Characterization of acute residual pulmonary vein connections using electroanatomic mapping during pulsed-field ablation of atrial fibrillation

Abstract

Background: Single-shot pulsed-field ablation (PFA) catheters show promising safety and efficacy for achieving pulmonary vein isolation (PVI) in atrial fibrillation (AF). However, additional PFA applications are sometimes required after standard PFA delivery to achieve PVI.

Objective: This study aimed to evaluate the real-world frequency and location of acute residual pulmonary vein (PV) connections using 3-dimensional electroanatomic mapping (3D-EAM) during index PFA.

Methods: Patients undergoing index PVI with a single-shot PFA catheter and receiving postablation 3D-EAM were prospectively studied. First-pass isolation (FPI) rates and distribution of residual PV connections were assessed.

Results: A total of 535 patients from 48 international centers (89 operators) were included (paroxysmal AF 375; persistent AF 160). Mean procedure time was 75.9 ± 31.9 minutes, and mapping time was 8.4 ± 5.2 minutes. Ablation was performed with a pentaspline, variable conformation PFA catheter in 72.7% of cases and a fixed-loop PFA catheter in 27.3%. Bilateral FPI was achieved in 75.1% of patients (paroxysmal AF 77.1% vs persistent AF 70.6%; P = .126). The individual PV FPI rate was 92.7% (1834 of 1978 PVs). Excluding common PVs, residual PV connections were more frequent in superior PVs (superior 8.9% vs inferior 3.8%; P < .001), specifically in the left superior PV (10.1%). Predictors of FPI included standard 4-vein anatomy (odds ratio, 1.83; 95% confidence interval, 1.09-3.07; P = .021) and the pentaspline catheter (odds ratio, 3.53; 95% confidence interval, 1.81-6.87; P < .001).

Conclusion: Using 3D-EAM, an acute residual connection of at least 1 PV was observed in a quarter of patients after standard PFA delivery and was most common in the left superior PV. Potential mechanisms include reversible electroporation, highlighting the potential need for additional lesions and the value of a mandatory post-PFA "waiting period."

Keywords: Atrial fibrillation; Catheter ablation; Electroporation; Mapping; Pulmonary vein isolation; Pulsed-field ablation; Reconnection.