cycling

Thoughts on the Recent VeloNews Article

September 1, 2015 By Larry Creswell, MD 3 Comments

I enjoyed reading a recent article in VeloNews by Chris Case, entitled “Cycling to Extremes: Are endurance athletes hurting their hearts by repeatedly pushing beyond what is normal?” The article is good reading.

First, I give a lot of credit to Chris Case and the editors at VeloNews. It’s great that a publication with such a broad audience would devote time and space to the issue of heart health and endurance sport. In recent months, they’ve also brought attention to the heart problems of pro cyclists, Robert Gesink, Olivier Kaisen, and Eddy Merckx. I wish that other writers and publications would do the same.

I also thank Lennard Zinn and Mike Endicott for sharing their personal stories with their heart problems. It would be very easy to keep quiet. I very much enjoy reading personal accounts such as these. Their stories are real and also familiar. This is how we learn.

Since the article was published, I’ve gotten a bunch of inquiries asking my opinion about the article in general or about specific information that was presented. Let me share a few thoughts that may be helpful to readers here at the blog….

Don’t be scared (too much)! For most people, cycling is a healthy pursuit. In general, exercise is healthy and provides a myriad of benefits. So don’t stop cycling! It’s important to keep in mind that the stories of Zinn and Endicott are not the norm, even among veteran endurance athletes. Zinn’s multifocal atrial tachycardia (MAT) is one of the least common atrial arrhythmias and Endicott’s sudden cardiac death is rare. As you absorb their stories, focus not on the particular arrhythmias but rather on the possibility that an arrhythmia–any arrhythmia–can cause significant problems or be an indication that things are amiss with the heart. In that sense, their stories should cause you to put on your thinking cap.

My favorite quote from the article? “But fit for racing doesn’t necessarily equal healthy.” Readers here at the blog will know that I’ve said this repeatedly. It’s easy for seemingly healthy endurance athletes, particularly men, to believe that fitness is the same thing as healthiness. This isn’t necessarily true. To dispel the myth, I’ve shared the stories of many elite endurance athletes who’ve struggled with heart problems of various sorts. We can add Zinn and Endicott to these lists. Heart problems are common….and athletes aren’t exempt. This is the most important take-home message from the article.

Arrhythmias are common–in athletes and non-athletes, alike. All athletes experience arrhythmias. Infrequent premature beats, originating in either the atrium (premature atrial contractions, or PAC’s) or in the ventricles (premature ventricular contractions, or PVC’s) most likely have no consequence. Sustained arrhythmias, on the other hand, deserve attention and evaluation. There are far too many varieties of arrhythmias to consider here, other than to mention some of their names: SVT, or supraventricular tachycardia; WPW, or Wolff-Parkinson-White syndrome; atrioventricular (AV) nodal re-entry tachycardia; atrial or ventricular bigeminy; sick sinus syndrome; sinus bradycardia; atrial fibrillation (AF); atrial tachycardia; MAT; ventricular tachycardia (VT); and ventricular fibrillation (VF).

The last part of the VeloNews article alludes to AF. Other than sinus bradycardia (simply a heart rate slower than 60 beats per minute, which may be very healthy in athletes) or innocuous premature beats, AF is probably the most common arrhythmia in athletes. We know from longitudinal studies that the lifetime risk of having AF is approximately 25% in the general population. The question of whether athletes–and endurance athletes, specifically–are more prone to AF is a current controversy, with important implications for long-term endurance athletes. I’ll try to finish up a separate blog post that summarizes the accumulated evidence on this issue. For men, there may be an association with long-term exercise and the prevalence of AF, but there is certainly no consensus among experts. For women, the evidence does not suggest an association between long-term exercise and AF.

Pay attention to warning signs. I particularly like the last section of the article, written by Dr. John Mandrola. He’s a cardiologist who specializes in arrhythmias and who is also a (former?) triathlete and current avid cyclist. He provides good advice in the Q&A. I like to talk about 5 important warning signs of possible heart disease: chest pain or discomfort, especially during exercise; unexplained shortness of breath; light-headedness or blacking out (syncope), especially during exercise; unexplained fatigue; and palpitations–the sense of a rapid or irregular heartbeat. Any of these warning signs may be due to an arrhythmia. All deserve investigation. Dr. John makes the apt point that, very often, heart rhythm problems start off small and get worse with time. Not surprisingly, it’s best to get things sorted out earlier rather than later.

Less may be more. Lastly, I would encourage athletes with identified arrhythmias to be open to the idea that less exercise may be helpful. In fact, this may be the most appropriate prescription. For the long-term endurance athlete, this can be difficult to accept. In this regard, the stories of Zinn and Endicott are particularly poignant.

2. Atrial Fibrillation in Athletes (in a Nutshell)

3. Too Much Exercise, Revisited

4. Don’t Stop Running Yet!

Do Elite Athletes Live Longer?

November 12, 2013 By Larry Creswell, MD 3 Comments

Do elite athletes live longer?

Most of us aren’t elite athletes, of course. But most any athlete is interested in the answer to the question.

In the past year, there have been two scientific reports on this issue–one examining longevity of Olympic medalists in the modern area and another examining longevity of riders in the Tour de France.

The Olympians

The first study was undertaken by Dr. David Studdert and colleagues from the Melbourne (Australia) School of Population Health. They asked the question: Do Olympic medalists live longer than the general population? These investigators estimated that since the birth of the modern Olympic movement in 1896, some 25,000 individuals from 136 different countries had won medals. Their report, though, focused on 15,174 medalists at the Games from 1896-2010 who hailed from a subset of 9 country groups that accounted for the majority of medals won (United States, Germany, the Nordic countries as a group, Russia, the United Kingdom, Frane, Italy, Canada, Australia, and New Zealand). For the purpose of comparison, each medalist was paired with a control subject, matched by country, age, sex, and year of birth.

A comparison was made of the survival at up to 30 years for the Olympians and the control subjects. The most important findings were:

Olympic medalists lived, on average, 2.8 years longer than controls,
Gold, silver, and bronze medallists had similar survival rates, and
Endurance athletes enjoyed a larger survival advantage than athletes in the power sports.

The investigators suggested several possible explanations. The Olympians might:

be healthier, due to exercise and better nutrition, and/or
enjoy higher socioeconomic status, that is known to be associated with improved mortality rates, and/or
improved social status, independent of wealth, which might also be associated with improved mortality rates.

So, as Dr. Studdert notes, the ancient Greek warrior, Achilles, had to choose between a short glorious life and a long obscure one,….modern Olympic medalists fare somewhat better!

The Grand Tour Cyclists

The second study received a fair bit of media attention when the results were reported at this fall’s meeting of the European Society of Cardiology meeting. A complete report by Dr. Eloi Marijon and his colleagues from Paris Descartes University was published in last week’s edition of the European Heart Journal.

As many readers will know, the Tour de France is a 3-week cycling race, a so-called Grand Tour, that is is held each July. The race is exceptionally arduous, covering upwards of 2,500 miles and many mountainous ascents, with only 2 days of rest during the event. Moreover, the cyclists who participate in the Tour are typically in their 20’s and 30’s, and have trained many 10’s of thousands of miles of cycling over many years to reach the level of ability to qualify for one of the Tour teams.

We also know now that for a couple decades, at least, there was widespread doping among the elite Tour-level cyclists. The list of doping agents is long and raises the question about long-term harm that might come to riders as a result.

This study focused on 786 French cyclists who participated in at least 1 Tour de France between 1947 and 2012. This group accounted for just about 30% of all riders in the Tour over that time period. The median period of follow-up for the riders was 37.4 years. The cyclists were compared to male individuals in the French general population. The main findings were:

overall, a 41% lower mortality rate than controls,
a survival benefit independent of when (1947-1970 vs. 1971-1990 vs. 1991-2010) the riders raced,
major causes of death since 1968 being cancer, cardiovascular disease, or trauma, but
interestingly, a higher mortality for young (<30 years old) cyclists compared to the controls.

The authors acknowledge several possibilities for the cyclists’ survival advantage, in addition to the healthy effects of exercise:

a selection bias, where only healthy individuals could become elite cyclists, and/or
the advantage may be due to aspects of the cyclists’ lifetimes outside of their short elite cycling career, and/or
other, unmeasured factors (eg, smoking history, nutrition) that might not be similar between the cyclists and the control group.

My Thoughts

I’m not surprised by the findings.

