Abstract 18021: A Time-course Study of Vasomotor Function After Implantation of Novel Paclitaxel-eluting Stent in Rabbit Iliac Arteries
Background: A growing body of clinical data has shown that the 1st-gen of paclitaxel-eluting stents (PES) implantation could lead to vasomotor dysfunction. Novel generation of PES (Labcoat) has much less drug in combination with abluminal biodegradable polymer coating that eventually leave a polymer-free BMS when drug is gone. In this study, we aimed to investigate the time-course changes of vasomotor function following implantation of a novel PES in rabbit iliac arteries.
Methods: BMS (Element, n=18) and Labcoat Element (Labcoat, n=18, about 10-fold less drug than the 1st-generation of TAXUS) were implanted at rabbit iliac arteries. Endothelial function at 5–10 mm distal to the stents was estimated by acetylcholine (Ach 10−5, 10−4 M/mL) and nitroglycerin (NTG, 200μg) infusion at 14d, 30d, and 90d (6 animals per time-point).
Results: Arteriographic minimal luminal diameter, as well as percent diameter stenosis, was not different between two groups (P>0.05). Decreased vasodilatory response (distal to the stent) for Labcoat group was found at earlier time points (14, 30d) when compared to BMS (Labcoat vs. BMS, Ach 10−5; −0.92±6.37% vs. 10.5 ±5.93%, Ach10−4; 0.81±3.96% vs. 10.72±6.30% at 14 days, p<0.01, respectively, Ach 10−5; −5.08±7.58% vs. 7.58±4.09%, Ach10−4; −4.61±4.30% vs. 10.17±3.03% at 30 days, p<0.01, respectively). However, at 90d, the vasomotor function response to Ach had no difference between two groups (Labcoat vs. BMS, Ach 10−5; 3.76±9.53% vs. 8.79±11.49%, Ach 10−4; 8.49±12.59% vs. 12.81±10.32%, p=NS, respectively). NTG-induced vasodilatation had no differences at all time point.
Conclusions: In vivo evaluation of the early and long-term safety after drug-eluting stent placement is important in clinical setting. Our results demonstrated that comparable endothelial function of BMS and Labcoat stented vessels was reached within three months post stent implantation, which may indicate completion of drug release and healing process.
- © 2010 by American Heart Association, Inc.