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Camps J, Berg LA, Wang ZJ, Sebastian R, Riebel LL, Doste R, Zhou X, Sachetto R, Coleman J, Lawson B, Grau V, Burrage K, Bueno-Orovio A, Weber Dos Santos R, Rodriguez B. Digital twinning of the human ventricular activation sequence to Clinical 12-lead ECGs and magnetic resonance imaging using realistic Purkinje networks for in silico clinical trials. Med Image Anal 2024; 94:103108. [PMID: 38447244 DOI: 10.1016/j.media.2024.103108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 02/06/2024] [Accepted: 02/13/2024] [Indexed: 03/08/2024]
Abstract
Cardiac in silico clinical trials can virtually assess the safety and efficacy of therapies using human-based modelling and simulation. These technologies can provide mechanistic explanations for clinically observed pathological behaviour. Designing virtual cohorts for in silico trials requires exploiting clinical data to capture the physiological variability in the human population. The clinical characterisation of ventricular activation and the Purkinje network is challenging, especially non-invasively. Our study aims to present a novel digital twinning pipeline that can efficiently generate and integrate Purkinje networks into human multiscale biventricular models based on subject-specific clinical 12-lead electrocardiogram and magnetic resonance recordings. Essential novel features of the pipeline are the human-based Purkinje network generation method, personalisation considering ECG R wave progression as well as QRS morphology, and translation from reduced-order Eikonal models to equivalent biophysically-detailed monodomain ones. We demonstrate ECG simulations in line with clinical data with clinical image-based multiscale models with Purkinje in four control subjects and two hypertrophic cardiomyopathy patients (simulated and clinical QRS complexes with Pearson's correlation coefficients > 0.7). Our methods also considered possible differences in the density of Purkinje myocardial junctions in the Eikonal-based inference as regional conduction velocities. These differences translated into regional coupling effects between Purkinje and myocardial models in the monodomain formulation. In summary, we demonstrate a digital twin pipeline enabling simulations yielding clinically consistent ECGs with clinical CMR image-based biventricular multiscale models, including personalised Purkinje in healthy and cardiac disease conditions.
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Affiliation(s)
- Julia Camps
- University of Oxford, Oxford, United Kingdom.
| | | | | | | | | | - Ruben Doste
- University of Oxford, Oxford, United Kingdom
| | - Xin Zhou
- University of Oxford, Oxford, United Kingdom
| | - Rafael Sachetto
- Universidade Federal de São João del Rei, São João del Rei, MG, Brazil
| | | | - Brodie Lawson
- Queensland University of Technology, Brisbane, Australia
| | | | - Kevin Burrage
- University of Oxford, Oxford, United Kingdom; Queensland University of Technology, Brisbane, Australia
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Coleman JA, Doste R, Ashkir Z, Coppini R, Sachetto R, Watkins H, Raman B, Bueno-Orovio A. Mechanisms of ischaemia-induced arrhythmias in hypertrophic cardiomyopathy: a large-scale computational study. Cardiovasc Res 2024:cvae086. [PMID: 38646743 DOI: 10.1093/cvr/cvae086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/31/2024] [Accepted: 03/17/2024] [Indexed: 04/23/2024] Open
Abstract
AIMS Lethal arrhythmias in hypertrophic cardiomyopathy (HCM) are widely attributed to myocardial ischaemia and fibrosis. How these factors modulate arrhythmic risk remains largely unknown, especially as invasive mapping protocols are not routinely used in these patients. By leveraging multiscale digital-twin technologies, we aim to investigate ischaemic mechanisms of increased arrhythmic risk in HCM. METHODS AND RESULTS Computational models of human HCM cardiomyocytes, tissue and ventricles were used to simulate outcomes of phase 1A acute myocardial ischaemia. Cellular response predictions were validated with patch-clamp studies of human HCM cardiomyocytes (n=12 cells, N=5 patients). Ventricular simulations were informed by typical distributions of subendocardial/transmural ischaemia as analysed in perfusion scans (N=28 patients). S1-S2 pacing protocols were used to quantify arrhythmic risk for scenarios in which regions of septal obstructive hypertrophy were affected by (i) ischaemia, (ii) ischaemia and impaired repolarisation, and (iii) ischaemia, impaired repolarisation, and diffuse fibrosis.HCM cardiomyocytes exhibited enhanced action potential and abnormal effective refractory period shortening to ischaemic insults. Analysis of c.a. 75,000 re-entry induction cases revealed that the abnormal HCM cellular response enabled establishment of arrhythmia at milder ischaemia than otherwise possible in healthy myocardium, due to larger refractoriness gradients that promoted conduction block. Arrhythmias were more easily sustained in transmural than subendocardial ischaemia. Mechanisms of ischaemia-fibrosis interaction were strongly electrophysiology dependent. Fibrosis enabled asymmetric re-entry patterns and break-up into sustained ventricular tachycardia. CONCLUSIONS HCM ventricles exhibited an increased risk to non-sustained and sustained re-entry, largely dominated by an impaired cellular response and deleterious interactions with the diffuse fibrotic substrate.
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Affiliation(s)
- James A Coleman
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Ruben Doste
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Zakariye Ashkir
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
| | - Raffaele Coppini
- Department of NeuroFarBa, University of Florence, Florence, Italy
| | - Rafael Sachetto
- Department of Computer Science, Federal University of São João del-Rei, Minas Gerais, Brazil
| | - Hugh Watkins
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
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Corral Acero J, Lamata P, Eitel I, Zacur E, Evertz R, Lange T, Backhaus SJ, Stiermaier T, Thiele H, Bueno-Orovio A, Schuster A, Grau V. Comprehensive characterization of cardiac contraction for improved post-infarction risk assessment. Sci Rep 2024; 14:8951. [PMID: 38637609 PMCID: PMC11026383 DOI: 10.1038/s41598-024-59114-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 04/08/2024] [Indexed: 04/20/2024] Open
Abstract
This study aims at identifying risk-related patterns of left ventricular contraction dynamics via novel volume transient characterization. A multicenter cohort of AMI survivors (n = 1021) who underwent Cardiac Magnetic Resonance (CMR) after infarction was considered for the study. The clinical endpoint was the 12-month rate of major adverse cardiac events (MACE, n = 73), consisting of all-cause death, reinfarction, and new congestive heart failure. Cardiac function was characterized from CMR in 3 potential directions: by (1) volume temporal transients (i.e. contraction dynamics); (2) feature tracking strain analysis (i.e. bulk tissue peak contraction); and (3) 3D shape analysis (i.e. 3D contraction morphology). A fully automated pipeline was developed to extract conventional and novel artificial-intelligence-derived metrics of cardiac contraction, and their relationship with MACE was investigated. Any of the 3 proposed directions demonstrated its additional prognostic value on top of established CMR indexes, myocardial injury markers, basic characteristics, and cardiovascular risk factors (P < 0.001). The combination of these 3 directions of enhancement towards a final CMR risk model improved MACE prediction by 13% compared to clinical baseline (0.774 (0.771-0.777) vs. 0.683 (0.681-0.685) cross-validated AUC, P < 0.001). The study evidences the contribution of the novel contraction characterization, enabled by a fully automated pipeline, to post-infarction assessment.
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Affiliation(s)
- Jorge Corral Acero
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, UK.
| | - Pablo Lamata
- Department of Digital Twins for Healthcare, School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor North Wing, St Thomas' Hospital, London, SE1 7EH, UK.
| | - Ingo Eitel
- Medical Clinic II, Cardiology, Angiology and Intensive Care Medicine, University Heart Centre Lübeck, Lübeck, Germany
- University Hospital Schleswig-Holstein, Lübeck, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Ernesto Zacur
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, UK
| | - Ruben Evertz
- Department of Cardiology and Pneumology, University Medical Centre Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Lower Saxony, Göttingen, Germany
| | - Torben Lange
- Department of Cardiology and Pneumology, University Medical Centre Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Lower Saxony, Göttingen, Germany
| | - Sören J Backhaus
- Department of Cardiology, Campus Kerckhoff of the Justus-Liebig-University Giessen, Kerckhoff-Clinic, Bad Nauheim, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Bad Nauheim, Germany
| | - Thomas Stiermaier
- Medical Clinic II, Cardiology, Angiology and Intensive Care Medicine, University Heart Centre Lübeck, Lübeck, Germany
- University Hospital Schleswig-Holstein, Lübeck, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Holger Thiele
- Department of Internal Medicine/Cardiology and Leipzig Heart Science, Heart Centre Leipzig at University of Leipzig, Leipzig, Germany
| | | | - Andreas Schuster
- Department of Cardiology and Pneumology, University Medical Centre Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Lower Saxony, Göttingen, Germany
| | - Vicente Grau
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford, UK
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Coleman JA, Doste R, Beltrami M, Argirò A, Coppini R, Olivotto I, Raman B, Bueno-Orovio A. Effects of ranolazine on the arrhythmic substrate in hypertrophic cardiomyopathy. Front Pharmacol 2024; 15:1379236. [PMID: 38659580 PMCID: PMC11039821 DOI: 10.3389/fphar.2024.1379236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024] Open
Abstract
Introduction: Hypertrophic cardiomyopathy (HCM) is a leading cause of lethal arrhythmias in the young. Although the arrhythmic substrate has been hypothesised to be amenable to late Na+ block with ranolazine, the specific mechanisms are not fully understood. Therefore, this study aimed to investigate the substrate mechanisms of safety and antiarrhythmic efficacy of ranolazine in HCM. Methods: Computational models of human tissue and ventricles were used to simulate the electrophysiological behaviour of diseased HCM myocardium for variable degrees of repolarisation impairment, validated against in vitro and clinical recordings. S1-S2 pacing protocols were used to quantify arrhythmic risk in scenarios of (i) untreated HCM-remodelled myocardium and (ii) myocardium treated with 3µM, 6µM and 10µM ranolazine, for variable repolarisation heterogeneity sizes and pacing rates. ECGs were derived from biventricular simulations to identify ECG biomarkers linked to antiarrhythmic effects. Results: 10µM ranolazine given to models manifesting ventricular tachycardia (VT) at baseline led to a 40% reduction in number of VT episodes on pooled analysis of >40,000 re-entry inducibility simulations. Antiarrhythmic efficacy and safety were dependent on the degree of repolarisation impairment, with optimal benefit in models with maximum JTc interval <370 ms. Ranolazine increased risk of VT only in models with severe-extreme repolarisation impairment. Conclusion: Ranolazine efficacy and safety may be critically dependent upon the degree of repolarisation impairment in HCM. For moderate repolarisation impairment, reductions in refractoriness heterogeneity by ranolazine may prevent conduction blocks and re-entry. With severe-extreme disease substrates, reductions of the refractory period can increase re-entry sustainability.
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Affiliation(s)
- James A. Coleman
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Ruben Doste
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Matteo Beltrami
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Alessia Argirò
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Raffaele Coppini
- Department of NeuroFarBa, University of Florence, Florence, Italy
| | - Iacopo Olivotto
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
- Meyer Children’s Hospital IRCCS, Florence, Italy
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
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Coleman JA, Doste R, Beltrami M, Coppini R, Olivotto I, Raman B, Bueno-Orovio A. Electrophysiological mechanisms underlying T wave pseudonormalisation on stress ECGs in hypertrophic cardiomyopathy. Comput Biol Med 2024; 169:107829. [PMID: 38096763 DOI: 10.1016/j.compbiomed.2023.107829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/09/2023] [Accepted: 12/04/2023] [Indexed: 02/08/2024]
Abstract
BACKGROUND Pseudonormal T waves may be detected on stress electrocardiograms (ECGs) in hypertrophic cardiomyopathy (HCM). Either myocardial ischaemia or purely exercise-induced changes have been hypothesised to contribute to this phenomenon, but the precise electrophysiological mechanisms remain unknown. METHODS Computational models of human HCM ventricles (n = 20) with apical and asymmetric septal hypertrophy phenotypes with variable severities of repolarisation impairment were used to investigate the effects of acute myocardial ischaemia on ECGs with T wave inversions at baseline. Virtual 12-lead ECGs were derived from a total of 520 biventricular simulations, for cases with regionally ischaemic K+ accumulation in hypertrophied segments, global exercise-induced serum K+ increases, and/or increased pacing frequency, to analyse effects on ECG biomarkers including ST segments, T wave amplitudes, and QT intervals. RESULTS Regional ischaemic K+ accumulation had a greater impact on T wave pseudonormalisation than exercise-induced serum K+ increases, due to larger reductions in repolarisation gradients. Increases in serum K+ and pacing rate partially corrected T waves in some anatomical and electrophysiological phenotypes. T wave morphology was more sensitive than ST segment elevation to regional K+ increases, suggesting that T wave pseudonormalisation may sometimes be an early, or the only, ECG feature of myocardial ischaemia in HCM. CONCLUSIONS Ischaemia-induced T wave pseudonormalisation can occur on stress ECG testing in HCM before significant ST segment changes. Some anatomical and electrophysiological phenotypes may enable T wave pseudonormalisation due to exercise-induced increased serum K+ and pacing rate. Consideration of dynamic T wave abnormalities could improve the detection of myocardial ischaemia in HCM.
