Background: Stroke is the most common cause of disability in Norway. Most strokes are ischemic, and 25-30% are caused by emboli from atherosclerotic plaques in pre-cerebral arteries. The aim of this study was to review the literature on effectiveness of stroke prevention by surgical and endovascular treatment of carotid bifurcation stenoses.
Material and methods: Search of the PubMed and Cochrane Library. Relevant textbook chapters and personal experience have also supported the evaluation.
Results and interpretation: Prevention of stroke by carotid endarterectomy is documented in several large randomised controlled trials. For carotid stenoses with reduced diameters of more than 50%, a significant reduction of 5-year stroke risk is achieved with surgery and best medical treatment, compared to best medical treatment alone. The benefit is greatest with symptomatic stenoses, especially if surgery is performed shortly after onset of symptoms. Patients with transient ischemic attack (TIA), minor stroke or amaurosis fugax should without delay be referred to an ultrasound examination of the carotid. Surgery as soon as possible is indicated if > 70% stenosis is found, and for men also with moderate stenoses (50-69%). The benefit is less pronounced for women with moderate stenosis and they should be considered individually. In asymptomatic patients, surgery reduces the 5-year stroke risk from 11.8 to 6.4%. The indication for surgery in asymptomatic patients must be balanced against age, co-morbidity, and the quality of surgery at each centre. A low operative morbidity is a prerequisite. No comparable evidence exists for endovascular treatment, and it is recommended that patients eligible for stent treatment are included in ongoing randomised trials comparing stent treatment and endarterectomy.