[Operation and angioplasty in cerebrovascular disorders]

Carotid endarterectomy until recently was performed to prevent the progression of a stenosis to an occlusion and hemodynamically induced strokes in patients with tight stenosis. Operation of ulcerated plaques or stenosis was supposed to prevent embolic stroke. The operation has no indication for a stenosis of the internal carotid artery (ICA) > 50% and < 90% in asymptomatic persons. Whether persons with an asymptomatic stenosis > 90% show a preventive effect of the operation is not known at this time. According to the Mayo-Clinic study, persons with asymptomatic ICA stenosis should be treated with aspirin to prevent myocardial infarction. Two large controlled trials have shown that endarterectomy can prevent stroke in patients with transient ischemic attacks (TIA) or minor stroke and an ICA-stenosis > 70%. This preventive effect is lost when the complication rate of the procedure is higher than 5% (mortality and morbidity). In patients with stenosis < 30% the operation has no preventive effect. Both studies continue to recruit patients with symptomatic stenoses between 30 and 70%. Patients with severe neurological deficits or a large lesion in CT should not be operated as would be patients with an acute stroke. The extra-intracranial bypass operation did not prevent stroke in patients with an occlusion of the ICA or severe stenosis or occlusion of the middle cerebral artery. Angioplasty has been applied to dilate stenoses of the subclavian artery in patients with subclavian-steal syndrome and disabling vertebro-basilar TIA. Angioplasty in the carotid artery is still an experimental procedure, which should only be applied in controlled trials.