1 What is patent foramen ovale?
- Foramen ovale
The foramen ovale is a normal opening between the upper two chambers (the right atrium and left atrium) of an unborn baby’s heart.
A fetus receives oxygen, not from its lungs, but from the mother’s oxygen-rich blood via the placenta. Oxygenated blood will get to the right atrium of the fetal heart, so the foramen ovale is a normal structure to shunt blood from the right atrium to the left atrium.
At birth, when the lungs become functional, the pulmonary vascular pressure decreases and the left atrial pressure exceeds that of the right. And the foramen ovale normally closes At birth, when the lungs become functional, the pulmonary vascular pressure decreases and the left atrial pressure exceeds that of the right. And the foramen ovale normally closes in 6 months to 12 months.
- Patent foramen ovale (PFO)
However, in some individuals, the foramen ovale did not close properly at birth, so there is still an opening in the septum. This is called a Patent Foramen Ovale (PFO).[0] In most cases, the hole is normally closed but can open under increased blood pressure. On echocardiography, shunting of blood may not be noted except when the patient coughs or sneezes.
About 25% of Americans have patent foramen ovale, but many do not know their condition. [1]
2 What causes patent foramen ovale?
As mentioned, foramen ovale is a normal structure in every fetal heart. But the cause of a patent foramen ovale (PFO) is unknown. It is concerned related to two factors:
- Genetics. Some cases show that the patent foramen ovale is hereditary, but it’s not an absolute factor.[2]
- Heart disease. [3]
3 What are the symptoms of a patent foramen ovale?
Infants with a PFO and no other heart defects do not have symptoms. Some adults with PFOs suffer from migraine headaches. Most of the time, a PFO itself causes no symptoms. Sometimes symptoms do result from the complications of a PFO, such as stroke.
4 What are the possible complications of a patent foramen ovale?
Unless there are other defects, there are no complications from a PFO in most cases. But some people with a PFO may have other diseases. Possible complications of patent foramen ovale may include: [4]
- Atrial septal aneurysm. The top part of the septum may bulge into one or both of the atria.
- Low blood oxygen. Rarely, a significant amount of 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.
- 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.
- Migraine and vascular headache. There is no understood link between PFO and migraines, but adults with PFOs sometimes have an increased chance of having migraines.
- Decompression sickness. This complication is unique to scuba divers. This happens when they rise from deep, pressurized areas too quickly. In 2/3 of these cases, these divers have PFOs.
5 How is patent foramen ovale diagnosed?
Finding out whether you have a PFO is not easy, and it’s something that isn’t usually investigated unless a patient is having symptoms like severe migraines, TIA, or stroke. Specialized testing is needed to detect a PFO. This includes: [6]
- Echocardiogram (echo) – This test is done on the skin of the chest to see how blood is moving through the heart.
- 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.
- Color Flow Doppler. This test is an ultrasound. It can show different colors for objects moving at different speeds and can show the directions of movement. And find bubbles that pass through the heart and into the arteries that supply blood to the brain.
- Multidetector CT. This scan offers another way to see the PFO.
- Cardiovascular MRI. This imaging test also provides another way to see the PFO.
Sometimes a healthcare provider diagnoses a PFO based on tests that were needed to diagnose some other condition.
6 How is a patent foramen ovale treated?
Most PFOs need no treatment. There will be no treatments if you have no risk factors of stroke or any history of traveling blood clots. If necessary, you may need to take medication or have surgery.
- Medication: Anticoagulation [7]
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.
> Aspirin
> Plavix (clopidogrel)
> Coumadin (warfarin)
> Warfarin
- Surgery: PFO closure
In rare cases, your doctor may recommend closing the PFO surgically.
> Closure of the PFO with a catheter-based procedure.
> Closure of the PFO during heart surgery.
The procedure to close a PFO is simple. A catheter is used to guide a special closing device to the area of the PFO. The device expands, forming a patch that covers the hole. After the procedure, you can go home the same day or the next day. The doctor may prescribe aspirin for you to take for a few months after the procedure as a precautionary measure.
Some studies have shown that closing a PFO may relieve migraines or reduce the risk of stroke in those who have already had a stroke, but the evidence is not conclusive. You need to ask your doctor what treatment plan is best for you.
7 How to manage patent foramen ovale？
Generally, your doctor may not treat your PFO directly. Instead, he or she may suggest you do something to lower your overall risk for stroke.[8]
- Eating a healthy diet
- Getting enough exercise and avoiding obesity
- Taking medicines for high blood pressure or high cholesterol, as needed
- No smoking
- Getting treatment for other health conditions that increase the risk for stroke.
- Avoid taking excess alcohol or illicit drugs
- Avoid sitting or standing in the same position for a long time to prevent getting blood clots in your legs
