Abstract:
:For the development of a totally implantable ventricular assist system (VAS), we have been developing the vibrating flow pump (VFP), which can generate oscillated blood flow with a relative high frequency (10-50 Hz) for a totally implantable system. In this study, the effects of left ventricular assistance with this unique oscillated blood flow were analyzed by the use of nonlinear mathematics for evaluation as the whole circulatory regulatory system, not as the decomposed parts of the system. Left heart bypasses using the VFP from the left atrium to the descending aorta were performed in chronic animal experiments using healthy adult goats. The ECG, arterial blood pressure, VFP pump flow, and the flow of the descending aorta were recorded in the data recorder during awake conditions and analyzed in a personal computer system through an A-D convertor. By the use of nonlinear mathematics, time series data were embedded into the phase space, the Lyapunov numerical method, fractal dimension analysis, and power spectrum analysis were performed to evaluate nonlinear dynamics. During left ventricular assistance with the VFP, Mayer wave fluctuations were decreased in the power spectrum, the fractal dimension of the hemodynamics was significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that nonlinear dynamics, which mediate the cardiovascular dynamics, may be affected during left ventricular (LV) bypass with oscillated flow. The decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased peripheral resistance. Decreased sympathetic discharges may be the origin of the decreased Mayer wave and fractal dimension. These nonlinear dynamic analyses may be useful to design optimal VAS control.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Nitta S,Yambe T,Kobayashi S,Hashimoto H,Yoshizawa M,Mastuki H,Tabayashi K,Takeda Hdoi
10.1046/j.1525-1594.1999.06288.xsubject
Has Abstractpub_date
1999-01-01 00:00:00pages
119-23issue
1eissn
0160-564Xissn
1525-1594journal_volume
23pub_type
杂志文章abstract::Inverse ratio ventilation (IRV) is a ventilatory technique that uses an inspiratory to expiratory ratio (I:E) greater than 1:1. We studied the effects of mechanical ventilation with an I:E of 1:3, 1:1, and 2:1 on arterial oxygenation in 10 patients with sepsis-associated acute respiratory distress syndrome (ARDS). At ...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:2000-11-01 00:00:00
abstract::Biomechanical actuation of an implanted ventricular assist device (VAD) is an attractive means of providing long-term circulatory support. Studies show that energy from electrically stimulated skeletal muscle can, in principle, be used to provide tether-free cardiac assistance without the need for percutaneous driveli...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2010.01170.x
更新日期:2011-07-01 00:00:00
abstract::The Fas molecule, also designated APO-1/CD95, belongs to the tumor necrosis factor (TNF) receptor family. It is a widely expressed membrane-anchored protein that induces apoptosis by Fas/Fas ligand (Fas-L) mediation. It was reported that Fas-mediated apoptosis plays an important role in regulation of the immune system...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2000.06591.x
更新日期:2000-08-01 00:00:00
abstract::Total hip arthroplasty (THA) can be achieved by using a cemented or noncemented prosthesis. Besides patient's age, weight, and other clinical signs, the evaluation of the quality of the bones is a crucial parameter on which orthopedic surgeons base the choice between cemented and noncemented THA. Although bone density...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12033
更新日期:2013-06-01 00:00:00
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journal_title:Artificial organs
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
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更新日期:1994-08-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12390
更新日期:2015-04-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13663
更新日期:2020-08-01 00:00:00
abstract::In this pilot study, we assessed the feasibility of using positron emission tomography (PET) imaging for in vivo measurement of skeletal muscle ventricle (SMV) tissue blood flow. In 4 dogs, with SMVs prepared from their latissimus dorsi muscle, we quantified SMV tissue blood flow by PET and related it to the tissue fl...
journal_title:Artificial organs
pub_type: 杂志文章
doi:
更新日期:2001-04-01 00:00:00
abstract::In 1976, the authors became the codevelopers of the first successful bileaflet heart valve which has become the standard in valvular surgery. However, there still remains a significant rate of thromboembolism and thrombosis which can be attributed to the inherent design of cavities in the pivot area. These cavities co...
journal_title:Artificial organs
pub_type: 杂志文章
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更新日期:2002-05-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2006.00322.x
更新日期:2006-12-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1978.tb03465.x
更新日期:1978-08-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13465
更新日期:2019-09-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12304
更新日期:2014-08-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12955
更新日期:2018-01-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2012.01561.x
更新日期:2013-03-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2010.01077.x
更新日期:2010-10-01 00:00:00
abstract::Bubble blood oxygenators equipped with baffles of various types in the oxygenating column were studied. The rate of hemolysis, the volumetric coefficient for oxygen absorption into blood, and the fractional gas holdup were found to be affected mainly by the superficial gas velocity. When compared with the conventional...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1979.tb01032.x
更新日期:1979-05-01 00:00:00
abstract::Continuous-flow left ventricular assist devices (LVADs) reduce peak systolic flow, increase diastolic flow, and eliminate pulsatility of circulation. Altered blood flow may lead to a change in end-organ perfusion. Analysis of the flow dynamics of the arteries of end organs, such as the brain, may indicate whether an o...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13616
更新日期:2020-05-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1988.tb01518.x
更新日期:1988-02-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
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更新日期:2009-09-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章,随机对照试验
doi:10.1111/j.1525-1594.2006.00275.x
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2003.07141.x
更新日期:2003-12-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13503
更新日期:2019-10-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.06798.x
更新日期:2002-01-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1996.tb04542.x
更新日期:1996-07-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2004.07284.x
更新日期:2004-06-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1995.tb02362.x
更新日期:1995-05-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.06981.x
更新日期:2003-08-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.1998.06015.x
更新日期:1998-09-01 00:00:00
abstract::An investigation has been made into whether charcoal hemoperfusion stimulates a hyperplastic response in the liver of the normal rat. Animals underwent hemoperfusion over Norit RBX1 (Strathclyde, Glasgow, U.K.) charcoal granules using a technique which allowed perfusion in the unrestrained and conscious state. Control...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1982.tb04080.x
更新日期:1982-05-01 00:00:00