1
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Denardo SJ, Vlachos PP, Meyers BA, Babakhani-Galangashi R, Wang L, Gao Z, Tcheng JE. Translating proof-of-concept for platelet slip into improved antithrombotic therapeutic regimens. Platelets 2024; 35:2353582. [PMID: 38773939 DOI: 10.1080/09537104.2024.2353582] [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: 01/22/2024] [Accepted: 05/03/2024] [Indexed: 05/24/2024]
Abstract
Platelets are central to thrombosis. Research at the intersection of biological and physical sciences provides proof-of-concept for shear rate-dependent platelet slip at vascular stenosis and near device surfaces. Platelet slip extends the observed biological "slip-bonds" to the boundary of functional gliding without contact. As a result, there is diminished engagement of the coagulation cascade by platelets at these surfaces. Comprehending platelet slip would more precisely direct antithrombotic regimens for different shear environments, including for percutaneous coronary intervention (PCI). In this brief report we promote translation of the proof-of-concept for platelet slip into improved antithrombotic regimens by: (1) reviewing new supporting basic biological science and clinical research for platelet slip; (2) hypothesizing the principal variables that affect platelet slip; (3) applying the consequent construct model in support of-and in some cases to challenge-relevant contemporary guidelines and their foundations (including for urgent, higher-risk PCI); and (4) suggesting future research pathways (both basic and clinical). Should future research demonstrate, explain and control platelet slip, then a paradigm shift for choosing and recommending antithrombotic regimens based on predicted shear rate should follow. Improved clinical outcomes with decreased complications accompanying this paradigm shift for higher-risk PCI would also result in substantive cost savings.
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Affiliation(s)
- Scott J Denardo
- Medicine/Cardiology, Duke University Medical Center, Durham, NC, USA
| | - Pavlos P Vlachos
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Brett A Meyers
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | | | - Lin Wang
- Department of Statistics, Purdue University, West Lafayette, IN, USA
| | - Zejin Gao
- Department of Statistics, Purdue University, West Lafayette, IN, USA
| | - James E Tcheng
- Medicine/Cardiology, Duke University Medical Center, Durham, NC, USA
- Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA
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2
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Hahne M, Crone V, Thomas I, Wolfgramm C, Liedtke FKP, Wurm FH, Torner B. Interaction of a Ventricular Assist Device With Patient-Specific Cardiovascular Systems: In-Silico Study With Bidirectional Coupling. ASAIO J 2024; 70:832-840. [PMID: 38551498 PMCID: PMC11426988 DOI: 10.1097/mat.0000000000002181] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2024] Open
Abstract
Ventricular assist devices (VADs) are used to assist the heart function of patients with advanced heart failure. Computational fluid dynamics in VADs are widely applied in the development and optimization, for example, to evaluate blood damage. For these simulations, the pulsating operating conditions, in which the VAD operates, should be included accurately. Therefore, this study aims to evaluate the flow in a VAD by interacting with patient-specific cardiovascular systems of heart failure patients. A numeric method will be presented, which includes a patient-specific cardiovascular system model that is bidirectionally coupled with a three-dimensional (3D) flow simulation of the HeartMate 3. The cardiovascular system is represented by a lumped parameter model. Three heart failure patients are considered, based on clinical data from end-stage heart failure patients. Various parameters of the cardiovascular system and the VAD are analyzed, for example, flow rates, pressures, VAD heads, and efficiencies. A further important parameter is the blood damage potential of the VAD, which varies significantly among different patients. Moreover, the predicted blood damage fluctuates within a single heartbeat. The increase in blood damage is evaluated based on the operating conditions. Both, overload and especially partial load conditions during the pulsating operation result in elevated blood damage.
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Affiliation(s)
- Mario Hahne
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
| | - Vincenz Crone
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
| | - Inga Thomas
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
| | - Calvin Wolfgramm
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
| | | | - Frank-Hendrik Wurm
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
| | - Benjamin Torner
- From the Institute of Turbomachinery, University of Rostock, Rostock, Germany
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3
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Bornoff J, Zaman SF, Najar A, Finocchiaro T, Perkins IL, Cookson AN, Fraser KH. Assessment of haemolysis models for a positive-displacement total artificial heart. Int J Artif Organs 2024:3913988241267797. [PMID: 39297328 DOI: 10.1177/03913988241267797] [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: 10/04/2024]
Abstract
The assessment and reduction of haemolysis within mechanical circulatory support (MCS) remains a concern with regard to device safety and regulatory approval. Numerical methods for predicting haemolysis have typically been applied to rotary MCS devices and the extent to which these methods apply to positive-displacement MCS is unclear. The aim of this study was to evaluate the suitability of these methods for assessing haemolysis in positive-displacement blood pumps. Eulerian scalar-transport and Lagrangian particle-tracking approaches derived from the shear-based power-law relationship were used to calculate haemolysis in a computational fluid dynamics model of the Realheart total artificial heart. A range of power-law constants and their effect on simulated haemolysis were also investigated. Both Eulerian and Lagrangian methods identified the same key mechanism of haemolysis: leakage flow through the bileaflet valves. Whilst the magnitude of haemolysis varied with different power-law constants, the method of haemolysis generation remained consistent. The Eulerian method was more robust and reliable at identifying sites of haemolysis generation, as it was able to capture the persistent leakage flow throughout the entire pumping cycle. This study paves the way for different positive-displacement MCS devices to be compared across different operating conditions, enabling the optimisation of these pumps for improved patient outcomes.
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Affiliation(s)
- Joseph Bornoff
- Department of Mechanical Engineering, University of Bath, Bath, UK
- Centre for Bioengineering & Biomedical Technologies, University of Bath, UK
| | | | - Azad Najar
- Scandinavian Real Heart AB, Västerås, Sweden
| | | | | | - Andrew N Cookson
- Department of Mechanical Engineering, University of Bath, Bath, UK
- Centre for Bioengineering & Biomedical Technologies, University of Bath, UK
| | - Katharine H Fraser
- Department of Mechanical Engineering, University of Bath, Bath, UK
- Centre for Bioengineering & Biomedical Technologies, University of Bath, UK
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4
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Palazzolo TC, Sarkisyan H, Matlis GC, McGowan J, Tchantchaleishvili V, Stevens RM, Throckmorton AL. Series Multiblood Pump Design With Dual Activation for Pediatric Patients With Heart Failure. ASAIO J 2024:00002480-990000000-00553. [PMID: 39255348 DOI: 10.1097/mat.0000000000002300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024] Open
Abstract
The translational development of pediatric ventricular assist devices (VADs) lags years behind adult device options, negatively impacting pediatric patient outcomes. To address this need, we are developing a novel, series-flow, double-blood pump VAD that integrates an axial and centrifugal pump into a single device. The axial pump is used for initial circulatory assistance in younger patients; then, an internal activation mechanism triggers the centrifugal pump to activate in line with the axial pump, providing additional pressure and flow to match pediatric patient growth cycles. Here, we focused on the design and improvement of the device flow paths through computational analysis and in vitro hydraulic testing of a prototype. We estimated pressure-flow generation, fluid scalar stresses, and blood damage levels. In vitro hydraulic tests correlated well with shear stress transport (SST) predictions, with an average deviation of 4.5% for the complex, combined flow path. All data followed expected pump performance trends. The device exceeded target levels for blood damage in the blade tip clearances, and this must be both investigated and addressed in the next design phase. These study findings establish a strong foundation for the future development of the Drexel Double-Dragon VAD.
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Affiliation(s)
- Thomas C Palazzolo
- From the BioCirc Research Laboratory, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania
| | - Harutyun Sarkisyan
- From the BioCirc Research Laboratory, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania
| | - Giselle C Matlis
- From the BioCirc Research Laboratory, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania
| | - Jordon McGowan
- From the BioCirc Research Laboratory, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania
| | | | - Randy M Stevens
- Department of Pediatrics, Pediatric Cardiac Surgery, College of Medicine, St. Christopher's Hospital for Children, Drexel University, Philadelphia, Pennsylvania
| | - Amy L Throckmorton
- From the BioCirc Research Laboratory, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania
- Department of Pediatrics, Pediatric Cardiac Surgery, College of Medicine, St. Christopher's Hospital for Children, Drexel University, Philadelphia, Pennsylvania
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5
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Ucak K, Karatas F, Cetinkaya E, Pekkan K. Synchronous PIV measurements of a self-powered blood turbine and pump couple for right ventricle support. Sci Rep 2024; 14:19962. [PMID: 39198487 PMCID: PMC11358467 DOI: 10.1038/s41598-024-70243-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 08/14/2024] [Indexed: 09/01/2024] Open
Abstract
A blood turbine-pump system (iATVA), resembling a turbocharger was proposed as a mechanical right-heart assist device without external drive power. In this study, the iATVA system is investigated with particular emphasis on the blood turbine flow dynamics. A time-resolved 2D particle image velocimetry (PIV) set-up equipped with a beam splitter and two high speed cameras, allowed simultaneous recordings from both the turbine and pump impellers at 7 different phased-locked instances. The iATVA prototype is 3D printed using an optically clear resin following our earlier PIV protocols. Results showed that magnetically coupled impellers operated synchronously. As the turbine flow rate increased from 1.6 to 2.4 LPM, the rotational speed and relative inlet flow angle increase from 630 to 900 rpm, and 38 to 55% respectively. At the trailing edges, backflow region spanned 3/5 of the total passage outlet flow, and an extra leakage flow was observed at the leading edge. For this early turbine design, approximately, 75% of the turbine blade passage was not contributing to the impulse operation mode. The maximum non-wall shear rate was ~ 2288 s-1 near to the inlet exit, which is significantly lower than the commercial blood pumps, encouraging further research and blood experiments of this novel concept. Experimental results will improve the hydrodynamic design of the turbine impeller and volute regions and will be useful in computational fluid dynamics validation studies of similar passive devices.
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Affiliation(s)
- Kagan Ucak
- Mechanical Engineering Department, Koç University, Rumeli Feneri Kampüsü, Sarıyer, Istanbul, 34450, Turkey
| | - Faruk Karatas
- Mechanical Engineering Department, Koç University, Rumeli Feneri Kampüsü, Sarıyer, Istanbul, 34450, Turkey
| | - Emre Cetinkaya
- Mechanical Engineering, Yildiz Technical University, Istanbul, Turkey
| | - Kerem Pekkan
- Mechanical Engineering Department, Koç University, Rumeli Feneri Kampüsü, Sarıyer, Istanbul, 34450, Turkey.
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6
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Cikes M, Yuzefpolskaya M, Gustafsson F, Mehra MR. Antithrombotic Strategies With Left Ventricular Assist Devices. J Card Fail 2024:S1071-9164(24)00318-X. [PMID: 39154903 DOI: 10.1016/j.cardfail.2024.07.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2024] [Accepted: 07/19/2024] [Indexed: 08/20/2024]
Abstract
Long-term outcomes of patients with advanced heart failure treated with durable left ventricular assist devices (LVADs) have been augmented due to improved durability and hemocompatibility on the backbone of pump engineering enhancements. The incidence of hemocompatibility-related adverse events (pump thrombosis, stroke and nonsurgical bleeding events) are device specific and vary by type of engineered pump. A fully magnetically levitated rotor containing LVAD in concert with use of antithrombotic therapy has successfully overcome an increased risk of pump thrombosis and stroke-risk, albeit with only modest reduction in bleeding events. Modifications to antithrombotic strategies have focused on reduced-dose vitamin K antagonist use or use of direct oral anticoagulants with demonstration of safety and progress in reduction of mucosal bleeding episodes with elimination of antiplatelet agents. This review outlines the current landscape of advances in anticoagulation management in LVAD patients, highlighting the need for ongoing research and cautious application of emerging therapies and technologies.
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Affiliation(s)
- Maja Cikes
- Department of Cardiovascular Diseases, University of Zagreb School of Medicine, University Hospital Center Zagreb, Zagreb, Croatia
| | - Melana Yuzefpolskaya
- Department of Cardiology, New York Presbyterian Hospital, Columbia University, New York, New York
| | - Finn Gustafsson
- Department of Cardiology, Rigshospitalet, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Mandeep R Mehra
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
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7
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Ripoll JG, Orjuela RB, Ortoleva J, Nabzdyk CS, Dasani S, Bhowmik S, Balakrishna A, Hain S, Chang MG, Bittner EA, Ramakrishna H. HeartMate 3: Analysis of Outcomes and Future Directions. J Cardiothorac Vasc Anesth 2024:S1053-0770(24)00531-7. [PMID: 39214797 DOI: 10.1053/j.jvca.2024.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2024] [Accepted: 08/07/2024] [Indexed: 09/04/2024]
Abstract
Heart failure (HF) remains a public health concern affecting millions of individuals worldwide. Despite recent advances in device-related therapies, the prognosis for patients with chronic HF remains poor with significant long-term risk of morbidity and mortality. Left ventricular assist devices (LVADs) have transformed the landscape of advanced HF management, offering circulatory support as destination therapy or as a bridge for heart transplantation. Among the latest generation of LVADs, the HeartMate 3 has gained popularity due to improved clinical outcomes and lower risk of serious adverse events when compared with previous similar devices. The ELEVATE (Evaluating the HeartMate 3 with Full MagLev Technology in a Post-Market Approval Setting) Registry and the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) trial represent landmark investigations into the performance and comparative effectiveness of the HeartMate 3 LVAD. This review provides a comprehensive synthesis of the safety and efficacy of the 2-year and 5-year HeartMate LVAD outcomes, highlighting key findings, methodological considerations, implications for clinical practice, and future directions.
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Affiliation(s)
- Juan G Ripoll
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN
| | | | - Jamel Ortoleva
- Department of Anesthesiology, Boston Medical Center, Boston, MA
| | - Christoph S Nabzdyk
- Department of Anesthesiology, Pain and Perioperative Medicine, Brigham and Women's Hospital, Boston, MA
| | - Serena Dasani
- Department of Anesthesiology, Pain and Perioperative Medicine, Brigham and Women's Hospital, Boston, MA
| | - Subasish Bhowmik
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN
| | - Aditi Balakrishna
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN
| | - Stephan Hain
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Marvin G Chang
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Edward A Bittner
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA
| | - Harish Ramakrishna
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN.
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8
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Trieu NHK, Mai TA, Pham HM. Critical hematological parameters in bleeding during extracorporeal membrane oxygenation support. J Artif Organs 2024:10.1007/s10047-024-01466-8. [PMID: 39133377 DOI: 10.1007/s10047-024-01466-8] [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: 05/04/2024] [Accepted: 08/06/2024] [Indexed: 08/13/2024]
Abstract
Bleeding complications are frequently observed in patients undergoing extracorporeal membrane oxygenation and are associated with increased mortality. Due to the complex mechanisms, managing bleeding during ECMO remains a challenge. Acquired von Willebrand syndrome (AVWS) in ECMO highlights a potentially reduced affinity of von Willebrand factor (vWF) for binding to platelets and collagen in response to vascular damage, thus contributing to increased bleeding in ECMO patients. Conventional coagulation parameters are incomplete predictors for bleeding in ECMO patients, whereas AVWS is often overlooked due to the absence of vWF evaluation in the coagulation profile. Therefore, clinical physicians should evaluate AVWS in patients experiencing bleeding complications during ECMO support.
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Affiliation(s)
- Ngan Hoang Kim Trieu
- Department of Intensive Care Medicine, Cho Ray Hospital, Ho Chi Minh City, Vietnam.
| | - Tuan Anh Mai
- Detroit Medical Center, Wayne State University, Detroit, USA
| | - Huy Minh Pham
- Department of Intensive Care Medicine, Cho Ray Hospital, Ho Chi Minh City, Vietnam
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9
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Goldstein DJ, Kanwar M, Cowger J, Patel S, Meyer DM, Molina E, Salerno C, Elmer A, Schettle S, Teuteberg J, Pagani F, Stehlik J. Extrinsic Outflow Graft Obstruction of the HeartMate 3 LVAD: A State-of-the-Art Review. J Heart Lung Transplant 2024:S1053-2498(24)01739-X. [PMID: 39019352 DOI: 10.1016/j.healun.2024.07.005] [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: 04/24/2024] [Revised: 06/27/2024] [Accepted: 07/09/2024] [Indexed: 07/19/2024] Open
Abstract
While notable improvements in survival, incidence of hemocompatibility-related adverse events, hospitalizations and cost have been demonstrated with the only commercially available durable left ventricular assist device, a category of pump malfunctions characterized by outflow graft obstruction has been noted with broader use and clinical follow up of recipients of this technology. Of particular concern, is the accumulation of acellular biodebris between the outflow graft and bend relief covering the outflow graft at its origin with the pump (which we term extrinsic outflow graft obstruction at the bend relief, or EOGO-BR). This process tends to be insidious, occurs late in the postoperative course, can be challenging to diagnose, and can result in significant morbidity and mortality. Herein we provide a review of this complication and outline diagnostic, treatment and preventive strategies.
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Affiliation(s)
- Daniel J Goldstein
- Department of Cardiothoracic and Vascular Surgery, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY.
| | - Manreet Kanwar
- Cardiovascular Institute at Allegheny Health Network, Pittsburgh PA
| | - Jennifer Cowger
- Cardiovascular Medicine, Henry Ford Medical Center, Detroit, MI
| | - Snehal Patel
- Division of Cardiology, Montefiore Medical Center, Bronx, NY
| | - Dan M Meyer
- Department of Cardiovascular Surgery, Baylor Scott and White Health, Dallas, TX
| | - Ezequiel Molina
- Piedmont Heart Institute - Samsky Advanced Heart Failure Center, Atlanta, GA
| | - Christopher Salerno
- Department of Surgery, University of Chicago School of Medicine and Medical Center, Chicago, IL
| | - Ashley Elmer
- Division of Cardiac Surgery, University of Utah, Salt Lake City, UT
| | - Sarah Schettle
- Department of Cardiovascular Surgery, Mayo Clinic, Rochester, MN
| | - Jeffrey Teuteberg
- Division of Cardiovascular Medicine, Stanford University, Palo Alto, CA
| | - Francis Pagani
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI
| | - Josef Stehlik
- Division of Cardiovascular Medicine, University of Utah School of Medicine, Salt Lake City, UT
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10
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Ohlsson L, Sandstedt M, Papageorgiou JM, Svensson A, Bolger A, Tamás É, Granfeldt H, Ebbers T, Lantz J. Haemodynamic significance of extrinsic outflow graft stenoses during HeartMate 3™ therapy. EUROPEAN HEART JOURNAL. IMAGING METHODS AND PRACTICE 2024; 2:qyae082. [PMID: 39224624 PMCID: PMC11367968 DOI: 10.1093/ehjimp/qyae082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 08/05/2024] [Indexed: 09/04/2024]
Abstract
Aims The HeartMate 3 (HM3) implantable left ventricular assist device connects the left ventricle apex to the aorta via an outflow graft. Extrinsic obstruction of the graft (eOGO) is associated with serious morbidity and mortality and recently led to a Food and Drug Administration Class 1 device recall of HM3. This study aimed to provide a better understanding of the haemodynamic impact of extrinsic stenoses. Methods and results Computed tomography (CT) images of two retrospectively identified patients with eOGO (29 and 36% decrease in cross-sectional area, respectively, by radiological evaluation) were acquired with a novel photon-counting CT system. Numerical evaluations of haemodynamics were conducted using a high-fidelity 3D computational fluid dynamics approach on both the patient-specific graft geometries and in two virtually augmented stenotic severities and three device flows. Visual analysis identified increased velocity, pressure, and turbulent flow in the outer anterior curvature of the outflow graft; however, changes in graft pressure gradients were slight (1-9 mmHg) across the range of stenosis severities and flow rates tested. Conclusion Evidence of eOGO during HM3 support and the recent device recall can provoke clinical apprehension and interventions. The haemodynamic impact of a stenosis detected visually or by quantification of cross-sectional area reduction may be difficult to predict and easily overestimated. This numerical study suggests that, for clinically encountered flow rates and stenosis severities below 61% in cross-sectional area decrease, eOGO may have low haemodynamic impact. This suggests that patients without symptoms or signs consistent with haemodynamically significant obstruction might be managed expectantly.
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Affiliation(s)
- Linus Ohlsson
- Department of Cardiothoracic and Vascular Surgery, Linköping University, 581 83 Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
- Center of Medical Image Science and Visualization (CMIV), Linköping University, 581 83 Linköping, Sweden
| | - Mårten Sandstedt
- Center of Medical Image Science and Visualization (CMIV), Linköping University, 581 83 Linköping, Sweden
- Department of Radiology in Linköping, Linköping University, Linköping, Sweden
| | | | - Anders Svensson
- Department of Cardiothoracic and Vascular Surgery, Linköping University, 581 83 Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
| | - Ann Bolger
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Éva Tamás
- Department of Cardiothoracic and Vascular Surgery, Linköping University, 581 83 Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
- Center of Medical Image Science and Visualization (CMIV), Linköping University, 581 83 Linköping, Sweden
| | - Hans Granfeldt
- Department of Cardiothoracic and Vascular Surgery, Linköping University, 581 83 Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
| | - Tino Ebbers
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
- Center of Medical Image Science and Visualization (CMIV), Linköping University, 581 83 Linköping, Sweden
| | - Jonas Lantz
- Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
- Center of Medical Image Science and Visualization (CMIV), Linköping University, 581 83 Linköping, Sweden
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11
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Straccia A, Chassagne F, Barbour MC, Beckman J, Li S, Mahr C, Aliseda A. A Computational Investigation of the Effects of Temporal Synchronization of Left Ventricular Assist Device Speed Modulation with the Cardiac Cycle on Intraventricular Hemodynamics. Ann Biomed Eng 2024; 52:1763-1778. [PMID: 38517620 DOI: 10.1007/s10439-024-03489-x] [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: 10/20/2023] [Accepted: 03/07/2024] [Indexed: 03/24/2024]
Abstract
Patients with advanced heart failure are implanted with a left ventricular assist device (LVAD) as a bridge-to-transplantation or destination therapy. Despite advances in pump design, the risk of stroke remains high. LVAD implantation significantly alters intraventricular hemodynamics, where regions of stagnation or elevated shear stresses promote thrombus formation. Third generation pumps incorporate a pulsatility mode that modulates rotational speed of the pump to enhance in-pump washout. We investigated how the timing of the pulsatility mode with the cardiac cycle affects intraventricular hemodynamic factors linked to thrombus formation. Computational fluid dynamics simulations with Lagrangian particle tracking to model platelet behavior in a patient-specific left ventricle captured altered intraventricular hemodynamics due to LVAD implantation. HeartMate 3 incorporates a pulsatility mode that modulates the speed of the pump every two seconds. Four different timings of this pulsatility mode with respect to the cardiac cycle were investigated. A strong jet formed between the mitral valve and inflow cannula. Blood stagnated in the left ventricular outflow tract beneath a closed aortic valve, in the near-wall regions off-axis of the jet, and in a large counterrotating vortex near the anterior wall. Computational results showed good agreement with particle image velocimetry results. Synchronization of the pulsatility mode with peak systole decreased stasis, reflected in the intraventricular washout of virtual contrast and Lagrangian particles over time. Temporal synchronization of HeartMate 3 pulsatility with the cardiac cycle reduces intraventricular stasis and could be beneficial for decreasing thrombogenicity.
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Affiliation(s)
- Angela Straccia
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA.
| | | | - Michael C Barbour
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - Jennifer Beckman
- Division of Cardiology, University of Washington, Seattle, WA, USA
| | - Song Li
- Institute for Advanced Cardiac Care, Medical City Healthcare, Dallas, TX, USA
| | - Claudius Mahr
- Institute for Advanced Cardiac Care, Medical City Healthcare, Dallas, TX, USA
| | - Alberto Aliseda
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
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12
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Dimond M, Looby M, Shah B, Sinha SS, Isseh I, Rollins AT, Abdul-Aziz AA, Kennedy J, Tang DG, Klein KM, Casselman S, Vermeulen C, Sheaffer W, Snipes M, O'connor CM, Shah P. Design and Rationale for the Direct Oral Anticoagulant Apixaban in Left Ventricular Assist Devices (DOAC LVAD) Study. J Card Fail 2024; 30:819-828. [PMID: 37956897 DOI: 10.1016/j.cardfail.2023.10.473] [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: 08/02/2023] [Revised: 09/28/2023] [Accepted: 10/17/2023] [Indexed: 11/21/2023]
Abstract
Implantable left ventricular assist device (LVAD) therapy is used to improve quality of life, alleviate symptoms and extend survival rates in patients with advanced heart failure. Patients with LVADs require chronic anticoagulation to reduce the risk of thromboembolic complications, and they commonly experience bleeding events. Apixaban is a direct oral anticoagulant that has become first-line therapy for patients with nonvalvular atrial fibrillation and venous thromboembolism; however, its safety in patients with LVADs has not been well characterized. The evaluation of the hemocompatibility in the DOAC LVAD (Direct Oral Anti-Coagulant apixaban in Left Ventricular Assist Devices) trial is a phase 2, open-label trial of patients with LVADs who were randomized to either apixaban or warfarin therapy. Patients randomized to apixaban will be started on a dosage of 5 mg twice daily, whereas those randomized to warfarin will be managed at an International Normalized Ratio goal of 2.0-2.5. All patients will be treated with aspirin at 81 mg daily. We plan to randomize and follow as many as 40 patients for 24 weeks to evaluate the primary outcomes of freedom from death or hemocompatibility-related adverse events (stroke, device thrombosis, bleeding, aortic root thrombus, and arterial non-CNS thromboembolism). The DOAC LVAD trial will establish the feasibility of apixaban anticoagulant therapy in patients with LVADs. Clinicaltrials.gov: NCT04865978.
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Affiliation(s)
- Matthew Dimond
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Mary Looby
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Bhruga Shah
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Shashank S Sinha
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Iyad Isseh
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Allman T Rollins
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Ahmad A Abdul-Aziz
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Jamie Kennedy
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Daniel G Tang
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Katherine M Klein
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Samantha Casselman
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Christen Vermeulen
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Wendy Sheaffer
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | - Meredith Snipes
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA
| | | | - Palak Shah
- From the Advanced Heart Failure, Inova Schar Heart and Vascular, Falls Church, VA.
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13
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Escher A, Miric S, Thamsen B, Giuffrida R, Schmidt P, Weinhold B, Hübler M, Zimpfer D, Kolar JW, Granegger M. Multiobjective Optimization of Rotodynamic Blood Pumps: The Use Case of a Cavopulmonary Assist Device. ASAIO J 2024:00002480-990000000-00497. [PMID: 38829985 DOI: 10.1097/mat.0000000000002237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024] Open
Abstract
Comprehensive optimization of rotodynamic blood pumps (RBPs) requires the consideration of three partially conflicting objectives: size, hemocompatibility, and motor efficiency. Optimizing these individual objectives independently, the potential of multiobjective optimizations often remains untapped. This study aimed at the multiobjective optimization of an RBP for cavopulmonary support accounting for all three objectives simultaneously. Hydraulic and electromagnetic design spaces were characterized using computational fluid dynamics and computational electromagnetics, respectively. Design variables included secondary flow gap widths, impeller diameters, and stator heights. The size objective encompassed the RBP widths and heights, the hemocompatibility objective was a weighted composite measure of well-established metrics, and the motor objective was determined by motor losses. Multiobjective optimization was performed through Pareto analysis. 81 designs were considered, and 21 Pareto-optimal designs were identified. The Pareto analysis indicated that hemocompatibility performance could be improved by 72.4% with a concomitant 1.5% reduction in the baseline pump volume. This, however, entailed an increase in motor losses by 0.2 W, while still meeting design requirements, with maximum local temperature rises remaining below 0.4 K. The multiobjective optimization led to a Pareto front, demonstrating the feasibility to improve hemocompatibility at reduced pump volume, however, at the cost of a diminished yet still acceptable motor performance.
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Affiliation(s)
- Andreas Escher
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Spasoje Miric
- Department of Mechatronics, University of Innsbruck, Innsbruck, Austria
| | - Bente Thamsen
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Rosario Giuffrida
- Power Electronic Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland
| | - Pascal Schmidt
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Benjamin Weinhold
- Power Electronic Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland
| | - Michael Hübler
- Children's Heart Clinic, University Heart & Vascular Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Daniel Zimpfer
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
- Division of Cardiac Surgery, Department of Surgery, Medical University Graz, Graz, Austria
| | - Johann Walter Kolar
- Power Electronic Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland
| | - Marcus Granegger
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
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14
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Yin MY, Maneta E, Kyriakopoulos CP, Michaels AT, Genovese LD, Indaram MB, Wever-Pinzon O, Singh R, Tseliou E, Taleb I, Nemeh HW, Alharethi R, Tang DG, Goldstein J, Hanff TC, Selzman CH, Cowger J, Kanwar M, Shah P, Drakos SG. Cardiac Reverse Remodeling Mediated by HeartMate 3 Left Ventricular Assist Device: Comparison to Older Generation Devices. ASAIO J 2024:00002480-990000000-00495. [PMID: 38810218 DOI: 10.1097/mat.0000000000002245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024] Open
Abstract
Currently, the fully magnetically levitated left ventricular assist device (LVAD) HeartMate 3 (HM3) is the only commercially available device for advanced heart failure (HF) patients. However, the left ventricular (LV) functional and structural changes following mechanical unloading and circulatory support (MCS) with the HM3 have not been investigated. We compared the reverse remodeling induced by the HM3 to older generation continuous-flow LVADs. Chronic HF patients (n = 405) undergoing MCS with HeartWare Ventricular Assist Device (HVAD, n = 115), HM3 (n = 186), and HeartMate II (HM2, n = 104) at four programs were included. Echocardiograms were obtained preimplant and at 1, 3, 6, and 12 months following LVAD implantation. There were no differences in the postimplant serial LV ejection fraction (LVEF) between the devices. The postimplant LV internal diastolic diameter (LVIDd) was significantly lower for HM2 at 3 and 6 months compared with HVAD and HM3. The proportion of patients achieving "cardiac reverse remodeling responder" status (defined as LVEF improvement to ≥40% and LVIDD ≤5.9 cm) was 11.9%, and was similar between devices. HeartMate 3 appears to result in similar cardiac reverse remodeling as older generation CF-LVADs, suggesting that the fully magnetically levitated device technology could provide an effective platform to further study and promote cardiac reverse remodeling.
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Affiliation(s)
- Michael Yaoyao Yin
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Eleni Maneta
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Christos P Kyriakopoulos
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Alexander T Michaels
- Division of Cardiology and Cardiothoracic Surgery, Henry Ford Hospital, Detroit, Michigan
| | - Leonard D Genovese
- Division of Cardiology and Cardiothoracic Surgery, Inova Heart and Vascular Institute, Falls Church, Virginia
| | - Mahathi B Indaram
- Division of Cardiology and Cardiothoracic Surgery, Allegheny Health Network, Pittsburgh, Pennsylvania
| | - Omar Wever-Pinzon
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Ramesh Singh
- Division of Cardiology and Cardiothoracic Surgery, Inova Heart and Vascular Institute, Falls Church, Virginia
| | - Eleni Tseliou
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Iosif Taleb
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Hassan W Nemeh
- Division of Cardiology and Cardiothoracic Surgery, Henry Ford Hospital, Detroit, Michigan
| | - Rami Alharethi
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Daniel G Tang
- Division of Cardiology and Cardiothoracic Surgery, Inova Heart and Vascular Institute, Falls Church, Virginia
| | - Jake Goldstein
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Thomas C Hanff
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Craig H Selzman
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
| | - Jennifer Cowger
- Division of Cardiology and Cardiothoracic Surgery, Henry Ford Hospital, Detroit, Michigan
| | - Manreet Kanwar
- Division of Cardiology and Cardiothoracic Surgery, Allegheny Health Network, Pittsburgh, Pennsylvania
| | - Palak Shah
- Division of Cardiology and Cardiothoracic Surgery, Inova Heart and Vascular Institute, Falls Church, Virginia
| | - Stavros G Drakos
- From the Utah Cardiac Recovery (UCAR) Program (Divisions of Cardiology and Cardiothoracic Surgery at University of Utah Health & School of Medicine, Intermountain Medical Center, and George E. Wahlen Department of Veterans Affairs Medical Center), Salt Lake City, Utah
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15
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Tscharre M, Mutschlechner D, Schlöglhofer T, Wiedemann D, Zimpfer D, Gremmel T. Omission of Antiplatelet Therapy in Patients With HeartMate 3 Left Ventricular Assist Devices: A Systematic Review and Meta-Analysis. ASAIO J 2024:00002480-990000000-00479. [PMID: 38728742 DOI: 10.1097/mat.0000000000002225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024] Open
Abstract
The HeartMate 3 (HM3) left ventricular assist device has decreased thromboembolic events and minimized the risk of pump thrombosis. However, bleeding complications due to combined antithrombotic therapy with a vitamin K antagonist (VKA) and aspirin remain high. Only limited data on the safety of VKA monotherapy in HM3 patients are available. A systematic search on the main databases was performed. Observational data and randomized trials were eligible for this analysis. As primary endpoint, we analyzed hemocompatibility-related adverse events (HRAE). As secondary endpoints, we investigated the individual components of the primary endpoint. The analysis was carried out using the odds ratio (OR) as outcome measure. A random-effects model was fitted to the data. Five manuscripts fulfilled the inclusion criteria. These trials included 785 patients (381 on VKA monotherapy, 404 on VKA and aspirin). VKA monotherapy significantly reduced HRAE (OR: 0.11 [95% confidence interval {CI}: 0.02-0.59], p = 0.01, I2 = 87%). The reduction was driven by a decrease in bleeding complications (OR: 0.12 [95% CI: 0.02-0.62], p = 0.01, I2 = 86%) without increasing the rates of thromboembolic events (OR: 0.69 [95% CI: 0.26-1.81], p = 0.45, I = 0%). Vitamin K antagonist monotherapy is associated with a significant reduction of bleeding events without increasing the risk of thromboembolic complications in HM3 patients.
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Affiliation(s)
- Maximilian Tscharre
- From the Department of Internal Medicine, Cardiology and Nephrology, Landesklinikum Wiener Neustadt, Wiener Neustadt, Austria
- Institute of Vascular Medicine and Cardiac Electrophysiology, Karl Landsteiner Society, St. Pölten, Austria
| | - David Mutschlechner
- Department of Internal Medicine I, Cardiology and Intensive Care Medicine, Landesklinikum Mistelbach-Gänserndorf, Mistelbach, Austria
| | - Thomas Schlöglhofer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Dominik Wiedemann
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Daniel Zimpfer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Thomas Gremmel
- Department of Internal Medicine I, Cardiology and Intensive Care Medicine, Landesklinikum Mistelbach-Gänserndorf, Mistelbach, Austria
- Institute of Cardiovascular Pharmacotherapy and Interventional Cardiology, Karl Landsteiner Society, St. Pölten, Austria
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16
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Lopez-Santana G, De Rosis A, Grant S, Venkateswaran R, Keshmiri A. Enhancing the implantation of mechanical circulatory support devices using computational simulations. Front Bioeng Biotechnol 2024; 12:1279268. [PMID: 38737533 PMCID: PMC11084291 DOI: 10.3389/fbioe.2024.1279268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 04/08/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction: Patients with end-stage heart failure (HF) may need mechanical circulatory support such as a left ventricular assist device (LVAD). However, there are a range of complications associated with LVAD including aortic regurgitation (AR) and thrombus formation. This study assesses whether the risk of developing aortic conditions can be minimised by optimising LVAD implantation technique. Methods: In this work, we evaluate the aortic flow patterns produced under different geometrical parameters for the anastomosis of the outflow graft (OG) to the aorta using computational fluid dynamics (CFD). A three-dimensional aortic model is created and the HeartMate III OG positioning is simulated by modifying (i) the distance from the anatomic ventriculo-arterial junction (AVJ) to the OG, (ii) the cardinal position around the aorta, and (iii) the angle between the aorta and the OG. The continuous LVAD flow and the remnant native cardiac cycle are used as inlet boundaries and the three-element Windkessel model is applied at the pressure outlets. Results: The analysis quantifies the impact of OG positioning on different haemodynamic parameters, including velocity, wall shear stress (WSS), pressure, vorticity and turbulent kinetic energy (TKE). We find that WSS on the aortic root (AoR) is around two times lower when the OG is attached to the coronal side of the aorta using an angle of 45° ± 10° at a distance of 55 mm. Discussion: The results show that the OG placement may significantly influence the haemodynamic patterns, demonstrating the potential application of CFD for optimising OG positioning to minimise the risk of cardiovascular complications after LVAD implantation.
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Affiliation(s)
- Gabriela Lopez-Santana
- School of Engineering, The University of Manchester, Manchester, United Kingdom
- Department of Cardiothoracic Transplantation and Mechanical Circulatory Support, Wythenshawe Hospital, Manchester, United Kingdom
| | - Alessandro De Rosis
- School of Engineering, The University of Manchester, Manchester, United Kingdom
| | - Stuart Grant
- Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
| | - Rajamiyer Venkateswaran
- Department of Cardiothoracic Transplantation and Mechanical Circulatory Support, Wythenshawe Hospital, Manchester, United Kingdom
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
| | - Amir Keshmiri
- School of Engineering, The University of Manchester, Manchester, United Kingdom
- Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
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17
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Min JJ, Cho YH, Lee SM, Lee JH. Anesthetic management for non-cardiac surgery in patients with left ventricular assist devices. Korean J Anesthesiol 2024; 77:175-184. [PMID: 36912004 PMCID: PMC10982535 DOI: 10.4097/kja.23169] [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: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023] Open
Abstract
With the growing number of patients undergoing left ventricular assist device (LVAD) implantation and improved survival in this population, more patients with LVADs are presenting for various types of non-cardiac surgery. Therefore, anesthesiologists need to understand the physiology and adequately prepare for the perioperative management of this unique patient population. This review addresses perioperative considerations and intraoperative management for the safe and successful management of patients with an LVAD undergoing non-cardiac surgery. Understanding the basic physiology of preload dependency and afterload sensitivity in these patients is essential. The main considerations include a collaborative preoperative multidisciplinary approach, perioperative care aimed at optimizing the intravascular volume and right ventricular function, and maintaining the afterload within recommended ranges for optimal LVAD function.
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Affiliation(s)
- Jeong-Jin Min
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yang Hyun Cho
- Department of Thoracic & Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sangmin M. Lee
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jong-Hwan Lee
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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18
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Tsiouris A, Slaughter MS, Jeyakumar AKC, Protos AN. Left ventricular assist devices: yesterday, today, and tomorrow. J Artif Organs 2024:10.1007/s10047-024-01436-0. [PMID: 38451441 DOI: 10.1007/s10047-024-01436-0] [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: 10/11/2023] [Accepted: 01/21/2024] [Indexed: 03/08/2024]
Abstract
The shortcomings of expense, power requirements, infection, durability, size, and blood trauma of current durable LVADs have been recognized for many years. The LVADs of tomorrow aspire to be fully implantable, durable, mitigate infectious risk, mimic the pulsatile nature of the native cardiac cycle, as well as minimize bleeding and thrombosis. Power draw, battery cycle lifespan and trans-cutaneous energy transmission remain barriers to completely implantable systems. Potential solutions include decreases in pump electrical draw, improving battery lifecycle technology and better trans-cutaneous energy transmission, potentially from Free-range Resonant Electrical Energy Delivery. In this review, we briefly discuss the history of LVADs and summarize the LVAD devices in the development pipeline seeking to address these issues.
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Affiliation(s)
- Athanasios Tsiouris
- Department of Surgery, Division of Cardiac Surgery, University of Mississippi Medical Center, 2500 N State St, Jackson, MS, 39216, USA.
| | - Mark S Slaughter
- Department of Cardiovascular and Thoracic Surgery, University of Louisville, 201 Abraham Flexner Way, Louisville, KY, 40202, USA
| | - Ashok Kumar Coimbatore Jeyakumar
- Department of Surgery, Division of Cardiac Surgery, University of Mississippi Medical Center, 2500 N State St, Jackson, MS, 39216, USA
| | - Adam N Protos
- Department of Surgery, Division of Cardiac Surgery, University of Mississippi Medical Center, 2500 N State St, Jackson, MS, 39216, USA
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19
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Nascimbene A, Bark D, Smadja DM. Hemocompatibility and biophysical interface of left ventricular assist devices and total artificial hearts. Blood 2024; 143:661-672. [PMID: 37890145 PMCID: PMC10900168 DOI: 10.1182/blood.2022018096] [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] [Received: 01/30/2023] [Revised: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 10/29/2023] Open
Abstract
ABSTRACT Over the past 2 decades, there has been a significant increase in the utilization of long-term mechanical circulatory support (MCS) for the treatment of cardiac failure. Left ventricular assist devices (LVADs) and total artificial hearts (TAHs) have been developed in parallel to serve as bridge-to-transplant and destination therapy solutions. Despite the distinct hemodynamic characteristics introduced by LVADs and TAHs, a comparative evaluation of these devices regarding potential complications in supported patients, has not been undertaken. Such a study could provide valuable insights into the complications associated with these devices. Although MCS has shown substantial clinical benefits, significant complications related to hemocompatibility persist, including thrombosis, recurrent bleeding, and cerebrovascular accidents. This review focuses on the current understanding of hemostasis, specifically thrombotic and bleeding complications, and explores the influence of different shear stress regimens in long-term MCS. Furthermore, the role of endothelial cells in protecting against hemocompatibility-related complications of MCS is discussed. We also compared the diverse mechanisms contributing to the occurrence of hemocompatibility-related complications in currently used LVADs and TAHs. By applying the existing knowledge, we present, for the first time, a comprehensive comparison between long-term MCS options.
