title: Comparison of high sensitivity troponin T and I assays in the diagnosis of non-ST elevation acute myocardial infarction in emergency patients with chest pain.
abstract: OBJECTIVE
  Concentrations of troponin measured with high sensitivity troponin assays are raised in a number of emergency department (ED) patients; however many are not diagnosed with acute myocardial infarction (AMI). Clinical comparisons between the early use (2h after presentation) of high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) assays for the diagnosis of AMI have not been reported.
  
  
  METHODS
  Early (0 h and 2 h) hs-cTnT and hs-cTnI assay results in 1571 ED patients with potential acute coronary syndrome (ACS) without ST elevation on electrocardiograph (ECG) were evaluated. The primary outcome was diagnosis of index AMI adjudicated by cardiologists using the local cTnI assay results taken ≥6 h after presentation, ECGs and clinical information. Stored samples were later analysed with hs-cTnT and hs-cTnI assays.
  
  
  RESULTS
  The ROC analysis for AMI (204 patients; 13.0%) for hs-cTnT and hs-cTnI after 2h was 0.95 (95% CI: 0.94-0.97) and 0.98 (95% CI: 0.97-0.99) respectively. The sensitivity, specificity, PLR, and NLR of hs-cTnT and hs-cTnI for AMI after 2h were 94.1% (95% CI: 90.0-96.6) and 95.6% (95% CI: 91.8-97.7), 79.0% (95% CI: 76.8-81.1) and 92.5% (95% CI: 90.9-93.7), 4.48 (95% CI: 4.02-5.00) and 12.86 (95% CI: 10.51-15.31), and 0.07 (95% CI: 0.04-0.13) and 0.05 (95% CI:0.03-0.09) respectively.
  
  
  CONCLUSIONS
  Exclusion of AMI 2h after presentation in emergency patients with possible ACS can be achieved using hs-cTnT or hs-cTnI assays. Significant differences in specificity of these assays are relevant and if using the hs-cTnT assay, further clinical assessment in a larger proportion of patients would be required.
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; Queensland University of Technology, Brisbane, QLD, Australia.
authors: Louise
authors: L
authors: Cullen
authors: Christchurch Hospital, Christchurch, New Zealand.
authors: Sally
authors: S
authors: Aldous
authors: Christchurch Hospital, Christchurch, New Zealand.
authors: Martin
authors: M
authors: Than
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; Queensland University of Technology, Brisbane, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: Jaimi H
authors: JH
authors: Greenslade
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia.
authors: Jillian R
authors: JR
authors: Tate
authors: Christchurch Hospital, Christchurch, New Zealand.
authors: Peter M
authors: PM
authors: George
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: Christopher J
authors: CJ
authors: Hammett
authors: Christchurch Heart Institute, University of Otago, Christchurch, New Zealand; Cardiovascular Research Institute, National University Heart Centre, Singapore.
authors: A Mark
authors: AM
authors: Richards
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia.
authors: Jacobus P J
authors: JP
authors: Ungerer
authors: Christchurch Heart Institute, University of Otago, Christchurch, New Zealand.
authors: Richard W
authors: RW
authors: Troughton
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: Anthony F T
authors: AF
authors: Brown
authors: The University of Queensland, Brisbane, QLD, Australia.
authors: Dylan F
authors: DF
authors: Flaws
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: Arvin
authors: A
authors: Lamanna
authors: Christchurch Heart Institute, University of Otago, Christchurch, New Zealand.
authors: Christopher J
authors: CJ
authors: Pemberton
authors: Christchurch Hospital, Christchurch, New Zealand.
authors: Christopher
authors: C
authors: Florkowski
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia.
authors: Carel J
authors: CJ
authors: Pretorius
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: Kevin
authors: K
authors: Chu
authors: Royal Brisbane and Women's Hospital, Herston, QLD, Australia; The University of Queensland, Brisbane, QLD, Australia.
authors: William A
authors: WA
authors: Parsonage
mesh_terms: D000328:Adult; D000368:Aged; D001315:Australia; D002637:Chest Pain / Q000097:blood / Q000150:complications*; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D009520:New Zealand; D012372:ROC Curve; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
chemical_list: D019210:Troponin I; D020107:Troponin T
keywords: Acute myocardial infarction; Chest pain; Diagnostic accuracy; Emergency; High sensitivity troponin