Atrial Flutter Leads to Diagnosis of Metastatic Melanoma Involving the Heart.

A 61-year-old male patient, who was previously healthy, presented to the emergency department with weakness. He had tachycardia at 180/minute with normal blood pressure. An electrocardiogram revealed atrial flutter. He was started on an intravenous diltiazem drip. Transthoracic echocardiography revealed 2 hyperechoic masses within the left ventricle; 1 measured 1.2 × 0.74 cm, and the other was 3 × 1.4 cm. The right ventricle also showed a mass of 1.1 × 1 cm (Fig. 1). The masses were suggestive of possible metastatic disease. A computed tomographic scan of the chest, abdomen, and pelvis showed diffuse metastatic disease to the lung, liver, spleen, and mesentery; erosive changes in the left scapula with a large left scapular mass; and hypoattenuating masses within the left ventricle (Fig. 2A and 2B). Skin examination revealed a lesion in the right axilla that was concerning for melanoma (Fig. 3). The patient had a biopsy that confirmed the diagnosis of metastatic melanoma positive for a BRAFV600E mutation. The patient opted for comfort care after the oncology team discussed several treatment options.The heart's involvement by melanoma is not common on presentation and even goes unrevealed in some patients. Glancy et al1 reviewed autopsies in 70 patients with melanoma and demonstrated that cardiac metastases occurred in up to 65%. In general, cardiac metastasis is unusual and has been described in less than 10% of melanoma cases.2 Cardiac metastasis is not commonly revealed because most patients lack cardiac symptoms. Very few patients present with cardiac symptoms, such as this patient did, that reveal the diagnosis of metastatic melanoma.