The Experts below are selected from a list of 147 Experts worldwide ranked by ideXlab platform

K. Kamiya - One of the best experts on this subject based on the ideXlab platform.

  • EMBC - Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2–3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

  • Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

Y. Shiraishi - One of the best experts on this subject based on the ideXlab platform.

  • Peristaltic hemodynamics of a new pediatric Circulatory Assist system for Fontan circulation using shape memory alloy fibers
    2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. Yambe, M. H. Omran, T. Shiga, Hidekazu Miura, Y. Tsuboko, D. Homma, M. Yamagishi
    Abstract:

    Fontan procedure is one of the common surgical treatments of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. We have been developing a pulmonary Circulatory Assist Device using shape memory alloy fibers for Fontan circulation with total cavopulmonary connection. It consisted of the shape memory alloy fibers, the diameter of which are 100 μm. The fibers could wrap the ePTFE conduit for Fontan TCPC connection from the outside. We designed the sequential motion control system for sophisticated pulmonary hemodynamics by the pulsatile flow generation. In order to achieve pulsatile flow Assistance in pulmonary arterial system, we fabricated a mechanical structure by sequential contraction of shape memory alloy fibers. Then, we developed a sequential contraction controller for the Assist system, which could reproduce the wall contractile velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock Circulatory system, which consisted of two overflow tanks representing venous and pulmonary arterial pressures in Fontan circulation. As a result, the pulmonary circulation Assist Device with sequential contraction could achieve effective promotion of the pulsatility in pulmonary arterial flow.

  • Preliminary Design of the Mechanical Circulation Assist Device for Fontan Circulation using Shape Memory Alloy Fibers
    IFMBE Proceedings, 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. K. Sugai, T. Shiga, Yusuke Tsuboko, Hidekazu Miura, Mohamed O. Hashem, Chihiro Koga, Hiroyuki Hashimoto, T. Yambe
    Abstract:

    Fontan procedure is one of the common surgical treatment of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. Pulmonary blood flow in the Fontan circulation is lower than in healthy subjects, and the central venous pressure may elevate. In this study, we developed a mechanical Circulatory Assist Device for the extracardiac conduit for Fontan circulation and examined its driving method in the mock pediatric pulmonary Circulatory system. We used shape memory alloy (SMA) fiber as an actuator of the Device. The SMA actuator wrapped the extracardiac conduit between inferior vena cava and pulmonary artery. We designed two different types of the Circulatory Assist Devices. We drove these Devices in two different modes by the synchronized and sequential motions. The flow volume was 10mL/min against a load of 10mmHg, and the maximum contractile force indicated 60mmHg in the mock test. These results suggested the effective mechanical Assistance for Fontan pulmonary circulation.

  • EMBC - Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2–3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

  • Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

T. Yambe - One of the best experts on this subject based on the ideXlab platform.

  • sophisticated hydrodynamic simulation of pulmonary circulation for the preclinical examination of right heart Circulatory Assist Device
    World Congress on Medical Physics and Biomedical Engineering WC 2018, 2019
    Co-Authors: Yusuke Tsuboko, A. Yamada, Yasuyuki Shiraishi, Kiyotaka Iwasaki, Mitsuo Umezu, T. Yambe
    Abstract:

    To evaluate systemic Circulatory support Devices such as left ventricular Assist system, surgical heart valve prosthesis, and transcatheter aortic valve, various in vitro hydrodynamic tests have been performed. As these Devices are being applied to the pulmonary Circulatory support in recent years, novel evaluation platform for right heart support is increasingly demanded. This study aims to develop a pulmonary mechanical Circulatory simulation system to assess the hydrodynamic performance of newly designed artificial cardiovascular Devices. For the construction of the system, we developed the pneumatically-driven polymer right atrial and ventricular models with the pulmonary arterial valve chamber, silicone-made peripheral pulmonary artery model, and a venous reservoir. A woven polyester vascular graft and commercially available mechanical bileaflet valve were installed into the valve chamber. Then, the right ventricular pressure and pulmonary arterial pressure were regulated by the peripheral resistive unit. As a result, we successfully obtained the standard conditions of our mechanical Circulatory system to be 28/3 (systolic/diastolic) mmHg of right ventricular pressure, 29/7 mmHg of pulmonary arterial pressure, 6 mmHg of mean right atrial pressure, and 3.0 L/min of pulmonary flow rate. To carry out the sophisticated assessment for the support of the pulmonary surgical and percutaneous treatments, we are preparing the next step with the reproduction of respiratory changes in pulmonary peripheral resistance, and the patient-specific shape vascular model including catheter access vessels. Under the highly simulated both pulmonary anatomical morphology and hemodynamic function conditions, effective preclinical examination of newly designed surgical or percutaneous pulmonary Circulatory support Devices can be performed.

