What is Patent Foramen Ovale PFO?
The term “patent” means open. Therefore, patent foramen ovale (PFO) indicates that the foramen ovale remained open after birth.
The foramen ovale permits blood to flow directly from the right atrium to the left atrium during fetal development. The foramen ovale is a critical part of the fetal circulatory system before birth, but it is expected to close soon after the birth of a baby. Normally, when babies are born and begin to use their lungs to breathe, it causes pressure in the left side of the heart. This pressure pushes the foramen ovale closed. Approximately 1 out of every 3 or 4 people has a PFO. Frequently when babies are born with congenital heart disease, it is common for their foramen ovale to remain open.
What are the signs and symptoms of PFO?
Many people with PFO will live their life without any symptoms. PFO is frequently discovered only when a patient undergoes tests for another heart condition.
What are the risks?
Stroke. Stroke is the major potential complication of a PFO. Various studies have shown that if you have a PFO, you may be slightly more likely to have a stroke than people who don’t have a PFO.
According to the National Stroke Association, up to 25 percent of the population has a PFO but may not know it until they experience a stroke. Every year, roughly 100,000 Americans suffer PFO-related strokes.
As people age they are more likely to develop blood clots in the veins of their legs. These clots might move in the bloodstream from the legs up to the heart. If an individual has a PFO, a clot may possibly travel through the opening, from the right side of their heart to the left side. From there, the clot might make it’s way to the brain, where it could block an artery and cause a stroke.
A stroke may also be more probable in someone with a PFO if they also have an atrial septal aneurysm. This type of aneurysm is a congenital heart defect that causes the wall between the left and right atria to bulge. If the septum protrudes into either of the atria, it could cause blood clots that might travel in the bloodstream to the brain.
If a younger adult has a stroke, a PFO is likely to be the cause of the stroke. Since most young people don’t have as many risk factors for stroke from other causes. Stroke can cause the following symptoms:
- Leg numbness or weakness
- Loss of coordination
- Trouble seeing out of one eye
- Severe headache
Most strokes caused by a PFO. Even people who have a PFO frequently have strokes occur from other health issues.
Heart attack. Older individuals with a PFO may have an increased risk of heart attack because blood clots from the legs may move to the heart and into one of the coronary arteries. If the clot becomes lodged in the coronary artery, the blockage will shut off all blood flow to that section of heart muscle that is fed by the artery.
Migraine with aura. For people who have migraines with aura, these headaches can cause blurry vision and blind spots. Several studies have linked PFOs with migraines and some people with PFO have found that their migraine headaches disappear after the PFO is closed.
A PFO can cause other complications as well. These include:
- Migraine and vascular headache
- Air embolism in scuba divers
- Heart attack (rare)
- Blood clots affecting other organ systems. For example, kidney damage may happen because a clot blocks blood flow to the kidney.
How is PFO diagnosed?
Frequently, a PFO is discovered during tests for other heart-related issues. Other times, the provider may be looking for a PFO if he is looking for possible causes of a stroke. If a physician believes that a patient might have a PFO, he may order the following tests:
- Echocardiography – To investigate the structure of the heart and how it is working.
- Saline contrast study (or bubble study) – In order to watch how blood flows through the heart. How the test works; a salt solution is shaken until bubbles form. The salt solution is then injected into a vein in the patient’s arm. The bubbles will travel to the right side of the heart. Physicians then use echocardiography to see where the bubbles travel to next. If the bubbles move to the lungs, then no PFO exists. If the bubbles go to the left side of the heart, then there is most likely a PFO.
- Transesophageal echocardiography (TEE) – To view a more detailed image of how blood flows through the heart. This test may be used in conjunction with a color Doppler or a bubble study.
- Transthoracic echocardiography – This is performed on the skin of the chest to see how blood is moving through the heart.
- Transesophageal echocardiography – Ultrasound images are captured from the esophagus.
- Multidetector CT – This scan offers an alternative way to see the PFO.
- Cardiovascular MRI – This imaging study also provides one more way to visualize the PFO.
- Transcranial Doppler (TCD) – This study utilizes ultrasound to locate bubbles that pass through the heart and into the arteries that supply blood to the brain. Physicians often combine these tests with a bubble study.
How is PFO treated?
The majority of people with a PFO do not require medical treatment. Patients who do need medical treatment may take medications or have a transcatheter intervention to close the PFO. In more serious cases, surgery may be required.
Patients who have a PFO and have had a stroke or heart attack, they may require antiplatelet therapy or a blood-thinning medicine to prevent blood clots from forming.
A transcatheter intervention is commonly used to close a PFO. This procedure takes place in the cardiac catheterization lab. Transcatheter closure of a PFO is a much less invasive procedure than open heart surgery, and the patient will experience less downtime recuperating. The interventional cardiologist will insert the device into the patient’s body through a small perforation in the femoral vein and then guides the device up to the heart by using echocardiography.
When the interventional cardiologist utilizes TEE, general anesthesia will be dispensed to the patient during the procedure. The procedure usually takes approximately 30-90 minutes and necessitates a one day stay in the hospital for observation and recovery.
Sometimes surgery is performed to close a PFO. Usually, doctors only recommend surgery if patients are already having heart surgery for another issue. For instance, a child may need surgery to correct another congenital heart defect; the surgeon may elect to close the PFO in the same operation. Surgery for repairing a PFO requires opening the heart and stitching the PFO closed.
Key points about PFO
- A PFO means that you have a very small opening between the right and left atria of the heart did not close at birth. In many people, it does not close.
- Most of the time a PFO itself does not cause any symptoms.
- PFO can sometimes result in complications. The most serious of these is stroke.
- Many individuals will not need treatment if they have a PFO.
- If someone has suffered a stroke because they had a PFO; they will require treatment. Treatment could include medication, procedures, or surgery.