2024Activity reportProject-TeamCARMEN

3.1 Complex models for the propagation of cardiac action potentials

The contraction of the heart is coordinated by a complex electrical activation process which relies on about a million ion channels, pumps, and exchangers of various kinds in the membrane of each cardiac cell. Their interaction results in a periodic change in transmembrane potential called an action potential. Action potentials in the cardiac muscle propagate rapidly from cell to cell, synchronizing the contraction of the entire muscle to achieve an efficient pump function. The spatio-temporal pattern of this propagation is related both to the function of the cellular membrane and to the structural organization of the cells into tissues. Cardiac arrythmias originate from malfunctions in this process. The field of cardiac electrophysiology studies the multiscale organization of the cardiac activation process from the subcellular scale up to the scale of the body. It relates the molecular processes in the cell membranes to the propagation process through the multiscale structure of the tissue and organ, to measurable signals in the heart and to the electrocardiogram, an electrical signal on the torso surface.

Several improvements of current models of the propagation of action potentials are being developed in the Carmen team, based on previous work 43 and on the data available at IHU Liryc:

• Enrichment of the current monodomain and bidomain models 43, 54 by accounting for structural heterogeneities of the tissue at cellular and intermediate scales. Here we focus on multiscale analysis techniques applied to the various high-resolution structural data available at IHU Liryc.
• Coupling of the tissues from the different cardiac compartments and conduction systems. Here, we develop models that couple 1D, 2D and 3D phenomena described by reaction- diffusion PDEs.

These models are essential to improve our understanding of cardiac electrical dysfunction. To this aim, we use high-performance computing techniques in order to numerically explore the complexity of these models.

We use these model codes for applied studies in two important areas of cardiac electrophysiology: atrial fibrillation 45 and sudden-cardiac-death (SCD) syndromes 8, 748. This work is performed in collaboration with several physiologists and clinicians both at IHU Liryc and abroad.

3.2 Simplified models and inverse problems

The medical and clinical exploration of the cardiac electric signals is based on accurate reconstruction of the patterns of propagation of the action potential. The correct detection of these complex patterns by non-invasive electrical imaging techniques has to be developed. This involves solving inverse problems that cannot be addressed with the more complex models. We want both to develop simple and fast models of the propagation of cardiac action potentials and improve the solutions to the reconstruction questions of cardiac electrical imaging techniques.

These questions concern the reconstruction of diverse information, such as cardiac activation maps or, more generally, the whole cardiac electrical activity, from high-density body surface electrocardiograms. It is a possibly powerful diagnosis technique, which success would be considered as a breakthrough. Although widely studied during the last decade, the reconstructed activation maps, for instance, are highly inacurate and have a poor clinical interest. It remains a challenge for the scientific community to understand how body surface signals can better inform on the fine details of arrhythmic mechanisms.

The most usual method consists in solving a Laplace equation on the volume delimited by the body surface and the epicardial surface, for which we contribute by:

• studying in depth the dependance of the inverse problem on inhomogeneities in the torso, conductivity values, the geometry, electrode positions, etc., and
• improving the solution to the inverse problem by using new regularization strategies, factorization of boundary value problems, and the theory of optimal control.

In addition, we have started to explore many alternative approaches including:

• using complete propagation models in the inverse problem, like the bidomain or monodomain equations, for instance in order to localize electrical sources,
• constructing data-based models using e.g. statistical learning techniques, which would accurately represent some families of well-identified pathologies, or allow to combine physics and biology-informed models and clinical data, and
• constructing simpler models of the propagation of the activation front, based on eikonal or level-set equations.

3.3 Numerical techniques

We want our numerical simulations to be efficient, accurate, and reliable with respect to the needs of the medical community. Based on previous work on solving the monodomain and bidomain equations 5, 4, 9, 1, we will focus on:

• high-order numerical techniques with respect to the variables with physiological meaning, like velocity, AP duration and restitution properties and
• efficient, dedicated preconditioning techniques coupled with parallel computing.

Existing simulation tools used in our team rely, among others, on mixtures of explicit and implicit integration methods for ODEs, hybrid MPI-OpenMP parallellization, algebraic multigrid preconditioning, and Krylov solvers. New developments include high-order explicit integration methods and task-based dynamic parallellism.

3.4 Cardiac electrophysiology at the microscopic scale

Traditional numerical models of whole-heart physiology are based on the approximation of a perfect muscle using homogenisation methods. However, due to aging and cardiomyopathies, the cellular structure of the tissue changes. These modifications can give rise to life-threatening arrhythmias, the mechanisms of which we are investigating in collaboration with cardiologists at the IHU Liryc. For this research we are building models that describe the strong heterogeneity of the tissue at the cellular level.

