4. Current status of operative treatment for asymptomatic carotid stenosis

To determine the natural history of asymptomatic carotid stenosis and the effect of prophylactic carotid surgery on neurologic morbidity and mortality.

A prospective, randomized, cooperative study, with a mean follow-up of 47.9 months.

Ten Veterans Administration hospitals across the United States.

The study comprised 436 patients who were divided into two groups: group 1, patients with symptomatic unilateral carotid disease, who were treated with carotid endarterectomy, and had contralateral asymptomatic stenosis; group 2, patients with significant asymptomatic carotid disease. Carotid stenosis was confirmed by arteriography, which demonstrated at least 50% stenosis, measured by comparing the least transverse diameter of the stenosis on lateral arteriography.

Ocular plethysmography, duplex scanning and arteriography; carotid endarterectomy and acetylsalicylic acid or acetylsalicylic acid alone.

The 436 patients were randomized between nonoperative (medical) (233) and operative (surgical) (211 procedures on 203 patients) groups. In the surgical group, the 30-day mortality was 1.9% and the permanent neurologic morbidity was 2.4%, for a combined stroke and death rate of 4.3%. The incidence of neurologic events was 8% in the surgical group compared with 20.6% in the medical group, for an absolute reduction in risk of 12.6% (p < 0.001).

Carotid endarterectomy, combined with optional medical management, can reduce the incidence of ipsilateral neurologic events in high-risk men with arteriographically confirmed asymptomatic carotid stenosis.