The Probability of Restenosis, Contralateral Disease Progression, and Late Neurologic Events following Carotid Endarterectomy: A Long-Term Follow-Up Study

Abstract

Background: Most studies that have reported on the progression of ipsilateral and/or contralateral internal carotid artery (ICA) stenosis are restricted to a few years. Methods: Based on a single-center carotid endarterectomy (CEA) registry, we sought all patients with CEA for symptomatic high-grade ICA stenosis between 1970 and 2002. 361 CEA patients (mean age 66 years, 73% male) with annual carotid ultrasound and clinical follow-up were identified. Kaplan-Meier analysis was used to estimate the occurrence of (i) progressive ICA stenosis or restenosis of either the operated or contralateral side, and (ii) cerebrovascular events over time of either the operated or contralateral side. Results: Progressive ICA disease was more likely on the contralateral than on the ipsilateral ICA (hazard ratio 2.71; CI 1.8–4.1, p < 0.001). After 5 years, the probability for progressive ICA disease was 5.2% for the ipsilateral versus 15.8% for the contralateral ICA. After 15 years, the likelihood was 37% for both sides. In the presence of progressive restenosis of the ipsilateral ICA, the 20-year probability of further ischemic cerebrovascular events was 50% compared to 18% in patients without ICA disease progression. For the contralateral ICA, the probability of further ischemic events was 24.5% in patients with ICA disease progression compared to 9.6% without ICA disease progression (15 years). Conclusion: 15 years after CEA, one third of the patients can be expected to develop progressive ICA disease. While ICA disease progression seems to be more prominent on the contralateral ICA within the first years, this difference fades out after 15 years. One out of 2 patients with ipsilateral ICA disease progression can be expected to have a recurrent cerebral ischemic event within 15 years. It remains to be determined whether consequent application of high-dose statins, optimal blood pressure management and antithrombotic therapy can reduce this rate.