LAA Occlusion During Surgery Reduces Stroke Risk in Patients With Atrial Fibrillation

A surgeon performs coronary artery bypass grafting open heart surgery artery
Left atrial appendage occlusion reduced stroke risk in patients with atrial fibrillation undergoing cardiac surgery.

The risk of ischemic stroke or systemic embolism was lower in patients with atrial fibrillation who had left atrial appendage occlusion during cardiac surgery compared with patients who did not, authors of a multicenter randomized trial published in the New England Journal of Medicine report.

Notably, surgical occlusion of the left atrial appendage can be performed during cardiac surgery undertaken for other reasons, according to the authors, who wrote that while the procedure has been hypothesized to prevent ischemic stroke in patients with atrial fibrillation, this has not been proved.

The investigators enrolled adult participants in the Left Atrial Appendage Occlusion Study III (LAAOS III; Identifier: NCT01561651) who had a history of atrial fibrillation and a CHA2DS2-VASc score of at least 2 (on a scale of 0 to 9, with higher scores indicating greater risk) and were scheduled to undergo cardiac surgery for another indication.

Participants were randomized 1:1 to undergo or not undergo left atrial appendage occlusion during surgery. All participants were expected to receive usual care, and most received oral anticoagulation therapy during follow-up, which was at 30 days and then every 6 months after the procedure, with the final visit occurring on January 28, 2021. The main outcome was the occurrence of ischemic stroke (including transient ischemic attack with positive neuroimaging) or systemic embolism.

There were 2379 participants in the occlusion group and 2391 in the no-occlusion group. The mean age was 71 years, 67.5% of participants were men, and the mean CHA2DS2-VASc score was 4.2. Investigators followed 97.9% of participants for a mean of 3.8 years. In the occlusion group, 4.8% had stroke or systemic embolism vs 7.0% in the no-occlusion group (hazard ratio [HR], 0.67; 95% CI, 0.53-0.85; P =.001). The incidence of perioperative bleeding, heart failure, and death did not differ significantly between the groups.

The LAAOS III trial did not compare the effectiveness of left atrial appendage occlusion vs anticoagulation for reducing stroke risk, and “therefore does not support concomitant surgical occlusion as a replacement for oral anticoagulation,” the authors emphasized.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Whitlock RP, Belley-Cote EP, Paparella D, et al, for the LAAOS III Investigators. Left atrial appendage occlusion during cardiac surgery to prevent stroke. N Engl J Med. 2021;384(22):2081-2091. doi:10.1056/NEJMoa2101897

This article originally appeared on The Cardiology Advisor