B-PO02-151 EFFECT OF ATRIAL FIBRILLATION ABLATION ON QTC DURATION AND ASSOCIATION OF POST ABLATION QTC DURATION WITH ATRIAL FIBRILLATION RECURRENCE

Abstract

Wide area pulmonary vein isolation (PVI) has been demonstrated to effect autonomic modulation primarily by involving ganglionic plexi around the pulmonary veins/atrial junctions. Autonomic modulation has been demonstrated to reduce atrial fibrillation (AF) recurrence after ablation. We postulated the autonomic effects of PVI ablation would be reflected on QTc duration. Determine the effect of AF ablation on QTc duration and the association of post-ablation QTc duration with AF recurrence. A retrospective review identified 872 patients who had received AF ablation over 5 years. The QTc duration on ECG was determined pre-procedure, immediately post-procedure, and at six weeks follow up by two physicians. The hazard ratio of AF recurrence associated with pre-procedure QTc duration and immediate post-procedure QTc were estimated using the Cox proportional hazard model. Additionally, a direct adjusted survival curve using the Cox model was performed to determine the association of immediate post-procedure QTc duration with time to AF recurrence. AF ablation is associated with increase in mean QTc duration from 438 ± 35.6 msec to 463 ± 34.2 msec (p < 0.0001). At 6 week follow up, the mean QTc duration was 436 ± 35.4 msec. Immediate post-procedure QTc duration of 464 msec or greater was associated with lower AF recurrence (HR 0.76, 95% CI 0.59-0.98, p = 0.03). There was no difference in anesthesia related/QTc prolonging medications between the two groups. Age, female gender, persistent AF, LA size greater than 5.2 cm, OSA, and immediate post-procedure QTc duration of less than 464 msec were all independently associated with AF recurrence after ablation. Adjusted survival curves demonstrated that immediate post-procedure QTc duration of less than 464 msec was independently associated with earlier time to AF recurrence after ablation (Wald test p = 0.03). AF ablation is associated with an increase in the immediate post procedure QTc wave duration. Immediate post-procedure QTc duration of less than 464 msec was associated with earlier time to AF recurrence after ablation. Post procedure QTc is a readily available and may suggest autonomic modulation associated with AF ablation outcomes.