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Computational Study of Hemodynamic Field of an Occluded Artery Model with Anastomosis. Bioengineering (Basel) 2023; 10:bioengineering10020146. [PMID: 36829640 PMCID: PMC9952429 DOI: 10.3390/bioengineering10020146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 01/24/2023] Open
Abstract
In this research work, the hemodynamic field of an occluded artery with anastomosis by means of computational simulation has been studied. The main objective of the current study is the investigation of 3D flow field phenomena in the by-pass region and the effect of the bypass graft to stenosis volume flow ratio on their formation. The anastomosis type was end-to-side with a 45° angle, while stenosis imposed a 75% area blockage of the aorta vessel and the total volume flow was 220 lt/h. The computational study of the flow field was utilized via a laminar flow model and three turbulence models (k-ε RNG, standard k-ω, and k-ω SST). Numerical results were compared qualitatively with experimental visualizations carried out under four different flow conditions, varying according to the flow ratio between the stenosis and the anastomotic graft. Comparison between computational results and experimental visualization findings exhibited a good agreement. Results showed that SST k-ω turbulence models reproduce better visually obtained flow patterns. Furthermore, cross-sectional velocity distributions demonstrated two distinct flow patterns down the bypass graft, depending on the flow ratio. Low values of flow ratio are characterized by fluid rolling up, whereas for high values fluid volume twisting was observed. Finally, areas with low wall shear stresses were mapped, as these are more prone to postoperative degradation of the bypass graft due to the development of subendothelial hyperplasia.
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2
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Jodko D, Jeckowski M, Tyfa Z. Fluid structure interaction versus rigid-wall approach in the study of the symptomatic stenosed carotid artery: Importance of wall compliance and resilience of loose connective tissue. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2022; 38:e3630. [PMID: 35593678 PMCID: PMC9542585 DOI: 10.1002/cnm.3630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/11/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
The purpose of this paper is to demonstrate the importance of a compliant wall approach in modeling of non-Newtonian and non-physiological blood flows. A case study of a stenosed and symptomatic carotid bifurcation was considered to show the influence of the wall-resilience assumption on the flow parameters obtained with numerical simulations. Patient-specific data concerning the geometry and flow conditions were collected and used to carry out two-way coupled fluid structure interaction simulations of the pulsatile blood flow through carotid artery. The wall compliance was considered separately as related to the wall-elasticity and as associated with the reaction of the loose connective tissue surrounding the carotid bifurcation. The obtained hemodynamic parameters were compared to those which were found in rigid-wall simulations. The difference between the results obtained for rigid-wall and compliant-wall approaches for the peak-systolic area-averaged wall shear stress achieved 35%, whereas the difference between the time-averaged local vorticity and shear strain reached, respectively, 42% and 43%. The influence of the highly resilient wall on the monitored hemodynamic parameters was significant even if time-averaged values are compared, which suggests that these metrics are considerably overestimated if the wall compliance is not considered. Moreover, the findings show that the mechanical response of the loose connective tissue cannot be neglected in blood flow simulations. Additionally, this study indicates that stiffening of the arterial wall due to atherosclerosis significantly rises hemodynamic parameters. This explains the therapeutic benefits of surgical removal of plaque lesions formed in the carotid bifurcation (endarterectomy).
