A case of mitral valve prolapse with increased risk for sudden cardiac death in an athlete

Mitral valve prolapse (MVP) is the most common valvular abnormality in athletes. The natural history of MVP is generally benign. However, MVP has been associated with an increased risk for arrhythmic sudden cardiac death (SCD). Most of these patients did not have severe mitral regurgitation. Moreover, ventricular and supraventricular arrhythmias are common in athletes with MVP. Therefore, risk stratification for SCD is particularly challenging in athletes diagnosed with MVP. There are several markers that may be associated with heightened risk of SCD including family history of SCD, T-wave inversion in the inferior leads on the 12-lead ECG, ventricular arrhythmias on ambulatory ECG, echocardiographic measures such as severe mitral regurgitation, mitral annular disjunction (MAD), left ventricular systolic dysfunction as well as myocardial fibrosis in the left ventricular inferolateral basal region and papillary muscles detected by magnetic resonance imaging. We report the case of an asymptomatic cyclist with MVP associated with MAD and frequent ventricular ectopic beats at exercise stress test. Subsequent cardiac magnetic resonance imaging revealed myocardial fibrosis in the left ventricular inferolateral basal region and papillary muscles, identifying athletes with MVP and higher risk of SCD. Based on these findings, the athlete was restricted from competitive sport.