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Bodagh N, Klis M, Gharaviri A, Vigneswaran V, Vickneson K, Williams MC, Niederer S, O'Neill M, Williams SE. Time to capitalise on artificial intelligence in cardiac electrophysiology. J Interv Card Electrophysiol 2024:10.1007/s10840-024-01803-0. [PMID: 38602602 DOI: 10.1007/s10840-024-01803-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Accepted: 03/28/2024] [Indexed: 04/12/2024]
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Khenkina N, Aimo A, Fabiani I, Masci PG, Sagris D, Williams SE, Mavraganis G, Chen HS, Wintermark M, Michel P, Ntaios G, Georgiopoulos G. Magnetic resonance imaging for diagnostic workup of embolic stroke of undetermined source: A systematic review. Int J Stroke 2024; 19:293-304. [PMID: 37435743 DOI: 10.1177/17474930231189946] [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] [Indexed: 07/13/2023]
Abstract
BACKGROUND Embolic stroke of undetermined source (ESUS) refers to ischemic stroke where the underlying cause of thromboembolism cannot be found despite the recommended diagnostic workup. Unidentified source of emboli hinders clinical decision-making and patient management with detrimental consequences on long-term prognosis. The rapid development and versatility of magnetic resonance imaging (MRI) make it an appealing addition to the diagnostic routine of patients with ESUS for the assessment of potential vascular and cardiac embolic sources. AIMS To review the use of MRI in the identification of cardiac and vascular embolic sources in ESUS and to assess the reclassification value of MRI examinations added to the conventional workup of ESUS. SUMMARY OF REVIEW We reviewed the use of cardiac and vascular MRI for the identification of a variety of embolic sources associated with ESUS, including atrial cardiomyopathy, left ventricular pathologies, and supracervical atherosclerosis in carotid and intracranial arteries and in distal thoracic aorta. The additional reclassification after MRI examinations added to the workup of patients with ESUS ranged from 6.1% to 82.3% and varied depending on the combination of imaging modalities. CONCLUSION MRI techniques allow us to identify additional cardiac and vascular embolic sources and may further decrease the prevalence of patients with the diagnosis of ESUS.
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Affiliation(s)
- Natallia Khenkina
- Postgraduate School of Diagnostic and Interventional Radiology, University of Milan, Milan, Italy
| | - Alberto Aimo
- Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy
- Cardiology Division, Fondazione Toscana Gabriele Monasterio, Pisa, Italy
| | - Iacopo Fabiani
- Cardiology Division, Fondazione Toscana Gabriele Monasterio, Pisa, Italy
| | - Pier Giorgio Masci
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Dimitrios Sagris
- Liverpool Centre of Cardiovascular Sciences, University of Liverpool, Liverpool, UK
| | | | - George Mavraganis
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
| | - Hui-Sheng Chen
- Department of Neurology, General Hospital of Northern Theater Command, Shenyang, China
| | - Max Wintermark
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Patrik Michel
- Stroke Center, Neurology Service, Department of Clinical Neurosciences, Lausanne University Hospital, Lausanne, Switzerland
| | - George Ntaios
- Department of Internal Medicine, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece
| | - Georgios Georgiopoulos
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
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Kotadia ID, O'Dowling R, Aboagye A, Crawley RJ, Bodagh N, Gharaviri A, O'Hare D, Solis‐Lemus JA, Roney CH, Sim I, Ramsey D, Newby D, Chiribiri A, Plein S, Sztriha L, Scott P, Masci P, Harrison J, Williams MC, Birns J, Somerville P, Bhalla A, Niederer S, O'Neill M, Williams SE. High Prevalence of New Clinically Significant Findings in Patients With Embolic Stroke of Unknown Source Evaluated by Cardiac Magnetic Resonance Imaging. J Am Heart Assoc 2024; 13:e031489. [PMID: 38240222 PMCID: PMC11056130 DOI: 10.1161/jaha.123.031489] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/05/2023] [Indexed: 02/07/2024]
Abstract
BACKGROUND Embolic stroke of unknown source (ESUS) accounts for 1 in 6 ischemic strokes. Current guidelines do not recommend routine cardiac magnetic resonance (CMR) imaging in ESUS, and beyond the identification of cardioembolic sources, there are no data assessing new clinical findings from CMR in ESUS. This study aimed to assess the prevalence of new cardiac and noncardiac findings and to determine their impact on clinical care in patients with ESUS. METHODS AND RESULTS In this prospective, multicenter, observational study, CMR imaging was performed within 3 months of ESUS. All scans were reported according to standard clinical practice. A new clinical finding was defined as one not previously identified through prior clinical evaluation. A clinically significant finding was defined as one resulting in further investigation, follow-up, or treatment. A change in patient care was defined as initiation of medical, interventional, surgical, or palliative care. From 102 patients recruited, 96 underwent CMR imaging. One or more new clinical findings were observed in 59 patients (61%). New findings were clinically significant in 48 (81%) of these patients. Of 40 patients with a new clinically significant cardiac finding, 21 (53%) experienced a change in care (medical therapy, n=15; interventional/surgical procedure, n=6). In 12 patients with a new clinically significant extracardiac finding, 6 (50%) experienced a change in care (medical therapy, n=4; palliative care, n=2). CONCLUSIONS CMR imaging identifies new clinically significant cardiac and noncardiac findings in half of patients with recent ESUS. Advanced cardiovascular screening should be considered in patients with ESUS. REGISTRATION URL: https://www.clinicaltrials.gov; Unique identifier: NCT04555538.
