IN-VIVO EVALUATION OF A FLUORINE-ACRYL-STYLENE-URETHANE-SILICONE ANTITHROMBOGENIC COATING MATERIAL COPOLYMER FOR INTRAVASCULAR STENTS

Rationale and Objectives. We evaluated the effectiveness of a fluorine -acryl-styrene-urethane-silicone (FASUS) copolymer as an antithromboge nic coating material for intravascular stents in dogs. Methods. FASUS copolymer-coated stents were placed in the right iliac veins, and unco ated 304 stainless steel stents were placed in the left iliad veins. W e examined platelet deposition, microthrombus formation, and neointima l hyperplasia 4 weeks after stent placement by measuring the activity of In-111-labeled platelets, by using scanning electron microscopy, an d by measuring neointimal thickness. Results. Platelet deposition was significantly decreased on coated than on uncoated stents (p < .05). A less pronounced increase in red blood cell deposition was observed at the sites of the coated than uncoated stents (p < .05). Neointimal th ickness 4 weeks after stent placement also was significantly less at t he sites of the coated stents (0.27 +/- 0.08 mm versus 0.48 +/- 0.23 m m, P < .05). Conclusion. FASUS copolymer coating over the vascular ste nt is effective for preventing thrombus formation and neointimal hyper plasia.