HCM: The Silent Disease Plaguing Young Athletes

By Jessica Ross, Heart1 Staff

Hypertrophic cardiomyopathy (HCM) causes approximately 200,000 American deaths annually, the vast majority occurring in individuals under thirty. In recent years, Boston Celtic Reggie Lewis, Olympic figure skater Sergei Grinkov, Chad Butrum, and Adam Lemel all tragically died of this so-called “silent” disease while engaging in athletic activity. The memory of such abrupt loss in young athletes has fueled a growing trend to offer echocardiograms to student athletes and provide defibrillators at school athletic facilities.

Hypertrophic cardiomyopathy, a genetic cardiac disease that has a relatively high frequency of 1:500 among the general population, is responsible for the majority of sudden cardiac deaths in young people. In most patients, HCM confers little or no disability, and normal life expectancy. Indeed, it is the very assymtomatic nature of the disease that makes it so potentially dangerous: the first indication of HCM often comes when an athlete collapses on a playing field. Generally, the disease is diagnosed by echocardiogram, which can detect the characteristic left ventricular wall thickening of the heart. For this reason, there has been widespread support for including echocardiograms in pre-season health screenings for student athletes. Unfortunately, such screenings can cost up to $2000 per athlete, and would ideally need to be conducted regularly over the athlete’s career. Moreover, there is very little echocardiographic data for adolescent athletes, for whom the risk of sudden death from HCM is highest. (Sharma et. al)

Fortuitously, a number of physicians, non-profit organizations, and politicians have stepped forward to address this critical void. Notably, the Chad Foundation for Athletes and Artists and the Living Heart Foundation have joined together in recent years to offer free cardiovascular screening to athletes in pilot programs across California, Massachusetts, New York, Maryland, and Washington, DC. In the results of one such program, conducted on the Columbia University varsity football team, the Living Heart Foundation found that “over one-half of these college students had one or more abnormalities detected by the … screening process.” The Columbia program used an Acuson echocardiography system, which is light, easily portable, and capable of a wide variety of echocardiograph applications.

The Chad and Living Heart Foundation are joined in their mission by a growing number of like-minded organizations and individuals nationwide. Texas physician Dr. Maxwell Axler alone has screened approximately 600 student athletes for a minimal fee of $30. His efforts, using SonoSite Inc. echocardiograph equipment, have yielded eight abnormal results, of which three were considered true positives. (Rundle, Wall Street Journal) Although some view the number of false positives sometimes generated by the tests as problematic, to most the opportunity to save even one life is a worthwhile effort.

In addition to efforts making echocardiograph screening more affordable, studies by Dr. Barry J. Maron of the Minneapolis Heart Institute Foundation have served to illuminate the characteristics of a healthy adolescent athlete’s heart. Notably, Maron’s study determined that "[t]rained adolescent athletes demonstrated greater absolute [left ventricular wall thickening] LVWT compared with non-athletes." Specifically, the research of Maron and colleagues found that male adolescent athletes with LVWT of more than12mm, and female adolescent athletes with more than 11mm, constitute the populations at risk for HCM (assuming a non-dilated left ventricle). Assisting in this work, data from the Chad and Living Heart Foundations will be assembled into the "National Cardiovascular Screening Lifestyle Initiative," (NCSLI) designed to collect data on cardiovascular research in young people.

Parallel to the echocardiogram movement, automatic external defibrillators (AEDs) are now in place at many school athletic facilities. During a heart attack or other cardiac emergency, the heart’s rhythm is dangerously disrupted. An AED senses such rhythmic abnormalities, and can restore normal function by sending a shock through the victim’s chest. By mid-2001, all fifty states had enacted defibrillator laws or regulations. Some states, such as New York, now require AEDs in their schools. Congress has also approved legislation to increase access to defibrillators for those living in the rural areas of several states. More recently, in June 2002, President Bush approved the ADAM Act, which assists in providing schools with the equipment and technical guidance to save cardiac arrest victims. Cosponsored by Senators Russ Feingold (WI) and Susan Collins (ME), the act is patterned after Project ADAM, in memory of Adam Lemel, who collapsed and died at a high school basketball game.

The presence of AEDs at school sites have already saved numerous lives as reported in recent media, and will doubtlessly continue to do so. In turn, while the ability of organizations such as Chad to fund echocardiograms for athletes has been injured by the recent economic downturn, Chad President Arista notes that the organization "looks forward to continuing [their] work… to help save young lives through screenings."

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