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 with and without velocity encoding were obtained to reconstruct the aorta and set hemodynamic boundary conditions for simulations. Aortic hemodynamics after virtual valve replacement with a biological and mechanical valve prosthesis were investigated. Wall shear stress (WSS), secondary flow degree (SFD), transvalvular pressure drop (TPD), turbulent kinetic energy (TKE), and normalized flow displacement (NFD) were evaluated to characterize valve-induced hemodynamics. The biological prostheses induced significantly higher WSS (medians: 9.3 vs. 8.6 Pa, P = 0.027) and SFD (means: 0.78 vs. 0.49, P = 0.002) in the ascending aorta, TPD (medians: 11.4 vs. 2.7 mm Hg, P = 0.002), TKE (means: 400 vs. 283 cm2 /s2 , P = 0.037), and NFD (means: 0.0994 vs. 0.0607, P = 0.020) than the mechanical prostheses. The differences between the prosthesis types showed great inter-patient variability, however. Given this variability, a patient-specific evaluation is warranted. In conclusion, MRI-based CFD offers an opportunity to assess the interactions between prosthesis and patient-specific boundary conditions, which may help in optimizing surgical decision making and providing additional guidance to clinicians.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Hellmeier F,Nordmeyer S,Yevtushenko P,Bruening J,Berger F,Kuehne T,Goubergrits L,Kelm Mdoi
10.1111/aor.12955subject
Has Abstractpub_date
2018-01-01 00:00:00pages
49-57issue
1eissn
0160-564Xissn
1525-1594journal_volume
42pub_type
杂志文章abstract::This article reviews the clinical, biological, radiological, and pathological procedures and their respective indications for the practical diagnosis of the following various histological patterns of renal osteodystrophy: osteitis fibrosa due to parathyroid hormone (PTH) hypersecretion: osteomalacia or rickets due to ...
journal_title:Artificial organs
pub_type: 杂志文章,评审
doi:10.1046/j.1525-1594.1998.06198.x
更新日期:1998-07-01 00:00:00
abstract::Upon introducing off-pump coronary artery bypass grafting (CABG), the indications for CABG were expanded to include patients who previously had no operative indications. For accurate anastomosis, various devices and methods have been developed. Bradycardia is easily induced by drug administration. However, this method...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.07087.x
更新日期:2002-10-01 00:00:00
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 u...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.1999.06288.x
更新日期:1999-01-01 00:00:00
abstract::Ten dialysis patients were followed in a prospective study to determine the neurotoxicity of metabolites in the middle molecule (MM) molecular weight (mol wt) range of 500-200 daltons/molecule. In the absence of readily available direct serum measurements of MM concentrations, a theoretically calculated dialysis index...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1978.tb01002.x
更新日期:1978-02-01 00:00:00
abstract::The limited success of cardiac stem cell therapy has lately generated discussion regarding its effectiveness. We hypothesized that immediate cell loss after intramyocardial injection significantly obscures the regenerative potential of stem cell therapy. Therefore, our aim was to assess the distribution and quantity o...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12268
更新日期:2014-11-01 00:00:00
abstract::A centrifugal blood pump with a double pivot impeller and an eccentric inlet port is being developed as an implantable artificial heart by the Baylor College of Medicine and Miwatec Co. Ltd. Flow visualization measurements were conducted to compare the flow around the pivot for two impeller operational modes: the top ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2006.00155.x
更新日期:2006-01-01 00:00:00
abstract::Stimulation of different spinal cord segments in humans is a widely developed clinical practice for modification of pain, altered sensation, and movement. The human lumbar cord has become a target for modification of motor control by epidural and, more recently, by transcutaneous spinal cord stimulation. Posterior col...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2011.01213.x
更新日期:2011-03-01 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::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 Genius is a convenient single-pass batch hemodialysis system. Dialysate is heated during the preparation phase. Once the container is filled at one of the three available starting temperatures, dialysate cools spontaneously. As dialysate temperature plays an important role in hemodynamic stability, knowledge of th...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00981.x
更新日期:2010-12-01 00:00:00
abstract::By using high speed gel filtration combined with ion exchange gradient elution chromatography, the concentrations of plasma (p) middle molecules (MM) were determined in 126 samples from 90 non-dialyzed azotemic patients and in 210 pre-dialysis samples from 53 regular hemodialysis and 24 intermittent peritoneal dialysi...
journal_title:Artificial organs
pub_type: 杂志文章
doi:
更新日期:1981-01-01 00:00:00
abstract::Cardiac surgery with cardiopulmonary bypass is associated with a systemic inflammatory response syndrome. The major clinical features of this include a reduction of pulmonary compliance and increased extracellular fluids, with increased pulmonary shunt fraction similar to acute respiratory distress syndrome, thus resu...
