1
|
Petkantchin R, Rousseau A, Eker O, Zouaoui Boudjeltia K, Raynaud F, Chopard B. A simplified mesoscale 3D model for characterizing fibrinolysis under flow conditions. Sci Rep 2023; 13:13681. [PMID: 37608073 PMCID: PMC10444897 DOI: 10.1038/s41598-023-40973-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 08/19/2023] [Indexed: 08/24/2023] Open
Abstract
One of the routine clinical treatments to eliminate ischemic stroke thrombi is injecting a biochemical product into the patient's bloodstream, which breaks down the thrombi's fibrin fibers: intravenous or intravascular thrombolysis. However, this procedure is not without risk for the patient; the worst circumstances can cause a brain hemorrhage or embolism that can be fatal. Improvement in patient management drastically reduced these risks, and patients who benefited from thrombolysis soon after the onset of the stroke have a significantly better 3-month prognosis, but treatment success is highly variable. The causes of this variability remain unclear, and it is likely that some fundamental aspects still require thorough investigations. For that reason, we conducted in vitro flow-driven fibrinolysis experiments to study pure fibrin thrombi breakdown in controlled conditions and observed that the lysis front evolved non-linearly in time. To understand these results, we developed an analytical 1D lysis model in which the thrombus is considered a porous medium. The lytic cascade is reduced to a second-order reaction involving fibrin and a surrogate pro-fibrinolytic agent. The model was able to reproduce the observed lysis evolution under the assumptions of constant fluid velocity and lysis occurring only at the front. For adding complexity, such as clot heterogeneity or complex flow conditions, we propose a 3-dimensional mesoscopic numerical model of blood flow and fibrinolysis, which validates the analytical model's results. Such a numerical model could help us better understand the spatial evolution of the thrombi breakdown, extract the most relevant physiological parameters to lysis efficiency, and possibly explain the failure of the clinical treatment. These findings suggest that even though real-world fibrinolysis is a complex biological process, a simplified model can recover the main features of lysis evolution.
Collapse
Affiliation(s)
- Remy Petkantchin
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Geneva, Switzerland.
- Complex System Modeling Group, Computer Science Department, University of Geneva, Geneva, Switzerland.
| | - Alexandre Rousseau
- Laboratory of Experimental Medicine (ULB222), Faculty of Medicine, Université libre de Bruxelles, CHU de Charleroi, Charleroi, Belgium
| | - Omer Eker
- Department of Neuroradiology, Hôpital Pierre Wertheimer, Hospices Civils de Lyon, Lyon, France
- CREATIS Laboratory, UMR 5220, U1206, Université Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, Lyon, France
| | - Karim Zouaoui Boudjeltia
- Laboratory of Experimental Medicine (ULB222), Faculty of Medicine, Université libre de Bruxelles, CHU de Charleroi, Charleroi, Belgium
| | - Franck Raynaud
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Geneva, Switzerland
- Complex System Modeling Group, Computer Science Department, University of Geneva, Geneva, Switzerland
| | - Bastien Chopard
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Geneva, Switzerland
- Complex System Modeling Group, Computer Science Department, University of Geneva, Geneva, Switzerland
| |
Collapse
|
2
|
Qureshi A, Lip GYH, Nordsletten DA, Williams SE, Aslanidi O, de Vecchi A. Imaging and biophysical modelling of thrombogenic mechanisms in atrial fibrillation and stroke. Front Cardiovasc Med 2023; 9:1074562. [PMID: 36733827 PMCID: PMC9887999 DOI: 10.3389/fcvm.2022.1074562] [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: 10/19/2022] [Accepted: 12/29/2022] [Indexed: 01/18/2023] Open
Abstract
Atrial fibrillation (AF) underlies almost one third of all ischaemic strokes, with the left atrial appendage (LAA) identified as the primary thromboembolic source. Current stroke risk stratification approaches, such as the CHA2DS2-VASc score, rely mostly on clinical comorbidities, rather than thrombogenic mechanisms such as blood stasis, hypercoagulability and endothelial dysfunction-known as Virchow's triad. While detection of AF-related thrombi is possible using established cardiac imaging techniques, such as transoesophageal echocardiography, there is a growing need to reliably assess AF-patient thrombogenicity prior to thrombus formation. Over the past decade, cardiac imaging and image-based biophysical modelling have emerged as powerful tools for reproducing the mechanisms of thrombogenesis. Clinical imaging modalities such as cardiac computed tomography, magnetic resonance and echocardiographic techniques can measure blood flow velocities and identify LA fibrosis (an indicator of endothelial dysfunction), but imaging remains limited in its ability to assess blood coagulation dynamics. In-silico cardiac modelling tools-such as computational fluid dynamics for blood flow, reaction-diffusion-convection equations to mimic the coagulation cascade, and surrogate flow metrics associated with endothelial damage-have grown in prevalence and advanced mechanistic understanding of thrombogenesis. However, neither technique alone can fully elucidate thrombogenicity in AF. In future, combining cardiac imaging with in-silico modelling and integrating machine learning approaches for rapid results directly from imaging data will require development under a rigorous framework of verification and clinical validation, but may pave the way towards enhanced personalised stroke risk stratification in the growing population of AF patients. This Review will focus on the significant progress in these fields.
Collapse
Affiliation(s)
- Ahmed Qureshi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,*Correspondence: Ahmed Qureshi,
| | - Gregory Y. H. Lip
- Liverpool Centre for Cardiovascular Science, University of Liverpool and Liverpool Heart & Chest Hospital, Liverpool, United Kingdom
| | - David A. Nordsletten
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
| | - Oleg Aslanidi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Adelaide de Vecchi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| |
Collapse
|
3
|
Petkantchin R, Padmos R, Boudjeltia KZ, Raynaud F, Chopard B. Thrombolysis: Observations and numerical models. J Biomech 2021; 132:110902. [PMID: 34998180 DOI: 10.1016/j.jbiomech.2021.110902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 08/25/2021] [Accepted: 11/08/2021] [Indexed: 11/16/2022]
Abstract
This perspective paper considers thrombolysis in the context of ischemic strokes, intending to build eventually a numerical model capable of simulating the thrombolytic treatment and predicting patient outcomes. Numerical modeling is a scientific methodology based on an abstraction of a system but requires understanding their spatio-temporal interactions. However, although important, the current knowledge on thrombolysis is fragmented in contributions from which it is difficult to obtain a complete picture of the process, especially in a clinically relevant setup. This paper discusses, from a general point of view, how to develop a numerical model to describe the evolution of a patient clot under the action of a thrombolytic drug. We will present critical, yet fundamental, open questions that have emerged during this elaboration and discuss original experimental observations that challenge some of our current knowledge of thrombolysis.
Collapse
Affiliation(s)
- Remy Petkantchin
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Switzerland.
| | - Raymond Padmos
- Computational Science Laboratory, Institute for Informatics, Faculty of Science, University of Amsterdam, The Netherlands
| | - Karim Zouaoui Boudjeltia
- Laboratory of Experimental Medicine (ULB222), Faculty of Medicine, Université libre de Bruxelles, CHU de Charleroi, Belgium
| | - Franck Raynaud
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Switzerland
| | - Bastien Chopard
- Scientific and Parallel Computing Group, Computer Science Department, University of Geneva, Switzerland
| |
Collapse
|
4
|
Bannish BE, Hudson NE. The Utility and Potential of Mathematical Models in Predicting Fibrinolytic Outcomes. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2021; 20:100337. [PMID: 34957356 PMCID: PMC8694003 DOI: 10.1016/j.cobme.2021.100337] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The enzymatic degradation of blood clots, fibrinolysis, is an important part of a healthy hemostatic system. If intrinsic fibrinolysis is ineffective, thrombolysis - the clinically-induced enzymatic degradation of blood clots - may be necessary to treat life-threatening conditions. In this review we discuss recent models of fibrinolysis and thrombolysis, and open questions that could be resolved through modeling and modeling-experimental collaboration. In particular, we focus on 2- and 3-dimensional models that can be used to study effects of fibrin network structure and realistic blood vessel geometries on the phenomena underlying lytic outcomes. Significant open questions such as the role of clot contraction, network and inherent fiber tension, and fibrinolytic inhibitors in lysis could benefit from mathematical models aimed at understanding the underlying biological mechanisms.