I’ve only met one Olympic medalist and I don’t know any Tour riders. These are very small groups of athletes, for sure.

What can the rest of us learn from these studies?

In the case of the Olympic medalists, there was a small survival benefit of 2.8 years. We know that for many sports, an Olympic career is short. I haven’t seen any epidemiological accounting, but I’d bet that the majority of Olympic medalists lead a healthy lifestyle long after their competing days are over. And certainly, whatever survival advantage they gain must be due not only to their elite sporting career, but also to factors related to their lives afterward. Do they continue to exercise? Do they continue to eat well? Not smoke? There are probably countless factors that are important.

But remember, too, what we’ve learned from studies focused on the question: How little exercise is needed to produce a longevity benefit? We know a lot. And we certainly know that a survival advantage of 2.8 years is easily gained over the general population by making exercise a part of one’s life. This is the basis for the recommendations of 150 minutes of aerobic exercise per week by organizations such as the American Heart Association. You certainly don’t need to be an Olympic medalist. Just get out there and exercise.

In the case of the Tour de France cyclists, it’s interesting that the youngest (<30 years old) riders did not enjoy a survival advantage. What’s different for the youngest riders? In my mind, this raises the possibility of a greater prevalence of underlying heart conditions such as hypertrophic cardiomyopathy or long Q-T syndrome and suggests to me that there is value to cardiac screening programs for young competitive athletes. The finding of an overall 41% reduction in mortality for the cylists is quite large. The benefit is certainly not due solely to competing in the Tour. It probably reflects decades of rather healthy behaviors in general, including exercise, leading up to participating….and then a variety of factors, both health-wise and socioeconomically, after participating in the Tour.

On the bright side, it’s good to see that Grand Tour cyclists don’t have reduced longevity!

2. Exercise is Good!

3. 23 1/2 Hours: What is the single best thing we can do for our health? A great video by Doc Mike Evans.

George W. Bush Gets a Stent

August 21, 2013 By Larry Creswell, MD 1 Comment

We learned from news reports earlier this month that former President George W. Bush was treated with a coronary stent for a blockage in a coronary artery that was discovered during his annual medical check-up. Of course, a great many Americans are treated each day for coronary artery disease (CAD), but Bush’s case draws my attention not only because he’s the former President but also because he’s known to be physically active, especially with cycling.

Bush’s Medical History

The fine details of Bush’s most recent health matters haven’t been made public, and might never be. But we know that while President from 2001 to 2009 he enjoyed comprehensive medical check-ups performed at the Bethesda Naval Medical Center. Each year, short statements were issued by the White House that summarized the President’s health. We can take a look back at some of that reporting.

Before taking office, the President received annual medical check-ups from Dr. Kenneth Cooper at the Cooper Clinic in Dallas, Texas. We know that, at the time he took office in 2009, he had no heart problems and no significant family history of heart disease. He occasionally smoked a cigar, did not drink alcohol, and had typical caffeine intake in the form of diet soft drinks and coffee.

From his examination at age 58 in 2004, we know that: he was 6 feet tall, weighing 200 pounds; his body fat was 18.25%; his resting heart rate was 52 and the blood pressure was 110/60; and the total serum cholesterol level was 170 mg/dL, with a decrease in the LDL (bad cholesterol) and increase in the HDL (good cholesterol) from one year previously. He was noted to have mild calcification of the coronary arteries (presumably based on a screening cardiac CT scan) and both aspirin and a cholesterol-lowering agent were prescribed. At the time, he was running 7 1/2 minute miles on the treadmill and was cycling several times per week.

In 2005 we learned that the President’s weight had decreased by a few pounds and the blood pressure and resting heart rate remained low. He underwent an exercise treadmill test that was normal and his doctors concluded that he was at “very low risk of coronary artery disease.” By 2005 Bush had given up running because of difficulties with knee pain, but continued to be active with cycling and weightlifting.

In 2006 at age 60 he was noted to have an EKG without worrisome abnormalities and a normal stress echocardiogram. Doppler ultrasound studies of the arterial blood supply to the legs was normal and a screening ultrasound of the abdomen showed no evidence of abdominal aortic aneurysm. Laboratory values included: total cholesterol 174 mg/dL, HDL 60 mg/dL, LDL 101 mg/dL, triglycerides 61 mg/dL, and normal values for C-reactive protein (CRP) and homocysteine. Interestingly, it was reported that he was taking no prescription medications despite the 2004 statement about the recommendation for a cholesterol-lowering agent. On the basis of the available information, the President was thought to have “low” to “very low” coronary artery disease risk.

