What is carotid stenosis?
The carotid arteries are blood vessels in the neck that carry blood to the brain. The carotid arteries are located on both sides of your neck.
Carotid stenosis is a condition in which these arteries become narrowed or blocked. Stenosis occurs when a sticky, fatty substance (plaque) builds up in the inner lining of the arteries. The plaque may slowly block the artery, or cause a clot to form. These clots can lead to a stroke.
Risk factors for carotid stenosis
Several factors listed below put you at risk for carotid stenosis:
High blood pressure
Heart disease or other vascular history
Symptoms of carotid stenosis
Not all patients with carotid stenosis have symptoms; others have symptoms of a TIA (transient ischemic attack) or stroke. Symptoms may include:
Weakness, tingling, or numbness on one side of your face or one side of your body.
Difficulty with talking; difficulty understanding someone speaking to you
Loss of balance or coordination; difficulty walking
Visual symptoms – sudden loss of vision, blurred vision, or difficulty seeing out of one eye
How is carotid stenosis diagnosed?
A complete physical and neurological exam is needed, although this exam may be normal. Diagnostic tests may include:
Magnetic Resonance Imaging / Angiography (MRI or MRA)
Computerized Tomography Angiography (CTA)
Cerebral / Carotid Angiography
How is carotid stenosis treated?
Treatment options are determined by location of stenosis, degree of stenosis, symptoms, age and medical history of the patient. Imaging and medical history are reviewed prior to scheduling a consultation. This will help determine if further imaging or testing is required.
There are several ways in which carotid stenosis is treated.
This procedure is similar to an angiogram. General anesthesia is required for this procedure. A thin tube (catheter) is placed in the femoral artery (groin area) through a small nick in the skin about the size of a pencil tip. The catheter is guided to the area to be studied. A dye (contrast) is then injected into the catheter while taking x-rays of the area are taken. The contrast makes the stenosis visible on the x-ray.
Once the area of stenosis is identified, a balloon is inflated, opening up the artery. The stent is then deployed, allowing the artery to remain open.
This procedure is performed by an Interventional Neuroradiologist.
Under general anesthesia, an incision is made in the neck at the area of blockage. The area of plaque is surgically removed. The artery is sewn back together, allowing improved blood flow.
This procedure is performed by a Vascular Surgeon.
This treatment often consists of medication therapy. Medications such as aspirin and Plavix (antiplatelet medication) and Coumadin (anticoagulant) interfere with the formation of blood clots. Other medications (antihypertensives or statins) may be considered based on your medical history and other risk factors.
Additional recommendations of conservative treatment include lifestyle changes such as exercise, healthy eating, quitting smoking, and controlling high blood pressure, cholesterol, diabetes and weight.
How do I prepare for a carotid stenting?
Carotid stenting requires a pre-operative history and physical. You should have this scheduled with your primary care physician within 30 days of your scheduled procedure. Blood work will need to be drawn within 14 days of your scheduled procedure. Necessary blood work includes BUN, creatinine, platelets, hemoglobin, potassium, sodium and INR.
You will contacted by telephone to pre-register for your procedure.
Eating: Do not eat or drink anything for 6 hours prior to your procedure. Maintain hydration – drink extra fluids for 2 days prior to your procedure, unless you are on fluid restrictions from your physician.
Medication: Medications can be taken in the morning with a sip of water. Please bring a list of your medications with you to your appointment.
If you are a diabetic and take Glucophage (Metformin) DO NOT take your morning dose. If you take insulin, ask your doctor about modifying your insulin dose for the day of the procedure.
If you are taking blood thinners (Coumadin/Warfarin, Pradaxa/dabigatran, Aggrenox/aspirin/dipyridamole (or similar medications), ask your doctor about stopping these medications at least 5-6 days prior to your procedure. Please let us know if you are taking clopidogrel (Plavix) or prasugrel (Effient).
You will start clopidogrel (Plavix) and aspirin 7 days prior to your procedure.
