Left atrial appendage morphology assessment for risk stratification of embolic stroke in patients with atrial fibrillation: A meta-analysis

Background Thromboembolic event (TE) risk stratification is performed by using CHA2DS2VASc score. It has been suggested that left atrial appendage (LAA) morphology independently influences TE risk in patients with nonvalvular atrial fibrillation. LAA morphology has been classified into 4 types: chicken wing, cauliflower, windsock, and cactus. Objective The purpose of this study was to determine TE risk for each LAA morphology in patients with atrial fibrillation with low to intermediate TE risk. Methods A systematic review of MEDLINE, Cochrane Library, and Embase for studies that used computed tomography, tridimensional transesophageal echocardiography, and cardiac magnetic resonance imaging to categorize the LAA morphologies with assessment of TE prevalence. Odds ratio (OR) and 95% confidence intervals (CIs) were measured using the Mantel-Haenszel method. The fixed effects model was used, and if heterogeneity (I2) was >25%, effects were analyzed using a random model. Results Eight studies with 2596 patients were included. Eighty-four percent (n=1872) of patients had a CHADS2 score of