Right atrial appendage thrombosis in atrial fibrillation: Its frequency and its clinical predictors

This study assesses the incidence of right atrial (RA) chamber and appendag e thrombosis in patients with atrial fibrillation (AF) in relation to RA ap pendage morphology and function. Transthoracic and multiplane transesophage al echocardiography were performed in 102 patients with AF to assess the in cidence of RA and left atrial (LA) thrombi and spontaneous echo contrast,. Both right and left ventricular sizes, atrial chamber and appendage sizes a nd function were measured, Twenty- two patients in sinus rhythm served as t he control group (SR), Complete visualization of the RA appendage was feasi ble in 90 patients with AF. Patients with AF had lower tricuspid annular ex cursion (p = 0.008) and larger RA chamber area (p = 0.0001) than patients i n SR, In addition, RA appendage areas were larger (p <0.05) and RA ejection fraction and peak emptying velocities (both p <0.0001) were lower in patie nts with AF patients than in those in SR. Equivalent differences were found for the LA appendage. Six thrombi were Found in the RA appendage and 11 th rombi in the LA appendage in AF patients, Spontaneous echo contrast was fou nd in 57% and 66% in the right atrium and in the left atrium, respectively. AF patients with RA appendage thrombi had a larger RA area (p = 0.0001), a nd lower RA appendage ejection fraction and emptying velocities (both p = 0 .0001) than patients without thrombi, Spontaneous echo contrast was detecte d in all patients with thrombi. Spontaneous echo contrast was the only inde pendent predictor of RA (p = 0.03) and LA appendage thrombosis (p = 0.036), In conclusion, multiplane transesophageal echocardiography allows the asse ssment of RA appendage morphology and function. RA spontaneous echo contras t is the only independent predictor of RA appendage thrombosis. (C) 1999 by Excerpta Medica, Inc.