Comparison of clinical outcomes between multiple antithrombotic therapy versus left atrial appendage occlusion with dual antiplatelet therapy in patients with atrial fibrillation undergoing drug-eluting stent implantation

Abstract

Background Complex antithrombotic regimens are recommended for patients with atrial fibrillation (AF) undergoing drug-eluting stent (DES) implantation but carry high bleeding risk. Hypothesis We aimed to evaluate whether left atrial appendage occlusion (LAAO) with dual antiplatelet therapy (DAPT) improve clinical outcomes when compared with multiple antithrombotic therapy (MAT) in patients with AF undergoing DES implantation. Methods Among 475 AF patients who underwent DES, 41 patients treated by LAAO with DAPT and 434 patients on MAT were compared. MAT was defined as any combination of warfarin-based antithrombotic therapy. Among the MAT group, 34.8% were on triple antithrombotic therapy. The primary endpoint was a net adverse clinical event (NACE), a composite of cerebrovascular accident (CVA) and major bleeding. Secondary endpoints were CVA, major bleeding, major adverse cardiac and cerebral event (MACCE), MI, cardiovascular death, and all-cause death. Additional analysis between the new oral anticoagulant (NOAC)-based antithrombotic therapy group (n = 45) and the LAAO group was performed for the same endpoints. To adjust the confounding factors, inverse probability of treatment weighting (IPTW) was applied during the endpoint analysis. Results The LAAO group showed higher incidences of diabetes mellitus, prior CVA, higher CHA2DS2-VASc score (4.56±1.55 vs. 2.96±1.60; P<0.0001), and higher HAS-BLED score (3.24±1.20 vs. 2.13±0.75; P<0.0001). NACE occurred less frequently in the LAAO group than the MAT group at 24 months (9.4% vs. 15.3%; hazard ratio 0.274; 95% confidence interval 0.136 – 0.553; P = 0.0003), mainly driven by the reduction in major bleeding (2.4% vs. 9.3%; hazard ratio 0.119; 95% confidence interval 0.032 – 0.438; P = 0.001). The LAAO group with greater thrombotic and hemorrhagic risks showed comparable primary/secondary outcomes with the NOAC-based anti-thrombotic therapy group. Conclusions Among patients with AF who underwent DES implantation, the LAAO group had better net clinical outcomes for preventing CVA and major bleeding than the MAT group. Further large-scale trials including comparisons with NOACs are warranted.