Abstract 15076: Long-Term Recurrence Free Survival in Second Generation Cryoballoon Ablation for Persistent Atrial Fibrillation: It’s All About the Autonomic Nervous System

Abstract

Introduction: Cryoballon (CB)-guided pulmonary vein isolation (PVI) is an accepted treatment option for atrial fibrillation (AF). The cardiac autonomic nervous system (ANS) plays a crucial role in the regulation of AF. Hypothesis: ANS modulation has an impact on patients’ AF free survival following CB-ablation. The aim of this observational clinical trial was to analyze the impact of vagal reactions (VRs), as a surrogate parameter for ANS modulation, on the long-term outcome of CB-ablation in patients with persistent AF (PERS AF). Methods: Data from consecutive PERS AF patients treated with a CB-guided PVI for symptomatic drug refractory AF between 2013-2023 were analyzed. VRs were defined as bradycardia < 40 beats/min, asystole or higher-degree atrioventricular block. All patients were continuously followed up in our outpatient clinic. AF-recurrence was defined as AF lasting > 30 seconds beyond a 3-month blanking period. Results: A total of 250 consecutive patients (mean age 63.9 ± 10.0 years, 70% male) were included. VRs were recorded in 61 patients (24%). The mean follow-up duration amounted to 84±14 months. Within this observation period 101 patients (40%) developed AF recurrence a mean of 1.75 ± 0.80 times. Re-ablation procedures were performed in 61 patients (60%) a mean of 1.28 ± 0.55 times. Reconnected PVs were documented in 41 cases (67%). An additional substrate modification was performed in 34 procedures (42%). Patients with procedure associated VRs presented with a significantly higher estimated AF-free survival rate compared to those without (log-rank p-value=0.016) (Figure1). Multivariate analyses revealed the days to first AF recurrence following primary CB-ablation as an independent predictor for AF-free survival (CI 0.841-0.928, HR, 0.883, p<0.01). Conclusions: CB-ablation procedure associated VRs seem to be associated with a favorable long-term outcome in PERS AF. Thus, our findings may influence future CB-ablation strategies.