Carotid artery disease occurs when the major arteries in your neck narrow or occlude. These arteries are called carotid arteries and are responsible for supplying blood to your brain. The carotid arteries start in the chest and end in the brain tissue inside the skull.
As you age, you are susceptible to developing carotid artery disease. While symptomatic carotid artery disease occurs in only one percent of adults aged 50-59 years, it occurs in ten percent of people aged 80-89 years. The lining of healthy arteries is inherently smooth and flat, and as we age, sticky material called sclerotic plaque forms. The plaques are formed by deposits of cholesterol, foci of calcification, and fibrous tissue. As more plaque forms, the arteries become narrowed and hardened.
This process is known as atherosclerosis or hardening of the arteries. When enough plaque reduces or interferes with blood flow through the carotid arteries, doctors call it carotid artery disease. Since carotid artery disease can lead to stroke, it is a serious set of health problems. Some of the deposited plaque is not so strong and can be easily destroyed, which in turn creates a rough and irregular arterial lining. If these conditions occur, your body will respond in the same way that platelets and clotting cells gather toward a wound after you are injured. A large blood clot may form in your carotid artery or its branches. If the obstruction of this clot slows or completely stops the blood flow to the brain, it can lead to a stroke.
More commonly, a part of the plaque or blood clot breaks off from the plaque and runs with this blood flow. Some particles may become lodged in the small arteries of the brain and occlude them, causing a stroke. Fortunately, you may be able to avoid or slow the development of carotid artery disease. The most important shift in avoiding the formation of this disease is to quit smoking. Other ways to prevent the formation of carotid artery disease are to exercise regularly, eat a healthy diet, and maintain a healthy weight. Controlling triggers of carotid artery disease such as diabetes, high blood pressure, and high cholesterol can also play a preventive role.
Carotid artery disease can have no clinical symptoms in its early stages. Unfortunately, the first symptom can be a stroke. But it can also be the warning signs of something called transient ischemia or transient ischemic attack stroke.TIA symptoms usually last about one minute and include: weakness, numbness or tingling in one half of the body, such as one arm or one leg.
Symptoms such as inability to control random movements of one arm or one leg, or gradual loss of vision in one eye, slurred speech, etc. These symptoms usually disappear temporarily within 24 hours. However, they should not be ignored. The presence of TIA symptoms indicates a high risk of having a stroke soon. Patients should report TIA symptoms to their doctor. If these symptoms persist for several hours or do not disappear within 24 hours, it means that it is already a stroke. What you need to do is to contact your doctor immediately.
What causes carotid artery disease? Atherosclerosis is largely responsible for carotid artery disease, the cause of which is not fully understood. Plaque can form when the lining of the artery is damaged. Factors that damage the arterial wall include smoking, hypercholesterolemia, and hypertension. There are also rarer causes, like carotid aneurysms and myofibrillar dysplasia, that can lead to carotid artery disease. Some other factors that can raise the likelihood of carotid artery disease are diabetes, and a family history of atherosclerosis.
What kind of tests do we need to do to determine if we have carotid artery disease? First your doctor will ask questions about your daily health, medical history, and related symptoms. A physical examination will also be performed. As part of the history and physical exam, your doctor will ask you if you smoke, if you have high blood pressure, and other questions. He will also want to know when your symptoms occurred and how long they lasted. During the physical examination, your doctor will listen to your carotid murmur and take your blood pressure.
After taking a medical history and physical examination, if your doctor suspects you have carotid artery disease, he will perform a carotid ultrasound on you. During this painless test, the technician will place a small ultrasound probe into your neck. The probe emits ultrasound to test your blood cells and vessels to show problems with blood flow and vascular structure. This test will show you how open your carotid arteries are and how fast they are flowing. Carotid ultrasound can detect the cause of most carotid artery disease. Therefore, doctors usually do not go back for other tests. However, if the ultrasound does not provide the doctor with enough information, he will do some of the following tests.
CT scans and CT angiograms: CT scans and CT angiograms will obtain some form of a slice of the brain and an X-ray of the carotid arteries. CT scans can show areas of ischemia in the brain. CT will clearly show the narrowing of the arteries in the neck and brain.
Magnetic Resonance Angiography: MRA uses radio waves and magnetic fields to create detailed images. Some forms of the test can show blood flow dynamics and are useful in the evaluation of carotid artery disease. To improve the accuracy of the test, doctors sometimes inject a substance called “gadolinium” to make the arteries appear more clearly.
Angiography: In this test, the doctor injects a contrast medium through a catheter inserted into the artery and obtains an x-ray. Because X-rays cannot pass through the contrast, the shape of the blood vessels can be shown on the X-ray. This test will show how blood flows through the artery and will show if there are any narrowings. There are some risks associated with angiography, including a very small chance of stroke. This is exactly why doctors do not use it as the test of choice to confirm the diagnosis and follow up. Angiography is also used in vascular surgery for carotid angioplasty and stenting, which will be discussed later.
How should carotid artery disease be treated?
Treatment is determined by your condition, regardless of whether you have symptoms of carotid artery disease or your daily health status. If you have another condition, you must make sure you follow your doctor’s orders to deal with it. For example, if you have diabetes, make sure you monitor and control your blood sugar. If you have high blood pressure, your doctor will prescribe antihypertensive medication for you. If you are still smoking, quit it. Your doctor will check your blood cholesterol levels to make sure they are within normal limits. Statin drugs may also be prescribed to lower your blood lipids.
Surgical procedures
When your carotid artery disease is severe or has progressed, you will need surgical treatment. Signs of severe disease include a cluster of TIA symptoms, a history of stroke, or asymptomatic carotid artery stenosis. During surgery, a vascular surgeon will remove the plaque that is blocking the carotid artery. This procedure is called a carotid endarterectomy. Depending on the circumstances, local or general anesthesia may be used.
After the anesthesia has taken effect, the surgeon will make an incision in the patient’s neck and remove the plaque from the carotid artery lining. This procedure will remove the plaque, leaving the artery smooth and open. You can be discharged from the hospital as soon as you feel well, even after the surgery. Under the right circumstances, if it is a high quality vascular surgery, it will be safe and effective in the long term.
Angioplasty and Stenting
An emerging minimally invasive procedure used to treat carotid artery disease – angioplasty and stenting. Angioplasty and stenting is usually performed using local anesthesia. To perform the procedure, the vascular surgeon will insert a long, thin catheter through a small puncture in the inguinal artery and through the vessel to the carotid artery. The surgeon will then inject a contrast medium into the vessel and perform an angiogram. This is done to show the location and specifics of the plaque blocking the carotid artery.
The surgeon will then insert another catheter carrying a tiny balloon that can be inflated and deflated to expand the plaque in the artery wall. The surgeon will then place a tiny metal mesh stent to keep the artery open to blood flow. The length of stay after angioplasty and stenting is almost identical to that of an endarterectomy. This procedure is controversial due to the lack of conclusive, long-term outcomes. Nonetheless, angioplasty and stenting may be a good option for those patients with high-risk factors that preclude endarterectomy. This has been recognized by patients who are clinically symptomatic and at high risk for endovascular endoplasty, or who have agreed to participate in ongoing clinical studies to determine its effectiveness.
What can I do to stay healthy?
If you don’t need surgical treatment, make sure you and your nearest family member are aware of the warning signs of TIA. Follow your doctor’s orders and prescribe something like aspirin to thin your blood, or a statin to lower your lipids. It’s also important to come back for regular follow-ups, as carotid blockages can get worse over time or can have no clinical symptoms. Some lifestyle changes in triggers can prevent the progression of carotid artery disease. For smokers, the first step is to stop smoking. Some other changes that can reduce the risk of developing carotid artery disease are weight loss, consistent exercise, and a low-fat diet.