atrioventricular node

Information about atrioventricular node

AV node visible near bend of red line.
Latinnodus atrioventricularis
Arteryatrioventricular nodal branch
Dorlands/Elsevier n_09/12576113
The atrioventricular node (abbreviated AV node) is an area of specialized tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles.

The AV node may also be (rarely) referred to as the Aschoff-Tawara node.[1]

Function

The AV node receives two inputs from the atria: posteriorly via the crista terminalis, and anteriorly via the interatrial septum.[2]

An important property that is unique to the AV node is decremental conduction, in which the more frequently the node is stimulated, the slower it conducts. This is the property of the AV node that prevents rapid conduction to the ventricle in cases of rapid atrial rhythms, such as atrial fibrillation or atrial flutter.

The atrioventricular node delays impulses for ~0.1 second before allowing impulses through to the His-Purkinje conduction system, which spreads impulses to the ventricular walls. The reason it is important to delay the cardiac impulse is to ensure that the atria have ejected their blood into the ventricles before the ventricles contract.[3]

Blood supply

The blood supply of the AV node is from a branch of the right coronary artery in 85% to 90% of individuals, and from a branch of the left circumflex artery in 10% to 15% of individuals. When the RCA supplies the AV node, the coronary system is said to be "right dominant," and when the AV node is supplied by the LCX, the system is "left dominant."

See also

References

1. ^ synd/454 at Who Named It
2. ^ ACC/AHA/ESC Guidelines for the Management of Patients with Atrial Fibrillation - Executive Summary (Full text)
3. ^ Campbell, N., & Reece, J. (2002). Biology. 6th ed. San Francisco: Benjamin Cummings.

External links

 •  • [ e]
Anatomy of torso, cardiovascular system: heart
Structuresatria (interatrial septum, musculi pectinati) • ventricles (interventricular septum, trabeculae carneae, chordae tendinae, papillary muscle) • valves • cusps
Regionsbase • apex • grooves (coronary/atrioventricular, interatrial, anterior interventricula, posterior interventricular) • surfaces (sternocostal, diaphragmatic) • borders (right, left)
Right heart(vena cavae, coronary sinus) → right atrium (auricle, fossa ovalis, limbus of fossa ovalis, crista terminalis, valve of the inferior vena cava, valve of the coronary sinus) → tricuspid valve → right ventricle (conus arteriosus, moderator band/septomarginal trabecula)  → pulmonary valve → (pulmonary artery and pulmonary circulation)
Left heart(pulmonary veins) → left atrium (auricle) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and systemic circulation)
Layerspericardium  (sinus) • epicardium • myocardium • endocardium • cardiac skeleton (fibrous trigone, fibrous rings)
Conduction systemCardiac pacemaker • SA node • AV node• bundle of His • Purkinje fibers
Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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Arteries are muscular blood vessels that carry blood away from the heart.[1] All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.

The circulatory system is extremely important for sustaining life.
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The atrioventricular nodal branch most frequently arises as an early branch from the right coronary artery, but occasionally the atrioventricular node receives blood from the circumflex branch of left coronary artery.
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Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
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Biological tissue is a collection of interconnected cells that perform a similar function within an organism.

The study of tissue is known as histology, or, in connection with disease, histopathology.
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In anatomy, the atrium (plural: atria) refers to a chamber or space. As such it may for example be the atrium of the lateral ventricle in the brain or, popularly, the blood collection chamber of a heart.
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In the heart, a ventricle is a heart chamber which collects blood from an atrium (another heart chamber that is smaller than a ventricle) and pumps it out of the heart.
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heart is a muscular organ responsible for pumping blood through the blood vessels by repeated, rhythmic contractions, or a similar structure in the annelids, mollusks, and arthropods.
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crista terminalis of His (Wilhelm His, Jr.). On the external aspect of the right atrium, corresponding to the crista terminalis is the sulcus terminalis.

