Clinical InvestigationAcute Ischemic Heart DiseaseUsefulness of high-sensitivity troponin T for the evaluation of patients with acute chest pain and no or minimal myocardial damage

BackgroundAlthough high-sensitivity troponins allow early diagnosis of acute myocardial infarction, their role for identification of acute coronary syndrome in patients with normal conventional troponin remains unclear.Methods and resultsA total of 446 patients presenting to the emergency department with chest pain and normal troponin (common practice assays) in 2 serial samples were included. Both samples were also centrally analyzed for high-sensitivity troponin T (hs-TnT) (Roche Diagnostics, Basel, Switzerland). Detection (> 3 ng/L) and 99th percentile (≥ 14 ng/L) cutoffs of the maximum hs-TnT levels (hs-TnTmax) were considered. The end points were acute coronary syndrome diagnosis and the composite of in-hospital revascularization or 30-day cardiac events.ResultsAcute coronary syndrome was adjudicated to 84 patients (19%), and 62 (14%) had the composite end point. In univariate setting, hs-TnTmax > 3 ng/L exhibited high sensitivity (87% and 92%, respectively) and negative predictive value (93% and 97%) for both end points, whereas hs-TnTmax ≥ 14 ng/L provided high specificity (90% and 89%), although low positive predictive values (40% and 33%). After adjusting for clinical (pain characteristics and risk factors) and electrocardiographic data, there was a stepped increase of risk across hs-TnTmax categories (≤ 3, > 3 but < 14, and ≥ 14 ng/L) for both end points; however, the discriminative capacity added was marginal (integrated discrimination improvement of 2.6% and 3.5%, respectively).ConclusionsClinical and electrocardiographic data remain the most important tools for the evaluation of patients with chest pain and with no or minimal myocardial damage. The main contribution of hs-TnT is the high negative predictive value of undetectable levels (≤ 3 ng/L).