Diagnosing and sports counselling of athletes with myocarditis

Myocarditis is defined as an inflammation of the heart muscle and its presentation, especially in athletes, is heterogeneous. Underlying causes include in most of the cases viruses, and less often bacteria, toxins, vasculitic diseases or pharmaceutical agents. Cardiac magnetic resonance (CMR) imaging is the primary imaging tool to diagnose myocarditis following laboratory test, electrocardiogram and echocardiography. In certain cases, endomyocardial biopsy is required, especially in unclear cases with reduced systolic left ventricular ejection fraction. Although, athletes and sport physicians face the dilemma of significant performance decline in competitive athletes against the risk of adverse cardiac events, currently abstinence from competitive sports is recommended for at least 3–6 months in myocarditis. Sports recommendations are currently based mainly on autopsy studies and experts’ opinions and better risk stratification tools are imperatively needed. New tissue characterization methods, namely T1 mapping and T2 mapping in CMR continue to improve sensitivity and specificity of diagnosing myocarditis and may further enhance individual risk assessment. In the future, sports physicians may be able to rely more on these novel noninvasive tissue characterisation methods in risk stratification and sports restriction recommendations of athletes with suspected myocarditis.