Our care teams have advanced training and extensive experience diagnosing and treating Patent Foramen Ovale (PFO, Amplatzer). Patent foramen ovale (PFO) is a small hole between the upper right and left chambers (atria) of your heart.This hole may let blood flow between the atria. Most people with a patent foramen ovale don't need treatment. Background:Patent foramen ovale (PFO) is a congenital anatomical variant which is associated with strokes in young adults. A patent foramen ovale (PFO) is a hole in the heart that didn't close the way it should after birth. A patent foramen ovale (PFO) is a hole between the heart's upper chambers (the left and right atria) that failed to close after birth. The foramen ovale is a hole in the wall between the left and right atria of every human fetus. A patent foramen ovale (PFO) is a hole in the wall between the upper left and right chambers of your heart. The foramen ovale (feh-RAY-men oh-VAL-ee) is a normal opening between the upper two chambers (the right atrium and left atrium) of an unborn baby's heart.