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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] [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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Mondal S, Sankova S, Lee K, Sorensen E, Kaczorowski D, Mazzeffi M. Intraoperative and Early Postoperative Management of Patients Undergoing Minimally Invasive Left Ventricular Assist Device Implantation. J Cardiothorac Vasc Anesth 2020; 35:616-630. [PMID: 32505605 DOI: 10.1053/j.jvca.2020.04.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/03/2020] [Accepted: 04/09/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Samhati Mondal
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD
| | - Susan Sankova
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD
| | - Khang Lee
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD
| | - Erik Sorensen
- Department of Surgery, Division of Cardiothoracic Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - David Kaczorowski
- Department of Surgery, Division of Cardiothoracic Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Michael Mazzeffi
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD.
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Kormos RL, McCall M, Althouse A, Lagazzi L, Schaub R, Kormos MA, Zaldonis JA, Sciortino C, Lockard K, Kuntz N, Dunn E, Teuteberg JJ. Left Ventricular Assist Device Malfunctions. Circulation 2017; 136:1714-1725. [DOI: 10.1161/circulationaha.117.027360] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 06/20/2017] [Indexed: 11/16/2022]
Affiliation(s)
- Robert L. Kormos
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Michael McCall
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Andrew Althouse
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Luigi Lagazzi
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Richard Schaub
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Michael A. Kormos
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Jared A. Zaldonis
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Christopher Sciortino
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Kathleen Lockard
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Nicole Kuntz
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Elizabeth Dunn
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
| | - Jeffrey J. Teuteberg
- From Heart and Vascular Institute (R.L.K., A.A., L.L., C.S., J.J.T.); Artificial Heart Program (M.C., R.S., K.L., N.K., E.D.), University of Pittsburgh Medical Center, PA; Department of Bioengineering, Rochester Institute of Technology, NY (M.A.K.); and Department of Engineering, University of Pittsburgh, PA (J.A.Z.)
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Cook JL, Colvin M, Francis GS, Grady KL, Hoffman TM, Jessup M, John R, Kiernan MS, Mitchell JE, Pagani FD, Petty M, Ravichandran P, Rogers JG, Semigran MJ, Toole JM. Recommendations for the Use of Mechanical Circulatory Support: Ambulatory and Community Patient Care: A Scientific Statement From the American Heart Association. Circulation 2017; 135:e1145-e1158. [PMID: 28559233 DOI: 10.1161/cir.0000000000000507] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Capoccia M. Mechanical Circulatory Support for Advanced Heart Failure: Are We about to Witness a New "Gold Standard"? J Cardiovasc Dev Dis 2016; 3:E35. [PMID: 29367578 PMCID: PMC5715724 DOI: 10.3390/jcdd3040035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 12/03/2016] [Accepted: 12/06/2016] [Indexed: 01/08/2023] Open
Abstract
The impact of left ventricular assist devices (LVADs) for the treatment of advanced heart failure has played a significant role as a bridge to transplant and more recently as a long-term solution for non-eligible candidates. Continuous flow left ventricular assist devices (CF-LVADs), based on axial and centrifugal design, are currently the most popular devices in view of their smaller size, increased reliability and higher durability compared to pulsatile flow left ventricular assist devices (PF-LVADs). The trend towards their use is increasing. Therefore, it has become mandatory to understand the physics and the mathematics behind their mode of operation for appropriate device selection and simulation set up. For this purpose, this review covers some of these aspects. Although very successful and technologically advanced, they have been associated with complications such as pump thrombosis, haemolysis, aortic regurgitation, gastro-intestinal bleeding and arterio-venous malformations. There is perception that the reduced arterial pulsatility may be responsible for these complications. A flow modulation control approach is currently being investigated in order to generate pulsatility in rotary blood pumps. Thrombus formation remains the most feared complication that can affect clinical outcome. The development of a preoperative strategy aimed at the reduction of complications and patient-device suitability may be appropriate. Patient-specific modelling based on 3D reconstruction from CT-scan combined with computational fluid dynamic studies is an attractive solution in order to identify potential areas of stagnation or challenging anatomy that could be addressed to achieve the desired outcome. The HeartMate II (axial) and the HeartWare HVAD (centrifugal) rotary blood pumps have been now used worldwide with proven outcome. The HeartMate III (centrifugal) is now emerging as the new promising device with encouraging preliminary results. There are now enough pumps on the market: it is time to focus on the complications in order to achieve the full potential and selling-point of this type of technology for the treatment of the increasing heart failure patient population.
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Affiliation(s)
- Massimo Capoccia
- Scottish National Advanced Heart Failure Service, Golden Jubilee National Hospital, Glasgow G81 4DY, UK.
- Biomedical Engineering, University of Strathclyde, Glasgow G4 0NW, UK.
