A review of current devices and a look at new technology: drug-eluting stents

Abstract

Drug-eluting stents (DES) have become the standard of care for the treatment of coronary artery disease. However, late stent thrombosis has emerged as a major concern, especially in ‘off-label’ use. Pathologic studies of patients dying from late DES thrombosis demonstrate delayed arterial healing, characterized by persistent fibrin deposition and poor endothelialization as the primary substrate. Therefore, next-generation DES are being developed to increase the safety and biocompatibility by optimizing the three major components of DES: the stent platform, the polymer and the drug. Stents with thinner struts are endothelialized rapidly and cause less vessel-wall injury. Non-erodable polymers applied thinly and without defect or cracking cause less inflammation and will result in better long-term safety. Furthermore, use of biodegradable polymers, which fully degrade and leave a bare metal stent, will result in less inflammation. The choice of drug, dose and release kinetics should also be optimized. In addition to the improvement of DES components, new approaches, such as polymer-free drug delivery, prohealing approach and fully biodegradable stents, are emerging. Importantly, these technologies focus not only on efficacy but also on safety. The next-generation DES will probably be safer, with goals of improving endothelialization and more rapid arterial healing compared with first- and second-generation DES.

Keywords::

• biodegradable polymer
• drug-eluting stent
• new technology
• stent design

Financial & competing interests disclosure

Renu Virmani receives company-sponsored research support from: 3F Theraputics; Abbott Vascular; Amaranth Medical, Inc.; Apnex Medical; Ardian, Inc.; Atrium Medical Corporation; CardioDex, LTD; CardioKinetix, Inc.; CorAssist Cardiovascular LTD; Cordis Corporation; Devax, Inc.; ev3; Gardia Medical Ltd; GlaxoSmithKline; HemCon; Lutonix, Inc.; Medtronic Vascular; Meril Life Sciences Pvt Ltd; Microvention, Inc.; Novartis Pharmaceuticals Corporation; NovoStent Corporation; Oregon Medical Laser Center; Prescient Medical, Inc.; Relisys Medical Devices Limited; Vascular Therapies, LLC; and Xtent, Inc.

R Virmani is also a Consultant for: Medtronic AVE; Abbott Vascular; WL Gore; Volcano Therapeutics, Inc.; Prescient Medical; CardioMind, Inc.; Direct Flow; and Atrium Medical Corporation.

No writing assistance was utilized in the production of this manuscript.