Endocardial cushions
Interior of dorsal half of heart from a human embryo of about thirty days.
Gray's	subject #135 512
Carnegie stage	14
Days	27
Precursor	neural crest[1]
Gives rise to	septum intermedium

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.^[2]

During development the heart starts out as a tube. As heart development continues this tube undergoes conformational changes and remodeling to eventually form the four-chambered heart. The endocardial cushions are a subset of cells found in the developing heart tube that will give rise to the heart's valves and septa critical to the proper formation of a four-chambered heart.

Contents 1 Clinical significance 2 Development 3 See also 4 References 5 External links

[edit] Clinical significance

A problem in endocardial cushion development or remodeling is thought to be associated with atrioventricular septal defect.

[edit] Development

The endocardial cushions are thought to arise from a subset of endothelial cells that undergo epithelial to mesenchymal transformation, a process whereby these cells break cell-to-cell contacts and migrate into the cardiac jelly (towards to interior of the heart tube). These migrated cells form the "swelling" seen in the heart tube that is termed endocardial cushions

Upon sectioning of the heart the atrioventricular cushions can be observed in the lumen of the atrial canal as two thickenings, one on its dorsal and another on its ventral wall. These thickenings or endocardial cushions will go on to fuse and remodel to eventually form the valves and septa of the mature adult heart.

[edit] See also

• mesenchyme

[edit] References

[edit] External links

• Embryology at Temple Heart98/heart97a/sld033
• med/670 at eMedicine
• Overview at mcgill.ca

This developmental biology article is a stub. You can help Wikipedia by expanding it. v • d • e

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.

v • d • e Prenatal development/Mammalian development of circulatory system (GA 5) Vascular Blood island Development of arteries Dorsal aorta · Aortic arches Development of veins Cardinal veins · Ducts of Cuvier Fetal circulation umbilical cord: Umbilical vein → Ductus venosus → Inferior vena cava → Heart → Pulmonary artery → Ductus arteriosus → Umbilical artery yolk sac: Vitelline veins · Vitelline arteries Heart development Primitive heart tube Truncus arteriosus · Bulbus cordis · Primitive ventricle · Primitive atrium · Sinus venosus Septa/ostia Endocardial cushions/Septum intermedium · Ostium primum · Septum primum (Ostium secundum) · Septum secundum (Foramen ovale) · Aorticopulmonary septum Other Atrial canal heart navs: anat/physio/dev, noncongen/congen/neoplasia, symptoms+signs/eponymous, proc