Natural history of symptomatic and asymptomatic carotid artery occlusion contralateral to carotid endarterectomy: a prospective study.

The natural history of carotid occlusion (CO) has generally been analyzed in the presence of a contralateral patent but diseased internal carotid artery (ICA). Few previous studies have focused on the fate of CO contralateral to the side of a prior carotid endarterectomy (CEA). The aim of this study was to analyze the mortality rate and the incidence of cerebrovascular events in the hemisphere ipsilateral to CO (HICO) in patients who had undergone contralateral CEA. The 30-day and long-term outcomes of 153 consecutive patients who had CEA for severe symptomatic and asymptomatic ICA lesions contralateral to a symptomatic or asymptomatic CO over a 15-year period were considered. The endpoints of the study were mortality and neurological events in the HICO. Overall, the 30-day mortality and stroke rates were 0.6% (1/153) and 1.9% (3/153), respectively; the only death was stroke-related and the stroke was ipsilateral to the operated side. The other 2 strokes were ipsilateral to a symptomatic CO. The follow-up was completed for all patients (mean, 7.7 years; range, 1-172 months). Overall, there were 4 late strokes (2.6%), one of them lacunar in a patient with a symptomatic CO, whereas the other 3 were atheroembolic and ipsilateral to the operated ICA. The risk of late stroke in the HICO at 5 and 12 years was 2%. Overall, there were 19 late deaths, none of them stroke-related. CO, with or without symptoms, contralateral to CEA could be considered a locally benign condition in the long term.