Author:
Masuda M O,Paes de Carvalho A
Abstract
Intracellular microelectrodes and small unipolar leads applied to endocardial surface of the right atrium in vitro were used to study the complex extracellular wave patterns recorded from the neighborhood of the cardiac pacemaker during spontaneous activity. Sinus activity propagated slowly toward the site of atrial invasion on the venous border of the crista terminalis. Atrial activation was marked by a primary negative wave that appeared 20-40 msec after pacemaker firing. Two sources of complex multiphasic waves were found. First, potentials from transitional sinus tissue propagated toward the atrium and caused low-voltage waves that preceded and slurred the onset of the atrial initial negativity. Second, bundles and layers of the crista terminalis muscle were excited asynchronously around the invasion region, as if cross-connections were infrequent. Waves originating from this source occurred after the firing of the invasion site. No extracellular wave could be associated with the firing of the true pacemaker cells. The sinoatrial ring bundle (SARB) yielded a discrete biphasic deflection along most of its way toward the coronary sinus. This potential appeared most frequently after that of the adjoining cristal muscle, raising questions about the functional role of the SARB as an internodal preferential pathway.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Cardiology and Cardiovascular Medicine,Physiology
Reference16 articles.
1. Galvanometric curves yielded by cardiac beats generated in various areas of the auricular musculature: The pacemaker of the heart;Heart,1910
2. Sur le point d'origine de la systole cardiaque dans l'oreillette droite;Arch Int Physiol,1910
3. Form and nature of the muscular connections between the primary divisions of the vertebrate heart beat;J Anat Physiol,1907
4. THE ORIGIN AND CONDUCTION OF THE HEART BEAT
5. Normal auricular activation in the dog's heart
Cited by
33 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献