension (decrease in the BP related to body position), and fluid and electrolyte imbalances.

5. Diuretics. Examples include: hydrochlorothiazide (HCTZ), Lasix. These should generally be avoided in the athlete. There is an increased risk of heat-related illness, impaired exercise capacity, cramps, and even arrhythmias. In hot weather, these medications may lead to unacceptably high losses of magnesium and potassium.

6. Beta-blockers. Examples include: Inderal, Lopressor, Toprol, Labetalol, Coreg. This is another category of drugs that should generally be avoided in the athlete. They lead to a significant reduction in maximum exercise capacity along with decreased cardiac output and VO2 max. They are also associated with increased perception of exertion and impaired temperature regulation.

Participation Recommendations for Athletes with Hypertension

Prudent recommendations for athletes with hypertension are summarized nicely in a report from the 36th Bethesda Conference on Eligibility Recommendations for Competitive Athletes with Cardiovascular Abnormalities. For athletes with high normal blood pressure or mild hypertension, there should be no restrictions to exercise or sports participation. The blood pressure should be checked every 2-4 months. For athletes with moderate or severe hypertension, activities should be restricted until the blood pressure is controlled.

Banned Substances

The World Anti-Doping Agency (WADA) publishes a listing of medications or other substances that are banned for use by athletes during competition. Athletes should be aware of the ramifications (for their particular sport and circumstance) if they choose, along with their physician, to use medications which are included on the banned list.

Athletes, Sudden Death, and CPR

2010-01-20T10:21:00.000-08:00

In a previous post, "Sudden Death and Cold Weather Marathon," I talked about the unfortunate death of an athlete who was competing in our local Mississippi Blues Marathon a couple weeks ago. There's been a lot of discussion in my circle of friends about the man's death and I've gotten many questions such as "Why did he die?" I thought I'd take the opportunity to talk a little bit about sudden cardiac death (SCD) in general, what we've learned about treating patients who have sudden death, and what lessons might apply to athletes in particular.

The Problem of SCD

Last week, the American Heart Association (AHA) issued a policy statement, published in their journal Circulation, entitled "Regional Systems of Care for Out-of-Hospital Cardiac Arrest." In the United States, there are approximately 295,000 individuals who suffer out-of-hospital cardiac arrest (OOHCA) each year. Of those, only 7.9% are fortunate to be treated and eventually discharged alive from a hospital. It's sobering. And because it's so sobering, the AHA and other organizations devote many resources to improve upon these results.

When we say that individuals have suffered OOHCA, we mean that they have developed a fatal arrhythmia (abnormal heart beat) in the heart, usually ventricular tachycardia or ventricular fibrillation (abnormal rhythms of the pumping chambers). With that type of arrhythmia, the heart no longer pumps blood. Within minutes, the vital organs of the body (particularly the brain) begin to suffer irreversible damage. And the only effective treatment is to restore the heart rhythm to normal in a timely fashion.

The History of Treatment for SCD

We've known for more than 250 years that cardiopulmonary resuscitation (CPR) could be used to help individuals who had suffered cardiac or respiratory arrest. As early as 1740, the Paris Academy of Sciences officially recommended mouth-to-mouth resuscitation for drowning victims. In 1903, Dr. George Crile reported the first successful use of external chest compressions in human resuscitation. In 1963 the AHA endorsed CPR and formed a Committe on CPR chaired by Dr. Leonard Scherlis. And in 1966, the National Research Council of the National Academy of Sciences convened an ad hoc conference on CPR....and led to the recommendation of standardized training and performance standards for CPR (chest compressions and rescue breathing).

Beginning in the 1950's we learned that SCD is typically caused by a fatal arrhythmia and that defibrillation (a shock) could be used to restore the normal heart rhythm. Initially, this was available only in hospitals, but by the 1970's defibrillation could be provided by emergency medical personnel such as paramedics or emergency medicine technicians (EMTs). Continued advancements in technology have allowed for the development of the automated external defibrillator (AED), a device which can record the heart rhythm, interpret the rhythm, and automatically administer a shock of the appropriate type to try to restore the normal heart rhythm. With the advent of the AED, it has become possible for non-medical people to provide life-saving defibrillation at the scene of a cardiac arrest.

As a public health measure, AED's have been recommended and placed in many locations where SCD might occur with increased frequency....airports and other transportation centers, large shopping malls, sports complexes, large industrial sites, golf courses, gyms/health clubs, community centers, etc.

The AHA now sponsors a variety of courses in basic life support, including techniques of CPR and use of the AED. The various courses have target audiences that range from fully trained healthcare providers to entirely non-medical people. Many healthcare organizations require their employees to be trained in basic life support, but most graduates of basic life support training programs are actually non-medical people.

SCD in Athletes

We've talked a little about SCD in athletes previously here at the blog. Indeed, SCD is the most common cause of death in exercising athletes. And this unfortunate event occurs approximately every 3 days in the United States.

Dr. Jonathan Drezner and his colleagues at the University of Washington recently reported an experience in 9 young athletes who suffered sudden cardiac arrest. All 9 had a witnessed collapse and received bystander CPR immediately. A defibrillator was available and used in all 9--within 1.6 minutes when provided by a trainer and within 5.2 minutes when provided by an emergency responder (EMS). Still, only 1 out of 9 athletes who suffered sudden cardiac arrest survived. This experience is typical.

In the world of endurance sports for adult participants, the situation is complicated because of the large geographical area over which these events are conducted. A 5K run doesn't seem so far, but a 26.2 mile marathon or a 140.6 mile Ironman distance triathlon takes the participants far from the immediate reach of medical volunteers or any available AED's or other defibrillators.

Successful treatment of athletes who suffer suddenc cardiac arrest depends on:
1. Prompt recognition that cardiac arrest has occurred.
2. Early bystander CPR.
3. Early defibrillation.
4. Early advanced life support provided by the EMS system.
All four of these components are necessary in order to save the life of an athlete who suffers cardiac arrest. So....when we look back at the issue of "why" an athlete dies during a marathon, the explanation is often found right here.

Some Recommendations

1. As a service to your fellow athletes and community as a whole, learn CPR. Contact the AHA and find an appropriate course in your area.

2. Take the time to check at your local schools and at your local fitness centers to be sure that an AED is available and that on-site personnel are trained in CPR and the use of the AED. These folks may someday be needed to save your life or the life of your child.

3. If you're involved in the planning of endurance sporting events or organized training sessions for endurance athletes, take the time to develop an emergency response plan. Don't be caught off-guard if sudden cardiac arrest occurs.

Hypertrophic Cardiomyopathy Association

2010-01-14T06:24:00.000-08:00

I got a kind email yesterday from Lisa Salberg, the Executive Director of the Hypertrophic Cardiomyopathy Association (HCMA) and thought I'd share some information here at the blog.

I actually met Lisa a couple years ago at a medical conference here in Jackson that was devoted to the topic of sudden death in athletes. My interest in the various issues regarding athletes and heart disease was actually stimulated by that conference.

The HCMA is a non-profit organization that is devoted to providing information and advocacy for patients with hypertrophic cardiomyopathy (HCM), their families, and their physicians. Their website, www.4hcm.org, is a great source of easy-to-read, practical information about HCM and would be a valuable resource for both athletes and non-athletes. Please take a moment to visit their website.

I'll add a link to HCMA in my list of resources.

Cold Weather and Sudden Death in Marathon

2010-01-12T13:10:00.000-08:00

Jackson, Mississippi hosted the 3rd annual Mississippi Blues Marathon this past weekend. The temperatures were bitter cold (17 degrees at the start), but 1,400 or so folks braved the cold to finish the marathon or half marathon events. I twisted my ankle about 10 days ago, or I might have joined my many running friends for the event.

The day was marred by the tragic death of a 40-year-old local man who died in the final mile while he was running the anchor leg for a 5-man relay team. He collapsed suddenly within sight of one of Jackson's major hospitals. He received immediate medical attention, was taken to the hospital, and was pronounced dead. The events are described in this article from the local Clarion-Ledger newspaper. The coroner did not immediately release a statement about the cause of death.

I've received many questions since Saturday about this tragedy and I thought I'd share some of my thoughts here at the blog.

I've talked previously here at the blog about causes of death in middle-aged athletes. Here again, the most likely cause of death is cardiac, and specifically a fatal arrhythmia in the setting of coronary artery disease (CAD). A variety of other causes is possible, though, and we will only learn the true cause when an autopsy is completed. Other possibilities would include undetected hypertrophic cardiomyopathy (HCM), some sort of congenital heart disease, or even catastrophic neurologic event such as a stroke.

I've been asked about the role that the cold temperature on race day might have played in this runner's death. It's an interesting question. Since there are only a handful of deaths annually in the U.S. at marathons, the issue of race-day temperature on the risk of sudden death hasn't really been studied....and probably can't be studied. I recall that it was also a cold day in Detroit this fall when 3 runners died of cardiac causes at the Detroit Marathon. Thankfully, deaths at marathons are rare, at only 1 per ~100,000 runners.

If we think about this problem OUTSIDE the setting of athletic pursuits, it turns out that cold temperatures actually ARE associated with an increased frequency of heart attack. We know this from studies that show that heart attacks occur more often in the winter. And it's generally thought that the cold temperature itself produces some sort of extra stress that might trigger the heart attack. That said, the effect of temperature is relatively small....and heart attacks occur in all temperatures.

We often think about the added stress that HOT or HUMID weather places on athletes in endurance events. But the cold can also add stress. The issues related to cold-weather running are summarized very nicely by Tim Noakes, MD, in his book, Lore of Running, in a section called Cold Hazards. The most important medical concern during cold weather running is hypothermia. And, interestingly, the slower you run (or walk), the more important it becomes to dress warmly.

And lastly, what could have been done to prevent this death? Without more information about his cause of death, I can't be sure. And I don't know anything about this runner's medical history or preparation for the event. Perhaps nothing could have been done. But I've said it here at the blog before....if you're a 40-year-old endurance athlete, it is wise to have a physician, get screened for possible unrecognized heart disease, and treat all warning signs such as chest pain or unusual shortness of breath seriously. Get checked out. And make certain that your goal event makes sense in the context of your medical condition and your athletic preparation for the event.

In the News: Link Between Peripheral Artery Disease (PAD) and Coronary Artery Disease

2010-01-08T10:44:00.001-08:00

We've talked previously here at the blog about coronary artery disease (CAD), and we've talked about several important risk factors.

Earlier this week in Science Daily, there was an article entitled "Severe Asymptomatic Heart Disease May Accompany Narrowing in Leg Arteries." The article reports on a recent study from the Netherlands which points out the important association between peripheral artery disease (PAD)--blockages in the arteries of the legs, that can produce pain or discomfort while exercising--and CAD.

Individuals who are found to have PAD should be checked carefully for co-existing CAD.

In the News: Hidden Benefits of Exercise

2010-01-08T08:36:00.000-08:00

A while back, I wrote about the athlete's cardiac paradox. I pointed out that there were many benefits of regular exercise, but that the exercise itself puts some athletes at increased risk for sudden death.

I came across an article in the Wall Street Journal earlier this week entitled "The Hidden Benefits of Exercise." I enjoyed reading the article because it pointed out some health benefits of exercise that I hadn't thought much about.

I thought you'd enjoy reading the article, too.

Some Useful Resolutions

2010-01-01T17:35:00.000-08:00

Happy New Year!

I'm not usually a fan of New Year's resolutions. You know the problem. There's usually a lot of talk in late December and early January....and all too little action for the rest of the year.

But I suppose this is as good a time as any to change direction or improve one's course in life. For those who are interested (and this should probably be EVERY athlete), here are my thoughts about some useful, practical resolutions for the new year....for your heart health....that I've culled from our discussions these past 4 months.

1. Take charge. Become knowledgeable about your cardiovascular health. We'll continue to explore a variety of issues here at the blog and I'll be sure to point out other web-based and print resources that may be useful particularly to athletes.

2. Put a doctor on your team. I've talked here at the blog about the issue of "Who Needs a Doctor?" Your team ought to include a variety of resources....a coach, a confidant, training partners, a massage therapist, etc. Don't leave out the doctor. A long-term relationship with a physician will provide many benefits over the years, I promise!

