Adding historical high-sensitivity troponin T results to rule out acute myocardial infarction.

Abstract

The clinical usefulness of historical concentrations of high-sensitivity cardiac troponin T (hs-cTnT) is unknown. This study investigated the ability to rule out myocardial infarction (MI) with the use of historical hs-cTnT concentrations among patients with chest pain in the emergency department (ED). The derivation cohort consisted of patients presenting with chest pain to nine different EDs (n = 60 071), where we included those with ≥1 hs-cTnT analysed at the index visit and ≥1 hs-cTnT results prior to the visit. We developed an algorithm to rule out MI within 30 days with a pre-specified target negative predictive value (NPV) of ≥99.5%. The performance was then validated in a separate cohort of ED chest pain patients (n = 10 994). A historical hs-cTnT < 12 ng/L and a < 3 ng/L absolute change between the historical and the index visit hs-cTnT had the best performance and ruled out 24 862 (41%) patients in the derivation cohort. In the validation cohort, these criteria identified 4764 (43%) low-risk patients in whom 18 (0.4%) MIs within 30 days occurred, and had an NPV for MI of 99.6% (99.4-99.8), a sensitivity of 96.9% (95.2-.2), and an LR- of 0.11 (0.07-0.14). Combining a historical hs-cTnT with a single new hs-cTnT may safely rule out MI and thereby reduce the need for serial hs-cTnT measurements in ED patients with chest pain.