A Case of Acute Myocarditis During Treatment With Anti-PD-1 Antibody Nivolumab in a Melanoma Patient

Abstract

A 69-year-old woman presented to our hospital with general malaise and tachycardia. She had been treated with an immune checkpoint inhibitor nivolumab (anti-PD-1 antibody) for advanced melanoma of the right eye with liver and bone metastasis. Electrocardiogram showed ST-segment elevation in inferior leads in association with elevated myocardial biomarkers (creatine kinase 728 IU/L, creatine kinase MB isozyme 487 IU/L, and cardiac troponin T 1.60 ng/dL). Echocardiography showed diffuse, moderate hypokinesis of the left ventricle. Emergent coronary angiography revealed normal epicardial coronary arteries and we suspected acute myocarditis as an underlying disease. Left ventricular function was gradually deteriorated with the development of pulmonary congestion, and we started prednisolone at 100 mg/day. Thereafter, the levels of cardiac enzymes declined and left ventricular ejection fraction was gradually improved from 30% to 48%. Myocardial biopsy performed before the treatment with prednisolone demonstrated infiltration of lymphocytes that were CD8 positive and CD4 negative. Real-time PCR and immunohistochemical analysis of biopsied samples for cardiotropic viruses were negative. Immune checkpoint inhibitors are now used for the treatment of advanced melanoma and lung cancers, being known to cause immune-related adverse effects such as thyroiditis, pneumonitis, and pancreatitis. To the best of our knowledge, this is the first reported case of acute lymphocytic myocarditis related to nivolumab treatment.