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Biasi N, Seghetti P, Tognetti A. Diffuse fibrosis and repolarization disorders explain ventricular arrhythmias in Brugada syndrome: a computational study. Sci Rep 2022; 12:8530. [PMID: 35595775 PMCID: PMC9123016 DOI: 10.1038/s41598-022-12239-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 05/06/2022] [Indexed: 11/20/2022] Open
Abstract
In this work, we reported a computational study to quantitatively determine the individual contributions of three candidate arrhythmic factors associated with Brugada Syndrome. In particular, we focused our analysis on the role of structural abnormalities, dispersion of repolarization, and size of the diseased region. We developed a human phenomenological model capable of replicating the action potential characteristics both in Brugada Syndrome and in healthy conditions. Inspired by physiological observations, we employed the phenomenological model in a 2D geometry resembling the pathological RVOT coupled with healthy epicardial tissue. We assessed the insurgence of sustained reentry as a function of electrophysiological and structural abnormalities. Our computational study indicates that both structural and repolarization abnormalities are essential to induce sustained reentry. Furthermore, our results suggest that neither dispersion of repolarization nor structural abnormalities are sufficient on their own to induce sustained reentry. It should be noted how our study seems to explain an arrhythmic mechanism that unifies the classic repolarization and depolarization hypotheses of the pathophysiology of the Brugada Syndrome. Finally, we believe that this work may offer a new perspective on the computational and clinical investigation of Brugada Syndrome and its arrhythmic behaviour.
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Affiliation(s)
- Niccoló Biasi
- Department of Information Engineering, University of Pisa, Pisa, Italy.
| | - Paolo Seghetti
- Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.,National Research Council, Institute of Clinical Physiology, Pisa, Italy
| | - Alessandro Tognetti
- Department of Information Engineering, University of Pisa, Pisa, Italy.,Research Centre "E. Piaggio", University of Pisa, Pisa, Italy
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2
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Biasi N, Tognetti A. A computationally efficient dynamic model of human epicardial tissue. PLoS One 2021; 16:e0259066. [PMID: 34699557 PMCID: PMC8547700 DOI: 10.1371/journal.pone.0259066] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 10/11/2021] [Indexed: 11/29/2022] Open
Abstract
We present a new phenomenological model of human ventricular epicardial cells and we test its reentry dynamics. The model is derived from the Rogers-McCulloch formulation of the FitzHugh-Nagumo equations and represents the total ionic current divided into three contributions corresponding to the excitatory, recovery and transient outward currents. Our model reproduces the main characteristics of human epicardial tissue, including action potential amplitude and morphology, upstroke velocity, and action potential duration and conduction velocity restitution curves. The reentry dynamics is stable, and the dominant period is about 270 ms, which is comparable to clinical values. The proposed model is the first phenomenological model able to accurately resemble human experimental data by using only 3 state variables and 17 parameters. Indeed, it is more computationally efficient than existing models (i.e., almost two times faster than the minimal ventricular model). Beyond the computational efficiency, the low number of parameters facilitates the process of fitting the model to the experimental data.
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Affiliation(s)
- Niccoló Biasi
- Department of Information Engineering, University of Pisa, Pisa, Italy
| | - Alessandro Tognetti
- Department of Information Engineering, University of Pisa, Pisa, Italy.,Research Centre "E. Piaggio", University of Pisa, Pisa, Italy
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3
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Bragard J, Witt A, Laroze D, Hawks C, Elorza J, Rodríguez Cantalapiedra I, Peñaranda A, Echebarria B. Conductance heterogeneities induced by multistability in the dynamics of coupled cardiac gap junctions. CHAOS (WOODBURY, N.Y.) 2021; 31:073144. [PMID: 34340360 DOI: 10.1063/5.0053651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
In this paper, we study the propagation of the cardiac action potential in a one-dimensional fiber, where cells are electrically coupled through gap junctions (GJs). We consider gap junctional gate dynamics that depend on the intercellular potential. We find that different GJs in the tissue can end up in two different states: a low conducting state and a high conducting state. We first present evidence of the dynamical multistability that occurs by setting specific parameters of the GJ dynamics. Subsequently, we explain how the multistability is a direct consequence of the GJ stability problem by reducing the dynamical system's dimensions. The conductance dispersion usually occurs on a large time scale, i.e., thousands of heartbeats. The full cardiac model simulations are computationally demanding, and we derive a simplified model that allows for a reduction in the computational cost of four orders of magnitude. This simplified model reproduces nearly quantitatively the results provided by the original full model. We explain the discrepancies between the two models due to the simplified model's lack of spatial correlations. This simplified model provides a valuable tool to explore cardiac dynamics over very long time scales. That is highly relevant in studying diseases that develop on a large time scale compared to the basic heartbeat. As in the brain, plasticity and tissue remodeling are crucial parameters in determining the action potential wave propagation's stability.