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Grimm JC, Magruder JT, Crawford TC, Fraser CD, Plum WG, Sciortino CM, Higgins RS, Whitman GJ, Shah AS. Duration of Left Ventricular Assist Device Support Does Not Impact Survival After US Heart Transplantation. Ann Thorac Surg 2016; 102:1206-12. [DOI: 10.1016/j.athoracsur.2016.04.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/30/2016] [Accepted: 04/06/2016] [Indexed: 10/21/2022]
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Healy AH, McKellar SH, Drakos SG, Koliopoulou A, Stehlik J, Selzman CH. Physiologic effects of continuous-flow left ventricular assist devices. J Surg Res 2016; 202:363-71. [PMID: 27229111 PMCID: PMC4886545 DOI: 10.1016/j.jss.2016.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/10/2016] [Accepted: 01/12/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND Within the past 10 years, continuous-flow left ventricular assist devices (LVADs) have replaced pulsatile-flow LVADs as the standard of care for both destination therapy and bridging patients to heart transplantation. Despite the rapid clinical adoption of continuous-flow LVADs, an understanding of the effects of continuous-flow physiology, as opposed to more natural pulsatile-flow physiology, is still evolving. MATERIALS AND METHODS A thorough review of the relevant scientific literature regarding the physiological and clinical effects of continuous-flow physiology was performed. These effects were analyzed on an organ system basis and include an evaluation of the cardiovascular, respiratory, hematologic, gastrointestinal, renal, hepatic, neurologic, immunologic, and endocrine systems. RESULTS Continuous-flow physiology is, generally speaking, well tolerated over the long term. However, several changes are manifest at the organ system level. Although many of these changes are without appreciable clinical significance, other changes, such as an increased rate of gastrointestinal bleeding, appear to be associated with continuous-flow physiology. CONCLUSIONS Continuous-flow LVADs confer a significant advantage over their pulsatile-flow counterparts with regard to size and durability. From a physiological standpoint, continuous-flow physiology has limited clinical effects at the organ system level. Although improved over previous generations, challenges with this technology remain. Approaching these problems with a combination of clinical and engineering solutions may be needed to achieve continued progression in the field of durable mechanical circulatory support.
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Affiliation(s)
- Aaron H. Healy
- Department of Surgery, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
| | - Stephen H. McKellar
- Department of Surgery, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
| | - Stavros G. Drakos
- Department of Medicine, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
| | - Antigoni Koliopoulou
- Department of Surgery, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
| | - Josef Stehlik
- Department of Medicine, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
| | - Craig H. Selzman
- Department of Surgery, University of Utah, 30 North 1900 East, Salt Lake City, Utah, United States of America
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8
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Left Ventricular Assist Devices: The Adolescence of a Disruptive Technology. J Card Fail 2015; 21:824-34. [PMID: 26318347 DOI: 10.1016/j.cardfail.2015.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 08/19/2015] [Accepted: 08/20/2015] [Indexed: 11/21/2022]
Abstract
Clinical outcomes for patients with advanced heart failure receiving left ventricular assist devices are driven by appropriate patient selection, refined surgical technique, and coordinated medical care. Perhaps even more important is innovative pump design. The introduction and widespread adoption of continuous-flow ventricular assist devices has led to a paradigm shift within the field of mechanical circulatory support, making the promise of lifetime device therapy closer to reality. The disruption caused by this new technology, on the one hand, produced meaningful improvements in patient survival and quality of life, but also introduced new clinical challenges, such as bleeding, pump thrombosis, and acquired valvular heart disease. Further evolution within this field will require financial investment to sustain innovation leading to a fully implantable, durable, and cost-effective pump for a larger segment of patients with advanced heart failure.
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9
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Capoccia M. Development and Characterization of the Arterial Windkessel and Its Role During Left Ventricular Assist Device Assistance. Artif Organs 2015; 39:E138-53. [DOI: 10.1111/aor.12532] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Massimo Capoccia
- Cardiothoracic Surgery; Royal Stoke University Hospital; Stoke-on-Trent UK
- Biomedical Engineering; University of Strathclyde; Glasgow UK
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10
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Abstract
BACKGROUND In recent years, there has been growing interest in evaluating the health and economic impact of medical devices. Payers increasingly rely on cost-effectiveness analyses in making their coverage decisions, and are adopting value-based purchasing initiatives. These analytic approaches, however, have been shaped heavily by their use in the pharmaceutical realm, and are ill-adapted to the medical device context. METHODS This study focuses on the development and evaluation of left ventricular assist devices (LVADs) to highlight the unique challenges involved in the design and conduct of device trials compared with pharmaceuticals. RESULTS Devices are moving targets characterized by a much higher degree of post-introduction innovation and "learning by using" than pharmaceuticals. The cost effectiveness ratio of left ventricular assist devices for destination therapy, for example, decreased from around $600,000 per life year saved based on results from the pivotal trial to around $100,000 within a relatively short time period. CONCLUSIONS These dynamics pose fundamental challenges to the evaluation enterprise as well as the policy-making world, which this paper addresses.
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Lampropulos JF, Kim N, Wang Y, Desai MM, Barreto-Filho JAS, Dodson JA, Dries DL, Mangi AA, Krumholz HM. Trends in left ventricular assist device use and outcomes among Medicare beneficiaries, 2004-2011. Open Heart 2014; 1:e000109. [PMID: 25332817 PMCID: PMC4189322 DOI: 10.1136/openhrt-2014-000109] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 06/27/2014] [Accepted: 07/15/2014] [Indexed: 12/20/2022] Open
Abstract
Objective To characterise the trends in the left ventricular assist device (LVAD) implantation rates and outcomes between 2004 and 2011 in the Medicare population. Since the approval of the HeartMate II in 2008, the use of LVADs has steadily climbed. Given the increase in LVAD use, issues around discharge disposition, post-implant hospitalisations and costs require further understanding. Methods We examined LVAD implantation rates and short-term and long-term outcomes among Medicare fee-for-service beneficiaries hospitalised for LVAD implantation. We also conducted analyses among survivors 1-year post-discharge to examine rehospitalisation rates. Lastly, we reported Centers for Medicare & Medicaid Services (CMS) payments for both index hospitalisation and rehospitalisations 1 year post-discharge. Results A total of 2152 LVAD implantations were performed with numbers increasing from 107 in 2004 to 612 in 2011. The 30-day mortality rate decreased from 52% to 9%, and 1-year mortality rate decreased from 69% to 31%. We observed no change in overall length of stay, but post-procedure length of stay increased. We also found an increase in home discharge dispositions from 26% to 53%. Between 2004 and 2010, the rehospitalisation rate increased and the number of hospital days decreased. The adjusted CMS payment for the index hospitalisation increased from $188 789 to $225 697 over time but decreased for rehospitalisation from $60 647 to $53 630. Conclusions LVAD implantations increased over time. We found decreasing 30-day and 1-year mortality rates and increasing home discharge disposition. The proportion of patients rehospitalised among 1-year survivors remained high with increasing index hospitalisation cost, but decreasing post-implantation costs over time.
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Affiliation(s)
- Julianna F Lampropulos
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Section of Cardiovascular Medicine, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA
| | - Nancy Kim
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Section of General Internal Medicine, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA
| | - Yun Wang
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Section of Cardiovascular Medicine, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA ; Department of Health Care Policy , Harvard Medical School , Boston, Massachusetts , USA
| | - Mayur M Desai
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Department of Chronic Disease Epidemiology , Yale School of Public Health , New Haven, Connecticut , USA
| | - José Augusto S Barreto-Filho
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Division of Cardiology , Federal University of Sergipe , Aracaju, SE , Brazil
| | - John A Dodson
- Leon H. Charney Division of Cardiology, New York University School of Medicine, New York, New York, USA
| | - Daniel L Dries
- Section of Cardiovascular Medicine, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA
| | - Abeel A Mangi
- Section of Cardiac Surgery, Department of Surgery , Yale School of Medicine , New Haven, Connecticut , USA
| | - Harlan M Krumholz
- Center for Outcomes Research and Evaluation , Yale-New Haven Hospital , New Haven, Connecticut , USA ; Section of Cardiovascular Medicine, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA ; Robert Wood Johnson Foundation Clinical Scholars Program, Department of Internal Medicine , Yale School of Medicine , New Haven, Connecticut , USA ; Department of Health Policy and Management , Yale School of Public Health , New Haven, Connecticut , USA
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Slaughter MS. Long-term mechanical circulatory support for advanced heart failure: ‘the tide is turning’. Eur J Heart Fail 2014; 15:1080-1. [DOI: 10.1093/eurjhf/hft137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mark S. Slaughter
- Division of Thoracic and Cardiovascular Surgery; University of Louisville; KY USA
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13
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Morshuis M, Schoenbrodt M, Nojiri C, Roefe D, Schulte-Eistrup S, Boergermann J, Gummert JF, Arusoglu L. DuraHeart™ magnetically levitated centrifugal left ventricular assist system for advanced heart failure patients. Expert Rev Med Devices 2014; 7:173-83. [DOI: 10.1586/erd.09.68] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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La Franca E, Iacona R, Ajello L, Sansone A, Caruso M, Assennato P. Heart failure and mechanical circulatory assist devices. Glob J Health Sci 2013; 5:11-9. [PMID: 23985102 PMCID: PMC4776846 DOI: 10.5539/gjhs.v5n5p11] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 05/06/2013] [Accepted: 04/23/2013] [Indexed: 11/23/2022] Open
Abstract
During the last 20 years, the management of heart failure has significantly improved by means of new pharmacotherapies, more timely invasive treatments and device assisted therapies. Indeed, advances in mechanical support, namely with the development of more efficient left ventricular assist devices (LVAD), and the total artificial heart have reduced mortality and morbidity in patients with end-stage heart failure awaiting for transplantation. However, the transplant cannot be the only solution, due to an insufficient number of available donors, but also because of the high number of patients who are not candidates for severe comorbidities or advanced age. New perspectives are emerging in which the VAD is no longer conceived only as a “Bridge to Transplant”, but is now seen as a destination therapy. In this review, the main VAD classification, current basic indications, functioning modalities, main limitations of surgical VAD and the total artificial heart development are described.