Collapse
Affiliation(s)
- Brittany E. Bannish
- Department of Mathematics and Statistics, University of Central Oklahoma, Edmond, OK 73034, USA
- Center for Interdisciplinary Biomedical Education and Research, University of Central Oklahoma, Edmond, OK 73034, USA
| | - Nathan E. Hudson
- Nathan E. Hudson, Department of Physics, East Carolina University, Greenville, NC 27858, USA
| |
Collapse
|
5
|
Teeraratkul C, Mukherjee D. Microstructure aware modeling of biochemical transport in arterial blood clots. J Biomech 2021; 127:110692. [PMID: 34479090 DOI: 10.1016/j.jbiomech.2021.110692] [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] [Received: 03/04/2021] [Revised: 07/14/2021] [Accepted: 08/09/2021] [Indexed: 01/29/2023]
Abstract
Flow-mediated transport of biochemical species is central to thrombotic phenomena. Comprehensive three-dimensional modeling of flow-mediated transport around realistic macroscale thrombi poses challenges owing to their arbitrary heterogeneous microstructure. Here, we develop a microstructure aware model for species transport within and around a macroscale thrombus by devising a custom preconditioned fictitious domain formulation for thrombus-hemodynamics interactions, and coupling it with a fictitious domain advection-diffusion formulation for transport. Microstructural heterogeneities are accounted through a hybrid discrete particle-continuum approach for the thrombus interior. We present systematic numerical investigations on unsteady arterial flow within and around a three-dimensional macroscale thrombus; demonstrate the formation of coherent flow structures around the thrombus which organize advective transport; illustrate the role of the permeation processes at the thrombus boundary and subsequent intra-thrombus transport; and characterize species transport from bulk flow to the thrombus boundary and vice versa.
Collapse
Affiliation(s)
- Chayut Teeraratkul
- Paul M Rady Department of Mechanical Engineering, University of Colorado Boulder, United States of America.
| | - Debanjan Mukherjee
- Paul M Rady Department of Mechanical Engineering, University of Colorado Boulder, United States of America.
| |
Collapse
|
6
|
Raynaud F, Rousseau A, Monteyne D, Perez-Morga D, Zouaoui Boudjeltia K, Chopard B. Investigating the two regimes of fibrin clot lysis: an experimental and computational approach. Biophys J 2021; 120:4091-4106. [PMID: 34384765 PMCID: PMC8510862 DOI: 10.1016/j.bpj.2021.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/07/2021] [Accepted: 08/04/2021] [Indexed: 12/03/2022] Open
Abstract
It has been observed in vitro that complete clot lysis is generally preceded by a slow phase of lysis during which the degradation seems to be inefficient. However, this slow regime was merely noticed, but not yet quantitatively discussed. In our experiments, we observed that the lysis ubiquitously occurred in two distinct regimes, a slow and a fast lysis regime. We quantified extensively the duration of these regimes for a wide spectrum of experimental conditions and found that on average, the slow regime lasts longer than the fast one, meaning that during most of the process, the lysis is ineffective. We proposed a computational model in which the properties of the binding of the proteins change during the lysis: first, the biochemical reactions take place at the surface of the fibrin fibers, then in the bulk, resulting in the observed fast lysis regime. This simple hypothesis appeared to be sufficient to reproduce with a great accuracy the lysis profiles obtained experimentally.
Collapse
Affiliation(s)
- Franck Raynaud
- Department of Computer Science, University of Geneva, Geneva, Switzerland.
