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About Patent Foramen Ovale (PFO)

The Foramen Ovale is a flap-like opening between the two upper chambers of the heart known as the left and right atria. In the womb, all babies have this opening because it makes circulation more efficient during development. However, after birth the flaps normally close to form a solid wall (called the septum) between the chambers. If it does not close properly at birth, it is called a Patent Foramen Ovale (PFO). A PFO can permit blood to pass unfiltered from the right atrium to the left atrium and out into the body, including the brain.

A PFO is typically closed with a minimally invasive procedure called a PFO Closure which is performed under local anaesthetic. During the procedure, a PFO closure device is implanted into your heart. This procedure is much safer than open-heart surgery and the patient experiences little discomfort. Patients are generally able to leave the hospital the following day.

What are the potential problems associated with having a PFO?

Several clinical experiences have shown a potential association between the presence of a PFO and patients who suffer migraines or have experienced a stroke of undermined cause (called a cryptogenic stroke). In fact, recent studies have found that up to 40% of Migraine sufferers have a PFO. Evidence shows that closing the PFO can decrease the frequency of migraines or reduce the risk of having a stroke.

The reason for the link between the presence of a PFO and the incidence of migraine and stroke is currently unknown. Some research suggests that the unfiltered blood that is allowed to pass into the left atrium through the PFO may trigger migraines or may cause blockage to the artery in the brain, resulting in a stroke. Active clinical trials are exploring the effects of the PFO and any befits found by closing it.

Pre-Operative Preparation


You will be asked to fast (no food or drink) for 6 hours prior to the procedure.

Medication Instruction

Your cardiologist will advise if there is to be any change to your usual medication prior to the procedure. If your doctor has advised you to take your usual medication, take this early on the morning of the procedure with just a small amount of water.


The following tests may be performed prior to or as part of the procedure:

  • Echocardiography

    Right Heart Catheter – After an injection of local anaesthetic, a soft balloon catheter is put into the vein in your groin. The tube is passed along until it reaches the heart and then goes up into the blood vessels of the lung. The pressures in the lungs and heart are recorded.

  • Coronary Angiography

  • CT Coronary Angiogram


The procedure is performed under local anaesthetic, meaning you will be awake throughout it. After a small incision is made in the groin and a long, thin tube called a catheter is inserted into a vein. The PFO closure device is then guided through the catheter to the heart. Once there the device is implanted, or anchored, and then adjusts to the unique anatomy of your heart.

Soon after the PFO closure device is implanted, tissue begins to form and eventually cover the device completely. This process of tissue formation is medically known as endothelialisation. It is important because it helps prevent blood in the left atrium from reacting with the exposed device and forming clots (called thrombosis).

Post-Operative Care

Patients are generally discharged from hospital the day after the procedure. You will be reviewed by your doctor prior to discharge. One of our staff members will be in contact with you to arrange a follow-up appointment in the rooms in the near future.