CardioVascular and Interventional Radiology

, Volume 34, Issue 1, pp 139–148 | Cite as

Self-Expanding Nitinol Renal Artery Stents: Comparison of Safety and Efficacy of Bare Versus Polyzene-F Nanocoated Stents in a Porcine Model

  • P. Kurz
  • U. Stampfl
  • P. Christoph
  • C. Henn
  • S. Satzl
  • B. Radeleff
  • I. Berger
  • G. M. RichterEmail author
Laboratory Investigation



To investigate the safety and efficacy of a Polyzene-F nanocoat on new low-profile self-expandable nitinol stents in minipig renal arteries.

Materials and Methods

Ten bare nitinol stents (BNS) and 10 stents coated with a 50 nm-thin Polyzene-F coating were randomly implanted into renal arteries of 10 minipigs (4- and 12-week follow-up, 5 animals/group). Thrombogenicity, on-stent surface endothelialization, vessel wall injury, late in-stent stenosis, and peristrut vessel wall inflammation were determined by quantitative angiography and postmortem histomorphometry.


In 6 of 10 BNS, >50% stenosis was found, but no stenosis was found in stents with a nanothin Polyzene-F coating. Histomorphometry showed a statistically significant (p < 0.05) different average maximum luminal loss of 55.16% ± 8.43% at 12 weeks in BNS versus 39.77% ± 7.41% in stents with a nanothin Polyzene-F coating. Stents with a nanothin Polyzene-F coating had a significantly (p < 0.05) lower inflammation score after 12 weeks, 1.31 ± 1.17 versus 2.17 ± 0.85 in BNS. The results for vessel wall injury (0.6 ± 0.58 for Polyzene-F-coated stents; 0.72 ± 0.98 for BNS) and re-endothelialization, (1.16 ± 0.43 and 1.23 ± 0.54, respectively) were not statistically significant at 12-week follow-up. No thrombus deposition was observed on the stents at either follow-up time point.


Nitinol stents with a nanothin Polyzene-F coating successfully decreased in-stent stenosis and vessel wall inflammation compared with BNS. Endothelialization and vessel wall injury were found to be equal. These studies warrant long-term pig studies (≥120 days) because 12 weeks may not be sufficient time for complete healing; thereafter, human studies may be warranted.


Interventional radiology In-stent stenosis Intimal hyperplasia Nitinol Renal artery stents Polyzene-F 


Conflict of interest

Authors U. S. and G. M. R received a research grant from CeloNova Biosciences, Newnan, GA, and G. M. R. has served as a consultant to CeloNova Biosciences, Newnan, GA.


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Copyright information

© Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2010

Authors and Affiliations

  • P. Kurz
    • 1
  • U. Stampfl
    • 2
  • P. Christoph
    • 2
  • C. Henn
    • 2
  • S. Satzl
    • 2
  • B. Radeleff
    • 2
  • I. Berger
    • 3
  • G. M. Richter
    • 1
    Email author
  1. 1.Clinics for Diagnostic and Interventional RadiologyKlinikum StuttgartStuttgartGermany
  2. 2.Department of Diagnostic and Interventional RadiologyUniversity of HeidelbergHeidelbergGermany
  3. 3.Institute of General PathologyHeidelbergGermany

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