The ECG pattern of early repolarization has historically been regarded as a benign ECG variant, but during the past few years, this concept has been challenged based on multiple reports linking the ER pattern with an increased risk of sudden cardiac death.

Malignant vs. benign patterns of ER

There are 3 criteria which raise arrhythmia risk in early repolarization;
1- ST elevation in inferior leads
2- J-wave elevation >2 mm
3- Horizontal ST elevation
(J.T. Tikkanen, H.V. Huikuri. Characteristics of malignant vs benign electrocardiographic patterns of early repolarization. J Electrocardiol 2015)