The Coronary Stent

As we all know, Bush left office in 2009. Since then, his medical affairs have been private. So, fast forward to 2013….

We know that Bush went recently for his annual medical check-up at the Cooper Clinic and the following day at Texas Health Presbyterian Hospital was treated with a coronary stent for a blockage in a coronary artery that had been discovered duringn his evaluation. The details have not been made public, but it’s probably fair to assume that he underwent a stress test that was abnormal and that coronary arteriography was organized for the following day, with implantation of the coronary stent at the same setting.

The fact that Bush was treated with a stent for the coronary artery blockage has created a bit of a stir in the medical community. For those who are interested you can read more at:

“Did George W. Bush really need a stent?,” an article by Larry Huston in Forbes.

“The George W. Bush stent case: An incredible teaching opportunity on the basics of heart disease,” a blog piece by Dr. John Mandrola.

“Heart stents still overused, experts say,” an article by Anahad O’Connor at NY Times Well.

Basically, the controversy revolves around the appropriate treatment for asymptomatic patients–those without chest pain, heart attack, etc.–or those with so-called “stable” symptoms–for instance, chest pain with exertion–who are found to have blockage(s) in the coronary arteries. In truth, there has been no public reporting on whether or not Bush had any such symptoms, either with exertion or at rest. And there has been no updated reporting on Bush’s physical activity level or other relevant risk factors for CAD. But information from the best scientific studies suggests that asymptomatic patients and those with “stable” CAD fare no better, with respect to heart attack, stroke, or death, with a stent than without, so long as the best possible medical therapy is provided.

At any rate, this controversy will be one for our community of heart professionals to discuss and sort out.

What Can We Learn?

From the athlete’s perspective, though, Bush’s story reminds us of the importance of coronary artery disease as we age, even if we remain physically active. A few thoughts….

1. The discovery of CAD is almost always a surprise….particularly for an athlete. Nobody is immune from this disease, even if remaining physically active helps guard against it.

2. There is a set of well-established risk factors for CAD. I’ve talked about this issue previously here at the blog. Let’s remember that there are some risk factors that, unfortunately, can’t be modified: increasing age, being male, and having a family history of early CAD. Other risk factors are under our control: obesity, high blood pressure, smoking, abnormal serum cholesterol and lipid levels, diabetes, and physical inactivity. Adult athletes should know where they stand with respect to these risk factors and work to improve any that can be modified favorably. An ongoing relationship with a healthcare provider will offer the necessary framework for this. Periodic measurement of the blood pressure and testing of the serum cholesterol/lipid levels every 5 years are recommended.

3. Our personal situation with CAD will likely change over time. The process in which plaque builds up in the coronary arteries can begin early in our lives. But this process is often progressive as we age. That’s why we say that increasing age is a risk factor. Bush’s story illustrates just how this can happen. In 2004-2006 he had very favorable clinical and laboratory data regarding his risk of CAD, including a normal stress echocardiogram in 2006. Yet today we know that an important blockage had formed, or more likely progressed, in the interim. It’s important, then, to periodically re-visit our circumstance with CAD.

4. Warning signs are important. Important blockages in the coronary arteries often lead to symptoms of angina–chest pain/discomfort or perhaps difficulties with breathing. When angina occurs with exertion, we call it exertional or stable angina. When angina occurs at rest, we call it unstable or rest angina. Either form of angina should prompt timely evaluation. That evaluation may take the form of stress testing or coronary arteriography to look for blockages in the coronary arteries. Unfortunately, there are some patients whose first sign of trouble is a heart attack, or myocardial infarction. This can occur in athletes and non-athletes, alike.

Related Posts:
1. Coronary Artery Disease: The Essentials
2. Two Stories, Two Endings, a blog post about endurance athletes and CAD.
3. In the News: Coronary Plaque Build-up in Marathoners

Cyclist’s Account of Atrial Fibrillation

February 24, 2010 By Larry Creswell, MD 3 Comments

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.