Editing Atrioventricular node (section)

==Structure==
===Location===
The AV node lies at the lower back section of the [[interatrial septum]] near the opening of the [[coronary sinus]], which conducts the normal electrical impulse from the atria to the ventricles. The AV node is quite compact (~1 x 3 x 5&nbsp;mm).<ref name="medical-dictionary.thefreedictionary.com"/> It is located at the center of [[Koch's triangle]]—a triangle enclosed by the septal leaflet of the tricuspid valve, the coronary sinus, and the membranous part of the interatrial septum.<ref>[http://www.accessmedicine.com/content.aspx?aID=2874462 Harrison's Principles of Internal Medicine, 17e" Section 3: Disorders of Rhythm] {{webarchive |url=https://web.archive.org/web/20110707080333/http://www.accessmedicine.com/content.aspx?aID=2874462 |date=July 7, 2011 }}</ref>

===Blood supply===
The blood supply of the AV node is from the [[atrioventricular nodal branch]]. The origin of this artery is most commonly (80–90% of hearts) a branch of the [[right coronary artery]], with the remainder originating from the [[left circumflex artery]].<ref name="pmid5086972">{{Cite journal|vauthors=Van der Hauwaert LG, Stroobandt R, Verhaeghe L |title=Arterial blood supply of the atrioventricular node and main bundle |journal=British Heart Journal |volume=34 |issue=10 |pages=1045–1051 |date=October 1972 |pmid=5086972 |pmc=458545 |doi=10.1136/hrt.34.10.1045}}</ref><ref>{{Cite journal | last1 = Pejković | first1 = B. | last2 = Krajnc | first2 = I. | last3 = Anderhuber | first3 = F. | last4 = Kosutić | first4 = D. | title = Anatomical aspects of the arterial blood supply to the sinoatrial and atrioventricular nodes of the human heart | journal = The Journal of International Medical Research | volume = 36 | issue = 4 | pages = 691–698 | year = 2008 | pmid = 18652764 | doi=10.1177/147323000803600410| doi-access = free }}</ref><ref>{{Cite journal | last1 = Saremi | first1 = F. | last2 = Abolhoda | first2 = A. | last3 = Ashikyan | first3 = O. | last4 = Milliken | first4 = J. C. | last5 = Narula | first5 = J. | last6 = Gurudevan | first6 = S. V. | last7 = Kaushal | first7 = K. | last8 = Raney | first8 = A. | doi = 10.1148/radiol.2461070030 | title = Arterial Supply to Sinuatrial and Atrioventricular Nodes: Imaging with Multidetector CT | journal = Radiology | volume = 246 | issue = 1 | pages = 99–107; discussion 108–109 | year = 2007 | pmid = 18024438 }}</ref> This is associated with the [[Coronary artery dominance|dominance]] of the coronary artery circulation. In ''right-dominant'' individuals the blood supply is from the right coronary artery while in left dominant individuals it originates from the left circumflex artery.

===Development===
[[Bone morphogenetic protein]] (BMP) [[cell signaling]] plays a key role in diverse aspects of cardiac differentiation and morphogenesis. (BMPs) are multifunctional signaling molecules critical for the development of AV node. BMP influences AV node development through Alk3 receptor (Activin receptor-like kinase 3). Abnormalities seen in BMP and Alk3 are associated with some cardiovascular diseases like Ebstein's anomaly and AV conduction disease.<ref>{{Cite journal|vauthors=Stroud DM, Gaussin V, Burch JB |title=Abnormal Conduction and Morphology in the Atrioventricular Node of Mice With Atrioventricular Canal–Targeted Deletion of Alk3/Bmpr1a Receptor |journal=Circulation |volume=116 |issue=22 |pages=2535–2643 |date=November 2007 |pmid=17998461|pmc=2947829 |doi=10.1161/CIRCULATIONAHA.107.696583|display-authors=etal}}</ref>