Carotid endarterectomy in asymptomatic carotid stenosis: a decision analysis.

Objectives: To present a model of decision analysis that allows assessing the trade-off between the short-term risks of performing a carotid endarterectomy and the rate of preventable future events.

Methods: We used data from a systematic review to define values for a base case and perform a sensitivity analysis. The primary endpoint was a comparison of the fatal and disabling stroke-free survival during a 5-year period in a cohort of hypothetical patients who presented asymptomatic severe carotid stenosis and were treated with either immediate prophylactic carotid endarterectomy or medical treatment alone.

Results: The difference in estimated fatal and disabling stroke-free survival favoring endarterectomy in patients with asymptomatic severe carotid stenosis is less than 4 days over the course of 5 years. One-way sensitivity analysis demonstrated that if the perioperative rate of death or disabling stroke is greater than 2.1%, then medical treatment is better. A non-surgical strategy is also better if the risk of fatal and disabling stroke with medical treatment is less than 1.09% per year, or if the rate of fatal and disabling stroke beyond 30 days following endarterectomy is greater than 0.51% per year.

Conclusions: In this model, immediate prophylactic carotid endarterectomy seems to offer a minimum net benefit in terms of fatal or disabling stroke-free survival over a 5-year period, when compared to medical treatment alone.