PMID: 1188164Jan 1, 1975Paper

Role of sympathetic excitation in generating arrhythmias in early and late phases of ectopic responses after coronary arterial occlusion in dog heart.

Recent Advances in Studies on Cardiac Structure and Metabolism
A S HarrisH Otero

Abstract

The three phases of arrhythmias that develop within specific durations of occlusion of a coronary artery of the dog have been reviewed and characterized. The intravenous administration of practolol as described has virtually prevented the occurrence of arrhythmic activity during the first 7-8 hr after occlusion and kept the frequency at a much reduced level as compared with controls through 10 or 11 hr, but not appreciably longer. This means that first and second phase arrhythmias were almost abolished, and development of third phase ventricular tachycardia was significantly retarded, but not prevented. It is concluded that sympathetic stimulation is an important component in the effective excitation of ectopic activity during the first and second phases, but contributed no more than a minor component to the fully developed third phase activity.

Related Concepts

Related Feeds

Atrial Fibrillation

Atrial fibrillation is a common arrhythmia that is associated with substantial morbidity and mortality, particularly due to stroke and thromboembolism. Here is the latest research.

Arrhythmia

Arrhythmias are abnormalities in heart rhythms, which can be either too fast or too slow. They can result from abnormalities of the initiation of an impulse or impulse conduction or a combination of both. Here is the latest research on arrhythmias.