Design and Validation of a Novel Ferromagnetic Bare Metal Stent Capable of Capturing and Retaining Endothelial Cells

Autor: Martin Klabusay, Ota Hlinomaz, Brandon J. Tefft, Dan Dragomir-Daescu, Susheil Uthamaraj, Gurpreet S. Sandhu
Rok vydání: 2014
Předmět:
Zdroj: Annals of Biomedical Engineering. 42:2416-2424
ISSN: 1573-9686
0090-6964
Popis: Rapid healing of vascular stents is important for avoiding complications associated with stent thrombosis, restenosis, and bleeding related to antiplatelet drugs. Magnetic forces can be used to capture iron-labeled endothelial cells immediately following stent implantation, thereby promoting healing. This strategy requires the development of a magnetic stent that is biocompatible and functional. We designed a stent from the weakly ferromagnetic 2205 stainless steel using finite element analysis. The final design exhibited a principal strain below the fracture limit of 30% during crimping and expansion. Ten stents were fabricated and validated experimentally for fracture resistance. Another 10 stents magnetized with a neodymium magnet showed a magnetic field in the range of 100-750 mG. The retained magnetism was sufficiently strong to capture magnetically-labeled endothelial cells on the stent surfaces during in vitro studies. Magnetically-labeled endothelial cell capture was also verified in vivo after 7 days following coronary implantation in 4 pigs using histological analysis. Images of the stented blood vessels showed uniform endothelium formation on the stent surfaces. In conclusion, we have designed a ferromagnetic bare metal stent from 2205 stainless steel that is functional, biocompatible, and able to capture and retain magnetically-labeled endothelial cells in order to promote rapid stent healing.
Databáze: OpenAIRE