Die Beta-Adrenerge blokkeermiddels

Abstract

This article explains the precise mechanism of the important group of drugs called beta-adrenergic blocking agents. The therapeutic indications and efficacy of the drugs are described. Sinister side effects are highlighted and suggestions are given for the correct selection of the most appropriate drug for the purpose intended. 1. The antihypertensive effects are probably due to a combination of pharmacological properties: - an effect on the central regulation of blood pressure - a blocking action on the adrenergic neuron or - an antirenin effect - increase in baroreceptor sensitivity - hypotension as a result of reduced cardiac output. 2. Antianhythmic effect of these drugs is a direct result of the beta 1-receptor blocking property with resultant negative inotropic, dromotropic and chronotropic influence as well as diminished automaticity. Their membrane stabilising abilities thus have no part in the antiarrhythmic result. Indications for the use of beta-blockers as antiarrhythmics are: - Supraventricular arrhythmia after infarction - atrial fibrillation that does not respond to digitalis - the Wolff-Parkinson-White syndrome - paroxysmal atrial tachycardia (although verapamil is the drug of choice) The dangers involved in the use of these drugs are disturbance at the A'V-conduction, bradycardia and heartblock. Total A-V dissociation with resultant cardiac arrest may occur.