Disease progression in the contralateral carotid artery after endarterectomy.

Our objectives were to establish the incidence and progression of stenotic lesions in the contralateral carotid artery (CCA) after endarterectomy, to identify subpopulations of patients at risk of contralateral disease progression, and to evaluate the efficacy of duplex scanning surveillance at detecting these lesions. We performed a prospective study on 180 patients in whom the CCA to the operated artery was healthy or showed <70% stenosis. All patients had completed a clinical and hemodynamic follow-up program, including duplex scanning of both carotids, with sessions 3 and 6 months after surgery and then every semester until 2 years. Thereafter, examinations were scheduled according to the severity of stenosis. Mean follow-up time was 26.2 months (range 1.6-67.6). Disease progression was observed in 26 lesions (15%), nine of which (5.5%) progressed to severe stenosis (SS). Kaplan-Meier event-free rates of any disease progression were 89%, 88%, 82%, and 79% for 1, 2, 3, and 4 years, respectively. Event-free rates of progression to SS were 98%, 96%, 93%, and 90.6%, respectively, for 1, 2, 3, and 4 years. The risk of progression to SS was five times higher for stenoses that were moderate at the start of the study (p = 0.025). Severe contralateral stenoses were more common and appeared later during follow-up than ipsilateral restenoses. Progression of contralateral stenotic lesions is not uncommon and is essentially related to the presence of a moderate lesion at the start of follow-up. Indeed, moderate stenosis is a risk factor for progression to SS, which appears later and more frequently than ipsilateral restenosis. It therefore seems that patients with a moderate contralateral lesion would benefit from long-term duplex ultrasound surveillance.