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Sahni A, Marshall L, Cetatoiu MA, Davee J, Schulz N, Eickhoff ER, St Clair N, Ghelani S, Prakash A, Hammer PE, Hoganson DM, Del Nido PJ, Rathod RH, Govindarajan V. Biomechanical Analysis of Age-Dependent Changes in Fontan Power Loss. Ann Biomed Eng 2024; 52:2440-2456. [PMID: 38753109 DOI: 10.1007/s10439-024-03534-9] [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: 11/08/2023] [Accepted: 05/02/2024] [Indexed: 08/17/2024]
Abstract
The hemodynamics in Fontan patients with single ventricles rely on favorable flow and energetics, especially in the absence of a subpulmonary ventricle. Age-related changes in energetics for extracardiac and lateral tunnel Fontan procedures are not well understood. Vorticity (VOR) and viscous dissipation rate (VDR) are two descriptors that can provide insights into flow dynamics and dissipative areas in Fontan pathways, potentially contributing to power loss. This study examined power loss and its correlation with spatio-temporal flow descriptors (vorticity and VDR). Data from 414 Fontan patients were used to establish a relationship between the superior vena cava (SVC) to inferior vena cava (IVC) flow ratio and age. Computational flow modeling was conducted for both extracardiac conduits (ECC, n = 16) and lateral tunnels (LT, n = 25) at different caval inflow ratios of 2, 1, and 0.5 that corresponded with ages 3, 8, and 15+. In both cohorts, vorticity and VDR correlated well with PL, but ECC cohort exhibited a slightly stronger correlation for PL-VOR (>0.83) and PL-VDR (>0.89) than that for LT cohort (>0.76 and > 0.77, respectively) at all ages. Our data also suggested that absolute and indexed PL increase (p < 0.02) non-linearly as caval inflow changes with age and are highly patient-specific. Comparison of indexed power loss between our ECC and LT cohort showed that while ECC had a slightly higher median PL for all 3 caval inflow ratio examined (3.3, 8.3, 15.3) as opposed to (2.7, 7.6, 14.8), these differences were statistically non-significant. Lastly, there was a consistent rise in pressure gradient across the TCPC with age-related increase in IVC flows for both ECC and LT Fontan patient cohort. Our study provided hemodynamic insights into Fontan energetics and how they are impacted by age-dependent change in caval inflow. This workflow may help assess the long-term sustainability of the Fontan circulation and inform the design of more efficient Fontan conduits.
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Affiliation(s)
- A Sahni
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - L Marshall
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - M A Cetatoiu
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - J Davee
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - N Schulz
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - E R Eickhoff
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - N St Clair
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - S Ghelani
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - A Prakash
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - P E Hammer
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - D M Hoganson
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - P J Del Nido
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - R H Rathod
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Vijay Govindarajan
- Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA.
- Department of Surgery, Harvard Medical School, Boston, MA, USA.
- Department of Internal Medicine (Cardiology), The University of Texas Health Science Center at Houston, Houston, TX, USA.
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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.
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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
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Devlin C, Tomov ML, Chen H, Nama S, Ali S, Neelakantan S, Avazmohammadi R, Dasi LP, Bauser-Heaton HD, Serpooshan V. Patient-specific 3D in vitro modeling and fluid dynamic analysis of primary pulmonary vein stenosis. Front Cardiovasc Med 2024; 11:1432784. [PMID: 39026997 PMCID: PMC11254695 DOI: 10.3389/fcvm.2024.1432784] [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: 05/14/2024] [Accepted: 06/10/2024] [Indexed: 07/20/2024] Open
Abstract
Introduction Primary pulmonary vein stenosis (PVS) is a rare congenital heart disease that proves to be a clinical challenge due to the rapidly progressive disease course and high rates of treatment complications. PVS intervention is frequently faced with in-stent restenosis and persistent disease progression despite initial venous recanalization with balloon angioplasty or stenting. Alterations in wall shear stress (WSS) have been previously associated with neointimal hyperplasia and venous stenosis underlying PVS progression. Thus, the development of patient-specific three-dimensional (3D) in vitro models is needed to further investigate the biomechanical outcomes of endovascular and surgical interventions. Methods In this study, deidentified computed tomography images from three patients were segmented to generate perfusable phantom models of pulmonary veins before and after catheterization. These 3D reconstructions were 3D printed using a clear resin ink and used in a benchtop experimental setup. Computational fluid dynamic (CFD) analysis was performed on models in silico utilizing Doppler echocardiography data to represent the in vivo flow conditions at the inlets. Particle image velocimetry was conducted using the benchtop perfusion setup to analyze WSS and velocity profiles and the results were compared with those predicted by the CFD model. Results Our findings indicated areas of undesirable alterations in WSS before and after catheterization, in comparison with the published baseline levels in the healthy in vivo tissues that may lead to regional disease progression. Discussion The established patient-specific 3D in vitro models and the developed in vitro-in silico platform demonstrate great promise to refine interventional approaches and mitigate complications in treating patients with primary PVS.
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Affiliation(s)
- Christian Devlin
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Martin L. Tomov
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Huang Chen
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Sindhu Nama
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Siraj Ali
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Sunder Neelakantan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
| | - Reza Avazmohammadi
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
- J. Mike Walker ‘66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, United States
- School of Engineering Medicine, Texas A&M University, Houston, TX, United States
| | - Lakshmi Prasad Dasi
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
| | - Holly D. Bauser-Heaton
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Children’s Healthcare of Atlanta, Atlanta, GA, United States
- Sibley Heart Center, Children’s Healthcare of Atlanta, Atlanta, GA, United States
| | - Vahid Serpooshan
- Wallace H. Coulter Department of Biomedical Engineering, Emory University School of Medicine and Georgia Institute of Technology, Atlanta, GA, United States
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Children’s Healthcare of Atlanta, Atlanta, GA, United States
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Moon J, Lancaster T, Sood V, Si MS, Ohye RG, Romano JC. Long-term impact of anatomic subtype in hypoplastic left heart syndrome after Fontan completion. J Thorac Cardiovasc Surg 2024; 168:193-201.e3. [PMID: 37951533 DOI: 10.1016/j.jtcvs.2023.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/17/2023] [Accepted: 11/05/2023] [Indexed: 11/14/2023]
Abstract
BACKGROUND Aortic atresia (AA)/mitral stenosis (MS) is a well-known risk factor for survival after Norwood; however, the effect of anatomical subtypes in those who survive surgical palliation is unknown. METHODS We performed a retrospective single-center study of patients with classic hypoplastic left heart syndrome (HLHS) who underwent Fontan at our center between August 1989 and July 2017. Clinical outcomes, as well as ventricular and atrioventricular-valve (AVV) function, were determined for each patient, and the effects of HLHS subtype were estimated using multivariable statistical analyses. RESULTS We included 418 patients with HLHS (AA/mitral atresia [MA] 153, AA/MS 100, aortic stenosis [AS]/MS 154, and AS/MA 11). The median follow-up period was 8.6 (interquartile range, 2.9-15.8) years. Overall transplant-free survival, cumulative incidence of AVV failure, and ventricular failure, which were defined by moderate dysfunction or greater or the necessity of surgical interventions, were 70.1%, 35.9%, and 17.9% at 20 years, respectively. Of the 3 major subtypes, AA/MS was associated with lower survival rate (AA/MA 74.6% vs AS/MS 79.1% vs AA/MS 56.1% at 17 years, P = .04). The subanalysis between AA/MA and AA/MS revealed AA/MS tended to have a greater rate of ventricular failure without a significant difference of AVV failure (AA/MA 11.2% vs AA/MS 26.2% at 17 years, P = .053). CONCLUSIONS The survival risk of the anatomic subtype AA/MS persisted long term after Fontan completion and was likely due to a greater rate of single ventricle rather than AVV failure. These findings suggest that the abnormal pressure overload condition of the hypoplastic left ventricle created by AA/MS has a detrimental effect on single right ventricle function.
