Cardiovascular Medicine Book

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Carotid BruitAka: Carotid Artery Stenosis, Carotid Stenosis

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  1. See Also
    1. Transient Ischemic Attack
    2. Arteriosclerotic Carotidynia
  2. Technique
    1. See Arterial Bruit
  3. Interpretation of carotid bruit
    1. Degree of stenosis by atherosclerotic Plaque
      1. Minimum stenosis causing bruit: 50% (<3 mm lumen)
      2. Prolonged, high-pitched bruit: >75% (1.5 mm lumen)
    2. Location
      1. Plaque involves posterior wall of common carotid
      2. Affects bifurcation and flow into internal carotid
      3. Risk of distal thrombus formation in internal carotid
    3. Carotid bruit associated risk of stroke at 1 year
      1. Asymptomatic carotid bruit: 1% risk at 1 year
      2. Transient Ischemic Attack history: 1.7% risk
      3. Other studies question bruit significance
  4. Symptoms
    1. Contralateral weakness or numbness
    2. Ipsilateral blindness
    3. Dominant hemisphere involvement
      1. Dysphasia
      2. Aphasia
      3. Apraxia
  5. Imaging: Preferred First-Line Studies
    1. Carotid Artery Duplex Ultrasonography
      1. Standard first-line diagnostic tool for carotid stenosis
      2. Less expensive than MRA
      3. Accuracy for diagnosing severe carotid stenosis
        1. Test Sensitivity: 86%
        2. Test Specificity: 87%
    2. Carotid Magnetic Resonance Angiography (MRA)
      1. Better than ultrasound at defining carotid anatomy
      2. Accuracy for diagnosing severe carotid stenosis
        1. Test Sensitivity: 95%
        2. Test Specificity: 90%
    3. References
      1. Nederkoorn (2003) Stroke 34:1324
  6. Imaging: Other studies
    1. CT Angiography with 3D reconstruction
      1. Requires intravenous iodinated contrast exposure
      2. Emerging technology that has not been fully evaluated
      3. Significant radiation exposure
    2. Angiography
      1. Gold standard which allows evaluation of the entire carotid system
      2. Invasive procedure with risk of neurologic complications
      3. Now used primarily to resolve imaging discrepancies in perioperative period
  7. Management: Symptomatic Carotid Stenosis
    1. Endarterectomy carries risk of significant morbidity
      1. Cognitive changes may be difficult to discern
      2. Risk of CVA within 30 days of procedure: 7%
    2. Symptomatic patient with carotid stenosis >70%
      1. Intervention offers greatest benefit
      2. Significant benefit from carotid endarterectomy
      3. Benefits include patients over age 75 years
    3. Symptomatic patient with carotid stenosis 50 to 69%
      1. Benefit from carotid endarterectomy
      2. Benefits include patients over age 75 years
    4. Symptomatic patient with carotid stenosis <50%
      1. No benefit from carotid endarterectomy
      2. See Prevention of Ischemic Stroke
  8. Management: Asymptomatic Carotid Stenosis >60%
    1. Medical therapy: Indicated if carotid stenosis <80%
      1. Overall CVA Risk on medical therapy: 12% CVA 5 year risk
      2. See Prevention of Ischemic Stroke
      3. Hypertension control (typical goal is <130/80)
        1. Exercise caution with bilateral carotid stenosis
      4. Hyperlipidemia control with Statins
      5. Antiplatelet options
        1. Clopidogrel (Plavix)
          1. Do not use concurrently with Aspirin
        2. Aspirin
        3. Aspirin with Dipyridamole (Aggrenox)
    2. Surgical Procedures: Indicated if carotid stenosis >80%
      1. Overall CVA Risk on surgical therapy: 6% CVA 5 year risk
      2. Surgical Options
        1. Carotid endarterectomy or
        2. Angioplasty, stent, distal protection
          1. As effective as carotid endarterectomy
          2. May be preferred in patients at high risk of complications due to comorbidity
          3. (2006) Lancet 368:1239
          4. Park (2006) Am J Surg 192:583
    3. References
      1. Halliday (2004) Lancet 363:1491
  9. References
    1. Alamowitch (2001) Lancet 357:1154
    2. Ellis (1992) Eur J Vasc Surg 6(2):172
    3. Gutierrez (1985) Am Surg 51(7):388
    4. Rothwell (2003) Lancet 361:107

Carotid Stenosis (C0007282)

Definition (MSH)Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp822-3)
ConceptsDisease or Syndrome (T047)
EnglishCarotid Artery Narrowing, Carotid Artery Narrowings, Carotid Artery Stenoses, Carotid Artery Stenosis, Carotid Stenoses, Carotid Stenosis
Spanishestenosis carotídea, estenosis carotidea, estenosis de la arteria carótida, estenosis de la arteria carotida, estrechamiento de la arteria carótida, estrechamiento de la arteria carotida
CreditsDerived from the NIH UMLS (Unified Medical Language System)



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