Plasma levels of tissue plasminogen activator/plasminogen activator inhibitor-1 complex and von willebrand factor are significant risk markers for recurrent myocardial infarction in the Stockholm Heart Epidemiology Program (SHEEP) study

An impaired fibrinolytic function due to elevated plasma levels of plasmino gen activator inhibitor (PAI)-1 activity or tissue plasminogen activator (t PA) antigen is correlated with the development of myocardial infarction (MI ) in patients with manifest coronary heart disease. Recently, methods for d etermining the specific tPA/inhibitor complexes constituting tPA antigen in plasma have become available. In the Stockholm Heart Epidemiology Program (SHEEP) study, 86 of 1212 MI patients, subjected to blood sampling in a met abolically stable period, suffered reinfarction before the end of 1996. The se individuals have been compared with an approximately equal number of mat ched MI patients without recurrence and a group of matched healthy control subjects regarding the plasma concentrations of some hemostatic factors. Th e hemostatic compounds studied (fibrinogen, von Willebrand factor, tPA anti gen, PAI-1, and the tPA/PAI-1 complex) were typically higher in the groups (men and women) with recurrence of MI compared with those without. The plas ma concentrations were also typically higher in the pooled groups of patien ts compared with the groups of healthy control subjects. The largest betwee n-group differences were found for the plasma tPA/PAI-1 complex. The crude odds ratio for reinfarction associated with higher concentration (greater t han or equal to 75th percentile among the control subjects) of tPA/PAI-1 wa s 1.8 (95% CI 1.1 to 3.1); the corresponding crude odds ratio for von Wille brand factor was 2.3 (1.3 to 4.0). The tPA/PAI-1 complex correlated strongl y with PAI-1 and tPA antigen in all groups and with serum triglycerides and body mass index in all groups except for women with reinfarction. An incre ased plasma level of tPA/PAI-1 complex is a novel risk marker for recurrent MI in men and women. Most likely, increased plasma levels of tPA/PAI-1 com plex reflect impaired fibrinolysis, because the correlation with PAI-1 is s trong. Further support is obtained indicating that the plasma concentration of von Willebrand factor is also an important risk marker for recurrent MI .