DEPARTMENT OF CARDIOLOGY, IMAM KHOMENI MEDICAL CENTER, TEHRAN UNIVERSTY OF MEDICAL SCIENCES, TEHRAN, IRAN
Background- Normalization of ST segment elevation after thrombolytic therapy for acute myocardial infarction (AMI) is accepted as an indirect method for reperfusion. In this study, we found that further ST elevation during the first hour of thrombolytic therapy is accompanied with better left ventricular (LV) function and patency of infarct-related artery (IRA) than cases without further ST elevation.
Methods- From Sept. 2000 to Aug. 2002, one hundred patients who had AMI (60% anterior, 37% inferior and/posterior, 3% combined anterior and inferior) and received streptokinase (SK) were evaluated for ST segment changes, LV function and IRA residual stenosis. 76% of them were male, and their mean age was 56.59±11.84 years.
Results- Further ST elevation occurred in 46 patients (Group 1), and 54 patients exhibited no additional ST segment elevation (Group 2). LV ejection traction (LVEF) was higher in Group 1 than in Group 2 (48.58±6.72%vs. 41.75±8.91%, p<0.001). It was more significant in patients with anterior MI (48.21±6.83%vs. 39.68±8.12%,p<0.001) than in patients with inferior MI (50±5.86%vs. 46±8.52%,p=NS). Group 2 had more severe IRA residual stenosis than Group 1 (83.33±18.21%vs. 67.08±25.44%,p=0.034).
Conclusions- This study indicates that further ST elevation during the first hour of thrombolytic therapy in patients with AMI is in favor of reperfusion and a better outcome.