The foramen ovale is a small opening between the 2 upper chambers of the heart (the atria). It is normally present before birth and closes in most people after birth. If the foramen ovale does not close all the way, it is called a patent foramen ovale (PFO).
The foramen ovale lets blood skip the trip to the lungs. Before birth a baby’s blood does not need to go through the lungs to pick up oxygen because the baby gets oxygen-rich blood from the mother. After birth, increased blood pressure on the left side of the heart normally forces the flap over the hole to seal it, so all of the blood then travels from the right side of the heart to the lungs.
Sometimes the flap does not seal. When this happens, the foramen ovale may open at times, and less blood will get to the lungs to pick up oxygen.
It is not known why the flap seals after birth in most people but not everyone.
If you have pulmonary hypertension, PFO may make shortness of breath much worse.
Scuba divers with PFO may be more likely to have small strokes and damage to the brain when they dive. During decompression after diving, small nitrogen bubbles may form in the blood. These bubbles may act like blood clots and cause small strokes or brain damage. Talk with your healthcare provider if you are a diver.
PFO may increase the risk of stroke, but the evidence for this is not clear. It may also be linked to migraine headaches with aura, but this also has not been proven.
A patent foramen ovale usually does not cause any symptoms. In rare cases a baby with PFO may turn blue when crying or straining to pass a bowel movement.
The best test for diagnosing a patent foramen ovale is a transesophageal echocardiogram. It uses sound waves (ultrasound) and a computer to look at your heart. During the test a small amount of fluid is injected into your veins. The fluid contains tiny bubbles that are detected by the echocardiogram. This helps your healthcare provider see how blood is flowing in the heart.
Most children with PFO do not need any treatment. The hole may need to be closed if your child’s blood oxygen levels are too low. The hole may be closed with surgery or with heart catheterization to place a device to plug the hole.
Some healthcare providers may prescribe medicine such as warfarin or aspirin to try to reduce the chance of blood clots that might cause a stroke, but the benefits of this treatment are not clear.
Your child should have regular checkups. Your child may need to have regular follow-up visits with a specialist in congenital heart disease.
Call your child’s healthcare provider if your child: