Related Experiment Video
Updated: Jul 16, 2025
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Oral Anticoagulation Use and Left Atrial Appendage Occlusion in LAAOS III
Stuart J Connolly1, Jeff S Healey1, Emilie P Belley-Cote1
1Population Health Research Institute, Hamilton Health Sciences, McMaster University, Ontario, Canada (S.J.C., J.S.H., E.P.B.-C., K. Balasubramanian, K. Brady, P.J.D., M.S., C.R., S.Y., R.P.W.).
Insights
Left atrial appendage (LAA) occlusion effectively reduces stroke risk in atrial fibrillation patients undergoing cardiac surgery. This benefit is consistent regardless of whether patients use oral anticoagulant (OAC) therapy.
Area of Science:
- Cardiology
- Vascular Surgery
- Thrombosis Research
Background:
- Left atrial appendage (LAA) occlusion is proven to reduce stroke risk in atrial fibrillation patients during cardiac surgery.
- Variations in oral anticoagulant (OAC) therapy use may influence the effectiveness of LAA occlusion.
Purpose of the Study:
- To examine the impact of LAA occlusion on stroke risk reduction in relation to OAC therapy use.
- To determine if LAA occlusion's benefits are independent of OAC use.
Main Methods:
- Utilized data from the LAAOS III trial, collecting OAC use information at follow-up visits.
- Employed adjusted proportional hazards modeling with time-dependent covariates to analyze stroke risk.
- Evaluated stroke risk at multiple time points post-randomization.
Main Results:
- LAA occlusion demonstrated consistent stroke risk reduction across patient groups with varying OAC use (HRs ranging from 0.63 to 0.76).
- Analysis using OAC use as a time-dependent covariate indicated similar stroke reduction with LAA occlusion, irrespective of OAC status.
Conclusions:
- The thromboembolic risk reduction benefit of LAA occlusion is consistent, regardless of concurrent OAC therapy.
- LAA occlusion offers a valuable stroke prevention strategy for atrial fibrillation patients independent of their OAC use.
Background:
LAAOS III (Left Atrial Appendage Occlusion Study III) showed that left atrial appendage (LAA) occlusion reduces the risk of ischemic stroke or systemic embolism in patients with atrial fibrillation undergoing cardiac surgery. This article examines the effect of LAA occlusion on stroke reduction according to variation in the use of oral anticoagulant (OAC) therapy.
Methods:
Information regarding OAC use was collected at every follow-up visit. Adjusted proportional hazards modeling, including using landmarks of hospital discharge, 1 and 2 years after randomization, evaluated the effect of LAA occlusion on the risk of ischemic stroke or systemic embolism, according to OAC use. Adjusted proportional hazard modeling, with OAC use as a time-dependent covariate, was also performed to assess the effect of LAA occlusion, according to OAC use throughout the study.
Results:
At hospital discharge, 3027 patients (63.5%) were receiving a vitamin K antagonist, and 879 (18.5%) were receiving a non-vitamin K antagonist oral anticoagulant (direct OAC), with no difference in OAC use between treatment arms. There were 2887 (60.5%) patients who received OACs at all follow-up visits, 1401 (29.4%) who received OAC at some visits, and 472 (9.9%) who never received OACs. The effect of LAA occlusion on the risk of ischemic stroke or systemic embolism was consistent after discharge across all 3 groups: hazard ratios of 0.70 (95% CI, 0.51-0.96), 0.63 (95% CI, 0.43-0.94), and 0.76 (95% CI, 0.32-1.79), respectively. An adjusted proportional hazards model with OAC use as a time-dependent covariate showed that the reduction in stroke or systemic embolism with LAA occlusion was similar whether patients were receiving OACs or not.
Conclusions:
The benefit of LAA occlusion was consistent whether patients were receiving OACs or not. LAA occlusion provides thromboembolism reduction in patients independent of OAC use.
More Related Videos
Related Concept Videos
01:24Cardiac Catheterization III: Left Heart Catheterization
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
01:29Venous Thrombosis III: Interprofessional Care
01:16Local Anesthetics: Clinical Application as Intravenous Regional Anesthesia
One of the advantages of...
01:25Aortic Regurgitation III: Medical Management
01:18Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...