Plasma thrombomodulin activity, tissue factor activity and high levels of circulating procoagulant phospholipid as prognostic factors for acute myocardial infarction.

Several studies have indicated an association between haemostatic markers and acute myocardial infarction, but few or no studies refer to their activity. We studied plasma levels of 10 coagulation factors (fibrinogen, protein C, protein S, von Willebrand factor, D-dimers, factor VIIa, free tissue factor pathway inhibitor, tissue-type plasminogen activator, plasminogen activator inhibitor-1, thrombomodulin) and using new specific assays analysed the activity of plasma tissue factor (TFa), thrombomodulin (TMa), and procoagulant phospholipid in 46 consecutive patients with acute myocardial infarction at the time of hospital admission, and compared them with 34 healthy normal volunteers. Plasma levels of TFa, TMa, and procoagulant phospholipid were significantly higher in cases than in control patients (P < 0.001). In addition the ratio of TFa/free tissue factor pathway inhibitor was higher in patients than in controls, whereas the tissue-type plasminogen activator (t-PA)/plasminogen activator inhibitor-1 ratio was lower in patients. Interestingly, patients with an unfavourable outcome during a 2-month follow-up had higher levels of TFa, TMa, procoagulant phospholipid, a higher ratio of TFa/free tissue factor pathway inhibitor and a lower ratio of t-PA/plasminogen activator inhibitor-1 than patients who recovered. The combination of these different parameters reveals an increase in procoagulant activity as well as impaired fibrinolytic activity during the acute phase of an acute myocardial infarction. The association of the level of the activity of these three factors may provide a new tool to assess the prognosis of acute myocardial infarction. Further studies are needed to support our findings and to elucidate the clinical interest of measuring these factors.