Electron Beam CT in the Diagnosis of Recurrent Cardiac Lipoma

Abstract

A 34-year-old woman had undergone resec-tion of a tumor infiltrating her left ventricle 13years earlier. The tumor was histologicallyclassified as a lipoma. After the operation, thepatient developed persistent ventricular ar-rhythmia with recurrent ventricular flutter thatnecessitated the insertion of an automatic im-plantable cardioverter–defibrillator. The chestradiograph obtained at that time showed bor-derline enlargement of the heart and a shoul-derlike widening of the cardiac silhouettetoward the left side (Fig. 1A). Multiplanartransesophageal echocardiography (SSA-270A; Toshiba, Tokyo, Japan) depicted an an-teroapical structure with an inhomogeneousechotexture. We performed transthoraciccontrast-enhanced echocardiography using10 mL of galactose palmitic acid–coated mi-crobubbles (4 g, 400 mg/mL, SHU 508A,Levoist; Schering, Berlin, Germany) withsecond harmonic imaging (HDI 3000cv; Ad-vanced Technology Laboratories, Bothell,WA). The resultant images showed a hypo-echoic nonenhancing epicardial tumor ex-tending into the myocardium of bothventricles (Fig. 1B). Because we suspectedthat the patient had recurrent cardiac lipoma,we performed electron beam CT (C150;Imatron, San Francisco, CA; ECG trigger-ing, single-slice mode, 3-mm slice thickness,3-mm table feed, 100-msec exposure time,IV bolus injection of contrast material) thatrevealed a tumor that had the density of fatnear the heart base at the left ventricle. Thetumor had a maximal extension of 5 × 3.5 cmand showed signs of infiltration into the apexand lateral wall of the left ventricle, the sep-tum, the right ventricular myocardium, andthe heart base (Figs. 1C–1F).