1
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Jahren SE, Martinez T, Walter A, Clavica F, Heinisch PP, Buffle E, Luedi MM, Hörer J, Obrist D, Carrel T, Civet Y, Perriard Y. Novel para-aortic cardiac assistance using a pre-stretched dielectric elastomer actuator. INTERDISCIPLINARY CARDIOVASCULAR AND THORACIC SURGERY 2024; 38:ivae027. [PMID: 38419585 PMCID: PMC10955250 DOI: 10.1093/icvts/ivae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/07/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024]
Abstract
OBJECTIVES We propose an evolution of a dielectric elastomer actuator-based cardiac assist device that acts as a counterpulsation system. We introduce a new pre-stretched actuator and implant the device in a graft bypass between the ascending and descending aorta to redirect all blood through the device (ascending aorta clamped). The objective was to evaluate the influence of these changes on the assistance provided to the heart. METHODS The novel para-aortic device and the new implantation technique were tested in vivo in 5 pigs. We monitored the pressure and flow in the aorta as well as the pressure-volume characteristics of the left ventricle. Different activation timings were tested to identify the optimal device actuation. RESULTS The proposed device helps reducing the end-diastolic pressure in the aorta by up to 13 ± 4.0% as well as the peak systolic pressure by up to 16 ± 3.6%. The early diastolic pressure was also increased up to 10 ± 3.5%. With different activation, we also showed that the device could increase or decrease the stroke volume. CONCLUSIONS The new setup and the novel para-aortic device presented here helped improve cardiac assistance compared to previous studies. Moreover, we revealed a new way to assist the heart by actuating the device at different starting time to modify the left ventricular stroke volume and stroke work.
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Affiliation(s)
- Silje Ekroll Jahren
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Thomas Martinez
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Armando Walter
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Francesco Clavica
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Paul Philipp Heinisch
- Department of Congenital and Pediatric Heart Surgery, German Heart Center Munich, Technical University of Munich, Munich, Germany
- Division of Congenital and Pediatric Heart Surgery, University Hospital of Munich, Ludwig-Maximilians-University, Munich, Germany
| | - Eric Buffle
- Department of Cardiology, Bern University Hospital Inselspital, University of Bern, Bern, Switzerland
| | - Markus Martin Luedi
- Department of Anaesthesiology, Bern University Hospital Inselspital, University of Bern, Bern, Switzerland
| | - Jürgen Hörer
- Department of Congenital and Pediatric Heart Surgery, German Heart Center Munich, Technical University of Munich, Munich, Germany
- Division of Congenital and Pediatric Heart Surgery, University Hospital of Munich, Ludwig-Maximilians-University, Munich, Germany
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Thierry Carrel
- Department of Cardiac Surgery, University of Zurich, Zurich, Switzerland
| | - Yoan Civet
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Yves Perriard
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
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2
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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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3
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Martinez T, Jahren SE, Walter A, Chavanne J, Clavica F, Ferrari L, Heinisch PP, Casoni D, Haeberlin A, Luedi MM, Obrist D, Carrel T, Civet Y, Perriard Y. A novel soft cardiac assist device based on a dielectric elastomer augmented aorta: An in vivo study. Bioeng Transl Med 2023; 8:e10396. [PMID: 36925677 PMCID: PMC10013878 DOI: 10.1002/btm2.10396] [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: 04/27/2022] [Revised: 07/12/2022] [Accepted: 08/08/2022] [Indexed: 11/05/2022] Open
Abstract
Although heart transplant is the preferred solution for patients suffering from heart failures, cardiac assist devices remain key substitute therapies. Among them, aortic augmentation using dielectric elastomer actuators (DEAs) might be an alternative technological application for the future. The electrically driven actuator does not require bulky pneumatic elements (such as conventional intra-aortic balloon pumps) and conforms tightly to the aorta thanks to the manufacturing method presented here. In this study, the proposed DEA-based device replaces a section of the aorta and acts as a counterpulsation device. The feasibility and validation of in vivo implantation of the device into the descending aorta in a porcine model, and the level of support provided to the heart are investigated. Additionally, the influence of the activation profile and delay compared to the start of systole is studied. We demonstrate that an activation of the DEA just before the start of systole (30 ms at 100 bpm) and deactivation just after the start of diastole (0-30 ms) leads to an optimal assistance of the heart with a maximum energy provided by the DEA. The end-diastolic and left ventricular pressures were lowered by up to 5% and 1%, respectively, compared to baseline. The early diastolic pressure was augmented in average by up to 2%.
