EFFICACY OF PREHOSPITAL THROMBOLYTIC THERAPY FOR ACUTE MYOCARDIAL-INFARCTION

The efficacy and risk of prehospital thrombolysis for acute myocardial infarction (MI) were evaluated in a randomized trial. Patients received streptokinase, 500,000 U, and heparin, 10,000 U, intravenously within 5-10 minutes before (Group 1, n=50) or after (Group 2, n=50) hospital admission. One hundred patients took conventional therapy (Group 3). The mean time interval between the onset of symptoms and thrombolytic therapy was 2.2, 4.5, and 3.8 hours in Groups 1, 2, and 3, respectively (p<0.001). Severe hemorrhagies were absent. The rate of ventricular fibrillation was the same in Groups 1 and 3 prior to hospitalization. Left ventricular contractility was identical in Groups 1 and 2. By the end of the fourth week, Group 1 showed a 14 % increase in ejection fraction and a 14.5 % decrease in akinetic segment, these parameters substantially unchanged in Group 2. The MI size assessed by ECG and the maximum myoglobin concentrations was significantly less in Group 1 than that in Group 2. The patients from Group 1 had fewer MI complications than those from Groups 2 and 3. Three patients died in Group 1, 6 in Group 2, and 16 in Group 3. (p<0.05).