title: Natriuretic peptide response to dynamic exercise in patients with atrial fibrillation.
abstract: BACKGROUND
  In patients with atrial fibrillation (AF) information regarding exercise release of atrial natriuretic peptide (ANP) is sparse and data on plasma brain natriuretic peptide (BNP) response to exercise is lacking. The aim of this study was to investigate plasma ANP and BNP response to exercise in patients with permanent AF and to assess if the response was different from the response in healthy age- and sex-matched control subjects.
  
  
  METHODS
  Plasma venous concentrations of ANP and BNP were determined at rest, at peak exercise and 30 min from the end of exercise in 38 patients with permanent AF and in 43 age- and sex-matched healthy control subjects.
  
  
  RESULTS
  Plasma concentrations of ANP and BNP were significantly higher in AF patients compared with the healthy control group at rest, peak exercise and after 30 min of recovery (p<0.0001). ANP and BNP increased significantly during exercise in both patients with AF and in the healthy control subjects (p<0.05). The increase in plasma concentration of ANP and BNP during exercise was significantly higher in AF patients compared with healthy controls (p=0.0002 for ANP; p<0.0001 for BNP). In the recovery period plasma BNP decreased significantly (p<0.0001) where as the decrease in plasma ANP was insignificant (p=0.4).
  
  
  CONCLUSIONS
  Patients with permanent AF have elevated levels of ANP and BNP at rest and exhibit much higher exercise release compared to healthy control subjects. This enhanced secretion of potent vasodilating and natriuretic agents may represent an important compensatory mechanism to improve exercise capacity in patients with AF.
authors.affiliation: Department of Cardiology, Herlev University Hospital, Herlev, Denmark. engelmann@dadlnet.dk
authors.forename: Mads D M
authors.initials: MD
authors.lastname: Engelmann
authors.forename: Lea
authors.initials: L
authors.lastname: Niemann
authors.forename: Inge-Lis
authors.initials: IL
authors.lastname: Kanstrup
authors.forename: Knud
authors.initials: K
authors.lastname: Skagen
authors.forename: John
authors.initials: J
authors.lastname: Godtfredsen
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000097:blood / Q000503:physiopathology*; D009320:Atrial Natriuretic Factor / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D011237:Predictive Value of Tests; D013318:Stroke Volume / Q000502:physiology
chemical_list: D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor