Differential diagnosis of acute pericarditis from normal variant early repolarization and left ventricular hypertrophy with early repolarization: an electrocardiographic study.

Background: Differentiation of ST-segment elevation on electrocardiogram (ECG) from acute pericarditis (AP), normal variant early repolarization (ER) and early repolarization of left ventricular hypertrophy (ERLVH) can be problematic. Hence, the authors evaluated the accuracy of the ST/T ratio in ECG to more optimally differentiate between AP, ST-segment elevation, ER and ERLVH.

Methods: Between September 2006 and July 2010, 80 patients were enrolled in this study consisting of 25 individuals with AP, 27 with ER and 28 with ERLVH. Each ECG was analyzed in a systematic manner including the measurement of PR interval, QRS duration, QT-segment duration, PR-segment deviation, ST-segment deviation and the height of T wave. The ratio of the height of ST segment to the height of T wave was measured in leads I, II, III, aVF and V2 through V6.

Results: The mean ages of the patients with AP, ER and ERLVH were 32 ± 16.5, 36 ± 15.4 and 53 ± 16 years, respectively. The ratio of the amplitude of ST segment to the amplitude of the T wave in leads I, V4, V5 and V6 proved to be a significant discriminator at a value of ≥0.25 (P < 0.05 for all).

Conclusions: Leads I, V4, V5 and V6 can all be used to differentiate AP from ER and ERLVH. When ST elevation is present in lead I, the ST/T ratio has the best predictive value (0.82) to more accurately discriminate between AP, ER and ERLVH.