Acute Myocarditis Mimicking Hypertrophic Cardiomyopathy in Marfan Syndrome and Morphologically Abnormal Mitral Valve

A 40-year-old man with Marfan syndrome presented with chest pain and troponin elevation. Urgent echocardiography was suggestive of hypertrophic cardiomyopathy, but cardiovascular magnetic resonance identified features of acute myocarditis. Repeated imaging 4 months later showed resolution of septal thickness, confirming acute myocarditis. (Level of Difficulty: Intermediate.)