title: B-type natriuretic peptide and left ventricular dysfunction on exercise echocardiography in patients with chronic aortic regurgitation.
abstract: OBJECTIVE
  To determine whether plasma levels of B-type natriuretic peptide (BNP) predict left ventricular (LV) dysfunction on exercise echocardiography in patients with moderate to severe aortic regurgitation (AR).
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Outpatient cardiology departments.
  
  
  METHODS
  39 asymptomatic or mildly symptomatic patients with chronic moderate to severe AR and a normal LV ejection fraction (>50%), and 10 normal controls.
  
  
  METHODS
  Plasma level of BNP and echocardiographic measures of LV function at rest and immediately after treadmill exercise.
  
  
  RESULTS
  LV end systolic volume index (LVESVI) was significantly increased in AR patients with normal BNP (<or=12 pmol/l) compared with controls (mean (SD) 32 (13) vs 17 (7) ml/m(2), p = 0.002) but was similar for AR patients with normal and elevated BNP (38 (16), p = 0.14). In AR patients there was no association between plasma BNP and measures of LV function on echocardiography at rest (r<0.30, p>0.05 for all). However, there were modest but statistically significant associations between the plasma level of BNP and severity of AR indicated by a greater AR:LV outflow tract width ratio (r = 0.37, p = 0.02) and lower diastolic blood pressure (r = -0.44, p = 0.004). Increased BNP was also associated with a greater LVESVI (r = 0.33, p = 0.04) and lower LV longitudinal strain rate (r = -0.037, 0.02) on echocardiography after exercise.
  
  
  CONCLUSIONS
  In moderate to severe AR compensatory LV remodelling can occur with no increase in plasma BNP. Increased BNP is associated with more severe regurgitation and changes consistent with early LV dysfunction on exercise echocardiography.
authors.affiliation: Department of Cardiology, Middlemore Hospital, Auckland, New Zealand.
authors.forename: R S
authors.initials: RS
authors.lastname: Gabriel
authors.forename: A J
authors.initials: AJ
authors.lastname: Kerr
authors.forename: V
authors.initials: V
authors.lastname: Sharma
authors.forename: I S L
authors.initials: IS
authors.lastname: Zeng
authors.forename: R A H
authors.initials: RA
authors.lastname: Stewart
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002908:Chronic Disease; D025401:Echocardiography, Stress / Q000379:methods; D005080:Exercise Test / Q000379:methods; D006801:Humans; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain