PLASMA TREATMENT EFFECTS ON THE TANTALUM STRECKER STENT IMPLANTED IN FEMORAL ARTERIES OF SHEEP

Purpose: To evaluate the effects of plasma treatment, a cleaning proce ss for removal of organic contaminants from the knit-wire surface of t antalum Strecker stents, on biocompatibility and thrombogenicity. Meth ods: A treated or untreated stent was randomly implanted in both femor al arteries of 15 sheep studied for periods of 4 (group 1), 15 (group 2), or 42 (group 3) days. Patency, histological changes, and mechanica l effects were compared by means of radiologic and pathologic controls . Results: Plasma treatment did not influence overall patency (93.3% v s 86.7%), maximal neointimal hyperplasia in groups 2 and 3 (801 +/- 12 3 vs 733 +/- 179 mum), or media thinning in any group (254 +/- 92 vs 2 85 +/- 72 mum), but modified the elastic properties of the stents by l imiting (p = 0.01) shortening at implantation. Conclusion: Plasma trea tment does not affect the biocompatibility and thrombogenicity of Stre cker stents implanted in normal femoral arteries of sheep but modifies their elastic properties. Further studies are needed to account for t his effect.