In this heart surgery, the surgeon uses stitches to close the PFO . The foramen ovale is a hole in the wall between the left and right atria of every human fetus.This hole allows blood to bypass the fetal lungs. A patent foramen ovale (PFO) is a hole in the heart that didn't close the way it should after birth. Patent foramen ovale closure is a procedure to close a hole in the heart. We use minimally invasive approaches to treat PFO without open-chest surgery.