Temporal Changes of Stable High-Sensitivity Cardiac Troponin T Levels and Prognosis

Background The prognostic implications of temporal change of previously stable high-sensitivity cardiac troponin concentrations are unknown. We investigated the prognosis associated with temporal changes of stable high-sensitivity cardiac troponin T (hs-cTnT) concentrations. Methods and Results All patients presenting with cardiac symptoms and ≥2 hs-cTnT measurements at the time of their first visit to 7 different emergency departments in Sweden between December 9, 2009, and December 31, 2016, were identified (n=66 159). We included all patients with stable hs-cTnT but no acute coronary syndrome diagnosis who had ≥1 hs-cTnT measured also at a second visit >30 days from the first visit. Hazard ratios (HRs) with 95% CIs were calculated for all-cause mortality and cardiovascular events according to temporal change of hs-cTnT between the visits, using patients without myocardial injury (<15 ng/L) at the first visit and persistently stable hs-cTnT at the second visit as the reference. Altogether, 12 869 patients were included, of whom 5191 (40%) had myocardial injury (hs-cTnT ≥15 ng/L). During a median follow-up of 2.3 (interquartile range, 1.4-3.7) years, 3271 (25%) patients died. In patients with myocardial injury and a temporal increase in hs-cTnT, the adjusted all-cause and cardiovascular mortality was 4- and 5-fold elevated (HR, 4.21; 95% CI, 3.55-5.00; and HR, 5.08; 95% CI, 3.73-6.92), and the adjusted risk of heart failure hospitalization almost 3-fold (HR, 2.77; 95% CI, 2.26-3.39). Conclusions Temporal change of previously stable hs-cTnT is associated with the risk of death and cardiovascular outcomes, with highest risks observed in patients with myocardial injury and increasing hs-cTnT.