Effects of pulsed field ablation on autonomic nervous system in paroxysmal atrial fibrillation: A pilot study

Vagal responses and phrenic activation are commonly observed during pulsed field ablation (PFA). However, whether the vagal responses and phrenic activations are nerve damage or a neurological stress response due to electrical stimulation is unclear.The purpose of this study was to evaluate the effect of a PFA system for performing pulmonary vein isolation on the autonomic nervous system.Patients with paroxysmal atrial fibrillation (AF) who underwent PFA between August 2021 and November 2021 were included. Nerve injury biomarkers and heart rate variability were obtained preablation and postablation. Patients were scheduled to undergo magnetic resonance imaging and diffusion-weighted imaging to evaluate cerebral microembolus formation postablation.Acute electrical isolation was achieved in 100% of pulmonary veins (n = 72) in the 18 patients. Mean total procedural time was 64.1 ± 18.2 minutes, and mean fluoroscopy time was 12.3 ± 3.5 minutes. Serum nerve injury biomarkers did not show any changes preablation and immediately postablation and 24 hours after ablation (all P >.05). Preablation and 30-day postablation heart rate variability did not differ (all P >.05). Postablation diffusion-weighted imaging revealed no acute cerebral microembolus events. Moreover, there were no other procedure-related complications. The 8-month Kaplan-Meier estimate of freedom from arrhythmia was 83% ± 9%.PFA does not induce nerve injury during pulmonary vein isolation for paroxysmal AF.