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Suriany S, Liu H, Cheng AL, Wenby R, Patel N, Badran S, Meiselman HJ, Denton C, Coates TD, Wood JC, Detterich JA. Decreased erythrocyte aggregation in Glenn and Fontan: univentricular circulation as a rheologic disease model. Pediatr Res 2024; 95:1335-1345. [PMID: 38177250 DOI: 10.1038/s41390-023-02969-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/19/2023] [Accepted: 12/04/2023] [Indexed: 01/06/2024]
Abstract
BACKGROUND In the Fontan palliation for single ventricle heart disease (SVHD), pulmonary blood flow is non-pulsatile/passive, low velocity, and low shear, making viscous power loss a critical determinant of cardiac output. The rheologic properties of blood in SVHD patients are essential for understanding and modulating their limited cardiac output and they have not been systematically studied. We hypothesize that viscosity is decreased in single ventricle circulation. METHODS We evaluated whole blood viscosity, red blood cell (RBC) aggregation, and RBC deformability to evaluate changes in healthy children and SVHD patients. We altered suspending media to understand cellular and plasma differences contributing to rheologic differences. RESULTS Whole blood viscosity was similar between SVHD and healthy at their native hematocrits, while viscosity was lower at equivalent hematocrits for SVHD patients. RBC deformability is increased, and RBC aggregation is decreased in SVHD patients. Suspending SVHD RBCs in healthy plasma resulted in increased RBC aggregation and suspending healthy RBCs in SVHD plasma resulted in lower RBC aggregation. CONCLUSIONS Hematocrit corrected blood viscosity is lower in SVHD vs. healthy due to decreased RBC aggregation and higher RBC deformability, a viscous adaptation of blood in patients whose cardiac output is dependent on minimizing viscous power loss. IMPACT Patients with single ventricle circulation have decreased red blood cell aggregation and increased red blood cell deformability, both of which result in a decrease in blood viscosity across a large shear rate range. Since the unique Fontan circulation has very low-shear and low velocity flow in the pulmonary arteries, blood viscosity plays an increased role in vascular resistance, therefore this work is the first to describe a novel mechanism to target pulmonary vascular resistance as a modifiable risk factor. This is a novel, modifiable risk factor in this patient population.
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Affiliation(s)
- Silvie Suriany
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Honglei Liu
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Andrew L Cheng
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Rosalinda Wenby
- Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Neil Patel
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Sarah Badran
- Division of Pediatric and Congenital Cardiology, Helen Devos Children's Hospital at Spectrum Health, Grand Rapids, MI, USA
- Division of Cardiology, Department of Medicine, Michigan State University, East Lansing, MI, USA
| | - Herbert J Meiselman
- Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Christopher Denton
- Division of Hematology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Thomas D Coates
- Division of Hematology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - John C Wood
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Jon A Detterich
- Division of Cardiology, Children's Hospital of Los Angeles, Los Angeles, CA, USA.
- Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
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Schwarz EL, Pegolotti L, Pfaller MR, Marsden AL. Beyond CFD: Emerging methodologies for predictive simulation in cardiovascular health and disease. BIOPHYSICS REVIEWS 2023; 4:011301. [PMID: 36686891 PMCID: PMC9846834 DOI: 10.1063/5.0109400] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 12/12/2022] [Indexed: 01/15/2023]
Abstract
Physics-based computational models of the cardiovascular system are increasingly used to simulate hemodynamics, tissue mechanics, and physiology in evolving healthy and diseased states. While predictive models using computational fluid dynamics (CFD) originated primarily for use in surgical planning, their application now extends well beyond this purpose. In this review, we describe an increasingly wide range of modeling applications aimed at uncovering fundamental mechanisms of disease progression and development, performing model-guided design, and generating testable hypotheses to drive targeted experiments. Increasingly, models are incorporating multiple physical processes spanning a wide range of time and length scales in the heart and vasculature. With these expanded capabilities, clinical adoption of patient-specific modeling in congenital and acquired cardiovascular disease is also increasing, impacting clinical care and treatment decisions in complex congenital heart disease, coronary artery disease, vascular surgery, pulmonary artery disease, and medical device design. In support of these efforts, we discuss recent advances in modeling methodology, which are most impactful when driven by clinical needs. We describe pivotal recent developments in image processing, fluid-structure interaction, modeling under uncertainty, and reduced order modeling to enable simulations in clinically relevant timeframes. In all these areas, we argue that traditional CFD alone is insufficient to tackle increasingly complex clinical and biological problems across scales and systems. Rather, CFD should be coupled with appropriate multiscale biological, physical, and physiological models needed to produce comprehensive, impactful models of mechanobiological systems and complex clinical scenarios. With this perspective, we finally outline open problems and future challenges in the field.
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Affiliation(s)
- Erica L. Schwarz
- Departments of Pediatrics and Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Luca Pegolotti
- Departments of Pediatrics and Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Martin R. Pfaller
- Departments of Pediatrics and Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Alison L. Marsden
- Departments of Pediatrics and Bioengineering, Stanford University, Stanford, California 94305, USA
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Das A, Hameed M, Prather R, Farias M, Divo E, Kassab A, Nykanen D, DeCampli W. In-Silico and In-Vitro Analysis of the Novel Hybrid Comprehensive Stage II Operation for Single Ventricle Circulation. Bioengineering (Basel) 2023; 10:bioengineering10020135. [PMID: 36829630 PMCID: PMC9952694 DOI: 10.3390/bioengineering10020135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 12/22/2022] [Accepted: 01/05/2023] [Indexed: 01/20/2023] Open
Abstract
Single ventricle (SV) anomalies account for one-fourth of all congenital heart disease cases. The existing palliative treatment for this anomaly achieves a survival rate of only 50%. To reduce the trauma associated with surgical management, the hybrid comprehensive stage II (HCSII) operation was designed as an alternative for a select subset of SV patients with the adequate antegrade aortic flow. This study aims to provide better insight into the hemodynamics of HCSII patients utilizing a multiscale Computational Fluid Dynamics (CFD) model and a mock flow loop (MFL). Both 3D-0D loosely coupled CFD and MFL models have been tuned to match baseline hemodynamic parameters obtained from patient-specific catheterization data. The hemodynamic findings from clinical data closely match the in-vitro and in-silico measurements and show a strong correlation (r = 0.9). The geometrical modification applied to the models had little effect on the oxygen delivery. Similarly, the particle residence time study reveals that particles injected in the main pulmonary artery (MPA) have successfully ejected within one cardiac cycle, and no pathological flows were observed.
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Affiliation(s)
- Arka Das
- Department of Mechanical Engineering, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, USA
- Correspondence: ; Tel.: +1-386-241-1457
| | - Marwan Hameed
- Department of Mechanical Engineering, American University of Bahrain, Riffa 942, Bahrain
| | - Ray Prather
- Department of Mechanical Engineering, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, USA
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA
- The Heart Center at Orlando Health Arnold Palmer Hospital for Children, Orlando, FL 32806, USA
| | - Michael Farias
- The Heart Center at Orlando Health Arnold Palmer Hospital for Children, Orlando, FL 32806, USA
- Department of Clinical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
| | - Eduardo Divo
- Department of Mechanical Engineering, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, USA
| | - Alain Kassab
- Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - David Nykanen
- The Heart Center at Orlando Health Arnold Palmer Hospital for Children, Orlando, FL 32806, USA
- Department of Clinical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
| | - William DeCampli
- The Heart Center at Orlando Health Arnold Palmer Hospital for Children, Orlando, FL 32806, USA
- Department of Clinical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
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4
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Liu X, Aslan S, Kim B, Warburton L, Jackson D, Muhuri A, Subramanian A, Mass P, Cleveland V, Loke YH, Hibino N, Olivieri L, Krieger A. Computational Fontan Analysis: Preserving Accuracy While Expediting Workflow. World J Pediatr Congenit Heart Surg 2022; 13:293-301. [PMID: 35446218 DOI: 10.1177/21501351211073619] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Background: Postoperative outcomes of the Fontan operation have been linked to geometry of the cavopulmonary pathway, including graft shape after implantation. Computational fluid dynamics (CFD) simulations are used to explore different surgical options. The objective of this study is to perform a systematic in vitro validation for investigating the accuracy and efficiency of CFD simulation to predict Fontan hemodynamics. Methods: CFD simulations were performed to measure indexed power loss (iPL) and hepatic flow distribution (HFD) in 10 patient-specific Fontan models, with varying mesh and numerical solvers. The results were compared with a novel in vitro flow loop setup with 3D printed Fontan models. A high-resolution differential pressure sensor was used to measure the pressure drop for validating iPL predictions. Microparticles with particle filtering system were used to measure HFD. The computational time was measured for a representative Fontan model with different mesh sizes and numerical solvers. Results: When compared to in vitro setup, variations in CFD mesh sizes had significant effect on HFD (P = .0002) but no significant impact on iPL (P = .069). Numerical solvers had no significant impact in both iPL (P = .50) and HFD (P = .55). A transient solver with 0.5 mm mesh size requires computational time 100 times more than a steady solver with 2.5 mm mesh size to generate similar results. Conclusions: The predictive value of CFD for Fontan planning can be validated against an in vitro flow loop. The prediction accuracy can be affected by the mesh size, model shape complexity, and flow competition.
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Affiliation(s)
- Xiaolong Liu
- Department of Mechanical Engineering, 1466Johns Hopkins University, Baltimore, MD, USA.,Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Seda Aslan
- Department of Mechanical Engineering, 1466Johns Hopkins University, Baltimore, MD, USA.,Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Byeol Kim
- Department of Mechanical Engineering, 1466Johns Hopkins University, Baltimore, MD, USA.,Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Linnea Warburton
- Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Derrick Jackson
- Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Abir Muhuri
- Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Akshay Subramanian
- Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
| | - Paige Mass
- Sheikh Zayed Institute for Pediatric Surgical Innovation, 8404Children's National Medical Center, Washington, DC, USA
| | - Vincent Cleveland
- Sheikh Zayed Institute for Pediatric Surgical Innovation, 8404Children's National Medical Center, Washington, DC, USA
| | - Yue-Hin Loke
- 8404Division of Cardiology, Children's National Medical Center, Washington, DC, USA
| | - Narutoshi Hibino
- 2462Department of Cardiac Surgery, University of Chicago/21880Advocate Children's Hospital, Chicago, IL, USA
| | - Laura Olivieri
- Sheikh Zayed Institute for Pediatric Surgical Innovation, 8404Children's National Medical Center, Washington, DC, USA.,8404Division of Cardiology, Children's National Medical Center, Washington, DC, USA
| | - Axel Krieger
- Department of Mechanical Engineering, 1466Johns Hopkins University, Baltimore, MD, USA.,Department of Mechanical Engineering, 1068University of Maryland, College Park, MD, USA
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Morphometrics of the Spinal Cord and Surrounding Structures in Alligator mississippiensis. BIOLOGY 2022; 11:biology11040514. [PMID: 35453713 PMCID: PMC9024830 DOI: 10.3390/biology11040514] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/22/2022] [Accepted: 03/24/2022] [Indexed: 02/04/2023]
Abstract
Simple Summary Morphometric analysis of the spinal cord and surrounding tissue of the American alligator (Alligator mississippiensis) reveals that there are four significantly discrete regions; cervical, thoracic, lumbar, and caudal. Crocodylians, unlike mammals, have a caudal spinal cord that extends throughout the length of their tail (which accounts for roughly 50% of their total body length). Alligator mississippiensis has one of the largest ranges of body sizes among terrestrial vertebrates, this study documents how the different spinal structures change with increasing body size. Though most of the structures exhibit slightly positive allometry, a few exhibit slightly negative allometry; these differences mean that there are significant relational changes as hatchlings grow into large adults. This study provides the first documentation that A. mississippiensis has an expansive subdural space, a lumbar cistern, at the pelvis. Abstract Understanding the fluid dynamics of the cerebrospinal fluid requires a quantitative description of the spaces in which it flows, including the spinal cord and surrounding meninges. The morphometrics of the spinal cord and surrounding tissues were studied in specimens of the American alligator (Alligator mississippiensis) ranging from hatchlings through adults. Within any size class of alligators (i.e., hatchlings), along the axial length there are significant differences in the size of the spinal cord, meninges, and vertebral canal; these differences can be used to define discrete cervical, thoracic, lumbar and caudal regions. When compared across the range of body sizes in Alligator, every structure in each spinal region had a distinctive growth rate; thus, the physical arrangements between the structures changed as the alligator grew. The combination of regional differentiation and differential growth rates was particularly apparent in the lumbar meninges where a unique form of lumbar cistern could be identified and shown to decrease in relative size as the alligator ages. This analysis of the spinal cord and surrounding tissues was undertaken to develop a data set that could be used for computational flow dynamics of the crocodilian cerebrospinal fluid, and also to assist in the analysis of fossil archosaurs.
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Itatani K, Sekine T, Yamagishi M, Maeda Y, Higashitani N, Miyazaki S, Matsuda J, Takehara Y. Hemodynamic Parameters for Cardiovascular System in 4D Flow MRI: Mathematical Definition and Clinical Applications. Magn Reson Med Sci 2022; 21:380-399. [PMID: 35173116 DOI: 10.2463/mrms.rev.2021-0097] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Blood flow imaging becomes an emerging trend in cardiology with the recent progress in computer technology. It not only visualizes colorful flow velocity streamlines but also quantifies the mechanical stress on cardiovascular structures; thus, it can provide the detailed inspections of the pathophysiology of diseases and predict the prognosis of cardiovascular functions. Clinical applications include the comprehensive assessment of hemodynamics and cardiac functions in echocardiography vector flow mapping (VFM), 4D flow MRI, and surgical planning as a simulation medicine in computational fluid dynamics (CFD).For evaluation of the hemodynamics, novel mathematically derived parameters obtained using measured velocity distributions are essential. Among them, the traditional and typical parameters are wall shear stress (WSS) and its related parameters. These parameters indicate the mechanical damages to endothelial cells, resulting in degenerative intimal change in vascular diseases. Apart from WSS, there are abundant parameters that describe the strength of the vortical and/or helical flow patterns. For instance, vorticity, enstrophy, and circulation indicate the rotating flow strength or power of 2D vortical flows. In addition, helicity, which is defined as the cross-linking number of the vortex filaments, indicates the 3D helical flow strength and adequately describes the turbulent flow in the aortic root in cases with complicated anatomies. For the description of turbulence caused by the diseased flow, there exist two types of parameters based on completely different concepts, namely: energy loss (EL) and turbulent kinetic energy (TKE). EL is the dissipated energy with blood viscosity and evaluates the cardiac workload related to the prognosis of heart failure. TKE describes the fluctuation in kinetic energy during turbulence, which describes the severity of the diseases that cause jet flow. These parameters are based on intuitive and clear physiological concepts, and are suitable for in vivo flow measurements using inner velocity profiles.
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Affiliation(s)
- Keiichi Itatani
- Department of Cardiovascular Surgery, Osaka City University.,Cardio Flow Design Inc
| | - Tetsuro Sekine
- Department of Radiology, Nippon Medical School Musashi Kosugi Hospital
| | - Masaaki Yamagishi
- Department of Pediatric Cardiovascular Surgery, Kyoto Prefectural University of Medicine
| | - Yoshinobu Maeda
- Department of Pediatric Cardiovascular Surgery, Kyoto Prefectural University of Medicine
| | - Norika Higashitani
- Cardio Flow Design Inc.,Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine
| | | | - Junya Matsuda
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Yasuo Takehara
- Department of Fundamental Development for Advanced Low Invasive Diagnostic Imaging, Nagoya university Graduate School of Medicine
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7
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Rigatelli G, Chiastra C, Pennati G, Dubini G, Migliavacca F, Zuin M. Applications of computational fluid dynamics to congenital heart diseases: a practical review for cardiovascular professionals. Expert Rev Cardiovasc Ther 2021; 19:907-916. [PMID: 34704881 DOI: 10.1080/14779072.2021.1999229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION The increased survival rate of patients with congenital heart disease (CHD) has made it likely that 70%-95% of infants with CHDs surviving into adulthood often require careful follow-up and (repeat) interventions. Patients with CHDs often have abnormal blood flow patterns, due to both primary cardiac defect and the consequent surgical or endovascular repair. AREA COVERED Computational fluid dynamics (CFD) alone or coupled with advanced imaging tools can assess blood flow patterns of CHDs to both understand their pathophysiology and anticipate the results of surgical or interventional repair. EXPERT OPINION CFD is a mathematical technique that quantifies and describes the characteristics of fluid flow using the laws of physics. Through dedicated software based on virtual reconstruction and simulation and patients' real data coming from computed tomography, magnetic resonance imaging, and 3/4 D-ultrasound, reconstruction of models of circulation of most CHD can be accomplished. CFD can provide insights about the pathophysiology of coronary artery anomalies, interatrial shunts, coarctation of the aorta and aortic bicuspid valve, tetralogy of Fallot and univentricular heart, with the capability in some cases of simulating different types of surgical or interventional repair and tailoring the treatment on the basis of these findings.
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Affiliation(s)
- Gianluca Rigatelli
- Cardiovascular Diagnosis and Endoluminal Interventions Unit, Rovigo General Hospital, Rovigo, Italy
| | - Claudio Chiastra
- PoliToBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Giancarlo Pennati
- Laboratory of Biological Structure Mechanics (Labs), Department of Chemistry, Materials and Chemical Engineering Giulio Natta, Politecnico di Milano, Milan, Italy
| | - Gabriele Dubini
- Laboratory of Biological Structure Mechanics (Labs), Department of Chemistry, Materials and Chemical Engineering Giulio Natta, Politecnico di Milano, Milan, Italy
| | - Francesco Migliavacca
- Laboratory of Biological Structure Mechanics (Labs), Department of Chemistry, Materials and Chemical Engineering Giulio Natta, Politecnico di Milano, Milan, Italy
| | - Marco Zuin
- Section of Internal and Cardiopulmonary Medicine, University of Ferrara, Ferrara, Italy
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8
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In-Vitro Validation of Self-Powered Fontan Circulation for Treatment of Single Ventricle Anomaly. FLUIDS 2021. [DOI: 10.3390/fluids6110401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Around 8% of all newborns with a Congenital Heart Defect (CHD) have only a single functioning ventricle. The Fontan operation has served as palliation for this anomaly for decades, but the surgery entails multiple complications, and the survival rate is less than 50% by adulthood. A rapidly testable novel alternative is proposed by creating a bifurcating graft, or Injection Jet Shunt (IJS), used to “entrain” the pulmonary flow and thus provide assistance while reducing the caval pressure. A dynamically scaled Mock Flow Loop (MFL) has been configured to validate this hypothesis. Three IJS nozzles of varying diameters 2, 3, and 4 mm with three aortic anastomosis angles and pulmonary vascular resistance (PVR) reduction have been tested to validate the hypothesis and optimize the caval pressure reduction. The MFL is based on a Lumped-Parameter Model (LPM) of a non-fenestrated Fontan circulation. The best outcome was achieved with the experimental testing of a 3 mm IJS by producing an average caval pressure reduction of more than 5 mmHg while maintaining the clinically acceptable pulmonary flow rate (Qp) to systemic flow rate (Qs) ratio of ~1.5. Furthermore, alteration of the PVR helped in achieving higher caval pressure reduction with the 3 mm IJS at the expense of an increase in Qp/Qs ratio.
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Schwarz EL, Kelly JM, Blum KM, Hor KN, Yates AR, Zbinden JC, Verma A, Lindsey SE, Ramachandra AB, Szafron JM, Humphrey JD, Shin'oka T, Marsden AL, Breuer CK. Hemodynamic performance of tissue-engineered vascular grafts in Fontan patients. NPJ Regen Med 2021; 6:38. [PMID: 34294733 PMCID: PMC8298568 DOI: 10.1038/s41536-021-00148-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 06/11/2021] [Indexed: 02/06/2023] Open
Abstract
In the field of congenital heart surgery, tissue-engineered vascular grafts (TEVGs) are a promising alternative to traditionally used synthetic grafts. Our group has pioneered the use of TEVGs as a conduit between the inferior vena cava and the pulmonary arteries in the Fontan operation. The natural history of graft remodeling and its effect on hemodynamic performance has not been well characterized. In this study, we provide a detailed analysis of the first U.S. clinical trial evaluating TEVGs in the treatment of congenital heart disease. We show two distinct phases of graft remodeling: an early phase distinguished by rapid changes in graft geometry and a second phase of sustained growth and decreased graft stiffness. Using clinically informed and patient-specific computational fluid dynamics (CFD) simulations, we demonstrate how changes to TEVG geometry, thickness, and stiffness affect patient hemodynamics. We show that metrics of patient hemodynamics remain within normal ranges despite clinically observed levels of graft narrowing. These insights strengthen the continued clinical evaluation of this technology while supporting recent indications that reversible graft narrowing can be well tolerated, thus suggesting caution before intervening clinically.
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Affiliation(s)
- Erica L Schwarz
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
| | - John M Kelly
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- The Heart Center, Nationwide Children's Hospital, Columbus, OH, USA
| | - Kevin M Blum
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Kan N Hor
- The Heart Center, Nationwide Children's Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Andrew R Yates
- The Heart Center, Nationwide Children's Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Jacob C Zbinden
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Aekaansh Verma
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Stephanie E Lindsey
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Department of Pediatrics, Stanford University, Stanford, CA, USA
| | | | - Jason M Szafron
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Toshiharu Shin'oka
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- The Heart Center, Nationwide Children's Hospital, Columbus, OH, USA
- Department of Cardiothoracic Surgery, Nationwide Children's Hospital, Columbus, OH, USA
| | - Alison L Marsden
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Department of Pediatrics, Stanford University, Stanford, CA, USA
| | - Christopher K Breuer
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Department of Surgery, Nationwide Children's Hospital, Columbus, OH, USA
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10
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Engineering Perspective on Cardiovascular Simulations of Fontan Hemodynamics: Where Do We Stand with a Look Towards Clinical Application. Cardiovasc Eng Technol 2021; 12:618-630. [PMID: 34114202 DOI: 10.1007/s13239-021-00541-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 04/30/2021] [Indexed: 01/02/2023]
Abstract
BACKGROUND Cardiovascular simulations for patients with single ventricles undergoing the Fontan procedure can assess patient-specific hemodynamics, explore surgical advances, and develop personalized strategies for surgery and patient care. These simulations have not yet been broadly accepted as a routine clinical tool owing to a number of limitations. Numerous approaches have been explored to seek innovative solutions for improving methodologies and eliminating these limitations. PURPOSE This article first reviews the current state of cardiovascular simulations of Fontan hemodynamics. Then, it will discuss the technical progress of Fontan simulations with the emphasis of its clinical impact, noting that substantial improvements have been made in the considerations of patient-specific anatomy, flow, and blood rheology. The article concludes with insights into potential future directions involving clinical validation, uncertainty quantification, and computational efficiency. The advancements in these aspects could promote the clinical usage of Fontan simulations, facilitating its integration into routine clinical practice.
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A Tribute to Ajit Yoganathan's Cardiovascular Fluid Mechanics Lab: A Survey of Its Contributions to Our Understanding of the Physiology and Management of Single-Ventricle Patients. Cardiovasc Eng Technol 2021; 12:631-639. [PMID: 34018153 DOI: 10.1007/s13239-021-00540-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 04/30/2021] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Among patients with congenital heart disease, those born with only a single working ventricle represent a particularly complex sub-population, typically requiring multiple surgeries and suffering from high levels of mortality and morbidity. Their cardiac care is complex and has evolved considerably since surgical palliation was first introduced more than 50 years ago. Improvements in treatment have been driven both by growing clinical experience and by knowledge gained through experimental and computational studies of blood flow in these patients. The Cardiovascular Fluid Mechanics Lab at the Georgia Institute of Technology, founded 30 years ago by Dr. Ajit Yoganathan, has pioneered work in this field. METHODS In this review, key contributions of Dr. Yoganathan's Cardiovascular Fluid Dynamics Lab are surveyed, including experimental flow loop studies as well as computational fluid dynamics analyses that address many of the critical challenges that cardiologists and surgeons face in treating these patients, including how to reconstruct cardiovascular anatomy to minimize power loss, balance blood flow distribution at key bifurcation points, and avoid other unfavorable hemodynamic conditions. CONCLUSIONS Among many contributions in this field, work from the Cardiovascular Fluid Mechanics Lab has led to novel medical devices and patient-specific computational modeling workflows and software tools. These key contributions from this group have enhanced our understanding of the physiology and management of single-ventricle patients.
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12
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Ordoñez MV, Biglino G, Caputo M, Curtis SL. Pregnancy in the FONTAN palliation: physiology, management and new insights from bioengineering. JOURNAL OF CONGENITAL CARDIOLOGY 2021. [DOI: 10.1186/s40949-021-00058-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractFontan palliation for the single ventricle results in a challenging and delicate physiological state. At rest, the body adapts to a low cardiac output and high systemic venous pressure. However, when physiological demands increase, such as in the case of exercise or pregnancy, this delicate physiology struggles to adapt due to the inability of the heart to pump blood into the lungs and the consequent lack of augmentation of the cardiac output.Due to the advances in paediatric cardiology, surgery and intensive care, today most patients born with congenital heart disease reach adulthood. Consequently, many women with a Fontan circulation are becoming pregnant and so far data suggest that, although maternal risk is not high, the outcomes are poor for the foetus. Little is known about the reasons for this disparity and how the Fontan circulation adapts to the physiological demands of pregnancy.Here we review current knowledge about pregnancy in Fontan patients and explore the potential role of computational modelling as a means of better understanding this complex physiology in order to potentially improve outcomes, particularly for the foetus.
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Hsia TY. Invited Commentary: Form and Function in Surgical Planning. World J Pediatr Congenit Heart Surg 2021; 12:244-245. [PMID: 33684006 DOI: 10.1177/2150135121990395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Tain-Yen Hsia
- Pediatric Cardiac Surgery, The Heart Center at 25102Arnold Palmer Hospital for Children, Orlando, FL, USA
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Wei ZA, Ratnayaka K, Si B, Singh-Gryzbon S, Cetatoiu MA, Fogel MA, Slesnick T, Yoganathan AP, Nigro JJ. An Anterior Anastomosis for the Modified Fontan Connection: A Hemodynamic Analysis. Semin Thorac Cardiovasc Surg 2021; 33:816-823. [PMID: 33662555 DOI: 10.1053/j.semtcvs.2021.01.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 01/05/2021] [Indexed: 12/25/2022]
Abstract
This hemodynamic feasibility study examined total cavopulmonary connection (TCPC) designs connecting the extracardiac conduit to the anterior surface of pulmonary arteries (PAs) or superior vena cava (SVC) rather than to the inferior PA surface (traditional TCPC). The study involved twenty-five consecutive Fontan patients meeting inclusion criteria from a single institution. A virtual surgical platform mimicked the completed traditional TCPC and generated three anterior anastomosis designs: Anterior-PA, Middle-SVC, and SVC-Inn (Inn: innominate vein). Hemodynamic performance of anterior anastomosis designs was compared with the traditional TCPC regarding indexed power loss (iPL) and hepatic flow distribution (HFD). Compared to the traditional TCPC, the Anterior-PA design produces a similar iPL. The Middle-SVC design is also similar, though the iPL difference is positively correlated with the anastomosing height. The SVC-Inn design had significantly more iPL. The three anterior anastomosis designs did not have a significant difference in HFD (from traditional TCPC). Pulmonary flow distribution (PFD) has a stronger correlation with HFD from the anterior anastomosis designs than the traditional TCPC. This hemodynamic feasibility study examined anterior anastomosis, extracardiac TCPC designs that may offer surgeons clinical dexterity. The Anterior-PA design may be equivalent to the traditional TCPC. Fontan extracardiac conduit anastomosis just superior to the PAs (Middle-SVC) also preserves hemodynamic performance and avoids direct PA anastomosis. These designs could simplify surgical Fontan completion, and may particularly benefit patients requiring surgical dissection, having atypical PA orientation, or after PA stent angioplasty.
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Affiliation(s)
- Zhenglun Alan Wei
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia; Department of Biomedical Engineering, University of Massachusetts Lowell, Lowell, Massachusetts
| | - Kanishka Ratnayaka
- Division of Pediatric Cardiology, Rady Children's Hospital and UC San Diego School of Medicine, San Diego, California
| | - Biao Si
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia
| | - Shelly Singh-Gryzbon
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia
| | | | - Mark A Fogel
- Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Timothy Slesnick
- Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, Georgia
| | - Ajit P Yoganathan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.
| | - John J Nigro
- Division of Cardiovascular Surgery, Rady Children's Hospital and UC San Diego School of Medicine, San Diego, California
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Daley M, d'Udekem Y. The optimal Fontan operation: Lateral tunnel or extracardiac conduit? J Thorac Cardiovasc Surg 2020; 162:1825-1834. [PMID: 33581907 DOI: 10.1016/j.jtcvs.2020.11.179] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/09/2020] [Accepted: 11/26/2020] [Indexed: 01/14/2023]
Affiliation(s)
- Michael Daley
- Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, Australia; Murdoch Children's Research Institute, Melbourne, Australia
| | - Yves d'Udekem
- Department of Paediatrics, The University of Melbourne, Melbourne, Australia; Murdoch Children's Research Institute, Melbourne, Australia; Division of Cardiac Surgery, Children's National Hospital, Washington, DC.
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Optimized Computed Tomography Angiography Protocol for the Evaluation of Thrombus in Patients with Fontan Anatomy. Pediatr Cardiol 2020; 41:1601-1607. [PMID: 32785745 DOI: 10.1007/s00246-020-02417-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 07/18/2020] [Indexed: 10/23/2022]
Abstract
The Fontan procedure is the final stage in the palliative surgical approach to patients with single-ventricle physiology. These patients have an increased risk for thromboembolic disease in the Fontan circuit, which can be evaluated by chest computed tomography angiography (CTA) in acute settings. However, false-positive results are common secondary to unusual streaming patterns in the Fontan circuit. A biphasic CTA protocol was evaluated for the capability to clearly identify structures of the Fontan circuit that are critical for the evaluation of thromboembolic disease. The study was a retrospective chart review of Fontan patients with a chest CTA scan obtained between 2011 and 2017. Two pediatric cardiologists with additional training in cardiac CT imaging independently reviewed each CTA and awarded one point for each of 5 Fontan circuit structures clearly identified resulting in a score range of 0-5. A score of 0-2 considered not capable, 3-4 partially capable, and 5 capable to clearly identify critical structures of the Fontan circuit. During the study period, 46 CTA scans were performed on 21 patients. Of the CTA scans using a biphasic protocol, 62.5% (10/16) were considered capable to clearly identify all 5 critical structures of the Fontan circuit vs 27% (8/30) of the CTA scans using a monophasic protocol (p = 0.027). Overall our results suggest that the single-site biphasic CTA protocol has greater diagnostic capability to detect the presence of Fontan thromboembolic disease when compared to the more traditional monophasic CTA protocol. Future prospective studies are needed to confirm these findings.
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McHugo VS, Nolke L, Delassus P, MaCarthy E, McMahon CJ, Morris L. The impact of compliance on Stage 2 uni-ventricular heart circulation: An experimental assessment of the Bidirectional Glenn. Med Eng Phys 2020; 84:184-192. [PMID: 32977917 DOI: 10.1016/j.medengphy.2020.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 03/11/2020] [Accepted: 07/13/2020] [Indexed: 11/30/2022]
Abstract
The Bidirectional Glenn (BDG) or cavopulmonary connection is typically undertaken to volume unload the single ventricle in an effort to preserve ventricular and atrioventricular valve function. The geometry of this surgical palliation has been shown to influence the fluid energy loss as well as the distribution of flow that enters through the superior vena cava. In-vitro and in-silico studies to date have been performed on rigid wall models, while this investigation looks at the impact of flexible thin walled models versus rigid walls. Rigid and compliant models of two patient-specific Glenn geometries were fabricated and tested under various flow conditions, within a biosimulator capable of replicating patient specific flow conditions. It was found that the compliant models exhibit greater levels of energy loss compared to the rigid models. Along with these findings greater levels of turbulence was found in both compliant models compared to their rigid counterparts under ultrasound examinations. This shows that vessel compliance has a significant impact on the hemodynamics within hypoplastic left heart syndrome.
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Affiliation(s)
- V S McHugo
- Department of Mechanical and Industrial Engineering (GMIT), Galway Medical Technology Centre, Ireland.
| | - L Nolke
- Department of Pediatric Cardiology Our Lady's Children's Hospital Crumlin, Dublin, Ireland; University College Dublin School of Medicine, Belfield, Dublin, Ireland
| | - P Delassus
- Department of Mechanical and Industrial Engineering (GMIT), Galway Medical Technology Centre, Ireland
| | - E MaCarthy
- Department of Mechanical and Industrial Engineering (GMIT), Galway Medical Technology Centre, Ireland
| | - C J McMahon
- Department of Pediatric Cardiology Our Lady's Children's Hospital Crumlin, Dublin, Ireland; University College Dublin School of Medicine, Belfield, Dublin, Ireland.
| | - L Morris
- Department of Mechanical and Industrial Engineering (GMIT), Galway Medical Technology Centre, Ireland.
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Gerrah R, Haller SJ. Computational fluid dynamics: a primer for congenital heart disease clinicians. Asian Cardiovasc Thorac Ann 2020; 28:520-532. [PMID: 32878458 DOI: 10.1177/0218492320957163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Computational fluid dynamics has become an important tool for studying blood flow dynamics. As an in-silico collection of methods, computational fluid dynamics is noninvasive and provides numerical values for the most important parameters of blood flow, such as velocity and pressure that are crucial in hemodynamic studies. In this primer, we briefly explain the basic theory and workflow of the two most commonly applied computational fluid dynamics techniques used in the congenital heart disease literature: the finite element method and the finite volume method. We define important terminology and include specific examples of how using these methods can answer important clinical questions in congenital cardiac surgery planning and perioperative patient management.
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Affiliation(s)
- Rabin Gerrah
- Stanford University, Samaritan Cardiovascular Surgery, Corvallis, OR, USA
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McHugo S, Nolke L, Delassus P, MacCarthy E, Morris L, McMahon CJ. An in-vitro evaluation of the flow haemodynamic performance of Gore-Tex extracardiac conduits for univentricular circulation. J Cardiothorac Surg 2020; 15:235. [PMID: 32878643 PMCID: PMC7466829 DOI: 10.1186/s13019-020-01269-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 08/24/2020] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE(S) The Fontan procedure is a common palliative intervention for sufferers of single ventricle congenital heart defects that results in an anastomosis of the venous return to the pulmonary arteries called the total cavopulmonary connection (TCPC). In patients with palliated single ventricular heart defects, the Fontan circulation passively directs systemic venous return to the pulmonary circulation in the absence of a functional sub-pulmonary ventricle. Therefore, the Fontan circulation is highly dependent on favourable flow and energetics, and minimal energy loss is of great importance. The majority of in vitro studies, to date, employ a rigid TCPC model. Recently, few studies have incorporated flexible TCPC models, without the inclusion of commercially available conduits used in these surgical scenarios. METHOD The methodology set out in this study successfully utilizes patient-specific phantoms along with the corresponding flowrate waveforms to characterise the flow haemodynamic performance of extracardiac Gore-Tex conduits. This was achieved by comparing a rigid and flexible TCPC models against a flexible model with an integrated Gore-Tex conduit. RESULTS The flexible model with the integrated Gore-Tex graft exhibited greater levels of energy losses when compared to the rigid walled model. With this, the flow fields showed greater levels of turbulence in the complaint and Gore-Tex models compared to the rigid model under ultrasound analysis. CONCLUSION This study shows that vessel compliance along with the incorporation of Gore-Tex extracardiac conduits have significant impact on the flow haemodynamics in a patient-specific surgical scenario.
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Affiliation(s)
- Shane McHugo
- Galway Medical Technology Centre, Department of Mechanical and Industrial Engineering (GMIT), Galway, Ireland
| | - Lars Nolke
- Department of Cardiothoracic Surgery, Children's Health Ireland, Crumlin, Dublin 12, Ireland
| | - Patrick Delassus
- Galway Medical Technology Centre, Department of Mechanical and Industrial Engineering (GMIT), Galway, Ireland
| | - Eugene MacCarthy
- Galway Medical Technology Centre, Department of Mechanical and Industrial Engineering (GMIT), Galway, Ireland
| | - Liam Morris
- Galway Medical Technology Centre, Department of Mechanical and Industrial Engineering (GMIT), Galway, Ireland
| | - Colin Joseph McMahon
- Department of Pediatric Cardiology Children's Health Ireland, Crumlin, Dublin 12, Ireland.
- University College Dublin School of Medicine, Belfield, Dublin 4, Ireland.
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Hsia TY, Conover T, Figliola R. Computational Modeling to Support Surgical Decision Making in Single Ventricle Physiology. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu 2020; 23:2-10. [PMID: 32354542 DOI: 10.1053/j.pcsu.2020.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 11/11/2022]
Abstract
Many of the advances in congenital heart surgery were built upon lessons and insights gained from model simulations. While animal and mock-circuit models have historically been the main arena to test new operative techniques and concepts, the recognition that complex cardiovascular anatomy and circulation can be modeled mathematically ushered a new era of collaboration between surgeons and engineers. In 1996, the computational age in congenital heart surgery began when investigators in London and Milan tapped the power of the computer to simulate the Fontan procedure and introduced operative improvements. Since then, computational modeling has led to numerous contributions in congenial heart surgery as continuing sophistication and advances in numerical and imaging methods furthered the ability to refine anatomic and physiologic details. Idealized generic models have given way to precise patient-specific simulations of the 3-dimensional anatomy, reconstructed circulation, affected hemodynamics, and altered physiology. Tools to perform virtual surgery, and predict flow dynamic and circulatory results, have been developed for some of the most complex defects, such as those requiring single ventricle palliation. In today's quest for personalized medicine and precision care, computational modeling's role to assist surgical planning in complex congenital heart surgery will continue to grow and evolve. With ever closer collaboration between surgeons and engineers, and clear understanding of modeling limitations, computational simulations can be a valuable adjunct to support preoperative surgical decision making.
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Affiliation(s)
- Tain-Yen Hsia
- Pediatric Cardiac Surgery, Yale School of Medicine, New Haven, Connecticut.
| | - Timothy Conover
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina
| | - Richard Figliola
- Department of Mechanical Engineering, Clemson University, Clemson, South Carolina
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Hsia TY. Commentary: Man versus machine: Whose side are you on? J Thorac Cardiovasc Surg 2020; 160:216-217. [PMID: 32127203 DOI: 10.1016/j.jtcvs.2020.01.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Tain-Yen Hsia
- Pediatric Cardiac Surgery, Yale New Haven Children's Hospital, Yale School of Medicine, New Haven, Conn.
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Kainuma A, Akiyama K, Naito Y, Hayase K, Hongu H, Itatani K, Yamagishi M, Sawa T. Energetic performance index improvement after Glenn and Damus-Kaye-Stansel procedure using vector flow mapping analysis: a case report. JA Clin Rep 2020; 6:5. [PMID: 32026035 PMCID: PMC6973790 DOI: 10.1186/s40981-020-0312-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/14/2020] [Indexed: 11/30/2022] Open
Abstract
Background Echocardiography vector flow mapping can assess dynamic flow to treat congenital heart diseases. We evaluated intracardiac flow, energy loss, left ventricular output kinetic energy, and energetic performance index using vector flow mapping during Glenn and Damus-Kaye-Stansel procedures in order to assess the efficacy of the surgery. Case presentation A 9-month-old boy underwent Glenn and Damus-Kaye-Stansel procedures. The energy loss depends on the left ventricular preload; therefore, energy loss decreased after the Glenn procedure. After the Damus-Kaye-Stansel procedure, the kinetic energy would increase owing to the integrated systemic outflow; however, in our case, kinetic energy decreased, which was potentially explained by the fact that kinetic energy also depends on the left ventricular preload. After the Glenn and Damus-Kaye-Stansel procedures, we detected an improvement in energetic performance index, indicating that the cardiac workload improved as well. Conclusion We revealed the efficiency of the Glenn and Damus-Kaye-Stansel procedures using vector flow mapping.
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Affiliation(s)
- Atsushi Kainuma
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan.
| | - Koichi Akiyama
- Department of Anesthesiology, Yodogawa Christian Hospital, 1 Chome-7-50, Kunijima, Higashiyodogawa Ward, Osaka, 533-0024, Japan
| | - Yoshifumi Naito
- Department of Anesthesia and Perioperative care, University of California San Francisco, 505 Parnassus Ave, San Francisco, CA, 94143, USA
| | - Kazuma Hayase
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan
| | - Hisayuki Hongu
- Department of Pediatric Cardiovascular Surgery, Children's Medical Center, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan
| | - Keiichi Itatani
- Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan
| | - Masaaki Yamagishi
- Department of Pediatric Cardiovascular Surgery, Children's Medical Center, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan
| | - Teiji Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyoku, Kyoto, 602-8566, Japan
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Acuna A, Berman AG, Damen FW, Meyers BA, Adelsperger AR, Bayer KC, Brindise MC, Bungart B, Kiel AM, Morrison RA, Muskat JC, Wasilczuk KM, Wen Y, Zhang J, Zito P, Goergen CJ. Computational Fluid Dynamics of Vascular Disease in Animal Models. J Biomech Eng 2019; 140:2676341. [PMID: 29570754 DOI: 10.1115/1.4039678] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Indexed: 12/19/2022]
Abstract
Recent applications of computational fluid dynamics (CFD) applied to the cardiovascular system have demonstrated its power in investigating the impact of hemodynamics on disease initiation, progression, and treatment outcomes. Flow metrics such as pressure distributions, wall shear stresses (WSS), and blood velocity profiles can be quantified to provide insight into observed pathologies, assist with surgical planning, or even predict disease progression. While numerous studies have performed simulations on clinical human patient data, it often lacks prediagnosis information and can be subject to large intersubject variability, limiting the generalizability of findings. Thus, animal models are often used to identify and manipulate specific factors contributing to vascular disease because they provide a more controlled environment. In this review, we explore the use of CFD in animal models in recent studies to investigate the initiating mechanisms, progression, and intervention effects of various vascular diseases. The first section provides a brief overview of the CFD theory and tools that are commonly used to study blood flow. The following sections are separated by anatomical region, with the abdominal, thoracic, and cerebral areas specifically highlighted. We discuss the associated benefits and obstacles to performing CFD modeling in each location. Finally, we highlight animal CFD studies focusing on common surgical treatments, including arteriovenous fistulas (AVF) and pulmonary artery grafts. The studies included in this review demonstrate the value of combining CFD with animal imaging and should encourage further research to optimize and expand upon these techniques for the study of vascular disease.
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Affiliation(s)
- Andrea Acuna
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Alycia G Berman
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Frederick W Damen
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Brett A Meyers
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Amelia R Adelsperger
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Kelsey C Bayer
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Melissa C Brindise
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Brittani Bungart
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Alexander M Kiel
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Rachel A Morrison
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Joseph C Muskat
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Kelsey M Wasilczuk
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Yi Wen
- Department of Agricultural and Biological Engineering, Purdue University, 225 South University Street, West Lafayette, IN 47907 e-mail:
| | - Jiacheng Zhang
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907 e-mail:
| | - Patrick Zito
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
| | - Craig J Goergen
- ASME Membership Bioengineering Division, Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN 47907 e-mail:
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24
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Kung E, Corsini C, Marsden A, Vignon-Clementel I, Pennati G, Figliola R, Hsia TY. Multiscale Modeling of Superior Cavopulmonary Circulation: Hemi-Fontan and Bidirectional Glenn Are Equivalent. Semin Thorac Cardiovasc Surg 2019; 32:883-892. [PMID: 31520732 DOI: 10.1053/j.semtcvs.2019.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 09/04/2019] [Indexed: 11/11/2022]
Abstract
Superior cavopulmonary circulation (SCPC) can be achieved by either the Hemi-Fontan (hF) or Bidirectional Glenn (bG) connection. Debate remains as to which results in best hemodynamic results. Adopting patient-specific multiscale computational modeling, we examined both the local dynamics and global physiology to determine if surgical choice can lead to different hemodynamic outcomes. Six patients (age: 3-6 months) underwent cardiac magnetic resonance imaging and catheterization prior to SCPC surgery. For each patient: (1) a finite 3-dimensional (3D) volume model of the preoperative anatomy was constructed to include detailed definition of the distal branch pulmonary arteries, (2) virtual hF and bG operations were performed to create 2 SCPC 3D models, and (3) a specific lumped network representing each patient's entire cardiovascular circulation was developed from clinical data. Using a previously validated multiscale algorithm that couples the 3D models with lumped network, both local flow dynamics, that is, power loss, and global systemic physiology can be quantified. In 2 patients whose preoperative imaging demonstrated significant left pulmonary artery (LPA) stenosis, we performed virtual pulmonary arterioplasty to assess its effect. In one patient, the hF model showed higher power loss (107%) than the bG, while in 3, the power losses were higher in the bG models (18-35%). In the remaining 2 patients, the power loss differences were minor. Despite these variations, for all patients, there were no significant differences between the hF and bG models in hemodynamic or physiological outcomes, including cardiac output, superior vena cava pressure, right-left pulmonary flow distribution, and systemic oxygen delivery. In the 2 patients with LPA stenosis, arterioplasty led to better LPA flow (5-8%) while halving the power loss, but without important improvements in SVC pressure or cardiac output. Despite power loss differences, both hF and bG result in similar SCPC hemodynamics and physiology outcome. This suggests that for SCPC, the pre-existing patient-specific physiology and condition, such as pulmonary vascular resistance, are more deterministic in the hemodynamic performance than the type of surgical palliation. Multiscale modeling can be a decision-assist tool to assess whether an extensive LPA reconstruction is needed at the time of SCPC for LPA stenosis.
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Affiliation(s)
- Ethan Kung
- Clemson University, Clemson, South Carolina
| | | | | | - Irene Vignon-Clementel
- National Institute for Research in Computer Science and Automation (INRIA), Paris, France
| | | | | | - Tain-Yen Hsia
- Pediatric Cardiac Surgery, Yale New Haven Children's Hospital, New Haven, Connecticut.
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Rychik J, Atz AM, Celermajer DS, Deal BJ, Gatzoulis MA, Gewillig MH, Hsia TY, Hsu DT, Kovacs AH, McCrindle BW, Newburger JW, Pike NA, Rodefeld M, Rosenthal DN, Schumacher KR, Marino BS, Stout K, Veldtman G, Younoszai AK, d'Udekem Y. Evaluation and Management of the Child and Adult With Fontan Circulation: A Scientific Statement From the American Heart Association. Circulation 2019; 140:e234-e284. [PMID: 31256636 DOI: 10.1161/cir.0000000000000696] [Citation(s) in RCA: 393] [Impact Index Per Article: 78.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
It has been 50 years since Francis Fontan pioneered the operation that today bears his name. Initially designed for patients with tricuspid atresia, this procedure is now offered for a vast array of congenital cardiac lesions when a circulation with 2 ventricles cannot be achieved. As a result of technical advances and improvements in patient selection and perioperative management, survival has steadily increased, and it is estimated that patients operated on today may hope for a 30-year survival of >80%. Up to 70 000 patients may be alive worldwide today with Fontan circulation, and this population is expected to double in the next 20 years. In the absence of a subpulmonary ventricle, Fontan circulation is characterized by chronically elevated systemic venous pressures and decreased cardiac output. The addition of this acquired abnormal circulation to innate abnormalities associated with single-ventricle congenital heart disease exposes these patients to a variety of complications. Circulatory failure, ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, protein-losing enteropathy, and plastic bronchitis are potential complications of the Fontan circulation. Abnormalities in body composition, bone structure, and growth have been detected. Liver fibrosis and renal dysfunction are common and may progress over time. Cognitive, neuropsychological, and behavioral deficits are highly prevalent. As a testimony to the success of the current strategy of care, the proportion of adults with Fontan circulation is increasing. Healthcare providers are ill-prepared to tackle these challenges, as well as specific needs such as contraception and pregnancy in female patients. The role of therapies such as cardiovascular drugs to prevent and treat complications, heart transplantation, and mechanical circulatory support remains undetermined. There is a clear need for consensus on how best to follow up patients with Fontan circulation and to treat their complications. This American Heart Association statement summarizes the current state of knowledge on the Fontan circulation and its consequences. A proposed surveillance testing toolkit provides recommendations for a range of acceptable approaches to follow-up care for the patient with Fontan circulation. Gaps in knowledge and areas for future focus of investigation are highlighted, with the objective of laying the groundwork for creating a normal quality and duration of life for these unique individuals.
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Rijnberg FM, Hazekamp MG, Wentzel JJ, de Koning PJ, Westenberg JJ, Jongbloed MR, Blom NA, Roest AA. Energetics of Blood Flow in Cardiovascular Disease. Circulation 2018; 137:2393-2407. [DOI: 10.1161/circulationaha.117.033359] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | | | - Jolanda J. Wentzel
- Leiden University Medical Center, The Netherlands. Department of Biomechanical Engineering, Erasmus Medical Center, Rotterdam, The Netherlands (J.J.W.)
| | | | | | | | - Nico A. Blom
- Department of Pediatric Cardiology (N.A.B., A.A.W.R.)
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Trusty PM, Slesnick TC, Wei ZA, Rossignac J, Kanter KR, Fogel MA, Yoganathan AP. Fontan Surgical Planning: Previous Accomplishments, Current Challenges, and Future Directions. J Cardiovasc Transl Res 2018; 11:133-144. [PMID: 29340873 PMCID: PMC5910220 DOI: 10.1007/s12265-018-9786-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/05/2018] [Indexed: 11/29/2022]
Abstract
The ultimate goal of Fontan surgical planning is to provide additional insights into the clinical decision-making process. In its current state, surgical planning offers an accurate hemodynamic assessment of the pre-operative condition, provides anatomical constraints for potential surgical options, and produces decent post-operative predictions if boundary conditions are similar enough between the pre-operative and post-operative states. Moving forward, validation with post-operative data is a necessary step in order to assess the accuracy of surgical planning and determine which methodological improvements are needed. Future efforts to automate the surgical planning process will reduce the individual expertise needed and encourage use in the clinic by clinicians. As post-operative physiologic predictions improve, Fontan surgical planning will become an more effective tool to accurately model patient-specific hemodynamics.
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Affiliation(s)
- Phillip M Trusty
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Timothy C Slesnick
- Department of Pediatrics, Division of Cardiology, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Zhenglun Alan Wei
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- School of Life Science, Fudan University, Shanghai, China
| | - Jarek Rossignac
- School of Interactive Computing, Georgia Institute of Technology, Atlanta, GA, USA
| | - Kirk R Kanter
- Division of Cardiothoracic Surgery, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Mark A Fogel
- Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ajit P Yoganathan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
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Talwar S, Sankhyan L, Patel C, Sreenivas V, Choudhary SK, Airan B. Evaluation of differential pulmonary perfusion using 99mTc macroaggregated albumin after the Fontan procedure. Interact Cardiovasc Thorac Surg 2018; 26:651-659. [PMID: 29240900 DOI: 10.1093/icvts/ivx377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 10/30/2017] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES The Fontan procedure [total cavopulmonary connection (TCPC)] is the final palliation for patients with univentricular physiology. We studied differential perfusion ratio and percentage uptake of a radiotracer in different zones of each lung following TCPC. METHODS Between July 2015 and June 2017, 45 patients underwent 99mTc macroaggregated albumin lung perfusion scan at a mean follow-up period of 49.3 ± SD 26.1 days following TCPC. Differential perfusion ratio and percentage uptake of the radiotracer in the upper, middle and lower zones of each lung were calculated. RESULTS Post-foot injection [inferior vena cava (IVC) injection], preferential flow to the lungs was as follows: left lung (n = 13, 30.2%), right lung (n = 13, 30.2%) and uniformly to both lungs (n= 17, 39.6%). Post-arm injection [superior vena cava (SVC) injection], preferential flow to the lungs was as follows: left lung (n = 13, 30.2%), right lung (n = 22, 51.2%) and uniformly to both lungs (n= 8, 18.6%). The middle zone was perfused the most in both lungs. Total lower zone mean perfusion was higher than the upper zone following both SVC injection and IVC injection (34.1 ± SD 5.3% vs 17. ± SD 4.1% and 33 ± SD 5.0% vs 17.5 ± SD 4.1%, respectively). In patients with bilateral SVC, post-IVC injection, 6 (75%) patients had preferential flow to the right lung, whereas post-SVC injection, preferential flow to the left lung was visualized in 7 (87.5%) patients. CONCLUSIONS Following TCPC, IVC blood was distributed uniformly in both lungs. SVC blood preferentially perfused the right lung. The middle zone was perfused the most in both lungs.
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Affiliation(s)
- Sachin Talwar
- Department of Cardiothoracic and Vascular Surgery, Cardiothoracic Center, All India Institute of Medical Sciences, New Delhi, India
| | - Lakshmi Sankhyan
- Department of Cardiothoracic and Vascular Surgery, Cardiothoracic Center, All India Institute of Medical Sciences, New Delhi, India
| | - Chetan Patel
- Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
| | | | - Shiv Kumar Choudhary
- Department of Cardiothoracic and Vascular Surgery, Cardiothoracic Center, All India Institute of Medical Sciences, New Delhi, India
| | - Balram Airan
- Department of Cardiothoracic and Vascular Surgery, Cardiothoracic Center, All India Institute of Medical Sciences, New Delhi, India
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29
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Kong F, Kheyfets V, Finol E, Cai XC. An efficient parallel simulation of unsteady blood flows in patient-specific pulmonary artery. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2018; 34:e2952. [PMID: 29245182 DOI: 10.1002/cnm.2952] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/26/2017] [Accepted: 12/02/2017] [Indexed: 06/07/2023]
Abstract
Simulation of blood flows in the pulmonary artery provides some insight into certain diseases by examining the relationship between some continuum metrics, eg, the wall shear stress acting on the vascular endothelium, which responds to flow-induced mechanical forces by releasing vasodilators/constrictors. V. Kheyfets, in his previous work, studies numerically a patient-specific pulmonary circulation to show that decreasing wall shear stress is correlated with increasing pulmonary vascular impedance. In this paper, we develop a scalable parallel algorithm based on domain decomposition methods to investigate an unsteady model with patient-specific pulsatile waveforms as the inlet boundary condition. The unsteady model offers tremendously more information about the dynamic behavior of the flow field, but computationally speaking, the simulation is a lot more expensive since a problem which is similar to the steady-state problem has to be solved many times, and therefore, the traditional sequential approach is not suitable anymore. We show computationally that simulations using the proposed parallel approach with up to 10 000 processor cores can be obtained with much reduced compute time. This makes the technology potentially usable for the routine study of the dynamic behavior of blood flows in the pulmonary artery, in particular, the changes of the blood flows and the wall shear stress in the spatial and temporal dimensions.
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Affiliation(s)
- Fande Kong
- Modeling and Simulation, Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-3840, USA
| | - Vitaly Kheyfets
- School of Medicine, University of Colorado Denver, Aurora, CO 80045-7109, USA
| | - Ender Finol
- Department of Mechanical Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Xiao-Chuan Cai
- Department of Computer Science, University of Colorado Boulder, Boulder, CO 80309-0430, USA
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30
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Ni MW, Prather RO, Rodriguez G, Quinn R, Divo E, Fogel M, Kassab AJ, DeCampli WM. Computational Investigation of a Self-Powered Fontan Circulation. Cardiovasc Eng Technol 2018; 9:202-216. [PMID: 29464511 DOI: 10.1007/s13239-018-0342-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 02/12/2018] [Indexed: 11/25/2022]
Abstract
Children born with anatomic or functional "single ventricle" must progress through two or more major operations to sustain life. This management sequence culminates in the total cavopulmonary connection, or "Fontan" operation. A consequence of the "Fontan circulation", however, is elevated central venous pressure and inadequate ventricular preload, which contribute to continued morbidity. We propose a solution to these problems by increasing pulmonary blood flow using an "injection jet" (IJS) in which the source of blood flow and energy is the ventricle itself. The IJS has the unique property of lowering venous pressure while enhancing pulmonary blood flow and ventricular preload. We report preliminary results of an analysis of this circulation using a tightly-coupled, multi-scale computational fluid dynamics model. Our calculations show that, constraining the excess volume load to the ventricle at 50% (pulmonary to systemic flow ratio of 1.5), an optimally configured IJS can lower venous pressure by 3 mmHg while increasing systemic oxygen delivery. Even this small decrease in venous pressure may have substantial clinical impact on the Fontan patient. These findings support the potential for a straightforward surgical modification to decrease venous pressure, and perhaps improve clinical outcome in selected patients.
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Affiliation(s)
- Marcus W Ni
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, 32816, USA.
| | - Ray O Prather
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, 32816, USA
| | - Giovanna Rodriguez
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, 32816, USA
| | - Rachel Quinn
- College of Medicine, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, USA
| | - Eduardo Divo
- Department of Mechanical Engineering, Embry-Riddle Aeronautical University, 600 S Clyde Morris Blvd, Daytona Beach, FL, USA
| | - Mark Fogel
- The Perelman School of Medicine at The University of Pennsylvania, Philadelphia, PA, USA.,Division of Cardiology/Department of Pediatrics and the Department of Radiology, The Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA, USA
| | - Alain J Kassab
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, 32816, USA
| | - William M DeCampli
- College of Medicine, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL, USA.,Arnold Palmer Hospital for Children, 92 W Miller St, Orlando, FL, USA
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31
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Si B, Qiao B, Yang G, Zhu M, Zhao F, Wang T, Li N, Ji X, Ding G. Numerical Investigation of the Effect of Additional Pulmonary Blood Flow on Patient-Specific Bilateral Bidirectional Glenn Hemodynamics. Cardiovasc Eng Technol 2018; 9:193-201. [PMID: 29359262 DOI: 10.1007/s13239-018-0341-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 01/12/2018] [Indexed: 10/18/2022]
Abstract
The effect of additional pulmonary blood flow (APBF) on the hemodynamics of bilateral bidirectional Glenn (BBDG) connection was marginally discussed in previous studies. This study assessed this effect using patient-specific numerical simulation. A 15-year-old female patient who underwent BBDG was enrolled in this study. Patient-specific anatomy, flow waveforms, and pressure tracings were obtained using computed tomography, Doppler ultrasound technology, and catheterization, respectively. Computational fluid dynamic simulations were performed to assess flow field and derived hemodynamic metrics of the BBDG connection with various APBF. APBF showed noticeable effects on the hemodynamics of the BBDG connection. It suppressed flow mixing in the connection, which resulted in a more antegrade flow structure. Also, as the APBF rate increases, both power loss and reflux in superior venae cavae (SVCs) monotonically increases while the flow ratio of the right to the left pulmonary artery (RPA/LPA) monotonically decreases. However, a non-monotonic relationship was observed between the APBF rate and indexed power loss. A high APBF rate may result in a good flow ratio of RPA/LPA but with the side effect of bad power loss and remarkable reflux in SVCs, and vice versa. A moderate APBF rate could be favourable because it leads to an optimal indexed power loss and achieves the acceptable flow ratio of RPA/LPA without causing severe power loss and reflux in SVCs. These findings suggest that patient-specific numerical simulation should be used to assist clinicians in determining an appropriate APBF rate based on desired outcomes on a patient-specific basis.
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Affiliation(s)
- Biao Si
- Department of Mechanics and Engineering Science, Fudan University, No. 220, Handan Road, Shanghai, China.,Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China.,Institute of Computational Science and Cardiovascular Disease, Nanjing Medical University, Nanjing, China
| | - Bin Qiao
- Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China.,Institute of Computational Science and Cardiovascular Disease, Nanjing Medical University, Nanjing, China
| | - Guang Yang
- Wuxi Mingci Cardiovascular Hospital, Wuxi, China
| | - Meng Zhu
- Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China
| | - Fengyu Zhao
- Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China
| | - Tongjian Wang
- Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China
| | - Na Li
- Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China
| | - Xiaopeng Ji
- Shandong Medical Imaging Research Institute, Shandong University, Jinan, China
| | - Guanghong Ding
- Department of Mechanics and Engineering Science, Fudan University, No. 220, Handan Road, Shanghai, China.
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32
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Grigioni M, Daniele C, Del Gaudio C, Morbiducci U, Balducci A, D'Avenio G, Amodeo A, Barbaro V, Di Donato R. Numerical Simulation of a Realistic Total Cavo-pulmonary Connection: Effect of Unbalanced Pulmonary Resistances on Hydrodynamic Performance. Int J Artif Organs 2018; 26:1005-14. [PMID: 14708830 DOI: 10.1177/039139880302601107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Total cavo pulmonary connection (TCPC) is one of the surgical techniques adopted to compensate the failure of the right heart in pediatric patients. The main goal of this procedure is the realization of a configuration for the caval veins and for the pulmonary arteries that can guarantee as low as possible pressure losses and appropriate lung perfusion. Starting from this point of view, a realistic TCPC with extracardiac conduit (TECPC) is investigated by means of Computational Fluid Dynamics (CFD) to evaluate the pressure loss under different pressure conditions, simulating different vessel resistances, on the pulmonary arteries. A total flow of 3 L/min, with a distribution between the inferior vena cava (IVC) and the superior vena cava (SVC) equal to 6/4, was investigated; three different boundary conditions for the pressure were imposed, resulting in three simulations in steady-state conditions, to the right pulmonary artery (RPA) and to the left pulmonary artery (LPA), simulating a balanced (deltaP(LPA-RPA) = 0 mmHg) and two unbalanced pulmonary resistances to blood flow (a pressure difference deltaP(LPA-RPA) = +/- 2 mmHg, respectively). The geometry for the TECPC was realized according to MRI derived physiological values for the vessels and for the configuration adopted for the anastomosis (the extra-cardiac conduit was inclined 22 degrees towards the left pulmonary artery with respect to the IVC axis). The computed power losses agree with previous in vitro Particle Image Velocimetry investigations. The results show that a higher resistance on the LPA causes the greater pressure loss for the TECPC under study, while the minimum pressure loss can be achieved balancing the pulmonary resistances, subsequently obtaining a balanced flow repartition towards the lungs.
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Affiliation(s)
- M Grigioni
- Laboratory of Biomedical Engineering, Istituto Superiore di Sanità, Rome, Italy.
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33
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Malota Z, Nawrat Z, Kostka P, Mizerski J, Nowinski K, Waniewski J. Physical and Computer Modelling of Blood Flow in a Systemic-to-pulmonary Shunt. Int J Artif Organs 2018; 27:990-9. [PMID: 15636057 DOI: 10.1177/039139880402701112] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this work was the application of computer and physical in vitro simulation methods for estimating surgery procedure hemodynamics. The modified Blalock-Taussig (mB-T) palliative surgical procedure is performed to increase the pulmonary blood flow in children with congenital heart defects. Such a systemic-to-pulmonary shunt yields substantial modification in the blood flow within the large blood vessels. The objective of the present study was to investigate basic characteristics of the flow, flow pattern and pressure-flow efficiency, before and after opening of the mB-T graft. Methods The model was based on the vessel geometry obtained from the Visible Human Project and included the arch of aorta, the three arteries branching from the arch, the pulmonary trunck, and the left and right pulmonary arteries. The graft was added between the left subclavian artery and the left pulmonary artery. The glass model of the vessels was produced and investigated in a physical model of the cardiovascular system with an artificial ventricular device as the blood pump. Flow rate and hydrostatic pressure were measured at the inlet to and outlets from the glass model and in a few points within the system. Laser flow visualization was also performed. Computer simulations were done using the boundary conditions from the physical model. Results The opening of the mB-T graft changed flow distribution in all branches (including inflow). A complex flow pattern with large eddies and channelling of the flow in the vicinity of the graft and within it was observed in flow visualization and in computer simulations. Because of that complexity the local measurements of hydrostatic pressure at the vessel wall could not predict the average flow rate. The reversed flow in the graft was observed during the systole. Conclusions The complex flow pattern developed in the physical model of the mB-T graft. The channelling of the flow and the formation of large eddies may yield high shear stress and modify blood properties. The rigid wall model can describe only some flow characteristics observed in vivo. Computer simulation is a very fast and accurate method which permits earlier qualification of cardiac surgeons on how to change cardiac vascular blood flow after operations.
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Affiliation(s)
- Z Malota
- Foundation of Cardiac Surgery Development, Zabrze, Poland.
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34
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MaƗota Z, Nawrat Z, Kostka P. Computer and Physical Modeling of Blood Circulation Pump Support for a New Field of Application in Palliative Surgery. Int J Artif Organs 2018; 30:1068-74. [DOI: 10.1177/039139880703001206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives One of the most popular palliative procedures performed to increase pulmonary blood flow in children with congenital heart defects is a shunt operation (Blalock-Taussig graft or Glenn procedure), which creates the new blood channel to the pulmonary artery. The main problem with this kind of surgery is poor shunt effectiveness and the lack of possibility to regulate the flow. The aim of this work is to use advanced computer simulation methods to study the effectiveness of a new idea to introduce a small axial blood pump into a Blalock-Taussig (B-T) or Glenn shunt in order to control the blood flow and prevent any increase in the graft stenosis. Methods Physical and computer 3-D simulation based on a finite element mesh (FEM) model was applied. Studies for optimization of the shunt and hybrid shunt with pump were performed for different stages of the disease. Results and Conclusion The graft with the axial pump creates good conditions for the vascular system and pulmonary artery blood flow as well as regulating blood pressure under variable conditions caused by palliative procedures. Its use permits the afterload of the left heart ventricle to be decreased. A palliative procedure is only a temporary solution. When a child grows, while the graft size is fixed, the blood flow through this graft may be not sufficient under changing hemodynamic conditions. The use of an axial pump for regulating the blood flow volume, during palliative procedures, allows to obtain the optimal flow conditions in pulmonary artery and safely wait on the final cardiac surgery correction later. However, the use of a pump mounted inside the graft increased hemodynamic resistance, which caused the flow to decrease up to 70% in the graft when the axial pump was not working.
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Affiliation(s)
- Z. MaƗota
- Foundation of Cardiac Surgery Development, Zabrze - Poland
| | - Z. Nawrat
- Foundation of Cardiac Surgery Development, Zabrze - Poland
- Silesian Medical Academy, Zabrze - Poland
| | - P. Kostka
- Foundation of Cardiac Surgery Development, Zabrze - Poland
- Silesian University of Technology, Gliwice - Poland
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35
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Single ventricle i-simulation. J Thorac Cardiovasc Surg 2017; 155:724-725. [PMID: 29224836 DOI: 10.1016/j.jtcvs.2017.10.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 10/26/2017] [Indexed: 11/22/2022]
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36
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Honda T, Itatani K, Takanashi M, Kitagawa A, Ando H, Kimura S, Oka N, Miyaji K, Ishii M. Exploring energy loss by vector flow mapping in children with ventricular septal defect: Pathophysiologic significance. Int J Cardiol 2017. [DOI: 10.1016/j.ijcard.2017.06.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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37
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Computational Fluid Dynamics and Additive Manufacturing to Diagnose and Treat Cardiovascular Disease. Trends Biotechnol 2017; 35:1049-1061. [PMID: 28942268 DOI: 10.1016/j.tibtech.2017.08.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 08/20/2017] [Accepted: 08/23/2017] [Indexed: 11/21/2022]
Abstract
Noninvasive engineering models are now being used for diagnosing and planning the treatment of cardiovascular disease. Techniques in computational modeling and additive manufacturing have matured concurrently, and results from simulations can inform and enable the design and optimization of therapeutic devices and treatment strategies. The emerging synergy between large-scale simulations and 3D printing is having a two-fold benefit: first, 3D printing can be used to validate the complex simulations, and second, the flow models can be used to improve treatment planning for cardiovascular disease. In this review, we summarize and discuss recent methods and findings for leveraging advances in both additive manufacturing and patient-specific computational modeling, with an emphasis on new directions in these fields and remaining open questions.
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Puelz C, Acosta S, Rivière B, Penny DJ, Brady KM, Rusin CG. A computational study of the Fontan circulation with fenestration or hepatic vein exclusion. Comput Biol Med 2017; 89:405-418. [PMID: 28881280 DOI: 10.1016/j.compbiomed.2017.08.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 08/02/2017] [Accepted: 08/22/2017] [Indexed: 12/14/2022]
Abstract
Fontan patients may undergo additional surgical modifications to mitigate complications like protein-losing enteropathy, liver cirrhosis, and other issues in their splanchnic circulation. Recent case reports show promise for several types of modifications, but the subtle effects of these surgeries on the circulation are not well understood. In this paper, we employ mathematical modeling of blood flow to systematically quantify the impact of these surgical changes on extracardiac Fontan hemodynamics. We investigate two modifications: (1) the fenestrated Fontan and (2) the Fontan with hepatic vein exclusion. Closed-loop hemodynamic models are used, which consist of one-dimensional networks for the major vessels and zero-dimensional models for the heart and organ beds. Numerical results suggest the hepatic vein exclusion has the greatest overall impact on the hemodynamics, followed by the largest sized fenestration. In particular, the hepatic vein exclusion drastically lowers portal venous pressure while the fenestration decreases pulmonary artery pressure. Both modifications increase flow to the intestines, a finding consistent with their utility in clinical practice for combating complications in the splanchnic circulation.
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Affiliation(s)
- Charles Puelz
- Department of Computational and Applied Mathematics, Rice University, Houston, TX, USA.
| | - Sebastián Acosta
- Department of Pediatrics-Cardiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
| | - Béatrice Rivière
- Department of Computational and Applied Mathematics, Rice University, Houston, TX, USA
| | - Daniel J Penny
- Department of Pediatrics-Cardiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
| | - Ken M Brady
- Department of Anesthesiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
| | - Craig G Rusin
- Department of Pediatrics-Cardiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
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Jia Y, Qiao Y, Ricardo Argueta-Morales I, Maung A, Norfleet J, Bai Y, Divo E, Kassab AJ, DeCampli WM. Experimental Study of Anisotropic Stress/Strain Relationships of Aortic and Pulmonary Artery Homografts and Synthetic Vascular Grafts. J Biomech Eng 2017; 139:2646917. [DOI: 10.1115/1.4037400] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Indexed: 11/08/2022]
Abstract
Homografts and synthetic grafts are used in surgery for congenital heart disease (CHD). Determining these materials' mechanical properties will aid in understanding tissue behavior when subjected to abnormal CHD hemodynamics. Homograft tissue samples from anterior/posterior aspects, of ascending/descending aorta (AA, DA), innominate artery (IA), left subclavian artery (LScA), left common carotid artery (LCCA), main/left/right pulmonary artery (MPA, LPA, RPA), and synthetic vascular grafts, were obtained in three orientations: circumferential, diagonal (45 deg relative to circumferential direction), and longitudinal. Samples were subjected to uniaxial tensile testing (UTT). True strain-Cauchy stress curves were individually fitted for each orientation to calibrate Fung model. Then, they were used to calibrate anisotropic Holzapfel–Gasser model (R2 > 0.95). Most samples demonstrated a nonlinear hyperelastic strain–stress response to UTT. Stiffness (measured by tangent modulus at different strains) in all orientations were compared and shown as contour plots. For each vessel segment at all strain levels, stiffness was not significantly different among aspects and orientations. For synthetic grafts, stiffness was significantly different among orientations (p < 0.042). Aorta is significantly stiffer than pulmonary artery at 10% strain, comparing all orientations, aspects, and regions (p = 0.0001). Synthetic grafts are significantly stiffer than aortic and pulmonary homografts at all strain levels (p < 0.046). Aortic, pulmonary artery, and synthetic grafts exhibit hyperelastic biomechanical behavior with anisotropic effect. Differences in mechanical properties among vascular grafts may affect native tissue behavior and ventricular/arterial mechanical coupling, and increase the risk of deformation due to abnormal CHD hemodynamics.
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Affiliation(s)
- Yueqian Jia
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816
| | - Yangyang Qiao
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816
| | - I. Ricardo Argueta-Morales
- Cardiothoracic Surgery, The Heart Center at Arnold Palmer Hospital for Children, 92 West Miller Street, Orlando, FL 32806
| | - Aung Maung
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816
| | - Jack Norfleet
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816
| | - Yuanli Bai
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 e-mail:
| | - Eduardo Divo
- Department of Mechanical Engineering, College of Engineering, Embry-Riddle Aeronautical University, 600 South Clyde Morris Boulevard, Daytona Beach, FL 32114
| | - Alain J. Kassab
- Department of Mechanical and Aerospace Engineering, College of Engineering and Computer Science, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816
| | - William M. DeCampli
- Cardiothoracic Surgery, The Heart Center at Arnold Palmer Hospital for Children, 92 West Miller Street, Orlando, FL 32806
- Medical Education, College of Medicine, University of Central Florida, 6850 Lake Nona Boulevard, Orlando, FL 32827 e-mail:
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40
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Oguz GN, Piskin S, Ermek E, Donmazov S, Altekin N, Arnaz A, Pekkan K. Increased Energy Loss Due to Twist and Offset Buckling of the Total Cavopulmonary Connection. J Med Device 2017. [DOI: 10.1115/1.4035981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The hemodynamic energy loss through the surgically implanted conduits determines the postoperative cardiac output and exercise capacity following the palliative repair of single-ventricle congenital heart defects. In this study, the hemodynamics of severely deformed surgical pathways due to torsional deformation and anastomosis offset are investigated. We designed a mock-up total cavopulmonary connection (TCPC) circuit to replicate the mechanically failed inferior vena cava (IVC) anastomosis morphologies under physiological venous pressure (9, 12, 15 mmHg), in vitro, employing the commonly used conduit materials: Polytetrafluoroethylene (PTFE), Dacron, and porcine pericardium. The sensitivity of hemodynamic performance to torsional deformation for three different twist angles (0 deg, 30 deg, and 60 deg) and three different caval offsets (0 diameter (D), 0.5D, and 1D) are digitized in three dimensions and employed in computational fluid dynamic (CFD) simulations to determine the corresponding hydrodynamic efficiency levels. A total of 81 deformed conduit configurations are analyzed; the pressure drop values increased from 80 to 1070% with respect to the ideal uniform diameter IVC conduit flow. The investigated surgical materials resulted in significant variations in terms of flow separation and energy loss. For example, the porcine pericardium resulted in a pressure drop that was eight times greater than the Dacron conduit. Likewise, PTFE conduit resulted in a pressure drop that was three times greater than the Dacron conduit under the same venous pressure loading. If anastomosis twist and/or caval offset cannot be avoided intraoperatively due to the anatomy of the patient, alternative conduit materials with high structural stiffness and less influence on hemodynamics can be considered.
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Affiliation(s)
- Gokce Nur Oguz
- Department of Mechanical Engineering, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Senol Piskin
- Department of Mechanical Engineering, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Erhan Ermek
- Department of Mechanical Engineering, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Samir Donmazov
- Department of Mechanical Engineering, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Naz Altekin
- Department of Mechanical Engineering, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Ahmet Arnaz
- Department of Cardiovascular Surgery, Acıbadem Bakırköy Hospital, Istanbul 34450, Turkey
| | - Kerem Pekkan
- Department of Mechanical Engineering, Koç University, Rumeli Feneri Campus, Sarıyer, Istanbul 34450, Turkey e-mail:
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41
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Negin Mortazavi S, Geddes D, Hassanipour F. Lactation in the Human Breast From a Fluid Dynamics Point of View. J Biomech Eng 2016; 139:2571656. [DOI: 10.1115/1.4034995] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Indexed: 11/08/2022]
Abstract
This study is a collaborative effort among lactation specialists and fluid dynamic engineers. The paper presents clinical results for suckling pressure pattern in lactating human breast as well as a 3D computational fluid dynamics (CFD) modeling of milk flow using these clinical inputs. The investigation starts with a careful, statistically representative measurement of suckling vacuum pressure, milk flow rate, and milk intake in a group of infants. The results from clinical data show that suckling action does not occur with constant suckling rate but changes in a rhythmic manner for infants. These pressure profiles are then used as the boundary condition for the CFD study using commercial ansys fluent software. For the geometric model of the ductal system of the human breast, this work takes advantage of a recent advance in the development of a validated phantom that has been produced as a ground truth for the imaging applications for the breast. The geometric model is introduced into CFD simulations with the aforementioned boundary conditions. The results for milk intake from the CFD simulation and clinical data were compared and cross validated. Also, the variation of milk intake versus suckling pressure are presented and analyzed. Both the clinical and CFD simulation show that the maximum milk flow rate is not related to the largest vacuum pressure or longest feeding duration indicating other factors influence the milk intake by infants.
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Affiliation(s)
- S. Negin Mortazavi
- Department of Mechanical Engineering, University of Texas at Dallas, Richardson, TX 75080 e-mail:
| | - Donna Geddes
- School of Chemistry and Biochemistry, University of Western Australia, Crawley, Western Australia 6009, Australia e-mail:
| | - Fatemeh Hassanipour
- Department of Mechanical Engineering, University of Texas at Dallas, Richardson, TX 75080 e-mail:
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42
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Biglino G, Capelli C, Bruse J, Bosi GM, Taylor AM, Schievano S. Computational modelling for congenital heart disease: how far are we from clinical translation? Heart 2016; 103:98-103. [PMID: 27798056 PMCID: PMC5284484 DOI: 10.1136/heartjnl-2016-310423] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/26/2016] [Accepted: 09/29/2016] [Indexed: 12/17/2022] Open
Abstract
Computational models of congenital heart disease (CHD) have become increasingly sophisticated over the last 20 years. They can provide an insight into complex flow phenomena, allow for testing devices into patient-specific anatomies (pre-CHD or post-CHD repair) and generate predictive data. This has been applied to different CHD scenarios, including patients with single ventricle, tetralogy of Fallot, aortic coarctation and transposition of the great arteries. Patient-specific simulations have been shown to be informative for preprocedural planning in complex cases, allowing for virtual stent deployment. Novel techniques such as statistical shape modelling can further aid in the morphological assessment of CHD, risk stratification of patients and possible identification of new ‘shape biomarkers’. Cardiovascular statistical shape models can provide valuable insights into phenomena such as ventricular growth in tetralogy of Fallot, or morphological aortic arch differences in repaired coarctation. In a constant move towards more realistic simulations, models can also account for multiscale phenomena (eg, thrombus formation) and importantly include measures of uncertainty (ie, CIs around simulation results). While their potential to aid understanding of CHD, surgical/procedural decision-making and personalisation of treatments is undeniable, important elements are still lacking prior to clinical translation of computational models in the field of CHD, that is, large validation studies, cost-effectiveness evaluation and establishing possible improvements in patient outcomes.
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Affiliation(s)
- Giovanni Biglino
- Bristol Heart Institute, School of Clinical Sciences, University of Bristol, Bristol, UK.,Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK
| | - Claudio Capelli
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.,Institute of Cardiovascular Science, University College London, London, UK
| | - Jan Bruse
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.,Institute of Cardiovascular Science, University College London, London, UK
| | - Giorgia M Bosi
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.,Institute of Cardiovascular Science, University College London, London, UK
| | - Andrew M Taylor
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.,Institute of Cardiovascular Science, University College London, London, UK
| | - Silvia Schievano
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK.,Institute of Cardiovascular Science, University College London, London, UK
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43
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Kumar R, Samuel S, Sai KS, Vakamudi M, Saldanha R, Balakrishnan KR. Extracardiac Fontan/Kawashima Procedure without Cardiopulmonary Bypass. Asian Cardiovasc Thorac Ann 2016. [DOI: 10.1177/021849230000800318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Two patients with univentricular physiology underwent successful surgical palliation without the use of cardiopulmonary bypass. A 19-year-old girl had an extracardiac Fontan operation and a 4-year-old boy had a Kawashima-type repair with a bilateral bidirectional Glenn procedure.
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Affiliation(s)
- Rajiv Kumar
- Department of Cardiothoracic Surgery Sri Ramachandra Hospital Chennai, India
| | - Susan Samuel
- Department of Cardiothoracic Surgery Sri Ramachandra Hospital Chennai, India
| | - K Srinivas Sai
- Department of Cardiothoracic Surgery Sri Ramachandra Hospital Chennai, India
| | - Mahesh Vakamudi
- Department of Cardiothoracic Surgery Sri Ramachandra Hospital Chennai, India
| | - Richard Saldanha
- Department of Cardiothoracic Surgery Sri Ramachandra Hospital Chennai, India
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44
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Plummer ST, Hornik CP, Baker H, Fleming GA, Foerster S, Ferguson ME, Glatz AC, Hirsch R, Jacobs JP, Lee KJ, Lewis AB, Li JS, Martin M, Porras D, Radtke WAK, Rhodes JF, Vincent JA, Zampi JD, Hill KD. Maladaptive aortic properties after the Norwood procedure: An angiographic analysis of the Pediatric Heart Network Single Ventricle Reconstruction Trial. J Thorac Cardiovasc Surg 2016; 152:471-479.e3. [PMID: 27167022 DOI: 10.1016/j.jtcvs.2016.03.091] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 03/07/2016] [Accepted: 03/13/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Aortic arch reconstruction in children with single ventricle lesions may predispose to circulatory inefficiency and maladaptive physiology leading to increased myocardial workload. We sought to describe neoaortic anatomy and physiology, risk factors for abnormalities, and impact on right ventricular function in patients with single right ventricle lesions after arch reconstruction. METHODS Prestage II aortic angiograms from the Pediatric Heart Network Single Ventricle Reconstruction trial were analyzed to define arch geometry (Romanesque [normal], crenel [elongated], or gothic [angular]), indexed neoaortic dimensions, and distensibility. Comparisons were made with 50 single-ventricle controls without prior arch reconstruction. Factors associated with ascending neoaortic dilation, reduced distensibility, and decreased ventricular function on the 14-month echocardiogram were evaluated using univariate and multivariable logistic regression. RESULTS Interpretable angiograms were available for 326 of 389 subjects (84%). Compared with controls, study subjects more often demonstrated abnormal arch geometry (67% vs 22%, P < .01) and had increased ascending neoaortic dilation (Z score 3.8 ± 2.2 vs 2.6 ± 2.0, P < .01) and reduced distensibility index (2.2 ± 1.9 vs 8.0 ± 3.8, P < .01). Adjusted odds of neoaortic dilation were increased in subjects with gothic arch geometry (odds ratio [OR], 3.2 vs crenel geometry, P < .01) and a right ventricle-pulmonary artery shunt (OR, 3.4 vs Blalock-Taussig shunt, P < .01) but were decreased in subjects with aortic atresia (OR, 0.7 vs stenosis, P < .01) and those with recoarctation (OR, 0.3 vs no recoarctation, P = .04). No demographic, anatomic, or surgical factors predicted reduced distensibility. Neither dilation nor distensibility predicted reduced right ventricular function. CONCLUSIONS After Norwood surgery, the reconstructed neoaorta demonstrates abnormal anatomy and physiology. Further study is needed to evaluate the longer-term impact of these features.
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Affiliation(s)
| | | | | | | | | | - M Eric Ferguson
- Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga
| | | | - Russel Hirsch
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Jeffrey P Jacobs
- Johns Hopkins Children's Heart Surgery, All Children's Hospital and Florida Hospital for Children, St Petersburg, Tampa, and Orlando, Fla
| | - Kyong-Jin Lee
- Hospital for Sick Children, Toronto, Ontario, Canada
| | - Alan B Lewis
- Children's Hospital Los Angeles, Los Angeles, Calif
| | | | - Mary Martin
- University of Utah School of Medicine, Salt Lake City, Utah
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45
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Bonnichsen C, Ammash N. Choosing Between MRI and CT Imaging in the Adult with Congenital Heart Disease. Curr Cardiol Rep 2016; 18:45. [DOI: 10.1007/s11886-016-0717-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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46
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Hsia TY, Figliola R. Multiscale modelling of single-ventricle hearts for clinical decision support: a Leducq Transatlantic Network of Excellence. Eur J Cardiothorac Surg 2015; 49:365-8. [PMID: 26489838 DOI: 10.1093/ejcts/ezv368] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Tain-Yen Hsia
- Department of Cardiothoracic Surgery, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Richard Figliola
- Department of Mechanical and Bioengineering, Clemson University, Clemson, NC, USA
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47
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Abstract
PURPOSE OF REVIEW Recent methodological advances in computational simulations are enabling increasingly realistic simulations of hemodynamics and physiology, driving increased clinical utility. We review recent developments in the use of computational simulations in pediatric and congenital heart disease, describe the clinical impact in modeling in single-ventricle patients, and provide an overview of emerging areas. RECENT FINDINGS Multiscale modeling combining patient-specific hemodynamics with reduced order (i.e., mathematically and computationally simplified) circulatory models has become the de-facto standard for modeling local hemodynamics and 'global' circulatory physiology. We review recent advances that have enabled faster solutions, discuss new methods (e.g., fluid structure interaction and uncertainty quantification), which lend realism both computationally and clinically to results, highlight novel computationally derived surgical methods for single-ventricle patients, and discuss areas in which modeling has begun to exert its influence including Kawasaki disease, fetal circulation, tetralogy of Fallot (and pulmonary tree), and circulatory support. SUMMARY Computational modeling is emerging as a crucial tool for clinical decision-making and evaluation of novel surgical methods and interventions in pediatric cardiology and beyond. Continued development of modeling methods, with an eye towards clinical needs, will enable clinical adoption in a wide range of pediatric and congenital heart diseases.
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48
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Cibis M, Jarvis K, Markl M, Rose M, Rigsby C, Barker AJ, Wentzel JJ. The effect of resolution on viscous dissipation measured with 4D flow MRI in patients with Fontan circulation: Evaluation using computational fluid dynamics. J Biomech 2015; 48:2984-9. [PMID: 26298492 DOI: 10.1016/j.jbiomech.2015.07.039] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 07/03/2015] [Accepted: 07/30/2015] [Indexed: 10/23/2022]
Abstract
Viscous dissipation inside Fontan circulation, a parameter associated with the exercise intolerance of Fontan patients, can be derived from computational fluid dynamics (CFD) or 4D flow MRI velocities. However, the impact of spatial resolution and measurement noise on the estimation of viscous dissipation is unclear. Our aim was to evaluate the influence of these parameters on viscous dissipation calculation. Six Fontan patients underwent whole heart 4D flow MRI. Subject-specific CFD simulations were performed. The CFD velocities were down-sampled to isotropic spatial resolutions of 0.5mm, 1mm, 2mm and to MRI resolution. Viscous dissipation was compared between (1) high resolution CFD velocities, (2) CFD velocities down-sampled to MRI resolution, (3) down-sampled CFD velocities with MRI mimicked noise levels, and (4) in-vivo 4D flow MRI velocities. Relative viscous dissipation between subjects was also calculated. 4D flow MRI velocities (15.6 ± 3.8 cm/s) were higher, although not significantly different than CFD velocities (13.8 ± 4.7 cm/s, p=0.16), down-sampled CFD velocities (12.3 ± 4.4 cm/s, p=0.06) and the down-sampled CFD velocities with noise (13.2 ± 4.2 cm/s, p=0.06). CFD-based viscous dissipation (0.81 ± 0.55 mW) was significantly higher than those based on down-sampled CFD (0.25 ± 0.19 mW, p=0.03), down-sampled CFD with noise (0.49 ± 0.26 mW, p=0.03) and 4D flow MRI (0.56 ± 0.28 mW, p=0.06). Nevertheless, relative viscous dissipation between different subjects was maintained irrespective of resolution and noise, suggesting that comparison of viscous dissipation between patients is still possible.
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Affiliation(s)
- Merih Cibis
- Biomedical Engineering, Erasmus Medical Center, Rotterdam, Netherlands.
| | - Kelly Jarvis
- Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States; Biomedical Engineering, Northwestern University, Chicago, IL, United States
| | - Michael Markl
- Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States; Biomedical Engineering, Northwestern University, Chicago, IL, United States
| | - Michael Rose
- Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States
| | - Cynthia Rigsby
- Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States; Medical Imaging, Ann & Robert H Lurie Children's Hospital of Chicago, Chicago, IL, United States
| | - Alex J Barker
- Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States
| | - Jolanda J Wentzel
- Biomedical Engineering, Erasmus Medical Center, Rotterdam, Netherlands
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49
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Bhat AN, Rahmath MR, John J, Bhaskar P, Dilawar M. Modified Blalock Taussig shunt for management of severe desaturation following bidirectional superior cavopulmonary anastomosis in a 3-month-old child. Indian J Thorac Cardiovasc Surg 2015. [DOI: 10.1007/s12055-014-0355-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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50
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Experimental Study of Anisotropic Stress/Strain Relationships of the Piglet Great Vessels and Relevance to Pediatric Congenital Heart Disease. Ann Thorac Surg 2015; 99:1399-407. [DOI: 10.1016/j.athoracsur.2014.11.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 11/03/2014] [Accepted: 11/17/2014] [Indexed: 11/23/2022]
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