3. Get screened for cardiovascular disease. Work with your doctor to get screened for the common cardiovascular problems that may cause sudden death in athletes. Talk with your doctor about getting an ECG and an echocardiogram.

4. Work with your doctor, especially as you enter your 30's or 40's, to manage your risk factors for coronary artery disease (CAD). This is the most important heart-related problem for athletes in middle age.

5. Eat right. There are probably many ways to go about improving your diet. We've talked here at the blog about the Mediterranean Diet, but that's just one approach. For the past 18 months, I've been suggesting the "Real Food Diet" to my patients and friends. The idea came from my friends at Endurance Corner. Put simply, just: 1) eat real food (lean proteins, fruits, vegetables, products at the store with fewer than 5 ingredients); 2) avoid pasta; and 3) avoid refined sugar after 2 pm. Keeping it simple will make it workable for many athletes.

This is a short list, but doing just these few things now....and for years to come....will make a big difference in your risk for developing heart and vascular disease.

Let's build a healthier 2010 together. Happy New Year!

Reggie Lewis, NBA player, 1965-1993

2009-12-28T07:08:00.000-08:00

Reggie Lewis, a superstar NBA player with the Boston Celtics, died at the age of 27 on July 27, 1993. He collapsed suddenly during an off-season practice at Brandeis University and received bystander CPR, but was pronounced dead at a local hospital a couple hours later. The cause of his death was attributed to hypertrophic cardiomyopathy (HCM), a condition characterized by hypertrophy (enlargement) of the heart walls and a susceptibility to potentially lethal arrhythmias (abnormal heartbeat).

There's an interesting twist to Lewis's story, though. It turns out that 3 months earlier, he passed out during an NBA playoff game against the Charlotte Hornets on April 29, 1993. He was evaluated by a prominent group of cardiologists at the New England Baptist Hospital and was diagnosed with HCM. Those doctors admitted that there was often some difficulty in distinguishing HCM from the "athlete's heart syndrome," the normal enlargement of the heart due to cardiovascular training, but they recommended that Lewis no longer play basketball.

Lewis sought additional opinions, first from physicians at the Brigham & Women's Hospital in Boston and later at UCLA. The cardiologists at Brigham & Women's Hospital felt that Lewis did not have HCM, but rather had collapsed from a relatively harmless condition known as neurogenic syncope. The doctors at UCLA weren't able to reach a definitive diagnosis.

We can understand why any professional athlete would be conflicted with the recommendation that he no longer play, but as we know now, the result was tragic.

This story illustrates the common scenario of sudden death in athletes who, unknowingly, have HCM....and illustrates the common problem that HCM can be difficult to distinguish from "athlete's heart syndrome."

What should I write about next?

2009-12-21T07:26:00.001-08:00

It's Christmas week, so let me wish you all a safe and happy holiday.

And let me also thank you for stopping by the blog. I've appreciated the many comments and suggestions along the way these past few months.

Much of what I've written about has been motivated by questions I've gotten from friends and readers. And that works well because it keeps things relevant. I'm still working gathering information about the topics listed to the right.

But this is your chance....

Please let me know what you'd like to read and learn about in the weeks ahead. Just submit a comment here or email me at the address to the right.

Again, Happy Holidays! Back in the New Year....

An Aspirin a Day?

2009-12-18T07:03:00.000-08:00

Today, we'll talk about aspirin....and whether you might benefit from taking a daily aspirin tablet.

First, a little about aspirin itself. It's complete name is acetylsalicylic acid, or ASA for short. It comes in a variety of sizes, but the most common are 81 mg (the "baby" aspirin) and 325 mg (the standard dose). Aspirin is used for a variety of purposes, including as an analgesic (pain reliever), an anti-pyretic (relieves fever), and as an anti-inflammatory medication. The main unwanted side effect of aspirin is a small risk of stomach bleeding.

Today, we'll focus on the use of aspirin to prevent adverse events such as heart attack, stroke, or vascular disease.

Individuals who already have cardiovascular disease (CVD)

For people who already have cardiovascular disease (of almost any sort), aspirin has been shown in many studies (involving 10's of thousands of patients) to reduce the chance of having heart attack, stroke, or new vascular disease. We call this "secondary prevention"--preventing a "second" problem. If you fit into this category, you should talk with your doctor about taking aspirin or other similar medication.

Individuals who DO NOT have cardiovascular disease (CVD)

For this group of people, recommendations about aspirin use are a little more complicated. We call this "primary prevention"--preventing the first episode of important CVD.

If we look at this entire group of healthy people, aspirin HAS NOT been shown convincingly to reduce the chances of developing important CVD, but.... It turns out that for SOME healthy people--those with a somewhat elevated risk (based on risk factors) of developing CVD at some point--aspirin actually does provide a benefit. So....the issue becomes sorting out which people benefit and which people do not.

This is where my previous Blog Post comes into play. You should use the worksheets and tables (separate worksheets and tables for men and women) to determine your 10-year risk of developing CVD. Many of you will find that that risk is nearly zero, but you'll also see that the presence of any risk factor can elevate that risk substantially.

The American Heart Association recommends daily aspirin for patients whose 10-year risk of CVD is >=10%. That's pretty easy. But there may be good reason to use daily aspirin even if your risk is less than that. A useful algorithm for making decisions about daily aspirin for primary prevention was published in the 2007 Guide to Clinical Preventive Services by the Agency for Healthcare Research and Quality (AHRQ):

"Men older than 40 years, postmenopausal women, and younger people with risk factors (eg, hypertension, diabetes, or smoking) are at increased risk for heart disease and may wish to consider aspirin therapy."

I believe this is a useful approach. If you are healthy and have ANY risk factor for CVD, you should discuss the potential benefits of daily aspirin therapy with your doctor.

How much aspirin?

It turns out that a daily baby aspirin (81 mg) is probably just as effective as the standard dose (325 mg)....and may reduce the chances of having stomach bleeding.

So, to summarize.... Daily aspirin use is effective for secondary prevention. It is also effective for primary prevention in some patients, particularly those with risk factors for CVD. It is wise to discuss the benefits and risks of aspirin with your doctor before starting this medication, though, because there is a very real risk of unwanted stomach (or other) bleeding. And lastly, a baby aspirin is probably the right dose for most people.

What is YOUR Risk?

2009-12-17T07:41:00.001-08:00

I’ve gotten a couple questions recently from athlete friends about using aspirin to help prevent heart disease. Just before I started the Athletes Heart Blog, I had some discussion with my triathlon friends about this issue, and I thought I’d share my thoughts with a broader audience here.

Later this week, in a separate blog post, I’ll talk about aspirin specifically.

But first….we need to talk about your risk of developing coronary heart disease (CHD). And by this, I mean the collection of clinical problems caused by coronary artery disease (CAD)—sudden death, heart attack, angina—that I discussed in a previous blog post. It’s important to know YOUR personal risk for the development of CHD because the effectiveness of drugs (or other treatments) in PREVENTING you from developing CHD depend very much on your inherent RISK.

Over many decades, data have been collected by the Framingham study on a very large number of Americans about their health and lifestyle habits. One byproduct from this large database has been the development of equations that can be used to predict your 10-year risk of developing CHD.

Use the “worksheets” below to tally up points for your LDL score and your Chol score. When you’ve tallied up the points, you’ll use the appropriate table to determine your 10-year risk of CHD. We need to consider men and women separately because the risks are different….and so there are separate “worksheets” and tables for men and women.

Now you’ll know YOUR risk. This is an important number and you should talk about this with your doctor when you visit.

Next time, we’ll talk about whether aspirin can reduce your risk of CHD. And we’ll be able to talk about other prevention strategies as well. Check back later this week.

FOR MEN

Step 1. Age

Years
30-34: LDL score = -1; Chol score = -1.
35-39: LDL score = 0; Chol score = 0.
40-44: LDL score = 1; Chol score = 1.
45-49: LDL score = 2; Chol score = 2.
50-54: LDL score = 3; Chol score = 3.
55-59: LDL score = 4; Chol score = 4.
60-64: LDL score = 5; Chol score = 5.
65-69: LDL score = 6; Chol score = 6.
70-74: LDL score = 7; Chol score = 7.

Step 2. Serum lipid levels

LDL cholesterol (mg/dL)
<100: LDL score = -3.
100-159: LDL score = 0.
160-190: LDL score = 1.
>=190: LDL score = 2.

Cholesterol (mg/dL)
<160: Chol score = -3.
160-199: Chol score = 0.
200-239: Chol score = 1.
240-279: Chol score = 2.
>=280: Chol score = 3.

HDL cholesterol (mg/dL)
<35: LDL score = 2; Chol score = 2.
35-44: LDL score = 1; Chol score = 1.
45-54: LDL score = 0; Chol score = 0.
>=55: LDL score = -1; Chol score = -2.

Step 3. Blood pressure (check your score for systolic and diastolic blood pressures, but use ONLY the highest score, not both)

Systolic pressure (top number, mmHg)
<120: LDL score = 0; Chol score = 0.
120-129: LDL score = 0; Chol score = 0.
130-139: LDL score = 1; Chol score = 1.
140-159: LDL score = 2; Chol score = 2.
>=160: LDL score = 3; Chol score = 3.

Diastolic pressure (bottom number, mmHg)
<80: LDL score = 0; Chol score = 0.
80-84: LDL score = 0; Chol score = 0.
85-89: LDL score = 1; Chol score = 1.
90-99: LDL score = 2; Chol score = 2.
>=100: LDL score = 3; Chol score = 3.

Step 4. Diabetes

No: LDL score = 0; Chol score = 0.
Yes: LDL score = 2; Chol score = 2.

Step 5. Smoker

No: LDL score = 0; Chol score = 0
Yes: LDL score = 2; Chol score = 2

FOR WOMEN

Step 1. Age

Years
30-34: LDL score = -9; Chol score = -9.
35-39: LDL score = -4; Chol score = -4.
40-44: LDL score = 0; Chol score = 0.
45-49: LDL score = 3; Chol score = 3.
50-54: LDL score = 6; Chol score = 6.
55-59: LDL score = 7; Chol score = 7.
60-64: LDL score = 8; Chol score = 8.
65-69: LDL score = 8; Chol score = 8.
70-74: LDL score = 8; Chol score = 8.

Step 2. Serum lipid levels

LDL cholesterol (mg/dL)
<100: LDL score = -2.
100-159: LDL score = 0.
160-190: LDL score = 2.
>=190: LDL score = 2.

Cholesterol (mg/dL)
<160: Chol score = -2.
160-199: Chol score = 0.
200-239: Chol score = 1.
240-279: Chol score = 1.
>=280: Chol score = 3.

HDL cholesterol (mg/dL)
<35: LDL score = 5; Chol score = 5.
35-44: LDL score = 2; Chol score = 2.
45-49: LDL score = 1; Chol score = 1.
45-54: LDL score = 0; Chol score = 0.
>=55: LDL score = -2; Chol score = -3.

Step 3. Blood pressure (check your score for systolic and diastolic blood pressures, but use ONLY the highest score, not both)

Systolic pressure (top number, mmHg)
<120: LDL score = -3; Chol score = -3.
120-129: LDL score = 0; Chol score = 0.
130-139: LDL score = 0; Chol score = 0.
140-159: LDL score = 2; Chol score = 2.
>=160: LDL score = 3; Chol score = 3.

Diastolic pressure (bottom number, mmHg)
<80: LDL score = -3; Chol score = -3.
80-84: LDL score = 0; Chol score = 0.
85-89: LDL score = 0; Chol score = 0.
90-99: LDL score = 2; Chol score = 2.
>=100: LDL score = 3; Chol score = 3.

Step 4. Diabetes

No: LDL score = 0; Chol score = 0.
Yes: LDL score = 4; Chol score = 4.

Step 5. Smoker

No: LDL score = 0; Chol score = 0.
Yes: LDL score = 2; Chol score = 2.

In the News: Do Your Kids Have Heart Disease?

2009-12-11T06:38:00.000-08:00

I came across an article in last week's online edition of the Houston Chronicle, entitled "Sixth-graders' heart screenings shock researchers," and I thought you might find it interesting.

