About carotid artery disease
What is carotid artery disease?
The carotid arteries provide blood supply to the head. There are two common carotid arteries, located on each side of the neck, that divide into the internal and external carotid arteries. The external carotid artery provides blood supply to the scalp, face, and neck while the internal carotid artery supplies blood to the brain.
Narrowing of the internal carotid artery may decrease blood supply to half of the brain that it supplies. This narrowing called atherosclerosis (atheroma = lump of plaque + sclerosis = hardening) occurs because of the accumulation of plaque on the inside of the artery wall. Plaque begins as a soft, waxy collection of cholesterol and triglycerides but over time begins to harden and calcify. Often it occurs where increased blood pressure and blood turbulence irritates the inner lining of the artery and this often occurs where the internal and external carotid arteries split (bifurcation).
As the carotid artery begins to further narrow, the pressure within the artery continues to increase. This may cause the plaque to rupture, causing blood clots to form. A large clot may completely block (occlude) the artery or smaller clots and bits of plaque may travel into smaller arteries within the brain and cause disruption of blood supply to parts of brain tissue.
It is only when a stroke or transient ischemic attack occurs, or a bruit (blowing or whistling sound) is found on physical examination by your doctor, that the diagnosis of carotid artery disease is usually made. Otherwise, the narrowing carotid artery does not cause symptoms.
What are the symptoms for carotid artery disease?
In its early stages, carotid artery disease often doesn't produce any signs or symptoms. The condition may go unnoticed until it's serious enough to deprive your brain of blood, causing a stroke or TIA.
Signs and symptoms of a stroke or TIA include:
- Sudden numbness or weakness in the face or limbs, often on only one side of the body
- Sudden trouble speaking and understanding
- Sudden trouble seeing in one or both eyes
- Sudden dizziness or loss of balance
- Sudden, severe headache with no known cause
When to see a doctor
Seek emergency care if you experience any signs or symptoms of stroke. Even if they last only a short while and then you feel normal, see a doctor right away. You may have experienced a TIA, an important sign that you're at risk of a full-blown stroke.
Talk to your doctor if you have risk factors for carotid artery disease. Even if you don't have any signs or symptoms, your doctor may recommend aggressive management of your risk factors to protect you from stroke. Seeing a doctor early increases your chances that carotid artery disease will be found and treated before a disabling stroke occurs.
What are the causes for carotid artery disease?
Carotid artery disease is caused by a buildup of plaques in arteries that deliver blood to your brain. Plaques are clumps of cholesterol, calcium, fibrous tissue and other cellular debris that gather at microscopic injury sites within the artery. This process is called atherosclerosis.
Carotid arteries that are clogged with plaques are stiff and narrow. Clogged carotid arteries have trouble delivering oxygen and nutrients to vital brain structures that are responsible for your day-to-day functioning.
What are the treatments for carotid artery disease?
The treatment for carotid artery disease needs to be individualized for each patient and situation. Discuss your options with your doctor. Possible treatments include:
If the carotid artery is less than 50% narrowed, medical treatment is recommended. This includes stepwise antiplatelet therapy. Platelets are blood cells that help clot blood and in patients who have had symptomatic carotid artery disease, meaning that they have experienced a TIA, and decreasing platelet stickiness may be helpful in minimizing future stroke events. The first line medication is to treat the disease is aspirin. If the patient was already taking an aspirin and still experienced a TIA, the next line medication may be dipyridamole/aspirin combination (Aggrenox) or clopidogrel (Plavix).
What are the risk factors for carotid artery disease?
Factors that increase your risk of carotid artery disease include:
- High blood pressure. Excess pressure on artery walls can weaken them and make them more vulnerable to damage.
- Tobacco use. Nicotine can irritate the inner lining of your arteries. Smoking also increases your heart rate and blood pressure.
- Diabetes. Diabetes lowers your ability to process fats efficiently, placing you at greater risk of high blood pressure and atherosclerosis.
- High blood-fat levels. High levels of low-density lipoprotein cholesterol and high levels of triglycerides, a blood fat, encourage the accumulation of plaques.
- Family history. Your risk of carotid artery disease is higher if a relative has atherosclerosis or coronary artery disease.
- Age. Arteries become less flexible and more prone to injury with age.
- Obesity. Excess weight increases your chances of high blood pressure, atherosclerosis and diabetes.
- Sleep apnea. Spells of stopping breathing at night may increase your risk of stroke.
- Lack of exercise. It contributes to conditions that damage your arteries, including high blood pressure, diabetes and obesity.
Is there a cure/medications for carotid artery disease?
If there is severe narrowing or blockage in the carotid artery, a procedure can be done to open the artery. This will increase blood flow to the brain to prevent future stroke. Your doctor may suggest either of the following procedures:
- Carotid endarterectomy (CEA). This has been the commonly performed procedure for patients who have carotid atherosclerosis and TIAs or mild strokes. While you’re under general anesthesia, an incision is made in the neck at the location of the blockage. The surgeon isolates the artery and surgically removes the plaque and diseased portions of the artery. Then, the artery is sewn back together to allow improved blood flow to the brain. The risks and benefits of CEA depend on your age, the degree of blockage, and whether you’ve had a stroke or TIA.
- Carotid artery stenting (CAS). Carotid artery stenting (CAS) is a newer treatment option. It’s less invasive than carotid endarterectomy and is performed in a catheterization laboratory. With CAS, a small puncture is made in the groin. A specially designed catheter is threaded to the area of narrowing in the carotid artery. Once in place, a small balloon tip is inflated for a few seconds to open the artery. Then, a stent is placed in the artery and expanded to hold the artery open. A stent is a small tube that acts as a scaffold to provide support inside your artery. The stent is usually made of metal and is permanent. It can also be made of a material that the body absorbs over time. Some stents have medicine that helps keep the artery from getting blocked again. CAS is a newer procedure, and there is still some controversy as to how well it prevents strokes caused by carotid artery disease. Research suggests that the standard CEA may be safer than CAS, which may raise the risk of stroke or death post procedure.