METHODS: We searched CENTRAL, MEDLINE, EMBASE and trial registries for randomised controlled trials that evaluated metoprolol for preventing the occurrence of POAF after surgery against other treatments or placebo. Random-effects model was used for estimating the risk ratios (RRs) and mean differences with 95% CIs.
RESULTS: Nine trials involving 1570 patients showed metoprolol reduced POAF compared with placebo (416 patients; RR 0.46, 95% CI 0.33 to 0.66; I²=21%; risk difference (RD) -0.19, 95% CI -0.28 to -0.10). However, metoprolol increased the risk of POAF compared with carvedilol (159 patients; RR 1.59, 95% CI 1.20 to 2.12; I²=4%; RD 0.13, 95% CI 0.06 to 0.20). There was no difference when compared with sotalol or amiodarone. The occurrence of cardiovascular conditions after drugs administration or death between the groups was not different. The overall quality of evidence was moderate to high. Subgroup analysis and funnel plot were not performed.
CONCLUSIONS: Metoprolol is effective in preventing POAF compared with placebo and showed no difference with class III antiarrhythmic drugs. Death and thromboembolism are associated with open heart surgery, but not significant in relation to the use of metoprolol.
PROSPERO REGISTRATION NUMBER: CRD42019131585.
METHODS AND RESULTS: The 'COlchicine for the Prevention of Perioperative Atrial Fibrillation' (COP-AF) trial is an international, blinded, randomized trial that compares colchicine to placebo in patients aged at least 55 years and undergoing major noncardiac thoracic surgery with general anesthesia. Exclusion criteria include a history of AF and a contraindication to colchicine (eg, severe renal dysfunction). Oral colchicine at a dose of 0.5 mg or matching placebo is given within 4 hours before surgery. Thereafter, patients receive colchicine 0.5 mg or placebo twice daily for a total of 10 days. The 2 independent co-primary outcomes are clinically important perioperative AF (including atrial flutter) and MINS during 14 days of follow-up. The main safety outcomes are sepsis or infection and non-infectious diarrhea. We aim to enroll 3,200 patients from approximately 40 sites across 11 countries to have at least 80% power for the independent evaluation of the 2 co-primary outcomes. The COP-AF main results are expected in 2023.
CONCLUSIONS: COP-AF is a large randomized and blinded trial designed to determine whether colchicine reduces the risk of perioperative AF or MINS in patients who have major noncardiac thoracic surgery.