Oka E, et al. - In this retrospective analysis of 30 patients (23 men; 39.2±19.1 years) with acute myocarditis, researchers determined the prevalence as well as the importance of the early repolarization electrocardiographic (ER-ECG) pattern, with a focus on its mechanistic insight based on the cardiac magnetic resonance results. Terminal QRS notching or slurring with an amplitude of >0.1 mV in at least two inferior or lateral leads defined an ER-ECG pattern, which was seen in nine cases (early repolarization [ER] group), while broad ST-segment elevation or pathological Q waves were detected in the remaining 21 cases (non-ER group). Findings revealed a brief and reversible ER-ECG pattern in acute myocarditis, which was not related to a worse prognosis. A mechanistic insight into the ER-ECG pattern might be offered by inflammation/swelling localized to the left ventricular epicardium due to acute myocarditis.