Haemodynamic dose-response effects of i.v. penbutolol in angina pectoris.

Abstract

The haemodynamic dose-response effects of intravenous penbutolol, a newer beta-adrenoceptor antagonist with intrinsic sympathomimetic activity but without cardioselectivity, were evaluated in 10 patients with angiographically documented coronary artery disease. Following four logarithmetically cumulative i.v. boluses (0.5-4 mg dosage range) there was a log linear increase in plasma penbutolol concentration; the levels achieved (51 +/- 8 to 219 +/- 19 ng/ml) were in the therapeutic range (12 to 250 ng/ml). Penbutolol resulted in a linear decrease in heart rate (maximum delta HR - 4 beats/min; P less than 0.01); there was a small increase in pulmonary artery occluded pressure which reached its maximum at the lower doses (maximum delta PAOP + 1 mm Hg; P less than 0.01). The resting cardiac output, blood pressure and calculated systemic vascular resistance were unchanged. During 4 min steady-state supine bicycle exercise there was attenuation of exercise cardiac output (delta C.I. - 0.6 1 min-1 m-2; P less than 0.01) and systolic pressor response (delta SBP - 13 mm Hg; P less than 0.01) compared with control observations without change in other measured or derived variables. The haemodynamic profile of penbutolol compared favourably with other beta-adrenoceptor antagonists previously evaluated under similar conditions in patients with ischaemic heart disease. Over the i.v. dose-range evaluated penbutolol attenuated exercise-induced angina with a relatively modest depression of cardiac performance; the small change induced in resting haemodynamic variables may, in part, have been contributed to by the intrinsic sympathomimetic activity of penbutolol.

• Authors: B Silke, S P Verma, M Hussain, G I Nelson, R C Okoli, S H Taylor
• Journal: British journal of clinical pharmacology (Br J Clin Pharmacol) Vol. 16 Issue 5 Pg. 529-35 (Nov 1983) ISSN: 0306-5251 [Print] England
• PMID: 6315039 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Propanolamines
• Receptors, Adrenergic, beta
• Penbutolol

Topics

• Adult
• Angina Pectoris (physiopathology)
• Dose-Response Relationship, Drug
• Hemodynamics (drug effects)
• Humans
• Male
• Middle Aged
• Penbutolol (blood, pharmacology)
• Physical Exertion
• Propanolamines (pharmacology)
• Receptors, Adrenergic, beta (drug effects)