title: Reliable exclusion of acute coronary syndrome among hospitalized patients with elevated troponin.
abstract: BACKGROUND
  Elevated cardiac troponin I (cTnI) occurs in acute coronary syndrome (ACS) as well as various scenarios not associated with ACS.
  
  
  OBJECTIVE
  Simple clinical criteria can reliably exclude ACS among hospitalized patients with elevated cTnI.
  
  
  METHODS
  Records for patients hospitalized from January to April 2011 with elevated cTnI (>0.29 ng/dL) and an available echocardiogram were retrospectively reviewed. Patients with ST-segment elevation myocardial infarction were excluded. Based on available clinical data, patients were classified as having ACS or elevation of cTnI unrelated to ACS (non-ACS). Median follow-up was 365 days.
  
  
  RESULTS
  Of 265 records meeting inclusion criteria, 82 (31%) had ACS and 183 (69%) had non-ACS. In multivariable analysis, odds ratios for non-ACS were 7.6 (95% confidence interval [CI]: 3.8-15.3) for peak cTnI <2 ng/dL, 6.3 (95% CI: 3.1-13.0) for absent wall-motion abnormality, and 4.4 (95% CI: 2.2-8.6) for no prior coronary artery disease history. The area under the receiver operating curve for amodel using these 3 variables was 0.86, with a 98% negative predictive value for excluding ACS. Patients who met these 3 criteria had no ACS-related deaths over 1-year follow-up.
  
  
  CONCLUSIONS
  Hospitalized patients with peak Tn level<2 ng/dL, no prior history of coronary artery disease, and no new echocardiographic wall-motion abnormality appear to have a very low likelihood of ACS. Prospective validation of these results is needed to determine whether additional diagnostic testing could be safely avoided in hospitalized patients meeting these simple clinical criteria.
authors.affiliation: Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
authors.forename: Melinda B
authors.initials: MB
authors.lastname: Davis
authors.forename: Asher
authors.initials: A
authors.lastname: Shafton
authors.forename: Aken
authors.initials: A
authors.lastname: Desai
authors.forename: David
authors.initials: D
authors.lastname: Childers
authors.forename: David S
authors.initials: DS
authors.lastname: Bach
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000175:diagnosis* / Q000000981:diagnostic imaging; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D019210:Troponin I / Q000097:blood*; D014463:Ultrasonography; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D019210:Troponin I