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Affiliation(s)
- Angelo Nascimbene
- Advanced Cardiopulmonary Therapies and Transplantation, University of Texas, Houston, TX
| | - David Bark
- Division of Hematology and Oncology, Department of Pediatrics, Washington University in St. Louis, St. Louis, MO
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO
| | - David M. Smadja
- Université de Paris-Cité, Innovative Therapies in Haemostasis, INSERM, Paris, France
- Hematology Department, Assistance Publique–Hôpitaux de Paris, Georges Pompidou European Hospital, Paris, France
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20
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Grinstein J, Ziegler LA, Shah P. Next generation device interrogation for the HeartMate 3. J Heart Lung Transplant 2024; 43:261-262. [PMID: 38012977 DOI: 10.1016/j.healun.2023.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 11/11/2023] [Indexed: 11/29/2023] Open
Affiliation(s)
- Jonathan Grinstein
- Section on Cardiology, Department of Medicine, University of Chicago Medical Center, Chicago, Illinois
| | - Luke A Ziegler
- Procirca Mechanical Circulatory Support, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Palak Shah
- Heart Failure, Mechanical Circulatory Support, & Transplant, Inova Schar Heart and Vascular, Falls Church, Virginia.
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21
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Schlöglhofer T, Gross C, Abart T, Schaefer AK, Marko C, Röhrich M, Widhalm G, Kaufmann F, Weigel I, Al Asadi H, Karner B, Riebandt J, Wiedemann D, Laufer G, Schima H, Zimpfer D. HeartMate 3 Snoopy: Noninvasive cardiovascular diagnosis of patients with fully magnetically levitated blood pumps during echocardiographic speed ramp tests and Valsalva maneuvers. J Heart Lung Transplant 2024; 43:251-260. [PMID: 37769887 DOI: 10.1016/j.healun.2023.09.011] [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: 03/07/2023] [Revised: 08/30/2023] [Accepted: 09/18/2023] [Indexed: 10/03/2023] Open
Abstract
PURPOSE The HeartMate 3 (HM3) left ventricular assist device (LVAD) has demonstrated excellent clinical outcomes; however, pump speed optimization is challenging with the available HM3 monitoring. Therefore, this study reports on clinical HM3 parameters collected with a noninvasive HM3 monitoring system (HM3 Snoopy) during echocardiographic speed ramp tests and Valsalva maneuvers. METHODS In this prospective, single-center study, the HM3 data communication between the controller and pump was recorded with a novel data acquisition system. Twelve pump parameters sampled every second (1 Hz) and clinical assessments (echocardiography, electrocardiogram (ECG), and blood pressure measurement) during speed ramp tests were analyzed using Pearson's correlation (r, median [IQR]). The cause for the occurrence of pulsatility index (PI)-events during ramp speed tests and valsalva maneuvers was investigated. RESULTS In 24 patients (age: 58.9 ± 8.8 years, body mass index: 28.1 ± 5.1 kg/m2, female: 20.8%), 35 speed ramp tests were performed with speed changes in the range of ±1000 rpm from a baseline speed of 5443 ± 244 rpm. Eight HM3 pump parameters from estimated flow, motor current, and LVAD speed together with blood pressure showed positive collinearities (r = 0.9 [0.1]). Negative collinearities were observed for pump flow pulsatility, pulsatility index, rotor noise, and left ventricular diameters (r = -0.8 [0.1]), whereas rotor displacement and heartrate showed absence of collinearities (r = -0.1 [0.08]). CONCLUSIONS In this study, the HM3 Snoopy was successfully used to acquire more parameters from the HM3 at a higher sampling rate. Analysis of HM3 per-second data provide additional clinical diagnostic information on heart-pump interactions and cause of PI-events.
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Affiliation(s)
- Thomas Schlöglhofer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
| | - Christoph Gross
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Theodor Abart
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | | | - Christiane Marko
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Michael Röhrich
- Department of Anesthesia, Intensive Care Medicine and Pain Medicine, Medical University of Vienna, Vienna, Austria
| | - Gregor Widhalm
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Friedrich Kaufmann
- Deutsches Herzzentrum der Charité (DHZC), Department of Cardiothoracic and Vascular Surgery, Berlin, Germany
| | - Ingo Weigel
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Hebe Al Asadi
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Barbara Karner
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Julia Riebandt
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Dominik Wiedemann
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Günther Laufer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Heinrich Schima
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Daniel Zimpfer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
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22
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Yaranov DM, Baldridge AS, Gonzalez M, Biglane JB, Tanaka D, Fischer W, Larkin C, Ullah R, Chaudhry SP, Pham DT. Anticoagulation Bridging in Patients With Left Ventricular Assist Device: A Regional Analysis of HeartMate 3 Recipients. ASAIO J 2024; 70:93-98. [PMID: 37862687 DOI: 10.1097/mat.0000000000002067] [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: 10/22/2023] Open
Abstract
Advances in left ventricular assist device technologies have led to an improvement in pump hemocompatibility and outcomes. Because of concerns of thromboembolic complications in prior generations of left ventricular assist devices, bridging with parenteral anticoagulants was routinely. Management strategies of subtherapeutic INRs and their effects on the current generation of devices deserve review. We performed analysis of the MOMENTUM 3 trial including 6 centers in the mid-America region. Patients with subtherapeutic INRs (INR < 2) occurring after the index admission underwent chart review to determine the management strategies taken by clinicians. Strategies were divided into two groups, bridging or nonbridging. Of the 225 patients included in the analysis, 130 (58%) patients had a total of 235 subtherapeutic international normalized ratio (INR) events. Most (n = 179, 76.2%) of these INRs were not bridged (n = 100 warfarin dose adjustment, n = 79 no change in warfarin dose). Among those INRs (n = 56, 23.8%) treated with bridging, approximately half (n = 30, 53.6%) were treated with subcutaneous agents and other half (n = 26, 46.4%) were treated with intravenous agents. There was no difference in individual outcomes or composite endpoints of death, rehospitalization, CVA, or bleeding events between the groups.
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Affiliation(s)
| | | | | | | | | | | | - Chris Larkin
- Ascension Saint Thomas West, Nashville, Tennessee
| | - Rafath Ullah
- Aurora St. Luke's Medical Center, Milwaukee, Wisconsin
| | | | - Duc Thinh Pham
- Northwestern University Feinberg School of Medicine, Chicago, Illinois
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23
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Kant K, Trumper DL. Extracorporeal Blood Pump driven by a Novel Bearingless Split-Tooth Flux-Reversal Motor. IEEE/ASME TRANSACTIONS ON MECHATRONICS : A JOINT PUBLICATION OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY AND THE ASME DYNAMIC SYSTEMS AND CONTROL DIVISION 2024; 29:271-278. [PMID: 39310854 PMCID: PMC11415251 DOI: 10.1109/tmech.2023.3275568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
This paper describes a novel bearingless split tooth flux reversal motor with integrated centrifugal blood pump. This motor has a magnet-free rotor, and is capable of operating at up to 3000 rpm with up to 100 mNm torque. The motor also has 50 N radial force capability for centering the rotor. The motor rotor is 50 mm diameter, housed in a 170mm wide stator. The motor has a novel magnetic configuration wherein the force generation is independent of the rotor angle. This allows simple radial force generation using stator-fixed currents. The motor torque is generated using commutated two-phase currents. Finite element simulations are used to optimize the design in order to achieve sufficient radial force and motor torque, while minimizing cogging torque. The design also achieves an axial passive magnetic stiffness of 5.4 N/mm, which is the constraint on axial motions of the rotor. This paper includes mechanical design and fabrication details, as well as experimental closed loop levitation and speed control performance. With an integrated impeller, the rotor and the centrifugal pump are tested by pumping fluid in a closed circuit to obtain experimental pressure-flow curves with impeller-limited performance.
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Affiliation(s)
- Krishan Kant
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 USA
| | - David L Trumper
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
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24
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Georges G, Trudeau F, Potvin J, Potus F, Martineau S, Généreux P. Preservation of von Willebrand Factor Activity With the ModulHeart Device. JACC Basic Transl Sci 2024; 9:33-42. [PMID: 38362340 PMCID: PMC10864901 DOI: 10.1016/j.jacbts.2023.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 02/17/2024]
Abstract
von Willebrand Factor (VWF) destruction is common with current heart pumps. This study evaluates VWF activity with ModulHeart, a novel device using 3 micropumps in parallel. In model 1, ModulHeart was compared with Impella devices in vitro. In model 2, 3 healthy swine received ModulHeart. Model 3 includes VWF data from patients who underwent protected percutaneous coronary intervention with ModulHeart. In models 1, 2, and 3, ModulHeart resulted in preservation of VWF, whereas there was a 27% and 19% reduction in VWF activity with the Impella CP and 5.0, respectively. ModulHeart features a unique design and demonstrated preservation of VWF activity.
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Affiliation(s)
| | | | - Jeannot Potvin
- Centre Hospitalier de l’Université de Montréal, Montreal, Quebec, Canada
| | | | | | - Philippe Généreux
- Gagnon Cardiovascular Institute, Morristown Medical Center, Morristown, New Jersey, USA
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25
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Inchaustegui CA, Patel A, Lamba HK, Brown A, Arunthamakun J, Ting K, Chatterjee S, Nair AP, George JK, Shafii AE, Liao KK, Civitello AB. Impact of time off anticoagulation in patients with continuous-flow left ventricular assist devices. J Artif Organs 2023; 26:275-286. [PMID: 36208373 DOI: 10.1007/s10047-022-01367-8] [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: 04/22/2022] [Accepted: 09/20/2022] [Indexed: 10/10/2022]
Abstract
Patients with left ventricular assist devices (LVADs) receive anticoagulation to decrease the risk of thrombosis. Various circumstances require discontinuing anticoagulation in LVAD patients, but the risks entailed are not well defined. In a retrospective review of LVAD implantation procedures, we examined the effect of time off anticoagulation on thrombosis and mortality rates after implantation. An international normalized ratio ≤ 1.5 was used to screen for patients taken off anticoagulation. Patients were divided into three groups by the cumulative number of days off anticoagulation: no discontinuation, short-term discontinuation (< 30 days), and long-term discontinuation (≥ 30 days). Rates of ischemic stroke, pump thrombosis, and mortality were compared among groups. Of 245 patients who underwent LVAD implantation during the study, 70 (28.6%) were off anticoagulation during follow-up: 37 (15.1%) had short-term discontinuation (median, 11 days), and 33 (13.5%) had long-term discontinuation (median, 124 days). Patients with long-term discontinuation had a higher rate of ischemic stroke (adjusted hazard ratio 8.5, p = 0.001) and death (adjusted hazard ratio 3.9, p = 0.001). The three groups did not differ in pump thrombosis rate. We conclude that after LVAD implantation, discontinuing anticoagulation for ≥ 30 days is independently associated with an increased risk of ischemic stroke and death.
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Affiliation(s)
- Christian A Inchaustegui
- Department of Medicine, Baylor College of Medicine, McNair Campus (MCHA) A10.193 MS: BCM903, 7200 Cambridge Street, Houston, TX, 77040, USA.
- Department of Cardiopulmonary Transplantation and the Center for Cardiac Support, Texas Heart Institute, 6770 Bertner Avenue, Houston, TX, 77030, USA.
| | - Ashley Patel
- Department of Medicine, Baylor College of Medicine, McNair Campus (MCHA) A10.193 MS: BCM903, 7200 Cambridge Street, Houston, TX, 77040, USA
| | - Harveen K Lamba
- Division of Cardiothoracic Transplantation and Circulatory Support, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA.
| | - Andrew Brown
- Department of Medicine, Baylor College of Medicine, McNair Campus (MCHA) A10.193 MS: BCM903, 7200 Cambridge Street, Houston, TX, 77040, USA
| | - Justin Arunthamakun
- Department of Medicine, Baylor College of Medicine, McNair Campus (MCHA) A10.193 MS: BCM903, 7200 Cambridge Street, Houston, TX, 77040, USA
| | - Kevin Ting
- Department of Medicine, Baylor College of Medicine, McNair Campus (MCHA) A10.193 MS: BCM903, 7200 Cambridge Street, Houston, TX, 77040, USA
| | - Subhasis Chatterjee
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
- Division of General Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
- Texas Heart Institute, Houston, TX, USA
| | - Ajith P Nair
- Division of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Joggy K George
- Texas Heart Institute, Houston, TX, USA
- Division of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Alexis E Shafii
- Division of Cardiothoracic Transplantation and Circulatory Support, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Kenneth K Liao
- Division of Cardiothoracic Transplantation and Circulatory Support, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Andrew B Civitello
- Division of Cardiothoracic Transplantation and Circulatory Support, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA
- Texas Heart Institute, Houston, TX, USA
- Division of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
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26
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Escher A, Thamsen B, Strauch C, Kertzscher U, Zimpfer D, Thamsen PU, Granegger M. In-Vitro Flow Validation of Third-Generation Ventricular Assist Devices: Feasibility and Challenges. ASAIO J 2023; 69:932-941. [PMID: 37418316 DOI: 10.1097/mat.0000000000002009] [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: 07/09/2023] Open
Abstract
Computational fluid dynamics (CFD) is a powerful tool for the in-silico evaluation of rotodynamic blood pumps (RBPs). Corresponding validation, however, is typically restricted to easily accessible, global flow quantities. This study showcased the HeartMate 3 (HM3) to identify feasibility and challenges of enhanced in-vitro validation in third-generation RBPs. To enable high-precision acquisition of impeller torques and grant access for optical flow measurements, the HM3 testbench geometry was geometrically modified. These modifications were reproduced in silico , and global flow computations validated along 15 operating conditions. The globally validated flow in the testbench geometry was compared with CFD-simulated flows in the original geometry to assess the impact of the necessary modifications on global and local hydraulic properties. Global hydraulic properties in the testbench geometry were successfully validated (pressure head: r = 0.999, root mean square error [RMSE] = 2.92 mmHg; torque: r = 0.996, RMSE = 0.134 mNm). In-silico comparison with the original geometry demonstrated good agreement ( r > 0.999, relative errors < 11.97%) of global hydraulic properties. Local hydraulic properties (errors up to 81.78%) and hemocopatibility predictions (deviations up to 21.03%), however, were substantially affected by the geometric modifications. Transferability of local flow measures derived on advanced in-vitro testbenches toward original pump designs is challenged by significant local effects associated with the necessary geometrical modifications.
