Interventional Radiology

Carotid Artery Stenting

Carotid artery stenting is a new minimally invasive treatment that has been approved by the FDA (Food and Drug Administration) for the prevention of stroke for patients who are of high-risk for the conventional surgical option, called carotid endarterectomy (CAE). The therapy is currently being evaluated by RANK doctors as part of a multi-center clinical trial to determine the effectiveness and safety of the treatment in expanded patient populations.

In this procedure, an interventional radiologist uses a combination of balloon angioplasty and a stent to unblock and reopen the carotid artery.

Your physician might decide that carotid stenting is a better option for you because you would not need to have anincision in your neck or general anesthesia necessary for CAE. Keep in mind that carotid stenting does not have the long history that CAE has, although clinical studies have shown that carotid stenting is as safe and effective as CAE.

How Should I Prepare For The Procedure?

In the days prior to your treatment, make sure you:

  • Take all of your prescription medications. Tell your doctor if you are taking any other medication.
  • Tell your doctor about any allergies you have, especially to contrast dye or iodine, or to materials such as metals (nickel-titanium or stainless steel) or plastics (polyurethane).
  • Tell your doctor if you cannot take aspirin, since aspirin and other medications are usually begun prior to a procedure and continued for several months thereafter.
  • Do not eat or drink anything after midnight on the night before your procedure.
  • Follow all instructions given to you by your doctor or your nurse.

Before Your Procedure

  • Your doctor will explain the possible risks and benefits of the stenting procedure and answer any questions you or your family may have.
  • You may be given a sedative before the procedure to relax you. The sedative may also make you sleepy.

What Does The Equipment Look Like?

Carotid artery angioplasty and stent placement are monitored as they take place using high-resolution angiography equipment.

The equipment includes a balloon catheter, a small, thin angioplasty catheter with a balloon at its tip, and a wire mesh stent that is collapsed when passed into the artery. Stents come in varying sizes so that in each case it matches the size of the diseased artery. Carotid artery stenting also uses an embolic protection device, or filter, to trap dislodged pieces of plaque that may come loose during the angioplasty and stenting procedures.

How Does The Procedure Work?

Stent
Stents are used to hold open areas of arteries narrowed by artherosclerosis

The procedure uses a stent (small latticed metal tube) to open partially blocked arteries and to hold the plaque against the artery wall. The stent is made from nickel-titanium, a metal that is bendable but springs back into its original shape after being bent. An embolic protection device is also used to help catch any pieces of plaque or other particles that may be released during the procedure. The stent is introduced into the narrowed blood vessel on a catheter, after an embolic protection device has been placed beyond the narrowed area of the artery. The interventional radiologist maneuvers the stent on a catheter into the vessel, and positions the stent across the narrowed area in your carotid artery. The stent is released and stays in place permanently, holding the artery open and improving blood flow. The stent also holds the plaque against the artery wall. This reduces the risk of plaque breaking off, traveling into your brain, and causing a stroke. All of the devices, except the stent, are taken out your body at the end of the procedure.

How Is The Procedure Performed?

Click to view an animation of the procedure

During the procedure, a catheter is inserted through a tiny incision in the groin into the femoral artery, a large blood vessel in the leg. Using fluoroscopy or x-ray, the catheter is navigated through the patient’s blood vessels to the site of the blockage. An embolic protection system with a filter that catches any loose pieces of plaque is first delivered to the artery and opened against the artery walls. A balloon catheter is next delivered to the site and then expanded to press plaque against the artery walls, where another catheter is used to deliver a stent to the blockage site. The stent is placed to help keep the vessel open.

Plaque that is dislodged during the procedure is captured by the embolic protection system, which is then collapsed and removed.

What Will I Experience During The Procedure?

When you receive a sedative through the IV line at the outset, you will feel relaxed and sleepy but probably will stay awake throughout the procedure. There should be no pain when the catheter first is inserted into the groin artery, but you may notice slight pressure. You may feel pain briefly in the part of your body closest to the site of angioplasty when the balloon is inflated. You will have to remain flat on your back and avoid moving your leg or groin for about six hours. Most patients will be able to walk about 6 to 8 hours after angioplasty. Most patients return home the same day, but some stay in the hospital for a short time.

On returning home you should take it easy, avoid driving for 24 hours, and drink plenty of fluids. You should avoid strenuous exercise for at least two days. It is best not to take a hot bath or shower for the first 12 hours, and to avoid smoking for 24 hours or longer. If bleeding begins where the catheter was inserted, you should lie down, apply pressure to the site, and have someone call your doctor right away. Any change in color or a warm feeling in this area are also signs that something is wrong, as is pain in the area where the balloon was inflated.

In stent placement cases, you will be asked to take aspirin or another anti-platelet drug indefinitely. MR imaging should be avoided for a month unless a radiologist approves the study. Metal detectors will not affect the stent.

Who Interprets The Results And How Do I Get Them?

The radiologist judges the technical results of angioplasty and stent placement by comparing the pre- and post-procedure angiograms. If any narrowing remains, it should not exceed 30 percent of the normal vessel diameter. The patient can be told of the technical result as soon as the procedure is completed, though it is best to wait until the sedative has worn off. The clinical outcome may take longer to gauge.

What Are The Benefits Vs. Risks?

Benefits

  • Angioplasty and stenting are much less invasive than open CAE surgery. When angioplasty succeeds, major surgery and use of a heart-lung machine are avoided. Overall cost is much less, and the hospital stay is days rather than weeks.
  • Angioplasty and stent placement can be done using only local anesthesia; you will not require a general anesthetic. No surgical incision is needed—only a small nick in the skin that does not have to be stitched closed. You can return to your normal activities shortly after the procedure.
  • Carotid artery stenting with distal embolic protection restores the flow of oxygen and nutrients to the brain while managing the risk of plaque breaking off, traveling into your brain, and causing a stroke.

Risks

  • The risk of serious effects from angioplasty or stent placement is substantially lower than open surgical procedures. There is a rare risk of vessel rupture, which could require surgery or be life threatening.
  • You may have an allergic reaction to the contrast material injected for angiography. The risk of this happening is greater in patients with kidney disease, diabetes or asthma and those who have had a previous reaction to x-ray contrast material.
  • Heavy bleeding from the catheter insertion site may call for special medication or blood transfusion.
  • There is a risk of stroke when angioplasty is performed on the carotid artery and a stent is placed. This is because a blood clot may form and travel to small brain vessels, where it stops blood flow to brain tissue that requires a steady oxygen supply.

What Are The Limitations Of Carotid Artery Stenting?

Although stents have been widely used in other vessels in the body, it is relatively new to put them into the carotid arteries. The possible benefit of choosing this treatment has been demonstrated to the FDA (Food and Drug Administration) through rigorous clinical trials involving patients having carotid artery disease.

Your doctor should not choose carotid artery stenting for you if:

  • The narrowed area in your carotid artery is located beyond sharply curved vessels, making it difficult to place the stent and embolic protection device
  • You can’t take anticoagulants (medicines that make your blood take longer to form a clot)
  • You can’t take antiplatelets (medicines that make it harder for cells in your blood to form a blood clot)
  • You are allergic to nickel-titanium, the metal used in the carotid stent

 

To get more information or to schedule a procedure, please call Vascular & Interventional Associates 859-341-4VIA (4842).