During development, prior to birth, a channel between the right and left sides of the heart called the foramen ovale, allows blood to bypass the lungs. In about 33% of people, the foramen ovale does not close completely, creating a “patent foramen ovale”.

This page is for patients who have previously suffered a stroke that was from an unknown cause (also called “cryptogenic stroke”) and also have an opening in their heart between the two upper chambers of the heart that never fully closed after birth. The medical term for this opening in the heart is patent foramen ovale (PFO). The information will help you learn more about cryptogenic stroke, PFO, and treatments to reduce the chance of having another stroke. You should consult with a doctor regarding the diagnosis or treatment of your medical condition.


At age 37, Alan went from being a healthy, active individual to having a stroke. Learn how the Amplatzer™ PFO Occluder eased his fears of suddenly having another stroke to living an energetic, hopeful life.


During development, prior to birth, a channel between the right and left sides of the heart called the foramen ovale, allows blood from veins to bypass the lungs. In about 33% of people, the foramen ovale does not close completely after birth. When the foramen ovale remains open, it is called a “patent foramen ovale” or a PFO. Typically, a PFO causes no problems. However, in some cases, it can allow a small amount of blood to pass from the right side of the heart to the left side of the heart.

Figure 1Figure 2Figure 3

This diagram shows an open foramen ovale before birth, a closed foramen ovale after birth, and a patent foramen ovale after birth.

Stroke Overview


Strokes are caused by a sudden interruption in blood flow to a part of the brain or bleeding within the brain tissue. When this happens, brain cells are deprived of oxygen and begin to die, causing brain damage. When brain cells die during a stroke, the function controlled by that part of the brain, like speech or movement, may be impaired.

There are two major types of stroke: hemorrhagic stroke and ischemic stroke. A hemorrhagic stroke occurs when damaged blood vessels in the brain allow bleeding into the brain tissue resulting in swelling and pressure that damages the brain. An ischemic stroke occurs when a blockage develops in a blood vessel carrying blood to the brain.


A cryptogenic stroke is an ischemic stroke for which no definite cause is found. It is estimated that 25% to 30% of ischemic strokes are cryptogenic.

One possible factor that may have contributed to your cryptogenic stroke is the presence of a Patent Foramen Ovale.


Blood clots can develop in your veins for various reasons and travel to the right side of the heart. Normally, they are then pumped to the lungs, which act as a filter. However, a PFO can allow those clots to bypass the lungs and cross to the left side of the heart. From there, they can be pumped to the brain, causing a stroke.

Patients who have a PFO and have had a cryptogenic stroke may be at an increased risk for having a second stroke. In some patients, a second stroke can be prevented by having the PFO closed.



If you have had a cryptogenic stroke and have also been diagnosed with a PFO, PFO closure with the Amplatzer PFO Occluder is a treatment option to reduce the risk of another stroke. After discussing the benefits and risks with your doctor, you can decide which treatment option is right for you. Treatments include:


Your doctor may prescribe blood-thinning medication to reduce your chance of having blood clots. Aspirin (taken daily) is the recommended medication for most patients to reduce the risk of having another ischemic stroke. Some physicians recommend stronger blood-thinning medications called anticoagulants.


Most open heart surgeries are performed through an incision across the full length of the breastbone or sternum. Open heart surgeries require the use of a heart-lung machine which takes over the function of the heart temporarily. Today, open heart surgery is rarely performed to close a PFO.


The Amplatzer PFO Occluder is a device that can be placed in your heart to close the PFO through a minimally invasive, catheter-based technique, and is designed to stop blood flow through the PFO.


The fear of having another stroke can be overwhelming. With the Amplatzer PFO Occluder, your doctor may be able to significantly reduce the risk of stroke recurrence. Researched extensively in clinical trials, the Amplatzer PFO Occluder has shown up to a 97% relative risk reduction for recurrent ischemic stroke when compared to medical management therapy.1

With a proven track record of more than 100,000 devices implanted globally over 20 years2, the Amplatzer PFO Occluder is relied upon by thousands of physicians around the world.

