The carotid arteries are the main source of blood flow to the brain. There are two of them, and they branch off of the aorta in the chest on either side of the neck up into the brain. A healthy artery is open and allows the blood to flow to the brain. If the inside of the artery becomes narrow or rough, a patient is susceptible to stroke. As it becomes narrower or rougher, the risk is higher.
Patients with high blood pressure, diabetes and other diseases are at risk, as are patients who are overweight or smoke, because these conditions can cause plaque to build up on the insides of the artery wall. As more plaque forms, the artery becomes narrower and the walls become rough, which can cause blood clots to form. Both of these conditions can decrease the flow of necessary blood and oxygen to the brain. Very small blood clots or bits of this plaque (emboli) can break off and travel through the carotid artery, and these can get stuck in the smaller blood vessels in the brain, blocking blood flow and causing a stroke. Larger emboli can cut off blood flow to parts of the brain, too. Without oxygenated blood, that part of the brain dies, and the patients have difficulty, depending on which part of the brain was affected. Some patients have trouble walking, some can’t speak, and some die. People with relatives who have had strokes are at a higher risk.
Symptoms of carotid artery disease can include:
- Slurred Speech
- Vision Problems
To evaluate your carotid arteries, the doctor may order a scan that uses sound waves to make images of the carotid arteries. This is called an ultrasound. During the test, a sensor is gently pressed against the neck, and an image showing how severe the narrowing is forms on a monitor. Another test is called angiography. In angiography, the doctor injects a dye into the arteries as X-rays are taken. Sometimes a test called magnetic resonance angiography (MRA) is ordered. This test makes an image of the carotid arteries without using X-rays. These tests also can show damage to the brain from a past stroke.
Not all patients need surgery right away. If patients have mild narrowing but have had mini-strokes, surgery may be needed. If the narrowing is more severe, even though the patient may not have any symptoms of a mini-stroke, surgery still may be needed to prevent a stroke.
The typical surgery is a carotid endarterectomy. This surgery removes the plaque, opening and smoothing out the inside of the carotid artery. Like any surgery, carotid endarterectomy has risks and complications, such as bleeding, temporary trouble swallowing or speaking, heart attack or stroke.
Most of the time, the surgery is done with the patient under general anesthesia. An incision is made near one of the arteries in your neck. Then an incision is made in the artery itself. Blood is rerouted during the surgery using a small tube, which allows blood to continue flowing to the brain while the doctor cleans out the artery. If the blood flow is strong in the other carotid artery, sometimes the small tube or shunt is not used. The surgery takes about two hours. The doctor carefully loosens the plaque from the artery walls and then removes it. The shunt is removed and the artery is closed with stitches; then the skin is closed. Sometimes a small tube is left in place to help with any drainage that occurs, and a dressing is placed over the incision.
Patients go to the recovery room or intensive care unit for the first few hours after surgery. It is best to not try move their head and while some discomfort is normal…medication is available to help. Most patients are up and walking again within 24 hours. Post surgery is followed up with a meeting with the surgeon days after the operation to assess the recovery.