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Affiliation(s)
- Irum D. Kotadia
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Robert O'Dowling
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Akosua Aboagye
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Richard J. Crawley
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Neil Bodagh
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Ali Gharaviri
- Centre for Cardiovascular Science, The University of EdinburghEdinburghUnited Kingdom
| | - Daniel O'Hare
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Jose Alonso Solis‐Lemus
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Caroline H. Roney
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | | | - David Newby
- Centre for Cardiovascular Science, The University of EdinburghEdinburghUnited Kingdom
| | - Amedeo Chiribiri
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Sven Plein
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | | | - Paul Scott
- King’s College HospitalLondonUnited Kingdom
| | - Pier‐Giorgio Masci
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | | | - Michelle C. Williams
- Centre for Cardiovascular Science, The University of EdinburghEdinburghUnited Kingdom
| | - Jonathan Birns
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Peter Somerville
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Ajay Bhalla
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
- Guy’s and St Thomas’ National Health Service Foundation TrustLondonUnited Kingdom
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College LondonLondonUnited Kingdom
- Centre for Cardiovascular Science, The University of EdinburghEdinburghUnited Kingdom
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Mehari T, Sundar A, Bosnjakovic A, Harris P, Williams SE, Loewe A, Doessel O, Nagel C, Strodthoff N, Aston PJ. ECG Feature Importance Rankings: Cardiologists vs. Algorithms. IEEE J Biomed Health Inform 2024; PP:1-11. [PMID: 38227406 DOI: 10.1109/jbhi.2024.3354301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Feature importance methods promise to provide a ranking of features according to importance for a given classification task. A wide range of methods exist but their rankings often disagree and they are inherently difficult to evaluate due to a lack of ground truth beyond synthetic datasets. In this work, we put feature importance methods to the test on real-world data in the domain of cardiology, where we try to distinguish three specific pathologies from healthy subjects based on ECG features comparing to features used in cardiologists' decision rules as ground truth. We found that the SHAP and LIME methods and Chi-squared test all worked well together with the native Random forest and Logistic regression feature rankings. Some methods gave inconsistent results, which included the Maximum Relevance Minimum Redundancy and Neighbourhood Component Analysis methods. The permutation-based methods generally performed quite poorly. A surprising result was found in the case of left bundle branch block, where T-wave morphology features were consistently identified as being important for diagnosis, but are not used by clinicians.
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5
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Kotadia ID, Dias M, Roney C, Parker RA, O’Dowling R, Bodagh N, Lemus-Solis JA, O’Hare D, Sim I, Newby D, Niederer S, Birns J, Sommerville P, Bhalla A, O’Neill M, Williams SE. AF and in-hospital mortality in COVID-19 patients. Heart Rhythm O2 2023; 4:700-707. [PMID: 38034887 PMCID: PMC10685157 DOI: 10.1016/j.hroo.2023.10.004] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023] Open
Abstract
Background There are conflicting data on whether new-onset atrial fibrillation (AF) is independently associated with poor outcomes in COVID-19 patients. This study represents the largest dataset curated by manual chart review comparing clinical outcomes between patients with sinus rhythm, pre-existing AF, and new-onset AF. Objective The primary aim of this study was to assess patient outcomes in COVID-19 patients with sinus rhythm, pre-existing AF, and new-onset AF. The secondary aim was to evaluate predictors of new-onset AF in patients with COVID-19 infection. Methods This was a single-center retrospective study of patients with a confirmed diagnosis of COVID-19 admitted between March and September 2020. Patient demographic data, medical history, and clinical outcome data were manually collected. Adjusted comparisons were performed following propensity score matching between those with pre-existing or new-onset AF and those without AF. Results The study population comprised of 1241 patients. A total of 94 (7.6%) patients had pre-existing AF and 42 (3.4%) patients developed new-onset AF. New-onset AF was associated with increased in-hospital mortality before (odds ratio [OR] 3.58, 95% confidence interval [CI] 1.78-7.06, P < .005) and after (OR 2.80, 95% CI 1.01-7.77, P < .005) propensity score matching compared with the no-AF group. However, pre-existing AF was not independently associated with in-hospital mortality compared with patients with no AF (postmatching OR: 1.13, 95% CI 0.57-2.21, P = .732). Conclusion New-onset AF, but not pre-existing AF, was independently associated with elevated mortality in patients hospitalised with COVID-19. This observation highlights the need for careful monitoring of COVID-19 patients with new-onset AF. Further research is needed to explain the mechanistic relationship between new-onset AF and clinical outcomes in COVID-19 patients.
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Affiliation(s)
- Irum D. Kotadia
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Maria Dias
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Caroline Roney
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Richard A. Parker
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Robert O’Dowling
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Neil Bodagh
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | | | - Daniel O’Hare
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Iain Sim
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - David Newby
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Steven Niederer
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Jonathan Birns
- Stroke Medicine, Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Peter Sommerville
- Stroke Medicine, Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Ajay Bhalla
- Stroke Medicine, Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Mark O’Neill
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Steven E. Williams
- Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
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6
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Gillette K, Gsell MAF, Nagel C, Bender J, Winkler B, Williams SE, Bär M, Schäffter T, Dössel O, Plank G, Loewe A. MedalCare-XL: 16,900 healthy and pathological synthetic 12 lead ECGs from electrophysiological simulations. Sci Data 2023; 10:531. [PMID: 37553349 PMCID: PMC10409805 DOI: 10.1038/s41597-023-02416-4] [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: 03/29/2023] [Accepted: 07/25/2023] [Indexed: 08/10/2023] Open
Abstract
Mechanistic cardiac electrophysiology models allow for personalized simulations of the electrical activity in the heart and the ensuing electrocardiogram (ECG) on the body surface. As such, synthetic signals possess known ground truth labels of the underlying disease and can be employed for validation of machine learning ECG analysis tools in addition to clinical signals. Recently, synthetic ECGs were used to enrich sparse clinical data or even replace them completely during training leading to improved performance on real-world clinical test data. We thus generated a novel synthetic database comprising a total of 16,900 12 lead ECGs based on electrophysiological simulations equally distributed into healthy control and 7 pathology classes. The pathological case of myocardial infraction had 6 sub-classes. A comparison of extracted features between the virtual cohort and a publicly available clinical ECG database demonstrated that the synthetic signals represent clinical ECGs for healthy and pathological subpopulations with high fidelity. The ECG database is split into training, validation, and test folds for development and objective assessment of novel machine learning algorithms.
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Affiliation(s)
- Karli Gillette
- Gottfried Schatz Research Center: Division of Medical Physics and Biophysics, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Matthias A F Gsell
- Gottfried Schatz Research Center: Division of Medical Physics and Biophysics, Medical University of Graz, Graz, Austria
| | - Claudia Nagel
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Jule Bender
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Benjamin Winkler
- Physikalisch-Technische Bundesanstalt, National Metrology Institute, Berlin, Germany
| | - Steven E Williams
- King's College London, London, United Kingdom
- University of Edinburgh, Edinburgh, United Kingdom
| | - Markus Bär
- Physikalisch-Technische Bundesanstalt, National Metrology Institute, Berlin, Germany
| | - Tobias Schäffter
- Physikalisch-Technische Bundesanstalt, National Metrology Institute, Berlin, Germany
- King's College London, London, United Kingdom
- Biomedical Engineering, Technische Universität Berlin, Einstein Centre Digital Future, Berlin, Germany
| | - Olaf Dössel
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Gernot Plank
- Gottfried Schatz Research Center: Division of Medical Physics and Biophysics, Medical University of Graz, Graz, Austria.
- BioTechMed-Graz, Graz, Austria.
| | - Axel Loewe
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
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7
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Solís-Lemus JA, Baptiste T, Barrows R, Sillett C, Gharaviri A, Raffaele G, Razeghi O, Strocchi M, Sim I, Kotadia I, Bodagh N, O'Hare D, O'Neill M, Williams SE, Roney C, Niederer S. Evaluation of an open-source pipeline to create patient-specific left atrial models: A reproducibility study. Comput Biol Med 2023; 162:107009. [PMID: 37301099 PMCID: PMC10790305 DOI: 10.1016/j.compbiomed.2023.107009] [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: 01/16/2023] [Revised: 04/11/2023] [Accepted: 05/03/2023] [Indexed: 06/12/2023]
Abstract
This work presents an open-source software pipeline to create patient-specific left atrial models with fibre orientations and a fibrDEFAULTosis map, suitable for electrophysiology simulations, and quantifies the intra and inter observer reproducibility of the model creation. The semi-automatic pipeline takes as input a contrast enhanced magnetic resonance angiogram, and a late gadolinium enhanced (LGE) contrast magnetic resonance (CMR). Five operators were allocated 20 cases each from a set of 50 CMR datasets to create a total of 100 models to evaluate inter and intra-operator variability. Each output model consisted of: (1) a labelled surface mesh open at the pulmonary veins and mitral valve, (2) fibre orientations mapped from a diffusion tensor MRI (DTMRI) human atlas, (3) fibrosis map extracted from the LGE-CMR scan, and (4) simulation of local activation time (LAT) and phase singularity (PS) mapping. Reproducibility in our pipeline was evaluated by comparing agreement in shape of the output meshes, fibrosis distribution in the left atrial body, and fibre orientations. Reproducibility in simulations outputs was evaluated in the LAT maps by comparing the total activation times, and the mean conduction velocity (CV). PS maps were compared with the structural similarity index measure (SSIM). The users processed in total 60 cases for inter and 40 cases for intra-operator variability. Our workflow allows a single model to be created in 16.72 ± 12.25 min. Similarity was measured with shape, percentage of fibres oriented in the same direction, and intra-class correlation coefficient (ICC) for the fibrosis calculation. Shape differed noticeably only with users' selection of the mitral valve and the length of the pulmonary veins from the ostia to the distal end; fibrosis agreement was high, with ICC of 0.909 (inter) and 0.999 (intra); fibre orientation agreement was high with 60.63% (inter) and 71.77% (intra). The LAT showed good agreement, where the median ± IQR of the absolute difference of the total activation times was 2.02 ± 2.45 ms for inter, and 1.37 ± 2.45 ms for intra. Also, the average ± sd of the mean CV difference was -0.00404 ± 0.0155 m/s for inter, and 0.0021 ± 0.0115 m/s for intra. Finally, the PS maps showed a moderately good agreement in SSIM for inter and intra, where the mean ± sd SSIM for inter and intra were 0.648 ± 0.21 and 0.608 ± 0.15, respectively. Although we found notable differences in the models, as a consequence of user input, our tests show that the uncertainty caused by both inter and intra-operator variability is comparable with uncertainty due to estimated fibres, and image resolution accuracy of segmentation tools.
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Affiliation(s)
- José Alonso Solís-Lemus
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK.
| | - Tiffany Baptiste
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Rosie Barrows
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Charles Sillett
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Ali Gharaviri
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; Centre for Cardiovascular Science, University of Edinburgh, Old College, South Bridge, Edinburgh, EH8 9YL, Scotland, UK
| | - Giulia Raffaele
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; School of Medical Education, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Orod Razeghi
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; Department of Haematology, NHS Blood and Transplant Centre, University of Cambridge, Cambridge, UK
| | - Marina Strocchi
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Iain Sim
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Irum Kotadia
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Neil Bodagh
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Daniel O'Hare
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Mark O'Neill
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK
| | - Steven E Williams
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; Centre for Cardiovascular Science, University of Edinburgh, Old College, South Bridge, Edinburgh, EH8 9YL, Scotland, UK
| | - Caroline Roney
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; Queen Mary University of London, Mile End Rd, Bethnal Green, London, E1 4NS, UK
| | - Steven Niederer
- School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas Hospital, London, SE1 7EH, UK; Alan Turing Institute, British Library, 96 Euston Rd, London, NW1 2DB, UK
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8
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Bodagh N, Williams MC, Vickneson K, Gharaviri A, Niederer S, Williams SE. State of the art paper: Cardiac computed tomography of the left atrium in atrial fibrillation. J Cardiovasc Comput Tomogr 2023; 17:166-176. [PMID: 36966040 PMCID: PMC10689253 DOI: 10.1016/j.jcct.2023.03.002] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 02/06/2023] [Accepted: 03/11/2023] [Indexed: 03/27/2023]
Abstract
The clinical spectrum of atrial fibrillation means that a patient-individualized approach is required to ensure optimal treatment. Cardiac computed tomography can accurately delineate atrial structure and function and could contribute to a personalized care pathway for atrial fibrillation patients. The imaging modality offers excellent spatial resolution and has been utilised in pre-, peri- and post-procedural care for patients with atrial fibrillation. Advances in temporal resolution, acquisition times and analysis techniques suggest potential expanding roles for cardiac computed tomography in the future management of patients with atrial fibrillation. The aim of the current review is to discuss the use of cardiac computed tomography in atrial fibrillation in pre-, peri- and post-procedural settings. Potential future applications of cardiac computed tomography including atrial wall thickness assessment and epicardial fat volume quantification are discussed together with emerging analysis techniques including computational modelling and machine learning with attention paid to how these developments may contribute to a personalized approach to atrial fibrillation management.