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Affiliation(s)
- Thomas Martinez
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland
| | - Silje Ekroll Jahren
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland.,ARTORG Center for Biomedical Engineering Research University of Bern Bern Switzerland
| | - Armando Walter
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland
| | - Jonathan Chavanne
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland
| | - Francesco Clavica
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland.,ARTORG Center for Biomedical Engineering Research University of Bern Bern Switzerland
| | - Lorenzo Ferrari
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland.,ARTORG Center for Biomedical Engineering Research University of Bern Bern Switzerland
| | - Paul Philipp Heinisch
- Department of Congenital and Pediatric Heart Surgery, German Heart Center Munich Technical University of Munich Munich Germany.,Division of Congenital and Pediatric Heart Surgery University Hospital of Munich, Ludwig-Maximilians-University Munich Germany
| | - Daniela Casoni
- Experimental Surgery Facility University of Bern Bern Switzerland
| | - Andreas Haeberlin
- Department of Cardiology, Bern University Hospital Inselspital University of Bern Bern Switzerland
| | - Markus M Luedi
- Department of Anaesthesiology, Bern University Hospital Inselspital University of Bern Bern Switzerland
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering Research University of Bern Bern Switzerland
| | - Thierry Carrel
- Department of Cardiac Surgery University of Zurich Zurich Switzerland
| | - Yoan Civet
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland
| | - Yves Perriard
- Integrated Actuators Laboratory (LAI), École polytechnique fédérale de Lausanne (EPFL) Neuchâtel Switzerland
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4
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Romanova AN, Pugovkin AA, Telyshev DV. Studies of the Hemocompatibility of the Sputnik Ventricular Assist Device in Constant and Pulse-Modulated Operating Modes. BIOMEDICAL ENGINEERING 2022. [DOI: 10.1007/s10527-022-10214-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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5
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Khedr A, Mahmoud EE, Attallah N, Mir M, Boike S, Rauf I, Jama AB, Mushtaq H, Surani S, Khan SA. Role of octreotide in small bowel bleeding. World J Clin Cases 2022; 10:9192-9206. [PMID: 36159407 PMCID: PMC9477697 DOI: 10.12998/wjcc.v10.i26.9192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/30/2022] [Accepted: 08/15/2022] [Indexed: 02/05/2023] Open
Abstract
Gastrointestinal bleeding accounts for a drastic negative impact on the quality of the patients’ lives as it requires multiple diagnostic and therapeutic interventions to identify the source of the bleeding. Small bowel bleeding is the least common cause of gastrointestinal bleeding. However, it is responsible for the majority of complaints from patients with persisting or recurring bleeding where the primary source of bleeding cannot be identified despite investigation. A somatostatin analog known as octreotide is among the medical treatment modalities currently used to manage small bowel bleeding. This medication helps control symptoms of gastrointestinal bleeding by augmenting platelet aggregation, decreasing splanchnic blood flow, and antagonizing angiogenesis. In this review article, we will highlight the clinical efficacy of octreotide in small bowel bleeding and its subsequent effect on morbidity and mortality.
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Affiliation(s)
- Anwar Khedr
- Department of Internal Medicine, BronxCare Health System, Bronx, NY 10457, United States
| | | | - Noura Attallah
- Critical Care Medicine, Mayo Clinic Health System, Mankato, MN 56001, United States
| | - Mikael Mir
- Department of Medicine, University of Minnesota, Minneapolis, MN 55455, United States
| | - Sydney Boike
- Department of Medicine, University of Minnesota, Minneapolis, MN 55455, United States
| | - Ibtisam Rauf
- Department of Medicine, St. George School of Medicine, Grenada, West Indies
| | - Abbas B Jama
- Critical Care Medicine, Mayo Clinic Health System, Mankato, MN 56001, United States
| | - Hisham Mushtaq
- Critical Care Medicine, Mayo Clinic Health System, Mankato, MN 56001, United States
| | - Salim Surani
- Department of Medicine, Texas A&M University Health Science Center, Bryan, TX 77807, United States
| | - Syed A Khan
- Critical Care Medicine, Mayo Clinic Health System, Mankato, MN 56001, United States
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6
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Magkoutas K, Arm P, Meboldt M, Schmid Daners M. Physiologic Data-Driven Iterative Learning Control for Left Ventricular Assist Devices. Front Cardiovasc Med 2022; 9:922387. [PMID: 35911509 PMCID: PMC9326058 DOI: 10.3389/fcvm.2022.922387] [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: 04/17/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Continuous flow ventricular assist devices (cfVADs) constitute a viable and increasingly used therapy for end-stage heart failure patients. However, they are still operating at a fixed-speed mode that precludes physiological cfVAD response and it is often related to adverse events of cfVAD therapy. To ameliorate this, various physiological controllers have been proposed, however, the majority of these controllers do not account for the lack of pulsatility in the cfVAD operation, which is supposed to be beneficial for the physiological function of the cardiovascular system. In this study, we present a physiological data-driven iterative learning controller (PDD-ILC) that accurately tracks predefined pump flow trajectories, aiming to achieve physiological, pulsatile, and treatment-driven response of cfVADs. The controller has been extensively tested in an in-silico environment under various physiological conditions, and compared with a physiologic pump flow proportional-integral-derivative controller (PF-PIDC) developed in this study as well as the constant speed (CS) control that is the current state of the art in clinical practice. Additionally, two treatment objectives were investigated to achieve pulsatility maximization and left ventricular stroke work (LVSW) minimization by implementing copulsation and counterpulsation pump modes, respectively. Under all experimental conditions, the PDD-ILC as well as the PF-PIDC demonstrated highly accurate tracking of the reference pump flow trajectories, outperforming existing model-based iterative learning control approaches. Additionally, the developed controllers achieved the predefined treatment objectives and resulted in improved hemodynamics and preload sensitivities compared to the CS support.
