Multichamber Involvement of Metastatic Cardiac Melanoma

Abstract

A 30-year-old man with a history of an in-situ melanoma of the forehead was referred for cardiac evaluation because of tachycardia and elevated levels of serum troponin. The transthoracic echocardiogram revealed multiple masses attached to the walls of both ventricles and the right atrium (RA). A large mass was occupying almost one third of the right ventricle (RV), resulting in reduction of the end-diastolic RV volume and tachycardia. A cardiac magnetic resonance imaging confirmed multifocal myocardial infiltration and intracavitary masses and excluded the presence of thrombus in any of the cardiac chambers. Diffuse metastatic involvement in the liver, the spleen, and the brain by computed tomography precluded surgical management. Being BRAF-unmutated, the patient was initially treated with a combination of nivolumab and ipilimumab. One month later, the cardiac metastases in RA and left ventricle were unchanged on echocardiogram, while the tumor in RV was enlarged occupying the majority of the chamber, resulting in further reduction of the cardiac output and tachycardia. The treatment was changed to a combination of dacarbazine and carboplatin, but the patient eventually died two months later. Heart is not a common metastatic site of melanoma and cardiac involvement is usually clinically silent making ante mortem diagnosis difficult. Multimodalidy imaging plays a pivotal role in the diagnostic work up. Cardiac melanoma metastases indicate an advance stage disease with poor prognosis.