Comparison of clinical outcomes of dual versus single antiplatelet therapy after left atrial appendage occlusion in patients with high bleeding risk or contraindications for oral anticoagulant：a study-level Meta-analysis

AIM To the optimal antiplatelet strategy after left atrial appendage closure （LAAC） in patients with high bleeding risk or absolute contraindications for oral anticoagulant is unclear. This study aims to compare DAPT with SAPT for efficacy and safety in patients undergoing LAAC.

METHODS  A database search was conducted using PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov for trials that compared DAPT with SAPT after LAAC. The outcomes included ischemic stroke （IS）, major bleeding and device-related thrombus （DRT）. We included 18 nonrandomized clinical trials with 3637 patients, of whom 2479 patients received DAPT, while 1158 patients received SAPT.

RESULTS  The DAPT group had lower IS than the SAPT group （2.5% vs.3.3%, OR: 0.75, 95% CI: 0.40～1.42, P=0.380, I²=0%）, the difference was not statistically significant. There was no significant difference about major bleeding between groups （5.4% vs.4.3%, OR: 0.91, 95% CI: 0.46～1.79, P=0.790, I²=52%）. When Vagnali-203 was excluded, major bleeding was significantly higher (P<0.05)in the DAPT group than SAPT group （6.5% vs.2.3%, OR: 2.64, 95% CI: 1.23～5.68, P=0.010, I²=0%） in high-quality study subgroup. DRT was comparable between two groups （2.5% vs.2.7%, OR: 0.68, 95% CI: 0.42～1.12, P=0.130, I²=0%）.

CONCLUSIONS  In patients who underwent LAA occlusion, post-procedural use of SAPT instead of DAPT is associated with a trend of major bleeding reduction, with no significant increase in the risk of thrombotic events.