High-Voltage Pulsed Field Ablation: Novel Strategy for Redo Ventricular Tachycardia Ablation in Nonischemic...

Catheter ablation of ventricular tachycardia (VT) in nonischemic cardiomyopathy (NICM) remains particularly challenging, as arrhythmogenic substrates are often deep and heterogeneous within the myocardium. To overcome these limitations, a novel high-voltage pulsed field ablation (hv-PFA) system is under investigation.

The aim of our study was to evaluate the safety and feasibility of hv-PFA during VT ablation.

This single-center series included consecutive NICM patients undergoing repeat ablation of recurrent monomorphic VT with an 8.5-F force-sensing hv-PFA catheter between July 2024 and August 2025. A scar homogenization approach was used in all patients. Procedural success was defined as noninducibility of any VT and absence of residual abnormal electrograms within bipolar voltage area <1.5 mV. Device and mapping system integrity was monitored during the procedure. Follow-up data were collected during in-office evaluations and remote device monitoring.

Seven consecutive patients (mean age 58 ± 10.4 years; 1 female [14.3%]) underwent a total of 9 procedures, as 1 patient underwent 3 ablations for VT recurrence. The mean number of prior procedures was 2.29 ± 1.11. A scar homogenization strategy was applied in all procedures (median 14 lesions [Q1-Q3: 9-17 lesions]). Procedural success was achieved in all patients. During a median follow-up of 10 months (320 days [Q1-Q3: 183-407 days]), arrhythmic recurrence occurred after 3 (33.3%) of 9 procedures in 2 (28.6%) of 7 patients. Electromagnetic interference resulted in defibrillator malfunction in 2 (22.2%) procedures, requiring generator replacement, and mapping system malfunction in 3 (33.3%) procedures.

Preliminary findings from this prospective series show efficacy of hv-PFA in NICM patients with prior multiple unsuccessful VT ablations. Further studies are required to define the safety profile of this novel ablation system.