Carotid artery disease is a form of disease that affects the blood vessels leading to the head and brain (cerebrovascular disease). Like the heart, the brain's cells need a constant supply of oxygen-rich blood. This blood supply is delivered to the brain by the 2 large carotid arteries in the front of your neck and by 2 smaller vertebral arteries at the back of your neck. The right and left vertebral arteries come together at the base of the brain to form what is called the basilar artery. A stroke most often occurs when the carotid arteries become blocked and the brain does not get enough oxygen.
Carotid artery disease increases the risk of stroke in 3 ways:
By fatty deposits called plaque severely narrowing the carotid arteries (atherosclerosis).
By a blood clot becoming wedged in a carotid artery narrowed by plaque.
By plaque breaking off from the carotid arteries and blocking a smaller artery in the brain (cerebral artery).
What is carotid artery angioplasty?
Interventional cardiologists, radiologists or vascular surgeons perform carotid artery angioplasty to open the clogged arteries in your neck to prevent or treat stroke. They use a long, thin tube called a catheter that has a small balloon on its tip. They inflate the balloon at the blockage site in the carotid artery to flatten or compress the plaque against the artery wall.
Carotid angioplasty is often combined with the placement of a small, metal, mesh-like device called a stent. When a stent is placed inside of a carotid artery, it acts as a support or scaffold, keeping the artery open. By keeping the carotid artery open, the stent helps to improve blood flow to the brain. Carotid angioplasty and stenting are usually performed in patients either because they are not candidates for the traditional surgery (carotid endarterectomy) or because the procedure is felt to be less risky than the traditional surgery.
What can I expect during a carotid angioplasty or stent procedure?
The procedure is performed in the cardiac catheterization angiography suite (also called the cath lab). You may be told not to eat or drink anything after midnight the night before the procedure, except for taking certain medicines. If you have diabetes, you should talk to your doctor about your food and insulin intake, because not eating can affect your blood sugar levels.
Talk to your doctor about any medicines that you are taking because he or she may want you to stop taking them or change the dosage before the procedure. This is especially important if you are taking blood-thinning medicines or antiplatelet medicines. It may be helpful to make a list of your medicines and bring it with you to the procedure, so that the doctors know exactly what you are taking and how much.
Once you are in the cath lab, you will see television monitors, heart monitors, and blood pressure machines. You will lie on an examination table, which is usually near an x-ray camera. Small metal disks called electrodes will be placed on your chest. These electrodes have wires called leads, which hook up to an electrocardiogram machine. This machine will monitor your heart rhythm during the procedure. You will rest your head in a cup-shaped area on the examination table, which will help you keep your head still while pictures of your carotid artery are taken. To prevent infection, you will be shaved and cleansed around the area where the catheter will be inserted.
A very small needle will be put in the vein of your forearm. This is called an intravenous line or IV. You will be given an anesthetic medicine to numb the area around where the catheter will be inserted. This needle may hurt a bit, much like at the dentist's after being given Novocain. You should not feel pain during any part of the procedure.
After gaining entrance into the large artery of either your leg or arm, doctors will gently thread the catheter through that artery in your leg or arm and into the carotid artery itself. They use a video monitor (like a TV screen) to see the process. You will not feel the catheter passing through the arteries because the insides of arteries do not have nerve endings. Once the catheter reaches the blocked artery, a harmless dye (called contrast material) is injected, and the doctor will take a picture of the carotid artery. The dye may cause a warm feeling on one side of your face. Contrast material provides a detailed view of the narrowed artery and blood flow to the brain.
A filter that is shaped like an umbrella is then placed beyond the narrowed artery over a tiny wire to catch any plaque that may break away from inside the artery during the procedure. This filter device is called an embolic protection device (EPD) and is needed during most carotid artery procedures.
Once doctors know the exact location of the blockage in the carotid artery, the balloon-tipped catheter is slipped over this wire and advanced to the blockage. When this catheter reaches the blockage, the balloon is inflated. As the balloon expands, it presses against the plaque, compressing it against the artery wall. The balloon is then deflated. Doctors may inflate and deflate the balloon a number of times. A very small, flexible stent is then passed over the area of narrowing and is left inside the carotid artery. A new balloon is placed over the same wire and inflated inside the stent to open it up. The deflated balloon and EPD are removed, leaving the stent behind to hold the artery open.
Firm pressure will be applied to the site where the catheter was inserted to stop any bleeding. You will also be bandaged. To avoid bleeding at the catheter insertion site, you will need to lie very still for several hours, either in the recovery area or in your hospital room.
The procedure usually takes about 30 to 90 minutes. Most patients will spend the night in the hospital for observation. Nurses will watch you during the night to observe your heart rate and blood pressure.
What happens after the procedure?
After you leave the hospital, your doctor will give you specific instructions about drinking plenty of fluids, driving, and bathing. You should avoid standing or walking for long periods for at least 2 days after the procedure.
If you had angioplasty with or without stent placement, you will need to take aspirin and a blood-thinning medicine for a certain amount of time. Your doctor will tell you how and when to take these medicines.
See also on this site:
"A Milestone in Improved Stroke-Prevention Procedure: Carotid Artery Stenting a viable option for patients ineligible for traditional surgery" - news release from THI, May 2010.
See on other sites:
Carotid Artery Surgery
Angioplasty and stent placement-carotid artery-discharge