The literature on this type of model is still very limited 60. Existing models are two-dimensional 49 or limited to idealized geometries, and use a linear (purely resistive) behaviour of the gap-juction channels that connect the cells. We propose a three-dimensional approach using realistic cellular geometry (Fig. 1), nonlinear gap-junction behaviour, and a numerical approach that can scale to hundreds of cells while maintaining a sub-micrometer spatial resolution (10 to 100 times smaller than the size of a cardiomyocyte). Following preliminary work in this area by us 39, 38, 37 and by others 60 we proposed a European project with 10 partner institutes and a 5.8M€ budget to develop software that can simulate such models, with micrometer resolution, on the scale of millions of cells, using future exascale supercomputers (microcard.eu). This project ran from April 2021 to October 2024, and involves also the Inria teams CAMUS, STORM and CARDAMOM as well as the Inria-led MMG Consortium.

Image of the microstructure from histology, current, insufficient, representation of microstructural defects, and foreseen geometry to be used in microscopic models.

The cell-by-cell bidomain model presents numerous mathematical and computational challenges. First, mathematically, its unusual formulation providing time dynamics as an ordinary differential equation (ODE) at the cell- to-cell connections and cell-to-extracellular matrix interfaces. Second, the ionic model coupled to the nonstandard transmission conditions, introduce stiff non linear dynamics. Third, the simulation would be performed for billions of myocytes, leading to extremely large systems. In the MICROCARD project, we simulate the micromodel using finite volumes, finite elements and boundary element methods. In November 2024 the project was succeeded by the Centre of Excellence MICROCARD-2, in which the Inria teams CARMEN, STORM, CAMUS and TADAAM are involved.

3.5 Models and tools for ablative therapies

Today, the most effective way to treat arrhythmias is to ablate selected regions of the cardiac tissue. The lesions are assumed electrically passive, and consequently create conduction blocks that stop the disorganized propagation of action potentials. The ablation procedure consists in placing a catheter in contact with the targeted site and deliver energy into the tissue. The energy can be overheating by radio-frequency current, electroporating electric pulses or temperature drop (cryotherapy). In practice, the choice of the ablation site is done by the clinician based on previous signal measurements and imagery, and is also guided during the procedure with real-time measurement of the electric signal.

Our team works on several subjects related to ablation techniques that may improve the success rate of the treatments:

• accurate computation of electric fields generated by catheters: complex catheter shapes, contact models, tissue heterogeneities;
• models of creation of the lesions, either through temperature rise (radio-frequency) or electroporation; and
• localization tools to help clinicians target the optimal ablation sites, based on both data of previously ablated patients and synthetic data.

4.1 Scientific context: IHU Liryc

The University Hospital of Bordeaux (CHU de Bordeaux) is equipped with a specialized cardiology hospital, the Hôpital Cardiologique du Haut-Lévêque, where the group of Professor Michel Haïssaguerre has established itself as a global leader in the field of cardiac electrophysiology 47, 46, 41. Their discoveries in the area of atrial fibrillation and sudden cardiac death syndromes are widely acclaimed, and the group is a national and international referral center for treatment of cardiac arrhythmia. Thus the group also sees large numbers of patients with rare cardiac diseases.

In 2011 the group has won the competition for a 40 million euro Investissements d'Avenir grant for the establishment of IHU Liryc, an institute that combines clinical, experimental, and numerical research in the area of cardiac arrhythmia. The institute works in all areas of modern cardiac electrophysiology: atrial arrhythmias, sudden death due to ventricular fibrillation, heart failure related to ventricular dyssynchrony, and metabolic disorders. It is recognized worldwide as one of the most important centers in this area.

The Carmen team was founded as a part of IHU Liryc. We bring applied mathematics and scientific computing closer to experimental and clinical cardiac electrophysiology. In collaboration with experimental and clinical researchers at Liryc we work to enhance fundamental knowledge of the normal and abnormal cardiac electrical activity and of the patterns of the electrocardiogram, and we develop new simulation tools for training, biological, and clinical applications.

4.2 Basic experimental electrophysiology

Our modeling is carried out in coordination with the experimental teams from IHU Liryc. It helps to write new concepts concerning the multiscale organisation of the cardiac action potentials that will serve our understanding in many electrical pathologies. For example, we model the structural heterogeneities at the cellular scale 40 (the MICROCARD project), and at an intermediate scale between the cellular and tissue scales.

At the atrial level, we apply our models to understand the mechanisms of complex arrythmias and the relation with the heterogeneities at the insertion of the pulmonary veins. We will model the heterogeneities specific to the atria, like fibrosis or fatty infiltration  56, 45. These heterogeneities are thought to play a major role in the development of atrial fibrillation.

At the ventricular level, we focus on (1) modeling the complex coupling between the Purkinje network and the ventricles, which is supposed to play a major role in sudden cardiac death, and (2) modeling the heteogeneities related to the complex organization and disorganization of the myocytes and fibroblasts, which is important in the study of infarct scars for instance.

4.3 Clinical electrophysiology

Treatment of cardiac arrhythmia is possible by pharmacological means, by implantation of pacemakers and defibrillators, and by curative ablation of diseased tissue by local heating, freezing or electroporation. In particular the ablative therapies create challenges that can be addressed by numerical means. Cardiologists would like to know, preferably by noninvasive means, where an arrhythmia originates and by what mechanism it is sustained.

We address this issue in the first place using inverse models, which attempt to estimate the cardiac activity from a (high-density) electrocardiogram. A new project aims to perform this estimation on-site in the catheterization laboratory and presenting the results, together with the cardiac anatomy, on the screen that the cardiologist uses to monitor the catheter positions 50, 35.

4.4 Application in Deep Brain Stimulation

Since 2017, we have been working with neurosurgeons from the Bordeaux University Hospital (Pr Cuny and Dr. Engelhardt) on improving the planning technique for deep brain surgery (DBS) for Parkinson's and Essential tremor diseases. DBS is the last resort to treat the symptoms of Parkinson's disease after the drug Levodopa. The surgery consists in placing electrodes in very specific regions of the patient's brain. These regions are unfortunately not visible on the 1.5 Tesla MRI, the most widely available MRI machines in hospitals. The most effective solution to date is to introduce 5 micro-electrodes (MER) to record the activity of neurons in the patient's brain and to prospect by moving the electrodes in order to find the best location. However, this approach renders the surgery very cumbersome because the patient must be awake during the exploration phase. In addition, this phase takes at least 3 hours and mobilizes a neurologist with his staff. The total duration of the operation is between 7 and 8 hours. Many elderly patients do not tolerate this surgery. We have proposed an approach that avoids the prospecting phase and performs surgery under general anesthesia. The idea is to learn on pairs of clinical landmarks and the position of active electrodes in order to predict the optimal position of the DBS from a pre-operative image. This approach simplifies and standardizes surgery planning. We tested several approaches, 6. We continue to seek approaches to fully automate the targeting process. We carried out a proof of concept by learning on the clinical database of the Bordeaux University Hospital. The clinical validation of our approach is in progress through a clinical trial which includes patients from the University Hospitals of Bordeaux and Lyon. Pr Cuny has submitted a phase 3 national clinical research hospital project (PHRCN) including 11 CHUs in France which has been accepted by the General Directorate for Care Offers (DGOS). The aim is to compare our new approach to the ones used in the other centers. Inria Bordeaux is a partner in this project and we maintain the OptimDBS software and solve any technical problem related to the compatibility of the MRIs exported by our software and the surgical robots in the different centers.

5.1 Footprint of research activities

We avoid flying whenever we can, and try to keep computers for 7 years, despite the fact that they are not supported by the DSI that long.

Lisl Weynans is involved in the creation of courses about environmental and social transition at Bordeaux University.

5.2 Impact of research results

The MICROCARD project and its successor MICROCARD-2, which we coordinate, has energy efficiency as one of its goals. To this end, our partners in the STORM and CAMUS teams are developing methods to increase the time- and energy-efficiency of cardiac simulation codes.

6.1 Awards

New professor at the University of Bordeaux: Lisl Weynans since September 2024

6.2 Major Funding

We obtained a 5M€ grant from the EuroHPC joint undertaking to establish the MICROCARD Centre of Excellence (administrative name: MICROCARD-2) for numerical modeling of cardiac electrophysiology at the cellular scale. Details on the project are given in section 10.

7.1 Evolution of existing software

• CEPS Our cardiac electrophysiology software CEPS received the following updates:
  • Thanks to the recruitment of Loïc Calvez, several optimization bottlenecks were removed, which already improved the performance of several runs by more than 30%.
  • Addition of the FDA benchmark for cardiac electrophysiology problems, as given in 52.
  • A new build system has been proposed by Xavier Muller, which should ease installation of CEPS, and be integrated in a release early 2025.
• OpenCarp is an open cardiac electrophysiology simulator for in-silico experiments (described below):
  • A command-line tool is now available to visualize images of cross sections of .mesh/.sol combinations to obtain fly-through movies.

7.2 New software

7.3 New platforms

Participants: Mark Potse, Andony Arrieula, Laetitia Mottet, Corentin Prigent, Wissam Bouymedj, Yves Coudière, Gengis Lourenco, Xavier Muller.

CEMPACK

CEMPACK is a collection of software that was previously archived in different places. It includes the high-performance simulation code Propag and a suite of software to create geometric models, prepare inputs for Propag, and analyse its outputs. In 2017 the code was collected in an archive on Inria's GitLab platform. The main components of CEMPACK are the following.

