Abstract:
:In previous studies, we presented main strategies for suspending the rotor of a mixed-flow type (centrifugal and axial) ventricular assist device (VAD), originally presented by the Institute Dante Pazzanese of Cardiology (IDPC), Brazil. Magnetic suspension is achieved by the use of a magnetic bearing architecture in which the active control is executed in only one degree of freedom, in the axial direction of the rotor. Remaining degrees of freedom, excepting the rotation, are restricted only by the attraction force between pairs of permanent magnets. This study is part of a joint project in development by IDPC and Escola Politecnica of São Paulo University, Brazil. This article shows advances in that project, presenting two promising solutions for magnetic bearings. One solution uses hybrid cores as electromagnetic actuators, that is, cores that combine iron and permanent magnets. The other solution uses actuators, also of hybrid type, but with the magnetic circuit closed by an iron core. After preliminary analysis, a pump prototype has been developed for each solution and has been tested. For each prototype, a brushless DC motor has been developed as the rotor driver. Each solution was evaluated by in vitro experiments and guidelines are extracted for future improvements. Tests have shown good results and demonstrated that one solution is not isolated from the other. One complements the other for the development of a single-axis-controlled, hybrid-type magnetic bearing for a mixed-flow type VAD.
journal_name
Artif Organsjournal_title
Artificial organsauthors
da Silva I,Horikawa O,Cardoso JR,Camargo FA,Andrade AJ,Bock EGdoi
10.1111/j.1525-1594.2011.01265.xsubject
Has Abstractpub_date
2011-05-01 00:00:00pages
448-53issue
5eissn
0160-564Xissn
1525-1594journal_volume
35pub_type
杂志文章,多中心研究abstract::Testing failed to detect free isocyanates in dialyzer rinses or significant levels of immunoglobulin E antibodies to isocyanate-protein conjugates in the serum of individuals reacting during hemodialysis with dialyzers containing Cuprophan membranes. Extended immunization of rabbits with Limulus lysate-reactive materi...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1984.tb04298.x
更新日期:1984-08-01 00:00:00
abstract::Current hemodialysis treatment is insufficient because of intermittent treatment and loss of tubular function. In order to overcome the loss of tubular function, a bioartificial kidney has been developed consisting of continuous hemofiltration (CHF) with 10 L/day of filtrate and a bioartificial tubule device using pro...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1111/j.1525-1594.2004.07323.x
更新日期:2004-01-01 00:00:00
abstract::Twelve patients, 8 male and 4 female, aged from 26 to 70 years were studied. They were on hemodialysis (HD) 4 h three times weekly with cuprophan hollow fiber dialyzers (Gambro 120M) and dialysate containing 35 mEq/L of acetate. The study compares two random HD sessions on each patient. Sixty minutes prior to one rand...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1989-10-01 00:00:00
abstract::Solute clearance during high-flux hemodialysis is determined by the combined effects of solute convection and diffusion in the membrane, blood, and dialysate. Previous studies have focused almost entirely on the membrane transport phenomena, largely ignoring the potential contribution from bulk mass transport across t...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1993.tb00403.x
更新日期:1993-11-01 00:00:00
abstract::Transcatheter aortic valve implantation (TAVI) has gained considerable acceptance in the past decade due to its lower risks than conventional open-heart surgery. However, the deformation and delamination of the leaflets during the crimping procedure have raised questions about the durability and long-term serviceabili...
