T HE PURPOSE of this paper is to emphasize the occurrence of systemic embolism as a sign, often the presenting one, of cardiac myxomas. The literature is reviewed and a new case reported. Primary cardiac tumors are rare. They have been found in 0.05 per cent of autopsied material; secondary metastatic cardiac tumors occur in 0.6 per cent of cases.1 The antemortem diagnosis of primary cardiac tumors is rarer still, but with the advent of angiocardiography and adequate technies for their surgical removal, the consideration of this diagnosis has become critical. The most common primary tumor is the myxoma. This basic tumor has a broad spectrum of appearance, namely, fibromyxoma, myxohemangioma, myxohemangioendothelioma, etc. The myxoma accounts for 50 per cent of all primary tumors. Approximately 75 per cent of these occur in the left atrium,2 usually in the region of the rim of the fossa ovale. Approximately 20 per cent occur in the right atrium; the rest may arise on a valve leaflet, from the ventricular endocardium, or from the wall of the pulmonary artery.3 Cardiac myxomas have been reported in the age group of the newborn4 to 70 years.5 The greatest incideiice is between 30 and 60 years.2 Thirty-two cases demonstrating embolization have been previously reported. Of these, 29 had their site of origin in the left atrium,5 32 one in the right atrium,33 one in the left ventriele,34 and one in the root of the pulmonary artery.3 The tumor arising in the root of the pulmonary artery was a fibromyxosarcoma. The remainder were myxomas. The sites of .~~~~~~~~~~~~~~~~~~~~~~~~ Fromii the Departments of Medicinie anid Surgery, Presbyterian-St. Luke's Hospital, and the University of Illinois College of Medicine, Clicago, Illinois.