• Early repolarization is defined as J-point elevation ≥ 1 mm in ≥ 2 continguous inferior and/or lateral leads.
• On ECG, there is either a notch (“fish hook”) or slur at the end of QRS as shown below.
• Most early repolarizations are benign (also referred to as "benign early repolarization" or "early repolarization pattern"). When early repolarization is associated with symptomatic arrhythmias (e.g. polymorphic ventricular tachycardia, ventricular fibrillation), it's called early repolarization syndrome (ERS).
• ERS is thought to be an inherited disorder in which cardiac Na, K, and Ca ion channels are malfunctional.
• ECG features associated with increased risk of arrhythmias include:
J point elevation ≥ 2 mm
Horizontal or downsloping ST segment
• Early repolarization might be mistaken for acute pericarditis, but in early repolarization, there is no PR depression, ST elevation is not diffuse in all leads.
• Comparing to STEMI, ST segment in early repolarization has a concave shape and ST-T changes do not evolve over time.
