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Toda K, Bernhardt AM, Mehra MR. Mechanical circulatory support for adults in Japan: A 10-year perspective. Artif Organs 2023. [PMID: 37140177 DOI: 10.1111/aor.14536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 02/06/2023] [Accepted: 04/06/2023] [Indexed: 05/05/2023]
Abstract
Globalization in Asia and consequent strengthening of healthcare economic factors in tandem with an increasing heart failure (HF) population have enhanced potential for development and progress in the fields of HF medicine and mechanical circulatory support (MCS). In Japan, there are unique opportunities to investigate the outcome of acute and chronic MCS and a national registry for percutaneous and implantable left ventricular assist device (LVAD) including Impella pumps has been established. A Peripheral extracorporeal membrane oxygenation (ECMO) for acute MCS has been used in more than 7000 patients annually and Impella usage in more than 4000 patients over the past 4 years was noted. Recently, a novel centrifugal pump with hydrodynamically levitated impeller was developed and approved for mid-term extracorporeal circulatory support. In terms of chronic MCS more than 1200 continuous flow LVADs have been implanted during the past decade, and 2-year survival rate after primary LVAD implantation is 91%. Because of donor organ shortage, more than 70% of heart transplant recipients required LVAD support for more than 3 years and prevention and treatment of complications during long-term LVAD support have become important. Five important topics including hemocompatibility-related complications, LVAD infections, aortic valve insufficiency, right ventricular failure and cardiac recovery during LVAD support are discussed in this review for improving clinical outcomes. Findings from Japan will continue to provide useful information regarding MCS for the Asia-Pacific region and beyond.
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Affiliation(s)
- Koichi Toda
- Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Alexander M Bernhardt
- Department of Cardiovascular Surgery, University Heart and Vascular Center Hamburg, Hamburg, Germany
| | - Mandeep R Mehra
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Zhou M, Qi Z, Xia Z, Li Y, Ling W, Yang J, Yang Z, Pei J, Wu D, Huo W, Huang X. Miniaturized soft centrifugal pumps with magnetic levitation for fluid handling. SCIENCE ADVANCES 2021; 7:eabi7203. [PMID: 34705505 PMCID: PMC8550243 DOI: 10.1126/sciadv.abi7203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Centrifugal pumps are essential mechanical components for liquid delivery in many biomedical systems whose miniaturization can promote innovative disease treatment approaches. However, centrifugal pumps are predominately constructed by rigid and bulky components. Here, we combine the soft materials and flexible electronics to achieve soft magnetic levitation micropumps (SMLMs) that are only 1.9 to 12.8 grams in weight. The SMLMs that rotate at a rotation speed of 1000 revolutions per min to pump liquids with various viscosities ranging from 1 to 6 centipoise can be used in assisting dialysis, blood circulation, and skin temperature control because of excellent biocompatibility with no organ damage. The development of SMLMs not only demonstrates the possibility to replace rigid rotating structures with soft materials for handling large volumes of fluids but also indicates the potential for fully flexible artificial organs that may revolutionize health care and improve the well-being of patients.
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Affiliation(s)
- Mingxing Zhou
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Zhijie Qi
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Zhiqiang Xia
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Ya Li
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Wei Ling
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Jingxuan Yang
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Zhen Yang
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Ji Pei
- National Research Center of Pumps, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China
| | - Dazhuan Wu
- College of Energy Engineering, Zhejiang University, 38 Zheda Road, Hangzhou, Zhejiang 310027, China
| | - Wenxing Huo
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
- Corresponding author. (W.H.); (X.H.)
| | - Xian Huang
- Department of Biomedical Engineering, Tianjin University, 92 Weijin Road, Tianjin 300072, China
- Corresponding author. (W.H.); (X.H.)
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Assis A, Camargo S, Margalit R, Mitrani E. Creation of a vascular inducing device using mesenchymal stem cells to induce angiogenesis. J Biosci Bioeng 2021; 132:408-416. [PMID: 34326013 DOI: 10.1016/j.jbiosc.2021.06.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 06/14/2021] [Accepted: 06/29/2021] [Indexed: 12/13/2022]
Abstract
Conventional treatments of peripheral vascular disease and coronary artery disease have partial success but are still limited. Methods to deliver angiogenic factors into ischemic areas using gene, protein and cell therapies are faced with difficult issues such a delivery, effective concentration and duration of action. Tissue engineering offers the possibility of creating a functional self-contained three-dimensional (3D) unit that works as a coordinated biological pump that can secrete a whole range of angiogenic factors. We report a tissue engineering approach using decellularized micro-fragments and mesenchymal stem cells (MSCs) to create a vascular inducing device (VID). Proteomic analysis of the decellularized micro-fragments and of the VIDs reveals a large number of extracellular-matrix (ECM) proteins. Moreover, the VIDs were found to transcribe and secrete a whole repertoire of angiogenic factors in a sustained manner. Furthermore, preliminary results of implantation VIDs into non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice indicate formation of vascular network at the site within a week. We propose that those VIDs could serve as a safe, localized, simple and powerful method for the treatment of certain types of vascular diseases.
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Affiliation(s)
- Assaf Assis
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Givat Ram Campus, Jerusalem 91904, Israel
| | - Sandra Camargo
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Givat Ram Campus, Jerusalem 91904, Israel
| | | | - Eduardo Mitrani
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Givat Ram Campus, Jerusalem 91904, Israel.
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Köhne I. Kontinuierlich fördernde Blutpumpen für die Langzeitherzunterstützung. ZEITSCHRIFT FUR HERZ THORAX UND GEFASSCHIRURGIE 2020. [DOI: 10.1007/s00398-020-00398-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Effect of the Center Post Establishment and Its Design Variations on the Performance of a Centrifugal Rotary Blood Pump. Cardiovasc Eng Technol 2020; 11:337-349. [PMID: 32410073 DOI: 10.1007/s13239-020-00464-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 05/02/2020] [Indexed: 11/27/2022]
Abstract
PURPOSE The main purpose is to compare the characteristics and performance of a centrifugal blood pump with and without center post. Furthermore, to propose a center post design guide for the development of centrifugal blood pumps: finding the appropriate height and diameter of the center post. METHODS A centrifugal blood pump with different center post configurations is investigated using Computational Fluid Dynamics (CFD) in an extensive parametric approach. Height and diameter of the center post are varied on 4 levels each. Pressure head and hydraulic efficiency curves, pressure and velocity contours and volumetric histograms of scalar shear stress (SSS) distribution are discussed in detail. RESULTS The simulation results show uniform pressure distribution around the casing in the baseline design. Although obtaining the minimum Normalized Index of Hemolysis (NIH), average scalar shear stress (ASSS), and volumetric percentage ratios (SSS > 9, 50 and 150 Pa), a stagnation and recirculation zone in the impeller eye above the casing bottom is detected in center post free (H = 0 mm) pump. With the establishment and further increase of the center post height, the stagnation zone disappears gradually. The results also indicate that flow recirculation and stagnation around the circumference of the center post occurs when the center post has a small diameter. As the diameter increases, a reversed flow is formed between the impeller and the center post. CONCLUSIONS The center post can greatly reduce the stagnation zone occurring in the center post free pump. The diameter of center post makes a difference to the flow field in the gap between the impeller and the center post.
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Fang P, Du J, Yu S. Impeller (straight blade) design variations and their influence on the performance of a centrifugal blood pump. Int J Artif Organs 2020; 43:782-795. [PMID: 32312159 DOI: 10.1177/0391398820913559] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION The miniaturization of blood pumps has become a trend due to the advantage of easier transplantation, especially for pediatric patients. In small-scale pumps, it is much easier and more cost-efficient to manufacture the impeller with straight blades compared to spiral-profile blades. METHODS Straight-blade impeller designs with different blade angles, blade numbers, and impeller flow passage positions are evaluated using the computational fluid dynamics method. Blade angles (θ = 0°, 20°, 30°, and 40°), blade numbers (N = 5, 6, 7, and 8), and three positions of impeller flow passage (referred to as top, middle, and bottom) are selected as the studied parametric values. RESULTS The numerical results reveal that with increasing blade angle, the pressure head and the hydraulic efficiency increase, and the average scalar shear stress and the normalized index of hemolysis decrease. The minimum radial force and axial thrust are obtained when θ equals 20°. In addition, the minimum average scalar shear stress and normalized index of hemolysis values are obtained when N = 6, and the maximum values are obtained when N = 5. Regarding the impeller flow passage position, the axial thrust and the stagnation area forming in the impeller eye are reduced as the flow passage height declines. CONCLUSION The consideration of a blade angle can greatly improve the performance of blood pumps, although the influence of the blade number is not very easily determined. The bottom position of the impeller flow passage is the best design.
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Affiliation(s)
- Peng Fang
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, China
| | - Jianjun Du
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, China
| | - Shunzhou Yu
- Shenzhen Core Medical Technology Co., Ltd, Shenzhen, China
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Fukushima N, Tatsumi E, Seguchi O, Takewa Y, Hamasaki T, Onda K, Yamamoto H, Hayashi T, Fujita T, Kobayashi J. Assessment of Safety and Effectiveness of the Extracorporeal Continuous-Flow Ventricular Assist Device (BR16010) Use as a Bridge-to-Decision Therapy for Severe Heart Failure or Refractory Cardiogenic Shock: Study Protocol for Single-Arm Non-randomized, Uncontrolled, and Investigator-Initiated Clinical Trial. Cardiovasc Drugs Ther 2019; 32:373-379. [PMID: 29948739 PMCID: PMC6133189 DOI: 10.1007/s10557-018-6796-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The management of heart failure patients presenting in a moribund state remains challenging, despite significant advances in the field of ventricular assist systems. Bridge to decision involves using temporary devices to stabilize the hemodynamic state of such patients while further assessment is performed and a decision can be made regarding patient management. The purpose of this study (NCVC-BTD_01, National Cerebral and Cardiovascular Center-Bridge to Dicision_01) is to assess the safety and effectiveness of the newly developed extracorporeal continuous-flow ventricular assist system employing a disposable centrifugal pump with a hydrodynamically levitated bearing (BR16010) use as a bridge-to-decision therapy for patients with severe heart failure or refractory cardiogenic shock. METHOD/DESIGN NCVC-BTD_01 is a single-center, single-arm, open-label, exploratory, medical device, investigator-initiated clinical study. It is conducted at the National Cerebral and Cardiovascular Center in Japan. A total of nine patients will be enrolled in the study. The study was planned using Simon's minimax two-stage phase design. The primary endpoint is a composite of survival free of device-related serious adverse events and complications during device support. For left ventricular assistance, withdrawal of a trial device due to cardiac function recovery or exchange to other ventricular assist devices (VADs) for the purpose of bridge to transplantation (BTT) during 30 days after implantation will be considered study successes. For right ventricular assistance, withdrawal of tal device due to right ventricular function recovery within 30 days after implantation will be considered a study success. Secondary objectives include changes in brain natriuretic peptide levels (7 days after implantation of a trial device and the day of withdrawal of a trial device), period of mechanical ventricular support, changes in left ventricular ejection fraction (7 days after implantation of a trial device and the day of withdrawal of a trial device), and changes in left ventricular diastolic dimension (7 days after implantation of a trial device and the day of withdrawal of a trial device). ETHICS AND DISSEMINATION We will disseminate the findings through regional, national, and international conferences and through peer-reviewed journals. TRIAL REGISTRATION UMIN Clinical Trials Registry (UMIN-CTR; R000033243) registered on 8 September 2017.
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Affiliation(s)
- Norihide Fukushima
- Department of Transplant Medicine, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
| | - Eisuke Tatsumi
- Department of Artificial Organs, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Osamu Seguchi
- Department of Transplant Medicine, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Yoshiaki Takewa
- Department of Artificial Organs, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Toshimitsu Hamasaki
- Department of Data Science, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Kaori Onda
- Department of Data Science, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Haruko Yamamoto
- Center for Advancing Clinical and Translational Sciences, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Teruyuki Hayashi
- Deaprtment of Clinical Engineering, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Tomoyuki Fujita
- Department of Cardiac Surgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Junjiro Kobayashi
- Department of Cardiac Surgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
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Wu Y, Zhu LF, Luo Y. Development and current clinical application of ventricular assist devices in China. J Zhejiang Univ Sci B 2017; 18:934-945. [PMID: 29119731 DOI: 10.1631/jzus.b1600405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Heart failure has become one of the biggest threats to human health. Transplantation remains the most effective therapy for heart failure, but because of the shortage of donors, it cannot meet the demand. Ventricular assist devices (VADs) were developed to treat heart failure, and have now been clinically applied worldwide. As the country with the largest population, China is also facing the threat of heart failure. However, the development of VADs in China is very slow and is seldom discussed. This paper first talks about the background for VAD development in China. Then several home-developed VADs in China are introduced. The current clinical application status of VADs in China is also presented. Finally the challenge and opportunity for VAD development in China are discussed.
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Affiliation(s)
- Yue Wu
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liang-Fan Zhu
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yun Luo
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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Kishimoto S, Takewa Y, Tsukiya T, Mizuno T, Date K, Sumikura H, Fujii Y, Ohnuma K, Togo K, Katagiri N, Naito N, Kishimoto Y, Nakamura Y, Nishimura M, Tatsumi E. Novel temporary left ventricular assist system with hydrodynamically levitated bearing pump for bridge to decision: initial preclinical assessment in a goat model. J Artif Organs 2017; 21:23-30. [PMID: 28900738 DOI: 10.1007/s10047-017-0989-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 08/02/2017] [Indexed: 12/01/2022]
Abstract
The management of heart failure patients presenting in a moribund state remains challenging, despite significant advances in the field of ventricular assist systems. Bridge to decision involves using temporary devices to stabilize the hemodynamic state of such patients while further assessment is performed and a decision can be made regarding patient management. We developed a new temporary left ventricular assist system employing a disposable centrifugal pump with a hydrodynamically levitated bearing. We used three adult goats (body weight, 58-68 kg) to investigate the 30-day performance and hemocompatibility of the newly developed left ventricular assist system, which included the pump, inflow and outflow cannulas, the extracorporeal circuit, and connectors. Hemodynamic, hematologic, and blood chemistry measurements were investigated as well as end-organ effect on necropsy. All goats survived for 30 days in good general condition. The blood pump was operated at a rotational speed of 3000-4500 rpm and a mean pump flow of 3.2 ± 0.6 L min. Excess hemolysis, observed in one goat, was due to the inadequate increase in pump rotational speed in response to drainage insufficiency caused by continuous contact of the inflow cannula tip with the left ventricular septal wall in the early days after surgery. At necropsy, no thrombus was noted in the pump, and no damage caused by mechanical contact was found on the bearing. The newly developed temporary left ventricular assist system using a disposable centrifugal pump with hydrodynamic bearing demonstrated consistent and satisfactory hemodynamic performance and hemocompatibility in the goat model.
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Affiliation(s)
- Satoru Kishimoto
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan. .,Division of Organ Regeneration Surgery, Department of Surgery, Faculty of Medicine, Tottori University, Tottori, Japan.
| | - Yoshiaki Takewa
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Tomonori Tsukiya
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Toshihide Mizuno
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Kazuma Date
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Hirohito Sumikura
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Yutaka Fujii
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Kentaro Ohnuma
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Konomi Togo
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Nobumasa Katagiri
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Noritsugu Naito
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan
| | - Yuichiro Kishimoto
- Division of Organ Regeneration Surgery, Department of Surgery, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Yoshinobu Nakamura
- Division of Organ Regeneration Surgery, Department of Surgery, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Motonobu Nishimura
- Division of Organ Regeneration Surgery, Department of Surgery, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Eisuke Tatsumi
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
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In Vitro Thrombogenesis Resulting from Decreased Shear Rate and Blood Coagulability. Int J Artif Organs 2016; 39:194-9. [DOI: 10.5301/ijao.5000496] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2016] [Indexed: 11/20/2022]
Abstract
In vitro antithrombogenic testing with mock circulation is a useful type of pre-evaluation in ex vivo testing of mechanical assist devices. For effective in vitro testing, we have been developing a clear quantitative thrombogenesis model based on shear stress and blood coagulability. Bovine blood was used as the test medium. The activating clotting time (ACT) was adjusted with trisodium citrate and calcium chloride from 200 to 1,000 seconds. The blood was then applied to a rheometer and subjected to shear at 50 to 2,880 s-1. Blood coagulation time and degree of thrombogenesis were measured by the torque sensor of the rheometer. Prothrombin time (PT) and activated partial thromboplastin time (APTT) of the test blood were also measured after the application of shear. Blood coagulation time increased, and the degree of thrombogenesis decreased, with increases in shear rate to between 50 and 2,880 s-1. for test bloods with ACTs of 200 to 250 seconds. An ACT of 200 to 250 seconds is thus appropriate for in vitro antithrombogenic testing under a shear rate of 2,880 s-1. APTT was prolonged, whereas PT did not change, with increasing shear rate: that is, increasing the shear rate reduced thrombogenesis related to the intrinsic clotting pathway. An ACT of 200 to 250 seconds was suitable for in vitro antithrombogenic testing, and increasing the shear stress generated in the mechanical assist device reduced thrombogenesis via the intrinsic clotting pathway.
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