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, but most often closes shortly after being born. PFO is what the hole is called when it fails to close naturally after a baby is born.
A foramen ovale allows blood to go around the lungs. A baby's lungs are not used when it grows in the womb, so the hole does not cause problems in an unborn infant.
The opening is supposed to close soon after birth, but sometimes it does not. In about 1 out of 4 people, the opening never closes. If it does not close, it is called a PFO.
The cause of a PFO is unknown. There are no known risk factors.
Infants with a PFO and no other heart defects do not have symptoms.
Exams and Tests
An echocardiogram can be done to diagnose a PFO. If the PFO is not easily seen, a cardiologist can perform a "bubble test." Saline solution (salt water) is injected into the body as the cardiologist watches the heart on an ultrasound (echocardiogram) monitor. If a PFO exists, tiny air bubbles will be seen moving from the right to left side of the heart.
This condition is not treated unless there are other heart problems, or the person had a stroke caused by a blood clot to the brain.
Treatment most often requires a procedure called cardiac catheterization, which is performed by a trained cardiologist to permanently seal the PFO.
An infant who has no other heart defects will have normal health and life span.
Unless there are other defects, there are no complications from a PFO in most cases.
Very rarely, people with PFOs may have a higher rate of a certain type of stroke (called paradoxical thromboembolic stroke). In a paradoxical stroke, a blood clot that develops in a vein (often leg veins) breaks free and travels to the right side of the heart. Normally, this clot would then continue to the lungs, but in someone with a PFO, the clot could pass through the hole to the left side of the heart. It may then be pumped out to the body, travel to the brain and become stuck there, preventing blood flow to that part of the brain (stroke).
Some people may take medicines to prevent blood clots.
When to Contact a Medical Professional
Call your health care provider if your baby turns blue when crying or having a bowel movement. Usually, this disorder is only discovered when a cardiologist performs an echocardiogram (ultrasound of the heart) for an unrelated heart murmur.
PFO; Congenital heart defect - PFO
Ferri FF. Patent foramen ovale. In: Ferri FF, ed. Ferri's Clinical Advisor 2016. Philadelphia, PA: Elsevier; 2016:935.
Webb GD, Smallhorn JF, Therrien J, Redington AN. Congenital heart disease. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 62.
Review Date 10/22/2015
Updated by: Larry A. Weinrauch, MD, Assistant Professor of Medicine, Harvard Medical School, Cardiovascular Disease and Clinical Outcomes Research, Watertown, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.