Fascicular Ventricular Tachycardias: Potential Role of the Septal Fascicle.

Ventricular tachycardias involving the fascicular system are amongst the most challenging and intriguing arrhythmias for cardiac electrophysiologists. Although some of the more common forms have been recognized clinically for decades, other variants continue to be characterized. Moreover, considerable uncertainty persists to date with regards to the mechanisms underpinning these arrhythmias. In this state-of-the-art review, we discuss the seminal historical and contemporary observations that have collectively advanced our understanding of fascicular ventricular tachycardias. From this base, we canvas the basic and clinical evidence supporting a potential role for the septal fascicular network and propose a new schema hypothesizing involvement of this fascicle. Although we focus primarily on the most common left posterior fascicular ventricular tachycardia, our discussion and proposal have mechanistic and therapeutic implications for the spectrum of fascicular arrhythmias.
Competing Interests: Funding Support and Author Disclosures Dr Wong is supported by a Mid-Career Fellowship from the Hospital Research Foundation and a Postdoctoral Fellowship from the National Heart Foundation of Australia; and his institution has received on his behalf lecture, travel, and/or research funding from Abbott Medical, Bayer, Boehringer Ingelheim, Medtronic, Novartis, Servier, St. Jude Medical, and Vifor Pharma. Dr Nogami has received honoraria from Abbott and Biosense Webster; and has received an endowment from Medtronic and DVx. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)