Yuan J G, Ohki T, Marin M L, Quintos R T, Krohn D L, Beitler J J, Veith F J
Department of Surgery, Montefiore Medical Center, The University Hospital for the Albert Einstein College of Medicine, New York, New York 10467, USA.
J Endovasc Surg. 1998 Nov;5(4):349-58. doi: 10.1583/1074-6218(1998)005<0349:TEONPC>2.0.CO;2.
To report an experimental study investigating the ability of nonporous polytetrafluoroethylene (PTFE) covering on a metallic stent to retard the development of neointimal hyperplasia (NIH).
Three groups of Hanford miniature swine underwent standardized balloon injury to both external iliac arteries. Group I animals (control) received balloon injuries only. Group II had the site of balloon injury supported by a properly sized, balloon-expandable Palmaz stent placed directly over the injury site. Group III animals received a Palmaz stent covered with PTFE graft. All animals underwent arteriography immediately after intervention and again prior to sacrifice and specimen harvest at 4 weeks. The specimens were examined grossly and histologically at the proximal, middle, and distal segments for NIH development.
Uncovered stents developed significantly more NIH (p < 0.0001) and greater luminal narrowing (p < 0.001) than the controls. PTFE-covered stents (group III) exhibited less NIH (p < 0.001) and luminal reduction (p < 0.01) than bare stents (group II) at the middle portion of the stent-graft, but the PTFE cover had no effect on NIH and lumen reduction at the proximal or distal ends of the prosthesis.
PTFE-covered stents retarded NIH at 4 weeks, but only at the midportion of the devices; the covering did not prevent neointimal pannus ingrowth at the proximal and distal ends.
报告一项实验研究，该研究旨在探究金属支架上的无孔聚四氟乙烯（PTFE）涂层抑制新生内膜增生（NIH）发展的能力。
三组汉福德小型猪的双侧髂外动脉均接受标准化球囊损伤。第一组动物（对照组）仅接受球囊损伤。第二组在球囊损伤部位放置尺寸合适的球囊可扩张帕尔马兹支架，直接覆盖在损伤部位。第三组动物接受覆盖有PTFE移植物的帕尔马兹支架。所有动物在干预后立即进行血管造影，并在4周后处死和采集标本前再次进行血管造影。对标本的近端、中段和远端进行大体和组织学检查，以观察NIH的发展情况。
与对照组相比，未涂层支架的NIH显著增多（p < 0.0001），管腔狭窄更严重（p < 0.001）。在支架移植物的中段，PTFE涂层支架（第三组）的NIH（p < 0.001）和管腔缩小程度（p < 0.01）均低于裸支架（第二组），但PTFE涂层对假体近端或远端的NIH和管腔缩小无影响。
PTFE涂层支架在4周时可抑制NIH，但仅在装置的中段；该涂层不能防止近端和远端新生内膜的向内生长。
