[Efficacy and Safety of a Newly Developed Self-Expanding Open-Cell Type Nitinol Stent for Peripheral Arteries: A Preclinical Study in Minipigs]

Abstract

Purpose: To evaluate the safety and efficacy of the newly designed open-cell type self-expandable nitinol stent (NiTi-stent) for peripheral arteries.

Materials and methods: Twenty-eight limbs of 14 minipigs were randomly assigned to the NiTi-stent group or conventional nitinol stent group. Stents were symmetrically implanted into the iliac arteries of each animal using carotid artery approach and were observed for 1 month (n = 5) and 6 months (n = 9). The angiographic lumen diameter (ALD), late lumen loss, angiographic stenosis, histomorphometric lumen area, neointimal area, and area stenosis were analyzed and compared between the groups.

Results: Stent migration, stent fracture, or thrombus formation were not observed in either group. At the 1-month follow-up, the neointimal area (p = 0.008) and area stenosis (p = 0.016) were significantly smaller in the NiTi-stent group than in the control group. At the 6-months follow-up, the NiTi-stent group showed significantly larger ALD (p = 0.014), less late lumen loss (p = 0.019), less angiographic stenosis (p = 0.014), larger lumen area (p = 0.040), and smaller neointimal area and area stenosis (p = 0.004 and p = 0.014, respectively) compared with the control group.

Conclusion: The NiTi-stent is as safe and effective as the conventional nitinol stent and induces less neointimal hyperplasia in a minipig iliac artery model.