Benign early repolarization: electrocardiographic manifestations and differentiation from other ST segment elevation syndromes.

Early repolarization, also known as benign early repolarization (BER) or normal variant, is noted in approximately 1% of the population and in up to 48% of patients seen in the emergency department with chest pain. BER represents a benign variant of the normal electrocardiogram and is one of several syndromes producing electrocardiographic ST segment elevation. BER electrocardiographically includes diffuse or widespread ST segment elevation, upward concavity of the initial portion of the ST segment, notching or slurring of the terminal QRS complex, and concordant T waves of large amplitude. This article focuses on BER and includes a discussion of the electrocardiographic tools useful in making this diagnosis and in distinguishing BER from other ST segment elevation syndromes.