title: A multicenter comparison of established and emerging cardiac biomarkers for the diagnostic evaluation of chest pain in the emergency department.
abstract: BACKGROUND
  The aim of this study is to assess the role of novel biomarkers for the diagnostic evaluation of acute coronary syndrome (ACS).
  
  
  METHODS
  Among 318 patients presenting to an emergency department with acute chest discomfort, we evaluated the diagnostic value of 5 candidate biomarkers (amino terminal pro-B-type natriuretic peptide [NT-proBNP], ischemia modified albumin, heart fatty acid binding protein, high-sensitivity troponin I [hsTnI], and unbound free fatty acids [FFAu]) for detecting ACS, comparing their results with that of conventional troponin T (cTnT).
  
  
  RESULTS
  Sixty-two subjects (19.5%) had ACS. The sensitivity and negative predictive values of NT-proBNP (73%, 90%) and hsTnI (57%, 89%) were higher than that of cTnT (22%, 84%). Unbound free fatty acids had the highest overall combination of sensitivity (75%), specificity (72%), and negative predictive values (92%) of all the markers examined. A significant increase in the C-statistic for cTnT resulted from the addition of results for NT-proBNP (change 0.09, P = .001), hsTnI (change 0.13, P < .001), and FFAu (change 0.15, P < .001). In integrated discrimination improvement and net reclassification improvement analyses, NT-proBNP, hsTnI, and FFAu added significant diagnostic information to cTnT; when changing the diagnostic criterion standard for ACS to hsTnI, FFAu still added significant reclassification for both events and nonevents. In serial sampling (n = 180), FFAu added important reclassification information to hsTnI.
  
  
  CONCLUSIONS
  Among emergency department patients with symptoms suggestive of ACS, neither ischemia modified albumin nor heart fatty acid binding protein detected or excluded ACS, whereas NT-proBNP, hsTnI, or FFAu added diagnostic information to cTnT. In the context of hsTnI results, FFAu measurement significantly reclassified both false negatives and false positives at baseline and in serial samples.
authors.affiliation: Division of Cardiology, Massachusetts General Hospital, Boston, 02114, USA.
authors.forename: Anju
authors.initials: A
authors.lastname: Bhardwaj
authors.forename: Quynh A
authors.initials: QA
authors.lastname: Truong
authors.forename: W Frank
authors.initials: WF
authors.lastname: Peacock
authors.forename: Kiang-Teck J
authors.initials: KT
authors.lastname: Yeo
authors.forename: Alan
authors.initials: A
authors.lastname: Storrow
authors.forename: Stephen
authors.initials: S
authors.lastname: Thomas
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Curtis
authors.forename: Robert S
authors.initials: RS
authors.lastname: Foote
authors.forename: Hong K
authors.initials: HK
authors.lastname: Lee
authors.forename: Karen F
authors.initials: KF
authors.lastname: Miller
authors.forename: James L
authors.initials: JL
authors.lastname: Januzzi
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D000418:Albumins / Q000378:metabolism; D015415:Biomarkers / Q000097:blood*; D002637:Chest Pain / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D004636:Emergency Service, Hospital; D050556:Fatty Acid-Binding Proteins / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011237:Predictive Value of Tests; D011379:Prognosis; D011498:Protein Precursors; D015203:Reproducibility of Results; D020107:Troponin T / Q000097:blood
chemical_list: D000418:Albumins; D015415:Biomarkers; D050556:Fatty Acid-Binding Proteins; D005230:Fatty Acids, Nonesterified; D010446:Peptide Fragments; D011498:Protein Precursors; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain