What is a Carotid Bruit?

Has your doctor ever placed the bell of the stethoscope on either side of your neck, asked you to hold your breath – and then listened? Chances are your doctor was listening for a carotid bruit. What is a carotid bruit and what does it mean if you have one?

What is a Carotid Bruit?

A carotid bruit is an abnormal sound that can be heard when a stethoscope is placed on either side of the neck on top of the carotid arteries which run from the heart up into the brain. Normally, blood flows smoothly through these blood vessels, but when the vessels are blocked or narrowed, the flow of blood becomes turbulent – leading to an abnormal sound. This abnormal sound can be a warning sign of a stroke since an obstruction or narrowing can decrease blood flow to the brain. In some, cases a carotid artery bruit can be heard in a normal person – usually younger people.

What Happens if Your Doctor Hears a Carotid Artery Bruit Sound During an Exam?

It’s very difficult to say whether a carotid bruit is “innocent” or caused by narrowing in the artery based on physical exam. That’s why most doctors order additional studies when they hear a carotid artery bruit. One test that’s used is an ultrasound study of the carotid arteries in the neck. This is a non-invasive, painless procedure that uses sound waves to look for obstruction or narrowing in the arteries.

If an ultrasound test shows no obstruction or narrowing of the arteries, a carotid artery bruit may be called innocent since it doesn’t increase the risk for stroke. Innocent carotid bruits are more common in children and young people who have a faster heart rate and greater flow of blood through the carotid arteries. Innocent carotid bruits require no treatment.

What If a Carotid Bruit Isn’t Innocent?

If an ultrasound shows obstruction or narrowing in one or both of the carotid arteries, doctors sometimes recommend carotid angioplasty or a surgery called carotid endarterectomy to reduce the risk of stroke. Whether or not these procedures are recommended will depend on how narrow the carotid arteries are and whether or not the narrowing is causing symptoms. Some people with narrowing of the carotid arteries will have stroke-like symptoms that come and go – and these people need treatment because their risk for stroke will be higher.

Recent studies show that a carotid artery bruit on physical exam may be a marker for an increased risk of heart disease. In fact, an analysis of a variety of studies showed that carotid artery bruits are associated with a higher risk for heart attack. This makes sense. If the carotid arteries are narrowed with plaque, there’s a good chance that other vessels such as the coronary arteries that carry blood to the heart are too.

What is a Carotid Bruit?: The Bottom Line?

A carotid bruit requires further investigation – usually an ultrasound study. In some cases, it can indicate a higher risk of stroke or heart disease, but in young people it may be a normal finding.

References:

http://cme.medscape.com/viewarticle/574326
Merck Manual. Eighteenth Edition.