title: B-type natriuretic peptide levels are not a surrogate marker for invasive hemodynamics during management of patients with severe heart failure.
abstract: BACKGROUND
  We sought to assess the utility of serial BNP measurements in patients with severe heart failure and attempted to correlate values with invasively derived data.
  
  
  METHODS
  In a retrospective study, we analyzed serial BNP levels in patients receiving hemodynamically guided therapy for severe heart failure and sought correlation with invasively derived data.
  
  
  RESULTS
  Thirty-nine patients with New York Heart Association Class III-IV, with an ejection fraction of 35% or less, who had a pulmonary artery catheter inserted for hemodynamically tailored heart failure therapy, were identified and serial BNP measurements reviewed. BNP was estimated on admission, at 12 and 36 hours. Normally distributed variables are expressed as mean +/- SD and otherwise as median +/- interquartile range. Mean ejection fraction was 16% +/- 6%. Mean pulmonary artery occlusion pressures (PAOP) fell with therapy and were 25 +/- 7 mmHg, 18 +/- 7 mmHg and 19 +/- 7 mmHg at admission, 12 hours and 36 hours respectively ( P < 0.05). Median BNP levels fell from 1200 +/- 641 to 771 +/- 803 at 12 hours and to 805 +/- 771 at 36 hours (P < .001). There was no correlation between BNP and any hemodynamically derived variable. A change in BNP was not associated with a change in PAOP in any individual patient. Only 42% remained alive on medical therapy at 30 days.
  
  
  CONCLUSIONS
  In patients with severe heart failure, BNP levels do not accurately predict serial hemodynamic changes and do not obviate the need for pulmonary artery catheterization.
authors.affiliation: Kaufman Center for Heart Failure, Department of Cardiovascular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA. oneillj@ccf.org
authors.forename: J O
authors.initials: JO
authors.lastname: O'Neill
authors.forename: C E
authors.initials: CE
authors.lastname: Bott-Silverman
authors.forename: A T
authors.initials: AT
authors.lastname: McRae
authors.forename: R W
authors.initials: RW
authors.lastname: Troughton
authors.forename: K
authors.initials: K
authors.lastname: Ng
authors.forename: R C
authors.initials: RC
authors.lastname: Starling
authors.forename: J B
authors.initials: JB
authors.lastname: Young
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002407:Catheterization, Swan-Ganz; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain