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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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Meissner F, Galbas MC, Szvetics S, von Zur Mühlen C, Heidt T, Maier A, Bock M, Czerny M, Bothe W, Reiss S. Cardioaortic dimensions in German landrace pigs derived from cardiac magnetic resonance imaging. Sci Rep 2024; 14:1869. [PMID: 38253776 PMCID: PMC10803781 DOI: 10.1038/s41598-024-52376-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 01/17/2024] [Indexed: 01/24/2024] Open
Abstract
Pigs are frequently applied as animal models in cardiovascular research due to their anatomical and physiological similarity to humans. For study planning and refinement, precise knowledge of the cardioaortic dimensions is essential. In a retrospective single-center study, the cardioaortic dimensions and left ventricular function of German Landrace pigs were assessed using cardiac MRI. All parameters were compared between male and female pigs and analyzed for correlation with body weight. In total, 15 pigs were included (7 male and 8 female, weight 60.9 ± 7.0 kg). The left ventricle revealed an end-diastolic diameter of 50.5 ± 4.4 mm and an ejection fraction of 51.2 ± 9.8%. The diameters of the ascending and descending aorta were 21.3 ± 2.3 and 16.2 ± 1.4 mm, respectively. There were no significant differences between male and female pigs, except that males had a smaller end-diastolic left ventricular volume (p = 0.041). A moderate correlation was found between body weight and the aortic annulus diameter (R = 0.57, p = 0.027). In conclusion, cardiac MRI allows precise quantification of porcine cardioaortic dimensions. For medical device testing, size differences between pigs and humans should be considered.
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Affiliation(s)
- Florian Meissner
- Department of Cardiovascular Surgery, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany.
| | - Michelle Costa Galbas
- Department of Cardiovascular Surgery, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Sophie Szvetics
- Department of Cardiovascular Surgery, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Constantin von Zur Mühlen
- Department of Cardiology and Angiology, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Timo Heidt
- Department of Cardiology and Angiology, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Alexander Maier
- Department of Cardiology and Angiology, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Michael Bock
- Department of Diagnostic and Interventional Radiology, Medical Physics, Faculty of Medicine, University of Freiburg, Killianstrasse 5a, 79106, Freiburg, Germany
| | - Martin Czerny
- Department of Cardiovascular Surgery, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Wolfgang Bothe
- Department of Cardiovascular Surgery, University Heart Center Freiburg - Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Strasse 55, 79106, Freiburg, Germany
| | - Simon Reiss
- Department of Diagnostic and Interventional Radiology, Medical Physics, Faculty of Medicine, University of Freiburg, Killianstrasse 5a, 79106, Freiburg, Germany
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Zhu Y, Marin-Cuartas M, Park MH, Imbrie-Moore AM, Wilkerson RJ, Madira S, Mullis DM, Woo YJ. Ex vivo biomechanical analysis of the Ross procedure using the modified inclusion technique in a 3-dimensionally printed left heart simulator. J Thorac Cardiovasc Surg 2023; 165:e103-e116. [PMID: 34625236 PMCID: PMC8924018 DOI: 10.1016/j.jtcvs.2021.06.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 05/31/2021] [Accepted: 06/14/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The inclusion technique was developed to reinforce the pulmonary autograft to prevent dilation after the Ross procedure. Anticommissural plication (ACP), a modification technique, can reduce graft size and create neosinuses. The objective was to evaluate pulmonary valve biomechanics using the inclusion technique in the Ross procedure with and without ACP. METHODS Seven porcine and 5 human pulmonary autografts were harvested from hearts obtained from a meat abattoir and from heart transplant recipients and donors, respectively. Five additional porcine autografts without reinforcement were used as controls. The Ross procedure was performed using the inclusion technique with a straight polyethylene terephthalate graft. The same specimens were tested both with and without ACP. Hemodynamic parameter data, echocardiography, and high-speed videography were collected via the ex vivo heart simulator. RESULTS Porcine autograft regurgitation was significantly lower after the use of inclusion technique compared with controls (P < .01). ACP compared with non-ACP in both porcine and human pulmonary autografts was associated with lower leaflet rapid opening velocity (3.9 ± 2.4 cm/sec vs 5.9 ± 2.4 cm/sec; P = .03; 3.5 ± 0.9 cm/sec vs 4.4 ± 1.0 cm/sec; P = .01), rapid closing velocity (1.9 ± 1.6 cm/sec vs 3.1 ± 2.0 cm/sec; P = .01; 1.8 ± 0.7 cm/sec vs 2.2 ± 0.3 cm/sec; P = .13), relative rapid opening force (4.6 ± 3.0 vs 7.7 ± 5.2; P = .03; 3.0 ± 0.6 vs 4.0 ± 2.1; P = .30), and relative rapid closing force (2.5 ± 3.4 vs 5.9 ± 2.3; P = .17; 1.4 ± 1.3 vs 2.3 ± 0.6; P = .25). CONCLUSIONS The Ross procedure using the inclusion technique demonstrated excellent hemodynamic parameter results. The ACP technique was associated with more favorable leaflet biomechanics. In vivo validation should be performed to allow direct translation to clinical practice.
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Affiliation(s)
- Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif; Department of Bioengineering, Stanford University, Stanford, Calif
| | - Mateo Marin-Cuartas
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif; University Department of Cardiac Surgery, Leipzig Heart Center, Leipzig, Germany
| | - Matthew H Park
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif; Department of Mechanical Engineering, Stanford University, Stanford, Calif
| | - Annabel M Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif; Department of Mechanical Engineering, Stanford University, Stanford, Calif
| | - Robert J Wilkerson
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif
| | - Sarah Madira
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif
| | - Danielle M Mullis
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif
| | - Y Joseph Woo
- Department of Cardiothoracic Surgery, Stanford University, Stanford, Calif; Department of Bioengineering, Stanford University, Stanford, Calif.
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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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Zhu Y, Park MH, Imbrie-Moore A, Wilkerson R, Madira S, Woo YJ. Biomechanical evaluation of aortic regurgitation from cusp prolapse using an ex vivo 3D-printed commissure geometric alignment device. J Cardiothorac Surg 2022; 17:303. [PMID: 36496476 PMCID: PMC9737730 DOI: 10.1186/s13019-022-02049-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/27/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Aortic regurgitation (AR) is one of the most common cardiac valvular diseases, and it is frequently caused by cusp prolapse. However, the precise relationship of commissure position and aortic cusp prolapse with AR is not fully understood. In this study, we developed a 3D-printed commissure geometric alignment device to investigate the effect of commissure height and inter-commissure angle on AR and aortic cusp prolapse. METHODS Three porcine aortic valves were explanted from hearts obtained from a meat abattoir and were mounted in the commissure geometric alignment device. Nine commissure configurations were tested for each specimen, exploring independent and concurrent effects of commissure height and inter-commissure angle change on AR and aortic cusp prolapse. Each commissure configuration was tested in our 3D printed ex vivo left heart simulator. Hemodynamics data, echocardiography, and high-speed videography were obtained. RESULTS AR due to aortic cusp prolapse was successfully generated using our commissure geometric alignment device. Mean aortic regurgitation fraction measured for the baseline, high commissure, low commissure, high commissure and wide inter-commissure angle, high commissure and narrow inter-commissure angle, low commissure and wide inter-commissure angle, low commissure and narrow inter-commissure angle, wide commissure, and narrow commissure configurations from all samples were 4.6 ± 1.4%, 9.7 ± 3.7%, 4.2 ± 0.5%, 11.7 ± 5.8%, 13.0 ± 8.5%, 4.8 ± 0.9%, 7.3 ± 1.7%, 5.1 ± 1.2%, and 7.1 ± 3.1%, respectively. CONCLUSIONS AR was most prominent when commissure heights were changed from their native levels with concomitant reduced inter-commissure angle. Findings from this study provide important evidence demonstrating the relationship between commissure position and aortic cusp prolapse and may have a significant impact on patient outcomes after surgical repair of aortic valves.
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Affiliation(s)
- Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA
- Department of Bioengineering, Stanford University, Stanford, USA
| | - Matthew H Park
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA
- Department of Mechanical Engineering, Stanford University, Stanford, USA
| | - Annabel Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA
- Department of Mechanical Engineering, Stanford University, Stanford, USA
| | - Robert Wilkerson
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA
| | - Sarah Madira
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA
| | - Y Joseph Woo
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, 300 Pasteur Drive, Falk Cardiovascular Research Center, Stanford, CA, 94305, USA.
- Department of Bioengineering, Stanford University, Stanford, USA.
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Zhu Y, Imbrie-Moore AM, Paulsen MJ, Priromprintr B, Wang H, Lucian HJ, Farry JM, Woo YJ. Novel bicuspid aortic valve model with aortic regurgitation for hemodynamic status analysis using an ex vivo simulator. J Thorac Cardiovasc Surg 2022; 163:e161-e171. [PMID: 32747120 PMCID: PMC7769867 DOI: 10.1016/j.jtcvs.2020.06.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 02/03/2023]
Abstract
OBJECTIVE The objective was to design and evaluate a clinically relevant, novel ex vivo bicuspid aortic valve model that mimics the most common human phenotype with associated aortic regurgitation. METHODS Three bovine aortic valves were mounted asymmetrically in a previously validated 3-dimensional-printed left heart simulator. The non-right commissure and the non-left commissure were both shifted slightly toward the left-right commissure, and the left and right coronary cusps were sewn together. The left-right commissure was then detached and reimplanted 10 mm lower than its native height. Free margin shortening was used for valve repair. Hemodynamic status, high-speed videography, and echocardiography data were collected before and after the repair. RESULTS The bicuspid aortic valve model was successfully produced and repaired. High-speed videography confirmed prolapse of the fused cusp of the baseline bicuspid aortic valve models in diastole. Hemodynamic and pressure data confirmed accurate simulation of diseased conditions with aortic regurgitation and the subsequent repair. Regurgitant fraction postrepair was significantly reduced compared with that at baseline (14.5 ± 4.4% vs 28.6% ± 3.4%; P = .037). There was no change in peak velocity, peak gradient, or mean gradient across the valve pre- versus postrepair: 293.3 ± 18.3 cm/sec versus 325.3 ± 58.2 cm/sec (P = .29), 34.3 ± 4.2 mm Hg versus 43.3 ± 15.4 mm Hg (P = .30), and 11 ± 1 mm Hg versus 9.3 ± 2.5 mm Hg (P = .34), respectively. CONCLUSIONS An ex vivo bicuspid aortic valve model was designed that recapitulated the most common human phenotype with aortic regurgitation. These valves were successfully repaired, validating its potential for evaluating valve hemodynamics and optimizing surgical repair for bicuspid aortic valves.
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Affiliation(s)
- Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA,Department of Bioengineering, Stanford University, Stanford, CA
| | - Annabel M. Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA,Department of Mechanical Engineering, Stanford University, Stanford, CA
| | | | - Bryant Priromprintr
- Department of Pediatrics, Division of Pediatric Cardiology, Stanford University, Stanford, CA
| | - Hanjay Wang
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA
| | - Haley J. Lucian
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA
| | - Justin M. Farry
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA
| | - Y. Joseph Woo
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA,Department of Bioengineering, Stanford University, Stanford, CA
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Zhao Y, Li T, Wu M, Zeng Z, Gao M, Bao X, Xu Z, Zhou J, Feng J, Feng R, Jing Z. Simultaneous transcatheter treatment of ascending aortic aneurysm with aortic and mitral regurgitation: an in vitro study. Interact Cardiovasc Thorac Surg 2021; 33:474-482. [PMID: 34115874 DOI: 10.1093/icvts/ivab101] [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: 08/11/2020] [Revised: 12/22/2020] [Accepted: 02/18/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES We sought to explore the efficacy of the endovascular repair of an ascending aortic aneurysm with aortic and mitral regurgitation by 2 novel valved stents. METHODS We established models of ascending aortic aneurysms combined with aortic and mitral regurgitation in 10 pig hearts, then implanted self-expanding aortic fenestrated and mitral valved stents via the transapical approach. We applied a fluoroscopy-guided in vitro setting to test the approach, then analysed continuous circulating flushing at 37°C. Finally, we determined operating times, echocardiography and changes of coronary flow as well as fenestration alignment with the coronary ostia. RESULTS This approach resulted in a 100% overall technical success rate, excellent handling properties and precise positioning. The time taken to implant the 2 valved stents was 59 ± 12 min. Flow of the left and right coronary arteries did not significantly decrease after the stents were implanted (330.4 ± 12.06 ml/min vs 289.4 ± 5.29 ml/min, P < 0.001; 376.8 ± 10.5 ml/min vs 350.0 ± 14.5 ml/min; P < 0.001). We found no obvious regurgitation and perivalvular leakage; nor did the gradients of the aortic and mitral valves as well as of the left ventricular outflow tract increase significantly. The final angiographic examination and profile of the coronary opening confirmed the good position of the valved stents, the exclusion of the aneurysm and the patency of both coronary arteries. CONCLUSIONS These findings indicate the potential for combined transcatheter aortic root and mitral valve replacement in treating aortic root pathologies. In future, in vivo studies are expected to validate this approach and ascertain its durability.
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Affiliation(s)
- Yuxi Zhao
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Tao Li
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China.,Department of Cardiovascular Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Mingwei Wu
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Zhaoxiang Zeng
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Minxin Gao
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Xianhao Bao
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Ziyi Xu
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Jian Zhou
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Jiaxuan Feng
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Rui Feng
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
| | - Zaiping Jing
- Department of Vascular Surgery, Changhai Hospital, Endovascular Diagnosis and Treatment Center for Heart Valvular Diseases, and Endovascular Diagnosis and Treatment Center for Aortic Dissection, Navy Medical University, Shanghai, China
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Almanza M, Clavica F, Chavanne J, Moser D, Obrist D, Carrel T, Civet Y, Perriard Y. Feasibility of a Dielectric Elastomer Augmented Aorta. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2001974. [PMID: 33747718 PMCID: PMC7967089 DOI: 10.1002/advs.202001974] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/09/2020] [Indexed: 06/12/2023]
Abstract
Although heart transplantation is a gold standard for severe heart failure, there is a need for alternative effective therapies. A dielectric-elastomer aorta is used to augment the physiological role of the aorta in the human circulatory system. To this end, the authors developed a tubular dielectric elastomer actuator (DEA) able to assist the heart by easing the deformation of the aorta in the systole and by increasing its recoil force in the diastole. In vitro experiments using a pulsatile flow-loop, replicating human physiological flow and pressure conditions, show a reduction of 5.5% (47 mJ per cycle) of the heart energy with this device. Here, the controlled stiffness of the DEA graft, which is usually difficult to exploit for actuators, is perfectly matching the assistance principle. At the same time, the physiological aortic pressure is exploited to offer a prestretch to the DEA which otherwise would require an additional bulky pre-stretching system to reach high performances.
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Affiliation(s)
- Morgan Almanza
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
| | - Francesco Clavica
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
- ARTORG Center for Biomedical Engineering ResearchUniversity of BernBern3012Switzerland
| | - Jonathan Chavanne
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
| | - David Moser
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
| | - Dominik Obrist
- ARTORG Center for Biomedical Engineering ResearchUniversity of BernBern3012Switzerland
| | - Thierry Carrel
- Department of Cardiovascular SurgeryUniversity Hospital and University of BernBern3012Switzerland
| | - Yoan Civet
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
| | - Yves Perriard
- Integrated Actuators LaboratoryÉcole Polytechnique fédérale de Lausanne (EPFL)Neuchâtel2000Switzerland
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Paulsen MJ, Imbrie-Moore AM, Baiocchi M, Wang H, Hironaka CE, Lucian HJ, Farry JM, Thakore AD, Zhu Y, Ma M, MacArthur JW, Woo YJ. Comprehensive Ex Vivo Comparison of 5 Clinically Used Conduit Configurations for Valve-Sparing Aortic Root Replacement Using a 3-Dimensional-Printed Heart Simulator. Circulation 2020; 142:1361-1373. [PMID: 33017215 PMCID: PMC7531510 DOI: 10.1161/circulationaha.120.046612] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Supplemental Digital Content is available in the text. Background: Many graft configurations are clinically used for valve-sparing aortic root replacement, some specifically focused on recapitulating neosinus geometry. However, the specific impact of such neosinuses on valvular and root biomechanics and the potential influence on long-term durability are unknown. Methods: Using a custom 3-dimenstional–printed heart simulator with porcine aortic roots (n=5), the anticommissural plication, Stanford modification, straight graft (SG), Uni-Graft, and Valsalva graft configurations were tested in series using an incomplete counterbalanced measures design, with the native root as a control, to mitigate ordering effects. Hemodynamic and videometric data were analyzed using linear models with conduit as the fixed effect of interest and valve as a fixed nuisance effect with post hoc pairwise testing using Tukey’s correction. Results: Hemodynamics were clinically similar between grafts and control aortic roots. Regurgitant fraction varied between grafts, with SG and Uni-Graft groups having the lowest regurgitant fractions and anticommissural plication having the highest. Root distensibility was significantly lower in SG versus both control roots and all other grafts aside from the Stanford modification (P≤0.01 for each). All grafts except SG had significantly higher cusp opening velocities versus native roots (P<0.01 for each). Relative cusp opening forces were similar between SG, Uni-Graft, and control groups, whereas anticommissural plication, Stanford modification, and Valsalva grafts had significantly higher opening forces versus controls (P<0.01). Cusp closing velocities were similar between native roots and the SG group, and were significantly lower than observed in the other conduits (P≤0.01 for each). Only SG and Uni-Graft groups experienced relative cusp closing forces approaching that of the native root, whereas relative forces were >5-fold higher in the anticommissural plication, Stanford modification, and Valsalva graft groups. Conclusions: In this ex vivo modeling system, clinically used valve-sparing aortic root replacement conduit configurations have comparable hemodynamics but differ in biomechanical performance, with the straight graft most closely recapitulating native aortic root biomechanics.
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Affiliation(s)
- Michael J Paulsen
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Annabel M Imbrie-Moore
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA.,Department of Mechanical Engineering (A.M.I.M.), Stanford University, CA
| | - Michael Baiocchi
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA.,Department of Health Research and Policy (M.B.), Stanford University, CA
| | - Hanjay Wang
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Camille E Hironaka
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Haley J Lucian
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Justin M Farry
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Akshara D Thakore
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Yuanjia Zhu
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Michael Ma
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - John W MacArthur
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA
| | - Y Joseph Woo
- Department of Cardiothoracic Surgery (M.J.P., A.M.I.-M., M.B., H.W., C.E.H., H.J.L., J.M.F., A.D.T., Y.Z., M.M., J.W.M., Y.J.W.), Stanford University, CA.,Department of Bioengineering (Y.J.W.), Stanford University, CA
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10
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Zhu Y, Imbrie-Moore AM, Park MH, Paulsen MJ, Wang H, MacArthur JW, Woo YJ. Ex Vivo Analysis of a Porcine Bicuspid Aortic Valve and Aneurysm Disease Model. Ann Thorac Surg 2020; 111:e113-e115. [PMID: 32663472 DOI: 10.1016/j.athoracsur.2020.05.086] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 05/13/2020] [Indexed: 12/28/2022]
Abstract
We identified an extremely rare congenital porcine type 0 lateral bicuspid aortic valve from a fresh porcine heart. Using a 3-dimensionally printed ex vivo left heart simulator, we analyzed valvular hemodynamics at baseline, in an aortic aneurysm disease model, and after valve-sparing root replacement. We showed that bicuspid aortic valve regurgitation due to aortic aneurysm can be successfully repaired without significant hemodynamic impairment using the valve-sparing root replacement technique in an individualized approach. Our results provide direct hemodynamic evidence supporting the use of valve-sparing root replacement for patients with bicuspid aortic valve regurgitation.
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Affiliation(s)
- Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California; Department of Bioengineering, Stanford University, Stanford, California
| | - Annabel M Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California; Department of Mechanical Engineering, Stanford University, Stanford, California
| | - Matthew H Park
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California; Department of Mechanical Engineering, Stanford University, Stanford, California
| | - Michael J Paulsen
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Hanjay Wang
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - John W MacArthur
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Y Joseph Woo
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California; Department of Bioengineering, Stanford University, Stanford, California.
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11
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Ferrari E, Wang C, Berdajs D, von Segesser LK. Chimney grafts in renal arteries: a clinical model for coronary perfusion in future transcatheter aortic root repair techniques. J Cardiothorac Surg 2020; 15:132. [PMID: 32517779 PMCID: PMC7285528 DOI: 10.1186/s13019-020-01184-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 06/03/2020] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES Given the similarities between coronary ostia and renal arteries, chimney grafts (CG) for kidney perfusion during abdominal endovascular aneurysm repair (EVAR) can be considered for coronary perfusion in future transcatheter aortic root repair (TARR) techniques. We analysed the results of renal CG and compared anatomic and technical details with root and coronary anthropometric data. METHODS Current status of kidney perfusion with CG was reviewed from literature. Anatomic details, technical data, CG performance and clinical outcome were collected and analysed. Anatomic details of aortic landing zone and renal arteries were compared with human anthropometric data of aortic root, ascending aorta and coronary ostia. RESULTS Seventeen articles reported 430 patients (mean age:74.5 ± 2.9 years) treated with renal CG. Mean length and diameter of proximal landing zone were 2.0 ± 2.0 mm and 26.4 ± 4.3 mm, respectively (anthropometric correspondence: ascending aorta diameter of 29.3 mm). Aortic endograft mean diameter was 26.4 ± 7.3 mm with reported oversize of 19.5 ± 6.0%. In total, 590 renal arteries were treated (left:325; right:265; bilateral:139 cases). Mean left and right renal artery diameters were 5.7 ± 0.6 mm and 5.8 ± 0.7 mm, respectively (anthropometric correspondence: coronary ostia diameters of 4.8 mm (left) and 3.7 mm (right)) with reported CG oversize of 19.75 ± 6% (left) and 18.1 ± 5.1% (right). Mean follow-up time was 16.5 ± 8.5 months, CG occlusion rate was 3.2% and endoleak I or II was reported in 83 patients (19.3%), requiring 7 procedures. CONCLUSIONS CG provides satisfactory results in patients with suitable renal artery diameter. Based on aortic root and coronary anthropometric data, CG can be considered in future TARR technologies for coronary perfusion but further tests for flow evaluations are mandatory.
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Affiliation(s)
- Enrico Ferrari
- Cardiac Surgery, Cardiocentro Ticino, Via Tesserete 48, 6900, Lugano, Switzerland.
- Cardiovascular Surgery, University Hospital of Zurich, Zurich, Switzerland.
| | - Changtian Wang
- Cardiovascular Surgery, Nanjing Jinling Hospital, Nanjing, China
| | - Denis Berdajs
- Cardiovascular Surgery, University Hospital of Basel, Basel, Switzerland
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12
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A Novel Aortic Regurgitation Model from Cusp Prolapse with Hemodynamic Validation Using an Ex Vivo Left Heart Simulator. J Cardiovasc Transl Res 2020; 14:283-289. [PMID: 32495264 DOI: 10.1007/s12265-020-10038-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 05/20/2020] [Indexed: 02/07/2023]
Abstract
Although ex vivo simulation is a valuable tool for surgical optimization, a disease model that mimics human aortic regurgitation (AR) from cusp prolapse is needed to accurately examine valve biomechanics. To simulate AR, four porcine aortic valves were explanted, and the commissure between the two largest leaflets was detached and re-implanted 5 mm lower to induce cusp prolapse. Four additional valves were tested in their native state as controls. All valves were tested in a heart simulator while hemodynamics, high-speed videography, and echocardiography data were collected. Our AR model successfully reproduced cusp prolapse with significant increase in regurgitant volume compared with that of the controls (23.2 ± 8.9 versus 2.8 ± 1.6 ml, p = 0.017). Hemodynamics data confirmed the simulation of physiologic disease conditions. Echocardiography and color flow mapping demonstrated the presence of mild to moderate eccentric regurgitation in our AR model. This novel AR model has enormous potential in the evaluation of valve biomechanics and surgical repair techniques. Graphical Abstract.
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Ferrari E, Scoglio M, Piazza G, Maisano F, von Segesser LK, Berdajs D. Transcatheter aortic root replacement with chimney grafts for coronary perfusion: a preliminary test in a three-dimensional-printed root model. Interact Cardiovasc Thorac Surg 2020; 31:121-128. [DOI: 10.1093/icvts/ivaa056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/05/2020] [Accepted: 02/26/2020] [Indexed: 01/11/2023] Open
Abstract
Abstract
OBJECTIVES
Transcatheter aortic root repair is still not available because of the technical challenge of coronary perfusion. The use of chimney grafts for coronary ostia can be an option and we tested the flow-through coronary chimney grafts deployed in a 3-dimensional-printed root model as part of a transcatheter aortic root repair system.
METHODS
A 3-dimensional-printed root was used to test the coronary flow after the deployment of 1 root endograft (28 mm diameter) and two 6-mm diameter 10-cm long coronary chimney grafts. Continuous coronary flows were measured in a bench test at different pressure levels (60, 80 and 100 mmHg) and compared to target coronary flows (250 ml/min at rest for the left and 150 ml/min at rest for the right coronary artery).
RESULTS
The computed tomography scan-based root was modified with two 5-mm diameter coronary conduits to overcome the limits of the original 3-dimensional-printed coronary ostia. The root was placed in the hydrodynamic system: adjusted coronary free flow at 60, 80 and 100 mmHg of pressure was 1913, 2200 and 2480 ml/min for left coronary and 1633, 2026 and 2366 ml/min for right coronary, respectively. After endografts deployment, mean chimney graft flow at 60, 80 and 100 mmHg of pressure was 1053 ml/min (−45%), 1306 ml/min (−41%) and 1502 ml/min (−40%) for the left coronary and 1100 ml/min (−33%), 1460 ml/min (−28%) and 1626 ml/min (−31%) for the right coronary, respectively.
CONCLUSIONS
In this preliminary study, chimney grafts for transcatheter aortic root repair provided 830% of target flow in the right coronary (−31% of free flow) and 414% of target flow in the left coronary (−42% of free flow) which is more than sufficient for both coronaries in real-life conditions. The potential of this approach should be further explored with specifically designed endografts.
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Affiliation(s)
- Enrico Ferrari
- Cardiovascular Surgery Unit, Cardiocentro Ticino, Lugano, Switzerland
- Cardiovascular Surgery Unit, University Hospital of Zurich, Zurich, Switzerland
| | - Martin Scoglio
- Cardiovascular Research Unit, University Hospital of Lausanne, Lausanne, Switzerland
| | - Giulia Piazza
- Cardiovascular Research Unit, University Hospital of Lausanne, Lausanne, Switzerland
| | - Francesco Maisano
- Cardiovascular Surgery Unit, University Hospital of Zurich, Zurich, Switzerland
| | | | - Denis Berdajs
- Cardiovascular Surgery Unit, University Hospital of Basel, Basel, Switzerland
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14
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Suitability of 3D-Printed Root Models for the Development of Transcatheter Aortic Root Repair Technologies. ASAIO J 2019; 65:874-881. [DOI: 10.1097/mat.0000000000000903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Russo M, Werner P, Moscato F, Rath C, Stoiber M, Hengstenberg C, Andreas M. A novel, transfemoral prosthesis designed to treat aortic valve regurgitation: technical aspects and procedural guide. J Cardiovasc Med (Hagerstown) 2019; 20:844-848. [PMID: 31568090 DOI: 10.2459/jcm.0000000000000874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Marco Russo
- Division of Cardiac Surgery, Department of Surgery
| | - Paul Werner
- Division of Cardiac Surgery, Department of Surgery
| | | | | | | | - Christian Hengstenberg
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria
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Modeling conduit choice for valve-sparing aortic root replacement on biomechanics with a 3-dimensional–printed heart simulator. J Thorac Cardiovasc Surg 2019; 158:392-403. [DOI: 10.1016/j.jtcvs.2018.10.145] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 10/07/2018] [Accepted: 10/19/2018] [Indexed: 12/24/2022]
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