title: Neuro-hormonal activation predicts ventilatory response to exercise and functional capacity in patients with heart failure.
abstract: BACKGROUND
  Heart failure (HF) is characterised by reduced tolerance to effort, associated with progressive fatigue and dyspnoea. Neuro-hormonal activation is a hallmark of HF and influences its clinical evolution.
  
  
  OBJECTIVE
  To evaluate the relationship between neuro-hormonal activation, exercise capacity and ventilatory efficiency.
  
  
  RESULTS
  154 HF patients (127 males, 62 +/- 1 years) underwent cardiopulmonary exercise testing and resting blood sampling for assay of plasma brain natriuretic peptide (BNP), NT-proBNP, norepinephrine, epinephrine, aldosterone and plasma renin activity (PRA). BNP and NT-proBNP levels correlated with peak oxygen consumption (VO2) (both R = -0.53, p < 0.001), VE/VCO2 slope (R = 0.56; p < 0.001 and R = 0.58; p < 0.001, respectively) and maximum workload (R = -0.49; p < 0.001 and R = -0.47; p < 0.001, respectively). Norepinephrine correlated slightly less with peak VO2 (R = -0.38, p < 0.001), VE/VCO2 (R = 0.45; p < 0.001) and maximum workload (R = -0.35; p < 0.001). There was a significant inverse correlation between left ventricular ejection fraction and BNP (R = -0.48, p < 0.001), NT-proBNP (R = -0.42; p < 0.001) and norepinephrine (R = -0.43; p < 0.001). Weaker correlations were found for PRA, exercise parameters and ejection fraction. ROC curves showed that BNP was able to identify patients with peak VO2 < 14 ml/min/kg (cut-off 98 pg/ml, AUC 0.775) and a VE/VCO2 > 35 (cut-off 183 pg/ml, AUC 0.797), as well as NT-proBNP (cut-off 537 pg/ml, AUC 0.799 and cut-off 1010 pg/ml, AUC 0.768, respectively) and norepinephrine (cut-off 454 pg/ml, AUC 0.716 and cut-off 575 pg/ml, AUC 0.783, respectively).
  
  
  CONCLUSIONS
  Haemodynamic impairment (as indicated by BNP and NT-proBNP plasma values) and sympathetic activation predict exercise capacity and ventilatory efficiency in HF patients.
authors.affiliation: CNR Institute of Clinical Physiology, National Research Council, Via Moruzzi 1, 56124 Pisa, Italy. passino@ifc.cnr.it
authors.forename: Claudio
authors.initials: C
authors.lastname: Passino
authors.forename: Roberta
authors.initials: R
authors.lastname: Poletti
authors.forename: Francesca
authors.initials: F
authors.lastname: Bramanti
authors.forename: Concetta
authors.initials: C
authors.lastname: Prontera
authors.forename: Aldo
authors.initials: A
authors.lastname: Clerico
authors.forename: Michele
authors.initials: M
authors.lastname: Emdin
mesh_terms: D000450:Aldosterone / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D018450:Disease Progression; D004837:Epinephrine / Q000097:blood*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D009638:Norepinephrine / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D010446:Peptide Fragments / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood; D012123:Pulmonary Ventilation / Q000502:physiology*; D012083:Renin / Q000097:blood*; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D011498:Protein Precursors; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D000450:Aldosterone; D012083:Renin; D009638:Norepinephrine; D004837:Epinephrine