The Amplatzer PFO Occluder is a device specifically designed to stop blood flow through a PFO, reducing your risk of a recurring cryptogenic stroke. The device consists of two circular wire-mesh discs covered in a medical fabric that sandwich together to close the PFO between the two upper chambers in your heart (the left atrium and right atrium).

The wire mesh material can be collapsed down to fit a small tube (catheter) which is used to position the device during the procedure. Once the device is placed in the PFO, it will remain permanently implanted in your heart. Over time, the body’s natural healing process will cover the device with tissue.



    Before implantation of the Amplatzer PFO Occluder, other potential causes for your past stroke should be ruled out by your neurologist and cardiologist. If no cause is identified for your stroke (that is, you have had a cryptogenic stroke) and you have been determined to have a PFO, this team of doctors may recommend the Amplatzer PFO Occluder for you.

    Before undergoing PFO closure, your doctors will also evaluate specific factors that need to be considered for the implantation procedure itself including:

    • Your overall medical status
    • Suitability of your vessels and heart size and shape for the catheter-based procedure
    • Your suitability for general or local anesthesia
    • Your suitability to have ultrasound imaging of the heart
    • Your suitability for radiation exposure during the procedure that is necessary to implant the Amplatzer PFO Occluder

    Be sure to talk with your doctor about any medication you may be taking. He/she might advise you to adjust your medications prior to the procedure. Your doctor may tell you not to eat or drink anything after midnight prior to the procedure. You should plan on making arrangements for a ride to and from the hospital, and arrange for help at home (if necessary) after the procedure.


    The PFO closure procedure will take place in a heart catheterization laboratory, where minimally invasive procedures are performed. Before beginning the procedure, you will receive a sedating medication to help you relax and local anesthetic so that you do not feel any significant discomfort. The catheter-based procedure involves making a very small skin incision (cut), typically in the right groin area, and inserting a small tube (called a catheter) to guide the Amplatzer PFO Occluder through the blood vessels to close the PFO within your heart.

    Once the device is placed across the PFO, the cardiologist will carefully study its position using cardiac imaging tools. When the cardiologist is satisfied with the position of the Amplatzer PFO Occluder, the device will be released to remain permanently in the heart, all catheters will be removed and the implant procedure is complete. The procedure should last between one and two hours.


    After the procedure, your medical team will discuss an after-care plan with you, and you should expect to be discharged from the hospital within 24 hours. Before you are discharged from the hospital, you will receive a patient identification card. You will be prescribed aspirin (81 to 325 mg) and clopidogrel (75 mg) to be taken daily for one month after the implant procedure, followed by daily aspirin (81 to 325 mg) alone for at least five additional months. Your doctor may prescribe additional medication (typically aspirin daily) beyond six months. You will have an echocardiogram at six months so that your doctor can make sure that your device is properly implanted.

    Regular check-ups with your doctor are very important. Call or see your doctor whenever you have questions or concerns about your health. If you have any unusual problems such as bleeding, pain, other discomfort or changes in your overall health, be sure to contact your doctor.

    Always carry your Amplatzer PFO Occluder implant card and tell other doctors that you have a PFO closure device before any medical, dental or MRI (magnetic resonance imaging) procedures. Failure to do so may result in health problems or damage to the device.


    As with any medical procedure, there is a possibility of complications. The most serious risks of the procedure include:

    • Blood clot in the heart, leg or lung requiring long-term anticoagulation therapy
    • Blood or fluid build-up between the heart muscle and the sac that covers the heart requiring a drainage procedure
    • Death
    • Irregular and/or rapid heart rate (particularly atrial fibrillation)
    • Perforation of the heart muscle or vessels
    • Stroke (major or minor)

    Additional potential risks associated with the procedure or the device include:

