Prognostic role of plasminogen—activator—inhibitor—1 levels in treatment with streptokinase of patients with acute myocardial infarction

Background: The antifibrinolytic effect of plasminogen—ac—tivator—inhibitor type 1 (PAI—1) may be responsible for delays in reperfusion and/or reinfarctions after streptokinase (STK) therapy in patients with acute myocardial infarction (AMI). Hypothesis: This study aimed to demonstrate the prognostic role of pretreatment PAI—1 levels for the outcome of STK therapy in patients with AMI, depending on reperfusion and/or reinfarction. Methods: The mean pretreatment PAI—1 level of 104 patients with AMI, treated with STK, determined by chro—mogenic method, was 5.8 ± 8.6 U/ml, range 0.3—66.2 U/ml. Streptokinase therapy was successful when reperfusion was achieved, as assessed noninvasively, without subsequent rein—farction; it failed when reperfusion was delayed and/or rein—farction developed. Results: Fibrinolysis with STK failed significantly in patients with elevated pretreatment PAI—1 levels (p < 0.05), especially with levels >4.0 U/ml (p<0.01). The mean pretreatment PAI—1 level was significantiy higher in unsuccessfully treated patients. Multivariate statistical testing demonstrated that among pretreatment variables, elevated PAI—1 activity was the most significant independent risk factor of failed fibrinolysis with STK. Conclusions: Among pretreatment variables, elevated pretreatment PAI‐1 activity in patients with AMI was the most significant independent risk factor of failed fibrinolysis with STK, especially at levels > 4.0 U/ml.