A system for impedance characterization of coronary stents

Stents are used to re-open and maintain flow in diseased coronary arteries in patients suffering from coronary heart disease. Drug-eluting stents are now the preferred choice of stent but their performance is still limited by delayed healing of the important endothelial cell layer that lines the artery wall (Capodanno et al, 2011). It is very important that the endothelial cells that are damaged following the implantation of the stent are regenerated. Much research has been carried out to monitor endothelialisation of the stent-tissue interface using invasive methods, but such methods are commonly only suitable for in vitro studies (Prasad et al, 2005), meaning they cannot be practically used clinically and can only provide information at a limited number of time points. The technique of impedance spectroscopy may allow the non-invasive measurement of endothelial cell growth on coronary stents. This project therefore sought to measure the in vitro impedance of a range of coronary stents. Impedance values were recorded from stainless steel wires, bare metal and drug-eluting stents in an in vitro experimental set up, where the stent itself acted as an electrode. The effects of temperature, magnetic agitation, medium, time and various different stent types on impedance were evaluated. It was found that each of the variables examined had an effect on the system impedance. The highest impedance was observed with the Cypher drug-eluting stent group, followed by a novel polypyrrole coated stent, whilst the bare metal stents displayed relatively low impedance levels. In most stent materials examined, the impedance characteristics varied with time. These findings provide the basis for future investigation of the non-invasive measurement of endothelial cell growth on coronary stents.

Name dc:type.qualificationname

msc

Level dc:type.qualificationlevel

masters-pg

Grantor dc:publisher.institution

University of Strathclyde

Year dc:date.issued

2015

Author dc:creator

• Gopinath, Divya

DOI

10.48730/et6b-gh64

Identifier

T14210

Author Identifier

201456687

OAI identifier oai:identifier

oai:strathclyde:p8418n313