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Affiliation(s)
- James A Coleman
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Ruben Doste
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Matteo Beltrami
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Raffaele Coppini
- Department of NeuroFarBa, University of Florence, Florence, Italy
| | - Iacopo Olivotto
- Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy; Meyer Children's Hospital IRCCS, Florence, Italy
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom
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Coleman JA, Ashkir Z, Raman B, Bueno-Orovio A. Mechanisms and prognostic impact of myocardial ischaemia in hypertrophic cardiomyopathy. Int J Cardiovasc Imaging 2023; 39:1979-1996. [PMID: 37358707 PMCID: PMC10589194 DOI: 10.1007/s10554-023-02894-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 06/03/2023] [Indexed: 06/27/2023]
Abstract
Despite the progress made in risk stratification, sudden cardiac death and heart failure remain dreaded complications for hypertrophic cardiomyopathy (HCM) patients. Myocardial ischaemia is widely acknowledged as a contributor to cardiovascular events, but the assessment of ischaemia is not yet included in HCM clinical guidelines. This review aims to evaluate the HCM-specific pro-ischaemic mechanisms and the potential prognostic value of imaging for myocardial ischaemia in HCM. A literature review was performed using PubMed to identify studies with non-invasive imaging of ischaemia (cardiovascular magnetic resonance, echocardiography, and nuclear imaging) in HCM, prioritising studies published after the last major review in 2009. Other studies, including invasive ischaemia assessment and post-mortem histology, were also considered for mechanistic or prognostic relevance. Pro-ischaemic mechanisms in HCM reviewed included the effects of sarcomeric mutations, microvascular remodelling, hypertrophy, extravascular compressive forces and left ventricular outflow tract obstruction. The relationship between ischaemia and fibrosis was re-appraised by considering segment-wise analyses in multimodal imaging studies. The prognostic significance of myocardial ischaemia in HCM was evaluated using longitudinal studies with composite endpoints, and reports of ischaemia-arrhythmia associations were further considered. The high prevalence of ischaemia in HCM is explained by several micro- and macrostructural pathological features, alongside mutation-associated energetic impairment. Ischaemia on imaging identifies a subgroup of HCM patients at higher risk of adverse cardiovascular outcomes. Ischaemic HCM phenotypes are a high-risk subgroup associated with more advanced left ventricular remodelling, but further studies are required to evaluate the independent prognostic value of non-invasive imaging for ischaemia.
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Affiliation(s)
- James A Coleman
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Zakariye Ashkir
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, University of Oxford, Oxford, UK
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Meng Z, Capel RA, Bose SJ, Bosch E, de Jong S, Planque R, Galione A, Burton RAB, Bueno-Orovio A. Lysosomal calcium loading promotes spontaneous calcium release by potentiating ryanodine receptors. Biophys J 2023; 122:3044-3059. [PMID: 37329137 PMCID: PMC10432190 DOI: 10.1016/j.bpj.2023.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 05/03/2023] [Accepted: 06/12/2023] [Indexed: 06/18/2023] Open
Abstract
Spontaneous calcium release by ryanodine receptors (RyRs) due to intracellular calcium overload results in delayed afterdepolarizations, closely associated with life-threatening arrhythmias. In this regard, inhibiting lysosomal calcium release by two-pore channel 2 (TPC2) knockout has been shown to reduce the incidence of ventricular arrhythmias under β-adrenergic stimulation. However, mechanistic investigations into the role of lysosomal function on RyR spontaneous release remain missing. We investigate the calcium handling mechanisms by which lysosome function modulates RyR spontaneous release, and determine how lysosomes are able to mediate arrhythmias by its influence on calcium loading. Mechanistic studies were conducted using a population of biophysically detailed mouse ventricular models including for the first time modeling of lysosomal function, and calibrated by experimental calcium transients modulated by TPC2. We demonstrate that lysosomal calcium uptake and release can synergistically provide a pathway for fast calcium transport, by which lysosomal calcium release primarily modulates sarcoplasmic reticulum calcium reuptake and RyR release. Enhancement of this lysosomal transport pathway promoted RyR spontaneous release by elevating RyR open probability. In contrast, blocking either lysosomal calcium uptake or release revealed an antiarrhythmic impact. Under conditions of calcium overload, our results indicate that these responses are strongly modulated by intercellular variability in L-type calcium current, RyR release, and sarcoplasmic reticulum calcium-ATPase reuptake. Altogether, our investigations identify that lysosomal calcium handling directly influences RyR spontaneous release by regulating RyR open probability, suggesting antiarrhythmic strategies and identifying key modulators of lysosomal proarrhythmic action.
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Affiliation(s)
- Zhaozheng Meng
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Rebecca A Capel
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Samuel J Bose
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Erik Bosch
- Department of Mathematics, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Sophia de Jong
- Department of Mathematics, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Robert Planque
- Department of Mathematics, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Rebecca A B Burton
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom.
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Pioner JM, Vitale G, Steczina S, Langione M, Margara F, Santini L, Giardini F, Lazzeri E, Piroddi N, Scellini B, Palandri C, Schuldt M, Spinelli V, Girolami F, Mazzarotto F, van der Velden J, Cerbai E, Tesi C, Olivotto I, Bueno-Orovio A, Sacconi L, Coppini R, Ferrantini C, Regnier M, Poggesi C. Slower Calcium Handling Balances Faster Cross-Bridge Cycling in Human MYBPC3 HCM. Circ Res 2023; 132:628-644. [PMID: 36744470 PMCID: PMC9977265 DOI: 10.1161/circresaha.122.321956] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 01/19/2023] [Accepted: 01/24/2023] [Indexed: 02/07/2023]
Abstract
BACKGROUND The pathogenesis of MYBPC3-associated hypertrophic cardiomyopathy (HCM) is still unresolved. In our HCM patient cohort, a large and well-characterized population carrying the MYBPC3:c772G>A variant (p.Glu258Lys, E258K) provides the unique opportunity to study the basic mechanisms of MYBPC3-HCM with a comprehensive translational approach. METHODS We collected clinical and genetic data from 93 HCM patients carrying the MYBPC3:c772G>A variant. Functional perturbations were investigated using different biophysical techniques in left ventricular samples from 4 patients who underwent myectomy for refractory outflow obstruction, compared with samples from non-failing non-hypertrophic surgical patients and healthy donors. Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes and engineered heart tissues (EHTs) were also investigated. RESULTS Haplotype analysis revealed MYBPC3:c772G>A as a founder mutation in Tuscany. In ventricular myocardium, the mutation leads to reduced cMyBP-C (cardiac myosin binding protein-C) expression, supporting haploinsufficiency as the main primary disease mechanism. Mechanical studies in single myofibrils and permeabilized muscle strips highlighted faster cross-bridge cycling, and higher energy cost of tension generation. A novel approach based on tissue clearing and advanced optical microscopy supported the idea that the sarcomere energetics dysfunction is intrinsically related with the reduction in cMyBP-C. Studies in single cardiomyocytes (native and hiPSC-derived), intact trabeculae and hiPSC-EHTs revealed prolonged action potentials, slower Ca2+ transients and preserved twitch duration, suggesting that the slower excitation-contraction coupling counterbalanced the faster sarcomere kinetics. This conclusion was strengthened by in silico simulations. CONCLUSIONS HCM-related MYBPC3:c772G>A mutation invariably impairs sarcomere energetics and cross-bridge cycling. Compensatory electrophysiological changes (eg, reduced potassium channel expression) appear to preserve twitch contraction parameters, but may expose patients to greater arrhythmic propensity and disease progression. Therapeutic approaches correcting the primary sarcomeric defects may prevent secondary cardiomyocyte remodeling.
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Affiliation(s)
- Josè Manuel Pioner
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- Department of Biology (J.M.P.), University of Florence, Italy
| | - Giulia Vitale
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Sonette Steczina
- Department of Bioengineering, University of Washington, Seattle, WA (S.S., M.R.)
| | - Marianna Langione
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Francesca Margara
- Department of Computer Science, University of Oxford, United Kingdom (F. Margara, A.B.-O.)
| | - Lorenzo Santini
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Francesco Giardini
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Erica Lazzeri
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Nicoletta Piroddi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Beatrice Scellini
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Chiara Palandri
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Maike Schuldt
- Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Physiology, The Netherlands (M.S., J.v.d.V.)
| | - Valentina Spinelli
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Francesca Girolami
- Pediatric Cardiology (F. Girolami), IRCCS Meyer Children’s Hospital, Florence, Italy
| | - Francesco Mazzarotto
- Department of Molecular and Translational Medicine, University of Brescia, Italy (F. Mazzarotto)
- National Heart and Lung Institute, Imperial College London, London, United Kingdom (F. Mazzarotto)
| | - Jolanda van der Velden
- Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Physiology, The Netherlands (M.S., J.v.d.V.)
| | - Elisabetta Cerbai
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Chiara Tesi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Iacopo Olivotto
- Cardiogenetics Unit (I.O.), IRCCS Meyer Children’s Hospital, Florence, Italy
- Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O.)
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, United Kingdom (F. Margara, A.B.-O.)
| | - Leonardo Sacconi
- Institute of Clinical Physiology (IFC), National Research Council, Florence, Italy (L. Sacconi)
- Institute for Experimental Cardiovascular Medicine, Faculty of Medicine, University of Freiburg (L. Sacconi)
| | - Raffaele Coppini
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Cecilia Ferrantini
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA (S.S., M.R.)
| | - Corrado Poggesi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
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9
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Lawson BA, dos Santos RW, Turner IW, Bueno-Orovio A, Burrage P, Burrage K. Homogenisation for the monodomain model in the presence of microscopic fibrotic structures. Commun Nonlinear Sci Numer Simul 2023; 116:None. [PMID: 37113591 PMCID: PMC10124103 DOI: 10.1016/j.cnsns.2022.106794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 05/06/2022] [Accepted: 08/04/2022] [Indexed: 06/08/2023]
Abstract
Computational models in cardiac electrophysiology are notorious for long runtimes, restricting the numbers of nodes and mesh elements in the numerical discretisations used for their solution. This makes it particularly challenging to incorporate structural heterogeneities on small spatial scales, preventing a full understanding of the critical arrhythmogenic effects of conditions such as cardiac fibrosis. In this work, we explore the technique of homogenisation by volume averaging for the inclusion of non-conductive micro-structures into larger-scale cardiac meshes with minor computational overhead. Importantly, our approach is not restricted to periodic patterns, enabling homogenised models to represent, for example, the intricate patterns of collagen deposition present in different types of fibrosis. We first highlight the importance of appropriate boundary condition choice for the closure problems that define the parameters of homogenised models. Then, we demonstrate the technique's ability to correctly upscale the effects of fibrotic patterns with a spatial resolution of 10 µm into much larger numerical mesh sizes of 100- 250 µm . The homogenised models using these coarser meshes correctly predict critical pro-arrhythmic effects of fibrosis, including slowed conduction, source/sink mismatch, and stabilisation of re-entrant activation patterns. As such, this approach to homogenisation represents a significant step towards whole organ simulations that unravel the effects of microscopic cardiac tissue heterogeneities.
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Affiliation(s)
- Brodie A.J. Lawson
- Centre for Data Science, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- School of Mathematical Sciences, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
| | - Rodrigo Weber dos Santos
- Graduate Program on Computational Modelling, Universidade de Federal de Juiz de Fora, Rua Jose Lourenco Kelmer s/n, Juiz de Fora, 36036-900, Minas Gerais, Brazil
| | - Ian W. Turner
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- School of Mathematical Sciences, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Parks Rd, Oxford, OX1 3QD, Oxfordshire, United Kingdom
| | - Pamela Burrage
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- School of Mathematical Sciences, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
| | - Kevin Burrage
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- School of Mathematical Sciences, Queensland University of Technology, 2 George Street, Brisbane, 4000, Queensland, Australia
- Department of Computer Science, University of Oxford, Parks Rd, Oxford, OX1 3QD, Oxfordshire, United Kingdom
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10
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Beetz M, Corral Acero J, Banerjee A, Eitel I, Zacur E, Lange T, Stiermaier T, Evertz R, Backhaus SJ, Thiele H, Bueno-Orovio A, Lamata P, Schuster A, Grau V. Interpretable cardiac anatomy modeling using variational mesh autoencoders. Front Cardiovasc Med 2022; 9:983868. [PMID: 36620629 PMCID: PMC9813669 DOI: 10.3389/fcvm.2022.983868] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/24/2022] [Indexed: 12/24/2022] Open
Abstract
Cardiac anatomy and function vary considerably across the human population with important implications for clinical diagnosis and treatment planning. Consequently, many computer-based approaches have been developed to capture this variability for a wide range of applications, including explainable cardiac disease detection and prediction, dimensionality reduction, cardiac shape analysis, and the generation of virtual heart populations. In this work, we propose a variational mesh autoencoder (mesh VAE) as a novel geometric deep learning approach to model such population-wide variations in cardiac shapes. It embeds multi-scale graph convolutions and mesh pooling layers in a hierarchical VAE framework to enable direct processing of surface mesh representations of the cardiac anatomy in an efficient manner. The proposed mesh VAE achieves low reconstruction errors on a dataset of 3D cardiac meshes from over 1,000 patients with acute myocardial infarction, with mean surface distances between input and reconstructed meshes below the underlying image resolution. We also find that it outperforms a voxelgrid-based deep learning benchmark in terms of both mean surface distance and Hausdorff distance while requiring considerably less memory. Furthermore, we explore the quality and interpretability of the mesh VAE's latent space and showcase its ability to improve the prediction of major adverse cardiac events over a clinical benchmark. Finally, we investigate the method's ability to generate realistic virtual populations of cardiac anatomies and find good alignment between the synthesized and gold standard mesh populations in terms of multiple clinical metrics.
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Affiliation(s)
- Marcel Beetz
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Jorge Corral Acero
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Abhirup Banerjee
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ingo Eitel
- University Heart Center Lübeck, Medical Clinic II, Cardiology, Angiology, and Intensive Care Medicine, Lübeck, Germany
- University Hospital Schleswig-Holstein, Lübeck, Germany
- German Centre for Cardiovascular Research, Partner Site Lübeck, Lübeck, Germany
| | - Ernesto Zacur
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Torben Lange
- Department of Cardiology and Pneumology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research, Partner Site Göttingen, Göttingen, Germany
| | - Thomas Stiermaier
- University Heart Center Lübeck, Medical Clinic II, Cardiology, Angiology, and Intensive Care Medicine, Lübeck, Germany
- University Hospital Schleswig-Holstein, Lübeck, Germany
- German Centre for Cardiovascular Research, Partner Site Lübeck, Lübeck, Germany
| | - Ruben Evertz
- Department of Cardiology and Pneumology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research, Partner Site Göttingen, Göttingen, Germany
| | - Sören J. Backhaus
- Department of Cardiology and Pneumology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research, Partner Site Göttingen, Göttingen, Germany
| | - Holger Thiele
- Department of Internal Medicine/Cardiology, Heart Center Leipzig at University of Leipzig, Leipzig, Germany
- Leipzig Heart Institute, Leipzig, Germany
| | | | - Pablo Lamata
- Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Andreas Schuster
- Department of Cardiology and Pneumology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
- German Centre for Cardiovascular Research, Partner Site Göttingen, Göttingen, Germany
| | - Vicente Grau
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
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11
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Doste R, Coppini R, Bueno-Orovio A. Remodelling of potassium currents underlies arrhythmic action potential prolongation under beta-adrenergic stimulation in hypertrophic cardiomyopathy. J Mol Cell Cardiol 2022; 172:120-131. [PMID: 36058298 DOI: 10.1016/j.yjmcc.2022.08.361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 08/15/2022] [Accepted: 08/27/2022] [Indexed: 12/14/2022]
Abstract
Hypertrophic cardiomyopathy (HCM) patients often present an enhanced arrhythmogenicity that can lead to lethal arrhythmias, especially during exercise. Recent studies have indicated an abnormal response of HCM cardiomyocytes to β-adrenergic receptor stimulation (β-ARS), with prolongation of their action potential rather than shortening. The mechanisms underlying this aberrant response to sympathetic stimulation and its possible proarrhythmic role remain unknown. The aims of this study are to investigate the key ionic mechanisms underlying the HCM abnormal response to β-ARS and the resultant repolarisation abnormalities using human-based experimental and computational methodologies. We integrated and calibrated the latest models of human ventricular electrophysiology and β-ARS using experimental measurements of human adult cardiomyocytes from control and HCM patients. Our major findings include: (1) the developed in silico models of β-ARS capture the behaviour observed in the experimental data, including the aberrant response of HCM cardiomyocytes to β-ARS; (2) the reduced increase of potassium currents under β-ARS was identified as the main mechanism of action potential prolongation in HCM, rather than a more sustained inward calcium current; (3) action potential duration differences between healthy and HCM cardiomyocytes were increased upon β-ARS, while endocardial to epicardial differences in HCM cardiomyocytes were reduced; (4) models presenting repolarisation abnormalities were characterised by downregulation of the rapid delayed rectifier potassium current and the sodium‑potassium pump, while inward currents were upregulated. In conclusion, our results identify causal relationships between the HCM phenotype and its arrhythmogenic response to β-ARS through the downregulation of potassium currents.
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Affiliation(s)
- Ruben Doste
- Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | | | - Alfonso Bueno-Orovio
- Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, United Kingdom.
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12
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Dasi A, Roy A, Bueno-Orovio A, Rodriguez B. Electrocardiogram metrics identify ionic current dysregulation relevant to atrial fibrillation. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Personalisation of pharmacological treatment for atrial fibrillation (AF) is challenging. Pharmacological ionic current blockers such as digoxin or flecainide are commonly used, with caution given possible cardiotoxicity and proarrhythmia. Moreover, patients are stratified based on their associated heart disease rather than individual electrophysiological substrate, in part due to the inability for its non-invasive characterisation. Here we hypothesise that the ECG may contain information on key ionic currents regulating AF initiation and sustenance, and which would enable personalisation of pharmacological treatments to increase safety and efficacy.
Purpose
To identify clinical ECG markers that reflect dysregulation of key ionic currents for AF using modelling and simulation in populations of whole-atria models without structural heart disease.
Methods
Experimental data obtained from human AF and control patients was used to develop a virtual population of 200 whole-atria models (Figure, organ-level) with individual ionic profiles (Figure 1, bottom-left), including electrophysiological regional inhomogeneities (Figure 1, bottom-right). Modified-limb 12 lead ECGs were computed during sinus rhythm (Figure 1, body-surface-level) and biomarkers were quantified for the P and Ta-waves, such as duration, time-to-peak, decay, dispersion, amplitude and P-wave terminal force.
Results
Simulated modified-limb ECG consistently reproduced the clinical ECG observed in human subjects, with an apparent Ta-wave inversion in lead II (Figure 1, body-surface-level). The inward rectified K+ current (IK1), known to be critical for AF, was the only ionic current associated with Ta-wave duration, showing an inversely proportional relationship (236±48 vs. 466±53 ms, IK1 up-regulation vs. down-regulation in lead V5; median ± interquartile range; P<0.001). Elevated IK1 additionally yield Ta-wave inversion in lead V5 and a higher Ta-wave magnitude in lead II (0.15±0.03 vs. 0.07±0.04 mV, IK1 up-regulation vs. down-regulation; P<0.001). However, Ta-wave magnitude showed a predominant relationship with the Na+/K+ pump (INaK), especially in the precordial leads (0.17±0.13 vs. 0.07±0.04 mV, INaK up-regulation vs. down-regulation in V5; P<0.001). Thus, the up-regulation of both currents led to very short, high-amplitude Ta-waves. While elevated IK1 additionally increased the P-wave terminal force (1.58±0.37 vs. 1.31±0.33 mV ms, IK1 up-regulation vs. down-regulation; P<0.001), a higher increase was observed for decreased fast Na+ current (INa) (1.35±0.17 vs. 1.86±0.30 mV ms, INa up-regulation vs. down-regulation; P<0.001).
Conclusion
Ta-wave duration and amplitude are revealing of IK1 and INaK dysregulation, respectively, holding potential for improving cardiac safety and efficacy through a better stratification of AF patients for pharmacological treatment.
Funding Acknowledgement
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 860974
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Affiliation(s)
- A Dasi
- University of Oxford , Oxford , United Kingdom
| | - A Roy
- University of Oxford , Oxford , United Kingdom
| | | | - B Rodriguez
- University of Oxford , Oxford , United Kingdom
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13
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Dasí A, Roy A, Sachetto R, Camps J, Bueno-Orovio A, Rodriguez B. In-silico drug trials for precision medicine in atrial fibrillation: From ionic mechanisms to electrocardiogram-based predictions in structurally-healthy human atria. Front Physiol 2022; 13:966046. [PMID: 36187798 PMCID: PMC9522526 DOI: 10.3389/fphys.2022.966046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Atrial fibrillation (AF) inducibility, sustainability and response to pharmacological treatment of individual patients are expected to be determined by their ionic current properties, especially in structurally-healthy atria. Mechanisms underlying AF and optimal cardioversion are however still unclear. In this study, in-silico drug trials were conducted using a population of human structurally-healthy atria models to 1) identify key ionic current properties determining AF inducibility, maintenance and pharmacological cardioversion, and 2) compare the prognostic value for predicting individual AF cardioversion of ionic current properties and electrocardiogram (ECG) metrics. In the population of structurally-healthy atria, 477 AF episodes were induced in ionic current profiles with both steep action potential duration (APD) restitution (eliciting APD alternans), and high excitability (enabling propagation at fast rates that transformed alternans into discordant). High excitability also favored 211 sustained AF episodes, so its decrease, through prolonged refractoriness, explained pharmacological cardioversion. In-silico trials over 200 AF episodes, 100 ionic profiles and 10 antiarrhythmic compounds were consistent with previous clinical trials, and identified optimal treatments for individual electrophysiological properties of the atria. Algorithms trained on 211 simulated AF episodes exhibited >70% accuracy in predictions of cardioversion for individual treatments using either ionic current profiles or ECG metrics. In structurally-healthy atria, AF inducibility and sustainability are enabled by discordant alternans, under high excitability and steep restitution conditions. Successful pharmacological cardioversion is predicted with 70% accuracy from either ionic or ECG properties, and it is optimal for treatments maximizing refractoriness (thus reducing excitability) for the given ionic current profile of the atria.
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Affiliation(s)
- Albert Dasí
- Department of Computer Science, University of Oxford, Oxford, United Kingdom,*Correspondence: Blanca Rodriguez, ; Albert Dasí,
| | - Aditi Roy
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Rafael Sachetto
- Departamento de Ciência da Computação, Universidade Federal De São João Del-Rei, São João del Rei, Brazil
| | - Julia Camps
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | | | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom,*Correspondence: Blanca Rodriguez, ; Albert Dasí,
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14
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Corral Acero J, Schuster A, Zacur E, Lange T, Stiermaier T, Backhaus SJ, Thiele H, Bueno-Orovio A, Lamata P, Eitel I, Grau V. Understanding and Improving Risk Assessment After Myocardial Infarction Using Automated Left Ventricular Shape Analysis. JACC Cardiovasc Imaging 2022; 15:1563-1574. [PMID: 35033494 PMCID: PMC9444994 DOI: 10.1016/j.jcmg.2021.11.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Left ventricular ejection fraction (LVEF) and end-systolic volume (ESV) remain the main imaging biomarkers for post-acute myocardial infarction (AMI) risk stratification. However, they are limited to global systolic function and fail to capture functional and anatomical regional abnormalities, hindering their performance in risk stratification. OBJECTIVES This study aimed to identify novel 3-dimensional (3D) imaging end-systolic (ES) shape and contraction descriptors toward risk-related features and superior prognosis in AMI. METHODS A multicenter cohort of AMI survivors (n = 1,021; median age 63 years; 74.5% male) who underwent cardiac magnetic resonance (CMR) at a median of 3 days after infarction were considered for this study. The clinical endpoint was the 12-month rate of major adverse cardiac events (MACE; n = 73), consisting of all-cause death, reinfarction, and new congestive heart failure. A fully automated pipeline was developed to segment CMR images, build 3D statistical models of shape and contraction in AMI, and find the 3D patterns related to MACE occurrence. RESULTS The novel ES shape markers proved to be superior to ESV (median cross-validated area under the receiver-operating characteristic curve 0.681 [IQR: 0.679-0.684] vs 0.600 [IQR: 0.598-0.602]; P < 0.001); and 3D contraction to LVEF (0.716 [IQR: 0.714-0.718] vs 0.681 [IQR: 0.679-0.684]; P < 0.001) in MACE occurrence prediction. They also contributed to a significant improvement in a multivariable setting including CMR markers, cardiovascular risk factors, and basic patient characteristics (0.747 [IQR: 0.745-0.749]; P < 0.001). Based on these novel 3D descriptors, 3 impairments caused by AMI were identified: global, anterior, and basal, the latter being the most complementary signature to already known predictors. CONCLUSIONS The quantification of 3D differences in ES shape and contraction, enabled by a fully automated pipeline, improves post-AMI risk prediction and identifies shape and contraction patterns related to MACE occurrence.
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Affiliation(s)
- Jorge Corral Acero
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom.
| | - Andreas Schuster
- University Medical Center Göttingen, Department of Cardiology and Pneumology, Georg-August University, Göttingen, Germany; German Centre for Cardiovascular Research, Göttingen, Germany
| | - Ernesto Zacur
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Torben Lange
- University Medical Center Göttingen, Department of Cardiology and Pneumology, Georg-August University, Göttingen, Germany; German Centre for Cardiovascular Research, Göttingen, Germany
| | - Thomas Stiermaier
- University Heart Center Lübeck, Medical Clinic II, Cardiology, Angiology, and Intensive Care Medicine, Lübeck, Germany; University Hospital Schleswig-Holstein, Lübeck, Germany; German Centre for Cardiovascular Research, Lübeck, Germany
| | - Sören J Backhaus
- University Medical Center Göttingen, Department of Cardiology and Pneumology, Georg-August University, Göttingen, Germany; German Centre for Cardiovascular Research, Göttingen, Germany
| | - Holger Thiele
- Heart Center Leipzig at University of Leipzig, Department of Internal Medicine and Cardiology, Leipzig, Germany; Leipzig Heart Institute, Leipzig, Germany
| | | | - Pablo Lamata
- Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Ingo Eitel
- University Heart Center Lübeck, Medical Clinic II, Cardiology, Angiology, and Intensive Care Medicine, Lübeck, Germany; University Hospital Schleswig-Holstein, Lübeck, Germany; German Centre for Cardiovascular Research, Lübeck, Germany
| | - Vicente Grau
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
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15
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Farquhar ME, Burrage K, Weber Dos Santos R, Bueno-Orovio A, Lawson BA. Graph-based homogenisation for modelling cardiac fibrosis. J Comput Phys 2022; 459:None. [PMID: 35959500 PMCID: PMC9352598 DOI: 10.1016/j.jcp.2022.111126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/15/2022] [Accepted: 03/02/2022] [Indexed: 05/02/2023]
Abstract
Fibrosis, the excess of extracellular matrix, can affect, and even block, propagation of action potential in cardiac tissue. This can result in deleterious effects on heart function, but the nature and severity of these effects depend strongly on the localisation of fibrosis and its by-products in cardiac tissue, such as collagen scar formation. Computer simulation is an important means of understanding the complex effects of fibrosis on activation patterns in the heart, but concerns of computational cost place restrictions on the spatial resolution of these simulations. In this work, we present a novel numerical homogenisation technique that uses both Eikonal and graph approaches to allow fine-scale heterogeneities in conductivity to be incorporated into a coarser mesh. Homogenisation achieves this by deriving effective conductivity tensors so that a coarser mesh can then be used for numerical simulation. By taking a graph-based approach, our homogenisation technique functions naturally on irregular grids and does not rely upon any assumptions of periodicity, even implicitly. We present results of action potential propagation through fibrotic tissue in two dimensions that show the graph-based homogenisation technique is an accurate and effective way to capture fine-scale domain information on coarser meshes in the context of sharp-fronted travelling waves of activation. As test problems, we consider excitation propagation in tissue with diffuse fibrosis and through a tunnel-like structure designed to test homogenisation, interaction of an excitation wave with a scar region, and functional re-entry.
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Affiliation(s)
- Megan E. Farquhar
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
| | - Kevin Burrage
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
- Department of Computer Science, Oxford University, Oxford, United Kingdom
| | - Rodrigo Weber Dos Santos
- Department of Computer Science and Program on Computational Modeling, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | | | - Brodie A.J. Lawson
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, Australia
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16
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Coppini R, Beltrami M, Doste R, Bueno-Orovio A, Ferrantini C, Vitale G, Pioner JM, Santini L, Argirò A, Berteotti M, Mori F, Marchionni N, Stefàno P, Cerbai E, Poggesi C, Olivotto I. Paradoxical prolongation of QT interval during exercise in patients with hypertrophic cardiomyopathy: cellular mechanisms and implications for diastolic function. European Heart Journal Open 2022; 2:oeac034. [PMID: 35919344 PMCID: PMC9242073 DOI: 10.1093/ehjopen/oeac034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/14/2022] [Indexed: 11/21/2022]
Abstract
Aims Ventricular cardiomyocytes from hypertrophic cardiomyopathy (HCM) patient hearts show prolonged action potential duration (APD), impaired intracellular Ca2+ homeostasis and abnormal electrical response to beta -adrenergic stimulation. We sought to determine whether this behaviour is associated with abnormal changes of repolarization during exercise and worsening of diastolic function, ultimately explaining the intolerance to exercise experienced by some patients without obstruction. Methods and results Non-obstructive HCM patients (178) and control subjects (81) underwent standard exercise testing, including exercise echocardiography. Ventricular myocytes were isolated from myocardial samples of 23 HCM and eight non-failing non-hypertrophic surgical patients. The APD shortening in response to high frequencies was maintained in HCM myocytes, while β-adrenergic stimulation unexpectedly prolonged APDs, ultimately leading to a lesser shortening of APDs in response to exercise. In HCM vs. control subjects, we observed a lesser shortening of QT interval at peak exercise (QTc: +27 ± 52 ms in HCM, −4 ± 50 ms in controls, P < 0.0001). In patients showing a marked QTc prolongation (>30 ms), the excessive shortening of the electrical diastolic period was linked with a limited increase of heart-rate and deterioration of diastolic function at peak effort. Conclusions Abnormal balance of Ca2+- and K+-currents in HCM cardiomyocytes determines insufficient APD and Ca2+-transient shortening with exercise. In HCM patients, exercise-induced QTc prolongation was associated with impaired diastolic reserve, contributing to the reduced exercise tolerance. Our results support the idea that severe electrical cardiomyocyte abnormalities underlie exercise intolerance in a subgroup of HCM patients without obstruction.
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Affiliation(s)
- Raffaele Coppini
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Matteo Beltrami
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Ruben Doste
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd , Oxford OX1 3QD, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd , Oxford OX1 3QD, UK
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Josè Manuel Pioner
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Lorenzo Santini
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Alessia Argirò
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Martina Berteotti
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Fabio Mori
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Niccolò Marchionni
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Pierluigi Stefàno
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Elisabetta Cerbai
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Iacopo Olivotto
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
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Passini E, Zhou X, Trovato C, Delaunois A, Valentin JP, Bueno-Orovio A, Rodriguez B. Evaluation of four in silico biomarkers for drug-induced proarrhythmic risk: COVID-19 off-label therapies case study. J Pharmacol Toxicol Methods 2021. [DOI: 10.1016/j.vascn.2021.107052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Margara F, Psaras Y, Rodriguez B, Toepfer CN, Bueno-Orovio A. Combining human-based in silico and in vitro models of inherited cardiac diseases for drug safety and efficacy evaluation. J Pharmacol Toxicol Methods 2021. [DOI: 10.1016/j.vascn.2021.107048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Psaras Y, Margara F, Cicconet M, Sparrow AJ, Repetti GG, Schmid M, Steeples V, Wilcox JA, Bueno-Orovio A, Redwood CS, Watkins HC, Robinson P, Rodriguez B, Seidman JG, Seidman CE, Toepfer CN. CalTrack: High-Throughput Automated Calcium Transient Analysis in Cardiomyocytes. Circ Res 2021; 129:326-341. [PMID: 34018815 PMCID: PMC8260473 DOI: 10.1161/circresaha.121.318868] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/06/2021] [Accepted: 05/20/2021] [Indexed: 11/21/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Yiangos Psaras
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
| | - Francesca Margara
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
| | - Marcelo Cicconet
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Image and Data Analysis Core (M.C.), Harvard Medical School, Boston, MA
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Alexander J. Sparrow
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Image and Data Analysis Core (M.C.), Harvard Medical School, Boston, MA
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Giuliana G. Repetti
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
| | - Manuel Schmid
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Image and Data Analysis Core (M.C.), Harvard Medical School, Boston, MA
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Violetta Steeples
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Image and Data Analysis Core (M.C.), Harvard Medical School, Boston, MA
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Jonathan A.L. Wilcox
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
| | | | - Charles S. Redwood
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Image and Data Analysis Core (M.C.), Harvard Medical School, Boston, MA
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Hugh C. Watkins
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
| | - Paul Robinson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
| | - Blanca Rodriguez
- Computer Science (F.M., A.B.-O., B.R.), University of Oxford, United Kingdom
| | - Jonathan G. Seidman
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
| | - Christine E. Seidman
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
- Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, MA (C.E.S.)
- Howard Hughes Medical Institute, Chevy Chase, MD (C.E.S.)
| | - Christopher N. Toepfer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (Y.P., F.M., A.J.S., M.S., V.S., C.S.R., H.C.W., P.R., C.N.T.), University of Oxford, United Kingdom
- Wellcome Centre for Human Genetics (H.C.W., C.N.T.), University of Oxford, United Kingdom
- Genetics (G.G.R., J.A.L.W., J.G.S., C.E.S., C.N.T.), Harvard Medical School, Boston, MA
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Margara F, Psaras Y, Rodriguez B, Toepfer CN, Bueno-Orovio A. Human-based computational and experimental investigation of disease mechanisms in mutation-specific hypertrophic cardiomyopathy. Europace 2021. [DOI: 10.1093/europace/euab116.537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement 764738. British Heart Foundation Intermediate Basic Science Fellowship (FS/17/22/32644).
Background
The pathogenic TNNI3R21C/+ variant causes malignant hypertrophic cardiomyopathy (HCM) with high incidence of sudden cardiac death, even in individuals absent of hypertrophy. There is evidence to support a known biophysical defect in the protein, yet the cellular mechanisms that precipitate adverse clinical outcomes remain unclear.
Purpose
We aim to computationally model and map the TNNI3R21C/+ cellular phenotype observed in induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) to human disease, thereby explaining the key mechanisms driving HCM in TNNI3R21C/+ variant carriers.
Methods
Wild-type (WT) and TNNI3R21C/+ iPSC-CMs were characterised by calcium transient analysis and direct sarcomere tracking to assess cellular contraction and relaxation. In-vitro data was used to inform the in-silico modelling of human cardiomyocytes. We constructed an in-silico population of WT adult cardiomyocytes and used it to transform the in-vitro data into corresponding adult phenotypes by means of a novel iPSC-to-adult data mapping. We tested the hypothesis that the abnormal TNNI3R21C/+ phenotype observed in iPSC-CMs would be explained by alterations in calcium affinity of troponin and increased myofilament calcium sensitivity.
Results
Analysis of in-vitro iPSC-CM data showed that TNNI3R21C/+ cells exhibit increased contractility with slowed relaxation when compared to WT. They also exhibited a faster rise in the calcium transient with a slowed calcium decay in comparison to WT. The in-silico adult TNNI3R21C/+ phenotype from the iPSC-to-adult mapping replicated the abnormalities observed in iPSC-CMs. The WT in-silico population accurately covered the ranges of electromechanical biomarkers providing a representative cohort of physiological variability. The TNNI3R21C/+ calcium phenotype could be recovered by our in-silico mutant models. Simulation results suggest that calcium abnormalities in TNNI3R21C/+ are a direct consequence of abnormal calcium buffering by thin filaments, mediated by increases in calcium affinity of troponin and myofilament calcium sensitivity. The TNNI3R21C/+ phenotype could not be recovered if these two factors were considered in isolation. Corresponding contractility analyses of in-silico models showed that the calcium level changes caused by the TNNI3R21C/+ phenotype are associated with hypercontractility and diastolic dysfunction, well-known hallmarks of HCM, which were also observed in the iPSC-CM model of disease.
Conclusions
This study showcases human-based computational and experimental methodologies that unearth direct mechanistic explanations of phenotypes driven by the TNNI3R21C/+ HCM variant. We show that the TNNI3R21C/+ HCM-causing mutation exhibits multifactorial remodelling of troponin calcium affinity and myofilament calcium sensitivity. Unearthing mechanistic pathways in mutation-specific HCM will be key to develop effective pharmacological interventions for a wide variety of understudied variants.
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Affiliation(s)
- F Margara
- University of Oxford, Department of Computer Science, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - Y Psaras
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - B Rodriguez
- University of Oxford, Department of Computer Science, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - CN Toepfer
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - A Bueno-Orovio
- University of Oxford, Department of Computer Science, Oxford, United Kingdom of Great Britain & Northern Ireland
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Doste R, Coppini R, Bueno-Orovio A. Characterization and modelling of the abnormal electrophysiological response under beta-adrenergic stimulation in hypertrophic cardiomyopathy. Europace 2021. [DOI: 10.1093/europace/euab116.572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): British Heart Foundation
Introduction
Hypertrophic Cardiomyopathy (HCM) is the most common inheritable heart pathology and the main cause of sudden cardiac death in young adults. HCM patients often present an enhanced arrhythmogenicity that can lead to lethal arrhythmias, especially during exercise. Recent studies have shown an abnormal response of HCM myocytes to β-adrenergic stimulation (β-ARS), with prolongation of their action potential duration (APD). The mechanisms underlying this aberrant response to sympathetic stimulation remain unknown.
Purpose
To investigate the key ionic mechanisms underlying the HCM abnormal response to β-ARS using human-based experimental and computational methodologies.
Methods
Experimental ionic currents, action potential and calcium transient were recorded in human adult cardiomyocytes from control and HCM patients. Isoproterenol (10-7 mol/L) was used to elicit β-ARS. Whole-cell ruptured patch voltage clamp experiments were conducted to characterise L-type calcium and potassium currents, with recordings performed before and after 3 min of drug exposure. The latest models of human ventricular electrophysiology and beta-adrenergic receptor signalling were integrated and calibrated using the human measured data. Simulations under isoproterenol were performed to quantify the effects of β-ARS on the action potential and calcium transient. The role of the main ion currents affected by β-ARS and by HCM remodelling was evaluated.
Results
In vitro, isoproterenol shortened APD (-16 ± 3%) in control, while prolonging APD in HCM myocytes (+23 ± 8%). Analysis of the measured data indicated two possible mechanisms contributing to APD prolongation in HCM myocytes. Firstly, a protracted L-type calcium current, presenting slower inactivation kinetics in HCM compared to control. The relative increase of potassium currents under β-ARS was also lower in HCM myocytes. The developed in silico models of β-ARS replicated the behaviour observed in the experimental data, based on slower L-type calcium current inactivation kinetics and a smaller increase of potassium currents in HCM. In absence of β-ARS, simulated HCM cardiomyocytes exhibited prolonged APD compared to control (525 ± 88 vs 281 ± 56 ms, p < 0.001). Under β-ARS, APD in control was reduced (-16.46%), whereas APD was prolonged in HCM (+11.63%). Further analysis showed that the reduction of the potassium currents increment under β-ARS was the main cause of the APD prolongation in HCM myocytes, with L-type calcium inactivation minimally contributing to APD prolongation.
