The impact of preoperative left atrial appendage thrombus on surgical outcomes in atrial fibrillation patients undergoing epicardial left atrial appendage closure

Background The presence of a left atrial appendage (LAA) thrombus is traditionally considered a contraindication to epicardial left atrial appendage closure (LAAC) because of the risk of periprocedural embolization. This presents a significant challenge for atrial fibrillation (AF) patients with a high bleeding risk who are intolerant to long-term anticoagulant treatment. The safety and outcomes of epicardial LAAC in patients with a preexisting LAA thrombus remain poorly defined. Methods This retrospective cohort study included 108 AF patients who underwent epicardial LAAC at a single center. Patients were stratified into two groups on the basis of preoperative imaging: the Thrombus Group ( n = 11) and the No-Thrombus Group ( n = 97). Intraoperative management, perioperative complications, and long-term clinical outcomes (cerebrovascular events and all-cause mortality) were compared between the groups. An imaging-based classification of thrombus morphology (Types I-III) was proposed for risk stratification. Results No intraoperative strokes or deaths occurred in either group. Early postoperative complication rates were low and not significantly different between groups. During follow-up, the rates of thromboembolic events (1.0 vs. 2.3 per 100 patient-years) and all-cause mortality (0.3 vs. 0.0 per 100 patient-years) were comparable between the No-Thrombus and Thrombus groups, with no statistically significant differences. Thrombi confined to the LAA tip (Type I) were associated with favorable outcomes. Conclusion Epicardial LAAC appears to be a feasible and safe alternative for stroke prevention in some AF patients with LAA thrombi who are unsuitable for anticoagulation therapy, as it does not increase perioperative risk or compromise long-term treatment efficacy.