• Propag-5.1

  Applied modeling studies performed by the Carmen team in collaboration with IHU Liryc and foreign partners 857, 45, 44, 42 rely on high-performance computations on the national supercomputers Irene, Zay, and Adastra. The Propag-5 code is optimized for these systems. It is the result of a decades-long development first at the Université de Montréal in Canada, then at Maastricht University in the Netherlands, and finally at the Institute of Computational Science of the Università della Svizzera italiana in Lugano, Switzerland. Since 2016 most of the development on Propag has been done by M. Potse at the Carmen team 59. The code scales excellently to large core counts 58 and, as it is controlled completely with command-line flags and configuration files, it can be used by non-programmers. It also features:

  • a plugin system for membrane models,
  • a completely parallel workflow, including the initial anatomy input and mesh partitioning, which allows it to work with meshes of more than ${10}^9$ nodes,
  • a flexible output scheme allowing hundreds of different state variables and transient variables to be output to file, when desired, using any spatial and temporal subsampling,
  • a configurable, LUSTRE-aware parallel output system in which groups of processes write HDF5/netCDF files, and
  • CWEB documentation of the entire code base.

  The code has been stable and reliable for many years. It can be considered the workhorse for our HPC work until CEPS takes over.

• Gepetto
  The Gepetto suite transforms a surface mesh of the heart into a set of (semi-)structured meshes for use by the Propag software or others. It creates the different fiber orientations in the model, including the transmurally rotating ventricular fibers and the various bundle structures in the atria (figure 2), and creates layers with possibly different electrophysiological properties across the wall. A practically important function is that it automatically builds the matching heart and torso meshes that Propag uses to simulate potentials in the torso (at a resolution of 1 mm) after projecting simulation results from the heart model (at 0.1 to 0.2 mm) on the coarser torso mesh 55. Like Propag, the Gepetto software results from a long-term development that started in Montreal, Canada, around 2002. The code for atrial fiber structure was developed by our team.
• Blender plugins
  Blender is a free software package for the production of 3-D models, renderings, and animations, comparable to commercial software such as Cinema4D. CEMPACK includes a set of plugins for Blender that facilitate the production of anatomical models and the visualization of measured and simulated data. It uses the MMG remeshing library, which is developed by the CARDAMOM team at Inria Bordeaux. Currently our segmentation work is mostly done with the MUSICardio software, but we still use Blender for finishing touches and high-quality visualization.

A 

B 

C 

An image of a torso model including the heart, the ribs, the lungs, the livers, and the location of torso electrodes, and a detailed image of an atrial anatomical model including fiber directions.

8.1 Analysis of partial differential equations

• Analysis of an extended bidomain model New results from the PhD thesis of Valentin Pannetier (still under embargo) en 2024 include the proof of the existence of solutions to the complete 3D model of pacemakers coupled to bidomain-with-bath equations, which was presented at CANUM 21, see also below about modeling.
• Analysis of a 1D/3D coupled problem in cardiac electrophysiology modeling In this work we analyze a coupled problem that describes the coupling two systems of reaction diffusion equation one on a three-dimensional domain representing the heart myocardium and the other on a one-dimensional tree representing the Purkinje network. Each system of PDEs is itself coupled to ordinary differential equations that describe the electrical activity at the cellular level. We establish the existence of a unique solution, utilizing a fixed-point approach with a judicious and non-conventional choice of functional spaces and contraction. 11

8.2 Numerical analysis and development of numerical methods

• Immersed boundary method for EIT In collaboration with Jérémi Dardé (IMT, Toulouse) and Niami Nasr (St Etienne) we studied the convergence of the gradient of the immersed boundary method for EIT that we previously developed during Niami Nasr's PhD thesis 51.
• Very high order finite volume methods In collaboration with R. Turpault and K. Khadra, Yves Coudière kept developing a very high order discretization method for the cardiac monodomain equations that scales well when executed in parallel.
• convergence analysisZeina Chehade analyzed numerically the convergence rate of the error for the discretization of the cardiac EMI model with the finite volume method that was developed earlier. She presented her results at the Eccomas conference in Lisbon (Portugal) 14 and at the Canum 19. This work is part of the MICROCARD project.
• Mechanisms underlying geometrical features of isochrons These tools allow us to study a highly-detailed depiction of the phase response of an oscillating cell in response to a stimulus, as a function of the stimulus properties. The results relate to the ongoing study of the Hodgkin-Huxley model with Profs Bernd Krauskopf and Hinke Osinga, where we had hypothesized a mechnism that gives rise to a distinct formation of isochrons. Following discussions with Kyoung Lee from University of Auckland in July, this hypothesis has been strengthened via his related observations in the planar FHN model. From this exchange, a clear mechanism was identified and has now been generalized to high-dimensional settings. Furthermore, a new structural feature has been uncovered, which, through geometrical and topological reasoning, we have shown is a necessary feature of all models.
• Locking rhythms of coupled phase oscillators In a theoretical study with Profs Leon Glass and Bard Ermentrout into the dynamics of generic coupled oscillators where a forcing oscillator drives a forced oscillator, we showed how certain rhythms are not possible for particular forms of coupling. Specifically, that the forced cycle must undergo at least one cycle for each cycle of the forcing, which is a phenomenon that has roles to play in biology such as cell division. These results are documented in a manuscript that is currently under review.

