Journal articles: 'Heart valve modeling'

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Fallahiarezoudar, Ehsan, Mohaddeseh Ahmadipourroudposht, and Noordin Mohd Yusof. "Geometric Modeling of Aortic Heart Valve." Procedia Manufacturing 2 (2015): 135–40. http://dx.doi.org/10.1016/j.promfg.2015.07.024.

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Zhu, Amadeus S., and K. Jane Grande-Allen. "Heart valve tissue engineering for valve replacement and disease modeling." Current Opinion in Biomedical Engineering 5 (March 2018): 35–41. http://dx.doi.org/10.1016/j.cobme.2017.12.006.

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Pasta, Salvatore, and Caterina Gandolfo. "Pre-Operative Modeling of Transcatheter Mitral Valve Replacement in a Surgical Heart Valve Bioprosthesis." Prosthesis 2, no. 1 (March 20, 2020): 39–45. http://dx.doi.org/10.3390/prosthesis2010004.

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Obstruction of the left ventricular outflow tract (LVOT) is a common complication of transcatheter mitral valve replacement (TMVR). This procedure can determine an elongation of an LVOT (namely, the neo-LVOT), ultimately portending hemodynamic impairment and patient death. This study aimed to understand the biomechanical implications of LVOT obstruction in a patient who underwent TMVR using a transcatheter heart valve (THV) to repair a failed bioprosthetic heart valve. We first reconstructed the heart anatomy and the bioprosthetic heart valve to virtually implant a computer-aided-design (CAD) model of THV and evaluate the neo-LVOT area. A numerical simulation of THV deployment was then developed to assess the anchorage of the THV to the bioprosthetic heart valve as well as the resulting Von Mises stress at the mitral annulus and the contract pressure among implanted bioprostheses. Quantification of neo-LVOT and THV deployment may facilitate more accurate predictions of the LVOT obstruction in TMVR and help clinicians in the optimal choice of the THV size.

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Earl, Emily, and Hadi Mohammadi. "Improving finite element results in modeling heart valve mechanics." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 232, no. 7 (June 7, 2018): 718–25. http://dx.doi.org/10.1177/0954411918780150.

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Finite element analysis is a well-established computational tool which can be used for the analysis of soft tissue mechanics. Due to the structural complexity of the leaflet tissue of the heart valve, the currently available finite element models do not adequately represent the leaflet tissue. A method of addressing this issue is to implement computationally expensive finite element models, characterized by precise constitutive models including high-order and high-density mesh techniques. In this study, we introduce a novel numerical technique that enhances the results obtained from coarse mesh finite element models to provide accuracy comparable to that of fine mesh finite element models while maintaining a relatively low computational cost. Introduced in this study is a method by which the computational expense required to solve linear and nonlinear constitutive models, commonly used in heart valve mechanics simulations, is reduced while continuing to account for large and infinitesimal deformations. This continuum model is developed based on the least square algorithm procedure coupled with the finite difference method adhering to the assumption that the components of the strain tensor are available at all nodes of the finite element mesh model. The suggested numerical technique is easy to implement, practically efficient, and requires less computational time compared to currently available commercial finite element packages such as ANSYS and/or ABAQUS.

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Ahmed, N. U. "Mathematical problems in modeling artificial heart." Mathematical Problems in Engineering 1, no. 3 (1995): 245–54. http://dx.doi.org/10.1155/s1024123x95000159.

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In this paper we discuss some problems arising in mathematical modeling of artificial hearts. The hydrodynamics of blood flow in an artificial heart chamber is governed by the Navier-Stokes equation, coupled with an equation of hyperbolic type subject to moving boundary conditions. The flow is induced by the motion of a diaphragm (membrane) inside the heart chamber attached to a part of the boundary and driven by a compressor (pusher plate). On one side of the diaphragm is the blood and on the other side is the compressor fluid. For a complete mathematical model it is necessary to write the equation of motion of the diaphragm and all the dynamic couplings that exist between its position, velocity and the blood flow in the heart chamber. This gives rise to a system of coupled nonlinear partial differential equations; the Navier-Stokes equation being of parabolic type and the equation for the membrane being of hyperbolic type. The system is completed by introducing all the necessary static and dynamic boundary conditions. The ultimate objective is to control the flow pattern so as to minimize hemolysis (damage to red blood cells) by optimal choice of geometry, and by optimal control of the membrane for a given geometry. The other clinical problems, such as compatibility of the material used in the construction of the heart chamber, and the membrane, are not considered in this paper. Also the dynamics of the valve is not considered here, though it is also an important element in the overall design of an artificial heart. We hope to model the valve dynamics in later paper.

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Zhong, Qi, Wen Hua Zeng, Xiao Yang Huang, and Bo Liang Wang. "Numerical Simulation of the Dynamics of Heart Valves: A Literature Review." Applied Mechanics and Materials 444-445 (October 2013): 1211–17. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.1211.

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Imaging techniques allow the visualization of the heart valves, but do not yields any information regarding the load applied to the heart valve information that provides key clues to the cause of valve deterioration. Numerical simulation, which is able to replicate and understand the dynamics of the valve, would benefit studies on heart valves surgical repair and prostheses design. Modeling and simulation of heart valves dynamics is a challenging biomechanical problem. Many researchers have taken various approaches to model the heart valve. But systematical categorization and development tendency of their research have never been discussed before. This paper reviews their models and divides them into wet models or dry models, in the light of whether considering blood flow and valve interaction. These simulations also can be categorized as native heart valve or artificial heart valve simulation by a different model prototype. The critical issues for future research are presented.

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Klyshnikov, K. Yu, E. A. Ovcharenko, A. V. Batranin, D. A. Dolgov, Yu N. Zakharov, K. S. Ivanov, Yu A. Kudryavtseva, Yu I. Shokin, and L. S. Barbarash. "Computer Modeling of Fluid Flow through the Heart Valve Bioprosthesis." Mathematical Biology and Bioinformatics 13, no. 2 (August 22, 2018): 337–47. http://dx.doi.org/10.17537/2018.13.337.

