title: Characterisation of a highly sensitive troponin I assay and its application to a cardio-healthy population.
abstract: BACKGROUND
  Abbott Diagnostics have developed a new highly sensitive troponin I (hs-TnI) assay. We have assessed its analytical characteristics and applied the assay to a population of apparently cardio-healthy persons.
  
  
  METHODS
  We assessed imprecision, bias compared to the previous generation assay, matrix effects, and interferences and applied the assay to an apparently healthy population, deriving the 99th percentile limit of the distribution of values in reference populations for men and women separately.
  
  
  RESULTS
  The dynamic range of the assay was ranged from 0.5-50,000 ng/L (pg/mL). The 10% CV was at a concentration of 3.9 ng/L, and the 20% CV was at a concentration of 1.8 ng/L. The new and current version of the TnI assay were highly correlated [slope: 0.98 (95%CI:0.88-1.07), y-intercept:1.20 (95%CI:-2.35-4.75) r²=0.99]. The 99th percentile limit of the distribution of values in a reference population was different for males and females: for males 14.0 ng/L and for females 11.1 ng/L and at these concentrations the assay CV was 5.0%. TnI was detectable in nearly all patient samples from the healthy reference population (98.6%).
  
  
  CONCLUSIONS
  This new hs-TnI assay is able to measure to an order of magnitude lower than the current generation TnI assay from the same manufacturer. With TnI being detectable in nearly all apparently healthy subject samples this suggests that TnI presence does not always indicate cardiomyocyte necrosis.
authors.affiliation: ACT Pathology, The Canberra Hospital, Canberra, ACT, Australia.
authors.forename: Gus
authors.initials: G
authors.lastname: Koerbin
authors.forename: Jill
authors.initials: J
authors.lastname: Tate
authors.forename: Julia M
authors.initials: JM
authors.lastname: Potter
authors.forename: Juleen
authors.initials: J
authors.lastname: Cavanaugh
authors.forename: Nicholas
authors.initials: N
authors.lastname: Glasgow
authors.forename: Peter E
authors.initials: PE
authors.lastname: Hickman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001774:Blood Chemical Analysis / Q000379:methods*; D005260:Female; D006262:Health; D006461:Hemolysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D019210:Troponin I / Q000097:blood*; D055815:Young Adult
chemical_list: D019210:Troponin I