Developed of spiral vortex-type artificial heart

澳大利亚脉动心室辅助装置（VAD）被命名为“螺旋涡流”（SV）泵，因为在运行期间泵壳内形成连续流线。在澳大利亚进行的慢性动物实验中，SV泵被放置在绵羊身体的左侧。在常规的过程中，实验羊可以在手术后几个小时内站起来。在实验期间，绵羊可以在容器中吃、喝和睡觉。在以3.0- 4.0 L/min的旁路流量进行VAD泵送期间，血浆游离血红蛋白水平小于10 mg/dl。目前，动物实验正在进行中，以确认该系统在接近“真实世界”条件下的优越性。然而，SV设计的优化必须在开发临床质量模型之前通过工程分析来实现。为了获得SV设计的基本数据，计划在日本使用两种不同的SV外壳进行比较流动可视化研究。试验结果表明，SV型泵的流量和入口水击特性与圆锥型泵无显著差异。然而，在收缩期，锥形泵的流出速度始终低于圆顶形泵。锥形通道内的周向流速也较低。然后，在舒张期建议采用锥形，以减少D-H连接处的停滞，而在收缩期建议采用锥形，以最大限度地减少剪切应力。最佳SV外壳设计应根据这些数据进行。

The Australian pulsatile ventricular assist device (VAD) has been named the "Spiral Vortex" (SV) pump after the continuous streamlines which develop within the pump housing during operation. In the chronic animal experiments performed in Australia, the SV pump was placed on the left side of the sheep's body. In a regular course, an experimental sheep can stand up in a few hours after the operation. The sheep can eat, drink and sleep in the container for the duration of the experiment. During VAD pumping with the bypass flow of 3.0-4,0 L/min, the level of plasma free hemoglobin was less than 10 mg/dl. At present, animal experiments are underway to confirm the superiority of the system in near "real-world" conditions. However, optimization of the SV design must be achieved through an engineering analysis prior to the development of a clinical quality model.In order to obtain fundamental data on the SV design, a comparative flow visualization study was planned in Japan using two different SV housings. Hydrodynamics test revealed that no significant difference in pump flow and inlet waterhammer between cone-shaped and dome-shaped SV pumps. However, outflow velocities in the cone-shaped pump were consistently lower than that in the dome-shaped during systole. and, peripheral flow velocities in the cone-shaped were also lower during diastole. Then, the domeshape recommended during the diastolic phase for decreasing the stagnation at D-H junction, whereas the cone-shape was recommended during the systolic phase for minimizing shear stress. The optimal SV housing design should be approached in the light of this data.