Drug Eluting Stents in Adults with In-stent Restenosis: A Review of the Clinical Effectiveness, Safety and Guidelines

In-stent restenosis is re-narrowing of the stented segment of the blood vessel and occurs in 15 to 50% of patients after implantation of bare metal stents. It usually occurs three to 12 months after stent implantation. Although with the advent of drug eluting stents there has been a decrease in the incidence of in-stent restenosis, it still remains an issue, especially in patients with highly complex lesions. In-stent restenosis is not a benign condition and approximately 18% of patients with clinically significant in-stent restenosis present with acute coronary syndrome and 2% of these patients have ST- elevation myocardial infarction. There are several approaches to treat in-stent restenosis. These include balloon angioplasty (BA), vascular brachytherapy (VBT), and re-stenting with a bare metal stent or drug eluting stent. Drug eluting stents with various anti-proliferative drugs are available. However, choice of the optimal treatment strategy remains a challenge. The purpose of this review is to provide evidence on the clinical effectiveness and safety of drug eluting stents in adults with in-stent restenosis in comparison with other treatment options and to provide evidence-based guidelines on the use of drug eluting stents in adults with in-stent restenosis.