Left atrial appendage lipoma: an unusual location of cardiac lipomas

Cardiac lipomas are benign neoplasms of the heart and accounts for 8.4% of all primary tumors. They can occur sporadically at any age with no sex preference. The tumor originates mostly in the subendocardium and subepicardium but very rarely within the myocardium. Clinically this tumor is asymptomatic and found incidentally in the vast majority of cases. On occasion large lesions can lead to mechanical obstruction and pericardial effusions if located in the epicardium. Although lipomas can occur at different atrial or ventricular locations, it was never reported at the level of the left atrial appendage (LAA). Usually a mass in the LAA represents a thrombus, however there are few case reports of LAA tumors mainly representing fibroelastomas, myxomas, hemangiomas, and malignant tumors. To our knowledge there are no reported cases of left atrial appendage lipomas (LAAL) in the medical literature. We report the first case of LAAL discovered incidentally on transesophageal echocardiogram during off pump coronary artery bypass grafting.