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Affiliation(s)
- J Bragard
- Departamento de Física y Matemática Aplicada, Universidad de Navarra, Pamplona 31080, Spain
| | - A Witt
- Max-Planck Institute, Gottingen 37077, Germany
| | - D Laroze
- Instituto de Alta Investigación, CEDENNA, Universidad de Tarapacá, Casilla 7D, Arica, Chile
| | - C Hawks
- Departamento de Física y Matemática Aplicada, Universidad de Navarra, Pamplona 31080, Spain
| | - J Elorza
- Departamento de Física y Matemática Aplicada, Universidad de Navarra, Pamplona 31080, Spain
| | | | - A Peñaranda
- Departament de Física, Universitat Politècnica de Catalunya, Barcelona 08068, Spain
| | - B Echebarria
- Departament de Física, Universitat Politècnica de Catalunya, Barcelona 08068, Spain
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4
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Kistamás K, Veress R, Horváth B, Bányász T, Nánási PP, Eisner DA. Calcium Handling Defects and Cardiac Arrhythmia Syndromes. Front Pharmacol 2020; 11:72. [PMID: 32161540 PMCID: PMC7052815 DOI: 10.3389/fphar.2020.00072] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 01/24/2020] [Indexed: 12/13/2022] Open
Abstract
Calcium ions (Ca2+) play a major role in the cardiac excitation-contraction coupling. Intracellular Ca2+ concentration increases during systole and falls in diastole thereby determining cardiac contraction and relaxation. Normal cardiac function also requires perfect organization of the ion currents at the cellular level to drive action potentials and to maintain action potential propagation and electrical homogeneity at the tissue level. Any imbalance in Ca2+ homeostasis of a cardiac myocyte can lead to electrical disturbances. This review aims to discuss cardiac physiology and pathophysiology from the elementary membrane processes that can cause the electrical instability of the ventricular myocytes through intracellular Ca2+ handling maladies to inherited and acquired arrhythmias. Finally, the paper will discuss the current therapeutic approaches targeting cardiac arrhythmias.
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Affiliation(s)
- Kornél Kistamás
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Division of Cardiovascular Sciences, School of Medical Sciences, University of Manchester, Manchester, United Kingdom
| | - Roland Veress
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamás Bányász
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Department of Dental Physiology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - David A Eisner
- Division of Cardiovascular Sciences, School of Medical Sciences, University of Manchester, Manchester, United Kingdom
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5
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Hazim A, Belhamadia Y, Dubljevic S. Effects of mechano-electrical feedback on the onset of alternans: A computational study. CHAOS (WOODBURY, N.Y.) 2019; 29:063126. [PMID: 31266317 DOI: 10.1063/1.5095778] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
Cardiac alternans is a heart rhythm instability that is associated with cardiac arrhythmias and may lead to sudden cardiac death. The onset of this instability, which is linked to period-doubling bifurcation and may be a route to chaos, is of particular interest. Mechano-electric feedback depicts the effects of tissue deformation on cardiac excitation. The main effect of mechano-electric feedback is delivered via the so-called stretch-activated ion channels and is caused by stretch-activated currents. Mechano-electric feedback, which is believed to have proarrhythmic and antiarrhythmic effects on cardiac electrophysiology, affects the action potential duration in a manner dependent on cycle length, but the mechanisms by which this occurs remain to be elucidated. In this study, a biophysically detailed electromechanical model of cardiac tissue is employed to show how a stretch-activated current can affect the action potential duration at cellular and tissue levels, illustrating its effects on the onset of alternans. Also, using a two-dimensional iterated map that incorporates stretch-activated current effects, we apply linear stability analysis to study the stability of the bifurcation. We show that alternans bifurcation can be prevented depending on the strength of the stretch-activated current.
