1
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Wang X, Liang L, Giridharan GA, Sethu P, Wang Y, Qin KR, Qu P, Wang Y. Development of in vitro microfluidic models to study endothelial responses to pulsatility with different mechanical circulatory support devices. Analyst 2024; 149:3661-3672. [PMID: 38819086 DOI: 10.1039/d4an00507d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Continuous-flow ventricular assist devices (CFVAD) and counterpulsation devices (CPD) are used to treat heart failure (HF). CFVAD can diminish pulsatility, but pulsatile modes have been implemented to increase vascular pulsatility. The effects of CFVAD in a pulsatile mode and CPD support on the function of endothelial cells (ECs) are yet to be investigated. In this study, two in vitro microfluidic models for culturing ECs are proposed to reproduce blood pressure (BP) and wall shear stress (WSS) on the arterial endothelium while using these medical devices. The layout and parameters of the two microfluidic systems were optimized based on the principle of hemodynamic similarity to efficiently simulate physiological conditions. Moreover, the unique design of the double-pump and double afterload systems could successfully reproduce the working mode of CPDs in an in vitro microfluidic system. The performance of the two systems was verified by numerical simulations and in vitro experiments. BP and WSS under HF, CFVAD in pulsatile modes, and CPD were reproduced accurately in the systems, and these induced signals improved the expression of Ca2+, NO, and reactive oxygen species in ECs, proving that CPD may be effective in normalizing endothelial function and replacing CFVAD to a certain extent to treat non-severe HF. This method offers an important tool for the study of cell mechanobiology and a key experimental basis for exploring the potential value of mechanical circulatory support devices in reducing adverse events and improving outcomes in the treatment of HF in the future.
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Affiliation(s)
- Xueying Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
| | - Lixue Liang
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
| | | | - Palaniappan Sethu
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yanxia Wang
- School of Rehabilitation Medicine, Shandong Second Medical University, Weifang 261053, Shandong Province, P. R. China
| | - Kai-Rong Qin
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China.
| | - Peng Qu
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China.
| | - Yu Wang
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China.
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2
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Liang L, Wang X, Chen D, Sethu P, Giridharan GA, Wang Y, Wang Y, Qin KR. Study on the hemodynamic effects of different pulsatile working modes of a rotary blood pump using a microfluidic platform that realizes in vitro cell culture effectively. LAB ON A CHIP 2024; 24:2428-2439. [PMID: 38625094 DOI: 10.1039/d4lc00159a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Rotary blood pumps (RBPs) operating at a constant speed generate non-physiologic blood pressure and flow rate, which can cause endothelial dysfunction, leading to adverse clinical events in peripheral blood vessels and other organs. Notably, pulsatile working modes of the RBP can increase vascular pulsatility to improve arterial endothelial function. However, the laws and related mechanisms of differentially regulating arterial endothelial function under different pulsatile working modes are still unclear. This knowledge gap hinders the optimal selection of the RBP working modes. To address these issues, this study developed a multi-element in vitro endothelial cell culture system (ECCS), which could realize in vitro cell culture effectively and accurately reproduce blood pressure, shear stress, and circumferential strain in the arterial endothelial microenvironment. Performance of this proposed ECCS was validated with numerical simulation and flow experiments. Subsequently, this study investigated the effects of four different pulsation frequency modes that change once every 1-4-fold cardiac cycles (80, 40, 80/3, and 20 cycles per min, respectively) of the RBP on the expression of nitric oxide (NO) and reactive oxygen species (ROS) in endothelial cells. Results indicated that the 2-fold and 3-fold cardiac cycles significantly increased the production of NO and prevented the excessive generation of ROS, potentially minimizing the occurrence of endothelial dysfunction and related adverse events during the RBP support, and were consistent with animal study findings. In general, this study may provide a scientific basis for the optimal selection of the RBP working modes and potential treatment options for heart failure.
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Affiliation(s)
- Lixue Liang
- Institute of Cardio-Cerebrovascular Medicine, Central Hospital of Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
- School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
| | - Xueying Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
| | - Dong Chen
- Institute of Cardio-Cerebrovascular Medicine, Central Hospital of Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
| | - Palaniappan Sethu
- Division of Cardiovascular Disease, Department of Medicine, School of Medicine and Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Yanxia Wang
- School of Rehabilitation Medicine, Shandong Second Medical University, Weifang 261053, Shandong Province, P. R. China
| | - Yu Wang
- Institute of Cardio-Cerebrovascular Medicine, Central Hospital of Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China.
| | - Kai-Rong Qin
- Institute of Cardio-Cerebrovascular Medicine, Central Hospital of Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China.
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3
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Huo M, Giridharan GA, Sethu P, Qu P, Qin K, Wang Y. Numerical simulation analysis of multi-scale computational fluid dynamics on hemodynamic parameters modulated by pulsatile working modes for the centrifugal and axial left ventricular assist devices. Comput Biol Med 2024; 169:107788. [PMID: 38091724 DOI: 10.1016/j.compbiomed.2023.107788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 11/08/2023] [Accepted: 11/28/2023] [Indexed: 02/08/2024]
Abstract
Continuous flow (CF) left ventricular assist devices (LVAD) operate at a constant speed mode, which could result in increased risk of adverse events due to reduced vascular pulsatility. Consequently, pump speed modulation algorithms have been proposed to augment vascular pulsatility. However, the quantitative local hemodynamic effects on the aorta when the pump is operating with speed modulation using different types of CF-LVADs are still under investigation. The computational fluid dynamics (CFD) study was conducted to quantitatively elucidate the hemodynamic effects on a clinical patient-specific aortic model under different speed patterns of CF-LVADs. Pressure distribution, wall shear stress (WSS), time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and velocity were calculated to compare their differences at constant and pulsatile speeds under centrifugal and axial LVAD support. Results showed that pulse pressure on the aorta was significantly larger under pulsatile speed mode than that under constant speed mode for both CF-LVADs, indicating enhanced aorta pulsatility, as well as the higher peak blood flow velocity on some representative slices of aorta. Pulsatile speed modulation enhanced peak WSS compared to constant speed; high TAWSS region appeared near the branch of left common carotid artery and distal aorta regardless of speed modes and CF-LVADs but these regions also had low OSI; RRT was almost the same for all the cases. This study may provide a basis for the scientific and reasonable selection of the pulsatile speed patterns of CF-LVADs for treating heart failure patients.
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Affiliation(s)
- Mingming Huo
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | | | - Palaniappan Sethu
- Division of Cardiovascular Disease, Department of Medicine, School of Medicine and Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Peng Qu
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian, China
| | - Kairong Qin
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian, China
| | - Yu Wang
- School of Biomedical Engineering, Faculty of Medicine, Dalian University of Technology, Dalian, China.
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4
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Yun Z, Yao J, Wang L, Tang X, Feng Y. The design and evaluation of the outflow structures of an interventional microaxial blood pump. Front Physiol 2023; 14:1169905. [PMID: 37250127 PMCID: PMC10213901 DOI: 10.3389/fphys.2023.1169905] [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: 02/20/2023] [Accepted: 05/04/2023] [Indexed: 05/31/2023] Open
Abstract
Blood pump design efforts are focused on enhancing hydraulic effectiveness and minimizing shear stress. Unlike conventional blood pumps, interventional microaxial blood pumps have a unique outflow structure due to minimally invasive technology. The outflow structure, composed of the diffuser and cage bridges, is crucial in minimizing the pump size to provide adequate hemodynamic support. This study proposed four outflow structures of an interventional microaxial blood pump depending on whether the diffuser with or without blades and cage bridges were straight or curved. The outflow flow structure's effect on the blood pump's hydraulic performance and shear stress distribution was evaluated by computational fluid dynamics and hydraulic experiments. The results showed that all four outflow structures could achieve the pressure and flow requirements specified at the design point but with significant differences in shear stress distribution. Among them, the outflow structure with curved bridges would make the blood dispersed more evenly when flowing out of the pump, which could effectively reduce the shear stress at the cage bridges. The outflow structure with blades would aggravate the secondary flow at the leading edge of the impeller, increasing the risk of flow stagnation. The combination of curved bridges and the bladeless diffuser had a relatively better shear stress distribution, with the proportion of fluid exposed to low scalar shear stress (<50 Pa) and high scalar shear stress (>150 Pa) in the blood pump being 97.92% and 0.26%, respectively. It could be concluded that the outflow structure with curved bridges and bladeless diffuser exhibited relatively better shear stress distribution and a lower hemolysis index of 0.00648%, which could support continued research on optimizing the microaxial blood pumps.
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Affiliation(s)
- Zhong Yun
- *Correspondence: Zhong Yun, ; Jinfu Yao,
| | - Jinfu Yao
- *Correspondence: Zhong Yun, ; Jinfu Yao,
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5
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Adji A, Shehab S, Jain P, Robson D, Jansz P, Hayward CS. Arterial Compliance and Continuous-Flow Left Ventricular Assist Device Pump Function. ASAIO J 2022; 68:925-931. [PMID: 35544445 DOI: 10.1097/mat.0000000000001768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Durable continuous-flow left ventricular assist devices (cfLVADs) demonstrate superior survival, cardiac functional status, and overall quality of life compared to medical therapy alone in advanced heart failure. Previous studies have not considered the impact arterial compliance may have on pump performance or developed arterial pressure. This study assessed the impact of alterations in arterial compliance, preload, and afterload on continuous-flow pump function and measured hemodynamics using an in-vitro pulsatile mock circulatory loop. Decreased arterial compliance was associated with a significant increase in arterial pressure pulsatility which was not evident in the flow pulsatility, as displayed in pump flow waveforms. There were marked changes in the pump flow waveforms due to the significant alteration in the aortoventricular gradient during diastole according to the changes in compliance. This study demonstrates that changes in systemic blood pressure, afterload, and left ventricular contractility each significantly affects the flow waveform. The association of hypertension with lower aortic compliance results in markedly decreased diastolic flow rates which may be important in contributing to a greater risk of adverse events under cfLVAD support.
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Affiliation(s)
- Audrey Adji
- From the Heart Failure and Transplant Unit, Cardiology Department, St Vincent's Hospital, Sydney, Australia
- Mechanical Circulatory Support Laboratory, Victor Chang Cardiac Research Institute, Sydney, Australia
- St Vincent's Clinical School, UNSW Medicine and Health, Sydney, Australia
- Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, Australia
| | - Sajad Shehab
- Mechanical Circulatory Support Laboratory, Victor Chang Cardiac Research Institute, Sydney, Australia
| | - Pankaj Jain
- From the Heart Failure and Transplant Unit, Cardiology Department, St Vincent's Hospital, Sydney, Australia
| | - Desiree Robson
- From the Heart Failure and Transplant Unit, Cardiology Department, St Vincent's Hospital, Sydney, Australia
| | - Paul Jansz
- From the Heart Failure and Transplant Unit, Cardiology Department, St Vincent's Hospital, Sydney, Australia
- Mechanical Circulatory Support Laboratory, Victor Chang Cardiac Research Institute, Sydney, Australia
- St Vincent's Clinical School, UNSW Medicine and Health, Sydney, Australia
- School of Medicine, University of Notre Dame, Sydney, Australia
| | - Christopher S Hayward
- From the Heart Failure and Transplant Unit, Cardiology Department, St Vincent's Hospital, Sydney, Australia
- Mechanical Circulatory Support Laboratory, Victor Chang Cardiac Research Institute, Sydney, Australia
- St Vincent's Clinical School, UNSW Medicine and Health, Sydney, Australia
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6
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Wang Y, Wang J, Peng J, Huo M, Yang Z, Giridharan GA, Luan Y, Qin K. Effects of a Short-Term Left Ventricular Assist Device on Hemodynamics in a Heart Failure Patient-Specific Aorta Model: A CFD Study. Front Physiol 2021; 12:733464. [PMID: 34621186 PMCID: PMC8491745 DOI: 10.3389/fphys.2021.733464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/20/2021] [Indexed: 11/24/2022] Open
Abstract
Patients with heart failure (HF) or undergoing cardiogenic shock and percutaneous coronary intervention require short-term cardiac support. Short-term cardiac support using a left ventricular assist device (LVAD) alters the pressure and flows of the vasculature by enhancing perfusion and improving the hemodynamic performance for the HF patients. However, due to the position of the inflow and outflow of the LVAD, the local hemodynamics within the aorta is altered with the LVAD support. Specifically, blood velocity, wall shear stress, and pressure difference are altered within the aorta. In this study, computational fluid dynamics (CFD) was used to elucidate the effects of a short-term LVAD for hemodynamic performance in a patient-specific aorta model. The three-dimensional (3D) geometric models of a patient-specific aorta and a short-term LVAD, Impella CP, were created. Velocity, wall shear stress, and pressure difference in the patient-specific aorta model with the Impella CP assistance were calculated and compared with the baseline values of the aorta without Impella CP support. Impella CP support augmented cardiac output, blood velocity, wall shear stress, and pressure difference in the aorta. The proposed CFD study could analyze the quantitative changes in the important hemodynamic parameters while considering the effects of Impella CP, and provide a scientific basis for further predicting and assessing the effects of these hemodynamic signals on the aorta.
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Affiliation(s)
- Yu Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Junwei Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Jing Peng
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Mingming Huo
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
| | - Zhiqiang Yang
- Department of Cardiovascular Computed Tomography (CT) Examination, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | | | - Yong Luan
- Department of Anesthesiology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Kairong Qin
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, China
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7
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Hydren JR, Gifford JR, Jarrett CL, Park SH, Shields KL, Broxterman RM, Kithas AC, Bisconti AV, Thurston TS, Ratchford SM, Wray DW, Stehlik J, Selzman CH, Drakos SG, Richardson RS. Vascular function in continuous-flow left ventricular assist device recipients: effect of a single pulsatility treatment session. Am J Physiol Regul Integr Comp Physiol 2021; 320:R425-R437. [PMID: 33438517 DOI: 10.1152/ajpregu.00274.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular function is further attenuated in patients with chronic heart failure implanted with a continuous-flow left ventricular assist device (LVAD), likely due to decreased arterial pulsatility, and this may contribute to LVAD-associated cardiovascular complications. However, the impact of increasing pulsatility on vascular function in this population is unknown. Therefore, 15 LVAD recipients and 15 well-matched controls underwent a 45-min, unilateral, arm pulsatility treatment, evoked by intermittent cuff inflation/deflation (2-s duty cycle), distal to the elbow. Vascular function was assessed by percent brachial artery flow-mediated dilation (%FMD) and reactive hyperemia (RH) (Doppler ultrasound). Pretreatment, %FMD (LVAD: 4.0 ± 1.7; controls: 4.2 ± 1.4%) and RH (LVAD: 340 ± 101; controls: 308 ± 94 mL) were not different between LVAD recipients and controls; however, %FMD/shear rate was attenuated (LVAD: 0.10 ± 0.04; controls: 0.17 ± 0.06%/s-1, P < 0.05). The LVAD recipients exhibited a significantly attenuated pulsatility index (PI) compared with controls prior to treatment (LVAD: 2 ± 2; controls: 15 ± 7 AU, P < 0.05); however, during the treatment, PI was no longer different (LVAD: 37 ± 38; controls: 36 ± 14 AU). Although time to peak dilation and RH were not altered by the pulsatility treatment, %FMD (LVAD: 7.0 ± 1.8; controls: 7.4 ± 2.6%) and %FMD/shear rate (LVAD: 0.19 ± 0.07; controls: 0.33 ± 0.15%/s-1) increased significantly in both groups, with, importantly, %FMD/shear rate in the LVAD recipients being restored to that of the controls pretreatment. This study documents that a localized pulsatility treatment in LVAD recipients and controls can recover local vascular function, an important precursor to the development of approaches to increase systemic pulsatility and reduce systemic vascular complications in LVAD recipients.
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Affiliation(s)
- Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Catherine L Jarrett
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Angela Valentina Bisconti
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Stephen M Ratchford
- Department of Health and Exercise Science, Appalachian State University, Boone, North Carolina
| | - D Walter Wray
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Josef Stehlik
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Craig H Selzman
- Department of Surgery, University of Utah School of Medicine, Salt Lake City, Utah
| | - Stavros G Drakos
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
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8
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Targeting Peripheral Vascular Pulsatility in Heart Failure Patients with Continuous-Flow Left Ventricular Assist Devices: The Impact of Pump Speed. ASAIO J 2020; 66:291-299. [PMID: 30973399 DOI: 10.1097/mat.0000000000001001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Current continuous-flow left ventricular assist devices (LVADs) decrease peripheral vascular pulsatility, which may contribute to side effects such as bleeding and thrombotic events. However, the actual impact of manipulating LVAD pump speed, revolutions per minute (rpm), on peripheral (brachial) pulsatility index (brachial PI), in patients with heart failure implanted with a HeartWare (HVAD) or HeartMateII (HMII) LVAD is unknown. Therefore, blood velocities (Doppler ultrasound) in the brachial artery were recorded and brachial PI calculated across rpm manipulations which spanned the acceptable clinical outpatient range: 360 rpm (HVAD, n = 10) and 1200 rpm (HMII, n = 10). Left ventricular assist device-derived PIs were also recorded: HVAD maximal blood flow (HVADV max), HVAD minimum blood flow (HVADV min), and HMII PI (HMIIPI). Brachial PI changed significantly with rpm manipulations, from 2.3 ± 0.6 to 4.1 ± 0.8 (HVAD) and from 1.8 ± 0.5 to 3.6 ± 1.0 (HMII). Multilevel linear modeling with random intercepts revealed a 180 rpm decrease of the HVAD resulted in a 0.9 ± 0.1 (37 ± 4%, d = 2.65) increase in brachial PI and a 600 rpm decrease in the HMII resulted in a 0.8 ± 0.1 (38 ± 3%, d = 4.66) increase. Furthermore, a reduction in rpm resulted in a 20.0 ± 0.3% power savings, and a reduction in device reported blood flow of 9 ± 1%. Brachial PI was linearly related to HVADV max, HVADV min, their difference (R = 0.42, R = 0.65, and R = 0.54, respectively), and HMIIPI (R = 0.86). Manipulating LVAD pump speed, within a clinically acceptable outpatient range, resulted in a significant change in brachial PI, which was reflected by pump indices, documenting the potential for LVAD pump speed manipulations to improve LVAD outcomes.
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9
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Symalla T, Jeevanandam V. Choosing the appropriate left ventricular assist device for your patient. Indian J Thorac Cardiovasc Surg 2020; 36:256-264. [PMID: 33061210 DOI: 10.1007/s12055-019-00890-3] [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: 09/26/2019] [Accepted: 10/10/2019] [Indexed: 10/25/2022] Open
Abstract
The increasing incidence of advanced heart failure and severe donor organ shortage for cardiac transplant has led to the development of implantable left ventricular assist devices (LVAD) for long-term mechanical circulatory support. There has been tremendous improvement in the device technology of LVADs, and there are a number of devices in use throughout the world. This article reviews the evidence behind each device and their unique features that can help when choosing a durable LVAD for an individual patient.
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Affiliation(s)
- Trever Symalla
- Department of Surgery Section of Cardiac Surgery, University of Chicago Medicine and Biological Sciences, Chicago, IL 60637 USA
| | - Valluvan Jeevanandam
- Department of Surgery Section of Cardiac Surgery, University of Chicago Medicine and Biological Sciences, Chicago, IL 60637 USA
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10
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What Really Matters? Understanding Quality of Life Determinants Impacting Ventricular Assist Device Stakeholders. ASAIO J 2020; 66:626-636. [DOI: 10.1097/mat.0000000000001175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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11
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Magkoutas K, Rebholz M, Sündermann S, Alogna A, Faragli A, Falk V, Meboldt M, Schmid Daners M. Control of ventricular unloading using an electrocardiogram-synchronized pulsatile ventricular assist device under high stroke ratios. Artif Organs 2020; 44:E394-E405. [PMID: 32321193 DOI: 10.1111/aor.13711] [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] [Received: 11/19/2019] [Revised: 03/10/2020] [Accepted: 04/13/2020] [Indexed: 01/17/2023]
Abstract
Pulsatile ventricular assist devices (pVADs) yield a blood flow that imitates the pulsatile flow of the heart and, therefore, could diminish the adverse events related to the continuous flow provided by the ventricular assist devices that are commonly used. However, their intrinsic characteristics of larger size and higher weight set a burden to their implantation, that along with the frequent mechanical failures and thrombosis events, reduce the usage of pVADs in the clinical environment. In this study, we investigated the possibility to reduce the pump size by using high pump stroke ratios while maintaining the ability to control the hemodynamics of the cardiovascular system (CVS). In vitro and in vivo experiments were conducted with a custom pVAD implemented on a hybrid mock circulation system and in five sheep, respectively. The actuation of the pVAD was synchronized with the heartbeat. Variations of the pump stroke ratio, time delay between the pump stroke and the heart stroke, as well as duration of the pump systole in respect to the total cardiac cycle duration were used to evaluate the effects of various pump settings on the hemodynamics of the CVS. The results suggest that by varying the operating settings of the pVAD, a pulsatile flow that provides physiological hemodynamic parameters, as well as a control over the hemodynamic parameters, can be achieved. Additionally, by employing high pump stroke ratios, the size of the pVAD can be significantly reduced; however, at those high pump stroke ratios, the effect of the other pump parameters diminishes.
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Affiliation(s)
- Konstantinos Magkoutas
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Mathias Rebholz
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Simon Sündermann
- DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Department of Cardiovascular Surgery, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany
| | - Alessio Alogna
- DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Virchow Klinikum, Berlin, Germany
| | - Alessandro Faragli
- DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Campus Virchow Klinikum, Berlin, Germany
| | - Volkmar Falk
- DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Department of Cardiovascular Surgery, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany.,Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Mirko Meboldt
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Marianne Schmid Daners
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
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12
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Wu T, Khir AW, Kütting M, Du X, Lin H, Zhu Y, Hsu PL. A review of implantable pulsatile blood pumps: Engineering perspectives. Int J Artif Organs 2020; 43:559-569. [PMID: 32037940 DOI: 10.1177/0391398820902470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
It has been reported that long-term use of continuous-flow mechanical circulatory support devices (CF-MCSDs) may induce complications associated with diminished pulsatility. Pulsatile-flow mechanical circulatory support devices (PF-MCSDs) have the potential of overcoming these shortcomings with the advance of technology. In order to promote in-depth understanding of PF-MCSD technology and thus encourage future mechanical circulatory support device innovations, engineering perspectives of PF-MCSD systems, including mechanical designs, drive mechanisms, working principles, and implantation strategies, are reviewed in this article. Some emerging designs of PF-MCSDs are introduced, and possible elements for next-generation PF-MCSDs are identified.
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Affiliation(s)
- Tingting Wu
- Artificial Organ Technology Laboratory, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Ashraf W Khir
- Brunel Institute for Bioengineering, Brunel University London, Uxbridge, UK
| | | | - Xinli Du
- Brunel Institute for Bioengineering, Brunel University London, Uxbridge, UK
| | - Hao Lin
- Artificial Organ Technology Laboratory, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Yuxin Zhu
- Artificial Organ Technology Laboratory, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Po-Lin Hsu
- Artificial Organ Technology Laboratory, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
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13
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White-Williams C, Fazeli PL, Kirklin JK, Pamboukian SV, Grady KL. Differences in health-related quality of life by implant strategy: Analyses from the Interagency Registry for Mechanically Assisted Circulatory Support. J Heart Lung Transplant 2020; 39:62-73. [DOI: 10.1016/j.healun.2019.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/28/2019] [Accepted: 10/28/2019] [Indexed: 11/24/2022] Open
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Merkler AE, Chen ML, Parikh NS, Murthy SB, Yaghi S, Goyal P, Okin PM, Karas MG, Navi BB, Iadecola C, Kamel H. Association Between Heart Transplantation and Subsequent Risk of Stroke Among Patients With Heart Failure. Stroke 2019; 50:583-587. [PMID: 30744541 DOI: 10.1161/strokeaha.118.023622] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose- It is uncertain whether heart transplantation decreases the risk of stroke. The objective of our study was to determine whether heart transplantation is associated with a decreased risk of subsequent stroke among patients with heart failure awaiting transplantation. Methods- We performed a retrospective cohort study using administrative data from New York, California, and Florida between 2005 and 2015. Individuals with heart failure awaiting heart transplantation were identified using previously validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes for heart failure in combination with code V49.83 for awaiting organ transplant status. Individuals with prior stroke were excluded. Our primary exposure variable was heart transplantation, modeled as a time-varying covariate and defined by procedure code 37.51. The primary outcome was stroke, defined as the composite of ischemic and hemorrhagic stroke. Survival statistics were used to calculate stroke incidence, and Cox proportional hazards analysis was used to determine the association between heart transplantation and stroke while adjusting for demographics, stroke risk factors, Elixhauser comorbidities, and implantation of a left ventricular assist device. Results- We identified 7848 patients with heart failure awaiting heart transplantation, of whom 1068 (13.6%) underwent heart transplantation. During a mean follow-up of 2.7 years, we identified 428 strokes. The annual incidence of stroke was 0.7% (95% CI, 0.5%-1.0%) after heart transplantation versus 2.4% (95% CI, 2.2%-2.6%) among those awaiting heart transplantation. After adjustment for potential confounders, heart transplantation was associated with a lower risk of stroke (hazard ratio, 0.4; 95% CI, 0.2-0.6). Conclusions- Heart transplantation is associated with a decreased risk of stroke among patients with heart failure awaiting transplantation.
