LAAOS III: Does LAAO During Cardiac Surgery Reduce Risk of Stroke in AFib Patients?

The incidence of ischemic stroke or systemic embolism following cardiac surgery was lower in patients with atrial fibrillation (AFib) and a high risk of stroke who had left atrial appendage occlusion (LAAO) performed at the same time as heart surgery, said researchers presenting findings from the LAAOS III trial May 15 during ACC.21. The findings were also published in the New England Journal of Medicine.

Researchers enrolled 4,811 patients undergoing cardiac surgery at 105 centers in 27 countries. About two-thirds of the trial participants underwent valve surgery and 20% underwent coronary artery bypass graft surgery. All the patients had documented AFib or atrial flutter and a CHA₂DS₂-VASc score ≥2, indicating an elevated risk of stroke. Half of the participants were randomly assigned to receive LAAO at the time of their heart surgery. All patients received standard anticoagulant medications after surgery.

After a median follow-up of 3.8 years, LAAO lowered the risk of stroke or systemic embolism, the primary endpoint, by 33% overall in patients with AFib or atrial flutter. After the first 30 days post procedure, patients who received LAAO were 42% less likely to suffer a stroke over long-term follow-up than those who did not receive LAAO. The trial was stopped early due to the strength of the observed benefits from the procedure.

The results were consistent across all subgroups analyzed, with LAAO bringing the same benefits regardless of geographic location, sex, age, type of AFib, type of blood thinner used or other variables. On average, the procedure added less than 10 minutes to the heart surgery and demonstrated safety both in the short- and long-term. Researchers noted that LAAO procedures in the study were performed through a standard surgical approach, so it is unclear whether catheter-based approaches for LAAO would bring the same benefits.

"The study confirms a new paradigm for stroke prevention for patients with atrial fibrillation," said Richard Whitlock, MD, PhD, a cardiac surgeon at McMaster University in Ontario, Canada, and the study's lead author. "The additive benefit of surgical LAAO on top of blood thinners has now been proven. There is no question that patients who are undergoing heart surgery and have elevated stroke risk and atrial fibrillation should have their atrial appendage occluded in their cardiac surgery."

In a related editorial comment, Richard L. Page, MD, FACC, wrote that LAAOS III "provides important answers, even as it raises questions." Among the questions: "whether percutaneous occlusion, when added to ongoing oral anticoagulation, might provide benefit over anticoagulation alone in high-risk patients with [AFib]."

Clinical Topics: Arrhythmias and Clinical EP, Cardiac Surgery, Congenital Heart Disease and Pediatric Cardiology, Heart Failure and Cardiomyopathies, Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Atrial Fibrillation/Supraventricular Arrhythmias, Cardiac Surgery and Arrhythmias, Cardiac Surgery and CHD and Pediatrics, Cardiac Surgery and Heart Failure, Congenital Heart Disease, CHD and Pediatrics and Arrhythmias, CHD and Pediatrics and Imaging, CHD and Pediatrics and Interventions, Acute Heart Failure, Interventions and Imaging, Interventions and Structural Heart Disease

Keywords: ACC Annual Scientific Session, ACC21, Atrial Appendage, Atrial Fibrillation, Stroke, Heart Failure, Heart Defects, Congenital, Diagnostic Imaging, Cardiac Surgical Procedures

< Back to Listings