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Affiliation(s)
- Andreas Escher
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Bente Thamsen
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Carsten Strauch
- Department of Fluid System Dynamics, Technische Universität Berlin, Berlin, Germany
| | - Ulrich Kertzscher
- Deutsches Herzzentrum der Charité - Medical Heart Center of Charité and German Heart Institute Berlin, Institute of Computer-assisted Cardiovascular Medicine, Biofluid Mechanics Laboratory, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Daniel Zimpfer
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
- Division of Cardiac Surgery, Department of Surgery, Medical University Graz, Graz, Austria
| | - Paul Uwe Thamsen
- Department of Fluid System Dynamics, Technische Universität Berlin, Berlin, Germany
| | - Marcus Granegger
- From the Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
- Deutsches Herzzentrum der Charité - Medical Heart Center of Charité and German Heart Institute Berlin, Institute of Computer-assisted Cardiovascular Medicine, Biofluid Mechanics Laboratory, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
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27
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Consolo F, Pieri M, Pazzanese V, Scandroglio AM, Pappalardo F. Longitudinal analysis of pump parameters over long-term support with the HeartMate 3 left ventricular assist device. J Cardiovasc Med (Hagerstown) 2023; 24:771-775. [PMID: 37409664 DOI: 10.2459/jcm.0000000000001522] [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: 07/07/2023]
Abstract
AIMS Recurrence of heart failure emerged as the main cause of long-term mortality in patients implanted with the HeartMate 3 (HM3) left ventricular assist device (LVAD). We aimed at deriving a possible mechanistic rationale of clinical outcomes and analyzed longitudinal changes in pump parameters over prolonged HM3 support to investigate long-term effects of pump settings on left ventricular mechanics. METHODS Data on pump parameters (i.e. pump speed, estimated flow, and pulsatility index) were prospectively recorded in consecutive HM3 patients following postoperative rehabilitation (baseline) and then at 6, 12, 24, 36, 48, and 60 months of support. RESULTS Data of 43 consecutive patients were analyzed. Pump parameters were set according to regular patients' follow-up, including clinical and echocardiographic assessment. We recorded a significant progressive increase in pump speed over the course of support: from 5200 (5050-5300) rpm at baseline to 5400 (5300-5600) rpm at 60 months of support ( P = 0.0007). Consistently with the increase in pump speed, a significant increase in pump flow ( P = 0.007) and a decrease in pulsatility index ( P = 0.005) were also recorded. CONCLUSION Our results reveal unique features of the HM3 on left ventricular activity. The need for progressive increase in pump support suggests indeed a lack of recovery and worsening of left ventricular function, which emerge as a possible mechanistic rationale of heart failure related mortality in HM3 patients. New algorithms to optimize pump settings should be envisioned to further improve LVAD-LV interaction and, ultimately, clinical outcomes in the HM3 population. CLINICAL TRIAL REGISTRATION https://clinicaltrials.gov/ct2/show/NCT03255928. CLINICALTRIALSGOV IDENTIFIER NCT03255928.
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Affiliation(s)
| | - Marina Pieri
- Università Vita Salute San Raffaele, Milano
- Department of Anesthesia and Intensive Care, Cardiothoracic Intensive Care Unit, IRCCS San Raffaele Scientific Institute, Milan
| | - Vittorio Pazzanese
- Cardiac Intensive Care Unit, IRCCS San Raffaele Scientific Institute, Milan
| | - Anna Mara Scandroglio
- Department of Anesthesia and Intensive Care, Cardiothoracic Intensive Care Unit, IRCCS San Raffaele Scientific Institute, Milan
| | - Federico Pappalardo
- Cardiothoracic and Vascular Anesthesia and Intensive Care, AO SS. Antonio e Biagio e Cesare Arrigo, Alessandria, Italy
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28
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Saleh-Abadi M, Rahmati A, Farajollahi A, Fatemi A, Salimi MR. Optimization of geometric indicators of a ventricular pump using computational fluid dynamics, surrogate model, response surface approximation, kriging and particle swarm optimization algorithm. JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING 2023; 45:431. [DOI: 10.1007/s40430-023-04355-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 07/09/2023] [Indexed: 08/28/2023]
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29
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Chassagne F, Beckman JA, Li S, Mahr C, Aliseda A. In Vitro Investigation of the Effect of the Timing of Left Ventricular Assist Device Speed Modulation on Intraventricular Flow Patterns. ASAIO J 2023; 69:533-543. [PMID: 36881637 PMCID: PMC11187697 DOI: 10.1097/mat.0000000000001893] [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: 03/09/2023] Open
Abstract
Thromboembolic events remain a common complication for left ventricular assist device (LVAD) patients. To prevent in-pump thrombosis, third-generation LVADs use speed modulation, which is not synchronized with the native left ventricle (LV) contractility. This study aims to investigate the effect of speed modulation on intraventricular flow patterns, and specifically, the impact of timing relative to pressure variations in the LV. Stereo-particle image velocimetry measurements were performed in a patient-derived LV implanted with an LVAD, for different timings of the speed modulation and speed. Speed modulation has a strong effect on instantaneous afterload and flowrate (-16% and +20%). The different timings of the speed modulation resulted in different flowrate waveforms, exhibiting different maxima (5.3-5.9 L/min, at constant average flowrate). Moreover, the timing of the speed modulation was found to strongly influence intraventricular flow patterns, specifically, stagnation areas within the LV. These experiments highlight, once more, the complex relationship between LVAD speed, hemodynamic resistance, and intraventricular pressure. Overall, this study demonstrates the importance of considering native LV contractility in future LVAD controls, to improve hemocompatibility and reduce the risk of thromboembolic complications.
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Affiliation(s)
- Fanette Chassagne
- Mines Saint-Etienne, Univ Jean Monnet, INSERM, U 1059 Sainbiose, F - 42023 Saint-Etienne France
| | | | - Song Li
- Division of Cardiology, University of Washington, Seattle, WA, USA
| | - Claudius Mahr
- Division of Cardiology, University of Washington, Seattle, WA, USA
| | - Alberto Aliseda
- Mechanical Engineering, University of Washington, Seattle, WA, USA
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30
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Numan L, Zimpfer D, Zadok OIB, Aarts E, Morshuis M, Guenther SP, Riebandt J, Wiedemann D, Ramjankhan FZ, Oppelaar A, Ben‐Gal T, Ben‐Avraham B, Asselbergs FW, Schramm R, Van Laake LW. Identifying patients at risk: multi-centre comparison of HeartMate 3 and HeartWare left ventricular assist devices. ESC Heart Fail 2023; 10:1656-1665. [PMID: 36798028 PMCID: PMC10192248 DOI: 10.1002/ehf2.14308] [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: 08/23/2022] [Revised: 12/09/2022] [Accepted: 01/18/2023] [Indexed: 02/18/2023] Open
Abstract
AIMS Since the withdrawal of HeartWare (HVAD) from the global market, there is an ongoing discussion if and which patients require prophylactically exchange for a HeartMate 3 (HM3). Therefore, it is important to study outcome differences between HVAD and HM3 patients. Because centres differ in patient selection and standard of care, we performed a propensity score (PS)-based study including centres that implanted both devices and aimed to identify which HVAD patients are at highest risk. METHODS AND RESULTS We performed an international multi-centre study (n = 1021) including centres that implanted HVAD and HM3. PS-matching was performed using clinical variables and the implanting centre. Survival and complications were compared. As a sensitivity analysis, PS-adjusted Cox regression was performed. Landmark analysis with conditional survival >2 years was conducted to evaluate long-term survival differences. To identify which HVAD patients may benefit from a HM3 upgrade, Cox regression using pre-operative variables and their interaction with device type was performed. Survival was significantly better for HM3 patients (P < 0.01) in 458 matched patients, with a median follow-up of 23 months. Within the matched cohort, HM3 patients had a median age of 58 years, and 83% were male, 80% of the HVAD patients were male, with a median age of 59 years. PS-adjusted Cox regression confirmed a significantly better survival for HM3 patients when compared with HVAD, with a HR of 1.46 (95% confidence interval 1.14-1.85, P < 0.01). Pump thrombosis (P < 0.01) and ischaemic stroke (P < 0.01) occurred less in HM3 patients. No difference was found for haemorrhagic stroke, right heart failure, driveline infection, and major bleeding. Landmark-analysis confirmed a significant difference in conditional survival >2 years after implantation (P = 0.03). None of the pre-operative variable interactions in the Cox regression were significant. CONCLUSIONS HM3 patients have a significantly better survival and a lower incidence of ischaemic strokes and pump thrombosis than HVAD patients. This survival difference persisted after 2 years of implantation. Additional research using post-operative variables is warranted to identify which HVAD patients need an upgrade to HM3 or expedited transplantation.
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Affiliation(s)
- Lieke Numan
- Department of Cardiology, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
| | - Daniel Zimpfer
- Department of Cardiac SurgeryMedical University of ViennaViennaAustria
| | - Osnat Itzhaki Ben Zadok
- Department of CardiologyRabin Medical CenterPetah TikvaIsrael
- Sackler School of MedicineTel‐Aviv UniversityTel‐AvivIsrael
| | - Emmeke Aarts
- Department of Methodology and StatisticsUtrecht UniversityUtrechtThe Netherlands
| | - Michiel Morshuis
- Clinic for Thoracic and Cardiovascular SurgeryHeart and Diabetes Center Northrhine Westfalia, Ruhr‐University BochumBad OeynhausenGermany
| | - Sabina P.W. Guenther
- Clinic for Thoracic and Cardiovascular SurgeryHeart and Diabetes Center Northrhine Westfalia, Ruhr‐University BochumBad OeynhausenGermany
| | - Julia Riebandt
- Department of Cardiac SurgeryMedical University of ViennaViennaAustria
| | - Dominik Wiedemann
- Department of Cardiac SurgeryMedical University of ViennaViennaAustria
| | - Faiz Z. Ramjankhan
- Department of Cardiothoracic Surgery, University Medical Centre UtrechtUniversity of UtrechtUtrechtThe Netherlands
| | - Anne‐Marie Oppelaar
- Department of Cardiothoracic Surgery, University Medical Centre UtrechtUniversity of UtrechtUtrechtThe Netherlands
| | - Tuvia Ben‐Gal
- Department of CardiologyRabin Medical CenterPetah TikvaIsrael
- Sackler School of MedicineTel‐Aviv UniversityTel‐AvivIsrael
| | - Binyamin Ben‐Avraham
- Department of CardiologyRabin Medical CenterPetah TikvaIsrael
- Sackler School of MedicineTel‐Aviv UniversityTel‐AvivIsrael
| | - Folkert W. Asselbergs
- Department of Cardiology, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
- Institute of Cardiovascular Science, Faculty of Population Health SciencesUniversity College LondonLondonUK
- Health Data Research UK and Institute of Health InformaticsUniversity College London222 Euston RoadLondonNW1 2DAUK
- Department of Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical CentreUniversity of AmsterdamAmsterdamThe Netherlands
| | - Rene Schramm
- Clinic for Thoracic and Cardiovascular SurgeryHeart and Diabetes Center Northrhine Westfalia, Ruhr‐University BochumBad OeynhausenGermany
| | - Linda W. Van Laake
- Department of Cardiology, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
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31
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Li P, Mei X, Ge W, Wu T, Zhong M, Huan N, Jiang Q, Hsu PL, Steinseifer U, Dong N, Zhang L. A comprehensive comparison of the in vitro hemocompatibility of extracorporeal centrifugal blood pumps. Front Physiol 2023; 14:1136545. [PMID: 37228828 PMCID: PMC10204736 DOI: 10.3389/fphys.2023.1136545] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 04/20/2023] [Indexed: 05/27/2023] Open
Abstract
Purpose: Blood damage has been associated with patients under temporary continuous-flow mechanical circulatory support. To evaluate the side effects caused by transit blood pumping, in vitro hemocompatibility testing for blood damage in pumps is considered a necessary reference before clinical trials. Methods: The hemocompatibility of five extracorporeal centrifugal blood pumps was investigated comprehensively, including four commercial pumps (the Abbott CentriMag, the Terumo Capiox, the Medos DP3, and the Medtronic BPX-80) and a pump in development (the magAssist MoyoAssist®). In vitro, hemolysis was tested with heparinized porcine blood at nominal operating conditions (5 L/min, 160 mmHg) and extreme operating conditions (1 L/min, 290 mmHg) using a circulation flow loop. Hematology analyses concerning the blood cell counts and the degradation of high-molecular-weight von Willebrand factor (VWF) during 6-h circulation were also evaluated. Results: Comparing the in vitro hemocompatibility of blood pumps at different operations, the blood damage was significantly more severe at extreme operating conditions than that at nominal operating conditions. The performance of the five blood pumps was arranged in different orders at these two operating conditions. The results also demonstrated superior hemocompatibility of CentriMag and MoyoAssist® at two operating conditions, with overall low blood damage at hemolysis level, blood cell counts, and degradation of high-molecular-weight VWF. It suggested that magnetic bearings have an advantage in hemocompatibility compared to the mechanical bearing of blood pumps. Conclusion: Involving multiple operating conditions of blood pumps in in vitro hemocompatibility evaluation will be helpful for clinical application. In addition, the magnetically levitated centrifugal blood pump MoyoAssist® shows great potential in the future as it demonstrated good in vitro hemocompatibility.
