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Qi W, Ooi A, Grayden DB, Opie NL, John SE. Haemodynamics of stent-mounted neural interfaces in tapered and deformed blood vessels. Sci Rep 2024; 14:7212. [PMID: 38532013 DOI: 10.1038/s41598-024-57460-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 03/18/2024] [Indexed: 03/28/2024] Open
Abstract
The endovascular neural interface provides an appealing minimally invasive alternative to invasive brain electrodes for recording and stimulation. However, stents placed in blood vessels have long been known to affect blood flow (haemodynamics) and lead to neointimal growth within the blood vessel. Both the stent elements (struts and electrodes) and blood vessel wall geometries can affect the mechanical environment on the blood vessel wall, which could lead to unfavourable vascular remodelling after stent placement. With increasing applications of stents and stent-like neural interfaces in venous blood vessels in the brain, it is necessary to understand how stents affect blood flow and tissue growth in veins. We explored the haemodynamics of a stent-mounted neural interface in a blood vessel model. Results indicated that blood vessel deformation and tapering caused a substantial change to the lumen geometry and the haemodynamics. The neointimal proliferation was evaluated in sheep implanted with an endovascular neural interface. Analysis showed a negative correlation with the mean Wall Shear Stress pattern. The results presented here indicate that the optimal stent oversizing ratio must be considered to minimise the haemodynamic impact of stenting.
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Affiliation(s)
- Weijie Qi
- Department of Biomedical Engineering, The University of Melbourne, Parkville, Australia.
| | - Andrew Ooi
- Department of Mechanical Engineering, The University of Melbourne, Parkville, Australia
| | - David B Grayden
- Department of Biomedical Engineering, The University of Melbourne, Parkville, Australia
- Graeme Clark Institute, The University of Melbourne, Parkville, Australia
| | - Nicholas L Opie
- Vascular Bionics Laboratory, Department of Medicine, The University of Melbourne, Melbourne, VIC, Australia
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
| | - Sam E John
- Department of Biomedical Engineering, The University of Melbourne, Parkville, Australia
- Graeme Clark Institute, The University of Melbourne, Parkville, Australia
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
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2
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Farajtabar M, Larimi MM, Biglarian M, Sabour D, Miansari M. Machine Learning Identification Framework of Hemodynamics of Blood Flow in Patient-Specific Coronary Arteries with Abnormality. J Cardiovasc Transl Res 2022:10.1007/s12265-022-10339-5. [DOI: 10.1007/s12265-022-10339-5] [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: 07/21/2022] [Accepted: 11/03/2022] [Indexed: 11/19/2022]
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3
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Qu Z, Wei H, Du T, Qiao A. Computational simulation of stent thrombosis induced by various degrees of stent malapposition. Front Bioeng Biotechnol 2022; 10:1062529. [PMID: 36452211 PMCID: PMC9701824 DOI: 10.3389/fbioe.2022.1062529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 10/31/2022] [Indexed: 07/02/2024] Open
Abstract
Percutaneous coronary intervention with stent implantation is one of the most commonly used approaches to treat coronary artery stenosis. Stent malapposition (SM) can increase the incidence of stent thrombosis, but the quantitative association between SM distance and stent thrombosis is poorly clarified. The objective of this study is to determine the biomechanical reaction mechanisms underlying stent thrombosis induced by SM and to quantify the effect of different SM severity grades on thrombosis. The thrombus simulation was performed in a continuous model based on the diffusion-convection response of blood substance transport. Simulated models included well-apposed stents and malapposed stents with various severities where the detachment distances ranged from 0 to 400 μm. The abnormal shear stress induced by SM was considered a critical contributor affecting stent thrombosis, which was dependent on changing SM distances in the simulation. The results illustrate that the proportion of thrombus volume was 1.88% at a SM distance of 75 μm (mild), 3.46% at 150 μm, and 3.93% at 400 μm (severe), but that a slight drop (3.18%) appeared at the detachment distance of 225 μm (intermediate). The results indicate that when the SM distance was less than 150 μm, the thrombus rose notably as the gap distance increased, whereas the progression of thrombogenicity weakened when it exceeded 150 μm. Therefore, more attention should be paid when SM is present at a gap distance of 150 μm. Moreover, when the SM length of stents are the same, thrombus tends to accumulate downstream towards the distal end of the stent as the SM distance increases.
