title: [Utility of B-type natriuretic peptide measurement in outpatients with heart failure with preserved ejection fraction].
abstract: BACKGROUND
  Heart failure with preserved ejection fraction (HFPEF) is a highly prevalent syndrome that is difficult to diagnose in outpatients. The measurement of B-type natriuretic peptide (BNP) may be useful in the diagnosis of HFPEF, but with a different cutoff from that used in the emergency room. The aim of this study was to identify the BNP cutoff for a diagnosis of HFPEF in outpatients.
  
  
  RESULTS
  This prospective, observational study enrolled 161 outpatients (aged 68.1±11.5 years, 72% female) with suspected HFPEF. Patients underwent ECG, tissue Doppler imaging, and plasma BNP measurement, and were classified in accordance with algorithms for the diagnosis of HFPEF. HFPEF was confirmed in 49 patients, who presented higher BNP values (mean 144.4pg/ml, median 113pg/ml, vs. mean 27.6pg/ml, median 16.7pg/ml, p<0.0001). The results showed a significant correlation between BNP levels and left atrial volume index (r=0.554, p<0.0001), age (r=0.452; p<0.0001) and E/E' ratio (r=0.345, p<0.0001). The area under the ROC curve for BNP to detect HFPEF was 0.92 (95% confidence interval: 0.87-0.96; p<0.001), and 51pg/ml was identified as the best cutoff to detect HFPEF, with sensitivity of 86%, specificity of 86% and accuracy of 86%.
  
  
  CONCLUSIONS
  BNP levels in outpatients with HFPEF are significantly higher than in those without. A cutoff value of 51pg/ml had the best diagnostic accuracy in outpatients.
authors.affiliation: Departamento de Medicina Clínica, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brasil. Electronic address: lagoeiro@globo.com.
authors.forename: Antonio José Lagoeiro
authors.initials: AJ
authors.lastname: Jorge
authors.forename: Monica Di Calafiori
authors.initials: MD
authors.lastname: Freire
authors.forename: Mário Luiz
authors.initials: ML
authors.lastname: Ribeiro
authors.forename: Luiz Cláudio Maluhy
authors.initials: LC
authors.lastname: Fernandes
authors.forename: Pedro Gemal
authors.initials: PG
authors.lastname: Lanzieri
authors.forename: Bruno Afonso Lagoeiro
authors.initials: BA
authors.lastname: Jorge
authors.forename: João Gabriel B
authors.initials: JG
authors.lastname: Lage
authors.forename: Maria Luiza Garcia
authors.initials: ML
authors.lastname: Rosa
authors.forename: Evandro Tinoco
authors.initials: ET
authors.lastname: Mesquita
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis*; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010045:Outpatients; D011446:Prospective Studies; D015203:Reproducibility of Results; D013318:Stroke Volume
chemical_list: D020097:Natriuretic Peptide, Brain
keywords: B-type natriuretic peptide; Diastole; Diástole; Doentes ambulatórios; Heart failure; Insuficiência cardíaca; Outpatients; Peptídeo natriurético tipo B