Efferent vagal innervation of the canine atria and sinus and atrioventricular nodes

The third fat pad

Chuen Wang Chiou, John Eble, Douglas P. Zipes

Research output: Contribution to journalArticle

252 Citations (Scopus)

Abstract

Background: The purpose of this study was to investigate the functional pathways of efferent vagal innervation to the atrial myocardium and sinus and atrioventricular (AV) nodes. Methods and Results: Using vagally induced atrial effective refractory period shortening, slowing of spontaneous sinus rate, and prolongation of AV nodal conduction time as end points of vagal effects, we determined the actions of phenol and epicardial radiofrequency catheter oblation (RFCA) applied to different sites at or near the atrial myocardium to inhibit these responses. We found that efferent vagal fibers to the atria are located both subepicardially and intramurally or subendocardially. Most efferent vagal fibers to the atria appear to travel through a newly described fat pad located between the medial superior vena cava and aortic root (SVC-Ao fat pad), superior to the right pulmonary artery, and then project onto two previously noted fat pads at the inferior vena cava-left atrial junction ([VC-LA fat pad) and the right pulmonary vein atrial junction (RPVfat pad) and to both atria. A few vagal fibers may bypass the SVC-Ao fat pad and go directly to the IVC-LA or RPV fat pad and then innervate the atrial myocardium. Vagal fibers to the sinus and AV nodes also converge at the SVC-Ao fat pad (a few fibers to the sinus node go directly to the RPV fat pad) before projecting to the RPV and IVC-LA fat pads. Long-term vagal denervation of the atria and sinus and AV nodes can be produced by RFCA of these fat pads and results in vagal denervation supersensitivity. Vagal denervation prevents induction of atrial fibrillation in this model. Conclusions: The newly described SVC-Ao fat pad receives most of the vagal fibers to the atria and sinus and AV nodes. Elimination of the fat pads with RFCA selectively vagally denervated the atria and sinus and AV nodes.

Original languageEnglish
Pages (from-to)2573-2584
Number of pages12
JournalCirculation
Volume95
Issue number11
StatePublished - 1997
Externally publishedYes

Fingerprint

Atrioventricular Node
Sinoatrial Node
Canidae
Adipose Tissue
Denervation
Myocardium
Catheters
Efferent Pathways
Superior Vena Cava
Pulmonary Veins
Inferior Vena Cava
Phenol
Atrial Fibrillation
Pulmonary Artery

Keywords

  • atrioventricular node
  • atrium
  • sinoatrial node
  • vagus nerve

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Cite this

Efferent vagal innervation of the canine atria and sinus and atrioventricular nodes : The third fat pad. / Chiou, Chuen Wang; Eble, John; Zipes, Douglas P.

In: Circulation, Vol. 95, No. 11, 1997, p. 2573-2584.

Research output: Contribution to journalArticle

Chiou, Chuen Wang ; Eble, John ; Zipes, Douglas P. / Efferent vagal innervation of the canine atria and sinus and atrioventricular nodes : The third fat pad. In: Circulation. 1997 ; Vol. 95, No. 11. pp. 2573-2584.
@article{9d0d016c103848519bcbac6d90235383,
title = "Efferent vagal innervation of the canine atria and sinus and atrioventricular nodes: The third fat pad",
abstract = "Background: The purpose of this study was to investigate the functional pathways of efferent vagal innervation to the atrial myocardium and sinus and atrioventricular (AV) nodes. Methods and Results: Using vagally induced atrial effective refractory period shortening, slowing of spontaneous sinus rate, and prolongation of AV nodal conduction time as end points of vagal effects, we determined the actions of phenol and epicardial radiofrequency catheter oblation (RFCA) applied to different sites at or near the atrial myocardium to inhibit these responses. We found that efferent vagal fibers to the atria are located both subepicardially and intramurally or subendocardially. Most efferent vagal fibers to the atria appear to travel through a newly described fat pad located between the medial superior vena cava and aortic root (SVC-Ao fat pad), superior to the right pulmonary artery, and then project onto two previously noted fat pads at the inferior vena cava-left atrial junction ([VC-LA fat pad) and the right pulmonary vein atrial junction (RPVfat pad) and to both atria. A few vagal fibers may bypass the SVC-Ao fat pad and go directly to the IVC-LA or RPV fat pad and then innervate the atrial myocardium. Vagal fibers to the sinus and AV nodes also converge at the SVC-Ao fat pad (a few fibers to the sinus node go directly to the RPV fat pad) before projecting to the RPV and IVC-LA fat pads. Long-term vagal denervation of the atria and sinus and AV nodes can be produced by RFCA of these fat pads and results in vagal denervation supersensitivity. Vagal denervation prevents induction of atrial fibrillation in this model. Conclusions: The newly described SVC-Ao fat pad receives most of the vagal fibers to the atria and sinus and AV nodes. Elimination of the fat pads with RFCA selectively vagally denervated the atria and sinus and AV nodes.",
keywords = "atrioventricular node, atrium, sinoatrial node, vagus nerve",
author = "Chiou, {Chuen Wang} and John Eble and Zipes, {Douglas P.}",
year = "1997",
language = "English",
volume = "95",
pages = "2573--2584",
journal = "Circulation",
issn = "0009-7322",
publisher = "Lippincott Williams and Wilkins",
number = "11",

