Prognostic value of sensitive troponin T in patients with stable and unstable angina and undetectable conventional troponin

Background High-sensitivity cardiac troponin assays enable the measurement of cardiac troponin concentrations in the majority of patients with coronary artery disease. The objective of this study was to investigate the prognostic value of sensitive cardiac troponin in patients with stable and unstable angina presenting with undetectable levels of conventional troponin. Methods This study included 1,057 patients with stable (808 patients) or unstable (249 patients) angina who presented with undetectable conventional cardiac troponin T and underwent coronary artery revascularization. The cardiac troponin T was measured with conventional and high-sensitivity assays, in parallel, using the same plasma sample. The primary end point was 4-year mortality. Results The total sensitive troponin T level (median [interquartile range]) was 0.008 (0.005-0.014) mu g/L. Variables independently associated with an elevated level of sensitive troponin T were elderly age, male sex, higher body mass index, presence of diabetes, unstable angina, increased New York Heart Association class, reduced left ventricular ejection fraction, elevated level of N-terminal pro-brain natriuretic peptide, reduced glomerular filtration rate, and elevated level of C-reactive protein. During the follow-up period, there were 83 deaths. The sensitive troponin T level was an independent predictor of 4-year mortality (adjusted hazard ratio = 1.47 with 95% CI 1.17-1.84, P < .001 for each unit increase in the natural logarithm of the sensitive troponin T). Conclusions The elevated levels of sensitive cardiac troponin T in patients with stable or unstable angina presenting with undetectable conventional cardiac troponin T are significantly associated with reduced survival. (Am Heart J 2011;161:68-75.)