[Enlarged heart caused by massive subepicardial lipomatosis with idiopathic dilatation of the right cavities].

The case is reported of a man of 48 with known longstanding gross cardiomegaly which was completely asymptomatic. Angiocardiography and coronary arteriography showed dilatation of the right side of the heart, and especially of the auricle. In addition, the ventricle was separated from the diphragm by a transparent non-fluid area. At operation, gross dilatation of the right atrium was confirmed, but no causative lesion could be found; there was also marked lipomatosis which involved particularly the area beneath the right ventricle. It is difficult to classify this most unusual case as either a classical dilatation of the right atrium, idiopathic or secondary, or as a cardiac lipoma or lipomatosis.