Predicting risk of embolization during anticoagulation for left atrial thrombus by transesophageal echocardiography: a case report.

: A 75-year-old woman was admitted with transient left hemiparesis accompanied by diminished level of consciousness in September 1994. Holter electrocardiography showed transient atrial fibrillation, and transesophageal echocardiography (TEE) revealed an atrial septal aneurysm, spontaneous echo contrast, and a thrombus in the left atrial appendage. The patient received anticoagulant treatment with warfarin, and follow-up TEE showed thrombus resolution. However, after the warfarin was discontinued, symptoms recurred in October 1995 and TEE showed a club-like left atrial thrombus (21 x 40 mm) originating in the left atrial appendage and extending to the center of the left atrium. Follow-up TEE after warfarin therapy showed resolution at the neck of the thrombus but the head threatened detachment. The thrombus was subsequently excised surgically. Follow-up TEE was critical for detecting the risk of significant embolization during anticoagulant therapy.