Predictors of carotid artery in-stent restenosis

Abstract

Carotid angioplasty and stenting (CAS) is increasingly being used as a treatment alternative to endarterectomy (CEA), especially in patients aged <70 years with significant carotid artery stenosis. However, an in-stent restenosis (ISR) might endangering the long-term efficacy of CAS. The aim of this article was to review the current literature regarding incidence and clinical significance as well as predictors of in-stent restenosis. We conducted a systematic review of the literature to identify all studies on the abovementioned factors. 3 randomized-controlled trials comparing CAS and CEA and 13 single centre studies fulfilled our inclusion criteria. The occurrence of ISR after CAS ranged from 2.7 to 33% and was detected within the first year in most of the studies. The clinical impact as well as the therapeutic consequence of ISR remains unclear, but many baseline characteristics (age, prior CEA or radiation), procedural (insufficient stent deployment, stent dimensions, inflammatory marker) and follow-up factors (reduced HDL, diabetes mellitus) could be found to identify patients at special risk for ISR. A wide heterogeneity related to the definition and their corresponding ultrasound criteria for ISR was observed. A close follow-up is suggested especially in those patients with predictors of an ISR. The wide range of ISR ultrasound definitions urges the need for an implementation of generally valid criteria in ISR diagnosis. Against the background of the unknown clinical significance of ISR and a lacking established treatment modality these findings should be taken into account when offering CAS as a treatment alternative to CEA.