The athlete projects the ultimate image of well-being in the health status 
spectrum. Nevertheless, exercise-related sudden cardiac death (SCD) is an 
uncommon, yet tragic, occurrence. Exercise-related SCD is defined by symptoms 
that arise within 1 hour of participation in sport. The major mechanisms 
involved in exercise-related SCD are related to haemodynamic and 
electrophysiological changes brought about by exercise in the susceptible 
individual. Fatal arrhythmia seems to be the most common mechanism of death. 
Between 1 and 5 cases of SCD per 1 million athletes occur annually. In young 
athletes (<35 years old), the majority of these cases are caused by defined and 
hereditary cardiovascular disorders. Among other aetiologies, hypertrophic 
cardiomyopathy and coronary artery anomalies are most common in this group. In 
older athletes (>35 years old), sudden death is usually associated with 
atherosclerotic cardiac disease. A problem for identifying athletes at risk for 
SCD is that the athlete's heart undergoes adaptive changes in response to 
regular physical exercise. Alterations in cardiac function influence the 
physical examination, the electrocardiogram and the echocardiogram. Because of 
these characteristic 'abnormalities' of the athlete's heart, it is often 
difficult to distinguish physiological adaptations from pathophysiological 
processes. Although studies and observations have helped to clarify the 
cardiovascular pathology responsible for SCD in young, apparently healthy 
individuals, effective methods for preventing SCD and identifying and screening 
athletes at risk remain elusive. Problems with routine comprehensive screening 
of athletes include the limitations inherent in the predictive value of 
available diagnostic procedures and the cost of testing large populations. The 
variation from normal cardiac physiology found within the athletic population 
and the rarity of SCD in athletes means that elaborate screening to determine 
individuals at risk is neither practical nor cost effective. A thorough 
assessment of pertinent family and medical histories, cardiac auscultation of 
young athletes, evaluation of exercise-induced symptoms and education of older 
athletes to the symptoms of cardiac ischaemia are all essential to primary 
prevention of SCD in the athletic population. Until reliable methods can 
accurately identify those athletes at risk for SCD, broad recommendations are 
available to help guide the management and participation in sports of athletes 
with cardiovascular disease.