CardioVascular and Interventional Radiology

, Volume 31, Issue 5, pp 971–980 | Cite as

Restenosis of the CYPHER-Select, TAXUS-Express, and Polyzene-F Nanocoated Cobalt-Chromium Stents in the Minipig Coronary Artery Model

  • Boris RadeleffEmail author
  • Heidi Thierjung
  • Ulrike Stampfl
  • Sibylle Stampfl
  • Ruben Lopez-Benitez
  • Christof Sommer
  • Irina Berger
  • Goetz M. Richter
Laboratory Investigation



To date no direct experimental comparison between the CYPHER-Select and TAXUS-Express stents is available. Therefore, we investigated late in-stent stenosis, thrombogenicity, and inflammation, comparing the CYPHER-Select, TAXUS-Express, and custom-made cobalt chromium Polyzene-F nanocoated stents (CCPS) in the minipig coronary artery model.


The three stent types were implanted in the right coronary artery of 30 minipigs. The primary endpoint was in-stent stenosis assessed by quantitative angiography and microscopy. Secondary endpoints were inflammation and thrombogenicity evaluated by scores for inflammation and immunoreactivity (C-reactive protein and transforming growth factor beta). Follow-up was at 4 and 12 weeks.


Stent placement was successful in all animals; no thrombus deposition occurred. Quantitative angiography did not depict statistically significant differences between the three stent types after 4 and 12 weeks. Quantitative microscopy at 4 weeks showed a statistically significant thicker neointima (p = 0.0431) for the CYPHER (105.034 ± 62.52 μm) versus the TAXUS (74.864 ± 66.03 μm) and versus the CCPS (63.542 ± 39.57 μm). At 12 weeks there were no statistically significant differences. Inflammation scores at 4 weeks were significantly lower for the CCPS and CYPHER compared with the TAXUS stent (p = 0.0431). After 12 weeks statistical significance was only found for the CYPHER versus the TAXUS stent (p = 0.0431). The semiquantitative immunoreactivity scores for C-reactive protein and transforming growth factor beta showed no statistically significant differences between the three stent types after 4 and 12 weeks.


The CCPS provided effective control of late in-stent stenosis and thrombogenicity in this porcine model compared with the two drug-eluting stents. Its low inflammation score underscores its noninflammatory potential and might explain its equivalence to the two DES.


Drug-eluting stent Inflammation Polyzene-F Restenosis 



Funding sources. This study was sponsored in part by CeloNova BioSciences., Inc. Newnan, GA, USA.

Financial disclosures. U.S., R.L.-B, and G.M.R. have sponsored research agreements with CeloNova BioSciences, Inc., Newnan, GA, USA. G.M.R. has served as consultant to CeloNova BioSciences, Inc., Newnan, GA, USA.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Boris Radeleff
    • 1
    Email author
  • Heidi Thierjung
    • 1
  • Ulrike Stampfl
    • 1
  • Sibylle Stampfl
    • 1
  • Ruben Lopez-Benitez
    • 1
  • Christof Sommer
    • 1
  • Irina Berger
    • 2
  • Goetz M. Richter
    • 1
  1. 1.Department of RadiologyUniversity HeidelbergHeidelbergGermany
  2. 2.Department of PathologyUniversity HeidelbergHeidelbergGermany

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