Development of a totally implantable ventricular assist device system with improved antithrombogenicity and portability

开发具有改进的抗血栓形成性和便携性的完全植入式心室辅助装置系统

• 批准号: 14370369
• 负责人: HOMMA Akihiko
• 金额: $ 8.83万
• 依托单位: National Cardiovascular Center Research Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14370369/
• 关键词: Ventricular Assist Device(VAD); Implantable system; Wearable system; Portable VAD driver; Electrohydraulic actuator; Monitoring system; Blood pump; Volume compensation chamber; 補助人工心臓システム; コンプライアンスチャンバ; コプライアンスチャンバ

We have been developing an ultra-compact and low-noise portable pneumatic VAD driver in order to improve patient s quality of life in terms of providing better mobility and lower noise environment. The driver utilizes an electtohydraulic actuator instead of an air compressor. Oil pressure through a hydraulic/neumatic converting chamber, generate air pressures which drive a pneumatic blood pump. These technologies realized an ultra-compact size (35 x 30 x 45 cm), a light weigh (13 kg) and low-noise (39 dB). Furthermore, the driver is carried in safety using soft wheels axis against a bumpy ground and is protected by the urethane body surface against fall-down. This driver can be actuated with only one-tenth power consumption (45 w) in comparison with conventional console type driver and can be run for 2 hours with two internal rechargeable nickel metal-hydride batteries. This driver provide fill to empty driving mode, and pump output is continuing estimated for alarm. The durability has … More been confirmed in a bench test of over 15,000 hours. In vitro testing with Toyobo pneumatic VAD demonstrated a sufficient pump performance of up to 7 L/min. In vivo evaluation for over 3 months was also carried out in a left ventricular assist model using 6 adult goats without any failure. We conclude that this driver provide better quality of life to the patients with long-term pneumatic VAD support.Electrohydraulic ventricrlar assist device(EHVAD) systems have been developed. The EHVAD system is developed by using the left blood pump and electrohydraulic actuator of EHTAH, which was packaged with a volume compensation chamber. The system weight was 1160g. The maximum flow rate was 8.8 L/min and the maximum efficiency was 14.2 %.The system was implanted in 3 calves as small as 61 kg. One of these lived for 90 days. The estimated cardiac output was 4 L/min. These results indicate that EHVAD system has the potential to be a totally implantable system.A Transcutaneous energy transfersystem(TETS), a transcutaneous optical telemetry system(TOTS), and an internal battery have been developed. The system performance was evaluated in animal experiments using Electrohydraulic total artificial heart(EHTAH) system. The system was driven by the TET during normal operation of approximately 21 W input power. The system was also driven by the internal battery everyday, as per prescribed protocol. In the case of 40 minutes of discharge, the internal battery was fully charged for 3 hours. The DC to DC transmission efficiency of the TET was maintained at nearly 85 %. Driving parameters were transmitted through the skin with the TOTS at 9600 bps.We have developed a new monitoring method of the pump diaphragm positions for optimal driving of an electrohydraulic artificial heart system. The pump unit comprises polyurethane-made diaphragm-type blood pumps and an energy converter that reciprocates and delivers hydraulic silicone oil to the alternate blood pumps. Two ultrasound crystals of 2.4 mm diameter are fixed to both sides of the pump housing on a maximum stroke axis with 50 mm length. The ultrasound propagates through the blood chamber, the diaphragm, and the oil chamber. Propagation time of the ultrasound varies according to the diaphragm position because propagation speed of blood 1540 m/s is different from that of silicone oil 908 m/s. The propagation time varied in proportion to the diaphragm position estimated from observation and driving oil pressure wave forms in an overflow type mock circulation test. The propagation time reached to the maximum value of 0.054 ms and the minimum value of 0.033 ms at full-eject and full-fill states, respectively. Linear correlation was observed between the cardiac output and product of the change of propagation time multiplied by heart rate in the range of 1 to 9 L/min. The correlation coefficient was r=0.97. These results indicate that the diaphragm position is detected by the propagation time and the cardiac output is computed by the change of propagation time without a flowmeter.We also have developed computer simulation system for anatomical fitting study of the implantable artificial organ. A three-dimensional image of the chest cavity was reconstructed from human CT scan images. After removing the ventricles, the pump unit was implanted and connected to atriums and blood vessels on the computer model to decide a suitable design and fitting.Pocket infection is a serious major problem for the patients with an implantable VAD or TAH system. For reducing the risk of this type of infection, it is a reasonable approach to coat the device outer surface with tissue-compatible soft material that can alleviate mechanical vibration of the device and stress between the rigid device and the surrounding tissue. We developed a novel porous device-coating material that imparts excellent tissue-compatibility. This material, consisting of segmented polyurethane with a 3D reticulated structure, has tissue-like flexibility and sufficient mechanical strength. The test materials were potted in a silicone tube, and implanted into subcutaneous tissue of an adult goat. After 1 year implantation, no inflammatory or necrotic foci were observed in the infiltrated tissue, thus demonstrating sufficient tissue ingrowth into the material to form tight interconnections. In conclusion, the newly developed material may be a suitable outer surface coating material for implantable artificial heart. Less