Conclusions
In this study we assessed the effects of β-ARS on ion currents and APD in control and HCM myocytes. Our modelling results suggest that the increase of potassium repolarising currents under β-ARS is greatly reduced in HCM cardiomyocytes, being the main mechanism underlying their APD prolongation. This APD prolongation may have severe consequences in HCM patients, increasing the risk of exercise-induced arrhythmias. Abstract Figure.
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Affiliation(s)
- R Doste
- University of Oxford, Department of Computer Science, Oxford, United Kingdom of Great Britain & Northern Ireland
| | - R Coppini
- University of Florence, Department of Neuroscience, Psychology, Drug Sciences and Child Health , Florence, Italy
| | - A Bueno-Orovio
- University of Oxford, Department of Computer Science, Oxford, United Kingdom of Great Britain & Northern Ireland
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Abstract
Cardiotoxicity, defined as toxicity that affects the heart, is one of the most common adverse drug effects. Numerous drugs have been shown to have the potential to induce lethal arrhythmias by affecting cardiac electrophysiology, which is the focus of current preclinical testing. However, a substantial number of drugs can also affect cardiac function beyond electrophysiology. Within this broader sense of cardiotoxicity, this review discusses the key drug-protein interactions known to be involved in cardiotoxic drug response. We cover adverse effects of anticancer, central nervous system, genitourinary system, gastrointestinal, antihistaminic, anti-inflammatory, and anti-infective agents, illustrating that many share mechanisms of cardiotoxicity, including contractility, mitochondrial function, and cellular signaling.
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Affiliation(s)
| | - Blanca Rodriguez
- Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, BHF Centre of Research Excellence, University of Oxford, Oxford, UK
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Corral-Acero J, Margara F, Marciniak M, Rodero C, Loncaric F, Feng Y, Gilbert A, Fernandes JF, Bukhari HA, Wajdan A, Martinez MV, Santos MS, Shamohammdi M, Luo H, Westphal P, Leeson P, DiAchille P, Gurev V, Mayr M, Geris L, Pathmanathan P, Morrison T, Cornelussen R, Prinzen F, Delhaas T, Doltra A, Sitges M, Vigmond EJ, Zacur E, Grau V, Rodriguez B, Remme EW, Niederer S, Mortier P, McLeod K, Potse M, Pueyo E, Bueno-Orovio A, Lamata P. The 'Digital Twin' to enable the vision of precision cardiology. Eur Heart J 2020; 41:4556-4564. [PMID: 32128588 PMCID: PMC7774470 DOI: 10.1093/eurheartj/ehaa159] [Citation(s) in RCA: 185] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/29/2019] [Accepted: 02/24/2020] [Indexed: 12/26/2022] Open
Abstract
Providing therapies tailored to each patient is the vision of precision medicine, enabled by the increasing ability to capture extensive data about individual patients. In this position paper, we argue that the second enabling pillar towards this vision is the increasing power of computers and algorithms to learn, reason, and build the 'digital twin' of a patient. Computational models are boosting the capacity to draw diagnosis and prognosis, and future treatments will be tailored not only to current health status and data, but also to an accurate projection of the pathways to restore health by model predictions. The early steps of the digital twin in the area of cardiovascular medicine are reviewed in this article, together with a discussion of the challenges and opportunities ahead. We emphasize the synergies between mechanistic and statistical models in accelerating cardiovascular research and enabling the vision of precision medicine.
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Affiliation(s)
| | - Francesca Margara
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Maciej Marciniak
- Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Cristobal Rodero
- Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Filip Loncaric
- Institut Clínic Cardiovascular, Hospital Clínic, Universitat de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Yingjing Feng
- IHU Liryc, Electrophysiology and Heart Modeling Institute, fondation Bordeaux Université, Pessac-Bordeaux F-33600, France
- IMB, UMR 5251, University of Bordeaux, Talence F-33400, France
| | | | - Joao F Fernandes
- Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Hassaan A Bukhari
- IMB, UMR 5251, University of Bordeaux, Talence F-33400, France
- Aragón Institute of Engineering Research, Universidad de Zaragoza, IIS Aragón, Zaragoza, Spain
| | - Ali Wajdan
- The Intervention Centre, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | | | | | - Mehrdad Shamohammdi
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Hongxing Luo
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Philip Westphal
- Medtronic PLC, Bakken Research Center, Maastricht, the Netherlands
| | - Paul Leeson
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine, Oxford Cardiovascular Clinical Research Facility, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Paolo DiAchille
- Healthcare and Life Sciences Research, IBM T.J. Watson Research Center, Yorktown Heights, NY, USA
| | - Viatcheslav Gurev
- Healthcare and Life Sciences Research, IBM T.J. Watson Research Center, Yorktown Heights, NY, USA
| | - Manuel Mayr
- King’s British Heart Foundation Centre, King’s College London, London, UK
| | - Liesbet Geris
- Virtual Physiological Human Institute, Leuven, Belgium
| | - Pras Pathmanathan
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Tina Morrison
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | | | - Frits Prinzen
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Tammo Delhaas
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Ada Doltra
- Institut Clínic Cardiovascular, Hospital Clínic, Universitat de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Marta Sitges
- Institut Clínic Cardiovascular, Hospital Clínic, Universitat de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- CIBERCV, Instituto de Salud Carlos III, (CB16/11/00354), CERCA Programme/Generalitat de, Catalunya, Spain
| | - Edward J Vigmond
- IHU Liryc, Electrophysiology and Heart Modeling Institute, fondation Bordeaux Université, Pessac-Bordeaux F-33600, France
- IMB, UMR 5251, University of Bordeaux, Talence F-33400, France
| | - Ernesto Zacur
- Department of Engineering Science, University of Oxford, Oxford, UK
| | - Vicente Grau
- Department of Engineering Science, University of Oxford, Oxford, UK
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Espen W Remme
- The Intervention Centre, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Steven Niederer
- Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | | | | | - Mark Potse
- IHU Liryc, Electrophysiology and Heart Modeling Institute, fondation Bordeaux Université, Pessac-Bordeaux F-33600, France
- IMB, UMR 5251, University of Bordeaux, Talence F-33400, France
- Inria Bordeaux Sud-Ouest, CARMEN team, Talence F-33400, France
| | - Esther Pueyo
- Aragón Institute of Engineering Research, Universidad de Zaragoza, IIS Aragón, Zaragoza, Spain
- CIBER in Bioengineering, Biomaterials and Nanomedicine (CIBER‐BBN), Madrid, Spain
| | - Alfonso Bueno-Orovio
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Pablo Lamata
- Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
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Martinez-Navarro H, Zhou X, Bueno-Orovio A, Rodriguez B. Electrophysiological and anatomical factors determine arrhythmic risk in acute myocardial ischaemia and its modulation by sodium current availability. Interface Focus 2020; 11:20190124. [PMID: 33335705 PMCID: PMC7739909 DOI: 10.1098/rsfs.2019.0124] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2020] [Indexed: 12/12/2022] Open
Abstract
Acute myocardial ischaemia caused by coronary artery disease is one of the main causes of sudden cardiac death. Even though sodium current blockers are used as anti-arrhythmic drugs, decreased sodium current availability, also caused by mutations, has been shown to increase arrhythmic risk in ischaemic patients. The mechanisms are still unclear. Our goal is to exploit perfect control and data transparency of over 300 high-performance computing simulations to investigate arrhythmia mechanisms in acute myocardial ischaemia with variable sodium current availability. The human anatomically based torso-biventricular electrophysiological model used includes representation of realistic ventricular anatomy and fibre architecture, as well as ionic to electrocardiographic properties. Simulations show that reduced sodium current availability increased arrhythmic risk in acute regional ischaemia due to both electrophysiological (increased dispersion of refractoriness across the ischaemic border zone) and anatomical factors (conduction block from the thin right ventricle to thick left ventricle). The asymmetric ventricular anatomy caused high arrhythmic risk specifically for ectopic stimuli originating from the right ventricle and ventricular base. Increased sodium current availability was ineffective in reducing arrhythmic risk for septo-basal ectopic excitation. Human-based multiscale modelling and simulations reveal key electrophysiological and anatomical factors determining arrhythmic risk in acute ischaemia with variable sodium current availability.
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Affiliation(s)
- Hector Martinez-Navarro
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Parks Road, Oxford OX1 3QD, UK
| | - Xin Zhou
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Parks Road, Oxford OX1 3QD, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Parks Road, Oxford OX1 3QD, UK
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Parks Road, Oxford OX1 3QD, UK
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Margara F, Passini E, Levrero-Florencio F, Bueno-Orovio A, Rodriguez B. Simultaneous assessment of drug-induced effects on contractility and electrophysiology using human in silico trials. J Pharmacol Toxicol Methods 2020. [DOI: 10.1016/j.vascn.2020.106803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Passini E, Tomek J, Zhou X, Bueno-Orovio A, Rodriguez B. Human in silico drug trials with a novel human ventricular electrophysiology model. J Pharmacol Toxicol Methods 2020. [DOI: 10.1016/j.vascn.2020.106805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Mamoshina P, Bueno-Orovio A, Rodriguez B. Dual Transcriptomic and Molecular Machine Learning Predicts all Major Clinical Forms of Drug Cardiotoxicity. Front Pharmacol 2020; 11:639. [PMID: 32508633 PMCID: PMC7253645 DOI: 10.3389/fphar.2020.00639] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 04/21/2020] [Indexed: 11/13/2022] Open
Abstract
Computational methods can increase productivity of drug discovery pipelines, through overcoming challenges such as cardiotoxicity identification. We demonstrate prediction and preservation of cardiotoxic relationships for six drug-induced cardiotoxicity types using a machine learning approach on a large collected and curated dataset of transcriptional and molecular profiles (1,131 drugs, 35% with known cardiotoxicities, and 9,933 samples). The algorithm generality is demonstrated through validation in an independent drug dataset, in addition to cross-validation. The best prediction attains an average accuracy of 79% in area under the curve (AUC) for safe versus risky drugs, across all six cardiotoxicity types on validation and 66% on the unseen set of drugs. Individual cardiotoxicities for specific drug types are also predicted with high accuracy, including cardiac disorder signs and symptoms for a previously unseen set of anti-inflammatory agents (AUC = 80%) and heart failures for an unseen set of anti-neoplastic agents (AUC = 76%). Besides, independent testing on transcriptional data from the Drug Toxicity Signature Generation Center (DToxS) produces similar results in terms of accuracy and shows an average AUC of 72% for previously seen drugs and 60% for unseen respectively. Given the ubiquitous manifestation of multiple drug adverse effects in every human organ, the methodology is expected to be applicable to additional tissue-specific side effects beyond cardiotoxicity.
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Affiliation(s)
- Polina Mamoshina
- Department of Computer Science, University of Oxford, Oxford, United Kingdom.,Insilico Medicine Hong Kong Ltd, Hong Kong, Hong Kong
| | | | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
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Levrero-Florencio F, Margara F, Zacur E, Bueno-Orovio A, Wang Z, Santiago A, Aguado-Sierra J, Houzeaux G, Grau V, Kay D, Vázquez M, Ruiz-Baier R, Rodriguez B. Sensitivity analysis of a strongly-coupled human-based electromechanical cardiac model: Effect of mechanical parameters on physiologically relevant biomarkers. Comput Methods Appl Mech Eng 2020; 361:112762. [PMID: 32565583 PMCID: PMC7299076 DOI: 10.1016/j.cma.2019.112762] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The human heart beats as a result of multiscale nonlinear dynamics coupling subcellular to whole organ processes, achieving electrophysiologically-driven mechanical contraction. Computational cardiac modelling and simulation have achieved a great degree of maturity, both in terms of mathematical models of underlying biophysical processes and the development of simulation software. In this study, we present the detailed description of a human-based physiologically-based, and fully-coupled ventricular electromechanical modelling and simulation framework, and a sensitivity analysis focused on its mechanical properties. The biophysical detail of the model, from ionic to whole-organ, is crucial to enable future simulations of disease and drug action. Key novelties include the coupling of state-of-the-art human-based electrophysiology membrane kinetics, excitation-contraction and active contraction models, and the incorporation of a pre-stress model to allow for pre-stressing and pre-loading the ventricles in a dynamical regime. Through high performance computing simulations, we demonstrate that 50% to 200% - 1000% variations in key parameters result in changes in clinically-relevant mechanical biomarkers ranging from diseased to healthy values in clinical studies. Furthermore mechanical biomarkers are primarily affected by only one or two parameters. Specifically, ejection fraction is dominated by the scaling parameter of the active tension model and its scaling parameter in the normal direction ( k ort 2 ); the end systolic pressure is dominated by the pressure at which the ejection phase is triggered ( P ej ) and the compliance of the Windkessel fluid model ( C ); and the longitudinal fractional shortening is dominated by the fibre angle ( ϕ ) and k ort 2 . The wall thickening does not seem to be clearly dominated by any of the considered input parameters. In summary, this study presents in detail the description and implementation of a human-based coupled electromechanical modelling and simulation framework, and a high performance computing study on the sensitivity of mechanical biomarkers to key model parameters. The tools and knowledge generated enable future investigations into disease and drug action on human ventricles.
