Surgery for patients TIA's

Surgery on the carotid arteries (carotid endarterectomy) is a very effective preventative of stroke. If a patient has TIA's, the carotid artery is narrowed by 70% or more on the side and in the area of the brain affected by the TIA's, then surgery on the carotids may the the most effective preventative of a future stroke. If the artery is narrowed by 50-69%, surgery appears to be about as effective as medical treatment. If the artery is narrowed by less than 50%, medical treatment is superior.

Surgery in completed strokes

Once a stroke has occurred there is less of a role for surgery. In some patients with mild strokes, carotid endarterectomy may be suggested to reeduce the risk of a subsequent severe stroke if the carotid in the area of the brain affected is narrowed by 70% or more. In this situtation, many surgeons prefer to wait for at least 6 weeks after the acute stroke before operating as there is some evidence that early operation increases the risk of the surgery itself causing problems.

Surgery for asymptomatic disease

Patients at times are found to have narrowed carotids who have never had a TIA or stroke related to the narrowing. There is some evidence that even these patients may, in certain circumstances, do better with surgery. However, unlike surgery for patients with TIA's, the benefit is not as dramatic. The stroke risk is only about 2% per year from asymptomatic carotid artery disease. The reduction in stroke risk in patients with asymptomatic stenosis is such that about 1 more stroke out of 19 will be prevented by doing surgery compared to doing medical treatment alone. Since carotid artery surgery is not without risks, the patient must fully understand the risk/benefit tradeoff when deciding on carotid endarterectomy for asymptomatic disease.

Complications of carotid surgery

• The most significant risk of carotid artery surgery to prevent stroke is that the surgery may actually precipitate a stroke. In performing the surgery, the vessel's blood flow is temporarliy compromised. This can cause a stroke. Alternatively a piece of plaque (hardened artery) may break off and flow up to the brain. Fortunately, the risk of this occuring is not common (typically 2-5% of cases) and this risk is lower than the 2-3 year risk of stroke in symptomatic narrowing of the aretry if surgery is not done.

• Heart attack (myocardial infarction). Most deaths that occur during a carotid endarterectomy are caused by a heart attack.
• Breathing difficulties (common to any surgery).
• Infection (common to any surgery).
• Injury to nerves (usually causing vocal cord paralysis and problems with managing saliva and tongue movement).
• Bleeding within the brain.
• Plaque buildup, which may redevelop as a complication between 5 months and 13 years after surgery.
• Death. (common risk to any surgery)