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Affiliation(s)
- Alexander E Merkler
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Feil Family Brain and Mind Research Institute, Department of Neurology (A.E.M., S.B.M., B.B.N., C.I., H.K.)
| | - Monica L Chen
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.)
| | - Neal S Parikh
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Department of Neurology, Columbia College of Physicians and Surgeons, New York, NY (N.S.P.)
| | - Santosh B Murthy
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Feil Family Brain and Mind Research Institute, Department of Neurology (A.E.M., S.B.M., B.B.N., C.I., H.K.)
| | - Shadi Yaghi
- Department of Neurology, Warren Alpert Medical School of Brown University, Providence, RI (S.Y.)
| | - Parag Goyal
- Department of Cardiology, Weill Cornell Medical College, New York, NY (P.G., P.M.O., M.G.K.)
| | - Peter M Okin
- Department of Cardiology, Weill Cornell Medical College, New York, NY (P.G., P.M.O., M.G.K.)
| | - Maria G Karas
- Department of Cardiology, Weill Cornell Medical College, New York, NY (P.G., P.M.O., M.G.K.)
| | - Babak B Navi
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Feil Family Brain and Mind Research Institute, Department of Neurology (A.E.M., S.B.M., B.B.N., C.I., H.K.)
| | - Costantino Iadecola
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Feil Family Brain and Mind Research Institute, Department of Neurology (A.E.M., S.B.M., B.B.N., C.I., H.K.)
| | - Hooman Kamel
- From the Clinical and Translational Neuroscience Unit (A.E.M., M.L.C., N.S.P., S.B.M., B.B.N., C.I., H.K.).,Feil Family Brain and Mind Research Institute, Department of Neurology (A.E.M., S.B.M., B.B.N., C.I., H.K.)
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Rebholz M, Dual S, Batliner M, Meboldt M, Schmid Daners M. Short-term physiological response to high-frequency-actuated pVAD support. Artif Organs 2019; 43:1170-1181. [PMID: 31211873 DOI: 10.1111/aor.13521] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/29/2019] [Accepted: 06/07/2019] [Indexed: 01/04/2023]
Abstract
Ventricular assist devices (VADs) are an established treatment option for heart failure (HF). However, the devices are often plagued by material-related hemocompatibility issues. In contrast to continuous flow VADs with high shear stresses, pulsatile VADs (pVADs) offer the potential for an endothelial cell coating that promises to prevent many adverse events caused by an insufficient hemocompatibility. However, their size and weight often precludes their intracorporeal implantation. A reduction of the pump body size and weight of the pump could be achieved by an increase in the stroke frequency while maintaining a similar cardiac output. We present a new pVAD system consisting of a pump and an actuator specifically designed for actuation frequencies of up to 240 bpm. In vitro and in vivo results of the short-term reaction of the cardiovascular system show no significant changes in left ventricular and aortic pressure between actuation frequencies from 60 to 240 bpm. The aortic pulsatility increases when the actuation frequency is raised while the heart rate remains unaffected in vivo. These results lead us to the conclusion that the cardiovascular system tolerates short-term increases of the pVAD stroke frequencies.
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Affiliation(s)
- Mathias Rebholz
- Product Development Group Zurich, ETH Zurich, Zurich, Switzerland
| | - Seraina Dual
- Product Development Group Zurich, ETH Zurich, Zurich, Switzerland
| | - Martin Batliner
- Product Development Group Zurich, ETH Zurich, Zurich, Switzerland
| | - Mirko Meboldt
- Product Development Group Zurich, ETH Zurich, Zurich, Switzerland
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16
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Nurses' Competence Caring for Hospitalized Patients With Ventricular Assist Devices. Dimens Crit Care Nurs 2019; 38:38-49. [PMID: 30499791 DOI: 10.1097/dcc.0000000000000332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Nursing care is an essential component of the delivery of high-quality patient care for advanced heart failure patients with ventricular assist devices (VADs). However, there is little information about how VAD patient care competence is formed, and there are no empirical data regarding the bed nurses' competence. OBJECTIVES The aim of this study was to explain how nurses perceived their competence related to VAD technology and how they utilized resources to equip themselves for the management of patients with implantable VADs. METHODS An exploratory correlational research design was used in this study. Online surveys including demographic and work characteristics questionnaires as well as VAD Innovation in Nursing Appraisal Scale (knowledge, adoption, and communication) were completed by 237 critical-care unit and progressive care unit (PCU) nurses. RESULTS Ventricular assist device knowledge, adoption, and communication of innovation mean scores were 3.9 ± 0.6, 3.9 ± 0.8, and 3.7 ± 0.9, respectively, indicating moderate/high levels. Critical-care unit nurses reported higher levels of knowledge (3.7 vs 3.6) and adoption (4.0 vs 3.8; P < .05) of innovation than did the PCU nurses, with no differences in communication. Compared with PCU nurses, critical-care unit nurses were more likely to seek VAD competence-related information using mass media. Innovation and adoption were associated with years of nursing experience and some hospital characteristics. CONCLUSION Critical-care unit nurses have higher self-reported VAD care competence than PCU nurses. Further research is needed to confirm the findings and link nurse competence with VAD patient outcomes.
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17
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Young JB, Vest AR. Is There a Sweet Spot for Left Ventricular Assist Devices and Diabetes Mellitus? Circ Heart Fail 2019; 10:CIRCHEARTFAILURE.117.004594. [PMID: 29141861 DOI: 10.1161/circheartfailure.117.004594] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- James B Young
- From the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, the Kaufman Center for Heart Failure, and the Endocrinology and Metabolism and Heart and Vascular Institutes of the Cleveland Clinic, OH (J.B.Y.); and the Division of Cardiology, The CardioVascular Center, Tufts Medical Center, Boston, MA (A.V.).
| | - Amanda R Vest
- From the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, the Kaufman Center for Heart Failure, and the Endocrinology and Metabolism and Heart and Vascular Institutes of the Cleveland Clinic, OH (J.B.Y.); and the Division of Cardiology, The CardioVascular Center, Tufts Medical Center, Boston, MA (A.V.)
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18
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Patel N, Gluck JA, Radojevic J, Coleman CI, Baker WL. Left ventricular assist device implantation improves glycaemic control: a systematic review and meta-analysis. ESC Heart Fail 2018; 5:1141-1149. [PMID: 30052326 PMCID: PMC6300809 DOI: 10.1002/ehf2.12337] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/15/2018] [Accepted: 06/22/2018] [Indexed: 01/08/2023] Open
Abstract
AIMS Heart failure (HF) and diabetes mellitus (DM) often coexist and have bidirectional association. Advanced HF is associated with worsened glycaemic control. This meta-analysis investigated the effects of left ventricular assist device (LVAD) implantation on markers of DM control. METHODS AND RESULTS We performed a systematic search of MEDLINE and Cochrane through October 2017 to identify studies evaluating advanced HF patients who had received an LVAD and reported markers of glycaemic control. The primary outcome was glycosylated haemoglobin A1c (HbA1c), and the secondary outcomes included fasting glucose, daily insulin requirements, and body mass index (BMI). Outcomes were pooled using a Hartung-Knapp random-effects model producing a mean difference (MD) and 95% confidence interval (CI). Thirteen studies, including 820 participants, were included. HbA1c was 1.23% lower following LVAD implantation (95% CI -1.49 to -0.98). Greater HbA1c reductions were seen with higher pre-LVAD values. Similarly, fasting plasma glucose (-24.4 mg/dL, 95% CI -33.4 to -15.5), daily insulin requirements (-18.8 units, 95% CI -28.8 to -8.7), and serum creatinine levels (MD -0.20, 95% CI -0.35 to -0.06) were significantly lower than pre-LVAD levels. We saw no difference in BMI (MD 0.09, 95% CI -1.24 to 1.42). CONCLUSIONS LVAD implantation was associated with significant improvement in HbA1c, fasting plasma glucose, and daily insulin need in advanced HF patients.
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Affiliation(s)
- Nirav Patel
- Center for Advanced Heart Failure & Pulmonary Vascular Disease, Department of CardiologyHartford HospitalHartfordCTUSA
| | - Jason A. Gluck
- Center for Advanced Heart Failure & Pulmonary Vascular Disease, Department of CardiologyHartford HospitalHartfordCTUSA
| | - Joseph Radojevic
- Center for Advanced Heart Failure & Pulmonary Vascular Disease, Department of CardiologyHartford HospitalHartfordCTUSA
| | - Craig I. Coleman
- Department of Pharmacy PracticeUniversity of Connecticut School of Pharmacy69 N. Eagleville Rd, Unit 3092StorrsCT06269‐3092USA
| | - William L. Baker
- Department of Pharmacy PracticeUniversity of Connecticut School of Pharmacy69 N. Eagleville Rd, Unit 3092StorrsCT06269‐3092USA
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Kanwar MK, Bailey S, Murali S. Challenges and Future Directions in Left Ventricular Assist Device Therapy. Crit Care Clin 2018; 34:479-492. [PMID: 29907278 DOI: 10.1016/j.ccc.2018.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
The clinical use of left ventricular assist devices (LVADs) in the growing epidemic of heart failure has improved quality of life and long-term survival for this otherwise devastating disease. The current generation of commercially available devices offers a smaller profile that simplifies surgical implantation, a design that optimizes blood flow characteristics, with less adverse events and improved durability than their predecessors. Despite this, the risk for adverse events remains significant, as do burdens for patients and their caregivers. Appropriate patient selection remains key to optimal LVAD outcomes.
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Affiliation(s)
- Manreet K Kanwar
- Section of Heart Failure/Transplant/MCS and Pulmonary Hypertension, Cardiovascular Institute, Allegheny Health Network, Temple University School of Medicine, 320 East North Avenue, 16th Floor ST, Pittsburgh, PA 15212, USA.
| | - Stephen Bailey
- Department of Cardiothoracic Surgery, Cardiovascular Institute, Allegheny Health Network, 320 East North Avenue, Pittsburgh, PA 15212, USA
| | - Srinivas Murali
- Department of Cardiothoracic Surgery, Cardiovascular Institute, Allegheny Health Network, 320 East North Avenue, Pittsburgh, PA 15212, USA
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21
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Management of Patients on Mechanical Circulatory Assist Devices During Noncardiac Surgery. Int Anesthesiol Clin 2018; 56:e1-e27. [PMID: 30204602 DOI: 10.1097/aia.0000000000000205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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3D Printing of Functional Assemblies with Integrated Polymer-Bonded Magnets Demonstrated with a Prototype of a Rotary Blood Pump. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8081275] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Conventional magnet manufacturing is a significant bottleneck in the development processes of products that use magnets, because every design adaption requires production steps with long lead times. Additive manufacturing of magnetic components delivers the opportunity to shift to agile and test-driven development in early prototyping stages, as well as new possibilities for complex designs. In an effort to simplify integration of magnetic components, the current work presents a method to directly print polymer-bonded hard magnets of arbitrary shape into thermoplastic parts by fused deposition modeling. This method was applied to an early prototype design of a rotary blood pump with magnetic bearing and magnetic drive coupling. Thermoplastics were compounded with 56 vol.% isotropic NdFeB powder to manufacture printable filament. With a powder loading of 56 vol.%, remanences of 350 mT and adequate mechanical flexibility for robust processability were achieved. This compound allowed us to print a prototype of a turbodynamic pump with integrated magnets in the impeller and housing in one piece on a low-cost, end-user 3D printer. Then, the magnetic components in the printed pump were fully magnetized in a pulsed Bitter coil. The pump impeller is driven by magnetic coupling to non-printed permanent magnets rotated by a brushless DC motor, resulting in a flow rate of 3 L/min at 1000 rpm. For the first time, an application of combined multi-material and magnet printing by fused deposition modeling was shown. The presented process significantly simplifies the prototyping of products that use magnets, such as rotary blood pumps, and opens the door for more complex and innovative designs. It will also help postpone the shift to conventional manufacturing methods to later phases of the development process.
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Racca V, Castiglioni P, Panzarino C, Saresella M, Marventano I, Verde A, Oliva F, Ferratini M. Differences in biochemical markers between Heart-transplanted and Left Ventricular Assist Device implanted patients, during cardiac rehabilitation. Sci Rep 2018; 8:10816. [PMID: 30018333 PMCID: PMC6050285 DOI: 10.1038/s41598-018-29193-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 07/02/2018] [Indexed: 12/03/2022] Open
Abstract
Heart transplant (HTx) and left ventricular assist device (LVAD) implant are the best options for symptomatic end stage heart failure, but LVAD patients show lower rehabilitative outcome than HTx patients. To investigate the causes, we compared biomarkers levels and their association with rehabilitative outcome in 51 HTx and in 46 LVAD patients entering the same cardiac rehabilitation program. In both groups, routine biomarkers were measured at start (T1) and end (T2) of cardiac rehabilitation while homocysteine, leptine and IGF-1 were measured at T1 only. HTx patients had lower lymphocyte, platelets, glucose, total proteins and albumin at T1; differences with LVAD patients vanished during rehabilitation when new cases of diabetes were observed in HTx. By contrast, total cholesterol, LDL and HDL fractions, leptin and IGF-1 were higher in HTx patients. The increase from T1 to T2 in six-minute walking test distance, measure of functional rehabilitation outcome, was positively associated with homocysteine and IGF-1 levels in HTx patients. In conclusion, during rehabilitation care should be paid to the early occurrence of dyslipidemia and hyperglycemia in HTx patients, which also require a proper protein dietary support. IGF-1, dangerously low in LVAD patients, might contribute to their lower rehabilitative outcome.
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Affiliation(s)
- Vittorio Racca
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Cardiology Rehabilitation Department, Milan, 20148, Italy.
| | - Paolo Castiglioni
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Biomedical Technology Department, Milan, 20148, Italy
| | - Claudia Panzarino
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Cardiology Rehabilitation Department, Milan, 20148, Italy
| | - Marina Saresella
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Laboratory of Molecular Medicine and Biotechnology, Milan, 20148, Italy
| | - Ivana Marventano
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Laboratory of Molecular Medicine and Biotechnology, Milan, 20148, Italy
| | - Alessandro Verde
- Niguarda Hospital, De Gasperis Cardio Center, Milan, 20162, Italy
| | - Fabrizio Oliva
- Niguarda Hospital, De Gasperis Cardio Center, Milan, 20162, Italy
| | - Maurizio Ferratini
- Santa Maria Nascente Institute IRCCS, Don Gnocchi Foundation, Cardiology Rehabilitation Department, Milan, 20148, Italy
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Westerhof BE, Saouti N, van der Laarse WJ, Westerhof N, Vonk Noordegraaf A. Treatment strategies for the right heart in pulmonary hypertension. Cardiovasc Res 2018; 113:1465-1473. [PMID: 28957540 PMCID: PMC5852547 DOI: 10.1093/cvr/cvx148] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/01/2017] [Indexed: 02/06/2023] Open
Abstract
The function of the right ventricle (RV) determines the prognosis of patients with pulmonary hypertension. While much progress has been made in the treatment of pulmonary hypertension, therapies for the RV are less well established. In this review of treatment strategies for the RV, first we focus on ways to reduce wall stress since this is the main determinant of changes to the ventricle. Secondly, we discuss treatment strategies targeting the detrimental consequences of increased RV wall stress. To reduce wall stress, afterload reduction is the essential. Additionally, preload to the ventricle can be reduced by diuretics, by atrial septostomy, and potentially by mechanical ventricular support. Secondary to ventricular wall stress, left-to-right asynchrony, altered myocardial energy metabolism, and neurohumoral activation will occur. These may be targeted by optimising RV contraction with pacing, by iron supplement, by angiogenesis and improving mitochondrial function, and by neurohumoral modulation, respectively. We conclude that several treatment strategies for the right heart are available; however, evidence is still limited and further research is needed before clinical application can be recommended.
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Affiliation(s)
- Berend E Westerhof
- Department of Pulmonary Diseases, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.,Department of Medical Biology, Academic Medical Center, Amsterdam, The Netherlands
| | - Nabil Saouti
- Department of Cardio-Thoracic Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Willem J van der Laarse
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Nico Westerhof
- Department of Pulmonary Diseases, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Anton Vonk Noordegraaf
- Department of Pulmonary Diseases, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
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Bozkurt S. Effect of Cerebral Flow Autoregulation Function on Cerebral Flow Rate Under Continuous Flow Left Ventricular Assist Device Support. Artif Organs 2018; 42:800-813. [DOI: 10.1111/aor.13148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/13/2018] [Accepted: 02/20/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Selim Bozkurt
- University College London - Institute of Cardiovascular Science; London United Kingdom of Great Britain and Northern Ireland
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Young JB. Long-Term Mechanical Circulatory Support vs Heart Transplant: A Half-Century of Progress, but When Will the Tin Man Arrive? J Card Fail 2018; 24:330-334. [PMID: 29499320 DOI: 10.1016/j.cardfail.2018.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 02/06/2018] [Accepted: 02/13/2018] [Indexed: 01/26/2023]
Affiliation(s)
- James B Young
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Endocrinology & Metabolism Institute George & Linda Kaufman Chair, Heart & Vascular Institute Cleveland Clinic, Cleveland, Ohio.
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Racca V, Castiglioni P, Panzarino C, Oliva F, Perna E, Ferratini M. End-stage heart failure: Two surgical approaches with different rehabilitative outcomes. PLoS One 2017; 12:e0185717. [PMID: 28972991 PMCID: PMC5626463 DOI: 10.1371/journal.pone.0185717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 09/18/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND A rising number of patients are surgically treated for heart failure at the more advanced stage, thanks to the increasing use of left ventricular assist device (LVAD) as a reliable alternative to heart transplantation (HTx). However, it is still unknown whether differences exist between the two surgical approaches in the efficacy of rehabilitation programmes. Therefore, aim of this study was to evaluate whether functional capacity and rehabilitative outcomes differ between HTx and implantation of LVAD. METHODS AND RESULTS We enrolled 51 patients with HTx and 46 with LVAD upon admission to our rehabilitation-unit. We evaluated six-minute walking test (6MWT), resting oxygen saturation (SaO2) and nutritional assessment before and after a standardised cardiovascular rehabilitation programme. HTx and LVAD groups differed in age, anthropometric variables, gender distribution. Upon enrolment, 6MWT distance was similar in the two groups, whereas malnutrition was less frequent and the waist circumference/height ratio (WHtR) was greater in LVAD patients. SaO2 was greater in HTx patients. Rehabilitation improved SaO2, 6MWT distance and nutritional status. The difference in malnutrition disappeared, but WHtR remained higher in the LVAD and SaO2 higher in the HTx patients; the 6MWT distance improved more in the HTx patients. Multivariate linear regression analysis confirmed that the type of intervention was independent predictor of 6MWT distance after rehabilitation. CONCLUSIONS HTx patients improve more rapidly and perform better after rehabilitation, suggesting the need for more tailored rehabilitation training for LVAD patients.
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Affiliation(s)
- Vittorio Racca
- Cardiology Rehabilitation Center – Santa Maria Nascente Institute IRCCS, Don C. Gnocchi Foundation, Milan, Italy
- * E-mail:
| | - Paolo Castiglioni
- Biomedical Technology Department – Santa Maria Nascente Institute IRCCS, Don C. Gnocchi Foundation, Milan, Italy
| | - Claudia Panzarino
- Cardiology Rehabilitation Center – Santa Maria Nascente Institute IRCCS, Don C. Gnocchi Foundation, Milan, Italy
| | - Fabrizio Oliva
- De Gasperis Cardio Center, Niguarda Hospital, Milan, Italy
| | - Enrico Perna
- De Gasperis Cardio Center, Niguarda Hospital, Milan, Italy
| | - Maurizio Ferratini
- Cardiology Rehabilitation Center – Santa Maria Nascente Institute IRCCS, Don C. Gnocchi Foundation, Milan, Italy
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Lund LH, Trochu JN, Meyns B, Caliskan K, Shaw S, Schmitto JD, Schibilsky D, Damme L, Heatley J, Gustafsson F. Screening for heart transplantation and left ventricular assist system: results from the ScrEEning for advanced Heart Failure treatment (SEE-HF) study. Eur J Heart Fail 2017; 20:152-160. [PMID: 28960673 DOI: 10.1002/ejhf.975] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 07/22/2017] [Accepted: 07/25/2017] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Heart transplantation (HTx) and implantable left ventricular assist systems (LVAS) improve outcomes in advanced heart failure but may be underutilized. We hypothesized that screening can identify appropriate candidates. METHODS AND RESULTS The ScrEEning for advanced Heart Failure treatment (SEE-HF) study was a multicentre prospective study screening patients with existing cardiac resynchronization therapy (CRT) and/or implantable cardioverter-defibrillator (ICD) for ejection fraction ≤40% and New York Heart Association (NYHA) class III-IV, and subsequently for guideline-based HTx and LVAS indication. Of 1722 (mean age 64 ± 14 years, 26% women) patients screened at eight centres in seven European countries, 121 (7.0%) were eligible and 99 (5.7%; mean age 61 ± 10 years, 19% women) patients were enrolled for detailed assessment. Twenty-six of the 99 enrolled patients (26%) were eligible for either HTx or LVAD (18 eligible for HTx; 7 eligible for LVAD; and 1 eligible for both). Eleven patients were listed for HTx and three received an LVAS. Eligible patients were 61 ± 8 years and 19% women, whereas those actually receiving intervention were 56 ± 8 years and 8% women. CONCLUSIONS Among patients with CRT and/or ICD, a minority have NYHA class III-IV heart failure and ejection fraction ≤40%. Among these, however, more than one-quarter have an unrecognized need for HTx or LVAS. When patients are offered intervention based on screening, many decline. Discrepancies exist between clinical and patient equipoise. Clinical Trial Registration ClinicalTrials.gov Unique Identifier: NCT00894387.
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Affiliation(s)
- Lars H Lund
- Department of Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden
| | - Jean-Noel Trochu
- Institut du Thorax, Inserm UMR 1087-CIC1413, Centre Hospitalier Universaire de Nantes, Nantes, France
| | | | - Kadir Caliskan
- Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Steven Shaw
- University Hospital of S. Manchester NHS Trust, Manchester, UK
| | - Jan D Schmitto
- Department of Cardiac, Thoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - David Schibilsky
- German Heart Competance Center, University Clinical Center Tuebingen, Tuebingen, Germany
| | | | | | - Finn Gustafsson
- Department of Cardiology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
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29
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Hosseinipour M, Gupta R, Bonnell M, Elahinia M. Rotary mechanical circulatory support systems. J Rehabil Assist Technol Eng 2017; 4:2055668317725994. [PMID: 31186935 PMCID: PMC6453075 DOI: 10.1177/2055668317725994] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 07/20/2017] [Indexed: 12/25/2022] Open
Abstract
A detailed survey of the current trends and recent advances in rotary mechanical
circulatory support systems is presented in this paper. Rather than clinical reports, the
focus is on technological aspects of these rehabilitating devices as a reference for
engineers and biomedical researchers. Existing trends in flow regimes, flow control, and
bearing mechanisms are summarized. System specifications and applications of the most
prominent continuous-flow ventricular assistive devices are provided. Based on the flow
regime, pumps are categorized as axial flow, centrifugal flow, and mixed flow. Unique
characteristics of each system are unveiled through an examination of the structure,
bearing mechanism, impeller design, flow rate, and biocompatibility. A discussion on the
current limitations is provided to invite more studies and further improvements.
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Affiliation(s)
- Milad Hosseinipour
- Dynamic and Smart Systems Laboratory, The University of Toledo, Toledo, OH, USA.,Department of Mechanical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Rajesh Gupta
- Cardiovascular Medicine Division, The University of Toledo Medical Center, Toledo, OH, USA
| | - Mark Bonnell
- Cardiothoracic Surgery Division, The University of Toledo Medical Center, Toledo, OH, USA
| | - Mohammad Elahinia
- Dynamic and Smart Systems Laboratory, The University of Toledo, Toledo, OH, USA
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30
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Raia F, Deng MC. Artificial heart pumps: bridging the gap between science, technology and personalized medicine by relational medicine. Future Cardiol 2016; 13:23-32. [PMID: 27990844 DOI: 10.2217/fca-2016-0020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the US population of 300 million, 3 million have heart failure with reduced ejection fraction and 300,000 have advanced heart failure. Long-term mechanical circulatory support will, within the next decade, be recommended to 30,000 patients annually in the USA, 3000 undergo heart transplantation annually. What do these advances mean for persons suffering from advanced heart failure and their loved ones/caregivers? In this perspective article, we discuss - by exemplifying a case report of a 27-year-old man receiving a Total Artificial Heart - a practice concept of modern medicine that fully incorporates the patient's personhood perspective which we have termed Relational Medicine™. From this case study, it becomes apparent that the successful practice of modern cardiovascular medicine requires the person-person encounter as a core practice element.
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Affiliation(s)
- Federica Raia
- Graduate School of Education & Information Studies & David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Mario C Deng
- Graduate School of Education & Information Studies & David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
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31
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Lüscher TF. Catheter-based and surgical interventions in cardiac and aortic conditions. Eur Heart J 2016; 37:3421-3424. [PMID: 28039217 DOI: 10.1093/eurheartj/ehw624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Thomas F Lüscher
- Editor-in-Chief, Zurich Heart House, Careum Campus, Moussonstrasse 4, 8091 Zurich, Switzerland
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