ObjectiveTo investigate the clinical features and influencing factors for new-onset atrial fibrillation (AF) early after coronary artery bypass grafting.MethodsThe clinical data of 339 patients undergoing coronary artery bypass grafting in our hospital from January 2012 to January 2019 were retrospectively analyzed. There were 267 males and 72 females with an average age of 37-83 (58.03±8.90) years. The clinical features and influencing factors for new-onset AF after surgery were investigated.ResultsThere were 234 patients of off-pump coronary artery bypass grafting (OPCABG), with 36 (15.4%) new-onset AF patients after operation, among whom 16.1% were males and 12.5% were females. There were 105 patients of on-pump coronary artery bypass grafting (CABG), with 39 (37.1%) new-onset AF patients, among whom 40.7% were males and 25.0% were females. The incidence was higher after the CABG surgery than that after the OPCABG surgery (37.1% vs. 15.4%, P<0.05). There was no statistical difference in the incidence rate between males and females (P>0.05). The incidence of new-onset AF after surgery was higher in ≥60 years patients for both operations (18.9% and 45.8%), which was significantly higher than that in <45 years patients (P<0.05). For both operations, the incidence of new-onset AF after surgery was high on the second day (24-48 h) after surgery, and most of the AF lasted for 1 day (P<0.05). The hypertension (OR=4.983, P=0.036), frequent premature atrial contraction or atrial tachycardia (OR=17.682, P=0.002), postoperative creatine kinase isoenzyme MB (CKMB) (OR=0.152, P=0.042), left anterior and posterior diameters (OR=17.614, P<0.001) and preoperative ejection fraction (OR=7.094, P=0.011) were influencing factors for new-onset AF after OPCABG. Diabetes (OR=11.631, P=0.020), other cardiac malformations (OR=29.023, P=0.002), frequent premature ventricular contraction or ventricular tachycardia (OR=0.047, P=0.001), and postoperative CKMB (OR=3.672, P=0.040) were influencing factors for new-onset AF after CABG.ConclusionThe incidence of new-onset AF after CABG is higher than that after OPCABG, and it increases with age increasing. There is no difference in the incidence between males and females. The influencing factors for the two operations are different.