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Affiliation(s)
| | | | | | - Marianne Schmid Daners
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
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7
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Efficacy of Pulsatile Flow Perfusion in Adult Cardiac Surgery: Hemodynamic Energy and Vascular Reactivity. J Clin Med 2021; 10:jcm10245934. [PMID: 34945230 PMCID: PMC8703987 DOI: 10.3390/jcm10245934] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 12/08/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
Background: The role of pulsatile (PP) versus non-pulsatile (NP) flow during a cardiopulmonary bypass (CPB) is still debated. This study’s aim was to analyze hemodynamic effects, endothelial reactivity and erythrocytes response during a CPB with PP or NP. Methods: Fifty-two patients undergoing an aortic valve replacement were prospectively randomized for surgery with either PP or NP flow. Pulsatility was evaluated in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE). Systemic (SVRi) and pulmonary (PVRi) vascular resistances, endothelial markers levels and erythrocyte nitric-oxide synthase (eNOS) activity were collected at different perioperative time-points. Results: In the PP group, the resultant EEP was 7.3% higher than the mean arterial pressure (MAP), which corresponded to 5150 ± 2291 ergs/cm3 of SHE. In the NP group, the EEP and MAP were equal; no SHE was produced. The PP group showed lower SVRi during clamp-time (p = 0.06) and lower PVRi after protamine administration and during first postoperative hours (p = 0.02). Lower SVRi required a higher dosage of norepinephrine in the PP group (p = 0.02). Erythrocyte eNOS activity results were higher in the PP patients (p = 0.04). Renal function was better preserved in the PP group (p = 0.001), whereas other perioperative variables were comparable between the groups. Conclusions: A PP flow during a CPB results in significantly lower SVRi, PVRi and increased eNOS production. The clinical impact of increased perioperative vasopressor requirements in the PP group deserves further evaluation.
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8
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Quintana-Villamandos B, Barranco M, Fernández I, Ruiz M, Del Cañizo JF. New Advances in Monitoring Cardiac Output in Circulatory Mechanical Assistance Devices. A Validation Study in a Porcine Model. Front Physiol 2021; 12:634779. [PMID: 33746776 PMCID: PMC7969803 DOI: 10.3389/fphys.2021.634779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/11/2021] [Indexed: 01/04/2023] Open
Abstract
Cardiac output (CO) measurement by continuous pulmonary artery thermodilution (COCTD) has been studied in patients with pulsatile-flow LVADs (left ventricular assist devices), confirming the clinical utility. However, it has not been validated in patients with continuous-flow LVADs. Therefore, the aim of this study was to assess the validity of COCTD in continuous-flow LVADs. Continuous-flow LVADs were implanted in six miniature pigs for partial assistance of the left ventricle. Both methods of measuring CO—measurement by COCTD and intermittent pulmonary artery thermodilution, standard technique (COITD)—were used in four consecutive moments of the study: before starting the LVAD (basal moment), and with the LVAD started in normovolemia, hypervolemia (fluid overloading), and hypovolemia (shock hemorrhage). At the basal moment, COCTD and COITD were closely correlated (r2 = 0.97), with a mean bias of −0.13 ± 0.16 L/min and percentage error of 11%. After 15 min of partial support LVAD, COCTD and COITD were closely correlated (r2 = 0.91), with a mean bias of 0.31 ± 0.35 L/min and percentage error of 20%. After inducing hypervolemia, COCTD and COITD were closely correlated (r2 = 0.99), with a mean bias of 0.04 ± 0.07 L/min and percentage error of 5%. After inducing hypovolemia, COCTD and COITD were closely correlated (r2 = 0.74), with a mean bias of 0.08 ± 0.22 L/min and percentage error of 19%. This study shows that continuous pulmonary thermodilution could be an alternative method of monitoring CO in a porcine model with a continuous-flow LVAD.
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Affiliation(s)
- Begoña Quintana-Villamandos
- Department of Anesthesiology and Intensive Care, Gregorio Marañón Hospital, Madrid, Spain.,Department of Pharmacology and Toxicology, Faculty of Medicine, Universidad Complutense, Madrid, Spain
| | - Mónica Barranco
- Department of Anesthesiology and Intensive Care, Gregorio Marañón Hospital, Madrid, Spain
| | - Ignacio Fernández
- Department of Anesthesiology and Intensive Care, Gregorio Marañón Hospital, Madrid, Spain
| | - Manuel Ruiz
- Department of Cardiovascular Surgery, Gregorio Marañón Hospital, Madrid, Spain.,Department of Surgery, Faculty of Medicine, Universidad Complutense, Madrid, Spain
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9
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Cordeiro TD, Sousa DL, Cestari IA, Lima AM. A physiological control system for ECG-synchronized pulsatile pediatric ventricular assist devices. Biomed Signal Process Control 2020. [DOI: 10.1016/j.bspc.2019.101752] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Ahsan I, Faraz A, Mehmood A, Ullah W, Ghani AR. Clinical Approach to Manage Gastrointestinal Bleeding with a Left Ventricular Assist Device (LVAD). Cureus 2019; 11:e6341. [PMID: 31938629 PMCID: PMC6952049 DOI: 10.7759/cureus.6341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Left ventricular assist devices (LVADs) are an exceedingly important form of mechanical support for patients with end-stage heart failure. LVADs can be utilized both as a bridge to cardiac transplant and also as a definitive treatment. However, a few complications are associated with LVAD placement, the most common and cumbersome of which is gastrointestinal (GI) bleeding with an incidence of about 30%. These bleeding events often require transfusion therapy, but they are rarely fatal. The etiologies of GI bleeding following LVAD are multifactorial and include unstable hemodynamics, an acquired von Willebrand factor (vWf) deficiency, impaired platelet aggregation, and activation of fibrinolytic systems. The treatment of choice in LVAD implantation-associated GI bleeding is endoscopy, which plays a vital role in both its diagnosis and management. Even so, its effectiveness in controlling post-LVAD implantation GI bleeding is still poorly ascertained. In this article, we will review the use of medication and alterations in the LVAD setting to prevent the occurrence of GI bleeding, as well as the findings of previously reported literature on LVAD implantation-associated GI bleeding.
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Affiliation(s)
- Irfan Ahsan
- Internal Medicine, Geisinger Health System, Danville, USA
| | - Aniqa Faraz
- Internal Medicine, University of Buffalo, Buffalo, USA
| | - Asif Mehmood
- Internal Medicine, Geisinger Medical Center, Danville, USA
| | - Waqas Ullah
- Internal Medicine, Abington Hospital - Jefferson Health, Abington, USA
| | - Ali R Ghani
- Cardiovascular Medicine, Saint Louis University, Saint Louis, USA
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11
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Yazdchi F, Rajab TK, Rinewalt D, Loberman D, Shekar P, Percy E, Hirji S, Urban R, Lehman RR, Mallidi HR, Singh SK. Comparison of heart transplant outcomes between recipients with pulsatile‐ vs continuous‐flow LVAD. J Card Surg 2019; 34:1062-1068. [DOI: 10.1111/jocs.14210] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Farhang Yazdchi
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Taufiek Konrad Rajab
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Daniel Rinewalt
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Dan Loberman
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Prem Shekar
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Edward Percy
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Sameer Hirji
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Read Urban
- Research DepartmentUnited Network for Organ Sharing Richmond Virginia
| | - Rebecca R. Lehman
- Research DepartmentUnited Network for Organ Sharing Richmond Virginia
| | - Hari R. Mallidi
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
| | - Steve K. Singh
- Division of Cardiac Surgery, Department of Surgery, Brigham and Women's HospitalHarvard Medical School Boston Massachusetts
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12
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Gastrointestinal Bleeding With Left Ventricular Assist Devices (LVAD): Locating the Leak and Identifying Outcomes. J Clin Gastroenterol 2019; 53:e202-e207. [PMID: 29688916 DOI: 10.1097/mcg.0000000000001041] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND GOALS Gastrointestinal bleeding (GIB) is a significant complication following left ventricular assist device (LVAD) implantation. We evaluated the incidence, predictors, endoscopic findings, and outcomes of GIB in LVAD recipients. STUDY Retrospective review of 205 adult patients undergoing HeartMate II LVAD implantation from January 2012 to June 2016. Patients were reviewed and separated into GIB (n=57; 28%) and non-GIB (n=148; 72%) groups. RESULTS Median time to GIB was 55 (range, 3 to 730) days. The GIB group patients were older (61±12 vs. 56±13, P=0.0042), more often underwent concomitant tricuspid valve (TV) repair (16% vs. 4%, P=0.007), and a higher percentage were assigned for destination therapy (75% vs. 55%, P=0.01). Angioectasia (33%) was the most common identified cause of GIB. Median time to endoscopic intervention was 1 day. The total number of hospital readmissions after LVAD was higher in the GIB group (median of 5 vs. 3, P=0.001), as was the total number of blood products transfused after LVAD (29 vs. 13, P≤0.0001). GIB was associated with an increased risk of death (hazard ratio, 1.94; 95% confidence interval, 1.16-3.25; P=0.01) and the mortality rate during hospitalization for GIB was 11% (P=0.0004). Receiving a heart transplant was associated with a decreased hazard of death (hazard ratio, 0.40; 95% confidence interval, 0.19-0.85; P=0.016). CONCLUSIONS Older age and destination therapy as implant strategy were found to be associated with an increased risk of GIB, consistent with previous studies. A unique finding in our study is the association of TV repair with a higher incidence of GIB. Further studies are needed to investigate possible mechanisms by which TV repair increases the incidence of GIB.
