Effect of ionizing radiation on the stability and performance of the TAXUS Express2 paclitaxel-eluting stent.

Cardiovascular radiation medicine

PubMedID: 15721849

Dilcher C, Chan R, Hellinga D, Seabron R, Pakala R, Kuchulakanti PK, Richard R, Chan K, Zhong S, Barry JJ, Waksman R. Effect of ionizing radiation on the stability and performance of the TAXUS Express2 paclitaxel-eluting stent. Cardiovasc Radiat Med. 2005;5(3):136-41.
BACKGROUND
The advent of drug-eluting stents has provided the interventional cardiologist an effective new tool in treating coronary restenosis. There remains, however, a small group of patients that still require intervention following drug-eluting stent therapy. Currently, intravascular brachytherapy (IVBT) is approved for use in the treatment of in-stent restenosis (ISR). This study investigated the effect of gamma and beta radiation doses typically used in IVBT on the performance of the TAXUS Express(2) paclitaxel-eluting stent.

METHODS AND RESULTS
It was determined that there were no statistically significant changes to in vitro paclitaxel release from stent exposed to radiation compared to controls subjected to the same conditions except for the radiation exposure. The molecular weight of the Translute polymer carrier matrix and the level of paclitaxel degradants were not changed following exposure to radiation doses up to twice what is typically used in IVBT. Beta and gamma radiation doses typically used in IVBT had no significant effect on the Translute polymer carrier, paclitaxel degradation, or paclitaxel release in this in vitro model.

CONCLUSION
The data are encouraging and support further evaluation of the use of IVBT in the treatment of ISR in the presence of drug-eluting stents.