The effect of thrombolytic therapy with anisoylated plasminogen streptokinase activator complex on the indicators of myocardial salvage.

The role of anisoylated plasminogen streptokinase activator complex (APSAC) in acute myocardial infarction, in effecting thrombolysis, in limiting infarct size and in preserving myocardial function, was assessed by comparing APSAC and placebo in a double-blind, randomised trial. Between October 1984 and April 1985, 43 patients (mean age 57.3 years) with evolving infarctions (19 anterior/24 inferior) were randomised. All patients received treatment within 3 hours of the onset of pain. Patients over 70 years of age or with contraindications to thrombolytic therapy were excluded. Response to therapy was assessed by comparing reductions in summated ECG R wave amplitude and changes in QRS score at 24 hours and 7 days in the leads with ST abnormalities on admission. Radionuclide ejection fractions (EF) were performed 2 to 6 months after infarction. Evidence of successful reperfusion was based on non-invasive parameters. Mean time to peak cardiac enzyme release was shorter in the active treatment group, indicating effective thrombolysis (11.5 hours vs 17.6 hours; p less than 0.01). No differences were found in R wave reduction or QRS score at either 24 hours or 7 days, between active and placebo groups in total or when divided by infarct site. No difference was seen between the EFs of the groups in total or between inferior infarct groups. The mean EF of the treated anterior group was higher than that of the untreated group (p less than 0.05). Successful thrombolysis was seen in the actively treated group. Evidence of myocardial salvage and preservation was seen among treated patients with anterior infarcts only.