title: Necessity of hospitalization and stress testing in low risk chest pain patients.
abstract: BACKGROUND
  Copeptin is a marker of endogenous stress including early myocardial infarction(MI) and has value in early rule out of MI when used with cardiac troponin I(cTnI).
  
  
  OBJECTIVE
  The goal of this study was to demonstrate that patients with a normal electrocardiogram and cTnI<0.040μg/l and copeptin<14pmol/l at presentation and after 2 h may be candidates for early discharge with outpatient follow-up potentially including stress testing.
  
  
  METHODS
  This study uses data from the CHOPIN trial which enrolled 2071 patients with acute chest pain. Of those, 475 patients with normal electrocardiogram and normal cTnI(<0.040μg/l) and copeptin<14pmol/l at presentation and after 2 h were considered "low risk" and selected for further analysis.
  
  
  RESULTS
  None of the 475 "low risk" patients were diagnosed with MI during the 180day follow-up period (including presentation). The negative predictive value of this strategy was 100% (95% confidence interval(CI):99.2%-100.0%). Furthermore no one died during follow up. 287 (60.4%) patients in the low risk group were hospitalized. In the "low risk" group, the only difference in outcomes (MI, death, revascularization, cardiac rehospitalization) was those hospitalized underwent revascularization more often (6.3%[95%CI:3.8%-9.7%] versus 0.5%[95%CI:0.0%-2.9%], p=.002). The hospitalized patients were tested significantly more via stress testing or angiogram (68.6%[95%CI:62.9%-74.0%] vs 22.9%[95%CI:17.1%-29.6%], p<.001). Those tested had less cardiac rehospitalizations during follow-up (1.7% vs 5.1%, p=.040).
  
  
  CONCLUSIONS
  In conclusion, patients with a normal electrocardiogram, troponin and copeptin at presentation and after 2 h are at low risk for MI and death over 180days. These low risk patients may be candidates for early outpatient testing and cardiology follow-up thereby reducing hospitalization.
authors.affiliation: Department of Internal Medicine, University of California, San Diego, La Jolla, CA, United States. Electronic address: neil.beri1@gmail.com.
authors.forename: Neil
authors.initials: N
authors.lastname: Beri
authors.affiliation: Department of Internal Medicine, University of California, San Diego, La Jolla, CA, United States.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Marston
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of California, San Diego, La Jolla, California, United States.
authors.forename: Lori B
authors.initials: LB
authors.lastname: Daniels
authors.affiliation: Department of Emergency Medicine, Henry Ford Health System, Detroit, MI, United States.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Nowak
authors.affiliation: Department of Emergency Medicine, Stanford University, Palo Alto, CA, United States.
authors.forename: Donald
authors.initials: D
authors.lastname: Schreiber
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Mayo Clinic, Rochester, MN, United States.
authors.forename: Allan
authors.initials: A
authors.lastname: Jaffe
authors.affiliation: Department of Emergency Medicine, University of Texas Southwestern, Dallas, TX, United States.
authors.forename: Deborah B
authors.initials: DB
authors.lastname: Diercks
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of California, San Diego, La Jolla, California, United States.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Wettersten
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Maryland, Baltimore, MD, United States.
authors.forename: Christopher
authors.initials: C
authors.lastname: DeFilippi
authors.affiliation: Department of Emergency Medicine, Baylor College of Medicine, Houston, TX, United States.
authors.forename: W Frank
authors.initials: WF
authors.lastname: Peacock
authors.affiliation: Department of Emergency Medicine, Duke University, Durham, NC, United States.
authors.forename: Alexander T
authors.initials: AT
authors.lastname: Limkakeng
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Veterans Affairs Medical Center, Minneapolis, MN, United States.
authors.forename: Inder
authors.initials: I
authors.lastname: Anand
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Henry Ford Health System, Detroit, MI, United States.
authors.forename: James
authors.initials: J
authors.lastname: McCord
authors.affiliation: Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA, United States.
authors.forename: Judd E
authors.initials: JE
authors.lastname: Hollander
authors.affiliation: Department of Pathology and Laboratory Medicine, University of California, San Francisco, CA, United States.
authors.forename: Alan H B
authors.initials: AHB
authors.lastname: Wu
authors.affiliation: Department of Pathology, Hennepin County Medical Center and University of Minnesota, Minneapolis, United States.
authors.forename: Fred S
authors.initials: FS
authors.lastname: Apple
authors.affiliation: Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA, United States.
authors.forename: John T
authors.initials: JT
authors.lastname: Nagurney
authors.affiliation: School of Medicine, "La Sapienza" University of Rome, Rome, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Berardi
authors.affiliation: Department of Emergency Medicine, University of Kansas, Kansas City, KS, United States.
authors.forename: Chad M
authors.initials: CM
authors.lastname: Cannon
authors.affiliation: Statistics, Veterans Affairs Medical Center, San Diego, CA, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Clopton
authors.affiliation: Department of Emergency Medicine, University of California, San Diego, La Jolla, CA, United States.
authors.forename: Sean-Xavier
authors.initials: SX
authors.lastname: Neath
authors.affiliation: Department of Pathology, University of Maryland, Baltimore, MD, United States.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Christenson
authors.affiliation: Department of Surgery, Virginia Commonwealth University, Richmond, VA, United States.
authors.forename: Christopher
authors.initials: C
authors.lastname: Hogan
authors.affiliation: Department of Emergency Medicine, University of California, San Diego, La Jolla, CA, United States.
authors.forename: Gary
authors.initials: G
authors.lastname: Vilke
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of California, San Diego, La Jolla, California, United States.
authors.forename: Alan
authors.initials: A
authors.lastname: Maisel
mesh_terms: D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D003362:Cost-Benefit Analysis; D042241:Early Diagnosis; D004562:Electrocardiography; D004636:Emergency Service, Hospital / Q000191:economics / Q000592:standards / Q000706:statistics & numerical data; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006020:Glycopeptides / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis*; D010343:Patient Admission / Q000191:economics / Q000592:standards / Q000706:statistics & numerical data; D010351:Patient Discharge / Q000706:statistics & numerical data; D010359:Patient Readmission / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment / Q000191:economics / Q000379:methods; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D006020:Glycopeptides; D019210:Troponin I; C048197:copeptins
keywords: Copeptin; Discharge; Hospitalization; Myocardial infarction; Stress testing