Carotid artery stenosis is a narrowing or constriction of the inner surface of the carotid artery and is serious because it can cause a stroke. 30% of the cause of stroke is from this disease and occurrence of this disease is rapidly increasing in Korea because of the lifestyle changes. The narrowing of the carotid arteries is most commonly related to atherosclerosis, and it is closely related with adult diseases, such as hypertension, hyperlipidemia, and diabetes. Not all patients have symptoms; carotid artery disease may be asymptomatic or symptomatic. It is considered that 2–3% of asymptomatic carotid stenosis patients have the risk of stroke, and 10–17% of symptomatic patients have the risk of stroke.

Carotid steonsis is conventionally treated by carotid endarterectomy (CEA) as a preventive treatment of stroke, and patients with and without neurological symptoms are selectively treated with this treatment method. Carotid-artery stenting (CAS) was developed as an option for patients who are high risk for CEA or patients who has high risk because of carotid lesions located at or above the level of the second cervical vertebra. Clinical guideline in Korea recommends (Level of Evidence 1b, Classification of Recommendation A) that CAS indicated as an alternative to CEA for symptomatic patients who have more than 50% stenosis and the anticipated rate of stroke or mortality is less than 6% (Clinical Research Center For Stroke, 2011).

Therefore, this study evaluated the clinical effectiveness and cost-effectiveness in the target patients with symptomatic carotid artery stenosis (more than 50% stenosis) who can undergo CAS as an alternative to CEA for carotid artery stenosis. The four detailed topics to achieve the object of this study are the following: first, the utilization trends (2008-2012) of the treatments (CEA and CAS) in patients with symptomatic carotid artery stenosis in Korea by using national health insurance claims database provided HIRA; second, the comparative effectiveness of the CEA and CAS based on systematic reviews in patients with symptomatic carotid artery stenosis; third, the comparative effectiveness of the CEA and CAS based on retrospective chart review of patients with symptomatic carotid artery stenosis (>50%) collected from five hospitals in Korea (2008-2011); fourth, the cost-utility analysis of CEA versus CAS in patients with symptomatic carotid artery stenosis.