Our Adult Congenital Heart Center in New York City is a pioneer in the treatment of stroke-related patent foramen ovale. Call today 212-305-6936.PFO is a flap-like opening in the heart between the upper chambers. The foramen ovale is a structure in the wall of the heart between the two upper chambers. The healthcare provider inserts the catheter through a blood vessel in the groin and guides it to the PFO. If you have a PFO and low blood oxygen levels or an unexplained stroke, you may need a procedure to close the hole. Patent foramen ovale (PFO) is a hole between your heart's upper chambers. 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. The foramen ovale is a hole in the wall between the left and right atria of every human fetus.