抄録
To investigate the effects of gaps between the individual coils of wire of a shape memory nitinol alloy intravascular endoprosthesis, 44 stents with and without gaps were implanted transluminally into the infrarenal ab-dominal aortas of 22 atherosclerotic rabbits after balloon angioplasty. The stent size was 3.5mm in outer diameter and 15mm in length. The cross section of the wire had a rectangular shape, sized 0.15 by 0.33mm. The gaps between coils of wire were less than 0.03mm in one design, and 0.33mm in the other design. Digital subtraction angiography was done at 4 weeks, 8 weeks, 12 weeks, 16 weeks, 20 weeks and 24 weeks after scent implantation. Eleven of 22 rabbits were alive and followed longer than 12 weeks. Restenosis rate in these rabbits within stents with gaps were significant-ly lower than those without gaps: 11.8±5.2% vs 31.5±14.5% at 12 week (p<0.001, paired T test), 16.6±5.8% vs 37.4±10.0% at 24 week DSA (p<0.001). These results suggested that the placement of gaps between wire pitches reduced the neointimal thickness within stents and improved the patency rats.
