Graham T R, Dasse K, Coumbe A, Salih V, Marrinan M T, Frazier O H, Lewis C T
London Hospital, UK.
Eur J Cardiothorac Surg. 1990;4(4):182-90. doi: 10.1016/1010-7940(90)90002-h.
Implantable left ventricular assist systems are being developed for long term clinical use. Prototype devices are currently used as extended mechanical bridges to cardiac transplantation. The Thermo Cardiosystems Inc. (TCI) pneumatic pusher plate left ventricular assist device (LVAD) features textured blood contacting surfaces to encourage the formation of an adherent fibrin-cellular coagulum. This serves as the foundation for the development of a neo-intimal lining. The TCI LVAD was implanted in 6 male patients (age range 22-53 years) between 1986 and 1988. The duration of implantation ranged from 1-41 days. No clinical thromboembolic events or pump-related thromboembolism occurred and none was evident at necropsy. The six device linings have been fully evaluated. Explanted devices were free of thrombus and calcification. Lining samples for light and electron microscopy were collected from areas of the diaphragm identical for flex and blood shear conditions and from high and low shear areas on the static housing. Islands of collagenous tissue were deposited on the static housing amongst compact fibrin. By day 13, cells populated the surface of the developing neo-intima overlying the diaphragm. By 41 days, the surface cell density increased and the cells became spindle shaped and relatively orientated in the high shear/flex area. Immunohistochemical techniques suggest that these cells are of mesenchymal origin. Textured blood contacting surfaces appear satisfactory in the preliminary clinical use of this device.
可植入式左心室辅助系统正在研发以用于长期临床应用。目前，原型设备被用作心脏移植的延长机械桥接装置。热控心血管系统公司（TCI）的气动推板左心室辅助装置（LVAD）具有带纹理的血液接触表面，以促进形成附着的纤维蛋白 - 细胞凝块。这为新内膜衬里的形成奠定了基础。1986年至1988年间，6名男性患者（年龄范围22 - 53岁）植入了TCI LVAD。植入时间为1 - 41天。未发生临床血栓栓塞事件或与泵相关的血栓栓塞，尸检时也未发现明显异常。对六个装置的衬里进行了全面评估。取出的装置没有血栓和钙化。从隔膜上与弯曲和血液剪切条件相同的区域以及静态外壳上的高剪切和低剪切区域采集用于光镜和电镜检查的衬里样本。在致密的纤维蛋白中，胶原组织岛沉积在静态外壳上。到第13天，细胞在隔膜上方发育中的新内膜表面聚集。到41天时，表面细胞密度增加，细胞变成纺锤形，并在高剪切/弯曲区域相对定向排列。免疫组织化学技术表明这些细胞起源于间充质。在该装置的初步临床应用中，带纹理的血液接触表面看起来令人满意。