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13
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Granegger M, Dave H, Knirsch W, Thamsen B, Schweiger M, Hübler M. A Valveless Pulsatile Pump for the Treatment of Heart Failure with Preserved Ejection Fraction: A Simulation Study. Cardiovasc Eng Technol 2018; 10:69-79. [PMID: 30536212 DOI: 10.1007/s13239-018-00398-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 12/03/2018] [Indexed: 12/13/2022]
Abstract
PURPOSE Effective treatment of patients with terminal heart failure and preserved ejection fraction (HFpEF) is an unmet medical need. The aim of this study was to investigate a novel valveless pulsatile pump as a therapeutic option for the HFpEF population through comprehensive in silico investigations. METHODS The pump was simulated in a numerical model of the cardiovascular system of four HFpEF phenotypes and compared to a typical case of heart failure with reduced ejection fraction (HFrEF). The proposed pump, which was modeled as being directly connected to the left ventricle, features a single valveless inlet and outlet cannula and is driven in co-pulsation with the left ventricle. We collected hemodynamics for two different pump volumes (30 and 60 mL). RESULTS In all HFpEF conditions, the 30 mL pump improved the cardiac output by approximately 1 L/min, increased the mean arterial pressure by > 11% and lowered the mean left atrial pressure by > 30%. With the larger (60 mL) stroke volume, these hemodynamic improvements were more pronounced. In the HFrEF condition however, these effects were three times less in magnitude. CONCLUSIONS In this simulation study, the valveless pulsatile device improves hemodynamics in HFpEF patients by increasing the total stroke volume. The hemodynamic benefits are achieved with a small device volume comparable to implantable rotary blood pumps.
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Affiliation(s)
- Marcus Granegger
- Pediatric Cardiovascular Surgery, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland. .,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.
| | - Hitendu Dave
- Pediatric Cardiovascular Surgery, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Walter Knirsch
- Pediatric Cardiology, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Bente Thamsen
- Pediatric Cardiovascular Surgery, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Martin Schweiger
- Pediatric Cardiovascular Surgery, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Michael Hübler
- Pediatric Cardiovascular Surgery, Department of Surgery, Pediatric Heart Center, University Children's Hospital Zurich, Zurich, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
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14
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Chen Z, Jena SK, Giridharan GA, Sobieski MA, Koenig SC, Slaughter MS, Griffith BP, Wu ZJ. Shear stress and blood trauma under constant and pulse-modulated speed CF-VAD operations: CFD analysis of the HVAD. Med Biol Eng Comput 2018; 57:807-818. [PMID: 30406881 DOI: 10.1007/s11517-018-1922-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/24/2018] [Indexed: 11/30/2022]
Abstract
Modulation of pump speed has been proposed and implemented clinically to improve vascular pulsatility in continuous flow ventricular assist device patient. The flow dynamics of the HVAD with a promising asynchronous pump speed modulation and its potential risk for device-induced blood trauma was investigated numerically. The boundary conditions at the pump inlet and outlet were defined using the pressure waveforms adapted from the experimentally recorded ventricular and arterial pressure waveforms in a large animal ischemic heart failure (IHF) model supported by the HVAD operated at constant and modulated pump speeds. Shear stress fields and hemolysis indices were derived from the simulated flow fields. The overall features of the computationally generated flow waveforms at simulated constant and pulse-modulated speed operations matched with those of the experimentally recorded flow waveforms. The simulations showed that the shear stress field and hemolysis index vary throughout the cardiac cycle under the constant speed operation, and also as a function of modulation profile under modulated speed operation. The computational model did not demonstrate any differences in the time average hemolysis index between constant and modulated pump speed operations, thereby predicting pulse-modulated speed operation may help to restore vascular pulsatility without any further increased risk of blood trauma. Graphical abstract The streamline inside the HVAD pump and the wall shear stress distribution on the impeller surface at six discrete time instants over one cardiac cycle under constant speed operation (3000 rpm) (a) and under pulse-modulated speed operation (b). c Computationally predicted flow rate waveform under pulse-modulated speed operation. d Computationally predicted time-varying HI generated by the HVAD pump under the two operation modes constant speed (dash line) and pulse-modulated speed (solid line). These figures indicate that the pulse-modulated speed operation may help to restore vascular pulsatility without any further increased risk of blood trauma.
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Affiliation(s)
- Zengsheng Chen
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF 434A, Baltimore, MD, 21201, USA
| | - Sofen K Jena
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Guruprasad A Giridharan
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA.,Department of Bioengineering, Speed School of Engineering, University of Louisville, Louisville, KY, 40292, USA
| | - Michael A Sobieski
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Steven C Koenig
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA.,Department of Bioengineering, Speed School of Engineering, University of Louisville, Louisville, KY, 40292, USA
| | - Mark S Slaughter
- Department of Cardiovascular and Thoracic Surgery, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Bartley P Griffith
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF 434A, Baltimore, MD, 21201, USA
| | - Zhongjun J Wu
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, 10 South Pine Street, MSTF 434A, Baltimore, MD, 21201, USA. .,Fischell Department of Bioengineering, A. James Clark School of Engineering, University of Maryland, College Park, MD, 20742, USA.
