Abstract 15080: Atrial Fibrillation Dilates Left Atrial Appendage Assessed by 3-dimentional Transesophageal Echocardiography
Introduction: Left atrial appendage (LAA) represents one of the major sources of cardiac thrombus formation. Atrial Fibrillation (AF) causes loss of atrial contractility and atrial dilatation. Real-time 3-dimentional transesophageal echocardiography enabled us to evaluate LAA orifice area. However, the impact of AF on LAA measurement by 3-dimentional transesophageal echocardiography remains unclear.
Hypothesis: We assessed the hypothesis that AF might dilate LAA orifice area evaluated by 3-dimentional transesophageal echocardiography and that LAA orifice area might be related to stroke events.
Methods: Between June 2013 and March 2014 real-time 3-dimentional transesophageal echocardiography of LAA was acquired in 97 consecutive subjects including 50 patients with sinus rhythm (SR), 9 AF patients with history of embolic stroke, and 38 AF patients without. The quantitative morphological analysis on LAA was performed with custom software. In advance, we excluded the patients with structural abnormality of any the valves including valvular stenosis and mitral valve prolapse, history of cardiac surgery, and congenital or pericardial heart disease.
Results: Compared with SR group, AF stroke+ and AF stroke- group had larger LAA orifice area (4.05 ± 1.55 vs. 6.26 ± 2.13 vs. 5.36 ± 1.78 cm2, ANOVA p < 0.01). LAA orifice area inversely correlated LAA flow velocity which predicts thromboembolic events (r = -0.40, p < 0.001). Moreover, in AF patients, LAA orifice area positively correlated with CHADS2 score among low- (0) , intermediate- (1) , high-risk- (≥2) categories (r = 0.34, p = 0.02).
Conclusions: AF enlarged LAA orifice area evaluated by 3-dimentional transesophageal echocardiography. In particular, it was largest in AF stroke+ patients. Indeed, the measurement of LAA orifice was useful for evaluation of stroke risk. Thus it might be a predictor of thromboembolic events in AF patients.
Author Disclosures: Y. Miki: None. S. Ichimiya: None. H. Ohishi: None. T. Aoki: None. T. Kawamiya: None. H. Ichimiya: None. Y. Uchida: None. J. Watanabe: None. M. Kanashiro: None. H. Ishii: None. T. Amano: None. T. Matsubara: None. T. Murohara: None.
- © 2014 by American Heart Association, Inc.