Characteristics of Early Repolarization Pattern in the Iranian Population

Background: The early repolarization pattern (ERP) has been considered a normal variant in electrocardiography (ECG) for a long time. Nevertheless, increasing evidence has demonstrated its association with adverse outcomes. Objectives: The present study aimed to evaluate the prevalence of ERP in the Iranian general population and demonstrate its clinical and ECG correlates. Methods: A cross sectional study, comprising 1424 consecutive healthy adult individuals, was conducted at two university based hospitals in Tehran, Iran in 2012-2013. The ERP prevalence, clinical characteristics and ECG morphology were investigated in volunteers. Results: ERP was present in 136 out of 1,424 people (9.6%). Slurring comprised the most frequent morphology (41.2%) followed by notching. ERP was predominantly positive in inferior leads (47.8%) followed by lateral leads (30.1%). There was also a significant male preponderance in the ERP positive group (81.6%). The mean diastolic pressure was significantly lower in the ERP positive group versus the ERP negative group (77.3 + 7.9 mmHg vs. 78.8 + 10.5 mmHg) (P = 0.03). However, despite a lower systolic blood pressure in the ERP positive subjects (120.9 + 12.6 mmHg vs. 123.1 + 14.8 mmHg), the difference was not statistically significant (P = 0.06). Conclusions: ERP was present in 9.6% of healthy Iranian individuals with a higher frequency in inferior leads and slurring as the most prevalent morphology. Additionally, there was a male preponderance and middle-aged trend for ERP.