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Affiliation(s)
- Neil Bodagh
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK.
| | | | - Keeran Vickneson
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Ali Gharaviri
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK; Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
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9
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Bodagh N, Kotadia I, Gharaviri A, Zelaya F, Birns J, Bhalla A, Sommerville P, Niederer S, O’Neill M, Williams SE. The Impact of Atrial Fibrillation Treatment Strategies on Cognitive Function. J Clin Med 2023; 12:3050. [PMID: 37176490 PMCID: PMC10179566 DOI: 10.3390/jcm12093050] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/12/2023] [Accepted: 04/17/2023] [Indexed: 05/15/2023] Open
Abstract
There is increasing evidence to suggest that atrial fibrillation is associated with a heightened risk of dementia. The mechanism of interaction is unclear. Atrial fibrillation-induced cerebral infarcts, hypoperfusion, systemic inflammation, and anticoagulant therapy-induced cerebral microbleeds, have been proposed to explain the link between these conditions. An understanding of the pathogenesis of atrial fibrillation-associated cognitive decline may enable the development of treatment strategies targeted towards the prevention of dementia in atrial fibrillation patients. The aim of this review is to explore the impact that existing atrial fibrillation treatment strategies may have on cognition and the putative mechanisms linking the two conditions. This review examines how components of the 'Atrial Fibrillation Better Care pathway' (stroke risk reduction, rhythm control, rate control, and risk factor management) may influence the trajectory of atrial fibrillation-associated cognitive decline. The requirements for further prospective studies to understand the mechanistic link between atrial fibrillation and dementia and to develop treatment strategies targeted towards the prevention of atrial fibrillation-associated cognitive decline, are highlighted.
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Affiliation(s)
- Neil Bodagh
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Irum Kotadia
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Ali Gharaviri
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Fernando Zelaya
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Jonathan Birns
- St Thomas’ Hospital, Guys and St Thomas’ NHS Foundation Trust, London SE1 7EH, UK
| | - Ajay Bhalla
- St Thomas’ Hospital, Guys and St Thomas’ NHS Foundation Trust, London SE1 7EH, UK
| | - Peter Sommerville
- St Thomas’ Hospital, Guys and St Thomas’ NHS Foundation Trust, London SE1 7EH, UK
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
| | - Mark O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
- St Thomas’ Hospital, Guys and St Thomas’ NHS Foundation Trust, London SE1 7EH, UK
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, UK
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh EH16 4TJ, UK
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Williams MC, Williams SE, Newby DE. Artificial Intelligence-based Text-to-Image Generation of Cardiac CT. Radiol Cardiothorac Imaging 2023; 5:e220297. [PMID: 37274418 PMCID: PMC10233407 DOI: 10.1148/ryct.220297] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/17/2023] [Accepted: 02/28/2023] [Indexed: 06/06/2023]
Affiliation(s)
- Michelle C. Williams
- From the British Heart Foundation Centre for Cardiovascular Science,
University of Edinburgh, Chancellor’s Building, 49 Little France
Crescent, Edinburgh EH16 SUF, Scotland
| | - Steven E. Williams
- From the British Heart Foundation Centre for Cardiovascular Science,
University of Edinburgh, Chancellor’s Building, 49 Little France
Crescent, Edinburgh EH16 SUF, Scotland
| | - David E. Newby
- From the British Heart Foundation Centre for Cardiovascular Science,
University of Edinburgh, Chancellor’s Building, 49 Little France
Crescent, Edinburgh EH16 SUF, Scotland
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11
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Xu H, Williams SE, Williams MC, Newby DE, Taylor J, Neji R, Kunze KP, Niederer SA, Young AA. Deep learning estimation of three-dimensional left atrial shape from two-chamber and four-chamber cardiac long axis views. Eur Heart J Cardiovasc Imaging 2023; 24:607-615. [PMID: 36725705 PMCID: PMC10125223 DOI: 10.1093/ehjci/jead010] [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: 10/26/2022] [Revised: 12/16/2022] [Accepted: 01/09/2023] [Indexed: 02/03/2023] Open
Abstract
AIMS Left atrial volume is commonly estimated using the bi-plane area-length method from two-chamber (2CH) and four-chamber (4CH) long axes views. However, this can be inaccurate due to a violation of geometric assumptions. We aimed to develop a deep learning neural network to infer 3D left atrial shape, volume and surface area from 2CH and 4CH views. METHODS AND RESULTS A 3D UNet was trained and tested using 2CH and 4CH segmentations generated from 3D coronary computed tomography angiography (CCTA) segmentations (n = 1700, with 1400/100/200 cases for training/validating/testing). An independent test dataset from another institution was also evaluated, using cardiac magnetic resonance (CMR) 2CH and 4CH segmentations as input and 3D CCTA segmentations as the ground truth (n = 20). For the 200 test cases generated from CCTA, the network achieved a mean Dice score value of 93.7%, showing excellent 3D shape reconstruction from two views compared with the 3D segmentation Dice of 97.4%. The network also showed significantly lower mean absolute error values of 3.5 mL/4.9 cm2 for LA volume/surface area respectively compared to the area-length method errors of 13.0 mL/34.1 cm2 respectively (P < 0.05 for both). For the independent CMR test set, the network achieved accurate 3D shape estimation (mean Dice score value of 87.4%), and a mean absolute error values of 6.0 mL/5.7 cm2 for left atrial volume/surface area respectively, significantly less than the area-length method errors of 14.2 mL/19.3 cm2 respectively (P < 0.05 for both). CONCLUSIONS Compared to the bi-plane area-length method, the network showed higher accuracy and robustness for both volume and surface area.
