Abstract:
:Hemodynamic control of left ventricular assist devices (LVADs) is generally a complicated problem due to diverse operating environments and the variability of the patients: both the changes in the circulatory and metabolic parameters as well as disturbances that require adjustment to the operating point. This challenge is especially acute with control of turbodynamic blood pumps. This article presents a pulsatility ratio controller for LVAD that provides a proper perfusion according to the physiological demands of the patient, while avoiding adverse conditions. It utilizes the pulsatility ratio of the flow through the pump and pressure difference across the pump as a control index and adjusts the pump speed according to the reference pulsatility ratio under the different operating conditions. The simulation studies were performed to evaluate the controller in consideration of the sensitivity to afterload and preload, influence of the contractility, and effect of suction sensitivity. The controller successfully adjusts the pump speed according to the reference pulsatility ratio, and supports the natural heart under diverse pump operating conditions. The resulting safe pump operations demonstrate the solid performance of the controller in terms of sensitivity to afterload and preload, influence of the contractility, and effect of suction sensitivity.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Choi S,Boston JR,Antaki JFdoi
10.1111/j.1525-1594.2007.00350.xsubject
Has Abstractpub_date
2007-02-01 00:00:00pages
114-25issue
2eissn
0160-564Xissn
1525-1594pii
AOR350journal_volume
31pub_type
杂志文章abstract::In total, 30 patients suffering from familial hypercholesterolemia, resistant to diet and lipid-lowering drugs, were treated for up to 6 years (3.6 + or - 1.6; range, 0.2-6.8 years) with low-density lipoprotein (LDL) apheresis. Three different systems were used; the dextran sulfate adsorption system (Kaneka) for 27 of...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1111/j.1525-1594.1996.tb04455.x
更新日期:1996-04-01 00:00:00
abstract::Temporary and immediately usable vascular access is a vital need in treating uremic patients. Subclavian vein cannulation, although a major progress, has been associated with significant morbidity and mortality. Accordingly, for the last 2.5 years the authors have been developing an alternative technique consisting of...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1986.tb02587.x
更新日期:1986-10-01 00:00:00
abstract::This study introduces a newly developed method for the formation of a stationary phase superficially embedded with immunoadsorbent, that is partially incomplete two-stage polymerization of acrylamide. Preliminary experimental studies show that binding activity of the immunoadsorbent was satisfactorily maintained after...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2005.29071.x
更新日期:2005-05-01 00:00:00
abstract::This study demonstrates in a novel way how volume and shape are restored to denervated degenerated muscles due to a special pattern of electrical stimulation. To this purpose, Spiral Computer Tomography (CT) and special image processing tools were used to develop a method to isolate the rectus femoris from other muscl...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2008.00610.x
更新日期:2008-08-01 00:00:00
abstract::Extracorporeal human lymphatic organs are expected to be excellent tools in the study of human molecular and cellular bases of the immunologic balance and tissue harmony. A rational approach and process to design a device and a procedure to recreate the human lymph node environment in vitro is described with emphasis ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2006.00303.x
更新日期:2006-10-01 00:00:00
abstract::We studied 22 patients with residual pulmonary hypertension or symptoms of postoperative pulmonary hypertensive crisis. They received low-dose inhalation (10 ppm) of nitric oxide (NO), a selective pulmonary vasodilator, after total correction for congenital heart anomalies. Fifteen minutes of NO inhalation improved th...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1111/j.1525-1594.1997.tb00692.x
更新日期:1997-01-01 00:00:00
abstract::A galactosamine-induced fulminant hepatic failure (FHF) rat model was used to study the effects of homologous cross-circulation and in situ liver perfusion. Cross-circulation with homologous donors did not significantly improve the survival time or recovery rate of grade II hepatic coma rats. Homologous in situ liver ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1980.tb03929.x
更新日期:1980-08-01 00:00:00
abstract::It has been speculated that testosterone stimulates erythropoiesis. We hypothesized that hemoglobin levels in hemodialysis (HD) patients are associated with serum testosterone concentrations. Testosterone, hemoglobin, and other biochemical parameters were measured in a representative sample of 98 chronic HD patients (...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12218
更新日期:2014-07-01 00:00:00
abstract::The objectives of this study were: (i) to evaluate the effects of perfusion modes (pulsatile vs. nonpulsatile) on vital organs recovery and (ii) to investigate the influences of two different perfusion modes on the homeostasis of thyroid hormones in pediatric patients undergoing cardiopulmonary bypass (CPB) procedures...
journal_title:Artificial organs
pub_type: 杂志文章,随机对照试验
doi:10.1111/j.1525-1594.2010.01159.x
更新日期:2010-11-01 00:00:00
abstract::Possible routes for water and salt flow and the most likely theories that describe coupling between water and salt flow across leaky epithelia are presented. The osmotic theories seem the most likely ones. However, several of the theories have weaknesses that render them unsatisfactory, in particular because of the po...
