Echocardiographic assessment of the left atrial appendage

The left atrial (LA) appendage is a common source of cardiac thrombus forma tion associated with systemic embolism. Transesophageal echocardiography al lows a detailed evaluation of the structure and function of the appendage b y two-dimensional imaging and Doppler interrogation of appendage flow. Spec ific flow patterns, reflecting appendage function, have been characterized for normal sinus rhythm and various abnormal cardiac rhythms. Appendage dys function has been associated with LA appendage spontaneous echocardiographi c contrast, thrombus formation and thromboembolism. These associations have been studied extensively in patients with atrial fibrillation or atrial fl utter, in patients undergoing cardioversion of atrial arrhythmias and in pa tients with mitral valve disease. The present review summarizes the literat ure on the echocardiographic assessment of LA appendage structure, function and dysfunction, which has become an integral part of the routine clinical transesophageal echocardiographic examination. (C) 1999 by the American Co llege of Cardiology.