title: Carotid bruit for detection of hemodynamically significant carotid stenosis: the Northern Manhattan Study.
abstract: OBJECTIVE
  The prevalence of carotid bruits and the utility of auscultation for predicting carotid stenosis are not well known. We aimed to establish the prevalence of carotid bruits and the diagnostic accuracy of auscultation for detection of hemodynamically significant carotid stenosis, using carotid duplex as the gold standard.
  
  
  METHODS
  The Northern Manhattan Study (NOMAS) is a prospective multiethnic community-based cohort designed to examine the incidence of stroke and other vascular events and the association between various vascular risk factors and subclinical atherosclerosis. Of the stroke-free cohort (n=3298), 686 were examined for carotid bruits and underwent carotid duplex. Main outcome measures included prevalence of carotid bruits and sensitivity, specificity, positive predictive value, negative predictive value and accuracy of auscultation for prediction of ipsilateral carotid stenosis.
  
  
  RESULTS
  Among 686 subjects with a mean age of 68.2 +/- 9.4 years, the prevalence of >/=60% carotid stenosis as detected by ultrasound was 2.2% and the prevalence of carotid bruits was 4.1%. For detection of carotid stenosis, sensitivity of auscultation was 56%, specificity was 98%, positive predictive value was 25%, negative predictive value was 99% and overall accuracy was 97.5%.
  
  
  CONCLUSIONS
  In this ethnically diverse cohort, the prevalence of carotid bruits and hemodynamically significant carotid stenosis was low. Sensitivity and positive predictive value were also low, and the 44% false-negative rate suggests that auscultation is not sufficient to exclude carotid stenosis. While the presence of a bruit may still warrant further evaluation with carotid duplex, ultrasonography may be considered in high-risk asymptomatic patients, irrespective of findings on auscultation.
authors.affiliation: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA. eratchf@jhmi.edu
authors.forename: Elizabeth V
authors.initials: EV
authors.lastname: Ratchford
authors.forename: Zhezhen
authors.initials: Z
authors.lastname: Jin
authors.forename: Marco R
authors.initials: MR
authors.lastname: Di Tullio
authors.forename: Maya J
authors.initials: MJ
authors.lastname: Salameh
authors.forename: Shunichi
authors.initials: S
authors.lastname: Homma
authors.forename: Robert
authors.initials: R
authors.lastname: Gan
authors.forename: Bernadette
authors.initials: B
authors.lastname: Boden-Albala
authors.forename: Ralph L
authors.initials: RL
authors.lastname: Sacco
authors.forename: Tatjana
authors.initials: T
authors.lastname: Rundek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001314:Auscultation / Q000379:methods*; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016893:Carotid Stenosis / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D004452:Echocardiography / Q000379:methods; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D015995:Prevalence; D011859:Radiography; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods