A pair of carotid arteries course through the neck and supply the majority of blood to the brain. Narrowing of these arteries can increase the risk of stroke.
There are currently two therapies for this problem. Traditionally, a surgeon operates on the neck, exposes the artery, temporarily clamps it off and removes the diseased lining before closing the artery and re-establishing blood flow (endarterectomy). However, carotid stenting has proven to be an alternative therapy. This involves placing a metal scaffold within the artery to keep it open. In some instances carotid stenting may be the preferred treatment. Carotid stenting also has the advantage in that it can be performed with the patient completely awake thus obviating the risk of anaesthetic; it is also less traumatic with a smaller incision, with less resultant risk of local haematoma and nerve damage.
Before the procedure we will require you to start two blood thinning tablets, usually aspirin and clopidogrel, which acts on the blood constituents which normally cause clotting (platelets). Both of these drugs work in tandem to reduce the risk of clotting during the procedure and within the stent afterward (thrombosis) and thereby reduces the risk of stroke.
The procedure is performed with an anaesthetist in attendance to assist in cardiovascular control, and usually takes around one hour. A catheter is advanced from the femoral artery (at the top of the leg) or radial artery (at the wrist) to the carotid artery just below the stenosis (narrowing). A fine wire (microwire) carrying an attached umbrella-like protection device is advanced through the stenosis. This is then deployed to catch any material that enters the vessel during stent placement and vessel balloon dilatation. The narrowing may first be dilated to allow easier passage of the stent. You may feel some mild discomfort as the balloon is inflated for a short time. The metallic stent is then accurately positioned across the region of narrowing and deployed. Another balloon may then be passed within the stent to open it up further.
Complications are as described for diagnostic cerebral angiography although the risk of stroke is slightly increased due to the necessity of passing catheters and guide wires through a diseased artery and stretching the diseased artery with a balloon and stent. There are also smaller risks of affecting the heart, as well as having too much blood entering the brain, due to the brain being used to getting much less blood flow for a long time. However, all operations have potential complications, and your Interventional Neuroradiologist will discuss these with you.
For more information, we advise that you speak to your doctor, who can refer you onto a Interventional Neuroradiologist at NIISwa if appropriate.