title: The new high-sensitivity cardiac troponin T assay improves risk assessment in acute coronary syndromes.
abstract: BACKGROUND
  Cardiac troponins are currently the markers of choice for diagnosis of acute myocardial infarction and risk assessment in acute coronary syndrome (ACS). With the introduction of the new high-sensitivity cardiac troponin T (hs-cTnT) assay, it has become possible to measure cTnT even in healthy subjects. However, how the hs-cTnT assay compares with the old cTnT assay for risk assessment in ACS is still unknown.
  
  
  METHODS
  Cardiac troponin T levels were measured with the new hs-cTnT assay and the old third-generation cTnT assay in serum samples collected 48 hours after randomization in 1,452 randomly selected ACS patients enrolled in the GUSTO-IV trial. During 30 days of follow-up, deaths and myocardial infarctions were recorded. At 12 months, only all-cause mortality was collected.
  
  
  RESULTS
  The 16% of the patients that had levels higher than the 99th percentile cutoff for hs-cTnT but less than for cTnT had a similar 1-year mortality as the 60% that were positive for both assays (9.2% vs 10.7%, P = .52) and a higher 1-year mortality compared with the 24% that were negative for both assays (9.2% vs 2.6%, P = .001). For death or acute myocardial infarction at 30 days, the group that was positive only for hs-cTnT had an intermediate risk compared with the groups negative or positive for both assays (2.4%, 5.2%, and 8.7%; P < .001).
  
  
  CONCLUSIONS
  The new hs-cTnT assay, compared with the old cTnT assay, identified more patients with myocardial damage and who were at an increased risk for new cardiac events.
authors.affiliation: Department of Medical Sciences, Cardiology, and Uppsala Clinical Research Center, University of Uppsala, Uppsala, Sweden. bertil.lindahl@ucr.uu.se
authors.forename: Bertil
authors.initials: B
authors.lastname: Lindahl
authors.forename: Per
authors.initials: P
authors.lastname: Venge
authors.forename: Stefan
authors.initials: S
authors.lastname: James
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T; D003404:Creatinine