    • Allergic reaction to anesthesia
    • Allergic reaction to contrast dye used to visualize heart during the implant procedure
    • Allergic reaction to a drug used during the procedure
    • Allergic metal reaction: Nitinol (nickel, titanium), platinum/iridium, stainless steel (chromium, iron, manganese, molybdenum, nickel)
    • Arrhythmia (loss of regular heart rhythm)
    • Bleeding
    • Blood clot on device
    • Blood vessel blockage due to blood clots or air
    • Chest pain
    • Fever
    • Fluid buildup around lungs
    • Headache or migraine
    • Heart attack
    • Heart valve damage that interferes with valve closure
    • High or low blood pressure
    • Incomplete closure of PFO
    • Infection
    • Injury to the heart or vessels
    • Injury to the nerves in the arm or lower neck
    • Movement of the device from its position within the PFO or to other parts of the body
    • Sudden interruption of blood flow to an organ or body part
    • Surgery or intervention to remove the device
    • Trouble or inability to breathe


    • If you are prone to venous blood clots, your doctor may prescribe a blood thinning medication (usually an anticoagulant) for at least 6 months.
    • Talk to your doctor if you are allergic to nickel. The Amplatzer PFO Occluder is made of a metal called nitinol containing nickel and titanium.


    Talk to your doctor if you are:

    • Pregnant
    • Have a history of multi-organ failure
    • Unable to take blood thinning medication

    The Amplatzer PFO Occluder should not be implanted in patients who:

    • Have a tumor or blood clots at the implantation site of the device or in the vessels through which the device is advanced to reach the heart
    • Have blood vessels too small to allow the delivery system to pass through
    • Have an anatomy in which the device would interfere with heart or vascular function
    • Have other types of heart defect
    • Have infection of the heart



1. Mas J-L, Derumeaux G, Guillon B, et al. Patent foramen ovale closure or anticoagulation vs. antiplatelets after stroke. N Engl J Med 2017;377:1011-21 and supplementary appendix.

2. Abbott (2018). Internal Sales Data 1996-2018.




The AMPLATZER™ PFO Occluder is indicated for percutaneous transcatheter closure of a patent foramen ovale (PFO) to reduce the risk of recurrent ischemic stroke in patients, predominantly between the ages of 18 and 60 years, who have had a cryptogenic stroke due to a presumed paradoxical embolism, as determined by a neurologist and cardiologist following an evaluation to exclude known causes of ischemic stroke.

