Purkinje-Related Ventricular Tachycardia and Ventricular Fibrillation Solved and Unsolved Questions

Of the monomorphic ventricular tachycardias, there are 4 specific tachycardias related to the Purkinje system: 1) idiopathic verapamil-sensitive fascicular ventricular tachycardia (FVT); 2) non-re-entrant FVT; 3) bundle branch re-entry and interfascicular re-entry; and 4) Purkinje-mediated VT in structural heart disease. Verapamil-sensitive FVT is classified into 4 types according to the location of the circuit: 1) left posterior type; 2) left anterior type; 3) left upper septal type;and 4) reverse type. And, in the left anterior and posterior types, there are septal and papillary muscle subtypes. Although macro-re-entry has been reported to be the mechanism underlying verapamil-sensitive FVT, recording the entire circuit is challenging. One possible reason is that the Purkinje-muscle junction may penetrate the myocardial layer as a part of the circuit. The Purkinje network may thus play an important role in the initiation and maintenance of ventricular fibrillation. Further, it has been reported that the development and the abnormalities of the Purkinje system are associated with the arrhythmogenesis of ventricular fibrillation. Furthermore, it has been reported that catheter ablation of trigger ventricular premature complexes, and/or de-networking of the Purkinje system, can be used as electrical bailout therapy. There is a hypothesis that the intramural Purkinje system is involved in the generation of J waves. Nevertheless, as there are still unresolved issues that must be debated and accurately analyzed, this review aims to discuss the solved and unsolved questions related to Purkinje-related arrhythmias. (J Am Coll Cardiol EP 2023;9:2172-2196) (c) 2023 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This article discusses Purkinje-related arrhythmias, including four specific ventricular tachycardias such as verapamil-sensitive fascicular ventricular tachycardia (FVT). The Purkinje system plays an important role in the initiation and maintenance of ventricular fibrillation, and its development and abnormalities are associated with arrhythmogenesis. Catheter ablation of trigger ventricular premature complexes and/or de-networking of the Purkinje system can be used as electrical bailout therapy.