A 24 year old man collapsed, clutching his chest, while pushing a motor car. Resuscitation attempts were unsuccessful. He had previously lost consciousness while weightlifting. There was no history of drug abuse.

At postmortem examination the heart weighed 430 g, normal for an 83 kg man. Cut section of the myocardium showed a 4 cm area of fibrosis in the lateral free wall of the left ventricle (fig 1). The epicardial coronary arteries had normal origin and no stenoses. The cardiac valves were normal. There was severe pulmonary oedema (right lung 800 g, left lung 550 g).