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VASCULAR DISEASE
Carotid Artery Disease
What is Carotid Artery Disease?
The Carotid Arteries connect the heart to the brain. Specifically, the internal carotid artery (see picture at left) is the direct connection to the brain, bringing blood and oxygen to the brain to keep it functioning properly. Atherosclerosis, also called “hardening of the arteries”, can occur in these vessels, causing a blockage of flow to the brain. When this occurs, it increases the risk of future stroke.
Unfortunately, as the blockages are building up, there are no symptoms, and therefore no way of knowing that the patient is at risk. Sometimes, a doctor can hear a sound in the neck, called a bruit, which can prompt further investigation. More often, these blockages are found on screening ultrasound examination. If the blockage is not found soon enough, the first symptom is often either a mini-stroke, called a TIA (Transient Ischemic Attack), or a full blown stroke. Back to top
What are the Risk Factors for Carotid Artery Disease?
The risk factors for carotid artery disease are the same as those for all types of atherosclerosis:
- Smoking
- High Blood Pressure
- Diabetes
- High Cholesterol
- Family history of stroke of heart attack
- Age (>65)
- Prior history of coronary heart disease or peripheral vascular disease (PAD)
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What are the Symptoms of Carotid Artery Disease?
The majority of patients with carotid artery disease have no symptoms. However, there are warning signs of an impending stroke. A TIA, or mini-stroke, is a neurological deficit that lasts less than 24 hours and usually resolves on its own. This can be characterized by:
- Weakness, numbness, or paralysis of your arm, leg, face, or on one side of your body
- Temporary blindness or blurriness in one eye. This symptom, called amarosis fugax, has been described as having a window shade pulled over one eye.
- Slurring of speech, difficulty talking or understanding what others are saying
- Loss of coordination, dizziness, or confusion
- Trouble swallowing
If a person experiences any of these symptoms, he must seek medical attention immediately, as this is a warning sign that a full blown stroke may be imminent. Immediate medical attention can save your life or increase your chance of full recovery.
A CVA (Cerebrovascular Accident) is a full blown stroke, characterized by a neurological deficit that last longer than 24 hours. With prompt medical attention, sometimes the stroke can be reversed, and sometimes full neurological recovery is possible. The presence of carotid artery disease is important to determine, because if present, it can lead to progression of the stroke and further strokes in the future. Back to top
How is Carotid Artery Disease Diagnosed?
 Sometimes a doctor can hear a sound in the neck called a bruit, which can alert him to the presence of disease. The best first test to determine the presence of carotid artery disease is a carotid ultrasound. This is a painless, simple test done in the vascular surgeon’s office that measures the velocity of blood in the internal carotid artery (see picture at right).
A good analogy to how these velocities tell us information is to a garden hose. If you are watering your garden and you want the water to come out faster and go farther, you simply put your thumb over the end of the hose. The more you block the end of the hose, the more forceful the water comes out. Likewise, the higher the degree of blockage in the artery, the faster the blood is moving through it. The ultrasound gives the doctor a rough estimate to the degree of blockage, and if severe he will order further testing.
An ultrasound is not specific enough to base definitive therapy on, but is an excellent screening tool. The definitive test for carotid artery disease is an angiogram. This test can now be done in three different ways: with CT scan, MRI, or traditional angiography, which involves a catheterization through the groin. 
These tests all involve injecting dye into the carotid artery and measuring the exact degree of blockage (see picture at left). After the angiogram, the doctor will determine whether intervention is warranted. Back to top
Do I need treatment?
Carotid artery disease is one of the most well studied diseases in medicine. Over the years, many clinical trials have given doctors good evidence that have led to generally agreed upon recommendations for treatment. The 2 most important pieces of information in determining the need for intervention are the presence or absence of symptoms (TIA or CVA), and the degree of stenosis.
1) Asymptomatic: If patients have no symptoms, such as when the blockage is found on a routine screening ultrasound, the doctor will look for a blockage in the 60% range.
If the blockage is less than 60%, only medical therapy is indicated. This has been shown to be just as good as surgery for preventing future stroke. In addition to the medical therapy, your doctor should also recommend regular ultrasound surveillance to make sure that the blockage does not worsen over time.
If the blockage is greater than 60%, carotid intervention has been shown to decrease the risk of future stroke significantly when compared to medical therapy alone.
2) Symptomatic: If patients have suffered a TIA or a stroke, they are called symptomatic. Again, the degree of blockage that the doctor looks for is 60%.
If the blockage is less than 60%, only medical therapy is indicated. This has been shown to be just as good as surgery for preventing future stroke. In addition to the medical therapy, your doctor should also recommend regular ultrasound surveillance to make sure that the blockage does not worsen over time.
If the blockage is greater than 60%, the risk of future stroke is very high, up to 25% within the ensuing 2 years. In this case carotid intervention has been shown to decrease the risk of future stroke significantly when compared to medical therapy alone.
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How is Carotid Artery Disease Treated?
MEDICAL THERAPY
Medical therapy consists of lifestyle modifications and medicines that “thin” the blood.
Lifestyle Modifications:
- Quit smoking
- Control high blood pressure and diabetes
- Control high cholesterol
- Achieve and maintain a desirable weight
- Regular exercise
Medication:
- Aspirin is the most important medication, and should be taken every day. A baby aspirin is adequate, as no dose of aspirin has been proven to be superior.
- Plavix works in a similar fashion to aspirin, but is more powerful. It is often given in combination with aspirin in patients at especially high risk.
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What is Carotid Intervention?
Carotid intervention is the term used to describe therapies that physically decrease the degree of blockage in the internal carotid artery and improve blood flow to the brain. Historically, a surgery called Carotid Endarterectomy (CEA) was the only such intervention available. More recently, Carotid Artery Stenting (CAS), has been approved for use in a special subset of patients.
Carotid Endarterectomy:
 Carotid Endarterectomy is a surgical procedure. It is done in the operating room under general anesthesia. A small incision is made on the side of the neck, and the internal carotid artery is exposed and clamped. Special maneuvers are performed to ensure that there is adequate blood flow to the brain during this clamping procedure. The artery is then opened, and the blockage is completely removed (see picture at left). After removal, the artery is closed, often with a patch, and blood flow to the brain is restored. This procedure takes about one hour.
Dr. Esposito is a board certified vascular surgeon, and has performed hundreds of successful carotid surgeries. These procedures are performed at Milford Hospital. This procedure is remarkably well tolerated, even by elderly patients with multiple medical problems.  The typical recovery involves an overnight stay in the hospital. There is very little postoperative pain, and the patient is able to eat right away. The patient is typically discharged home after breakfast the day after surgery, often less than 24 hours after being operated upon. The patient can resume normal activities right away. The main risk of the surgery is that a stroke will occur during the procedure, while the artery is clamped. Fortunately, this is a very rare occurrence. After surgery, the patient will continue with lifestyle modifications, aspirin and/or Plavix, and routine ultrasound surveillance of both carotid arteries.
(Picture at right is of a plaque-filled carotid artery.)
Carotid Artery Stenting:
 Carotid Artery Stenting is not a surgical procedure, but rather an endovascular one. This means that it is performed from the inside of the blood vessel, using catheters, balloons, and stents. It is done in a specially equipped X-ray room, and the patient is awake during the procedure. Sometimes a light sedative is given. A blood vessel in the groin is accessed using a catheter, similar to the type used when you get an intravenous line. Using X-ray guidance, a mesh filter is placed above the blockage to prevent any plaque or debris from being dislodged and being sent into the brain. Next, a balloon is gently inflated to push the blockage to the sides of the blood vessel wall (see picture at left). Finally, a flexible metal tube, called a stent (see picture below), is placed in the artery to completely open the artery and restore adequate blood flow to the brain. (See video) After this is completed, the catheter is removed from the groin and sealed with pressure.  There is no surgical incision, only a small pinhole in the groin. The procedure takes between 1 to 2 hours.
Carotid Artery Stenting is a relatively new procedure that has only been approved for use in the United States for a few years. There is no conclusive evidence that it is superior to surgery. In fact, many reports have suggested that it is riskier than surgery. For this reason, surgery is still the procedure of choice for most patients with carotid artery disease. However, in some patients, surgery is very risky. These include patients with severe heart or lung disease, prior neck surgery, and prior neck radiation. For these patients, carotid stenting may be a better option. Because of these reasons, there are strict criteria set up by the federal government that require all doctors and hospitals that offer carotid stenting to go through a vigorous certification process. We are proud that Milford Hospital is one of the few area hospitals certified for this procedure. In addition, Dr. Esposito and Dr. Davis are both certified to perform the procedure, and have performed many of them with excellent results. These procedures are performed at Milford Hospital in a state-of-the-art room that has been specially designed for endovascular procedures. It is called Specials Radiology, and is a combination X-ray room and operating room. The typical recovery involves an overnight stay in the hospital for observation. There is very little postoperative pain, and the patient is able to eat right away. The patient is typically discharged home after breakfast the day after the procedure, often less than 24 hours after being operated upon. The patient can resume normal activities right away. The main risk of the procedure is that a stroke will occur during the procedure, while the artery is being manipulated. Fortunately, this is a very rare occurrence. After the procedure, the patient will continue with lifestyle modifications, aspirin and Plavix, and routine ultrasound surveillance of both carotid arteries. Back to top
 VIDEO: click here to see an animated recreation of this technique
Carotid Artery Stenting — Before and After
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