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.