title: Incremental value of high-sensitivity cardiac troponin T for risk prediction in patients with suspected acute myocardial infarction.
abstract: BACKGROUND
  High-sensitivity cardiac troponin assays have better analytical precision and sensitivity than earlier-generation assays when measuring cardiac troponin at low concentrations. We evaluated whether use of a high-sensitivity assay could further improve risk stratification compared with a standard cardiac troponin assay.
  
  
  METHODS
  We enrolled consecutive patients presenting with acute chest pain, 30% of whom were diagnosed with acute coronary syndrome. Blood samples were drawn at the time of presentation. We measured cardiac troponin T with a standard fourth-generation assay (cTnT) and a high-sensitivity assay (hs-cTnT) (both Roche Diagnostics) and followed the patients for 24 months.
  
  
  RESULTS
  Of the 1159 patients, 76 died and 42 developed an acute myocardial infarction (AMI). Prognostic accuracy of hs-cTnT for death was significantly higher [area under ROC curve (AUC) 0.79, 95% CI 0.74-0.84] than that of cTnT (AUC 0.69, 95% CI 0.62-0.76; P < 0.001). After adjustment for Thrombolysis in Myocardial Infarction (TIMI) risk score (that included the cTnT assay result), hs-cTnT above the 99th percentile (0.014 μg/L) was associated with a hazard ratio for death of 2.60 (95% CI 1.42-4.74). Addition of hs-cTnT to the risk score improved the reclassification of patients (net reclassification improvement 0.91; 95% CI 0.67-1.14; P < 0.001). Subgroup analyses showed that this effect resulted from the better classification of patients without AMI at time of testing. hs-cTnT outperformed cTnT in the prediction of AMI during follow-up (P=0.02), but was not independently predictive for this endpoint.
  
  
  CONCLUSIONS
  Concentrations of hs-cTnT >0.014 μg/L improve the prediction of death but not subsequent AMI in unselected patients presenting with acute chest pain.
authors.affiliation: Department of Internal Medicine, University Hospital Basel, Switzerland.
authors.forename: Willibald
authors.initials: W
authors.lastname: Hochholzer
authors.forename: Tobias
authors.initials: T
authors.lastname: Reichlin
authors.forename: Raphael
authors.initials: R
authors.lastname: Twerenbold
authors.forename: Claudia
authors.initials: C
authors.lastname: Stelzig
authors.forename: Kirsten
authors.initials: K
authors.lastname: Hochholzer
authors.forename: Julia
authors.initials: J
authors.lastname: Meissner
authors.forename: Philip
authors.initials: P
authors.lastname: Haaf
authors.forename: Nora
authors.initials: N
authors.lastname: Schaub
authors.forename: Stephan
authors.initials: S
authors.lastname: Steuer
authors.forename: Stefano
authors.initials: S
authors.lastname: Bassetti
authors.forename: Miriam
authors.initials: M
authors.lastname: Reiter
authors.forename: Kathrin
authors.initials: K
authors.lastname: Roost
authors.forename: Heike
authors.initials: H
authors.lastname: Freidank
authors.forename: Katrin
authors.initials: K
authors.lastname: Winkler
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000175:diagnosis / Q000401:mortality; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000401:mortality; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T