//fpnotebook.com/
Carotid Bruit
Aka: Carotid Bruit, Carotid Artery Stenosis, Carotid Stenosis- See Also
- Technique
- See Arterial Bruit
- Interpretation: Carotid Bruit
- Findings in which Carotid Bruit is more suggestive of significant carotid lesion
- Diastolic component is the only characteristic reliably specific for significant Carotid Bruit
- Carotid Bruit AND symptoms suggestive of Carotid Stenosis
- Degree of stenosis by atherosclerotic Plaque
- Minimum stenosis causing bruit: 50% (<3 mm lumen)
- Prolonged, high-pitched bruit: >75% (1.5 mm lumen)
- Location
- Plaque involves posterior wall of common carotid
- Affects bifurcation and flow into internal carotid
- Risk of distal thrombus formation in internal carotid
- Carotid Bruit associated risk of stroke at 1 year
- Asymptomatic Carotid Bruit: 1% risk at 1 year
- Transient Ischemic Attack history: 1.7% risk
- Other studies question bruit significance
- Carotid Bruit has poor efficacy
- Test Sensitivity: 40% for those with >50% Carotid Stenosis
- False Positives: 10% with Carotid Bruits have <50% Carotid Stenosis
- References
- Brown (2017) Stroke and Cerebrovascular Disease Update, Mayo Clinical Reviews, Rochester
- Findings in which Carotid Bruit is more suggestive of significant carotid lesion
- Symptoms
- Imaging: Preferred First-Line Studies
- Carotid Artery Duplex Ultrasonography
- Standard first-line diagnostic tool for Carotid Stenosis
- However, do not make clinical decisions based on Ultrasound alone (due to False Positives)
- Confirm findings with either a MRA or CTA
- Less expensive than MRA
- Accuracy for diagnosing severe Carotid Stenosis
- Test Sensitivity: 86%
- Test Specificity: 87%
- Standard first-line diagnostic tool for Carotid Stenosis
- Carotid Magnetic Resonance Angiography (MRA)
- Better than Ultrasound at defining carotid anatomy
- Accuracy for diagnosing severe Carotid Stenosis
- Test Sensitivity: 95%
- Test Specificity: 90%
- References
- Carotid Artery Duplex Ultrasonography
- Imaging: Other studies
- CT Angiography with 3D reconstruction
- Requires intravenous iodinated contrast exposure
- Emerging technology that has not been fully evaluated
- Significant radiation exposure
- Angiography
- Gold standard which allows evaluation of the entire carotid system
- Invasive procedure with risk of neurologic complications
- Now used primarily to resolve imaging discrepancies in perioperative period
- CT Angiography with 3D reconstruction
- Management: Symptomatic Carotid Stenosis
- Endarterectomy carries risk of significant morbidity
- Cognitive changes may be difficult to discern
- Risk of CVA within 30 days of procedure: 7%
- Symptomatic patient with Carotid Stenosis >70%
- Intervention offers greatest benefit (17% Absolute Risk Reduction at 2 years per NASCET study)
- Significant benefit from carotid endarterectomy
- Benefits include patients over age 75 years
- Symptomatic patient with Carotid Stenosis 50 to 69%
- Benefit from carotid endarterectomy
- Benefits include patients over age 75 years
- Symptomatic patient with Carotid Stenosis <50%
- No benefit from carotid endarterectomy
- See Prevention of Ischemic Stroke
- Endarterectomy carries risk of significant morbidity
- Management: Asymptomatic Carotid Stenosis >60%
- Medical therapy: Indicated if Carotid Stenosis <80%
- Overall CVA Risk on medical therapy: 12% CVA 5 year risk
- See Prevention of Ischemic Stroke
- Hypertension control (typical goal is <130/80)
- Exercise caution with bilateral Carotid Stenosis
- Hyperlipidemia control with Statins
- Antiplatelet options
- Aspirin
- Other antiplatelet agents are not recommended
- Clopidogrel (Plavix)
- Do not use concurrently with Aspirin
- Aspirin with Dipyridamole (Aggrenox)
- Clopidogrel (Plavix)
- Surgical Procedures: Indicated if Carotid Stenosis >80%
- Overall CVA Risk on surgical therapy: 6% CVA 5 year risk
- Relative contraindications to carotid endarterectomy
- Women show less benefit in asymptomatic Carotid Stenosis
- Life Expectancy <5 years
- Active cardiovascular disease
- Age over 80 years
- Concomitant intranial stenosis
- Contralateral Carotid Stenosis
- Surgical Options
- Carotid endarterectomy or
- Angioplasty, stent, distal protection
- As effective as carotid endarterectomy
- May be preferred in patients at high risk of complications due to comorbidity
- Recent European trials (SPACE and EVA-3S) showed high complication rate
- However these trials did not consistently use distal protection devices
- Medical therapy: Indicated if Carotid Stenosis <80%
- References