Cardiac Imaging and Stress Testing Asymptomatic Athletes to Identify Those at Risk of Sudden Cardiac Death

Sudden cardiac death in young athletes is rare but tragic. The cardiology community is faced with the challenge of providing a sensible strategy for the prevention of SCD while simultaneously reaffirming that the benefits of regular exercise far outweigh potential risks. At present, there is a broad range of screening recommendations dependent upon country, sporting discipline, and competition level. While much recent debate has focused on the efficacy of screening with electrocardiography, a number of sporting bodies also mandate the inclusion of exercise testing and echocardiography in screening protocols. Cardiac magnetic resonance imaging, coronary calcium scoring and computed tomography coronary angiography have also been promoted as potentially valuable screening tools for competitive athletes. This review will examine the controversial topic of utilizing cardiac imaging for athlete pre-participation screening. Specifically, the limitations of screening for relatively rare disorders using imaging tools with uncertain or imperfect accuracy will be addressed. Current evidence suggests that the accuracy of all cardiac imaging modalities is insufficient to justify their use as primary screening modalities in athletes. Atypical findings such as marked cardiac dilation, reduced deformation, or small patches of delayed gadolinium enhancement may be commonly encountered in well-trained athletes, but, at present, the prognostic significance of such findings is unknown. Resulting uncertainty for the clinician and athlete has the potential for psychological stress, further testing, and unnecessary exclusions from competition. However, these concerns must not be confused with the extremely useful applications of cardiac imaging for the assessment of athletes with symptoms, an abnormal electrocardiogram or a positive family history. As modern imaging further enhances our understanding of the spectrum of athlete's heart, its role may expand from the assessment of athletes with suspected disease to being part of comprehensive pre-participation screening in apparently healthy athletes. (c) 2013 by the American College of Cardiology Foundation