DEVELOPMENT OF A TOTALL IMPLANTABLE, MOTOR DRIVEN ARTIFICIAL HEART SYSTEM

开发完全植入式电机驱动人工心脏系统

• 批准号: 10044232
• 负责人: TAKATANI Setsuo
• 金额: $ 2.82万
• 依托单位: TOKYO MEDICAL AND DENTAL UNIVERSITY (1999-2001)Yamagata University (1998)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10044232/
• 关键词: Electromechanical TAH; Electromechanical VAD; Heart Transplantation; Continuous Flow Pumps; Centrifugal Blood Pump; Biocompatibility; Durability; Compliance Chamber; 全置換型人工心臓; 補助人工心臓; Ti-6Al-7Nbチタン合金; ポリウレタン3尖弁; 流れの可視化; 拍動流補助人工心臓; 連続流補助人工心臓

In this project, in collaboration with Prof. H Reul's group of Helmholtz Institute of Biomedical Engineering, TechnicalUniversity Aachen, Aachen, Germany, the main objective was to develop a totally implantable, ultracompact electromechanical total artificial heart (TAH) and ventricular assist device (VAD). Both TAH and VAD Systems are based on transmitting the electrical energy through skin using a transcutaneous energy transmission (TET) system to power the implanted blood pump. The implanted components include thes pumping unit, compliance chamber, internal battery, and the controller. The TAH pumping unit is an one-piece design sandwiching an electromechanical actuator between the left and right pumps. The VAD was made using the same actuator as TAH's and covering the right side of the TAH with a backplate. The diameter and thickness of the TAH are 90mm and 70mm, respectively, and its volume is 400cc with the weight being 450g. Those of the VAD are 90mm and 56mm, respectively, yiel … More ding the volume of 275cc and weight of 460g. Although downsized, the maximum floy of 8L/min was obtained at the pumping rate of 160BPM. The power required for TAH ranged from 10 to 15 watts, while that of VAD from 5 to 8 watts. The maximum electrical to hydraulic efficiency of the TAH was 13.5% and that for VAD was 23%.As a volume compensator, 55cc air-filled chamber was designed for TAH, while for VAD 75cc chamber. The flexing membrane was made of polyurethane with its thickness being around 0.2mm. The secondary rechargeable batteries such as NiMH and Li-ion were tested for their performance with the TAH and VAD. With the terminal voltage of 16V, both batteries were able to power the artificial heart for over a duration of 2 hours.In vivo studies with VAD and TAH have just started to evaluate their durability and biocompatibility. When long term durability and biocompatibility were demonstrated, we will move into clinical trials.In addition to pulsatile systems, we also started to design and evaluate the centrifugal blood pump. The centrifugal blood pump is a tri-pod mechanism supporting the impeller. The basic performance in terms of head pressure-flow was obtained. The results indicated that the prototype pump meet the requirements as the left ventricular assist device. However, because of high friction wear at the tri-pod and polyethylene groove interface, we changed the pump design to a single pivot bearing mechanism. With improvement in impeller stability, this pump may meet requirements for clinical ventricular assist device. Further study will follow in future.As a monitoring system of the artificial heart implanted patient, an optical reflectance sensor to measure blood hemoglobin level and oxygen saturation was developed. Its accuracy in terms of hemoglobin level and oxygen saturation was evaluated using bovine blood. The results indicated feasibility of the sensor for continuous patient monitoring, provided its long term performance has been proven in animals.Through collaboration with Helmohotz Institute, we were fortunate to exchange not only the staff members, but also students. We received three master's students who worked on the optical sensor project. One of our students spent six months in Aachen learning computation fluid dynamic approach to analyze blood flow pattern inside the continuous flow devices. Also, we organized two Japan-Germany artificial heart symposiums, one in 1998 and the other in 2000. Through these exchange programs, we were fortunate to learn valuable information to help better design and analyze blood pump data. I think exchange program provided valuable experience to the students as well as staff members. Less

