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Zhu Y, Wilkerson RJ, Pandya PK, Mullis DM, Wu CA, Madira S, Marin-Cuartas M, Park MH, Imbrie-Moore AM, Woo YJ. Biomechanical Engineering Analysis of Pulmonary Valve Leaflet Hemodynamics and Kinematics in the Ross Procedure. J Biomech Eng 2023; 145:011005. [PMID: 35864775 PMCID: PMC9445321 DOI: 10.1115/1.4055033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/25/2022] [Indexed: 11/08/2022]
Abstract
The Ross procedure using the inclusion technique with anticommissural plication (ACP) is associated with excellent valve hemodynamics and favorable leaflet kinematics. The objective was to evaluate individual pulmonary cusp's biomechanics and fluttering by including coronary flow in the Ross procedure using an ex vivo three-dimensional-printed heart simulator. Ten porcine and five human pulmonary autografts were harvested from a meat abattoir and heart transplant patients. Five porcine autografts without reinforcement served as controls. The other autografts were prepared using the inclusion technique with and without ACP (ACP and NACP). Hemodynamic and high-speed videography data were measured using the ex vivo heart simulator. Although porcine autografts showed similar leaflet rapid opening and closing mean velocities, human ACP compared to NACP autografts demonstrated lower leaflet rapid opening mean velocity in the right (p = 0.02) and left coronary cusps (p = 0.003). The porcine and human autograft leaflet rapid opening and closing mean velocities were similar in all three cusps. Porcine autografts showed similar leaflet flutter frequencies in the left (p = 0.3) and noncoronary cusps (p = 0.4), but porcine NACP autografts versus controls demonstrated higher leaflet flutter frequency in the right coronary cusp (p = 0.05). The human NACP versus ACP autografts showed higher flutter frequency in the noncoronary cusp (p = 0.02). The leaflet flutter amplitudes were similar in all three cusps in both porcine and human autografts. The ACP compared to NACP autografts in the Ross procedure was associated with more favorable leaflet kinematics. These results may translate to the improved long-term durability of the pulmonary autografts.
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Affiliation(s)
- Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304; Department of Bioengineering, Stanford University, Stanford, CA 94304
| | - Robert J. Wilkerson
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304
| | - Pearly K. Pandya
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304; Department of Mechanical Engineering, Stanford University, Stanford, CA 94304
| | - Danielle M. Mullis
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304
| | - Catherine A. Wu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304
| | - Sarah Madira
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304
| | - Mateo Marin-Cuartas
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304; University Department of Cardiac Surgery, Leipzig Heart Center, Leipzig 04289, Germany
| | - Matthew H. Park
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304; Department of Mechanical Engineering, Stanford University, Stanford, CA 94304
| | - Annabel M. Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94304; Department of Mechanical Engineering, Stanford University, Stanford, CA 94304
| | - Y. Joseph Woo
- Falk Cardiovascular Research Center Department of Cardiothoracic Surgery, Stanford University, MD 300 Pasteur Drive, Stanford, CA 94305; Department of Bioengineering, Stanford University, Stanford, CA 94304
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2
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Hatoum H, Ahn S, Lilly S, Maureira P, Crestanello J, Thourani VH, Dasi LP. Flow dynamics of surgical and transcatheter aortic valves: Past to present. JTCVS OPEN 2022; 9:43-56. [PMID: 36003460 PMCID: PMC9390780 DOI: 10.1016/j.xjon.2022.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 01/12/2022] [Indexed: 11/15/2022]
Affiliation(s)
- Hoda Hatoum
- Department of Biomedical Engineering, Michigan Technological University, Houghton, Mich
- Health Research Institute, Center of Biocomputing and Digital Health and Institute of Computing and Cybernetics, Michigan Technological University, Houghton, Mich
- Center of Biocomputing and Digital Health, Michigan Technological University, Houghton, Mich
- Address for reprints: Hoda Hatoum, PhD, Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Dr, Houghton, MI 49931.
| | - Sunyoung Ahn
- Department of Biomedical Engineering, Michigan Technological University, Houghton, Mich
| | - Scott Lilly
- Division of Cardiovascular Medicine, The Ohio State University, Columbus, Ohio
| | - Pablo Maureira
- Department of Cardiovascular Surgery, CHU de Nancy, Nancy, France
| | - Juan Crestanello
- Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minn
| | - Vinod H. Thourani
- Department of Cardiovascular Surgery, Marcus Valve Center, Piedmont Heart Institute, Atlanta, Ga
| | - Lakshmi Prasad Dasi
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
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3
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Pietrasanta L, Zheng S, De Marinis D, Hasler D, Obrist D. Characterization of Turbulent Flow Behind a Transcatheter Aortic Valve in Different Implantation Positions. Front Cardiovasc Med 2022; 8:804565. [PMID: 35097022 PMCID: PMC8794584 DOI: 10.3389/fcvm.2021.804565] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/14/2021] [Indexed: 11/21/2022] Open
Abstract
The development of turbulence after transcatheter aortic valve (TAV) implantation may have detrimental effects on the long-term performance and durability of the valves. The characterization of turbulent flow generated after TAV implantation can provide fundamental insights to enhance implantation techniques. A self-expandable TAV was tested in a pulse replicator and the three-dimensional flow field was extracted by means of tomographic particle image velocimetry. The valve was fixed inside a silicone phantom mimicking the aortic root and the flow field was studied for two different supra-annular axial positions at peak systole. Fluctuating velocities and turbulent kinetic energy were compared between the two implantations. Velocity spectra were derived at different spatial positions in the turbulent wakes to characterize the turbulent flow. The valve presented similar overall flow topology but approximately 8% higher turbulent intensity in the lower implantation. In this configuration, axial views of the valve revealed smaller opening area and more corrugated leaflets during systole, as well as more accentuated pinwheeling during diastole. The difference arose from a lower degree of expansion of the TAV's stent inside the aortic lumen. These results suggest that the degree of expansion of the TAV in-situ is related to the onset of turbulence and that a smaller and less regular opening area might introduce flow instabilities that could be detrimental for the long-term performance of the valve. The present study highlights how implantation mismatches may affect the structure and intensity of the turbulent flow in the aortic root.
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Affiliation(s)
- Leonardo Pietrasanta
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
- *Correspondence: Leonardo Pietrasanta
| | - Shaokai Zheng
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Dario De Marinis
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
- Dipartimento di Meccanica Matematica e Management, Centro di Eccellenza in Meccanica Computazionale, Politecnico di Bari, Bari, Italy
| | - David Hasler
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
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Werner P, Coti I, Kaider A, Gritsch J, Mach M, Kocher A, Laufer G, Andreas M. Long-term durability after surgical aortic valve replacement with the Trifecta and the Intuity valve-a comparative analysis. Eur J Cardiothorac Surg 2021; 61:416-424. [PMID: 34738111 DOI: 10.1093/ejcts/ezab470] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/08/2021] [Accepted: 09/23/2021] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Long-term durability of surgical bio-prostheses is a key factor, especially in the era of transcatheter aortic valve replacement. We compared the incidence of structural valve deterioration (SVD) between patients undergoing surgical aortic valve replacement (SAVR) with the Trifecta (Abbott Laboratories, Abbott Park, IL, USA) or the Intuity valve (Edwards Lifesciences, Irvine, CA, USA). METHODS Between April 2010 and May 2020, 1118 patients underwent SAVR with the Trifecta (n = 346) and the Intuity (n = 772) valve at a single centre. A total of 1070 patients (Trifecta n = 298, Intuity n = 772) were analysed after the exclusion of patients with pure regurgitation and endocarditis. Retro- and prospective echocardiographic and clinical follow-up was performed. Cox proportional hazards regression models were performed to identify prognostic factors for SVD, aortic re-interventions and mortality. RESULTS With 27 cases (Trifecta n = 23, Intuity n = 4) of SVD observed, cumulative incidence of SVD was significantly higher in the Trifecta cohort (P < 0.001). Implantation of a Trifecta valve [hazard ratio (HR) 11.20; 95% confidence interval 3.79-33.09], log-transformed preoperative creatinine (HR 2.47; 1.37-4.44) and sex (male HR 0.42; 0.19-0.92) emerged as prognostic factors of SVD. A significantly higher cumulative incidence of re-interventions was observed in the Trifecta cohort (P = 0.004) and valve type was an independent time-varying risk factor (HR at 12 months 2.78; 95% confidence interval 1.42-5.45). Overall, no significant differences in all-cause mortality were observed between the groups (log-rank test: P = 0.052). CONCLUSIONS SVD was significantly more frequent in patients receiving a Trifecta valve and its implantation was an independent risk factor for the occurrence of SVD and aortic valve re-interventions. This comparative analysis of 2 low-gradient bioprosthesis put the long-term durability of the Trifecta valve in question and need to be taken into consideration when performing bioprosthetic SAVR.
