A5050748142- Cardiovascular Function and Risk Factors
- Aortic Disease and Treatment Approaches
- Coronary Interventions and Diagnostics
- Advanced Numerical Methods in Computational Mathematics
- Aortic aneurysm repair treatments
- Cardiac Valve Diseases and Treatments
- Cardiac Imaging and Diagnostics
- Elasticity and Material Modeling
- Cardiovascular Health and Disease Prevention
- Model Reduction and Neural Networks
- Lattice Boltzmann Simulation Studies
- Cardiac electrophysiology and arrhythmias
- Low-power high-performance VLSI design
- Advanced MRI Techniques and Applications
- Reservoir Engineering and Simulation Methods
- Oil and Gas Production Techniques
- Analog and Mixed-Signal Circuit Design
- Intracranial Aneurysms: Treatment and Complications
- Cardiac and Coronary Surgery Techniques
- Computational Fluid Dynamics and Aerodynamics
- Advanced X-ray and CT Imaging
- Organ Transplantation Techniques and Outcomes
- 3D Shape Modeling and Analysis
- Fluid Dynamics Simulations and Interactions
- Advanced Numerical Analysis Techniques
King's College London
2016-2021
St Thomas' Hospital
2016-2021
Kings Health Partners
2016-2017
University of Oxford
2012-2013
Chaste — Cancer, Heart And Soft Tissue Environment is an open source C++ library for the computational simulation of mathematical models developed physiology and biology. Code development has been driven by two initial applications: cardiac electrophysiology cancer development. A large number studies have enabled performed, including high-performance investigations defibrillation on realistic human geometries. New initiation growth tumours developed. In particular, cell-based simulations...
Computational fluid dynamics (CFD) provides a noninvasive method to functionally assess aortic hemodynamics. The thoracic aorta has an anatomically complex inlet comprising of the valve and root, which is highly prone different morphologies pathologies. We investigated effect using patient-specific (PS) inflow velocity profiles compared idealized based on patient's flow waveform. A healthy 31 yo with normally functioning tricuspid (subject A), 52 bicuspid (BAV), valvular stenosis, dilated...
In this work, we describe the CRIMSON (CardiovasculaR Integrated Modelling and SimulatiON) software environment. provides a powerful, customizable user-friendly system for performing three-dimensional reduced-order computational haemodynamics studies via pipeline which involves: 1) segmenting vascular structures from medical images; 2) constructing analytic arterial venous geometric models; 3) finite element mesh generation; 4) designing, 5) applying boundary conditions; 6) running...
Abstract Coronary Artery Disease (CAD) is commonly diagnosed using X-ray angiography, in which images are taken as radio-opaque dye flushed through the coronary vessels to visualize severity of vessel narrowing, or stenosis. Cardiologists typically use visual estimation approximate percent diameter reduction stenosis, and this directs therapies like stent placement. A fully automatic method segment would eliminate potential subjectivity provide a quantitative systematic measurement...
Abstract OBJECTIVES Current endografts for thoracic endovascular aortic repair (TEVAR) are much stiffer than the aorta and have been shown to induce acute stiffening. In this study, we aimed estimate impact of TEVAR on left ventricular (LV) stroke work (SW) mass using a non-invasive image-based workflow. METHODS The University Michigan database was searched patients treated with descending pathologies (2013–2016). Patients available pre-TEVAR post-TEVAR computed tomography angiography...
The goal of this work is to train a neural network which approximates solutions the Navier-Stokes equations across region parameter space, in parameters define physical properties such as domain shape and boundary conditions. contributions are threefold: 1) To demonstrate that networks can be efficient aggregators whole families parameteric problems, trained using data created with traditional, trusted numerical methods finite elements. Advantages include extremely fast evaluation pressure...
Aortic arch repair remains a major surgical challenge. Multiple manufacturers are developing branched endografts for Zone 0 endovascular repair, extending the armamentarium minimally invasive treatment of aortic pathologies. We hypothesize that design endograft has significant impact on postoperative haemodynamic performance, particularly in cervical arteries. The goal our study was to compare performance different designs. Patient-specific, clinically validated, computational fluid dynamics...
This work presents a mathematical model of the metabolic feedback and adrenergic feedforward control coronary blood flow that occur during variations in cardiac workload. It is based on physiological observations closely follows myocardial oxygen demand, debts are repaid, oscillations when system perturbed so phenomenological nature. Using clinical data, we demonstrate can provide patient-specific estimates changes between rest exercise, requiring only patient's heart rate peak aortic...
We present an application of high order hierarchical finite elements for the efficient approximation solutions to cardiac monodomain problem. detail hurdles which must be overcome in achieve theoretically-optimal errors approximations generated, including choice method approximating solution cell model component. place our work on a solid theoretical foundation and show that it can greatly improve accuracy achieved given amount processor time. Our results demonstrate superior over linear at...
Abstract A major challenge in constructing three dimensional patient specific hemodynamic models is the calibration of model parameters to match data on flow, pressure, wall motion, etc. acquired clinic. Current workflows are manual and time-consuming. This work presents a flexible computational framework for parameter estimation cardiovascular flows that relies following fundamental contributions. (i) Reduced-Order Unscented Kalman Filter (ROUKF) assimilation material simple lumped network...
For babies born with hypoplastic left heart syndrome, several open-heart surgeries are required. During Stage I, a Norwood procedure is performed to construct an appropriate circulation both the systemic and pulmonary arteries. The arteries receive flow from circulation, often using Blalock-Taussig (BT) shunt between innominate artery right artery. This causes significantly disturbed in In this study, we use computational hemodynamic simulations demonstrate its capacity for examining...
Abstract In this paper, we perform a verification study of the Coupled‐Momentum Method (CMM), 3D fluid‐structure interaction (FSI) model which uses thin linear elastic membrane and kinematics to describe mechanical behavior vessel wall. The is done using Womersley's deformable wall analytical solution for pulsatile flow in semi‐infinite cylindrical vessel. This is, under certain premises, CMM can thus be used verification. For numerical solution, employ an impedance boundary condition define...
Objectives Cardiac output (CO) response to dobutamine can identify Alagille's syndrome (ALGS) patients at higher risk of cardiovascular complications during liver transplantation. We propose a novel patient-specific computational methodology estimate the coronary autoregulatory responses different hemodynamic conditions, including those experienced in post-reperfusion (PRS), aid cardiac risk-assessment. Material and methods Data (pressure, flow, strain ventricular volumes) from 6-year-old...
Abstract In this work, we describe the CRIMSON (CardiovasculaR Integrated Modelling and SimulatiON) software environment. provides a powerful, customizable user-friendly system for performing three-dimensional reduced-order computational haemodynamics studies via pipeline which involves: 1) segmenting vascular structures from medical images; 2) constructing analytic arterial venous geometric models; 3) finite element mesh generation; 4) designing, 5) applying boundary conditions; 6) running...
Numerical simulations of cardiovascular mass transport pose significant challenges due to the wide range P\'eclet numbers and backflow at Neumann boundaries. In this paper we present discuss several numerical tools address these in context a stabilized finite element computational framework. To overcome instabilities when occurs boundaries, propose an approach based on prescription total flux. addition, introduce "consistent flux" outflow boundary condition demonstrate its superior...
A bstract Coronary Artery Disease (CAD) is commonly diagnosed using X-ray angiography, in which images are taken as radio-opaque dye flushed through the coronary vessels to visualize stenosis severity. Cardiologists typically use visual estimation approximate percent diameter reduction of stenosis, and this directs therapies like stent placement. fully automatic method segment would eliminate potential subjectivity provide a quantitative systematic measurement reduction. Here, we have...
We propose a novel method to map patient-specific blood velocity profiles obtained from imaging data such as 2D flow MRI or 3D colour Doppler ultrasound) geometric vascular models suitable perform CFD simulations of haemodynamics. describe the implementation and utilisation within an open-source computational hemodynamics simulation software (CRIMSON).
Modern imaging techniques provide evermore-detailed anatomical and physiological information for use in computational fluid dynamics to predict the behaviour of phenomena. Computer modelling can help plan suitable interventions. Our group used magnetic resonance study haemodynamic variables ascending aorta patients with bicuspid aortic valve before after isolated tissue replacement. requires turning a model into mathematical one, solvable by equations that undergo multiple iterations four...