Prevention of Carotid Artery Restenosis After Sirolimus-Coated Stent Implantation in Pigs

Abstract

Background and Purpose-To test the feasibility of self-expanding drug-coated nitinol stents for prevention of restenosis in an animal model. Stent implantation in the carotid artery (CA) has been shown to be feasible for treatment of CA stenosis. Even though the restenosis rate in CA is reported to be lower than in the coronary and peripheral arteries, problems may arise with increasing numbers of treated patients and lengthier follow-up. Methods-After predilatation with 8-mm balloons, 8 Goettinger minipigs were randomly selected to receive a sirolimus-eluting self-expanding nitinol stent (7 mm/80 mm) as well as the same stent without sirolimus/polymer coating in the right or left CA. Aspirin was given starting 3 days before the intervention and administered for an additional 4 weeks. Clopidogrel was administered for 10 days. Results-After 6 weeks, 2 subacute occlusions were observed in both groups. In the remaining vessels, the neointima was significantly reduced by sirolimus/polymer-coated stents (5.9Ϯ2.5 versus 0.7Ϯ1.0 mm 2 ). Conclusions-Sirolimus self-expanding nitinol stents may be an effective tool in reducing neointimal formation in CA.(Stroke. 2006;37:492-494.)

Histological analysis of cobalt–chromium stents with and without Camouflage® polymer coating: experimental porcine carotid artery model

“…In addition, they identified a high incidence of thrombosis in both groups, a fact that was correlated with inadequate platelet inhibition after the intervention. 31 In our study, we did not observe any acute or subacute thrombosis, which suggests that, in this animal model, the fact that no antiplatelet drug was used did not seem to be associated with thrombosis. In experimental studies, several drug treatments with and without platelet anti-binders have been used, with equally controversial results.…”

“…In this sense, the animal models Co-Cr stents in porcine carotid arteries that involve double lesions (balloon catheter + stent), although biologically interesting as they simulate many real conditions in clinical practice, offer a very broad variability of intimal response and are not recommended. 30 Tepe et al 31 used intravascular ultrasound to evaluate intimal thickening after the implantation of sirolimus-coated, self-expandable stents in carotid arteries of pigs. They found an almost total absence of neointima in the group that received pharmacological stents.…”

Delivery and release of nitinol stent in carotid artery and their interactions: A finite element analysis

“…3c1 and c2). These areas may induce irregular blood flow patterns to favor the thrombosis creation, or adversely influence the drug effects of future drug-eluting carotid stents (Tepe et al, 2006).…”

Sirolimus-Eluting Biodegradable Poly-l-Lactide Stent for Peripheral Vascular Application: A Preliminary Study in Porcine Carotid Arteries

“…They are currently under clinical investigation for the superficial femoral artery [5,6], and promising results of single-centers have been achieved in other arteriosclerotic lesions [7][8][9]. Furthermore, sirolimus eluting metallic stents were effective in reducing neointimal formation in porcine carotid arteries in a short-term study [10]. One major concern using metallic DES, however, remains after the drug's release, that is the chronic interaction between metal material and the vessel wall.…”