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Affiliation(s)
- Paul Werner
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Iuliana Coti
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Alexandra Kaider
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Jasmin Gritsch
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Markus Mach
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Alfred Kocher
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Guenther Laufer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Martin Andreas
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
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5
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Werner P, Gritsch J, Scherzer S, Gross C, Russo M, Coti I, Kocher A, Laufer G, Andreas M. Structural valve deterioration after aortic valve replacement with the Trifecta valve. Interact Cardiovasc Thorac Surg 2021; 32:39-46. [PMID: 33221889 DOI: 10.1093/icvts/ivaa236] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/24/2020] [Accepted: 09/16/2020] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Despite promising short- and mid-term results for durability of the Trifecta valve, contradictory reports of early structural valve deterioration (SVD) do exist. We investigated the incidence of SVD after surgical aortic valve replacement (SAVR) with the Trifecta in our single-centre experience. METHODS Data of 347 consecutive patients (mean age 71.6 ± 9.5 years, 63.4% male) undergoing SAVR with the Trifecta between 2011 and 2017 were analysed. Clinical and echocardiographic reports were obtained with a median follow-up of 41 months (1114 patient years). RESULTS Isolated SAVR was performed in 122 patients (35.2%), whereas 225 patients (64.8%) underwent concomitant procedures. The median EuroSCORE II was 4.0 (0.9; 7.1) and 30-day mortality was 3.7% (n = 13). Kaplan-Meier estimates for the freedom of overall mortality at 1, 5 and 7 years were 88.7 ± 1.7%, 73.7 ± 2.6% and 64.7 ± 4.2%, respectively. SVD was observed in 25 patients (7.2%) with a median time to first diagnosis of 73 months. Freedom of SVD was 92.5 ± 0.9% at 5 years and 65.5 ± 7.1% at 7 years. Thirteen patients underwent reintervention for SVD (6 re-SAVR, 7 valve-in-valve), resulting in a freedom of reintervention for the SVD of 98.5 ± 1.1% at 5 years and 76.9 ± 6.9% at 7 years. CONCLUSIONS We herein report one of the highest rates of SVD after SAVR with the Trifecta. These data indicate that the durability of the prosthesis decreases at intermediate to long-term follow-up, leading to considerable rates of reintervention due to SVD.
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Affiliation(s)
- Paul Werner
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Jasmin Gritsch
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Sabine Scherzer
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Christoph Gross
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Marco Russo
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Iuliana Coti
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Alfred Kocher
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Guenther Laufer
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Martin Andreas
- Division of Cardiac Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
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6
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Lee JH, Scotten LN, Hunt R, Caranasos TG, Vavalle JP, Griffith BE. Bioprosthetic aortic valve diameter and thickness are directly related to leaflet fluttering: Results from a combined experimental and computational modeling study. JTCVS OPEN 2021; 6:60-81. [PMID: 35211686 PMCID: PMC8864557 DOI: 10.1016/j.xjon.2020.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Bioprosthetic heart valves (BHVs) are commonly used in surgical and percutaneous valve replacement. The durability of percutaneous valve replacement is unknown, but surgical valves have been shown to require reintervention after 10 to 15 years. Further, smaller-diameter surgical BHVs generally experience higher rates of prosthesis-patient mismatch, which leads to higher rates of failure. Bioprosthetic aortic valves can flutter in systole, and fluttering is associated with fatigue and failure in flexible structures. The determinants of flutter in BHVs have not been well characterized, despite their potential to influence durability. METHODS We use an experimental pulse duplicator and a computational fluid-structure interaction model of this system to study the role of device geometry on BHV dynamics. The experimental system mimics physiological conditions, and the computational model enables precise control of leaflet biomechanics and flow conditions to isolate the effects of variations in BHV geometry on leaflet dynamics. RESULTS Both experimental and computational models demonstrate that smaller-diameter BHVs yield markedly higher leaflet fluttering frequencies across a range of conditions. The computational model also predicts that fluttering frequency is directly related to leaflet thickness. A scaling model is introduced that rationalizes these findings. CONCLUSIONS We systematically characterize the influence of BHV diameter and leaflet thickness on fluttering dynamics. Although this study does not determine how flutter influences device durability, increased flutter in smaller-diameter BHVs may explain how prosthesis-patient mismatch could induce BHV leaflet fatigue and failure. Ultimately, understanding the effects of device geometry on leaflet kinematics may lead to more durable valve replacements.
