DocumentCode :
2507418
Title :
Structural design of a newly developed pediatric circulatory assist device for fontan circulation by using shape memory alloy fiber
Author :
Shiraishi, Y. ; Sugai, T.K. ; Tanaka, A. ; Yoshizawa, M. ; Yambe, T. ; Yamada, A. ; Omran, M.H. ; Shiga, T. ; Kitano, T. ; Kamiya, K. ; Mochizuki, S. ; Miura, H. ; Homma, D. ; Yamagishi, M.
Author_Institution :
Inst. of Dev., Aging & Cancer, Tohoku Univ., Sendai, Japan
fYear :
2011
fDate :
Aug. 30 2011-Sept. 3 2011
Firstpage :
8353
Lastpage :
8355
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.
Keywords :
biomedical equipment; biomedical materials; blood vessels; cardiovascular system; diseases; medical computing; paediatrics; shape memory effects; surgery; Fontan algorithm; TCPC; congenital heart disease; contractile ratio; fontan circulation; frequency 2 Hz to 3 Hz; maximum contraction ratio; pediatric circulatory assist device; pediatric patients; pulmonary artery; pulmonary circulatory assist device; servo actuator; shape memory alloy fiber; structural design; surgical treatment; total cavopulmonary connection; ventricle; Actuators; Educational institutions; Heart; Loading; Optical fiber devices; Shape; Shape memory alloys; Alloys; Child; Equipment Design; Fontan Procedure; Heart-Assist Devices; Humans; Mechanical Phenomena; Pressure; Pulmonary Circulation;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Engineering in Medicine and Biology Society, EMBC, 2011 Annual International Conference of the IEEE
Conference_Location :
Boston, MA
ISSN :
1557-170X
Print_ISBN :
978-1-4244-4121-1
Electronic_ISBN :
1557-170X
Type :
conf
DOI :
10.1109/IEMBS.2011.6092060
Filename :
6092060
Link To Document :
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