I have just returned from attending a course on the “Prevention of Sudden Cardiac Death in Athletes,” hosted by the University of Washington medical school in Seattle.  It was a terrific conference at which academic leaders in the field gave updates on the latest research.

Dr. Aaron Baggish, from the Massachusetts General Hospital in Boston, summarized two recent studies that have persuasively shown that coronary calcifications are more common in long-term endurance athletes compared to more sedentary controls.

When the studies were published this past summer, Dr. Baggish was asked to write an editorial commentary to share his perspective.  That editorial was provocatively subtitled “Hearts of Stone.”  The phrase refers to the appearance on CT scans of hearts with heavily calcified arteries as shown in this image:

Calcium in coronary artery detected by CT scan.
Image attribution: Wikimedia Commons

Background

In the last several years, a few reports were published suggesting that endurance athletes may be more prone to having build-up of plaque and calcium in their coronary arteries.  Those reports presented a paradox, because we also know beyond any doubt that regular, moderate level exercise promotes cardiovascular health and longevity.  The studies raised the concern that exercise could be harmful after a certain point.Read more

Image attribution: Julian Mason/Flickr.

Professional athletic trainer and sports journalist Ian MacMahan asked us that question as part of an article he published in The Atlantic Monthly magazine.

McMahan reported on recent research that raises concerns about ultra-endurance sports carried to an extreme level for many years.  Such an exercise regimen increases one’s chance of having arrhythmia, such as atrial fibrillation, and may also cause scarring in the ventricle of the heart.

Some cardiologists have sounded alarm bells, comparing such exercise regimens to a “toxin.”  In my opinion, it is not yet clear if long-term, high-intensity exercise alone is the cause of the problem, or if those affected have other factors that come into play.  Nevertheless, the research should not be dismissed.   Here are some highlights:Read more

Last Sunday, an experienced marathon runner in his mid-50’s collapsed a few yards from the finish line during the Road2Hope half-marathon in Hamilton, Ontario.  Regrettably, the paramedics were unable to resuscitate him.  This unfortunate story illustrates the rare but tragic phenomenon of exercise-induced sudden cardiac arrest.Read more