Incidental parasympathetic cardiac denervation during atrial fibrillation ablation using high power short duration: a marker of long-term success.

Background: There are multiple factors in both technique and substrate that lead to recurrence of atrial fibrillation after ablation. We sought to examine whether the degree of heart rate increase (HRI) caused by concurrent high-power-short-duration (HPSD) incidental parasympathetic denervation during AF ablation predicts long term success. Between December 2018 and December 2021, prospectively enrolled 214 patients who presented in sinus rhythm at AF ablation. Used 50 W of power and contact force (CF) of 5-15 g and 10-20 g at a flow rate of 40 mL/min on the anterior and posterior left atrial walls, respectively.

Results: Males were 143 (66.8%) and paroxysmal was 124 (57.9%) patients. Mean age 61.1 ± 12.3 years and follow-up time was 32.8 ± 13.2 months. Arrhythmia occurred after 90 days in 39 (18.2%) patients, 19 (48.7%) from the paroxysmal and 20 (51.3%) from the persistent AF patients. Recurrence group showed a lower HRI from a mean of 57 ± 7.7 to 64.4 ± 10.4 bpm (12.3%) while in success group HRI was from 53.8 ± 9.7 to 66.8 ± 11.6 bpm [(24.2%) p = 0.04]. We divided HRI in 3 percentiles of ≤ 8%, > 8 ≤ 37% and > 37%. A predictor of recurrence was identified in those in the first (< 8%, p = 0.006) and a predictor of success in the later (> 37%, p = 0.01) HRI percentile.

Conclusion: Atrial fibrillation ablation with HPSD incidental cardiac parasympathetic denervation identified that patients with lower heart rate increase are prone to recurrence while those with higher heart rate increase had higher maintenance of sinus rhythm at a long-term follow-up.