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Affiliation(s)
- Ping Li
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xu Mei
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Wanning Ge
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Tingting Wu
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Min Zhong
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Nana Huan
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Qiubo Jiang
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Po-Lin Hsu
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Ulrich Steinseifer
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Nianguo Dong
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Liudi Zhang
- Artificial Organ Technology Lab, Biomanufacturing Centre, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
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32
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Litvak M, Shamanaev A, Zalawadiya S, Matafonov A, Kobrin A, Feener EP, Wallisch M, Tucker EI, McCarty OJT, Gailani D. Titanium is a potent inducer of contact activation: implications for intravascular devices. J Thromb Haemost 2023; 21:1200-1213. [PMID: 36696212 PMCID: PMC10621279 DOI: 10.1016/j.jtha.2022.12.014] [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: 09/26/2022] [Revised: 12/07/2022] [Accepted: 12/15/2022] [Indexed: 01/09/2023]
Abstract
BACKGROUND Titanium (Ti) and its alloys are widely used in manufacturing medical devices because of their strength and resistance to corrosion. Although Ti compounds are considered compatible with blood, they appear to support plasma contact activation and may be thrombogenic. OBJECTIVES The objective of this study was to compare Ti and titanium nitride (TiN) with known activators of contact activation (kaolin and silica) in plasma-clotting assays and to assess binding and activation of factor XII, (FXII), factor XI (FXI), prekallikrein, and high-molecular-weight kininogen (HK) with Ti/TiN. METHODS Ti-based nanospheres and foils were compared with kaolin, silica, and aluminum in plasma-clotting assays. Binding and activation of FXII, prekallikrein, HK, and FXI to surfaces was assessed with western blots and chromogenic assays. RESULTS Using equivalent surface amounts, Ti and TiN were comparable with kaolin and superior to silica, for inducing coagulation and FXII autoactivation. Similar to many inducers of contact activation, Ti and TiN are negatively charged; however, their effects on FXII are not neutralized by the polycation polybrene. Antibodies to FXII, prekallikrein, or FXI or coating Ti with poly-L-arginine blocked Ti-induced coagulation. An antibody to FXII reduced FXII and PK binding to Ti, kallikrein generation, and HK cleavage. CONCLUSION Titanium compounds induce contact activation with a potency comparable with that of kaolin. Binding of FXII with Ti shares some features with FXII binding to soluble polyanions but may have unique features. Inhibitors targeting FXII or FXI may be useful in mitigating Ti-induced contact activation in patients with titanium-based implants that are exposed to blood.
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Affiliation(s)
- Maxim Litvak
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Aleksandr Shamanaev
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sandip Zalawadiya
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Anton Matafonov
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Anton Kobrin
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Edward P Feener
- KalVista Pharmaceuticals, Inc., Cambridge, Massachusetts, USA
| | - Michael Wallisch
- Aronora, Inc., Portland, Oregon, USA; Department of Biomedical Engineering, Oregon Health & Science University, Oregon, USA
| | - Erik I Tucker
- Aronora, Inc., Portland, Oregon, USA; Department of Biomedical Engineering, Oregon Health & Science University, Oregon, USA
| | - Owen J T McCarty
- Department of Biomedical Engineering, Oregon Health & Science University, Oregon, USA
| | - David Gailani
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
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Bornoff J, Najar A, Fresiello L, Finocchiaro T, Perkins IL, Gill H, Cookson AN, Fraser KH. Fluid-structure interaction modelling of a positive-displacement Total Artificial Heart. Sci Rep 2023; 13:5734. [PMID: 37059748 PMCID: PMC10104863 DOI: 10.1038/s41598-023-32141-2] [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: 12/23/2022] [Accepted: 03/23/2023] [Indexed: 04/16/2023] Open
Abstract
For those suffering from end-stage biventricular heart failure, and where a heart transplantation is not a viable option, a Total Artificial Heart (TAH) can be used as a bridge to transplant device. The Realheart TAH is a four-chamber artificial heart that uses a positive-displacement pumping technique mimicking the native heart to produce pulsatile flow governed by a pair of bileaflet mechanical heart valves. The aim of this work was to create a method for simulating haemodynamics in positive-displacement blood pumps, using computational fluid dynamics with fluid-structure interaction to eliminate the need for pre-existing in vitro valve motion data, and then use it to investigate the performance of the Realheart TAH across a range of operating conditions. The device was simulated in Ansys Fluent for five cycles at pumping rates of 60, 80, 100 and 120 bpm and at stroke lengths of 19, 21, 23 and 25 mm. The moving components of the device were discretised using an overset meshing approach, a novel blended weak-strong coupling algorithm was used between fluid and structural solvers, and a custom variable time stepping scheme was used to maximise computational efficiency and accuracy. A two-element Windkessel model approximated a physiological pressure response at the outlet. The transient outflow volume flow rate and pressure results were compared against in vitro experiments using a hybrid cardiovascular simulator and showed good agreement, with maximum root mean square errors of 15% and 5% for the flow rates and pressures respectively. Ventricular washout was simulated and showed an increase as cardiac output increased, with a maximum value of 89% after four cycles at 120 bpm 25 mm. Shear stress distribution over time was also measured, showing that no more than [Formula: see text]% of the total volume exceeded 150 Pa at a cardiac output of 7 L/min. This study showed this model to be both accurate and robust across a wide range of operating points, and will enable fast and effective future studies to be undertaken on current and future generations of the Realheart TAH.
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Affiliation(s)
- Joseph Bornoff
- Department of Mechanical Engineering, University of Bath, Bath, UK
| | - Azad Najar
- Scandinavian Real Heart AB, Västerås, Sweden
| | - Libera Fresiello
- Faculty of Science and Technology, University of Twente, Twente, The Netherlands
| | | | | | - Harinderjit Gill
- Department of Mechanical Engineering, University of Bath, Bath, UK
- Centre for Therapeutic Innovation, University of Bath, Bath, UK
| | - Andrew N Cookson
- Department of Mechanical Engineering, University of Bath, Bath, UK
- Centre for Therapeutic Innovation, University of Bath, Bath, UK
| | - Katharine H Fraser
- Department of Mechanical Engineering, University of Bath, Bath, UK.
- Centre for Therapeutic Innovation, University of Bath, Bath, UK.
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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.
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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
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Huang F, Lei H, Ying S, Fu Y, Li Q, Ruan X. Numerical hemolysis performance evaluation of a rotary blood pump under different speed modulation profiles. Front Physiol 2023; 14:1116266. [PMID: 36818439 PMCID: PMC9931726 DOI: 10.3389/fphys.2023.1116266] [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: 12/05/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Introduction: Speed modulation methods have been studied and even used clinically to create extra pulsation in the blood circulatory system with the assistance of a continuous flow rotary blood pump. However, fast speed variations may also increase the hemolysis potential inside the pump. Methods: This study investigates the hemolysis performance of a ventricular assist rotary blood pump under sinusoidal, square, and triangular wave speed modulation profiles using the computational fluid dynamics (CFD) method. The CFD boundary pressure conditions of the blood pump were obtained by combining simulations with the pump's mathematical model and a complete cardiovascular lumped parameter model. The hemolysis performance of the blood pump was quantified by the hemolysis index (HI) calculated from a Eulerian scalar transport equation. Results: The HI results were obtained and compared with a constant speed condition when the blood pump was run under three speed profiles. The speed modulations were revealed to slightly affect the pump hemolysis, and the hemolysis differences between the different speed modulation profiles were insignificant. Discussion: This study suggests that speed modulations could be a feasible way to improve the flow pulsatility of rotary blood pumps while not increasing the hemolysis performance.
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Affiliation(s)
- Feng Huang
- School of Mechanical and Energy Engineering, Zhejiang University of Science and Technology, Hangzhou, China,State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, China,*Correspondence: Feng Huang, ; Qipeng Li,
| | - Huan Lei
- School of Mechanical and Energy Engineering, Zhejiang University of Science and Technology, Hangzhou, China
| | - Shunv Ying
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Clinical Research Center for Oral Diseases of Zhejiang Province, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China
| | - Yang Fu
- School of Mechanical and Energy Engineering, Zhejiang University of Science and Technology, Hangzhou, China
| | - Qipeng Li
- School of Mechanical and Energy Engineering, Zhejiang University of Science and Technology, Hangzhou, China,*Correspondence: Feng Huang, ; Qipeng Li,
| | - Xiaodong Ruan
- State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, China
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Tarzia V, Tessari C, Bagozzi L, Bottigliengo D, Fagan D, Fabozzo A, Mastro FR, Pagnin C, Bottio T, Gregori D, Gerosa G. Anticoagulation alone as an effective and safe antithrombotic therapy in LVAD: When less is more. Curr Probl Cardiol 2023; 48:101506. [PMID: 36402214 DOI: 10.1016/j.cpcardiol.2022.101506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022]
Abstract
To evaluate the safety and effectiveness of anticoagulation alone in HeartMate3 patients. According to antithrombotic regimen, patients were divided into 2 groups: Group-1(warfarin+aspirin) and Group-2(warfarin). A comparison of hemocompatibility-related adverse events (HRAEs), hemocompatibility score (HCS), and hemocoagulative laboratory markers, both qualitative and quantitative, between the 2 groups were performed. Fifty patients were enrolled, 28 (56%) in Group-1 and 22 in Group-2 (44%), without statistical differences at baseline. Median time of follow-up was 590 days (IQR: 410.25-1007.50). Eighteen HRAEs (36.0%) occurred: 17 in Group-1 (34%) and 1 in Group-2 (2%) (P < 0.001). The net HCS for Group-1 versus Group-2 was 24 points and 1 point (OR 12.116[2.034-233.226], P = 0.023), respectively. Hemocoagulative values turned into the normality and remained stable during follow-up, without differences between groups, except for ASPI-test (P = 0.003). HeartMate3 showed a high hemocompatibility independently from antithrombotic therapy. Aspirin avoidance resulted a safe and effective strategy since it reduced hemorrhagic events, without increasing thrombotic risk.
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Affiliation(s)
- Vincenzo Tarzia
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy.
| | - Chiara Tessari
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Lorenzo Bagozzi
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Daniele Bottigliengo
- Biostatistics, Epidemiology and Public Health Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Davide Fagan
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Assunta Fabozzo
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Florinda Rosaria Mastro
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Chiara Pagnin
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Tomaso Bottio
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Dario Gregori
- Biostatistics, Epidemiology and Public Health Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
| | - Gino Gerosa
- Cardiac-Surgery-Unit, Department of Cardio-Thoracic-Vascular Sciences and Public Health, University of Padova, Padova, Italy
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Uriel N, Milano C, Agarwal R, Lee S, Cleveland J, Goldstein D, Wang A, Crandall D, Mehra MR. Incidence and clinical correlates of de-novo aortic regurgitation with a fully magnetically levitated left ventricular assist device: a MOMENTUM 3 trial portfolio analysis. Eur J Heart Fail 2023; 25:286-294. [PMID: 36404406 DOI: 10.1002/ejhf.2746] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
AIMS We assessed the incidence, predictors and clinical correlates of de-novo aortic regurgitation (AR), which physiologically reduces left ventricular assist device (LVAD) effectiveness due to recirculation syndrome, in the MOMENTUM 3 trial portfolio of the fully magnetically levitated HeartMate 3 (HM3) pump using the randomized pivotal trial (PT) and post-trial continued access protocol (CAP). METHODS AND RESULTS De-novo aortic regurgitation incidence at 2 years was analysed in the randomized PT and validated in the first 1000 implanted patients of the CAP. Patients with concomitant/prior aortic valve surgery or without baseline or post-implant echocardiograms were excluded from this analysis. AR severity was assessed qualitatively by site-adjudicated echocardiograms (significant AR was defined as moderate or severe grade on echocardiogram). Of 1028 patients enrolled in the PT, 918 were eligible for inclusion in this analysis (HM3, n = 465; HMII, n = 453). At 2 years of LVAD support, freedom from significant AR was greater in the HM3 (92%) than HMII (82%) (hazard ratio 0.45, 95% confidence interval 0.27-0.75, p < 0.01). Of 907 HM3 patients analysed from the first 1000 implanted CAP patients, the rate of freedom from significant AR was 90%, consistent with the PT (p = 0.3). In the combined HM3 group (n = 1372), multivariable Cox modelling identified increasing age and female sex as significant predictors. Survival free of urgent transplant or AR corrective procedure was similar between HM3 patients with and without significant de-novo AR. CONCLUSIONS The development of moderate or severe grade de-novo AR is reduced with the fully magnetically levitated HM3 LVAD compared to the axial-flow HMII pump. The occurrence of significant de-novo AR with the HM3 pump is not associated with a worse outcome at 2 years of follow-up.
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Affiliation(s)
- Nir Uriel
- Division of Cardiology, Columbia University Irving Medical Center, New York, NY, USA
| | - Carmelo Milano
- Division of Cardiothoracic Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA
| | - Richa Agarwal
- Section of Advanced Heart Failure and Cardiac Transplantation, Division of Cardiology, Duke University Medical Center, Durham, NC, USA
| | - Sangjin Lee
- Division of Medicine, Advanced Heart Failure and Transplantation, Spectrum Health Meijer Heart & Vascular Institute, Grand Rapids, MI, USA
| | - Joseph Cleveland
- Division of Cardiothoracic Surgery, Department of Surgery, University of Colorado Health Sciences Center, Aurora, CO, USA
| | - Daniel Goldstein
- Department of Cardiovascular and Thoracic Surgery, Montefiore Einstein Center for Heart and Vascular Care, Bronx, NY, USA
| | - AiJia Wang
- Clinical Biostatistics - Heart Failure, Abbott, Burlington, MA, USA
| | - Daniel Crandall
- Global Clinical Affairs - Heart Failure, Abbott, Pleasanton, CA, USA
| | - Mandeep R Mehra
- Heart and Vascular Center, Center for Advanced Heart Disease, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Fang P, Yang Y, Wei X, Yu S. Preclinical evaluation of the fluid dynamics and hemocompatibility of the Corheart 6 left ventricular assist device. Artif Organs 2023. [PMID: 36625490 DOI: 10.1111/aor.14498] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/24/2022] [Accepted: 01/04/2023] [Indexed: 01/11/2023]
Abstract
BACKGROUND Corheart 6 (Corheart) is a newly developed magnetically levitated continuous-flow left ventricular assist device currently undergoing multicenter clinical trials in China. Featuring a small size, minimal weight, and low power consumption, the Corheart aims to improve pump hemocompatibility, reduce adverse events, and enhance the quality of life of heart failure patients. METHODS Computational simulations assessed flow field, shear stress, and washout, while in vitro and in vivo experiments were performed to further demonstrate hemocompatibility. RESULTS Numerical results show that the flow path in the Corheart blood pump is well designed. There is no significantly high shear stress in the majority of the flow domain. Short secondary flow paths and small pump size (small priming volume) provide good washing (0.049 and 0.165 s to remove 55% and 95% old blood, respectively), allowing low hemolysis levels both in computational and in vitro hemolysis tests (in vitro hemolysis index ranges from 0.00092 ± 0.00006 g/100 L to 0.00134 ± 0.00019 g/100 L). Good hemocompatibility was further evidenced by ten 60-day sheep implants tested with relatively low flow rates of 2.0 ± 0.2 L/min; the results showed no hemolysis or thrombosis. CONCLUSIONS Numerical and experimental results shed light on the fluid dynamics characteristics and hemocompatibility of the Corheart. It is believed that the Corheart will provide more promising possibilities for minimally invasive implantation techniques and for those patients with a small body surface area.
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Affiliation(s)
- Peng Fang
- School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, China
| | - Yuzhuo Yang
- Shenzhen Core Medical Technology Co, Ltd, Shenzhen, China
| | - Xufeng Wei
- Department of Cardiac Surgery, Wuxi Mingci Cardiovascular Hospital, Wuxi, China
| | - Shunzhou Yu
- Shenzhen Core Medical Technology Co, Ltd, Shenzhen, China
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Chan CHH, Murashige T, Bieritz SA, Semenzin C, Smith A, Leslie L, Simmonds MJ, Tansley GD. Mitigation effect of cell exclusion on blood damage in spiral groove bearings. J Biomech 2023; 146:111394. [PMID: 36462474 DOI: 10.1016/j.jbiomech.2022.111394] [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: 04/26/2022] [Revised: 11/10/2022] [Accepted: 11/16/2022] [Indexed: 11/27/2022]
Abstract
Cell exclusion in spiral groove bearing (SGB) excludes red blood cells from high shear regions in the bearing gaps and potentially reduce haemolysis in rotary blood pumps. However, this mechanobiological phenomenon has been observed in ultra-low blood haematocrit only, whether it can mitigate blood damage in a clinically-relevant blood haematocrit remains unknown. This study examined whether cell exclusion in a SGB alters haemolysis and/or high-molecular-weight von Willebrand factor (HMW vWF) multimer degradation. Citrated human blood was adjusted to 35 % haematocrit and exposed to a SGB (n = 6) and grooveless disc (n = 3, as a non-cell exclusion control) incorporated into a custom-built Couette test rig operating at 2000RPM for an hour; shearing gaps were 20, 30, and 40 μm. Haemolysis was assessed via spectrophotometry and HMW vWF multimer degradation was detected with gel electrophoresis and immunoblotting. Haemolysis caused by the SGB at gaps of 20, 30 and 40 μm were 10.6 ± 3.3, 9.6 ± 2.7 and 10.5 ± 3.9 mg/dL.hr compared to 23.3 ± 2.6, 12.8 ± 3.2, 9.8 ± 1.8 mg/dL.hr by grooveless disc. At the same shearing gap of 20 µm, there was a significant reduced in haemolysis (P = 0.0001) and better preserved in HMW vWF multimers (p < 0.05) when compared SGB to grooveless disc. The reduction in blood damage in the SGB compared to grooveless disc is indicative of cell exclusion occurred at the gap of 20 µm. This is the first experimental study to demonstrate that cell exclusion in a SGB mitigates the shear-induced blood damage in a clinically-relevant blood haematocrit of 35 %, which can be potentially utilised in future blood pump design.
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Affiliation(s)
- Chris Hoi Houng Chan
- School of Engineering and Built Environment, Griffith University, Queensland, Australia; Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia.
| | - Tomotaka Murashige
- School of Engineering and Built Environment, Griffith University, Queensland, Australia; School of Engineering, Tokyo Institute of Technology, Meguro, Japan
| | - Shelby A Bieritz
- School of Engineering and Built Environment, Griffith University, Queensland, Australia; Department of Bioengineering, Rice University, Houston, TX, USA
| | - Clayton Semenzin
- School of Engineering and Built Environment, Griffith University, Queensland, Australia; Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
| | - Amanda Smith
- Menzies Health Institute Queensland, Griffith University, Queensland, Australia
| | - Laura Leslie
- Mechanical, Biomedical and Design Group, Aston University, Birmingham, UK
| | - Michael J Simmonds
- Menzies Health Institute Queensland, Griffith University, Queensland, Australia
| | - Geoff D Tansley
- School of Engineering and Built Environment, Griffith University, Queensland, Australia; Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
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40
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Biological Response to Sintered Titanium in Left Ventricular Assist Devices: Pseudoneointima, Neointima, and Pannus. ASAIO J 2023; 69:1-10. [PMID: 35649199 DOI: 10.1097/mat.0000000000001777] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Titanium alloys have traditionally been used in blood-contacting cardiovascular devices, including left ventricular assist devices (LVADs). However, titanium surfaces are susceptible to adverse coagulation, leading to thrombogenesis and stroke. To improve hemocompatibility, LVAD manufacturers introduced powder sintering on blood-wetted surfaces in the 1980s to induce endothelialization. This technique has been employed in multiple contemporary LVADs on the pump housing, as well as the interior and exterior of the inflow cannula. Despite the wide adoption of sintered titanium, reported biologic response over the past several decades has been highly variable and apparently unpredictable-including combinations of neointima, pseudoneoimtima, thrombus, and pannus. We present a history of sintered titanium used in LVAD, a review of accumulated clinical outcomes, and a synopsis of gross appearance and composition of various depositions found clinically and in animal studies, which is unfortunately confounded by the variability and inconsistency in terminology. Therefore, this review endeavors to introduce a unified taxonomy to harmonize published observations of biologic response to sintered titanium in LVADs. From these data, we are able to deduce the natural history of the biologic response to sintered titanium, toward development of a deterministic model of the genesis of a hemocompatible neointima.
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Schlagenhauf A, Haidl H, Trummer G, Berchtold-Herz M, Pooth JS, Strini T, Geisen U, Beyersdorf F, Zieger B. The endogenous thrombin potential in patients with left ventricular assist device or heart transplant. Front Med (Lausanne) 2023; 10:1155496. [PMID: 37122335 PMCID: PMC10130672 DOI: 10.3389/fmed.2023.1155496] [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: 01/31/2023] [Accepted: 03/23/2023] [Indexed: 05/02/2023] Open
Abstract
Background The Heartmate 3 (HM 3) is a left ventricular assist device featuring less shear stress, milder acquired von Willebrand syndrome, and fewer bleeding incidences than its predecessor the Heartmate II (HM II). The novel surface coating of the HM 3 suggests less contact activation of plasmatic coagulation. We hypothesized that patients with HM 3 exhibit fewer aberrations in their thrombin potential than patients with HM II. We compared these results with the thrombin potential of patients with heart transplantation (HTX). Methods Thrombin generation in plasma samples of patients with HM II (n = 16), HM 3 (n = 20), and HTX (n = 13) was analyzed 3 days after implantation/transplantation and after long-term support (3-24 months) with HM II (n = 16) or HM 3 (n = 12) using calibrated automated thrombography. Heparin in postoperative samples was antagonized with polybrene. Results Three days postoperatively HM II patients exhibited a lower endogenous thrombin potential (ETP) than HM 3 and HTX patients (HM II: 947 ± 291 nM*min; HM 3: 1231 ± 176 nM*min; HTX: 1376 ± 162 nM*min, p < 0.001) and a lower velocity index of thrombin generation (HM II: 18.74 ± 10.90 nM/min; HM 3: 32.41 ± 9.51 nM/min; HTX: 37.65 ± 9.41 nM/min, p < 0.01). Subtle differences in the thrombin generation profiles remained in HM II and HM 3 patients under long-term support (Velocity Index: HM II: 38.70 ± 28.46 nM/min; HM 3: 73.32 ± 32.83 nM/min, p < 0.05). Prothrombin fragments 1 + 2 were higher in HM II than in HM 3 patients (HM II: 377.7 ± 208.4 pM; HM 3: 202.1 ± 87.7 pM, p < 0.05) and correlated inversely with the ETP (r = -0.584, p < 0.05). Conclusion We observed a more aberrant thrombin generation in HM II than in HM 3 despite comparable anticoagulation and routine parameters. A trend toward lower values was still observable in HM 3 compared to HTX patients. Calibrated automated thrombography may be a good tool to monitor the coagulation state of these patients and guide anticoagulation in the future.
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Affiliation(s)
- Axel Schlagenhauf
- Department of Pediatrics and Adolescent Medicine, Division of General Pediatrics, Medical University Graz, Graz, Austria
| | - Harald Haidl
- Department of Pediatrics and Adolescent Medicine, Division of General Pediatrics, Medical University Graz, Graz, Austria
| | - Georg Trummer
- Department of Cardiovascular Surgery, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michael Berchtold-Herz
- Department of Cardiovascular Surgery, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jan-Steffen Pooth
- Department of Emergency Medicine, Faculty of Medicine, Medical Center-University of Freiburg, Freiburg im Breisgau, Germany
| | - Tanja Strini
- Department of Pediatrics and Adolescent Medicine, Division of General Pediatrics, Medical University Graz, Graz, Austria
| | - Ulrich Geisen
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Friedhelm Beyersdorf
- Department of Cardiovascular Surgery, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Barbara Zieger
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- *Correspondence: Barbara Zieger,
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Chaudhry S, DeVore AD, Vidula H, Nassif M, Mudy K, Birati EY, Gong T, Atluri P, Pham D, Sun B, Bansal A, Najjar SS. Left Ventricular Assist Devices: A Primer For the General Cardiologist. J Am Heart Assoc 2022; 11:e027251. [PMID: 36515226 PMCID: PMC9798797 DOI: 10.1161/jaha.122.027251] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Durable implantable left ventricular assist devices (LVADs) have been shown to improve survival and quality of life for patients with stage D heart failure. Even though LVADs remain underused overall, the number of patients with heart failure supported with LVADs is steadily increasing. Therefore, general cardiologists will increasingly encounter these patients. In this review, we provide an overview of the field of durable LVADs. We discuss which patients should be referred for consideration of advanced heart failure therapies. We summarize the basic principles of LVAD care, including medical and surgical considerations. We also discuss the common complications associated with LVAD therapy, including bleeding, infections, thrombotic issues, and neurologic events. Our goal is to provide a primer for the general cardiologist in the recognition of patients who could benefit from LVADs and in the principles of managing patients with LVAD. Our hope is to "demystify" LVADs for the general cardiologist.
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Affiliation(s)
- Sunit‐Preet Chaudhry
- Division of CardiologyAscension St. Vincent Heart CenterIndianapolisIN,Ascension St. Vincent Cardiovascular Research InstituteIndianapolisIN
| | - Adam D. DeVore
- Department of Medicine and Duke Clinical Research InstituteDuke University School of MedicineDurhamNC
| | - Himabindu Vidula
- Division of Heart Failure and TransplantUniversity of Rochester School of Medicine and DentistryRochesterNY
| | - Michael Nassif
- Division of Heart failure and TransplantSaint Luke’s Mid America Heart InstituteKansas CityMO
| | - Karol Mudy
- Division of Cardiothoracic SurgeryMinneapolis Heart InstituteMinneapolisMN
| | - Edo Y. Birati
- The Lydia and Carol Kittner, Lea and Benjamin Davidai Division of Cardiovascular Medicine and SurgeryPadeh‐Poriya Medical Center, Bar Ilan UniversityPoriyaIsrael
| | - Timothy Gong
- Center for Advanced Heart and Lung DiseaseBaylor Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical CenterDallasTX
| | - Pavan Atluri
- Division of Cardiovascular SurgeryUniversity of PennsylvaniaPhiladelphiaPA
| | - Duc Pham
- Center for Advanced Heart FailureBluhm Cardiovascular Institute, Northwestern University, Feinberg School of MedicineChicagoIL
| | - Benjamin Sun
- Division of Cardiothoracic Surgery, Abbott Northwestern HospitalMinneapolisMN
| | - Aditya Bansal
- Division of Cardiothoracic Surgery, Department of SurgeryOchsner Clinic FoundationNew OrleansLA
| | - Samer S. Najjar
- Division of Cardiology, MedStar Heart and Vascular InstituteMedstar Medical GroupBaltimoreMD
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43
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Hwang NC, Sivathasan C. Preoperative Evaluation and Care of Heart Transplant Candidates. J Cardiothorac Vasc Anesth 2022; 36:4161-4172. [PMID: 36028377 DOI: 10.1053/j.jvca.2022.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 06/20/2022] [Accepted: 07/08/2022] [Indexed: 11/11/2022]
Abstract
Heart transplantation is recommended for patients with advanced heart failure refractory to medical and device therapy, and who do not have absolute contraindications. When patients become eligible for heart transplantation, they undergo comprehensive evaluation and preparation to optimize their posttransplantation outcomes. This review provides an overview of the processes that are employed to enable the candidates to be transplant-ready when donor hearts are available.
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Affiliation(s)
- Nian Chih Hwang
- Department of Anaesthesiology, Singapore General Hospital, Singapore; Department of Cardiothoracic Anaesthesia, National Heart Centre, Singapore.
| | - Cumaraswamy Sivathasan
- Mechanical Cardiac Support and Heart Transplant Program, Department of Cardiothoracic Surgery, National Heart Centre, Singapore
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44
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Rubinstein G, Lotan D, Moeller CM, DeFilippis EM, Slomovich S, Oren D, Yuzefpolskaya M, Sayer G, Uriel N. Sex differences in patients undergoing heart transplantation and LVAD therapy. Expert Rev Cardiovasc Ther 2022; 20:881-894. [PMID: 36409479 DOI: 10.1080/14779072.2022.2149493] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Left ventricular assist device (LVAD) and heart transplantation (HT) are the two life-sustaining therapies that have revolutionized the management of end-stage heart failure (HF). Yet, significant sex differences exist with respect to their use and effects. AREAS COVERED This review summarizes sex differences in the utilization, outcomes, and complications of LVAD and HT. Particular emphasis is placed on leading clinical trials in the field, historical and recent large registries-based analyses, as well as contemporary technological and policy changes affecting these differences. EXPERT OPINION Women with advanced HF remain under-treated with guideline-directed medical therapy and are less likely to be referred for consideration for LVAD and HT. This remains true despite newer LVAD technology and the new heart transplant allocation system. Community outreach, education, as well as increased representation of women in clinical research may reduce inequities.
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Affiliation(s)
- Gal Rubinstein
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Dor Lotan
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Cathrine M Moeller
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Ersilia M DeFilippis
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Sharon Slomovich
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Daniel Oren
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Melana Yuzefpolskaya
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Gabriel Sayer
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
| | - Nir Uriel
- Division of Cardiology, Center of Advance Cardiac Care, Columbia University Irving Medical Center/New York-Presbyterian Hospital New York, New York, NY, USA
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45
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Goodman D, Stulak J, Rosenbaum AN. Left ventricular assist devices: A historical perspective at the intersection of medicine and engineering. Artif Organs 2022; 46:2343-2360. [PMID: 35929377 DOI: 10.1111/aor.14371] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/06/2022] [Accepted: 07/18/2022] [Indexed: 11/26/2022]
Abstract
Over the last half-century, left ventricular assist device (LVAD) technology has progressed from conceptual therapy for failed cardiopulmonary bypass weaning to an accepted destination therapy for advanced heart failure. The history of LVAD engineering is defined by an initial development phase, which demonstrated the feasibility of such an approach, to the more recent three major generations of commercial devices. In this review, we explore the engineering challenges of LVADs, how they were addressed over time, and the clinical outcomes that resulted from each major technological development. The first generation of commercial LVADs were pulsatile devices, which lacked the appropriate durability due to their number of moving components and hemocompatibility. The second generation of LVADs was defined by replacement of complex, pulsatile pumps with primarily axial, continuous-flow systems with an impeller in the blood passageway. These devices experienced significant commercial success, but the presence of excessive trauma to the blood and in-situ bearing resulted in an unacceptable burden of adverse events. Third generation centrifugal-flow pumps use magnetically suspended rotors within the pump chamber. Superior outcomes with this newest generation of devices have been observed, particularly with respect to hemocompatibility-related adverse events including pump thrombosis, with fully magnetically levitated devices. The future of LVAD engineering includes wireless charging foregoing percutaneous drivelines and more advanced pump control mechanisms, including synchronization of the pump flow with the native cardiac cycle, and varying pump output based on degree of physical exertion using sensor or advanced device-level data triggers.
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Affiliation(s)
- Daniel Goodman
- College of Osteopathic Medicine, Des Moines University, Des Moines, Iowa, USA
| | - John Stulak
- Division of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Andrew N Rosenbaum
- Department of Cardiovascular Diseases, Mayo Clinic Minnesota, Rochester, Minnesota, USA
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Vidula H, Takeda K, Estep JD, Silvestry SC, Milano C, Cleveland JC, Goldstein DJ, Uriel N, Kormos RL, Dirckx N, Mehra MR. Hospitalization Patterns and Impact of a Magnetically-Levitated Left Ventricular Assist Device in the MOMENTUM 3 Trial. JACC. HEART FAILURE 2022; 10:470-481. [PMID: 35772857 DOI: 10.1016/j.jchf.2022.03.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/22/2022] [Accepted: 03/31/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND In the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) pivotal trial, the HeartMate 3 (HM3) fully magnetically levitated left ventricular assist device (LVAD) demonstrated superiority over the axial-flow HeartMate II (HMII) LVAD. The patterns and predictors of hospitalizations with the HM3 LVAD have not been characterized. OBJECTIVES This study sought to determine causes, predictors, and impact of hospitalizations during LVAD support. METHODS Patients discharged after LVAD implantation were analyzed. In the pivotal trial, 485 recipients of HM3 were compared with 471 recipients of HMII. The pivotal trial HM3 group was also compared to 949 recipients of HM3 in the postapproval phase within the trial portfolio. Predictors of cause-specific rehospitalization were analyzed. RESULTS The rates of rehospitalization were lower with HM3 LVAD than with HMII LVAD in the pivotal trial (225.7 vs 246.4 events per 100 patient-years; P < 0.05). Overall, rehospitalization rates and duration were similar in the HM3 postapproval phase and pivotal trial but prolonged hospitalizations (>7 days) were less frequent (rate ratio: 0.90 [95% CI: 0.80-0.98]; P < 0.05). In HM3 recipients, the most frequent causes of rehospitalization included infection, heart failure (HF)-related events, and bleeding. First rehospitalization caused by HF-related event versus other causes was associated with reduced survival (HR: 2.2 [95% CI: 1.3-3.9]; P = 0.0014). Male sex, non-White race, presence of cardiac resynchronization therapy/implantable cardioverter-defibrillator, obesity, higher right atrial pressure, smaller LV size, longer duration of index hospitalization, and lower estimated glomerular filtration rate at index discharge predicted HF hospitalizations. CONCLUSIONS Contemporary support with the HM3 fully magnetically levitated LVAD is associated with a lower hospitalization burden than with prior pumps; however, rehospitalizations for infection, HF, and bleeding remain important challenges for progress in the patient journey. (MOMENTUM 3 IDE Clinical Study, NCT02224755; MOMENTUM 3 Continued Access Protocol [MOMENTUM 3 CAP], NCT02892955).
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Affiliation(s)
- Himabindu Vidula
- Division of Cardiology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Koji Takeda
- Division of Cardiac, Thoracic, and Vascular Surgery, Columbia University College of Physicians and Surgeons and New York-Presbyterian Hospital, New York, New York, USA
| | - Jerry D Estep
- Kaufman Center for Heart Failure and Recovery, The Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Scott C Silvestry
- Thoracic Transplant, Thoracic, and Cardiovascular Surgery Program, AdventHealth Transplant Institute, Orlando, Florida, USA
| | - Carmelo Milano
- Division of Cardiothoracic Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Joseph C Cleveland
- Division of Cardiothoracic Surgery, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Daniel J Goldstein
- Department of Cardiothoracic Surgery, Montefiore Einstein Center for Heart and Vascular Care, New York, New York, USA
| | - Nir Uriel
- Division of Cardiology, Columbia University College of Physicians and Surgeons and New York-Presbyterian Hospital, New York, New York, USA
| | | | | | - Mandeep R Mehra
- Center for Advanced Heart Disease, Brigham and Women's Hospital Heart and Vascular Center and Harvard Medical School, Boston, Massachusetts, USA.
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47
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Comparison of the Hemocompatibility of an Axial and a Centrifugal Left Ventricular Assist Device in an In Vitro Test Circuit. J Clin Med 2022; 11:jcm11123431. [PMID: 35743501 PMCID: PMC9225365 DOI: 10.3390/jcm11123431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/08/2022] [Accepted: 06/13/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Hemocompatibility of left ventricular assist devices is essential for preventing adverse events. In this study, we compared the hemocompatibility of an axial-flow (Sputnik) to a centrifugal-flow (HeartMate 3) pump. METHODS Both pumps were integrated into identical in vitro test circuits, each filled with 75 mL heparinized human blood of the same donor. During each experiment (n = 7), the pumps were operated with equal flow for six hours. Blood sampling and analysis were performed on a regular schedule. The analytes were indicators of hemolysis, coagulation activation, platelet count and activation, as well as extracellular vesicles. RESULTS Sputnik induced higher hemolysis compared to the HeartMate 3 after 360 min. Furthermore, platelet activation was higher for Sputnik after 120 min onward. In the HeartMate 3 circuit, the platelet count was reduced within the first hour. Furthermore, Sputnik triggered a more pronounced increase in extracellular vesicles, a potential trigger for adverse events in left ventricular assist device application. Activation of coagulation showed a time-dependent increase, with no differences between both groups. CONCLUSIONS This experimental study confirms the hypothesis that axial-flow pumps may induce stronger hemolysis compared to centrifugal pumps, coming along with larger amounts of circulating extracellular vesicles and a stronger PLT activation.
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HVAD to HeartMate 3 Left Ventricular Assist Device Exchange: Best Practices Recommendations. Ann Thorac Surg 2022; 113:1770-1777. [PMID: 35341592 DOI: 10.1016/j.athoracsur.2021.11.078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/10/2021] [Indexed: 11/22/2022]
Abstract
The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.
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49
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Outcomes in Smaller Body Size Adults after HeartMate 3 Left Ventricular Assist Device Implantation. Ann Thorac Surg 2022; 114:2262-2269. [PMID: 35452663 DOI: 10.1016/j.athoracsur.2022.03.071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/21/2022] [Accepted: 03/28/2022] [Indexed: 11/23/2022]
Abstract
BACKGROUND Outcomes in patients with smaller body size following HeartMate 3 Left Ventricular Assist Device (HM3) implantation are not well characterized. We sought to evaluate outcomes in smaller vs. larger BSA patients in the MOMENTUM 3 pivotal trial and its Continued Access Protocol cohort. METHODS The analysis cohort included 1015 HM3 patients divided into 2 groups: BSA≤1.70 m2 (small patients, n=82) and BSA>1.70 m2 (large patients, n=933). The composite primary endpoint was survival at 2-years free of disabling stroke or reoperation to replace or remove a malfunctioning device. Adverse events were compared between groups. RESULTS Smaller patients were more frequently women (56.1% vs. 17.7%, P<.001), had lower prevalence of diabetes (28.1% vs. 43.9%, P=.005) and hypertension (51.2% vs. 71.9%, P<.001), larger median indexed LVEDD (normalized by BSA, 40 vs. 33 mm/m2, P<.001), and lower median serum creatinine (1.1 vs. 1.3 mg/dl, P<.001). The proportion of patients achieving the composite endpoint at 2-years was 77% in both groups (adjusted HR = 1.14 [95% confidence interval: 0.68-1.91], P=.62). Two-year adverse event rates were also similar between groups except for sepsis (6.1% vs. 14.9%, P=.029) and cardiac arrhythmias (24.4% vs. 35.3%, P=.005), which were higher in the larger patients. CONCLUSIONS Outcomes following HM3 implantation were comparable between small and large patients. Smaller body size should not be used to deny HM3 implantation in patients who are otherwise suitable durable MCS candidates.
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50
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Salerno CT, Hayward C, Hall S, Goldstein D, Saeed D, Schmitto J, Kaczorowski D, Molina E, Zimpfer D, Tsui S, Soltesz E, Pham DT, Mokadam NA, Kilic A, Davis E, Feller E, Lorts A, Silvestry S, Slaughter MS, Potapov E, Atluri P, Cowger J, Pagani FD. HVAD to HeartMate 3 left ventricular assist device exchange: Best practices recommendations. J Thorac Cardiovasc Surg 2022; 163:2120-2127.e5. [PMID: 35341579 DOI: 10.1016/j.jtcvs.2021.11.085] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 11/29/2022]
Abstract
The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.
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Affiliation(s)
| | | | - Shelley Hall
- Departments of Cardiology and Transplantation, Baylor University Medical Center, Dallas, Tex
| | - Daniel Goldstein
- Department of Cardiothoracic Surgery, Montefiore Medical Center, New York, NY
| | - Diyar Saeed
- Department of Cardiac Surgery, Leipzig Heart Center, Leipzig, Germany
| | | | - David Kaczorowski
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pa
| | - Ezequiel Molina
- Department of Cardiac Surgery, MedStar Washington Hospital Center, Washington, DC
| | - Daniel Zimpfer
- Department of Cardiac Surgery, Medical University Vienna, Vienna, Austria
| | - Steven Tsui
- Department of Cardiothoracic Surgery, Royal Papworth Hospital, Cambridge, United Kingdom
| | - Edward Soltesz
- Department of Cardiothoracic Surgery, Cleveland Clinical Hospital, Cleveland, Ohio
| | - Duc Thin Pham
- Division of Cardiac Surgery, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Nahush A Mokadam
- Division of Cardiac Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Arman Kilic
- Division of Cardiothoracic Surgery, Medical University of South Carolina, Charleston, SC
| | - Erin Davis
- Division of Cardiothoracic Surgery, University of Utah, Salt Lake City, Utah
| | - Erika Feller
- Divison of Cardiovascular Medicine, University of Maryland, Baltimore, Md
| | - Angela Lorts
- Division of Pediatric Cardiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | | | - Mark S Slaughter
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, Ky
| | - Evgenij Potapov
- Department of Thoracic and Cardiovascular Surgery, German Heart Centre, Berlin, Germany
| | - Pavan Atluri
- Division of Cardiovascular Surgery, University of Pennsylvania, Philadelphia, Pa
| | - Jennifer Cowger
- Cardiovascular Medicine, Henry Ford Medical Center, Detroit, Mich
| | - Francis D Pagani
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich.
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