Carotid Bruit

Bruit Definition

Bruit is a murmur or unusual blowing sound heard while auscultating a carotid artery or the aorta. Less commonly, it can be auscultated over the liver or thyroid. The bruit sound is produced by blood turbulence in a narrow or partially occluded artery. The specific character of the bruit, its location, and its timing are all of diagnostic importance. Bruits are usually low frequency sounds which are heard best with the bell of a stethoscope.

Carotid Artery Bruit

Carotid stenosis, sometimes called carotid artery disease, is a narrowing of the inner wall of the carotid artery. The narrowing is usually caused by deposits of cholesterol and fatty substances. The sound is auscultated with a stethoscope. The carotid artery is the large artery on both sides of the neck. The internal carotid artery supplies the brain and the external carotid artery supplies the face. The fork of the internal and external artery is a common site for atherosclerosis.

Clinically, risk of stroke from carotid stenosis is evaluated by the presence or absence of symptoms and the degree of stenosis on imaging. Auscultation can also be used for preliminary evaluation of carotid artery disease, to be followed by ultrasound imaging.

carotid artery stenosis

ICD-10 Code


Lessons on Carotid Bruit

We have created a short course on carotid bruit sounds. The cases provide a content for practicing carotid artery auscultation. Each case consists of multiple pages which summarize patient history, heart and carotid bruit sounds, lab results and diagnosis.

Course Overview

A bruit is caused by turbulent blood flow in an artery which supplies blood to the brain. Increased stenosis of a carotid artery results in increased duration, intensity, and pitch of the bruit. A carotid bruit and a basal heart murmur are easily confused. Because the sounds radiate throughout the body, a heart murmur will be heard, with reduced intensity, at the auscultation points above the clavicle and a carotid bruit will be heard (again with reduced intensity) at the auscultation points below the clavicle. If the intensity of sound is greater above the clavicle it is most likely a carotid bruit. If it is louder below the clavicle it is most likely a heart murmur. Use either the bell or the diaphragm when listening for the carotid bruit, at a point just lateral to the Adam's apple. Listen for the murmur of aortic stenosis at the second right intercostal space (2RICS). An early systolic bruit is associated with a 50% decrease in carotid artery luminal diameter. A pansystolic bruit is associated with a 60% reduction in luminal diameter. A pansystolic bruit that extends into early diastole is associated with a decrease in luminal diameter of 70% to 80%. The identification of a carotid artery bruit using a stethoscope should always be followed up with an ultrasound examination of both carotid vessels due to the limited accuracy of an examination with a stethoscope. Begin Course