ST Elevation and Inverted T Wave as Another Normal Variant Mimicking Acute Myocardial Infarction: The Prevalence, Age, Gender, and Racial Distribution

BACKGROUND: Early repolarization (ERP) as a normal variant is a well-recognized ECG entity. There is another normal variant of ST elevation (STTNV) in the midprecordial leads, which is distinctively different from ERP in that the T waves are inverted in these leads while they are upright and tall in ERP. These findings can be easily mistaken for acute myocardial infarction or pericarditis. The purpose of this study is to publicize this entity and to determine its prevalence, age, gender, and racial distributions. METHODS: All ECGs taken in adults at a Minneapolis hospital in 2007 were reviewed and individuals with the following ECG findings were identified: 1-3 mm ST elevation ending in an inverted T wave in midprecordial leads with preserved R waves. RESULTS: A total of 11,424 patients (5997 men, 5427 women) had one or more ECGs in 2007. STTNV was seen in 101 patients, 97 (96%) of whom were black. Seventy-seven of 2084 (3.7%) black men and 20 of 2020 (1%) black women had STTNV. It was rare in other races (0 to 0.7%), particularly in white patients (1 of 5099 patients). It seems to be evenly distributed throughout the age. The ECG findings normalized in all 6 patients who underwent a treadmill stress test. CONCLUSIONS: This entity is seen almost exclusively in blacks (3.7% of men, 1% of women), and is more or less evenly distributed throughout the age. Whether this variant is more often associated with malignant ventricular arrhythmias remains to be determined.