Annals of Biomedical Engineering

, Volume 42, Issue 12, pp 2416–2424 | Cite as

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

  • Susheil Uthamaraj
  • Brandon J. Tefft
  • Martin Klabusay
  • Ota Hlinomaz
  • Gurpreet S. Sandhu
  • Dan Dragomir-DaescuEmail author


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.


Magnetic stent Stent healing Endothelialization Finite element analysis Restenosis Thrombosis 



The authors thank Tyra Witt, Cheri Mueske, Brant Newman and Dr. Peter J. Psaltis, MBBS, Ph.D. for their valuable contributions to this study. The authors also thank Drs. Maria Kempe, Ph.D., Shu Q. Liu, Ph.D., Adriele Prina-Mello, Ph.D., and Tré R. Welch, Ph.D. for their suggestions in writing this manuscript. This study was financially supported by European Regional Development Fund—FNUSA-ICRC (No. CZ.1.05/1.100/02.0123), American Heart Association Scientist Development Grant (AHA #06-35185N) and The Grainger Innovation Fund—The Grainger Foundation.


The authors have no relevant disclosures.


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Copyright information

© Biomedical Engineering Society 2014

Authors and Affiliations

  • Susheil Uthamaraj
    • 1
  • Brandon J. Tefft
    • 2
  • Martin Klabusay
    • 3
  • Ota Hlinomaz
    • 4
  • Gurpreet S. Sandhu
    • 2
    • 5
  • Dan Dragomir-Daescu
    • 1
    • 5
    Email author
  1. 1.Division of EngineeringMayo ClinicRochesterUSA
  2. 2.Division of Cardiovascular DiseasesMayo ClinicRochesterUSA
  3. 3.Integrated Center of Cellular Therapy and Regenerative Medicine, ICRCSt. Anne’s University HospitalBrnoCzech Republic
  4. 4.Department of Cardioangiology, ICRCSt. Anne’s University HospitalBrnoCzech Republic
  5. 5.Mayo Clinic College of MedicineRochesterUSA

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