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Affiliation(s)
- F. Levrero-Florencio
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
- Corresponding authors.
| | - F. Margara
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
| | - E. Zacur
- Department of Engineering Science, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - A. Bueno-Orovio
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
| | - Z.J. Wang
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
| | - A. Santiago
- Barcelona Supercomputing Center – Centro Nacional de Supercomputación, Barcelona 08034, Spain
| | - J. Aguado-Sierra
- Barcelona Supercomputing Center – Centro Nacional de Supercomputación, Barcelona 08034, Spain
| | - G. Houzeaux
- Barcelona Supercomputing Center – Centro Nacional de Supercomputación, Barcelona 08034, Spain
| | - V. Grau
- Department of Engineering Science, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - D. Kay
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
| | - M. Vázquez
- Barcelona Supercomputing Center – Centro Nacional de Supercomputación, Barcelona 08034, Spain
- ELEM Biotech, Spain
| | - R. Ruiz-Baier
- Mathematical Institute, University of Oxford, Oxford OX2 6GG, United Kingdom
- Universidad Adventista de Chile, Casilla 7-D, Chillan, Chile
| | - B. Rodriguez
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom
- Corresponding authors.
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29
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Cooper FR, Baker RE, Bernabeu MO, Bordas R, Bowler L, Bueno-Orovio A, Byrne HM, Carapella V, Cardone-Noott L, Jonatha C, Dutta S, Evans BD, Fletcher AG, Grogan JA, Guo W, Harvey DG, Hendrix M, Kay D, Kursawe J, Maini PK, McMillan B, Mirams GR, Osborne JM, Pathmanathan P, Pitt-Francis JM, Robinson M, Rodriguez B, Spiteri RJ, Gavaghan DJ. Chaste: Cancer, Heart and Soft Tissue Environment. J Open Source Softw 2020; 5:1848. [PMID: 37192932 PMCID: PMC7614534 DOI: 10.21105/joss.01848] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Chaste (Cancer, Heart And Soft Tissue Environment) is an open source simulation package for the numerical solution of mathematical models arising in physiology and biology. To date, Chaste development has been driven primarily by applications that include continuum modelling of cardiac electrophysiology ('Cardiac Chaste'), discrete cell-based modelling of soft tissues ('Cell-based Chaste'), and modelling of ventilation in lungs ('Lung Chaste'). Cardiac Chaste addresses the need for a high-performance, generic, and verified simulation framework for cardiac electrophysiology that is freely available to the scientific community. Cardiac chaste provides a software package capable of realistic heart simulations that is efficient, rigorously tested, and runs on HPC platforms. Cell-based Chaste addresses the need for efficient and verified implementations of cell-based modelling frameworks, providing a set of extensible tools for simulating biological tissues. Computational modelling, along with live imaging techniques, plays an important role in understanding the processes of tissue growth and repair. A wide range of cell-based modelling frameworks have been developed that have each been successfully applied in a range of biological applications. Cell-based Chaste includes implementations of the cellular automaton model, the cellular Potts model, cell-centre models with cell representations as overlapping spheres or Voronoi tessellations, and the vertex model. Lung Chaste addresses the need for a novel, generic and efficient lung modelling software package that is both tested and verified. It aims to couple biophysically-detailed models of airway mechanics with organ-scale ventilation models in a package that is freely available to the scientific community. Chaste is designed to be modular and extensible, providing libraries for common scientific computing infrastructure such as linear algebra operations, finite element meshes, and ordinary and partial differential equation solvers. This infrastructure is used by libraries for specific applications, such as continuum mechanics, cardiac models, and cell-based models. The software engineering techniques used to develop Chaste are intended to ensure code quality, re-usability and reliability. Primary applications of the software include cardiac and respiratory physiology, cancer and developmental biology.
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Affiliation(s)
- Fergus R Cooper
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, UK
| | - Ruth E Baker
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, UK
| | - Miguel O Bernabeu
- Centre for Medical Informatics, Usher Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Rafel Bordas
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Louise Bowler
- Department of Computer Science, University of Oxford, Oxford, UK
| | | | - Helen M Byrne
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, UK
| | - Valentina Carapella
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Cooper Jonatha
- Research IT Services, University College London, London, UK
| | - Sara Dutta
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Benjamin D Evans
- Centre for Biomedical Modelling and Analysis, Living Systems Institute, University of Exeter, Exeter, UK
- School of Psychological Science, University of Bristol, Bristol, UK
| | - Alexander G Fletcher
- School of Mathematics & Statistics, University of Sheffield, Sheffield, UK
- Bateson Centre, University of Sheffield, Sheffield, UK
| | - James A Grogan
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, UK
| | - Wenxian Guo
- Department of Computer Science, University of Saskatchewan, Canada
| | - Daniel G Harvey
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Maurice Hendrix
- Centre for Mathematical Medicine & Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK
- Digital Research Service, University of Nottingham, Nottingham, UK
| | - David Kay
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Jochen Kursawe
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Philip K Maini
- Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford, UK
| | - Beth McMillan
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Gary R Mirams
- Centre for Mathematical Medicine & Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, UK
| | - James M Osborne
- School of Mathematics and Statistics, University of Melbourne, Victoria, Australia
| | - Pras Pathmanathan
- Office of Science and Engineering Laboratories (OSEL), Center for Devices and Radiological Health (CDRH), U.S. Food and Drug Administration (FDA), Silver Spring, MD 20993, USA
| | | | - Martin Robinson
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, UK
| | | | - David J Gavaghan
- Department of Computer Science, University of Oxford, Oxford, UK
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30
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Zhou X, Qu Y, Passini E, Bueno-Orovio A, Liu Y, Vargas HM, Rodriguez B. Blinded In Silico Drug Trial Reveals the Minimum Set of Ion Channels for Torsades de Pointes Risk Assessment. Front Pharmacol 2020; 10:1643. [PMID: 32082155 PMCID: PMC7003137 DOI: 10.3389/fphar.2019.01643] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022] Open
Abstract
Torsades de Pointes (TdP) is a type of ventricular arrhythmia which could be observed as an unwanted drug-induced cardiac side effect, and it is associated with repolarization abnormalities in single cells. The pharmacological evaluations of TdP risk in previous years mainly focused on the hERG channel due to its vital role in the repolarization of cardiomyocytes. However, only considering drug effects on hERG led to false positive predictions since the drug action on other ion channels can also have crucial regulatory effects on repolarization. To address the limitation of only evaluating hERG, the Comprehensive in Vitro Proarrhythmia Assay initiative has proposed to systematically integrate drug effects on multiple ion channels into in silico drug trial to improve TdP risk assessment. It is not clear how many ion channels are sufficient for reliable TdP risk predictions, and whether differences in IC50 and Hill coefficient values from independent sources can lead to divergent in silico prediction outcomes. The rationale of this work is to investigate the above two questions using a computationally efficient population of human ventricular cells optimized to favor repolarization abnormality. Our blinded results based on two independent data sources confirm that simulations with the optimized population of human ventricular cell models enable efficient in silico drug screening, and also provide direct observation and mechanistic analysis of repolarization abnormality. Our results show that 1) the minimum set of ion channels required for reliable TdP risk predictions are Nav1.5 (peak), Cav1.2, and hERG; 2) for drugs with multiple ion channel blockage effects, moderate IC50 variations combined with variable Hill coefficients can affect the accuracy of in silico predictions.
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Affiliation(s)
- Xin Zhou
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Yusheng Qu
- SPARC, Amgen Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Elisa Passini
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Alfonso Bueno-Orovio
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Yang Liu
- GAU, Amgen Research, Amgen Inc., South San Francisco, CA, United States
| | - Hugo M Vargas
- SPARC, Amgen Research, Amgen Inc., Thousand Oaks, CA, United States
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
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31
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Tomek J, Bueno-Orovio A, Passini E, Zhou X, Minchole A, Britton O, Bartolucci C, Severi S, Shrier A, Virag L, Varro A, Rodriguez B. Development, calibration, and validation of a novel human ventricular myocyte model in health, disease, and drug block. eLife 2019; 8:48890. [PMID: 31868580 PMCID: PMC6970534 DOI: 10.7554/elife.48890] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 12/18/2019] [Indexed: 12/19/2022] Open
Abstract
Human-based modelling and simulations are becoming ubiquitous in biomedical science due to their ability to augment experimental and clinical investigations. Cardiac electrophysiology is one of the most advanced areas, with cardiac modelling and simulation being considered for virtual testing of pharmacological therapies and medical devices. Current models present inconsistencies with experimental data, which limit further progress. In this study, we present the design, development, calibration and independent validation of a human-based ventricular model (ToR-ORd) for simulations of electrophysiology and excitation-contraction coupling, from ionic to whole-organ dynamics, including the electrocardiogram. Validation based on substantial multiscale simulations supports the credibility of the ToR-ORd model under healthy and key disease conditions, as well as drug blockade. In addition, the process uncovers new theoretical insights into the biophysical properties of the L-type calcium current, which are critical for sodium and calcium dynamics. These insights enable the reformulation of L-type calcium current, as well as replacement of the hERG current model.
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Affiliation(s)
- Jakub Tomek
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Alfonso Bueno-Orovio
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Elisa Passini
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Xin Zhou
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Ana Minchole
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Oliver Britton
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Chiara Bartolucci
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Bologna, Italy
| | - Stefano Severi
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Bologna, Italy
| | - Alvin Shrier
- Department of Physiology, McGill University, Montreal, Canada
| | - Laszlo Virag
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Andras Varro
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
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32
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Coppini R, Ferrantini C, Pioner JM, Santini L, Wang ZJ, Palandri C, Scardigli M, Vitale G, Sacconi L, Stefàno P, Flink L, Riedy K, Pavone FS, Cerbai E, Poggesi C, Mugelli A, Bueno-Orovio A, Olivotto I, Sherrid MV. Electrophysiological and Contractile Effects of Disopyramide in Patients With Obstructive Hypertrophic Cardiomyopathy: A Translational Study. JACC Basic Transl Sci 2019; 4:795-813. [PMID: 31998849 PMCID: PMC6978554 DOI: 10.1016/j.jacbts.2019.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/07/2019] [Accepted: 06/07/2019] [Indexed: 01/26/2023]
Abstract
In patients with HCM and symptomatic LVOT-obstruction, first treatment with disopyramide leads to a marked reduction of LVOT gradients, with a slight decrease of resting ejection fraction and a modest increase of corrected QT interval, highlighting high efficacy and safety. In single cardiomyocytes and intact trabeculae from surgical samples of patients with obstructive HCM, in vitro treatment with 5 μmol/l disopyramide lowered force and Ca2+ transients while reducing action potential duration and the rate of arrhythmic afterdepolarizations. These effects are mediated by the combined inhibition of peak and late Na+ currents, L-type Ca2+ current, delayed-rectifier K+ current, and ryanodine receptors. In addition to the negative inotropic effect of disopyramide, in vitro results suggest additional antiarrhythmic actions.
Disopyramide is effective and safe in patients with obstructive hypertrophic cardiomyopathy. However, its cellular and molecular mechanisms of action are unknown. We tested disopyramide in cardiomyocytes from the septum of surgical myectomy patients: disopyramide inhibits multiple ion channels, leading to lower Ca transients and force, and shortens action potentials, thus reducing cellular arrhythmias. The electrophysiological profile of disopyramide explains the efficient reduction of outflow gradients but also the limited prolongation of the QT interval and the absence of arrhythmic side effects observed in 39 disopyramide-treated patients. In conclusion, our results support the idea that disopyramide is safe for outpatient use in obstructive patients.
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Key Words
- AP, action potential
- DAD, delayed afterdepolarization
- EAD, early afterdepolarization
- ECG, electrocardiography
- HCM, hypertrophic cardiomyopathy
- ICa-L, L-type Ca current
- IK, delayed-rectifier K current
- INaL, late Na current
- LVOT, left ventricular outflow tract
- NCX, Na+/Ca2+ exchanger
- QT interval
- RyR, ryanodine receptor
- SR, sarcoplasmic reticulum
- action potentials
- arrhythmias
- diastolic dysfunction
- hERG, human ether-à-go-go-related gene
- hypertrophic cardiomyopathy
- pCa, Ca activation level
- safety
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Affiliation(s)
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Josè Manuel Pioner
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Lorenzo Santini
- Department NeuroFarBa, University of Florence, Florence, Italy
| | - Zhinuo J Wang
- Department of Computer Sciences, University of Oxford, Oxford, United Kingdom
| | - Chiara Palandri
- Department NeuroFarBa, University of Florence, Florence, Italy
| | - Marina Scardigli
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Leonardo Sacconi
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | - Pierluigi Stefàno
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Laura Flink
- Division of Cardiology, San Francisco Veterans Affairs Medical Center and University of California-San Francisco, San Francisco, California
| | - Katherine Riedy
- Hypertrophic Cardiomyopathy Program, New York University Langone Health, New York, New York
| | - Francesco Saverio Pavone
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | | | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | | | | | - Iacopo Olivotto
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Mark V Sherrid
- Hypertrophic Cardiomyopathy Program, New York University Langone Health, New York, New York
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33
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Lyon A, Mincholé A, Bueno-Orovio A, Rodriguez B. Improving the clinical understanding of hypertrophic cardiomyopathy by combining patient data, machine learning and computer simulations: A case study. Morphologie 2019; 103:169-179. [PMID: 31570308 PMCID: PMC6913520 DOI: 10.1016/j.morpho.2019.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 01/02/2023]
Abstract
In this paper, we present how, by combining electrocardiogram and imaging data, machine learning and high performance computing simulations, we identified four phenotypes in hypertrophic cardiomyopathy (HCM), with differences in arrhythmic risk, and provided two distinct possible mechanisms that may explain the heterogeneity of HCM manifestation. This led to a better HCM patient stratification and understanding of the underlying disease mechanisms, providing a step further towards tailored HCM patient management and treatment.
