Effects of xamoterol a new beta-adrenoceptor partial agonist, in patients with angina pectoris.
The effects of xamoterol on exercise capacity have been evaluated in 10 patients with angina pectoris and well-preserved left ventricular function. Compared to placebo a single 200 mg dose of xamoterol produced a slight but insignificant increase in exercise capacity. At maximum work load, ST-T segment depression was reduced (3 mm and 2.19 mm after placebo and xamoterol, respectively; p less than 0.05). The changes paralleled an insignificant reduction in maximal heart rate and pressure-rate product. At rest, xamoterol increased the heart rate from 80 to 86 beats/min. Thus, at rest, when sympathetic tone is low, xamoterol acts as a beta-receptor agonist but during exercise, when sympathetic tone is high, xamoterol acts as an antagonist and reduces myocardial ischaemia.
Barrios
L
L
Geboers
J
J
Piessens
J H
JH
de Geest
H
H
D000318:Adrenergic beta-Agonists / Q000097:blood / Q000627:therapeutic use*; D000787:Angina Pectoris / Q000188:drug therapy*; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion; D011412:Propanolamines / Q000097:blood / Q000627:therapeutic use*; D011897:Random Allocation; D017307:Xamoterol
D000318:Adrenergic beta-Agonists; D011412:Propanolamines; D017307:Xamoterol