Carotid Artery Disease
Carotid artery disease occurs when fatty deposits called plaques clog your carotid arteries. Your carotid arteries are a pair of blood vessels that deliver blood to your brain and head. The buildup of plaques in these arteries blocks the blood supply to your brain and increases your risk of stroke.
Because carotid artery disease develops slowly and often goes unnoticed, the first outward clue that you have the condition may be a stroke or a transient ischemic attack (TIA).
Carotid artery disease is treated by medical therapy, by surgery, or by a combination depending on your individual situation.
Diagnosing Carotid Artery Stenosis
Dr. Rosenkilde is highly skilled at diagnosing carotid artery stenosis in patients referred for evaluation of a bruit (the sound of blood flowing through a narrowing in the artery - this noise can be heard through a stethoscope placed on the neck), temporary loss of vision, memory changes, new-onset slurred speech, TIA and other signs of decreased blood flow to the brain. Sound waves reflected from the structures in the neck can show a narrowed artery.
This test is painless, noninvasive, involves no radiation and is an excellent procedure for screening. He has a state-of-the-art ultrasound specific for this purpose in his Mt Kisco office. Invasive tests that can also be used to diagnose carotid artery stenosis include CT angiography and MR angiogram.
Treatment of symptomatic carotid stenosis:
Surgery better than Stenting?
In recommending treatment for a patient, the physician considers these factors:
- Whether or not the patient has symptoms
- Whether or not medical therapy has been tried and is working
- How much narrowing (stenosis) is present according to ultrasound or angiogram tests
Studies show that a surgical procedure called carotid endarterectomy is more effective than medical treatment in patients who meet any of the following conditions:
- The patient is symptomatic and has greater than 70% stenosis
- The patient has no symptoms and has greater than 80% stenosis based on ultrasound or 60% by angiography
- The patient has moderate-grade carotid artery stenosis which is continuing to cause symptoms even with medical management.
In patients who have symptoms and greater than 70% stenosis, the results of a large number of prospective randomized trials show that treatment with a combination of carotid endarterectomy and aspirin results in dramatically lower rates of stroke than treatment with aspirin alone.
For this reason, surgical treatment is recommended for symptomatic patients who have a greater than 70% stenosis as well as for symptomatic patients who have greater than 50% stenosis and are continuing to have symptoms despite being on medial therapy.
Studies also show that asymptomatic patients benefit from surgical treatment compared to medical treatment if the operation is performed by a surgeon who has a personal record of very low morbidity and mortality rates for this operation.
Most patients who have asymptomatic carotid stenosis will not go on to have a stroke. However, more than 50% of patients who go on to have a stroke will have proceeded from being asymptomatic one day to having a stroke the next.
Who Is Likely to Have a Stroke?
The challenge is to identify which patients who have asymptomatic stenosis will develop a stroke and which patients will remain asymptomatic. For this reason, Dr. Rosenkilde and many of his colleagues believe that surgical therapy should be considered for an asymptomatic patient if the patient is a good risk and the surgeon’s morbidity and mortality results are acceptable.
When discussing treatment options with a patient, the neurosurgeon should inform the patient of his or her own morbidity and mortality rates for the procedures that are being considered.
Clinical trials of carotid stenting are ongoing. It appears to be an acceptable alternative for selected high-risk patients who meet certain criteria.
Surgery for the prevention of stroke has a long record of efficacy in selected patients. Identifying those patients who will benefit from surgery for carotid artery disease can go a long way toward reducing the number of people who suffer morbidity or mortality from stroke.
Individual patients can help reduce their risk of stroke by controlling hypertension, recognizing the symptoms of carotid artery disease, and seeking medical care when symptoms occur.
Treatment of carotid artery disease usually involves a combination of lifestyle changes, medications and, in some cases, surgery or a stenting procedure. In its early stages, carotid artery disease often doesn't produce any signs or symptoms. You and your doctor may not know you have carotid artery disease until it's serious enough to deprive your brain of blood.
If that happens, you may develop signs and symptoms of a stroke or TIA — an early warning sign of a future stroke.
As in a previous entry on this site, signs and symptoms of TIA may include:
- Sudden numbness or weakness involving your face, arm or leg, on one side of your body
- Slurred or garbled speech or difficulty understanding others
- Sudden blindness in one eye
Even if the signs and symptoms last only a short while — usually less than an hour but, technically, anything less than 24 hours — and then you feel normal, tell your PCP right away.
Talk to your PCP if you have risk factors for carotid artery disease. Your doctor may recommend some tests to see what condition your arteries are in.
Even if you don't have any signs or symptoms, Dr. Rosenkilde may recommend aggressive management of your risk factors to protect you from stroke.
Seeing a neurologist early increases your chances that carotid artery disease will be detected and treated before a disabling stroke occurs. Make sure your close friends and family know the signs and symptoms of stroke and understand that it's critical to act fast in the event of a possible stroke.
Normal, healthy carotid arteries — like any other healthy artery — are smooth and flexible and provide a clear pathway for blood flow. If you place a finger under your jawbone, on either side of your Adam's apple, you're likely to feel your carotid artery pulse.
Your carotid arteries carry oxygen- and nutrient-rich blood to your cerebral cortex and other vital brain structures, which are responsible for your day-to-day functioning. Over time and, normally, with advancing age, the carotid arteries can become stiff and narrow due to a gradual accumulation of plaques, a process called atherosclerosis. Plaques consist of clumps of cholesterol, calcium, fibrous tissue and other cellular debris that gather at microscopic injury sites within the artery.
When a lot of these plaques accumulate, narrowing the carotid artery and substantially restricting blood flow, doctors label this as carotid artery disease.
Factors That Stress Your Arteries
Risk factors for injury, buildup of plaques, and disease include the following:
Aging. With age, your arteries become less elastic and more prone to injury.
High blood pressure. High blood pressure is an important risk factor for carotid artery disease. Excess pressure on the walls of your arteries can weaken them and leave them more vulnerable to damage.
Smoking. Nicotine can irritate the inner lining of your arteries. It also increases your heart rate and blood pressure.
Abnormal blood-fat levels. High levels of low-density lipoprotein (LDL) cholesterol, the "bad" cholesterol, and high levels of triglycerides, a blood fat, encourage the accumulation of plaques.
Diabetes. Diabetes affects not only your ability to handle glucose appropriately, but also your ability to process fats efficiently, placing you at greater risk of high blood pressure and atherosclerosis.
Obesity. Carrying excess pounds increases your chances of high blood pressure, atherosclerosis and diabetes.
Heredity. Having a family history of atherosclerosis or coronary artery disease increases your risk of developing these conditions, as well.
Physical inactivity. Lack of exercise contributes to a number of conditions, including high blood pressure, diabetes and obesity.Often, these risk factors occur together, creating even greater risk than if they occur alone.
Aggressive Therapy of Carotid Stenosis
There is evidence that the periprocedural rate of stroke or death may be greater with carotid artery stenting than with carotid endarterectomy in patients with symptomatic carotid disease.
In a recent meta-analysis of the three largest randomized trials (ICSS, EVA-3S, and SPACE) with 3433 patients, the proportion with stroke or death at 120 days after randomization was significantly higher for the stenting group compared with the endarterectomy group.
Furthermore, the estimated risk of stroke or death for patients age 70 and older was approximately two-fold higher for the carotid stenting group compared with the endarterectomy group.
•Symptomatic carotid disease is defined as focal neurologic symptoms that are sudden in onset and referable to the carotid artery distribution within the previous four to six months. These symptoms may be transient ischemic attacks, episodes of transient monocular blindness, or minor (nondisabling) ischemic strokes.
•Treatment options for symptomatic carotid atherosclerotic disease include carotid endarterectomy (CEA), carotid artery stenting (CAS), and medical management. All recommendations regarding revascularization with CEA or CAS are made with the provision that that the perioperative risk of stroke and death is less than 6%.
•For patients with recently symptomatic carotid stenosis of 70 to 99 % who have a life expectancy of at least five years, CEA rather than CAS may be preferable when the following conditions apply:
- A surgically accessible carotid lesion
- Absence of clinically significant cardiac, pulmonary, or other disease that would greatly increase the risk of anesthesia and surgery
- No prior ipsilateral endarterectomy
- For patients older that 70 years of age with symptomatic carotid disease, the perioperative risk of stroke or death is higher with stenting than with CEA.
Stenting Recommended for Specific Patients
For select patients with recently symptomatic carotid stenosis of 70 to 99 %, CAS (stenting) rather than CEA (surgery) is likely favored if any of the following conditions are present:
- A carotid lesion not surgically accessible
- Radiation-induced stenosis
- Restenosis after endarterectomy
- Clinically significant cardiac, pulmonary or other disease that greatly increases the risk of anesthesia and surgery
[edited from mayoclinic.com and webmd.com]
Andreas Vesalius, De Humani Corporis Fabrica, 1543
