title: Early diagnosis of acute myocardial infarction in patients with pre-existing coronary artery disease using more sensitive cardiac troponin assays.
abstract: OBJECTIVE
  We sought to examine the diagnostic and prognostic utility of sensitive cardiac troponin (cTn) assays in patients with pre-existing coronary artery disease (CAD).
  
  
  RESULTS
  We conducted a multicentre study to examine the diagnostic accuracy of one high-sensitive and two sensitive cTn assays in 1098 consecutive patients presenting with symptoms suggestive of acute myocardial infarction (AMI), of whom 401 (37%) had pre-existing CAD. Measurements of Roche high-sensitive cTnT (hs-cTnT), Siemens cTnI-Ultra, Abbott-Architect cTnI and the standard assay (Roche cTnT) were performed in a blinded fashion. The final diagnosis was adjudicated by two independent cardiologists. Acute myocardial infarction was the final diagnosis in 19% of CAD patients. Among patients with diagnoses other than AMI, baseline cTn levels were elevated above the 99th percentile with Roche hs-cTnT in 40%, with Siemens TnI-Ultra in 15%, and Abbott-Architect cTnI in 13% of them. In patients with pre-existing CAD, the diagnostic accuracy at presentation, quantified by the area under the receiver operator characteristic curve (AUC), was significantly greater for the sensitive cTn assays compared with the standard assay (AUC for Roche hs-cTnT, 0.92; Siemens cTnI-Ultra, 0.94; and Abbott-Architect cTnI, 0.93 vs. AUC for the standard assay, 0.87; P < 0.01 for all comparisons). Elevated levels of cTn measured with the sensitive assays predicted mortality irrespective of pre-existing CAD, age, sex, and cardiovascular risk factors.
  
  
  CONCLUSIONS
  Sensitive cTn assays have high-diagnostic accuracy also in CAD patients. Mild elevations are common in non-AMI patients and test-specific optimal cut-off levels tend to be higher in CAD patients than in patients without history of CAD. Sensitive cTn assays also retain prognostic value. (ClinicalTrials.gov number, NCT00470587).
authors: Department of Internal Medicine,  University Hospital, Petersgraben 4, CH-4031 Basel,  Switzerland.
authors: Miriam
authors: M
authors: Reiter
authors: Raphael
authors: R
authors: Twerenbold
authors: Tobias
authors: T
authors: Reichlin
authors: Benjamin
authors: B
authors: Benz
authors: Philip
authors: P
authors: Haaf
authors: Julia
authors: J
authors: Meissner
authors: Willibald
authors: W
authors: Hochholzer
authors: Claudia
authors: C
authors: Stelzig
authors: Michael
authors: M
authors: Freese
authors: Corinna
authors: C
authors: Heinisch
authors: Cathrin
authors: C
authors: Balmelli
authors: Beatrice
authors: B
authors: Drexler
authors: Heike
authors: H
authors: Freidank
authors: Katrin
authors: K
authors: Winkler
authors: Isabel
authors: I
authors: Campodarve
authors: Joaquim
authors: J
authors: Gea
authors: Christian
authors: C
authors: Mueller
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D003324:Coronary Artery Disease / Q000150:complications*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis*; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T