Predictors of postoperative atrial fibrillation after off-pump coronary artery bypass grafting – a prospective observational study

Objective: Postoperative atrial fibrillation (AF) is a common and potentially morbid complication following coronary artery bypass graft (CABG) surgery.Many factors have been suggested to increase the incidence of postoperative AF after CABG.The objective was to estimate the proportion of patients developing AF after off-pump CABG (OPCABG) and to determine the possible predictors of AF after OPCABG.Methods: This was a prospective observational study done in the Department of Cardiovascular and Thoracic Surgery in a tertiary center from January 2020 to December 2021 after obtaining Institutional Ethical committee clearance.A sample size was 364 and patients undergoing OPCABG were consecutively recruited in the study.We evaluated demographic, anthropometric, risk factors, echocardiographic, and peri-and intra-operative variables and CHA2DSSVasc score in patients included in the study.Postoperative AF was established using continuous electrocardiogram monitoring.The predictors we established using regression analysis.Results: In this prospective study amongst 364 patients recruited, 33 (9.06%) developed AF.Patients who developed AF were older in age with a mean age of 61.22 (8.28) years (p=0.037)compared to those who did not develop AF.CHA2DS2-VASc score cut-off value ≥3 was used and it predicts the development of AF in post CABG patients (OR -1.358, p=0.038).Low ejection fraction 38.22 (9.42)% (p=0.0540)(OR=0.997,p=0.053), increased left ventricular end-systolic dimension (LVESD) 34.38 (8.066) mm (p=0.002)(OR=1.032,p=0.058), increased left ventricular end-systolic dimension (LVEDD 48.35 (5.49) mm (p=0.002)(OR=1.054,p=0.025) were associated with development of AF after OPCABG.However only larger LVEDD, high CHA2DS2-VASc score and advanced age (>60 years) were significant predictors of AF in our study. Conclusion:In our study advanced age, CHA2DS2-VASc scoring system, and echocardiographic parameters like LVEF, LVEDD, and LVESD appear to be predictors of postoperative AF.Sex, body mass index, hypertension, diabetes, usage of beta-blockers, and left atrial parameters do not appear to be predictors of postoperative AF.