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Affiliation(s)
- Hao Xu
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK
| | - Steven E Williams
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK.,University/BHF Centre for Cardiovascular Science, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Michelle C Williams
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - David E Newby
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Jonathan Taylor
- 3DLab, Sheffield Teaching Hospitals NHS Foundation Trust, Northern General Hospital, Sheffield, s5 7AU, UK
| | - Radhouene Neji
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK.,MR Research Collaborations, Siemens Healthcare Limited, Newton House, Sir William Siemens Square, Frimley, Camberley, Surrey, GU16 8QD, UK
| | - Karl P Kunze
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK.,MR Research Collaborations, Siemens Healthcare Limited, Newton House, Sir William Siemens Square, Frimley, Camberley, Surrey, GU16 8QD, UK
| | - Steven A Niederer
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK
| | - Alistair A Young
- Department of Biomedical Engineering, King's College London, Lambeth Palace Rd, London SE1 7EU, UK
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12
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Corrado C, Roney CH, Razeghi O, Lemus JAS, Coveney S, Sim I, Williams SE, O'Neill MD, Wilkinson RD, Clayton RH, Niederer SA. Quantifying the impact of shape uncertainty on predicted arrhythmias. Comput Biol Med 2023; 153:106528. [PMID: 36634600 DOI: 10.1016/j.compbiomed.2022.106528] [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: 09/09/2022] [Revised: 12/15/2022] [Accepted: 12/31/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND Personalised computer models are increasingly used to diagnose cardiac arrhythmias and tailor treatment. Patient-specific models of the left atrium are often derived from pre-procedural imaging of anatomy and fibrosis. These images contain noise that can affect simulation predictions. There are few computationally tractable methods for propagating uncertainties from images to clinical predictions. METHOD We describe the left atrium anatomy using our Bayesian shape model that captures anatomical uncertainty in medical images and has been validated on 63 independent clinical images. This algorithm describes the left atrium anatomy using Nmodes=15 principal components, capturing 95% of the shape variance and calculated from 70 clinical cardiac magnetic resonance (CMR) images. Latent variables encode shape uncertainty: we evaluate their posterior distribution for each new anatomy. We assume a normally distributed prior. We use the unscented transform to sample from the posterior shape distribution. For each sample, we assign the local material properties of the tissue using the projection of late gadolinium enhancement CMR (LGE-CMR) onto the anatomy to estimate local fibrosis. To test which activation patterns an atrium can sustain, we perform an arrhythmia simulation for each sample. We consider 34 possible outcomes (31 macro-re-entries, functional re-entry, atrial fibrillation, and non-sustained arrhythmia). For each sample, we determine the outcome by comparing pre- and post-ablation activation patterns following a cross-field stimulus. RESULTS We create patient-specific atrial electrophysiology models of ten patients. We validate the mean and standard deviation maps from the unscented transform with the same statistics obtained with 12,000 Monte Carlo (ground truth) samples. We found discrepancies <3% and <2% for the mean and standard deviation for fibrosis burden and activation time, respectively. For each patient case, we then compare the predicted outcome from a model built on the clinical data (deterministic approach) with the probability distribution obtained from the simulated samples. We found that the deterministic approach did not predict the most likely outcome in 80% of the cases. Finally, we estimate the influence of each source of uncertainty independently. Fixing the anatomy to the posterior mean and maintaining uncertainty in fibrosis reduced the prediction of self-terminating arrhythmias from ≃14% to ≃7%. Keeping the fibrosis fixed to the sample mean while retaining uncertainty in shape decreased the prediction of substrate-driven arrhythmias from ≃33% to ≃18% and increased the prediction of macro-re-entries from ≃54% to ≃68%. CONCLUSIONS We presented a novel method for propagating shape uncertainty in atrial models through to uncertainty in numerical simulations. The algorithm takes advantage of the unscented transform to compute the output distribution of the outcomes. We validated the unscented transform as a viable sampling strategy to deal with anatomy uncertainty. We then showed that the prediction computed with a deterministic model does not always coincide with the most likely outcome. Finally, we found that shape uncertainty affects the predictions of macro-re-entries, while fibrosis uncertainty affects the predictions of functional re-entries.
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Affiliation(s)
- Cesare Corrado
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom.
