Calcium antagonists and beta blockade--a useful combination
Geddes, J.S.
Postgraduate Medical Journal 59(Suppl 2): 62-69
1983
ISSN/ISBN: 0032-5473 PMID: 6136960 Document Number: 202283
Treatment of angina with a single drug often proves unsatisfactory because of dose-related unwanted effects or occasionally an adverse effect on the angina. A combination of a beta-blocking agent and a calcium antagonist drug might achieve satisfactory control of angina at acceptable doses of each drug. Widespread application of combination therapy would, however, be inappropriate if the beta-blocker component were to have adverse effects among patients with rest pain as a prominent symptom, suggestive of coronary 'spasm'. The reported adverse effects of beta-blocking agents are likely to be related to bradycardia and are not apparent if excessive slowing is avoided by individual dose adjustment or if bradycardia is corrected by pacing. Supposed failure of these agents to control cardiac pain not infrequently results from inadequate dosage. Combination therapy will attenuate the increases in heart rate and contractility resulting from stress while coronary perfusion will be maintained and the associated level of arterial blood pressure reduced. The theoretical benefits have been confirmed in clinical investigations in which the effect of combination therapy has been compared with that of one or both of the constituent drugs given alone. Reports of bradycardia (specific to inclusion of verapamil in the combination), hypotension or cardiac failure developing during combination therapy emphasize the need for careful dose titration of both beta-blocker and calcium antagonist in each patient. The possible additional role of nitrates is undefined, but inclusion of these agents is likely to prove especially valuable where left ventricular function is grossly impaired and in the management of unstable angina.