本项目与德国亚琛的亚琛工业大学亥姆霍兹生物医学工程研究所的H Reul教授小组合作，主要目标是开发一种完全植入式、超紧凑型机电全人工心脏（TAH）和心室辅助装置（VAD）。TAH和VAD系统均基于使用经皮能量传输（泰特）系统通过皮肤传输电能，为植入式血泵供电。植入组件包括泵送装置、顺应性腔室、内部电池和控制器。天阿公司的抽油机为一体式设计，在左泵和右泵之间安装了一个机电执行器。VAD使用与TAH相同的致动器制成，并用背板覆盖TAH的右侧。TAH的直径和厚度分别为90 mm和70 mm，体积为400 cc，重量为450 g。VAD分别为90 mm和56 mm， ...更多信息 体积为275 cc，重量为460 g。虽然小型化，但在160 BPM的泵送速率下获得了8L/min的最大絮体。TAH所需功率为10 - 15 W，VAD所需功率为5 - 8 W。TAH的最大电液效率为13.5%，VAD的最大电液效率为23%，作为容积补偿器，TAH设计了55 cc的充气室，VAD设计了75 cc的充气室。柔性膜由聚氨酯制成，其厚度约为0.2mm。使用TAH和VAD测试了NiMH和Li离子等二次可充电电池的性能。两种电池的端电压均为16 V，均能为人工心脏供电超过2小时。VAD和TAH的体内研究刚刚开始，以评估其耐用性和生物相容性。当长期耐用性和生物相容性得到证明后，我们将进入临床试验。除了脉动系统，我们还开始设计和评估离心血泵。离心血泵是一个支撑叶轮的三脚架机构。得到了该泵的基本性能。实验结果表明，该原型泵符合左心室辅助装置的要求。然而，由于三脚架和聚乙烯槽界面处的高摩擦磨损，我们将泵设计改为单枢轴轴承机制。该泵叶轮稳定性提高，可满足临床心室辅助装置的要求。作为人工心脏植入患者的监护系统，研制了一种用于测量血红蛋白水平和血氧饱和度的光学反射传感器。使用牛血评价其血红蛋白水平和氧饱和度方面的准确性。结果表明，只要其长期性能已在动物身上得到证明，该传感器用于连续患者监测的可行性。通过与Helmohotz研究所的合作，我们不仅有幸交换了工作人员，还交换了学生。我们接收了三名从事光学传感器项目的硕士生。我们的一个学生花了六个月的时间在亚琛学习计算流体动力学方法来分析连续流装置内的血液流动模式。此外，我们还分别于1998年和2000年组织了两次日本-德国人工心脏研讨会。通过这些交流项目，我们有幸学到了宝贵的信息，有助于更好地设计和分析血泵数据。我认为交流项目为学生和工作人员提供了宝贵的经验。少

项目成果

Takatani S,Sakamoto T: "Mechanical circulatory support devices for bridge to heart transplantation, bridge to recovery or destination therapy."J Artificial Organs. 3. 75-84 (2000)

Takatani S，Sakamoto T：“用于心脏移植、恢复或目的地治疗桥梁的机械循环支持装置。”J Artificial Organs。

海和,高谷他: "磁気浮上型遠心ポンプ内における光学的手法による血液のヘマトクリット測定" 人工臓器. 28巻1号. 173-177 (1999)

Kaiwa, Takatani 等人：“在磁悬浮离心泵中使用光学方法测量血液血细胞比容”，Artificial Organs，第 28 卷，第 1. 173-177 期（1999 年）。

Takatani S, Nakamura M, Ohuchi K, Nogawa M, Sakamoto T: "Ultracompact, Completely Implantable Electro-mechanical permanent TAH"Journal of Congestive Heart Failure and Circulatory Support. 1(4). 161-166 (2001)

Takatani S、Nakamura M、Ohuchi K、Nokawa M、Sakamoto T：“超紧凑、完全植入式机电永久 TAH”充血性心力衰竭和循环支持杂志。

Kaiwa T,Takatani S et al: "Measurement of blood hematocrit inside the magnetically suspended centrifugal pump using an optical technique" Artificial Organs. (in press). (1999)

Kaiwa T、Takatani S 等人：“使用光学技术测量磁悬浮离心泵内的血细胞比容”人工器官。

Yuhki A,Nogawa M,Takatani S: "Development of a compact, seal-less, tripod supported, magnetically driven centrifugal blood pump"Artificial Organs. 24(6). 501-505 (2000)

Yuhki A、Nokawa M、Takatani S：“开发紧凑型、无密封、三脚架支撑、磁驱动离心血泵”人工器官。