Definition

Carotid artery stenosis is a narrowing of the large carotid arteries in the neck that provide most of the blood supply to the brain. Also known as carotid artery disease, it is a major risk factor for the most common type of stroke, ischemic, which cuts off blood flow.

Causes

Atherosclerosis is a common cause of carotid artery stenosis. When cholesterol, fat, and other substances accumulate in the inner lining of an artery, plaque forms. The buildup of plaque narrows the artery passage, which reduces the flow of blood, oxygen, and other nutrients to the brain. This can lead to a stroke when one of the carotid arteries becomes too narrow.

Risk Factors

Factors that may increase the risk of developing this condition include:

  • High blood pressure
  • Smoking
  • High cholesterol level, especially high LDL
  • Diabetes or high blood sugar
  • Obesity
  • Increasing age

Symptoms

Symptoms, for carotid artery stenosis range from mild and temporary to severe and possibly permanent and include the following:

  • Blurred or loss of vision
  • Weakness
  • Numbness
  • Slurred speech
  • Loss of brain function
  • Inability to use one or more limbs

Conditions associated with these symptoms are:

  • Transient ischemic attack (TIA), a temporary condition lasting less than 24 hours; complete recovery following the event
  • Reversible ischemic neurological deficit (RIND), also temporary, but lasting longer than 24 hours; complete recovery following the event
  • Stroke
  • Any of these symptoms should prompt an emergency evaluation at the nearest hospital.

Diagnosis

A physician may discover carotid artery stenosis when symptoms are not present (asymptomatic stenosis). A bruit (pronounced "broot"), the abnormal sound of blood flowing through narrowed arteries, is detectable through a stethoscope or during a routine ultrasound screening that involves placing a probe on the side of the neck near the carotid arteries.

Advanced equipment used to monitor and diagnose carotid stenosis includes:

  • Carotid ultrasonography, also called carotid Doppler
  • Magnetic resonance imaging (MRI) or angiography (MRA)
  • Computer tomography angiography (CTA)
  • Cerebral angiography

Higher degrees of stenosis or the presence of any symptoms caused by the stenosis may indicate a need for definitive treatment. Even mild stenosis often requires modification of risk factors and medical treatments.

Treatment

For people with arteries narrowed less than 50 percent, physicians usually prescribe anti-platelet medicines such as aspirin or clopidogrel, sometimes in combination with anti-coagulants, to reduce the risk of ischemic stroke. The stenosis also may be treated by carotid endarterectomy (CEA) or carotid artery stenting (CAS) depending on the patient's general medical condition, age, the anatomy of the carotid artery, and past medical and surgical history.

A full discussion about the relative risks and benefits of CEA vs CAS must be individualized for each patient. In the Mount Sinai Department of Neurosurgery both CEA and CAS are performed in high volumes with outstanding clinical results. According to the American Heart Association, carotid endarterectomy has proven to be superior to medical management of symptomatic patients with arteries that are more than 70 percent narrowed, as well as in selected asymptomatic and symptomatic patients with lesser degrees of narrowing.

Dr. Joshua Bederson has extensive experience performing carotid endarterectomy with excellent results. The procedure takes place under general anesthesia. The carotid artery is opened (image A), the plaque is removed (B) and the artery is sewn back up again using microsurgical technique (C-E). Patients are monitored throughout the surgery using neurophysiological monitoring for added safety. Careful attention is paid to the skin closure to minimize scarring and leave a good cosmetic result. Patients are discharged the following morning and rapidly return to their normal activities depending on their preoperative symptoms.

Dr Aman Patel has extensive experience performing Carotid Artery Stenting at Mount Sinai. 

Prevention

Although the normal aging process and hereditary factors can contribute to narrowing of the arteries, lifestyle modifications can help lower the risk of stroke:

  • Cessation of smoking
  • Good blood pressure control
  • Weight management
  • Regular exercise
  • Blood sugar maintenance for diabetics
  • Limits on salt and saturated fat intake
  • Limits on alcohol intake to no more than two drinks a day for men, one for women

To learn more about carotid stenosis, carotid endarterectomy or carotid stenting, call the Mount Sinai Department of Neurosurgery at 212-241-2377.

Written by the Mount Sinai Department of Neurosurgery.

This information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. Call you health care provider immediately if you think you may have a medical emergency. Always seek the advice of your physician or other qualified health provider before starting any new treatment or with any questions you may have regarding a medical condition.