Analysis of the postoperative epicardial auriculogram after surgical ablation of atrial fibrillation: Risk stratification of late recurrences

Abstract

Objectives Late recurrence of atrial fibrillation frequently occurs after atrial ablation. Risk stratification for success and recurrence of the antiarrhythmic surgical procedure has not yet been established. We studied postoperative epicardial unipolar auriculograms to distinguish between high- and low-risk patients with late recurrence of atrial fibrillation. Methods Epicardial atrial fibrillatory activity was registered in 70 patients with surgical ablation of permanent atrial fibrillation and postoperative recurrence through the temporary wires. The atrial activation pattern was characterized in 3 groups (type I, II, and III) using Wells’s criteria. The groups were homogeneous in the main clinical preoperative and surgical variables. Results Mean atrial frequency of postoperative atrial fibrillation recurrence showed differences between groups: 225 ± 53 ms in type I, 177 ± 21 ms in type II, and 150 ± 19 ms in type III (P < .01). At the end of the study, sinus rhythm was achieved in 80% of the subjects with type I, 87.5% with type II, and 23.8% with type III (P < .001). During follow-up, late atrial fibrillation recurred in 21.7% of patients with type I, 17.4% with type II, and 64.2% with auriculogram type III. In multivariate regression analysis, the postoperative auriculogram type III was the only predictor of late atrial fibrillation recurrence (odds ratio 15.6; 95% confidence interval, 3.2–74.7; P < .001). Conclusions The unipolar epicardial auriculogram was able to characterize the complexity of the postoperative fibrillatory process and also to identify patients with a high risk of late recurrence. Auriculogram type III had a low success rate for the intraoperative ablation procedure. The lines of the ablation procedure facilitated organization of the auriculograms.