Early repolarization
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Synonyms and keywords: early repolarization pattern; early repol; early repol variant
Overview
Early repolarization is defined as notching or slurring of the morphology of the terminal QRS complex or J-point elevation >0.1 mV above baseline in at least 2 lateral or inferior leads.[1] Early repolarization is a normal ECG variant that is most commonly seen in young males. It can be confused with ST elevation MI and pericarditis.
Natural History, Complications and Prognosis
A case control study of 120 post MI patients with implantable cardioverter-cefibrillators (ICDs) demonstrated that early repolarization was more frequently observed among patients with documented episodes of VT/VF (32% vs. 8%, p=0.005). The leads demonstrating early repolarization were more often the inferior leads (23% vs. 8%, p=0.03). A trend was observed for the lateral leads (V4-V6) as well (12% vs. 3%, p=0.11). In contrast, leads I and aVL were not commonly involved (3% vs. 0%). The morphology of the ST segment was critical and a notch in the ST segment was observed more frequently among patients with VT/VF (28% vs. 7%, p=0.008). In contrast, J-point elevation and slurring of the ST segment surprisingly were not associated with ventricular arrhythmias.[2]
Diagnosis
Differentiating Early Repolarization From Pericarditis
- Early repolarization is exacerbated by bradycardia, and carotid sinus massage or vagal maneuvers may exacerbate the variant.
- The red arrow points to a characteristic notch which is present at the J point in early repolarization as shown below:
Only lead V6 is used to distinguish between early repolarization and pericarditis. As shown in the figure below, if A/B > 25%, suspect pericarditis. If A/B < 25%, suspect early repolarization.
Diagnosis
Electorcardiographic Examples
