Low-Dose Radioactive Endovascular Stents Prevent Smooth Muscle Cell Proliferation and Neointimal Hyperplasia in Rabbits

Abstract

The results of this study clearly indicate that low-dose radioactive endovascular stents potently inhibit SMC proliferation and neointimal hyperplasia in rabbits.

Paclitaxel Stent Coating Inhibits Neointimal Hyperplasia at 4 Weeks in a Porcine Model of Coronary Restenosis

“…Long-term studies should reveal whether cellular repair mechanisms respond to injury and cytotoxicity by overcompensation; this might reduce the long-term therapeutic benefit of paclitaxel, particularly at the high dose, at which medial wall necrosis and neointimal inhibition were significant. The requirement for long-term follow-up is underscored by the disparity between 1-month data 17,18 and long-term results 6,19 obtained with intracoronary brachytherapy, which is complicated by a late dose-dependent increase in neointimal formation and delayed healing of the endothelium. Further study will determine whether local paclitaxel delivery produces a sustained benefit or whether complications similar to those associated with brachytherapy diminish its therapeutic potential.…”

Experimental intracoronary stenting: comprehensive experience in a porcine model

“…Regarding these aspects, the authors like to call the present porcine model as an ideal experimental set-up not only for the test of novel, intracoronary stent devices, but also for the study of adjuvant therapeutic strategies, such as (i) inhibition of neointimal proliferation by a protein adduct of nitric oxide (Marks et al 1995) or an endothelin receptor antagonist (Ferrer et al 1995); (ii) endovascular irradiation via low-dose radioactive stents (Hehrlein et al 1995); and (iiil acceleration of stent endothelialization by local delivery of growth factors (Van Belle et al 1997 …”

Radiation therapy to prevent coronary artery restenosis

“…They took stainless steel stents (Palmaz-Schatz stents) and made them radioactive in a nuclear reactor. 32 The stents were highly effective at inhibiting neointima formation but might be problematic for permanent implantation as some of the isotopes created have very long half-lives. Consequently, this same group of researchers and others investigated the effects of stents implanted with radioactive phosphorous ( 32 P) 33.34 Subsequently, this stent was tested in pig coronary arteries at various levels of radioactivity.…”

“…The first trial of a 32 and is in no way optimal as a carrier to deliver a homogenous dose of radiation to the vessel wall. A new stent (BX Stent) has been developed which may be more optimal for delivering radiation and studies using this stent are currently underway.…”