Oregon Public Broadcasting

An autopsy conducted Friday found that OSU defensive tackle, Fred Thompson, died of an enlarged heart.

Oregon State Medical Examiner, Dr. Karen Gunson found the 19-year-old suffered hypertrophic cardiomyopathy -- or an enlarged heart.

Fred Thompson, Courtesy OSU.

An autopsy conducted Friday found that OSU defensive tackle, Fred Thompson, died of an enlarged heart.

Oregon State Medical Examiner, Dr. Karen Gunson found the 19-year-old suffered hypertrophic cardiomyopathy -- or an enlarged heart.

Gunson says that during strenuous exercise, such a heart can suffer an arrhythmia -- that is a disruption of the natural beating.

She says the condition can kill young athletes, who seem completely healthy but whose hearts fail during heavy exercise.

"You have an enlarged heart or an increase in the size of the heart in high performance athletes. It's just like any other muscle, if you use it, you built it up. But that can go to extreme. That can cause the cardiomyopathies which Fred had is an abnormal and unhealthy build up of the cardiac muscle, more than what you need for athletic endeavors," Gunson said.

Gunson is not sure if Thompson inherited his condition.

His father died of a heart attack. But Gunson thinks that was because of blocked arteries.

She says an enlarged heart can be found in a routine chest x-ray or an EKG.