Risk stratification in unstable coronary artery disease: Additive value of troponin T determinations and pre-discharge exercise tests

Abstract
In 963 patients, participating in a randomized study of low molecular weight heparin in unstable coronary artery disease and followed for 5 months, troponin T was determined. In the 766 patients with a pre-discharge exercise test both troponin T level and exercise test response were independent predictors of prognosis. Cardiac death or myocardial infarction occurred in 5, 9 and 13% of the patients with a maximal troponin T level of −1 (n=437), respectively. Based on exercise tolerance and occurrence of ST depression, patients with a low (n=361), intermediate (n=325) and high risk (n=80) exercise test response were identified. In these, death or myocardial infarction occurred in 5, 13 and 29%, respectively. The combination of troponin T and the exercise test response allowed an even better categorization into low (n=84), intermediate (n=406) and high (n=276) risk groups with 1, 7 and 20% death or myocardial infarction, respectively. Among those 197 patients unable to perform an exercise test the incidence was 3, 16 and 27% in patients with troponin T −1, respectively. Thus, troponin T determinations and pre-discharge exercise tests alone and combined are valuable for risk assessment in unstable coronary artery disease.