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Affiliation(s)
| | | | | | - Aike Qiao
- Faculty of Environment and Life, Beijing University of Technology, Beijing, China
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4
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Saleem T, Raju S. An overview of in-stent restenosis in iliofemoral venous stents. J Vasc Surg Venous Lymphat Disord 2021; 10:492-503.e2. [PMID: 34774813 DOI: 10.1016/j.jvsv.2021.10.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/13/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND Although endovenous stents have been associated with overall low morbidity, they can require reinterventions to correct stent malfunction due to in-stent restenosis (ISR). ISR has often occurred iliofemoral venous stents but has not been well described. It has been reported to develop in >70% of patients who have undergone iliofemoral venous stenting. We sought to provide an overview of ISR in iliofemoral venous stents, including the pathologic, diagnostic, and management considerations and the identification of several areas of potential research in the future. METHODS A search of reported English-language studies was performed in PubMed and the Cochrane Library. "In-stent restenosis," "vein," "venous," "iliac," and "iliofemoral" were used as keywords. The pertinent reports included in the present review had addressed the pathology, diagnosis, and current management options for ISR. RESULTS ISR refers to the narrowing of the luminal caliber of the stent owing to the development of stenosis inside the stent itself. ISR should be differentiated from stent compression. Two main types of ISR have been described: soft and hard lesions. These lesions respond differently to angioplasty. Stent inflow and shear stress are important factors in the development of ISR. The treatment options available at present include balloon angioplasty (hyperdilation or isodilation), laser ablation, atherectomy, and Z-stent placement. CONCLUSIONS Reintervention for ISR should be determined by the presence of residual or recurrent symptoms and not simply by a numeric value obtained from an imaging study. Overall stent occlusion due to ISR is rare, and no role exists for prophylactic angioplasty to treat asymptomatic ISR. The current treatment options for ISR are mostly durable and effective. However, more research is needed on methods to prevent the development of ISR. The role of antiplatelet and anticoagulant agents in the prevention of ISR requires further investigation, with particular attention to unique subset of patients (after thrombosis vs nonthrombotic iliac vein lesions). For high-risk, post-thrombotic patients, anticoagulation can be considered to prevent ISR. The role of triple therapy (anticoagulation and dual antiplatelet therapy) in the prevention of ISR remains unclear.
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Affiliation(s)
- Taimur Saleem
- The RANE Center for Venous and Lymphatic Diseases, Jackson, Miss.
| | - Seshadri Raju
- The RANE Center for Venous and Lymphatic Diseases, Jackson, Miss
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5
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Gamage PT, Dong P, Lee J, Gharaibeh Y, Zimin VN, Dallan LAP, Bezerra HG, Wilson DL, Gu L. Hemodynamic alternations following stent deployment and post-dilation in a heavily calcified coronary artery: In silico and ex-vivo approaches. Comput Biol Med 2021; 139:104962. [PMID: 34715552 DOI: 10.1016/j.compbiomed.2021.104962] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/16/2021] [Accepted: 10/17/2021] [Indexed: 01/16/2023]
Abstract
In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in silico and ex-vivo approaches. Three-dimensional artery models were reconstructed from OCT images. Stent deployment and post-dilation with various inflation pressures were performed through both the finite element method (FEM) and ex vivo experiments. Results from FEM agreed very well with the ex-vivo measurements, interms of lumen areas, stent underexpansion, and strut malapposition. In addition, computational fluid dynamics (CFD) simulations were performed to delineate the hemodynamic alterations after stent deployment and post-dilations. A pressure time history at the inlet and a lumped parameter model (LPM) at the outlet were adopted to mimic the aortic pressure and the distal arterial tree, respectively. The pressure drop across the lesion, pertaining to the clinical measure of instantaneous wave-free flow ratio (iFR), was investigated. Results have shown that post-dilations are necessary for the lumen gain as well as the hemodynamic restoration towards hemostasis. Malapposed struts induced much higher shear rate, flow disturbances and lower time-averaged wall shear stress (TAWSS) around struts. Post-dilations mitigated the strut malapposition, and thus the shear rate. Moreover, stenting induced larger area of low TAWSS (<0.4 Pa) and lager volume of high shear rate (>2000 s-1), indicating higher risks of in-stent restenosis (ISR) and stent thrombosis (ST), respectively. Oscillatory shear index (OSI) and relative residence time (RRT) indicated the wall regions more prone to ISR are located near the malapposed stent struts.
