CORVALLIS, Ore. -- A medical examiner says an Oregon State defensive tackle who collapsed and died during a pickup basketball game had an enlarged heart.

Fred Thompson died Wednesday.

Dr. Karen Gunson said Friday that the 19-year-old had increased thickness of the heart muscle, which can cause an irregular heartbeat during strenuous exercise.

She says the condition is a common cause of death in young athletes who seem completely healthy but die during heavy exercise.

Thompson's family asked that his skin, bones and eyes be donated.

Thompson spent this season recovering from shoulder surgery.

His heart condition is known formally as hypertrophic cardiomyopathy.