Clinical significance of asymptomatic neck bruits.

The value of neck bruits as indicators of underlying carotid artery disease was assessed by correlating the results of carotid Doppler examination with auscultation in 336 patients with asymptomatic bruits. Also, the separate findings of auscultation by two physicians were compared for agreement in the quality and location of the bruits. Levels of agreement between the physicians in the clinical examination were acceptable for the presence and site of the neck bruits, but were unacceptable for the intensity, pitch, and duration. Unilateral bruits in the upper neck indicated underlying internal carotid artery (ICA) stenosis detectable by carotid Doppler (greater than 35% stenosis) in 61%, whereas only 11% of patients with bruits localized to the supraclavicular area had ICA stenosis. "Silent" contralateral ICA stenosis was detected by Doppler in 28% of patients with unilateral cervical bruits. Bilateral cervical bruits were the most powerful predictors (76%) of underlying ICA stenosis detectable by Doppler. Neck bruits are valuable indicators of underlying carotid artery disease, but Doppler ultrasound examination adds significantly to clinical accuracy.