| | - Alexandre Rousseau
- Laboratoire de Médecine Expérimentale, Medicine Faculty, Université libre de Bruxelles (ULB 222 Unit), ISPPC CHU de Charleroi, Hôpital A. Vésale, Montigny-le-Tilleul, Belgium
| | - Daniel Monteyne
- Laboratory of Molecular Parasitology, IBMM, Université libre de Bruxelles, Gosselies, Belgium; Center for Microscopy and Molecular Imaging, Université libre de Bruxelles, Gosselies, Belgium
| | - David Perez-Morga
- Laboratory of Molecular Parasitology, IBMM, Université libre de Bruxelles, Gosselies, Belgium; Center for Microscopy and Molecular Imaging, Université libre de Bruxelles, Gosselies, Belgium
| | - Karim Zouaoui Boudjeltia
- Laboratoire de Médecine Expérimentale, Medicine Faculty, Université libre de Bruxelles (ULB 222 Unit), ISPPC CHU de Charleroi, Hôpital A. Vésale, Montigny-le-Tilleul, Belgium
| | - Bastien Chopard
- Department of Computer Science, University of Geneva, Geneva, Switzerland
| |
Collapse
|
7
|
Li H, Sampani K, Zheng X, Papageorgiou DP, Yazdani A, Bernabeu MO, Karniadakis GE, Sun JK. Predictive modelling of thrombus formation in diabetic retinal microaneurysms. ROYAL SOCIETY OPEN SCIENCE 2020; 7:201102. [PMID: 32968536 PMCID: PMC7481715 DOI: 10.1098/rsos.201102] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/29/2020] [Indexed: 06/11/2023]
Abstract
Microaneurysms (MAs) are one of the earliest clinically visible signs of diabetic retinopathy (DR). Vision can be reduced at any stage of DR by MAs, which may enlarge, rupture and leak fluid into the neural retina. Recent advances in ophthalmic imaging techniques enable reconstruction of the geometries of MAs and quantification of the corresponding haemodynamic metrics, such as shear rate and wall shear stress, but there is lack of computational models that can predict thrombus formation in individual MAs. In this study, we couple a particle model to a continuum model to simulate the platelet aggregation in MAs with different shapes. Our simulation results show that under a physiologically relevant blood flow rate, thrombosis is more pronounced in saccular-shaped MAs than fusiform-shaped MAs, in agreement with recent clinical findings. Our model predictions of the size and shape of the thrombi in MAs are consistent with experimental observations, suggesting that our model is capable of predicting the formation of thrombus for newly detected MAs. This is the first quantitative study of thrombosis in MAs through simulating platelet aggregation, and our results suggest that computational models can be used to predict initiation and development of intraluminal thrombus in MAs as well as provide insights into their role in the pathophysiology of DR.
Collapse
Affiliation(s)
- He Li
- Division of Applied Mathematics, Brown University, Providence, RI 02912, USA
| | - Konstantina Sampani
- Beetham Eye Institute, Joslin Diabetes Center, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Xiaoning Zheng
- Division of Applied Mathematics, Brown University, Providence, RI 02912, USA
| | - Dimitrios P. Papageorgiou
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alireza Yazdani
- Division of Applied Mathematics, Brown University, Providence, RI 02912, USA
| | - Miguel O. Bernabeu
- Centre for Medical Informatics, Usher Institute, University of Edinburgh, Edinburgh, UK
| | | | - Jennifer K. Sun
- Beetham Eye Institute, Joslin Diabetes Center, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
8
|
Gu B, Piebalgs A, Huang Y, Roi D, Lobotesis K, Longstaff C, Hughes AD, Chen R, Thom SA, Xu XY. Computational simulations of thrombolysis in acute stroke: Effect of clot size and location on recanalisation. Med Eng Phys 2019; 73:9-17. [PMID: 31402315 DOI: 10.1016/j.medengphy.2019.07.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/03/2019] [Accepted: 07/28/2019] [Indexed: 11/28/2022]
Abstract
Acute ischaemic stroke can be treated by intravenous thrombolysis whereby tissue plasminogen activator (tPA) is infused to dissolve clots that block blood supply to the brain. In this study, we aim to examine the influence of clot location and size on lysis pattern and recanalisation by using a recently developed computational modelling framework for thrombolysis under physiological flow conditions. An image-based patient-specific model is reconstructed which consists of the internal carotid bifurcation with the A1 segment of anterior cerebral arteries and M1 segment of middle cerebral arteries, and the M1 bifurcation containing the M2 segments. By varying the clot size and location, 7 scenarios are simulated mimicking thrombolysis of M1 and M2 occlusions. Our results show that initial breakthrough always occurs along the inner curvature of the occluded cerebral artery, due to prolonged tPA residence time in the recirculation zone. For a given occlusion site, lysis completion time appears to increase almost quadratically with the initial clot volume; whereas for a given clot volume, the simulated M2 occlusions take up to 30% longer for complete lysis compared to the corresponding M1 occlusions.
Collapse
Affiliation(s)
- Boram Gu
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Andris Piebalgs
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Yu Huang
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Dylan Roi
- Imaging Department, Charing Cross Hospital, Imperial College Healthcare NHS Trust, London W6 8RF, United Kingdom
| | - Kyriakos Lobotesis
- Imaging Department, Charing Cross Hospital, Imperial College Healthcare NHS Trust, London W6 8RF, United Kingdom
| | - Colin Longstaff
- Biotherapeutics Section, National Institute for Biological Standards and Control, South Mimms, Herts, United Kingdom
| | - Alun D Hughes
- Institute of Cardiovascular Science, University College London, London, United Kingdom; MRC Unit for Lifelong Health and Ageing at University College London, London, United Kingdom
| | - Rongjun Chen
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Simon A Thom
- National Heart and Lung Institute, Imperial College London, Hammersmith Campus, London, United Kingdom
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, United Kingdom.
| |
Collapse
|
9
|
Piebalgs A, Gu B, Roi D, Lobotesis K, Thom S, Xu XY. Computational Simulations of Thrombolytic Therapy in Acute Ischaemic Stroke. Sci Rep 2018; 8:15810. [PMID: 30361673 PMCID: PMC6202379 DOI: 10.1038/s41598-018-34082-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 10/10/2018] [Indexed: 11/09/2022] Open
Abstract
Ischaemic stroke can occur when an artery to the brain is blocked by a blood clot. The use of thrombolytic agents, such as tissue plasminogen activator (tPA), to dissolve the occluding clot is limited by the risk of intracerebral haemorrhage (ICH), a known side effect associated with tPA. We developed a computational thrombolysis model for a 3D patient-specific artery coupled with a compartmental model for temporal concentrations of tPA and lysis proteins during intravenous infusion of tPA, in order to evaluate the effects of tPA dose on the efficacy of thrombolytic therapy and the risk of ICH. The model was applied to a 3-mm-long fibrin clot with two different fibrin fibre radii in the middle cerebral artery (MCA) - a setting relevant to ischaemic stroke, and results for different tPA dose levels and fibrin fibre radii were compared. Our simulation results showed that clot lysis was accelerated at higher tPA doses at the expense of a substantial increase in the risk of ICH. It was also found that a fine clot with a smaller fibre radius dissolved much slowly than a coarse clot due to a slower tPA penetration into the clots.
Collapse
Affiliation(s)
- Andris Piebalgs
- Faculty of Engineering, Department of Chemical Engineering, South Kensington Campus, Imperial College London, London, SW7 2AZ, United Kingdom
| | - Boram Gu
- Faculty of Engineering, Department of Chemical Engineering, South Kensington Campus, Imperial College London, London, SW7 2AZ, United Kingdom
| | - Dylan Roi
- Imaging Department, Charing Cross Hospital, Imperial College Healthcare NHS Trust, London, W6 8RF, United Kingdom
| | - Kyriakos Lobotesis
- Imaging Department, Charing Cross Hospital, Imperial College Healthcare NHS Trust, London, W6 8RF, United Kingdom
| | - Simon Thom
- Faculty of Medicine, National Heart & Lung Institute, Hammersmith Campus, Imperial College London, London, W12 0NN, United Kingdom
| | - Xiao Yun Xu
- Faculty of Engineering, Department of Chemical Engineering, South Kensington Campus, Imperial College London, London, SW7 2AZ, United Kingdom.
