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Beta-sympathetic blockade with chronotropic compensation in the management of heart disease
Insights
Cardiac pacing and beta-blockers effectively manage chronic coronary artery disease by controlling heart rate and sympathetic activity. This combination offers significant benefits for patients with angina and arrhythmias.
Area of Science:
- Cardiology
- Autonomic Nervous System Physiology
- Pharmacology
Background:
- The autonomic nervous system, comprising sympathetic and parasympathetic branches, significantly influences cardiac function and coronary vascular effects.
- Autonomic disturbances post-myocardial infarction and their implications in chronic coronary heart disease (CHD) are critical considerations.
- The interplay between autonomic activity and cardiac health necessitates exploring therapeutic interventions.
Purpose of the Study:
- To investigate the role of autonomic disturbances in coronary heart disease.
- To evaluate the efficacy of combined beta-blocking drugs and cardiac pacing in managing chronic coronary artery disease.
- To assess the impact of correcting bradycardia and controlling arrhythmias through pacing and beta-blockade.
Main Methods:
- Review of sympathetic and parasympathetic control of the heart and coronary vasculature.
- Analysis of autonomic disturbances following myocardial infarction.
- Clinical evaluation of temporary and permanent cardiac pacing in 36 patients with bradycardia and angina.
- Assessment of combined beta-blocker therapy and cardiac pacing in 14 patients with ventricular arrhythmias.
Main Results:
- Temporary pacing provided good pain control in patients with bradycardia.
- Long-term cardiac pacing yielded beneficial effects in 67% of patients up to 6 months, decreasing to 50% at 24 months.
- Combined beta-blockade and pacing controlled ventricular arrhythmias in 10 out of 14 patients.
- The combination therapy demonstrated effectiveness in managing refractory angina and arrhythmias.
Conclusions:
- Correction of bradycardia by cardiac pacing can offer long-term benefits in patients with coronary artery disease.
- The combination of beta-blockade and cardiac pacing is an effective strategy for managing refractory angina and ventricular arrhythmias in chronic coronary artery disease.
- Minimizing cardiac sympathetic activity with beta-blockers and maintaining chronotropic control with pacing represents a valuable therapeutic approach.
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.