Abstract
The clinical markers for carotid endarterectomy (CE) have traditionally been transient ischemic attack (TIA) or minor stroke. Whether CE should be restricted to this symptomatic category of carotid stenosis has become a public health issue, particularly in recent years when cost-effectiveness has become such a major consideration. With rare exceptions, all patients, whether they have had a TIA or nondisabling infarction, are asymptomatic at the time of CE. Therefore, how long after such an event a patient should be termed symptomatic is not a theoretical issue because, traditionally, once a TIA has occurred, the patient is classified as symptomatic no matter how much time has elapsed. CE is safer for truly asymptomatic patients with carotid stenosis because they are usually younger, have fewer associated risk factors, and the artery in these patients may be a better tissue for surgical repair. Whether asymptomatic patients with carotid stenosis should be treated only medically with risk factor reduction and antiplatelet agents or with CE as well has been addressed only partially. The US Veterans Administration Trial demonstrated a statistically significant reduction in the occurrence of combined end points of TIA, infarction and vascular death but not for stroke alone. The CASANOVA Trial was flawed and cannot be used. The Asymptomatic Carotid Atherosclerosis Study closed case acquisition at 1,662 patients in December 1993, and will provide definitive answers to this very important question.