Nitinol intravascular stent: results of preclinical evaluation.

PURPOSE: To test an expandable nitinol intraluminal stent for hoop strength, biocompatibility, corrosion resistance, and patency. MATERIALS AND METHODS: Forty-four stents were implanted in the iliac arteries of 22 sheep. Follow-up was performed with angiography and histologic examination for up to 6 months. RESULTS: All but one stent remained widely patent during the follow-up period. Two stents in two sheep were placed incorrectly early in the study; these sheep were not followed up. Hoop strength was found to be superior to that of a similar, commercially available, self-expanding stent. Minimal corrosion was seen at 6 months, and the stent appears to be biocompatible. The stent has good radiopacity and deploys with minimal foreshortening. CONCLUSION: The stent can be reliably and safely deployed in the vascular system. Clinical trials in humans are warranted.