The skilled team of cardiologists at The Heart Center at Mercy Medical Center in Baltimore, Maryland provides diagnosis and treatment for patent foramen ovale. The surgeons at our adult congenital heart center perform patent foramen ovale closures and actively research innovative techniques to treat the condition.A patent foramen ovale (PFO) is a small opening between the two upper chambers of the heart, the right and the left atrium. The healthcare provider inserts the catheter through a blood vessel in the groin and guides it to the PFO. However, it may cause serious complications under certain circumstances. 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. Patent foramen ovale (PFO) is a hole between the left and right atria (upper chambers) of the heart. This hole exists in everyone before birth. Dr. Lee MacDonald from South Denver Cardiology Associates talks about holes in the heart.