Does sports activity enhance the risk of sudden cardiac death?

Vigorous physical exercise may precipitate acute fatalities in both adults and young competitive athletes with concealed heart diseases. However, the risk-benefit ratio of physical exercise differs among these two age groups. In adults, physical activity can be regarded as a 'double-edged sword': vigorous exertion increases the incidence of acute coronary events in individuals who did not exercise regularly, whereas habitual physical activity reduces the overall risk of myocardial infarction and sudden coronary death by preventing development and progression of atherosclerotic coronary artery disease. On the other hand, in adolescents and young adults sports activity is associated with a significant increase of the risk of sudden death. Sport is not per se the cause of the enhanced mortality in this age group; rather, it acts as a trigger of cardiac arrest in those athletes who are affected by silent cardiovascular conditions, mainly cardiomyopathy, premature coronary artery disease and congenital coronary anomalies, which predispose to life-threatening ventricular arrhythmias during physical exercise. J Cardiovasc Med 7:228-233 (C) 2006 Italian Federation of Cardiology.