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. Previous work has relied on heart rate variability (HRV), which cannot differentiate sympathetic from vagal activity. We used deceleration capacity (DC) and acceleration capacity (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 patients with PAF.

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 using Pearson correlation. Receiver operating characteristic analyses were used to evaluate the predictive value of DC/AC for atrial fibrillation (AF) recurrence. Kaplan-Meier analysis assessed freedom from AF recurrence over 12 months in relation to autonomic indices.

RESULTS

Pulmonary vein isolation 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 < .05 for both). Most HRV parameters had weak correlations with DC/AC (Pearson r = 0.08-0.67). At 12 months, the drug-free atrial tachycardia-free rate was 75.56%. Preablation DC/AC (area under the curve 0.63/0.64) and changes in DC/AC (area under the curve 0.68/0.67) were able to predict AF recurrence. Patients with lower preablation |AC| and smaller ΔDC/ΔAC had significantly higher AF recurrence rates (log-rank P < .05).

CONCLUSION

Our evaluation via DC/AC revealed significant alterations in autonomic activity after 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.