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.