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15
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The Physiological Rationale for Incorporating Pulsatility in Continuous-Flow Left Ventricular Assist Devices. Cardiol Rev 2018; 26:294-301. [DOI: 10.1097/crd.0000000000000202] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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16
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Raignault A, Bolduc V, Lesage F, Thorin E. Pulse pressure-dependent cerebrovascular eNOS regulation in mice. J Cereb Blood Flow Metab 2017; 37:413-424. [PMID: 26823473 PMCID: PMC5381440 DOI: 10.1177/0271678x16629155] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Arterial blood pressure is oscillatory; whether pulse pressure (PP) regulates cerebral artery myogenic tone (MT) and endothelial function is currently unknown. To test the impact of PP on MT and dilation to flow (FMD) or to acetylcholine (Ach), isolated pressurized mouse posterior cerebral arteries were subjected to either static pressure (SP) or a physiological PP (amplitude: 30 mm Hg; frequency: 550 bpm). Under PP, MT was significantly higher than in SP conditions ( p < 0.05) and was not affected by eNOS inhibition. In contrast, under SP, eNOS inhibition increased ( p < 0.05) MT to levels observed under PP, suggesting that PP may inhibit eNOS. At a shear stress of 20 dyn/cm2, FMD was lower ( p < 0.05) under SP than PP. Under SP, eNOS-dependent [Formula: see text] production contributed to FMD, while under PP, eNOS-dependent NO was responsible for FMD, indicating that PP favours eNOS coupling. Differences in FMD between pressure conditions were abolished after NOX2 inhibition. In contrast to FMD, Ach-induced dilations were higher ( p < 0.05) under SP than PP. Reactive oxygen species scavenging reduced ( p < 0.05) Ach-dependent dilations under SP, but increased ( p < 0.05) them under PP; hence, under PP, Ach promotes ROS production and limits eNOS-derived NO activity. In conclusion, PP finely regulates eNOS, controlling cerebral artery reactivity.
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Affiliation(s)
- Adeline Raignault
- 1 Faculty of Medicine, Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada.,2 Montreal Heart Institute Research Center, Montreal, Quebec, Canada
| | - Virginie Bolduc
- 1 Faculty of Medicine, Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada.,2 Montreal Heart Institute Research Center, Montreal, Quebec, Canada
| | - Frédéric Lesage
- 2 Montreal Heart Institute Research Center, Montreal, Quebec, Canada.,3 Ecole Polytechnique de Montréal, Montreal, Quebec, Canada
| | - Eric Thorin
- 1 Faculty of Medicine, Department of Pharmacology, Université de Montréal, Montreal, Quebec, Canada.,2 Montreal Heart Institute Research Center, Montreal, Quebec, Canada.,4 Faculty of Medicine, Department of Surgery, Université de Montréal, Montreal, Quebec, Canada
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17
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Gastrointestinal Bleeding Following LVAD Placement from Top to Bottom. Dig Dis Sci 2016; 61:1440-7. [PMID: 27017225 PMCID: PMC4875872 DOI: 10.1007/s10620-016-4123-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/06/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Left ventricular assist devices (LVADs) are an increasingly prevalent form of mechanical support for patients with end-stage heart failure. These devices can be implanted both as a bridge to transplant and as definitive/destination therapy. Gastrointestinal (GI) bleeding is one of the most common and recalcitrant long-term complications following LVAD implantation, with an incidence approaching 30 %. AIMS This review will discuss what is known about the pathophysiology of GI bleeding in LVADs and the currently available options for medical and/or endoscopic management. RESULTS The pathophysiology of bleeding is multifactorial, with hemodynamic alterations, acquired von Willebrand factor deficiency, and coagulopathy being most often implicated. The majority of bleeding events in this population result from angioectasias and gastroduodenal erosive disease. While these bleeding events are significant and often require transfusion therapy, they are rarely life threatening. Endoscopy remains the standard of care with upper endoscopy offering the highest diagnostic yield in these patients. However, the effectiveness of endoscopic hemostasis in this population is not well established. A small number of studies have evaluated medical therapy and alterations in LVAD settings as a means of preventing or treating bleeding with variable results. CONCLUSIONS In summary, GI bleeding with LVADs is a common occurrence and will continue to be as more LVADs are being performed for destination therapy.
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18
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Amornsawadwattana S, Nassif M, Raymer D, LaRue S, Chen CH. Video capsule endoscopy in left ventricular assist device recipients with obscure gastrointestinal bleeding. World J Gastroenterol 2016; 22:4559-4566. [PMID: 27182165 PMCID: PMC4858637 DOI: 10.3748/wjg.v22.i18.4559] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 02/17/2016] [Accepted: 03/14/2016] [Indexed: 02/06/2023] Open
Abstract
AIM: To assess whether video capsule endoscopy (VCE) affects the outcomes of left ventricular assist devices (LVADs) recipients with gastrointestinal bleeding.
METHODS: This is a retrospective study of LVAD recipients with obscure gastrointestinal bleeding (OGIB) who underwent VCE at a tertiary medical center between 2005 and 2013. All patients were admitted and monitored with telemetry and all VCE and subsequent endoscopic procedures were performed as inpatients. A VCE study was considered positive only when P2 lesions were found and was regarded as negative if P1 or P0 were identified. All patients were followed until heart transplant, death, or the end of the study.
RESULTS: Between 2005 and 2013, 30 patients with LVAD underwent VCE. Completion rate of VCE was 93.3% and there was no capsule retention. No interference of VCE recording or the function of LVAD was found. VCE was positive in 40% of patients (n = 12). The most common finding was active small intestinal bleeding (50%) and small intestinal angiodysplasia (33.3%). There was no difference in the rate of recurrent bleeding between patients with positive and negative VCE study (50.0% vs 55.6%, P = 1.00) during an average of 11.6 ± 9.6 mo follow up. Among patients with positive VCE, the recurrent bleeding rate did not differ whether subsequent endoscopy was performed (50% vs 50%, P = 1.00).
CONCLUSION: VCE can be safely performed in LVAD recipients with a diagnostic yield of 40%. VCE does not affect recurrent bleeding in LVAD patients regardless of findings.
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19
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Thorin-Trescases N, Thorin E. Lifelong Cyclic Mechanical Strain Promotes Large Elastic Artery Stiffening: Increased Pulse Pressure and Old Age-Related Organ Failure. Can J Cardiol 2015; 32:624-33. [PMID: 26961664 DOI: 10.1016/j.cjca.2015.12.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/02/2015] [Accepted: 12/14/2015] [Indexed: 01/08/2023] Open
Abstract
The arterial wall is under a huge mechanical constraint imposed by the cardiac cycle that is bound to generate damage with time. Each heartbeat indeed imposes a pulsatile pressure that generates a vascular stretch. Lifetime accumulation of pulsatile stretches will eventually induce fatigue of the elastic large arterial walls, such as aortic and carotid artery walls, promoting their stiffening that will gradually perturb the normal blood flow and local pressure within the organs, and lead to organ failure. The augmented pulse pressure induced by arterial stiffening favours left ventricular hypertrophy because of the repeated extra work against stiff high-pressure arteries, and tissue damage as a result of excessive pulsatile pressure transmitted into the microcirculation, especially in low resistance/high-flow organs such as the brain and kidneys. Vascular aging is therefore characterized by the stiffening of large elastic arteries leading to a gradual increase in pulse pressure with age. In this review we focus on the effect of age-related stiffening of large elastic arteries. We report the clinical evidence linking arterial stiffness and organ failure and discuss the molecular pathways that are activated by the increase of mechanical stress in the wall. We also discuss the possible interventions that could limit arterial stiffening with age, such as regular aerobic exercise training, and some pharmacological approaches.
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Affiliation(s)
| | - Eric Thorin
- Montreal Heart Institute, Research Center, Montreal, Quebéc, Canada; Department of Surgery, Faculty of Medicine, Université de Montréal, Montreal, Quebéc, Canada.
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20
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Chen Z, Mondal NK, Ding J, Gao J, Griffith BP, Wu ZJ. Shear-induced platelet receptor shedding by non-physiological high shear stress with short exposure time: glycoprotein Ibα and glycoprotein VI. Thromb Res 2015; 135:692-8. [PMID: 25677981 DOI: 10.1016/j.thromres.2015.01.030] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 01/01/2015] [Accepted: 01/30/2015] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The structural integrity of platelet receptors is essential for platelets to function normally in hemostasis and thrombosis in response to physiological and pathological stimuli. The aim of this study was to examine the shedding of two key platelet receptors, glycoprotein (GP) Ibα and GPVI, after exposed to the non-physiological high shear stress environment which commonly exists in blood contacting medical devices and stenotic blood vessels. MATERIALS AND METHODS In this in vitro experiment, we exposed healthy donor blood in our specially designed blood shearing device to three high shear stress levels (150, 225, 300 Pa) in combination with two short exposure time conditions (0.05 and 0.5 sec.). The expression and shedding of platelet GPIbα and GPVI receptors in the sheared blood samples were characterized using flow cytometry. The ability of platelet aggregation induced by ristocetin and collagen related to GPIbα and GPVI in the sheared blood samples, respectively, was evaluated by aggregometry. RESULTS AND CONCLUSIONS Compared to the normal blood, the surface expression of platelet GPIbα and GPVI in the sheared blood significantly decreased with increasing shear stress and exposure time. Moreover, the platelet aggregation induced by ristocetin and collagen reduced remarkably in a similar fashion. In summary non-physiological high shear stresses with short exposure time can induce shedding of platelet GPIbα and GPVI receptors, which may lead platelet dysfunction and influence the coagulation system. This study may provide a mechanistic insight into the platelet dysfunction and associated bleeding complication in patients supported by certain blood contacting medical devices.
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Affiliation(s)
- Zengsheng Chen
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Nandan K Mondal
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Jun Ding
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Mechanical Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Jingya Gao
- Department of Chemistry and Biochemistry, School of Science, Siena College, Loudonville, NY 12211, USA
| | - Bartley P Griffith
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Zhongjun J Wu
- Artificial Organs Laboratory, Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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21
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Hasin T, Matsuzawa Y, Guddeti RR, Aoki T, Kwon TG, Schettle S, Lennon RJ, Chokka RG, Lerman A, Kushwaha SS. Attenuation in peripheral endothelial function after continuous flow left ventricular assist device therapy is associated with cardiovascular adverse events. Circ J 2015; 79:770-7. [PMID: 25739569 DOI: 10.1253/circj.cj-14-1079] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Patients with heart failure (HF) have abnormal endothelial function. Although use of a continuous flow left ventricular assist device (CF-LVAD) results in significant hemodynamic improvement, the effects on systemic endothelial function are unclear. METHODS AND RESULTS Eighteen HF patients with CF-LVAD implantation were included in this prospective observational study. We measured reactive hyperemia index (RHI) before and after CF-LVAD implantation to evaluate sequential changes in endothelial function. Patients were followed clinically for the occurrence of adverse cardiovascular events, a composite of death, thrombosis, bleeding, HF, renal failure, and arrhythmia. Preoperative RHI was 1.77±0.39. Early in the postoperative period (7-14 days after operation) RHI significantly decreased to 1.19±0.31 (P<0.001, compared with preoperative RHI). At first and second follow-up (4-6 weeks and 3-7 months after operation) RHI remained lower at 1.48±0.50 (P=0.030) and 1.26±0.37 (P=0.002), respectively, compared with preoperative RHI. The decrease in early postoperative RHI relative to preoperative RHI was significantly associated with adverse cardiovascular events after CF-LVAD (age-adjusted risk ratio for 0.25 decrease in RHI, 1.35; 95% confidence interval: 1.13-1.62, P=0.001). CONCLUSIONS Peripheral endothelial function had a significant and persistent decline up to 5 months following implantation of CF-LVAD, and this decline was associated with adverse cardiovascular events. These findings may provide insight into some of the vascular complications following CF-LVAD in HF patients.
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Affiliation(s)
- Tal Hasin
- Division of Cardiovascular Disease, Mayo College of Medicine
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22
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Octreotide for the Management of Gastrointestinal Bleeding in a Patient with a HeartWare Left Ventricular Assist Device. Case Rep Cardiol 2014; 2014:826453. [PMID: 25587457 PMCID: PMC4281453 DOI: 10.1155/2014/826453] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 12/01/2014] [Indexed: 12/11/2022] Open
Abstract
HeartWare is a third generation left ventricular assist device (LVAD), widely used for the management of advanced heart failure patients. These devices are frequently associated with a significant risk of gastrointestinal (GI) bleeding. The data for the management of patients with LVAD presenting with GI bleeding is limited. We describe a 56-year-old lady, recipient of a HeartWare device, who experienced recurrent GI bleeding and was successfully managed with subcutaneous (SC) formulations of octreotide.
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23
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Gastric antral vascular ectasia: a rare manifestation for gastrointestinal bleeding in left ventricular assist device patients--an initial report. Dig Dis Sci 2014; 59:2826-30. [PMID: 24821465 DOI: 10.1007/s10620-014-3200-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 04/30/2014] [Indexed: 12/14/2022]
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24
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Halbreiner MS, Cruz V, Starling R, Soltesz E, Smedira N, Moravec C, Moazami N. Myocardial recovery: a focus on the impact of left ventricular assist devices. Expert Rev Cardiovasc Ther 2014; 12:589-600. [DOI: 10.1586/14779072.2014.909729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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25
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Milano AD, Dodonov M, Van Oeveren W, Onorati F, Gu YJ, Tessari M, Menon T, Gottin L, Faggian G. Pulsatile cardiopulmonary bypass and renal function in elderly patients undergoing aortic valve surgery†. Eur J Cardiothorac Surg 2014; 47:291-8; discussion 298. [DOI: 10.1093/ejcts/ezu136] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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26
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Wang TS, Hernandez AF, Felker GM, Milano CA, Rogers JG, Patel CB. Valvular Heart Disease in Patients Supported With Left Ventricular Assist Devices. Circ Heart Fail 2014; 7:215-22. [DOI: 10.1161/circheartfailure.113.000473] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Teresa S. Wang
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
| | - Adrian F. Hernandez
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
| | - G. Michael Felker
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
| | - Carmelo A. Milano
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
| | - Joseph G. Rogers
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
| | - Chetan B. Patel
- From the School of Medicine (T.S.W.), Division of Cardiology (A.F.H., G.M.F., J.G.R., C.B.P.), and Division of Cardiothoracic Surgery (C.A.M.), Duke University Medical Center, Durham, NC
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