There has been a fair amount of research devoted to the issue of pre-participation physical examinations for school-aged children who want to play school sports. The goal of these efforts has been to identify students who are at particularly high risk for cardiac or other events....and either provide necessary treatment or exclude the children from participating.

A group of investigators in Houston, led by John Higgins, M.D., has begun to screen 1,500 middle school age children--all students, not just athletes--for heart disease using a 20-minute screening procedure. The students underwent a health history, physical exam, ECG, and echocardiogram.

After evaluating the first 94 students at a single middle school, the investigators were surprised to find that 7 students had significant heart disease....and 2 required surgery for treatment of their condition! Some of these conditions would typically produce no outward signs or symptoms....and the first indication of a problem could have been sudden death.

When it is completed, this study will be the most comprehensive look at the benefits of a cardiac screening program for U.S. children and I suspect it will influence the way we go about pre-participation screening for school-aged athletes.

In the News: Why Do Athletes Live Longer?

2009-12-08T08:51:00.000-08:00

I came across an interesting article in the November 30th edition of U.S. News & World report online and thought I'd share it with you here. It's interesting reading.

There is an abundance of data that indicate beneficial effects of exercise....and one of those benefits may be a longer life-expectancy. But why?

Last week, in the online version of Circulation, an American Heart Association medical journal, a group of investigators in Hamburg, Germany report some novel findings in young and middle-aged track and field athletes in an article, entitled "Physical exercise prevents cellular senescence in circulating leukocytes and in the vessel wall."

It turns out that endurance athletes have longer telomeres--the DNA at the tips of the chromosomes that protect cells--in their white blood cells compared to non-athletes. The authors speculate that this feature provides, over a lifetime, an anti-aging effect.

It's also interesting to note that three American scientists shared the Nobel Prize in Medicine this year for their work, over many years, to understand the telomeres and the process of cell death and aging. You can read about this in a report at cnn.com from earlier this week.

Scientists are only beginning to understand the process of aging in humans, but it is nice to know that endurance athlete's may have a leg up!

Do You Have "Athlete's Heart"?

2009-12-06T12:19:00.001-08:00

Do you have "athlete's heart"?

If you're a well-trained endurance athlete, you probably do. And don't even know it. But that's okay, because "athlete's heart" is generally a good thing. Here's why....

We've known for more than a century that there are a variety of cardiac changes that are associated with exercise. As long ago as 1899, S. E. Henshen at the University of Uppsala Sweden published a report entitled, "A Study in Sports Medicine; Skiing and Competitive Skiing," recognizing that skiers developed enlarged hearts that were a response to exercise. And we've learned a lot more during the past 100 years about the heart's adaptation to exercise.

Today, we use the terms, "athlete's heart" or "athlete's heart syndrome" to refer to the entire collection of the heart's physiological adaptations to exercise. Those adaptations come in 2 main forms: structural changes and electrical changes.

Structural changes

Over time, the well-trained athlete's heart adapts in order to provide a high cardiac output (volume of blood pumped per unit of time) in the most efficient manner. Because of mechanical advantage (after all, the heart is only a pump), the heart adapts by increasing the volume of its chambers, decreasing its heart rate, and increasing the thickness of the heart's muscular walls--particularly the ventricles (the pumping chambers).

Changes in the structure of the heart will not be the same for every athlete. These changes will be most pronounced for athletes who engage in the aerobic sports (running, swimming, cycling, rowing, etc.).

The thickness of the left ventricular wall is usually less than 1.3 cm in thickness, with many individuals having a thickness of 1.0 cm or so. Well-trained athletes may have a left ventricular wall thickness of up to 1.5 cm, again an adaptation that helps with the generation of additional cardiac output during exercise.

Electrical changes

Athletes can have a variety of electrical changes that show up on an ECG. The most common finding is a slow heart rate (that we call "bradycardia" when the heart rate is less than 60 beats per minute). You'll know that you and your athletic friends may have a resting heart rate that is much less than even 60 beats per minute. Yet the medical profession arbitrarily calls 60 to 100 beats per minute "normal"....for most individuals. For the well-trained athlete, though, a heart rate less than 60 beats per minute is typical and simply reflects the efficiency that the heart has developed over time due to exercise.

There are many other findings that can be present on the athlete's ECG, including sinus arrhythmia, wandering atrial pacemaker, first- and second-degree heart block, junctional rhythm, and various types of repolarization abnormalities. These terms will only be meaningful to a medical professional, but suffice it to say that, when we add up the frequencies of all of these findings, an athlete's ECG is very often "abnormal."

Physical examination

In addition to the structural and electrical changes, there can be changes in the physical examination, as well. Athletes are more likely than non-athletes to have murmurs or other heart sounds (heard by stethoscope) that are simply a manifestation of the structural and electrical changes mentioned above.

Why is this important?

I've said that all of these changes, or adpations, are a good thing. And they are! But here's the problem....

Imagine this scenario. And it's pretty typical. A 42-year-old man, an avid triathlete, crashes while cycling, fractures his clavicle, and requires operation for repair of the clavicle fracture. He gets an ECG before the operation to screen for any unrecognized heart problems....and behold, he has an abnormal ECG. His physicians overlook the fact that the "abnormal" ECG may be very "normal" for an endurance athlete....and they order a variety of (possibly unneeded) additional heart tests to look for any specific heart disease. And, in the end, they don't find anything wrong.

It's important for you and your physicians to remember that you're an athlete and that you may have features of the "athlete's heart syndrome." The next time you're at the doctor's office and he or she is listening to your heart with a stethoscope, you might ask the doctor if there was a murmur. Mention that you've learned something about athlete's heart syndrome and ask if any murmur might be due to that. You'll impress your doctor....and you'll be helping your doctor remember that athlete's are special.

This another area where you can be as knowledgable (or perhaps more knowledgable) than your doctor. Take charge.

In the News: Forecasting the Effects of Obesity and Smoking on U.S. Life Expectancy

2009-12-03T10:20:00.001-08:00

In today's issue of The New England Journal of Medicine, a group of investigators headed by the Harvard University Interfaculty Program for Health Systems Improvement have issued a report entitled, "Forecasting the Effects of Obesity and Smoking on U.S. Life Expectancy."

The investigators examined data collected by 3 large-scale survey projects: the National Health Interview Survey, the National Health and Nutrition Examination Survey, and the Medical Expenditure Panel Survey.

Over the past 30 years, there has been a decline in smoking rates in the U.S., leading to improvements in our overall health. Unfortunately, there has also been a steady rise in the rate of obesity in our society. Indeed, more than one half of the U.S. population are likely to meet the World Health Organization (WHO) definition for obesity by the year 2020.

It has previously been estimated that obesity now accounts for between 5% and 15% of deaths each year in the United States and that smoking accounts for 18%. Moreover, if smoking were eliminated, it is estimated that the population life expectancy would increase by as much as 1 to 2 years.

The authors conclude that if current trends in obesity continue, the negative effects from the obesity epidemic will outweigh any positive effects of continued declines in the rate of smoking in this country.

Reference: Stewart ST, et al. Forecasting the effects of obesity and smoking on U.S. life expectancy. N Engl J Med 2009;361:2252-60.

In the News: Acute Effects of Marathoning on the Heart

2009-12-02T12:42:00.001-08:00

At last month's annual scientific meeting of the American Heart Association, investigators from the William Beaumont Hospital in Royal Oak, Michigan, reported on a small study of runners who participated in the 2008 Detroit Marathon.

The abstract for their presentation was published in the Abstract Book for the meeting and their findings are also summarized in this article from ScienceNews online.

There has long been the concern that there is acute (and possible long-lasting) heart damage in amateur runners who participate in marathon events. The study participants underwent blood tests, a cardiac MRI scan, and 24-hour Holter monitoring (tape recording of the ECG) 4 weeks before and then immediately after the marathon. The authors reported that, although there is release of a small amount cardiac enzymes into the bloodstream (indicating potential heart stress) during and immediately after a marathon, there is no evidence of damage per se to the heart. They also confirm the findings of many previous investigators that there is mild to moderate enlargement of the right atrium and right ventricle when they are measured immediately after the marathon. These changes are thought to resolve within 3 to 6 months after the event.

The detailed findings from this study probably won't appear in medical journal for a year or more, but long-distance runners should take some comfort from this report.

In the News: Detroit Marathon Deaths

2009-12-01T13:48:00.000-08:00

In a report today from the Detroit Free Press, we learned that the deaths of the 26-year-old and 36-year-old runners in the recent Detroit Marathon were due to cardiac causes. Although the report does not go into very much medical detail, the immediate cause of death for both was reported to be "cardiac dysrhythmia"--an abnormal, ineffective heartbeat--due to "heart attack."

The Detroit Free Press reported a couple weeks ago about the death of the 62-year-old athlete, saying that his death was also due to "heart disease."

I'll post again here if more details become available about the specifics of these runners' heart disease are made available.

Follow on Twitter

2009-12-01T12:20:00.000-08:00

You can now follow the Athlete's Heart Blog on Twitter....

www.twitter.com/athletesheart

....and receive a tweet with each new posting at the blog.

This was a suggestion from a reader....and a good one! This blog has only been up and running for about 10 weeks now and I'm still learning. Keep the suggestions coming.

Useful Article: 8 Ways to Prevent Heart Disease

2009-11-30T10:52:00.000-08:00

I ran across this article (actually I received a Tweet about it) last week from active.com. The article elaborates a little bit on the 6 risk factors for CAD that I mentioned previously that are within your control.

The article also mentions 2 additional ways to help reduce your risk of CAD:
1. Consider a drink a day and
2. Consider low-dose aspirin.

Both of these additional suggestions are good ones. In upcoming posts, we'll talk in more detail about all of these risk factors and suggestions for reducing your risk of CAD.

In the News: Cardiac Screening for High School Athletes

2009-11-24T08:07:00.000-08:00

At last week's meeting of the American Heart Association, a group of investigators from Johns Hopkins University School of Medicine presented their findings about rigorous pre-participation cardiac screening in a small group of high school athletes. Their detailed findings probably won't appear in a medical journal for a year or more, but this article at sciencedaily.com summarizes the results.

The screening process included a physical examination, an echocardiogram, and an EKG. Although the authors did not find any life-threatening abnormalities among the 134 athletes studied, they did find significant abnormalities in 36 of the athletes that required further evaluation.

The authors concluded that the addition of an echocardiogram and EKG was important in this population.

Coronary Artery Disease: The Essentials

2009-11-21T17:11:00.001-08:00

For those of you who have been following along, we've talked briefly before about the problem of coronary artery disease (CAD) and illustrated the problem last week with the story of Jim Fixx. And I've mentioned previously that CAD is the most common cause of sudden death in athletes over the age of 40. Today, we'll talk about CAD in a little more detail. This should provide the foundation for future discussions that we'll have about the many aspects of maintaining heart health as we age.

To put the problem of CAD into some perspective, you should realize that this is the most important chronic medical condition that Americans face. In fact, CAD affects more than 13 million Americans today. It's the leading cause of death in the United States, with nearly 1 person dying every minute from this condition.

The Anatomy

The heart, as you know, is simply a muscle....but one that is in constant motion, usually beating 60-100 beats each minute, or upwards of ~140,000 times each day. And like other muscles of the body, it requires a generous blood supply to furnish the needed oxygen to keep things going. As the aorta leaves the heart, to take blood flow to the rest of the body, the first 2 branches are the left and right coronary arteries....the arteries that supply blood flow to the heart muscle itself. The left coronary artery branches into the left anterior descending and the circumflex coronary arteries. We often say, then, that there are 3--not 2--important coronary arteries.

We use the term CAD to refer to the progressive (over many years time) narrowing of the coronary arteries, the arteries that supply the heart muscle with its blood supply. This process, called atherosclerosis, usually starts with fatty streaks on the inside surface of the coronary arteries, but over years' time progresses to larger, more space-occupying deposits of various lipids. The situation is not much unlike a typical plumbing problem, where a pipe might become clogged with unwanted material, thereby limiting blood flow.

What problems does CAD cause?

