title: Usage of troponin in the real world: a lesson for the introduction of biochemical assays.
abstract: BACKGROUND
  Studies have demonstrated economic and clinical effectiveness using troponin as a risk stratification tool in chest pain patients. Those with a positive result are investigated invasively, whilst those with a negative result and ECG are promptly mobilized, facilitating discharge.
  
  
  OBJECTIVE
  To determine whether our use of troponin I (cTnI) in routine clinical practice conforms to ideal standards.
  
  
  METHODS
  Audit study.
  
  
  METHODS
  Data were collected from 93 laboratory request forms for cTnI measurement on 72 patients with matched available patient records.
  
  
  RESULTS
  Eighty requests had no information regarding timing of blood sample in relation to the clinical event; 39% gave no clinical indication. Only 71% of results were available within 12 h. An admission diagnosis of acute coronary syndrome (ACS) was made in 25%. Fifteen had typical cardiac chest pain with a negative cTnI: 6 of these had an exercise treadmill test before discharge. Nine had a positive cTnI, but only two had coronary angiography. Of patients with negative cTnI and possible ACS, 84% were in hospital for >4 days.
  
  
  CONCLUSIONS
  The introduction of troponin assays into widespread use requires careful assessment. cTnI requests and subsequent patient management remain below expected standards. Ideally, the laboratory should provide an accurate result within a reasonable time frame, while physicians need to request cTnI at a suitable time-point and use the result appropriately. Lessons from the introduction of cTnI measurement may be useful for the introduction of future new tests in other areas of cardiology and medicine.
authors.affiliation: Department of Cardiology, Charing Cross Hospital, London, UK. krajappan@hhnt.org
authors.forename: K
authors.initials: K
authors.lastname: Rajappan
authors.forename: E
authors.initials: E
authors.lastname: Murphy
authors.forename: V
authors.initials: V
authors.lastname: Amber
authors.forename: F
authors.initials: F
authors.lastname: Meakin
authors.forename: B
authors.initials: B
authors.lastname: Muller
authors.forename: K F
authors.initials: KF
authors.lastname: Fox
authors.forename: C S R
authors.initials: CS
authors.lastname: Baker
mesh_terms: D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000175:diagnosis*; D003327:Coronary Disease / Q000175:diagnosis*; D003937:Diagnosis, Differential; D006801:Humans; D011237:Predictive Value of Tests; D018570:Risk Assessment; D013577:Syndrome; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I