Coronary Stent Materials and Coatings: A Technology and Performance Update

Significance Statement

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.

Coronary Stent Materials and Coatings: A Technology and Performance Update.Advances in Engineering

About the author

Barry O’Brien graduated from University of Limerick in 1987 with a B.Eng in Materials Engineering and then worked as a project engineer at BHP Laboratories in Limerick until 1995. During this time he worked on materials research projects investigating aerospace alloys, engineering ceramics and medical device materials. He also completed an M.Eng in 1991 on lightweight alloys for satellite structures. Barry joined Boston Scientific in 1996, working in R&D on projects to develop materials and processes for a range of self-expanding devices and balloon-expanding stents. Subsequently he was Technical Team Leader on a number of medical device technology projects covering topics such as iridium oxide stent coatings, alternative stent materials and novel drug delivery concepts. Barry returned to university, completing a PhD in 2009, in the field of MRI-compatible implant materials. He has since worked as Principal Investigator and Project Manager on a number of medical device projects relating to biodegradable magnesium implants and peripheral vascular stents. Currently he is NUI Galway’s project manager on an FP7 project that is developing a tissue-engineered tracheobronchial stent.

About the author

Haroon Zafar graduated with a B.Sc. in Electrical Engineering from University of Engineering and Technology, Lahore, Pakistan in 2007. He was awarded with the Erasmus Mundus Scholarship from European Commission to pursue his double degree in M.Sc. in Photonics. He received his first M.Sc. from University of St Andrews and Heriot Watt University, UK and received a second M.Sc. Engineering degree from Ghent University and Vrije Universiteit Brussel, Belgium in 2011. He was awarded with a Hardiman Research fellowship from National University of Ireland, Galway in 2011 to pursue his PhD in the field of BioPhotonics. His research focuses on the development and applications of optical imaging techniques for microcirculation imaging and cardiovascular imaging. He has over 30 high impact peer-reviewed publications to his credit and presented his work at several renowned international platforms. He was the founding president of the National University of Ireland, Galway and University of Limerick, SPIE Chapter. Currently he is programme manager of Cardiovascular Research Center at National University of Ireland, Galway.

About the author

Junaid Zafar has done his F.Sc. pre-Engineering from GC University, Lahore and B.Sc. in Electrical Engineering from University of Engineering & Technology, Lahore in 2005. He has been conferred upon the “Roll of Honor” from Pakistan Atomic Energy Commission in 2000. He completed his PhD in 2009 from the University of Manchester, UK. He served as Dual Degree Programme Coordinator, CIIT- Lahore- Lancaster University, UK. He has the credit of being declared as the “Outstanding HEC Young Research Scholar- 2012” in 2015. He has authored over 40 journal and conference publications. Currently, he is head of Electrical Engineering department at the GC University, Lahore and visiting lecturer at the University of Manchester.

About the author

Faisal Sharif is a consultant Interventional Cardiologist for Galway University Hospitals. His research focuses on medical devices for cardiovascular medicine, translational research on vascular biology and myocardial regeneration and developing novel solutions for unmet clinical needs for cardiovascular medicine. He is a Clinical Director and Advisory Board member for BioInnovate Ireland and Director of Cardiovascular Research Center, National University of Ireland, Galway. He has been inducted as a Fellow to the Royal College of Physicians Ireland (FRCPI), the European Society of Cardiology (FESC), the American College of Cardiology (FACC). He is the Associate Director for Clinical Research facility Galway for cardiovascular trials. He also serves as a board and faculty member for the Resistant Hypertension Course hosted by EuroPCR, the First Centre of Excellence (CoE) for renal artery denervation training in United Kingdom and Ireland. His key area of interest is translational medicine focusing on cardiovascular clinical trials for medical devices and basic science outputs. He has authored over 50 journal and conference publications.

Journal Reference

Ann Biomed Eng. 2016 Feb;44(2):523-35.

O’Brien B1, Zafar H2, Ibrahim A3, Zafar J4, Sharif F3,5,6,7.

Show Affiliations
  1. Biomedical Engineering, School of Engineering & Informatics, National University of Ireland (NUI), Galway, Ireland.
  2. School of Physics, NUI, Galway, Room AO 205, Arts & Science Building, University Road, Galway, Ireland. [email protected]
  3. Department of Cardiology, University Hospital Galway, Galway, Ireland.
  4. Faculty of Engineering, Govt College University, Lahore, Pakistan.
  5. HRB Clinical Research Facility, Galway, Ireland.
  6. Regenerative Medicine Institute, NUI, Galway, Ireland.
  7. BioInnovate, Galway, Ireland. 

Abstract

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

 

Check Also

Experimental investigation on the performance of a double-cylinder flow-induced vibration energy converter - Advances in Engineering

Performance of a double-cylinder flow-induced vibration energy converter