Physician attributes sudden death in young athletes to inherited heart diseases

The sporting world lost two young athletes this month to sudden cardiac death. Preliminary autopsy reports indicate that Chicago Bears defensive end Gaines Adams, 26, and Southern Indiana center Jeron Lewis, 21, both had enlarged hearts at the time of their death.

Lewis collapsed and died during a basketball game on Jan. 14. Adams died Jan. 17 after suffering cardiac arrest in his home.

What causes a young, fit athlete to die suddenly? A close look at the family tree will usually reveal the answer, according to Charles Hong, M.D., director of Vanderbilt's Inherited Heart Disease Clinic.

"Precise figures vary, but it's clear that the top causes of sudden death in a young athlete are inherited heart diseases," he said. These include hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy.

The No. 1 cause is hypertrophic cardiomyopathy, a thickening or enlargement of the heart. It's what killed Ryan Shays, the 28-year-old U.S. long-distance runner who died at the Olympic Marathon Trials in 2007. Though the unexpected collapse and death of a young athlete in prime physical condition garners national attention, it is, fortunately, a very rare event. But sudden cardiac death in the general population is far more common.

Hypertrophic cardiomyopathy affects up to one in 500 people, Hong said.

"Most people don't know they have it because many don't have symptoms. A lot of pro and varsity sports teams actually look for these conditions, but it is not standard of care for the average recreational athlete."

Hypertrophic cardiomyopathy and the other leading cause of sudden cardiac death, ventricular arrhythmia, are usually inherited conditions. Anyone with a family member who died suddenly or died young from unexplained causes is at much higher risk for sudden cardiac death, especially during intense exercise. Those with a family history of this nature should consider a more detailed heart evaluation, including an electrocardiogram (ECG) and an echocardiogram (heart ultrasound), and should seek medical expertise before participating in strenuous exercise or a competitive sport.