Predictors of Postoperative Atrial Fibrillation after Coronary Artery Bypass Grafting: A Prospective Cohort Study

Abstract Background Postoperative atrial fibrillation (POAF) is common both after cardiothoracic and non cardiothoracic surgery.In patients undergoing cardiothoracic surgery, the incidence of 16–46% has been reported. Even though POAF can be selflimiting, it may be associated with hemodynamic instability, postoperative stroke, myocardial infarction, ventricular arrhythmias and heart failure. Objective To determine the effect of certain predictors on the incidence of postoperative atrial fibrillation during the ICU stay after coronary artery bypass graft surgery. Patients and Methods This prospective cohort study was done after approval of the Institutional Review Board and written informed consent from patients or first kin. Patients undergoing isolated CABG or CABG with valve replacement were included and monitored for POAF during their postoperative ICU stay and the potential predictors of POAF as age, sex, smoking and left atrial diameter, serum Potassium and Magnesium levels, CHA2DS2-VASc score, valve replacement and inotropic support were recorded. Results 123 patients were included in the study, 76.4% were males with a mean age of 57.4 ±8.7 years and mean left atrial diameter 4.1 ±0.52 cm. The incidence of POAF following CABG surgery was almost 33.3%. There was no statistically significant association between POAF and smoking (P = 0.123). However there were statistically significant associations between POAF and CHA2DS2-VASc score, valve replacement (P 0.05). Conclusion There are a wide range of significant epidemiological, clinical, and operative predictors for the development of post-CABG AF including older age, female gender, large LA diameter, higher CHA2DS2-VASc score, valve replacement and postoperative inotropic support. Nevertheless, further large-scale studies are still needed to confirm our findings.