Coarctation of Aorta Fluid Dynamics after Three-Dimensional Reconstruction: A Case Report and Literature Review

doi:10.21203/rs.3.rs-2716579/v1

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Coarctation of Aorta Fluid Dynamics after Three-Dimensional Reconstruction: A Case Report and Literature Review

https://doi.org/10.21203/rs.3.rs-2716579/v1

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Objective

To investigate the clinical significance of hydrodynamics analysis in diagnosing and treating coarctation of the aorta after three-dimensional reconstruction of CTA.

Methods

The clinical data and imaging data were retrospectively analyzed for a child with coarctation of the aorta and analyzed using computational fluid dynamics combined with relevant literature.

Results

Through the computational fluid dynamics analysis after three-dimensional reconstruction of a child with coarctation of arch, the changes in pressure gradient in the main coarctation section of children's aortic path were deeply discussed and analyzed. The pressure in the coarctation section decreased sharply, the relevant values met the diagnostic criteria, and the hemodynamics could be relieved after surgical anastomosis. Reduced risk of postoperative constriction and postoperative hypertension made surgical intervention feasible. If the hemodynamics of a child could not be alleviated after surgical intervention, interventions such as balloon dilatation or stent could be considered.

Conclusion

Fluid dynamics analysis after three-dimensional reconstruction, under ideal circumstances, could be used to evaluate the overall aortic arch pressure change process more accurately and intuitively with lower cost, less patient pressure, and uncertainty, and has a more comprehensive and systematic guiding significance for the diagnosis and treatment of children with coarctation of the aorta.

Coarctation of the aorta

Congenital heart disease

CTA three-dimensional reconstruction

Computational fluid dynamics.

Coarctation of the Aorta (COA) is the local narrowing of the active lumen caused by the intimal crest, thickening of the system's inner wall, and invagination of aortic wall tissue [1-3]. It accounts for 5%–8% of all congenital heart disease (CHD) and is more prevalent in males [4,5]. The ratio of males to females is 1.27–1.74. The cause of COA is still unclear, but there is mounting evidence that genetic susceptibility plays a role in its occurrence, including family history, Turner syndrome, other genetic syndromes, and NOTCH1 gene mutation. COA is usually considered an isolated cardiac anomaly. The pressure difference between the two sides of the child's constricted segment decreased rapidly, resulting in hypertension at the proximal end of the heart and insufficient blood supply at the distal end. This disease substantially affects the child's health and the family's finances. The diagnosis and treatment of COA is currently a hot spot in clinical research, and there are many un-unified diagnostic criteria, complex preoperative evaluation, high perioperative mortality, and many postoperative complications. For patients with chronic wheezing, shortness of breath, repeated cough, dyspnea, or dysphagia, especially those with poor drug treatment, timely diagnosis and surgical treatment are required [6]. Clinical reports [7,8] have suggested that the clinical symptoms and diagnostic results of the disease are pointedly disjointed, and there is a lack of more systematic and comprehensive tool assistance diagnosis and treatment. Furthermore, according to the article "Analysis of diagnosis and treatment focus of aortic arch dysplasia," jointly released by the Chinese Pediatric Surgical Cardiology Group in 2018 [9]: Although the five commonly used diagnostic methods have advantages, the proximal arch, the distal arch, and the isthmus are less than 60%, 50% and 40% of the diameter of the ascending aorta, respectively. However, it is easy to see that they all rely on the stenosis's diameter for evaluation. These diagnostic methods do not fully consider age, weight, large vessel development, hemodynamics, and other comprehensive conditions, so the accuracy of their criteria is undoubtedly compromised.

Color ultrasound is one of the leading inspection methods of COA [10]. Although it is possible to obtain direct signs of the aortic arch, the quality of ultrasound imaging is affected by the patient's sound transmission conditions. The descending part of the aortic arch and its collateral circulation cannot be displayed clinically in some patients. The operator must check intracardiac abnormalities individually. The technical requirements for the operator are high, leading to a missed diagnosis of aortic arch malformation. Studies have suggested that the missed diagnosis rate of color Doppler ultrasound in COA diagnosis is 5.4%. As color Doppler ultrasound cannot fully display the position relationship between the distal end of the aorta, the constricted segment, and the surrounding blood vessels, the operator must confirm the determination of parameters such as the length and position of the stenosis before operation through other imaging examinations to verify and determine the operation mode. Although pressure data can be directly obtained by vascular catheter pressure measurement, it is not commonly used because it is invasive, requires clinical anesthesia, and is expensive. The catheter and contrast agent can influence hemodynamics. Although MRI can objectively reflect the shape of the aorta, it has high requirements for the heart rate, machine serial number parameters, and ECG gating technology of children, thus developing few institutions. The measured minimum diameter might be missed.

Computed tomographic angiography (CTA) is a method for obtaining intracardiac and extracardiac structural data with extremely spatial resolution using intravenous contrast agents and ionizing radiation [11]. CT allows the evaluation of these structures in 2D and provides the ability to reconstruct 3D data. For patients with poor preoperative arch imaging, CT angiography can be an excellent tool for surgical planning because CT imaging does not produce apparent artifacts on metal objects. This finding is useful for the foot arch imaging of patients who have previously used constriction stents [12]. The guide then clearly pointed out the importance of fluid mechanics at constriction but provided no other analysis methods or strategies.

An image-based computational fluid dynamics (CFD) approach based on Navier Stokes equations is therefore proposed and expected to solve, at source, the current state of the art in terms of the multiplicity of diagnostic criteria for this condition, diversity of treatment modalities, leading to "off" clinical diagnosis and treatment [13]. For example, preoperative diagnosis of aortic arch dysplasia without the need for severing anastomosis surgery after intraoperative release. Intraoperative anastomotic vascular tone is high and must be re-blocked by adding a vascular patch [14]. Postoperative color ultrasound has a significant difference but no clinical manifestations, how to decide whether to re-intervention, and other clinical problems. It is also expected to accurately predict the pressure drop [15,16]. Furthermore, image-based CFD analysis of patient-specific hemodynamics may have relevance for predicting posttreatment hemodynamics and altered hemodynamics versus long-term outcomes in patients with pathological effects on the aorta [17-19]. Therefore, the present study addressed the clinical problem that preoperative diagnosis of COA provides limited information for comprehensive preoperative evaluation.

1.1 Study subjects

We retrospectively collected 40 patients of Group 1 and 20 patients of Group 2 with normal aortic arch who were hospitalized and operated on at the Department of cardiovascular diagnosis COA in our hospital from March 1, 2017, to February 28, 2021. We then analyzed the imaging findings of the COA arch.

The inclusion criteria for the coarctation group are as follows: 1. The systolic blood pressure of the artery in the upper limbs was higher than that of the artery in the lower extremities; 2. The most stenotic area of the aortic arch under CTA was less than 50% than that of the descending aorta; 3. The pressure difference was more than 50 mmHg at the stenosis on color ultrasound before the operation, and COA was confirmed by surgical treatment.

Inclusion criteria for the normal group: 1. No diagnosis of aortic arch disease using CT or color ultrasound during hospitalization, including lung space-occupying lesions such as lung cysts, lung adenomas, and lung abscesses. Exclusion criteria between the constriction and normal groups: 1. No basic information, such as blood pressure and weight of limbs, was recorded; 2. No consent to participate in the clinical trial and signed consent form for enrollment.

This study was approved by the institutional review board of clinical diagnosis and treatment of aortic arch disease (coarctation, aortic arch dissection, and double aortic arch) (No. (2019) No. (258) of Chongqing Medical University Children's Hospital) and the institutional review board of fluid mechanics of large vessel disease assisted by artificial intelligence (No. (2021) No. (394) of Chongqing Medical University Children's Hospital). Informed consent was obtained from the child's guardian, and signed informed consent was obtained.

1.2 methods

1.2.1 examine the apparatus

Echocardiography: The Ge vivid E9 (General Electric, USA) and the Philips ie 33 (Philips, the Netherlands) multifunctional ultrasound diagnostic instruments with probe frequencies of 1.7–3.3 MHz and 1–5 MHz, respectively, were used in this study. The pressure order difference (PspG) across the aortic arch stenosis was recorded.

CTA examination: Dexmedetomidine nasal sedation was performed at the Department of Anesthesiology for children who could not cooperate, using the Philips brilliance ICT machine with a scanning range from the lower neck to the diaphragmatic level. Scanning parameters: tube voltage 80–100 kV, automatic adjustment of tube current, 5.0-mm slice thickness, 5.0-mm slice spacing, and 1.0-mm slice thickness for image reconstruction. For enhanced scanning, high-voltage syringes were used to inject iodinated contrast medium (2 mL/kg body mass, 2 mL/s) through the hand and dorsal foot vein; 2-phase scans were performed at 15–30 s and 50–60 s after drug administration.

