Atrial fibrillation after cardiac surgery-A systematic review and meta-analysis

Background: New onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. The POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known.Objective: To perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in cardiac surgery.Methods: A systematic review and a meta-analysis of studies presenting outcomes for cardiac surgery based on the presence or absence of POAF was performed. The MEDLINE, EMBASE and Cochrane Library were assessed and 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. The statistical methods of inverse variance and a random model were performed.Results: The POAF was associated with perioperative mortality (odds ratio, OR = 1.92, 95% confidence interval, CI 1.58; 2.33), perioperative stroke (OR = 2.17, 95% CI 1.90; 2.49), perioperative myocardial infarction (OR = 1.28, 95% CI 1.06; 1.54), perioperative acute renal failure (OR = 2.74, 95% CI 2.42; 3.11), hospital (standardized mean difference, SMD = 0.80, 95% CI 0.53; 1.07) and ICU stay (SMD= 0.55, 95% CI 0.24; 0.86), long-term mortality (incidence rate ratio, IRR= 1.54, 95% CI 1.40; 1.69), long-term stroke (IRR= 1.33, 95% CI 1,21;1,46) and chronic atrial fibrillation (IRR= 4.73, 95% CI 3.36; 6.66).Conclusion: The results suggest that POAF in cardiac surgery is associated with an increased occurrence of most short-term and long-term cardiovascular adverse events; however, the causality of this association remains to be established.