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Affiliation(s)
- Daniel Jodko
- Institute of TurbomachineryLodz University of TechnologyLodzPoland
| | - Mateusz Jeckowski
- Department of Experimental SurgeryMedical University of LodzLodzPoland
| | - Zbigniew Tyfa
- Institute of TurbomachineryLodz University of TechnologyLodzPoland
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3
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De Nisco G, Chiastra C, Hartman EMJ, Hoogendoorn A, Daemen J, Calò K, Gallo D, Morbiducci U, Wentzel JJ. Comparison of Swine and Human Computational Hemodynamics Models for the Study of Coronary Atherosclerosis. Front Bioeng Biotechnol 2021; 9:731924. [PMID: 34409022 PMCID: PMC8365882 DOI: 10.3389/fbioe.2021.731924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 07/22/2021] [Indexed: 12/14/2022] Open
Abstract
Coronary atherosclerosis is a leading cause of illness and death in Western World and its mechanisms are still non completely understood. Several animal models have been used to 1) study coronary atherosclerosis natural history and 2) propose predictive tools for this disease, that is asymptomatic for a long time, aiming for a direct translation of their findings to human coronary arteries. Among them, swine models are largely used due to the observed anatomical and pathophysiological similarities to humans. However, a direct comparison between swine and human models in terms of coronary hemodynamics, known to influence atherosclerotic onset/development, is still lacking. In this context, we performed a detailed comparative analysis between swine- and human-specific computational hemodynamic models of coronary arteries. The analysis involved several near-wall and intravascular flow descriptors, previously emerged as markers of coronary atherosclerosis initiation/progression, as well as anatomical features. To do that, non-culprit coronary arteries (18 right–RCA, 18 left anterior descending–LAD, 13 left circumflex–LCX coronary artery) from patients presenting with acute coronary syndrome were imaged by intravascular ultrasound and coronary computed tomography angiography. Similarly, the three main coronary arteries of ten adult mini-pigs were also imaged (10 RCA, 10 LAD, 10 LCX). The geometries of the imaged coronary arteries were reconstructed (49 human, 30 swine), and computational fluid dynamic simulations were performed by imposing individualized boundary conditions. Overall, no relevant differences in 1) wall shear stress-based quantities, 2) intravascular hemodynamics (in terms of helical flow features), and 3) anatomical features emerged between human- and swine-specific models. The findings of this study strongly support the use of swine-specific computational models to study and characterize the hemodynamic features linked to coronary atherosclerosis, sustaining the reliability of their translation to human vascular disease.
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Affiliation(s)
- Giuseppe De Nisco
- PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Claudio Chiastra
- PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Eline M J Hartman
- Department of Cardiology, Biomedical Engineering, Erasmus MC, Rotterdam, Netherlands
| | - Ayla Hoogendoorn
- Department of Cardiology, Biomedical Engineering, Erasmus MC, Rotterdam, Netherlands
| | - Joost Daemen
- Department of Cardiology, Biomedical Engineering, Erasmus MC, Rotterdam, Netherlands
| | - Karol Calò
- PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Diego Gallo
- PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Umberto Morbiducci
- PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Jolanda J Wentzel
- Department of Cardiology, Biomedical Engineering, Erasmus MC, Rotterdam, Netherlands
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Abstract
Atherosclerosis is one of the main causes of cardiovascular events, namely, myocardium infarction and cerebral stroke, responsible for a great number of deaths every year worldwide. This pathology is caused by the progressive accumulation of low-density lipoproteins, cholesterol, and other substances on the arterial wall, narrowing its lumen. To date, many hemodynamic studies have been conducted experimentally and/or numerically; however, this disease is not yet fully understood. For this reason, the research of this pathology is still ongoing, mainly, resorting to computational methods. These have been increasingly used in biomedical research of atherosclerosis because of their high-performance hardware and software. Taking into account the attempts that have been made in computational techniques to simulate realistic conditions of blood flow in both diseased and healthy arteries, the present review aims to give an overview of the most recent numerical studies focused on coronary arteries, by addressing the blood viscosity models, and applied physiological flow conditions. In general, regardless of the boundary conditions, numerical studies have been contributed to a better understanding of the development of this disease, its diagnosis, and its treatment.
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5
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Blood flow simulations in patient-specific geometries of the carotid artery: A systematic review. J Biomech 2020; 111:110019. [PMID: 32905972 DOI: 10.1016/j.jbiomech.2020.110019] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/07/2020] [Accepted: 08/26/2020] [Indexed: 12/21/2022]
Abstract
Computational Fluid Dynamics (CFD) and Fluid-Structure Interaction (FSI) are currently widely applied in the study of blood flow parameters and their alterations under pathological conditions, which are important indicators for diagnosis of atherosclerosis. In this manuscript, a systematic review of the published literature was conducted, according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, on the simulation studies of blood flow in patient-specific geometries of the carotid artery bifurcation. Scopus, PubMed and ScienceDirect databases were used in the literature search, which was completed on the 3rd of August 2020. Forty-nine articles were included after the selection process and were organized in two distinct categories: the CFD studies (36/49 articles), which comprise only the fluid analysis and the FSI studies (13/49 articles), which includes both fluid and Fluid-Structure domain in the analysis. The data of the research works was structured in different categories (Geometry, Viscosity models, Type of Flow, Boundary Conditions, Flow Parameters, Type of Solver and Validation). The aim of this systematic review is to demonstrate the methodology in the modelling, simulation and analysis of carotid blood flow and also identify potential gaps and challenges in this research field.
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Pandey R, Kumar M, Majdoubi J, Rahimi-Gorji M, Srivastav VK. A review study on blood in human coronary artery: Numerical approach. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 187:105243. [PMID: 31805457 DOI: 10.1016/j.cmpb.2019.105243] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/23/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Computational fluid dynamics (CFD) study of blood flow in human coronary artery is one of the emerging fields of Biomed- ical engineering. In present review paper, Finite Volume Method with governing equations and boundary conditions are briefly discussed for different coronary models. Many researchers have come up with astonishing results related to the various factors (blood viscosity, rate of blood flow, shear stress on the arterial wall, Reynolds number, etc.) affecting the hemodynamic of blood in the right/left coronary artery. The aim of this paper is to present an overview of all those work done by the researchers to justify their work related to factors which hampers proper functioning of heart and lead to Coronary Artery Disease (CAD). Governing equations like Navier-stokes equations, continuity equations etc. are widely used and are solved using CFD solver to get a clearer view of coronary artery blockage. Different boundary conditions and blood properties published in the last ten years are summarized in the tabulated form. This table will help new researchers to work on this area.
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Affiliation(s)
- Rupali Pandey
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, India.
| | - Manoj Kumar
- Department of Mathematics, Motilal Nehru National Institute of Technology Allahabad, India.
| | - Jihen Majdoubi
- Department of Computer Science, College of Science and Humanities at Alghat, Majmaah University, Al-Majmaah 11952, Saudi Arabia.
| | - Mohammad Rahimi-Gorji
- Experimental Surgery Lab, Faculty of Medicine and Health Science, Ghent University, 9000 Gent, Belgium.
| | - Vivek Kumar Srivastav
- Department of Mathematics & Computing, Motihari college of Engineering, Bihar, India.
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Vascular, cardiac and renal target organ damage associated to arterial hypertension: which noninvasive tools for detection? J Hum Hypertens 2020; 34:420-431. [DOI: 10.1038/s41371-020-0307-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 01/04/2020] [Accepted: 01/27/2020] [Indexed: 01/16/2023]
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8
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Microfluidic models of physiological or pathological flow shear stress for cell biology, disease modeling and drug development. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.06.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Karlas A, Fasoula NA, Paul-Yuan K, Reber J, Kallmayer M, Bozhko D, Seeger M, Eckstein HH, Wildgruber M, Ntziachristos V. Cardiovascular optoacoustics: From mice to men - A review. PHOTOACOUSTICS 2019; 14:19-30. [PMID: 31024796 PMCID: PMC6476795 DOI: 10.1016/j.pacs.2019.03.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 03/18/2019] [Indexed: 05/04/2023]
Abstract
Imaging has become an indispensable tool in the research and clinical management of cardiovascular disease (CVD). An array of imaging technologies is considered for CVD diagnostics and therapeutic assessment, ranging from ultrasonography, X-ray computed tomography and magnetic resonance imaging to nuclear and optical imaging methods. Each method has different operational characteristics and assesses different aspects of CVD pathophysiology; nevertheless, more information is desirable for achieving a comprehensive view of the disease. Optoacoustic (photoacoustic) imaging is an emerging modality promising to offer novel information on CVD parameters by allowing high-resolution imaging of optical contrast several centimeters deep inside tissue. Implemented with illumination at several wavelengths, multi-spectral optoacoustic tomography (MSOT) in particular, is sensitive to oxygenated and deoxygenated hemoglobin, water and lipids allowing imaging of the vasculature, tissue oxygen saturation and metabolic or inflammatory parameters. Progress with fast-tuning lasers, parallel detection and advanced image reconstruction and data-processing algorithms have recently transformed optoacoustics from a laboratory tool to a promising modality for small animal and clinical imaging. We review progress with optoacoustic CVD imaging, highlight the research and diagnostic potential and current applications and discuss the advantages, limitations and possibilities for integration into clinical routine.
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Affiliation(s)
- Angelos Karlas
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Clinic for Vascular and Endovascular Surgery, University Hospital rechts der Isar, Munich, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
| | - Nikolina-Alexia Fasoula
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Korbinian Paul-Yuan
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Josefine Reber
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Michael Kallmayer
- Clinic for Vascular and Endovascular Surgery, University Hospital rechts der Isar, Munich, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
| | - Dmitry Bozhko
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Markus Seeger
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Hans-Henning Eckstein
- Clinic for Vascular and Endovascular Surgery, University Hospital rechts der Isar, Munich, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
| | - Moritz Wildgruber
- Institute for Diagnostic and Interventional Radiology, University Hospital rechts der Isar, Munich, Germany
- Institute for Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Vasilis Ntziachristos
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
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Sventzouri S, Nanas I, Vakrou S, Kapelios C, Sousonis V, Sfakianaki T, Papalois A, Manolis AS, Nanas JN, Malliaras K. Pharmacologic inhibition of the mitochondrial Na +/Ca 2+ exchanger protects against ventricular arrhythmias in a porcine model of ischemia-reperfusion. Hellenic J Cardiol 2018; 59:217-222. [PMID: 29292245 DOI: 10.1016/j.hjc.2017.12.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 12/03/2017] [Accepted: 12/22/2017] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The mitochondrial Na+/Ca2+ exchanger (mNCX) has been implicated in the pathogenesis of arrhythmogenicity and myocardial reperfusion injury, rendering its inhibition a potential therapeutic strategy. We examined the effects of CGP-37157, a selective mNCX inhibitor, on arrhythmogenesis, infarct size (IS), and no reflow area (NRA) in a porcine model of ischemia-reperfusion. METHODS Forty pigs underwent myocardial ischemia for 60 minutes, followed by 2 hours of reperfusion. Animals were randomized to receive intracoronary infusion of 0.02 mg/kg CGP-37157 or vehicle, either before ischemia (n=17) or before reperfusion (n=17). Animals were monitored for arrhythmias. Myocardial area at risk (AR), IS, and NRA were measured by histopathology. RESULTS AR, NRA, and IS were comparable between groups. Administration of CGP-37157 before ischemia resulted in the following: (a) suppression of ventricular tachyarrhythmias (events/pig: 1.5±1.1 vs 3.5±1.9, p=0.014), (b) easier cardioversion of ventricular tachyarrhythmias (defibrillations required for cardioversion of each episode: 2.6±2.3 vs 6.2±2.1, p=0.006), and (c) decreased maximal depression of the J point (0.75±0.27 mm vs 1.75±0.82 mm, p=0.007), compared to controls. Administration of CGP-37157 before reperfusion expedited ST-segment resolution; complete ST-segment resolution within 30 minutes of reperfusion was observed in 7/8 CGP-37157-treated animals versus 1/9 controls (p=0.003). CONCLUSIONS In a porcine model of myocardial infarction, intracoronary administration of CGP-37157 did not decrease IS or NRA. However, it suppressed ventricular arrhythmias, decreased depression of the J point during ischemia and expedited ST-segment resolution after reperfusion. These findings motivate further investigation of pharmacologic mNCX inhibition as a potential therapeutic strategy to suppress arrhythmias in the injured heart.
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Affiliation(s)
- Stefania Sventzouri
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Ioannis Nanas
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Styliani Vakrou
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Chris Kapelios
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Vasilios Sousonis
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Titika Sfakianaki
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | | | - Antonis S Manolis
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - John N Nanas
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece
| | - Konstantinos Malliaras
- 3rd Department of Cardiology, University of Athens School of Medicine, 11 527, Athens, Greece.
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Xanthopoulou I, Bei I, Bampouri T, Barampoutis N, Moulias A, Davlouros P, Alexopoulos D. Absence of differential effect of ticagrelor versus prasugrel maintenance dose on endothelial function in patients with stable coronary artery disease. Hellenic J Cardiol 2017; 59:338-343. [PMID: 29292242 DOI: 10.1016/j.hjc.2017.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 12/11/2017] [Accepted: 12/19/2017] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Endothelial function may be improved by ticagrelor through adenosine-mediated mechanisms. We aimed to assess the effect of ticagrelor versus prasugrel on endothelial function in patients with stable coronary artery disease (CAD). METHODS In a prospective, randomized, crossover study, 22 stable CAD patients under prasugrel 10 mg once daily maintenance dose (MD) for at least 3 months were randomized to either ticagrelor 90 mg twice daily or prasugrel 10 mg once daily for 15 days with a direct treatment-crossover for another 15 days. Endothelial function was assessed by peripheral arterial tonometry (EndoPAT 2000 system, Itamar Medical, Caesarea, Israel) at Day 0 (randomization), Day 15, and Day 30. Reactive Hyperemia Index (RHI) was calculated by using an automated software, and endothelial dysfunction (ED) was defined as RHI <1.67. RHI at the end of the two treatment periods did not differ between ticagrelor and prasugrel MD treatments. Least squares estimates (95% confidence interval) were 1.78 (1.58-1.99) versus 1.88 (1.67-2.08), with a fixed estimate of -0.099 (95% CI: -0.45 to 0.25) for the difference between them (p = 0.5). ED rate did not differ significantly between ticagrelor and prasugrel (45.5% vs 45.5%, p = 0.6). CONCLUSIONS In CAD patients, we have failed to find evidence of alteration of endothelial function following ticagrelor compared to prasugrel MD treatment, as assessed by peripheral arterial tonometry. CLINICALTRIALS. GOV UNIQUE IDENTIFIER NCT01957540.
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Affiliation(s)
| | - Ilianna Bei
- Department of Cardiology, Patras University Hospital, Rion, Patras, Greece
| | - Theodora Bampouri
- Department of Cardiology, Patras University Hospital, Rion, Patras, Greece
| | | | - Athanasios Moulias
- Department of Cardiology, Patras University Hospital, Rion, Patras, Greece
| | - Periklis Davlouros
- Department of Cardiology, Patras University Hospital, Rion, Patras, Greece
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Migliori S, Chiastra C, Bologna M, Montin E, Dubini G, Aurigemma C, Fedele R, Burzotta F, Mainardi L, Migliavacca F. A framework for computational fluid dynamic analyses of patient-specific stented coronary arteries from optical coherence tomography images. Med Eng Phys 2017; 47:105-116. [PMID: 28711588 DOI: 10.1016/j.medengphy.2017.06.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/09/2017] [Accepted: 06/16/2017] [Indexed: 01/09/2023]
Abstract
The clinical challenge of percutaneous coronary interventions (PCI) is highly dependent on the recognition of the coronary anatomy of each individual. The classic imaging modality used for PCI is angiography, but advanced imaging techniques that are routinely performed during PCI, like optical coherence tomography (OCT), may provide detailed knowledge of the pre-intervention vessel anatomy as well as the post-procedural assessment of the specific stent-to-vessel interactions. Computational fluid dynamics (CFD) is an emerging investigational tool in the setting of optimization of PCI results. In this study, an OCT-based reconstruction method was developed for the execution of CFD simulations of patient-specific coronary artery models which include the actual geometry of the implanted stent. The method was applied to a rigid phantom resembling a stented segment of the left anterior descending coronary artery. The segmentation algorithm was validated against manual segmentation. A strong correlation was found between automatic and manual segmentation of lumen in terms of area values. Similarity indices resulted >96% for the lumen segmentation and >77% for the stent strut segmentation. The 3D reconstruction achieved for the stented phantom was also assessed with the geometry provided by X-ray computed micro tomography scan, used as ground truth, and showed the incidence of distortion from catheter-based imaging techniques. The 3D reconstruction was successfully used to perform CFD analyses, demonstrating a great potential for patient-specific investigations. In conclusion, OCT may represent a reliable source for patient-specific CFD analyses which may be optimized using dedicated automatic segmentation algorithms.
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Affiliation(s)
- Susanna Migliori
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy.
| | - Claudio Chiastra
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy
| | - Marco Bologna
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy; Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Eros Montin
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Gabriele Dubini
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy
| | - Cristina Aurigemma
- Institute of Cardiology, Catholic University of the Sacred Heart, Rome, Italy
| | - Roberto Fedele
- Department of Civil and Environmental Engineering, Politecnico di Milano, Milan, Italy
| | - Francesco Burzotta
- Institute of Cardiology, Catholic University of the Sacred Heart, Rome, Italy
| | - Luca Mainardi
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Francesco Migliavacca
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy.
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13
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Zerva K, Sanidas E, Tzanis G, Chantziara V, Papadopoulos D, Barbetseas J. Effect of thrombolytic therapy in plaque inflammation and structural remodeling in acute myocardial infarction patients. Hellenic J Cardiol 2017; 58:446-449. [PMID: 28600170 DOI: 10.1016/j.hjc.2017.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 05/24/2017] [Accepted: 06/01/2017] [Indexed: 11/19/2022] Open
Affiliation(s)
- Kanella Zerva
- Dept. of Cardiology, Laiko General Hospital, Athens, Greece
| | - Elias Sanidas
- Dept. of Cardiology, Laiko General Hospital, Athens, Greece.
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14
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Synetos A, Papaioannou S, Tousoulis D. Atherosclerosis and inflammation. Clinical aspects of a modern tale. Hellenic J Cardiol 2017; 58:122-123. [DOI: 10.1016/j.hjc.2017.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022] Open
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15
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Eshtehardi P, Brown AJ, Bhargava A, Costopoulos C, Hung OY, Corban MT, Hosseini H, Gogas BD, Giddens DP, Samady H. High wall shear stress and high-risk plaque: an emerging concept. Int J Cardiovasc Imaging 2017; 33:1089-1099. [PMID: 28074425 DOI: 10.1007/s10554-016-1055-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 12/26/2016] [Indexed: 12/30/2022]
Abstract
In recent years, there has been a significant effort to identify high-risk plaques in vivo prior to acute events. While number of imaging modalities have been developed to identify morphologic characteristics of high-risk plaques, prospective natural-history observational studies suggest that vulnerability is not solely dependent on plaque morphology and likely involves additional contributing mechanisms. High wall shear stress (WSS) has recently been proposed as one possible causative factor, promoting the development of high-risk plaques. High WSS has been shown to induce specific changes in endothelial cell behavior, exacerbating inflammation and stimulating progression of the atherosclerotic lipid core. In line with experimental and autopsy studies, several human studies have shown associations between high WSS and known morphological features of high-risk plaques. However, despite increasing evidence, there is still no longitudinal data linking high WSS to clinical events. As the interplay between atherosclerotic plaque, artery, and WSS is highly dynamic, large natural history studies of atherosclerosis that include WSS measurements are now warranted. This review will summarize the available clinical evidence on high WSS as a possible etiological mechanism underlying high-risk plaque development.
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Affiliation(s)
- Parham Eshtehardi
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA
| | - Adam J Brown
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Ankit Bhargava
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA
| | - Charis Costopoulos
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Olivia Y Hung
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA
| | - Michel T Corban
- Department of Cardiology, Mayo Clinic School of Medicine, Rochester, MN, USA
| | - Hossein Hosseini
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA
| | - Bill D Gogas
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA
| | - Don P Giddens
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Habib Samady
- Division of Cardiology, Department of Medicine, Emory University School of Medicine, 1364 Clifton Road F622, Atlanta, GA, 30322, USA.
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Tousoulis D. The evolution in the management of aortic valve disease: From surgical techniques to transcatheter interventions. Hellenic J Cardiol 2016; 57:379-381. [DOI: 10.1016/j.hjc.2017.03.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 12/14/2016] [Indexed: 12/19/2022] Open
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