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Katakia YT, Kanduri S, Bhattacharyya R, Ramanathan S, Nigam I, Kuncharam BVR, Majumder S. Angular difference in human coronary artery governs endothelial cell structure and function. Commun Biol 2022; 5:1044. [PMID: 36183045 PMCID: PMC9526720 DOI: 10.1038/s42003-022-04014-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 09/20/2022] [Indexed: 12/03/2022] Open
Abstract
Blood vessel branch points exhibiting oscillatory/turbulent flow and lower wall shear stress (WSS) are the primary sites of atherosclerosis development. Vascular endothelial functions are essentially dependent on these tangible biomechanical forces including WSS. Herein, we explored the influence of blood vessel bifurcation angles on hemodynamic alterations and associated changes in endothelial function. We generated computer-aided design of a branched human coronary artery followed by 3D printing such designs with different bifurcation angles. Through computational fluid dynamics analysis, we observed that a larger branching angle generated more complex turbulent/oscillatory hemodynamics to impart minimum WSS at branching points. Through the detection of biochemical markers, we recorded significant alteration in eNOS, ICAM1, and monocyte attachment in EC grown in microchannel having 60o vessel branching angle which correlated with the lower WSS. The present study highlights the importance of blood vessel branching angle as one of the crucial determining factors in governing atherogenic-endothelial dysfunction. In silico and in vitro investigations reveal angular differences in the blood vessel branching points differentially alter the hemodynamics to impact endothelial structure and function.
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Affiliation(s)
- Yash T Katakia
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India
| | - Satyadevan Kanduri
- Department of Chemical Engineering, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India
| | - Ritobrata Bhattacharyya
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India
| | - Srinandini Ramanathan
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India
| | - Ishan Nigam
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India
| | | | - Syamantak Majumder
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS), Pilani Campus, Pilani, India.
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Chuchalerm N, Sawangtong W, Wiwatanapataphee B, Siriapisith T. Study of Non-Newtonian blood flow - heat transfer characteristics in the human coronary system with an external magnetic field. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2022; 19:9550-9570. [PMID: 35942772 DOI: 10.3934/mbe.2022444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This paper proposes a novel mathematical model of non-Newtonian blood flow and heat transfer in the human coronary system with an external magnetic field. As the blood viscosity is assumed to depend not only on shear rate but also on temperature and magnet strength, the modified Carreau-Yasuda viscosity model is formulated. The computational domain includes the base of the aorta, the right coronary artery, and the left coronary artery, with the left circumflex and left anterior descending arteries. The element-based finite volume method is derived for the solution of the proposed model. Numerical simulations are carried out to investigate the magnetic field effect on the blood flow-heat transfer characteristic in the human coronary system. It is found that the magnetic field has a significant impact on fluid viscosity, leading to enhanced fluid velocity.
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Affiliation(s)
- Nattawan Chuchalerm
- Department of Mathematics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
- Centre of Excellence in Mathematics, Commission on Higher Education, Bangkok 10400, Thailand
| | - Wannika Sawangtong
- Department of Mathematics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
- Centre of Excellence in Mathematics, Commission on Higher Education, Bangkok 10400, Thailand
| | - Benchawan Wiwatanapataphee
- School of Electrical Engineering, Computing and Mathematical Sciences, Curtin University, Perth, WA 6845, Australia
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Owen DG, de Oliveira DC, Neale EK, Shepherd DET, Espino DM. Numerical modelling of blood rheology and platelet activation through a stenosed left coronary artery bifurcation. PLoS One 2021; 16:e0259196. [PMID: 34731193 PMCID: PMC8565790 DOI: 10.1371/journal.pone.0259196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/14/2021] [Indexed: 01/09/2023] Open
Abstract
Coronary bifurcations are prone to atherosclerotic plaque growth, experiencing regions of reduced wall shear stress (WSS) and increased platelet adhesion. This study compares effects across different rheological approaches on hemodynamics, combined with a shear stress exposure history model of platelets within a stenosed porcine bifurcation. Simulations used both single/multiphase blood models to determine which approach best predicts phenomena associated with atherosclerosis and atherothrombosis. A novel Lagrangian platelet tracking model was used to evaluate residence time and shear history of platelets indicating likely regions of thrombus formation. Results show a decrease in area of regions with pathologically low time-averaged WSS with the use of multiphase models, particularly in a stenotic bifurcation. Significant non-Newtonian effects were observed due to low-shear and varying hematocrit levels found on the outer walls of the bifurcation and distal to the stenosis. Platelet residence time increased 11% in the stenosed artery, with exposure times to low-shear sufficient for red blood cell aggregation (>1.5 s). increasing the risk of thrombosis. This shows stenotic artery hemodynamics are inherently non-Newtonian and multiphase, with variations in hematocrit (0.163-0.617) and elevated vorticity distal to stenosis (+15%) impairing the function of the endothelium via reduced time-averaged WSS regions, rheological properties and platelet activation/adhesion.
