Safety and efficacy of colchicine for the prevention of post-operative atrial fibrillation in patients undergoing cardiac surgery: a meta-analysis of randomized controlled trials.

BACKGROUND AND AIMS: Colchicine is an anti-inflammatory drug that may prevent post-operative atrial fibrillation (POAF). The effect of this drug has been inconsistently shown in previous clinical trials. We aimed to compare the efficacy and safety of colchicine vs. placebo to prevent POAF in patients undergoing cardiac surgery. METHODS AND RESULTS: A systematic search of EMBASE, MEDLINE, SCOPUS, ClinicalTrials.gov, and the Cochrane Library for randomized controlled trials (RCTs) was conducted from inception till April 2023. The primary outcome was the incidence of POAF after any cardiac surgery. The secondary outcome was the rate of drug discontinuation due to adverse events and adverse gastrointestinal events. Risk ratios (RR) were reported using the Mantel Haenszel method. A total of eight RCTs comprising 1885 patients were included. There was a statistically significant lower risk of developing POAF with colchicine vs. placebo (RR: 0.70; 95% CI: 0.59-0.82; P < 0.01, I2 = 0%), and this effect persisted across different subgroups. There was a significantly higher risk of adverse gastrointestinal events (RR: 2.20; 95% CI: 1.38-3.51; P < 0.01, I2 = 55%) with no difference in the risk of drug discontinuation in patients receiving colchicine vs. placebo (RR: 1.33; 95% CI: 0.93-1.89; P = 0.11, I2 = 0%). CONCLUSION: This meta-analysis of eight RCTs shows that colchicine is effective at preventing POAF, with a significantly higher risk of adverse gastrointestinal events but no difference in the rate of drug discontinuation. Future studies are required to define the optimal duration and dose of colchicine for the prevention of POAF.

Antero-lateral vs. antero-posterior electrode position for cardioversion of atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Multiple randomized controlled trials (RCTs) have compared the success of antero-lateral vs. antero-posterior electrode position for cardioversion of atrial fibrillation (AF). However, due to small sample size and conflicting results of these RCTs, the optimal electrode positioning for successful cardioversion remains uncertain. METHODS: A systematic search of MEDLINE and EMBASE was conducted. Outcomes of interest included overall success of cardioversion with restoration of sinus rhythm, 1st shock success, 2nd shock success, mean shock energy required for successful cardioversion, mean number of shocks required for successful cardioversion, success of cardioversion at high energy (> 150 J) and success of cardioversion at low energy (< 150 J). Mantel-Haenszel risk ratios (RR) with 95% confidence intervals were calculated using random-effects model. RESULTS: A total of 14 RCTs comprising 2445 patients were included. There was no statistically significant difference between two cardioversion approaches in the overall success of cardioversion (RR 1.02; 95% CI [0.97-1.06]; p = 0.43), first shock success (RR 1.14; 95% CI [0.99-1.32]), second shock success (RR 1.08; 95% CI [0.94-1.23]), mean shock energy required (mean difference 6.49; 95% CI [-17.33-30.31], success at high energy > 150 J (RR 1.02; 95% CI [0.92-1.14] and success at low energy < 150 J (RR 1.09; 95% CI [0.97-1.22]). CONCLUSIONS: This meta-analysis of RCTs shows no significant difference in the success of cardioversion between antero-lateral vs. antero-posterior electrode position for cardioversion of AF. Large well-conducted and adequately powered randomized clinical trials are needed to definitively address this question.