Valve of inferior vena cava

The eustachian valve of (also Eustachian valve or valve of the inferior vena cava ) is a flap-like Ausziehung at the front and middle circumference of the opening of the inferior vena cava into the right atrium.

It was named after Bartolomeo Eustachi, who described it for the first time.

In the fetal circulation, it serves to direct the blood flow in the direction of the foramen ovale to thereby cause the blood directly from the right to the left atrium, thus bypassing the prenatally not yet fully formed pulmonary circulation. With the birth and the first breaths of the newborn there is a functional closure of the foramen ovale, so that the eustachian valve loses its function in the blood circulation, but remains as a relic.

• Anatomy of the heart
• Embryology