Insufficient evidence exists to routinely recommend surgical closure of the left atrial appendage, either surgically or with a LAA exclusion device, for patients who have atrial fibrillation, a large data review has concluded.

None of the devices so far examined is more effective than oral anticoagulation therapy in reducing AF-related stroke risk, but they appear to be riskier, with up to 1 in 15 patients experiencing a serious adverse event during or after percutaneous placement, North Noelck, MD, and his colleagues wrote (Circ Cardiovasc Qual Outcomes. 2016 Jul 12. doi: 10.1161/CIRCOUTCOMES.115.002539).

Surgical studies, which also have found no benefit, are poor in quality and provide no strong data in favor of any technique, wrote Dr. Noelck of Oregon Health and Science University, Portland.

The meta-analysis comprised 13 studies of the benefits and risks of percutaneous LAA exclusion and 7 of the benefits and harms of surgical LAA closure.

The team found “limited evidence” that one device, the Watchman (Boston Scientific), may be an effective alternative to long-term oral anticoagulation treatment in some patients. But the Watchman was also associated with “significant, procedural-related harms,” in almost 11% of patients in one large study, PROTECT-AF . These included pericardial effusions with and without associated tamponade, bleeding, device thrombus, and device embolization. However, the benefit conferred by the device appeared marginal. Neither PROTECT-AF nor the subsequent PREVAIL studies of the Watchman found that it conferred significant clinical benefit above the comparator arm of warfarin therapy. Indeed, in PREVAIL, a composite outcome of death, ischemic/hemorrhagic stroke, or systemic embolism occurred in 5.2% of the device group and in 2.9% of the warfarin group.

Three randomized studies and two observational studies examined surgical LAA closure relative to usual medical care. The authors said the randomized studies were underpowered to show clinical benefit. Neither of the observational studies showed significant advantages in stroke-free survival, but the team noted, “data such as information about anticoagulation use among the groups [were] lacking.”

“Overall, there is insufficient evidence to support the routine use of surgical LAA exclusion to reduce stroke risk or the future need for anticoagulant therapy,” wrote Dr. Noelck and his coinvestigators. However, they said, several ongoing studies “should add substantively to this body of evidence during the next several years.”

The study was funded by the Department of Veterans Affairs. None of the authors had any relevant financial disclosure.