Left Atrial Appendage Morphology as a Determinant for Stroke Risk Assessment in Atrial Fibrillation Patients: Systematic Review and Meta-Analysis.

Atrial fibrillation (AF) is a leading source of emboli that precipitate cerebrovascular accident (CVA) which is correlated with left atrial appendage (LAA) morphology. We aimed to elaborate the relationship between CVA and LAA morphology in AF patients.Medline and EMBASE databases were thoroughly searched between 2010-2018 for studies that included atrial fibrillation patients and classified them into two groups based on CVA occurrence. Four different LAA morphologies (Chicken wing CW, Cauliflower, cactus and windsock) were determined in each group by 3D TEE, MDCT or CMRI. New Castle Ottawa Scale was used to appraise the quality of included studies. The risk of CVA before cardiac ablation and/or LAA intervention in CW patients was compared to each type of non-CW morphologies. The extracted data was statistically analyzed in the form of forest plot by measuring the risk ratio (RR) using REVMAN software. P value and I square were used to assess the heterogeneity between studies.PRISMA diagram was illustrated showing 789 imported studies for screening. Three duplicates were removed, and the rest were arbitrated by 2 reviewers yielding 12 included studies with 3486 patients including 1551 with CW, 442 with cauliflower, 732 with cactus 765 with windsock. The risk of CVA in CW patients was reduced by 41% relative to non-CW patients (Total RR=0.59 (0.52-0.68)). Likewise, the risk of CVA in CW patients was less by 46%, 35% and 31% compared to cauliflower (Total RR =0.54(0.46-0.64)), cactus (Total RR =0.65(0.55-0.77)) and windsock (Total RR =0.69(0.58-0.83)) patients respectively. Low levels of heterogeneity were achieved in all comparisons (I square <35% and p value > 0.1).Patients with non-CW morphologies (cauliflower, cactus and windsock) show a higher incidence of CVA than CW patients. For that reason, LAA appendage morphology could be useful for risk stratification of CVA in AF patients.