Froelich J J, Alfke H, Wilke A, Ramaswamy A, Barth K H, Hoppe M, Wagner H J, Klose K J
Department of Radiology, Philipps-University Hospital, Marburg, Germany.
J Vasc Interv Radiol. 1999 Mar;10(3):329-38. doi: 10.1016/s1051-0443(99)70039-4.
This experimental study was conducted to evaluate neointimal thickness, lumen diameters, and histologic changes in normal and stenotic porcine iliac arteries following placement of self-expanding nitinol Strecker stents.
Neointimal trauma causing slight vascular stenosis was induced unilaterally within external iliac arteries of 12 swines by means of endothelial abrasion and high cholesterol diet. Nitinol Strecker stents were placed within the stenotic and the normal contralateral vascular segments. For histopathologic evaluation, the pigs were killed 12 or 24 weeks after stent placement and luminal diamters were evaluated angiographically.
Excluding one occlusion, 15% narrowing of the lumen diameter was induced unilaterally (P = .002). Initial luminal gain after stent placement was greater for stenotic than for normal arteries. The amount of neointima thickness was not different between stenotic and normal vessels (P > .05). Comparing vascular diameters before stent placement and at follow-up, luminal loss due to neointima proliferation was 22% within normal arteries (P = .0002), while a luminal gain by 15% was found within the stenotic arteries (P = .008). Maturation of neointima and endothelial coverage were complete after 24 weeks.
Even though nitinol Strecker stents induce excessive neointimal proliferation, stenotic arteries seem to profit from great early luminal gain resulting in 15% of vascular expansion at follow-up while slight stenosis is induced within normal iliac arteries.
本实验研究旨在评估自膨胀镍钛诺Strecker支架植入正常和狭窄猪髂动脉后的新生内膜厚度、管腔直径及组织学变化。
通过内皮磨损和高胆固醇饮食，在12头猪的单侧髂外动脉内诱导造成轻微血管狭窄的新生内膜损伤。将镍钛诺Strecker支架植入狭窄及对侧正常血管段。为进行组织病理学评估，在支架植入后12周或24周处死猪，并通过血管造影评估管腔直径。
排除一处闭塞情况，单侧管腔直径缩小15%（P = .002）。支架植入后狭窄动脉的初始管腔增益大于正常动脉。狭窄血管与正常血管的新生内膜厚度无差异（P > .05）。比较支架植入前及随访时的血管直径，正常动脉内新生内膜增生导致的管腔损失为22%（P = .0002），而狭窄动脉内管腔增益15%（P = .008）。24周后新生内膜成熟且内皮覆盖完整。
尽管镍钛诺Strecker支架会诱导过度的新生内膜增生，但狭窄动脉似乎从早期较大的管腔增益中获益，随访时血管扩张达15%，而正常髂动脉内则诱导产生轻微狭窄。