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:10.1111/j.1525-1594.2009.00772.x
更新日期:2010-02-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1996.tb04473.x
更新日期:1996-05-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2001.025001053.x
更新日期:2001-01-01 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: 临床试验,杂志文章
doi:10.1111/j.1525-1594.1996.tb04573.x
更新日期:1996-08-01 00:00:00
abstract::A pseudo-one compartment model has been proposed to describe phosphorus kinetics during hemodialysis and the immediate post-dialysis period. This model assumes that phosphorus mobilization from tissues is proportional to the difference between the pre-dialysis serum concentration (a constant) and the instantaneous ser...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12897
更新日期:2017-11-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2007.00421.x
更新日期:2007-07-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2005.29057.x
更新日期:2005-04-01 00:00:00
abstract::There is an increasing need for research and development centers to deal with design and evaluation of organ replacement systems, the improvement of older devices, and the study of biocompatibility problems. Special attention, in this article, is focused on the determinant role of the background of the investigators i...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1989.tb01579.x
更新日期:1989-12-01 00:00:00
abstract::Extracorporeal life support (ECLS) has been increasingly utilized to manage cardiac and pulmonary dysfunction. The impact of obesity on outcomes of ECLS is poorly defined. The purpose of the study was to compare in-hospital mortality, resource use, complications, and readmissions in obese versus non-obese patients rec...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13752
更新日期:2020-11-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract::The effectiveness of the blood substitute neo red cells (NRC) on hemorrhagic shock was evaluated in dogs. Shock was induced by bloodletting, and NRC was infused immediately until the dogs recovered from shock; the process was repeated 3 times (mild shock), or NRC was infused after shock was maintained for 30 min, and ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::Continuous and intermittent high shear were loaded to red blood cells in a cone and a plate rheoscope. The mechanical damage to red cells was compared for continuous and intermittent shear. The intermittent shear was achieved by alternately starting and stopping shear repeatedly. In the case of intermittent shear load...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2007.00408.x
更新日期:2007-06-01 00:00:00
abstract::Capillary membrane filters are devices commonly used for plasmapheresis and recirculating detoxification systems, including plasmaseparation units. Besides clinical trials and case reports, research on plasmafiltration techniques is carried out using in vitro systems. Notably, such hemoperfused in vitro systems requir...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.07132.x
更新日期:2003-07-01 00:00:00
abstract::Modeling different treatment options before a procedure is performed is a promising approach for surgical decision making and patient care in heart valve disease. This study investigated the hemodynamic impact of different prostheses through patient-specific MRI-based CFD simulations. Ten time-resolved MRI data sets w...
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
abstract::Ventricular assist devices have been shown to be effective in advanced heart failure selected patients. They often have borderline end-organ function, what facilitates organ dysfunction. Liver failure is difficult to manage and leads to increased morbidity and mortality. We report a case of ductular cholestasis, an un...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00760.x
更新日期:2010-02-01 00:00:00
abstract::In this proof of principle study, we investigated the effectiveness and safety of hemodynamic support with the Intra-Ventricular Membrane Pump (IVMP). The IVMP was implanted into the apex of the left ventricle. Hemodynamic assessment was performed in six ex vivo beating porcine hearts (PhysioHeart platform). The cardi...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13757
更新日期:2020-12-01 00:00:00
abstract::Although several left ventricular assist devices (LVADs) have been used widely, remote monitoring of LVAD parameters has been available only recently. We present our remote monitoring experience with an axial-flow LVAD (HeartAssist-5, MicroMed Cardiovascular, Inc., Houston, TX, USA). Five consecutive patients who were...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12144
更新日期:2013-09-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2008.00688.x
更新日期:2008-12-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.07015.x
更新日期:2003-03-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.1999.06258.x
更新日期:1999-04-01 00:00:00
abstract::To develop an effective hybrid bioartificial liver (BAL) device, the material of the scaffold is very important to support hepatocytes that have both growth ability and hepatic differentiated functions. In this study we used paper (Kimwipe, Kimberly-Clark Corp., Roswell, GA, U.S.A.) as a scaffold. Primary hepatocytes ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2000.06506.x
更新日期:2000-04-01 00:00:00
abstract::Centrifugal pumps have been used widely as the main pump in open heart surgery to reduce damage to blood elements and to reduce the activation of the coagulation system. The purpose of this study was the evaluation and comparison of the effects of two types of centrifugal pumps and of one type of roller pump on blood ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1996.tb04507.x
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13270
更新日期:2019-01-01 00:00:00
abstract::This article reports preliminary results of pilot studies of a new implantable two channel drop foot stimulator. The stimulator consists of an externally worn transmitter inductively coupled to an implanted receiver unit located in the lower leg, lateral and distal to the knee. The receiver is connected to electrodes ...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1046/j.1525-1594.2002.06949.x
更新日期:2002-03-01 00:00:00