Evaluation of ST segment deviation on ۱۵-lead ECG in patients with Acute Coronary Syndrome (ACS)

Background & Objective: Patients with ischemic heart disease classified to two major groups: patients with stable angina and patients with Acute Coronary Syndrome (ACS). Previous studies showed that posterior segment of left ventricle is a silent segment on ECG, and routine ۱۲ leads electrocardiogram (ECG) is not sensitive for evaluation of posterior infarction. This study designed for evaluation of ST segment deviation on posterior leads of ECG in patients with ACS at Beheshti hospital in ۲۰۰۲. Materials & Methods: This is a descriptive-analytical and prospective study. In ۳۴۷ patients with diagnosis of ACS who were admitted in the emergency department, ۱۲ leads ECG with additional three leads (V۷-V۸-V۹) was carried out. For statistical analysis, calculation of percentages for sensitivity, odds ratios, and %۹۵ confidence intervals was performed. Results: Major abnormalities (ST elevation ۱mm and ST depression  ۱mm) were found on the extra three leads in %۲۱.۶ (۷۵ out of ۳۴۷). Sensitivity of ST segment elevation for acute myocardial infarction on ۱۲ versus ۱۵ leads increased from %۶۸.۵ to %۹۰.۷ (P=۰.۰۰۰۵). Sensitivity of ST segment depression for acute myocardial infarction on ۱۲ versus ۱۵ leads increased from %۳۱.۵ to %۴۰.۷ (p=۰.۱۵۷). Sensitivity of ST segment elevation for unstable angina (۲۳۹ cases) on ۱۲ versus ۱۵ leads from zero to %۵ and sensitivity of ST segment depression for unstable angina on ۱۲ versus ۱۵ leads increased from %۳۱.۸ to %۳۶.۸ (P=۰.۲۵ ). Conclusion: The ۱۵-leads ECG provides increased sensitivity of detecting ST–segment deviation in acute myocardial infarction and unstable angina.

کلیدواژه ها:

Myocardial infarction ، Unstable angina ، Acute Coronary Syndrome ، ۱۵ leads ECG