1
|
Ahmad Azahari AFA, Wan Ab Naim WN, Md Sari NA, Lim E, Mohamed Mokhtarudin MJ. Advancement in computational simulation and validation of congenital heart disease: a review. Comput Methods Biomech Biomed Engin 2024:1-14. [PMID: 39001803 DOI: 10.1080/10255842.2024.2377338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 07/02/2024] [Indexed: 07/15/2024]
Abstract
The improvement in congenital heart disease (CHD) treatment and management has increased the life expectancy in infants. However, the long-term efficacy is difficult to assess and thus, computational modelling has been applied for evaluating this. Here, we provide an overview of the applications of computational modelling in CHD based on three categories; CHD involving large blood vessels only, heart chambers only, and CHD that occurs at multiple heart structures. We highlight the advancement of computational simulation of CHD that uses multiscale and multiphysics modelling to ensure a complete representation of the heart and circulation. We provide a brief future direction of computational modelling of CHD such as to include growth and remodelling, detailed conduction system, and occurrence of myocardial infarction. We also proposed validation technique using advanced three-dimensional (3D) printing and particle image velocimetry (PIV) technologies to improve the model accuracy.
Collapse
Affiliation(s)
| | - Wan Naimah Wan Ab Naim
- Faculty of Manufacturing and Mechatronic Engineering Technology, Universiti Malaysia Pahang, Pekan, Pahang, Malaysia
| | - Nor Ashikin Md Sari
- Division of Cardiology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Einly Lim
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Jamil Mohamed Mokhtarudin
- Faculty of Manufacturing and Mechatronic Engineering Technology, Universiti Malaysia Pahang, Pekan, Pahang, Malaysia
- Centre for Research in Advanced Fluid and Processes (Fluid Centre), Universiti Malaysia Pahang, Lebuhraya Tun Razak, Kuantan, Pahang, Malaysia
| |
Collapse
|
2
|
Govindarajan V, Marshall L, Sahni A, Cetatoiu MA, Eickhoff EE, Davee J, St Clair N, Schulz NE, Hoganson DM, Hammer PE, Ghelani SJ, Prakash A, Del Nido PJ, Rathod RH. Impact of Age-Related Change in Caval Flow Ratio on Hepatic Flow Distribution in the Fontan Circulation. Circ Cardiovasc Imaging 2024; 17:e016104. [PMID: 38567518 PMCID: PMC11073583 DOI: 10.1161/circimaging.123.016104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 03/15/2024] [Indexed: 04/04/2024]
Abstract
BACKGROUND The Fontan operation is a palliative technique for patients born with single ventricle heart disease. The superior vena cava (SVC), inferior vena cava (IVC), and hepatic veins are connected to the pulmonary arteries in a total cavopulmonary connection by an extracardiac conduit or a lateral tunnel connection. A balanced hepatic flow distribution (HFD) to both lungs is essential to prevent pulmonary arteriovenous malformations and cyanosis. HFD is highly dependent on the local hemodynamics. The effect of age-related changes in caval inflows on HFD was evaluated using cardiac magnetic resonance data and patient-specific computational fluid dynamics modeling. METHODS SVC and IVC flow from 414 patients with Fontan were collected to establish a relationship between SVC:IVC flow ratio and age. Computational fluid dynamics modeling was performed in 60 (30 extracardiac and 30 lateral tunnel) patient models to quantify the HFD that corresponded to patient ages of 3, 8, and 15 years, respectively. RESULTS SVC:IVC flow ratio inverted at ≈8 years of age, indicating a clear shift to lower body flow predominance. Our data showed that variation of HFD in response to age-related changes in caval inflows (SVC:IVC, 2, 1, and 0.5 corresponded to ages, 3, 8, and 15+, respectively) was not significant for extracardiac but statistically significant for lateral tunnel cohorts. For all 3 caval inflow ratios, a positive correlation existed between the IVC flow distribution to both the lungs and the HFD. However, as the SVC:IVC ratio changed from 2 to 0.5 (age, 3-15+) years, the correlation's strength decreased from 0.87 to 0.64, due to potential flow perturbation as IVC flow momentum increased. CONCLUSIONS Our analysis provided quantitative insights into the impact of the changing caval inflows on Fontan's long-term HFD, highlighting the importance of SVC:IVC variations over time on Fontan's long-term hemodynamics. These findings broaden our understanding of Fontan hemodynamics and patient outcomes.
Collapse
Affiliation(s)
- Vijay Govindarajan
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Surgery (V.G., D.M.H., P.E.H.), Harvard Medical School, Boston, MA
- Department of Internal Medicine, University of Texas Health Science Center at Houston (V.G.)
| | - Lauren Marshall
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Akshita Sahni
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Maria A Cetatoiu
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Emily E Eickhoff
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Jocelyn Davee
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Nicole St Clair
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - Noah E Schulz
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
| | - David M Hoganson
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Surgery (V.G., D.M.H., P.E.H.), Harvard Medical School, Boston, MA
| | - Peter E Hammer
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Surgery (V.G., D.M.H., P.E.H.), Harvard Medical School, Boston, MA
| | - Sunil J Ghelani
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Cardiology (S.J.G., A.P., P.J.d.N., R.H.R.), Boston Children's Hospital, MA
| | - Ashwin Prakash
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Cardiology (S.J.G., A.P., P.J.d.N., R.H.R.), Boston Children's Hospital, MA
| | - Pedro J Del Nido
- Departments of Cardiovascular Surgery (V.G., L.M., A.S., M.A.C., E.E.E., J.D., N.S.C., N.E.S., D.M.H., P.E.H., S.J.G., A.P., P.J.d.N.), Boston Children's Hospital, MA
- Cardiology (S.J.G., A.P., P.J.d.N., R.H.R.), Boston Children's Hospital, MA
| | - Rahul H Rathod
- Cardiology (S.J.G., A.P., P.J.d.N., R.H.R.), Boston Children's Hospital, MA
- Departments of Pediatrics (R.H.R.), Harvard Medical School, Boston, MA
| |
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Frieberg P, Sjöberg P, Hedström E, Carlsson M, Liuba P. In vivo hepatic flow distribution by computational fluid dynamics can predict pulmonary flow distribution in patients with Fontan circulation. Sci Rep 2023; 13:18206. [PMID: 37875552 PMCID: PMC10598063 DOI: 10.1038/s41598-023-45396-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 10/19/2023] [Indexed: 10/26/2023] Open
Abstract
In Fontan patients, a lung deprived of hepatic blood may develop pulmonary arterio-venous malformations (PAVMs) resulting in shunting, reduced pulmonary vascular resistance (PVR) and decreased oxygenation. To provide guidance for corrective invasive interventions, we aimed to non-invasively determine how the hepatic to pulmonary blood flow balance correlates with pulmonary flow, PVR, and with oxygen saturation. Magnetic resonance imaging (MRI) data from eighteen Fontan patients (eight females, age 3-14 years) was used to construct patient-specific computational fluid dynamics (CFD) models to calculate the hepatic to pulmonary blood flow. This was correlated with pulmonary vein flow, simulated PVR and oxygen saturation. Clinical applicability of the findings was demonstrated with an interventional patient case. The hepatic to pulmonary blood flow balance correlated with right/left pulmonary vein flow (R2 = 0.50), left/right simulated PVR (R2 = 0.47), and oxygen saturation at rest (R2 = 0.56). In the interventional patient, CFD predictions agreed with post-interventional MRI measurements and with regressions in the cohort. The balance of hepatic blood to the lungs has a continuous effect on PVR and oxygen saturation, even without PAVM diagnosis. MRI combined with CFD may help in planning of surgical and interventional designs affecting the hepatic to pulmonary blood flow balance in Fontan patients.
Collapse
Affiliation(s)
- Petter Frieberg
- Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden.
| | - Pia Sjöberg
- Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden
| | - Erik Hedström
- Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden
- Diagnostic Radiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden
| | - Marcus Carlsson
- Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden
| | - Petru Liuba
- Department of Clinical Sciences Lund, Pediatric Heart Center, Lund University, Skåne University Hospital, Lund, Sweden
| |
Collapse
|
5
|
Govindarajan V, Marshall L, Sahni A, Cetatoiu M, Eickhoff E, Davee J, St Clair N, Schulz N, Hoganson DM, Hammer PE, Ghelani S, Prakash A, Del Nido PJ, Rathod RH. Impact of Age-related change in Caval Flow Ratio on Hepatic Flow Distribution in Fontan. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.09.06.23295166. [PMID: 37732201 PMCID: PMC10508792 DOI: 10.1101/2023.09.06.23295166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Background The Fontan operation is a palliative technique for patients born with single ventricle heart disease. The superior vena cava (SVC), inferior vena cava (IVC), and hepatic veins are connected to the pulmonary arteries in a total cavopulmonary connection by an extracardiac (EC) conduit or a lateral tunnel (LT) connection. A balanced hepatic flow distribution (HFD) to both lungs is essential to prevent pulmonary arteriovenous malformations and cyanosis. HFD is highly dependent on the local hemodynamics. Objective The effect of age-related changes in caval inflows on HFD was evaluated using cardiac MRI (CMR) data and patient-specific computational fluid dynamics (CFD) modeling. Methods SVC and IVC flow from 414 Fontan patients were collected to establish a relationship between SVC:IVC flow ratio and age. CFD modeling was performed in 60 (30 EC and 30 LT) patient models to quantify the HFD that corresponded to patient ages of 3, 8, and 15 years, respectively. Results SVC:IVC flow ratio inverted at ∼8 years of age, indicating a clear shift to lower body flow predominance. Our data showed that variation of HFD in response to age-related changes in caval inflows (SVC:IVC = 2,1, and 0.5 corresponded to ages 3, 8, and 15+ respectively) was not significant for EC but statistically significant for LT cohorts. For all three caval inflow ratios, a positive correlation existed between the IVC flow distribution to both the lungs and the HFD. However, as the SVC:IVC ratio changed from 2→0.5 (age 3→15+), the correlation's strength decreased from 0.87→0.64, due to potential flow perturbation as IVC flow momentum increased. Conclusion Our analysis provided quantitative insights into the impact of the changing caval inflows on Fontan's long-term HFD, highlighting the importance of including SVC:IVC variations over time to understand Fontan's long-term hemodynamics. These findings broaden our understanding of Fontan hemodynamics and patient outcomes. Clinical Perspective With improvement in standard of care and management of single ventricle patients with Fontan physiology, the population of adults with Fontan circulation is increasing. Consequently, there is a clinical need to comprehend the impact of patient growth on Fontan hemodynamics. Using CMR data, we were able to quantify the relationship between changing caval inflows and somatic growth. We then used patient-specific computational flow modeling to quantify how this relationship affected the distribution of long-term hepatic flow in extracardiac and lateral tunnel Fontan types. Our findings demonstrated the significance of including SVC:IVC changes over time in CFD modeling to learn more about the long-term hemodynamics of Fontan. Fontan surgical approaches are increasingly planned and optimized using computational flow modeling. For a patient undergoing a Fontan procedure, the workflow presented in this study that takes into account the variations in Caval inflows over time can aid in predicting the long-term hemodynamics in a planned Fontan pathway.
Collapse
|
6
|
Timofeeva M, Lav C, Cheung MMH, Ooi A. Numerical simulation of the cavopulmonary connection flow with conduit stenoses of varying configurations. Comput Biol Med 2023; 164:107358. [PMID: 37598480 DOI: 10.1016/j.compbiomed.2023.107358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/18/2023] [Accepted: 08/12/2023] [Indexed: 08/22/2023]
Abstract
The circulation in the total cavopulmonary connection (TCPC) is a low-energy system which operation and efficiency are subjected to multiple factors. Some retrospective studies report that the abnormal narrowing of vessels in the system, i.e. stenosis, is one of the most dangerous geometric factors which can result in heart failure. In the present study, the effect of varying extracardiac conduit (ECC) stenosis on the hemodynamics in a surrogate TCPC model is investigated using high-fidelity numerical simulations. The efficiency of the surrogate TCPC model was quantified according to the power loss, relative perfusion in lungs and the percentage of conduit surface area with abnormally low and high wall shear stress for venous flow. Additionally, the impact of respiration and asymmetry in the stenosis geometry to the system was examined. The results show that the flow in the TCPC model exhibits pronounced unsteadiness even under the steady initial boundary conditions, while the uneven pulmonary flow distribution and the presence of the ECC stenosis amplify the chaotic nature of the flow. Energy efficiency of the system is shown to strongly correlate with amount of vortical structures in the model and their range of scales. Finally, the study demonstrates that the presence of respiration in the model adds to perturbations in the flow which causes increase in the power loss. Results obtained in the study provide valuable insights on how the ECC stenosis effect the flow in the surrogate TCPC model under different flow conditions.
Collapse
Affiliation(s)
- Mariia Timofeeva
- The Faculty of Engineering and Information Technology, The University of Melbourne, 700 Swanston Street, Carlton, VIC, 3053, Australia.
| | - Chitrarth Lav
- The Faculty of Engineering and Information Technology, The University of Melbourne, 700 Swanston Street, Carlton, VIC, 3053, Australia; Scuderia AlphaTauri F1, Bicester, OX26 4LD, United Kingdom
| | - Michael M H Cheung
- Department of Cardiology, Royal Children's Hospital, Melbourne, Australia; Heart Research Group, Murdoch Children's Research Institute, Melbourne, Australia; Department of Paediatrics, The University of Melbourne, VIC, 3052, Australia
| | - Andrew Ooi
- The Faculty of Engineering and Information Technology, The University of Melbourne, 700 Swanston Street, Carlton, VIC, 3053, Australia
| |
Collapse
|
7
|
Thermal and Postural Effects on Fluid Mixing and Irrigation Patterns for Intraventricular Hemorrhage Treatment. Ann Biomed Eng 2023; 51:1270-1283. [PMID: 36681748 PMCID: PMC10172237 DOI: 10.1007/s10439-022-03130-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/25/2022] [Indexed: 01/22/2023]
Abstract
Intraventricular hemorrhage is characterized by blood leaking into the cerebral ventricles and mixing with cerebrospinal fluid. A standard treatment method involves inserting a passive drainage catheter, known as an external ventricular drain (EVD), into the ventricle. EVDs have common adverse complications, including the occlusion of the catheter, that may lead to permanent neural damage or even mortality. In order to prevent such complications, a novel dual-lumen catheter (IRRAflow®) utilizing an active fluid exchange mechanism has been recently developed. However, the fluid dynamics of the exchange system have not been investigated. In this study, convective flow in a three-dimensional cerebral lateral ventricle with an inserted catheter is evaluated using an in-house lattice-Boltzmann-based fluid-solid interaction solver. Different treatment conditions are simulated, including injection temperature and patient position. Thermal and gravitational effects on medication distribution are studied using a dye simulator based on a recently-introduced (pseudo)spectral convection-diffusion equation solver. The effects of injection temperature and patient position on catheter performance are presented and discussed in terms of hematoma irrigation, vortical structures, mixing, and medication volume distribution. Results suggest that cold-temperature injections can increase catheter efficacy in terms of dye distribution and irrigation potential, both of which can be further guided by patient positioning.
Collapse
|
8
|
Wei ZA, Fogel MA, Yoganathan AP. Invited Commentary to 'Hemodynamic performance of 16-20mm extracardiac Goretex conduits in adolescent Fontan patients at rest and during simulated exercise'. EUROPEAN JOURNAL OF CARDIO-THORACIC SURGERY : OFFICIAL JOURNAL OF THE EUROPEAN ASSOCIATION FOR CARDIO-THORACIC SURGERY 2022; 63:6998209. [PMID: 36688694 DOI: 10.1093/ejcts/ezad015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/20/2023] [Indexed: 01/24/2023]
Affiliation(s)
- Zhenglun Alan Wei
- Department of Biomedical Engineering, University of Massachusetts Lowell, Lowell, MA, USA
| | - Mark A Fogel
- Department of Cardiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ajit P Yoganathan
- Wallace H. Coulter School of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| |
Collapse
|
9
|
Rijnberg FM, van ‘t Hul LC, Hazekamp MG, van den Boogaard PJ, Juffermans JF, Lamb HJ, Terol Espinosa de Los Monteros C, Kroft LJM, Kenjeres S, le Cessie S, Jongbloed MRM, Westenberg JJM, Roest AAW, Wentzel JJ. Haemodynamic performance of 16-20-mm extracardiac Goretex conduits in adolescent Fontan patients at rest and during simulated exercise. Eur J Cardiothorac Surg 2022; 63:6808623. [PMID: 36342204 PMCID: PMC9972516 DOI: 10.1093/ejcts/ezac522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 10/03/2022] [Accepted: 11/06/2022] [Indexed: 11/09/2022] Open
Abstract
OBJECTIVES To date, it is not known if 16-20-mm extracardiac conduits are outgrown during somatic growth from childhood to adolescence. This study aims to determine total cavopulmonary connection (TCPC) haemodynamics in adolescent Fontan patients at rest and during simulated exercise and to assess the relationship between conduit size and haemodynamics. METHODS Patient-specific, magnetic resonance imaging-based computational fluid dynamic models of the TCPC were performed in 51 extracardiac Fontan patients with 16-20-mm conduits. Power loss, pressure gradient and normalized resistance were quantified in rest and during simulated exercise. The cross-sectional area (CSA) (mean and minimum) of the vessels of the TCPC was determined and normalized for flow rate (mm2/l/min). Peak (predicted) oxygen uptake was assessed. RESULTS The median age was 16.2 years (Q1-Q3 14.0-18.2). The normalized mean conduit CSA was 35-73% smaller compared to the inferior and superior vena cava, hepatic veins and left/right pulmonary artery (all P < 0.001). The median TCPC pressure gradient was 0.7 mmHg (Q1-Q3 0.5-0.8) and 2.0 (Q1-Q3 1.4-2.6) during rest and simulated exercise, respectively. A moderate-strong inverse non-linear relationship was present between normalized mean conduit CSA and TCPC haemodynamics in rest and exercise. TCPC pressure gradients of ≥1.0 at rest and ≥3.0 mmHg during simulated exercise were observed in patients with a conduit CSA ≤ 45 mm2/l/min and favourable haemodynamics (<1 mmHg during both rest and exercise) in conduits ≥125 mm2/l/min. Normalized TCPC resistance correlated with (predicted) peak oxygen uptake. CONCLUSIONS Extracardiac conduits of 16-20 mm have become relatively undersized in most adolescent Fontan patients leading to suboptimal haemodynamics.
Collapse
Affiliation(s)
- Friso M Rijnberg
- Corresponding author. Department of Cardiothoracic surgery, Leiden University Medical Center, Albinusdreef 2, 2333ZA, Leiden, the Netherlands, Telephone number:+31715262348 (F.M. Rijnberg)
| | - Luca C van ‘t Hul
- Department of Cardiology, Biomechanical Engineering, Erasmus MC, Rotterdam, Netherlands
| | - Mark G Hazekamp
- Department of Cardiothoracic Surgery, Leiden University Medical Center, Leiden, Netherlands
| | | | - Joe F Juffermans
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Hildo J Lamb
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | | | - Lucia J M Kroft
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Sasa Kenjeres
- Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology and J.M. Burgers centrum Research School for Fluid Mechanics, Delft, Netherlands
| | - Saskia le Cessie
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, Netherlands
| | - Monique R M Jongbloed
- Department of Cardiology and Anatomy & Embryology, Leiden University Medical Center, Leiden, Netherlands
| | - Jos J M Westenberg
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | | | | |
Collapse
|
10
|
Yi H, Yang Z, Johnson M, Bramlage L, Ludwig B. Hemodynamic characteristics in a cerebral aneurysm model using non-Newtonian blood analogues. PHYSICS OF FLUIDS (WOODBURY, N.Y. : 1994) 2022; 34:103101. [PMID: 36212224 PMCID: PMC9533395 DOI: 10.1063/5.0118097] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/05/2022] [Indexed: 06/16/2023]
Abstract
This study aims to develop an experimentally validated computational fluid dynamics (CFD) model to estimate hemodynamic characteristics in cerebral aneurysms (CAs) using non-Newtonian blood analogues. Blood viscosities varying with shear rates were measured under four temperatures first, which serves as the reference for the generation of blood analogues. Using the blood analogue, particle image velocimetry (PIV) measurements were conducted to quantify flow characteristics in a CA model. Then, using the identical blood properties in the experiment, CFD simulations were executed to quantify the flow patterns, which were used to compare with the PIV counterpart. Additionally, hemodynamic characteristics in the simplified Newtonian and non-Newtonian models were quantified and compared using the experimentally validated CFD model. Results showed the proposed non-Newtonian viscosity model can predict blood shear-thinning properties accurately under varying temperatures and shear rates. Another developed viscosity model based on the blood analogue can well represent blood rheological properties. The comparisons in flow characteristics show good agreements between PIV and CFD, demonstrating the developed CFD model is qualified to investigate hemodynamic factors within CAs. Furthermore, results show the differences of absolute values were insignificant between Newtonian and non-Newtonian fluids in the distributions of wall shear stress (WSS) and oscillatory shear index (OSI) on arterial walls. However, not only does the simplified Newtonian model underestimate WSS and OSI in most regions of the aneurysmal sac, but it also makes mistakes in identifying the high OSI regions on the sac surface, which may mislead the hemodynamic assessment on the pathophysiology of CAs.
Collapse
Affiliation(s)
- Hang Yi
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Zifeng Yang
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Mark Johnson
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Luke Bramlage
- Boonshoft School of Medicine, Wright State University, Dayton, Ohio 45435, USA
| | | |
Collapse
|
11
|
Frieberg P, Aristokleous N, Sjöberg P, Töger J, Liuba P, Carlsson M. Computational Fluid Dynamics Support for Fontan Planning in Minutes, Not Hours: The Next Step in Clinical Pre-Interventional Simulations. J Cardiovasc Transl Res 2021; 15:708-720. [PMID: 34961904 PMCID: PMC9622535 DOI: 10.1007/s12265-021-10198-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 12/13/2021] [Indexed: 12/13/2022]
Abstract
Computational fluid dynamics (CFD) modeling may aid in planning of invasive interventions in Fontan patients. Clinical application of current CFD techniques is however limited by complexity and long computation times. Therefore, we validated a “lean” CFD method to magnetic resonance imaging (MRI) and an “established” CFD method, ultimately aiming to reduce complexity to enable predictive CFD during ongoing interventions. Fifteen Fontan patients underwent MRI for CFD modeling. The differences between lean and established approach, in hepatic and total flow percentage to the left pulmonary artery (%LPA), power loss and relative wall shear stress area were 1.5 ± 4.0%, -0.17 ± 1.1%, -0.055 ± 0.092 mW and 1.1 ± 1.4%. Compared with MRI, the lean and established method showed a bias in %LPA of -1.9 ± 3.4% and -1.8 ± 3.1%. Computation time was for the lean and established approach 3.0 ± 2.0 min and 7.0 ± 3.4 h, respectively. We conclude that the proposed lean method provides fast and reliable results for future CFD support during interventions.
Collapse
Affiliation(s)
- Petter Frieberg
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden.
| | - Nicolas Aristokleous
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden.
- Department of Mechanical & Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus.
| | - Pia Sjöberg
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
| | - Johannes Töger
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
| | - Petru Liuba
- Department of Clinical Sciences Lund, Pediatric Heart Center, Skåne University Hospital, Lund University, Lund, Sweden
| | - Marcus Carlsson
- Department of Clinical Sciences Lund, Clinical Physiology, Skåne University Hospital, Lund University, Lund, Sweden
- Laboratory of Clinical Physiology, NHLBI, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
12
|
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.
Collapse
|
13
|
Iskander A, Bilgi C, Naftalovich R, Hacihaliloglu I, Berkman T, Naftalovich D, Pahlevan N. The Rheology of the Carotid Sinus: A Path Toward Bioinspired Intervention. Front Bioeng Biotechnol 2021; 9:678048. [PMID: 34178967 PMCID: PMC8222608 DOI: 10.3389/fbioe.2021.678048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/05/2021] [Indexed: 11/30/2022] Open
Abstract
The association between blood viscosity and pathological conditions involving a number of organ systems is well known. However, how the body measures and maintains appropriate blood viscosity is not well-described. The literature endorsing the function of the carotid sinus as a site of baroreception can be traced back to some of the earliest descriptions of digital pressure on the neck producing a drop in blood delivery to the brain. For the last 30 years, improved computational fluid dynamic (CFD) simulations of blood flow within the carotid sinus have demonstrated a more nuanced understanding of the changes in the region as it relates to changes in conventional metrics of cardiovascular function, including blood pressure. We suggest that the unique flow patterns within the carotid sinus may make it an ideal site to transduce flow data that can, in turn, enable real-time measurement of blood viscosity. The recent characterization of the PIEZO receptor family in the sinus vessel wall may provide a biological basis for this characterization. When coupled with other biomarkers of cardiovascular performance and descriptions of the blood rheology unique to the sinus region, this represents a novel venue for bioinspired design that may enable end-users to manipulate and optimize blood flow.
Collapse
Affiliation(s)
- Andrew Iskander
- Department of Anesthesiology, Westchester Medical Center, New York Medical College, Valhalla, NY, United States
| | - Coskun Bilgi
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Rotem Naftalovich
- Department of Anesthesiology, New Jersey Medical School, University Hospital, Rutgers University, Newark, NJ, United States.,Medical Corps of the U.S. Army, U.S. Army Medical Department, Fort Sam Houston, San Antonio, TX, United States
| | - Ilker Hacihaliloglu
- Department of Biomedical Engineering, Rutgers School of Engineering, Rutgers University, Piscataway, NJ, United States
| | - Tolga Berkman
- Department of Anesthesiology, New Jersey Medical School, University Hospital, Rutgers University, Newark, NJ, United States
| | - Daniel Naftalovich
- Department of Computational and Mathematical Sciences, California Institute of Technology, Pasadena, CA, United States.,Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Niema Pahlevan
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA, United States.,Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
14
|
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.
Collapse
|
15
|
Is Doppler Echocardiography Adequate for Surgical Planning of Single Ventricle Patients? Cardiovasc Eng Technol 2021; 12:606-617. [PMID: 33931807 DOI: 10.1007/s13239-021-00533-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 03/12/2021] [Indexed: 12/13/2022]
Abstract
PURPOSE Surgical planning has shown great potential for optimizing outcomes for patients affected by single ventricle (SV) malformations. Phase-contrast magnetic resonance imaging (PC-MRI) is the routine technique used for flow acquisition in the surgical planning paradigm. However, PC-MRI may suffer from possible artifacts in certain cases; furthermore, this technology may not be readily available for patients in low and lower-middle-income countries. Therefore, this study aims to investigate the effectiveness of using Doppler echocardiography (echo-Doppler) for flow acquisitions of SV surgical planning. METHODS This study included eight patients whose blood flow data was acquired by both PC-MRI and echo-Doppler. A virtual surgery platform was used to generate two surgical options for each patient: (1) a traditional Fontan conduit and (2) a Y-graft. Computational fluid dynamics (CFD) simulations were conducted using the two flow acquisitions to assess clinically relevant hemodynamic metrics: indexed power loss (iPL) and hepatic flow distribution (HFD). RESULTS Differences exist in flow data acquired by PC-MRI and echo-Doppler, but no statistical significance was obtained. Flow fields, therefore, exhibit discrepancies between simulations using flow acquisitions by PC-MRI and echo-Doppler. In virtual surgery, the two surgical options were ranked based on these metrics. No difference was observed in the ranking of surgical options between using different flow acquisitions. CONCLUSION Doppler echocardiography is an adequate alternative approach to acquire flow data for SV surgical planning. This finding encourages broader usage of SV surgical planning with echo-Doppler when MRI may present artifacts or is not available, especially in low and lower-middle-income countries.
Collapse
|
16
|
Rijnberg FM, van der Woude SFS, van Assen HC, Juffermans JF, Hazekamp MG, Jongbloed MRM, Kenjeres S, Lamb HJ, Westenberg JJM, Wentzel JJ, Roest AAW. Non-uniform mixing of hepatic venous flow and inferior vena cava flow in the Fontan conduit. J R Soc Interface 2021; 18:20201027. [PMID: 33823607 PMCID: PMC8086942 DOI: 10.1098/rsif.2020.1027] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Fontan patients require a balanced hepatic blood flow distribution (HFD) to prevent pulmonary arteriovenous malformations. Currently, HFD is quantified by tracking Fontan conduit flow, assuming hepatic venous (HV) flow to be uniformly distributed within the Fontan conduit. However, this assumption may be unvalid leading to inaccuracies in HFD quantification with potential clinical impact. The aim of this study was to (i) assess the mixing of HV flow and inferior vena caval (IVC) flow within the Fontan conduit and (ii) quantify HFD by directly tracking HV flow and quantitatively comparing results with the conventional approach. Patient-specific, time-resolved computational fluid dynamic models of 15 total cavopulmonary connections were generated, including the HV and subhepatic IVC. Mixing of HV and IVC flow, on a scale between 0 (no mixing) and 1 (perfect mixing), was assessed at the caudal and cranial Fontan conduit. HFD was quantified by tracking particles from the caudal (HFDcaudal conduit) and cranial (HFDcranial conduit) conduit and from the hepatic veins (HFDHV). HV flow was non-uniformly distributed at both the caudal (mean mixing 0.66 ± 0.13) and cranial (mean 0.79 ± 0.11) level within the Fontan conduit. On a cohort level, differences in HFD between methods were significant but small; HFDHV (51.0 ± 20.6%) versus HFDcaudal conduit (48.2 ± 21.9%, p = 0.033) or HFDcranial conduit (48.0 ± 21.9%, p = 0.044). However, individual absolute differences of 8.2–14.9% in HFD were observed in 4/15 patients. HV flow is non-uniformly distributed within the Fontan conduit. Substantial individual inaccuracies in HFD quantification were observed in a subset of patients with potential clinical impact.
Collapse
Affiliation(s)
- Friso M Rijnberg
- Department of Cardiothoracic Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Hans C van Assen
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Joe F Juffermans
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Mark G Hazekamp
- Department of Cardiothoracic Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Monique R M Jongbloed
- Department of Cardiology and Anatomy and Embryology, Leiden University Medical Center, Leiden, The Netherlands
| | - Sasa Kenjeres
- Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology and J. M. Burgerscentrum Research School for Fluid Mechanics, Delft, The Netherlands
| | - Hildo J Lamb
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jos J M Westenberg
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jolanda J Wentzel
- Department of Cardiology, Biomedical Engineering, Erasmus MC, Rotterdam, The Netherlands
| | - Arno A W Roest
- Department of Pediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
17
|
A Simplified In Silico Model of Left Ventricular Outflow in Patients After Transcatheter Mitral Valve Replacement with Anterior Leaflet Laceration. Ann Biomed Eng 2021; 49:1449-1461. [PMID: 33723704 DOI: 10.1007/s10439-021-02740-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/22/2021] [Indexed: 12/13/2022]
Abstract
In silico modeling has been proposed as a tool to simulate left ventricular (LV) outflow tract (LVOT) obstruction in patients undergoing transcatheter mitral valve replacement (TMVR). This study validated a simplified approach to simulate LV outflow hemodynamics in the setting of TMVR with anterior leaflet laceration, a clinical technique used to mitigate the risk of LVOT obstruction. Personalized, 3-dimensional computational fluid dynamics models were developed from computed tomography images of six patients who underwent TMVR with anterior leaflet laceration. LV outflow hemodynamics were simulated using the patient-specific anatomy and the peak systolic flow rate as boundary conditions. The peak outflow velocity, a clinically relevant hemodynamic metric, was extracted from each simulation (vsim-peak) and compared with the clinical measurement from Doppler echocardiography (vclin-peak) for validation. In silico models were successfully developed and implemented for all patients. The pre-processing time was 2 h per model and the simulation could be completed within 3 h. In three patients, the lacerated anterior leaflet exposed open cells of the transcatheter valve to flow. Good agreement was obtained between vsim-peak and vclin-peak (r = 0.97, p < 0.01) with average discrepancies of 5 ± 2% and 14 ± 1% for patients with exposed and unexposed cells of the transcatheter valve, respectively. The proposed in silico modeling paradigm therefore simulated LV outflow hemodynamics in a time-efficient manner and demonstrated good agreement with clinical measurements. Future studies should investigate the ability of this paradigm to support clinical applications.
Collapse
|
18
|
Fluid-Structure Interaction Simulation of an Intra-Atrial Fontan Connection. BIOLOGY 2020; 9:biology9120412. [PMID: 33255292 PMCID: PMC7760396 DOI: 10.3390/biology9120412] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 12/15/2022]
Abstract
Simple Summary A fluid-structure interaction (FSI) simulation of an intra-atrial Fontan connection was performed. Power loss and pressure drop results fluctuated less during the FSI simulation than during the simulation run with rigid walls, but there were no observable differences in time-averaged pressure drop, connection power loss or hepatic flow distribution. These results suggested that employing a rigid wall is a reasonable assumption when evaluating time-averaged hemodynamic quantities of the Fontan connection under resting breath-held flow conditions. Abstract Total cavopulmonary connection (TCPC) hemodynamics has been hypothesized to be associated with long-term complications in single ventricle heart defect patients. Rigid wall assumption has been commonly used when evaluating TCPC hemodynamics using computational fluid dynamics (CFD) simulation. Previous study has evaluated impact of wall compliance on extra-cardiac TCPC hemodynamics using fluid-structure interaction (FSI) simulation. However, the impact of ignoring wall compliance on the presumably more compliant intra-atrial TCPC hemodynamics is not fully understood. To narrow this knowledge gap, this study aims to investigate impact of wall compliance on an intra-atrial TCPC hemodynamics. A patient-specific model of an intra-atrial TCPC is simulated with an FSI model. Patient-specific 3D TCPC anatomies were reconstructed from transverse cardiovascular magnetic resonance images. Patient-specific vessel flow rate from phase-contrast magnetic resonance imaging (MRI) at the Fontan pathway and the superior vena cava under resting condition were prescribed at the inlets. From the FSI simulation, the degree of wall deformation was compared with in vivo wall deformation from phase-contrast MRI data as validation of the FSI model. Then, TCPC flow structure, power loss and hepatic flow distribution (HFD) were compared between rigid wall and FSI simulation. There were differences in instantaneous pressure drop, power loss and HFD between rigid wall and FSI simulations, but no difference in the time-averaged quantities. The findings of this study support the use of a rigid wall assumption on evaluation of time-averaged intra-atrial TCPC hemodynamic metric under resting breath-held condition.
Collapse
|