Effects of negative T wave in electrocardiography on prognosis of post-myocardial infarction patients

BACKGROUND: Negative T (NT) wave in electrocardiography (ECG) is one of the important factors in determining short- and long-term outcomes in patients with acute myocardial infarction (MI). In this study, we compared clinical and paraclinical findings in post-MI patients according to presence or absence of NT wave. METHODS: A cross-sectional study was conducted on patients with acute ST elevation MI who presented to Shahid Modares Hospital (Tehran, Iran) during ۲۰۰۹-۱۰. After undergoing streptokinase therapy, demographic characteristics and ECG and exercise test findings of the subjects were compared based on the presence or absence of NT wave. RESULTS: Overall, ۱۱۶ patients including ۶۹ cases with NT wave (NT group) and ۴۷ cases without NT wave (PT group) were enrolled (mean age: ۵۳.۷ ± ۷.۱ vs. ۵۴.۱ ± ۶.۸ years old). Mortality rate during the first five days was ۱۳% in the NT group and ۲۹% in the PT group (P < ۰.۰۵). Ejection fraction values of the NT group were significantly higher than the PT group (P = ۰.۰۰۵). However, left ventricular end-diastolic diameter of the NT group was significantly less than the PT group (P = ۰.۰۰۵). Moreover, ST segment depression was significantly less frequent in the NT group compared to the PT group. CONCLUSION: Patients with ST elevation MI accompanying with NT wave in ECG versus have better prognosis and myocardial function than similar patients without NT wave. Therefore, invasive procedures should be recommended for patients without NT wave.   Keywords: Echocardiography, Exercise Test, Myocardial Infarction, Negative T Wave, Echocardiography