CAN C-REACTIVE PROTEIN OR TROPONIN-T AND TROPONIN-I PREDICT OUTCOME IN PATIENTS WITH INTRACTABLE UNSTABLE ANGINA

Objective-To determine whether a single blood test for the measurement of C reactive protein, or troponin I or T concentrations could be use d to stratify patients with intractable unstable angina awaiting trans fer for coronary angiography by correlating these values with coronary anatomy and transient myocardial ischaemia. Design-Prospective study. Setting-Tertiary cardiac unit. Patients-Ah patients admitted to their local hospital with ischaemic chest pain, uncontrolled by medical tre atment, in whom acute myocardial infarction had been excluded by seria l measurement of creatine kinase and lack of Q waves on EGG. Intervent ion-Coronary angiography and ST segment monitoring for 24 hours. Main outcome measures-Concentrations of C reactive protein, troponins T and I, coronary anatomy, presence of transient myocardial ischaemia. Resu lts-Median C reactive protein, troponin I, and troponin T concentratio ns were 17.1 mg/dl (4.8 to 203.9), 0.05 mu g/1 (0 to 7.8), and 0.0 mu g/1 (0 to 2.51), respectively. Seven patients (10%) had normal coronar ies and 14, 20, and 31 had one, two, or three vessel coronary disease, respectively. Nineteen (26%) had transient myocardial ischaemia, 33 ( 46%) had complex lesion morphology, and six (8%) had intracoronary thr ombus. Of the three markers, troponin T alone was higher in patients w ith multivessel disease (p < 0.05) and in those with transient myocard ial ischaemia (p < 0.05), but there was no significant relation betwee n C reactive protein, troponin T or I and lesion morphology or thrombu s. Conclusions-In patients transferred to a tertiary centre with intra ctable chest pain, C reactive protein and troponin I are not predictiv e of transient myocardial ischaemia or lesion morphology, both of whic h are surrogate markers of outcome. Troponin T is, however, raised in patients with multivessel disease or transient myocardial ischaemia. T hese serum protein assays cannot be used to stratify the risk of patie nts with unstable angina who are awaiting transfer to the tertiary cen tre.