Carotid artery disease is also called carotid artery stenosis (narrowing). This narrowing is usually caused by the buildup of fatty substances and cholesterol deposits, called plaque. Carotid artery occlusion refers to complete blockage of the artery. When the carotid arteries are obstructed, you are at an increased risk for a stroke, the third leading cause of death in the U.S.
Arteries and Stroke
The carotid arteries are two large blood vessels that supply oxygenated blood to the large, front part of the brain. This is where thinking, speech, personality, and sensory and motor functions reside.
A stroke — sometimes called a “brain attack” — is similar to a heart attack. It occurs when blood flow is cut off from part of the brain. If the lack of blood flow lasts for more than 3 to 6 hours, the damage is usually permanent.
A stroke can occur if:
- The carotid artery becomes extremely narrowed
- There’s a rupture in an artery to the brain that has atherosclerosis
- A piece of plaque breaks off and travels to the smaller arteries of the brain
- A blood clot forms and obstructs a blood vessel
Strokes can occur as a result of other conditions besides carotid artery disease. For example, sudden bleeding in the brain, called intracerebral hemorrhage, can cause a stroke.
The risk factors for carotid artery disease are similar to those for other types of heart disease. They include:
- Increased age
- Hypertension (high blood pressure)
- Abnormal lipids or high cholesterol
- Diet high in saturated fats
- Sedentary lifestyle
- Family history of atherosclerosis, either coronary artery disease or carotid artery disease
You may not have any symptoms of carotid artery disease. Plaque builds up in the carotid arteries over time with no warning signs until you have a transient ischemic attack (TIA) or a stroke.
Signs of a stroke may include:
- Sudden loss of vision, blurred vision, or difficulty in seeing out of one or both eyes
- Weakness, tingling, or numbness on one side of the face, one side of the body, or in one arm or leg
- Sudden difficulty in walking, loss of balance, lack of coordination
- Sudden dizziness and/or confusion
- Difficulty speaking (called aphasia)
- Sudden severe headache
- Problems with memory
- Difficulty swallowing (called dysphagia)
A TIA occurs when there is a low flow of blood or a clot briefly blocks an artery that supplies blood to the brain. With a TIA, you may have the same above symptoms as you would have for a stroke. But the symptoms only last a few minutes or few hours and then resolve.
Diagnostic Testing for Carotid Disease
There are often no symptoms of carotid artery disease until you have a TIA or stroke. That’s why it’s important to see your doctor regularly for physical examinations.
-Physical Examination: Your doctor may listen to the arteries in your neck with a stethoscope. If an abnormal sound, called a bruit, is heard over an artery or vascular channel, it may reflect turbulent blood flow. That could indicate carotid artery disease.
-Carotid ultrasound (standard or Doppler): This noninvasive, painless screening test uses high-frequency sound waves to view the carotid arteries. It looks for plaques and blood clots and determines whether the arteries are narrowed or blocked. A Doppler ultrasound shows the movement of blood through the blood vessels. Ultrasound imaging does not use ionizing radiation (X-rays).
-Magnetic resonance angiography (MRA): This newer imaging technique uses radio waves and a powerful magnet to gather accurate information about the brain and arteries. Then a computer uses this information to generate high-resolution images. An MRA can often detect even small strokes in the brain.
-Computerized tomography angiography (CTA): More detailed than an X-ray, a CT uses X-rays and computer technology to produce cross sectional images of the carotid arteries. Images of the brain can be collected as well. With this imaging test, the scan may reveal areas of damage on the brain. The CT scan uses a low level of radiation.
-Cerebral angiography (carotid angiogram): This procedure is considered the gold standard for imaging the carotid arteries. It is an invasive procedure that lets a doctor see blood flow through the carotid arteries in real time. Cerebral angiography allows the doctor to see narrowing or blockages on a live X-ray screen as contrast dye is injected in the carotid arteries. The procedure provides the best information. It does carry a small risk of serious complication.
Medical Management of Carotid Artery Disease
To effectively treat carotid artery disease, doctors recommend the following medical management:
-Following recommended lifestyle habits
-Taking medications as prescribed
-Considering a procedure to improve blood flow, if your doctor believes it could help
-Control high blood pressure (optimal blood pressure is 120/80 mmHg)
-Have regular check-ups with your doctor
-Have your doctor check your cholesterol and get treatment, if necessary
-Eat foods low in saturated fats, trans fats, cholesterol, and salt
-Eat only enough calories to maintain a healthy weight; avoid weight gain
-Increase exercise to at least 30 minutes of physical activity most days of the week
-Limit alcohol to one drink per day for women, two for men
Your doctor may recommend antiplatelet medications such as aspirin and clopidogrel (Plavix) to decrease the risk of stroke due to blood clots. Your doctor may also prescribe medications to lower cholesterol and/or antihypertensives to lower your blood pressure. In some cases, Coumadin (warfarin), a blood thinner, may be prescribed.
Surgical Treatment of 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 a carotid endarterectomy.
Carotid endarterectomy (CEA) 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.
On your office visit, all of the options available for the treatment of carotid artery disease will be discused in detail for your particular condition.