title: Impact of beta-blocker treatment on the prognostic value of currently used risk predictors in congestive heart failure.
abstract: OBJECTIVE
  This prospective study tested the impact of beta-blocker treatment on currently used risk predictors in congestive heart failure (CHF).
  
  
  BACKGROUND
  Given the survival benefit obtained by beta-blockade, risk stratification by factors established in the "pre-beta-blocker era" may be questioned.
  
  
  METHODS
  The study included 408 patients who had CHF with left ventricular ejection fraction (LVEF) <45%, all treated with an angiotensin-converting enzyme inhibitor or angiotensin type 1 receptor antagonist, who were classified into those receiving a beta-blocker (n = 165) and those who were not (n = 243). In all patients, LVEF, peak oxygen consumption (peakVO(2)), plasma norepinephrine (NE) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were determined.
  
  
  RESULTS
  Although the New York Heart Association functional class (2.2 +/- 0.7 vs. 2.3 +/- 0.7), peakVO(2) (14.4 +/- 5.2 ml/min per kg vs. 14.4 +/- 5.5 ml/min per kg) and NT-proBNP (337 +/- 360 pmol/l vs. 434 +/- 538 pmol/l) were similar in the groups with and without beta-blocker treatment, the group with beta-blocker treatment had a lower heart rate (68 +/- 30 beats/min vs. 76 +/- 30 beats/min), lower NE (1.7 +/- 1.2 nmol/l vs. 2.5 +/- 2.2 nmol/l) and higher LVEF (24 +/- 10% vs. 21 +/- 9%; all p < 0.05). Within one year, 34% of patients without beta-blocker treatment, but only 16% of those with beta-blocker treatment (p < 0.001), reached the combined end point, defined as hospital admission due to worsening CHF and/or cardiac death. A beneficial effect of beta-blocker treatment was most obvious in the advanced stages of CHF, because the end-point rates were markedly lower (all p < 0.05) in the group with beta-blocker treatment versus the group without it, as characterized by peakVO(2) <10 ml/min per kg (26% vs. 64%), LVEF < or = 20% (25% vs. 45%), NE >2.24 nmol/l (18% vs. 40%) and NT-proBNP >364 pmol/l (27% vs. 45%), although patients with beta-blocker treatment received only 37 +/- 21% of the maximal recommended beta-blocker dosages.
  
  
  CONCLUSIONS
  The prognostic value of variables used for risk stratification of patients with CHF is markedly influenced by beta-blocker treatment. Therefore, in the beta-blocker era, a re-evaluation of the selection criteria for heart transplantation is warranted.
authors.affiliation: Department of Cardiology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Zugck
authors.forename: Armin
authors.initials: A
authors.lastname: Haunstetter
authors.forename: Carsten
authors.initials: C
authors.lastname: Krüger
authors.forename: Robert
authors.initials: R
authors.lastname: Kell
authors.forename: Dieter
authors.initials: D
authors.lastname: Schellberg
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kübler
authors.forename: Markus
authors.initials: M
authors.lastname: Haass
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain; D009419:Nerve Tissue Proteins / Q000097:blood; D009638:Norepinephrine / Q000097:blood; D010101:Oxygen Consumption / Q000187:drug effects; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D011446:Prospective Studies; D016019:Survival Analysis; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality; D016277:Ventricular Function, Left / Q000187:drug effects
chemical_list: D000319:Adrenergic beta-Antagonists; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D009638:Norepinephrine