title: Predictive value of asymptomatic cervical bruit for carotid artery disease in coronary artery surgery revisited.
abstract: OBJECTIVE
  To investigate the predictive value of asymptomatic cervical bruit for detecting internal carotid artery disease in consecutive patients undergoing coronary artery bypass grafting (CABG).
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  Tertiary referral university hospitals.
  
  
  METHODS
  153 consecutive patients (mean age 57 years) undergoing CABG, without previous history of cerebrovascular events.
  
  
  METHODS
  Patients underwent detailed pre-operative work-up, including coronary angiography and carotid artery duplex scanning. Internal carotid artery diameter stenosis was graded as A: normal; B: < 15%; C: 15%-50%; D: 50-80%; D+: > 80-99% and E=complete occlusion.
  
  
  RESULTS
  72 patients (47.1%) (95% CI: 39%, 55%) had no evidence of internal carotid artery stenosis; 81 (52.9%) (95% CI: 44.9%, 60.9%) had varying grades of disease, unilateral or bilateral. Cervical bruit was detected in 12/153 patients (7.8%) (95% CI: 3.5%, 12.1%) of whom all but one (0.7%) had varying grades of internal carotid artery disease; of these, 4 patients had bilateral cervical bruit (2.6%) (95% CI: 0.06%, 5.2%). The sensitivity, specificity, positive and negative predictive values and overall accuracy of cervical bruit for detection of > or = 50% internal carotid artery stenosis were 23.5%, 95.8%, 25%, 95.5% and 91.8%, respectively. The relative risk of > or = 50% stenosis ipsilateral to cervical bruit in 306 sides was 5.58 (95% CI: 2.0, 15.0) and the odds ratio 7.1 (95% CI: 2.0, 25.0).
  
  
  CONCLUSIONS
  Asymptomatic cervical bruit proved a highly specific clinical sign for detection of internal carotid artery stenosis, whether haemodynamically significant (> or = 50%) or otherwise, in patients undergoing myocardial revascularisation. This was matched by a high negative predictive value and overall accuracy for flow limiting atheroma (> or = 50% stenosis). Yet, steering carotid investigations on the basis of cervical bruit alone would result in > or = 80% internal carotid artery stenosis remaining undetected in 3% of overall patients, in whom cervical bruit is absent.
authors.affiliation: Academic Vascular Unit, St Mary's Hospital, Imperial College, London, UK. Sonecha@btinternet.com
authors.forename: T N
authors.initials: TN
authors.lastname: Sonecha
authors.forename: K T
authors.initials: KT
authors.lastname: Delis
authors.forename: M Y
authors.initials: MY
authors.lastname: Henein
mesh_terms: D000368:Aged; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016893:Carotid Stenosis / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D016022:Case-Control Studies; D002561:Cerebrovascular Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome; D018616:Ultrasonography, Doppler, Duplex