What is the foramen ovale?
The foramen ovale (foh-RAY-mun oh-VAY-lee) is a small hole located in the septum, which is the wall between the two upper chambers of the heart (atria).
Before a baby is born, it does not use its lungs to get blood rich in oxygen. Instead, this blood comes from the mother’s placenta and is delivered through the umbilical cord. The foramen ovale makes it possible for the blood to go from the veins to the right side of the fetus’ heart, and then directly to the left side of the heart.
The foramen ovale normally closes after birth. Once it is closed, the blood flows to the lungs to get oxygen before it goes into the left side of the heart and then gets pumped to the rest of the body. The condition affects about 25% of Americans, but many do not know they have the condition.
What is a patent foramen ovale?
A patent foramen ovale (PFO) means the foramen ovale did not close at birth, so there is still an opening in the septum. In most cases, the PFO does not stay open all the time. You can think of it as a flap that opens when the pressure gets higher in the right side of the heart, such as straining during bowel movements, coughing and sneezing. If you have a PFO, this pressure can cause blood to move from the right atrium to the left atrium.
What are the risks and symptoms of patent foramen ovale?
Most patients with a PFO do not have any symptoms. But, the condition may play a role in migraine headaches and it can increase the risk of stroke, transient ischemic attack (TIA), and heart attack in some patients.
Migraine headaches
Patients with a PFO may have migraine headaches with aura. Research to see if PFO closure can cure migraines has not shown that the procedure works well enough to recommend it as a treatment. More studies are needed to know if PFO closure is an effective treatment for patients with migraines.
Stroke, transient ischemic attack and heart attack
A PFO can increase the risk of stroke, TIA and heart attack in some patients. If you have a stroke or TIA and also get diagnosed with a PFO, your doctor will order tests to know if the stroke/TIA was related to the PFO or another cause, such as atherosclerosis or atrial fibrillation. Your doctor may also recommend closing the PFO.
Symptoms of a stroke and transient ischemic attack (TIA)
- Sudden weakness or numbness in the face, arm or leg on one side of the body.
- Sudden blurred vision or trouble seeing out of one or both eyes.
- Can’t speak or trouble talking or understanding what others are saying.
- Dizziness, loss of balance, unstable walking.
- Passing out for a short time.
- Suddenly can’t move part of the body (paralysis).
How is patent foramen ovale diagnosed?
Special tests are needed to detect a PFO. These include:
- Echocardiogram (echo) – An ultrasound of the heart to check blood flow across the heart valves and chambers.
- Transesophageal echo (TEE) - A probe with a tiny camera is placed in the esophagus (swallowing/ food tube). This type of echo shows a clearer picture of the defect than a standard echo does.
- Bubble study – This is done during an echo or TEE. An IV filled with agitated saline is placed in
your arm. The saline makes bubbles the doctor watches to see if they move from one side of the heart to the other.
You may need other tests to check your heart rhythm, nervous system and conditions that increase your risk of blood clots (hypercoagulable state).
What treatments are available for patients with a patent foramen ovale?
It is important to have a thorough evaluation to determine your best plan of care. An interventional cardiologist who specializes in treatment of patients with a history of PFO, and also a neurologist (if you have had a stroke), can help you understand your treatment options.
Medication
If you have a PFO and have had a stroke or TIA, you may need to take medication to thin your blood to prevent blood clots and stroke. Your doctor will talk to you about the best medication for you.
Closure of PFO
According to recent trials, such as the RESPECT trial, PFO closure is better than medication alone to prevent another stroke in patients with a PFO who have had a stroke. However, this treatment may not help all patients. To determine the best treatment for you, have a thorough evaluation by an interventional cardiologist (and in many cases a neurologist) who specializes in caring for patients with a PFO and a history of stroke.
Follow-up care
It is important to keep your follow-up visits with your doctor to monitor your condition. Your doctor will tell you how often you need to be seen.
