This review summarizes the available evidence and analyzes the current trends on treatments for carotid in-stent restenosis (ISR) after carotid artery stenting (CAS).Methods:
An update of a 2010 review of the literature (which included 20 articles) was conducted using PubMed and Embase. All studies published from inception until January 2016 reporting original data on ISR treatments were included. Treatment trends before and after 2005 were compared.Results:
We found 22 new articles reporting ISR treatments in 138 patients, of which two (case series) were published before 2005. With the inclusion of the 20 articles of the 2010 report (n = 96 patients), a total of 42 articles were included (23 case reports and 19 case series) reporting 239 interventions for ISR in 234 patients. Of these 42 studies, 14 (including 10 case series) were published before 2005. The interventions were percutaneous transluminal angioplasty (PTA) in 136, repeat CAS in 51, carotid endarterectomy in 39, carotid artery bypass in 10, or brachytherapy in 3. Compared with the articles published before 2005, PTA with regular balloon remains the most practiced treatment (26% before 2005, 40% after 2005). PTA with drug-coated balloons started after 2005. Carotid endarterectomy with stent removal was the second most reported treatment before 2005 but moved to the third place of reported interventions after 2005 owing to an increase in repeat CAS treatment. Of the treated patients, 140 were asymptomatic, 72 were symptomatic, and for 22 the symptomology was unclear. ISR treatment averaged 18 months after CAS, and the follow-up thereafter was 16 months. Treatment for recurrent ISR was performed in 48 of 239 treated arteries, mostly after PTA (n = 35) and repeat CAS (n = 8).Conclusions:
The available evidence for ISR treatment is still limited owing to methodologic heterogeneity; therefore, no recommendation on the optimal intervention can be provided. Although PTA is the common treatment for ISR, recurrent ISR seems to limit the durability, leading to recurrent interventions and cost implications. A uniform definition for ISR is needed with a standardized workup to compare the treatment options based on individual patient data analysis. Drug-eluting techniques are emerging and may become the preferred treatment option, but long-term follow-up is needed to evaluate their efficacy. Further study and understanding of the effect of drug-eluting technologies on the brain and neurologic function is warranted.