Dobutamine potentiates the peripheral chemoreflex in patients with congestive heart failure.
BACKGROUND
beta-Adrenergic agonists may increase chemoreflex sensitivity to hypoxia in normal humans. Chemoreflex function is important in the pathophysiology of heart failure. Whether the beta-1 agonist dobutamine, which is frequently administered to patients with heart failure, alters their chemoreflex sensitivity is not known.


METHODS
We tested the hypothesis that dobutamine increases chemoreflex sensitivity in patients with congestive heart failure (CHF) using a randomized, double-blinded, placebo-controlled study design. We assessed the influence of dobutamine on minute ventilation and hemodynamics during normoxic breathing and during peripheral chemoreflex deactivation by hyperoxia (100% O(2)) in 9 patients with CHF.


RESULTS
Dobutamine increased minute ventilation in patients with CHF (9.4+/-0.9 versus 8.4+/-0.7 L/min, P=.005) during normoxia. Peripheral chemoreflex deactivation by hyperoxia suppressed the ventilatory effects of dobutamine (10.4+/-1.4 L/min for dobutamine versus 10.0+/-1.2 L/min for placebo, P=.34).


CONCLUSIONS
Dobutamine increases ventilation during normoxia, but not during hyperoxia in patients with CHF. We conclude that dobutamine enhances peripheral chemoreflex sensitivity in patients with congestive heart failure.
Department of Cardiology, Erasme Hospital, 808 Lennik Road, 1070 Brussels, Belgium.
Sonia
S
Velez-Roa
Philippe
P
van de Borne
Virend K
VK
Somers
D000328:Adult; D000368:Aged; D002628:Chemoreceptor Cells / Q000187:drug effects*; D004280:Dobutamine / Q000009:adverse effects*; D004311:Double-Blind Method; D005260:Female; D006333:Heart Failure / Q000188:drug therapy*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D000860:Hypoxia / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000187:drug effects*
D004280:Dobutamine