Ventricular Tachycardia in a Young Athlete With Prior Myocarditis and MYL2 Mutation.

backgroundMyocarditis and inherited cardiomyopathies are important causes of malignant arrhythmias in young athletes. CASE SUMMARY: A 23-year-old female competitive soccer player presented with exertional chest discomfort, dizziness, and syncope. Troponin elevation and cardiac magnetic resonance with subepicardial late gadolinium enhancement of the inferolateral wall were thought to be consistent with acute myocarditis. She recovered after activity restriction and had normal follow-up magnetic resonance imaging, echocardiogram, and cardiopulmonary exercise testing. During monitored return to play, she developed a 42-second episode of polymorphic ventricular tachycardia while sprinting, leading to subcutaneous implantable cardioverter-defibrillator placement for secondary prevention. Genetic testing revealed a pathogenic MYL2 variant; her mother, brother, and sister carry the same mutation. DISCUSSION: This case highlights the overlap between myocarditis, genetic susceptibility, and exercise-triggered polymorphic ventricular tachycardia, and the challenges of risk stratification and return-to-play decisions in genotype-positive athletes with prior malignant arrhythmia. TAKE-HOME MESSAGE: Myocarditis may unmask occult genetic substrates, and return-to-play decisions require individualized shared decision-making in the context of incomplete risk data.