8.3 Modeling and inverse problems

• Modeling pacemakers Within the H2020 SimCardioTest European project, Valentin Pannetier defended his PhD thesis on Dec 6th 2024. In addition to the theoretical proof (see above) concerning the 3D model, the 0D model that was proposed the previous year was reworked for modeling accuracy. We presented a global sensitivity analysis of this model at CinC 2024 17. We pursued our efforts of software quality assurance within the V&V40 framework 36, presented at VPH 2024, by including in CEPS a benchmark for cardiac problems that was approved by the FDA 52. Finally, the 0D model was used as a testbench to demonstrate that it is possible to design a trial on new pacemaker, and run it entirely in-silico, as was explained in 15.

  

  Repartition of current going thrhough the tip electrode of a pacemaker, which directly impacts the possibility of capture. Capture is effective when the current magnitude exceeds a given threshold. More surface of electrode within the tissue does not necessarily lead to more chances of activation. The image shows that the intensity of the current is larger when the electrode is inserted at 40% of the tissue, compared to 60 and 80% insertions.

• A model for cardiac electroporation In the Dielectric project in collaboration with Inria Team MONC and IHU Liryc, Simon Bihoreau presented at CANUM 2024 30 and World Congress of Electroporation 2024 29 the first numerical results of the model we derived in 2023.
• Modeling the noise in EIT measurements During the internship of Sylvain Fourcade , in collaboration with Bénédicte Puig (LMAP, Pau), we developed a new formalism to study the inverse problem of EIT, based on the complete electrode model for EIT and the use of a Kohn-Vogelius functional to minimize, associated to the use of noise models to account for multiple measurements on the electrodes.
• A new source model for cardiac ECG imagingEmma Lagracie , Yves Coudière and Lisl Weynans , in collaboration with Yves Bourgault (Ottawa) proposed a new methodology for reconstructing activation maps from torso surface data, which incorporates information from the myocardial volume, while solving a surface problem on the heart. They formulated a 2D static forward model, derived from the bidomain model, by averaging equations in the heart. The averaged equations are coupled with the usual Laplace equations in the surrounding domains. For solving the inverse problem, this depth-averaged forward model is used as a constraint in an optimal control problem that allows to recover depth-averaged transmembrane voltage and extracellular potential in the heart, corresponding to observations on the body surface 12. This model was later extended to the epicardial surface in 3D (Epicardial Model), and used to study the effects of anisotropic conductivities in the source model on inverse problem reconstructions.
• Post processing methods for cardiac ECG imagingEmma Lagracie , Yves Coudière and Lisl Weynans compared several post-processing methods for computing activation maps from inverse ECGi reconstructions  16. In particular, using the Epicardial Model, they studied a Threshold Method on the transmembrane voltage, and showed that it tended to produce smooth maps, while the usual derivative-based methods produce artificial discontinuities.

8.4 Clinical applications

• Ananth Venkatesh was hired to work as part of a masters project on the ATLAS-RVA project together with Masimba Nemaire, in order to explore the annotation of cardiac signals via frequency decompositon. By combining these investigations with Ananth's prior experience with self-assisted learning, we were able to develop an annotation tool that can reliably detect the T-waves in both unipolar and ECG signals. The tool is adapted specifically to CARTO signals, requiring no prior processing, and achieves an accuracy beyond the current state-of-the-art. The general foundations of the method make it adaptable to different annotation problems and to different types of signal. A draft article presenting these results is currently in production.
• As part of the MICROCARD project, Joshua Steyer worked on how the cell-by-cell model can improve our understanding of cardiac electrograms, in particular in presence of a heterogeneous tissue 18, 34
• 27Narimane Gassa defended her PhD thesis in 2024. She presented her results on ???

8.5 High performance computing and Microscopic models

• More than a year of work of Corentin Prigent and Algiane Froehly (SED) has resulted in a robustification of the mmg3d code that made it able to remesh the fiercely complex meshes of cardiac tissue generated by the MICROCARD project. This was a crucial step towards simulations with geometrically realistic cell-by-cell models of cardiac tissue. The improvements have been included in version 5.8.0 of Mmgtools, released in November 2024, and are expected so serve anyone dealing with numerous, tightly separated internal boundaries in volumetric meshes. This was notably discussed at the final project workshop, which took place as a satellite of the Cardiac Physiome workshop 31

  

  Small piece (0.4mm length) of a cardiac tissue model, produced by the MICROCARD project and remeshed with mmg3d. The figure illustrates the numerous internal boundaries in this volumetric mesh, and the small angles under which they meet. The ability to remesh under these conditions is a major breakthrough for the project.

