Reperfusion in acute myocardial infarction. A multicentre randomised trial of early intracoronary streptokinase and intravenous anisoylated plasminogen streptokinase activator complex in the United States.

To compare the reperfusion potential of anisoylated plasminogen streptokinase activator complex (APSAC), administered intravenously, and intracoronary streptokinase (the accepted standard for comparison in the United States), a randomised multicentre reperfusion trial was undertaken in the United States. A preliminary evaluation of results was made, based on the first 93 patients. Patients with acute myocardial infarction were studied angiographically, and those with coronary occlusion grade 0 or 1 were randomised and treated within 6 hours from symptom onset (mean 3 hours 25 minutes) with intracoronary streptokinase (20,000U bolus, then 2000 U/minute), or APSAC (30U over 2 to 4 minutes). Reperfusion was defined by a blinded reader as grade 2 or 3 flow after 90 minutes. Entry characteristics of patients in the 2 groups were comparable. Reperfusion rates were similar [19/39 (49%) of evaluable streptokinase patients and 19/43 (44%) of APSAC patients] and were dependent on the initial occlusion grade [38% of patients with grade 0 (streptokinase = 10/27, APSAC = 13/34), but 71% of patients with grade 1 (9/12, 6/9, respectively); p less than 0.02]. Grade 1 occlusion was present in 30% of patients treated within 4 hours, versus 16% treated at over 4 hours (p = 0.3). APSAC as a 2 to 4 minute infusion was well tolerated, and the change in mean blood pressure was minor (-6 mm Hg). Thus, APSAC and streptokinase provide similar reperfusion results, but APSAC is easier to administer, and shows excellent haemodynamic tolerance.

RCT Entities:   Population Interventions Outcomes