Pulsed Field Ablation for Ventricular Arrhythmia in Repaired Tetralogy of Fallot.

BACKGROUND

Ventricular arrhythmias are a major late complication in patients with repaired Tetralogy of Fallot (TOF), frequently originating from slow conduction zones within surgical isthmuses. Pulmonary valve replacement (PVR) may limit future ablation access, prompting interest in pre-emptive substrate modification. Pulsed field ablation (PFA) is a novel nonthermal ablation modality with potential safety advantages.

CASE SUMMARY: A 45-year-old man with repaired TOF and severe pulmonary regurgitation underwent a pre-PVR electrophysiology study, which identified a slow conduction zone at isthmus 3, located between the right ventricular outflow tract and the ventricular septal defect patch. Focal PFA achieved bidirectional block without complications.

DISCUSSION: This first reported use of focal PFA for ventricular arrhythmia substrate modification in TOF demonstrates its feasibility and short term safety, supporting its potential role in pre-emptive arrhythmia management before structural interventions.

TAKE-HOME MESSAGES: This case demonstrates the feasibility of using focal PFA for the treatment of ventricular arrhythmia in patients with repaired TOF. It highlights the role of pre-emptive substrate modification before PVR in patients with repaired TOF.