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Affiliation(s)
- Jae H Lee
- Department of Mathematics, University of North Carolina, Chapel Hill, NC
| | | | - Robert Hunt
- Department of Mathematics, University of North Carolina, Chapel Hill, NC
| | - Thomas G Caranasos
- Division of Cardiothoracic Surgery, Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC
| | - John P Vavalle
- Division of Cardiology, Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Boyce E Griffith
- Department of Mathematics, University of North Carolina, Chapel Hill, NC.,Computational Medicine Program and McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC
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7
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Johnson EL, Wu MCH, Xu F, Wiese NM, Rajanna MR, Herrema AJ, Ganapathysubramanian B, Hughes TJR, Sacks MS, Hsu MC. Thinner biological tissues induce leaflet flutter in aortic heart valve replacements. Proc Natl Acad Sci U S A 2020; 117:19007-19016. [PMID: 32709744 PMCID: PMC7431095 DOI: 10.1073/pnas.2002821117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Valvular heart disease has recently become an increasing public health concern due to the high prevalence of valve degeneration in aging populations. For patients with severely impacted aortic valves that require replacement, catheter-based bioprosthetic valve deployment offers a minimally invasive treatment option that eliminates many of the risks associated with surgical valve replacement. Although recent percutaneous device advancements have incorporated thinner, more flexible biological tissues to streamline safer deployment through catheters, the impact of such tissues in the complex, mechanically demanding, and highly dynamic valvular system remains poorly understood. The present work utilized a validated computational fluid-structure interaction approach to isolate the behavior of thinner, more compliant aortic valve tissues in a physiologically realistic system. This computational study identified and quantified significant leaflet flutter induced by the use of thinner tissues that initiated blood flow disturbances and oscillatory leaflet strains. The aortic flow and valvular dynamics associated with these thinner valvular tissues have not been previously identified and provide essential information that can significantly advance fundamental knowledge about the cardiac system and support future medical device innovation. Considering the risks associated with such observed flutter phenomena, including blood damage and accelerated leaflet deterioration, this study demonstrates the potentially serious impact of introducing thinner, more flexible tissues into the cardiac system.
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Affiliation(s)
- Emily L Johnson
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | - Michael C H Wu
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | - Fei Xu
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | - Nelson M Wiese
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | - Manoj R Rajanna
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | - Austin J Herrema
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011
| | | | - Thomas J R Hughes
- Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712;
| | - Michael S Sacks
- Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712;
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712
| | - Ming-Chen Hsu
- Department of Mechanical Engineering, Iowa State University, Ames, IA 50011;
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8
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Marx P, Kowalczyk W, Demircioglu A, Shehada SE, Wendta H, Mourad F, Thielmann M, Jakob H, Wendt D. An in vitro comparison of flow dynamics of the Magna Ease and the Trifecta prostheses. MINIM INVASIV THER 2019; 29:78-85. [PMID: 30888240 DOI: 10.1080/13645706.2019.1586732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Philipp Marx
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Wojciech Kowalczyk
- Chair of Mechanics and Robotics, University Duisburg-Essen, Duisburg, Germany
| | - Aydin Demircioglu
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
| | - Sharaf-Eldin Shehada
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Hermann Wendta
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Fanar Mourad
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Matthias Thielmann
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Heinz Jakob
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
| | - Daniel Wendt
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Hospital Essen, Essen, Germany
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9
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Rahmani B, McGregor C, Byrne G, Burriesci G. A Durable Porcine Pericardial Surgical Bioprosthetic Heart Valve: a Proof of Concept. J Cardiovasc Transl Res 2019; 12:331-337. [PMID: 30756359 PMCID: PMC6707964 DOI: 10.1007/s12265-019-09868-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 01/22/2019] [Indexed: 11/28/2022]
Abstract
Bioprosthetic leaflets made from animal tissues are used in the majority of surgical and transcatheter cardiac valve replacements. This study develops a new surgical bioprosthesis, using porcine pericardial leaflets. Porcine pericardium was obtained from genetically engineered pigs with a mutation in the GGTA-1 gene (GTKO) and fixed in 0.6% glutaraldehyde, and used to develop a new surgical valve design. The valves underwent in vitro hydrodynamic test in a pulse duplicator and high-cycled accelerated wear testing and were evaluated for acute haemodynamics and thrombogenicity in a juvenile sheep implant study for 48 h. The porcine surgical pericardial heart valves (pSPHVs) exhibited excellent hydrodynamics and reached 200 million cycles of in vitro durability, with no observable damage. Juvenile sheep implants demonstrated normal valve function with no acute thrombogenic response for either material. The pSPHV incorporates a minimalistic construction method using a tissue-to-tissue design to cover the stent. This new design is a proof of concept alternative to the use of bovine pericardium and synthetic fabric in surgical bioprosthetic heart valves.
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Affiliation(s)
- Benyamin Rahmani
- Cardiovascular Engineering Laboratory, UCL Mechanical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
| | - Christopher McGregor
- Institute of Cardiovascular Science, University College London, London, UK.,Department of Surgery, University of Alabama, Birmingham, AL, USA
| | - Guerard Byrne
- Institute of Cardiovascular Science, University College London, London, UK.,Department of Surgery, University of Alabama, Birmingham, AL, USA
| | - Gaetano Burriesci
- Cardiovascular Engineering Laboratory, UCL Mechanical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.,Ri.MED Foundation, Bioengineering Group, Palermo, Italy
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10
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Abstract
In this Editor's Review, articles published in 2017 are organized by category and summarized. We provide a brief reflection of the research and progress in artificial organs intended to advance and better human life while providing insight for continued application of these technologies and methods. Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level." Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. Peer-reviewed Special Issues this year included contributions from the 12th International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion edited by Dr. Akif Undar, Artificial Oxygen Carriers edited by Drs. Akira Kawaguchi and Jan Simoni, the 24th Congress of the International Society for Mechanical Circulatory Support edited by Dr. Toru Masuzawa, Challenges in the Field of Biomedical Devices: A Multidisciplinary Perspective edited by Dr. Vincenzo Piemonte and colleagues and Functional Electrical Stimulation edited by Dr. Winfried Mayr and colleagues. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide meaningful suggestions to the author's work whether eventually accepted or rejected. Without these excellent and dedicated reviewers the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, John Wiley & Sons for their expert attention and support in the production and marketing of Artificial Organs. We look forward to reporting further advances in the coming years.
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11
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Bozkurt S, Preston-Maher GL, Torii R, Burriesci G. Design, Analysis and Testing of a Novel Mitral Valve for Transcatheter Implantation. Ann Biomed Eng 2017; 45:1852-1864. [PMID: 28374279 PMCID: PMC5527080 DOI: 10.1007/s10439-017-1828-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 03/25/2017] [Indexed: 12/31/2022]
Abstract
Mitral regurgitation is a common mitral valve dysfunction which may lead to heart failure. Because of the rapid aging of the population, conventional surgical repair and replacement of the pathological valve are often unsuitable for about half of symptomatic patients, who are judged high-risk. Transcatheter valve implantation could represent an effective solution. However, currently available aortic valve devices are inapt for the mitral position. This paper presents the design, development and hydrodynamic assessment of a novel bi-leaflet mitral valve suitable for transcatheter implantation. The device consists of two leaflets and a sealing component made from bovine pericardium, supported by a self-expanding wireframe made from superelastic NiTi alloy. A parametric design procedure based on numerical simulations was implemented to identify design parameters providing acceptable stress levels and maximum coaptation area for the leaflets. The wireframe was designed to host the leaflets and was optimised numerically to minimise the stresses for crimping in an 8 mm sheath for percutaneous delivery. Prototypes were built and their hydrodynamic performances were tested on a cardiac pulse duplicator, in compliance with the ISO5840-3:2013 standard. The numerical results and hydrodynamic tests show the feasibility of the device to be adopted as a transcatheter valve implant for treating mitral regurgitation.
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Affiliation(s)
- Selim Bozkurt
- UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, London, WC1E 7JE, UK
| | - Georgia L Preston-Maher
- UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, London, WC1E 7JE, UK
| | - Ryo Torii
- UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, London, WC1E 7JE, UK
| | - Gaetano Burriesci
- UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, London, WC1E 7JE, UK. .,Ri.MED Foundation, Bioengineering Group, Palermo, Italy.
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