  • Patients with intra-cardiac mass, vegetation, tumor or thrombus at the intended site of implant, or documented evidence of venous thrombus in the vessels through which access to the PFO is gained.
  • Patients whose vasculature, through which access to the PFO is gained, is inadequate to accommodate the appropriate sheath size.
  • Patients with anatomy in which the AMPLATZER™ PFO device size required would interfere with other intracardiac or intravascular structures, such as valves or pulmonary veins.
  • Patients with other source of right-to-left shunts, including an atrial septal defect and/or fenestrated septum.
  • Patients with active endocarditis or other untreated infections.
  • Patients who are at increased risk for venous thromboembolic events should be managed with thromboembolic risk reduction regimen after the PFO Closure following standard of care.
  • Do not use this device if the sterile package is open or damaged.
  • Prepare for situations that require percutaneous or surgical removal of this device. This includes availability of a surgeon.
  • Embolized devices must be removed as they may disrupt critical cardiac functions. Do not remove an embolized occluder through intracardiac structures unless the occluder is fully recaptured inside a catheter or sheath.
  • Patients who are allergic to nickel can have an allergic reaction to this device.
  • This device should be used only by physicians who are trained in standard transcatheter techniques.
  • Transient hemodynamic compromise may be encountered during device placement, which may require fluid replacement or other medications as determined by the physician.
  • Do not release the device from the delivery cable if the device does not conform to its original configuration, or if the device position is unstable or if the device interferes with any adjacent cardiac structure (such as Superior Vena Cava (SVC), Pulmonary Vein (PV), Mitral Valve (MV), Coronary Sinus (CS), aorta (AO)). If the device interferes with an adjacent cardiac structure, recapture the device and redeploy. If still unsatisfactory, recapture the device and either replace with a new device or refer the patient for alternative treatment.
  • Ensure there is sufficient distance from the PFO to the aortic root or SVC (typically defined as 9 mm or greater as measured by echo). See Figure 6. and Figure 7.
  • The safety and effectiveness of the AMPLATZER™ PFO Occluder has not been established in patients (with):
    • Age less than 18 years or greater than 60 years because enrollment in the pivotal study (the RESPECT trial) was limited to patients 18 to 60 years old
    • A hypercoagulable state including those with a positive test for a anticardiolipin antibody (IgG or IgM), Lupus anticoagulant, beta-2 glycoprotein-1 antibodies, or persistently elevated fasting plasma homocysteine despite medical therapy
    • Unable to take antiplatelet therapy
    • Atherosclerosis or other arteriopathy of the intracranial and extracranial vessels associated with a ≥50% luminal stenosis
    • Acute or recent (within 6 months) myocardial infarction or unstable angina
    • Left ventricular aneurysm or akinesis
    • Mitral valve stenosis or severe mitral regurgitation irrespective of etiology
    • Aortic valve stenosis (mean gradient greater than 40 mmHg) or severe aortic valve regurgitation
    • Mitral or aortic valve vegetation or prosthesis
    • Aortic arch plaques protruding greater than 4 mm into the aortic lumen
    • Left ventricular dilated cardiomyopathy with left ventricular ejection fraction (LVEF) less than 35%
    • Chronic, persistent, or paroxysmal atrial fibrillation or atrial flutter
    • Uncontrolled hypertension or uncontrolled diabetes mellitus
    • Diagnosis of lacunar infarct probably due to intrinsic small vessel as qualifying stroke event
    • Arterial dissection as cause of stroke
    • Index stroke of poor outcome (modified Rankin score greater than 3)
    • Pregnancy at the time of implant
    • Multi-organ failure
  • Use on or before the last day of the expiration month that is printed on the product packaging label.
  • This device was sterilized with ethylene oxide and is for single use only. Do not reuse or re-sterilize this device. Attempts to re-sterilize this device can cause a malfunction, insufficient sterilization, or harm to the patient.
  • The AMPLATZER™ PFO Occluder device consists of a nickel-titanium alloy, which is generally considered safe. However, in vitro testing has demonstrated that nickel is released from this device for a minimum of 60 days. Patients who are allergic to nickel may have an allergic reaction to this device, especially those with a history of metal allergies. Certain allergic reactions can be serious; patients should be instructed to notify their physicians immediately if they suspect they are experiencing an allergic reaction such as difficulty breathing or inflammation of the face or throat. Some patients may also develop an allergy to nickel if this device is implanted.
  • Store in a dry place.
  • Pregnancy – Minimize radiation exposure to the fetus and the mother.
  • Nursing mothers – There has been no quantitative assessment for the presence of leachables in breast milk.

Potential adverse events that may occur during or after a procedure using this device may include, but are not limited to:
Air embolus Allergic drug reaction; Allergic dye reaction; Allergic metal reaction: Nitinol (nickel, titanium), platinum/iridium, stainless steel (chromium, iron, manganese, molybdenum, nickel); Anesthesia reactions; Apnea; Arrhythmia; Bacterial endocarditis; Bleeding ; Brachial plexus injury; Cardiac perforation; Cardiac tamponade; Cardiac thrombus; Chest pain; Device embolization; Device erosion; Deep vein thrombosis; Death; Endocarditis; Esophagus injury; Fever; Headache/migraine; Hypertension/hypotension; Myocardial infarction; Pacemaker placement secondary to PFO device closure; Palpitations; Pericardial effusion; Pericardial tamponade; Pericarditis; Peripheral embolism; Pleural effusion; Pulmonary embolism; Reintervention for residual shunt/device removal; Sepsis; Stroke; Transient ischemic attack; Thrombus; Valvular regurgitation; Vascular access site injury; Vessel perforation