| |
Collapse
|
10
|
Kaesmacher J, Mosimann PJ, Giarrusso M, El-Koussy M, Zibold F, Piechowiak E, Dobrocky T, Meier R, Jung S, Bellwald S, Arnold M, Mordasini P, Fischer U, Gralla J. Multivessel Occlusion in Patients Subjected to Thrombectomy: Prevalence, Associated Factors, and Clinical Implications. Stroke 2018; 49:1355-1362. [PMID: 29769241 DOI: 10.1161/strokeaha.118.021276] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 03/21/2018] [Accepted: 03/30/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Patients with embolic large-vessel occlusion may present with additional coincidental acute occlusions within or distant from the involved territory, referred to as multivessel occlusion (MVO). Purpose of this study was to assess prevalence of MVO, associated factors, and clinical relevance in patients undergoing endovascular stroke treatment. METHODS Image data of consecutive endovascular candidates (n=720) with direct access to angiography were extracted from a prospective registry. Prevalence of MVO was assessed with multimodal magnetic resonance imaging/computed tomography and confirmed by intra-arterial angiography. Explorative analysis of associated factors and clinical relevance was evaluated using multivariable logistic regression including variables with P<0.15 in univariate comparison. Good functional outcome was defined as modified Rankin Scale score ≤2 at day 90. RESULTS MVO was present in 10.7% of patients (95% confidence interval [CI], 6.4%-13.0%). Two, 3, and 4 concomitant occlusions were found in 80.5%, 16.9%, and 2.6% of MVO cases, respectively. Detection rate on initial radiological report was 54.5%. Downstream MVO was present in around one third of MVO (n=27/77, 35.1%), whereas all other MVO (n=50/77, 64.9%) occurred in different territories. Independent factors related to MVO were statin treatment (adjusted odds ratio [aOR], 0.477; 95% CI, 0.276-0.827), higher systolic blood pressure (aOR per mm Hg increase, 1.014; 95% CI, 1.005-1.023), and primary occlusion site M2 (aOR, 1.870; 95% CI, 1.103-3.170). MVO was related to lower rates of successful reperfusion (aOR, 0.549; 95% CI, 0.316-0.953) and lower rates of good functional outcome (aOR, 0.437; 95% CI, 0.207-0.923). CONCLUSIONS Every tenth patient subjected to angiography for endovascular stroke treatment experienced MVO in our series, and only half were prospectively identified on preinterventional diagnostic imaging. Patients with MVO had higher baseline systolic blood pressure and were less often medicated with statins, an observation that warrants external validation and evaluation regarding causality. Occurrence of MVO has implication for treatment decisions, negatively affects endovascular treatment success, and is predictive of worse clinical outcome.
Collapse
Affiliation(s)
- Johannes Kaesmacher
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.).,Department of Neurology (J.K., M.G., S.J., S.B., M.A., U.F.)
| | - Pascal J Mosimann
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | | | - Marwan El-Koussy
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | - Felix Zibold
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | - Eike Piechowiak
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | - Tomas Dobrocky
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | - Raphael Meier
- Support Center for Advanced Neuroimaging (R.M.), University of Bern, Inselspital, Switzerland
| | - Simon Jung
- Department of Neurology (J.K., M.G., S.J., S.B., M.A., U.F.)
| | - Sebastian Bellwald
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.).,Department of Neurology (J.K., M.G., S.J., S.B., M.A., U.F.)
| | - Marcel Arnold
- Department of Neurology (J.K., M.G., S.J., S.B., M.A., U.F.)
| | - Pasquale Mordasini
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| | - Urs Fischer
- Department of Neurology (J.K., M.G., S.J., S.B., M.A., U.F.)
| | - Jan Gralla
- From the University Institute of Diagnostic and Interventional Neuroradiology (J.K., P.J.M., M.E.-K., F.Z., E.P., T.D., S.B., P.M., J.G.)
| |
Collapse
|
11
|
Hudson NE. Biophysical Mechanisms Mediating Fibrin Fiber Lysis. BIOMED RESEARCH INTERNATIONAL 2017; 2017:2748340. [PMID: 28630861 PMCID: PMC5467299 DOI: 10.1155/2017/2748340] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 04/30/2017] [Indexed: 01/19/2023]
Abstract
The formation and dissolution of blood clots is both a biochemical and a biomechanical process. While much of the chemistry has been worked out for both processes, the influence of biophysical properties is less well understood. This review considers the impact of several structural and mechanical parameters on lytic rates of fibrin fibers. The influences of fiber and network architecture, fiber strain, FXIIIa cross-linking, and particle transport phenomena will be assessed. The importance of the mechanical aspects of fibrinolysis is emphasized, and future research avenues are discussed.
Collapse
Affiliation(s)
- Nathan E. Hudson
- Department of Physics, East Carolina University, N304 Howell Science Complex, Greenville, NC 27858, USA
| |
Collapse
|
12
|
Yesudasan S, Wang X, Averett RD. Molecular dynamics simulations indicate that deoxyhemoglobin, oxyhemoglobin, carboxyhemoglobin, and glycated hemoglobin under compression and shear exhibit an anisotropic mechanical behavior. J Biomol Struct Dyn 2017; 36:1417-1429. [PMID: 28441918 DOI: 10.1080/07391102.2017.1323674] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We developed a new mechanical model for determining the compression and shear mechanical behavior of four different hemoglobin structures. Previous studies on hemoglobin structures have focused primarily on overall mechanical behavior; however, this study investigates the mechanical behavior of hemoglobin, a major constituent of red blood cells, using steered molecular dynamics (SMD) simulations to obtain anisotropic mechanical behavior under compression and shear loading conditions. Four different configurations of hemoglobin molecules were considered: deoxyhemoglobin (deoxyHb), oxyhemoglobin (HbO2), carboxyhemoglobin (HbCO), and glycated hemoglobin (HbA1C). The SMD simulations were performed on the hemoglobin variants to estimate their unidirectional stiffness and shear stiffness. Although hemoglobin is structurally denoted as a globular protein due to its spherical shape and secondary structure, our simulation results show a significant variation in the mechanical strength in different directions (anisotropy) and also a strength variation among the four different hemoglobin configurations studied. The glycated hemoglobin molecule possesses an overall higher compressive mechanical stiffness and shear stiffness when compared to deoxyhemoglobin, oxyhemoglobin, and carboxyhemoglobin molecules. Further results from the models indicate that the hemoglobin structures studied possess a soft outer shell and a stiff core based on stiffness.
Collapse
Affiliation(s)
- Sumith Yesudasan
- a School of Chemical, Materials, and Biomedical Engineering , College of Engineering, University of Georgia , 597 D.W. Brooks Drive, Athens , GA 30602 , USA
| | - Xianqiao Wang
- b School of Environmental, Civil, Agricultural and Mechanical Engineering , College of Engineering, University of Georgia , 712G Boyd Graduate Studies Research Center, Athens , GA 30602 , USA
| | - Rodney D Averett
- a School of Chemical, Materials, and Biomedical Engineering , College of Engineering, University of Georgia , 597 D.W. Brooks Drive, Athens , GA 30602 , USA
| |
Collapse
|
13
|
Gray F, Cen J, Boek ES. Simulation of dissolution in porous media in three dimensions with lattice Boltzmann, finite-volume, and surface-rescaling methods. Phys Rev E 2016; 94:043320. [PMID: 27841520 DOI: 10.1103/physreve.94.043320] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Indexed: 06/06/2023]
Abstract
We present a pore-scale dissolution model for the simulation of reactive transport in complex porous media such as those encountered in carbon-storage injection processes. We couple a lattice Boltzmann model for flow calculation with a finite-volume method for solving chemical transport equations, and allow the computational grid to change as mineral surfaces are dissolved according to first-order reaction kinetics. We appraise this scheme for use with high Péclet number flows in three-dimensional geometries and show how the popular first-order convection scheme is affected by severe numerical diffusion when grid Péclet numbers exceed unity, and confirm that this can be overcome relatively easily by using a second-order method in conjunction with a flux-limiter function. We then propose a surface rescaling method which uses parabolic elements to counteract errors in surface area exposed by the Cartesian grid and avoid the use of more complex embedded surface methods when surface reaction kinetics are incorporated. Finally, we compute dissolution in an image of a real porous limestone rock sample injected with HCl for different Péclet numbers and obtain dissolution patterns in concordance with theory and experimental observation. A low injection flow rate was shown to lead to erosion of the pore space concentrated at the face of the rock, whereas a high flow rate leads to wormhole formation.
Collapse
Affiliation(s)
- F Gray
- Qatar Carbonates and Carbon Storage Research Centre (QCCSRC), Department of Chemical Engineering, South Kensington Campus, Imperial College London, London SW7 2AZ, United Kingdom
| | - J Cen
- Science and Solutions for a Changing Planet DTP (SSCPDTP), Department of Chemical Engineering, South Kensington Campus, Imperial College London, London SW7 2AZ, United Kingdom
| | - E S Boek
- Qatar Carbonates and Carbon Storage Research Centre (QCCSRC), Department of Chemical Engineering, South Kensington Campus, Imperial College London, London SW7 2AZ, United Kingdom
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, United Kingdom
| |
Collapse
|