Foramen ovale

Definition

The foramen ovale is a small hole located in the septum, which is the wall between the right and left atria of the fetal heart. This opening allows blood to bypass the fetal lungs, which are not yet in use, by directly flowing from the right to the left atrium.

Related terms

Ductus arteriosus: A vessel in fetal circulation that connects the pulmonary artery to the descending aorta, allowing most of the blood from the right ventricle to bypass the fetus's non-functioning lungs.

Fetal circulation: The circulatory system in a fetus that includes unique structures (like the foramen ovale and ductus arteriosus) designed to supply oxygen and nutrients while bypassing certain organs not yet in use.

Septum: The wall dividing two chambers or cavities, such as in the heart where it separates different chambers like atria and ventricles