Beta-sympathetic blockade with chronotropic compensation in the management of heart disease.

Abstract

This presentation briefly describes the sympathetic and parasympathetic control of the heart, particularly in relation to coronary vascular effects. Autonomic disturbances following myocardial infarction and their significance are discussed. The influence of the autonomic system in chronic coronary heart disease is considered, particularly in relation to the beneficial effects which may be obtained by the combined use of beta-blocking drugs and cardiac pacing. Nine anginal patients with spontaneous or drug-induced bradycardia received temporary pacing and 27 others had pacemakers implanted. Pain was well controlled in the former group. Long term pacing produced worth-while benefit in 67% of the patients followed for periods up to 6 months, the figure falling to 50% among those followed for 24 months. Eight of the 27 relapsed. Thus, correction of bradycardia by pacing often produced a beneficial long term effect. A second group of 14 patients with ventricular arrhythmias was treated with beta-blocking agents combined with pacing. So far, 10 of these 14 have had their arrhythmias controlled either by the initial or by a modified drug regime. The results indicate that among patients with chronic coronary artery disease, beta-blockade to minimize cardiac sympathetic activity, coupled with pacing to prevent loss of chronotrophic control, often represents an effective combination for the management of refractory angina or arrhythmias.