Overview

A patent foramen ovale (PFO) is a hole in the heart that didn't close the way it should after birth. The small flaplike opening is between the right and left upper chambers of the heart (atria).

As a baby grows in the womb, the foramen ovale (foh-RAY-mun oh-VAY-lee) is present in between the right and left top chambers of the heart (atria). It normally closes during infancy. When the foramen ovale doesn't close, it's called a patent foramen ovale.

Most people never need treatment for patent foramen ovale.