CAROTID ENDARTERECTOMY - a patient's guide
What is it?
Carotid endarterectomy is a surgical procedure performed in order to treat blockage of the carotid arteries in the neck. Significant narrowing of these neck arteries, which are the dominant blood supply to the brain, can increase the chance of suffering a stroke.
Patients with carotid artery blockage may or may not have symptoms prior to the onset of a stroke. The five main risk factors for this blockage are cigarette smoking, high blood pressure (hypertension), high cholesterol, high blood sugar (diabetes mellitus), and a strong family history of strokes or other artery problems such as heart attacks.
Most carotid artery blockages are noted on routine physical examination when a doctor listens to the patient's neck with a stethoscope and detects an abnormal sound called a bruit.
The next step in evaluation is a Doppler test in which the neck arteries are imaged with an ultrasound machine. By looking at the carotid arteries using this screening test, an approximate measure of the degree of blockage can be made. Not all bruits are necessarily pathologic, meaning that the presence of a bruit does not always signal a significant blockage in the artery.
Carotid artery blockages are sometimes detected after a patient either has a stroke or a mini-stroke (transient ischemic attack or TIA). The difference between these two latter events is a matter of time; a TIA is followed by neurological recovery within 24 hours, while a stroke leads to loss of neurological function for greater than 24 hours. Symptoms of TIAs or strokes include loss of control or motion of an arm or leg, sudden loss of vision in one eye, or difficulty speaking.
If a significant blockage is detected, the next step is consultation with the patient's primary care physician and possibly a surgeon. One must decide at this point the patient's risk factors for surgical treatment. In general, if the degree of blockage is 70% or greater, surgical intervention is indicated. Further diagnostic testing with a regular arteriogram (angiogram) or Magnetic Resonance Angiography (MRA) can then be performed to confirm the Doppler finding prior to surgery.
Considerations for surgery
There has been some controversy in the past about the indications for carotid endarterectomy. Numerous studies on the surgical versus medical treatment of carotid artery blockage have been performed, and have yielded guidelines that can be applied to treatment of this problem. However, the results of these trials involve a great number of people with different risk factors, and the decision to proceed with surgical intervention must be individualized to each patient.
In general, patients with 70% or greater blockage of the carotid arteries are considered for surgical repair, even if they have had no previous symptoms. The role of surgery is to diminish the risks of stroke. However, surgery itself carries a 1-2% risk of stroke and 1-2% risk of heart attack. A surgeon performing carotid surgery must achieve similar or better results in order for the procedure to be of benefit to patients.
Patients with symptoms of carotid artery disease and greater than 50% blockage also benefit from surgery. The important factors in a surgical program's success include careful selection of patients for the procedure, training in vascular surgery, and a high volume of carotid endarterectomies performed per year by the surgeon. In addition, patients with carotid artery blockage should be treated with some form of anti-platelet therapy such as one aspirin a day, whether or not they undergo surgery.
How is the procedure carried out?
An incision of approximately 6-8 cm in size is made on the side of the neck where the diseased artery is located.
There are several different ways to perform the procedure, but in essence, the buildup of blockage within the artery is carefully scraped out during the surgery. The artery is then closed using fine sutures. The procedure takes approximately two hours, and the patient is then closely monitored overnight. Most patients can be discharged from the hospital within 1-2 days after surgery.
After surgery, we ask patients not to drive for approximately one week due to neck stiffness. Return to a normal routine is otherwise encouraged as soon as the patient feels comfortable. Long-term results from the surgery are excellent, within minimal physical discomfort.
Carotid endarterectomy is a safe and effective procedure for stroke prevention. Success depends on appropriate patient selection and a skilled surgical team.
The long-term outcome of patients with carotid artery disease rests on modifying risk factors for circulation problems that can also lead to blockage in the heart and leg arteries. These modifications include absolute cessation of cigarette smoking, control of high blood pressure and cholesterol, and diabetic management. In addition, regular cardiovascular exercising is promoted for overall circulation improvement.
We encourage patients to take one half (150 mg) or full strength (300 mg) aspirin a day, starting as soon as significant carotid artery blockage is detected, and to continue this therapy even after surgery.
Non-operative management of carotid artery blockage, that is not severe enough to warrant surgery, includes control of risk factors for artery disease, anti-platelet treatment, and surveillance Doppler ultrasound evaluations at 6 month to 1 year intervals.