Found in the right atrium of the heart, the fossa ovalis is an embryonic remnant of the foramen ovale

Foramen ovale (heart)

In the fetal heart, the foramen ovale , also ostium secundum of Born or falx septi, allows blood to enter the left atrium from the right atrium. It is one of two fetal cardiac shunts, the other being the ductus arteriosus...

, which normally closes shortly after birth.

In a heart specimen of a neonate, the fossa ovalis is translucent, but later in life the membrane thickens.

Clinical significance

Failure of the foramen ovale to close results in a disorder known as patent foramen ovale.

External links

- "Right atrium, internal structure, anterior view"

• Diagram UCC
• Photo/Loyola