Real-World Experience With the Balloon-in-Basket Pulsed Field Ablation System for Pulmonary Vein Isolation and Ablation of Extra-Pulmonary Vein Sites.

BACKGROUND: A novel balloon-in-basket pulsed field ablation (PFA) system integrated with electroanatomical mapping has recently been introduced. However, real-world data on this technology, particularly for adjunctive posterior wall isolation (PWI) and extra-pulmonary vein sites, remain limited. OBJECTIVE: To evaluate the acute performance, safety, and feasibility of pulmonary vein isolation (PVI) and adjunctive lesions using a balloon-in-basket PFA system. METHODS: Consecutive patients with symptomatic paroxysmal or persistent AF undergoing ablation with the balloon-in-basket PFA system between February 2024 and February 2026 were included. Acute efficacy, procedural parameters, complications, exploratory haemolysis and renal biomarkers, and follow-up outcomes were assessed. RESULTS: A total of 133 patients were included; 94 (70.7%) had paroxysmal AF and 39 (29.3%) persistent AF. Acute PVI was achieved in 96.2% of cases. Adjunctive PWI was performed in 25.6% of patients, and additional extra-PV lesion sets were performed in 12 patients. Mean procedure, left atrial dwelling, and fluoroscopy times were 65.6 ± 16.4, 45.4 ± 15.4, and 12.7 ± 7.3 min, respectively, with no significant differences between PVI-only and PVI + PWI procedures. Two periprocedural complications occurred (1.5%; femoral arterial pseudoaneurysm, pericarditis). Exploratory biomarker analyses showed no evident haemolysis-related renal safety signal. Among 82 patients with ≥ 6 months of follow-up, late clinically documented atrial arrhythmia recurrence occurred in 14.6%. CONCLUSION: In this real-world experience, the balloon-in-basket PFA system showed high acute efficacy, low complication rates, and efficient workflow. Adjunctive PWI appeared feasible in selected patients, with exploratory comparisons showing no evident increase in procedural burden or additional biomarker safety signal.