brain natriuretic peptide levels predict functional capacity in patients with chronic heart failure.
OBJECTIVE
The goal of this study was to determine if brain natriuretic peptide (BNP) levels are associated with exercise capacity in patients with chronic heart failure (HF).


BACKGROUND
Plasma levels of BNP are increased subject to the degree of systolic and diastolic left ventricular dysfunction in patients with chronic HF. Exercise testing is useful to assess functional capacity and prognosis in chronic HF.


METHODS
We prospectively studied 70 consecutive patients with chronic HF (60.3 +/- 10.4 years, 51 men) referred for cardiopulmonary exercise testing. Resting BNP was obtained after 10 min of supine rest before symptom-limited bicycle exercise testing.


RESULTS
In patients with chronic HF, BNP levels correlated with oxygen uptake (VO(2)), both at anaerobic threshold (VO(2)AT: r = -0.54, p < 0.001) and peak exercise (peak VO(2): r = -0.56, p < 0.001). Impairment of ventilatory efficiency (EqCO(2): r = 0.43, p < 0.001) and maximum exercise level (W % predicted: r = -0.44, p < 0.05) correlated less well with BNP. There was a significant inverse correlation between left ventricular ejection fraction and BNP (r = -0.50, p < 0.05). Brain natriuretic peptide discriminated well chronic HF patients with a peak VO(2) <10 ml/min/kg (area under the receiver operating characteristic [ROC] 0.93) or <14 ml/min/kg (area under the ROC 0.72). A BNP >316 pg/ml was associated with a risk ratio of 6.8 (95% confidence interval, 2.3 to 19.8) for a reduced exercise capacity with a peak VO(2) <14 ml/min/kg.


CONCLUSIONS
Brain natriuretic peptide is clearly associated with exercise capacity in chronic HF. Brain natriuretic peptide levels show a significant correlation with the impairment of VO(2) at peak exercise and anaerobic threshold. Brain natriuretic peptide is able to differentiate between chronic HF patients with moderately and severely impaired exercise capacity.
Medical Clinic I, University Hospital, University of Technology, Aachen, Germany. SKrueger@ukaachen.de
Stefan
S
Krüger
Jürgen
J
Graf
Dagmar
D
Kunz
Tina
T
Stickel
Peter
P
Hanrath
Uwe
U
Janssens
D002908:Chronic Disease; D005080:Exercise Test; D017079:Exercise Tolerance; D006333:Heart Failure / Q000097:blood* / Q000503:physiopathology; D006801:Humans; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012372:ROC Curve
D020097:Natriuretic Peptide, Brain