Individuals with CAD often experience no problems until the narrowing in the coronary arteries becomes severe. When the arteries become narrowed to less than 25-50% of their original diameter, the reduction in blood flow to the heart muscle can produce symptoms. At first, the symptom might be chest pain or discomfort (that we call "angina") or perhaps unusually severe shortness of breath with exertion. Any of these symptoms should be a warning sign....and prompt you to be evaluated by your physician.

The plaques on the inside of the coronary arteries can sometimes rupture, leaving a raw surface exposed to the bloodstream, and lead to the formation of a blood clot at that site. This can produce chest pain at rest (unstable angina) or even acute myocardial infarction (MI), the situation where there is irreversible damage to the heart muscle.

Who gets CAD? What are the risk factors?

Much time and effort has been devoted to understanding who gets CAD. As you can imagine, this is the starting point for figuring out how to prevent CAD. We've learned that there are a handful of so-called risk factors, indicators of how likely it is that an individual will develop CAD. Some of these risk factors can't be changed, but others can be modified to help reduce somebody's risk.

There are some risk factors that you simply can't change. One such risk factor is age. Men over the age of 45 and women over the age of 55 are more likely than their younger counterparts to have CAD. Unfortunately for men, men are just more likely than women to have CAD. And lastly, a family history of CAD in close relatives is a risk factor. As you can see, each of these risk factors is beyond your control.

On the bright side, though, several risk factors are under your control....and should be paid very special attention as we age:

1. Obesity (or even just being overweight)

2. High blood pressure

3. Smoking

4. High levels of blood cholesterol

5. Diabetes

6. Physical inactivity (although I'll bet that most readers here are active!).

We'll cover these risk factors in greater detail in upcoming posts.

Diagnosis and Treatment

Most patients with CAD come to medical attention because of symptoms such as angina or shortness of breath. Many others come to attention because of acute MI. And, sadly, some come to attention because of sudden death....and an autopsy shows CAD.

A stress test (which can be done in a variety of ways) or a cardiac CT scan can indicate the likelihood of CAD. The diagnosis is established, though, with coronary arteriography....a test in which dye is injected into the coronary arteries and motion picture x-rays are made. This creates a roadmap of the coronary arteries and shows any blockages.

If blockages in the coronary arteries are not severe, patients can be treated with medicines. Patients with severe blockages can be treated with angioplasty and stenting (to push the blockages aside) or with coronary artery bypass surgery.

That's CAD in a nutshell. Like I said, I hope that this information provides the necessary foundation for us to have more detailed discussions about various topics down the road.

Jim Fixx, Runner, 1932 - 1984

2009-11-16T15:25:00.000-08:00

Here at the blog, we've talked about a variety of cardiovascular diseases that affect athletes. Coronary artery disease, that can lead to heart attack, is the most common cause of sudden death in athletes over the age of 40.

Years after his death, many will remember Jim Fixx for the contribution he made to the popular enjoyment of running. His story is very compelling. In his mid-thirties, he was overweight (240 pounds), a 2-pack-a-day smoker, and sedentary. But he got the urge to do something healthier....and took up running at age 35. He would lose more than 60 pounds and became an example of how a healthier lifestyle was possible for ordinary folks.

In 1977, Fixx authored "The Complete Book of Running." At the time, this was the best-selling non-fiction hardcover book ever published. He inspired countless Americans to take up the hobby of running.

Out for a run through the Vermont countryside on July 20, 1984, Fixx was found alongside the road, dead at the age of 52. An autopsy showed that he had severe blockages in all 3 of his coronary arteries....a setup for heart attack or sudden death.

On the face of it, Fixx's death was stunning. His public persona was the picture of health. Yet we know that at the time of his death he didn't have a personal physician. In fact, he hadn't had a physical examination in years....despite his history of obesity and smoking. Moreover, he had a strong family history of coronary artery disease in his family: his father had his first heart attack at age 35 and died of his second heart attack at age 43.

We'll never know if Fixx's death was avoidable....but his story provides lessons for all of us middle-aged athletes who are pounding the pavement each day.

In my next post, I'll talk about the problem of coronary artery disease, along with its risk factors, prevention, and treatment. And I promise to leave our readers with some useful advice on what they can do to prevent a story like Fixx's.

In the News: Preventing Sudden Death in Athletes

2009-11-12T07:02:00.000-08:00

Saw this article last week at U.S. News & World Report online, entitled "Determining the best way to prevent sudden death in athletes."

The article summarizes some data about the problem of sudden death in athletes and makes several suggestions for athletes:
1. Get screened for heart problems. See the doctor.
2. Pay attention to your body and any potential warning signs. Get checked out if you have problems with chest pain, shortness of breath, light-headedness (or blacking out)
3. Check to be sure your local gym has an automatic external defibrillator....it could save your life.

All of these are great suggestions.

In the News: Pre-participation Screening for Student Athletes

2009-11-03T10:21:00.001-08:00

Another interesting article, in Athletic Business, about pre-participation screening for student athletes. Nice summary of the issues and mentions the success in Italy for more detailed screening programs in Italy. This issue is getting more attention.

In the News: Runners' Heart Woes

2009-11-02T14:30:00.001-08:00

A short article at SFGate (San Francisco Chronicle) shares some information about cardiovascular risks associated with running....and again suggests the value in careful pre-participation screening. Another article that relates to my previous post, "Who Needs a Doctor?"

In the News: Sudden Cardiac Death

2009-11-02T14:23:00.000-08:00

I came across an informative article about sudden cardiac death (SCD) in the online edition of the Halifax Evening Courier. The article focuses on the recent death of Boyzone singer Stephen Gately, but the content relates to the risk of SCD in young athletes as well. The article points to the need for careful screening examinations for cardiovascular disease and this fits in well with my previous post, "Who Needs a Doctor?"

Who Needs a Doctor?

2009-11-01T16:39:00.001-08:00

One of the most frequent questions I receive takes the form of:

"Should I see a doctor?

"How often should I see a doctor?"

If you've been reading here at the blog, you know that athletes take on special cardiovascular risks just by participating in their sports activities. And for that reason, they should see a doctor before they participate. The hope is that a careful physician can screen for potential underlying cardiovascular problems that might place the athlete at risk. And all of this is on top of the many other benefits that a careful physician might provide.

Here's what I tell my friends who ask....

Student athletes

For middle school, high school, and college students who participate in athletics, their schools should provide guidelines about pre-participation physical examinations. The American Heart Association has developed guidelines to help physicians carefully screen for underlying cardiovascular conditions. The guidelines are written for medical professionals, so the text may be difficult for others to understand. In short, the AHA recommends that student athletes have a physical examination every 2 years during middle and high school and every year during college. Middle and high school students should have a careful medical history taken EVERY year, even if a physical examination is not performed.

The medical history should ask about:

1. Any chest pain or discomfort

2. Unexplained syncope or near syncope (blacking out or nearly blacking out)

3. Excessive shortness of breath during exertion

4. Previous recognition of a heart murmur

5. Elevated blood pressure

6. Family history of premature death (before 50 years) due to heart disease

7. Family history of disability due to heart disease in a relative younger than 50 years old

8. Family history of specific medical problems: Marfan syndrome, hypertrophic or dilated cardiomyopathy, long Q-T syndrome, or arrhythmias

The physical exam should pay attention to:

1. Heart murmur

2. Femoral pulses (to exclude coarctation of aorta)

3. Physical signs of Marfan syndrome

4. Blood pressure

Any abnormalities uncovered with this checklist should be evaluated further.

Young adult athletes, up to age 35

The AHA guidelines are probably also useful for young adult athletes. I tell my friends in this age group that they should see a physican yearly for a careful medical history and physical examination. The checklist for cardiovascular conditions above is also useful in this age group. This is also the age group where a baseline check on blood cholesterol and lipid levels and routine blood chemistries (glucose, creatinine, etc.) should be made.

Older adult athletes, over age 35

As athletes age, they confront an ever-increasing risk of events due to coronary artery disease (CAD, where plaque builds up in the arteries that supply the heart). A yearly visit to the physician for a medical history and physical examination is increasingly important. This is the age range when it is important, even aside from athletic reasons, that people should establish a long-term relationship with a family or internal medicine physician. In this age group, many female athletes will already see a physician regularly for gynecologic or obstetrical care, but "healthy" men are notoriouis for avoiding the doctor. The physician should continue to screen on a periodic basis for the risk factors for CAD: smoking, high blood pressure, obesity, diabetes or pre-diabetes, elevated blood cholesterol or lipids, and potentially others.

Athletes of any age, with medical problems

My suggestions above apply only to "healthy" athletes....those with NO chronic medical conditions. Athletes with ANY chronic medical condition will need to work with their physician to determine the frequency of visits to monitor those conditions. This will almost certainly require more than a single annual visit to the doctor.

Aortic Stenosis and Bicuspid Aortic Valve

2009-10-27T11:25:00.000-07:00

I operated on a young man (in his early 30’s) a couple weeks ago for aortic valve replacement. It reminded me that valvular heart disease is not limited to older folks. This particular patient wasn’t an athlete, but I have a cycling acquaintance here in Jackson who also needed aortic valve replacement in his 30’s.

The aortic valve is the valve that lets blood flow out of the heart, from the left ventricle (the heart’s main pumping chamber) into the aorta (the large blood vessel that carries blood to the rest of the body). Ordinarily, this valve has 3 leaflets that are arranged to produce a pattern much like the Mercedes Benz emblem, if you look at the valve from above. With each heartbeat, the leaflets open nearly completely, allowing for unobstructed blood flow out of the heart.

There are 2 main problems that happen with heart valves….the valve can leak or it can become obstructed. Today, we’re going to focus on narrowing of the aortic valve, that produces obstruction to blood flow, and this is a condition that we call aortic stenosis. We’ll leave the leaking valves to another day.

There are several causes of aortic stenosis, but, by far, the most common cause is age-related calcific degeneration of the valve. That is, over years and years, calcium deposits build up in the valve leaflets, making them immobile. The leaflets eventually become so stiff that they do not open properly….and produce obstruction to blood flow exiting the heart. Aortic stenosis is usually a problem for patients who are in their 60’s, 70’s, or even older. Because the problem develops gradually over many years, patients sometimes don’t notice the effects, but the 3 primary symptoms are: 1) shortness of breath with exertion; 2) chest pain; and 3) syncope (blacking out).

Patients come to medical attention because of one or more of the hallmark symptoms or occasionally because a physician hears a heart murmur. There is a characteristic sound, or murmur, associated with aortic stenosis and your physician can hear this murmur in a very particular location on the chest—just to the right of the sternum, above the level of the nipples. An echocardiogram (ultrasound) is used to make detailed pictures of the heart valves and can be used to quantify the degree of stenosis, or obstruction, as mild, moderate, severe, or critical.

Aortic stenosis is a serious medical problem. Patients with severe or critical aortic stenosis require valve replacement. There is no other treatment (ie, medicines) that can correct the problem. For patients with breathing difficulties because of their aortic stenosis, the average life-expectancy is less than 2 years without valve replacement. Major heart surgery is needed to replace the valve with a mechanical (eg, carbon fiber and metal) or tissue (eg, the aortic valve “borrowed” from a pig) valve.

But like I mentioned above, aortic stenosis can sometimes be encountered in a much younger patient….sometimes as young as in the 20’s. And this is often due to a congenital abnormality of the aortic valve in which there are only 2—and not the standard 3—leaflets. This occurs in 1-2% of the general population. For some reason, this arrangement predisposes the individual to earlier calcification and stenosis of the valve as well as leaking of the valve. This is relevant to the athlete because problems are likely to develop during the very active portion of a typical athlete’s active lifetime.

The second important consideration in patients with bicuspid aortic valve is that they are much more likely to develop enlargement (aneurysm) of the beginning portion of the aorta, as it leaves the heart. Over time, the aorta can enlarge from its typical diameter of less than 3 cm to 5 cm or more, the aorta and the aortic valve should be replaced….again, with major heart surgery

Professional triathlete, Torbjorn Sindballe, was recently in the news when he retired from competition because of bicuspid aortic valve and mild aortic enlargement.

Decisions about continued participation for patients with these conditions will need to be individualized, but should only be made after careful consideration of the risks involved. Athletes with mild to moderate aortic stenosis, and who don’t have symptoms, probably can participate fully in athletic activities. Those with severe aortic stenosis should refrain from strenuous activity as treatment plans are made with their physicians. Athletes with bicuspid aortic valve and enlargement of the aorta should refrain from strenuous activity.

Article from a Reader: Mediterranean Diet for Athletes

2009-10-26T11:23:00.000-07:00

Losing weight seems like such a simple thing, but in fact it is hard for many people. With well known diets on the market such as The South Beach Diet and Atkins' Program, many have jumped on the low carbohydrate bandwagon. But what about athletes that need protein and carbohydrates to sustain energy? These types of diets do not address their needs. While they both advocate adequate protein, the carbohydrate levels are too low for anyone in sports activities or bodybuilding.

Athletes use carbohydrates for energy just before an event or competition. Also they need adequate amounts of protein because it helps to repair damaged muscle. A diet for athletes must meet these requirements. One such diet is The Mediterranean Diet. This diet advocates the use of grains, dairy and fats such as olive oil. Olive oil is good for your heart and also lowers cholesterol; Italians eat olive oil on their bread instead of butter or margarine. People living in the Mediterranean have eaten this way all their lives and are very healthy.

The diet is named after the area where it originated and is associated with good health and a long life. The dietary lifestyle of Italy and Greece has shown consistent low mortality rates for the past 25 years. The basics of the diet include whole grains, fruits and vegetables, poultry, eggs, and fish, nuts and seeds, cheese and yogurt, olive oil and a limited amount of red meat.

The diet focuses on healthy fats, whole grains, fruits and vegetables and protein. Complex carbohydrates break down slower in the digestive system and keep energy levels sustained. This makes the diet perfect for runners and triathletes. And although athletes normally limit the consumption of alcohol, one glass of wine a day is allowed.

An example of the daily menu:

Breakfast: Coffee, Oatmeal and whole wheat toast

Lunch: Pasta e Fagioli (pasta with navy beans), salad and piece of fruit

Dinner: Fish with vegetables and fruit for dessert

Some of the benefits of the Mediterranean Diet:

Lowered incidences of heart disease and lowered cholesterol. Studies done in Europe have shown this type of diet to reduce metabolic syndrome which is a precursor to Type 2 Diabetes. Also lower obesity rates, heart disease, cancer and high blood pressure. It is believed that this type of diet also promotes longevity and increases life expectancy.

The Mediterranean Diet is healthy, well balanced and perfect for anyone who wants to lose weight. This diet is approved by doctors and The American Medical Association.

About the Author

Valery Fortie is the Awareness Coordinator of the Mediterraneanbook.com organization. She is also the editor of the blog behind it. She focus her efforts to provide scientifically driven news on healthy Mediterranean Diet eating and drinking to prevent high blood pressure. Mediterraneanbook.com is a non commercial website created to preserve the Italian healthy eating traditions. Founded in 2004 in Italy, Mediterraneanbook.com feels very strongly about having informed consumers on duty in all healthy eating fields.

Useful Website: Mediterranean Diet

2009-10-23T07:35:00.000-07:00

One of our readers wanted to share a useful website about the Mediterranean diet.

We know that our diet is particularly important to cardiovascular health and the Mediterranean-style diet has many admirable features. In fact, many of my cardiology colleagues now recommend a Mediterranean diet for their patients with heart disease.

Our reader has also offered to guest-author a piece with recommendations on how athletes can adopt this type of diet. I'm looking forward to sharing this information with you.

Useful Website: Science of Sport blog

2009-10-23T07:25:00.000-07:00

Gordo Byrn, at Endurance Corner, led me to the Science of Sport blog. This is a terrific website, full of useful and scientifically factual information about a variety of topics of interest to athletes.

There is some useful information and editorial comment about sudden death in athletes in their archive that will interest our readers here. And there's so much more....

I'll include a permanent link to this website at the right.

Interesting Facts: Causes of Death

2009-10-21T11:49:00.001-07:00

I came across an article yesterday in the Dallas examiner.com that tabulated the risk of dying to various causes. The source of the data is not clear, and I can only assume that they refer to Americans, but I believe that these numbers relfect the lifetime risk of dying:

1 in 5, Heart disease
1 in 7, Cancer
1 in 24, Stroke
1 in 84, Motor vehicle accident
1 in 119, Suicide
1 in 218, Falling
1 in 314, Firearm assault
1 in 526, Pedestrian accident
1 in 1,008, Drowning
1 in 1,020, Motorcycle accident
1 in 1,113, Fire or smoke
1 in 4,919, Bicycling accident
1 in 5,051, Air/space accident
1 in 5,134, Accidental firearm discharge
1 in 9,968, Accidental electrocution
1 in 10,048, Alcohol poisoning
1 in 13,729, Hot weather
1 in 56,789, Hornet, wasp, or bee sting
1 in 62,468, Legal execution
1 in 79,746, Lightning
1 in 117,127, Earthquake
1 in 144,156, Flood
1 in 340,733, Fireworks discharge

By comparison, the risk of dying in a marathon is approximately 1 in 75,000, or something equivalent to the likelihood of dying from lightning or legal execution.

Follow-Up: Detroit Marathon Deaths

2009-10-21T11:34:00.001-07:00

I continue to receive questions about the deaths of 3 runners during the half marathon in Detroit this past weekend. I understand from the popular press that additional tests are needed before the autopsy reports can be finalized. More on that when additional information is available.

These deaths have stimulated a lot of discussion, though. There was an interesting article in the New York Times yesterday, entitled "Are Marathons Safe?" Some food for thought. Marathons, like any endurance sporting event, place a heavy demand on the cardiovascular system, so it shouldn't be surprising that an occasional participant dies a sudden cardiac death. But it's important to keep things in perspective....the risk is real but very, very small for any individual participant.

These sudden deaths in sporting events should motivate us to be more vigilant about screening for cardiovascular disease in athletes and paying attention to potential warning signs that deserve investigation.

Carotid Artery Dissection

2009-10-19T12:20:00.000-07:00

I got an email from a reader in the U.K. the other day. He had seen that I planned to write soon about carotid artery dissection and wanted me to know that he had organized a group on Facebook related to this medical problem.

Over the weekend, I had a chance to read through the many posts from members of the Facebook group and I learned a lot. I'll continue my work on writing a piece for the blog....and post it soon.

In the meantime, I wanted to let readers know about this Facebook resource. The group is called, simply, Carotid Artery Dissection.

In the News: Deaths at Detroit Marathon

2009-10-19T12:14:00.000-07:00

Several people have asked me about the 3 deaths that occurred during the Detroit Marathon on Sunday. At this point, I don't know anything more than what's been reported in the popular press. This article from clickondetroit.com summarizes the events that led to the deaths of 3 runners, ages 26, 36, and 65, in the half marathon event.

Autopsies are being performed today and more information should be available shortly. I'll bet that cardiovascular causes are responsible and I'll report back when I know more.

Hypertension (High Blood Pressure)

2009-10-19T12:10:00.000-07:00

Last week, somebody stopped me to ask me a few questions about blood pressure….and high blood pressure, in particular. The gist of the questions was to learn how high the blood pressure could be before he should be concerned. So here’s a little information about blood pressure.

What is the blood pressure?

The normal blood pressure is 120/80. The numbers are measured in millimeters (mm) of mercury (Hg) and are expressed as a systolic pressure (top number) over a diastolic pressure (bottom number). And hypertension is the medical term we use for high blood pressure. We call it systolic hypertension if the systolic pressure is >140 mm Hg or diastolic hypertension if the diastolic pressure is >90 mm Hg.

In the outpatient setting, the blood pressure is usually measured in the arm using a blood pressure cuff. It’s important to remember that the blood pressure is not completely constant, but rather fluctuates during the day according to activity. Frequent measurement of the blood pressure will help to find the “typical” blood pressure for any individual.

The blood pressure typically rises with patient age. There is usually a continuous rise in systolic blood pressure throughout life. The diastolic pressure usually increases until the 50’s, then levels off, and potentially falls later in life.

How common is high blood pressure?

Hypertension is the most common medical problem in the United States. Defined as a blood pressure of 140/90 mm Hg or greater, and including individuals who take blood pressure medication, nearly 65 million Americans (about one third of the population) have hypertension. And another 25% of Americans have “pre-hypertension,” a systolic blood pressure of 120-139 mm Hg or a diastolic blood pressure of 80-89 mm Hg.

Why is high blood pressure bad?

It turns out that, independent of any other risk factors you might have, high blood pressure is associated with an increase in future heart attack (myocardial infarction [MI]), heart failure, stroke, and kidney disease. In fact, for each increase of 20 mm Hg in the systolic blood pressure or 10 mm Hg in the diastolic blood pressure, there is nearly a doubling of the risk of mortality for heart disease and stroke. It’s pretty sobering.

Treatment of high blood pressure

For individuals with no other medical problems (completely healthy otherwise), the goal of treatment is to lower the blood pressure to 140/90 mm Hg. For individuals with any adverse risk factors (diabetes, chronic kidney disease, coronary artery disease, carotid artery disease, peripheral arterial disease, aortic aneurysm, history of smoking, or elevated blood lipids), the goal of treatment is to lower the blood pressure to 130/80 mm Hg.

For all individuals with hypertension, one focus should be on lifestyle modifications that may foster a lower blood pressure. This would include a prudent diet with reduced saturated and total fat intake and reduced salt intake; physical exercise; weight reduction in patients who are obese or overweight; and moderation of alcohol intake. Vigorous attention to these measures may be sufficient in some individuals to lower the blood pressure to the target range.

Most individuals with hypertension will need medications to lower the blood pressure. And there are a great many medications available for this purpose. It’s impossible to generalize here about which particular medications will be most helpful in any individual patient. It’s important to work with your physician to find the best medicine (or combination of medicines) to treat your hypertension effectively. Athletes may want to avoid beta-blocker medications which blunt the heart rate response to exercise.

In the News: Heart Attack During Competition

2009-10-16T06:11:00.000-07:00

This article at abc.net describes how an athlete in his late 40's died of a heart attack during a canoe marathon event at the World Masters Games in Sydney earlier this week.

Coming up, we'll look at coronary artery disease, its risk factors (and ways to modify those risk factors), and its influence on athletes as they age. Stay tuned....

Follow-up: Heart Transplant Recipient at Kona Ironman

2009-10-13T14:03:00.000-07:00

I was pretty excited for Kyle Garlett, who was trying to become the first heart transplant recipient to complete the Hawaii Ironman race. And just 3 years after his transplant. Unfortunatey, things didn't work out....and Kyle wasn't able to complete the 2.4 mile swim before the cutoff.

I watched the online coverage of the race on Saturday at UniversalSports.com and saw that there were a couple swimmers who just barely missed the cutoff time. So close....

Kyle's follow-up story is detailed in this article at Silicon Valley MercuryNews.com.

Hypertrophic Cardiomyopathy (HCM)

2009-10-13T11:22:00.000-07:00

I received an email inquiry yesterday from a reader who was interested in hypertrophic cardiomyopathy (HCM), a newly-diagnosed condition which had sidelined him from the sport that he loves. I thought I’d share some information about HCM that I shared with him yesterday. This is an uncommon problem, but it is a potentially lethal problem for athletes in sports with high cardiovascular demands.

What is HCM?

We use the terms hypertrophic cardiomyopathy (HCM) when there is thickening (that we call hypertrophy) of the ventricular (lower heart chamber) walls, if there is no other explanation. This disorder has been known by several other names in recent years, including hypertrophic obstructive cardiomyopathy (HOCM) and idiopathic hypertrophic subaortic stenosis. There are several patterns, but in the most common situation the septum (that divides the left and right ventricles) enlarges to >1.3 cm, while the other ventricular walls remain <1.0>

In approximately 35% of cases of HCM, there is also obstruction to the flow of blood as it leaves the heart. This obstruction can be due to the thickening of the ventricular septum or to a condition known as systolic anterior motion of the mitral valve (SAM). With SAM, the mitral valve moves forward and gets in the way of blood that is heading toward the aortic valve to leave the heart.

Symptoms

Many individuals with HCM will have no symptoms at all. Some patients report instances of chest pain, with or without exertion, shortness of breath, palpitations, or syncope (blacking out), either during exertion or afterwards.

Role in Sudden Death

In the United States, HCM is probably the leading cause of death among athletes with sudden cardiac death. In most reports, HCM is found at autopsy in as many as 40% of young athletes with sudden death. Unfortunately, sudden death in individuals with HCM tends to occur in young people with no previous warning signs, who are engaged in moderate to strenuous physical activity.

Diagnosis

The diagnosis of HCM is established with an echocardiogram (an evaluation of the heart’s structure using ultrasound). The echocardiogram makes detailed pictures of the various heart walls and heart valves and the thickness of the various heart walls can be measured. The echocardiogram can also be used to estimate the degree of obstruction to blood flow exiting the heart.

Treatment

The treatment for HCM will depend on many variables that are specific to the individual patient. In general, treatment is designed to: 1) treat (or prevent) heart failure that may arise and 2) prevent sudden death. Potential treatments include medications, surgery (to remove some of the thickened heart wall or to replace the mitral valve), injection of alcohol into the heart wall (alcohol ablation) to cause it to shrink, insertion of a pacemaker, or insertion of a defibrillator (that delivers a shock to restart the heart in the event of sudden death).

Distinguishing from "Athlete’s Heart"

For athletes, there can sometimes be confusion about the diagnosis of HCM. This stems from the fact that well-trained athletes often have thickening of the ventricular walls that is simply a physiologic consequence of training. The distinction between HCM and athlete’s heart can be particularly problematic for individuals with ventricular wall thickness between 1.0 and 1.5 cm. Athletes in this situation would be well-served by consultation with a cardiologist with particular expertise in this area. Features that would favor athlete’s heart over HCM include: left ventricular cavity size >55 mm in diameter, and decrease in wall thickness with deconditioning. Features that would favor HCM include: family history of HCM, abnormal ECG, left ventricular cavity <45>

Recommendations for Athletes

Consensus panels have convened to make recommendations for athletes with HCM. Athletes with HCM who are younger than 30 years old should not participate in sports with high cardiovascular demands. Athletes with HCM who are older than 30 years old should not participate in such sports if they have any other worrisome features of the disease: ventricular arrhythmias, syncope (blacking out spells), moderate or worse obstruction to ventricular outflow (such as with systolic anterior motion of the mitral valve), intermittent atrial arrhythmias, or enlarged left atrium. Older athletes HCM who do not have these features should consult with their cardiologist about continued participation.

In the News: Ex-NFL players and heart disease

2009-10-09T13:50:00.000-07:00

Nice article at Science Daily last week, entitled "Despite Size, NFL Players Not More Likely to Develop Heart Disease Even After Retirement," commenting on a report in the September issue of American Journal of Cardiology.

Many football players, at all levels, have a body mass index (BMI) that puts them in the "overweight" or "obese" categories. Since we know that obesity is a strong risk factor for cardiovascular diseases, one might suspect that ex-football players would have a high rate of cardiovascular disease. Perhaps, surprisingly, this isn't so.

Flora ("Flo") Hyman, Volleyball Player, 1954-1986

2009-10-08T09:32:00.000-07:00

Flo Hyman was a professional volleyball player who grew up in Inglewood, California. She was a volleyball player for most of her life, playing at Morningside High School and later at the University of Houston. She left college before graduating to join the U.S. national volleyball team in 1977.

Flo spent almost 10 years playing volleyball at the highest level. The American team qualified for the 1980 Moscow Olympics, but the Games were boycotted by the American athletes. She would go on to win a silver medal in the 1984 Los Angeles Olympics. After those Olympic Games, Flo moved to Japan, where she played for the professional Daiei team.

Flo died on January 24, 1986 during a volleyball game. She was sitting on the bench, shortly after substituting out, and collapsed suddenly. At first her death was attributed to a heart attack, but an autopsy later showed that she died of aortic dissection that resulted from an undiagnosed condition known as Marfan syndrome.

Marfan syndrome is a rare genetic disorder that affects approximately 1 per 10,000 individuals. The disorder is inherited in autosomal dominant fashion, meaning that you can inherit the disorder from either parent. The defect is in the fibrillin-1 (FBN1) gene that is carried on chromosome 15. The disorder causes abnormalities in the connective tissues of the body, affecting the skeleton, the eyes, and, most importantly, the cardiovascular system. Famous people in history who are thought to have had Marfan syndrome include Julius Caesar, Abraham Lincoln, and Sergei Rachmaninoff, among others.

Individuals with Marfan syndrome have a characteristic appearance, with tall slender stature, long limbs, long fingers, abnormal eye lenses, and sometimes a funnel chest. Indeed, Flo Hyman was 6’ 5” tall when she died, but she had reached the height of 6’ by her 12th birthday. The diagnosis is usually established by these clinical features and a family history of the disease, but genetic testing is now available, if needed, to confirm the diagnosis. There is no cure for this disorder, per se, but with careful medical attention, serious (and potentially life-threatening) complications can be avoided.

For athletes, the problem lies in the cardiovascular features of the syndrome. A variety of problems are found in individuals with Marfan syndrome, including mitral valve prolapse (abnormal closing of the mitral valve), leaking heart valves (aortic valve, mitral valve, tricuspid valve), and arrhythmias. The most important cardiovascular complications with Marfan syndrome are the development of aortic aneurysm (enlargement of the aorta anywhere along its length) and dissection of the aorta (sudden tearing apart of the layers of the aorta, usually associated with high blood pressure). Aortic dissection that occurs suddenly is often fatal before proper medical attention can be obtained.

The two sports where Marfan syndrome is typically found are basketball and volleyball, just by the nature of the disorder being found in unusually tall individuals. But, of course, the syndrome could be present in an athlete competing in any sport. Athletes with the clinical features of Marfan syndrome should be screened for the disorder. Those who are found to have Marfan syndrome will need to work closely with their physician and/or cardiologist to determine whether continued participation is prudent. Affected athletes should have the blood pressure controlled carefully because we know that uncontrolled high blood pressure increases the risk for aortic dissection. These athletes should also be monitored closely for the development of problems with the heart valves and for the development of aortic aneurysm.

In the News: Heart transplant patient at Kona Ironman

2009-09-28T08:02:00.000-07:00

Nice article at cnnhealth.com about Kyle Garlett who will be competing at the Ironman World Championship in Kona in a couple weeks. In August, 2008, Dwight Kroening was the first heart transplant recipient to complete an Ironman race, at Ironman Canada.

Amazing what a new (healthy) heart can do!

Atrial Fibrillation in Athletes (In a Nutshell)

2009-09-25T17:29:00.001-07:00

My friends at Endurance Corner recently circulated an abstract about atrial arrhythmias in endurance athletes and I thought this would be a great topic for the blog. At the outset, let me say that entire books have been written on the topic of atrial arrhythmias, so anything here will necessarily be the story “in a nutshell.”

What is Atrial Fibrillation?

In the normal situation, the electrical activity of the heart is highly organized, starting as a self-initiating impulse in the sinus node located in the upper chamber on the right side of the heart (right atrium) and proceeding through the right and left atrium, then down into the lower chambers of the heart, the ventricles. In medical terms, the normal situation is a called a sinus rhythm. And when the heart rate is between 60 and 100 beats per minute, we call this a “normal sinus rhythm”. Any time the heart’s electrical activity is NOT a normal sinus rhythm, the situation is called an arrhythmia….and there are many different types. I realize that many athletes have a sinus rhythm at less than 60 beats per minute at rest—and ordinarily we’d call this a “sinus bradycardia”—but this is quite normal for the well trained athlete.

Today, we’re talking about atrial fibrillation (AF), the most common sustained arrhythmia. In this situation, the electrical activity in the upper chambers of the heart is highly disorganized. You might picture many circular electrical circuits all firing in disarray. The result is that the atria, the upper chambers of the heart, do not contract properly and electrical impulses reach the ventricles, the lower chambers of the heart, in an irregular sequence and often at a fast rate. The result is an irregular pulse (when you feel the pulse at the wrist, for example), a reduction in the cardiac output (the amount of blood the heart pumps each minute), and stagnation of blood within the atria. AF may be constant (or persistent or chronic) or intermittent (paroxysmal).

Thinking for a moment about the general population, the chance of having AF increases with age, The overall incidence is less than 0.5%, but that rate increases to more than 8% at age 80. This arrhythmia commonly accompanies other forms of heart disease such as mitral valve prolapse, rheumatic heart disease, or hyperthyroidism, but it may also occur alone. When it occurs alone, in the absence of other heart disease, we call it “lone atrial fibrillation.” In the United States, it is estimated than more than 2 million individuals are affected. And importantly, AF is associated with a variety of poor outcomes over the long-term, including stroke, heart failure, and even death. In fact, the mortality rate for individuals with AF is nearly twice that for individuals without AF.

AF can produce a variety of symptoms….and sometimes, no symptoms at all. The symptoms are usually due to a fast heart rate and include: palpitations, chest discomfort, shortness of breath, sweating (diaphoresis), and even syncope (blacking out). Palpitations are probably the most common symptom in athletes and, in fact, recent studies have shown that as many as 70% of athletes in some sports will report having palpitations during exercise. Most palpitations are benign, are not associated with any underlying heart disease, and require no treatment. But if palpitations are bothersome, the problem should be investigated.

Atrial Fibrillation in Athletes

Back to athletes…. What’s interesting is that athletes are much more likely than non-athletes to be bothered by AF. Not only is AF the most commonly encountered arrhythmia in athletes but also a variety of cohort studies have shown that the prevalence of AF in athletes is probably 2 to 3 times that of the general population. The reasons are not entirely clear, but there are several likely explanations. First, it is likely that the cardiovascular stresses placed on the athlete’s heart over the long term result in structural changes to the muscle tissue of the atria that foster irregular electrical activity. And it’s probably the case that not all sports are created equal in this regard (eg, the changes resulting from a career of golf might be different from those resulting from a career as a marathoner). Second, there is increased firing of various autonomic nerves that supply the heart might promote a disruption in the normal electrical activity. And lastly, low level chronic inflammation that accompanies exercise has been proposed as a possible explanation.

In athletes, intermittent AF is much more common than persistent AF, but either form can impair the athlete’s performance. Af can limit peak performance and can also become bothersome to the point that the amount of training which is possible is reduced.

Diagnosis of Atrial Fibrillation

How do we make the diagnosis of AF? Most patients will report 1 or more of the symptoms listed above and their physician will do an electrocardiogram (ECG). The ECG will clearly show the AF if the arrhythmia is constant, but may be completely normal if the AF is intermittent. A Holter monitor (a tape recorder of sort, with chest electrodes) can be worn for 1-3 days to “capture” any intermittent AF on tape. The Holter monitor can also be worn during treadmill or other monitored exercise to help “capture” the arrhythmia on tape.

Treatment of Atrial Fibrillation

Medical treatment. Medical treatment is focused on 2 alternative approaches: 1) rate control, where medicines are prescribed that keep the heart rate relatively low in spite of having the arrhythmia and 2) rhythm control, where medicines are prescribed to try to convert and keep the electrical activity in a sinus rhythm rather than AF. The typical rate control medications include: beta-blockers (propranolol, atenolol) and calcium channel blockers (diltiazem, Verapamil). The typical rhythm control medications include Amiodarone and Sotalol, among others. Unfortunately, most long-term studies (primarily in non-athletes) show that all of these medications are often ineffective (<50%).>

A second medical consideration is blood thinning, or anticoagulation, to help prevent small blood clots from forming in the atria during AF and breaking loose and causing stroke. There are guidelines published by the American Heart Association and American College of Cardiology (ACC) that address this problem. For athletes with no other form of heart disease other than AF, a daily aspirin is probably prudent. For those with other forms of heart disease in addition to AF, a stronger anticoagulant such as Warfarin (Coumadin) may be recommended to reduce the long-term risk of stroke. Unfortunately for the athlete, blood thinning with Coumadin also carries a risk of severe bleeding if bodily injury occurs during sports activities.

