Sudden death in young athletes.

The sudden, unexpected death of four young athletes and the findings in their hearts at the time of necropsy were studied. Two athletes had anomalous left coronary origin from the anterior valsalva's sinus. In these cases, the sharp left-ward passage of the coronary artery along the aortic wall may cause the entrance into the left coronary system to be slit-like. There may be an increased expansion of the pulmonary artery and aorta with increased cardiac activity during exercise. Consequently, the left coronary artery may stretch and form a flap-like closure of the orifice of the left coronary, with sudden, fatal myocardial ischemia. The third young athlete had hypertrophic cardiomyopathy that could account for his sudden death; however, the cause of sudden death of the fourth could not be explained despite careful studies.