['Atrial fibrillation (AF) is the most frequently encountered postoperative arrhythmic complication after coronary artery bypass grafting (CABG). The purpose of the present study was to investigate the incidence and predictors of postoperative AF in patients with stable and unstable angina pectoris undergoing on-pump and off-pump CABG procedures.', 'One hundred and seventeen stable, unstable on-pump and off-pump CABG patients were included in the present study. Holter data were collected 1 day before the operation to the 2nd postoperative day. AF was registered as positive if any AF event occurred.', 'The overall incidence of postoperative AF and sustained AF was 31.6 and 25.6%, respectively. Postoperative AF incidences in stable on-pump, unstable on-pump and stable off-pump patients were 29.5, 39.0 and 25%, respectively (p = 0.412). Patients with AF had compromised postoperative haemodynamic function, greater need of inotropic support and antiarrhythmic medication, and longer intensive care unit (ICU) stays.'] Is recent unstable angina and off-pump coronary artery bypass grafting related to postoperative atrial fibrillation?