Patent Foramen Ovale (PFO)


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 as blood pressure rises in the left side of the heart after birth. Once it is closed, the blood flows to the lungs to get oxygen before it enters the left side of the heart and gets pumped to the rest of the body.

What is a Patent Foramen Ovale?

A patent foramen ovale (PFO) means the foramen ovale did not close properly at birth, so there is still an opening in the septum. In most cases, the PFO does not stay open at all times. Instead, it’s more like a flap that opens when there is higher pressure than normal in the chambers on the right side of the heart. Situations that can cause greater pressure include straining during bowel movements, coughing and sneezing. When the pressure gets high enough, blood may move from the right atrium to the left atrium.

The condition affects about 25% of Americans, but many do not know they have the condition.

Symptoms and Causes

What are the Risks and Symptoms of Patent Foramen Ovale?

Most patients with a PFO do not have any symptoms. However, the condition may play a role in migraine headaches and it increases the risk of stroke, transient ischemic attack and heart attack.

Migraine headaches

Patients with a PFO may have migraine headaches with aura. Although the migraines stop for some patients who have the PFO closed, more studies are needed to determine if closure provides relief.

Stroke, transient ischemic attack and heart attack

Patent Foramen Ovale increases the risk of transient ischemic attack (TIA), stroke and heart attack. This is because when pressure increases in the chambers on the right side of the heart, it is possible for a blood clot or solid particles in the blood to move from the right side of the heart to the left through the open PFO, and travel to the brain (which causes a TIA or stroke) or a coronary artery (which causes a heart attack). A TIA is caused by a temporary lack of blood flow to the brain. The symptoms are the same as a stroke, but last less than 24 hours.

Many times, a TIA or stroke is the first sign of a PFO. Patients younger than Age 55 who have a stroke without a known cause (cryptogenic stroke) are more likely to have a PFO. These patients are also more likely to have a deep vein thrombosis (DVT).

Patients with a PFO may also have an atrial septal aneurysm. This condition means the top portion of the septum is bulging into one or both of the atria (top chambers of the heart).

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)

Diagnosis and Tests

How is patent foramen ovale diagnosed?

Specialized testing is needed to detect a PFO. This includes:

  • 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 that 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 to test for conditions that increase your risk of blood clots (hypercoagulable state).

Management and Treatment

What treatments are available for patients with a patent foramen ovale?

If you have a PFO but do not have symptoms or any related problems, you do not need treatment. If treatment is needed, you may need to take medication or have the PFO closed.


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. These can include aspirin, Plavix (clopidogrel), or Coumadin (warfarin). Your doctor will talk to you about the best medication for you.

Closure of PFO

Closing the PFO is not proven to be better a better treatment than medication for patients who have one stroke or TIA with an unknown cause (cryptogenic).

Usually, closure is considered if you have had more than one cryptogenic stroke or TIA after you start taking blood-thinning medication.

If your doctor determines that PFO closure is the best treatment option for you, he or she will talk to you about surgery or a device to close the PFO.

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.


How to find a doctor if you have adult congenital heart disease

Doctors vary in quality due to differences in training and experience; hospitals differ in the number of services available. The more complex your medical problem, the greater these differences in quality become and the more they matter.

Clearly, the doctor and hospital that you choose for complex, specialized medical care will have a direct impact on how well you do. To help you make this choice, read more about our Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute Outcomes.

The Center for Adult Congenital Heart Disease in the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute is a specialized center involving a multi-disciplinary group of specialists, including cardiologists, cardiac surgeons and nurses from Cardiovascular Medicine, Pediatric Cardiology, Pediatric and Congenital Heart Surgery, Cardiothoracic Surgery, Diagnostic Radiology, Pulmonary, Allergy and Critical Care Medicine, and Transplantation Center, who provide a comprehensive approach to diagnosing and treating adult congenital heart disease.

Learn more about specialized teams of doctors who treat congenital heart disease.

You may also use our MyConsult second opinion consultation using the Internet.

For younger patients with congenital heart disease:

See: About Us to learn more about the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute.


If you need more information,click here to contact us, chat online with a nurse or call the Miller Family Heart, Vascular & Thoracic Institute Resource & Information Nurse at 216.445.9288 or toll-free at 866.289.6911. We would be happy to help you.

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Last reviewed by a Cleveland Clinic medical professional on 05/03/2019.


  • Darst JR, Collins KK, Miyamoto SDCardiovascular Diseases. In: Hay WW, Jr., Levin MJ, Deterding RR, Abzug MJ. eds. CURRENT Diagnosis & Treatment: Pediatrics, 22e. New York, NY: McGraw-Hill; 2013.
  • American Heart Association. About Congenital Heart Defects ( Accessed 3/12/2015.
  • Centers for Disease Control and Prevention. Facts about Congenital Heart Defects ( Accessed 3/12/2015.
  • National Heart, Lung, and Blood Institute. What are Congenital Heart Defects? ( Accessed 3/12/2015.
  • Hirsh JC, Devaney EJ, Ohye RG, Bove EL. Chapter 19B. The Heart: II. Congenital Heart Disease. In: Doherty GM. eds. CURRENT Diagnosis & Treatment: Surgery, 13e. New York, NY: McGraw-Hill; 2010.

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