title: [Usefulness of B-type natriuretic peptide in emergency medicine].
abstract: OBJECTIVE
  Acute dyspnea is frequent in emergency medicine. The B-type natriuretic peptide is a polypeptide, released by ventricular myocytes directly proportional to wall tension, for lowering renin-angiotensin-aldosterone activation. Conversely, NT-proBNP has no physiological activity. BNP and NT-proBNP concentration closely correlate to various indicators of heart failure.
  
  
  BACKGROUND
  Numerous studies have demonstrated high usefulness of BNP and NT-proBNP to diagnose heart failure, which is the main cause of acute dyspnea in emergency medicine. The diagnostic accuracy of BNP and NT-proBNP seems similar, and is higher than that of the emergency physician. Bedside dosages are now available, with high sensibility and specificity for the diagnosis of heart failure. For BNP, threshold value is ranging from 100 to 300 pg/ml in patients aged over 65 years; for NT-proBNP the threshold value is 1000 to 2000 pg/ml in elderly patients. Briefly, heart failure is unlikely when BNP is below 100 pg/ml (NT-proBNP<500 pg/ml), and very likely when BNP is higher than 400 pg/ml (or NT-proBNP>2000 pg/ml).
  
  
  CONCLUSIONS
  Early rapid measurement of BNP could improved the evaluation and treatment of patients with acute dyspnea and reduce the total cost of treatment.
authors.affiliation: Service d'accueil des urgences, APHP, groupe hospitalier Pitié-Salpêtrière, 47-83, boulevard de l'Hôpital, 75013 Paris, France. patrick.ray@psl.ap-hop-paris.fr
authors.forename: P
authors.initials: P
authors.lastname: Ray
authors.forename: Y
authors.initials: Y
authors.lastname: Lefort
mesh_terms: D000208:Acute Disease; D015415:Biomarkers / Q000097:blood; D004417:Dyspnea / Q000209:etiology; D004635:Emergency Medicine; D006333:Heart Failure / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain