1
|
Huang X, Shen Y, Liu Y, Zhang H. Current status and future directions in pediatric ventricular assist device. Heart Fail Rev 2024; 29:769-784. [PMID: 38530587 DOI: 10.1007/s10741-024-10396-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/07/2024] [Indexed: 03/28/2024]
Abstract
A ventricular assist device (VAD) is a form of mechanical circulatory support that uses a mechanical pump to partially or fully take over the function of a failed heart. In recent decades, the VAD has become a crucial option in the treatment of end-stage heart failure in adult patients. However, due to the lack of suitable devices and more complicated patient profiles, this therapeutic approach is still not widely used for pediatric populations. This article reviews the clinically available devices, adverse events, and future directions of design and implementation in pediatric VADs.
Collapse
Affiliation(s)
- Xu Huang
- Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
- Department of Cardiothoracic Surgery, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
- Shanghai Clinical Research Center for Rare Pediatric Diseases, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
| | - Yi Shen
- Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
- Department of Cardiothoracic Surgery, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
- Shanghai Clinical Research Center for Rare Pediatric Diseases, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China
| | - Yiwei Liu
- Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
- Department of Cardiothoracic Surgery, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
- Shanghai Clinical Research Center for Rare Pediatric Diseases, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
| | - Hao Zhang
- Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
- Department of Cardiothoracic Surgery, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
- Shanghai Clinical Research Center for Rare Pediatric Diseases, Shanghai Children's Medical Center, National Children's Medical Center, Shanghai Jiaotong University School of Medicine, No. 1678, Dongfang Rd, Pudong District, Shanghai, 200127, China.
| |
Collapse
|
2
|
Wagner MS, Kranz M, Krenkel L, Pointner D, Foltan M, Lubnow M, Lehle K. Computer based visualization of clot structures in extracorporeal membrane oxygenation and histological clot investigations for understanding thrombosis in membrane lungs. Front Med (Lausanne) 2024; 11:1416319. [PMID: 38962744 PMCID: PMC11219572 DOI: 10.3389/fmed.2024.1416319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 06/06/2024] [Indexed: 07/05/2024] Open
Abstract
Extracorporeal membrane oxygenation (ECMO) was established as a treatment for severe cardiac or respiratory disease. Intra-device clot formation is a common risk. This is based on complex coagulation phenomena which are not yet sufficiently understood. The objective was the development and validation of a methodology to capture the key properties of clots deposed in membrane lungs (MLs), such as clot size, distribution, burden, and composition. One end-of-therapy PLS ML was examined. Clot detection was performed using multidetector computed tomography (MDCT), microcomputed tomography (μCT), and photography of fiber mats (fiber mat imaging, FMI). Histological staining was conducted for von Willebrand factor (vWF), platelets (CD42b, CD62P), fibrin, and nucleated cells (4', 6-diamidino-2-phenylindole, DAPI). The three imaging methods showed similar clot distribution inside the ML. Independent of the imaging method, clot loading was detected predominantly in the inlet chamber of the ML. The μCT had the highest accuracy. However, it was more expensive and time consuming than MDCT or FMI. The MDCT detected the clots with low scanning time. Due to its lower resolution, it only showed clotted areas but not the exact shape of clot structures. FMI represented the simplest variant, requiring little effort and resources. FMI allowed clot localization and calculation of clot volume. Histological evaluation indicated omnipresent immunological deposits throughout the ML. Visually clot-free areas were covered with leukocytes and platelets forming platelet-leukocyte aggregates (PLAs). Cells were embedded in vWF cobwebs, while vWF fibers were negligible. In conclusion, the presented methodology allowed adequate clot identification and histological classification of possible thrombosis markers such as PLAs.
Collapse
Affiliation(s)
- Maria S. Wagner
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Michael Kranz
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Lars Krenkel
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Daniel Pointner
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Maik Foltan
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Matthias Lubnow
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Karla Lehle
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| |
Collapse
|
3
|
Li Y, Xi Y, Wang H, Sun A, Wang L, Deng X, Chen Z, Fan Y. Development and validation of a mathematical model for evaluating shear-induced damage of von Willebrand factor. Comput Biol Med 2023; 164:107379. [PMID: 37597407 DOI: 10.1016/j.compbiomed.2023.107379] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/10/2023] [Accepted: 08/14/2023] [Indexed: 08/21/2023]
Abstract
PURPOSE To develop a mathematical model for predicting shear-induced von Willebrand factor (vWF) function modification which can be used to guide ventricular assist devices (VADs) design, and evaluate the damage of high molecular weight multimers (HMWM)-vWF in VAD patients for reducing clinical complications. METHODS Mathematical models were constructed based on three morphological variations (globular vWF, unfolded vWF and degraded vWF) of vWF under shear stress conditions, in which parameters were obtained from previous studies or fitted by experimental data. Different clinical support modes (pediatric vs. adult mode), different VAD operating states (pulsation vs. constant mode) and different clinical VADs (HeartMate II, HeartWare and CentriMag) were utilized to analyze shear-induced damage of HMWM-vWF based on our vWF model. The accuracy and feasibility of the models were evaluated using various experimental and clinical cases, and the biomechanical mechanisms of HMWM-vWF degradation induced by VADs were further explained. RESULTS The mathematical model developed in this study predicted VAD-induced HMWM-vWF degradation with high accuracy (correlation with experimental data r2 > 0.99). The numerical results showed that VAD in the pediatric mode resulted in more HMWM-vWF degradation per unit time and per unit flow rate than in the adult mode. However, the total degradation of HMWM-vWF is less in the pediatric mode than in the adult mode because the pediatric mode has fewer times of blood circulation than the adult mode in the same amount of time. The ratio of HMWM-vWF degradation was lower in the pulsation mode than in the constant mode. This is due to the increased flushing of VADs in the pulsation mode, which avoids prolonged stagnation of blood in high shear regions. This study also found that the design feature, rotor size and volume of the VADs, and the superimposed regions of high shear stress and long residence time inside VADs affect the degradation of HMWM-vWF. The axial flow VADs (HeartMate II) showed higher degradation of HMWM-vWF compared to centrifugal VADs (HeartWare and CentriMag). Compared to fully magnetically suspended VADs (CentriMag), hydrodynamic suspended VADs (HeartWare) produced extremely high degradation of HWMW-vWF in its narrow hydrodynamic clearance. Finally, the study used a mathematical model of HMWM-vWF degradation to interpret the clinical statistics from a biomechanical perspective and found that minimizing the rotating speed of VADs within reasonable limits helps to reduce HWMW-vWF degradation. All predicted conclusions are supported by the experimental and clinical data. CONCLUSION This study provides a validated mathematical model to assess the shear-induced degradation of HMWM-vWF, which can help to evaluate the damage of HMWM-vWF in patients implanted with VADs for reducing clinical complications, and to guide the optimization of VADs for improving hemocompatibility.
Collapse
Affiliation(s)
- Yuan Li
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Yifeng Xi
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Hongyu Wang
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Anqiang Sun
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Lizhen Wang
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Xiaoyan Deng
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Zengsheng Chen
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
| | - Yubo Fan
- Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
| |
Collapse
|
4
|
Sahni A, McIntyre EE, Cao K, Pal JD, Mukherjee D. The Relation Between Viscous Energy Dissipation and Pulsation for Aortic Hemodynamics Driven by a Left Ventricular Assist Device. Cardiovasc Eng Technol 2023; 14:560-576. [PMID: 37340092 DOI: 10.1007/s13239-023-00670-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 05/15/2023] [Indexed: 06/22/2023]
Abstract
Left ventricular assist device (LVAD) provides mechanical circulatory support for patients with advanced heart failure. Treatment using LVAD is commonly associated with complications such as stroke and gastro-intestinal bleeding. These complications are intimately related to the state of hemodynamics in the aorta, driven by a jet flow from the LVAD outflow graft that impinges into the aorta wall. Here we conduct a systematic analyses of hemodynamics driven by an LVAD with a specific focus on viscous energy transport and dissipation. We conduct a complementary set of analysis using idealized cylindrical tubes with diameter equivalent to common carotid artery and aorta, and a patient-specific model of 27 different LVAD configurations. Results from our analysis demonstrate how energy dissipation is governed by key parameters such as frequency and pulsation, wall elasticity, and LVAD outflow graft surgical anastomosis. We find that frequency, pulsation, and surgical angles have a dominant effect, while wall elasticity has a weaker effect, in determining the state of energy dissipation. For the patient-specific scenario, we also find that energy dissipation is higher in the aortic arch and lower in the abdominal aorta, when compared to the baseline flow without an LVAD. This further illustrates the key hemodynamic role played by the LVAD outflow jet impingement, and subsequent aortic hemodynamics during LVAD operation.
Collapse
Affiliation(s)
- Akshita Sahni
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, USA
| | - Erin E McIntyre
- Department of Surgery, University of Colorado, Anschutz Medical Campus, Aurora, USA
| | - Kelly Cao
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, USA
| | - Jay D Pal
- Department of Surgery, University of Washington, Seattle, USA
| | - Debanjan Mukherjee
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, USA.
| |
Collapse
|
5
|
Nguyen KT, Hecking J, Berg IC, Kannappan R, Donoghue L, Ismail E, Cheng X, Giridharan GA, Sethu P. von Willebrand Factor and Angiopoietin-2 are Sensitive Biomarkers of Pulsatility in Continuous-Flow Ventricular Assist Device Patients. ASAIO J 2023; 69:569-575. [PMID: 37000917 DOI: 10.1097/mat.0000000000001886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
Nonsurgical bleeding occurs in a significant proportion of patients implanted with continuous-flow ventricular assist devices (CF-VADs) and is associated with nonphysiologic flow with diminished pulsatility. An in vitro vascular pulse perfusion model seeded with adult human aortic endothelial cells (HAECs) was used to identify biomarkers sensitive to changes in pulsatility. Diminished pulsatility resulted in an ~45% decrease in von Willebrand factor (vWF) levels from 9.80 to 5.32 ng/ml (n = 5, p < 0.05) and a threefold increase in angiopoietin-2 (ANGPT-2) levels from 775.29 to 2471.93 pg/ml (n = 5, p < 0.05) in cultured HAECs. These changes are in agreement with evaluation of patient blood samples obtained pre-CF-VAD implant and 30-day postimplant: a decrease in plasma vWF level by 50% from ~45.59 to ~22.49 μg/ml (n = 15, p < 0.01) and a 64% increase in plasma ANGPT-2 level from 7,073 to 11,615 pg/ml (n = 8, p < 0.05). This study identified vWF and ANGPT-2 as highly sensitive to changes in pulsatility, in addition to interleukin-6 (IL-6), IL-8, and tumor necrosis-α (TNF-α). These biomarkers may help determine the optimal level of pulsatility and help identify patients at high risk of nonsurgical bleeding.
Collapse
Affiliation(s)
- Khanh T Nguyen
- From the Department of Biomedical Engineering, School of Engineering and School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Jana Hecking
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Ian C Berg
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Ramaswamy Kannappan
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Leslie Donoghue
- From the Department of Biomedical Engineering, School of Engineering and School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Esraa Ismail
- Department of Bioengineering and Department of Material Science, School of Engineering, Lehigh University, Bethlehem, Pennsylvania
| | - Xuanhong Cheng
- Department of Bioengineering and Department of Material Science, School of Engineering, Lehigh University, Bethlehem, Pennsylvania
| | - Guruprasad A Giridharan
- Department of Bioengineering, School of Engineering, University of Louisville, Louisville, Kentucky
| | - Palaniappan Sethu
- From the Department of Biomedical Engineering, School of Engineering and School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
- Division of Cardiovascular Disease, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
6
|
Jhun CS, Xu L, Siedlecki C, Bartoli CR, Yeager E, Lukic B, Scheib CM, Newswanger R, Cysyk JP, Shen C, Bohnenberger K, Weiss WJ, Rosenberg G. Kinetic and Dynamic Effects on Degradation of von Willebrand Factor. ASAIO J 2023; 69:467-474. [PMID: 36399789 PMCID: PMC10143388 DOI: 10.1097/mat.0000000000001848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The loss of high molecular weight multimers (HMWM) of von Willebrand factor (vWF) in aortic stenosis (AS) and continuous-flow left ventricular assist devices (cf-LVADs) is believed to be associated with high turbulent blood shear. The objective of this study is to understand the degradation mechanism of HMWM in terms of exposure time (kinetic) and flow regime (dynamics) within clinically relevant pathophysiologic conditions. A custom high-shear rotary device capable of creating fully controlled exposure times and flows was used. The system was set so that human platelet-poor plasma flowed through at 1.75 ml/sec, 0.76 ml/sec, or 0.38 ml/sec resulting in the exposure time ( texp ) of 22, 50, or 100 ms, respectively. The flow was characterized by the Reynolds number (Re). The device was run under laminar (Re = 1,500), transitional (Re = 3,000; Re = 3,500), and turbulent (Re = 4,500) conditions at a given texp followed by multimer analysis. No degradation was observed at laminar flow at all given texp . Degradation of HMWM at a given texp increases with the Re. Re ( p < 0.0001) and texp ( p = 0.0034) are significant factors in the degradation of HMWM. Interaction between Re and texp , however, is not always significant ( p = 0.73).
Collapse
Affiliation(s)
- Choon-Sik Jhun
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Lichong Xu
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Christopher Siedlecki
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
- Department of Biomedical Engineering, College of Engineering, The Pennsylvania State University, University Park, Pennsylvania
| | - Carlo R. Bartoli
- Department of Cardiothoracic Surgery, Geisinger Medical Center, Danville, Pennsylvania
| | - Eric Yeager
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Branka Lukic
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Christopher M. Scheib
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Raymond Newswanger
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Joshua P. Cysyk
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Chan Shen
- Division of Outcomes Research and Quality, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - Karl Bohnenberger
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
| | - William J. Weiss
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
- Department of Biomedical Engineering, College of Engineering, The Pennsylvania State University, University Park, Pennsylvania
| | - Gerson Rosenberg
- From the Division of Applied Biomedical Engineering, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania
- Department of Biomedical Engineering, College of Engineering, The Pennsylvania State University, University Park, Pennsylvania
| |
Collapse
|
7
|
Tan Z, Huo M, Qin K, El-Baz AS, Sethu P, Wang Y, Giridharan GA. A sensorless, physiologic feedback control strategy to increase vascular pulsatility for rotary blood pumps. Biomed Signal Process Control 2023; 83:104640. [PMID: 36936779 PMCID: PMC10019090 DOI: 10.1016/j.bspc.2023.104640] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Continuous flow rotary blood pumps (RBP) operating clinically at constant rotational speeds cannot match cardiac demand during varying physical activities, are susceptible to suction, diminish vascular pulsatility, and have an increased risk of adverse events. A sensorless, physiologic feedback control strategy for RBP was developed to mitigate these limitations. The proposed algorithm used intrinsic pump speed to obtain differential pump speed (ΔRPM). The proposed gain-scheduled proportional-integral controller, switching of setpoints between a higher pump speed differential setpoint (ΔRPM Hr ) and a lower pump speed differential setpoint (ΔRPM Lr ), generated pulsatility and physiologic perfusion, while avoiding suction. The switching between ΔRPM Hr and ΔRPM Lr setpoints occurred when the measured ΔRPM reached the pump differential reference setpoint. In-silico tests were implemented to assess the proposed algorithm during rest, exercise, a rapid 3-fold pulmonary vascular resistance increase, rapid change from exercise to rest, and compared with maintaining a constant pump speed setpoint. The proposed control algorithm augmented aortic pressure pulsatility to over 35 mmHg during rest and around 30 mmHg during exercise. Significantly, ventricular suction was avoided, and adequate cardiac output was maintained under all simulated conditions. The performance of the sensorless algorithm using estimation was similar to the performance of sensor-based method. This study demonstrated that augmentation of vascular pulsatility was feasible while avoiding ventricular suction and providing physiological pump outflows. Augmentation of vascular pulsatility can minimize adverse events that have been associated with diminished pulsatility. Mock circulation and animal studies would be conducted to validate these results.
Collapse
Affiliation(s)
- Zhehuan Tan
- School of Biomedical Engineering, Dalian University of Technology, Dalian, China
| | - Mingming Huo
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Kairong Qin
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Ayman S El-Baz
- Department of Bioengineering, University of Louisville, Louisville, KY, USA
| | - Palaniappan Sethu
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yu Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | | |
Collapse
|
8
|
Giridharan GA, Berg IC, Ismail E, Nguyen KT, Hecking J, Kirklin JK, Cheng X, Sethu P. Loss of pulsatility with continuous-flow left ventricular assist devices and the significance of the arterial endothelium in von-Willebrand factor production and degradation. Artif Organs 2023; 47:640-648. [PMID: 36404709 PMCID: PMC10065921 DOI: 10.1111/aor.14456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/06/2022] [Accepted: 11/04/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND Patients on continuous flow ventricular assist devices (CF-VADs) are at high risk for the development of Acquired von-Willebrand Syndrome (AVWS) and non-surgical bleeding. von Willebrand Factor (vWF) plays an essential role in maintaining hemostasis via platelet binding to the damaged endothelium to facilitate coagulation. In CF-VAD patients, degradation of vWF into low MW multimers that are inefficient in facilitating coagulation occurs and has been primarily attributed to the supraphysiological shear stress associated with the CF-VAD impeller. METHODS In this review, we evaluate information from the literature regarding the unraveling behavior of surface-immobilized vWF under pulsatile and continuous flow pertaining to: (A) the process of arterial endothelial vWF production and release into circulation, (B) the critical shear stress required to unravel surface bound versus soluble vWF which leads to degradation, and (C) the role of pulsatility in on the production and degradation of vWF. RESULTS AND CONCLUSION Taken together, these data suggests that the loss of pulsatility and its impact on arterial endothelial cells plays an important role in the production, release, unraveling, and proteolytic degradation of vWF into low MW multimers, contributing to the development of AVWS. Restoration of pulsatility can potentially mitigate this issue by preventing AVWS and minimizing the risk of non-surgical bleeding.
Collapse
Affiliation(s)
- Guruprasad A. Giridharan
- Department of Bioengineering, J. B. Speed School of Engineering, University of Louisville, Louisville, KY 40292
| | - Ian C. Berg
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, School of Engineering and Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
| | - Esraa Ismail
- Department of Bioengineering, Lehigh University, Bethlehem, PA, 18018
| | - Khanh T. Nguyen
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, School of Engineering and Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
| | - Jana Hecking
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, School of Engineering and Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
| | - James K. Kirklin
- Division of Cardiothoracic Surgery, Department of Surgery, Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
| | - Xuanhong Cheng
- Department of Materials Science and Engineering, Lehigh University, Bethlehem, PA, 18018
- Department of Bioengineering, Lehigh University, Bethlehem, PA, 18018
| | - Palaniappan Sethu
- Division of Cardiovascular Disease, Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, School of Engineering and Heersink School of Medicine, University of Alabama at Birmingham, AL 35294
| |
Collapse
|
9
|
Khalil F, Asleh R, Perue RK, Weinstein JM, Solomon A, Betesh-Abay B, Briasoulis A, Alnsasra H. Vascular Function in Continuous Flow LVADs: Implications for Clinical Practice. Biomedicines 2023; 11:biomedicines11030757. [PMID: 36979735 PMCID: PMC10045906 DOI: 10.3390/biomedicines11030757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/18/2023] [Accepted: 02/22/2023] [Indexed: 03/06/2023] Open
Abstract
Left ventricular assist devices (LVADs) have been increasingly used in patients with advanced heart failure, either as a destination therapy or as a bridge to heart transplant. Continuous flow (CF) LVADs have revolutionized advanced heart failure treatment. However, significant vascular pathology and complications have been linked to their use. While the newer CF-LVAD generations have led to a reduction in some vascular complications such as stroke, no major improvement was noticed in the rate of other vascular complications such as gastrointestinal bleeding. This review attempts to provide a comprehensive summary of the effects of CF-LVAD on vasculature, including pathophysiology, clinical implications, and future directions.
Collapse
Affiliation(s)
- Fouad Khalil
- Department of Internal Medicine, University of South Dakota, Sioux Falls, SD 57105, USA
| | - Rabea Asleh
- Heart Institute, Hadassah University Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem P.O. Box 12000, Israel
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55902, USA
| | - Radha Kanneganti Perue
- Department of Cardiovascular Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Jean-Marc Weinstein
- Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva P.O. Box 653, Israel
- Department of Cardiology, Soroka University Medical Center, Rager Av., Beersheva P.O. Box 84101, Israel
| | - Adam Solomon
- Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva P.O. Box 653, Israel
| | - Batya Betesh-Abay
- Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva P.O. Box 653, Israel
| | - Alexandros Briasoulis
- Department of Cardiovascular Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
| | - Hilmi Alnsasra
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55902, USA
- Faculty of Health Sciences, Ben Gurion University of the Negev, Beersheva P.O. Box 653, Israel
- Department of Cardiology, Soroka University Medical Center, Rager Av., Beersheva P.O. Box 84101, Israel
- Correspondence: ; Tel.: +972-507107535
| |
Collapse
|
10
|
Del Rio-Pertuz G, Nair N. Gastrointestinal bleeding in patients with continuous-flow left ventricular assist devices: A comprehensive review. Artif Organs 2023; 47:12-23. [PMID: 36334280 DOI: 10.1111/aor.14432] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/05/2022] [Accepted: 10/04/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Gastrointestinal bleeding is a major cause of morbidity that plagues the quality of life of patients supported on contemporary continuous-flow left ventricular assist devices (CF-LVADs). Despite benefits in survival and the nearly 50% reduction in complications provided by CF-LVADs, bleeding remains one of the most frequent adverse events with CF-LVAD implants. The CF-LVADs cause an increased risk of bleeding mainly due to the activation of the coagulation cascade. METHODS A literature search was done using PubMed and Google Scholar from Inception to February 2022. Qualitative analyses of the articles retrieved were used to construct this review. This review attempts to provide a comprehensive summary of the epidemiology, pathophysiology, risk stratification, and management of gastrointestinal bleeding as a complication of CF-LVAD as well as propose an algorithm for diagnosis and treatment. RESULTS Bleeding can occur at different sites in the gastrointestinal tract, the most common underlying pathology being arteriovenous malformations located in the upper gastrointestinal tract The increased prevalence of gastrointestinal (GI) bleeding in CF-LVAD patients has been attributed to the physiology of the LVAD itself, the use of anticoagulants, as well as patient comorbidities. Management involves pharmacologic and nonpharmacologic strategies. CONCLUSIONS CF-LVAD-supported patients have a significant risk of GI bleeding that is mainly caused by arteriovenous malformations located in the upper GI tract. The increased prevalence of GI bleeding in CF-LVAD patients is attributed to several etiologies that include factors attributed to the device itself and extrinsic factors such as the use of anticoagulation.
Collapse
Affiliation(s)
- Gaspar Del Rio-Pertuz
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Nandini Nair
- Division of Cardiology, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| |
Collapse
|