Comprehensive research concerned with the influence of flow state of artificial heart on living body by observation of microcirculation

虽然许多类型的连续流动的脑室辅助装置已经成为临床上用于心脏移植的桥梁，但没有人知道血流的脉动性是否对活体是必要的。为了解决这一问题，我们成功地研制了波动泵AH(UPAH)和电荷耦合器件(CCD)探头。通过计算机控制电机转速，UPAH可以瞬间改变其流型。CCD探头是一种植入式微型摄像机，用于实时观察微循环。本研究的目的是通过研制更完整的UPTAH和CCD探头，阐明活体搏动的必要性。4年来取得了以下成果：1)UPAHBlood的兼容性、耐久性以及尺寸和重量都有了很大的提高。植入UPAH的山羊在未使用抗凝剂的情况下最长存活4个月。开发了血液波形控制软件。2)以高倍率、调焦系统和小型化为目标。研制了一种直径2 mm、长2 mm的微透镜。镜头安装在直径8 mm、长60 mm的ccd相机中。14英寸电视屏幕上的总放大倍数为650倍，足以观察到毛细血管中的红细胞流动。它可以毫不费力地植入动物体内。残留的问题是病灶调节系统。3)UPAH下的微循环。当UPAH山羊从手术应激中恢复时，血流模式瞬间由搏动性转变为连续性。实验过程中观察球结膜微循环变化。到目前为止，观察到的现象如下：(1)毛细血管密度，即流动的毛细血管数量占总毛细血管数量的比例，下降了30%。(2)毛细血管内红细胞流率下降75%，恢复搏动性后部分未恢复。

Although many types of continuous flow ventricular assist devices have become to use clinically as the bridge to heart transplantation, no body knows whether the pulsatility of blood flow is essential for living body or not. We have succeeded the basic development to solve the problem ; undulation pump AH(UPAH) and CCD probe. UPAH can change instantaneously its flow patterns by computer control of motor rotational speed. CCD probe is implantable micro-camera to observe microcirculation chronically.The objective of this study is to clarify the necessity of pulsatility for the living body by developing more completely UPTAH and CCD probe. The following outcome has been gotten in these 4 years :1)UPAHBlood compatibility, durability and size ＆ weight were improved great deal. The goat implanted UPAH survived maximally 4 months without anticoagulant. The software to control blood waveform has also been developed.2)CCD probeHigh magnification, focus adjust system and miniaturization were the objective to be developed. A micro-lens, 2 mm in diameter and 2 mm long was developed. The lens was installed into a CCD camera having 8 mm in diameter and 60 mm long. Total magnification on 14 inch TV screen was 650 times, that was enough to observe the erythrocyte flow in a capillary vessel. It could be implanted in an animal without difficulty. Residual problem is focus adjusting system.3)Microcirculation under UPAHThe blood flow pattern was changed instantaneously from pulsatile to continuous when UPAH goat recover from surgical stress. The microcirculation was observed at bulbar conjunctiva during experiment. Following phenomena were observed until now : (1)Capillary density that is the ratio of the flowing capillaries to total capillary number, was decreased 30%. (2)The erythrocyte flow rate in the capillary was decreased 75 and some of them did not recover after the flow pattern returned to pulsatile.