Patent foramen Ovale (PFO) | Mayo Clinic

Symptoms

Patent foramen ovale occurs in about 1 in 4 people. Most people with the condition never know they have it. A patent foramen ovale is often discovered during tests for other health problems.

Causes

It’s unclear why the foramen ovale stays open in some people. Genetics may play a role.

Complications

A patent foramen ovale, also called a patent foramen ovale (PFO) usually doesn’t cause complications. Some people with a PFO may have other heart defects

Possible complications of patent foramen ovale may include:

• Low blood oxygen. Rarely, a patent foramen ovale can cause a significant amount of blood to go around the lungs. This lowers blood oxygen levels, a condition called hypoxemia.
• Stroke. Sometimes small blood clots in veins may travel to the heart. They may go through a patent foramen ovale and into the left side of the heart. From there, they can travel to the brain and block blood flow, causing an ischemic stroke.

Some studies have found that patent foramen ovales (PFOs) are more common in people with unexplained strokes and migraines with aura. But more research is needed. Usually, there are other reasons for these conditions. It’s often just a coincidence a person also has a PFO.

What to Know About the Symptoms of PFO (Patent Foramen Ovale) | WebMD

Are There Complications of a Patent Foramen Ovale?

Most of the time, PFO is symptomless in adults, but there are some rare complications that are associated with the condition. These include: 

• Atrial septal aneurysm. The top part of the septum—the wall between the left and right sides of the heart—can start to bulge into one or both of the atria. This is a condition that is sometimes seen with PFO.
  
• Migraines. There is no understood link between PFO and migraines, but adults with PFOs sometimes have an increased chance of having migraines — particularly ones where halos form in your vision. 
  
• Cryptogenic Strokes. This is a kind of stroke that doesn’t have another identifiable cause. People with this kind of stroke are two times more likely to have a PFO than the general population. In these cases, it’s likely a thromboembolic stroke, where a blood clot that forms elsewhere in your body such as your leg moves into your heart and through the PFO. From there, it can make its way to the brain and cause a stroke. 
  
• Platypnea orthodeoxia. This is a condition where people suffer from shortness of breath and low blood oxygen levels. If too much blood flows through the PFO, then it doesn’t reach the lungs to pick up a fresh supply of oxygen. This can leave you dizzy and short of breath, particularly when standing up. 
  
• Increased risk of decompression sickness. This complication is unique to scuba divers. Divers have to deal with a condition called decompression sickness. This happens when they rise from deep, pressurized areas too quickly. Sometimes, though, this sickness is more spontaneous, seemingly uncaused by what the diver did. In two-thirds of these cases, these divers have PFOs.  

What Is the Treatment for a Patent Foramen Ovale?

Most of the time, a patent foramen ovale doesn’t need to be treated. But there are procedures to close the opening, especially for people with PFO who are younger than age 60 and have already survived a stroke. 

The most common procedure is to insert a closure device using a thin, flexible tube that goes through your groin to your heart. Your doctor moves it into place by watching it with an echocardiogram, then closes the hole by applying pressure with the device. Open heart surgery is only used to stitch the opening closed when you need the surgery to fix another heart condition at the same time.