Most patients with hypertrophic cardiomyopathy (HCM), the most common genetic cardiac disease, remain asymptomatic, but others may suffer from sudden cardiac death. A better identification of those patients at risk, together with a better understanding of the mechanisms leading to arrhythmia, are crucial to target high-risk patients and provide them with appropriate treatment. However, this currently remains a challenge. In this paper, we present a successful example of implementing computational techniques for clinically-relevant applications. By combining electrocardiogram and imaging data, machine learning and high performance computing simulations, we identified four phenotypes in HCM, with differences in arrhythmic risk, and provided two distinct possible mechanisms that may explain the heterogeneity of HCM manifestation. This led to a better HCM patient stratification and understanding of the underlying disease mechanisms, providing a step further towards tailored HCM patient management and treatment.
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Affiliation(s)
- A Lyon
- Department of Computer Science, University of Oxford, Oxford, United Kingdom; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - A Mincholé
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - A Bueno-Orovio
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - B Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom.
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Passini E, Trovato C, Morissette P, Sannajust F, Bueno-Orovio A, Rodriguez B. Drug-induced shortening of the electromechanical window is an effective biomarker for in silico prediction of clinical risk of arrhythmias. Br J Pharmacol 2019; 176:3819-3833. [PMID: 31271649 PMCID: PMC6780030 DOI: 10.1111/bph.14786] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 05/21/2019] [Accepted: 06/28/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE Early identification of drug-induced cardiac adverse events is key in drug development. Human-based computer models are emerging as an effective approach, complementary to in vitro and animal models. Drug-induced shortening of the electromechanical window has been associated with increased risk of arrhythmias. This study investigates the potential of a cellular surrogate for the electromechanical window (EMw) for prediction of pro-arrhythmic cardiotoxicity, and its underlying ionic mechanisms, using human-based computer models. EXPERIMENTAL APPROACH In silico drug trials for 40 reference compounds were performed, testing up to 100-fold the therapeutic concentrations (EFTPCmax ) and using a control population of human ventricular action potential (AP) models, optimised to capture pro-arrhythmic ionic profiles. EMw was calculated for each model in the population as the difference between AP and Ca2+ transient durations at 90%. Drug-induced changes in the EMw and occurrence of repolarisation abnormalities (RA) were quantified. KEY RESULTS Drugs with clinical risk of Torsade de Pointes arrhythmias induced a concentration-dependent EMw shortening, while safe drugs lead to increase or small change in EMw. Risk predictions based on EMw shortening achieved 90% accuracy at 10× EFTPCmax , whereas RA-based predictions required 100× EFTPCmax to reach the same accuracy. As it is dependent on Ca2+ transient, the EMw was also more sensitive than AP prolongation in distinguishing between pure hERG blockers and multichannel compounds also blocking the calcium current. CONCLUSION AND IMPLICATIONS The EMw is an effective biomarker for in silico predictions of drug-induced clinical pro-arrhythmic risk, particularly for compounds with multichannel blocking action.
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Affiliation(s)
- Elisa Passini
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Cristian Trovato
- Department of Computer Science, University of Oxford, Oxford, UK
| | - Pierre Morissette
- SALAR, Safety and Exploratory Pharmacology Department, Merck Research Laboratories, Merck & Co., Inc., West Point, PA, USA
| | - Frederick Sannajust
- SALAR, Safety and Exploratory Pharmacology Department, Merck Research Laboratories, Merck & Co., Inc., West Point, PA, USA
| | | | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, UK
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35
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Passini E, Britton OJ, Bueno-Orovio A, Rodriguez B. Human in silico trials on drug-induced changes in electrophysiology and calcium dynamics using the virtual assay software. J Pharmacol Toxicol Methods 2019. [DOI: 10.1016/j.vascn.2019.05.104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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36
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Zhou X, Bueno-Orovio A, Schilling RJ, Kirkby C, Denning C, Rajamohan D, Burrage K, Tinker A, Rodriguez B, Harmer SC. Investigating the Complex Arrhythmic Phenotype Caused by the Gain-of-Function Mutation KCNQ1-G229D. Front Physiol 2019; 10:259. [PMID: 30967788 PMCID: PMC6430739 DOI: 10.3389/fphys.2019.00259] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 02/28/2019] [Indexed: 12/18/2022] Open
Abstract
The congenital long QT syndrome (LQTS) is a cardiac electrophysiological disorder that can cause sudden cardiac death. LQT1 is a subtype of LQTS caused by mutations in KCNQ1, affecting the slow delayed-rectifier potassium current (I Ks), which is essential for cardiac repolarization. Paradoxically, gain-of-function mutations in KCNQ1 have been reported to cause borderline QT prolongation, atrial fibrillation (AF), sinus bradycardia, and sudden death, however, the mechanisms are not well understood. The goal of the study is to investigate the ionic, cellular and tissue mechanisms underlying the complex phenotype of a gain-of-function mutation in KCNQ1, c.686G > A (p.G229D) using computer modeling and simulations informed by in vitro measurements. Previous studies have shown this mutation to cause AF and borderline QT prolongation. We report a clinical description of a family that carry this mutation and that a member of the family died suddenly during sleep at 21 years old. Using patch-clamp experiments, we confirm that KCNQ1-G229D causes a significant gain in channel function. We introduce the effect of the mutation in populations of atrial, ventricular and sinus node (SN) cell models to investigate mechanisms underlying phenotypic variability. In a population of human atrial and ventricular cell models and tissue, the presence of KCNQ1-G229D predominantly shortens atrial action potential duration (APD). However, in a subset of models, KCNQ1-G229D can act to prolong ventricular APD by up to 7% (19 ms) and underlie depolarization abnormalities, which could promote QT prolongation and conduction delays. Interestingly, APD prolongations were predominantly seen at slow pacing cycle lengths (CL > 1,000 ms), which suggests a greater arrhythmic risk during bradycardia, and is consistent with the observed sudden death during sleep. In a population of human SN cell models, the KCNQ1-G229D mutation results in slow/abnormal sinus rhythm, and we identify that a stronger L-type calcium current enables the SN to be more robust to the mutation. In conclusion, our computational modeling experiments provide novel mechanistic explanations for the observed borderline QT prolongation, and predict that KCNQ1-G229D could underlie SN dysfunction and conduction delays. The mechanisms revealed in the study can potentially inform management and treatment of KCNQ1 gain-of-function mutation carriers.
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Affiliation(s)
- Xin Zhou
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Alfonso Bueno-Orovio
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | | | | | - Chris Denning
- Department of Stem Cell Biology, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Divya Rajamohan
- Department of Stem Cell Biology, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Kevin Burrage
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, QLD, Australia
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Andrew Tinker
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Stephen C. Harmer
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
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Corral Acero J, Zacur E, Xu H, Ariga R, Bueno-Orovio A, Lamata P, Grau V. SMOD - Data Augmentation Based on Statistical Models of Deformation to Enhance Segmentation in 2D Cine Cardiac MRI. Functional Imaging and Modeling of the Heart 2019. [DOI: 10.1007/978-3-030-21949-9_39] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Lyon A, Bueno-Orovio A, Zacur E, Ariga R, Grau V, Neubauer S, Watkins H, Rodriguez B, Mincholé A. Electrocardiogram phenotypes in hypertrophic cardiomyopathy caused by distinct mechanisms: apico-basal repolarization gradients vs. Purkinje-myocardial coupling abnormalities. Europace 2018; 20:iii102-iii112. [PMID: 30476051 PMCID: PMC6251182 DOI: 10.1093/europace/euy226] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 09/27/2018] [Indexed: 12/13/2022] Open
Abstract
AIMS To identify key structural and electrophysiological features explaining distinct electrocardiogram (ECG) phenotypes in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS Human heart-torso anatomical models were constructed from cardiac magnetic resonance (CMR) images of HCM patients, representative of ECG phenotypes identified previously. High performance computing simulations using bidomain models were conducted to dissect key features explaining the ECG phenotypes with increased HCM Risk-SCD scores, namely Group 1A, characterized by normal QRS but inverted T waves laterally and coexistence of apical and septal hypertrophy; and Group 3 with marked QRS abnormalities (deep and wide S waves laterally) and septal hypertrophy. Hypertrophic cardiomyopathy abnormalities characterized from CMR, such as hypertrophy, tissue microstructure alterations, abnormal conduction system, and ionic remodelling, were selectively included to assess their influence on ECG morphology. Electrocardiogram abnormalities could not be explained by increased wall thickness nor by local conduction abnormalities associated with fibre disarray or fibrosis. Inverted T wave with normal QRS (Group 1A) was obtained with increased apico-basal repolarization gradient caused by ionic remodelling in septum and apex. Lateral QRS abnormalities (Group 3) were only recovered with abnormal Purkinje-myocardium coupling. CONCLUSION Two ECG-based HCM phenotypes are explained by distinct mechanisms: ionic remodelling and action potential prolongation in hypertrophied apical and septal areas lead to T wave inversion with normal QRS complexes, whereas abnormal Purkinje-myocardial coupling causes abnormal QRS morphology in V4-V6. These findings have potential implications for patients' management as they point towards different arrhythmia mechanisms in different phenotypes.
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Affiliation(s)
- Aurore Lyon
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
| | - Ernesto Zacur
- Institute of Biomedical Engineering (IBME), Department of Engineering Science, University of Oxford, Oxford, UK
| | - Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Vicente Grau
- Institute of Biomedical Engineering (IBME), Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
- Corresponding author. Tel: +44 1865 610806; fax: 00441865273839. E-mail address:
| | - Ana Mincholé
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd, Oxford, UK
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Bueno-Orovio A. Commentary: Atrial Rotor Dynamics Under Complex Fractional Order Diffusion. Front Physiol 2018; 9:1386. [PMID: 30337882 PMCID: PMC6180174 DOI: 10.3389/fphys.2018.01386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 09/11/2018] [Indexed: 11/24/2022] Open
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Passini E, Britton OJ, Greig RJ, Bueno-Orovio A, Rodriguez B. Virtual assay: A user-friendly framework for in silico drug trials in populations of human cardiomyocyte models. J Pharmacol Toxicol Methods 2018. [DOI: 10.1016/j.vascn.2018.01.481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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41
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Lawson BA, Burrage K, Burrage P, Drovandi CC, Bueno-Orovio A. Slow Recovery of Excitability Increases Ventricular Fibrillation Risk as Identified by Emulation. Front Physiol 2018; 9:1114. [PMID: 30210355 PMCID: PMC6121112 DOI: 10.3389/fphys.2018.01114] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 07/25/2018] [Indexed: 12/28/2022] Open
Abstract
Purpose: Rotor stability and meandering are key mechanisms determining and sustaining cardiac fibrillation, with important implications for anti-arrhythmic drug development. However, little is yet known on how rotor dynamics are modulated by variability in cellular electrophysiology, particularly on kinetic properties of ion channel recovery. Methods: We propose a novel emulation approach, based on Gaussian process regression augmented with machine learning, for data enrichment, automatic detection, classification, and analysis of re-entrant biomarkers in cardiac tissue. More than 5,000 monodomain simulations of long-lasting arrhythmic episodes with Fenton-Karma ionic dynamics, further enriched by emulation to 80 million electrophysiological scenarios, were conducted to investigate the role of variability in ion channel densities and kinetics in modulating rotor-driven arrhythmic behavior. Results: Our methods predicted the class of excitation behavior with classification accuracy up to 96%, and emulation effectively predicted frequency, stability, and spatial biomarkers of functional re-entry. We demonstrate that the excitation wavelength interpretation of re-entrant behavior hides critical information about rotor persistence and devolution into fibrillation. In particular, whereas action potential duration directly modulates rotor frequency and meandering, critical windows of excitability are identified as the main determinants of breakup. Further novel electrophysiological insights of particular relevance for ventricular arrhythmias arise from our multivariate analysis, including the role of incomplete activation of slow inward currents in mediating tissue rate-dependence and dispersion of repolarization, and the emergence of slow recovery of excitability as a significant promoter of this mechanism of dispersion and increased arrhythmic risk. Conclusions: Our results mechanistically explain pro-arrhythmic effects of class Ic anti-arrhythmics in the ventricles despite their established role in the pharmacological management of atrial fibrillation. This is mediated by their slow recovery of excitability mode of action, promoting incomplete activation of slow inward currents and therefore increased dispersion of repolarization, given the larger influence of these currents in modulating the action potential in the ventricles compared to the atria. These results exemplify the potential of emulation techniques in elucidating novel mechanisms of arrhythmia and further application to cardiac electrophysiology.