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The paper describes the features of in silico simulation of fluid flows of variable viscosity in the study of prosthetic heart valves. Computer modeling and its verification were performed on the example of the bioprosthesis "UniLine" (Russia) used in modern cardio-surgical practice. A spatial model of the object of investigation was obtained by the method of computer microtomography, followed by the reconstruction of the primitive grid in two-dimensional sections. In the numerical experiment, the immersed boundary method was used. Herein the interaction of a solid and a liquid as well as the impact of mechanics of deformation of the elements of the prosthesis, such as the winged apparatus, were taken into account. Verification of the calculation algorithm was performed in the pulsating flow setup in conditions of simulating the physiological parameters of hydrodynamics similar to those used in silico. In general, the results of the simulation are consistent with the quantitative and qualitative data of the hydrodynamic experiment. Thus, in the numerical simulation, a pressure gradient of 3.0 ± 1.1 mmHg was obtained, an effective orifice area of 2.8 cm2, a regurgitation volume of 0.1 ml/min. The experimental evaluation has shown the similar indicators: 6.5 ± 3.6 mmHg, 2.3 ± 0.6 cm2, 3.1 ± 1.7 ml/min, respectively. The described method demonstrates its promise and can be used in design and research tasks.

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Driessen, Niels J. B., Anita Mol, Carlijn V. C. Bouten, and Frank P. T. Baaijens. "Modeling the mechanics of tissue-engineered human heart valve leaflets." Journal of Biomechanics 40, no. 2 (January 2007): 325–34. http://dx.doi.org/10.1016/j.jbiomech.2006.01.009.

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Khalighi, Amir H., Andrew Drach, Robert C. Gorman, Joseph H. Gorman, and Michael S. Sacks. "Multi-resolution geometric modeling of the mitral heart valve leaflets." Biomechanics and Modeling in Mechanobiology 17, no. 2 (October 5, 2017): 351–66. http://dx.doi.org/10.1007/s10237-017-0965-8.

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Onishchenko, P. S., K. Yu Klyshnikov, M. A. Rezvova, and E. A. Ovcharenko. "The concept of automated functional design of heart valve prostheses." Complex Issues of Cardiovascular Diseases 10, no. 2 (September 2, 2021): 63–67. http://dx.doi.org/10.17802/2306-1278-2021-10-2s-63-67.

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Aim. To develop an algorithm for the automated functional design of the heart valve leaflet apparatus.Methods. The geometry of the aortic valve leaflet was designed in the Matlab programming environment (MathWorks, Massachusetts, USA). Numerical modeling of the opening process was performed using Abaqus/CAE (Dassault Systemes, France).Results. We developed an algorithm, with the help of which a set of models of the leaflet apparatus was designed. 8 models were subjected to numerical modeling of the stress-strain state. The locking pressure simulation has shown that the smallest von Mises stress value was recorded for a sample with a larger surface area of the leaflet belly and it equals 0.422 MPa. The results obtained show that the value of the radius of curvature significantly affects the behavior of the entire valve, which leads to the conclusion that it is necessary to carefully select the design of the valve apparatus for its correct functioning.Conclusion. The study provides the primary confirmation that the concept of the algorithm is efficient for the automated functional design of the aortic heart valve leaflet apparatus.

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Liang, Loh Quo, Kok Yin Hui, Nur Hazreen Mohd Hasni, and Mohd Azrul Hisham Mohd Adib. "Development of Heart Simulator (Heart-S) on the Left Ventricle for Measuring the Blood Circulation during Cardiac Cycle." Journal of Biomimetics, Biomaterials and Biomedical Engineering 36 (March 2018): 78–83. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.36.78.

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Heart is a complex structure which acts as a blood pump in mammal’s body. It is important to have detail study for the heart structure. Modeling of heart structure gives a better understanding and figure of the heart valve’s movement as well as the fluid flow movement in the heart chamber. In this paper, the heart simulator (Heart-S) on the left ventricle for measuring the blood circulation during cardiac cycle was proposed. Throughout the experimental modeling of heart valve structure by using rhythmic fluid flow in a closed chamber, the relationship between heart valve elasticity and heart valve angle position to the valve opening width were investigated. The main aspect of the present development is to provide a heart simulator apparatus to obtain data for development of artificial heart and for observing the blood circulation measurement. The result shows good agreement on valve elasticity and the velocity of the fluid from the vortex in the heart chamber can be found after the experiment. The novelty of this development is contributing to the study of the optimal vortex formation in the heart chamber and observe the blood circulation measurement.

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Zhou, Feng, Yuan Yuan Cui, Liang Liang Wu, Yin Chen, Jie Yang, and Nan Huang. "TRIZ Based Tool Management Applied in Mechanical Heart Valve Engineering Systems." Advanced Materials Research 569 (September 2012): 521–24. http://dx.doi.org/10.4028/www.scientific.net/amr.569.521.

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Artificial mechanical heart valve (MHV) replacement is the common cardiovascular surgical procedure, yet its effect is far from satisfaction. Most important reasons lie in the model design and choice of the materials in the fabrication of the prosthetic heart valves. Based on systematic design methodology of TRIZ theory (Russian acronym for Theory of Solving Inventive Problem), the device structure is analyzed by comparing the past successful designs generated during the evolution of MHV. This paper represents a modeling technique integrating the well-established TRIZ with the conflict and contradiction modeling, substance-field and product functional analysis tools and provides some important trends in evolutionary development of production systems in MHV design. By analyzing the structural behavior and material performance, a complex case study from the research of different structural patterns and characteristics of current tri-leaflet modeling shows the validity of TRIZ theory to guide MHV design.

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Mohd Adib, Mohd Azrul Hisham, and Nur Hazreen Mohd Hasni. "Degenerative vs Rigidity on Mitral Valve Leaflet Using Fluid Structure Interaction (FSI) Model." Journal of Biomimetics, Biomaterials and Biomedical Engineering 26 (February 2016): 60–65. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.26.60.

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The objectives of this study are to observe the deformation of mitral leaflet in systole condition and compare the rigidity of heart valve leaflet during systole and diastole conditions. Two-dimensional model of the mitral valve leaflet with ventricle were created using fluid structure interaction model in computational simulations. The result shows rigidity of heart valve leaflet always opposite to degeneration and the simulated displacement models corresponded to normal deformation in physical heart valve in systole condition. Modeling simulation techniques are very useful in the study of degenerative heart valve and the findings would allow us to optimize feature and geometries to reduced deformation of heart valve failure.

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Son, Jeongeun, Dongping Du, and Yuncheng Du. "Stochastic Modeling and Dynamic Analysis of the Cardiovascular System with Rotary Left Ventricular Assist Devices." Mathematical Problems in Engineering 2019 (January 10, 2019): 1–18. http://dx.doi.org/10.1155/2019/7179317.

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Left ventricular assist devices (LVADs) have been used for end-stage heart failure patients as a therapeutic option. The aortic valve plays a critical role in heart failure and its treatment with a LVAD. The cardiovascular-LVAD model is often used to investigate the physiological demands required by patients and predict the hemodynamic of the native heart supported with a LVAD. As it is a “bridge-to-recovery” treatment, it is important to maintain appropriate and active dynamics of the aortic valve and the cardiac output of the native heart, which requires that the LVAD pump be adjusted so that a proper balance between the blood contributed through the aortic valve and the pump is maintained. In this paper, we investigate how the pump power of the LVAD pump can affect the dynamic behaviors of the aortic valve for different levels of activity and different severities of heart failure. Our objective is to identify a critical value of the pump power (i.e., breakpoint) to ensure that the LVAD pump does not take over the pumping function in the cardiovascular-pump system and share the ejected blood with the left ventricle to help the heart to recover. In addition, the hemodynamic often involves variability due to patients’ heterogeneity and the stochastic nature of the cardiovascular system. The variability poses significant challenges to understanding dynamic behaviors of the aortic valve and cardiac output. A generalized polynomial chaos (gPC) expansion is used in this work to develop a stochastic cardiovascular-pump model for efficient uncertainty propagation, from which it is possible to rapidly calculate the variance in the aortic valve opening duration and the cardiac output in the presence of variability. The simulation results show that the gPC-based cardiovascular-pump model is a reliable platform that can provide useful information to understand the effect of the LVAD pump on the hemodynamic of the heart.

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Catalano, Chiara, and Salvatore Pasta. "On the Modeling of Transcatheter Therapies for the Aortic and Mitral Valves: A Review." Prosthesis 4, no. 1 (March 7, 2022): 102–12. http://dx.doi.org/10.3390/prosthesis4010011.

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Transcatheter aortic valve replacement (TAVR) has become a milestone for the management of aortic stenosis in a growing number of patients who are unfavorable candidates for surgery. With the new generation of transcatheter heart valves (THV), the feasibility of transcatheter mitral valve replacement (TMVR) for degenerated mitral bioprostheses and failed annuloplasty rings has been demonstrated. In this setting, computational simulations are modernizing the preoperative planning of transcatheter heart valve interventions by predicting the outcome of the bioprosthesis interaction with the human host in a patient-specific fashion. However, computational modeling needs to carry out increasingly challenging levels including the verification and validation to obtain accurate and realistic predictions. This review aims to provide an overall assessment of the recent advances in computational modeling for TAVR and TMVR as well as gaps in the knowledge limiting model credibility and reliability.

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Mohammadi, Hadi, and Kibret Mequanint. "An Inverse Numerical Approach for Modeling Aortic Heart Valve Leaflet Tissue Oxygenation." Cardiovascular Engineering and Technology 3, no. 1 (October 27, 2011): 73–79. http://dx.doi.org/10.1007/s13239-011-0068-0.

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Weinberg, Eli J., Danial Shahmirzadi, and Mohammad Reza Kaazempur Mofrad. "On the multiscale modeling of heart valve biomechanics in health and disease." Biomechanics and Modeling in Mechanobiology 9, no. 4 (January 12, 2010): 373–87. http://dx.doi.org/10.1007/s10237-009-0181-2.

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Kheradvar, Arash, Elliott M. Groves, Ahmad Falahatpisheh, Mohammad K. Mofrad, S. Hamed Alavi, Robert Tranquillo, Lakshmi P. Dasi, et al. "Emerging Trends in Heart Valve Engineering: Part IV. Computational Modeling and Experimental Studies." Annals of Biomedical Engineering 43, no. 10 (July 30, 2015): 2314–33. http://dx.doi.org/10.1007/s10439-015-1394-4.

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Sulejmani, Fatiesa, Andrés Caballero, Caitlin Martin, Thuy Pham, and Wei Sun. "Evaluation of transcatheter heart valve biomaterials: Computational modeling using bovine and porcine pericardium." Journal of the Mechanical Behavior of Biomedical Materials 97 (September 2019): 159–70. http://dx.doi.org/10.1016/j.jmbbm.2019.05.020.

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Wiener, Philip C., Ahmed Darwish, Evan Friend, Lyes Kadem, and Gregg S. Pressman. "Energy loss associated with in-vitro modeling of mitral annular calcification." PLOS ONE 16, no. 2 (February 16, 2021): e0246701. http://dx.doi.org/10.1371/journal.pone.0246701.

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Introduction Study aims were to compare hemodynamics and viscous energy dissipation (VED) in 3D printed mitral valves–one replicating a normal valve and the other a valve with severe mitral annular calcification (MAC). Patients with severe MAC develop transmitral gradients, without the commissural fusion typifying rheumatic mitral stenosis (MS), and may have symptoms similar to classical MS. A proposed mechanism relates to VED due to disturbed blood flow through the diseased valve into the ventricle. Methods A silicone model of a normal mitral valve (MV) was created using a transesophageal echocardiography dataset. 3D printed calcium phantoms were incorporated into a second valve model to replicate severe MAC. The synthetic MVs were tested in a left heart duplicator under rest and exercise conditions. Fine particles were suspended in a water/glycerol blood analogue for particle image velocimetry calculation of VED. Results Catheter mean transmitral gradients were slightly higher in the MAC valve compared to the normal MV, both at rest (3.2 vs. 1.3 mm Hg) and with exercise (5.9 vs. 5.0 mm Hg); Doppler gradients were 2.7 vs. 2.1 mm Hg at rest and 9.9 vs 8.2 mm Hg with exercise. VED was similar between the two valves at rest. During exercise, VED increased to a greater extent for the MAC valve (240%) versus the normal valve (127%). Conclusion MAC MS is associated with slightly increased transmitral gradients but markedly increased VED during exercise. These energy losses may contribute to the exercise intolerance and exertional dyspnea present in MAC patients.

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Nappi, Francesco, Laura Mazzocchi, Cristiano Spadaccio, David Attias, Irina Timofeva, Laurent Macron, Adelaide Iervolino, Simone Morganti, and Ferdinando Auricchio. "CoreValve vs. Sapien 3 Transcatheter Aortic Valve Replacement: A Finite Element Analysis Study." Bioengineering 8, no. 5 (April 27, 2021): 52. http://dx.doi.org/10.3390/bioengineering8050052.

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Aim: to investigate the factors implied in the development of postoperative complications in both self-expandable and balloon-expandable transcatheter heart valves by means of finite element analysis (FEA). Materials and methods: FEA was integrated into CT scans to investigate two cases of postoperative device failure for valve thrombosis after the successful implantation of a CoreValve and a Sapien 3 valve. Data were then compared with two patients who had undergone uncomplicated transcatheter heart valve replacement (TAVR) with the same types of valves. Results: Computational biomechanical modeling showed calcifications persisting after device expansion, not visible on the CT scan. These calcifications determined geometrical distortion and elliptical deformation of the valve predisposing to hemodynamic disturbances and potential thrombosis. Increased regional stress was also identified in correspondence to the areas of distortion with the associated paravalvular leak. Conclusion: the use of FEA as an adjunct to preoperative imaging might assist patient selection and procedure planning as well as help in the detection and prevention of TAVR complications.

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Lee, Chung-Hao, Devin W. Laurence, Colton J. Ross, Katherine E. Kramer, Anju R. Babu, Emily L. Johnson, Ming-Chen Hsu, et al. "Mechanics of the Tricuspid Valve—From Clinical Diagnosis/Treatment, In-Vivo and In-Vitro Investigations, to Patient-Specific Biomechanical Modeling." Bioengineering 6, no. 2 (May 22, 2019): 47. http://dx.doi.org/10.3390/bioengineering6020047.

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Proper tricuspid valve (TV) function is essential to unidirectional blood flow through the right side of the heart. Alterations to the tricuspid valvular components, such as the TV annulus, may lead to functional tricuspid regurgitation (FTR), where the valve is unable to prevent undesired backflow of blood from the right ventricle into the right atrium during systole. Various treatment options are currently available for FTR; however, research for the tricuspid heart valve, functional tricuspid regurgitation, and the relevant treatment methodologies are limited due to the pervasive expectation among cardiac surgeons and cardiologists that FTR will naturally regress after repair of left-sided heart valve lesions. Recent studies have focused on (i) understanding the function of the TV and the initiation or progression of FTR using both in-vivo and in-vitro methods, (ii) quantifying the biomechanical properties of the tricuspid valve apparatus as well as its surrounding heart tissue, and (iii) performing computational modeling of the TV to provide new insight into its biomechanical and physiological function. This review paper focuses on these advances and summarizes recent research relevant to the TV within the scope of FTR. Moreover, this review also provides future perspectives and extensions critical to enhancing the current understanding of the functioning and remodeling tricuspid valve in both the healthy and pathophysiological states.

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Cella, Laura, Raffaele Liuzzi, Manuel Conson, Vittoria D’Avino, Marco Salvatore, and Roberto Pacelli. "Multivariate Normal Tissue Complication Probability Modeling of Heart Valve Dysfunction in Hodgkin Lymphoma Survivors." International Journal of Radiation Oncology*Biology*Physics 87, no. 2 (October 2013): 304–10. http://dx.doi.org/10.1016/j.ijrobp.2013.05.049.

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Aggarwal, Ankush, and Michael S. Sacks. "An inverse modeling approach for semilunar heart valve leaflet mechanics: exploitation of tissue structure." Biomechanics and Modeling in Mechanobiology 15, no. 4 (October 8, 2015): 909–32. http://dx.doi.org/10.1007/s10237-015-0732-7.

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Roy, Dibyendu, Oishee Mazumder, Aniruddha Sinha, and Sundeep Khandelwal. "Multimodal cardiovascular model for hemodynamic analysis: Simulation study on mitral valve disorders." PLOS ONE 16, no. 3 (March 4, 2021): e0247921. http://dx.doi.org/10.1371/journal.pone.0247921.

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Valvular heart diseases are a prevalent cause of cardiovascular morbidity and mortality worldwide, affecting a wide spectrum of the population. In-silico modeling of the cardiovascular system has recently gained recognition as a useful tool in cardiovascular research and clinical applications. Here, we present an in-silico cardiac computational model to analyze the effect and severity of valvular disease on general hemodynamic parameters. We propose a multimodal and multiscale cardiovascular model to simulate and understand the progression of valvular disease associated with the mitral valve. The developed model integrates cardiac electrophysiology with hemodynamic modeling, thus giving a broader and holistic understanding of the effect of disease progression on various parameters like ejection fraction, cardiac output, blood pressure, etc., to assess the severity of mitral valve disorders, naming Mitral Stenosis and Mitral Regurgitation. The model mimics an adult cardiovascular system, comprising a four-chambered heart with systemic, pulmonic circulation. The simulation of the model output comprises regulated pressure, volume, and flow for each heart chamber, valve dynamics, and Photoplethysmogram signal for normal physiological as well as pathological conditions due to mitral valve disorders. The generated physiological parameters are in agreement with published data. Additionally, we have related the simulated left atrium and ventricle dimensions, with the enlargement and hypertrophy in the cardiac chambers of patients with mitral valve disorders, using their Electrocardiogram available in Physionet PTBI dataset. The model also helps to create ‘what if’ scenarios and relevant analysis to study the effect in different hemodynamic parameters for stress or exercise like conditions.

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Smirnov, A. A., A. L. Ovsepyan, P. A. Kvindt, F. N. Paleev, E. V. Borisova, and E. V. Yakovlev. "Finite element analysis in the modeling of the heart and aorta structures." Almanac of Clinical Medicine 49, no. 6 (November 9, 2021): 375–84. http://dx.doi.org/10.18786/2072-0505-2021-49-043.

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Rationale: 3D modeling of various anatomical structures has recently become a separate area of topographical, anatomical, and biomechanical studies. Current in vivo visualization methods and quantitative analysis in silico allow to perform the precise modeling of these processes aimed at investigation into the pathophysiology of cardiovascular disorders, risk prediction, planning of surgical interventions and virtual refinement of their separate stages.Aim: To develop tools for elaboration, analysis and validation of personalized models of various structures of the heart and aortal arch taking into account their morphological characteristics.Materials and methods: We used the results of 14 computed tomography studies from randomized patients without any disease or anomaly of the heart, aortic valve and aortal bulb. The analysis and subsequent transformation of the images were done with Vidar DICOM Viewer, SolidWorks 2016, VMTKLab software. For the FSI modeling of the aortic arch based on the results of functional multiaxial computed (MAC) coronarography (a female patient of 55 years) we developed a personalized model of the ascending aorta and aortic arch at the beginning of the systole. Using HyperMesh software (Altair Engineering Inc., USA) we have built a network of finite element of the luminal area, adventitia, and aortic media. To model mechanical properties of the aortic structures we used an anisotropic hyperelastic material model by Holzapfel – Gasser – Ogden. Material modeling, choice of the limiting antecedents, and analysis of fluid-structure interaction were performed with Abaqus CAE 6.14 software (Simulia, Johnston, USA). Adaptive image meshing by Young was used to elaborate the finite element template of the left ventricle. The algorithm was realized within the IDE PyCharm software media in Python 3.7. The algorithm was realized based on the open-source libraries OpenCV, NumPy, Matplotlib, and SciPy.Results: The first stage of the development of the aortic valve model included the design of its virtual 3D template. Thereafter, a cohesive geometric model was elaborated. Subsequent stage of the work included the transformation of the aortic valve geometric model into the parametric one. This was done through the use of the “Equations” tool within the SolidWorks. No problems with geometry of the model during its deformation were identified. Aortic segment modeling was based on the data obtained by functional MAC coronarography. Based on this and on Inobitec Dicom Viewer software, we generated a multiplane reconstruction of the zone of interest including anatomical structure of the heart and aortic valve. With the resulting set of contours, we created a 3D model, which then was converted into a polygonal stereolithographic model. We developed an algorithm for adaptive meshing to elaborate a polygonal template capable of deformation that can be used for registration both with the net methods (B-Spline) and based on the image characteristics (homologous pixels). Conclusion: The resulting parametric 3D model of the aortic valve anatomical structures is capable of adequate transformation of its geometry under external factors. It can be used in simulators of endovascular cardiosurgical procedures.

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Kadhim, Saleem Khalefa, Mohammad Shakir Nasif, Hussain H. Al-Kayiem, and Rafat Al-Waked. "Computational fluid dynamics simulation of blood flow profile and shear stresses in bileaflet mechanical heart valve by using monolithic approach." SIMULATION 94, no. 2 (June 7, 2017): 93–104. http://dx.doi.org/10.1177/0037549717712603.

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Bileaflet mechanical heart valves (BMHVs) are widely used to replace diseased heart valves. However, patients may suffer from implant complications, such as platelet aggregation and damage to blood cells, which could lead to BMHV failure. These complications are related to the blood flow patterns in the BMHV. A three-dimensional computational fluid dynamic (CFD) model was developed to investigate blood hydrodynamics and shear stresses at different cardiac cycles. A user-defined function (UDF) code was developed to model the valve leaflet motion. This UDF updates the tetrahedral mesh according to the location of the valve leaflet, which enables modeling of complicated moving geometries and achieves solution convergence with ease without the need to adjust the relaxation factor values. The agreement between the experimental and numerical results indicates that the developed model could be used with confidence to simulate BMHV motion and blood flow. Furthermore, valve leaflet and valve pivot were found to be continuously exposed to shear stresses higher than 52.3 Pa which according to previous research findings may cause damage to blood platelets.

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Kumar, Gideon Praveen, and Lazar Mathew. "DESIGN OF A NOVEL STENTED VALVE AND 3D MODELING OF ITS IMPLANTATION IN THE AORTA." Biomedical Engineering: Applications, Basis and Communications 22, no. 02 (April 2010): 157–61. http://dx.doi.org/10.4015/s101623721000189x.

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Objective: To design a novel percutaneous stented valve and model its implantation in the aorta.Background: The dimensions of stented aortic valve components govern its ability to prevent backflow of blood into the left ventricle. Whilst the theoretical parameters for the best stent performance have already been established, an effective valve model and its suitability along with the stent are lacking.Methods: This article discusses the design of a stented valve suitable for percutaneous aortic valve replacement. Steps involved in 3D CAD-based geometric modeling of the stented aortic valve and its implantation in the aorta are presented. Conceptual designing of individual components was used to build the total geometric model.Results: A novel geometric model of percutaneous stented aortic valve was generated. The improved design enhances its performance during and after implantation.Conclusion: The blunt hooks in the stent model prevent its migration in either direction by getting embedded in the aortic endothelium. This novel stent aortic valve may be of great interest to designers of future bioprosthetic heart valve models, as well as to surgeons involved in minimally invasive valve surgeries.

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Klyshnikov, K. Yu, E. A. Ovcharenko, M. A. Rezvova, T. V. Glushkova, and L. S. Barbarash. "POTENTIAL BENEFITS FOR USING ePTFE AS A MATERIAL FOR PROSTHETIC HEART VALVES." Complex Issues of Cardiovascular Diseases 7, no. 2 (June 30, 2018): 79–88. http://dx.doi.org/10.17802/2306-1278-2018-7-2-79-88.

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Background The current study highlights potential benefits of using ePTFE, a polymeric material, as the main component suitable for fabrication of prosthetic heart valves. Novel polymeric materials seem to be promising for replacing biological elements commonly used in medical products for cardiovascular surgery. High biocompatibility and mechanical properties prolong their lifespan during direct blood contact. Nevertheless, it is necessary to conduct a series of specific tests to determine their properties and benefits of their application. Despite well-known biological properties of ePTFE, there are few studies assessing it as a material for heart valve leaflets. Aim To evaluate the mechanical properties of the commercially available sample of ePTFE and to conduct a numerical experiment assessing its potential for the application. Methods The polymer properties (Gore & Associates Inc., USA) were evaluated under uniaxial tension in two mutually perpendicular directions to determine the degree of anisotropy of the material. A xenopericardial patch (ZAO “NeoCor”, Russia), routinely used for the fabrication of bioprosthetic leaflets, was taken as the control sample. The spatial model of the investigated material was carried out in CAD SolidWorks 2016 (Dassault Systemes, USA). Numerical modeling of the samples was performed with the finite element method using the orthotropic material model in the Abaqus/CAE (Dassault Systemes, USA). Results There are significant difference found in the mechanical properties of the studied materials: the tension at stretching of ePTFE in the longitudinal and transverse directions differed from xenopericardium by 1.9 and 7.5 times, respectively (p<0.05). The elongation before rupture of ePTFE in direction I and direction II was greater than that of xenopericardium (2.39 vs. 1.9 times, respectively). Numerical modeling demonstrated insignificant qualitative differences in the valve opening while applying pressure equal to normal physiological pressure>< 0.05). The elongation before rupture of ePTFE in direction I and direction II was greater than that of xenopericardium (2.39 vs. 1.9 times, respectively). Numerical modeling demonstrated insignificant qualitative differences in the valve opening while applying pressure equal to normal physiological pressure and low pressure. In addition, the zones of high stress in commissural racks, which are critical zones for fatigue resistance, have been identified, albeit require additional in vitro research. Conclusion Mechanical properties of ePTFE suggests it to be a promising polymeric material suitable for fabrication of flexible leaflets of the heart valve prosthesis. It has similar leaflet functioning, compared with the xenopericardium sample, routinely used in manufacturing. ePTFE is more resistant to rupture, which confirms its greater fatigue strength. However, it requires further study by advanced methods.

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Pasta, Salvatore, Stefano Cannata, Giovanni Gentile, Valentina Agnese, Giuseppe Maria Raffa, Michele Pilato, and Caterina Gandolfo. "Transcatheter Heart Valve Implantation in Bicuspid Patients with Self-Expanding Device." Bioengineering 8, no. 7 (July 1, 2021): 91. http://dx.doi.org/10.3390/bioengineering8070091.

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Bicuspid aortic valve (BAV) patients are conventionally not treated by transcathether aortic valve implantation (TAVI) because of anatomic constraint with unfavorable outcome. Patient-specific numerical simulation of TAVI in BAV may predict important clinical insights to assess the conformability of the transcathether heart valves (THV) implanted on the aortic root of members of this challenging patient population. We aimed to develop a computational approach and virtually simulate TAVI in a group of n.6 stenotic BAV patients using the self-expanding Evolut Pro THV. Specifically, the structural mechanics were evaluated by a finite-element model to estimate the deformed THV configuration in the oval bicuspid anatomy. Then, a fluid–solid interaction analysis based on the smoothed-particle hydrodynamics (SPH) technique was adopted to quantify the blood-flow patterns as well as the regions at high risk of paravalvular leakage (PVL). Simulations demonstrated a slight asymmetric and elliptical expansion of the THV stent frame in the BAV anatomy. The contact pressure between the luminal aortic root surface and the THV stent frame was determined to quantify the device anchoring force at the level of the aortic annulus and mid-ascending aorta. At late diastole, PVL was found in the gap between the aortic wall and THV stent frame. Though the modeling framework was not validated by clinical data, this study could be considered a further step towards the use of numerical simulations for the assessment of TAVI in BAV, aiming at understanding patients not suitable for device implantation on an anatomic basis.

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Vukicevic, Marija, Kinan Carlos El Tallawi, Eleonora Avenatti, Su Min Chang, Colin Barker, and Stephen Little. "3D PRINTED MODELING OF RIGHT VENTRICLE AND TRICUSPID VALVE FROM CT IMAGES FOR STRUCTURAL HEART INTERVENTIONS." Journal of the American College of Cardiology 71, no. 11 (March 2018): A1352. http://dx.doi.org/10.1016/s0735-1097(18)31893-x.

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Morshed, Monjur, Shaikh Anowarul Fattah, and Mohammad Saquib. "Automated Heart Valve Disorder Detection Based on PDF Modeling of Formant Variation Pattern in PCG Signal." IEEE Access 10 (2022): 27330–42. http://dx.doi.org/10.1109/access.2022.3157305.

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Zhu, Amadeus S., and K. Jane Grande-Allen. "Erratum to “Heart valve tissue engineering for valve replacement and disease modeling”, [Curr Opin Biomed Eng, Volume 5, March 2018, Pages 35–41]." Current Opinion in Biomedical Engineering 19 (September 2021): 100269. http://dx.doi.org/10.1016/j.cobme.2021.100269.

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Ge, Liang, Hwa-Liang Leo, Fotis Sotiropoulos, and Ajit P. Yoganathan. "Flow in a Mechanical Bileaflet Heart Valve at Laminar and Near-Peak Systole Flow Rates: CFD Simulations and Experiments." Journal of Biomechanical Engineering 127, no. 5 (March 31, 2005): 782–97. http://dx.doi.org/10.1115/1.1993665.

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Time-accurate, fully 3D numerical simulations and particle image velocity laboratory experiments are carried out for flow through a fully open bileaflet mechanical heart valve under steady (nonpulsatile) inflow conditions. Flows at two different Reynolds numbers, one in the laminar regime and the other turbulent (near-peak systole flow rate), are investigated. A direct numerical simulation is carried out for the laminar flow case while the turbulent flow is investigated with two different unsteady statistical turbulence modeling approaches, unsteady Reynolds-averaged Navier-Stokes (URANS) and detached-eddy simulation (DES) approach. For both the laminar and turbulent cases the computed mean velocity profiles are in good overall agreement with the measurements. For the turbulent simulations, however, the comparisons with the measurements demonstrate clearly the superiority of the DES approach and underscore its potential as a powerful modeling tool of cardiovascular flows at physiological conditions. The study reveals numerous previously unknown features of the flow.

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Mohammadi, Hadi, Fereshteh Bahramian, and Wankei Wan. "Advanced modeling strategy for the analysis of heart valve leaflet tissue mechanics using high-order finite element method." Medical Engineering & Physics 31, no. 9 (November 2009): 1110–17. http://dx.doi.org/10.1016/j.medengphy.2009.07.012.

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Paulsen, Michael J., Patpilai Kasinpila, Annabel M. Imbrie-Moore, Hanjay Wang, Camille E. Hironaka, Tiffany K. Koyano, Robyn Fong, et al. "Modeling conduit choice for valve-sparing aortic root replacement on biomechanics with a 3-dimensional–printed heart simulator." Journal of Thoracic and Cardiovascular Surgery 158, no. 2 (August 2019): 392–403. http://dx.doi.org/10.1016/j.jtcvs.2018.10.145.

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Sacks, Michael S., Emma Lejeune, and Alex Khang. "A Multi-Scale Modeling Approach to Determine 3D Heart Valve Interstitial Cell Biophysical Behavior in a Hydrogel Environment." Biophysical Journal 118, no. 3 (February 2020): 155a. http://dx.doi.org/10.1016/j.bpj.2019.11.964.

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Wang, Z. C., Q. Yuan, H. W. Zhu, B. S. Shen, and D. Tang. "Computational Modeling for Fluid–Structure Interaction of Bioprosthetic Heart Valve with Different Suture Density: Comparison with Dynamic Structure Simulation." International Journal of Pattern Recognition and Artificial Intelligence 31, no. 11 (April 4, 2017): 1757007. http://dx.doi.org/10.1142/s0218001417570075.

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In this paper, a parametric geometry model based on elliptic and conic surfaces was developed for bioprosthetic heart valve (BHV) simulation. The valve material was modeled by a hyperelastic nonlinear anisotropic solid model. Different suture densities could be substituted by various bonded points between artery vessel and the leaflets as boundary conditions in the computational modeling. Besides these two assumptions that dynamic structure (DS) and fluid–structure interaction (FSI) both shared, the latter need incompressible viscous Newton fluid model to depict bloodstream passing through the BHV. Immersed boundary (IB) method was introduced to solve the FSI simulation. In addition, the DS analysis applied transvalvular pressure on the valve while FSI had left ventricular pressure on fluid inlet as initials. There was inconsistency between the moments of the maximum deformation and the maximum loading in both simulations. Although a similar trend of deformation lagging the load was viewed, the extent of delay in FSI was much smaller compared with that in DS simulation. The deformed profiles in cross-sectional views were shown in one picture to illustrate different dynamic responses caused by distinct assumptions. Percent of open area at the moments when the maximum deformation occurred was defined to show which calculation achieved better approximation for precise hemodynamics. Fixed point was given as boundaries between BHV and artery in the modeling part. Calculations showed that the more the fixed points in this bonded contact, the lower the principal stress was. The maximum shear stress showed a different trend. It had a different trend. Stress concentration in the conjunction area made it high-risk to be teared. Different suture densities had significant impaction in FSI simulations. With that analysis our work achieved a more comprehensive simulation to describe true hemodynamics of a BHV implanted in artery. The artery vessel had particular dynamic response under such assumptions, gradient existed in the maximum principal stress distribution diagram, from inner wall through which blood passing to the outer wall. Results showed a large suture density was suggested in BHV implantation.

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Theis, Jeanne L., and Timothy M. Olson. "Whole Genome Sequencing in Hypoplastic Left Heart Syndrome." Journal of Cardiovascular Development and Disease 9, no. 4 (April 15, 2022): 117. http://dx.doi.org/10.3390/jcdd9040117.

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Hypoplastic left heart syndrome (HLHS) is a genetically complex disorder. Whole genome sequencing enables comprehensive scrutiny of single nucleotide variants and small insertions/deletions, within both coding and regulatory regions of the genome, revolutionizing susceptibility-gene discovery research. Because millions of rare variants comprise an individual genome, identification of alleles linked to HLHS necessitates filtering algorithms based on various parameters, such as inheritance, enrichment, omics data, known genotype–phenotype associations, and predictive or experimental modeling. In this brief review, we highlight family and cohort-based strategies used to analyze whole genome sequencing datasets and identify HLHS candidate genes. Key findings include compound and digenic heterozygosity among several prioritized genes and genetic associations between HLHS and bicuspid aortic valve or cardiomyopathy. Together with findings of independent genomic investigations, MYH6 has emerged as a compelling disease gene for HLHS and other left-sided congenital heart diseases.

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van der Horst, Arjen, Frits L. Boogaard, Marcel van't Veer, Marcel C. M. Rutten, Nico H. J. Pijls, and Frans N. van de Vosse. "Towards Patient-Specific Modeling of Coronary Hemodynamics in Healthy and Diseased State." Computational and Mathematical Methods in Medicine 2013 (2013): 1–15. http://dx.doi.org/10.1155/2013/393792.

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A model describing the primary relations between the cardiac muscle and coronary circulation might be useful for interpreting coronary hemodynamics in case multiple types of coronary circulatory disease are present. The main contribution of the present study is the coupling of a microstructure-based heart contraction model with a 1D wave propagation model. The 1D representation of the vessels enables patient-specific modeling of the arteries and/or can serve as boundary conditions for detailed 3D models, while the heart model enables the simulation of cardiac disease, with physiology-based parameter changes. Here, the different components of the model are explained and the ability of the model to describe coronary hemodynamics in health and disease is evaluated. Two disease types are modeled: coronary epicardial stenoses and left ventricular hypertrophy with an aortic valve stenosis. In all simulations (healthy and diseased), the dynamics of pressure and flow qualitatively agreed with observations described in literature. We conclude that the model adequately can predict coronary hemodynamics in both normal and diseased state based on patient-specific clinical data.

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Toeg, Hadi Daood, Ovais Abessi, Talal Al-Atassi, Laurent de Kerchove, Gebrine El-Khoury, Michel Labrosse, and Munir Boodhwani. "Finding the ideal biomaterial for aortic valve repair with ex vivo porcine left heart simulator and finite element modeling." Journal of Thoracic and Cardiovascular Surgery 148, no. 4 (October 2014): 1739–45. http://dx.doi.org/10.1016/j.jtcvs.2014.05.004.

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Emmert, Maximilian Y., Boris A. Schmitt, Sandra Loerakker, Bart Sanders, Hendrik Spriestersbach, Emanuela S. Fioretta, Leon Bruder, et al. "Computational modeling guides tissue-engineered heart valve design for long-term in vivo performance in a translational sheep model." Science Translational Medicine 10, no. 440 (May 9, 2018): eaan4587. http://dx.doi.org/10.1126/scitranslmed.aan4587.

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Liang, Liang, and Bill Sun. "A Proof of Concept Study of Using Machine-Learning in Artificial Aortic Valve Design: From Leaflet Design to Stress Analysis." Bioengineering 6, no. 4 (November 8, 2019): 104. http://dx.doi.org/10.3390/bioengineering6040104.

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Artificial heart valves, used to replace diseased human heart valves, are life-saving medical devices. Currently, at the device development stage, new artificial valves are primarily assessed through time-consuming and expensive benchtop tests or animal implantation studies. Computational stress analysis using the finite element (FE) method presents an attractive alternative to physical testing. However, FE computational analysis requires a complex process of numeric modeling and simulation, as well as in-depth engineering expertise. In this proof of concept study, our objective was to develop machine learning (ML) techniques that can estimate the stress and deformation of a transcatheter aortic valve (TAV) from a given set of TAV leaflet design parameters. Two deep neural networks were developed and compared: the autoencoder-based ML-models and the direct ML-models. The ML-models were evaluated through Monte Carlo cross validation. From the results, both proposed deep neural networks could accurately estimate the deformed geometry of the TAV leaflets and the associated stress distributions within a second, with the direct ML-models (ML-model-d) having slightly larger errors. In conclusion, although this is a proof-of-concept study, the proposed ML approaches have demonstrated great potential to serve as a fast and reliable tool for future TAV design.

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Ooms, Joris, Magali Minet, Joost Daemen, and Nicolas Van Mieghem. "Pre-procedural planning of transcatheter mitral valve replacement in mitral stenosis with multi-detector tomography-derived 3D modeling and printing: a case report." European Heart Journal - Case Reports 4, no. 3 (May 10, 2020): 1–6. http://dx.doi.org/10.1093/ehjcr/ytaa098.

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Abstract Background Transcatheter mitral valve replacement (TMVR) may be a valuable treatment option for mitral annular calcification and severe mitral stenosis (MS) in patients at high operative risk. Pre-procedural virtual and printed simulations may aid in procedure planning, device sizing, and mitigate complications such as valve embolization or left ventricular outflow tract (LVOT) obstruction. Case summary We describe a case of TMVR in which multi-detector computed tomography (MDCT) derived, three-dimensional virtual planning and a 3D-printed model of the patients’ left heart provided enhanced understanding of an individual patient’s unique anatomy to determine feasibility, device sizing, and risk stratification. This resulted in deployment of an adequately sized valve. Post-TMVR LVOT obstruction was treated with LVOT balloon dilatation and percutaneous transluminal septal myocardial ablation. Discussion Advanced MDCT-derived planning techniques introduce consistent 3D modeling and printing to enhance understanding of intracardiac anatomical relationships and test device implantation. Still, static measurements do not feature haemodynamic factors, tissue, or device characteristics and do not predict device host interaction. Transcatheter mitral valve replacement is feasible in MS when adequately pre-procedurally planned. Multi-detector computed tomography-derived, 3D, virtual and printed models contribute to adequate planning in terms of determining patient eligibility, procedure feasibility, and device sizing. However, static 3D modeling cannot completely eliminate the risk of peri-procedural complications.

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Sacks, Michael S. "A Macro-Micro Modeling Approach to Determine In-Situ Heart Valve Interstitial Cell Contractile Behaviors in Native and Synthetic Environments." Biophysical Journal 116, no. 3 (February 2019): 322a. http://dx.doi.org/10.1016/j.bpj.2018.11.1747.

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Kamensky, David, John A. Evans, Ming-Chen Hsu, and Yuri Bazilevs. "Projection-based stabilization of interface Lagrange multipliers in immersogeometric fluid–thin structure interaction analysis, with application to heart valve modeling." Computers & Mathematics with Applications 74, no. 9 (November 2017): 2068–88. http://dx.doi.org/10.1016/j.camwa.2017.07.006.

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Lavrenko, V. A., P. I. Zolkin, V. N. Talash, V. F. Tatarinov, and V. I. Kostikov. "Experimental modeling of interaction between the carbon pyroceram heart valve and human blood plasma and formation of a protective nanosized coating." Powder Metallurgy and Metal Ceramics 50, no. 1-2 (May 2011): 62–66. http://dx.doi.org/10.1007/s11106-011-9303-3.

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Adler, D., S. D. Nikolic, E. H. Sonnenblick, and E. L. Yellin. "Modeling the transient response to volume perturbations in the beating heart by the difference equation method." American Journal of Physiology-Heart and Circulatory Physiology 266, no. 4 (April 1, 1994): H1657—H1671. http://dx.doi.org/10.1152/ajpheart.1994.266.4.h1657.

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Discrete theoretical methods, compatible with the discrete features of the beating heart, are used together with experimental study to attain a quantitative understanding of the transient response to a volume perturbation and of sustained mechanical alternans (SMA) in the beating heart. This is done in three stages. In stage A, a first-order difference equation describes the stroke volume (SV) response due to the Frank-Starling mechanism. It is shown that the value of gamma, the slope of the SV-end-diastolic volume curve, determines the type of response obtained because of a perturbation: 1) nonoscillatory decay for gamma < 1,2) oscillatory decay for 1 < gamma < 2, 3) SMA for gamma = 2, and 4) chaotic response for gamma > 2. In stage B, when the effect of each SV change on the successive end-diastolic aortic pressure (P) is considered, SV response to a perturbation is determined by a second-order difference equation. The solution of this equation shows that the response is determined by gamma and by the afterload factor lambda 1 = alpha 1.delta, where alpha 1 = delta Pj + 1/delta SVj and delta = delta SVj + 1/delta Pj + 1. The responses are a nonoscillatory decay for lambda 1 < 1 - gamma (type 1), oscillatory decay for 1 - (gamma/2) > lambda 1 > 1 - gamma (type 2), SMA for lambda 1 = 1 - gamma/2 (type 3), and 2:1 electrical-mechanical response for lambda 1 > 1 - gamma/2 (type 4). In stage C, a single volume perturbation, delta SVj, will directly affect not only Pj + 1 but also the subsequent values of P. Filling volume perturbations performed with a mitral valve occluder in eight anesthetized dogs led only to type 1 and 2 responses. The responses predicted by the model (using the experimental values of gamma and lambda 1) in each of the eight open-chest dogs are compatible with the experimental responses, suggesting that it is unlikely that SMA is initiated and maintained by variations in preload and afterload.

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Guo, Yong Cun, Min Jian Xing, and Kun Hu. "Modeling and Simulation of the Hydraulic Height Adjustment System of Mobile Tail Based on AMESim." Advanced Materials Research 591-593 (November 2012): 611–14. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.611.

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Mobile tail is an important part of the telescopic belt conveyor. It relies mainly on the hydraulic system to achieve its various functions, while the hydraulic height adjustment system is the basis of its different functions. So the operational principle of hydraulic height adjustment system of mobile tail was analyzed in this paper. Parameters which may affect the dynamic process were analyzed. Software AMESim was used to model and simulate the dynamic process. The velocity and displacement of piston and the pressure of the hydraulic cylinder were calculated by the software. Different pump flow and different heart diameter of one-way valve were used to analyze their influence on dynamic process, which provide a reference to the optimal design of hydraulic system of mobile tail.

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Ginty, Olivia K., John M. Moore, Yuanwei Xu, Wenyao Xia, Satoru Fujii, Daniel Bainbridge, Terry M. Peters, Bob B. Kiaii, and Michael W. A. Chu. "Dynamic Patient-Specific Three-Dimensional Simulation of Mitral Repair." Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery 13, no. 1 (January 2018): 11–22. http://dx.doi.org/10.1097/imi.0000000000000463.

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Objective Planned mitral repair strategies are generally established from preoperative echocardiography; however, specific details of the repair are often determined intraoperatively. We propose that three-dimensional printed, patient-specific, dynamic mitral valve models may help surgeons plan and trial all the details of a specific patient's mitral repair preoperatively. Methods Using preoperative echocardiography, segmentation, modeling software, and three-dimensional printing, we created dynamic, high-fidelity, patient-specific mitral valve models including the subvalvular apparatus. We assessed the accuracy of 10 patient mitral valve models anatomically and functionally in a heart phantom simulator, both objectively by blinded echocardiographic assessment, and subjectively by two mitral repair experts. After this, we attempted model mitral repair and compared the outcomes with postoperative echocardiography. Results Model measurements were accurate when compared with patients on anterior-posterior diameter, circumference, and anterior leaflet length; however, less accurate on posterior leaflet length. On subjective assessment, Likert scores were high at 3.8 ± 0.4 and 3.4 ± 0.7, suggesting good fidelity of the dynamic model echocardiogram and functional model in the phantom to the preoperative three-dimensional echocardiogram, respectively. Mitral repair was successful in all 10 models with significant reduction in mitral insufficiency. In two models, mitral repair was performed twice, using two different surgical techniques to assess which provided a better outcome. When compared with the actual patient mitral repair outcome, the repaired models compared favorably. Conclusions Complex mitral valve modeling seems to predict an individual patient's mitral anatomy well, before surgery. Further investigation is required to determine whether deliberate preoperative practice can improve mitral repair outcomes.

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Journal articles on the topic 'Heart valve modeling'

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