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Huang H, Yang M, Lu C, Xu L, Zhuang X, Meng F. A numerical method to enhance the performance of a cam-type electric motor-driven left ventricular assist device. Artif Organs 2013; 37:875-83. [PMID: 23634991 DOI: 10.1111/aor.12077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pulsatile left ventricular assist devices (LVADs) driven by electric motors have been widely accepted as a treatment of heart failure. Performance enhancement with computer assistance for this kind of LVAD has seldom been reported. In this article, a numerical method is proposed to assist the design of a cam-type pump. The method requires an integrated model of an LVAD system, consisting of a motor, a transmission mechanism, and a cardiovascular circulation. Performance indices, that is, outlet pressure, outlet flow, and pump efficiency, were used to select the best cam profile from six candidates. A prototype pump connected to a mock circulatory loop (MCL) was used to calibrate the friction coefficient of the cam groove and preliminarily evaluate modeling accuracy. In vitro experiments show that the mean outlet pressure and flow can be predicted with high accuracy by the model, and gross geometries of the measurements can also be reproduced. Simulation results demonstrate that as the total peripheral resistance (TPR) is fixed at 1.1 mm Hg.s/mL, the two-cycle 2/3-rise profile is the best. Compared with other profiles, the maximum increases of pressure and flow indices are 75 and 76%, respectively, and the maximum efficiency increase is over 51%. For different TPRs (0.5∼1.5 mm Hg.s/mL) and operation intervals (0.1∼0.4 s) in counterpulsation, the conclusion is also acceptable.
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Affiliation(s)
- Huan Huang
- Department of Instrument Science and Engineering, Shanghai Jiaotong University, Shanghai, China
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Holman WL, Naftel DC, Eckert CE, Kormos RL, Goldstein DJ, Kirklin JK. Durability of left ventricular assist devices: Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) 2006 to 2011. J Thorac Cardiovasc Surg 2013; 146:437-41.e1. [PMID: 23490245 DOI: 10.1016/j.jtcvs.2013.02.018] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 02/12/2013] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The present study compared the interval until device exchange or death from pump-related failure in patients with pulsatile versus continuous flow left ventricular assist devices. METHODS Data from Interagency Registry for Mechanically Assisted Circulatory Support (June 23, 2006, to March 31, 2011) compared the durability of implanted pulsatile and continuous flow left ventricular assist devices. The durability issues included pump replacement for infection, thrombosis-hemolysis, driveline failure, or pump drive unit failure, and death from driveline or pump drive unit failure. RESULTS A total of 3302 left ventricular assist devices were implanted (486 pulsatile, 2816 continuous flow) and 98 pump exchanges or deaths from durability issues (46 pulsatile, 52 continuous flow; 3% of implants). The interval to device issue was greater for the continuous flow than for the pulsatile devices (P < .001). A comparisons of the causes for pump exchange or pump-related death showed (1) greater freedom from pump failure in the continuous flow compared with the pulsatile left ventricular assist devices (10 events/2816 continuous flow implants vs 39 events/486 pulsatile implants; P < .0001); (2) similar exchange or pump-related death for driveline failure (1/486 pulsatile vs 7/2816 continuous flow; P = .82); (3) similar exchange or pump-related death for thrombosis-hemolysis (2/486 pulsatile vs 28/2816 continuous flow; P = .25); and (4) fewer exchanges or pump-related deaths from infection in continuous flow left ventricular assist devices (4/486 pulsatile vs 7/2816 continuous flow; P = .034). Competing outcomes analysis corroborated this finding, with 54% of continuous flow versus 23% of pulsatile patients alive and receiving support at 12 months after implantation. CONCLUSIONS The Analysis of Interagency Registry for Mechanically Assisted Circulatory Support data showed greater durability for continuous flow than for pulsatile left ventricular assist devices. Even longer durations of support can be expected if pump durability continues to improve.
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Affiliation(s)
- William L Holman
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Ala 35294-0007, USA.
