Cardiac Deceleration/Acceleration Capacity Demonstrates Autonomic Modulation in Patients with Paroxysmal Atrial Fibrillation Undergoing Pulsed-Field Ablation

BACKGROUND: The autonomic effects of pulsed-field ablation (PFA) remain incompletely defined. Prior work has relied on heart rate variability (HRV), which cannot differentiate sympathetic from vagal activity. We employed deceleration/acceleration capacity (DC/AC)-valid vagal/sympathetic activity measures-to evaluate autonomic changes before and after PFA for paroxysmal atrial fibrillation (PAF). OBJECTIVE: The study aimed to characterize peri-PFA changes in DC/AC in PAF patients. METHODS: This prospective study included 45 consecutive patients with PAF who experienced PFA. DC/AC and HRV were performed at baseline, immediately after ablation, and at 3-month follow-up. The relationship between HRV and DC/AC was assessed by Pearson correlation. Receiver operating characteristic analyses the predictive value of DC/AC for AF recurrence. Kaplan-Meier analysis assessed freedom from AF recurrence over 12 months in relation to autonomic indices. RESULTS: Pulmonary vein isolation (PVI) was successful in all patients; 91.1% exhibited intraprocedural vagal responses. DC and |AC| decreased immediately after PFA and partially recovered at 3 months (overall P<0.05 for both). Most HRV parameters had weak correlations with DC/AC (Pearson r=0.08-0.67). At 12-month, the drug-free atrial tachycardia-free rate was 75.56%. Pre-ablation DC/AC (AUC 0.63/0.64) and changes in DC/AC (AUC 0.68/0.67) were able to predict AF recurrence. Patients with lower pre-ablation |AC| and smaller ΔDC/ΔAC had significantly higher AF recurrence rates (log-rank p<0.05). CONCLUSIONS: Our evaluation via DC/AC revealed significant alterations in autonomic activity following PFA. Furthermore, DC/AC and their trajectories demonstrated moderate predictive value for AF recurrence, underscoring the need to reconsider the impact of PFA on cardiac autonomic innervation.