Lack of association between cardiac troponin T and D-dimer in the evaluation of myocardial damage

Acute myocardial infarction (AMI) disrupts cardiac cell membranes, releasing intracellular cardiac proteins into the vascular system. Some of these proteins, including the cardiac troponin subunits T and I, have proven useful for diagnosing myocardial damage. Intracoronary thrombosis plays a key role in the pathogenesis of AMI, and the formation of an occlusive thrombus usually precedes the development of myocardial damage. To evaluate whether there is an association between the size of intracoronary thrombosis and myocardial damage, we analyzed D-dimer and cTnT levels in blood samples from patients suspected to have myocardial damage. We investigated 102 patients who were admitted to emergency service for suspected myocardial damage. D-dimer was assessed with the use of the immunoassay Liatest D-dimer, and cTnT levels were measured with an electrochemiluminescence immunoassay (Troponin T STAT). D-dimer levels were lower in patients with cTnT < 0.01 than in patients presenting cTnT > 0.01 ng/mL. We investigated the relationship between D-dimer and cTnT levels in the patients with cTnT > 0.01 ng/mL (0.40 +/- 0.10 ng/mL), and no significant agreement (r = 0.20, P > 0.05) was observed. The levels of D-dimer were not associated with the levels of cTnT in patients with cTnT > 0.01 ng/mL.