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Moazami N, Milano CA, John R, Sun B, Adamson RM, Pagani FD, Smedira N, Slaughter MS, Farrar DJ, Frazier OH. Pump replacement for left ventricular assist device failure can be done safely and is associated with low mortality. Ann Thorac Surg 2012; 95:500-5. [PMID: 23261114 DOI: 10.1016/j.athoracsur.2012.09.011] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 08/28/2012] [Accepted: 09/04/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Although continuous-flow left ventricular assist devices (LVAD) are durable and reliable, device replacement will be inevitable in some patients. We evaluated the incidence and outcomes of pump replacement procedures with the HeartMate II (Thoratec Corporation, Pleasanton, CA) LVAD. METHODS Data were obtained from 1,128 patients implanted from March 2005 to January 2010 with the HeartMate II during the clinical trials for bridge to transplant and destination therapy. The operative mortality associated with the replacement procedure was determined. RESULTS The mean duration of HeartMate II support was 568 ± 535 days (cumulative duration: 1,755 patient-years, longest: 6.5 years). A total of 72 (6.4%) patients underwent 79 LVAD replacements (0.045 events/patient-year) of which 2 were in the initial operation and 77 in separate procedures. Reasons for replacement were percutaneous lead damage (36 events, 3.0%), device thrombosis (25 events, 2.1%), infection (7 events, 0.6%), and miscellaneous other (11 events, 0.9%). The median time to pump replacement was 428 days (range 0 to 1,474). Of the 77 replacement procedures, there were 5 (6.5%) operative deaths within 30 days. The causes of death were device thrombosis, right heart failure, multisystem organ failure, and bleeding. One year after exchange (median 2.1 years after initial implant), 30% had died, 5% were transplanted, and 65% were ongoing and alive. CONCLUSIONS HeartMate II device failure requiring pump replacement is infrequent, but when required can be done safely. These data continue to provide encouraging evidence supporting HeartMate II use for long-term circulatory support.
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Affiliation(s)
- Nader Moazami
- Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, Cleveland, Ohio 44195, USA.
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Lessons learned from experience with over 100 consecutive HeartMate II left ventricular assist devices. Ann Thorac Surg 2011; 92:1593-9; discussion 1599-600. [PMID: 22051256 DOI: 10.1016/j.athoracsur.2011.06.081] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 06/20/2011] [Accepted: 06/22/2011] [Indexed: 12/14/2022]
Abstract
BACKGROUND Continuous-flow left ventricular assist devices (LVADs) such as the HeartMate II have become the therapy of choice in patients with end-stage heart failure. The aim of this study is to report the outcomes in patients receiving the HeartMate II LVAD at a single center and review the lessons learned from this experience. METHODS From June 2005 to June 2010, 130 consecutive patients received the HeartMate II LVAD. Of these, 102 were bridge-to-transplant (BTT), 17 destination therapy, and 11 exchanges for failed HeartMate XVE. This study focuses on the 102 BTT patients. The HeartMate II was approved by the US Food and Drug Administration (FDA) as BTT in April 2008 and 64 patients received this device as BTT since that date. We review our experience with the device as BTT and report on patient survival and adverse events as well as the impact of FDA approval on outcomes. RESULTS Overall, mean age was 52.6 ± 12.8 years; 26 (25.5%) were female. Disease etiology was ischemic in 58, nonischemic in 36, and other in 8. Overall, 30-day, 6-month, and 1-year survival for the BTT patients was 95.1%, 83.5%, and 78.8%, respectively. The 6-month survival in 38 patients in the clinical trial (pre-FDA) was 88.8% and was not statistically significant compared with the 76.2% 6-month survival in the 64 patients in the post-FDA approval period (p value = 0.1). Major adverse events among the 102 BTT patients included right ventricular failure in 5 (4.9%), LVAD driveline infections in 25 (24.5%), neurologic events in 10 (9.8%), and gastrointestinal bleeding in 18 (17.6%) patients. In addition, 1 patient (0.98%) had pump thrombus requiring device replacement. CONCLUSIONS Despite significant morbidity, use of the HeartMate II LVAD as BTT provides excellent hemodynamic support and is associated with excellent survival and low mortality. In addition, there needs to be improvement and focused strategies in the areas of gastrointestinal bleeding, driveline infections, and adverse neurologic events for these devices to be able to provide a real long-term alternative to heart transplantation.
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McKelvie RS, Moe GW, Cheung A, Costigan J, Ducharme A, Estrella-Holder E, Ezekowitz JA, Floras J, Giannetti N, Grzeslo A, Harkness K, Heckman GA, Howlett JG, Kouz S, Leblanc K, Mann E, O'Meara E, Rajda M, Rao V, Simon J, Swiggum E, Zieroth S, Arnold JMO, Ashton T, D'Astous M, Dorian P, Haddad H, Isaac DL, Leblanc MH, Liu P, Sussex B, Ross HJ. The 2011 Canadian Cardiovascular Society Heart Failure Management Guidelines Update: Focus on Sleep Apnea, Renal Dysfunction, Mechanical Circulatory Support, and Palliative Care. Can J Cardiol 2011; 27:319-38. [DOI: 10.1016/j.cjca.2011.03.011] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 03/15/2011] [Indexed: 10/18/2022] Open
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Adamson RM, Dembitsky WP, Baradarian S, Chammas J, May-Newman K, Chillcott S, Stahovich M, McCalmont V, Ortiz K, Hoagland P, Jaski B. Aortic valve closure associated with HeartMate left ventricular device support: Technical considerations and long-term results. J Heart Lung Transplant 2011; 30:576-82. [DOI: 10.1016/j.healun.2010.11.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 11/14/2010] [Accepted: 11/29/2010] [Indexed: 10/18/2022] Open
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Abstract
The introduction of the heart lung machine more than 50 years ago proved in principle that heart function can be replaced, albeit for short periods. This was followed by attempts to produce total or partial artificial hearts that could function for prolonged periods of time. Progress in this field has been intermittent but has accelerated considerably in the past 10 years, with ventricular assist devices (VADs) reaching an impressive degree of sophistication and complexity owing to the contributions from clinicians, engineers, scientists, industrialists, and others. This review describes the currently available types of VADs, their current clinical use, the patient selection process, the trend toward use of VADs in patients with less severe heart failure, and the use of VADs for myocardial recovery in combination with novel pharmacological strategies, gene therapy, and cell therapy.
