Early repolarization

Benign early repolarization also known as early repolarization is found on ECG in about 1% of those with chest pain. It is diagnosed based on an elevated J-point / ST elevation where the ST segment is concave up. It is believed to be a normal variant.

Benign Early Repolarization that occurs in the inferior and lateral portion of the heart muscle is associated with ventricular fibrillation. The association, revealed by research performed in the late 2000s, is small.

Research in the late 2000s has linked this finding when found in the inferior and lateral ECG leads to ventricular fibrillation particularly in those who have fainted or have a family history of sudden cardiac death. The magnitude of the association is however small.

On an electrocardiogram (EKG or ECG), benign early repolarization may produce an elevation of the ST segment, similar to that observed in heart attacks (myocardial infarction). However, with benign early repolarization, the ST segment is usually concave up, rather than concave down (as with heart attacks), and there is a notable absence of reciprocal changes suggestive of ischemia on the EKG.

Benign early repolarization occurs in about 1 to 2 percent of the general population. The prevalence is higher in men, young adults, adolescent Africans, African Americans, and athletes.

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