Ventricular Tachycardia Ablation in Late-Onset Phenotype Fabry Disease: A Case Report

Abstract Background Fabry disease is an X-linked lysosomal storage disorder that can cause progressive cardiomyopathy, myocardial fibrosis, conduction disease, and malignant ventricular arrhythmias. Ventricular tachycardia (VT) ablation in advanced Fabry cardiomyopathy is challenging, particularly in patients with extensive scar and left ventricular assist device (LVAD) support. Case summary A 71-year-old man with late-onset Fabry disease, confirmed by endomyocardial biopsy showing myelin body accumulation, reduced α-galactosidase A activity, elevated plasma Gb3, developed severe left ventricular dysfunction, extensive late gadolinium enhancement, LVAD implantation, and complete atrioventricular block requiring dual-chamber pacemaker implantation. He presented with recurrent palpitations and near-syncope. Device interrogation revealed multiple VT episodes, including one episode degenerating into ventricular fibrillation, and surface electrocardiography documented wide-complex tachycardia with right bundle branch block morphology and an inferior axis. An electrophysiological study was performed using an antegrade transseptal left ventricular approach. Intracardiac echocardiography was used to delineate the LV cavity and LVAD position, facilitating safe catheter navigation and mapping while avoiding interference with the LVAD. Endocardial mapping demonstrated diffuse late potentials, low-voltage substrate, and deceleration zones involving the basal-to-mid inferolateral left ventricle. Substrate modification targeting these abnormal electrograms eliminated inducible ventricular premature complexes. No recurrent VT episodes were detected on subsequent pacemaker interrogation. Discussion This case highlights the complex arrhythmogenic substrate of late-stage Fabry cardiomyopathy and the utility of intracardiac echocardiography-guided mapping in patients with LVAD support. Catheter ablation may provide short-term arrhythmia control, but in advanced Fabry disease, its role remains largely palliative.