title: Influence of history of heart failure on diagnostic performance and utility of B-type natriuretic peptide testing for acute dyspnea in the emergency department.
abstract: BACKGROUND
  The aim of this study was to assess the impact of a history of heart failure (HF) on emergency department (ED) B-type natriuretic peptide (BNP) testing and impact of feedback of BNP level to ED physicians.
  
  
  METHODS
  Admission BNP was measured in 143 patients (mean age 79 +/- 10 years) presenting to the ED with dyspnea. Emergency department physicians scored probability of HF as cause of dyspnea and categorized cause of dyspnea. An independent cardiologist determined cause of dyspnea after chart review. In 83 patients, ED physicians rescored and reclassified patients after BNP measurement and evaluated test utility.
  
  
  RESULTS
  The area under the receiver operating characteristic curve for BNP diagnosis of HF cause of dyspnea was significantly worse in patients with history of HF than those without (0.74 vs 0.94, P < .01) and in those with left ventricular ejection fraction <50% (0.64 vs 0.87, P < .05). A BNP cut point of 100 pg/mL had 100% sensitivity but only 41% specificity for diagnosing acute HF, whereas a cut point of 400 pg/mL had 87% sensitivity and 76% specificity. Emergency department physicians rated BNP useful in 64% of patients, and diagnostic uncertainty was reduced from 53% to 25% (P < .001).
  
  
  CONCLUSIONS
  B-type natriuretic peptide test performance for diagnosis of dyspnea cause is significantly reduced in patients with a history of HF and must be taken into consideration in the evaluation of such patients in the ED.
authors.affiliation: Department of Cardiology, Concord Hospital, University of Sydney, Sydney, Australia.
authors.forename: Tommy
authors.initials: T
authors.lastname: Chung
authors.forename: Andrew
authors.initials: A
authors.lastname: Sindone
authors.forename: Fiona
authors.initials: F
authors.lastname: Foo
authors.forename: Andrew
authors.initials: A
authors.lastname: Dwyer
authors.forename: Richard
authors.initials: R
authors.lastname: Paoloni
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Janu
authors.forename: Helen
authors.initials: H
authors.lastname: Wong
authors.forename: Judith
authors.initials: J
authors.lastname: Hall
authors.forename: Saul B
authors.initials: SB
authors.lastname: Freedman
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D004417:Dyspnea / Q000097:blood* / Q000209:etiology*; D004636:Emergency Service, Hospital; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000175:diagnosis*; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*
chemical_list: D020097:Natriuretic Peptide, Brain