Early Repolarization: Not Benign Any More- the J-Wave Syndromes

An early repolarization (ER) pattern characterized by J-point elevation, slurring of the terminal part of the QRS and ST-segment elevation has been traditionally considered to be totally benign over the past decades. A flurry of data derived from recently published studies demonstrates that an ER pattern in inferior or inferolateral leads, named early repolarization syndrome (ERS), is associated with increased risk for sudden cardiac arrest (SCA), being responsible for some cases of idiopathic ventricular fibrillation (IVF). Current evidence support the notion that although ERS and Brugada syndrome (BrS) show discrete differences, they also share similar clinical, electrocardiographic and pathophysiological features, especially concerning the presence of amplified J-waves; thus, they can be considered to represent a continuous spectrum of phenotypic expression, termed J-wave syndromes. Research has provided us with fascinating insights into the underlying mechanisms responsible for repolarization abnormalities and we presently have more evidence to implement reliable risk stratification methods to patients with ER. However, many unanswered questions remain and still need to be addressed in future studies