title: Serial Sampling of High-Sensitivity Cardiac Troponin T May Not Be Required for Prediction of Acute Myocardial Infarction Diagnosis in Chest Pain Patients with Highly Abnormal Concentrations at Presentation.
abstract: BACKGROUND
  Guidelines for diagnosing acute myocardial infarction (AMI) recommend adding kinetic changes to the initial cardiac troponin (cTn) blood concentration to improve AMI diagnosis. We hypothesized that kinetic changes may not be required in patients presenting with highly abnormal cTn.
  
  
  METHODS
  Patients presenting with suspected AMI to the emergency department were enrolled in a prospective diagnostic study. We assessed the positive predictive value (PPV) of initial high-sensitivity cardiac troponin T (hs-cTnT) blood concentrations alone and in combination with kinetic changes for AMI. Predefined relative changes (δ change of ≥20%) and absolute changes (Δ change ≥9.2 ng/L) within different time intervals (1 h, 2 h, and 4-14 h after presentation) were assessed. The final diagnosis was adjudicated by 2 independent cardiologists.
  
  
  RESULTS
  Among 1282 patients, 213 (16.6%) patients had a final diagnosis of AMI. For AMI prediction, PPVs increased from 48.8% for an initial hs-cTnT >14 ng/L to 87.2% for >60 ng/L, whereas PPVs remained unchanged for higher hs-cTnT concentrations at baseline (87.1% for both >80 ng/L and >100 ng/L). With addition of 20% relative Δ change, PPVs were not further improved in patients with baseline hs-cTnT >80 ng/L using the 1-h (84.0%) and 2-h (88.9%) intervals, and only minimally when extending the interval to 4-14 h (91.2% for >80 ng/L and 90.4% for >100 ng/L, respectively). Similar findings were observed when applying absolute changes.
  
  
  CONCLUSIONS
  In chest pain patients with highly abnormal hs-cTnT concentrations at presentation, subsequent blood draws may not be required, as they do not provide incremental diagnostic value for prediction of AMI diagnosis.
authors.affiliation: Department of Internal Medicine III, Cardiology, Angiology & Pulmonology, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Mueller-Hennessen
authors.affiliation: Cardiology & Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
authors.affiliation: Department of Internal Medicine III, Cardiology, Angiology & Pulmonology, Heidelberg University Hospital, Heidelberg, Germany; evangelos_giannitsis@med.uni-heidelberg.de.
authors.forename: Evangelos
authors.initials: E
authors.lastname: Giannitsis
authors.affiliation: Department of Internal Medicine III, Cardiology, Angiology & Pulmonology, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Biener
authors.affiliation: Department of Internal Medicine III, Cardiology, Angiology & Pulmonology, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Mehrshad
authors.initials: M
authors.lastname: Vafaie
authors.affiliation: Department of Medicine, University of Maryland School of Medicine, Baltimore, MD.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: deFilippi
authors.affiliation: Department of Emergency and Critical Care Medicine, Community Hospital and Paracelsus Medical University, Nuremberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Christ
authors.affiliation: Department of Clinical Biochemistry, Institut d'Investigacions Biomèdiques Sant Pau, Barcelona, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Ordóñez-Llanos
authors.affiliation: Department of Biomedical and Clinical Sciences "Luigi Sacco," University of Milan Medical School, Milan, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Panteghini
authors.affiliation: Department of Laboratory Medicine, University Hospital of Padova, Padua, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Plebani
authors.affiliation: Department of Acute Medicine, Cliniques Universitaires St-Luc and Université Catholique de Louvain, Brussels, Belgium.
authors.forename: Franck
authors.initials: F
authors.lastname: Verschuren
authors.affiliation: Department of Medicine, Karolinska Institutet, Huddinge and Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Dina
authors.initials: D
authors.lastname: Melki
authors.affiliation: Liverpool Hospital and University of New South Wales, Sydney, Australia.
authors.forename: John K
authors.initials: JK
authors.lastname: French
authors.affiliation: Department of Pathology, University of Maryland School of Medicine, Baltimore, MD.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Christenson
authors.affiliation: Central Manchester University Hospitals NHS Foundation Trust, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Body
authors.affiliation: Henry Ford Heart and Vascular Institute, Henry Ford Health System, Detroit, MI.
authors.forename: James
authors.initials: J
authors.lastname: McCord
authors.affiliation: Roche Diagnostics Germany, Penzberg, Germany.
authors.forename: Carina
authors.initials: C
authors.lastname: Dinkel
authors.affiliation: Department of Internal Medicine III, Cardiology, Angiology & Pulmonology, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Katus
authors.affiliation: Department of Medical Sciences and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden.
authors.forename: Bertil
authors.initials: B
authors.lastname: Lindahl
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D002637:Chest Pain / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis*; D011237:Predictive Value of Tests; D020107:Troponin T / Q000097:blood*
chemical_list: D020107:Troponin T