Efficacy and safety of various antithrombotic regimens after left atrial appendage occlusion

Aim . To evaluate the efficacy and safety of various antithrombotic regimens after left atrial appendage occlusion (LAAO) in real clinical practice. Material and methods . This prospective observational study included 90 patients with nonvalvular atrial fibrillation and a high risk of ischemic stroke/systemic embolism who underwent endovascular LAAO using the Watchman device. The primary endpoint was the cumulative incidence of ischemic stroke/transient ischemic attack/systemic embolism, major and clinically relevant bleeding according to the Global Anticoagulant Registry in the Field-Atrial Fibrillation (GARFIELD) criteria, and all-cause mortality. Results . Patients were divided into subgroups depending on the antithrombotic therapy carried out after LAAO: 1) direct oral anticoagulants (DOACs) ± antiplatelet agents; 2) warfarin ± antiplatelet agents; 3) dual antiplatelet therapy (aspirin + clopidogrel). Multivariate analysis showed a trend toward a lower incidence of the primary endpoint in the DOAC group compared with both warfarin (hazard ratio, 8,49; 95% confidence interval: 2,0-36,15; p=0,004) and antiplatelet agents (hazard ratio, 4,34; 95% confidence interval: 1,08-17,36; p=0,038). At the same time, there were no significant differences in the prevalence of primary endpoint between the warfarin and antiplatelet groups. There was no relationship between device-related thrombosis and postoperative antithrombotic regimen. Conclusion . Endovascular LAAO is an effective and safe alternative to anticoagulant therapy. The present real-world evidence study revealed that the administration of DOACs after LAAO is associated with a greater efficacy and safety profile compared to warfarin and dual antiplatelet therapy.