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Affiliation(s)
- Azzam Hazim
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta T6G 2V2, Canada
| | - Youssef Belhamadia
- Department of Mathematics and Statistics, American University of Sharjah, Sharjah, United Arab Emirates
| | - Stevan Dubljevic
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada
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6
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An African loss-of-function CACNA1C variant p.T1787M associated with a risk of ventricular fibrillation. Sci Rep 2018; 8:14619. [PMID: 30279520 PMCID: PMC6168548 DOI: 10.1038/s41598-018-32867-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 09/17/2018] [Indexed: 12/13/2022] Open
Abstract
Calcium regulation plays a central role in cardiac function. Several variants in the calcium channel Cav1.2 have been implicated in arrhythmic syndromes. We screened patients with Brugada syndrome, short QT syndrome, early repolarisation syndrome, and idiopathic ventricular fibrillation to determine the frequency and pathogenicity of Cav1.2 variants. Cav1.2 related genes, CACNA1C, CACNB2 and CACNA2D1, were screened in 65 probands. Missense variants were introduced in the Cav1.2 alpha subunit plasmid by mutagenesis to assess their pathogenicity using patch clamp approaches. Six missense variants were identified in CACNA1C in five individuals. Five of them, A1648T, A1689T, G1795R, R1973Q, C1992F, showed no major alterations of the channel function. The sixth C-terminal variant, Cavα1c-T1787M, present mostly in the African population, was identified in two patients with resuscitated cardiac arrest. The first patient originated from Cameroon and the second was an inhabitant of La Reunion Island with idiopathic ventricular fibrillation originating from Purkinje tissues. Patch-clamp analysis revealed that Cavα1c-T1787M reduces the calcium and barium currents by increasing the auto-inhibition mediated by the C-terminal part and increases the voltage-dependent inhibition. We identified a loss-of-function variant, Cavα1c-T1787M, present in 0.8% of the African population, as a new risk factor for ventricular arrhythmia.
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Cheniti G, Vlachos K, Meo M, Puyo S, Thompson N, Denis A, Duchateau J, Takigawa M, Martin C, Frontera A, Kitamura T, Lam A, Bourier F, Klotz N, Derval N, Sacher F, Jais P, Dubois R, Hocini M, Haissaguerre M. Mapping and Ablation of Idiopathic Ventricular Fibrillation. Front Cardiovasc Med 2018; 5:123. [PMID: 30280100 PMCID: PMC6153961 DOI: 10.3389/fcvm.2018.00123] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 08/20/2018] [Indexed: 01/30/2023] Open
Abstract
Idiopathic ventricular fibrillation (IVF) is the main cause of unexplained sudden cardiac death, particularly in young patients under the age of 35. IVF is a diagnosis of exclusion in patients who have survived a VF episode without any identifiable structural or metabolic causes despite extensive diagnostic testing. Genetic testing allows identification of a likely causative mutation in up to 27% of unexplained sudden deaths in children and young adults. In the majority of cases, VF is triggered by PVCs that originate from the Purkinje network. Ablation of VF triggers in this setting is associated with high rates of acute success and long-term freedom from VF recurrence. Recent studies demonstrate that a significant subset of IVF defined by negative comprehensive investigations, demonstrate in fact subclinical structural alterations. These localized myocardial alterations are identified by high density electrogram mapping, are of small size and are mainly located in the epicardium. As reentrant VF drivers are often colocated with regions of abnormal electrograms, this localized substrate can be shown to be mechanistically linked with VF. Such areas may represent an important target for ablation.
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Affiliation(s)
- Ghassen Cheniti
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France.,Department of Cardiology, Sahloul Hospital, Universite de Sousse, Sousse, Tunisia
| | - Konstantinos Vlachos
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Marianna Meo
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Stephane Puyo
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Nathaniel Thompson
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Arnaud Denis
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Josselin Duchateau
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Masateru Takigawa
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Claire Martin
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France.,Department of Cardiology, Royal Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - Antonio Frontera
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Takeshi Kitamura
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Anna Lam
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Felix Bourier
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Nicolas Klotz
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Nicolas Derval
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Frederic Sacher
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Pierre Jais
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Remi Dubois
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Meleze Hocini
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Michel Haissaguerre
- Electrophysiology and Ablation Unit, Bordeaux University Hospital (CHU), Pessac, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
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9
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Alonso S, Bär M, Echebarria B. Nonlinear physics of electrical wave propagation in the heart: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:096601. [PMID: 27517161 DOI: 10.1088/0034-4885/79/9/096601] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The beating of the heart is a synchronized contraction of muscle cells (myocytes) that is triggered by a periodic sequence of electrical waves (action potentials) originating in the sino-atrial node and propagating over the atria and the ventricles. Cardiac arrhythmias like atrial and ventricular fibrillation (AF,VF) or ventricular tachycardia (VT) are caused by disruptions and instabilities of these electrical excitations, that lead to the emergence of rotating waves (VT) and turbulent wave patterns (AF,VF). Numerous simulation and experimental studies during the last 20 years have addressed these topics. In this review we focus on the nonlinear dynamics of wave propagation in the heart with an emphasis on the theory of pulses, spirals and scroll waves and their instabilities in excitable media with applications to cardiac modeling. After an introduction into electrophysiological models for action potential propagation, the modeling and analysis of spatiotemporal alternans, spiral and scroll meandering, spiral breakup and scroll wave instabilities like negative line tension and sproing are reviewed in depth and discussed with emphasis on their impact for cardiac arrhythmias.