| | - Caroline H Roney
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom; School of Engineering and Materials Science, Queen Mary University of London, London, United Kingdom
| | - Orod Razeghi
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom; UCL Centre for Advanced Research Computing, London, United Kingdom
| | - Josè Alonso Solís Lemus
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom
| | - Sam Coveney
- Insigneo Institute for in-silico Medicine and Department of Computer Science, University of Sheffield, Sheffield, United Kingdom
| | - Iain Sim
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom
| | - Steven E Williams
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom
| | - Mark D O'Neill
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom
| | - Richard D Wilkinson
- School of Mathematical Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Richard H Clayton
- Insigneo Institute for in-silico Medicine and Department of Computer Science, University of Sheffield, Sheffield, United Kingdom
| | - Steven A Niederer
- Division of Imaging Sciences & Biomedical Engineering, King's College London, London SE17EH, United Kingdom
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13
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Qureshi A, Lip GYH, Nordsletten DA, Williams SE, Aslanidi O, de Vecchi A. Imaging and biophysical modelling of thrombogenic mechanisms in atrial fibrillation and stroke. Front Cardiovasc Med 2023; 9:1074562. [PMID: 36733827 PMCID: PMC9887999 DOI: 10.3389/fcvm.2022.1074562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/29/2022] [Indexed: 01/18/2023] Open
Abstract
Atrial fibrillation (AF) underlies almost one third of all ischaemic strokes, with the left atrial appendage (LAA) identified as the primary thromboembolic source. Current stroke risk stratification approaches, such as the CHA2DS2-VASc score, rely mostly on clinical comorbidities, rather than thrombogenic mechanisms such as blood stasis, hypercoagulability and endothelial dysfunction-known as Virchow's triad. While detection of AF-related thrombi is possible using established cardiac imaging techniques, such as transoesophageal echocardiography, there is a growing need to reliably assess AF-patient thrombogenicity prior to thrombus formation. Over the past decade, cardiac imaging and image-based biophysical modelling have emerged as powerful tools for reproducing the mechanisms of thrombogenesis. Clinical imaging modalities such as cardiac computed tomography, magnetic resonance and echocardiographic techniques can measure blood flow velocities and identify LA fibrosis (an indicator of endothelial dysfunction), but imaging remains limited in its ability to assess blood coagulation dynamics. In-silico cardiac modelling tools-such as computational fluid dynamics for blood flow, reaction-diffusion-convection equations to mimic the coagulation cascade, and surrogate flow metrics associated with endothelial damage-have grown in prevalence and advanced mechanistic understanding of thrombogenesis. However, neither technique alone can fully elucidate thrombogenicity in AF. In future, combining cardiac imaging with in-silico modelling and integrating machine learning approaches for rapid results directly from imaging data will require development under a rigorous framework of verification and clinical validation, but may pave the way towards enhanced personalised stroke risk stratification in the growing population of AF patients. This Review will focus on the significant progress in these fields.
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Affiliation(s)
- Ahmed Qureshi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,*Correspondence: Ahmed Qureshi,
| | - Gregory Y. H. Lip
- Liverpool Centre for Cardiovascular Science, University of Liverpool and Liverpool Heart & Chest Hospital, Liverpool, United Kingdom
| | - David A. Nordsletten
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
| | - Oleg Aslanidi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Adelaide de Vecchi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
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14
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Whitaker J, Bredfeldt J, Williams SE, Qian P, Chang D, Mak RH, Cochet H, Sauer W, Zei PC, Tedrow U. Ventricular Conduction Velocity Following Multimodal Ablation Including Stereotactic Body Radiation Therapy for Refractory Ventricular Tachycardia. JACC Clin Electrophysiol 2023; 9:119-121. [PMID: 36697191 DOI: 10.1016/j.jacep.2022.08.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 08/16/2022] [Indexed: 11/05/2022]
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15
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Bodagh N, Yap R, Kotadia I, Sim I, Bhalla A, Somerville P, O'Neill M, Williams SE. Impact of catheter ablation versus medical therapy on cognitive function in atrial fibrillation: a systematic review. J Interv Card Electrophysiol 2022; 65:271-286. [PMID: 35380337 PMCID: PMC9550702 DOI: 10.1007/s10840-022-01196-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [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: 12/16/2021] [Accepted: 03/21/2022] [Indexed: 12/22/2022]
Abstract
PURPOSE Atrial fibrillation is associated with an increased risk of cognitive impairment. It is unclear whether the restoration of sinus rhythm with catheter ablation may modify this risk. We conducted a systematic review of studies comparing cognitive outcomes following catheter ablation with medical therapy (rate and/or rhythm control) in atrial fibrillation. METHODS Searches were performed on the following databases from their inception to 17 October 2021: PubMed, OVID Medline, Embase and Cochrane Library. The inclusion criteria comprised studies comparing catheter ablation against medical therapy (rate and/or rhythm control in conjunction with anticoagulation where appropriate) which included cognitive assessment and/or a diagnosis of dementia as an outcome. RESULTS A total of 599 records were screened. Ten studies including 15,886 patients treated with catheter ablation and 42,684 patients treated with medical therapy were included. Studies which compared the impact of catheter ablation versus medical therapy on quantitative assessments of cognitive function yielded conflicting results. In studies, examining new onset dementia during follow-up, catheter ablation was associated with a lower risk of subsequent dementia diagnosis compared to medical therapy (hazard ratio: 0.60 (95% confidence interval 0.42-0.88, p < 0.05)). CONCLUSION The accumulating evidence linking atrial fibrillation with cognitive impairment warrants the design of atrial fibrillation treatment strategies aimed at minimising cognitive decline. However, the impact of catheter ablation and atrial fibrillation medical therapy on cognitive decline is currently uncertain. Future studies investigating atrial fibrillation treatment strategies should include cognitive outcomes as important clinical endpoints.
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Affiliation(s)
- Neil Bodagh
- King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK.