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Affiliation(s)
- Peshala T Gamage
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - Pengfei Dong
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL, 32901, USA.
| | - Juhwan Lee
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Yazan Gharaibeh
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Vladislav N Zimin
- Cardiovascular Imaging Core Laboratory, Harrington Heart & Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, 44106, USA
| | - Luis A P Dallan
- Cardiovascular Imaging Core Laboratory, Harrington Heart & Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, 44106, USA
| | - Hiram G Bezerra
- Interventional Cardiology Center, Heart and Vascular Institute, The University of South Florida, Tampa, FL, 33606, USA
| | - David L Wilson
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Linxia Gu
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL, 32901, USA.
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6
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Wei L, Wang J, Chen Q, Li Z. Impact of stent malapposition on intracoronary flow dynamics: An optical coherence tomography-based patient-specific study. Med Eng Phys 2021; 94:26-32. [PMID: 34303498 DOI: 10.1016/j.medengphy.2021.06.002] [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: 11/13/2020] [Revised: 05/10/2021] [Accepted: 06/04/2021] [Indexed: 10/21/2022]
Abstract
Percutaneous coronary intervention with stent implantation has emerged as a popular approach to treat coronary artery stenosis. Stent malapposition (SM), also referred as incomplete stent apposition, could reduce stent tissue coverage and hence increase the risk of late stent thrombosis. The objective of this study was to investigate the impact of SM on intracoronary flow dynamics by combining optical coherence tomography (OCT) image-based model reconstruction and computational analysis. Firstly, a stenosed coronary artery model was reconstructed from OCT and angiography imaging data of a patient. Two structural analyses were carried out to simulate two types of coronary artery stent implantations: a fully-apposed (FA) case and a SM case. Then, based on the two deformed coronary geometries, two computational fluid dynamics (CFD) analyses were performed to evaluate the differences of hemodynamic metrics between the FA and the SM cases, including wall shear stress (WSS), time-averaged WSS (TWSS), oscillatory shear index (OSI), WSS gradient (WSSG), time-averaged WSSG (TWSSG), and relative residence time (RRT). The results indicated that maximum flow velocity was higher in the SM case than that of the FA case, due to the incomplete expansion of the stent and artery. Moreover, the SM case had a lower percentage of areas of adverse WSS (< 0.5 Pa) and RRT (> 10/Pa) but a higher percentage of areas of adverse OSI (> 0.1) and WSSG (> 5000 Pa/m). Specifically, the differences of OSI, WSSG, and RRT between the two cases were relatively small. It was suggested that SM might not be responsible for negative hemodynamic metrics which would further result in stent thrombosis on the basis of the present specific model.
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Affiliation(s)
- Lingling Wei
- Biomechanics Laboratory, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, PR China
| | - Jiaqiu Wang
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane QLD 4001, Australia
| | - Qiang Chen
- Biomechanics Laboratory, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, PR China.
| | - Zhiyong Li
- Biomechanics Laboratory, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, PR China; School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane QLD 4001, Australia.
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7
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Impact of Malapposed and Overlapping Stents on Hemodynamics: A 2D Parametric Computational Fluid Dynamics Study. MATHEMATICS 2021. [DOI: 10.3390/math9080795] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Despite significant progress, malapposed or overlapped stents are a complication that affects daily percutaneous coronary intervention (PCI) procedures. These malapposed stents affect blood flow and create a micro re-circulatory environment. These disturbances are often associated with a change in Wall Shear Stress (WSS), Time-averaged WSS (TAWSS), relative residence time (RRT) and oscillatory character of WSS and disrupt the delicate balance of vascular biology, providing a possible source of thrombosis and restenosis. In this study, 2D axisymmetric parametric computational fluid dynamics (CFD) simulations were performed to systematically analyze the hemodynamic effects of malapposition and stent overlap for two types of stents (drug-eluting stent and a bioresorbable stent). The results of the modeling are mainly analyzed using streamlines, TAWSS, oscillatory shear index (OSI) and RRT. The risks of restenosis and thrombus are evaluated according to commonly accepted thresholds for TAWSS and OSI. The small malapposition distances (MD) cause both low TAWSS and high OSI, which are potential adverse outcomes. The region of low OSI decrease with MD. Overlap configurations produce areas with low WSS and high OSI. The affected lengths are relatively insensitive to the overlap distance. The effects of strut size are even more sensitive and adverse for overlap configurations compared to a well-applied stent.
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8
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Lan L, Liu H, Ip V, Soo Y, Abrigo J, Fan F, Ma SH, Ma K, Ip B, Liu J, Fan Y, Zeng J, Mok V, Wong L, Liebeskind D, Leung T, Leng X. Regional High Wall Shear Stress Associated With Stenosis Regression in Symptomatic Intracranial Atherosclerotic Disease. Stroke 2020; 51:3064-3073. [PMID: 32883193 DOI: 10.1161/strokeaha.120.030615] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background and Purpose:
Understanding the mechanisms underlying progression/regression of symptomatic intracranial atherosclerotic stenosis (sICAS) will inform secondary prevention of the patients. Focal wall shear stress (WSS) may play an important role, which, however, had seldom been investigated.
Methods:
Patients with acute ischemic stroke or transient ischemic attack (TIA) attributed to 50% to 99% intracranial atherosclerotic stenosis were recruited. All patients underwent cerebral computed tomography angiography at baseline, and a computational fluid dynamics model was built based on computed tomography angiography to simulate blood flow and quantify WSS in the vicinity of the sICAS lesion. All patients received optimal medical treatment and a second computed tomography angiography at 1 year. The change in the luminal stenosis from baseline to 1 year in sICAS was defined as progression (increased >10%), quiescence (±10%), or regression (decreased >10%). Associations between baseline WSS metrics and sICAS regression were analyzed.
Results:
Among 39 patients (median age 62 years; 27 males), sICAS luminal stenosis progressed, remained quiescent and regressed in 6 (15.4%), 15 (38.5%), and 18 (46.2%) cases, respectively. A higher maximum WSS and larger high-WSS area, throughout the sICAS lesion or obtained separately in the proximal and distal parts of the lesion, were independently associated with regression of luminal stenosis in sICAS over 1 year.
Conclusions:
A majority of sICAS lesions regress or stay quiescent in the luminal stenosis over 1 year after stroke under optimal medical treatment, when higher focal WSS may facilitate stenosis regression. Further studies of the effects of hemodynamics including WSS in altering plaque vulnerability and stroke risks are needed.
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Affiliation(s)
- Linfang Lan
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University (L.L., Y.F., J.Z.)
- Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou, China (L.L., Y.F., J.Z.)
| | - Haipeng Liu
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
- Department of Imaging and Interventional Radiology (H.L., J.A.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
- Research Centre of Intelligent Healthcare, Faculty of Health and Life Science, Coventry University, United Kingdom (H.L.)
| | - Vincent Ip
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Yannie Soo
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Jill Abrigo
- Department of Imaging and Interventional Radiology (H.L., J.A.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Florence Fan
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Sze Ho Ma
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Karen Ma
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Bonaventure Ip
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Jia Liu
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, China (J.L.)
| | - Yuhua Fan
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University (L.L., Y.F., J.Z.)
- Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou, China (L.L., Y.F., J.Z.)
| | - Jinsheng Zeng
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University (L.L., Y.F., J.Z.)
- Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangzhou, China (L.L., Y.F., J.Z.)
| | - Vincent Mok
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - Lawrence Wong
- Department of Medicine and Therapeutics (L.L., H.L., V.I., Y.S., F.F., S.H.M., K.M., B.I., V.M., L.W., T.L., X.L.), The Chinese University of Hong Kong, Prince of Wales Hospital, China
| | - David Liebeskind
- Department of Neurology, Neurovascular Imaging Research Core and UCLA Stroke Center, University of California Los Angeles (D.L.)
| | | | - Xinyi Leng
- Shenzhen Research Institute, The Chinese University of Hong Kong, China (X.L.)
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9
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Biglarian M, Larimi MM, Afrouzi HH, Moshfegh A, Toghraie D, Javadzadegan A, Rostami S. Computational investigation of stenosis in curvature of coronary artery within both dynamic and static models. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 185:105170. [PMID: 31710988 DOI: 10.1016/j.cmpb.2019.105170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/27/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE Blood flow variation during cardiac cycle is the main mechanism of atherosclerotic development which is dependent on. METHODS The present work mainly tends to investigate stenosis effect in dynamic curvature of coronary artery. This paper presents numerical investigations on wall shear stress profiles in three-dimensional pulsatile flow through curved stenotic coronary arteries for both static and dynamic model. In order to do so, three-dimensional models related to the curved arteries with two degrees of stenosis (30% and 50%). RESULTS Lower amount of wall shear stress is found near the inner wall of artery distal to the plaque region (stenosis) and in both percentages of stenosis the maximum wall shear stress will accrue in the middle of the stenosis; however it is much more in the higher rate of stenosis. CONCLUSIONS A chaotic wall shear stress region is also observed downstream of stenosis in the severe stenosis case. Finally it concluded that the arterial wall motion affects the wall shear stress and the plaque formation site.
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Affiliation(s)
- Mohit Biglarian
- Faculty of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Morsal Momeni Larimi
- Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | | | - Abouzar Moshfegh
- ANZAC Research Institute, the University of Sydney, Sydney NSW 2139, Australia
| | - Davood Toghraie
- Department of Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Khomeinishahr, Iran
| | - Ashkan Javadzadegan
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney NSW 2109, Australia
| | - Sara Rostami
- Laboratory of Magnetism and Magnetic Materials, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam; Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
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10
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Jiang B, Thondapu V, Poon E, Barlis P, Ooi A. Numerical study of incomplete stent apposition caused by deploying undersized stent in arteries with elliptical cross-sections. J Biomech Eng 2019; 141:2725823. [PMID: 30778567 DOI: 10.1115/1.4042899] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Indexed: 12/26/2022]
Abstract
Incomplete stent apposition (ISA) is one of the causes leading to post-stent complications, which can be found when an undersized or under-expanded stent is deployed at lesions. Previous research efforts have focused on ISA in idealized coronary arterial geometry with circular cross-sections. However, arterial cross-section eccentricity plays an important role in both location and severity of ISA. Computational fluid dynamics (CFD) simulations are carried out to systematically study the effects of ISA in arteries with elliptical cross-sections, as such stents are partially embedded on the minor axis sides of the ellipse and malapposed elsewhere. Overall, ISA leads to high time-averaged WSS (TAWSS) at the proximal end of the stent and low TAWSS at the ISA transition region and the distal end. Shear rate depends on both malapposition distance and blood stream locations, which is found to be significantly higher at the inner stent surface than the outer surface. The proximal high shear rate signifies increasing possibility in platelet activation, when coupled with low TAWSS at the transition and distal region which may indicate a nidus for in-stent thrombosis.
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Affiliation(s)
- Bo Jiang
- Department of Mechanical Engineering, The University of Melbourne, Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia
| | - Vikas Thondapu
- Department of Mechanical Engineering, The University of Melbourne, Department of Medicine, Faculty of Medicine, Dentistry & Health Sciences, The University of Melbourne, Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia
| | - Eric Poon
- Department of Mechanical Engineering, The University of Melbourne, Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia
| | - Peter Barlis
- Department of Medicine, Faculty of Medicine, Dentistry & Health Sciences, The University of Melbourne, Department of Medicine, Faculty of Medicine, Dentistry & Health Sciences, The University of Melbourne, Victoria 3010, Australia
| | - Andrew Ooi
- Department of Mechanical Engineering, The University of Melbourne, Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia
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11
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Abdel-Karim ARR, Uretsky BF. The importance of malapposition in angiographically optimized stenting in contemporaneous interventions. Expert Rev Cardiovasc Ther 2018; 16:599-605. [DOI: 10.1080/14779072.2018.1493377] [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: 10/28/2022]
Affiliation(s)
| | - Barry F. Uretsky
- Division of Cardiology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
- Division of Cardiology, Central Arkansas Veterans Healthcare System and the University of Arkansas for Medical Sciences, Little Rock, AR, USA
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12
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Poon EKW, Thondapu V, Hayat U, Barlis P, Yap CY, Kuo PH, Wang Q, Ma J, Zhu SJ, Moore S, Ooi ASH. Elevated Blood Viscosity and Microrecirculation Resulting From Coronary Stent Malapposition. J Biomech Eng 2018; 140:2673009. [DOI: 10.1115/1.4039306] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Indexed: 01/09/2023]
Abstract
One particular complexity of coronary artery is the natural tapering of the vessel with proximal segments having larger caliber and distal tapering as the vessel get smaller. The natural tapering of a coronary artery often leads to proximal incomplete stent apposition (ISA). ISA alters coronary hemodynamics and creates pathological path to develop complications such as in-stent restenosis, and more worryingly, stent thrombosis (ST). By employing state-of-the-art computer-aided design software, generic stent hoops were virtually deployed in an idealized tapered coronary artery with decreasing malapposition distance. Pulsatile blood flow simulations were carried out using computational fluid dynamics (CFD) on these computer-aided design models. CFD results reveal unprecedented details in both spatial and temporal development of microrecirculation environments throughout the cardiac cycle (CC). Arterial tapering also introduces secondary microrecirculation. These primary and secondary microrecirculations provoke significant fluctuations in arterial wall shear stress (WSS). There has been a direct correlation with changes in WSS and the development of atherosclerosis. Further, the presence of these microrecirculations influence strongly on the local levels of blood viscosity in the vicinity of the malapposed stent struts. The observation of secondary microrecirculations and changes in blood rheology is believed to complement the wall (-based) shear stress, perhaps providing additional physical explanations for tissue accumulation near ISA detected from high resolution optical coherence tomography (OCT).
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Affiliation(s)
- Eric K. W. Poon
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Vikas Thondapu
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia
- Faculty of Medicine, Dentistry, and Health Sciences, Department of Medicine, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Umair Hayat
- Faculty of Medicine, Dentistry and Health Sciences, Department of Medicine, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Peter Barlis
- Department of Medicine, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Chooi Yin Yap
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Po-Hung Kuo
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Qisen Wang
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Jiawei Ma
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Shuang J. Zhu
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
| | - Stephen Moore
- IBM Research Australia, Carlton 3053, Victoria, Australia e-mail:
| | - Andrew S. H. Ooi
- Department of Mechanical Engineering, Melbourne School of Engineering, The University of Melbourne, Melbourne 3010, Victoria, Australia e-mail:
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