Figure 1. Definite and Probable Patterns of ER.

Definite early repolarization (ER) is defined as the presence of ST-segment J elevation >1 mm in ≥50% of beats, T-wave amplitude ≥5 mm, prominent J point, upward concavity of the ST segment, and distinct notch or slur on the downstroke of the R wave in any of leads V3 to V6 or ST-segment J elevation >2 mm in ≥50% of beats, T-wave amplitude ≥5 mm, prominent J point, and upward concavity of the ST segment in any of leads V3 to V6. Probable ER is defined as ST-segment J elevation >1 mm in ≥50% of beats, prominent J point, upward concavity of the ST segment in any of leads V3 to V6, and T-wave amplitude ≥8 mm in any of the chest leads.