[A case of cardiac lipoma in the ventricular septum].

A 45-year-old man was admitted because of systolic murmur after routine medical checking. Echocardiography and cardiac catheterization revealed a large mass in the ventricular septum which bulged into right ventricular cavity with pressure gradient of 29 mmHg. The diagnosis of cardiac lipoma was made by CT scanning which showed the mass with attenuation values of -94 Hounsfield units. MR imaging demonstrated the mass with high signal intensity which corresponded to that of subcutaneous fatty tissue. The tumor was resected through the right ventricular incision with the use of cardiopulmonary bypass. It was yellow, elastic soft, sized 6.5 x 4.3 x 3.5 cm, and weighed 44.7 g. On histological examination, the tumor was composed of mature fatty tissues contained with myocardial fibers. After operation, he had split of the ventricular septum, which was closed primarily after removal of the lipoma, and left-to-right shunt. Patch reinforcement was performed at the right ventricular side of the septum on the postoperative 18th day. Postoperative electrocardiogram showed left axis deviation and complete right bundle branch block. This finding seems to be resulted from injury to the anterior branch of left bundle. The postoperative course was uneventful. This patient is the second case of removal of cardiac lipoma in the ventricular septum on review of the literature in Japan.