title: Early rule-out and rule-in of myocardial infarction using sensitive cardiac Troponin I.
abstract: BACKGROUND
  It is currently unknown, whether and to what extent sensitive cardiac troponin (s-cTn) allows shortening of the time required for safe rule-out and rule-in of acute myocardial infarction (AMI).
  
  
  METHODS
  We aimed to develop and validate early rule-out and rule-in algorithms for AMI using a thoroughly-examined and commonly used s-cTnI assay in a prospective multicenter study including 2173 patients presenting to the emergency department with suspected AMI. S-cTnI was measured in a blinded fashion at 0 h, 1 h, and 2 h. The final diagnosis was centrally adjudicated by two independent cardiologists. In the derivation cohort (n = 1496), we developed 1h- and 2h-algorithms assigning patients to "rule-out", "rule-in", or "observe". The algorithms were then prospectively validated in the validation cohort (n = 677).
  
  
  RESULTS
  AMI was the adjudicated diagnosis in 17% of patients. After applying the s-cTnI 1h-algorithm developed in the derivation cohort to the validation cohort, 65% of patients were classified as "rule-out", 12% as "rule-in", and 23% to "observe". The negative predictive value for AMI in the "rule-out" group was 98.6% (95% CI, 96.9-99.5), the positive predictive value for AMI in the "rule-in" group 76.3% (95% CI, 65.4-85.1). Overall, 30-day mortality was 0.2% in the "rule-out" group, 1.0% in the "observe" group, and 3.0% in the "rule-in" group. Similar results were obtained for the 2h-algorithm.
  
  
  CONCLUSIONS
  When used in conjunction with other clinical information including the ECG, a simple algorithm incorporating s-cTnI values at presentation and after 1h (or 2h) will allow safe rule-out and accurate rule-in of AMI in the majority of patients.
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland; Department of Internal Medicine, Kantonsspital Olten, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Druey
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Karin
authors.initials: K
authors.lastname: Wildi
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Raphael
authors.initials: R
authors.lastname: Twerenbold
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Cédric
authors.initials: C
authors.lastname: Jaeger
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Tobias
authors.initials: T
authors.lastname: Reichlin
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Philip
authors.initials: P
authors.lastname: Haaf
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland; Servicio de Urgencias y Pneumologia, CIBERES ISC III, Hospital del Mar - Institut Municipal d'Investigació Mèdica, Barcelona, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Rubini Gimenez
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Puelacher
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Max
authors.initials: M
authors.lastname: Wagener
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Milos
authors.initials: M
authors.lastname: Radosavac
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Ursina
authors.initials: U
authors.lastname: Honegger
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Carmela
authors.initials: C
authors.lastname: Schumacher
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Valentina
authors.initials: V
authors.lastname: Delfine
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Philip
authors.initials: P
authors.lastname: Kreutzinger
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Herrmann
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Zoraida
authors.initials: Z
authors.lastname: Moreno Weidmann
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Lian
authors.initials: L
authors.lastname: Krivoshei
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Freese
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Claudia
authors.initials: C
authors.lastname: Stelzig
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Cyril
authors.initials: C
authors.lastname: Isenschmid
authors.affiliation: Department of Internal Medicine, Kantonsspital Olten, Switzerland.
authors.forename: Stefano
authors.initials: S
authors.lastname: Bassetti
authors.affiliation: Laboratory Medicine, University Hospital Basel, Switzerland.
authors.forename: Katharina
authors.initials: K
authors.lastname: Rentsch
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Osswald
authors.affiliation: Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, Switzerland. Electronic address: Christian.Mueller@usb.ch.
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
mesh_terms: D000368:Aged; D000465:Algorithms; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D042241:Early Diagnosis; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D061665:Time-to-Treatment / Q000592:standards / Q000706:statistics & numerical data; D019210:Troponin I / Q000032:analysis / Q000097:blood
chemical_list: D015415:Biomarkers; D019210:Troponin I
keywords: Acute myocardial infarction; Algorithm; Rule-in; Rule-out; cTnI