Atrioventricular septum

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Atrioventricular septum
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Interior of heart. (AV septum not labeled, but region is visible.)
Heart coronal xs.jpg
Coronal cross section of heart. Note how the septum between the RA and LV becomes membranous.
Details
Identifiers
Latin septum atrioventriculare
TA98 A12.1.00.016
TA2 3969
FMA 7136
Anatomical terminology

The atrioventricular septum is a septum of the heart between the right atrium (RA) and the left ventricle (LV). [1] [2]

Contents

Although the name "atrioventricular septum" implies any septum between an atrium and a ventricle, in practice the divisions from RA to RV and from LA to LV are mediated by valves, not by septa. Also, there is usually no communication between the LA and the RV.

Structure

It has a membranous and muscular part. [3]

When considering only the membranous septum, it is also known as the "atrioventricular component of the membranous septum". [4]

Development

It is formed by the union of the dorsal AV cushion and ventral AV cushion. [5] This septum divides the atrioventricular canal. [6]

Clinical relevance

In some cases, defects can be identified with an echocardiogram. [7]

Incomplete formation of the endocardial cushions can lead to atrioventricular septal defects, such as an ostium primum defect.

See also

Related Research Articles

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References

  1. "Congenital Heart Disease - When Chambers and Valves Are in Normal Sequence and Position". Archived from the original on 2011-07-19. Retrieved 2009-10-11.
  2. "Congenital Heart Disease". Archived from the original on 2009-08-28. Retrieved 2009-10-11.
  3. "Yale: Congenital Heart Disease: AV septal defects". Archived from the original on 2009-06-07. Retrieved 2009-10-11.
  4. Phelps CM, Mengshol S, Ivy DD (December 2008). "A curious isolated cystic lesion of the membranous atrioventricular septum". Cardiol Young. 18 (6): 631–4. doi:10.1017/S104795110800276X. PMC   3118089 . PMID   18950547.
  5. Fix, James D.; James D., PhD. Fix; Dudek, Ronald W. (2005). Embryology . Hagerstwon, MD: Lippincott Williams & Wilkins. pp.  35. ISBN   0-7817-5726-6.
  6. Kirby, Margaret L. (2007). Cardiac development . Oxford [Oxfordshire]: Oxford University Press. pp.  104. ISBN   978-0-19-517819-7.
  7. Croti UA, Braile DM, Hassem Sobrinho S, Godoy MF (March 2007). "Case 2/2007: left atrial isomerism in the defect of partial atrioventricular septum". Rev Bras Cir Cardiovasc. 22 (1): 125–6. doi: 10.1590/s0102-76382007000100023 . PMID   17992316.