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Affiliation(s)
- Jiyong Moon
- Section of Section of Pediatric Cardiac Surgery, Department of Cardiac Surgery, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, Mich.
| | - Timothy Lancaster
- Section of Section of Pediatric Cardiac Surgery, Department of Cardiac Surgery, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, Mich
| | - Vikram Sood
- Section of Section of Pediatric Cardiac Surgery, Department of Cardiac Surgery, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, Mich
| | - Ming-Sing Si
- Pediatric Cardiovascular Surgery, Department of Surgery, University of California Los Angeles Medical Center, Los Angeles, Calif
| | - Richard G Ohye
- Section of Section of Pediatric Cardiac Surgery, Department of Cardiac Surgery, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, Mich
| | - Jennifer C Romano
- Section of Section of Pediatric Cardiac Surgery, Department of Cardiac Surgery, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, Mich
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Szafron JM, Heng EE, Boyd J, Humphrey JD, Marsden AL. Hemodynamics and Wall Mechanics of Vascular Graft Failure. Arterioscler Thromb Vasc Biol 2024; 44:1065-1085. [PMID: 38572650 PMCID: PMC11043008 DOI: 10.1161/atvbaha.123.318239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 03/12/2024] [Indexed: 04/05/2024]
Abstract
Blood vessels are subjected to complex biomechanical loads, primarily from pressure-driven blood flow. Abnormal loading associated with vascular grafts, arising from altered hemodynamics or wall mechanics, can cause acute and progressive vascular failure and end-organ dysfunction. Perturbations to mechanobiological stimuli experienced by vascular cells contribute to remodeling of the vascular wall via activation of mechanosensitive signaling pathways and subsequent changes in gene expression and associated turnover of cells and extracellular matrix. In this review, we outline experimental and computational tools used to quantify metrics of biomechanical loading in vascular grafts and highlight those that show potential in predicting graft failure for diverse disease contexts. We include metrics derived from both fluid and solid mechanics that drive feedback loops between mechanobiological processes and changes in the biomechanical state that govern the natural history of vascular grafts. As illustrative examples, we consider application-specific coronary artery bypass grafts, peripheral vascular grafts, and tissue-engineered vascular grafts for congenital heart surgery as each of these involves unique circulatory environments, loading magnitudes, and graft materials.
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Affiliation(s)
- Jason M Szafron
- Departments of Pediatrics (J.M.S., A.L.M.), Stanford University, CA
| | - Elbert E Heng
- Cardiothoracic Surgery (E.E.H., J.B.), Stanford University, CA
| | - Jack Boyd
- Cardiothoracic Surgery (E.E.H., J.B.), Stanford University, CA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT (J.D.H.)
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6
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Schäfer M, Di Maria MV, Jaggers J, Stone ML, Campbell DN, Ivy DD, Mitchell MB. Hemi-Fontan and bidirectional Glenn operations result in flow-mediated viscous energy loss at the time of stage II palliation. JTCVS OPEN 2023; 16:836-843. [PMID: 38204687 PMCID: PMC10775100 DOI: 10.1016/j.xjon.2023.09.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/24/2023] [Accepted: 09/08/2023] [Indexed: 01/12/2024]
Abstract
Background Superior cavopulmonary connection (SCPC) for stage II palliation of hypoplastic left heart syndrome (HLHS) is achieved most frequently by either a bidirectional Glenn (BDG) or hemi-Fontan (HF) operation. The comparison of flow hemodynamic efficiency at the region of surgical reconstruction and in proximal pulmonary arteries has been evaluated primarily using computational modeling techniques with conflicting reports. The purpose of this descriptive study was to compare flow hemodynamics following stage II (BDG vs HF) using 4-dimensional flow magnetic resonance imaging (4D-Flow MRI) with particular focus on flow-mediated viscous energy loss (EL') under matched hemodynamic conditions. Methods Patients with hypoplastic left heart syndrome (HLHS) who underwent either HF or BDG as part of stage II palliation underwent pre-Fontan 4D-Flow MRI. Patients were matched by the pulmonary vascular resistance index, net superior vena cava (SVC) flow, right pulmonary artery (RPA) and left pulmonary artery (LPA) size, and age. Maximum EL' throughout the cardiac cycle was calculated along the SVC-RPA and SVC-LPA tracts. Results Eight patients who underwent HF as part of their stage II single ventricle palliation were matched with 8 patients who underwent BDG. There were no differences between the 2 groups in median volumetric indices, including end-diastolic volume (P = .278) and end-systolic volume (P = .213). Moreover, no differences were observed in ejection fraction (P = .091) and cardiac index (P = .324). There also were no differences in peak EL' measured along the SVC-RPA tract (median, 0.05 mW for HF vs 0.04 mW for BDG; P = .365) or along the SVC-LPA tract (median, 0.05 mW vs 0.04 mW; P = .741). Conclusions The second stage of surgical palliation of HLHS using either HF or BDG results in similar flow-mediated viscous energy loss throughout the SCPC junction. 4D-Flow MRI and computational methods should be applied together to investigate flow hemodynamic patterns throughout the Fontan palliation and overall efficiency of the Fontan circuit.
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Affiliation(s)
- Michal Schäfer
- Division of Cardiothoracic Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - Michael V. Di Maria
- Division of Pediatric Cardiology, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - James Jaggers
- Division of Cardiothoracic Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - Matthew L. Stone
- Division of Cardiothoracic Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - David N. Campbell
- Division of Cardiothoracic Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - D. Dunbar Ivy
- Division of Pediatric Cardiology, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
| | - Max B. Mitchell
- Division of Cardiothoracic Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colo
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Yang W, Conover TA, Figliola RS, Giridharan GA, Marsden AL, Rodefeld MD. Passive performance evaluation and validation of a viscous impeller pump for subpulmonary fontan circulatory support. Sci Rep 2023; 13:12668. [PMID: 37542111 PMCID: PMC10403595 DOI: 10.1038/s41598-023-38559-y] [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: 02/14/2023] [Accepted: 07/11/2023] [Indexed: 08/06/2023] Open
Abstract
Patients with single ventricle defects undergoing the Fontan procedure eventually face Fontan failure. Long-term cavopulmonary assist devices using rotary pump technologies are currently being developed as a subpulmonary power source to prevent and treat Fontan failure. Low hydraulic resistance is a critical safety requirement in the event of pump failure (0 RPM) as a modest 2 mmHg cavopulmonary pressure drop can compromise patient hemodynamics. The goal of this study is therefore to assess the passive performance of a viscous impeller pump (VIP) we are developing for Fontan patients, and validate flow simulations against in-vitro data. Two different blade heights (1.09 mm vs 1.62 mm) and a blank housing model were tested using a mock circulatory loop (MCL) with cardiac output ranging from 3 to 11 L/min. Three-dimensional flow simulations were performed and compared against MCL data. In-silico and MCL results demonstrated a pressure drop of < 2 mmHg at a cardiac output of 7 L/min for both blade heights. There was good agreement between simulation and MCL results for pressure loss (mean difference - 0.23 mmHg 95% CI [0.24-0.71]). Compared to the blank housing model, low wall shear stress area and oscillatory shear index on the pump surface were low, and mean washout times were within 2 s. This study demonstrated the low resistance characteristic of current VIP designs in the failed condition that results in clinically acceptable minimal pressure loss without increased washout time as compared to a blank housing model under normal cardiac output in Fontan patients.
