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| {{Infobox Anatomy |
| | #redirect:[[Atrioventricular node]] |
| Name = {{PAGENAME}} |
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| Latin = nodus atrioventricularis |
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| GraySubject = |
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| GrayPage = |
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| Image = Gray501.png |
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| Caption = AV node visible near bend of red line. |
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| Widths = 200px
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| Image2 = |
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| Caption2 = |
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| Precursor = |
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| System = |
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| Artery = [[atrioventricular nodal branch]] |
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| Vein = |
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| Nerve = |
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| Lymph = |
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| MeshName = |
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| MeshNumber = |
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| DorlandsPre = n_09 |
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| DorlandsSuf = 12576113 |
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| }}
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| {{SI}}
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| {{CMG}}
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| ==Overview==
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| The '''atrioventricular node''' (abbreviated '''AV node''') is an area of specialized [[biological tissue|tissue]] between the [[atrium (heart)|atria]] and the [[ventricle (heart)|ventricles]] of the [[heart]], which conducts the normal electrical impulse from the atria to the ventricles.
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| The AV node may also be (rarely) referred to as the '''''Aschoff-Tawara node'''''.<ref>{{WhoNamedIt|synd|454}}</ref>
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| ==Function==
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| The AV node receives two inputs from the atria: posteriorly via the [[crista terminalis]], and anteriorly via the interatrial [[septum]].<ref>ACC/AHA/ESC Guidelines for the Management of Patients with Atrial Fibrillation - Executive Summary ([http://www.acc.org/clinical/guidelines/atrial_fib/exec_summ/exec_afindex.htm Full text])</ref>
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| 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]].
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| 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.<ref>Campbell, N., & Reece, J. (2002). Biology. 6th ed. San Francisco: Benjamin Cummings.</ref>
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| ==Blood supply==
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| 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."
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| <div align="left">
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| <gallery heights="175" widths="175">
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| Image:Steve's Heart Illustration Final Left-Right-Node Corrected.gif|Diagram of conduction system of the heart. [http://www.a-fib.com Image courtesy of a-fib.com]
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| </gallery>
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| </div>
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| ==See also==
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| *[[Electrical conduction system of the heart]]
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| *[[Sinoatrial node]] (SA node)
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| ==References==
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| {{reflist|2}}
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| ==External links==
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| * {{SUNYAnatomyFigs|20|06|02}} - "The conduction system of the heart."
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| * {{NormanAnatomy|thoraxlesson4}} ({{NormanAnatomyFig|thoraxheartinternalner}})
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| * http://www.healthyheart.nhs.uk/heart_works/heart03.shtml
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| <br>
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| {{Heart}}
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| {{Electrocardiography}}
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| [[de:Atrioventrikularknoten]]
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| [[en:atrioventricular node]] | |
| [[es:Nódulo auriculoventricular]]
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| [[ja:房室結節]]
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| [[pl:Węzeł przedsionkowo-komorowy]]
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| [[pt:Nodo atrioventricular]]
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| [[Category:Cardiac anatomy]]
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| [[Category:Cardiology]]
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