Left atrial appendage (LAA) closure at the time of cardiac surgery was associated with reduced intermediate-term thromboembolic risk for patients with atrial fibrillation (Afib), according to a registry study.
A retrospective analysis of the Society of Thoracic Surgeons Adult Cardiac Surgery Database showed that out of more than 10,000 patients, 37% got surgical LAA occlusion during cardiac surgery (coronary artery bypass grafting [CABG], mitral valve surgery with or without CABG, or aortic valve surgery with or without CABG).
Readmissions for stroke, transient ischemic attack, or systemic embolism reached a rate of 4.2% among those who got surgical LAA occlusion and 6.2% for those who didn’t (adjusted HR 0.67, 95% CI 0.56-0.81), J. Matthew Brennan, MD, MPH, of Duke University School of Medicine in Durham, N.C., and colleagues reported online in the Journal of the American Medical Association.
“These findings support the use of surgical LAA occlusion, but randomized trials are necessary to provide definitive evidence,” Brennan’s group concluded.
Concomitant surgical LAA occlusion was also favored by the endpoints of of all-cause mortality (17.3% versus 23.9%, adjusted HR 0.88, 95% CI 0.79-0.97) and combined thromboembolism, hemorrhagic stroke, and all-cause mortality (20.5% versus 28.7%, adjusted HR 0.83, 95% CI 0.76-0.91). Hemorrhagic strokes occurred in 0.9% of patients in both groups (adjusted HR 0.84, 95% CI 0.53-1.32).
The study included patients age 65 years and older with Medicare claims data (median age 76 years, 39% women) who had Afib. Participants were followed up to 3 years.
Surgical LAA occlusion was associated with reduced risk of thromboembolism among patients discharged without anticoagulation (4.2% versus 6.0%, adjusted HR 0.26, 95% CI 0.17-0.40), but not those discharged with anticoagulation (4.1% versus 6.3%, adjusted HR 0.88, 95% CI 0.56-1.39).
More of the surgical LAA occlusion group got anticoagulation (68.9% versus 60.3%, P<0.001).
“In the cohort of patients discharged with oral anticoagulation, surgical LAA occlusion was not associated with thromboembolism but was associated with a lower risk for hemorrhagic stroke, presumably related to eventual discontinuation of oral anticoagulation among surgical LAA occlusion patients,” the investigators noted.
An accompanying opinion article by Victor Ferraris, MD, PhD, of the University of Kentucky in Lexington, said there are important clinical implications to the study’s findings.
“A reasonable hypothesis based on the authors’ findings is that ablation procedures that occlude the left atrial appendage are adequate treatments to avoid thromboembolism and to minimize postoperative anticoagulation-related hemorrhage. This somewhat novel hypothesis, if true, could avoid a significant morbidity associated with anticoagulation while providing adequate treatment for thromboembolic complications of Afib,” Ferraris said.
Even so, the true long-term rate of anticoagulation in the study population was unknown, he noted. “The database only allowed recognition of the anticoagulation rate at discharge and did not account for subsequent use of or adherence to anticoagulation later after discharge.”
Other caveats include the limited generalizability of the study to younger individuals and the lack of stratification by surgical technique. The retrospective nature of the study also left room for residual confounding, Brennan and colleagues acknowledged.
“Any future randomized trial would have to measure the effectiveness of left atrial appendage occlusion at various times after operation and this necessity adds to the complexity of any future trial design,” according to Ferraris. “Limited data on the effectiveness of surgical LAA occlusion caused some uncertainty among professional organizations developing practice recommendations, and this uncertainty is reflected in the class IIb recommendation regarding benefit of surgical LAA occlusion for thromboembolism protection in both the U.S. and European guidelines.”
Brennan disclosed an award from the Burroughs Welcome Fund and an FDA grant.
Study co-authors reported several ties to industry.
Ferraris listed no relevant conflicts of interest.