View source for Interventricular septum

{{Short description|Wall of tissue separating ventricles of human heart}}
{{More citations needed|date=May 2015}}
{{Infobox anatomy
| Name        = Interventricular septum
| Latin       = septum interventriculare cordis
| Image       = Gray internal structure of heart.png
| Caption     = Section of the heart showing the ventricular septum.
| Image2      = Gray467.png
| Caption2    = Interior dorsal half of heart of nearly 5 weeks old human embryo. (Labeled as 'septum inferius')
| System      =
| part_of = [[Heart]]
| Artery      = [[anterior interventricular branch of left coronary artery]] and [[Posterior interventricular artery]]
}}
[[File:Interventricular septum.png|thumb]]
The '''interventricular septum''' ('''IVS''', or '''ventricular septum''', or during development '''septum inferius''') is the stout wall separating the [[ventricle (heart)|ventricles]], the lower chambers of the [[heart]], from one another.

The interventricular septum is directed obliquely backward to the right and curved with the convexity toward the [[right ventricle]]; its margins correspond with the [[anterior interventricular sulcus|anterior]] and [[Posterior interventricular sulcus|posterior interventricular sulci]]. The lower part of the septum, which is the major part, is thick and muscular, and its much smaller upper part is thin and membraneous.<ref>{{cite web |title=Interventricular septum |url=https://www.merriam-webster.com/medical/interventricular%20septum}}</ref>

During each [[cardiac cycle]] the interventricular septum contracts by shortening longitudinally and becoming thicker.

==Structure==
[[File:2037 Embryonic Development of Heart.jpg|thumb|left|Beginning of the interventricular septum shown at 28 days]]
The interventricular septum is the stout wall separating the [[Ventricle (heart)|ventricle]]s, the lower chambers of the [[heart]], from one another.

The ventricular septum is directed obliquely backward to the right and curved with the convexity toward the [[right ventricle]]; its margins correspond with the [[anterior interventricular sulcus|anterior]] and [[posterior interventricular sulci]]. The greater portion of it is thick and muscular and constitutes the '''muscular interventricular septum'''. Its upper and posterior part, which separates the [[aortic vestibule]] from the lower part of the [[right atrium]] and upper part of the right ventricle, is thin and fibrous, and is termed the '''membranous ventricular septum'''.

===Blood supply===
The [[posterior interventricular artery]], a branch of [[right coronary artery]], supplies the posterior 1/3 of the interventricular septum. The remaining anterior 2/3 is supplied by the anterior interventricular artery, which is a septal branch of the [[left anterior descending artery]], which is a branch of [[left coronary artery]]. <ref>{{cite journal |last1=Futami |first1=C. |last2=Tanuma |first2=K. |last3=Tanuma |first3=Y. |last4=Saito |first4=T. |title=The arterial blood supply of the conducting system in normal human hearts |journal=Surgical and Radiologic Anatomy |date=1 April 2003 |volume=25 |issue=1 |pages=42–49 |doi=10.1007/s00276-002-0085-7 |pmid=12819949 |s2cid=24687834 |url=https://link.springer.com/article/10.1007/s00276-002-0085-7 |access-date=13 December 2022 |language=en |issn=1279-8517|url-access=subscription }}</ref>

==Development==
{{Main|Heart development}}
The muscular part of the interventricular septum derives from the bulboventricular flange which is developed due to differential growth of primitive ventricle and bulbous cordis. Membranous part has a neural crest origin which connects the upper free margin of the bulboventricular flange and anterior and posterior endocardial cushions of atrio ventricular canal. It also gets attached to lower border of spiral septum or the aorticopulmonary septum.

In the final stages of the heart development, the interatrial septum aligns in the same plane as the interventricular septum. The gap between the interatrial septum and interventricular septum forms the membranous part of interventricular septum. <ref name="pmid13496033">{{cite journal |vauthors=MORRIS EW |title=The interventricular septum |journal=Thorax |volume=12 |issue=4 |pages=304–312 |date=December 1957 |pmid=13496033 |pmc=1019182 |doi=10.1136/thx.12.4.304 |url=}}</ref>

==Clinical significance==
A [[ventricular septal defect]] (VSD), a hole in the interventricular septum is one of the four [[congenital heart defect|congenital defects]] of the condition of [[tetralogy of Fallot]]. A VSD can cause a [[cardiac shunt|left-to-right shunt]] of blood flow in the heart and is one of the most common of the congenital heart defects. This type of shunt is an [[acyanotic heart defect|acyanotic disorder]] that can result in [[ventricular hypertrophy]]. <ref name="Pillitteri">{{cite book |last1=Pillitteri |first1=Adele |title=Maternal & Child Health Nursing: Care of the Childbearing & Childrearing Family |url=https://books.google.com/books?id=apeLf0mPx1QC&q=acyanotic&pg=PA1207 |publisher=Lippincott Williams & Wilkins |language=en |date=2010|isbn=9781582559995 }}</ref>

The alignment of interventricular septum and interatrial septum is disturbed in various [[congenital heart disease]]s.<ref>{{Cite journal |last1=Yoo |first1=Shi-Joon |last2=Saito |first2=Mika |last3=Hussein |first3=Nabil |last4=Golding |first4=Fraser |last5=Goo |first5=Hyun Woo |last6=Lee |first6=Whal |last7=Lam |first7=Christopher Z. |last8=Seed |first8=Mike |last9=Dragulescu |first9=Andreea |date=2020-11-17 |title=Systematic Approach to Malalignment Type Ventricular Septal Defects |journal=Journal of the American Heart Association |language=en |volume=9 |issue=22 |pages=e018275 |doi=10.1161/JAHA.120.018275 |issn=2047-9980 |pmc=7763733 |pmid=33170057}}</ref>

==Additional images==
<gallery>
File:Heart normal short axis echo.svg|Heart normal short axis echo  
</gallery>

==References==
{{Reflist}}

==External links==
{{wiktionary}}
{{Commons category|ECHOpedia case 'Ventricular septum defect with right to left shunt'}}
* {{OklahomaHistology|128_06}} – "Heart and semilunar valve"

{{Heart anatomy}}
{{Development of circulatory system}}
{{Authority control}}

[[Category:Cardiac anatomy|Embryology of cardiovascular system]]