Premature atrial contraction as a predictor of postoperative atrial fibrillation.

Abstract

Postoperative atrial fibrillation occurs in 20%-60% of patients after cardiac surgery. Recently, premature atrial contraction has been considered an initiator of atrial fibrillation. This study evaluated whether the frequency of premature atrial contractions predicts the occurrence of postoperative atrial fibrillation. The subjects of this study were 70 patients with no history of atrial fibrillation who had undergone a 24-h Holter electrocardiogram before off-pump coronary artery bypass. Their records were reviewed and postoperative electrocardiograms and telemetry strips were analyzed for postoperative atrial fibrillation. Postoperative atrial fibrillation was documented in 22 (31.4%) patients. The frequency of preoperative premature atrial contractions was significantly higher in the postoperative atrial fibrillation group (4128 ± 7186 vs. 69 ± 221 beats/24 h, p < 0.001). The incidence of postoperative atrial fibrillation increased with the frequency of preoperative premature atrial contractions which occurred in 60% of patients in the upper 50th percentile group of preoperative premature atrial contractions. Multivariate logistic regression analysis revealed the upper 50th percentile group of preoperative premature atrial contractions (odds ratio = 67; 95% confidence interval: 5.51-838; p = 0.001) to be an independent predictor of postoperative atrial fibrillation. A high frequency of preoperative premature atrial contractions is a strong independent predictor of postoperative atrial fibrillation in off-pump coronary artery bypass.