Plasma treatment effects on the tantalum Strecker stent implanted in femoral arteries of sheep.

ABSTRACT

PURPOSE: To evaluate the effects of plasma treatment, a cleaning process for removal of organic contaminants from the knit-wire surface of tantalum Strecker stents, on biocompatibility and thrombogenicity. METHODS: A treated or untreated stent was randomly implanted in both femoral arteries of 15 sheep studied for periods of 4 (group 1), 15 (group 2), or 42 (group 3) days. Patency, histological changes, and mechanical effects were compared by means of radiologic and pathologic controls. RESULTS: Plasma treatment did not influence overall patency (93.3% vs 86.7%), maximal neointimal hyperplasia in groups 2 and 3 (801 +/- 123 vs 733 +/- 179 microns), or media thinning in any group (254 +/- 92 vs 285 +/- 72 microns), but modified the elastic properties of the stents by limiting (p = 0.01) shortening at implantation. CONCLUSION: Plasma treatment does not affect the biocompatibility and thrombogenicity of Strecker stents implanted in normal femoral arteries of sheep but modifies their elastic properties. Further studies are needed to account for this effect.