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Affiliation(s)
- Sergio Alonso
- Physikalisch-Technische Bundesanstalt, Abbestr. 2-12 10587, Berlin, Germany. Department of Physics, Universitat Politècnica de Catalunya, Av. Dr. Marañón 44, E-08028 Barcelona, Spain
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10
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Maoz A, Christini DJ, Krogh-Madsen T. Dependence of phase-2 reentry and repolarization dispersion on epicardial and transmural ionic heterogeneity: a simulation study. Europace 2014; 16:458-65. [PMID: 24569901 DOI: 10.1093/europace/eut379] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
AIMS Phase-2 reentry (P2R) is a local arrhythmogenic phenomenon where electrotonic current propagates from a spike-and-dome action potential region to re-excite a loss-of-dome action potential region. While ionic heterogeneity has been shown to underlie P2R within the epicardium and has been hypothesized to occur transmurally, we are unaware of any study that has investigated the effects of combining these heterogeneities as they occur in the heart. Thus, we tested the hypothesis that P2R can result by either epicardial or transmural heterogeneity and that the realistic combination of the two would increase the likelihood of P2R. METHODS AND RESULTS We used computational ionic models of cardiac myocyte dynamics to investigate initiation and development of P2R in simulated tissues with different ionic heterogeneities. In one-dimensional transmural cable simulations, P2R occurred when the conductance of the transient outward current in the epicardial region was near the range for which epicardial action potentials switched intermittently between spike-and-dome and loss-of-dome morphologies. Phase-2 reentry was more likely in two-dimensional tissue simulations by both epicardial and transmural heterogeneity and could expand beyond its local initiation site to create a macroscopic reentry. CONCLUSION The characteristics and stability of action potential morphology in the epicardium are important determinants of the occurrence of both transmural and epicardial P2R and its associated arrhythmogenesis.
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Affiliation(s)
- Anat Maoz
- Greenberg Division of Cardiology, Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
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11
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Peñaranda A, Cantalapiedra IR, Bragard J, Echebarria B. Cardiac dynamics: a simplified model for action potential propagation. Theor Biol Med Model 2012; 9:50. [PMID: 23194429 PMCID: PMC3577582 DOI: 10.1186/1742-4682-9-50] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 11/19/2012] [Indexed: 11/10/2022] Open
Abstract
This paper analyzes a new semiphysiological ionic model, used recently to study reexitations and reentry in cardiac tissue [I.R. Cantalapiedra et al, PRE 82 011907 (2010)]. The aim of the model is to reproduce action potencial morphologies and restitution curves obtained, either from experimental data, or from more complex electrophysiological models. The model divides all ion currents into four groups according to their function, thus resulting into fast-slow and inward-outward currents. We show that this simplified model is flexible enough as to accurately capture the electrical properties of cardiac myocytes, having the advantage of being less computational demanding than detailed electrophysiological models. Under some conditions, it has been shown to be amenable to mathematical analysis. The model reproduces the action potential (AP) change with stimulation rate observed both experimentally and in realistic models of healthy human and guinea pig myocytes (TNNP and LRd models, respectively). When simulated in a cable it also gives the right dependence of the conduction velocity (CV) with stimulation rate. Besides reproducing correctly these restitution properties, it also gives a good fit for the morphology of the AP, including the notch typical of phase 1. Finally, we perform simulations in a realistic geometric model of the rabbit's ventricles, finding a good qualitative agreement in AP propagation and the ECG. Thus, this simplified model represents an alternative to more complex models when studying instabilities in wave propagation.
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Affiliation(s)
- Angelina Peñaranda
- Departament de Física Aplicada, Universitat Politècnica de Catalunya. BarcelonaTech, Av. Dr. Marañon 44-50, 08028 Barcelona, Spain
| | - Inma R Cantalapiedra
- Departament de Física Aplicada, Universitat Politècnica de Catalunya. BarcelonaTech, Av. Dr. Marañon 44-50, 08028 Barcelona, Spain
| | - Jean Bragard
- Departamento de Física y Matemática Aplicada, Universidad de Navarra, Irunlarrea s/n, 31080 Pamplona, Spain
| | - Blas Echebarria
- Departament de Física Aplicada, Universitat Politècnica de Catalunya. BarcelonaTech, Av. Dr. Marañon 44-50, 08028 Barcelona, Spain
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