Impact of left atrial appendage morphology on peri-interventional thromboembolic risk during catheter ablation of atrial fibrillation.

Background: Left atrial appendage (LAA) morphology recently has been suggested to influence thromboembolic risk in patients with atrial fibrillation (AF).

Objective: The purpose of this study was to examine the impact of LAA morphology on peri-interventional thromboembolic events in patients undergoing AF catheter ablation.

Methods: Of 2570 consecutive patients undergoing AF ablation, 17 patients with cerebral thromboembolic events within 30 days of AF ablation were selected and matched for CHA2DS2VASc score, peri-interventional anticoagulation, and procedural characteristics with 68 event-free patients. LAA morphology was visualized by cardiac computed tomography and classified into 4 types: cactus, chicken wing, windsock, and cauliflower.

Results: Baseline, echocardiographic, and procedural characteristics of both patient groups were similar. Patients with embolic complications had a significantly higher incidence of chicken wing morphology compared to event-free controls (65% vs. 21% chicken wing, 18% vs. 24% cactus, 12% vs. 13% windsock, 5% vs. 42% cauliflower, respectively, P < .001), which translates into a >7× higher risk compared to other morphologies (odds ratio 7.2, 95% confidence interval 1.353-38.328, P = .021) when adjusted for possible confounders associated with chicken wing morphology.

Conclusions: LAA chicken wing morphology is associated with higher periprocedural thromboembolic risk in patients undergoing AF ablation. Further studies are needed to determine the mechanisms and possible implications of this observation.