Abstract Background Viral genesis is the most common cause of myocarditis. COVID-19-associated myocarditis seems to be a notable extrapulmonary manifestation, which may result in the need for a different treatment. There has been no positive polymerase chain reaction (PCR) testing of SARS-CoV-2 in heart specimens, thus far. Case summary A 48-year-old male patient presented with fever, dyspnoea, and haemoptysis. Laboratory findings showed highly elevated inflammatory and cardiac damage markers. Thoracic computed tomography (CT) revealed bilateral, patchy peripheral ground-glass opacities with a crazy-paving pattern, focal consolidations, and mild pleural effusions. Cardiac imaging with echocardiography and magnetic resonance imaging (MRI) detected a reduced biventricular function. MRI additionally showed myocardial oedema and late gadolinium enhancement. Lung and heart biopsies were performed, revealing alveolitis with necrosis and acute lymphocytic myocarditis. Testing for usual cardiotropic viruses was negative, and no aspects of vasculitis or granuloma could be found. Due to fulfilling the criteria, the patient was diagnosed with rheumatic vasculitis. Treatment with cyclophosphamide and steroids was initiated. Later, the patient reported a history of travel to Tyrol in mid January. Consequently, PCR testing for SARS-CoV-2 was performed, which was positive in the heart specimen. Immunosuppressive treatment was discontinued. During a follow-up visit at the end of April, the patient’s recovery was stable. Discussion In COVID-19 infections, myocardial inflammation can be present as an extrapulmonary manifestation. Positive PCR testing confirms myocardial invasion of the virus. Imaging and laboratory studies correlate with the histopathological findings, and thus should be performed in COVID-19 patients who are suspicious for myocarditis. Supportive treatment with steroids may be useful in these patients.