Pirbuterol, an oral beta-adrenergic receptor agonist, in the treatment of chronic cardiac failure.

Publisher Website
Google Scholar
Abstract
Pirbuterol (PB), an oral .beta.-adrenergic-receptor agonist, has the pharmacologic effects of vasodilation and positive inotropy. The value of PB in the long-term therapy of chronic cardiac failure was determined. A double-blind, randomized, 7-wk trial comparing PB (20 mg, 3 times daily) with placebo in 12 patients was followed by 12 wk of open PB therapy. Dose-dependent nervousness and tremulousness limited the unit PB dose to < 20 mg in 6 patients. In all patients, clinical status, exercise tolerance and maximal O2 uptake, left ventricular echocardiographic dimension and cardiothoracic ratio were unchanged from control after 7 wk of placebo or PB or after 12-19 wk of PB. To assess the adequacy of 20 mg of PB, the dose-response relations of cardiocirculatory effects to 10, 15, 20 and 30 mg of PB were compared in 7 of the above patients and 9 other patients. Cardiac output was significantly elevated and wedge pressure reduced after all 4 doses, but these changes were sustained for 6 h after 20- and 30-mg doses only. The role of PB in the management of chronic cardiac failure appears to be limited; judgment of its utility must await the results of additional controlled trials.