High sensitivity troponin T provides useful prognostic information in non-acute chest pain

To evaluate the prognostic value of high-sensitivity troponin T (hs-cTnT) in patients who present to General Practitioners (GPs) with non-acute chest pain.

A total of 625 patients who were referred by their GPs to a regional Rapid Access Chest Pain Clinic in Tayside, Scotland were consented and recruited. Diamond-Forrester pretest probability of coronary artery disease (CAD) was used to select patients with intermediate and high-pretest probability. Hs-cTnT and B-type Natriuretic Peptide (BNP) were measured and final diagnosis recorded. Twelve-month follow-up for cardiac events and hospital admission data was collected. Sensitivity, specificity, positive predictive value and negative predictive value (NPV), for both prognosis and diagnosis, were produced using various pre-specified cut-off values for hs-cTnT and BNP.

A total of 579 patients were included in the final analysis. Of these, 477 had intermediate/high-pretest probability of CAD. A total of 431 (90.4%) of patients had a hs-cTnT ≤14 ng/l. In this study, hs-cTnT of 14 ng/l was the best cut-off for ruling out if a patient would have an admission for cardiac chest pain in the following 12 months (specificity 90%, NPV 91.4%). It performed well as a predictor of a subsequent negative diagnosis of cardiac chest pain with a specificity of 92.4% and NPV of 83.5%.

Hs-cTnT, at the same level currently used in clinical practice as a diagnostic cut-off for myocardial infarction and acute coronary syndromes, is also a clinically-meaningful indicator for further 12-month cardiac chest pain hospital admissions in patients with non-acute chest pain referred to chest pain clinics by GPs.