Background:

Carotid artery stenosis is an important cause for stroke. Carotid endarterectomy (CEA) reduces the risk of stroke in patients with symptomatic carotid stenosis and to some extent in patients with asymptomatic carotid stenosis. More than 20 years ago, carotid artery stenting (CAS) emerged as an endovascular treatment alternative to CEA.

Objective and Methods:

This review summarises the available evidence from randomised clinical trials in patients with symptomatic as well as in patients with asymptomatic carotid stenosis.

Results:

CAS is associated with a higher risk of death or any stroke between randomisation and 30 days after treatment than CEA (odds ratio (OR) = 1.74, 95% CI 1.3 to 2.33, p < 0.0001). In a pre-defined subgroup analysis, the OR for stroke or death within 30 days after treatment was 1.11 (95% CI 0.74 to 1.64) in patients <70 years old and 2.23 (95% CI 1.61 to 3.08) in patients ≥70 years old, resulting in a significant interaction between patient age and treatment modality (interaction p = 0.007). The combination of death or any stroke up to 30 days after treatment or ipsilateral stroke during follow-up also favoured CEA (OR = 1.51, 95% CI 1.24 to 1.85, p < 0.0001).

In asymptomatic patients, there is a non-significant increase in death or stroke occurring within 30 days of treatment with CAS compared to CEA (OR = 1.72, 95% CI 1.00 to 2.97, p = 0.05). The risk of peri-procedural death or stroke or ipsilateral stroke during follow-up did not differ significantly between treatments (OR = 1.27, 95% CI 0.87 to 1.84, p = 0.22).

Discussion and Conclusion:

In symptomatic patients, randomised evidence has consistently shown CAS to be associated with a higher risk of stroke or death within 30 days of treatment than CEA. This extra risk is mostly attributed to an increase in strokes occurring on the day of the procedure in patients ≥70 years. In asymptomatic patients, there may be a small increase in the risk of stroke or death within 30 days of treatment with CAS compared to CEA, but the currently available evidence is insufficient and further data from ongoing randomised trials are needed.