Table 1.

ECG findings associated with an increased arrhythmic risk.

ECG Abnormality	Pathophysiologic Background	Clinical Setting
QRSf	Conduction delay from inhomogeneous activation of the ventricles due to myocardial scar	DCM, IDCM HCM, BrS LQTS, ARVD Cardiac Sarcoidosis
ER (“J-waves” or “J-point elevation”)	Altered ion channel function (alterations in sodium, potassium and calcium currents)	Young African men Athletes HCM
TW Inversion	Changes during phase three of the action potential	ARVD

BrS: Brugada syndrome; ER: early repolarization; ICM: ischemic cardiomyopathy; NICM: non-ischemic cardiomyopathy; HCM: Hypertrophic cardiomyopathy; ARVC: arrhythmogenic right ventricular cardiomyopathy; QRSf: QRS fragmentation; TW: T wave.