Restenosis of the CYPHER-Select, TAXUS-Express, and Polyzene-F nanocoated cobalt-chromium stents in the minipig coronary artery model.
OBJECTIVE
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.


METHODS
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.


RESULTS
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 microm) versus the TAXUS (74.864 +/- 66.03 microm) and versus the CCPS (63.542 +/- 39.57 microm). 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.


CONCLUSIONS
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.
Radeleff
Boris
B
Department of Radiology, University Heidelberg, INF 110, 69120, Heidelberg, Germany. Boris.radeleff@med.uni-heidelberg.de
Thierjung
Heidi
H
Stampfl
Ulrike
U
Stampfl
Sibylle
S
Lopez-Benitez
Ruben
R
Sommer
Christof
C
Berger
Irina
I
Richter
Goetz M
GM
D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation / Q000379:methods; D000818:Animals; D001707:Biopsy, Needle; D001807:Blood Vessel Prosthesis; D002857:Chromium / Q000494:pharmacology; D020099:Coated Materials, Biocompatible; D003035:Cobalt / Q000494:pharmacology; D003327:Coronary Disease / Q000473:pathology / Q000628:therapy*; D023903:Coronary Restenosis / Q000473:pathology*; D004195:Disease Models, Animal; D054855:Drug-Eluting Stents; D005260:Female; D007150:Immunohistochemistry; D053761:Nanocomposites; D011108:Polymers; D011336:Probability; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011897:Random Allocation; D012680:Sensitivity and Specificity; D020123:Sirolimus / Q000627:therapeutic use; D013552:Swine; D013556:Swine, Miniature; D016559:Tacrolimus
D020099:Coated Materials, Biocompatible; D011108:Polymers; D002857:Chromium; D003035:Cobalt; D020123:Sirolimus; D016559:Tacrolimus