title: Combining presentation high-sensitivity cardiac troponin I and glucose measurements to rule-out an acute myocardial infarction in patients presenting to emergency department with chest pain.
abstract: OBJECTIVE
  The use of high sensitivity troponin (hs-Tn) may enable early rule out of acute myocardial infarction (AMI) for patients presenting to the emergency department (ED) with chest pain. This study evaluated two approaches to the early rule out of AMI; a combination of a presentation hs-Tn <4ng/L and normal glucose at presentation (dual testing) and a presentation hs-Tn troponin below the limit of detection (LoD).
  
  
  METHODS
  We utilised prospectively collected data on adult patients presenting with suspected ACS in two EDs in Australia and New Zealand. Blood samples were taken on presentation and tested for glucose and high sensitivity troponin I. The primary endpoint was index AMI and the secondary endpoint was 30-day acute coronary syndrome (ACS). Sensitivity, specificity, positive and negative predictive values were used to assess the diagnostic accuracy of the dual testing and LoD approaches.
  
  
  RESULTS
  Of the 1412 participants, 182 (12.9%) had index AMI. The LoD and the dual testing approach were 100% sensitive for index AMI. The specificity of the dual testing approach (25.2%) was slightly higher than that of the LoD (20.4%). Sensitivity for ACS was similar for the two approaches (96.5% for dual testing and 98.1% for the LoD).
  
  
  CONCLUSIONS
  The dual testing and LoD approach identified all patients with index AMI and could be used to reduce the proportion of patients requiring lengthy assessment and inpatient admission. Further investigation is still required to rule out unstable angina pectoris in patients identified as low risk.
authors.affiliation: Department of Emergency Medicine, Royal Brisbane and Women's Hospital, Australia School of Medicine, The University of Queensland, Australia School of Public Health, Queensland University of Technology, Australia. Electronic address: jaimi.greenslade@health.qld.gov.au.
authors.forename: J H
authors.initials: JH
authors.lastname: Greenslade
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Kavsak
authors.affiliation: Department of Cardiology, Royal Brisbane and Women's Hospital, Australia School of Medicine, The University of Queensland, Australia School of Public Health, Queensland University of Technology Australia, Australia.
authors.forename: W
authors.initials: W
authors.lastname: Parsonage
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Shortt
authors.affiliation: Department of Emergency Medicine, Christchurch Hospital, New Zealand.
authors.forename: M
authors.initials: M
authors.lastname: Than
authors.affiliation: Emergency Care Foundation, Christchurch Hospital, New Zealand.
authors.forename: J W
authors.initials: JW
authors.lastname: Pickering
authors.affiliation: Department of Cardiology, Christchurch Hospital, New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Aldous
authors.affiliation: Department of Emergency Medicine, Royal Brisbane and Women's Hospital, Australia School of Medicine, The University of Queensland, Australia School of Public Health, Queensland University of Technology, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Cullen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001681:Biological Assay / Q000379:methods / Q000592:standards*; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000097:blood* / Q000175:diagnosis; D015331:Cohort Studies; D004636:Emergency Service, Hospital / Q000592:standards*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000175:diagnosis; D011446:Prospective Studies; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I; D005947:Glucose
keywords: Acute coronary syndrome; Acute myocardial infarction; High sensitivity troponin