Allergies: If you are allergic to contrast dye, please let us know. You will need to take the prescription steroid medication methylprednisolone (Medrol) and diphenhydramine (Benadryl) prior to your procedure.
Kidney Function: If you have a history of renal insufficiency (an increased creatinine level or a decreased GFR) please let us know as you may need to be pretreated with Mucomyst (a medicine that helps to protect your kidney function). Ask your primary care physician about withholding potential nephrotoxic medications you may be taking prior to your procedure.
Smoking: No smoking for 72 hours prior to your procedure.
Driving: You will not be allowed to drive for 24-48 hours after your procedure. You will be admitted after your procedure for an overnight stay.
What happens on the day of the carotid stenting?
You will register in the Radiology department 1 ½ hours prior to your procedure time.
You will change your clothes and wear a hospital gown.
A nurse will review your health history, as well as your medications and allergies.
You may need blood drawn, if not completed within 14 days of your procedure.
You will have an IV started in your arm. This will allow us to give you sedation for your carotid stenting procedure.
You will be asked to empty your bladder.
The Nurse Practitioner and Interventional Neuroradiologist will meet with you to discuss risks and benefits, answer any questions you may have, and have you sign a consent form.
You will taken by cart, to the angiogram suite where you will be transferred to an x-ray exam table.
Your heart rate and blood pressure will be monitored. Your groin will be shaved, prepped and draped. The Interventional Neuroradiologist will numb the area with a local anesthetic.
A small nick is made in the skin at the access site. Using x-ray guidance (fluoroscopy) a thin, small tube (catheter) is inserted through the skin into the blood vessel and guided to the area to be examined (neck, head or spine). The contrast is then injected though the catheter – you may feel a warm flush and/or a metallic taste in your mouth. As the contrast flows through the blood vessels, several sets of pictures are taken.
Next, the Interventional Neuroradiologist will pass a guidewire through the catheter at the blockage site. Another catheter with a very small balloon will be placed across the blockage. The balloon will be inflated, gently dilating the wall of your artery. This will open the artery, which restores proper blood flow through the blood vessel. A stent (wire mesh tube) is then placed across the blockage, which will help keep the artery open.
At the end of the procedure, the catheter is removed and pressure is applied to the groin puncture to stop any bleeding. The opening is then covered with a dressing.
You will be transferred back to the recovery area for observation.
While in the recovery area, nurses will periodically check your vital signs and the incision site. You will later be transferred to your room for an overnight stay.
You will be gradually allowed to get up. Lightheadedness and dizziness may occur if you get up too quickly.
You will be allowed to eat. You will be encouraged to drink fluids.
It is important to drink plenty of fluids for the next several weeks. This will help to avoid headaches.
Gradually increase your activity as tolerated.
You should avoid lifting objects heavier than 10 pounds for 5 days
Avoid bending your leg at the hip and straining.
Support your groin site with your hand when you cough, climb stairs or change positions for the first 48 hours following your procedure.
Keep the puncture site dry. If you have bleeding or swelling under the skin, lie down and put firm pressure slightly above the puncture site for 10 to 20 minutes.
You may shower 24 hours after your procedure. Gently wash the site with warm water. Dry gently. If there is still a slit in the skin, cover with a bandage until it closes. You may shower. Do not take tub baths, or swim in lakes or pools until your puncture site is healed completely.
Because of the sedation given to you for your angiogram, you should not do the following for 24 hours after your procedure:
Drive a motor vehicle.
Drink alcoholic beverages.
Make critical decisions or sign important documents.
You will continue the clopidogrel (Plavix) and aspirin for 6 weeks to 6 months. A follow-up carotid ultrasound with clinic visit is recommended one month after your stenting procedure. At that time, a decision on how long you will remain on clopidogrel (Plavix) will be made. **Please call us before stopping your clopidogrel (Plavix) for any reason**
A carotid ultrasound is also recommended 6 months, 12 months and yearly thereafter from your procedure date.