An Italian study looked at the rate of sudden cardiac deaths (SCD) in athletes and produced some interesting results. The relative risk of cardiovascular sudden cardiac death (SCD) in athletes aged 12 to 35 years was 2.5 times higher than nonathletes. The overall annual rate of SCD in US athletes is 1 in 50,000 to 200,000.
The most common cause of SCD in athletes is hypertrophic cardiomyopathy (HCM), followed by coronary artery anomalies and commotio cordis. SCD in athletes most often occurs during or shortly after intense training or competition. SCD in athletes show a male predominance (>90%), a disproportionate number of HCM-related SCDs in black versus white athletes, and a much higher incidence of SCD in certain sports, such as basketball and football.
Source: Sports Health, November-December 2009