Alterations of Hemostatic Parameters, Acute Phase Reactants and Troponin T in Unstable Angina: Prevalence and Clinical Implications

pp. 21-38

Abstract

Background
The pathophysiology of the acute phase of unstable angina (UA) is complex and the exact role of the alterations of hemostatic parameters during this period is not yet known .

Objectives

1)Assessment of variations of hemostatic and inflammatory parameters, reactive protein C (RPC) and troponin T (TnT) within 24 hs of CCU admission for unstable angina; 2) correlation of these variations with clinical outcome.

Methods
Ninety UA pts in 8 centers were included and blood samples were drawn at admission (a), 8, 16 and 24 hs and were analysed centrally. Blood levels of RCP, TnT, tPA, plasminogen activator inhibitor (PAI), complex tPA-PAI, D Dymer (DD), thrombin-antithrombin III (TAT) and fibrinogen (F) were determined. Events (Ev) were defined as: recurrent or refractory angina, acute myocardial infarction (AMI), death or urgent revascularization in the first week.

Results

Twenty five pts had Ev (27.8%) . Analysis of hemostatic parameters : by Cox logistic regression, Ev were related to PAIa**, 8 hs** and 16 hs; TnT 8 hs* and 16 hs* and tPA 8 hs* . AMI occurred in 5 pts and was associated with TnTa***, RPCa* and tPA-PAIa*. * : p < 0 .05; ** p< 0 .02; *** p < 0 .01. Analysis according to high or normal levels : high TnT levels were defined as 0.1 ng/ml and for the rest of parameters : a) mean plus two standard deviations with respect to 10 controls, or b) when an association with Ev was seen, the cut-off point determined by ROC curves . A significant association with Ev was seen for RPCa and DDa (odds 3 .6,1 .2-11 and 3.1, 1 .1-9 respectively) . At 16 hs an association of Ev with TnT (odds 3 .5,1-10) and tPA-PAI (odds 2.8, 1-8) was also observed.

Conclusions

Pathophysiology : blood markers of altered fibrynolitic activity, activated coagulation, minimal myocardial injury and inflammation are frequently observed in the acute phase of unstable angina .
Clinics: given the association of these biochemical alterations to worse outcome, analysis of hemostatic parameters may be a useful tool for risk assessment and management in unstable angina .