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Affiliation(s)
- Brodie A Lawson
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Kevin Burrage
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia.,Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Pamela Burrage
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Christopher C Drovandi
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
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Cardone-Noott L, Rodriguez B, Bueno-Orovio A. Strategies of data layout and cache writing for input-output optimization in high performance scientific computing: Applications to the forward electrocardiographic problem. PLoS One 2018; 13:e0202410. [PMID: 30138401 PMCID: PMC6107169 DOI: 10.1371/journal.pone.0202410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 08/02/2018] [Indexed: 11/19/2022] Open
Abstract
Input-output (I/O) optimization at the low-level design of data layout on disk drastically impacts the efficiency of high performance computing (HPC) applications. However, such a low-level optimization is in general challenging, especially when using popular scientific file formats designed with an emphasis on portability and flexibility. To reconcile these two aspects, we present a novel low-level data layout for HPC applications, fully independent of the number of dimensions in the dataset. The new data layout improves reading and writing efficiency in large HPC applications using many processors, and in particular during parallel post-processing. Furthermore, its combination with a cached write mode, in order to aggregate multiple writes into larger ones, substantially decreased the writing times of the proposed strategy. When applied to our simulation framework for the forward calculation of the human electrocardiogram, the combined strategy resulted in drastic improvements in I/O performance, of up to 40% in writing and 93–98% in reading for post-processing tasks. Given the generality of the proposed strategies and scientific file formats used, our results may represent significant improvements in I/O performance of HPC applications across multiple disciplines, reducing execution and post-processing times and leading to a more efficient use of HPC resource envelopes.
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Affiliation(s)
- Louie Cardone-Noott
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Liberos A, Hernandez-Romero I, De La Nava AS, Rodrigo M, Bueno-Orovio A, Rodriguez B, Guillem MS, Atienza F, Climent AM, Fernandez-Aviles F. P503Inter-subject variability explains juxtaposed effects in pharmacological treatments: an in-silico approach for the personalization of atrial fibrillation drug treatments. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- A Liberos
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
| | - I Hernandez-Romero
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
| | - A S De La Nava
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
| | - M Rodrigo
- Universitat Politècnica de València, ITACA, València, Spain
| | - A Bueno-Orovio
- University of Oxford, Department of Computer Science, Oxford, United Kingdom
| | - B Rodriguez
- University of Oxford, Department of Computer Science, Oxford, United Kingdom
| | - M S Guillem
- Universitat Politècnica de València, ITACA, València, Spain
| | - F Atienza
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
| | - A M Climent
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
| | - F Fernandez-Aviles
- Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain
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Hanson BM, Gill JS, Taggart P, Rodriguez B, Bueno-Orovio A. Slow Adaptation of Ventricular Repolarization as a Cause of Arrhythmia? Methods Inf Med 2018; 53:320-3. [DOI: 10.3414/me13-02-0039] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 02/12/2014] [Indexed: 11/09/2022]
Abstract
SummaryIntroduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems”.Background: Adaptation of the QT-interval to changes in heart rate reflects on the body-surface electrocardiogram the adaptation of action potential duration (APD) at the cellular level. The initial fast phase of APD adaptation has been shown to modulate the arrhythmia substrate. Whether the slow phase is potentially proarrhythmic remains unclear.Objectives: To analyze in-vivo human data and use computer simulations to examine effects of the slow APD adaptation phase on dispersion of repolarization and reentry in the human ventricle.Methods: Electrograms were acquired from 10 left and 10 right ventricle (LV/RV) endocardial sites in 15 patients with normal ventricles during RV pacing. Activation-recovery intervals, as a surrogate for APD, were measured during a sustained increase in heart rate. Observed dynamics were studied using computer simulations of human tissue electrophysiology.Results: Spatial heterogeneity of rate adaptation was observed in all patients. Inhomogeneity in slow APD adaptation time constants (ΔTs) was greater in LV than RV (ΔTs LV = 31.8 ± 13.2, ΔTs RV = 19.0 ± 12.8 s, P < 0.01). Simulations showed that altering local slow time constants of adaptation was sufficient to convert partial wavefront block to block with successful reentry.Conclusions: Using electrophysiological data acquired in-vivo in human and computer simulations, we identify heterogeneity in the slow phase of APD adaptation as an important component of arrhythmogenesis.
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Muszkiewicz A, Liu X, Bueno-Orovio A, Lawson BAJ, Burrage K, Casadei B, Rodriguez B. From ionic to cellular variability in human atrial myocytes: an integrative computational and experimental study. Am J Physiol Heart Circ Physiol 2017; 314:H895-H916. [PMID: 29351467 PMCID: PMC6008144 DOI: 10.1152/ajpheart.00477.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Variability refers to differences in physiological function between individuals, which may translate into different disease susceptibility and treatment efficacy. Experiments in human cardiomyocytes face wide variability and restricted tissue access; under these conditions, computational models are a useful complementary tool. We conducted a computational and experimental investigation in cardiomyocytes isolated from samples of the right atrial appendage of patients undergoing cardiac surgery to evaluate the impact of variability in action potentials (APs) and subcellular ionic densities on Ca2+ transient dynamics. Results showed that 1) variability in APs and ionic densities is large, even within an apparently homogenous patient cohort, and translates into ±100% variation in ionic conductances; 2) experimentally calibrated populations of models with wide variations in ionic densities yield APs overlapping with those obtained experimentally, even if AP characteristics of the original generic model differed significantly from experimental APs; 3) model calibration with AP recordings restricts the variability in ionic densities affecting upstroke and resting potential, but redundancy in repolarization currents admits substantial variability in ionic densities; and 4) model populations constrained with experimental APs and ionic densities exhibit three Ca2+ transient phenotypes, differing in intracellular Ca2+ handling and Na+/Ca2+ membrane extrusion. These findings advance our understanding of the impact of variability in human atrial electrophysiology. NEW & NOTEWORTHY Variability in human atrial electrophysiology is investigated by integrating for the first time cellular-level and ion channel recordings in computational electrophysiological models. Ion channel calibration restricts current densities but not cellular phenotypic variability. Reduced Na+/Ca2+ exchanger is identified as a primary mechanism underlying diastolic Ca2+ fluctuations in human atrial myocytes.
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Affiliation(s)
- Anna Muszkiewicz
- Department of Computer Science, University of Oxford , Oxford , United Kingdom
| | - Xing Liu
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital , Oxford , United Kingdom
| | | | - Brodie A J Lawson
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology , Brisbane, Queensland , Australia.,School of Mathematics, Queensland University of Technology , Brisbane, Queensland , Australia
| | - Kevin Burrage
- Department of Computer Science, University of Oxford , Oxford , United Kingdom.,ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology , Brisbane, Queensland , Australia.,School of Mathematics, Queensland University of Technology , Brisbane, Queensland , Australia
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital , Oxford , United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford , Oxford , United Kingdom
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Britton OJ, Bueno-Orovio A, Virág L, Varró A, Rodriguez B. Corrigendum: The Electrogenic Na +/K + Pump Is a Key Determinant of Repolarization Abnormality Susceptibility in Human Ventricular Cardiomyocytes: A Population-Based Simulation Study. Front Physiol 2017; 8:954. [PMID: 29167647 PMCID: PMC5698266 DOI: 10.3389/fphys.2017.00954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 11/08/2017] [Indexed: 11/13/2022] Open
Abstract
[This corrects the article on p. 278 in vol. 8, PMID: 28529489.].
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Affiliation(s)
- Oliver J. Britton
- Department of Computer Science, University of Oxford, Oxford, United Kingdom,*Correspondence: Oliver J. Britton
| | | | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
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Passini E, Britton O, Bueno-Orovio A, Rodriguez B. In Silico Drug Trials with Virtual Assay Software Predict Drug Cardiotoxicity and Identify Sub-Populations at Higher Risk. J Pharmacol Toxicol Methods 2017. [DOI: 10.1016/j.vascn.2017.09.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Passini E, Britton OJ, Lu HR, Rohrbacher J, Hermans AN, Gallacher DJ, Greig RJH, Bueno-Orovio A, Rodriguez B. Human In Silico Drug Trials Demonstrate Higher Accuracy than Animal Models in Predicting Clinical Pro-Arrhythmic Cardiotoxicity. Front Physiol 2017; 8:668. [PMID: 28955244 PMCID: PMC5601077 DOI: 10.3389/fphys.2017.00668] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 08/23/2017] [Indexed: 01/08/2023] Open
Abstract
Early prediction of cardiotoxicity is critical for drug development. Current animal models raise ethical and translational questions, and have limited accuracy in clinical risk prediction. Human-based computer models constitute a fast, cheap and potentially effective alternative to experimental assays, also facilitating translation to human. Key challenges include consideration of inter-cellular variability in drug responses and integration of computational and experimental methods in safety pharmacology. Our aim is to evaluate the ability of in silico drug trials in populations of human action potential (AP) models to predict clinical risk of drug-induced arrhythmias based on ion channel information, and to compare simulation results against experimental assays commonly used for drug testing. A control population of 1,213 human ventricular AP models in agreement with experimental recordings was constructed. In silico drug trials were performed for 62 reference compounds at multiple concentrations, using pore-block drug models (IC50/Hill coefficient). Drug-induced changes in AP biomarkers were quantified, together with occurrence of repolarization/depolarization abnormalities. Simulation results were used to predict clinical risk based on reports of Torsade de Pointes arrhythmias, and further evaluated in a subset of compounds through comparison with electrocardiograms from rabbit wedge preparations and Ca2+-transient recordings in human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). Drug-induced changes in silico vary in magnitude depending on the specific ionic profile of each model in the population, thus allowing to identify cell sub-populations at higher risk of developing abnormal AP phenotypes. Models with low repolarization reserve (increased Ca2+/late Na+ currents and Na+/Ca2+-exchanger, reduced Na+/K+-pump) are highly vulnerable to drug-induced repolarization abnormalities, while those with reduced inward current density (fast/late Na+ and Ca2+ currents) exhibit high susceptibility to depolarization abnormalities. Repolarization abnormalities in silico predict clinical risk for all compounds with 89% accuracy. Drug-induced changes in biomarkers are in overall agreement across different assays: in silico AP duration changes reflect the ones observed in rabbit QT interval and hiPS-CMs Ca2+-transient, and simulated upstroke velocity captures variations in rabbit QRS complex. Our results demonstrate that human in silico drug trials constitute a powerful methodology for prediction of clinical pro-arrhythmic cardiotoxicity, ready for integration in the existing drug safety assessment pipelines.
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Affiliation(s)
- Elisa Passini
- Computational Cardiovascular Science Group, Department of Computer Science, University of OxfordOxford, United Kingdom
| | - Oliver J Britton
- Computational Cardiovascular Science Group, Department of Computer Science, University of OxfordOxford, United Kingdom
| | - Hua Rong Lu
- Global Safety, Pharmacology, Discovery Sciences, Janssen Research and Development, Janssen Pharmaceutica NVBeerse, Belgium
| | - Jutta Rohrbacher
- Global Safety, Pharmacology, Discovery Sciences, Janssen Research and Development, Janssen Pharmaceutica NVBeerse, Belgium
| | - An N Hermans
- Global Safety, Pharmacology, Discovery Sciences, Janssen Research and Development, Janssen Pharmaceutica NVBeerse, Belgium
| | - David J Gallacher
- Global Safety, Pharmacology, Discovery Sciences, Janssen Research and Development, Janssen Pharmaceutica NVBeerse, Belgium
| | | | - Alfonso Bueno-Orovio
- Computational Cardiovascular Science Group, Department of Computer Science, University of OxfordOxford, United Kingdom
| | - Blanca Rodriguez
- Computational Cardiovascular Science Group, Department of Computer Science, University of OxfordOxford, United Kingdom
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Cardone-Noott L, Bueno-Orovio A, Mincholé A, Zemzemi N, Rodriguez B. Human ventricular activation sequence and the simulation of the electrocardiographic QRS complex and its variability in healthy and intraventricular block conditions. Europace 2017; 18:iv4-iv15. [PMID: 28011826 PMCID: PMC5225966 DOI: 10.1093/europace/euw346] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 08/09/2016] [Indexed: 12/01/2022] Open
Abstract
Aims To investigate how variability in activation sequence and passive conduction properties translates into clinical variability in QRS biomarkers, and gain novel physiological knowledge on the information contained in the human QRS complex. Methods and results Multiscale bidomain simulations using a detailed heart-torso human anatomical model are performed to investigate the impact of activation sequence characteristics on clinical QRS biomarkers. Activation sequences are built and validated against experimentally-derived ex vivo and in vivo human activation data. R-peak amplitude exhibits the largest variability in terms of QRS morphology, due to its simultaneous modulation by activation sequence speed, myocardial intracellular and extracellular conductivities, and propagation through the human torso. QRS width, however, is regulated by endocardial activation speed and intracellular myocardial conductivities, whereas QR intervals are only affected by the endocardial activation profile. Variability in the apico-basal location of activation sites on the anterior and posterior left ventricular wall is associated with S-wave progression in limb and precordial leads, respectively, and occasional notched QRS complexes in precordial derivations. Variability in the number of early activation sites successfully reproduces pathological abnormalities of the human conduction system in the QRS complex. Conclusion Variability in activation sequence and passive conduction properties captures and explains a large part of the clinical variability observed in the human QRS complex. Our physiological insights allow for a deeper interpretation of human QRS biomarkers in terms of QRS morphology and location of early endocardial activation sites. This might be used to attain a better patient-specific knowledge of activation sequence from routine body-surface electrocardiograms.
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Affiliation(s)
- Louie Cardone-Noott
- Department of Computer Science and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford OX1 3QD, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford OX1 3QD, UK
| | - Ana Mincholé
- Department of Computer Science and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford OX1 3QD, UK
| | - Nejib Zemzemi
- INRIA Bordeaux Sud-Ouest, 200 avenue de la vieille tour, Talence Cedex 33405, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, foundation Bordeaux Université, F-33600 Pessac Bordeaux, France
| | - Blanca Rodriguez
- Department of Computer Science and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford OX1 3QD, UK
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