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Affiliation(s)
- Cesare M Terracciano
- Harefield Heart Science Centre, Imperial College London, Harefield, Middlesex UB9 6JH, UK
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22
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Carr CM, Jacob J, Park SJ, Karon BL, Williamson EE, Araoz PA. CT of Left Ventricular Assist Devices. Radiographics 2010; 30:429-44. [DOI: 10.1148/rg.302095734] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
The mortality of acute heart failure (AHF) remains high despite advances in treatment. Mechanical circulatory support (MCS) can be applied in AHF, refractory to conventional measures, to improve outcomes. This article aims to describe the current and the prospective role of MCS in the treatment of AHF. The support strategies and the indications of MCS are continuously evolving, including situations considered as contraindications in the past. Appropriate patient selection, advanced device technology and improved patient management have contributed to the substantially improved results. Evolution in device technology results in evolution of the clinical applications of MCS. Earlier application of MCS, with novel, flexible and individualized support strategies is now feasible. Bridging to recovery is the most intriguing support strategy and bridging to future treatments is feasible with long-term support. The progressively expanding role of MCS in the treatment of heart failure is not reflected in the existing guidelines. Being reserved for refractory heart failure, MCS has been applied to the sickest patients who were less amenable to randomization. This explains the lack of robust evidence, but also highlights the value of the progressively improving results. The anticipated wider application of MCS should be better defined, systematically recorded, and guided.
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Affiliation(s)
- Antonis A Pitsis
- Thessaloniki Heart Institute, St Luke's Hospital-Cardiac Surgery, Thessaloniki, Greece.
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Abstract
Patients increasingly require longer durations of left ventricular assist device (LVAD) therapy. Despite a recent trend toward continuous flow VADs, the HeartMate XVE is still commonly used, but its longevity remains a significant limitation. Existing surveillance methods of pump failure often give inconclusive results. XVE electrical current waveforms were collected regularly (2001-2008) and sorted into quartiles according to number of days until pump failure (Q1, 0-34; Q2, 34-160; Q3, 160-300; and Q4, 300-390 days). Thoratec waveform files were converted into text files. The 10-second electrical current, voltage waveform was identified and isolated for analysis. Waveforms were analyzed by principal component analysis (PCA) and with a fast Fourier transform. Quartiles were compared with analysis of variance (ANOVA). Waveforms (n = 454) were collected for 21 patients with failed pumps. An artificial neural network was used to predict pump failure within 30 days from the waveform characteristics identified though signal processing.
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HeartMate Left Ventricular Assist System Exchange: Results and Technical Considerations. ASAIO J 2009; 55:598-601. [DOI: 10.1097/mat.0b013e3181bd446a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Stewart GC, Brooks K, Pratibhu PP, Tsang SW, Semigran MJ, Smith CM, Saniuk C, Camuso JM, Fang JC, Mudge GH, Couper GS, Baughman KL, Stevenson LW. Thresholds of Physical Activity and Life Expectancy for Patients Considering Destination Ventricular Assist Devices. J Heart Lung Transplant 2009; 28:863-9. [DOI: 10.1016/j.healun.2009.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 05/09/2009] [Accepted: 05/09/2009] [Indexed: 10/20/2022] Open
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Pagani FD, Miller LW, Russell SD, Aaronson KD, John R, Boyle AJ, Conte JV, Bogaev RC, MacGillivray TE, Naka Y, Mancini D, Massey HT, Chen L, Klodell CT, Aranda JM, Moazami N, Ewald GA, Farrar DJ, Frazier OH. Extended mechanical circulatory support with a continuous-flow rotary left ventricular assist device. J Am Coll Cardiol 2009; 54:312-21. [PMID: 19608028 DOI: 10.1016/j.jacc.2009.03.055] [Citation(s) in RCA: 705] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 03/03/2009] [Accepted: 03/10/2009] [Indexed: 11/28/2022]
Abstract
OBJECTIVES This study sought to evaluate the use of a continuous-flow rotary left ventricular assist device (LVAD) as a bridge to heart transplantation. BACKGROUND LVAD therapy is an established treatment modality for patients with advanced heart failure. Pulsatile LVADs have limitations in design precluding their use for extended support. Continuous-flow rotary LVADs represent an innovative design with potential for small size and greater reliability by simplification of the pumping mechanism. METHODS In a prospective, multicenter study, 281 patients urgently listed (United Network of Organ Sharing status 1A or 1B) for heart transplantation underwent implantation of a continuous-flow LVAD. Survival and transplantation rates were assessed at 18 months. Patients were assessed for adverse events throughout the study and for quality of life, functional status, and organ function for 6 months. RESULTS