title: Sensitive troponin assay predicts outcome in syncope.
abstract: OBJECTIVE
  To assess whether plasma troponin concentration measured by a sensitive assay can predict 1-month and 1-year serious outcome, or all-cause death in patients presenting with syncope to the emergency department (ED).
  
  
  METHODS
  Prospective cohort study of admitted adult patients presenting to the ED after an episode of syncope who had plasma troponin measured 12 h after syncope using the ARCHITECT STAT sensitive troponin I assay (Abbott Diagnostics). Primary endpoints were the composite endpoint of serious outcome or all-cause death at 1 month and 1 year.
  
  
  RESULTS
  Between 1 March 2007 and 22 July 2008, 338 of 528 patients admitted from the ED with syncope had plasma troponin concentrations determined. Troponin concentrations were above the limit of detection in 261 (77%) patients. Patients numbering 120 (36%) had a troponin concentration ≥0.03 ng/ml (99th percentile of normal reference population), and 66 (20%) had concentrations ≥0.05 ng/ml (local diagnostic threshold for myocardial infarction). The proportion of patients with a composite serious outcome increased across patients stratified into quintiles based on peak troponin concentration at 1 month (0%, 9%, 13%, 26%, 70%) and at 1 year (10%, 22%, 26%, 52%, 85%).
  
  
  CONCLUSIONS
  The majority of patients admitted from the ED with syncope have detectable plasma troponin concentrations. Peak troponin concentration was associated with increasing risk of serious outcome and death, and this risk increases with higher troponin concentrations. Troponin may have a future role in the risk stratification of patients with syncope.
authors.affiliation: Emergency Medicine Research Group Edinburgh, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA, UK. mattreed1@hotmail.com
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Reed
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Mills
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Weir
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D004635:Emergency Medicine / Q000379:methods; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012606:Scotland; D012680:Sensitivity and Specificity; D013575:Syncope / Q000097:blood* / Q000401:mortality; D014336:Troponin / Q000097:blood*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D014336:Troponin