RELATION BETWEEN TROPONIN-T AND THE RISK OF SUBSEQUENT CARDIAC EVENTSIN UNSTABLE CORONARY-ARTERY DISEASE

Background Early risk assessment is important in patients with unstabl e coronary artery disease, ie, unstable angina or non-Q-wave myocardia l infarction. Some previous small studies have indicated that patients with unstable angina and elevation of troponin T (tn-T) have worse sh ort-term and longterm prognoses. In this study, the prognostic value o f tn-T was evaluated and compared with other early available risk indi cators. Methods and Results Nine hundred seventy-six patients particip ating in a randomized study of low-molecular-weight heparin in unstabl e coronary artery disease were followed for 5 months after the index e pisode. The risk of cardiac events increased with increasing maximal l evels of tn-T obtained in the initial 24 hours. The lowest quintile (< 0.06 mu g/L) constituted a low-risk group, the second quintile (0.06 t o 0.18 mu g/L) an intermediate-risk group, and the three highest quint iles (greater than or equal to 0.18 mu g/L) a high-risk group, with 4. 3%, 10.5%, and 16.1% risk of either myocardial infarction or cardiac d eath, respectively. Troponin T level was identified together with age, hypertension, number of antianginal drugs, and ECG changes at rest as independent prognostic variables for myocardial infarction or cardiac death in a multivariate analysis. The prognostic value of tn-T was in dependent of the classification of index event into unstable angina or myocardial infarction. Conclusions Troponin T determination is an ine xpensive and widely applicable method for early risk assessment in pat ients with unstable coronary artery disease. The maximum tn-T value ob tained during the first 24 hours provides independent and important pr ognostic information.