9.1 Bilateral Grants with Industry

• RebrAIn and Inria contracted an agreement allowing Nejib Zemzemi to pass 90 % of his time working at RebrAIn. The startup RebrAIn has been co-founded by N. Zemzemi and E. Cuny.
• Lisl Weynans obtained a grant from Fondation EDF to fund a research project about Electrical Impedance Tomography.

10.1 International initiatives

10.2 International research visitors

10.3 European initiatives

10.4 National initiatives

10.5 Regional initiatives

10.6 Other national collaborations

11.1 Promoting scientific activities

11.2 Teaching - Supervision - Juries

11.3 Popularization

12.1 Major publications

• 1 articleB.Boris Andreianov, M.Mostafa Bendahmane, K. H.Kenneth H. Karlsen and C.Charles Pierre. Convergence of discrete duality finite volume schemes for the cardiac bidomain model.Networks and Heterogeneous Media622011, 195-240HALback to text
• 2 articleA.Adnane Azzouzi, Y.Yves Coudière, R.Rodolphe Turpault and N.Nejib Zemzemi. A mathematical model of Purkinje-Muscle Junctions.Mathematical Biosciences and Engineering842011, 915-930
• 3 articleY.Yves Bourgault, Y.Yves Coudière and C.Charles Pierre. Existence And Uniqueness Of The Solution For The Bidomain Model Used In Cardiac Electrophysiology.Nonlinear Anal. Real World Appl.1012009, 458-482URL: http://hal.archives-ouvertes.fr/hal-00101458/fr
• 4 articleY.Yves Coudière, C.Charles Pierre, O.Olivier Rousseau and R.Rodolphe Turpault. A 2D/3D Discrete Duality Finite Volume Scheme. Application to ECG simulation.International Journal on Finite Volumes612009, URL: http://hal.archives-ouvertes.fr/hal-00328251/frback to text
• 5 articleY.Yves Coudière and C.Charles Pierre. Stability And Convergence Of A Finite Volume Method For Two Systems Of Reaction-Diffusion Equations In Electro-Cardiology.Nonlinear Anal. Real World Appl.742006, 916--935URL: http://hal.archives-ouvertes.fr/hal-00016816/frback to text
• 6 articleJ.Julien Engelhardt, E.Emmanuel Cuny, D.Dominique Guehl, P.Pierre Burbaud, N.Nathalie Damon-Perrière, C.Camille Dallies-Labourdette, J.Juliette Thomas, O.Olivier Branchard, L.-A.Louise-Amélie Schmitt, N.Narimane Gassa and N.Nejib Zemzemi. Prediction of Clinical Deep Brain Stimulation Target for Essential Tremor From 1.5 Tesla MRI Anatomical Landmarks.Frontiers in Neurology12October 2021HALDOIback to text
• 7 articleP. W.Peter W. Macfarlane, C.Charles Antzelevitch, M.Michel Haïssaguerre, H. V.Heikki V. Huikuri, M.Mark Potse, R.Raphael Rosso, F.Frederic Sacher, J. T.Jani T. Tikkanen, H.Hein Wellens and G.-X.Gan-Xin Yan. The Early Repolarization Pattern; A Consensus Paper.Journal of the American College of Cardiology66resulting from the Symposium on J Wave Patterns and a J Wave Syndrome, Glasgow, August 2013. Defines terminology for the J point: Jo, Jp, Jt. Provisionally accepted 19 May 2015.2015, 470-477URL: http://dx.doi.org/10.1016/j.jacc.2015.05.033back to text
• 8 articleV. M.Veronique M F Meijborg, M.Mark Potse, C. E.Chantal E Conrath, C. N.Charly N W Belterman, J. M.Jacques M T de Bakker and R.Ruben Coronel. Reduced Sodium Current in the Lateral Ventricular Wall Induces Inferolateral J-Waves.Front Physiol7365August 2016HALDOIback to textback to text
• 9 articleC.Charles Pierre. Preconditioning the bidomain model with almost linear complexity.Journal of Computational Physics2311January 2012, 82--97URL: http://www.sciencedirect.com/science/article/pii/S0021999111005122DOIback to text
• 10 articleJ.Job Stoks, P.Peter Langfield and M. J.Matthijs J.M. Cluitmans. Methodological and Mechanistic Considerations in Local Repolarization Mapping.JACC: Clinical Electrophysiology102February 2024, 376-377HALDOI

