Carotid Artery Disease
Carotid artery disease occurs when fatty deposits, called plaques, clog carotid arteries. The carotid arteries are a pair of blood vessels that deliver blood to the brain. Carotid artery stenosis is the narrowing or constriction of the carotid artery. It is possible to have stenosis of both carotid arteries. The buildup of plaques in these arteries blocks the blood supply to the brain and increases risk of stroke.
Because carotid artery disease develops slowly and often goes unnoticed, the first outward clue about the condition may be a stroke or transient ischemic attack (TIA), also called a ministroke.
Treatment of carotid artery disease usually involves a combination of lifestyle changes, medications and, in some cases, surgery or a stenting procedure.
Carotid artery disease is caused by a gradual build up of an atherosclerotic plaque, a process called atherosclerosis, that can cause the carotid arteries to become narrow and stiff and this can impair blood flow to the brain.
Risk factors are habits that increase chances of developing carotid artery disease. Some risk factors a person can change—modifiable risk factors—and others a person cannot change—non-modifiable risk factors.
Modifiable risk factors include:
- Tobacco use
- High blood pressure
- High cholesterol and triglyceride levels
- Diabetes mellitus
- Exposure to second-hand smoke
- Obesity not exercising regularly and unhealthy eating habits/diet
Non-modifiable risk factors include:
- Sex (male)
- Family history
- Genetic conditions
- Exposure to radiation for head, neck or chest cancers
The biggest complication related to carotid artery disease is a stroke. The most common ways a stroke can occur in this instance are via reduced blood flow (hemodynamic) resulting in a decrease of blood going to the brain and potentially progressing to carotid artery thrombosis (total occlusion). Another possibility is that the atherosclerotic plaque ruptures and small pieces block blood vessels downstream in the brain (embolus). This cuts off blood supply to that particular area of the brain resulting in a stroke.
Warning signs of stroke and TIA include:
- Numbness, weakness or loss of feeling of face, arm, or leg (usually on one side of the body)
- Difficulty speaking, getting words out, or understanding others
- Change in vision, particularly a “shade or film” coming down over one eye
- Double vision
- Dizziness, loss of balance or coordination
- Difficulty swallowing, coughing with eating or swallowing
Carotid artery disease may not always come with symptoms. A healthcare provider may diagnose the disease by listening to arteries with a stethoscope. They may also obtain information by asking questions about a patient’s family medical history, performing a physical exam and ordering further tests. Some of these tests may include:
- Carotid ultrasound: This is a non-invasive test where a probe is placed on the neck over the artery to evaluate how fast blood is traveling through the vessel. This can help to determine how narrow an artery may be.
- CTA Neck: For this, a contrast dye is injected into an IV in the arm or hand to take images of the blood vessels of the neck and sometimes the head.
- MRA: This is another blood vessel study that can show blood vessel changes, such as blockage or narrowing, through the injection of IV gadolinium, a non-iodine-based dye injection.
- Arteriogram or Digital Subtraction Angiography (DSA): For this, a catheter is placed into the artery—most often the femoral artery. Then, IV dye is injected and X-rays are taken to evaluate those neck and head blood vessels.
The goal in treatment of carotid artery disease is to prevent strokes. Treatment options depend on the severity of narrowing of the blood vessels. Treatment options can include lifestyle changes, medications, surgery, and interventional procedures. Often times a combination of these is used in the management of carotid artery disease.
- Lifestyle Changes: These are changes that a patient can make to improve your risk factors for this disease. They include eating a healthy diet, quitting smoking, exercising regularly, controlling blood pressure and maintaining normal blood sugars.
- Medications: The use of anti-platelet medications is often prescribed in the management of carotid artery disease. These help to prevent the formation of blood clots—examples include aspirin, clopidogrel/plavix or aggrenox. Additionally, medications to control blood pressure may also be prescribed. Finally, a statin drug may be recommended for improved control of cholesterol levals and to help prevent or delay further progression of atherosclerotic plaques.
- Procedures: There are a couple of options to intervene and repair narrowed blood vessels. A blood vessel will likely be recommended for repair if a patient has significant carotid artery disease, identified as a high grade stenosis via imaging studies and/or a patient is symptomatic and has experienced a previous TIA or stroke event. There are two primary procedures:
- Carotid Endarterectomy: This surgery will most likely be offered if a patient meets certain criteria, including having no history of cardiac conditions, no history of radiation to the neck and no contralateral carotid artery occlusion. The surgery removes the plaque buildup with an incision that is made along the front of the neck, opening the artery and removing the buildup. Most patients require one or two nights in the hospital post surgery for recovery.
- Carotid Angioplasty and Stenting: This procedure involves a patient undergoing an angiogram—where a catheter is placed at the level of stenosis and a tiny balloon is pushed into the narrowed area and inflated, pushing the plaque buildup to one side and widening the artery opening. The procedure is done with small filter in place to protect the brain against any plaque debris. Sometimes the balloon must be inflated multiple times. It is possible an expandable mesh tube, called a stent, will be placed across the area of stenosis to help keep the artery open. The small filter is removed after the stent is in place. The use of a stent will make it likely for a patient to need to use dual antiplatelet medications (i.e. aspirin/clopidogrel(Plavix)) for a period of 6-12 months, or longer. Most patients require a one-night hospital stay for this procedure.