Summary
Objective
The present study sought to determine the incidence of increased procoagulant activity
in patients with unstable angina (UAP), and to evaluate the relationship between cardiac
troponin T (cTnT) and molecular markers of hemostatic activation.
Method
We studied 44 patients with UAP further classified by plasma cTnT levels. All patients
received an antithrombotic therapy consisting of therapeutic doses of unfractionated
heparin and acetylsalicylic acid. Quantitative levels of cTnT and plasma concentrations
of fibrin monomers (FM), prothrombin fragments F1+2, thrombin antithrombin III complexes
(TAT), plasminogen and α2-antiplasmin were sampled serially within the first 48 h.
Results
Increased plasma concentrations of FM were detected in 45.5% of patients and were
more frequently present among those with cTnT concentrations >0.1 ng/ml (13 of 18
vs 7 of 26 patients, p = 0.003). In these patients, mean plasma concentrations of
FM were significantly higher than in patients with cTnT <0.1 ng/ml (7.93 ± 2.3 vs
3.12 ± 0.6 µg/ml, p = 0.02). There was a close relationship between plasma levels
of cTnT and FM (r = 0.74, p <0.004), prothrombin fragments F1+2 (r = 0.71, p = 0.046)
and a trend to significance was noted for TAT (r = 0.42, p = 0.055). No significant
correlation was observed with markers of the fibrinolytic system (plasminogen and
α2-antiplasmin). Plasma levels of cTnT >0.1 ng/ml identified a concomitant increase
of hemostatic markers with a sensitivity, specificity and positive predictive value
of 65, 79, and 72% for FM, 63, 76, and 67% for prothrombin fragments F1+2, and 58,
66, and 39% for TAT, respectively.
Conclusions
In patients with UAP, cTnT identifies patients with increased procoagulant activity
and is closely related to plasma levels of molecular markers of hemostatic activation.
Therefore, cTnT alone or in combination with one of these markers may be helpful to
identify patients requiring more potent antithrombin or antiplatelet therapy.
Key words
Unstable angina - troponin T - procoagulant activity - unfractionated heparin
