Idiopathic Ventricular Fibrillation Triggered by Purkinje-Related Extrasystoles: State-of-the-Art and Novel...

Ventricular fibrillation (VF) is the primary arrhythmia causing sudden cardiac death. While typically linked to structural heart disease, a significant subset of VF episodes-especially in younger individuals-is triggered by focal ectopy from the His-Purkinje system (HPS). The HPS possesses distinct electrophysiological properties that make it inherently susceptible to arrhythmogenesis. It serves a dual role, acting as both a primary source of initiating premature ventricular complexes through abnormal automaticity and triggered activity (early and delayed afterdepolarizations), and as a critical substrate maintaining VF via micro-re-entrant circuits. This narrative review comprehensively synthesizes current knowledge on Purkinje-triggered VF, from its epidemiology and clinical setting to its underlying pathophysiological and ionic mechanisms of arrhythmia initiation and perpetuation. Finally, we critically evaluate contemporary diagnostic and management strategies, contrasting conventional focal trigger-based ablation with evolving substrate-based approaches such as Purkinje "de-networking."