What is a stroke?

Stroke is the common term for a Cerebral Vascular Accident (CVA). A CVA occurs when blood flow to the brain is blocked or interrupted. CVAs are often classified according to the duration of symptoms. CVAs with lengthy or permanent symptoms are commonly called strokes. When symptoms last less than 24 hours, they are termed Transient Ischemic Attacks (TIA). These are often called 'mini strokes' and are equated to chest pain, or angina, in patients with heart disease. Recently, CVAs that exhibit no physical, but other symptoms such as memory loss, have been described as 'silent strokes'. Strokes are classified as hemorrhagic, occlusive, and embolic.

Embolic strokes are caused by debris such as blood clots. There are several sources of debris. Irregular heart beats can cause small clots to form in the left atrium. Valve disease and Aortic disease are a source. So are masses or tumors on the arterial (left) side of the heart. Clots also occur naturally in the veins of some people and cross into the arterial circulation, lodging in the brain. When the source of the stroke is unknown, it is commonly called "cryptogenic ", meaning hidden source. Physicians now believe some cryptogenic strokes result from a patent foramen ovale (PFO).

A Patent Foramen Ovale (PFO) is a small flap valve defect between the right atrium and the left atrium. (see diagram) This defect can be opened when people increase pressure on their chest, such as when they take a bowel movement. When the valve is opened an embolus may cross the defect. This is called a paradoxical embolus and a stroke or TIA, may result. You may have had an event like this multiple times despite taking blood thinners.

Yes, a PFO can be closed using either open heart surgery, or a new technique called transcatheter CardioSEAL closure.

How does CardioSEAL closure work?

CardioSEAL closure is performed using catheters in the heart catheterization laboratory by a Doctor. The Doctor will gain access to your heart using a major vein in the groin. Various catheters will be advanced from the groin into the heart. A test involving moving pictures of the heart, called an angiogram, may be taken to better visualize the heart and the hole. The Doctor may also use a special ultrasound procedure, called echocardiography (echo) to better see the heart and the hole. One type of echo involves putting a tube into the esophagus. Another type uses a vein to place the echo tube inside the heart. These tests are used to decide which size CardioSEAL will be used to close the hole.

How is CardioSEAL inserted?

The appropriate size CardioSEAL is attached and collapsed for placement into a special catheter. The catheter is then advanced to the hole. The Doctor re-expands the implant so that part of it sits on each side of the hole. In effect, the hole is gently sandwiched between the two sides of the implant. The implant is then released from the catheter. The catheter is removed and the procedure completed. These diagrams may help you to understand the steps of implanting the CardioSEAL Occluder. In time, new tissue grows into the implant.

Will I be awake during the procedure?

This is up to the physician. Many patients are put under general anesthesia for this procedure. A local anesthetic is used to numb the groin where the catheters are inserted.

How does the CardioSEAL stay in place?

CardioSEAL is made from two, small diameter wire frameworks. The framework has a special fabric attached to it. The implant looks like two umbrellas set edge to edge. Each umbrella framework has special springs. This allows the umbrella to spring towards the hole. This very slight tension, along with the blood in the heart, holds the device in place. Over time, tissue grows into the implant fabric becoming part of the heart.

What does CardioSEAL look like?

CardioSEAL Occluders looks like two umbrellas. It is available in several sizes for different sized PFO's. The smallest (17 mm measured diagonally) is about the size of a dime, the largest is about the size of a half-dollar. This picture shows the 33mm implant placed next to a dime. The framework is made from a metal frequently implanted in the body during other surgeries. The fabric is the same fabric the surgeon might use when open heart surgery is performed.

Will the procedure hurt?

Usually not. After the procedure, some patients report tenderness at the groin. Some also complain of a sore throat from the echo probe if this type is used. Patients cannot "feel" the implant.

What are the risks of CardioSEAL closure?

The implanting physician usually ensures that the risks associated with heart catheterization and the implant are carefully reviewed with each patient.

What is the special care after the procedure?

Bed rest for a period of time (this allows the implant to stabilize); Restriction from heavy lifting or other physical activities for a period of time; You may need to take a blood thinning product, such as Aspirin, every day, for a period of time (six months); You should take antibiotics to prevent infection for a period of time (perhaps six months or longer and when going to the dentist or having minor surgery). It is important to follow the doctor's instructions precisely and to call the doctor if there are any questions.

What about follow up visits?

All patients are asked to see their doctor for follow up visits. The Doctor will provide specific instructions for follow-up visits and care.

Does the Implant stay in for the rest of my life?

Can I go through metal detectors, or have and M.R.I.?

Yes. The implant will not set off metal detectors. The metal framework is not magnetic. It will not be affected by an MRI, but the picture taken by the MRI might have a fuzzy quality. If an MRI is needed, the MRI staff should be informed about the presence of CarioSeal.

Who is CardioSeal indicated for?

CardioSeal was approved by the FDA under humanitarian device regulations for closure of a Patent Foramen Ovale (PFO) in patients with recurrent cryptogenic stroke due to presumed paradoxical embolism through a PFO and who have failed conventional drug therapy.

This guide was prepared by NMT Medcial, Inc. as an educational aid for patients determined to be suitable candidates for treatment with CardioSEAL Septal Occluders. It is based on input and guidance from Physicians and Nurses throughout the world. NMT thanks them for their contributions. However, this guide is not a replacement for speaking with your physician. NMT Medical recommends you write down questions for your doctor on a separate piece of paper.

NMT Medical welcomes your comments about this guide and how it may be improved for the benefit of other patients. Please contact us with comments, suggestions and questions at either of our offices below.

For the name of a physician trained to use CardioSEAL for PFO closure, please visit our website at www.nmtmedical.com