Efficacy and Safety of Left Atrial Appendage Occlusion during Cardiac Surgery to Prevent Stroke: A Systematic Review and Meta-analysis

Abstract

Introduction: Stroke remains a major cause of morbidity and mortality after cardiac surgery. One factor associated with stroke occurrence is postoperative AF (pAF), which predisposes to the formation of atrial thrombus. As most thrombi form in the left atrial appendage (LAA), there is significant interest in LAA as a potential therapeutic target. While guidelines recommend direct oral anticoagulants (DOACs) as the preferred therapy for stroke prevention in patients with AF and a CHA2DS2-VASc score of ≥2, they cannot be administered to all patients who are poor candidates for long-term oral anticoagulation because of the high risk of bleeding, drug compliance and drug tolerance. There are limited data on the efficacy and safety of LAA occlusion (LAAO) during cardiac surgery for stroke prevention. Methods: A comprehensive and relevant search of randomised controlled trials, cohort and case–control studies was conducted. Outcome measures for ischaemic stroke events, all-cause mortality and pAF were extracted and analysed using a random-effects model. Results: Twelve studies were included and 18,982 subjects were analysed. There were 231 ischaemic stroke events in 9,473 patients who received LAAO compared with 371 ischaemic stroke events in 9,509 patients who did not receive LAAO. Concomitant LAAO showed a significant difference in ischaemic event rate (risk ratio [RR] 0.65; [95% CI: 0.55–0.77]; p<0.00001, I2=0%) and all-cause mortality (RR 0.74; 95% CI [0.57–0.97]; p=0.03; I2=68%). For pAF, there was no difference between the two groups (RR 1.08; 95% CI [0.95–1.22]; p=0.24; I2=72). Conclusion: Concomitant LAAO was more effective in preventing ischaemic stroke events and all-cause mortality, with an overall moderate certainty of evidence. However, pAF rates were similar between LAAO and non-LAAO groups.