Myocarditis in Athletes Is a Challenge: Diagnosis, Risk Stratification, and Uncertainties

Presentation of myocarditis in athletes is heterogeneous and establishing the diagnosis is challenging with no current uniform clinical gold standard. The combined information from symptoms, electrocardiography, laboratory testing, echocardiography, cardiac magnetic resonance imaging, and in certain cases endomyocardial biopsy helps to establish the diagnosis. Most patients with myocarditis recover spontaneously; however, athletes may be at higher risk of adverse cardiac events. Based on scarce evidence and mainly autopsy studies and expert's opinions, current recommendations generally advise abstinence from competitive sports ranging from a minimum of 3 to 6 months. However, the dilemma poses that (un)necessary prolonged disqualification of athletes to avoid adverse cardiac events can cause considerable disruption to training schedules and tournament preparation and lead to a decline in performance and ability to compete. Therefore, better risk stratification tools are imperatively needed. Using latest available data, this review contrasts existing recommendations and presents a new proposed diagnostic flowchart putting a greater focus on the use of cardiac magnetic resonance imaging in athletes with suspected myocarditis. This may enable cardiac caregivers to counsel athletes with suspected myocarditis more systematically and furthermore allow for pooling of more unified data. To modify recommendations regarding sports behavior in athletes with myocarditis, evidence, based on large multicenter registries including cardiac magnetic resonance imaging and endomyocardial biopsy, is needed. In the future, physicians might rely on combined novel risk stratification methods, by implementing both noninvasive and invasive tissue characterization methods.