LONG-TERM PROGNOSIS AND THE EFFECT OF CAROTID ENDARTERECTOMY IN PATIENTS WITH RECURRENT IPSILATERAL ISCHEMIC EVENTS

Background and purpose: The present study examines how the prognosis o f patients who present with an ischemic event (TIA or nondisabling str oke) referable to a 70 to 99% carotid artery stenosis is modified by t he pattern of their ischemic history. We also examined the benefits of performing carotid endarterectomy on the recently symptomatic artery. Methods: A total of 608 patients was divided into two groups. The rec ent group (N = 444) consisted of patients who became newly symptomatic within the previous 6 months of their presenting event. Prior to this , they were asymptomatic. The recurrent group (N = 164) consisted of p atients who had one or more ischemic events within the previous 6 mont hs of their presenting event, as well as one or more within the previo us 7 to 12 months. All events were ipsilateral to the presenting event . Results: Kaplan-Meier risk estimates of ipsilateral stroke at 2 year s for medically treated patients were 18.6 +/- 3.3% in the recent grou p and 41.2 +/- 6.9% in the recurrent group (p = 0.0002, logrank test). For patients who underwent carotid endarterectomy, the risks were 7.8 +/- 2.0% and 10.8 +/- 3.4% (p = 0.36, logrank test). Multivariate ana lyses did not identify any baseline patient characteristics as confoun ders nor any statistical interactions. Conclusions: There is a need fo r urgency in considering carotid endarterectomy for patients with 70 t o 99% carotid artery stenosis who have had recurrent ipsilateral ische mic events extending back more than 6 months. These patients are at mo re than twice the risk of stroke as those who are newly symptomatic.