journal_title:Artificial organs
pub_type: 杂志文章,评审
doi:10.1111/j.1525-1594.1987.tb02713.x
更新日期:1987-12-01 00:00:00
abstract::Plasma procoagulant activities of factors XII, XI, IX, and VIII and plasma concentrations of factor XII antigen and high molecular weight kininogen (HMK) were determined in nine men with chronic renal failure (CRF) associated with long-standing spinal cord injury (SCI) treated with hemodialysis. The results were compa...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1985.tb04366.x
更新日期:1985-05-01 00:00:00
abstract::The most common method of controlling acidemia during lung-protective ventilation is CO₂ removal with an extracorporeal lung assist (ECLA) system. Another possibility to prevent acidemia is based on intravenous (i.v.) application of tris-hydroxymethyl-aminomethane (3 mol/L, THAM) buffer, which can bind hydrogen proton...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2011.01204.x
更新日期:2011-06-01 00:00:00
abstract::Aseptic loosening is the major cause of failure of hip implants after total hip arthroplasty. Stress shielding of the femur is known to be the principal factor involved in the aseptic loosening of hip implants. Solid stems are found to have a greater rigidity; therefore, they transfer less load proximally, which resul...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2010.01145.x
更新日期:2011-06-01 00:00:00
abstract::This article describes two ongoing numerical studies of fluid-structure interaction in the cardiovascular system: an idealized pulsatile ventricular assist device (VAD), consisting of two fluid chambers separated by a flexible diaphragm; and blood flow and heart wall motion during passive filling of a canine heart. Si...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2008.00644.x
更新日期:2008-11-01 00:00:00
abstract::What the most causative factor affecting hemolysis is still controversial. To resolve this problem, we investigated the relationship between hemolysis and heat generation in six types of centrifugal blood pumps (Bio-Pump, Delphin, Capiox, Nikkiso, Isoflow, and Toyobo). The analyzed parameters were index of hemolysis i...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1995.tb02453.x
更新日期:1995-09-01 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::Patients with end-stage renal disease have a very high prevalence and extent of arterial calcification. A number of studies suggest that similar pathophysiologic mechanisms are responsible for development and progression of calcification of atherosclerotic plaque and bone formation. Fetuin-A is a potent calcification ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00814.x
更新日期:2009-10-01 00:00:00
abstract::Rotary ventricular assist devices (VADs) are primarily used during surgery and short-term postoperative assistance. There are issues involving the use of rotary VADs including the behavior of flow emanating from the assist device which might induce flow irregularities that could potentially lead to stroke or cerebrova...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.06931_4.x
更新日期:2002-08-01 00:00:00
abstract::Ligament reconstruction using a tissue-engineered artificial ligament (TEAL) requires regeneration of the ligament-bone junction such that fixation devices such as screws and end buttons do not have to be used. The objective of this study was to develop a TEAL consisting of elastin-coated polydioxanone (PDS) sutures c...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13124
更新日期:2018-07-01 00:00:00
abstract::The generation of anaphylatoxins, particularly C5a, is important in extracorporeal circulation therapies such as granulocyte/monocyte apheresis, which activates the complement system and elevates C5a levels. However, no side effects of granulocyte/monocyte apheresis using cellulose acetate beads have been reported. To...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00995.x
更新日期:2010-12-01 00:00:00
abstract::Polynitroxylated pegylated hemoglobin (PNPH) as a multifunctional therapeutic takes advantage of the ability of hemoglobin (Hb) to transport oxygen, the antioxidative stress activities from the redox coupling of nitroxide and heme iron, and the hypercolloid properties of pegylation. The published preclinical data demo...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2011.01307.x
更新日期:2012-02-01 00:00:00
abstract::Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery press...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12277
更新日期:2014-11-01 00:00:00
abstract::In this study, a detection algorithm for suction and regurgitation of the centrifugal pump during left heart bypass without relying on external flow or pressure sensors was developed and evaluated in acute studies using adult goats. The detection scheme relies on power spectral density (PSD) analysis of the motor curr...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.1999.06397.x
更新日期:1999-06-01 00:00:00
abstract::The optimization of the monomer composition, using a polymerization kinetic study and the mechanical behavior study of the composites, was the principal objective of this work. The monomeric mixture analyzed is a part of the composite that has been in development at the University of Campinas, Brazil. Parameters such ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.07250.x
更新日期:2003-05-01 00:00:00
abstract::The blood pressure changes induced by the intra-aortic balloon pump (IABP) are expected to create clinical improvement in terms of coronary perfusion and myocardial oxygen consumption. However, the measured effects reported in literature are inconsistent. The aim of this study was to investigate the influence of ische...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12470
更新日期:2015-11-01 00:00:00
abstract::With the incidence of end-stage heart failure steadily increasing, the need for a practical total artificial heart (TAH) has never been greater. Continuous flow TAHs (CFTAH) are being developed using rotary blood pumps (RBPs), leveraging their small size, mechanical simplicity, and excellent durability. To completely ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13631
更新日期:2020-06-01 00:00:00
abstract::To expand the usage of the centrifugal pump (CP) in open heart surgery, we performed two studies. In the first, we evaluated pulsatile flow in the CP. In vitro pump performance of the Terumo Capiox pump (TCP) and the Sarns Delphin pump (SDP) and increase of free hemoglobin (mg/dl) after driving 6 h were investigated u...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1994.tb03393.x
更新日期:1994-09-01 00:00:00
abstract::Features of the human spinal cord motor control are described using two spinal cord injury models: (i) the spinal cord completely separated from brain motor structures by accidental injury; (ii) the spinal cord receiving reduced and altered supraspinal input due to an incomplete lesion. Systematic studies using surfac...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2005.29038.x
更新日期:2005-03-01 00:00:00
abstract::We have studied the cardiac beat synchronization (CBS) control for a rotary blood pump (RBP) and revealed that it can promote pulsatility and reduce cardiac load. Besides, patients with LVAD support sometimes suffer from aortic and mitral regurgitation (AR and MR). A control method for the RBP should be validated in w...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13795
更新日期:2020-08-19 00:00:00
abstract::We assessed the relationship of certain clinical variables (including bradykinin [BK] release and dialysis membrane) to initial mean arterial pressure (MAP) reduction in 47 patients requiring continuous renal replacement therapy (CRRT) in an intensive care unit. The pretreatment MAP was 84 +/- 14 mm Hg for the group a...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2001.06703.x
更新日期:2001-12-01 00:00:00