Ablation treatment. Another option for individuals affected by AF is ablation, performed either as a catheter-based procedure or as a surgical procedure. In the catheter-based procedure, catheters are threaded up to the heart, often starting in the arteries or veins of the groin, and electrical energy is used to ablate (think “kill”) the tissue in the heart that is responsible for starting or propagating the abnormal electrical activity of AF. In the surgical version, a series of small port incisions are made in the chest wall on both sides, and using video assistance, tiny surgical surgical instruments are inserted into the chest to ablate the heart tissue, again using electrical energy. Both of these procedures can be very straightforward for patients with intermittent AF and can be much more difficult for patients with persistent AF. Regardless, the risks associated with these procedures are relatively small, and I would encourage athletes bothered by AF to give strong consideration to these options.

Guidelines for Participation in Sports

Athletes with AF whose heart rate is controlled (no higher than the typical sinus heart rate associated with exercise) can participate fully. Those athletes who require anticoagulation with Coumadin should avoid sports in which the risk of bodily injury is high (because of the higher risk of internal bleeding with injury).

In the News

2009-09-23T08:35:00.000-07:00

I'll keep my eyes open for interesting articles in the popular press related to heart disease and athletes and post links here.

A recent article in the Health Report column at US News & World Report online talks about cardiovascular screening in young athletes. Good reading. The article points to the increasing recognition that careful cardiovascular screening is important for school-aged athletes.

The Athlete's Cardiac Paradox

2009-09-14T20:30:00.000-07:00

With a nearly unquenchable thirst for healthier living, the ranks of athletes at all levels have grown over the past 20 years. More than 7 million high school athletes, nearly 400,000 college athletes, and countless millions of adult Americans now exercise routinely or take part actively in competitive athletics. The heart-healthy benefits of regular exercise have been widely documented, but we also know that strenuous exercise increases the risk of sudden death due to a variety of cardiac conditions, either known or unknown to the athlete. This is what I’ve been calling the athlete’s cardiac paradox.

There is ample evidence that regular exercise produces a variety of health benefits. As a result, physical activity is strongly recommended by educators, parents, and the medical community. We know, particularly in adults, that regular exercise can: 1) help to maintain a healthy weight; 2) reduce the incidence of type 2 diabetes; 3) have a beneficial effect on the blood pressure; 4) delay or limit the progression of typical coronary artery disease (“hardening of the arteries”); and 5) reduce the chance of having a cardiovascular event such as acute myocardial infarction (AMI), or “heart attack.” And beyond the cardiovascular benefits, there are social and psychological benefits for most individuals who make exercise a part of their daily or weekly routine.

But despite the many clear advantages of exercise, we’ve all heard reports of athletes who have died suddenly, often during exercise or competition. When famous athletes are involved, these stories often garner national news attention. But the problem affects local athletes just the same. For young individuals, the risk of death among athletes may be as much as 2.5 times the risk for non-athletes. For seemingly healthy adults, the reported risk ranges anywhere from 5 to 50 times. Thankfully, the absolute numbers of such deaths is relatively small, though. In the United States, the risk for young athletes is probably in the range of 1 sudden death per 100,000 athletes per year. There have been various estimates for the risk of exercise-related sudden death in adults, with a range of 1 per 20,000 to 82,000 individuals per year. But for adults, this is on top of an additional risk of exercise-related acute myocardial infarction (AMI), or “heart attack.”

For our purposes as we go forward, we should probably divide the athletic population into those under 30 years of age and those older than 30 years of age. This is obviously just an arbitrary cut-off, but it turns out that the cardiac conditions responsible for sudden death are very different for these two groups. For the younger group, hereditary or congenital conditions such as hypertrophic cardiomyopathy (HOCM), coronary artery anomalies, aortic stenosis, aortic dissection (especially with Marfan’s syndrome), arrhythmogenic right ventricular cardiomyopathy, and myocarditis predominate. For the older age group, typical coronary artery disease is the most common cause of sudden death.

As athletes, what should we do?

1. Be aware of the problem. It’s easy for the young athlete to believe he or she is invincible. The young athlete is often the picture of health. But this may not necessarily be true.

2. Take charge of your own (or your child’s) heart health. Nobody will do this for you. It’s important for athletes of all ages to establish a good relationship with a physician—and particularly one who is knowledgeable about the issues of heart disease in athletes. After they leave school, most “healthy” men don’t continue to see a physician. You and your physician should work together to plan how to best screen for any possible cardiovascular disease that you might have. And assuming it’s safe to proceed with your exercise program or training routine, you should work together when any issues arise. Treat symptoms such as chest pain, palpitations, unusual shortness of breath, or light-headedness (or blacking out) seriously. Report these to your physician and work exhaustively to find a cause.

3. Prepare for emergencies. This is particularly true if you’re involved in the leadership of organized exercise programs, training events, or competitions. Be ready for medical emergencies of all sorts, including those arising from cardiovascular problems, and particularly sudden death caused by arrhythmias. It will be helpful to all of us in the long term if cardiovascular events be reported and disseminated to the athletic and medical community. It’s the only way that we can learn.

As physicians, what can we do to help?

1. Become knowledgeable about the problem. I worry that too few primary care physicians are truly knowledgeable about the many issues related to cardiovascular disease in athletes. And I know that cardiologists with a particular interest in this area are few and far between. We should be ready to refer our patients to these specialists, though, when issues arise that we cannot resolve for the athlete.

2. Recommend appropriate exercise programs. There is sufficient information about many cardiac conditions that we can make sound recommendations about continued participation in sports activities for those affected individuals. For some athletes, this will mean a change in the type or intensity of exercise that is safe.

3. Exclude individuals from athletic activities if their cardiac conditions place them at very high risk.

These are some of the issues that we’ll explore in the weeks and months ahead. My friends at Endurance Corner sent me an abstract about atrial arrhythmias in endurance athletes. This is an interesting and common problem and I’ll be back next time to share some info.

Thanks for stopping by. I hope that you’ll stop back often and I hope that you’ll offer your comments, questions, and suggestions. I’m happy to talk about questions that might be on your mind. And I’ll bet that we have a great deal to learn from each other, too.

Ryan Shay, Marathoner, 1979-2007

2009-09-05T14:54:00.000-07:00

There have been a number of athletes with heart disease--in a variety of sports--who've captured the nation's attention because of sudden, unexpected death in recent years. Often these deaths have occured during training or competition. From time to time, I'll take a look at one of these athletes and describe their heart problems. There's probably something to learn in these examples about living (and exercising or training) with heart disease or preventing sudden cardiac death.

I was having dinner with some friends last weekend and the group included several runners and a couple doctors. We got to talking about heart disease in athletes and somebody asked me if I knew why Ryan Shay died.

To set the stage, Ryan Shay was a runner for most of his life. He grew up in Michigan where he was a multi-year high school state champion in the 1600m and 3200m events. He went on to college at Notre Dame, where he competed in both cross country and track. He was the NCAA champion at 10,000m in 2001 and was a 9-time All American. After college, he would go on to be the USATF marathon champion in 2003 and the USATF half marathon champion in 2003 and 2004. He finished a disappointing 23rd at the 2004 Olympic Trials, but had high hopes for the 2008 Trials.

Ryan Shay died in New York City on November 3, 2007, collapsing suddenly in Central Park, at mile 5.5 of the 2008 U.S. Olympic Marathon Trials. He received medical attention immediately, was taken to Lenox Hill Hospital, and was pronounced dead. An autopsy report was released several months later, describing the cause of death as "cardiac arrhythmia due to cardiac hypertrophy with patchy fibrosis of uncertain etiology....natural causes."

Interestingly, Ryan Shay was known to have heart disease since he was a teenager. After an automobile accident, he had a chest x-ray which showed that, compared to an x-ray done 3 years earlier when he had pneumonia, showed his heart had enlarged appreciably. I'm not certain if any further diagnostic testing was undertaken, but the problem didn't seem to hamper Ryan.

Of course, there's probably no way to be absolutely certain what caused Ryan Shay's death. But I think the information that's available suggests a likely scenario. When the pathologist describes "patchy fibrosis," she is referring to scar tissue that has developed in the heart....due to injury of some sort, just like scar tissue develops elsewhere in the body. Fibrosis in the heart in a young person is very unusual, though. In an older individual, fibrosis can develop commonly after injury like heart attack. But Ryan had no evidence of the coronary artery disease that causes heart attacks. Much more likely, Ryan had an episode of myocarditis, a viral infection of the heart that occured during childhood. In the aftermath of that infection, his heart enlarged and there was scarring in the heart muscle.

Ryan Shay's heart obviously was strong in terms of its pumping function. No elite runner could achieve Ryan's accomplishments without a "strong" heart. Unfortunately, the fibrosis in his heart was a "set-up" for the event that occured on the day of his death. The heart's ordinarily highly organized electrical activity (that causes the various chambers to contract in the correct sequence) can become irregular because of areas of fibrosis in the heart walls. This can result in suddenly disorganized electrical activity (that we call an arrhythmia--likely ventricular fibrillation) that leaves the heart unable to contract and pump blood effectively. The blood pressure falls to zero and unless the electrical activity is returned to normal within minutes (using a defibrillator), the individual dies.

As we explore the spectrum of heart disease in athletes in the weeks and months ahead, we'll see that the development of an arrhythmia is often the common final pathway that leads to sudden death in athletes. But there are many disorders besides myocarditis that can lead to this problem.

Syncope--Part 2

2009-09-04T12:15:00.001-07:00

Last week we talked about the problem of syncope and described the various causes. This week we’ll talk about the medical evaluation and treatment for the athlete with syncope. As I explained last week, syncope can sometimes be explained simply by benign problems such as dehydration, but the majority of individuals should be evaluated carefully for an explanation. This is particularly true for the athlete because of the demands placed upon his cardiovascular system and the potential risk of sudden death from unrecognized underlying heart disease.

MEDICAL EVALUATION

In general, the medical evaluation of patients with syncope should seek to determine a specific cause, with a special emphasis on distinguishing heart-related (cardiac) from non-cardiac causes. And, as for the evaluation of most medical problems, your physician will want to gather information from a careful medical history, including the syncopal event itself, a physical examination, and then one or more diagnostic tests. Because syncope is a common problem in the general population, most primary care physicians are knowledgeable about the evaluation of patients with syncope, but sometimes referral to a cardiologist, neurologist, or other medical specialist may be necessary.

Medical History

Much information can be gathered from a careful medical history. Your physician will be particularly interested in the events leading up to, and immediately after, your episode of syncope. In some cases, information provided by bystanders may be very important. This is particularly true if you have experienced a loss of memory (amnesia) for the events immediately preceding the syncopal event. Syncope should be distinguished from near-syncope, or “almost blacking out.” For our purposes here, we’re considering only syncope, characterized by a true loss of consciousness. Your physician will also want to know about any previous episodes of syncope, about any medications you may be taking (especially beta-blockers or inhaled bronchodilators for asthma), and about any personal or family history of heart disease.

Athletes with neurocardiogenic syncope typically report that their syncope occurred in the standing position, often after exercise, and often in the setting of some degree of dehydration. The syncope is usually preceded by feelings of light-headedness, a warm feeling, or nausea. Athletes may have experienced episodes of near-syncope previously and learned that prolonged standing after exercise should be avoided.

Athletes with situational syncope often relate a history of a causative symptom that reproducibly produces syncope.

Athletes with orthostatic syncope typically report the development of syncope when they change from the sitting to standing position. Upon reflection, they may admit to some degree of dehydration.

Athletes with neurologic syncope often report neurologic symptoms (eg, vertigo, visual changes, or muscle movement clumsiness) that precede their syncopal event. These athletes might be well served by referral to a neurologist for further evaluation and treatment.

More worrisome is syncope that occurs during exertion or in the sitting or lying positions. Syncope that is preceded by palpitations or chest pain or discomfort is also worrisome. All of these features suggest a cardiac cause and merit a more thorough search for a cardiac cause.

Physical Examination

In many cases, the physical examination will be unremarkable and offer no clues to the cause of syncope. Nonetheless, in some small number of cases, though, there will be specific clues from the physical examination that point to an underlying condition that might be the cause of syncope.

