A Case of Biventricular Thrombus and Fulminant Myocarditis after Severe Acute Respiratory Syndrome Coronavirus 2 Messenger RNA Vaccination

Abstract

　A 47-year-old woman was transferred to our hospital after experiencing cardiogenic shock and undergoing intra-aortic balloon pumping. The patient had received the first dose of the messenger RNA (mRNA)-1273 vaccine (Moderna) before hospitalization. Echocardiography revealed a reduced left ventricular ejection fraction and massive biventricular thrombi. Cardiac magnetic resonance imaging suggested myocarditis. After the ventricular thrombus was resolved, an endomyocardial biopsy confirmed the diagnosis of myocarditis. Finally, we terminated the intravenous inotrope therapy. Although fulminant myocarditis with biventricular thrombi after mRNA vaccination for coronavirus disease 2019 is extremely rare, post-vaccination myocarditis should be considered in the differential diagnosis of a cardiogenic shock.