The efficacy and safety of botulinum toxin epicardial fat injection to prevent postoperative atrial fibrillation in patients undergoing cardiac surgery: a meta-analysis of randomized controlled trials.

[BACKGROUND] Postoperative atrial fibrillation (POAF) is prevalent in about 30% to 60% of patients undergoing cardiac surgery, leading to worse outcomes. Botulinum toxin type A (BTX) epicardial injection has been proposed to prevent POAF by impairing cholinergic signaling.

[METHODS] A systematic review and meta-analysis synthesized randomized controlled trials, which were retrieved by searching PubMed, EMBASE, Web of Science, SCOPUS, and Cochrane through November 23, 2022. RevMan version 5.4 was used to pool dichotomous outcomes using risk ratio (RR) and continuous outcomes using mean differences (MD) presented with the corresponding confidence interval (CI).

[RESULTS] Three randomized controlled trials with 509 patients (308 in the BTX group and 205 in the placebo group) were included in the analysis. There was no difference between BTX and placebo regarding POAF incidence (RR 0.81 with 95% CI [0.65, 1.00],  = 0.05), postoperative hospital length of stay in days (MD -0.03 with 95% CI [-0.54, 0.49],  = 0.91), all-cause mortality (RR 1.64 with 95% CI [0.22, 12.17],  = 0.63), any adverse event (RR 1.03 with 95% CI [0.94, 1.12],  = 0.51), or any serious adverse event (RR 0.89 with 95% CI [0.68, 1.15],  = 0.36).

[CONCLUSION] There was no difference between the epicardial fat injection of BTX versus placebo for preventing POAF.