Of 281 patients, 222 (79%) underwent transplantation, LVAD removal for cardiac recovery, or had ongoing LVAD support at 18-month follow-up. Actuarial survival on support was 72% (95% confidence interval: 65% to 79%) at 18 months. At 6 months, there were significant improvements in functional status and 6-min walk test (from 0% to 83% of patients in New York Heart Association functional class I or II and from 13% to 89% of patients completing a 6-min walk test) and in quality of life (mean values improved 41% with Minnesota Living With Heart Failure and 75% with Kansas City Cardiomyopathy questionnaires). Major adverse events included bleeding, stroke, right heart failure, and percutaneous lead infection. Pump thrombosis occurred in 4 patients. CONCLUSIONS A continuous-flow LVAD provides effective hemodynamic support for at least 18 months in patients awaiting transplantation, with improved functional status and quality of life. (Thoratec HeartMate II Left Ventricular Assist System [LVAS] for Bridge to Cardiac Transplantation; NCT00121472).
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Harrison M, Anyanwu A, Pinney SP. The management of stage D heart failure. THE MOUNT SINAI JOURNAL OF MEDICINE, NEW YORK 2009; 76:404-414. [PMID: 19642155 DOI: 10.1002/msj.20124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Abstract
Cardiac transplantation and mechanical circulatory support are possible options for improving survival and quality of life in patients with isolated cardiac disease and end-stage heart failure. Transplantation is limited by donor availability but has a median survival of 10 years. Post-transplant immunosuppression is often transplant center dependent, but a tacrolimus and mycophenolate mofetil-based regimen may be preferred. Sirolimus may reduce the progression rate of transplant vasculopathy. There has been a trend toward continuous-flow left ventricular assist devices because of their increased durability and reduced size. A variety of surgical and percutaneous ventricular assist devices may be used as a bridge to decision on a patient's candidacy for transplantation. Mechanical circulatory support as destination therapy has not been widely implemented because of poor device durability, but this is expected to change with newer devices. Mechanical circulatory support as a bridge to myocardial recovery has been successful only in a few patients.
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Affiliation(s)
- Andrew Boyle
- University of Minnesota, 420 SE Delaware Street, Minneapolis, MN 55455, USA.
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Ruiz Fernández M, González Pinto Á. Asistencia ventricular como indicación definitiva (terapia de destino) en la insuficiencia cardíaca avanzada. CIRUGIA CARDIOVASCULAR 2009. [DOI: 10.1016/s1134-0096(09)70161-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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Abstract
Optimal medical therapy may ameliorate acute cardiogenic shock and long-term congestive heart failure symptoms; however, in certain cases mechanical circulatory assistance may be helpful or even required. Different devices can be considered based on the anticipated duration of need and the acuity of the cardiovascular failure being treated. A working knowledge of balloon pumps and ventricular assist devices, their indications, function, and potential complications, allows the physician to provide optimal care for those patients presenting with such a device.
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Affiliation(s)
- Brian C Hiestand
- Department of Emergency Medicine, Ohio State University, Columbus, OH 43210, USA.
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Tang DG, Oyer PE, Mallidi HR. Ventricular Assist Devices: History, Patient Selection, and Timing of Therapy. J Cardiovasc Transl Res 2009; 2:159-67. [DOI: 10.1007/s12265-009-9098-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Accepted: 02/26/2009] [Indexed: 11/30/2022]
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Physiologic and pathologic changes in patients with continuous-flow ventricular assist devices. J Cardiovasc Transl Res 2009; 2:154-8. [PMID: 20559982 DOI: 10.1007/s12265-009-9092-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 02/12/2009] [Indexed: 01/28/2023]
Abstract
The clinical use of the newer continuous-flow pumps for mechanical circulatory support have resulted in superior outcomes including significantly reduced complication rates with improved durability over first generation pulsatile design pumps. However, as with all new technology, the newer LVADs have introduced a different set of management issues, as well as a unique risk profile into the mechanical circulatory support arena that were previously absent or unimportant with pulsatile LVADs. These include the effects of continuous flow on the systemic circulation and end-organ function, risk of thromboembolism, and pump thrombosis related to contact bearings in the blood path, the possible increased incidence of gastrointestinal bleeding, and ventricular arrhythmias, as well as alterations in the unloading characteristics of continuous-flow devices. This manuscript overviews the physiologic and pathologic effects that are associated with continuous-flow pumps and their unique management issues and complications.
