title: Improved assay of cardiac troponin I is more sensitive than other assays of necrosis markers.
abstract: OBJECTIVE
  Highly sensitive and specific assays of cardiac troponins I and T are the preferred biomarkers in diagnosing myocardial infarction (MI). Assays of cardiac troponin I (cTnI) have been improved with the addition of antibodies against the cTnI molecule and may have increased sensitivity. We hypothesized that a cTnI assay with modern antibody configuration will exhibit equal or better sensitivity in the setting of acute MI compared to cTnT and other markers of myocardial necrosis.
  
  
  METHODS
  We investigated release kinetics of cTnI (Abbott ADV, Abbott Diagnostics), cTnT (Roche Diagnostics), CKMBmass, myoglobin and heart fatty acid binding protein (H-FABP) in 23 patients admitted with acute ST-segment elevation MI undergoing primary percutaneous coronary intervention. Calibrators for the Abbott ADV cTnI assay are traceable to the United States National Institute of Standards and Technology (NIST) reference material for cTnI. Eleven blood samples were drawn from each patient in the period from admission to 24 h. Biomarkers of necrosis showed marked increases in relative concentrations, especially within the first 2 h after admission.
  
  
  RESULTS
  From 30 min after admission onwards, cTnI exhibited significantly higher relative concentrations compared to cTnT, CKMBmass, Myoglobin and H-FABP (p<0.05).
  
  
  CONCLUSIONS
  The NIST standardized Abbott TnI ADV assay appears to be more sensitive than cTnT and other biomarkers in the early phase of MI.
authors.affiliation: Department of Cardiology, Aalborg Hospital, Aarhus University Hospital, Hobrovej 16-18, DK-9000 Denmark. sph@dadlnet.dk
authors.forename: S
authors.initials: S
authors.lastname: Hjortshøj
authors.forename: C
authors.initials: C
authors.lastname: Dethlefsen
authors.forename: S Risom
authors.initials: SR
authors.lastname: Kristensen
authors.forename: J
authors.initials: J
authors.lastname: Ravkilde
mesh_terms: D015415:Biomarkers / Q000097:blood*; D006801:Humans; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis; D009336:Necrosis; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I