1.2.2 hydrodynamic examination method

The recently developed 3D printing technology can reconstruct cardiac vascular models by postprocessing raw DICOM data from CT or MRI. Image postprocessing techniques such as thoracic large vessel volume reproduction (VR) and maximum density projection (MIP) are used to make the ascending aorta, aortic arch, descending aorta, and thoracic aorta transverse septum lie at their greatest level in oblique sagittal alignment. By stereographically visualizing the location of coarctation and the spatial structure relationship of the vessels in the aortic arch dysplasia and combining with computer technology that can be effectively applied with the formulation of preoperative protocols for precision treatment, hemodynamic signals were simulated on CFD software. The resulting data were compared with those of 3D printed vessels for actual measurement and statistical comparison of vessel pressure in the operating room to analyze their accuracy.

The "distance-pressure" curve along the mid-aortic axis was finally obtained, and the area with the curvature and drop of the hemodynamic curve was determined. The diastolic state of the aorta, including the ascending aorta, aortic arch, and vessels branching from it, as well as the descending aorta, were first segmented from the CTA images. Three-dimensional reconstructions were performed; for the three-dimensional reconstructed figures, a polyhedral grid was generated using the integrated meshing algorithm of star-ccm+ (v.12.06; Siemens PLM Software Inc., Texas, USA).

A hemodynamic simulation of peak systolic aortic blood flow was performed using ANSYS products, and a slip-free boundary condition was applied at the inlet of the aortic geometry, normalized the inlet blood pressure, specified the velocity inlet boundary condition, ran the 3D reconstructed pressure curve change map, obtained the hydrodynamic data of the whole flow domain, and calculated the geometric median and the median axis "distance" length of the irregular topology. The program and calculation formula were written in Python, from 0.5 cm above the aortic valve until the midshaft pressure of the vessel at the perforator diaphragm of the descending aorta changed with distance.

1.3 statistical analysis

SPSS22.0 was used for data analysis, and the measurement data are expressed as mean ± standard deviation. By contrast, the counting data are expressed as a rate, with t-test or χ comparison analysis performed between the normal aortic arch group and the group with COA arch and surgery was performed using t-test, and P < 0.05 was considered statistically significant.

2.1 Basic information

A total of 68 children were included in the coarctation group, including 45 children who met the inclusion criteria. Five children with incomplete basic information were excluded, leaving forty patients in this study. There were 23 males and 17 females with a median age of 9.5 (range 2.2–18.7) months, and 87.5% (35/40) of the infants aged 0–1 years, whereas a total of 20 normal subjects, including 11 males and 9 females, comprised 90% (18/20) of the infants aged 0–1 years.

2.2 Hydrodynamic pressure difference is consistent with the preoperative color ultrasound pressure difference contrast and statistically different from the normal group

There was no significant difference (P > 0.05) in fluid pressure between the 40 patients with coarctation group was 63.1 ± 5.1 mmHg compared with that in the group with coarctation and surgery (64.1 ± 5.2 mmHg), whereas there was a significant difference (P < 0.01 ) in fluid pressure between the 40 patients with COA and the group with coarctation and surgery was (4.4 ± 1.0) mmHg in the group with normal pressure.

2.3 Fluid dynamics based to make the preoperative diagnosis of COA more systematic and comprehensive, which is more beneficial for the evaluation of the condition and guidance of intraoperative surgical choice

A1-A5 are five randomly selected groups of constricted children, Fig. 3 depicts the pressure drop at the maximum of the constriction, which was more than 35 mmHg, and A1 was the most significant, whereas Fig. 2 shows that the morphology of the constricted segment was more pronounced. By contrast, b1-b5 were five randomly selected groups of normal children, and their corresponding pressure difference decreased were all less than 10 mmHg; the constricted group had noticeable fluidic changes in the constricted segment. However, the normal group did not exhibit apparent fluidic pressure changes, and the decrease was relatively flat, as projected on the pressure graph in Fig. 3. As the pressure changed from inlet to outlet, a sharp decrease in the short-distance pressure was observed in the narrowing and surgery group but not in the normal group. The visible morphological manifestations had a link with the statistical data; abstracted morphological data are individualized and systematic through the measurement of the fluid dynamics of the constriction segment, which could better evaluate the patient's constriction segment fluidity data, not only the simple data embodiment, is more comprehensive, system, intuitive embodiment, and to be added, the combination of clinical can give a more accurate assessment of the condition, give different guidance criteria for the late postoperative choice,

CFD—an emerging computer virtual mechanics technique [20]—is used to reconstruct geometric models after processing noninvasively acquired imaging images, perform simulated flow of fluids and obtain patient regions of interest by solving a series of equations, such as coronary artery and hemodynamic parameters in the aorta. The resulting fluid parameters should be used to determine disease severity, and the technology is used in various fields, including water engineering, chemical engineering, civil engineering, and medicine. CFD is also widely used in medical aspects such as the coronary artery, intracranial aneurysm, aortic dissection, and other arterial diseases. In COA diseases, CFD can be performed postprocessing based on CTA to reconstruct the aortic arch model. After fluid simulation, hemodynamic parameters were obtained. Hemodynamic parameters, such as pressure gradient and wall shear force gradient, play a noninvasive advantage over cardiac catheters, guiding diagnosis and determining treatment modality. Briefly, the imaging department reported on a narrow diameter and sometimes provided a narrow segment length, and the extent of resection was empirically analyzed using the master knife on CT film.

Intraoperatively, the external diameters were all thick, and after some resection, the internal diameters remained small. There was a reduction in tension bleeding but a little reduction in fear of restenosis. As the existing preoperative imaging report content is too few, diagnostic criteria and research usually focus on the "number" of aortic dysplasia, and it is possible to describe the parameters of a large number of aortic integrals. CFD can be used as an essential description to solve the current problem as it has largely replaced geometrical "algorithms" after the study of angles and proportions, which could not comprehensively reflect the whole picture of aortic dysplasia.

Moreover, the current clinical database of the accuracy of CFD application is still scarce, and little is known about it nationally [21], and the calculation of the pressure gradient at the constriction by CFD using MRI images was performed in Germany in 2015 [18]. Let us consider the technology's far-reaching and detectable value, with CTA performed more often in domestic children due to MRI machines' self-contained fluid analysis software and younger infants and young children's MRI suffers from heart rate and examination time. The CTA machine is incapable of hydrodynamic analysis, so it must be self-developed.

Image-based CFD is a promising approach; however, most of these methods are still in a purely academic state of research, and currently, whether image-based CFD applies to a wide range of cardiovascular diseases, such as abdominal aortic or cerebral aneurysms, congenital and acquired valvular heart diseases, and different CHDs, is under intense investigation [22, 23]. Therefore, through the analysis of fluid hemodynamics after three-dimensional reconstruction of CTA in 40 children with aortic arch constriction and 20 normal subjects in the clinic, from the fluidic diagram and pressure graph, we could have a good sight of various parameters in the patient's constriction, and in-depth analysis and exploration of this child. The diagnosis could be further guided by local hydrodynamic changes and the pattern of change in the coarctation pressure along with the course of the aortic arch in children. The rapid pressure decrease in the constricted segment because of the influence of the coarctation and the provision of its specific parameters are beneficial to our preoperative simulation of the surgical process of the constricted segment, to evaluate the feasibility of a certain surgical way for individual constriction, to evaluate whether the different postoperative hemodynamics are significantly alleviated, to achieve therapeutic purposes, and also to make a more systematic and comprehensive diagnosis of the disease.

However, this technology is in its infancy in the country and has seldom been applied to COA in the clinic, which is a new guide for future diagnosis and treatment of cardiovascular-related diseases. The current guideline diagnostic criteria are admittedly able to define the morphological and developmental "phenomenon" of aortic arch dysplasia, but the subject group hopes to elaborate on the physiological "nature" of aortic arch dysplasia from the hydrodynamic level. CFD has gradually evolved from a preclinical approach to a mode of consideration for human clinical applications, leading to a better understanding of the pathophysiology of the disease by mimicking blood flow-related processes, with significant effects on the formulation and modification of treatment options.

The shortcomings of the present study are that the established database of this study was temporarily insufficient to formulate new diagnostic criteria. Fluidics was still an exploratory and apparent description in terms of the diagnostic treatment of COA, and the problems remained in terms of the accuracy of CFD simulation, including how to obtain more accurate geometric models, the solid-fluid coupling between the blood and the vessel wall, more accurate boundary conditions, and more advanced algorithms. The wall accuracy of vessel models acquired with CT images would be limited by the image resolution, which in turn limits the accuracy of using flow solid coupling methods to calculate the dynamic changes of the vessel wall. The accuracy of the inlet boundary conditions significantly affects the simulation results, so it is critical to improve the measurement accuracy of the aortic inlet blood flow parameters. For simulation algorithms, computational time costs must be decreased while increasing their computational precision to comply with the original intention of rapidly implementing personalized diagnostics and adjuvant treatments for specific patients in the clinic, which currently faces many challenges to move away from the clinic.

In summary, this study found good agreement between the diagnostic treatment of COA based on CFD and methods of imaging analysis in the clinic; However, CFD has the advantage that imaging does not have much and has a broader range of applications. For children with COA, it is possible to assess the overall aortic arch pressure change more accurately and intuitively at a lower cost, with less patient stress and less uncertainty. The objective preoperative assessment of aortic arch diameter and fluid mechanics would benefit the choice of preoperative procedure and the prevention of postoperative complications.

COA

Coarctation of the Aorta

Computed tomography

CHD

Congenital heart disease

Three-Dimensional

CTA

CT Angiography

CFD

Computational fluid dynamics.

Acknowledgements

I would like to thank the Children's Hospital Affiliated to Chongqing Medical University and the Cardiovascular Department for giving me so much advice and assistance. I also want to thank all the teachers and classmates, as well as my parents and family for their companionship, support, and care.

Authors’ contributions

YangDa Ou, the first author, is the design of the work, the acquisition, analysis, interpretation of data, drafts the work and substantively revises it. Bo Pan, the second author, substantively revises it. Tiewei Lv, the third author, gives some suggestions for this work. Lifei Liu, the fourth author, gives some suggestions for this work. Jie Tian and Xin Jin, the corresponding authors, are the design of the work, drafts the work and substantively revises it, approves the submitted version. All authors read and approved the final manuscript.

Funding

CQMU Program for Youth Innovation in Future Medicine, (2022, W0204); Special Project of Intelligent Medicine for postgraduates of CQMU.（No. ZHYX202122）.

Availability of data and materials

The data and materials in the manuscript are available, and the original data for the relevant results is owned by myself and can be contacted if it’s needed.

Ethics approval and consent to participate

This research received ethical approval and consent. And it didn’t require the approval of an ethics committee.

Consent for publication

All children’ information contained in this manuscript has been published with the consent of their parents.

Competing interests

The authors declare that they have no competing interests.

Karaosmanoglu AD, Khawaja RD, Onur MR, et al. CT and MRI of aortic coarctation: pre- and postsurgical findings. AJR Am J Roentgenol, 2015,204(3):W224-233. DOI: 10.2214/AJR.14.12529.
Nigro G, Russo V, Rago A, et al. Heterogeneity of ventricular repolarization in newborns with severe aortic coarctation. Pediatr Cardiol, 2012,33(2):302-306. DOI: 10.1007/s00246-011-0132-4.
Xu J, Zhao H, Wang X, et al. Accuracy, image quality, and radiation dose of prospectively ECG-triggered high-pitch dual-source CT angiography in infants and children with complex coarctation of the aorta. Acad Radiol, 2014,21(10):1248-1254. DOI: 10.1016/j.acra.2014.04.019.
Baumgartner H, Bonhoeffer P, De Groot NM, et al. ESC Guidelines for the management of grown-up congenital heart disease (new version 2010). Eur Heart J, 2010,31(23):2915-2957. DOI: 10.1093/eurheartj/ehq249.
Singh S, Hakim FA, Sharma A, et al. Hypoplasia, pseudocoarctation and coarctation of the aorta - a systematic review. Heart Lung Circ, 2015,24(2):110-118. DOI: 10.1016/j.hlc.2014.08.006.
Yang Y, Jin X, Pan Z, Li Y, Wu C. Diagnosis and surgical repair of congenital double aortic arch in infants. J Cardiothorac Surg. 2019;14(1):160. Published 2019 Sep 9. doi:10.1186/s13019-019-0976-x.
Wu Y, Li J, Wu C, et al. Diagnosis and Surgical Repair for Coarctation of the Aorta With Intracardiac Defects: A Single Center Experience Based on 93 Infants. Front Pediatr, 2020,8:49. DOI: 10.3389/fped.2020.00049.
Goubergrits L, Riesenkampff E, Yevtushenko P, et al. MRI-based computational fluid dynamics for diagnosis and treatment prediction: clinical validation study in patients with coarctation of aorta[J]. J Magn Reson Imaging, 2015,41(4):909-916. DOI: 10.1002/jmri.24639.
Wu J, Lu AD, Zhang LP, Zuo YX, Jia YP. Zhonghua Xue Ye Xue Za Zhi. 2019;40(1):52-57. doi:10.3760/cma.j.issn.0253-2727.2019.01.010
Vigneswaran TV, Bellsham-Revell HR, Chubb H, et al. Early Postnatal Echocardiography in Neonates with a Prenatal Suspicion of Coarctation of the Aorta. Pediatr Cardiol, 2020,41(4):772-780. DOI: 10.1007/s00246-020-02310-5.
Nie P, Wang X, Cheng Z, et al. The value of low-dose prospective ECG-gated dual-source CT angiography in the diagnosis of coarctation of the aorta in infants and children. Clin Radiol, 2012,67(8):738-745. DOI: 10.1016/j.crad.2011.12.007.
Gach P, Dabadie A, Sorensen C, et al. Multimodality imaging of aortic coarctation: From the fetus to the adolescent[J]. Diagn Interv Imaging, 2016,97(5):581-590. DOI: 10.1016/j.diii.2016.03.006.
Sisli E, Kalin S, Tuncer ON, et al. Comparison Between Nomograms Used to Define Pediatric Aortic Arch Hypoplasia: Retrospective Evaluation Among Patients Less Than 1 Year Old with Coarctation of the Aorta. Pediatric Cardiology, 2019,22(5):321-329.
Tsang V, Haapanen H, Neijenhuis R. Aortic Coarctation/Arch Hypoplasia Repair: How Small Is Too Small. Seminars in Thoracic & Cardiovascular Surgery Pediatric Cardiac Surgery Annual, 2019, 22(7):10-13.
LaDisa JF, Figueroa CA, Vignon-Clementel IE, et al. Computational simulations for aortic coarctation: representative results from a sampling of patients. J Biomechan Eng 2011; 133: 091008– 1–9.
Goubergrits L, Mevert R, Yevtushenko P, et al. The impact of MRI-based inflow for the hemodynamic evaluation of aortic coarctation. Ann Biomed Eng 2013; 41: 2575– 2587.
LaDisa JF, Taylor CA, Feinstein JA. Aortic coarctation: recent developments in experimental and computational methods to assess treatments for this simple condition. Prog Pediatr Cardiol 2010; 30: 45– 49.
Midulla M, Moreno R, Baali A, et al. Haemodynamic imaging of thoracic stent-grafts by computational fluid dynamics (CFD): presentation of a patient-specific method combining magnetic resonance imaging and numerical simulations. Eur Radiol 2012; 22: 2094– 2102.
Vergara C, Viscardi F, Antiga L, Luciani GB. Influence of bicuspid valve geometry on ascending aortic fluid dynamics: a parametric study. Artif Organs 2012; 36: 368– 378.
Shepherd B, Abbas A, McParland P, et al. MRI in adult patients with aortic coarctation: diagnosis and follow-up. Clin Radiol, 2015,70(4):433-445. DOI: 10.1016/j.crad.2014.12.005.
Schubert C, J Bruning, Goubergrits L, et al. Assessment of hemodynamic responses to exercise in aortic coarctation using MRI-ergometry in combination with computational fluid dynamics. Scientific Reports. 2020, 10(6):18894-18906.
Senko I, Shatokhin A, Bishnoi I, et al. Intraoperative Rupture Cerebral Aneurysm and Computational Flow Dynamics. Asian J Neurosurg, 2018,13(2):496-498. DOI: 10.4103/ajns.AJNS_359_16.
Hellmeier F, Nordmeyer S, Yevtushenko P, et al. Hemodynamic Evaluation of a Biological and Mechanical Aortic Valve Prosthesis Using Patient-Specific MRI-Based CFD. Artif Organs, 2018,42(1):49-57. DOI: 10.1111/aor.12955.

No competing interests reported.

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Version 1

posted

You are reading this latest preprint version

Coarctation of Aorta Fluid Dynamics after Three-Dimensional Reconstruction: A Case Report and Literature Review

Status:

Version 1

Abstract

Objective

Methods

Results

Conclusion

Figures

Introduction

1 Subjects And Methods

1.1 Study subjects

1.2 methods

1.2.1 examine the apparatus

1.2.2 hydrodynamic examination method

1.3 statistical analysis

2 Results

2.1 Basic information

2.2 Hydrodynamic pressure difference is consistent with the preoperative color ultrasound pressure difference contrast and statistically different from the normal group

2.3 Fluid dynamics based to make the preoperative diagnosis of COA more systematic and comprehensive, which is more beneficial for the evaluation of the condition and guidance of intraoperative surgical choice

3 Discussion

Abbreviations

Declarations

References

Additional Declarations

Status:

Version 1