Ahmed Maqsood, Hamilton George, Seifalian Alexander M
Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), Division of Surgery and Interventional Science, University College London, UK.
Annu Int Conf IEEE Eng Med Biol Soc. 2010;2010:251-4. doi: 10.1109/IEMBS.2010.5627472.
Small calibre (〈6mm) polytetrafluoroethylene (PTFE) bypass grafts have poor medium and long term patency due to the development of neointimal hyperplasia at the distal anastomosis. The inelasticity of PTFE is implicated in this mechanism of failure. We have developed a novel polyhedral oligomeric silsesquioxane (POSS) nanocage incorporated into a poly(carbonate)urethane (PCU) biomaterial with enhanced biostability and improved antithrombogenicity making it ideal for cardiovascular applications. In this study the compliance and viscous component of a POSS-PCU small calibre graft was measured using a biomimetic pulsatile flow circuit and wall tracking ultrasound. A POSS-PCU graft displays elastic and viscous behaviour similar to the native artery. Furthermore, platelet adhesion and activation studies suggest POSS-PCU is a more biocompatible material than current industry favourite ePTFE. Alleviating the thrombogenicity of grafts and the mechanical mismatch between artery and graft is encouraging for the short and long term patency of the POSS-PCU graft.
小口径（<6mm）聚四氟乙烯（PTFE）旁路移植物由于远端吻合口处新生内膜增生，中长期通畅性较差。PTFE的无弹性与这种失败机制有关。我们开发了一种新型的多面体低聚倍半硅氧烷（POSS）纳米笼，将其掺入聚碳酸酯聚氨酯（PCU）生物材料中，具有增强的生物稳定性和改善的抗血栓形成性，使其成为心血管应用的理想材料。在本研究中，使用仿生脉动流回路和壁跟踪超声测量了POSS-PCU小口径移植物的顺应性和粘性成分。POSS-PCU移植物表现出与天然动脉相似的弹性和粘性行为。此外，血小板粘附和活化研究表明，POSS-PCU是一种比目前行业青睐的ePTFE更具生物相容性的材料。减轻移植物的血栓形成性以及动脉与移植物之间的机械不匹配，对POSS-PCU移植物的短期和长期通畅性是令人鼓舞的。
