Background:

Pulsed field ablation (PFA) has recently been introduced as a novel routine ablation technology for paroxysmal atrial fibrillation (PAF). Only a few small clinical studies have been published on the mid- and long-term outcome. Herein, we present the six-month clinical outcomes of PFA in PAF.

Methods:

In PAF patients, PVI in conscious sedation using a steerable sheath and a pentaspline over-the-wire basket and flower PFA catheter was performed. In a subset of patients, pre- and post-ablation high-density bipolar voltage 3D maps (Carto 3D) were performed. Procedural parameters, acute success, in-hospital safety and arrhythmia recurrence were assessed over 6-month follow-up. Efficacy was evaluated by freedom from a ≥ 30-sec. recurrence of AF/atrial flutter (AFL)/atrial tachycardia (AT). Follow-up included 7-day Holter ECGs and/or telephonic interviews at days 90 and 180 after ablation.

Results:

This study included a total of 108 patients (mean age: 65±10 years; 44% female). Mean CHA₂DS₂-VASc-score was 2,3±1,7. Median duration since first AF diagnosis was 21 [IQR: 3 to 58] months. Pre- and post-ablation high-density maps were performed in 36/108 (33%) of patients. Skin-to skin procedure time was 78±35 min. Fluoroscopy time and dosis area product were 19±7 min and 5,56±4,64 Gy.cm², respectively. Left atrial dwell time of the PFA catheter was 27±11 min. Acute pulmonary vein isolation rate was 100% of PVs using PFA only. Primary adverse events occurred in 3.7% of patients (1 groin hematoma, 2 pericardial tamponades, 1 stroke with lethal outcome). Five patients were lost to FU. During a mean FU of 205±84 days, 81 of 103 patients (79%) remained free of any symptomatic or documented AF/AFL/AT episode after a single procedure. In 22 (21%) patients at least one episode of AF/AFL/AT was documented. In 6/22 (27%) patients, a re-do procedure was performed. In 2/6 (33%) patients, a reconduction of the PVs (1 LIPV, 1 posterior carina on both sides) was seen. In the remaining 4/6 (67%) patients, during re-do procedure typical or atypical flutter was treated, in presence of durable PV isolation. 

Conclusions:

PVI using PFA results in a reasonable 6-month atrial arrhythmia recurrence rate and safety profile. The success rate may be reduced due to the long duration since first AF diagnosis. PV reconduction rate during re-do procedure was 33% in a limited number of patients.