  • Peristaltic hemodynamics of a new pediatric Circulatory Assist system for Fontan circulation using shape memory alloy fibers
    2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. Yambe, M. H. Omran, T. Shiga, Hidekazu Miura, Y. Tsuboko, D. Homma, M. Yamagishi
    Abstract:

    Fontan procedure is one of the common surgical treatments of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. We have been developing a pulmonary Circulatory Assist Device using shape memory alloy fibers for Fontan circulation with total cavopulmonary connection. It consisted of the shape memory alloy fibers, the diameter of which are 100 μm. The fibers could wrap the ePTFE conduit for Fontan TCPC connection from the outside. We designed the sequential motion control system for sophisticated pulmonary hemodynamics by the pulsatile flow generation. In order to achieve pulsatile flow Assistance in pulmonary arterial system, we fabricated a mechanical structure by sequential contraction of shape memory alloy fibers. Then, we developed a sequential contraction controller for the Assist system, which could reproduce the wall contractile velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock Circulatory system, which consisted of two overflow tanks representing venous and pulmonary arterial pressures in Fontan circulation. As a result, the pulmonary circulation Assist Device with sequential contraction could achieve effective promotion of the pulsatility in pulmonary arterial flow.

  • Preliminary Design of the Mechanical Circulation Assist Device for Fontan Circulation using Shape Memory Alloy Fibers
    IFMBE Proceedings, 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. K. Sugai, T. Shiga, Yusuke Tsuboko, Hidekazu Miura, Mohamed O. Hashem, Chihiro Koga, Hiroyuki Hashimoto, T. Yambe
    Abstract:

    Fontan procedure is one of the common surgical treatment of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. Pulmonary blood flow in the Fontan circulation is lower than in healthy subjects, and the central venous pressure may elevate. In this study, we developed a mechanical Circulatory Assist Device for the extracardiac conduit for Fontan circulation and examined its driving method in the mock pediatric pulmonary Circulatory system. We used shape memory alloy (SMA) fiber as an actuator of the Device. The SMA actuator wrapped the extracardiac conduit between inferior vena cava and pulmonary artery. We designed two different types of the Circulatory Assist Devices. We drove these Devices in two different modes by the synchronized and sequential motions. The flow volume was 10mL/min against a load of 10mmHg, and the maximum contractile force indicated 60mmHg in the mock test. These results suggested the effective mechanical Assistance for Fontan pulmonary circulation.

  • EMBC - Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2–3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

  • Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

A. Yamada - One of the best experts on this subject based on the ideXlab platform.

  • sophisticated hydrodynamic simulation of pulmonary circulation for the preclinical examination of right heart Circulatory Assist Device
    World Congress on Medical Physics and Biomedical Engineering WC 2018, 2019
    Co-Authors: Yusuke Tsuboko, A. Yamada, Yasuyuki Shiraishi, Kiyotaka Iwasaki, Mitsuo Umezu, T. Yambe
    Abstract:

    To evaluate systemic Circulatory support Devices such as left ventricular Assist system, surgical heart valve prosthesis, and transcatheter aortic valve, various in vitro hydrodynamic tests have been performed. As these Devices are being applied to the pulmonary Circulatory support in recent years, novel evaluation platform for right heart support is increasingly demanded. This study aims to develop a pulmonary mechanical Circulatory simulation system to assess the hydrodynamic performance of newly designed artificial cardiovascular Devices. For the construction of the system, we developed the pneumatically-driven polymer right atrial and ventricular models with the pulmonary arterial valve chamber, silicone-made peripheral pulmonary artery model, and a venous reservoir. A woven polyester vascular graft and commercially available mechanical bileaflet valve were installed into the valve chamber. Then, the right ventricular pressure and pulmonary arterial pressure were regulated by the peripheral resistive unit. As a result, we successfully obtained the standard conditions of our mechanical Circulatory system to be 28/3 (systolic/diastolic) mmHg of right ventricular pressure, 29/7 mmHg of pulmonary arterial pressure, 6 mmHg of mean right atrial pressure, and 3.0 L/min of pulmonary flow rate. To carry out the sophisticated assessment for the support of the pulmonary surgical and percutaneous treatments, we are preparing the next step with the reproduction of respiratory changes in pulmonary peripheral resistance, and the patient-specific shape vascular model including catheter access vessels. Under the highly simulated both pulmonary anatomical morphology and hemodynamic function conditions, effective preclinical examination of newly designed surgical or percutaneous pulmonary Circulatory support Devices can be performed.

  • Peristaltic hemodynamics of a new pediatric Circulatory Assist system for Fontan circulation using shape memory alloy fibers
    2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. Yambe, M. H. Omran, T. Shiga, Hidekazu Miura, Y. Tsuboko, D. Homma, M. Yamagishi
    Abstract:

    Fontan procedure is one of the common surgical treatments of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. We have been developing a pulmonary Circulatory Assist Device using shape memory alloy fibers for Fontan circulation with total cavopulmonary connection. It consisted of the shape memory alloy fibers, the diameter of which are 100 μm. The fibers could wrap the ePTFE conduit for Fontan TCPC connection from the outside. We designed the sequential motion control system for sophisticated pulmonary hemodynamics by the pulsatile flow generation. In order to achieve pulsatile flow Assistance in pulmonary arterial system, we fabricated a mechanical structure by sequential contraction of shape memory alloy fibers. Then, we developed a sequential contraction controller for the Assist system, which could reproduce the wall contractile velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock Circulatory system, which consisted of two overflow tanks representing venous and pulmonary arterial pressures in Fontan circulation. As a result, the pulmonary circulation Assist Device with sequential contraction could achieve effective promotion of the pulsatility in pulmonary arterial flow.

