High-sensitivity troponin T as a diagnostic tool for acute coronary syndrome in the real world: an observational study.

BACKGROUND: The 2011 European Society of Cardiology guidelines state that acute coronary syndrome (ACS) may be excluded with a rapid 3 h high-sensitivity troponin T (HsTnT) sampling protocol. We aimed to evaluate the diagnostic and prognostic performance of HsTnT in patients with chest pain admitted with possible ACS in routine care. METHODS: A total of 773 consecutive patients admitted for in-hospital care for chest pain suspicious of ACS were included retrospectively. HsTnT values at admission and at 3-4 and 6-7 h were analysed for diagnostic performance. In addition, prognostic performance towards a combined 60-day endpoint of ACS, nonelective revascularization or death of all causes was studied. RESULTS: Twenty-three per cent of the patients had ACS during the hospital stay and 1.6% had an endpoint after discharge but within 60 days. The sensitivity of HsTnT for ACS at admission, 3-4 and 6-7 h was only 68, 79 and 81%, respectively. Sensitivity and negative predictive value for acute myocardial infarction alone were 80 and 93% on admission and 97 and 99% at 3-4 h. Among patients aged 75 years and older, 63% had a positive HsTnT on admission, but only 39% of these had an ACS during hospital stay. CONCLUSION: Our data confirm that prolonged testing with HsTnT after 3-4 h does not improve diagnostic performance for ACS. However, although sensitivity for acute myocardial infarction was very good, sensitivity for ACS was insufficient to rule out ACS even at 6-7 h. Less than half of all recorded positive HsTnT were true positives. On the basis of these results, we find it unlikely that HsTnT has improved the diagnosis of ACS in the emergency care setting.