Prospective Evaluation of the Utility of CHA(2)DS(2)-VASc Score in the Prediction of Postoperative Atrial Fibrillation after Off-pump Coronary Artery Bypass Surgery – An Observational Study

INTRODUCTION: Off-pump coronary artery bypass (OPCAB) surgery is associated with evasion of complications of cardiac bypass. The incidence of postoperative atrial fibrillation (POAF) may also be reduced because of less ischemia and inflammation. AIM: Prospective evaluation of utility of CHA(2)DS(2)-VASc score in the prediction of POAF after OPCAB surgery. METHODOLOGY: In this prospective, observational study, 99 patients who underwent elective isolated OPCAB surgery were included. Patients with pacemaker in situ, receiving antiarrhythmic drugs preoperatively, and preexisting atrial fibrillation were excluded. A detailed history taking and physical examination were done preoperatively and the CHA(2)DS(2)-VASc scores were calculated for each patient. They received a standard anesthetic including midazolam, fentanyl, propofol, vecuronium, and isoflurane. The number of grafts, inotrope usage, and blood product transfusion in the perioperative period were noted. Patients were followed up for 5 days after surgery for development of new onset POAF requiring treatment. RESULTS: About 20 of the 99 patients developed POAF. POAF occurred most commonly on postoperative day 2. They were older, more likely diabetic, had preoperative diastolic dysfunction, and received blood products perioperatively. POAF group had higher mean CHA(2)DS(2)-VASc score (3.6 ± 0.821 vs. 2.11 ± 1.35) and had longer hospital stay (16.85 ± 8.61 vs. 12.6 ± 4.05 days) than no POAF group. The cutoff for CHA(2)DS(2)-VASc score was 3, which showed 90% sensitivity, 77.22% specificity, 50% positive predictive value, and 96.63% negative predictive value. CONCLUSIONS: CHA(2)DS(2)-VASc score is useful in predicting POAF after OPCAB surgery. Higher the CHA(2)DS(2)-VASc score, greater is the possibility of development of POAF.