  • Preliminary Design of the Mechanical Circulation Assist Device for Fontan Circulation using Shape Memory Alloy Fibers
    IFMBE Proceedings, 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. K. Sugai, T. Shiga, Yusuke Tsuboko, Hidekazu Miura, Mohamed O. Hashem, Chihiro Koga, Hiroyuki Hashimoto, T. Yambe
    Abstract:

    Fontan procedure is one of the common surgical treatment of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. Pulmonary blood flow in the Fontan circulation is lower than in healthy subjects, and the central venous pressure may elevate. In this study, we developed a mechanical Circulatory Assist Device for the extracardiac conduit for Fontan circulation and examined its driving method in the mock pediatric pulmonary Circulatory system. We used shape memory alloy (SMA) fiber as an actuator of the Device. The SMA actuator wrapped the extracardiac conduit between inferior vena cava and pulmonary artery. We designed two different types of the Circulatory Assist Devices. We drove these Devices in two different modes by the synchronized and sequential motions. The flow volume was 10mL/min against a load of 10mmHg, and the maximum contractile force indicated 60mmHg in the mock test. These results suggested the effective mechanical Assistance for Fontan pulmonary circulation.

  • EMBC - Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2–3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

  • Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

T. Shiga - One of the best experts on this subject based on the ideXlab platform.

  • Peristaltic hemodynamics of a new pediatric Circulatory Assist system for Fontan circulation using shape memory alloy fibers
    2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. Yambe, M. H. Omran, T. Shiga, Hidekazu Miura, Y. Tsuboko, D. Homma, M. Yamagishi
    Abstract:

    Fontan procedure is one of the common surgical treatments of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. We have been developing a pulmonary Circulatory Assist Device using shape memory alloy fibers for Fontan circulation with total cavopulmonary connection. It consisted of the shape memory alloy fibers, the diameter of which are 100 μm. The fibers could wrap the ePTFE conduit for Fontan TCPC connection from the outside. We designed the sequential motion control system for sophisticated pulmonary hemodynamics by the pulsatile flow generation. In order to achieve pulsatile flow Assistance in pulmonary arterial system, we fabricated a mechanical structure by sequential contraction of shape memory alloy fibers. Then, we developed a sequential contraction controller for the Assist system, which could reproduce the wall contractile velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock Circulatory system, which consisted of two overflow tanks representing venous and pulmonary arterial pressures in Fontan circulation. As a result, the pulmonary circulation Assist Device with sequential contraction could achieve effective promotion of the pulsatility in pulmonary arterial flow.

  • Preliminary Design of the Mechanical Circulation Assist Device for Fontan Circulation using Shape Memory Alloy Fibers
    IFMBE Proceedings, 2013
    Co-Authors: A. Yamada, Y. Shiraishi, T. K. Sugai, T. Shiga, Yusuke Tsuboko, Hidekazu Miura, Mohamed O. Hashem, Chihiro Koga, Hiroyuki Hashimoto, T. Yambe
    Abstract:

    Fontan procedure is one of the common surgical treatment of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. Pulmonary blood flow in the Fontan circulation is lower than in healthy subjects, and the central venous pressure may elevate. In this study, we developed a mechanical Circulatory Assist Device for the extracardiac conduit for Fontan circulation and examined its driving method in the mock pediatric pulmonary Circulatory system. We used shape memory alloy (SMA) fiber as an actuator of the Device. The SMA actuator wrapped the extracardiac conduit between inferior vena cava and pulmonary artery. We designed two different types of the Circulatory Assist Devices. We drove these Devices in two different modes by the synchronized and sequential motions. The flow volume was 10mL/min against a load of 10mmHg, and the maximum contractile force indicated 60mmHg in the mock test. These results suggested the effective mechanical Assistance for Fontan pulmonary circulation.

  • EMBC - Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2–3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.

  • Structural design of a newly developed pediatric Circulatory Assist Device for fontan circulation by using shape memory alloy fiber
    2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2011
    Co-Authors: Y. Shiraishi, T. K. Sugai, A. Tanaka, M. Yoshizawa, T. Yambe, A. Yamada, M. H. Omran, T. Shiga, T. Kitano, K. Kamiya
    Abstract:

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary Circulatory Assist Device by using shape memory alloy fibers. We developed a pulmonary Circulatory Assist Device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The Device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary Circulatory Assist Device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the Device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10mmHg loading.