High-voltage pulsed field ablation: a novel strategy for multiple redo ventricular tachycardia ablation in nonischemic cardiomyopathy patients
E Chiarazzo, M Marino, V M La Fazia, C Gianni, S Mohanty, G Stifano, W Bode, K Awad, D Burkardt, J Gallinghouse, R P Horton, A Al-Ahmad, L Di Biase, A NataleAbstract
Background
Catheter ablation ventricular tachycardia (VT) in non-ischemic 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.
Purpose
The aim of our study is to evaluate the safety and feasibility of hv-PFA during VT ablation.
Methods
This single-center series included consecutive NICM patients undergoing repeat ablation of recurrent monomorphic VT with an 8.5-French 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 absence of residual abnormal electrograms within bipolar voltage area <1.5mV. Devices and mapping systems integrity was monitored during the procedure. Follow-up data were collected during in-office evaluations and device remote monitoring.
Results
Seven consecutive patients [mean age 58±10.4 years; female (1) 14.3%] underwent a total of nine procedures, as one patient underwent three ablations for VT recurrence. Mean number of prior procedures was 2.29±1.11. A scar homogenization strategy was applied in all procedures (median number of lesions, 14 [IQR8]). Procedural success was achieved in all patients. During a mean follow-up of 6 months (193±128 days), arrhythmic recurrence occurred in 2 (28.6%) patients. Electromagnetic interference resulted in defibrillator malfunction in 2 (22.2%) procedures, requiring generator replacement, and mapping-system malfunction in 3 (33.3%) procedures.
Conclusion
Preliminary findings from this prospective series show efficacy of hv-PFA in NICM patients with prior multiple unsuccessful VT ablation. Further studies are required to define the safety profile of this novel ablation system.