In-vitro biomechanical studies of endovascular devices

Abstract

Preliminary studies have revealed that stainless steel (SS) and nickel titanium (NiTi) stents undergo corrosion in vivo, with significant release of metallic ions into surrounding tissues. It is believed that high concentrations of metal ions from both SS and NiTi stents are toxic to vascular smooth muscle cells and stimulate both inflammatory and fibrotic reactions leading to neointimal formation and a predisposition to device failure. To separate the mechanical effects from the local environmental effects on the stent surface, invitro mechanical studies were performed on various combinations of stents under low and high curvature and in overlapping positions to compare the results of fretting, pitting and gouging with the explanted stents.