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Affiliation(s)
- Weiguang Yang
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, USA.
| | - Timothy A Conover
- Departments of Mechanical Engineering, Clemson University, Clemson, SC, USA
| | - Richard S Figliola
- Departments of Mechanical Engineering, Clemson University, Clemson, SC, USA
| | | | - Alison L Marsden
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Mark D Rodefeld
- Section of Cardiothoracic Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, 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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9
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Birla AK, Brimmer S, Short WD, Olutoye OO, Shar JA, Lalwani S, Sucosky P, Parthiban A, Keswani SG, Caldarone CA, Birla RK. Current state of the art in hypoplastic left heart syndrome. Front Cardiovasc Med 2022; 9:878266. [PMID: 36386362 PMCID: PMC9651920 DOI: 10.3389/fcvm.2022.878266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 08/30/2022] [Indexed: 11/29/2022] Open
Abstract
Hypoplastic left heart syndrome (HLHS) is a complex congenital heart condition in which a neonate is born with an underdeveloped left ventricle and associated structures. Without palliative interventions, HLHS is fatal. Treatment typically includes medical management at the time of birth to maintain patency of the ductus arteriosus, followed by three palliative procedures: most commonly the Norwood procedure, bidirectional cavopulmonary shunt, and Fontan procedures. With recent advances in surgical management of HLHS patients, high survival rates are now obtained at tertiary treatment centers, though adverse neurodevelopmental outcomes remain a clinical challenge. While surgical management remains the standard of care for HLHS patients, innovative treatment strategies continue to be developing. Important for the development of new strategies for HLHS patients is an understanding of the genetic basis of this condition. Another investigational strategy being developed for HLHS patients is the injection of stem cells within the myocardium of the right ventricle. Recent innovations in tissue engineering and regenerative medicine promise to provide important tools to both understand the underlying basis of HLHS as well as provide new therapeutic strategies. In this review article, we provide an overview of HLHS, starting with a historical description and progressing through a discussion of the genetics, surgical management, post-surgical outcomes, stem cell therapy, hemodynamics and tissue engineering approaches.
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Affiliation(s)
- Aditya K. Birla
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
| | - Sunita Brimmer
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
- Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, TX, United States
| | - Walker D. Short
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
| | - Oluyinka O. Olutoye
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
| | - Jason A. Shar
- Department of Mechanical Engineering, Kennesaw State University, Marietta, GA, United States
| | - Suriya Lalwani
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
| | - Philippe Sucosky
- Department of Mechanical Engineering, Kennesaw State University, Marietta, GA, United States
| | - Anitha Parthiban
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
- Division of Pediatric Cardiology, Texas Children's Hospital, Houston, TX, United States
| | - Sundeep G. Keswani
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
| | - Christopher A. Caldarone
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
- Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, TX, United States
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
| | - Ravi K. Birla
- Laboratory for Regenerative Tissue Repair, Texas Children's Hospital, Houston, TX, United States
- Center for Congenital Cardiac Research, Texas Children's Hospital, Houston, TX, United States
- Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, TX, United States
- Department of Surgery, Baylor College of Medicine, Houston, TX, United States
- Division of Pediatric Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, United States
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10
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Arcieri L, Colaneri M, Bianco F, Merlino E, Santoro G, Silvano R, Baldinelli A, Pozzi M. Coronary unroofing does not fits all anomalous aortic origin of coronary arteries. J Card Surg 2022; 37:3536-3542. [PMID: 35989538 DOI: 10.1111/jocs.16876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 06/28/2022] [Accepted: 07/22/2022] [Indexed: 12/01/2022]
Abstract
INTRODUCTION Anomalous aortic origin of coronary artery (AAOCA) is the second leading cause of sudden cardiac death in children and young adults. Intramural-interarterial course is the most frequent anatomic variation and coronary unroofing is widest adopted for surgical management. Symptoms recurrence is described regardless of the technique used. This study aims to describe how an anatomic patient-centered approach aimed to restore a normal coronary artery take-off is associated with symptoms resolution. METHODS From 2008 to 2021, 25 patients were operated on for an AAOCA at a median age of 20 years. Nineteen patients had a right AAOCA and six had left AAOCA. Intramural course was present in 18 patients. Seventy-six percent were symptomatic. No episodes of aborted sudden cardiac death before surgery was described in the population. Surgical technique used were coronary unroofing in 18 patients, coronary neo-ostioplasty in 3, coronary Reimplantation in 3, and main pulmonary artery re-location in 1. RESULTS No hospital mortality or reoperation was observed in our experience as well as major complications related to surgery. Mean hospital length of stay was 8.5 days. None of patients reported symptoms recurrence at follow-up. Young athletes returned to play competitive sport. Postoperative computed tomography scan evaluation showed a general improvement of the take-off angle. CONCLUSIONS AAOCA requires a patient anatomic-based surgical management. There is not a single surgical technique that can fits all anatomic subtype of AAOCA. Surgical techniques may be selected on the base of the preoperative images and intraoperative findings. In our experience, this policy is associated with no symptoms recurrence.
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Affiliation(s)
- Luigi Arcieri
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Massimo Colaneri
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Francesco Bianco
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Ettore Merlino
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Gaetano Santoro
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Raffaele Silvano
- Cardiac Perfusion Service, Ospedali Riuniti Ancona, Ancona, Italy
| | - Alessandra Baldinelli
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
| | - Marco Pozzi
- Pediatric Cardiology and Cardiac Surgery Unit, Ospedali Riuniti Ancona, Ancona, Italy
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11
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Salman HE, Kamal RY, Hijazi ZM, Yalcin HC. Hemodynamic and Structural Comparison of Human Fetal Heart Development Between Normally Growing and Hypoplastic Left Heart Syndrome-Diagnosed Hearts. Front Physiol 2022; 13:856879. [PMID: 35399257 PMCID: PMC8984126 DOI: 10.3389/fphys.2022.856879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/02/2022] [Indexed: 11/20/2022] Open
Abstract
Congenital heart defects (CHDs) affect a wide range of societies with an incidence rate of 1.0–1.2%. These defects initiate at the early developmental stage and result in critical health disorders. Although genetic factors play a role in the formation of CHDs, the occurrence of cases in families with no history of CHDs suggests that mechanobiological forces may also play a role in the initiation and progression of CHDs. Hypoplastic left heart syndrome (HLHS) is a critical CHD, which is responsible for 25–40% of all prenatal cardiac deaths. The comparison of healthy and HLHS hearts helps in understanding the main hemodynamic differences related to HLHS. Echocardiography is the most common imaging modality utilized for fetal cardiac assessment. In this study, we utilized echocardiographic images to compare healthy and HLHS human fetal hearts for determining the differences in terms of heart chamber dimensions, valvular flow rates, and hemodynamics. The cross-sectional areas of chamber dimensions are determined from 2D b-mode ultrasound images. Valvular flow rates are measured via Doppler echocardiography, and hemodynamic quantifications are performed with the use of computational fluid dynamics (CFD) simulations. The obtained results indicate that cross-sectional areas of the left and right sides of the heart are similar for healthy fetuses during gestational development. The left side of HLHS heart is underdeveloped, and as a result, the hemodynamic parameters such as flow velocity, pressure, and wall shear stress (WSS) are significantly altered compared to those of healthy hearts.
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Affiliation(s)
- Huseyin Enes Salman
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Reema Yousef Kamal
- Pediatric Cardiology Division, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
| | - Ziyad M. Hijazi
- Sidra Heart Center, Sidra Medicine, Weill Cornell Medical College, Doha, Qatar
| | - Huseyin Cagatay Yalcin
- Biomedical Research Center, Qatar University, Doha, Qatar
- *Correspondence: Huseyin Cagatay Yalcin,
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12
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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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13
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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.
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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
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14
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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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15
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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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16
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Salman HE, Kamal RY, Yalcin HC. Numerical Investigation of the Fetal Left Heart Hemodynamics During Gestational Stages. Front Physiol 2021; 12:731428. [PMID: 34566694 PMCID: PMC8458957 DOI: 10.3389/fphys.2021.731428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 08/17/2021] [Indexed: 11/23/2022] Open
Abstract
Flow-driven hemodynamic forces on the cardiac tissues have critical importance, and have a significant role in the proper development of the heart. These mechanobiological mechanisms govern the cellular responses for the growth and remodeling of the heart, where the altered hemodynamic environment is believed to be a major factor that is leading to congenital heart defects (CHDs). In order to investigate the mechanobiological development of the normal and diseased hearts, identification of the blood flow patterns and wall shear stresses (WSS) on these tissues are required for an accurate hemodynamic assessment. In this study, we focus on the left heart hemodynamics of the human fetuses throughout the gestational stages. Computational fetal left heart models are created for the healthy fetuses using the ultrasound images at various gestational weeks. Realistic inflow boundary conditions are implemented in the models using the Doppler ultrasound measurements for resolving the specific blood flow waveforms in the mitral valve. Obtained results indicate that WSS and vorticity levels in the fetal left heart decrease with the development of the fetus. The maximum WSS around the mitral valve is determined around 36 Pa at the gestational week of 16. This maximum WSS decreases to 11 Pa at the gestational week of 27, indicating nearly three-times reduction in the peak shear stress. These findings reveal the highly dynamic nature of the left heart hemodynamics throughout the development of the human fetus and shed light into the relevance of hemodynamic environment and development of CHDs.
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Affiliation(s)
- Huseyin Enes Salman
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Reema Yousef Kamal
- Pediatric Cardiology Division, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar
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17
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Ahmed Y, Tossas-Betancourt C, van Bakel PAJ, Primeaux JM, Weadock WJ, Lu JC, Zampi JD, Salavitabar A, Figueroa CA. Interventional Planning for Endovascular Revision of a Lateral Tunnel Fontan: A Patient-Specific Computational Analysis. Front Physiol 2021; 12:718254. [PMID: 34489735 PMCID: PMC8418142 DOI: 10.3389/fphys.2021.718254] [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: 05/31/2021] [Accepted: 07/12/2021] [Indexed: 11/21/2022] Open
Abstract
Introduction A 2-year-old female with hypoplastic left heart syndrome (HLHS)-variant, a complex congenital heart defect (CHD) characterized by the underdevelopment of the left ventricle, presented with complications following single ventricle palliation. Diagnostic work-up revealed elevated Fontan pathway pressures, as well as significant dilation of the inferior Fontan pathway with inefficient swirling flow and hepatic venous reflux. Due to the frail condition of the patient, the clinical team considered an endovascular revision of the Fontan pathway. In this work, we performed a computational fluid dynamics (CFD) analysis informed by data on anatomy, flow, and pressure to investigate the hemodynamic effect of the endovascular Fontan revision. Methods A patient-specific anatomical model of the Fontan pathway was constructed from magnetic resonance imaging (MRI) data using the cardiovascular modeling software CardiovasculaR Integrated Modeling and SimulatiON (CRIMSON). We first created and calibrated a pre-intervention 3D-0D multi-scale model of the patient’s circulation using fluid-structure interaction (FSI) analyses and custom lumped parameter models (LPMs), including the Fontan pathway, the single ventricle, arterial and venous systemic, and pulmonary circulations. Model parameters were iteratively tuned until simulation results matched clinical data on flow and pressure. Following calibration of the pre-intervention model, a custom bifurcated endograft was introduced into the anatomical model to virtually assess post-intervention hemodynamics. Results The pre-intervention model successfully reproduced the clinical hemodynamic data on regional flow splits, pressures, and hepatic venous reflux. The proposed endovascular repair model revealed increases of mean and pulse pressure at the inferior vena cava (IVC) of 6 and 29%, respectively. Inflows at the superior vena cava (SVC) and IVC were each reduced by 5%, whereas outflows at the left pulmonary artery (LPA) and right pulmonary artery (RPA) increased by 4%. Hepatic venous reflux increased by 6%. Conclusion Our computational analysis indicated that the proposed endovascular revision would lead to unfavorable hemodynamic conditions. For these reasons, the clinical team decided to forgo the proposed endovascular repair and to reassess the management of this patient. This study confirms the relevance of CFD modeling as a beneficial tool in surgical planning for single ventricle CHD patients.
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Affiliation(s)
- Yunus Ahmed
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI, United States.,Department of Vascular Surgery, Utrecht University, Utrecht, Netherlands
| | | | - Pieter A J van Bakel
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI, United States.,Department of Vascular Surgery, Utrecht University, Utrecht, Netherlands
| | - Jonathan M Primeaux
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - William J Weadock
- Department of Radiology, University of Michigan, Ann Arbor, MI, United States
| | - Jimmy C Lu
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Jeffrey D Zampi
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - Arash Salavitabar
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, United States
| | - C Alberto Figueroa
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States.,Department of Surgery, University of Michigan, Ann Arbor, MI, United States
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18
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Primeaux J, Salavitabar A, Lu JC, Grifka RG, Figueroa CA. Characterization of Post-Operative Hemodynamics Following the Norwood Procedure Using Population Data and Multi-Scale Modeling. Front Physiol 2021; 12:603040. [PMID: 34054563 PMCID: PMC8155503 DOI: 10.3389/fphys.2021.603040] [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] [Received: 09/04/2020] [Accepted: 04/19/2021] [Indexed: 11/22/2022] Open
Abstract
Children with hypoplastic left heart syndrome (HLHS) must undergo multiple surgical stages to reconstruct the anatomy to a sustainable single ventricle system. Stage I palliation, or the Norwood procedure, provides circulation to both pulmonary and systemic vasculature. The aorta is reconstructed and attached to the right ventricle and a fraction of systemic flow is redirected to the pulmonary arteries (PAs) through a systemic-to-PA shunt. Despite abundant hemodynamic data available 4-5 months after Norwood palliation, data is very scarce immediately following stage I. This data is critical in determining post-operative success. In this work, we combined population data and computational fluid dynamics (CFD) to characterize hemodynamics immediately following stage I (post-stage I) and prior to stage II palliation (pre-stage II). A patient-specific model was constructed as a baseline geometry, which was then scaled to reflect population-based morphological data at both time-points. Population-based hemodynamic data was then used to calibrate each model to reproduce blood flow representative of HLHS patients. The post-stage I simulation produced a PA pressure of 22 mmHg and high-frequency oscillations within the flow field indicating highly disturbed hemodynamics. Despite PA mean pressure dropping to 14 mmHg, the pre-stage II model also produced high-frequency flow components and PA wall shear stress increases. These suboptimal conditions may be necessary to ensure adequate PA flow throughout the pre-stage II period, as the shunt becomes relatively smaller compared to the patient's somatic growth. In the future, CFD can be used to optimize shunt design and minimize these suboptimal conditions.
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Affiliation(s)
- Jonathan Primeaux
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Arash Salavitabar
- C.S. Mott Children’s Hospital, University of Michigan Congenital Heart Center, Ann Arbor, MI, United States
| | - Jimmy C. Lu
- C.S. Mott Children’s Hospital, University of Michigan Congenital Heart Center, Ann Arbor, MI, United States
| | | | - C. Alberto Figueroa
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
- Department of Surgery, University of Michigan, Ann Arbor, MI, United States
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19
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Assessment of biventricular hemodynamics and energy dynamics using lumen-tracking 4D flow MRI without contrast medium. J Cardiol 2021; 78:79-87. [PMID: 33536147 DOI: 10.1016/j.jjcc.2021.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 10/25/2020] [Accepted: 01/12/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Biventricular physiological interaction remains a challenging problem in cardiology. We developed a four-dimensional (4D) flow magnetic resonance imaging (MRI) scan and clinically available analysis protocol based on beat tracking of the cardiovascular lumen without contrast medium, which enabled measurement of the biventricular hemodynamics and energetic performance by calculating flow energy loss (EL) and kinetic energy (KE). The aim of this study was to observe the flow patterns and energy dynamics to reveal the physiology of the right and left ventricular systems. METHODS 4D flow MRI studies were performed in 19 healthy volunteers including 11 male and 8 female. The right and left ventricular systems were segmented to visualize the flow patterns and to quantify the hemodynamics and energy dynamics. RESULTS A large vortex was observed in the left ventricle (LV), along the longitudinal axis, during end diastole and early systole. At early systole, the vortex appeared to facilitate smooth ejection with little EL. In contrast, in the right ventricle (RV), there were vortices near the free wall in both the short and long axes during the diastolic filling phase. Mean EL index during a single cardiac cycle in the right and left heart systems was 0.63 ± 0.16 (0.42-0.99) mW/m2, and 1.02 ± 0.26 (0.58-1.58) mW/m2, respectively. EL is inevitable loss caused by the vortex flow to facilitate smooth right and left ventricular function and left-sided EL tended to correlate positively with heart rate and right ventricular stroke volume. Kinetic energy at the aortic valve was influenced by LV end-diastolic volume/stroke volume. No gender difference was observed. CONCLUSIONS The RV appears to function as a regulator of the energy dynamics of the LV system.
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20
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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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21
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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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22
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Balasubramanian S, Joshi A, Lu JC, Agarwal PP. Advances in Noninvasive Imaging of Patients With Single Ventricle Following Fontan Palliation. Semin Roentgenol 2020; 55:320-329. [PMID: 32859348 DOI: 10.1053/j.ro.2020.06.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | - Aparna Joshi
- Departments of Radiology, University of Michigan, Ann Arbor, MI
| | - Jimmy C Lu
- Departments of Pediatrics, University of Michigan, Ann Arbor, MI; Departments of Radiology, University of Michigan, Ann Arbor, MI
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23
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Weixler VHM, Emani SM. Reply: There is no "one-size-fits-all" in Fontan surgery! J Thorac Cardiovasc Surg 2020; 160:e10. [PMID: 32247588 DOI: 10.1016/j.jtcvs.2020.02.098] [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: 02/29/2020] [Accepted: 02/29/2020] [Indexed: 10/24/2022]
Affiliation(s)
- Viktoria H M Weixler
- Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Mass; Department of Congenital Heart Surgery, German Heart Institute, Berlin, Germany
| | - Sitaram M Emani
- Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Mass
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24
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Personalized Interventions: A Reality in the Next 20 Years or Pie in the Sky. Pediatr Cardiol 2020; 41:486-502. [PMID: 32198592 DOI: 10.1007/s00246-020-02303-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 01/17/2020] [Indexed: 12/22/2022]
Abstract
There is no better representation of the need for personalization of care than the breadth and complexity of congenital heart disease. Advanced imaging modalities are now standard of care in the field, and the advancements being made to three-dimensional visualization technologies are growing as a means of pre-procedural preparation. Incorporating emerging modeling approaches, such as computational fluid dynamics, will push the limits of our ability to predict outcomes, and this information may be both obtained and utilized during a single procedure in the future. Artificial intelligence and customized devices may soon surface as realistic tools for the care of patients with congenital heart disease, as they are showing growing evidence of feasibility within other fields. This review illustrates the great strides that have been made and the persistent challenges that exist within the field of congenital interventional cardiology, a field which must continue to innovate and push the limits to achieve personalization of the interventions it provides.
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25
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Si MS, Sood V, Bove E. Commentary: Why use the Y-graft? J Thorac Cardiovasc Surg 2019; 159:662-664. [PMID: 31668532 DOI: 10.1016/j.jtcvs.2019.08.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Ming-Sing Si
- Section of Pediatric Cardiovascular Surgery, Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich.
| | - Vikram Sood
- Section of Pediatric Cardiovascular Surgery, Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich
| | - Edward Bove
- Section of Pediatric Cardiovascular Surgery, Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich
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26
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Diagnostic and prognostic significance of cardiovascular vortex formation. J Cardiol 2019; 74:403-411. [DOI: 10.1016/j.jjcc.2019.05.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 05/07/2019] [Indexed: 12/16/2022]
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27
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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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28
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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: 10] [Impact Index Per Article: 2.0] [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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29
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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: 435] [Impact Index Per Article: 87.0] [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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Corno AF, Owen MJ, Cangiani A, Hall EJC, Rona A. Physiological Fontan Procedure. Front Pediatr 2019; 7:196. [PMID: 31179252 PMCID: PMC6543709 DOI: 10.3389/fped.2019.00196] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/29/2019] [Indexed: 11/13/2022] Open
Abstract
Objective: The conventional Fontan circulation deviates the superior vena cava (SVC = 1/3 of the systemic venous return) toward the right lung (3/5 of total lung volume) and the inferior vena cava (IVC = 2/3 of the systemic venous return) toward the left lung (2/5 of total lung volume). A "physiological" Fontan deviating the SVC toward the left lung and the IVC toward the right lung was compared with the conventional setting by computational fluid dynamics, studying whether this setting achieves a more favorable hemodynamics than the conventional Fontan circulation. Materials and Methods: An in-silico 3D parametric model of the Fontan procedure was developed using idealized vascular geometries with invariant sizes of SVC, IVC, right pulmonary artery (RPA), and left pulmonary artery (LPA), steady inflow velocities at IVC and SVC, and constant equal outflow pressures at RPA and LPA. These parameters were set to perform finite-volume incompressible steady flow simulations, assuming a single-phase, Newtonian, isothermal, laminar blood flow. Numerically converged finite-volume mass and momentum flow balances determined the inlet pressures and the outflow rates. Numerical closed-path integration of energy fluxes across domain boundaries determined the flow energy loss rate through the Fontan circulation. The comparison evaluated: (1) mean IVC pressure; (2) energy loss rate; (3) kinetic energy maximum value throughout the domain volume. Results: The comparison of the physiological vs. conventional Fontan provided these results: (1) mean IVC pressure 13.9 vs. 14.1 mmHg (= 0.2 mmHg reduction); (2) energy loss rate 5.55 vs. 6.61 mW (= 16% reduction); (3) maximum kinetic energy 283 vs. 396 J/m3 (= 29% reduction). Conclusions: A more physiological flow distribution is accompanied by a reduction of mean IVC pressure and by substantial reductions of energy loss rate and of peak kinetic energy. The potential clinical impact of these hemodynamic changes in reducing the incidence and severity of the adverse long-term effects of the Fontan circulation, in particular liver failure and protein-losing enteropathy, still remains to be assessed and will be the subject of future work.
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Affiliation(s)
| | - Matt J. Owen
- University of Leicester, Leicester, United Kingdom
| | - Andrea Cangiani
- School of Mathematical Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Edward J. C. Hall
- School of Mathematical Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Aldo Rona
- University of Leicester, Leicester, United Kingdom
- Department of Engineering, University of Leicester, Leicester, United Kingdom
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31
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Biko DM, Gaynor JW, Partington SL, Harris MA, Whitehead KK, Trusty P, Yoganathan AP, Fogel MA. Relationship of Aortic Stiffness to Exercise and Ventricular Volumes in Single Ventricles. Ann Thorac Surg 2019; 108:574-580. [PMID: 30959013 DOI: 10.1016/j.athoracsur.2019.03.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/24/2019] [Accepted: 03/04/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND Patients with single ventricle (SV) may often undergo aortic reconstruction that creates a stiff large vessel, increasing afterload and affecting exercise performance. The objective of this study was to determine the relationship of pulse wave velocity (PWV) and distensibility in reconstructed and normal aortic arches after Fontan with exercise variables. METHODS PWV and distensibility of the descending aorta at the level of the diaphragm (DAo) were calculated with real-time exercise cardiac magnetic resonance in 48 patients with SV after Fontan (18 after aortic reconstruction; 30 without aortic reconstruction) and compared with metabolic exercise stress test variables. RESULTS PWV was greater in the reconstructed group than in the non-reconstructed group (median 4.4 m/s [range: 2.3 to 9.8 m/s] versus 3.6 [range: 2.6 to 6.3 m/s], respectively, p = 0.003). Statistically significant inverse correlations were found between PWV and end-diastolic, end-systolic, and stroke volumes at rest and at exercise in the reconstructed group. In addition, inverse correlations also existed in the reconstructed group between distensibility of the DAo and the exercise variables such as peak oxygen pulse (R = 0.56, p = 0.02), peak oxygen consumption (R = 0.63, p = 0.008), oxygen consumption at ventilatory anaerobic threshold (R = 0.48, p = 0.04), and peak work (R = 0.54, p = 0.02). Similar correlations were not seen in patients with non-reconstructed aortas. CONCLUSIONS Patients with SV with reconstructed aortas have increased aortic stiffness, increasing afterload on the ventricle. Native DAo stiffness distal to the reconstruction is inversely correlated with exercise performance, presumably to decrease impedance mismatch to maintain homogeneity of the aortic wall. This information suggests a possible mechanism for decreased exercise performance in patients with SV with aortic reconstructions.
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Affiliation(s)
- David M Biko
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
| | - J William Gaynor
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiothoracic Surgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Sara L Partington
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Matthew A Harris
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Kevin K Whitehead
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Phillip Trusty
- Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Ajit P Yoganathan
- Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Mark A Fogel
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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Rai V, Gładki M, Dudyńska M, Skalski J. Hypoplastic left heart syndrome [HLHS]: treatment options in present era. Indian J Thorac Cardiovasc Surg 2019; 35:196-202. [PMID: 33061005 PMCID: PMC7525540 DOI: 10.1007/s12055-018-0742-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 09/02/2018] [Accepted: 09/07/2018] [Indexed: 11/29/2022] Open
Abstract
Hypoplastic left heart syndrome (HLHS) is the most severe form of congenital heart defect (CHD). The first successful intervention for it was undertaken by Norwood in 1983. Since then, there have been much development in the pre, intra, and postoperative treatment option in staged palliative surgical procedures. Early diagnostic management, prenatal interventions, innovative diagnostic methods, constantly modified surgical techniques, and hybridization contribute to a significant progress in treatment options. This will allow for defining an optimal strategy of improving survival and quality of life in HLHS patients. The development of intervention cardiology makes possible the stepwise treatment of the defect with one operation only. The first and third stage may be done by hybrid or interventional methods, then only the second stage of treatment needs to be done surgically. The world experience and all the available literature says that the 1st-stage procedure could be done now safely either directly or with a bridge to Norwood followed by the stage 2 with a Glen or Hemi-Fontan and followed by a Fontan down the lane surgically.
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Affiliation(s)
- Vivek Rai
- Department of Pediatric Cardiac Surgery, Jagiellonian University Children’s Hospital, Ul. Wielicka 265, 30-663 Krakow, Poland
| | - Marcin Gładki
- Department of Pediatric Cardiac Surgery, Jagiellonian University Children’s Hospital, Ul. Wielicka 265, 30-663 Krakow, Poland
| | - Mirosława Dudyńska
- Department of Pediatric Cardiac Surgery, Jagiellonian University Children’s Hospital, Ul. Wielicka 265, 30-663 Krakow, Poland
| | - Janusz Skalski
- Department of Pediatric Cardiac Surgery, Jagiellonian University Children’s Hospital, Ul. Wielicka 265, 30-663 Krakow, Poland
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33
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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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34
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Vu EL, Mossad EB. Less Invasive, More Informative: A New Mathematical Model of Oxygen Kinetics of Bidirectional Glenn Circulation. J Cardiothorac Vasc Anesth 2018. [PMID: 29525194 DOI: 10.1053/j.jvca.2018.01.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Eric L Vu
- Baylor College of Medicine, Division of Pediatric Cardiac Anesthesia, Texas Children's Hospital, Houston, Texas
| | - Emad B Mossad
- Baylor College of Medicine, Division of Pediatric Cardiac Anesthesia, Texas Children's Hospital, Houston, Texas
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35
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Miyazaki S, Miyaji K, Itatani K, Oka N, Goto S, Nakamura M, Kitamura T, Horai T, Sughimoto K, Nakamura Y, Yoshimura N. Surgical strategy for aortic arch reconstruction after the Norwood procedure based on numerical flow analysis. Interact Cardiovasc Thorac Surg 2018; 26:460-467. [PMID: 29049796 DOI: 10.1093/icvts/ivx332] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 09/01/2017] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVES Inefficient aortic flow after the Norwood procedure is known to lead to the deterioration of ventricular function due to an increased cardiac workload. To prevent the progression of aortic arch obstruction, arch reconstruction concomitant with second-stage surgery is recommended. The aim of this study was to determine the indications for reconstruction based on numerical simulation and to reveal the morphology that affects the haemodynamic parameters. METHODS Fifteen patients who underwent the Norwood procedure or arch repair and Damus-Kaye-Stansel anastomosis were enrolled. The pressure gradient in aortic arch was 1.6 ± 3.9 mmHg (ranged from 0 to 12 mmHg) on catheter examination. Six patients who had prominent turbulent flow accompanied with a large flow energy loss index greater than 40 mW/m2 and high wall shear stress greater than 100 Pa underwent arch reconstruction. RESULTS After arch reconstruction, the energy loss index significantly decreased from 88.5 ± 50.0 mW/m2 to 23.1 ± 10.4 mW/m2 (P = 0.026) and wall shear stress significantly decreased from 194.5 ± 87.4 Pa to 60.3 ± 40.5 Pa (P = 0.0062). There were 3 late deaths due to heart failure caused by progressive atrioventricular valve regurgitation during the follow-up period (60 months). The systemic ventricular function was preserved in the remaining patients without any pressure gradients in the arch. CONCLUSIONS Determining the surgical strategy for arch reconstruction based on numerical flow analysis may effectively reduce the ventricular load even if no stenosis or pressure gradients are observed on catheter examination or echocardiography.
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Affiliation(s)
- Shohei Miyazaki
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Kagami Miyaji
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Keiichi Itatani
- Department of Cardiovascular Surgery, Cardiovascular Imaging Research Laboratory, Kyoto Prefectural University of Medicine, Kyoto City, Kyoto, Japan
| | - Norihiko Oka
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Shinji Goto
- Department of Mechanical Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Masanori Nakamura
- Department of Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Aichi, Japan
| | - Tadashi Kitamura
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Tetsuya Horai
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Koichi Sughimoto
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Yuki Nakamura
- Department of Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan
| | - Naoki Yoshimura
- Department of Surgery I, Toyama University School of Medicine, Toyama City, Toyama, Japan
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36
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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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Yang W, Hanley FL, Chan FP, Marsden AL, Vignon-Clementel IE, Feinstein JA. Computational simulation of postoperative pulmonary flow distribution in Alagille patients with peripheral pulmonary artery stenosis. CONGENIT HEART DIS 2017; 13:241-250. [PMID: 29194961 DOI: 10.1111/chd.12556] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 10/24/2017] [Accepted: 10/28/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Up to 90% of individuals with Alagille syndrome have congenital heart diseases. Peripheral pulmonary artery stenosis (PPS), resulting in right ventricular hypertension and pulmonary flow disparity, is one of the most common abnormalities, yet the hemodynamic effects are ill-defined, and optimal patient management and treatment strategies are not well established. The purpose of this pilot study is to use recently refined computational simulation in the setting of multiple surgical strategies, to examine the influence of pulmonary artery reconstruction on hemodynamics in this population. MATERIALS AND METHODS Based on computed tomography angiography and cardiac catheterization data, preoperative pulmonary artery models were constructed for 4 patients with Alagille syndrome with PPS (all male, age range: 0.6-2.9 years), and flow simulations with deformable walls were performed. Surgeon directed virtual surgery, mimicking the surgical procedure, was then performed to derive postoperative models. Postoperative simulation-derived hemodynamics and blood flow distribution were then compared with the clinical results. RESULTS Simulations confirmed substantial resistance, resulting from preoperative severe ostial stenoses, and the use of newly developed adaptive outflow boundary conditions led to excellent agreement with in vivo measurements. Relief of PPS decreased pulmonary artery pressures and improved pulmonary flow distribution both in vivo and in silico with good correlation. CONCLUSIONS Using adaptive outflow boundary conditions, computational simulations can estimate postoperative overall pulmonary flow distribution in patients with Alagille syndrome after pulmonary artery reconstruction. Obstruction relief along with pulmonary artery vasodilation determines postoperative pulmonary flow distribution and newer methods can incorporate these physiologic changes. Evolving blood flow simulations may be useful in surgical or transcatheter planning and in understanding the complex interplay among various obstructions in patients with peripheral pulmonary stenosis.
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Affiliation(s)
- Weiguang Yang
- Department of Pediatrics (Cardiology), Stanford University School of Medicine, Stanford, California, USA
| | - Frank L Hanley
- Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California, USA
| | - Frandics P Chan
- Department of Radiology, Stanford University School of Medicine, Stanford, California, USA
| | - Alison L Marsden
- Department of Pediatrics (Cardiology), Stanford University School of Medicine, Stanford, California, USA.,Department of BioEngineering, Stanford University School of Medicine, Stanford, California, USA
| | - Irene E Vignon-Clementel
- INRIA and Sorbonne Universités UPMC, Univ. Paris 6, Laboratoire Jacques-Louis Lions, Paris, France
| | - Jeffrey A Feinstein
- Department of Pediatrics (Cardiology), Stanford University School of Medicine, Stanford, California, USA.,Department of BioEngineering, Stanford University School of Medicine, Stanford, California, USA
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Brida M, Baumgartner H, Gatzoulis MA, Diller GP. Early mortality and concomitant procedures related to Fontan conversion: Quantitative analysis. Int J Cardiol 2017; 236:132-137. [DOI: 10.1016/j.ijcard.2017.01.111] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 01/22/2017] [Indexed: 11/16/2022]
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Januszewska K, Schuh A, Lehner A, Dalla-Pozza R, Malec E. Lateral Atrial Tunnel Fontan Operation Predisposes to the Junctional Rhythm. Pediatr Cardiol 2017; 38:712-718. [PMID: 28184977 DOI: 10.1007/s00246-017-1571-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 01/19/2017] [Indexed: 11/30/2022]
Abstract
The goal of the study was to compare the early postoperative course after fenestrated lateral atrial tunnel (LT) and non-fenestrated extracardiac conduit (EC) Fontan operation (FO) in a single center where both techniques were parallelly used. Between 2004 and 2012, 56(32.7%) children underwent LT and 113(66.1%) EC FO. The mean age was 3.7 ± 2.9 years and mean weight was 14.6 ± 7.3 kg. The most common malformation was hypoplastic left heart syndrome (50.9%). The general approach was to perform LT in children after hemi-Fontan operation and EC in patients after Glenn anastomosis. Medical records were retrospectively reviewed. The hospital survival was 100%. In EC group, cardiopulmonary bypass time (CPB) was shorter (p = 0.004) and less patients needed aortic cross-clamping (p < 0.001). Children after EC stayed longer in the hospital (p = 0.016) and manifested more often prolonged effusions (p = 0.038). The incidence of all forms of junctional rhythm was higher in the LT group, early postoperatively (p < 0.001), during hospitalization (p = 0.004) and at discharge (p < 0.001). Children after LT required more often temporary pacemaker stimulation (p < 0.001). Patients without postoperative normofrequent sinus rhythm had longer CPB time (p = 0.008) and were more often operated on with aortic cross-clamping (p = 0.028). Lateral atrial tunnel Fontan operation with fenestration facilitates early adaptation to the total passive pulmonary flow, but predisposes the patients to the loss of sinus rhythm. The crucial role in the preservation of sinus rhythm plays the last step of the multistage surgery of the single ventricle malformations, probably not only the surgical technique but also factors associated with the cardiopulmonary bypass.
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Affiliation(s)
- Katarzyna Januszewska
- Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Geb. A1, 48149, Muenster, Germany.
| | - Anna Schuh
- Department of Pediatric Cardiology and Pediatric Intensive Care, Ludwig-Maximilian-University, Klinikum Großhadern, Marchioninistr.15, 81377, Munich, Germany
| | - Anja Lehner
- Department of Pediatric Cardiology and Pediatric Intensive Care, Ludwig-Maximilian-University, Klinikum Großhadern, Marchioninistr.15, 81377, Munich, Germany
| | - Robert Dalla-Pozza
- Department of Pediatric Cardiology and Pediatric Intensive Care, Ludwig-Maximilian-University, Klinikum Großhadern, Marchioninistr.15, 81377, Munich, Germany
| | - Edward Malec
- Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, University Hospital Muenster, Albert-Schweitzer-Campus 1, Geb. A1, 48149, Muenster, Germany
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Hegde S, Hsiao A. Improving the Fontan: Pre-surgical planning using four dimensional (4D) flow, bio-mechanical modeling and three dimensional (3D) printing. PROGRESS IN PEDIATRIC CARDIOLOGY 2016. [DOI: 10.1016/j.ppedcard.2016.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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41
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Bove EL. A career in congenital heart surgery: One surgeon's recollections. PROGRESS IN PEDIATRIC CARDIOLOGY 2016. [DOI: 10.1016/j.ppedcard.2016.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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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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Bae JM, Jeon TY, Kim JS, Kim S, Hwang SM, Yoo SY, Kim JH. Fontan-associated liver disease: Spectrum of US findings. Eur J Radiol 2016; 85:850-6. [PMID: 26971434 DOI: 10.1016/j.ejrad.2016.02.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 01/25/2016] [Accepted: 02/02/2016] [Indexed: 10/22/2022]
Abstract
PURPOSE To describe ultrasonography (US) findings of Fontan-associated liver disease (FALD) and to determine whether screening US examinations can identify FALD before biochemical hepatic dysfunction. METHODS This retrospective study included 55 patients who underwent Fontan procedure over a 20-year period. Hepatobiliary US findings (n=55), CT or MRI findings (n=19), biochemical hepatic function tests (n=49), and histopathological results (n=4) were analyzed. Images were reviewed focusing on the hepatic parenchymal changes, presence of focal lesions, and signs of portal hypertension. RESULTS Hepatic parenchymal changes (either heterogeneous echotexture or surface nodularity) evident on US were present in 67% (37/55) and showed positive correlation with the Fontan duration. Hyper-echoic lesions were noted in 35% (19/55) and showed a predilection for multiplicity, small size, right lobe location, and irregular margin on high-frequency transducer. These lesions were not demonstrated by CT or MRI or by low-frequency transducer. Histopathological results of targeted biopsy for hyper-echoic lesions revealed lesser degree of patchy sinusoidal and portal fibrosis than seen in cases with surface nodularity. Abnormal parenchymal enhancement was commonly seen with CT or MRI in 63% (12/19) and hypervascular nodules in 21% (4/19). Most patients (82%, 40/49) showed normal biochemical hepatic function tests, despite the presence of hepatic parenchymal changes on imaging. CONCLUSION The common US findings of FALD included heterogeneous parenchymal echotexture, surface nodularity, and hyper-echoic lesions. We suggest that hyper-echoic lesions without surface nodularity detected by high-frequency transducer may represent the early stage of fibrosis. US examination may be useful for identifying the progression of FALD before biochemical hepatic dysfunction.
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Affiliation(s)
- Jung Min Bae
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
| | - Tae Yeon Jeon
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea.
| | - Jung Sun Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
| | - Seokhwi Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
| | - Sook Min Hwang
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
| | - So-Young Yoo
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
| | - Ji Hye Kim
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, South Korea
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Adaptive outflow boundary conditions improve post-operative predictions after repair of peripheral pulmonary artery stenosis. Biomech Model Mechanobiol 2016; 15:1345-53. [PMID: 26843118 DOI: 10.1007/s10237-016-0766-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 01/19/2016] [Indexed: 12/21/2022]
Abstract
Peripheral pulmonary artery stenosis (PPS) is a congenital abnormality resulting in pulmonary blood flow disparity and right ventricular hypertension. Despite recent advance in catheter-based interventions, surgical reconstruction is still preferred to treat complex PPS. However optimal surgical strategies remain unclear. It would be of great benefit to be able to predict post-operative hemodynamics to assist with surgical planning toward optimizing outcomes. While image-based computational fluid dynamics has been used in cardiovascular surgical planning, most studies have focused on the impact of local geometric changes on hemodynamic performance. Previous experimental studies suggest morphological changes in the pulmonary arteries not only alter local hemodynamics but also lead to distal pulmonary adaptation. In this proof of concept study, a constant shear stress hypothesis and structured pulmonary trees are used to derive adaptive outflow boundary conditions for post-operative simulations. Patient-specific simulations showed the adaptive outflow boundary conditions by the constant shear stress model to provide better predictions of pulmonary flow distribution than the conventional strategy of maintaining outflow boundary conditions. On average, the relative difference, when compared to the gold standard clinical test, in blood flow distribution to the right lung is reduced from 20 to 4 %. This suggests adaptive outflow boundary conditions should be incorporated into post-operative modeling in patients with complex PPS.
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Poullis M, Pullan M. Mechanism of failure of the Cabrol procedure: A computational fluid dynamic analysis. Med Hypotheses 2015; 85:774-8. [DOI: 10.1016/j.mehy.2015.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 10/06/2015] [Accepted: 10/11/2015] [Indexed: 10/22/2022]
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Di Molfetta A, Pilati M, Gagliardi M, Fresiello L, Amodeo A, Cristofaletti A, Pongiglione G, Ferrari G. Tailoring the hybrid palliation for hypoplastic left heart syndrome: A simulation study using a lumped parameter model. Med Eng Phys 2015. [DOI: 10.1016/j.medengphy.2015.04.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
Although mortality is low after the modified Fontan procedure, there is a significant percentage of patients with prolonged postoperative recovery. The objective of this study is to evaluate the usefulness of postoperative administration of oral sildenafil and inhaled nitric oxide on early postoperative outcome. A prospective interventional and comparison study with a historical cohort was conducted. Between January, 2010 and March, 2013, 16 patients received oral sildenafil during immediate modified Fontan postoperative period. Inhaled nitric oxide was also administered if the patient was kept intubated 12 hours after surgery. Early postoperative outcome was compared with a historical cohort of 32 patients on whom the modified Fontan procedure was performed between March, 2000 and December, 2009. Postoperative administration of sildenafil and nitric oxide had no influence on early postoperative outcome after the modified Fontan procedure in terms of duration of pleural effusions, mechanical ventilation time, length of stay in the ICU, and length of hospital stay.
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Pushparajah K, Wong JK, Bellsham-Revell HR, Hussain T, Valverde I, Bell A, Tzifa A, Greil G, Simpson JM, Kutty S, Razavi R. Magnetic resonance imaging catheter stress haemodynamics post-Fontan in hypoplastic left heart syndrome. Eur Heart J Cardiovasc Imaging 2015; 17:644-51. [PMID: 26188193 DOI: 10.1093/ehjci/jev178] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Accepted: 06/18/2015] [Indexed: 11/13/2022] Open
Abstract
AIMS Exercise limitation is common post-Fontan. Hybrid X-ray and magnetic resonance imaging (XMR) catheterization allows haemodynamic assessment by means of measurement of ventricular volumes and flow in major vessels with simultaneous invasive pressures. We aim to assess haemodynamic response to stress in patients with hypoplastic left heart syndrome (HLHS) post-Fontan. METHODS AND RESULTS Prospective study of 13 symptomatic children (NHYA 2) with HLHS post-Fontan using XMR catheterization. Three conditions were applied: baseline (Stage 1), dobutamine at 10 µg/kg/min (Stage 2), and dobutamine at 20 µg/kg/min (Stage 3). Seven consecutive patients received inhaled nitric oxide (iNO) at peak stress. Control MRI data were from normal healthy adults. In the HLHS patients, baseline mean pulmonary vascular resistance (PVR) was 1.51 ± 0.59 WU m(2) and aortopulmonary collateral flow was 17.7 ± 13.6% of systemic cardiac output. Mean right ventricular end-diastolic pressure was 6.7 ± 2.5 mmHg which did not rise with stress. Cardiac index (CI) increased at Stage 2 in HLHS (40%) and controls (61%) but continued to increase at Stage 3 only in controls (19%) but not in HLHS. The blunted rise in CI in HLHS was due to a continuing fall in end-diastolic volume throughout stress, with no significant change in PVR or CI at peak stress in response to iNO. CONCLUSION Cardiac output post-Fontan in HLHS at peak stress is blunted due to a limitation in preload which is not responsive to inhaled pulmonary vasodilators in the setting of normal PVR.
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Affiliation(s)
- Kuberan Pushparajah
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - James K Wong
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Hannah R Bellsham-Revell
- Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Tarique Hussain
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Israel Valverde
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Aaron Bell
- Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Aphrodite Tzifa
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Gerald Greil
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - John M Simpson
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Shelby Kutty
- University of Nebraska/Creighton University Joint Division of Pediatric Cardiology, Omaha, NE, USA
| | - Reza Razavi
- Division of Imaging Sciences, King's College London BHF Centre, NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Congenital Heart Disease, Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK Paediatric Cardiovascular Sciences, Rayne Institute, King's College London and Evelina London Children's Hospital, Westminster Bridge Road, London SE1 7EH, UK
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Arbia G, Corsini C, Baker C, Pennati G, Hsia TY, Vignon-Clementel IE. Pulmonary Hemodynamics Simulations Before Stage 2 Single Ventricle Surgery: Patient-Specific Parameter Identification and Clinical Data Assessment. Cardiovasc Eng Technol 2015; 6:268-80. [DOI: 10.1007/s13239-015-0212-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 01/10/2015] [Indexed: 10/24/2022]
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Martin MH, Feinstein JA, Chan FP, Marsden AL, Yang W, Reddy VM. Technical feasibility and intermediate outcomes of using a handcrafted, area-preserving, bifurcated Y-graft modification of the Fontan procedure. J Thorac Cardiovasc Surg 2015; 149:239-45.e1. [DOI: 10.1016/j.jtcvs.2014.08.058] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 08/16/2014] [Accepted: 08/23/2014] [Indexed: 11/16/2022]
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