Abstract
BACKGROUND: Left ventricular excessive trabeculation (LVET) is associated with malignant ventricular arrhythmias. Polymorphic ventricular tachycardia (PVT) remains particularly challenging, with limited evidence supporting catheter ablation (CA). CASE SUMMARY: A 53-year-old woman with LVET presented with drug-refractory PVT triggered by short-coupling ventricular premature contractions. Electroanatomical mapping revealed Purkinje and delayed potentials within the left ventricular septum, localized at the base of a recessed trabecular region. CA targeting these signals successfully eliminated inducible PVT. The patient has remained free from recurrent malignant arrhythmias over 11 years of follow-up. DISCUSSION: This case highlights the role of the Purkinje fiber network within deep trabeculations in triggering life-threatening arrhythmias. Few reports describe effective CA of PVT in LVET, underscoring the novelty and clinical relevance of this finding. TAKE-HOME MESSAGE: Deeply recessed Purkinje fibers within LVET can serve as critical triggers for malignant ventricular arrhythmias.