Clogged Neck Arteries

When you need a screening test—and when you don’t

There are two large arteries in the neck, one on each side. They are the carotid arteries, and they carry blood to the brain. If one of them is narrowed or blocked, it can lead to a stroke.

Doctors can test for a narrowed carotid artery, but it’s usually not a good idea. In fact, the test may do more harm than good. Here’s why.

Blocked carotid arteries are not a common stroke risk.

Only 1/2 to 1 percent of U.S. adults have a narrowed carotid artery. Even if you have the condition, it’s not likely to cause a stroke unless you have other symptoms or risk factors too.

Most people are better off getting screened and treated for the major stroke risk factors:

  • Smoking
  • High blood pressure
  • High cholesterol
  • Diabetes

The tests are not very accurate.

There are two main screening tests for blocked carotid arteries:

  • An ultrasound uses sound waves to make a picture of the arteries.
  • Your doctor may use a stethoscope to listen for an abnormal sound from the arteries.

Neither of these tests is accurate. And both lead to many false-positive results. A false-positive result says you have the condition when you actually don’t.

Follow-up tests and surgery have risks.

False-positives can lead to unneeded follow-up tests and surgery. These can cause serious harm.

For example, a false-positive result can lead to angiography. In this test, a dye is injected into the carotid arteries. The test itself has a small risk of causing a stroke.

Or you might get surgery to remove a blockage that doesn’t exist. The surgery can cause bleeding, infection, nerve injury, stroke, heart attack, or even death.

Don’t pay for a test you don’t need.

The test is often offered at health fairs, senior centers, and other public locations. Before you pay for it, ask your doctor if you need it. If you really do need it, your health plan may pay. Your plan is more likely to pay if:

  • Your doctor orders it.
  • You get it in an office or lab that is part of your health plan.
  • You have other symptoms or risk factors for stroke.

When is it a good idea to get a carotid ultrasound?

You may need the test if:

  • You have already had a stroke or mini-stroke (transient ischemic attack, or TIA).
  • You have sudden symptoms of stroke or mini-stroke, including:
    • Weakness or numbness on one side of the face or body
    • Trouble seeing from one eye
    • Confusion
    • Slurred or slow speech
    • Difficulty using or understanding words
    • Dizziness, and loss of balance or coordination

This report is for you to use when talking with your health-care provider. It is not a substitute for medical advice and treatment. Use of this report is at your own risk.

© 2015 Consumer Reports. Developed in cooperation with the American Academy of Family Physicians for Choosing Wisely, a project of the ABIM Foundation.