A 19-year-old man had a documented ventricular fibrillation during a football match. He was a top-level athlete, and after successful resuscitation, he was extensively studied. Electrolytic disturbances, long QT syndrome and nervous mechanisms were all ruled out. Right and left ventriculography, coronary angiograms, electrophysiologic study and endomyocardial biopsy all proved normal. A beta-blocker was empirically given in the absence of any reliable test to guide therapy more scientifically.