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. (Echocardiography 2011;28:E91‐E93) Cardiac lipomas are benign rare neoplasms of the heart. They are encapsulated and well defined subendocardial or subepicardial masses that can be seen at the atrial or ventricular level. Unlike cardiac thrombus and other tumors, lipomas have low tendency to develop peripheral emboli. Although transesophageal echocardiogram (TEE) is the procedure of choice to evaluate for atrial thrombus and masses, it might be difficult to conclude a diagnosis especially in the left atrial appendage. Cardiac imaging is essential to differentiate left atrial appendage lipomas (LAAL) from other tumors and thrombi to avoid unnecessary intervention. We report the first case of LAAL found incidentally by intraoperative TEE.