Contributor: Peter Bakes, MD Educational Pearls: Two main differentials for wide complex tachycardia (WCT) include ventricular tachycardia (most common) and supraventricular tachycardia with aberrancy Brugada syndrome and Wolff-Parkinson White are potential causes Arrhythmogenic right ventricular dysplasia is a rare congenital cause of WCT that should be considered in younger patients presenting with WCT References B Garner J, M Miller J. Wide Complex Tachycardia - Ventricular Tachycardia or Not Ventricular Tachycardia, That Remains the Question. Arrhythm Electrophysiol Rev. 2013;2(1):23-29. doi:10.15420/aer.2013.2.1.23 Katritsis DG, Brugada J. Differential Diagnosis of Wide QRS Tachycardias. Arrhythm Electrophysiol Rev. 2020;9(3):155-160. doi:10.15420/aer.2020.20 Li KHC, Bazoukis G, Liu T, et al. Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) in clinical practice. J Arrhythm. 2017;34(1):11-22. Published 2017 Dec 21. doi:10.1002/joa3.12021 Summarized by John Spartz, MS3 | Edited by Erik Verzemnieks, MD