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Pagani FD. Continuous-Flow Rotary Left Ventricular Assist Devices with “3rd Generation” Design. Semin Thorac Cardiovasc Surg 2008; 20:255-63. [DOI: 10.1053/j.semtcvs.2008.08.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2008] [Indexed: 11/11/2022]
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John R. Current Axial-Flow Devices—the HeartMate II and Jarvik 2000 Left Ventricular Assist Devices. Semin Thorac Cardiovasc Surg 2008; 20:264-72. [DOI: 10.1053/j.semtcvs.2008.08.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2008] [Indexed: 11/11/2022]
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von Bayern MP, Cadeiras M, Deng MC. Destination therapy: does progress depend on left ventricular assist device development? Heart Fail Clin 2007; 3:349-67. [PMID: 17723941 DOI: 10.1016/j.hfc.2007.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The role of therapy using mechanical circulatory support devices has evolved rapidly over the last two decades. New developments in the field achieved smaller adverse events, but, currently, only minor improvements in survival were observed in published observational data. The authors discuss the development of mechanical circulatory support devices as a "destination therapy" option for patients who have end-stage heart failure and are ineligible for heart transplantation as it relates to left ventricular assist device development.
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Abstract
BACKGROUND AND AIM OF THE STUDY Traditional left ventricular assist device (LVAD) implantation requires extensive dissection and use of cardiopulmonary bypass (CPB). Potential adverse effects of CPB in very ill end-stage heart failure patients include right ventricular dysfunction, end-organ injury, and bleeding. We sought to evaluate the feasibility and outcome of LVAD insertion without CPB. METHODS The Jarvik 2000 is an axial-flow pump newly involved in a phase I clinical trial in status I patients as a bridge to transplantation. Seven patients received this pump through thoracotomy or sternotomy with or without the use of CPB. RESULTS All patients had NYHA class IV heart failure with end-organ dysfunction requiring inotropic therapy. Two were in cardiogenic shock, necessitating full CPB support. Five patients had the Jarvik implanted off-CPB. The off-CPB patients were associated with decreased length of surgery, mechanical ventilation, blood transfusions, inotropic support, and hospital stay including rehabilitation. Nearly all of the patients had complete resolution of liver and kidney dysfunction. CONCLUSION We have demonstrated that off-CPB insertion of axial flow LVADs is feasible, safe, and potentially advantageous. Although we are encouraged by the perioperative simplicity of this strategy, we acknowledge that additional implants and comparisons of outcomes with traditional pulsatile and continuous flow device techniques will be necessary to advocate its widespread adoption.
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Affiliation(s)
- Craig H Selzman
- Division of Cardiothoracic Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7065, USA.
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Haft JW, Suzuki Y, Aaronson KD, Dyke DB, Wright S, Poirier VL, Pagani FD. Identification of Device Malfunction in Patients Supported With the HeartMate XVE Left Ventricular Assist System. ASAIO J 2007; 53:298-303. [PMID: 17515718 DOI: 10.1097/mat.0b013e318033a6b0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Predicting end-of-life for left ventricular assist devices is important to determine timing of device removal. A retrospective analysis was performed on 46 patients undergoing implantation of the latest HeartMate XVE from July 1, 2003, through March 31, 2006. Devices were assessed by analysis of motor current waveforms and quantification of the titanium or copper particles within dust localized to the driveline vent filter by optical, polarized light, scanning electron microscopy, and energy dispersive x-ray spectroscopy. Assessments were performed monthly for patients supported > or =330 days or for unexpected device alarms. Thirty-one (67%) patients were supported for <330 days and 15 (33%) were supported for > or =330 days. No malfunctions occurred in patients supported <330 days. For patients supported > or =330 days, five had abnormal current waveforms or copper and titanium dust localized to the vent filter. One underwent urgent transplantation, three underwent device replacement (one death; two ongoing), and one is with ongoing support. Of the remaining 10 patients, seven underwent transplantation; two remain on device; and one died while on left ventricular assist device support. There were no unexpected device failures. Bearing wear of the HeartMate XVE is predictable by analysis of current waveforms or titanium and copper dust within the vent filter.
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Affiliation(s)
- Jonathan W Haft
- Section of Cardiac Surgery, University of Michigan Health Systems, Ann Arbor, Michigan, USA
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Selzman CH. Invited commentary. Ann Thorac Surg 2006; 82:1418-9. [PMID: 16996945 DOI: 10.1016/j.athoracsur.2006.05.086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 05/19/2006] [Accepted: 05/26/2006] [Indexed: 11/26/2022]
Affiliation(s)
- Craig H Selzman
- Division of Cardiothoracic Surgery, University of North Carolina at Chapel Hill, 3040 Burnett Womack, CB #7065, Chapel Hill, NC 27599, USA.
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