title: NT-pro-BNP during isotonic and isometric exercise in heart failure patients with preserved LV ejection fraction.
abstract: BACKGROUND
  NT-pro-BNP level is increased in both systolic and diastolic heart failure (HF) and furthermore increases more during exercise. In diastolic HF, NT-pro-BNP might increase more during isometric exercise than during isotonic exercises because of increased afterload. We studied NT-pro-BNP values during isometric (hand-grip) and isotonic (cycloergometer) exercise in HF patients with preserved left ventricular ejection fraction and different degrees of diastolic dysfunction.
  
  
  METHODS
  We studied 87 patients, aged 58 ± 7.9 years, 42.6% females, with heart failure with LVEF > 40% and diastolic dysfunction. The patients were randomly distributed in two groups: 43 patients (Group I) and 44 patients (Group II). Group I underwent ramp exercise testing on a cycloergometer. Group II performed an isometric handgrip test. Plasma NT-pro-BNP levels were measured at rest and immediately after exercise.
  
  
  RESULTS
  An abnormal relaxation (AR) pattern was recorded in 30 patients of Group I and 31 patients of Group II. Pseudonormalisation (PSN) and restrictive (R) pattern were noted in 13 patients of each group. As concerns Group I, NT-pro-BNP levels were increased in all patients, particularly in those with PSN or R pattern (p < 0.05). During exercise NT-pro-BNP decreases significantly in AR (1033 ± 516.63 to 800.51 ± 675.89 pg/mL) but not in PSN or R patients (1656.75 ± 977.48 to 1486.38 ± 1182.51 pg/mL). For Group II, NT-pro-BNP registered a similar increase as in Group I, with maximal values in PSN or R subgroup as compared to abnormal relaxation (p < 0.05). At peak exercise, NT-pro-BNP was practically unchanged as compared to the rest values for the whole group (-6%) and for the two subgroups (AR -6.7% and PSN or R -5.21%). We compared rest and exercise NT-pro-BNP with E/E' ratio > 12 in order to identify increased diastolic filling pressure in the LV; AUC was 0.70 and 0.66 for rest and exercise NT-pro-BNP in case of isotonic testing and 0.74 and 0.72 in case of isometric exercise.
  
  
  CONCLUSIONS
  Our data suggest that in HF patients with preserved left ventricular ejection fraction, moderate isotonic and isometric exercises do not determine a significant increase (isometric exercise) or even decrease (isotonic exercise) in the value of NT-pro-BNP.
authors: Dumitru Tudor
authors: DT
authors: Zdrenghea
authors: Maria
authors: M
authors: Ilea
authors: Gyorgy
authors: G
authors: Bodizs
authors: Adela
authors: A
authors: Sitar-Tăut
authors: Mihnea
authors: M
authors: Zdrenghea
authors: Dana
authors: D
authors: Pop
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001642:Bicycling; D015415:Biomarkers / Q000097:blood; D005080:Exercise Test / Q000379:methods*; D005260:Female; D018737:Hand Strength; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007537:Isometric Contraction; D007551:Isotonic Contraction; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D012383:Romania; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D016277:Ventricular Function, Left
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain