First-in-human experience and one-year outcomes using a novel conformal pulsed-field ablation balloon catheter for pulmonary vein isolation in paroxysmal atrial fibrillation

Background Thermal balloon catheters have improved the efficiency of pulmonary vein isolation (PVI) in atrial fibrillation (AF). Reports assessing additional safety and effectiveness of pulsed field ablation (PFA) balloon catheters for PVI are limited. This study aims to assess the safety and effectiveness of a conformal PFA balloon catheter for PVI in paroxysmal AF. Methods 35 patients with paroxysmal AF (PAF) were treated with a PFBalloon catheter (Biphasic, Bipolar, 750 V). The balloon was inflated with 10:1 saline/contrast, with volume adjusted for spherical wide-antral or pear-shaped ostial-junction PV ablation to ensure optimal tissue contact. The primary safety endpoint was absence of periprocedural primary adverse events. The primary effectiveness endpoint was acute PVI. The secondary effectiveness endpoint included durable PVI assessed by remapping at three months post-ablation and 1-year clinical outcomes. Results All targeted PVs (142/142) in 35 patients were acutely isolated, with 32.3 ± 4.5 applications per patient and 7.9 ± 1.0 per vein. Procedure and left atrial dwell times were 133 ± 46 and 56 ± 25 min, respectively. No hemolysis-related acute kidney injury or severe device-related complications occurred. PVI durability was 76.0% (19/25) per patient and 93.1% (95/102) per vein. After a median follow-up of 367 (interquartile range 357–380) days, 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia (AF/atrial flutter/atrial tachycardia) ≥30 s was 90.7% (95% CI, 81.2%–100%). Conclusions The conformal PFBalloon catheter demonstrated favorable safety, efficiency, and effectiveness for PVI in PAF patients, achieving durable lesions and a high rate of freedom from atrial arrhythmias recurrence. Trial registration clinicaltrials.gov NCT07320976.