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The decision to treat depends on the degree of stenosis. If the stenosis is less than 69% and asymptomatic, it can be managed with best medical therapy, which includes antiplatelet therapy, anti-lipid therapy, beta blockade, and risk factor modification.

  • If the stenosis is significant, greater than 70%, and the patient is a good operative candidate and/or there are symptoms of cerebrovascular insufficiency, then an operation such as carotid endarterectomy (CEA) or carotid angioplasty and stenting (CAS) may be considered.
  • If a carotid artery is occluded, there is no surgical or endovascular corrective treatment. These patients are given best medical therapy and monitored closely for contralateral carotid disease.
  • The decision to treat is based on patient symptomatology, operative risk, comorbidities, and benefit, which is stroke-free survival. The results of several clinical trials are considered in the decision-making process.
  • The North American Carotid Endarterectomy Trial (NASCET) and the Asymptomatic Carotid Atherosclerosis Study (ACAS) are the two major studies that demonstrated the efficacy of CEA in patients with symptomatic and asymptomatic high-grade carotid stenosis in stroke prevention over best medical therapy.

CEA is an open operation that has been performed since the 1950s and is still considered the gold standard in treating carotid stenosis. It carries a 1 to 2% risk of stroke and/or death. Most commonly, it is done under general anesthesia but may be done under local or regional anesthesia. Some surgeons will order intraoperative EEG monitoring. Use of an intraoperative shunt to supply blood flow during the clamping of the internal carotid artery is used to decrease ischemia. Patch angioplasty using a Dacron or bovine pericardial patch to close the endarterectomy site has been demonstrated to decrease the incidence of restenosis.

  • Anesthesia is reversed in the operating room (OR), the patient is checked for any neurologic deficit (e.g., difficulty waking from anesthesia, aphasia, clumsiness of movement, or paralysis of the contralateral side). If any of these exist, a Doppler exam is followed by immediate reoperation as it is assumed that thromboembolism from the endarterectomy site or residual plaque may be the culprit. Delay beyond even 1 hour decreases the chance of a successful reoperation.
  • A diffuse neurologic deficit is caused by intraoperative hypotension, causing a watershed infarct, a type of infarct that occurs in the territory between two major arteries in the brain.
  • Postoperative stroke occurring within the first 24 hours is presumed to be embolic. A CT scan is not helpful and delays the reoperation if there is a technical problem with the surgery or thrombolysis. If symptoms develop after the first 24 hours, a CT scan is done to rule out intracranial bleeding.