Management of patients with symptomatic carotid artery occlusion

The annual risk of stroke in patients with symptomatic carotid artery occlusion (CAO) and impaired cerebral blood flow (CBF) is approximately 10%. Increased oxygen extraction fraction measured by positron emission tomography (PET) and low cerebrovascular reactivity assessed by transcranial Doppler is associated with an increased risk of recurrent ischemic stroke in these patients. Recently, other risk factors have been identified: (1) symptoms of purported hemodynamic origin; (2) ongoing symptoms in the presence of documented symptomatic CAO; (3) leptomeningeal collaterals visible on angiography; and (4) low NAA/choline ratio on magnetic resonance (MR) spectroscopy. Evidence is growing that a second extracranial-intracranial (EC-IC) bypass trial might be worthwhile in patients with symptomatic CAO. Probably, only patients with ongoing symptoms and compromised CBF should be included in such a trial. Current evidence based therapeutic options for patients with symptomatic CAO include antithrombotic medication and control of vascular risk factors. For stenosis of the contralateral internal or ipsilateral external carotid artery endarterectomy may be considered. Ongoing symptoms may cease after tapering of antihypertensive medication.