title: Bioelectrical impedance analysis for heart failure diagnosis in the ED.
abstract: BACKGROUND
  The aim of this study was to evaluate bioimpedance vector analysis (BIVA) for the diagnosis of acute heart failure (AHF) in patients presenting with acute dyspnea to the emergency department (ED).
  
  
  METHODS
  Patients with acute dyspnea presenting to the ED were prospectively enrolled. Four parameters were assessed: resistance (R), reactance (Ra), total body water (TBW), and extracellular body water (EBW). Brain natriuretic peptide (BNP) measures and cardiac ultrasound studies were performed in all patients at admission. Patients were classified into AHF and non-AHF groups retrospectively by expert cardiologists.
  
  
  RESULTS
  Seventy-seven patients (39 men; age, 68±14years; weight, 79.8±20.6 kg) were included. Of the 4 BIVA parameters, Ra was significantly lower in the AHF compared to non-AHF group (32.7±14.3 vs 45.4±19.7; P<.001). Brain natriuretic peptide levels were significantly higher in the AHF group (1050.3±989 vs 148.7±181.1ng/L; P<.001). Reactance levels were significantly correlated to BNP levels (r=-0.5; P<.001). Patients with different mitral valve Doppler profiles (E/e'≤8, E/e' ≥9 and <15, and E/e'≥15) had significant differences in Ra values (47.9±19.9, 34.7±19.4, and 31.2±11.7, respectively; P=.003). Overall, the sensitivity of BIVA for AHF diagnosis with a Ra cutoff at 39Ω was 67% with a specificity of 76% and an area under the curve at 0.76. However, Ra did not significantly improve the area under the curve of BNP for the diagnosis of AHF (P=not significant).
  
  
  CONCLUSIONS
  In a population of patients presenting to the ED with dyspnea, BIVA was significantly related to the AHF status but did not improve the diagnostic performance for AHF in addition to BNP alone.
authors.affiliation: University Hospital of LYON, Medical Intensive Care Unit, Hospital Edouard Herriot, Hospices Civils de Lyon, France. Electronic address: nathalie.genot@voila.fr.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Génot
authors.affiliation: University Hospital of Lyon, Centre d'Investigation Clinique de Lyon (CIC), Hospital L. Pradel, Lyon, France; University Hospital of LYON, Coronary Care Unit, Hospital L. Pradel, Lyon, France.
authors.forename: Nathan
authors.initials: N
authors.lastname: Mewton
authors.affiliation: University Hospital of LYON, Coronary Care Unit, Hospital L. Pradel, Lyon, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Bresson
authors.affiliation: University Hospital of LYON, Coronary Care Unit, Hospital L. Pradel, Lyon, France.
authors.forename: Oualid
authors.initials: O
authors.lastname: Zouaghi
authors.affiliation: University Hospital of LYON, Emergency Department of Cardiology, Hospital L.Pradel, Lyon, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Francois
authors.affiliation: University Hospital of LYON, Medical Intensive Care Unit, Hospital Edouard Herriot, Hospices Civils de Lyon, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Delwarde
authors.affiliation: University Hospital of LYON, Coronary Care Unit, Hospital L. Pradel, Lyon, France; University Hospital of LYON, Emergency Department of Cardiology, Hospital L.Pradel, Lyon, France.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Kirkorian
authors.affiliation: University Hospital of LYON, Coronary Care Unit, Hospital L. Pradel, Lyon, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Bonnefoy-Cudraz
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D001834:Body Water; D015331:Cohort Studies; D004417:Dyspnea / Q000175:diagnosis* / Q000209:etiology; D004452:Echocardiography; D017097:Electric Impedance; D004636:Emergency Service, Hospital; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011446:Prospective Studies
chemical_list: D020097:Natriuretic Peptide, Brain