See also

  • Sinoatrial node

External links

  • 93978682 at GPnotebook

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septum (Latin: something that encloses; plural Septa) is a partition separating two cavities or spaces. Examples include:
  • Nasal septum: the cartilage wall separating the nostrils of the human nose.

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Atrial fibrillation
Classification & external resources

The P waves, which represent depolarization of the atria, are irregular or absent during atrial fibrillation.
ICD-10 I 48.
ICD-9 427.
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Atrial flutter
Classification & external resources

ICD-10 I 48.
ICD-9 427.32

DiseasesDB 1072
MedlinePlus 000184
eMedicine med/185   Atrial flutter is an abnormal heart rhythm that occurs in the atria of the heart.
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The right coronary artery (RCA) originates above the right cusp of the aortic valve. It travels down the right atrioventricular groove, towards the crux of the heart.

At the origin of the RCA is the conus artery.
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The "LCX", or left circumflex artery (or circumflex artery, or circumflex branch of the left coronary artery) is an artery of the heart.

Course

It follows the left part of the coronary sulcus, running first to the left and then to the right, reaching nearly
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    inactivation of certain ion channels.

Electrochemical Mechanism

See main article: Cardiac action potential
Cardiac muscle has some similarities to neurons and skeletal muscle, as well as important unique properties.
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The sinoatrial node (abbreviated SA node or SAN, also called the sinus node) is the impulse generating (pacemaker) tissue located in the right atrium of the heart, and thus the generator of sinus rhythm.
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Who Named It? is an English-language dictionary of medical eponyms and the people associated with their identification. Though this is a dictionary, many eponyms and persons are presented in extensive articles with comprehensive bibliographies.
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The State University of New York Health Science Center at Brooklyn, better known as SUNY Downstate Medical Center, is an academic medical center and is the only one of its kind in the Borough of Brooklyn in New York City.
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Georgetown University is a private, Jesuit, research university, located in Washington, D.C.'s Georgetown neighborhood. Father John Carroll founded the school in 1789, though its roots extend back to 1634.
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Human anatomy is primarily the scientific study of the morphology of the adult human body.[1] It is subdivided into gross anatomy and microscopic anatomy.[1]
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Torso is an anatomical term for the central part of the many animal bodies (including that of the human) from which extend the neck and limbs. It is sometimes referred to as the trunk. The torso includes the thorax and abdomen.
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Circulatory System is a psychedelic rock musical ensemble formed by musician/painter Will Cullen Hart, and featuring Hannah Jones, Derek Almstead, Peter Erchick, John Fernandes, and Heather McIntosh.
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heart is a muscular organ responsible for pumping blood through the blood vessels by repeated, rhythmic contractions, or a similar structure in the annelids, mollusks, and arthropods.
..... Click the link for more information.
In anatomy, the atrium (plural: atria) refers to a chamber or space. As such it may for example be the atrium of the lateral ventricle in the brain or, popularly, the blood collection chamber of a heart.
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The interatrial septum is the wall of tissue that separates the right and left atria of the heart.

Development

The interatrial septum forms during the first and second months of fetal development. Formation of the septum occurs in several stages.
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musculi pectinati (pectinate muscles).

In the left atrium, the musculi pectinati, fewer and smaller than in the right auricula, are confined to the inner surface of the auricula. This is due to the embryological origin of the auricles, which are the true atria.
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In the heart, a ventricle is a heart chamber which collects blood from an atrium (another heart chamber that is smaller than a ventricle) and pumps it out of the heart.
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Interventricular septum (or ventricular septum, or during development septum inferius) is the stout wall separating the lower chambers (the ventricles) of the heart from one another.
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The trabeculae carneae (columnae carneae, or fleshy beams), are rounded or irregular muscular columns which project from the whole of the inner surface of the ventricle, with the exception of the conus arteriosus.
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The chordae tendineae, or heart strings, are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
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