Recent advances in drug eluting stents

Abstract

One of the most common medical interventions to reopen an occluded vessel is the implantation of a coronary stent. While this method of treatment is effective initially, restenosis, or the re-narrowing of the artery frequently occurs largely due to neointimal hyperplasia of smooth muscle cells. Drug eluting stents were developed in order to provide local, site-specific, controlled release of drugs that can inhibit neointima formation. By implementing a controlled release delivery system it may be possible to control the time release of the pharmacological factors and thus be able to bypass some of the critical events associated with stent hyperplasia and prevent the need for subsequent intervention. However, since the advent of first-generation drug eluting stents, long-term adverse effects have raised concerns regarding their safety. These limitations in safety and efficacy have triggered considerable research in developing biodegradable stents and more potent drug delivery systems. In this review, we shed light on the current state-of-the-art in drug eluting stents, problems related to them and highlight some of the ongoing research in this area.

Drug Eluting Stents Coated With Rapamycin Crystals for the Prevention of Restenosis and Biofilm Formation

“…The use of poly vinyl pyrrolidone as a polymer offers the possibility to place hydrophilic drugs on the surfaces of hydrophobic stents and implants, building up a slow-release drug delivery system independent of the drug charge. This statement was well coincided with the literature review of Puranik et al 34 . The researchers cited the types and significant properties of polymer coated implants, biodegradable implants and drug-carrier stents.…”

Controlled Drug Release Systems: Mechanisms and Kinetics

“…In order to reduce restenosis of the artery due to hyperplasia reaction at the stented site, stents coated with polymeric layers containing antirestenotic drugs have been developed (Table 1.1). Research and development in this area is currently very active, aiming at the improved efficacy and safety through stent design and choice of polymer and drug [Khan et al, 2012;Puranik et al, 2013]. · Vaginal inserts.…”

Targeting AGGF1 (angiogenic factor with G patch and FHA domains 1) for Blocking Neointimal Formation After Vascular Injury

“…Incidence of restenosis has been reduced to 17% to 41% with use of bare‐metal stents and further reduced to 10% with the use of drug‐eluting stents 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17. However, drug‐eluting stents presented with an unexpected problem of an increased rate of in‐stent thrombosis (0.5–3.1%),4, 5, 6, 7, 18, 19 which causes a significantly high 6.3% rate of MI and death 18, 20, 21, 22. This led to a 20% reduction in the use of drug‐eluting stents 23.…”