Article

Plasma B-type natriuretic peptide (BNP) levels obtained at rest have
been previously shown to be correlated with the global functional capacity
measures of peak oxygen uptake (V(O(2peak))) and the minute ventilation/carbon
dioxide (VE/V(O(2))) slope. The purpose of this study was to assess the
relationship of the plasma BNP level to the rate-pressure product (RPP) as an
indicator of central or cardiac work capacity. METHODS: Twenty-two subjects (12
men), mean age 57 +/- 12 years, diagnosed with heart failure (8 ischemic/14
nonischemic) were recruited. All subjects were stable on optimal medical therapy
for at least 1 month. Blood samples for BNP level analysis were obtained at rest.
Subjects underwent a symptom-limited treadmill exercise test using a ramping
protocol while V(O(2)), heart rate (HR), and blood pressure (BP) were monitored.
Correlation analyses were conducted to assess the relationship of BNP level to
RPP level, V(O(2peak), VE/V(O(2)) slope, end-tidal CO(2) pressure (P(ET)CO(2)),
and left ventricular ejection fraction (LVEF). RESULTS: Resting BNP levels were
significantly correlated with RPP levels (r = -0.69). The BNP level and the RPP
level were correlated with V(O(2peak)) (r = -0.63 and r = 0.66, respectively) and
VE/V(O(2)) slope (r = 0.53 and r = -0.54, respectively). The RPP level but not
the BNP level was correlated with P(ET)CO(2) (r = 0.57). Neither BNP nor RPP
levels were well correlated with LVEF (r = -0.26 and r = 0.14, respectively).
DISCUSSION: The results of this study suggest that resting plasma BNP level may
be a useful clinical measure for evaluating both global functional capacity and
myocardial specific work capacity in individuals with heart failure.

Langue : ANGLAIS

Tiré à part : OUI