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Affiliation(s)
- David G. Owen
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Diana C. de Oliveira
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Emma K. Neale
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Duncan E. T. Shepherd
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Daniel M. Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
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Cong M, Zhao H, Dai S, Chen C, Xu X, Qiu J, Qin S. Transient numerical simulation of the right coronary artery originating from the left sinus and the effect of its acute take-off angle on hemodynamics. Quant Imaging Med Surg 2021; 11:2062-2075. [PMID: 33936987 DOI: 10.21037/qims-20-125] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background An anomalous origin of the right coronary artery from the left coronary artery sinus is usually characterized by an acute take-off angle. Most affected patients have no clinical symptoms; however, some patients have decreased blood flow into the right coronary artery during exercise, which can lead to symptoms such as myocardial ischemia. Most researchers who have studied an anomalous origin of the right coronary artery from the left coronary artery sinus have done so through clinical cases. In this study, we used numerical simulation to evaluate the hemodynamics of this condition and the effect of an acute take-off angle on hemodynamic parameters. We expect that the results of this study will help in further understanding the clinical symptoms of this anomaly and the hemodynamic impact of an acute take-off angle. Methods Three-dimensional models were reconstructed based on the computed tomography images from 16 patients with a normal right coronary artery and 26 patients with an anomalous origin of the right coronary artery from the left coronary artery sinus. A numerical simulation of a two-way fluid-structure interaction was executed with ANSYS Workbench software. The blood was assumed to be an incompressible Newtonian fluid, and the vessel was assumed to be an isotropic, linear elastic material. Hemodynamic parameters and the effect of an acute take-off angle were statistically analyzed. Results During the systolic period, the wall pressure in the right coronary artery was significantly reduced in patients with an anomalous origin of the right coronary artery (t =1.32 s, P=0.0001; t =1.34-1.46 s, P<0.0001). The wall shear stress in the abnormal group was higher at the beginning of the systolic period (t =1.24 s, P=0.0473; t =1.26 s, P=0.0193; t =1.28 s, P=0.0441). The acute take-off angle was smaller in patients with clinical symptoms (27.81°±4.406°) than in patients without clinical symptoms (31.86°±2.789°; P=0.017). In the symptomatic group, pressure was negatively correlated with the acute take-off angle (P=0.0185-0.0341, r=-0.459 to -0.4167). Conclusions This study shows that an anomalous origin of the right coronary artery from the left coronary artery sinus causes changes in hemodynamic parameters, and that an acute take-off angle in patients with this anomaly is associated with terminal ischemia of the right coronary artery.
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Affiliation(s)
- Mengyang Cong
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China
| | - Huihui Zhao
- Department of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China.,Center for Medical Engineer Technology Research, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China
| | - Shun Dai
- Department of Radiology, Shanghai Tong Ren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chuanzhi Chen
- Department of Radiology, East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xingming Xu
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Tai'an, China
| | - Jianfeng Qiu
- Department of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China.,Center for Medical Engineer Technology Research, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China
| | - Shengxue Qin
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China
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Bahrami S, Norouzi M. Hemodynamic impacts of hematocrit level by two-way coupled FSI in the left coronary bifurcation. Clin Hemorheol Microcirc 2020; 76:9-26. [DOI: 10.3233/ch-200854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Cardiovascular disease is now under the influence of several factors that encourage researchers to investigate the flow of these vessels. Oscillation influences the blood circulation in the volume of red blood cells (RBC) strongly. Therefore, in this study, its effects have been considered on hemodynamic parameters in the elastic wall and coronary bifurcation. In this study, a 3D geometry of non-Newtonian and pulsatile blood circulation is considered in the left coronary artery bifurcation. The Casson model with various hematocrits is analyzed in elastic and rigid walls. The wall shear stress (WSS) cannot show the stenosis artery alone, therefore, the oscillatory shear index (OSI) is represented as a hemodynamic parameter of WSS individually of time. The results are determined using two-way fluid-structure interaction (FSI) coupling method using an arbitrary Lagrangian-Eulerian method. The most prominent difference in velocity happened in the bifurcation and at hematocrit 30 with yield stress 6.59E-04 Pa. The backflow and vortex flow in the LCx branch grown with increasing shear rates. The likelihood of plaque generation at the ending of the LM branch is observed in hematocrits 10 and 20, while the WSS magnitude is normal in the hematocrit 60 with the greatest yield stress in the bifurcation. The shear stress among the rigid and elastic models is the highest at the ending of the LM branch. The wall shear stress magnitude among the models decreased at most of 24.49% by dividing the flow. Time-independent results for models showed that there is the highest value of OSI at the bifurcation, which then quickly dropped.
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Affiliation(s)
- Saeed Bahrami
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Semnan, Iran
| | - Mahmood Norouzi
- Faculty of Mechanical Engineering, Shahrood University of Technology, Shahrood, Semnan, Iran
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Cong M, Xu X, Qiu J, Dai S, Chen C, Qian X, Zhang H, Qin S, Zhao H. Influence of malformation of right coronary artery originating from the left sinus in hemodynamic environment. Biomed Eng Online 2020; 19:59. [PMID: 32727522 PMCID: PMC7392689 DOI: 10.1186/s12938-020-00804-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 07/23/2020] [Indexed: 11/11/2022] Open
Abstract
Background The anomalous origin of the right coronary artery (RCA) from the left coronary artery sinus (AORL) is one of the abnormal origins of the coronary arteries. Most of these issues rarely have any effects on human health, but some individuals may exhibit symptoms, such as myocardial ischemia or even sudden death. Recently, researchers have investigated the AORL through clinical cases, but studies based on computational fluid dynamics (CFD) have rarely been reported. In this study, the hemodynamic changes between the normal origin of the RCA and the AORL are compared based on numerical simulation results. Methods Realistic three-dimensional (3D) models of the 16 normal right coronary arteries and 26 abnormal origins of the RCAs were constructed, respectively. The blood flow was numerically simulated using the ANSYS software. This study used a one-way fluid–solid coupling finite element model, wherein the blood is assumed to be an incompressible Newtonian fluid, and the vessel is assumed to be made of an isotropic linear elastic material. Results The cross-sectional area differences between the inlet of the normal group and that of the abnormal group were significant (P < 0.0001). Moreover, there were significant differences in the volumetric flow (P = 0.0001) and pressure (P = 0.0002). Positive correlation exists for the ratio of the cross-sectional area of the RCA to the inlet area of the ascending aorta (AAO), and the ratio of the inlet volumetric flow of the RCA to the volumetric flow of the AAO, in the normal (P = 0.0001, r = 0.8178) and abnormal (P = 0.0033, r = 0.6107) groups. Conclusion This study demonstrates that the cross-sectional area of the AORL inlet may cause ischemia symptoms. The results obtained by this study may contribute to the further understanding of the clinical symptoms of the AORL based on the hemodynamics.
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Affiliation(s)
- Mengyang Cong
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Xingming Xu
- Intelligent Equipment College, Shandong University of Science and Technology, Taian, 271016, China
| | - Jianfeng Qiu
- Department of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271016, China.,Center for Medical Engineer Technology Research, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271016, China
| | - Shun Dai
- Department of Radiology, Shanghai Tong Ren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200120, China
| | - Chuanzhi Chen
- Department of Radiology, East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Xiuqing Qian
- Department of Biomedical engineering, Capital Medical University, Beijing, 10060, China
| | - Hongbin Zhang
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Shengxue Qin
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, 266590, China.
| | - Huihui Zhao
- Department of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271016, China. .,Center for Medical Engineer Technology Research, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271016, China.
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Schwarz JCV, van Lier MGJTB, van den Wijngaard JPHM, Siebes M, VanBavel E. Topologic and Hemodynamic Characteristics of the Human Coronary Arterial Circulation. Front Physiol 2020; 10:1611. [PMID: 32038291 PMCID: PMC6989553 DOI: 10.3389/fphys.2019.01611] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 12/23/2019] [Indexed: 11/26/2022] Open
Abstract
Background Many processes contributing to the functional and structural regulation of the coronary circulation have been identified. A proper understanding of the complex interplay of these processes requires a quantitative systems approach that includes the complexity of the coronary network. The purpose of this study was to provide a detailed quantification of the branching characteristics and local hemodynamics of the human coronary circulation. Methods The coronary arteries of a human heart were filled post-mortem with fluorescent replica material. The frozen heart was alternately cut and block-face imaged using a high-resolution imaging cryomicrotome. From the resulting 3D reconstruction of the left coronary circulation, topological (node and loop characteristics), topographic (diameters and length of segments), and geometric (position) properties were analyzed, along with predictions of local hemodynamics (pressure and flow). Results The reconstructed left coronary tree consisted of 202,184 segments with diameters ranging from 30 μm to 4 mm. Most segments were between 100 μm and 1 mm long. The median segment length was similar for diameters ranging between 75 and 200 μm. 91% of the nodes were bifurcations. These bifurcations were more symmetric and less variable in smaller vessels. Most of the pressure drop occurred in vessels between 200 μm and 1 mm in diameter. Downstream conductance variability affected neither local pressure nor median local flow and added limited extra variation of local flow. The left coronary circulation perfused 358 cm3 of myocardium. Median perfused volume at a truncation level of 100 to 200 μm was 20 mm3 with a median perfusion of 5.6 ml/min/g and a high local heterogeneity. Conclusion This study provides the branching characteristics and hemodynamic analysis of the left coronary arterial circulation of a human heart. The resulting model can be deployed for further hemodynamic studies at the whole organ and local level.
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Affiliation(s)
- Janina C V Schwarz
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Monique G J T B van Lier
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | | | - Maria Siebes
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Ed VanBavel
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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Toluey M, Ghaffari S, Tajlil A, Nasiri B, Rostami A. The impact of cigarette smoking on infarct location and in-hospital outcome following acute ST-elevation myocardial infarction. J Cardiovasc Thorac Res 2019; 11:209-215. [PMID: 31579461 PMCID: PMC6759623 DOI: 10.15171/jcvtr.2019.35] [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: 02/20/2019] [Accepted: 07/19/2019] [Indexed: 12/03/2022] Open
Abstract
Introduction: Smoking, which is a major modifiable risk factor for coronary artery diseases, affects cardiovascular system with different mechanisms. We designed this study to investigate the association of smoking with location of ST-segment elevation myocardial infarction (STEMI), and short-term outcomes during hospitalization. Methods: In 1017 consecutive patients with anterior/inferior STEMI, comprehensive demographic, biochemical data, as well as clinical complications and mortality rate, were recorded. Patients were allocated into two groups based on smoking status and compared regarding the location of myocardial infarction, the emergence of clinical complications and in-hospital mortality in univariate and multivariate logistic regression analysis. Results: Among 1017 patients, 300 patients (29.5%) were smoker and 717 patients (70.5 %) were non-smoker. Smokers were significantly younger and had lower prevalence of diabetes, hyperlipidemia and hypertension. Inferior myocardial infarction was considerably more common in smokers than in non-smokers (45.7% vs. 36%, P = 0.001). Heart failure was developed more commonly in non-smokers (33.9% vs. 20%, P = 0.001). In-hospital mortality was significantly lower in smokers (6.7% vs. 17.3%, P = 0.001). After adjustment for confounding variables, smoking was independently associated with inferior myocardial infarction and lower heart failure [odds ratio: 1.44 (1.06-1.96), P = 0.01 and odds ratio: 0.61 (0.40-0.92), P = 0.02, respectively]. However, in-hospital mortality was not associated with smoking after adjustment for other factors [odds ratio: 0.69 (0.36-1.31), P = 0.2]. Conclusion: Smoking is independently associated with inferior myocardial infarction. Although smokers had lower incidence of heart failure, in-hospital mortality was not different after adjustment for other factors.
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Affiliation(s)
| | | | | | - Babak Nasiri
- Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Bahrami S, Norouzi M. A numerical study on hemodynamics in the left coronary bifurcation with normal and hypertension conditions. Biomech Model Mechanobiol 2018; 17:1785-1796. [DOI: 10.1007/s10237-018-1056-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 07/12/2018] [Indexed: 12/29/2022]
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10
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Nejad AA, Talebi Z, Cheraghali D, Shahbani-Zahiri A, Norouzi M. Pulsatile flow of non-Newtonian blood fluid inside stenosed arteries: Investigating the effects of viscoelastic and elastic walls, arteriosclerosis, and polycythemia diseases. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2018; 154:109-122. [PMID: 29249336 DOI: 10.1016/j.cmpb.2017.11.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 10/27/2017] [Accepted: 11/14/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND AND OBJECTIVE In this study, the interaction of pulsatile blood flow with the viscoelastic walls of the axisymmetric artery is numerically investigated for different severities of stenosis. The geometry of artery is modeled by an axisymmetric cylindrical tube with a symmetric stenosis in a two-dimensional case. The effects of stenosis severity on the axial velocity profile, pressure distribution, streamlines, wall shear stress, and wall radial displacement for the viscoelastic artery are also compared to the elastics artery. Furthermore, the effects of atherosclerosis and polycythemia diseases on the hemodynamics and the mechanical behavior of arterial walls are investigated. METHODS The pulsatile flow of non-Newtonian blood is simulated inside the viscoelastic artery using the COMSOL Multiphysics software (version 5) and by employing the fluid-structure interaction (FSI) method and the arbitrary Lagrangian-Eulerian (ALE) method. Moreover, finite element method (FEM) is used to solve the governing equations on the unstructured grids. For modeling the non-Newtonian blood fluid and the viscoelastic arterial wall, the modified Casson model, and generalized Maxwell model are used, respectively. RESULTS According to the results, with stenosis severity increasing from 25% to 75% at the time of maximum volumetric flow rate, the maximum value of axial velocity and its gradient increase 7.9 and 19.6 times, and the maximum wall shear stress of viscoelastic wall increases 24.2 times in the constriction zone. With the progression of the atherosclerosis disease (fivefold growth of arterial elastic modulus), the wall radial displacement of viscoelastic arterial walls decreases nearly 40%. CONCLUSIONS In this study, axial velocity profile, pressure distribution, streamlines, wall radial displacement, and wall shear stress were examined for different percentages of stenosis (25%, 50%, and 75%). The atherosclerosis disease was investigated by the fivefold growth of viscoelastic arterial elastic modulus and polycythemia disease was examined by the 21-fold increase in the yield stress of the blood fluid. Furthermore, the comparison of results between the elastic and viscoelastic arterial walls shows that the wall radial displacement for viscoelastic artery is lower than that for the elastic artery as much as 21.7% for the severe stenosis of 75%.
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Affiliation(s)
- A Abbas Nejad
- Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Z Talebi
- Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - D Cheraghali
- Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
| | - A Shahbani-Zahiri
- Department of Mechanical Engineering, University of Birjand, Birjand, Iran
| | - M Norouzi
- Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran.
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Hanafizadeh P, Mirkhani N, Davoudi MR, Masouminia M, Sadeghy K. Non-Newtonian Blood Flow Simulation of Diastolic Phase in Bileaflet Mechanical Heart Valve Implanted in a Realistic Aortic Root Containing Coronary Arteries. Artif Organs 2017; 40:E179-E191. [PMID: 27739601 DOI: 10.1111/aor.12787] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 04/22/2016] [Accepted: 05/17/2016] [Indexed: 11/28/2022]
Abstract
Coronary arteries, which are branched from the sinuses, have tangible effects on the hemodynamic performance of the bileaflet mechanical heart valve (BMHV), especially in the diastolic phase. To better understand this issue, a computer model of ascending aorta including realistic sinus shapes and coronary arteries has been generated in this study in order to investigate the BMHV performance during diastole. Three-dimensional transient numerical analysis is conducted to simulate the diastolic blood flow through the hinges and in coronary arteries under the assumption of non-Newtonian behavior. Results indicate that as blood flows to the coronary arteries mainly during diastole, leakage flow from the hinge and other gaps will change considering the influence of coronary arteries. In addition, BMHV in the case of aortic replacement will increase blood flow rate into the coronary arteries about 100% as the mechanical valve resistance is higher than a native heart valve. Also, it will change the wall shear stress (WSS) distribution and increase coronary artery disease (CAD) potential. It is found out that although less leakage flow reduces the velocity magnitudes through the gaps, the shear stress acting on blood elements with non-Newtonian assumption will be detrimental in the hinge corner at the ventricular side. High WSS of 1800 Pa is observed at beginning of diastole at this region.
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Affiliation(s)
- Pedram Hanafizadeh
- Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
| | - Nima Mirkhani
- Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | | | - Mahtab Masouminia
- Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Keyvan Sadeghy
- Center of Excellence in Design and Optimization of Energy Systems, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
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12
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Identification of DVT diseases using numerical simulations. Med Biol Eng Comput 2016; 54:1591-609. [DOI: 10.1007/s11517-015-1446-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/18/2015] [Indexed: 10/22/2022]
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