Atrioventricular septum
Encyclopedia
The atrioventricular septum is a septum of the heart between the right atrium
(RA) and the left ventricle
(LV).
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.
It has a membranous and muscular part.
When considering only the membranous septum, it is also known as the "atrioventricular component of the membranous septum".
It is formed by the union of the dorsal AV cushion and ventral AV cushion. This septum divides the atrioventricular canal.
Incomplete formation of the endocardial cushions
can lead to atrioventricular septal defect
s, such as an ostium primum defect
.
Right atrium
The right atrium is one of four chambers in the hearts of mammals and archosaurs...
(RA) and the left ventricle
Left ventricle
The left ventricle is one of four chambers in the human heart. It receives oxygenated blood from the left atrium via the mitral valve, and pumps it into the aorta via the aortic valve.-Shape:...
(LV).
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.
It has a membranous and muscular part.
When considering only the membranous septum, it is also known as the "atrioventricular component of the membranous septum".
It is formed by the union of the dorsal AV cushion and ventral AV cushion. This septum divides the atrioventricular canal.
Pathology
In some cases, defects can be identified with an echocardiogram.Incomplete formation of the endocardial cushions
Endocardial cushions
Atrioventricular cushions or endocardial cushions refers to a subset of cells in the primordial heart that play a vital role in proper heart septation.They develop on the atrioventricular canal.During development the heart starts out as a tube...
can lead to atrioventricular septal defect
Atrioventricular septal defect
Atrioventricular septal defect or atrioventricular canal defect , previously known as "common atrioventricular canal" or "endocardial cushion defect", is characterized by a deficiency of the atrioventricular septum of the heart...
s, such as an ostium primum defect
Ostium primum atrial septal defect
The ostium primum atrial septal defect is a defect in the atrial septum at the level of the tricuspid and mitral valves...
.
External links
- http://www.acc.org/membership/community/pediatric/opinion_apr03/Slide11.JPG