我们一直在开发一种超小型、低噪音的便携式气动VAD驱动器，以改善患者S的生活质量，提供更好的移动性和更低的噪声环境。驾驶员使用电液执行机构而不是空气压缩机。通过液压/气动转换腔的油压，产生驱动气动血泵的气压。这些技术实现了超紧凑的尺寸(35 x 30 x 45厘米)、重量轻(13千克)和低噪音(39分贝)。此外，驾驶员使用软轮轴在颠簸的地面上安全携带，并由氨基甲酸酯车身表面保护，以防摔倒。与传统的控制台类型驱动器相比，该驱动器的功率消耗仅为十分之一(45W)，并且可以使用两个内部可充电的金属氢化物镍电池运行2小时。该驱动器为空驱动模式提供填充，并继续估计泵输出以供报警。经久耐用有…在超过15,000个小时的台架测试中，更多的得到了确认。丰田气动VAD的体外测试表明，泵的性能高达7 L/分钟。在左心室辅助模型中，6只成年山羊也进行了3个月以上的体内评估，没有任何失败。我们的结论是，这种驱动器为长期使用气动VAD支持的患者提供了更好的生活质量。电液脑室辅助装置(EHVAD)系统已经开发出来。EHVAD系统是利用EHTAH的左血泵和电液执行器组成的，并配有体积补偿室。系统重量为1160克。该系统最大流量为8.8 L/分钟，最大效率为14.2%。系统植入3头小牛，体重61公斤。其中一个活了90天。心输出量估计值为4 L/分钟。这些结果表明EHVAD系统有可能成为一种完全可植入的系统。经皮能量转移系统(TETS)、经皮光学遥测系统(TTS)和内部电池已经开发出来。在动物实验中使用电液压全人工心脏(EHTAH)系统对系统性能进行评估。在大约21 W输入功率的正常工作期间，该系统由TET驱动。该系统还按照规定的协议，每天由内部电池驱动。在放电40分钟的情况下，内部电池充满电3小时。TET的DC-DC传输效率保持在近85%。驱动参数通过皮肤以9600 bps的速度传输。我们为电液压人工心脏系统的优化驱动开发了一种新的泵隔膜位置监测方法。泵单元包括聚氨酯制造的隔膜式血泵和一个能量转换器，该转换器往复运动并将液压硅油输送到备用血泵。两个直径2.4 mm的超声晶体固定在泵壳的两侧，最大冲程轴长50 mm。超声波通过血腔、横隔膜和油腔传播。由于血液传播速度154m/S和硅油传播速度908m/S不同，超声波的传播时间随隔膜位置的不同而变化，传播时间与溢流式模拟循环试验中观察到的驱动油压力波形成的隔膜位置成正比。在完全弹出和完全填充状态下，传播时间分别达到最大值0.054 ms和最小值0.033 ms。在1~9 L/min范围内，心输出量与传播时间变化乘以心率的乘积呈线性关系。相关系数r=0.97。这些结果表明，在没有流量计的情况下，通过传播时间来检测横隔膜的位置，通过传播时间的变化来计算心输出量。我们还开发了用于植入性人工器官解剖拟合研究的计算机仿真系统。根据人体CT扫描图像重建了胸腔的三维图像。在移除脑室后，将泵单元植入并连接到计算机模型上的心房和血管，以决定合适的设计和安装。对于植入VAD或TAH系统的患者来说，眼袋感染是一个严重的主要问题。为了减少这种类型感染的风险，合理的方法是在设备的外表面涂上与组织相容的软材料，以减轻设备的机械振动和刚性设备与周围组织之间的应力。我们开发了一种新型的多孔器件-涂层材料，具有良好的组织相容性。这种材料由具有3D网状结构的链段聚氨酯组成，具有组织状的柔韧性和足够的机械强度。测试材料被装在硅胶管中，然后植入成年山羊的皮下组织。植入1年后，在浸润性组织中没有观察到炎性或坏死灶，从而表明有足够的组织生长到材料中形成紧密的相互连接。综上所述，该材料有望成为一种适用于植入型人工心脏的外表面涂层材料。较少