journal_title:Artificial organs
pub_type: 杂志文章,随机对照试验
doi:10.1111/j.1525-1594.2009.00777.x
更新日期:2009-08-01 00:00:00
abstract::The DexAide right ventricular assist device (RVAD) has been developed to provide an implantable RVAD option to surgeons. The aim of this study was to determine the optimal cannula design and optimal implantation location of the DexAide RVAD in preparation for its clinical use. Separately, a HeartMate XVE left ventricu...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2007.00438.x
更新日期:2007-08-01 00:00:00
abstract::Bacillus Calmette-Guerin (BCG) has been shown to have therapeutic effects on asthma through CD4+CD25+ regulatory T cells (Tregs). We sought to assess pretreatment with inactivated BCG on CD4+CD25+ Tregs and its functional and structural effects in rat asthma model. The rat asthma model was established using ovalbumin ...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12566
更新日期:2016-04-01 00:00:00
abstract::Turbulent blood flow in medical devices contributes to blood trauma, yet the exact mechanism(s) have not been fully elucidated. Local turbulent stresses, viscous stresses, and the rate of dissipation of the turbulent kinetic energy have been proffered as hypotheses to describe and predict blood damage. In this work, s...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12572
更新日期:2015-12-01 00:00:00
abstract::Characteristics of morphology, cardiac function, and cardiac reserve at late state were evaluated at rest, by changing the pacing rates, and after exercise in patients with ventricular pacemakers for isolated congenital complete atrioventricular block. Heart size was reduced statistically after pacemaker implantation,...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1987.tb02667.x
更新日期:1987-06-01 00:00:00
abstract::The flow of blood as a viscous, Newtonian, incompressible liquid in an expanding spherical cavity with a ball-type inlet valve was examined. This type of flow can serve as a model of the phase of ventricular diastole in a sac-type artificial heart. The critical values of Reynolds numbers at which flow interruption beh...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1983.tb04170.x
更新日期:1983-02-01 00:00:00
abstract::This paper discussed issues of ethical assessment and moral concern associated with organ replacement and physical enhancement: research, allocation, organ donation, artificial organs, xenografts, biomaterials, and neuromaterials. While emphasizing the medical and moral benefits over associated risks, it calls for a b...
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
abstract::The new Advanced ventricular assist device (Advanced VAD) has many features such as improving pulsatility and preventing regurgitant flow during pump stoppage. The purpose of this study was to evaluate the effects of design modifications of the Advanced VAD on these features in vitro. Bench testing of four versions of...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13484
更新日期:2019-10-01 00:00:00
abstract::In patients undergoing exchange-transfusion with hemoglobin (Hb)-based oxygen (O₂) carriers (HBOC), native Hb coexists with newly transfused Hb. The two Hb types share the same arterial and venous PO₂, but their affinities for O₂ vary. A simple spreadsheet model is described aiming at evaluating the contribution of ea...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2011.01296.x
更新日期:2012-02-01 00:00:00
abstract::The durability of ventricular assist device (VAD) therapy improved steadily over the past years. However, driveline infections remain a challenge. To test whether an improved surgical implantation technique may lower the incidence of infections, we analyzed all patients receiving a VAD implantation in the years 2008 a...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12036
更新日期:2013-01-01 00:00:00
abstract::We were encouraged to investigate the reasons for large amounts of foam observed in bloodlines during hemodialysis (HD). Foam was visible in the venous air trap within the Artis Gambro dialysis device. Estimates of the extent of foam were graded (0-no foam, 10-extensive foam) by two persons that were blind to the type...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.13070
更新日期:2018-05-01 00:00:00
abstract::Although it is now understood that trained skeletal muscle can generate enough steady-state power to provide significant circulatory support, there are currently no means by which to tap this endogenous energy source to aid the failing heart. To that end, an implantable muscle energy converter (MEC) has been construct...
journal_title:Artificial organs
pub_type: 杂志文章,评审
doi:10.1111/j.1525-1594.2005.29108.x
更新日期:2005-09-01 00:00:00
abstract::In 1993, the development began of a small axial flow blood pump, the DeBakey ventricular assist device (VAD). The material was recently converted to a titanium alloy, and a waterproof pump package was incorporated for long-term intracorporeal circulation. Thirteen intrathoracic implantations in calves were achieved. N...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1046/j.1525-1594.1999.06300.x
更新日期:1999-12-01 00:00:00
abstract::Rheologic factors are likely to influence the balance between thrombotic and antithrombotic forces at the level of the vascular wall. In this study, the effects of flow-velocity/wall shear stress on the interaction of antithrombin (AT) with surface-immobilized heparin were investigated. The binding of AT to low-affini...
journal_title:Artificial organs
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract::Tissue engineering of cardiovascular structures represents a novel approach to improve clinical strategies in heart valve disease treatment. The aim of this study was to engineer decellularized atrioventricular heart valve neoscaffolds with an intact ultrastructure and to reseed them with umbilical cord-derived endoth...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12321
更新日期:2014-07-01 00:00:00
abstract::When cavitation occurs near a material surface of a mechanical heart valve (MHV), pits on the surface of the MHV and hemolysis are caused. Therefore, it is very important to investigate the possibility of the occurrence of cavitation in an MHV. To study the possibility of cavitation occurrence in a 25 mm Björk-Shiley ...
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
abstract::We recently experienced a case of a female hemodialysis patient with multiple intestinal angiodysplasias. In 2001, she complained of melena, and angiographic embolization halted bleeding from ileum angiodysplasia. In 2002, she again complained of black stool. Abdominal angiography found jejunum angiodysplasia, and pha...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2004.29003.x
更新日期:2005-01-01 00:00:00
abstract::Few instruments are currently available to test mitral valve function in an ex vivo state due to the technical difficulties involved. To investigate the native ex vivo mitral valve or prosthetic mitral valve with chordae, we developed a mitral valve adapter with an annulus suturing portion and 2 papillary muscle sutur...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.1999.06293.x
更新日期:1999-10-01 00:00:00
abstract::Thrombosis and thromboembolism are the life-threatening clinical complications for patients supported or treated with prosthetic cardiovascular devices. The high mechanical shear stress within these devices is believed to be the major contributing factor to cause platelet activation (PA) and function alteration, leadi...
journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12438
更新日期:2015-07-01 00:00:00