Impact of atrial fibrillation termination site and termination mode in catheter ablation on arrhythmia recurrence.

BACKGROUND Although atrial fibrillation (AF) termination has been reported as a predictor of clinical outcome after persistent AF (PsAF) ablation, the relationship between AF termination site and mode and clinical outcome has not been fully evaluated. METHODS AND RESULTS A total of 135 patients (62±9 years) underwent their first ablation procedure for PsAF (76 longstanding PsAF). With an endpoint of AF termination, the ablation procedure was performed sequentially in the following order: pulmonary vein (PV) antrum isolation, and left atrial and right atrial substrate modification. AF termination was achieved in 69 patients (51%; 24 at the PV antrum, and 45 in the atrium; direct conversion to sinus rhythm in 21, and atrial tachycardia [AT] in 48). With a mean of 1.7±0.7 procedures/patient, 100 patients (74%) were free from atrial tachyarrhythmia (ATa) during a median of 15.0 months of follow-up. During the initial procedure, the AF termination site (atrium vs. PV antrum, hazard ratio [HR], 1.38; 95% confidence interval [CI]: 0.72-3.77; no termination vs. PV antrum, HR, 2.32; 95% CI: 1.26-6.30; P=0.023) and mode (AT vs. sinus rhythm, HR, 1.47; 95% CI: 0.77-4.01; no termination vs. sinus rhythm, HR, 2.38; 95% CI: 1.26-6.46; P=0.017) were independent predictors of ATa recurrence after the last ablation procedure. CONCLUSIONS The site and mode of AF termination during the index ablation procedure predict ATa recurrence following multiple catheter ablation procedures for PsAF.