项目成果

Morphologicak change of the arterial system in the kidney under prolonged continuous flow left heart bypass

左心旁路长时间连续血流下肾动脉系统的形态变化

• 发表时间: 2002
• 期刊: J Artif Organs. Vol.26, No.11
• 作者: Hiroyuki Ohnishi;Tsuyoshi Itoh;Tomohiro Nishinaka;Eisuke Tatsumi;Toshihide Fukuda;Mitsuo Oshikawa;Kyoko Shioya;Tomonori Tsukiya;Yoshiaki Takewa;Akihiko Homma;Kunihiro Uesho;Koichi Sato;Hisateru Takano;Yoshiaki Taenaka
• 通讯作者: Yoshiaki Taenaka

A new monitoring method of diaphragm positions of an artificial heart with ultrasound techniques

一种利用超声技术监测人造心脏隔膜位置的新方法

• 发表时间: 2002
• 期刊: ASAIO Journal. Vol.48, No.2
• 作者: A.Homma;T.Kamimura;Y.Kakuta;E.Tatsumi;H.Takano;M.Nakamura;Y.Fukui;Y.Taenaka
• 通讯作者: Y.Taenaka

本間章彦, 和久井秀樹, 虫鹿貞彦, 巽英介, 西中知博, 大西裕幸, 武輪能明 他: "空気駆動方式補助人工心臓装着患者のQOL向上を目的とした携帯型駆動装置の開発"生体医工学,第41巻特別号,第42回日本エム・イー学会大会抄録・論文集. Vol.41 Suppl.. 557 (2003)

Akihiko Honma、Hideki Wakui、Sadahiko Mushika、Eisuke Tatsumi、Tomohiro Nishinaka、Hiroyuki Onishi、Yoshiaki Muwa 等人：“开发便携式驱动装置，旨在提高装有气动心室辅助装置的患者的生活质量”工程学，第 41 卷特刊，第 42 届日本 MEE 学会会议摘要和论文，第 41 卷增刊.. 557 (2003)

T.Nishinaka, E.tatsumi, Y Taenaka, N.Katagiri, H.Ohnishi, et al.: "A Newly Developed Anti-Thrombogenic Coating (TNC) and Application to VAD and An ECMO System"ASAIO Journal. Vol.48,No.2. 170 (2002)

T.Nishinaka、E.tatsumi、Y Taenaka、N.Katagiri、H.Ohnishi 等人：“新开发的抗血栓形成涂层 (TNC) 及其在 VAD 和 ECMO 系统中的应用”ASAIO 杂志。

Development of the direct electromagnetic ventricular assist device : First trial on ex vivo evaluation

直接电磁心室辅助装置的开发：首次离体评估试验

• 发表时间: 2004
• 期刊: ASAIO Journal. Vol.50, No.2
• 作者: K.Fukunaga;A.Homma;A.Funakubo;H.Sumikura;K.Onuma;M.Oshikawa;Y.Naito;E.Tatsumi;Y.Taenaka;S.Kitamura;Y.Fukui
• 通讯作者: Y.Fukui