The treatment of coronary and peripheral artery disease using stents has been one of the most revolutionary and most rapidly adopted medical interventions of our time. There have been significant developments in stents design, including assessment of different materials and surface treatments which have been driven by clinical needs within the cardiovascular stent field. This paper reviews the current state of the art for coronary stent materials and surface coatings, with an emphasis on new technologies that followed on from first generation bare metal and drug-eluting stents. Considering that current commercial devices have indeed high levels of safety and efficacy, there is an impressive array of technologies aimed at eliciting further improvements.
O’Brien B1, Zafar H2, Ibrahim A3, Zafar J4, Sharif F3,5,6,7.Show Affiliations
- Biomedical Engineering, School of Engineering & Informatics, National University of Ireland (NUI), Galway, Ireland.
- School of Physics, NUI, Galway, Room AO 205, Arts & Science Building, University Road, Galway, Ireland. [email protected]
- Department of Cardiology, University Hospital Galway, Galway, Ireland.
- Faculty of Engineering, Govt College University, Lahore, Pakistan.
- HRB Clinical Research Facility, Galway, Ireland.
- Regenerative Medicine Institute, NUI, Galway, Ireland.
- BioInnovate, Galway, Ireland.
This paper reviews the current state of the art for coronary stent materials and surface coatings, with an emphasis on new technologies that followed on from first-generation bare metal and drug-eluting stents. These developments have been driven mainly by the need to improve long term outcomes, including late stent thrombosis. Biodegradable drug-eluting coatings aim to address the long term effects of residual durable polymer after drug elution; the SYNERGY, BioMatrix, and Nobori stents are all promising devices in this category, with minimal polymer through the use of abluminal coatings. Textured stent surfaces have been used to attached drug directly, without polymer; the Yukon Choice and BioFreedom stents have some promising data in this category, while a hydroxyapatite textured surface has had less success. The use of drug-filled reservoirs looked promising initially but the NEVO device has experienced both technical and commercial set-backs. However this approach may eventually make it to market if trials with the Drug-Filled Stent prove to be successful. Non-pharmacological coatings such as silicon carbide, carbon, and titanium-nitride-oxide are also proving to have potential to provide better performance than BMS, without some of the longer term issues associated with DES. In terms of biological coatings, the Genous stent which promotes attachment of endothelial progenitor cells has made good progress while gene-eluting stents still have some practical challenges to overcome. Perhaps the most advancement has been in the field of biodegradable stents. The BVS PLLA device is now seeing increasing clinical use in many complex indications while magnesium stents continue to make steady advancements.Go To Ann Biomed Eng