Fibrinolysis with recombinant streptokinase affects the prognostic value of cardiac troponin I in acute myocardial infarction: a ten-day follow-up

The objective of this multicentre study was to identify the concentrations of cardiac troponin I having a higher probability of cardiovascular and extracardiovascular complications in patients with acute myocardial infarction that were treated with or without fibrinolysis at the intensive care units. These patients were followed for 10 days and divided into two prognostic groups: one without complications (n = 53) and other with clinical complications (n = 28). The plasma extracted from 3 h to 72 h after the onset of symptoms was retrospectively evaluated in an enzyme linked immunoadsorbent assay amplified with streptavidin-biotin for quantifying cardiac troponin I. About 45% of the patients had received recombinant streptokinase for fibrinolysis, from the onset of the symptoms and up to 6 hours. In the fibrinolysis group (n = 32), the concentrations of cardiac troponin I of complicated patients were similar to uncomplicated patients. Cardiac troponin I concentrations in patients without fibrinolysis (n = 49) were higher in complicated than in non-complicated patients (W = 287, p = 0.016). The biological activities of other cardiac biomarkers in complicated patients were as high as in uncomplicated patients treated with or without fibrinolysis. The concentration of cardiac troponin I of 2 ng/mL or higher, was a good predictor of the risk of clinical complications in patients without fibrinolysis (odds ratio: 6.6; 95% confidence interval: 1.5-29.4). In the infarction patients without therapeutic fibrinolysis, cardiac troponin I concentrations could be used to stratify them at the intensive care units and may be evaluated as an indicator of fibrinolysis in other studies.