| | - Reuben Yap
- Princess Royal University Hospital, Orpington, UK
| | - Irum Kotadia
- King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK
- Guys and St. Thomas' NHS Foundation Trust, London, UK
| | - Iain Sim
- King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Ajay Bhalla
- Guys and St. Thomas' NHS Foundation Trust, London, UK
| | | | - Mark O'Neill
- King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK
- Guys and St. Thomas' NHS Foundation Trust, London, UK
| | - Steven E Williams
- King's College London, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
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16
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Mooiweer R, Schneider R, Krafft AJ, Empanger K, Stroup J, Neofytou AP, Mukherjee RK, Williams SE, Lloyd T, O'Neill M, Razavi R, Schaeffter T, Neji R, Roujol S. Active Tracking-based cardiac triggering for MR-thermometry during radiofrequency ablation therapy in the left ventricle. Front Cardiovasc Med 2022; 9:971869. [PMID: 36093156 PMCID: PMC9453599 DOI: 10.3389/fcvm.2022.971869] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 07/29/2022] [Indexed: 11/13/2022] Open
Abstract
Cardiac MR thermometry shows promise for real-time guidance of radiofrequency ablation of cardiac arrhythmias. This technique uses ECG triggering, which can be unreliable in this situation. A prospective cardiac triggering method was developed for MR thermometry using the active tracking (AT) signal measured from catheter microcoils. In the proposed AT-based cardiac triggering (AT-trig) sequence, AT modules were repeatedly acquired to measure the catheter motion until a cardiac trigger was identified to start cardiac MR thermometry using single-shot echo-planar imaging. The AT signal was bandpass filtered to extract the motion induced by the beating heart, and cardiac triggers were defined as the extremum (peak or valley) of the filtered AT signal. AT-trig was evaluated in a beating heart phantom and in vivo in the left ventricle of a swine during temperature stability experiments (6 locations) and during one ablation. Stability was defined as the standard deviation over time. In the phantom, AT-trig enabled triggering of MR thermometry and resulted in higher temperature stability than an untriggered sequence. In all in vivo experiments, AT-trig intervals matched ECG-derived RR intervals. Mis-triggers were observed in 1/12 AT-trig stability experiments. Comparable stability of MR thermometry was achieved using peak AT-trig (1.0 ± 0.4°C), valley AT-trig (1.1 ± 0.5°C), and ECG triggering (0.9 ± 0.4°C). These experiments show that continuously acquired AT signal for prospective cardiac triggering is feasible. MR thermometry with AT-trig leads to comparable temperature stability as with conventional ECG triggering. AT-trig could serve as an alternative cardiac triggering strategy in situations where ECG triggering is not effective.
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Affiliation(s)
- Ronald Mooiweer
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
- MR Research Collaborations, Siemens Healthcare Limited, Camberley, United Kingdom
| | | | | | - Katy Empanger
- Imricor Medical Systems, Burnsville, MN, United States
| | - Jason Stroup
- Imricor Medical Systems, Burnsville, MN, United States
| | - Alexander Paul Neofytou
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Rahul K. Mukherjee
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
| | - Tom Lloyd
- Imricor Medical Systems, Burnsville, MN, United States
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Tobias Schaeffter
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
- MR Research Collaborations, Siemens Healthcare Limited, Camberley, United Kingdom
| | - Sébastien Roujol
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
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17
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O’Neill L, Sim I, O’Hare D, Whitaker J, Mukherjee RK, Razeghi O, Niederer S, Wright M, Chiribiri A, Frigiola A, O’Neill MD, Williams SE. CArdiac MagnEtic resonance assessment of bi-Atrial fibrosis in secundum atrial septal defects patients: CAMERA-ASD study. Eur Heart J Cardiovasc Imaging 2022; 23:1231-1239. [PMID: 34568942 PMCID: PMC9365304 DOI: 10.1093/ehjci/jeab188] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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: 09/29/2020] [Indexed: 12/25/2022] Open
Abstract
AIMS Atrial septal defects (ASD) are associated with atrial arrhythmias, but the arrhythmia substrate in these patients is poorly defined. We hypothesized that bi-atrial fibrosis is present and that right atrial fibrosis is associated with atrial arrhythmias in ASD patients. We aimed to evaluate the extent of bi-atrial fibrosis in ASD patients and to investigate the relationships between bi-atrial fibrosis, atrial arrhythmias, shunt fraction, and age. METHODS AND RESULTS Patients with uncorrected secundum ASDs (n = 36; 50.4 ± 13.6 years) underwent cardiac magnetic resonance imaging with atrial late gadolinium enhancement. Comparison was made to non-congenital heart disease patients (n = 36; 60.3 ± 10.5 years) with paroxysmal atrial fibrillation (AF). Cardiac magnetic resonance parameters associated with atrial arrhythmias were identified and the relationship between bi-atrial structure, age, and shunt fraction studied. Bi-atrial fibrosis burden was greater in ASD patients than paroxysmal AF patients (20.7 ± 14% vs. 10.1 ± 8.6% and 14.8 ± 8.5% vs. 8.6 ± 6.1% for right and left atria respectively, P = 0.001 for both). In ASD patients, right atrial fibrosis burden was greater in those with than without atrial arrhythmias (33.4 ± 18.7% vs. 16.8 ± 10.3%, P = 0.034). On receiver operating characteristic analysis, a right atrial fibrosis burden of 32% had a 92% specificity and 71% sensitivity for predicting the presence of atrial arrhythmias. Neither age nor shunt fraction was associated with bi-atrial fibrosis burden. CONCLUSION Bi-atrial fibrosis burden is greater in ASD patients than non-congenital heart disease patients with paroxysmal AF. Right atrial fibrosis is associated with the presence of atrial arrhythmias in ASD patients. These findings highlight the importance of right atrial fibrosis to atrial arrhythmogenesis in ASD patients.
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Affiliation(s)
- Louisa O’Neill
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Iain Sim
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Daniel O’Hare
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Rahul K Mukherjee
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Orod Razeghi
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Steven Niederer
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Matthew Wright
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Amedeo Chiribiri
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | | | - Mark D O’Neill
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
| | - Steven E Williams
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor North, Wing, St. Thomas’, Hospital, London SE1 7EH, UK
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18
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O'Neill L, Sim I, O'Hare D, Whitaker J, Mukherjee RK, Niederer S, Wright M, Ezzat V, Rosenthal E, Jones MI, Frigiola A, O'Neill MD, Williams SE. Provocation and localization of atrial ectopy in patients with atrial septal defects. J Interv Card Electrophysiol 2022; 65:227-237. [PMID: 35737208 PMCID: PMC9550781 DOI: 10.1007/s10840-022-01273-2] [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] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/07/2022] [Indexed: 11/13/2022]
Abstract
Background Atrial fibrillation (AF) is associated with atrial septal defects (ASDs), but the mechanism of arrhythmia in these patients is poorly understood. We hypothesised that right-sided atrial ectopy may predominate in this cohort. Here, we aimed to localise the origin of spontaneous and provoked atrial ectopy in ASD patients. Methods Following invasive calibration of P-wave axes, 24-h Holter monitoring was used to determine the chamber of origin of spontaneous atrial ectopy. Simultaneous electrogram recording from multiple intra-cardiac catheters was used to determine the chamber of origin of isoprenaline-provoked ectopy. Comparison was made to a group of non-congenital heart disease AF patients. Results Amongst ASD patients, a right-sided origin for spontaneous atrial ectopy was significantly more prevalent than a left-sided origin (24/30 patients with right-sided ectopy vs. 14/30 with left-sided ectopy, P = 0.015). Amongst AF patients, there was no difference in the prevalence of spontaneous right vs. left-sided ectopy. For isoprenaline-provoked ectopy, there was no significant difference in the proportions of patients with right-sided or left-sided ectopy in either group. Conclusions When spontaneous atrial ectopy occurs in ASD patients, it is significantly more prevalent from a right-sided than left-sided origin. Isoprenaline infusion did not reveal the predilection for right-sided ectopy during electrophysiology study.
