Takami Y, Yamane S, Makinouchi K, Niimi Y, Sueoka A, Nosé Y
Nagoya University School of Medicine, Department of Thoracic Surgery, Japan.
Artif Organs. 1998 Sep;22(9):753-8. doi: 10.1046/j.1525-1594.1998.6184r.x.
A totally implantable centrifugal artificial heart has been developed in which a pivot bearing supported centrifugal pump is used as a blood pump. The following have been adopted as blood contacting materials in our pump: titanium alloy (Ti-6A1-4V) for the housing and impeller, alumina ceramic (Al2O3) for the male pivots, and ultrahigh molecular weight polyethylene (PE) for the female pivots. Greater antithrombogenicity is required for an implantable blood pump. To examine the thrombogenicity of these materials, we evaluated in vitro platelet adhesion and activation, which may play key roles in thrombogenesis on foreign surfaces. Ti-6A1-4V, Al2O3, and PE were compared with polycarbonate (PC), silicone carbide (SiC), and pure titanium (pTi). Platelet adhesion was assessed using monoclonal antibody (CD61) directed against glycoprotein IIIa. Platelet activation was evaluated by measuring P-selectin (GMP-140) released from irreversibly activated platelets. Each material with a surface area of 16.6 cm2 was incubated with 2.5 ml of plasma or 2.5 ml of heparinized fresh whole blood for 3 h at 37 degrees C. The optical density (OD) at a wavelength of 450 nm for CD61 was 0.93+/-0.35 in PC, 0.34+/-0.13 in PE, 0.27+/-0.13 in pTi, 0.26+/-0.01 in Al2O3, 0.21+/-0.04 in SiC, and 0.12+/-0.12 in Ti-6A1-4V. The GMP-140 levels of the tested materials were not significantly different from the control value (45.9+/-7.2 ng/ml). These results indicate that Al2O3, PE, and Ti-6A1-4V, which are incorporated into our implantable centrifugal pump, have satisfactory antithrombogenic properties in terms of platelet adhesion. However, platelet activation by any material was not observed under the static condition in this study.
一种完全植入式离心人工心脏已被研发出来，其中一个由枢轴轴承支撑的离心泵被用作血泵。在我们的泵中采用了以下作为血液接触材料：外壳和叶轮用钛合金（Ti-6Al-4V），阳枢轴用氧化铝陶瓷（Al2O3），阴枢轴用超高分子量聚乙烯（PE）。植入式血泵需要更高的抗血栓形成性。为了检测这些材料的血栓形成性，我们评估了体外血小板粘附和活化情况，这可能在异物表面血栓形成中起关键作用。将Ti-6Al-4V、Al2O3和PE与聚碳酸酯（PC）、碳化硅（SiC）和纯钛（pTi）进行比较。使用针对糖蛋白IIIa的单克隆抗体（CD61）评估血小板粘附。通过测量从不可逆活化血小板释放的P-选择素（GMP-140）来评估血小板活化。将每种表面积为16.6平方厘米的材料与2.5毫升血浆或2.5毫升肝素化新鲜全血在37℃下孵育3小时。PC中CD61在450纳米波长处的光密度（OD）为0.93±0.35，PE中为0.34±0.13，pTi中为0.27±0.1,3，Al2O3中为0.26±0.01，SiC中为0.21±0.04，Ti-6Al-4V中为0.12±0.12。受试材料的GMP-140水平与对照值（45.9±7.2纳克/毫升）无显著差异。这些结果表明，用于我们植入式离心泵的Al2O3、PE和Ti-6Al-4V在血小板粘附方面具有令人满意的抗血栓形成特性。然而，在本研究的静态条件下未观察到任何材料引起的血小板活化。
