Patient education: Patent foramen ovale (The Basics)

What is a patent foramen ovale? — 

A patent foramen ovale, or "PFO," is a small opening inside the heart. The opening is between the upper 2 chambers of the heart, called the right atrium and left atrium (figure 1). A PFO lets blood flow between these chambers.

Before birth, when a baby is growing in the uterus, it is normal for them to have an opening between the right atrium and left atrium. The opening lets blood flow through the heart correctly. (The way blood flows through the heart before birth is different from how it flows after birth.)

After birth, the opening between the right atrium and left atrium is not needed anymore. In most babies, the opening closes on its own soon after birth. But in some babies, it does not close. This is a PFO, and it is very common. About 1 out of every 4 people has a PFO. Doctors don't know what causes it.

What are the symptoms of a PFO? — 

Most people have no symptoms or problems. Some people might find out they have it when their doctor does a test for another reason.

In some cases, a PFO can lead to problems. Although uncommon, some can lead to a stroke. This is when a part of the brain is damaged because of a problem with blood flow. It can cause problems with speaking, thinking, or moving the arms or legs.

A PFO can lead to a stroke like this: A blood clot forms in a leg vein. The clot then travels through the blood to the heart. It then enters the right atrium. If a person has a PFO, the blood clot can then flow into the left atrium. From there, it flows into the left ventricle and then to the body or brain. A blood clot that travels to the brain can cause a stroke.

Is there a test for a PFO? — 

Yes. People might have tests to check for a PFO if they have a stroke and their doctor can't find the cause.

The test most often used to check for a PFO is called an "echocardiogram," or "echo" (figure 2). It uses sound waves to create pictures of the heart as it beats.

If your doctor thinks you might have a PFO, they might order a "bubble test" with your echo. For this test, the staff will put some salt water (that has bubbles) into your vein. They do this through a thin tube called an "IV." Then, they do an echo to watch how the bubbles flow through your heart.

How is a PFO treated? — 

Treatment depends on whether your PFO causes symptoms or not.

If your PFO causes no symptoms, it does not need treatment.

If you had a stroke that could have been caused by your PFO, your doctor will talk with you about possible treatments. These might include:

●Medicines, including aspirin or other medicines to prevent blood clots

●A procedure or surgery to close the PFO

Your doctor might also recommend things you can do on your own to prevent blood clots in your legs. To help prevent blood clots in your legs, you should:

●Avoid sitting or standing still in the same position for a long time

●Stand up and walk around every 1 to 2 hours, including when you take long trips by car, train, or plane

●Change your position when you are sitting, and move your legs and feet often

●Quit smoking, if you smoke. Your doctor or nurse can help.

More on this topic

Patient education: Echocardiogram (The Basics)
Patient education: Deep vein thrombosis (blood clot in the leg) (The Basics)
Patient education: Lowering the risk of a blood clot (The Basics)
Patient education: Stroke (The Basics)
Patient education: Lowering the risk of having a stroke (The Basics)
Patient education: Atrial septal defects in children (The Basics)

Patient education: Deep vein thrombosis (DVT) (Beyond the Basics)
Patient education: Stroke symptoms and diagnosis (Beyond the Basics)