title: The roles of natriuretic peptides in pericardial fluid in patients with heart failure.
abstract: BACKGROUND
  It is well known that the plasma concentrations of atrial and brain natriuretic peptides, as cardiac hormones, are elevated in heart failure.
  
  
  OBJECTIVE
  Pericardial fluid in patients with various heart diseases contains both natriuretic peptides that are released into the pericardial fluid. However, it is unknown whether these peptides reflect cardiac function in patients with various heart diseases, more than both the peptides in blood.
  
  
  METHODS
  Plasma and pericardial fluid samples were obtained from 22 patients undergoing cardiac surgery for the measurement of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels in plasma and pericardial fluid.
  
  
  RESULTS
  The ANP levels in pericardial fluid were higher in patients with impaired left ventricular systolic function (ejection fraction<50% versus>or=50%; 77.0+/-4.9 versus 14.0+/-50.9, p=0.017), but not BNP.However, BNP levels in pericardial fluid were significantly higher in patients with left ventricle dilatation (left ventricular diastolic dimension<or=54 mm versus>54 mm; 130.3+/-68.9: 709.7+/-324.7, p=0.0168). Moreover, BNP levels in pericardial fluid were significantly higher in Grade III than Grade II and I (Grade I: echo-free space<5 mm, Grade II: 5-10 mm, Grade III: >10 mm).
  
  
  CONCLUSIONS
  These results suggest that BNP levels in pericardial fluid served as more sensitive and accurate indicators of left ventricular diastolic dysfunction, and that increased BNP levels in pericardial fluid may have an important pathophysiologic role in heart failure as a cardiocyte-derived antifibrotic factor.
authors.affiliation: Department of Cardiovascular Surgery, Tokyo Metropolitan Hiroo General Hospital, Tokyo, Japan. masa-cvs@hiroo-hospital.metro.tokyo.jp
authors.forename: Masazumi
authors.initials: M
authors.lastname: Watanabe
authors.forename: Satoru
authors.initials: S
authors.lastname: Kawaguchi
authors.forename: Hideki
authors.initials: H
authors.lastname: Nakahara
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Hachimaru
mesh_terms: D009320:Atrial Natriuretic Factor / Q000032:analysis* / Q000097:blood; D015415:Biomarkers / Q000032:analysis* / Q000097:blood; D006348:Cardiac Surgical Procedures; D006333:Heart Failure / Q000097:blood / Q000503:physiopathology*; D006801:Humans; D016018:Least-Squares Analysis; D020097:Natriuretic Peptide, Brain / Q000032:analysis* / Q000097:blood; D010490:Pericardial Effusion / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor