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Patent Foramen Ovale (PFO) Closure

OverviewPFO 2

A Patent Foramen Ovale (PFO) is a small hole located in the septum (muscular wall) that separates the heart into the left and right sides. This hole is used during fetal circulation to speed up the travel of blood through the heart. Normally the hole closes at birth. If the hole does not close, this defect generally works like a flap valve, only opening during certain conditions when there is more pressure inside the chest. This increased pressure occurs when people strain while having a bowel movement, cough, or sneeze. If the pressure is great enough, blood may travel from the right atrium to the left atrium. If there is a clot or particles in the blood traveling in the right side of the heart, it can cross the PFO, enter the left atrium, and travel out of the heart and to the brain (causing a stroke) or into a coronary artery (causing a heart attack).
This defect can be treated medically via blood thinning medication, or non-surgically using an implantable AMPLATZER® PFO Occluder which will close the defect.

Why do I need PFO Closure?

PFO is the most common type of heart defect. In fact, one in four people may have a PFO to some degree, but in many cases it is not large enough to create symptoms or require any immediate treatment in childhood. Many people grow up and a lead normal life without even knowing they have a PFO.

However there are a number of harmful and life affecting conditions caused by a PFO, such as migraine headaches and it is suspected to be the cause of cryptogenic stroke.

Your doctor may recommend a PFO closure procedure if it is likely your PFO is affecting the quality of your day-to-day life. Migraine headaches are common in patients with a PFO - in many cases, closure of the PFO results in improvement of migraine symptoms. PFO is associated with an increase in stroke in about 40 percent of cases. Some common symptoms of stroke are:

  •  weakness or numbness of the face, arm or leg on one side of the body
  • loss of vision or dimming (like a curtain falling) in one or both eyes
  • loss of speech, difficulty taking or understanding what others are saying
  • sudden severe headache with no known cause
  • loss of balance, unstable walking
Patent Foramen Ovale can be detected by echocardiogram or a Transesophageal echo. In some cases the patient is asked to cough or Valsalva maneuver to increase the pressure in the right atrium. this can increase the flow of blood from left to right atrium.
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How is a PFO Closure performed?

PFO Closure is a non-surgical method of closing the hole in the atrial septum, using an implantable AMPLATZER® PFO Occluder. The procedure is conducted in an angiography suite (“cath lab”) at Mercy Angiography, which is within the Mercy Hospital at 98 Mountain Road, Epsom in Auckland. Your interventional cardiologist will be assisted by nurses and other highly trained staff. 

The foramen ovale is a flap or tunnel shaped hole in the atrial septum during fetal development that allows blood to travel through the heart without going to the lungs. When in the womb, a baby does not use his or her own lungs, receiving oxygen rich blood from the the mother through the umbilical cord. Therefore, blood can travel from the right side of the baby's heart to the left side of the heart through the foramen ovale, skipping the trip to the baby’s lungs.

This small flap-like opening normally closes shortly after birth as the pressure from the baby’s heart pushes the flap to the septal wall. If this opening does not close shortly after birth, a Patent Foramen Ovale (PFO) results. This type of defect generally works like a flap valve, only opening during certain conditions when there is more pressure inside the chest. This increased pressure occurs when people strain while having a bowel movement, cough, or sneeze. If pressure is great enough, blood may travel from the right side of  the heart to the left side through the tunnel in the septal wall. If there is clot or particles present, it can travel with the heart crossing the septal wall and entering left atrium. This increases the risk of the clots travelling out of the heart to the brain causing stroke or to the coronary artery causing a heart attack. 
AMPLATZER PFO OccluderThe PFO occluder is delivered through a catheter (a small plastic tube used to access the heart) via an incision in the groin using x-ray guidance. The physician deploys the occluder to expand each disc on either side of the defect, closing off the hole. AMPLATZER® PFO occluders for heart defect repair utilise the shape memory of Nitinol, a wire made from an alloy of nickel and titanium. Each occluder is made of a Nitinol wire mesh that is shaped into two flat discs and a middle, or “waist” to pull the discs up to the septum wall.  Polyester fabric inserts help close the hole and provide a foundation for growth of tissue over the occluder after placement.

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What will I experience during my procedure?

  • An intravenous catheter (IV line) for administration of fluids and medication will be inserted into a vein on the back of your hand or in your arm.
  • Devices to monitor your heart rate and blood pressure will be attached to your body.
  • You will be awake but lightly sedated throughout the procedure.
  • You will feel the local anaesthetic injection into the groin region, where the incision will be made to insert the catheter.
  • During your procedure a dye (contrast media) will be injected to visualise the placement of your device. You may get a warm feeling as the contrast passes through your body.
You should tell your interventional cardiologist if you are experiencing any pain during the procedure. Usually patients have little or no discomfort during this procedure. Severe pain is very rare.
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How should I prepare for my procedure?

  • Fasting: You may eat until 2 hours before admission then you should not have anything to  eat. You may continue to drink clear fluids.
  • Allergies or previous reactions to contrast (x-ray dye): Please inform Mercy Angiography staff at the time of booking your procedure if you have any known history of allergies, particularly allergies to x-ray contrast and seafood.
  • Diabetes: If you are a diabetic you should tell the Mercy Angiography staff at the time of booking. You may need to discuss your insulin dose with your cardiologist.
  • Warfarin or Coumadin: If you are taking Warfarin (a “blood thinner”) you should make this known to Mercy Angiography staff at the time of booking. It is likely that you will need to stop this medication temporarily for a few days before angiography.
  • Other usual medications: Continue these unless advised otherwise by your cardiologist
Please bring with you any medication and any recent blood test results, ultrasound results or x-rays.

On the day of your procedure, please make your way to the Mercy Hospital Reception where they will be expecting you. You will be admitted to a hospital ward and transferred to Mercy Angiography for your procedure.

For directions to the Mercy Hospital, click here.

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What happens after the procedure?

  • Following the procedure, you will go to the hospital ward to recover from sedation.
  • If there are no complications, upon the discretion of the cardiologists, patients may go home on the same day as their procedure or they may require an overnight stay in the hospital.
  • Before leaving the hospital, a chest x-ray and / or echocardiogram will be performed to ensure the device is still positioned properly.
  • Prior to your discharge the cardiologists and / or ward staff will give you guidelines or advice about resuming your normal daily activities. 
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What are the Risks & Benefits?

Potential risks include:

  • PFO closure is a common procedure and serious complications are uncommon.
  • A small amount of bruising at the catheter entry point in the groin region is relatively common. This is usually not clinically important unless it becomes painful.
  • You procedure involves a puncture in the groin region. Sometimes a "false aneurysm" or out-pouching of the groin artery deep under the skin occurs at the puncture site. This shows up as increasing pain at the puncture site. The diagnosis is made by an ultrasound test and treatment is usually by an injection.
  • Abnormal or irregular beating of the heart may occur but is usually brief and easily treated.
  • An allergic reaction to the x-ray contrast (dye) with rash or itching sometimes occurs. Exceptionally rarely a very severe life-threatening allergic reaction can occur.
  • A heart attack is a very rare complication.
  • The x-ray contrast may cause some damage to kidneys that is usually temporary. It is more common in those patients who already have damaged kidneys or who suffer from diabetes.
  • Infection is very rare.
  • If you have chest pain in hospital after the procedure you should report this. Most chest pain turns out to be unimportant.
  • Stroke or death is very rare.


  • Surgery to close your PFO is avoided. This results in a shorter hospital stay and substantially reduced recovery time.
  • You may not need life-long drug therapy to prevent strokes.
  • If you suffer from migraines, you may notice a reduction in symptoms.
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