12.2 Publications of the year

12.3 Cited publications

• 35 inproceedingsA.Andony Arrieula, H.Hubert Cochet, P.Pierre Jaïs, M.Michel Haïssaguerre and M.Mark Potse. An Improved Iterative Pace-Mapping Algorithm to Detect the Origin of Premature Ventricular Contractions.Computing in Cardiology47abstract nr 62, really early. Oral presentation.RiminiComputing in Cardiology2020, 62HALDOIback to text
• 36 bookAssessing the credibility of computational modeling through verification and validation: Application to medical devices.2018back to text
• 37 inproceedingsP.-E.Pierre-Elliott Bécue, F.Florian Caro, M.Mostafa Bendahmane and M.Mark Potse. Modélisation et simulation de l'électrophysiologie cardiaque à l'échelle microscopique.43e Congrès National d'Analyse Numérique (CANUM)oral presentationSMAIObernai, Alsace, FranceMay 2016, URL: http://smai.emath.fr/canum2016/resumesPDF/peb/Abstract.pdfback to text
• 38 miscP.-E.Pierre-Elliott Bécue, F.Florian Caro, M.Mark Potse and Y.Yves Coudière. Theoretical and Numerical Study of Cardiac Electrophysiology Problems at the Microscopic Scale..PosterJuly 2016HALback to text
• 39 inproceedingsP.-E.Pierre-Elliott Bécue, M.Mark Potse and Y.Yves Coudière. A Three-Dimensional Computational Model of Action Potential Propagation Through a Network of Individual Cells.Computing in Cardiology 2017Rennes, FranceSeptember 2017, 1-4HALback to text
• 40 inproceedingsP.-E.Pierre-Elliott Bécue, M.Mark Potse and Y.Yves Coudière. Microscopic Simulation of the Cardiac Electrophysiology: A Study of the Influence of Different Gap Junctions Models.Computing in CardiologyMaastricht, NetherlandsSeptember 2018HALback to text
• 41 articleB.Benjamin Berte, F.Frederic Sacher, S.Saagar Mahida, S.Seigo Yamashita, H. S.Han S. Lim, A.Arnaud Denis, N.Nicolas Derval, M.Mélèze Hocini, M.Michel Haïssaguerre, H.Hubert Cochet and P.Pierre Jaïs. Impact of Septal Radiofrequency Ventricular Tachycardia Ablation; Insights From Magnetic Resonance Imaging.Circulation1302014, 716-718URL: https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.114.010175back to text
• 42 inproceedingsJ.Judit Chamorro Servent, L.Laura Bear, J.Josselin Duchateau, M.Mark Potse, R.Rémi Dubois and Y.Yves Coudière. Do we need to enforce the homogeneous Neuman condition on the Torso for solving the inverse electrocardiographic problem by using the method of fundamental solution ?Computing in Cardiology 201643Computing in Cardiology 2016Vancouver, CanadaSeptember 2016, 425-428HALback to text
• 43 articleY.Yves Coudière, Y.Yves Bourgault and M.Myriam Rioux. Optimal monodomain approximations of the bidomain equations used in cardiac electrophysiology.Mathematical Models and Methods in Applied Sciences246February 2014, 1115-1140HALback to textback to text
• 44 articleJ.Josselin Duchateau, M.Mark Potse and R.Remi Dubois. Spatially Coherent Activation Maps for Electrocardiographic Imaging.IEEE Transactions on Biomedical Engineering64May 2017, 1149-1156HALDOIback to text
• 45 inproceedingsA.Ali Gharaviri, M.Mark Potse, S.Sander Verheule, R.Rolf Krause, A.Angelo Auricchio and U.Ulrich Schotten. Epicardial Fibrosis Explains Increased Transmural Conduction in a Computer Model of Atrial Fibrillation .Computing in CardiologyVancouver, CanadaSeptember 2016HALback to textback to textback to text
• 46 articleM.Michel Haïssaguerre, N.N. Derval, F.F. Sacher, L.L. Jesel, I.I. Deisenhofer, L.L. de Roy, J. L.J. L. Pasquié, A.A. Nogami, D.D. Babuty, S.S. Yli-Mayry, C.C. De Chillou, P.P. Scanu, P.P. Mabo, S.S. Matsuo, V.V. Probst, S.S. Le Scouarnec, P.P. Defaye, J.J. Schlaepfer, T.T. Rostock, D.D. Lacroix, D.D. Lamaison, T.T. Lavergne, Y.Y. Aizawa, A.A. Englund, F.F. Anselme, M.M. O'Neill, M.M. Hocini, K. T.K. T. Lim, S.S. Knecht, G. D.G. D. Veenhuyzen, P.P. Bordachar, M.M. Chauvin, P.P. Jaïs, G.G. Coureau, G.G. Chene, G. J.G. J. Klein and J.J. Clémenty. Sudden cardiac arrest associated with early repolarization.N. Engl. J. Med.3582008, 2016--2023back to text
• 47 articleM.M. Haïssaguerre, P.P. Jaïs, D. C.D. C. Shah, S.S. Garrigue, A.A. Takahashi, T.T. Lavergne, M.M. Hocini, J. T.J. T. Peng, R.R. Roudaut and J.J Clémenty. Spontaneous initiation of atrial fibrillation by ectopic beats originating in the pulmonary veins.N. Engl. J. Med.3391998, 659-666URL: https://www.nejm.org/doi/full/10.1056/NEJM199809033391003back to text
