The tragic stories, it seems, keep on coming. A 38-year-old pediatrician and mother collapsed and died while running on a treadmill in Maryland. A 17-year-old Boston boy died suddenly during a pickup basketball game. Last year, National Public Radio compiled a list of professional athletes who suffered sudden cardiac arrests in the last few years, including an Atlanta Hawks center, a Denver Broncos running back, and a Toronto Blue Jays pitcher.
Preventing sudden cardiac death in athletes isn't a new challenge. Most doctors worldwide agree on how to do it. And yet authorities such as the American Heart Association have consistently opposed widespread adoption of the measures necessary to combat the problem. The fact that Americans continue to accept the preventable sudden deaths of athletes says a lot about our complacent attitude toward the problem. We don't lack good science. We lack the motivation to act on it.
The leading cause of sudden death in American athletes is a genetic disorder called hypertrophic cardiomyopathy, which by some estimates affects roughly one in 500 people. Like weeds that overrun an unkempt yard, the heart muscle fibers proliferate rapidly and in a disorganized manner, often leading to a tripling or quadrupling in heart size during adolescence (see a picture here). People with HCM usually have no idea this is happening until they're exercising one day and the electrical system in the heart suddenly fails. The heart takes on the appearance of a bag of worms struggling to get free (a problem called ventricular fibrillation), and cardiac arrest occurs.
Back in the 1970s, the government of Italy began a radical experiment and passed the Medical Protection of Athletes Act, which mandated that every athlete between 12 and 35 years of age get a physical exam and an electrocardiogram, a test that records on paper the athlete's heart rhythm pattern for a few seconds. The EKGs yielded a bonanza of interesting findings, and many athletes were found to have previously unsuspected heart problems that disqualified them from high-intensity participation. In 2006, researchers determined that sudden death in Italian athletes had dropped by an incredible 90 percent—because of the reduction in deaths due to HCM as well as some rarer conditions detected by the test.
Typically, American athletes get screened by a simple history and physical exam but no testing like an EKG. That's not good enough. In a review of 158 sudden cardiac deaths in young athletes, for example, only 3 percent were suspected of having heart problems based on the history and physical exam alone. In the largest study of seemingly normal American high school athletes, EKGs found serious cardiac problems in about one in 350 teens—yet the history and physical missed almost 19 out of 20 of these conditions. The principal author of the American Heart Association guidelines on athletic screening wrote that an athlete's history and physical exam alone "lacks sufficient power to identify important cardiovascular abnormalities consistently."