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.