The electrical activity of the bundle of His

Alanís, J; Gonzalez, H. Sanchez; López, Enrique

doi:10.1113/jphysiol.1958.sp006003

Cited by 134 publications

(38 citation statements)

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“…The electrical activity recorded from the His bundle appeared as a rapid biphasic or triphasic deflection occurring at the same point of the P-R interval (± 3.0 msec) in several successive cardiac cycles. Furthermore, the configuration and temporal relationships of these deflections are the same as that obtained in experimental studies in which placement of recording electrodes on the His bundle was performed by direct visualization during cardiotomy.2 9 Although the amplitude of the deflection varied slightly throughout the recording period, the general configuration did not change. The amplitude variation was probably due to the slight catheter movement resulting from cardiac contraction.…”

Section: Methodsmentioning

confidence: 48%

Catheter Technique for Recording His Bundle Activity in Man

et al. 1969

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A technique for the routine recording of His bundle (H) activity in man using a bipolar or multipolar catheter is described. The recording catheter is inserted percutaneously, via the Seldinger method, into the right femoral vein and advanced fluoroscopically into the right atrium. Placement of the pre-formed curve at the catheter tip across the tricuspid valve in nine patients resulted in stable recordings of His bundle activity in successive cardiac cycles. Right atrial pacing resulted in progressive lengthening of the P-H interval with increasing frequency but the H to S-wave interval remained constant at all rates. Similar lengthening of the P-H interval was produced during atrial pacing when pressure was applied to the carotid sinus. The use of this recording technique in man will facilitate diagnostic interpretation of the electrocardiogram and can be used in various investigations of atrioventricular and intraventricular conduction in man.

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Section: Methodsmentioning

confidence: 48%

Catheter Technique for Recording His Bundle Activity in Man

et al. 1969

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“…Given a diameter of Purkinje fibers of 50 J.Lm and of 7 J.Lm for an A Vnodal cell, the ratio of conduction velocities, if these were only determined by cell diameter, would be 2.7. The actual ratio [2][3][4] mis for Purkinje fibers, 5 cm I s for A V node (58)] is much larger: 40 to 80.…”

Section: A Fiber Diametermentioning

confidence: 99%

“…There are only a few studies in which extracellular electrodes were used to record directly from the AV node (4,5,47,150,161,170,187). The interpretation of most extracellular waveforms recorded from the nodal area is very difficult.…”

Section: B Pattern Of E Xcitation Ofthe a V Nodementioning

confidence: 99%

Morphology and electrophysiology of the mammalian atrioventricular node

Meijler

Janse

1988

Physiological Reviews

204

146

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The AV node of those mammalian species in which it has been thoroughly investigated (rabbit, ferret, and humans) consists of various cell types: transitional cells, midnodal (or typical nodal cells), lower nodal cells, and cells of the AV bundle. There are at least two inputs to the AV node, a posterior one via the crista terminalis and an anterior one via the interatrial septum, where atrial fibers gradually merge with transitional cells. The role of a possible third input from the left atrium has not been investigated. Since the transition from atrial fibers to nodal fibers is gradual, it is very difficult to define the "beginning" of the AV node, and gross measurements of AV nodal length may be misleading. Histologically, the "end" of the AV node is equally difficult to define. At the site where macroscopically the AV node ends, at the point where the AV bundle penetrates into the membranous septum, typical nodal cells intermingle with His bundle cells. A conspicuous feature, found in all species studied, is the paucity of junctional complexes, most marked in the midnodal area. The functional counterpart of this is an increased coupling resistance between nodal cells. An electrophysiological classification of the AV nodal area, based on transmembrane action potential characteristics during various imposed atrial rhythms (rapid pacing, trains of premature impulses), into AN (including ANCO and ANL), N, and NH zones has been described by various authors for the rabbit heart. In those studies in which activation patterns, transmembrane potential characteristics, and histology have been compared, a good correlation has been found between AN and transitional cells, N cells and the area where transitional cells and cells of the beginning of the AV bundle merge with midnodal cells, and NH cells and cells of the AV bundle. Dead-end pathways correspond to the posterior extension of the bundle of lower nodal cells and to anterior overlay fibers. During propagation of a normal sinus beat, activation of the AN zone accounts for at least 25% of conduction time from atrium to His bundle, the small N zone being the main source of AV nodal delay. Cycle length-dependent conduction delay is localized in the N zone. Conduction block of premature atrial impulses can occur both in the N zone and in the AN zone, depending on the degree of prematurity. Several factors determining AV nodal conduction delay have been identified.(ABSTRACT TRUNCATED AT 400 WORDS)

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“…As it has been reported that the refractory period of the intraventricular specialized conduction system is maximal at a level between the bundle of His and the ventricular myocardium, 12 it is obvious that time intervals recorded at the atrial and ventricular surfaces may not provide an accurate estimate of the time course of impulse propagation within the node. Accordingly, the present study was undertaken, utilizing a modification of the open heart preparation described by Alanis et al, 13 in order to appraise as closely as possible the role of the A-V node itself in the reciprocal propagation of impulses. Driving and premature stimuli, applied directly to the bundle of His, permitted the earliest possible premature penetration of the node; records of responses at the atrial margin of the node and at the His bundle defined the time attributable to intranodal transit.…”

mentioning

confidence: 99%

Some Characteristics of Ventricular Echoes

Méndez

Han

Jalon

et al. 1965

Circulation Research

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Reciprocal responses (ventricular "echoes") were initiated by premature stimuli applied directly to the bundle of His in dog hearts perfused from donor animals. The time relations of the responses in the His bundle and at the atrial margin of the exposed A-V node were studied under a number of conditions. It was found that: 1. The earliest premature response that can be induced in the His bundle is not propagated back to the atrium and does not lead to an echo. 2. There is, in most hearts, a continuous range of H 1 H 2 intervals (the echo "zone") within which reciprocal responses of the His bundle occur. 3. The earliest effective H 2 propagates slowly to the atrium, and the echo returns quickly. 4. The latest effective H 2 responses propagate more quickly to the atria, but return more slowly. 5. The atrium is an essential link in the echo pathway; i.e., the H 2 response must reach and activate the atrium before a return is possible. 6. Direct stimulation of the atrium in advance of the expected arrival of the A 2 response propagated from the His bundle can initiate a response which propagates to the bundle; i.e., two responses can travel in opposite directions on a collision course, yet one of them can complete its journey. 7. The limiting parameter of the return pathway is the refractory period of that portion of the lower node which must fire twice in the echo circuit. 8. The limiting element is not the bundle of His. 9. The limiting element can be discharged by early H 2 responses which fail to reach the atrium. 10. The refractory period of the limiting element is a function of the preceding cycle length. It was also demonstrated that the echo "zone" is shifted to a range of longer H 1 H 2 intervals when the basic driving frequency is increased, or when the vagi are stimulated. Epinephrine shifts the echo zone to a range of briefer H 1 H 2 intervals. It is suggested that echo responses occur when a retrograde impulse is arrested at one site within the node and continues to propagate to the atrium through collateral pathways. If the retrograde propagation time is long enough to permit the recovery of the lower elements of the node, an echo response reaches the His bundle. It was concluded that a self-sustained repetitive circuit may be possible when the round-trip conduction time exceeds the refractory period of the limiting tissue in the node.

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The electrical activity of the bundle of His

Cited by 134 publications

References 1 publication

Catheter Technique for Recording His Bundle Activity in Man

Catheter Technique for Recording His Bundle Activity in Man

Morphology and electrophysiology of the mammalian atrioventricular node

Some Characteristics of Ventricular Echoes

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