a State Key Laboratory of Precision Measurement Technology and Instruments , Tsinghua University , Beijing , China.
b Division of Advanced Manufacturing , Graduate School at Shenzhen, Tsinghua University , Shenzhen , China.
Comput Assist Surg (Abingdon). 2017 Dec;22(sup1):221-231. doi: 10.1080/24699322.2017.1389400. Epub 2017 Oct 26.
Ventricular assist devices (LVADs) are increasingly recognized for supporting blood circulation in heart failure patients who are non-transplant eligible. Because of its volume, the traditional pulsatile device is not easy to implant intracorporeally. Continuous flow LVADs (CF-LVADs) reduce arterial pulsatility and only offer continuous flow, which is different from physiological flow, and may cause long-term complications in the cardiovascular system. The aim of this study was to design a new pulsatile assist device that overcomes this disadvantage, and to test this device in the cardiovascular system. Firstly, the input and output characteristics of the new device were tested in a simple cardiovascular mock system. A detailed mathematical model was established by fitting the experimental data. Secondly, the model was tested in four pathological cases, and was simulated and coupled with a fifth-order cardiovascular system and a new device model using Matlab software. Using assistance of the new device, we demonstrated that the left ventricle pressure, aortic pressure, and aortic flow of heart failure patients improved to the levels of a healthy individual. Especially, in state IV level heart failure patients, the systolic blood pressure increased from 81.34 mmHg to 132.1 mmHg, whereas the diastolic blood pressure increased from 54.28 mmHg to 78.7 mmHg. Cardiac output increased from 3.21 L/min to 5.16 L/min. The newly-developed assist device not only provided a physiological flow that was similar to healthy individuals, but also effectively improved the ability of the pathological ventricular volume. Finally, the effects of the new device on other hemodynamic parameters are discussed.
心室辅助装置（LVADs）越来越被认为可支持非移植适应证心力衰竭患者的血液循环。由于其体积较大，传统的搏动装置不易植入体内。连续流 LVAD（CF-LVAD）降低了动脉搏动性，仅提供连续流动，这与生理流动不同，可能会在心血管系统中引起长期并发症。本研究旨在设计一种克服这一缺点的新型搏动辅助装置，并在心血管系统中对该装置进行测试。首先，在简单的心血管模拟系统中测试了新装置的输入和输出特性。通过拟合实验数据，建立了详细的数学模型。其次，在四种病理情况下测试了该模型，并使用 Matlab 软件对其进行了模拟和与第五阶心血管系统和新装置模型的耦合。借助新装置，我们证明心力衰竭患者的左心室压力、主动脉压和主动脉流量改善至健康个体的水平。特别是在 IV 级心力衰竭患者中，收缩压从 81.34mmHg 增加到 132.1mmHg，而舒张压从 54.28mmHg 增加到 78.7mmHg。心输出量从 3.21L/min 增加到 5.16L/min。新开发的辅助装置不仅提供了类似于健康个体的生理流量，而且还有效地改善了病理性心室容积的能力。最后，讨论了新装置对其他血液动力学参数的影响。
