Transesophageal echocardiographic diagnosis of thrombus in accessory lobes of the left atrial appendage.

Fifty-four percent of left atrial appendages have two lobes. The number ranges from one to four lobes. We describe three patients with accessory lobes of the left atrial appendage studied with multiplanar transesophageal echocardiography (TEE). In one patient there was evidence of thrombi in the accessory lobe.