Carotid Artery Disease

• Atherosclerosis is common at the bifurcation of the common carotid artery
• Stenosis of the internal carotid artery is a potentially treatable cause of
  • Ischaemic stroke
  • Transient ischaemic attack
  • Retinal infarction
• A patient with an asymptomatic 50% carotid stenosis has 1-2% per year risk of a stroke
• The risk of stroke increases with the degree of stenosis
• Once a stenosis has become symptomatic the risk of a stroke is further increased
• Once an ischaemic stroke has occurred the risk of further stroke is ~10% in the first year and ~5% in subsequent years

Assessment of stenosis

• Carotid bruits are an unreliable guide to severity of stenosis
• May be absent in patients with severe stenosis

Duplex ultrasound

• Doppler recordings allow assessment of flow at stenosis
• Also allows imaging of arterial anatomy

Carotid angiography

Magnetic resonance angiography

Medical Management

• Stop smoking
• Pharmacological treatment of hypertension and diabetes
• Prophylactic aspirin
  • Asprin prevents around 40 'vascular events' per 1000 patients treated for 3 years
  • It should be started at 175-150 mg daily once ischaemic stroke confirmed by CT
  • It should also be given to those with asymptomatic stenoses
  • The combination of aspirin and dipyridamole is no more effective than aspirin alone.

Surgery for asymptomatic stenosis

Asymptomatic Carotid Atherosclerosis Study

• 1662 patients with >60% reduction in luminal diameter
• Randomised to either
  • Endarterectomy + medical treatment (aspirin 300 mg)
  • Medical treatment alone
• Risk of ipsilateral stroke over 5 year period was reduced (5% vs. 11%) in surgery group
• 2.3% in surgery group had stroke within 30 days of surgery
• 0.4% in medical group had stroke in same time period
• Overall, benefit for those with asymptomatic stenosis but only the presence of a low perioperative complication rate.

Surgery for symptomatic stenosis

Two large trials have been published

North American Symptomatic Carotid Endarterectomy Trial (NASCET)

• Compared endarterectomy plus medical treatment in those patients with
• Non-disabling stroke in 4-6 months prior to surgery
• Severe (70-99%) ipsilateral stenosis
• The risk of stroke or death over 2 years was reduced (9% vs. 26%) in surgery group
• 5.8% randomised to surgery had stroke within 30 days
• Benefit also seen in those with >50% stenosis but not to same degree

European Carotid Surgery Trial (ECST)

• ECST risk of stroke or death over 3 years was reduced (12% vs. 22%) in surgery group
• 7.5% randomised to surgery had stroke or died within 30 days of operation
• In those with mild (0-30%) and moderate (30-60%) symptomatic stenoses there was benefit from surgery
• Overall, In those with symptomatic stenoses
• Best results are seen in those with more severe stenoses
• Benefit only seen in institutions with low perioperative stroke and death rate
• Surgery indicated in those with severe stenosis (>70%) that have recently become symptomatic
• Operation should be performed by experienced surgeon
• Centres should audit their results and have a perioperative stroke rate of < 7%
• Angina and hypertension should be well controlled pre-operatively
• If patient selection is poor or complication rate high then there will be no benefit from surgery.

Carotid Endarterectomy

Carotid angioplasty

Dr. Pankaj Patel a vascular surgeon has expertise in peripheral vascular diseases, varicose veins and deep vein thrombosis