• 48 articleM. G.Mark G. Hoogendijk, M.Mark Potse, A. C.André C. Linnenbank, A. O.Arie O. Verkerk, H. M.Hester M. den Ruijter, S. C.Shirley C. M. van Amersfoorth, E. C.Eva C. Klaver, L.Leander Beekman, C. R.Connie R. Bezzina, P. G.Pieter G. Postema, H. L.Hanno L. Tan, A. G.Annette G. Reimer, A. C.Allard C. van der Wal, A. D.Arend D. J. ten Harkel, M.Michiel Dalinghaus, A.Alain Vinet, A. A.Arthur A. M. Wilde, J. M.Jacques M. T. de Bakker and R.Ruben Coronel. Mechanism of Right Precordial ST-Segment Elevation in Structural Heart Disease: Excitation Failure by Current-to-Load Mismatch.Heart Rhythm72010, 238-248URL: http://dx.doi.org/10.1016/j.hrthm.2009.10.007back to text
• 49 articleM. L.Marjorie Letitia Hubbard and C. S.Craig S. Henriquez. A microstructural model of reentry arising from focal breakthrough at sites of source-load mismatch in a central region of slow conduction.Am. J. Physiol. Heart Circ. Physiol.3062014, H1341-1352back to text
• 50 inproceedingsM.Michal Kania, Y.Yves Coudière, H.Hubert Cochet, M.Michel Haissaguerre, P.Pierre Ja\"is and M.Mark Potse. A new ECG-based method to guide catheter ablation of ventricular tachycardia.iMAging and eLectrical TechnologiesUppsala, SwedenApril 2018HALback to text
• 51 phdthesisN.Niami Nasr. Méthodes numériques pour la tomographie par impédance électrique dans le cadre de l'électrocardiographie.Université de BordeauxDecember 2023HALback to text
• 52 articleP.Pras Pathmanathan and R. A.Richard A Gray. Verification of computational models of cardiac electro-physiology.Int. J. Numer. Method. Biomed. Eng.305May 2014, 525--544back to textback to text
• 53 inproceedingsM.Mark Potse, L.Luca Cirrottola and A.Algiane Froehly. A practical algorithm to build geometric models of cardiac muscle structure.ECCOMAS 2022 - The 8th European Congress on Computational Methods in Applied Sciences and EngineeringOslo, NorwayJune 2022HALback to text
• 54 articleM.Mark Potse, B.Bruno Dubé, J.Jacques Richer, A.Alain Vinet and R. M.Ramesh M. Gulrajani. A Comparison of monodomain and bidomain reaction-diffusion.IEEE Transactions on Biomedical Engineering53122006, 2425-2435URL: http://dx.doi.org/10.1109/TBME.2006.880875back to text
• 55 articleM.Mark Potse, B.Bruno Dubé and A.Alain Vinet. Cardiac Anisotropy in Boundary-Element Models for the Electrocardiogram.Medical and Biological Engineering and Computing472009, 719--729URL: http://dx.doi.org/10.1007/s11517-009-0472-xback to text
• 56 inproceedingsM.Mark Potse, A.Ali Gharaviri, S.Simone Pezzuto, A.Angelo Auricchio, R.Rolf Krause, S.Sander Verheule and U.Ulrich Schotten. Anatomically-induced Fibrillation in a 3D model of the Human Atria.Computing in CardiologyMaastricht, NetherlandsSeptember 2018HALback to text
• 57 miscM.Mark Potse, V. M.Veronique M F Meijborg, C. N.Charly N W Belterman, J. M.Jacques M T de Bakker, C. E.Chantal E Conrath and R.Ruben Coronel. Regional conduction slowing can explain inferolateral J waves and their attenuation by sodium channel blockers.PosterSeptember 2016HALback to text
• 58 inproceedingsM.Mark Potse, E.Emmanuelle Saillard, D.Denis Barthou and Y.Yves Coudière. Feasibility of Whole-Heart Electrophysiological Models With Near-Cellular Resolution.CinC 2020 - Computing in CardiologyRimini / Virtual, ItalySeptember 2020HALDOIback to text
• 59 articleM.Mark Potse. Scalable and Accurate ECG Simulation for Reaction-Diffusion Models of the Human Heart.Frontiers in Physiology9April 2018, 370HALDOIback to text
• 60 articleA.Aslak Tveito, K. H.Karoline H. J\ae}ger, M.Miroslav Kuchta, K.-A.Kent-Andre Mardal and M. E.Marie E. Rognes. A Cell-Based Framework for Numerical Modeling of Electrical Conduction in Cardiac Tissue.Front. Phys.5This is very very similar to what we were doing with PEB... Looks like we're scooped at least for the approach, but we do have a few abstracts ([becue:cinc17], [becue16a], MMCE meeting in Ottawa November 2017). Note it's in Frontiers in (Biomedical) Physics, not Physiology.2017, 48back to textback to text