Patients should have their vital signs (heart rate and blood pressure) measured in the supine, sitting, and standing positions. Findings here may point to orthostatic hypotension as a cause of syncope.

The body habitus (height and shape) may suggest Marfan’s syndrome and this can be evaluated further with genetic testing. Your physician may hear bruits (or turbulent blood flow) in the carotid arteries, suggesting underlying vascular disease. The heart sounds may be abnormal, including the presence of an S3 or S4 gallup, but these findings are common in athletes even without a history of syncope. A careful examination should be made for evidence of heart valve disease because specific murmurs may suggest a cause of syncope and prompt further testing.

Diagnostic Tests

Athletes with syncope should have a complete medical history and physical examination and then have an electrocardiogram (ECG) and echocardiogram to complete the initial evaluation. The resting ECG and echocardiogram will identify or exclude many of the potential cardiac causes of syncope. The information gathered from these tests will then be used to determine if any additional diagnostic testing is needed.

Electrocardiogram (ECG). The ECG is usually done in the physician’s office and the results are immediately available. Electrodes are attached to the chest, arms, and legs and are used to make recordings of the heart’s electrical activity measured at the skin surface. In athletes with syncope, the ECG may be abnormal in 50% of cases, but will point to a specific cause of syncope in only a very small number of cases. Abnormalities that can be identified on the ECG that may be responsible for syncope include: long QT interval, pre-excitation or Wolff-Parkinson-White syndrome, pauses in the electrical activity, or heart block. It’s not so important that the athlete understand each of these possibilities; instead, any of these findings will prompt your physician to do additional diagnostic testing or to provide a specific treatment.

Echocardiogram. The echocardiogram is usually ordered by the physician and done in a cardiologist’s office or at the hospital. With the use of ultrasound, images are made of the heart that show the anatomy (structure) of the heart in great detail. The size of the heart chambers and heart walls can be made, the structure and function of the heart valves (aortic valve, mitral valve, pulmonary valve, tricuspid valve) can be determined, and estimates of the pressures in each of the heart chambers can be made. In the athlete without a history or physical findings that suggest cardiac disease, the chances of finding an abnormality with echocardiography are low, but not zero. Cardiac conditions that may cause syncope and which can be diagnosed with echocardiography include: aortic stenosis (narrowing of the aortic valve), benign tumors of the heart (eg, myxomas that obstruct blood flow in the heart), or hypertrophic obstructive cardiomyopathy (HOCM).

Holter monitoring. If the athlete reports an abnormal history of palpitations or if palpitations have immediately preceded the syncopal event—and if the ECG and echocardiogram do not suggest other cardiac diseases—holter monitoring may be useful to diagnose arrhtyhmias (abnormal heart rhythms) that may be responsible for syncope. With this test, the patient wears a tape recorder and several electrodes for a period of 24-72 hours and a recording is made of the heart’s electrical activity. The patient can often press a button to indicate symptoms such as palpitations that may later be correlated to the heart’s electrical activity at that moment. The Holter monitor may uncover atrial arrhythmias (often responsible for near-syncope) or ventricular arrhythmias (often responsible for syncope). This test may also show periods of heart block or pauses in the electrical activity that are not evident on the resting ECG.

Tilt-testing. For the athlete with syncope, and for whom the ECG and echocardiogram do not suggest a cardiac cause, tilt testing is the next appropriate diagnostic test. This test is used to establish the diagnosis of neurocardiogenic syncope and is done in a cardiologist’s office or at the hospital. The patient is strapped to a tilt table and measurements are made of the vital signs in various positions. Intravenous medications may be given to exaggerate the effects of the test and help the physician establish a diagnosis.

Other cardiac tests. A variety of additional diagnostic tests are available for patients in whom a cause for syncope cannot be determined on the basis of history, physical examination, ECG, echocardiogram, Holter monitoring, and tilt-table testing alone. Additional underlying cardiac diseases (that may be responsible for syncope) can be identified or excluded using: stress testing, cardiac catheterization, more extensive electrophysiologic testing, or the use of an implantable loop recorder (to make more extensive recordings of the heart’s electrical activity). If an athlete’s cause of syncope remains uncertain after the more basic tests—and particularly if syncope occurs with exertion—he should be referred to a cardiologist for evaluation and, possibly, one or more of these additional diagnostic tests.

TREATMENT

The treatment for athletes with syncope will be individualized and targeted at the underlying cause. The goal of treatment will be to prevent (or reduce the frequency of) future episodes. For athletes in whom a cardiac cause is determined, there will be specific treatments for any of the myriad of responsible cardiac causes. We’ll discuss these treatments at another time and consider whether continued participation in athletic activity is prudent.

For athletes with situational syncope, the inciting cause should be avoided. For athletes with orthostatic syncope, dehydration should be avoided and medicines such as beta-blockers should be discontinued. For patients with neurologic syncope, further diagnostic testing under the direction of a neurologist may be needed.

Most commonly, however, athletes will be found to have neurocardiogenic syncope and there is a variety of treatment options.

Avoidance. The most important “treatment” will be to avoid situations that predispose the athlete to developing syncope. And the most common situation to avoid is prolonged standing after exercise—particularly strenuous exercise. It is important for the athlete to recognize their own specific premonitory symptoms (eg, light-headedness, nausea) and remember to sit down or lie down to prevent a syncopal episode.

Blood volume. Anything that produces a relative or absolute decrease in the circulating blood volume (eg, dehydration, certain medications) should be avoided. Compression stockings in the post-exercise period may be helpful in this regard.

Drugs. Many different medications have been used to treat patients with neurocardiogenic syncope, including beta-blockers (eg, propranolol, atenolol), alpha-agonists (eg, midodrine), and calcium channel blockers (eg, disopyramide). Unfortunately, long-term studies have often failed to show a convincing benefit. Importantly, beta-blockers may be poor choice in athletes because these medications limit the heart rate.

NEXT WEEK

Next week, I’ll be back to talk about what I’ve called the athlete’s cardiac paradox.

Syncope--Part 1

2009-08-21T12:26:00.000-07:00

Some of you will know about professional triathlete Joanna Zeiger’s recent troubles with syncope. Her trials and tribulations with race-related dizziness are summarized in a nice article at slowtwitch.com, “Zeiger sidelined by dizziness.” Her story is typical. This week and next week, we’ll talk about the causes, medical evaluation, and treatment options for syncope.

Syncope is the medical term used to describe a brief period of loss of consciousness (either partial or complete) that is due to insufficient blood flow to the brain. This process is temporary and is followed by spontaneous recovery. Patients often use different terms such as “dizziness”, “light-headedness”, “blacking out”, “passing out”, or “falling out” to describe this problem. This is a common medical condition that affects approximately 3% of the population at some point during life. It is increasingly common as we age, affecting 6% of individuals over the age of 75. It’s not surprising, then, that this is a fairly common problem among athletes.

Syncope may occur without warning or may be preceded by warning signs that are called premonitory symptoms. Typical premonitory symptoms might include palpitations, light-headedness, grogginess, feeling warm, or experiencing nausea.

TYPES OF SYNCOPE

There are many types or causes of syncope and it can be useful to categorize the types as: 1) cardiac (heart-related), 2) non-cardiac, or 3) unknown. This framework helps the physician sort out an individual’s cause among the many possibilities and then provide any needed treatment.

Cardiac syncope

A variety of cardiac disorders can produce syncope, but cardiac causes account for the explanation in only 10% of cases. As patients age, it is more likely that a cardiac cause is responsible for their syncope. Some of the cardiac causes are potentially life-threatening, but most are less serious; all can be treated.

Life-threatening cardiac causes. Acute myocardial infarction (“heart attack”) or aortic dissection (tearing apart of the layers of the aorta) can produce syncope or other changes in the level of consciousness. Both of these conditions are usually accompanied by chest or back pain and can also be associated with shortness of breath. In these situations, syncope is the result of decreased blood pressure and/or decreased blood flow to the brain. Both of these conditions can result in sudden death and affected individuals require urgent medical attention.

Arrhythmias. The most common cardiac cause of syncope, though, is an abnormal heartbeat, or arrhythmia—either atrial (from the upper heart chamber) or ventricular (from the pumping chamber of the heart). Syncope can be the result of an abnormally fast (tachy-) or slow (brady-) arrhythmia. Bradyarrhythmias are usually found in patients with known, pre-existing heart disease, but they sometimes occur because of unwanted side effects of medicines (eg, beta-blockers for high blood pressure). It’s important to remember that the well-trained athlete typically has a baseline slow heart rate and this can sometimes confuse the picture. Syncope is more common with atrial or ventricular tachyarrhythmias, though. The atrial tachyarrhythmias include atrial fibrillation (A-fib), atrial flutter (A-flutter), and supraventricular tachycardia (SVT). These arrhythmias may be accompanied by chest discomfort, palpitations, or shortness of breath. With persistent arrhythmias, syncope often occurs when moving from the sitting to standing position (postural) due to decreased blood pressure. Ventricular tachyarrhythmias include ventricular fibrillation (V-fib) and ventricular tachycardia (V-tach). These arrhythmias are usually associated with known, pre-existing heart disease. Syncope due to ventricular tachyarrhythmias is not usually related to posture.

Cardiac bloodflow obstruction. A third set of cardiac causes of syncope are due to obstruction to blood flow in the heart. This can be due to narrowing (stenosis) of the aortic, mitral, or pulmonary valves, hypertrophic obstructive cardiomyopathy (HOCM, one of the most common causes of sudden death in athletes), or to tumors of the heart. With these conditions, syncope is often sudden, without any preceding symptoms.

Low cardiac output. The last set of cardiac causes are those due to decreased pumping function, or cardiac output, from the heart. Long-standing congestive heart failure (CHF) or leaking (regurgitant) heart valves may lead to a low blood pressure that limits blood flow to the brain.

Non-cardiac syncope

Neurocardiogenic syncope. The most common type of syncope is termed neurocardiogenic, or vasovagal syncope. The term vasovagal conveys the association of “vaso,” for vasodilation of arterial system (leading to a decrease in blood pressure) and “vagal,” for the accompanying slow heart rate (sometimes produced by decreased activity in the vagal nerves). This type of syncope usually occurs in the standing position and is usually preceded by symptoms such as light-headedness, nausea, or sweating.

Situational syncope. A variety of precipitating factors, such as emotional stress, anxiety, pain, cough, urination, or defecation can lead to syncope. In this situation, the resulting syncope is thought to be due to a reflex, sudden decrease in heart rate that produces a transient reduction in blood flow to the brain.

Orthostatic syncope. Syncope can be caused by a sudden drop in the blood pressure as we rise from a sitting to standing position. The medical terms for this situation are orthostasis, or orthostatic hypotension (reduced blood pressure). Ordinarily, the body adjusts to this change in position by increasing the heart rate and increasing motor tone in the blood vessels to keep the blood pressure constant. When these mechanisms fail, the sudden (relative) drop in heart rate and blood pressure may produce syncope. This problem can be made worse by dehydration or medications that reduce the circulating blood volume or by medications that limit the blood pressure response (eg, beta-blockers).

Neurologic syncope. One last, unusual category of causes is termed neurologic. In this situation, the syncope is caused by a sudden decrease in blood flow to the brain in conditions such as stroke, transient ischemic attack (TIA, or “near-stroke”), or seizures. In one variant, syncope is due to a sudden decrease in blood flow to the posterior portion of the brain called the cerebellum. This is often due to pre-existing vascular disease in the vertebral arteries that supply this portion of the brain. Patients with neurologic syncope often experience other neurologic symptoms such as vertigo, visual changes, or muscle movement clumsiness immediately before the syncopal event.

MEDICAL EVALUATION

Syncope can sometimes easily be explained by benign problems such as dehydration, but the majority of individuals with syncope should be evaluated carefully for an explanation. Because of the demands on the athlete’s cardiovascular system during exercise, it is particularly important for the athlete with syncope to be evaluated completely.

NEXT WEEK

Next week, we’ll talk about the medical evaluation of patients with syncope and discuss the various treatment options.