}

TY - JOUR

T1 - Efferent vagal innervation of the canine atria and sinus and atrioventricular nodes

T2 - The third fat pad

AU - Chiou, Chuen Wang

AU - Eble, John

AU - Zipes, Douglas P.

PY - 1997

Y1 - 1997

N2 - Background: The purpose of this study was to investigate the functional pathways of efferent vagal innervation to the atrial myocardium and sinus and atrioventricular (AV) nodes. Methods and Results: Using vagally induced atrial effective refractory period shortening, slowing of spontaneous sinus rate, and prolongation of AV nodal conduction time as end points of vagal effects, we determined the actions of phenol and epicardial radiofrequency catheter oblation (RFCA) applied to different sites at or near the atrial myocardium to inhibit these responses. We found that efferent vagal fibers to the atria are located both subepicardially and intramurally or subendocardially. Most efferent vagal fibers to the atria appear to travel through a newly described fat pad located between the medial superior vena cava and aortic root (SVC-Ao fat pad), superior to the right pulmonary artery, and then project onto two previously noted fat pads at the inferior vena cava-left atrial junction ([VC-LA fat pad) and the right pulmonary vein atrial junction (RPVfat pad) and to both atria. A few vagal fibers may bypass the SVC-Ao fat pad and go directly to the IVC-LA or RPV fat pad and then innervate the atrial myocardium. Vagal fibers to the sinus and AV nodes also converge at the SVC-Ao fat pad (a few fibers to the sinus node go directly to the RPV fat pad) before projecting to the RPV and IVC-LA fat pads. Long-term vagal denervation of the atria and sinus and AV nodes can be produced by RFCA of these fat pads and results in vagal denervation supersensitivity. Vagal denervation prevents induction of atrial fibrillation in this model. Conclusions: The newly described SVC-Ao fat pad receives most of the vagal fibers to the atria and sinus and AV nodes. Elimination of the fat pads with RFCA selectively vagally denervated the atria and sinus and AV nodes.

AB - Background: The purpose of this study was to investigate the functional pathways of efferent vagal innervation to the atrial myocardium and sinus and atrioventricular (AV) nodes. Methods and Results: Using vagally induced atrial effective refractory period shortening, slowing of spontaneous sinus rate, and prolongation of AV nodal conduction time as end points of vagal effects, we determined the actions of phenol and epicardial radiofrequency catheter oblation (RFCA) applied to different sites at or near the atrial myocardium to inhibit these responses. We found that efferent vagal fibers to the atria are located both subepicardially and intramurally or subendocardially. Most efferent vagal fibers to the atria appear to travel through a newly described fat pad located between the medial superior vena cava and aortic root (SVC-Ao fat pad), superior to the right pulmonary artery, and then project onto two previously noted fat pads at the inferior vena cava-left atrial junction ([VC-LA fat pad) and the right pulmonary vein atrial junction (RPVfat pad) and to both atria. A few vagal fibers may bypass the SVC-Ao fat pad and go directly to the IVC-LA or RPV fat pad and then innervate the atrial myocardium. Vagal fibers to the sinus and AV nodes also converge at the SVC-Ao fat pad (a few fibers to the sinus node go directly to the RPV fat pad) before projecting to the RPV and IVC-LA fat pads. Long-term vagal denervation of the atria and sinus and AV nodes can be produced by RFCA of these fat pads and results in vagal denervation supersensitivity. Vagal denervation prevents induction of atrial fibrillation in this model. Conclusions: The newly described SVC-Ao fat pad receives most of the vagal fibers to the atria and sinus and AV nodes. Elimination of the fat pads with RFCA selectively vagally denervated the atria and sinus and AV nodes.

KW - atrioventricular node

KW - atrium

KW - sinoatrial node

KW - vagus nerve

UR - http://www.scopus.com/inward/record.url?scp=0030984922&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030984922&partnerID=8YFLogxK

M3 - Article

VL - 95

SP - 2573

EP - 2584

JO - Circulation

JF - Circulation

SN - 0009-7322

IS - 11

ER -