Factors affecting long-term restenosis after carotid stenting for carotid atherosclerotic disease

The most significant factors leading to restenosis are yet to be described in the literature. The purpose of our study was to identify the incidence of restenosis in our patients with carotid artery stenting (CAS) for carotid atherosclerotic disease and to identify risk factors that are significantly responsible or related to the restenosis.

In this retrospective analysis of patients who underwent CAS for atherosclerotic disease between years 2002 and 2006, we studied various demographic, clinical, and medical factors, plaque characteristics, and technical aspects of CAS. All patients were followed up with carotid Doppler ultrasound at baseline (after 2 to 4 weeks of CAS) and then with Doppler ultrasound and clinically for various intervals of time. The restenosis was classified based on carotid Doppler ultrasound results. Clinically, restenosis was classified as symptomatic or asymptomatic. Pearson correlation coefficient was used to assess the statistical correlation of the different factors with the incidence of restenosis.

We had a total of 105 patients, with a total of 204.6 patient-year follow-up (mean, 1.95 years; range, 0-7.3 years). The overall incidence of restenosis was 26.7 % (n = 28): mild, 7.6 % (n = 8); moderate, 10.5 % (asymptomatic, 11; symptomatic, 0); and severe, 8.6 % (asymptomatic, 5; symptomatic, 4). Overall, 14.3 % (n = 4) patients with restenosis were symptomatic and 7.1 % (n = 2) underwent retreatment. Post-stenting residual stenosis greater than either 30 % (p = 0.016) or 50 % (p = 0.05) were significant for long-term restenosis. Plaques longer than 20 mm were significantly related to restenosis (p < 0.001).

The most important factor to explain restenosis was the immediate post-CAS residual stenosis and length of the plaque.