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Affiliation(s)
- Louisa O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK.
| | - Iain Sim
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Daniel O'Hare
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Rahul K Mukherjee
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Steven Niederer
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Matthew Wright
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | | | | | | | | | - Mark D O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Steven E Williams
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4thFloor North Wing, St. Thomas' Hospital, London, SE1 7EH, UK.,The University of Edinburgh, Edinburgh, UK
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Sim I, Razeghi O, Solis Lemus JA, Mukherjee R, O’hare D, O’neill L, Kotadia I, Roney CH, Wright M, Chiribiri A, Niederer S, O’neill M, Williams SE. Atrial tissue characterisation using electroanatomic voltage mapping and cardiac magnetic resonance imaging. Europace 2022. [DOI: 10.1093/europace/euac053.177] [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: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): British Heart Foundation
Background
Atrial voltage mapping and atrial cardiac magnetic resonance imaging are two contemporary methods for quantification of atrial fibrosis. However, the absence of a gold standard for measuring atrial fibrosis has precluded their direct comparison. Nevertheless, understanding the relative performance of voltage mapping and atrial late gadolinium enhancement for identification of atrial cardiomyopathy remains critical to correctly targeting clinical application of these techniques.
Purpose
To assess the relative performance of electroanatomic voltage mapping and atrial late gadolinium enhancement imaging using three surrogate markers chosen to distinguish pre-procedural utility (progression to recurrent atrial fibrillation following ablation) from potential utility for providing atrial fibrillation mechanistic insights (paroxysmal vs. persistent status of atrial fibrillation and relationship with co-morbidities associated with atrial fibrillation).
Methods
123 patients underwent atrial late gadolinium enhancement imaging and electroanatomic voltage mapping prior to atrial fibrillation ablation. Atrial late gadolinium enhancement imaging was assessed with CEMRG software and electroanatomic voltage mapping processed with OpenEP software using previously published thresholds. Low voltage tissue was defined at (1) <0.5mV, (2) <1.17mV, and (3) <1.3mV. Atrial fibrosis using late gadolinium enhancement was defined using four thresholds (1) signal intensity >3.3 standard deviations above the blood pool mean; (2) image intensity ratio (IIR) 1.2x blood pool mean; (3) IIR 1.32x blood pool mean; and (4) IIR 0.97x blood pool mean.
Results
Patients with persistent atrial fibrillation and those with CHA2DS2VaSc >2 had increased low voltage area for each of the thresholds tested, but there was no increase in atrial late gadolinium enhancement area at any of the imaging thresholds tested.
Increased atrial fibrosis using IIR>0.97 was independently associated with recurrence of atrial fibrillation (OR 1.05 (CI 1.01-1.09), p=0.009) in both univariate and multivariate analysis. Low voltage area <1.13mV and low voltage area <1.17mV were associated with increased risk of recurrence (OR 1.02 (CI 1.01-1.04), p=0.01, and OR 1.03 (CI 1.01-1.04), p=0.009) in univariate analysis but neither voltage threshold remained statistically significant in multivariate analysis controlling for clinical variables.
Conclusion
Increased fibrosis burden measured with atrial magnetic resonance imaging, but not with low voltage area, is independently associated with recurrence of atrial fibrillation following catheter ablation. However, increased low voltage area measured with electroanatomic mapping is associated with persistent atrial fibrillation status and CHADS2VaSc score. These findings support the use of magnetic resonance imaging for pre-procedure assessment and the use of electroanatomic mapping for intraprocedural mechanism-based assessment of atrial cardiomyopathy.
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Affiliation(s)
- I Sim
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - O Razeghi
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - JA Solis Lemus
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - R Mukherjee
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - D O’hare
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - L O’neill
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - I Kotadia
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - CH Roney
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - M Wright
- St Thomas’ Hospital, Cardiology, London, United Kingdom of Great Britain & Northern Ireland
| | - A Chiribiri
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - S Niederer
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - M O’neill
- Kings College London, Biomedical Engineering and Imaging Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - SE Williams
- University of Edinburgh, Edinburgh, United Kingdom of Great Britain & Northern Ireland
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20
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Elliott MK, Costa CM, Whitaker J, Gemmell P, Mehta VS, Sidhu BS, Gould J, Williams SE, O'Neill M, Razavi R, Niederer S, Bishop MJ, Rinaldi CA. Effect of scar and pacing location on repolarization in a porcine myocardial infarction model. Heart Rhythm O2 2022; 3:186-195. [PMID: 35496454 PMCID: PMC9043407 DOI: 10.1016/j.hroo.2022.01.008] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Background The effect of chronic ischemic scar on repolarization is unclear, with conflicting results from human and animal studies. An improved understanding of electrical remodeling within scar and border zone tissue may enhance substrate-guided ablation techniques for treatment of ventricular tachycardia. Computational modeling studies have suggested increased dispersion of repolarization during epicardial, but not endocardial, left ventricular pacing, in close proximity to scar. However, the effect of endocardial pacing near scar in vivo is unknown. Objective The purpose of this study was to investigate the effect of scar and pacing location on local repolarization in a porcine myocardial infarction model. Methods Six model pigs underwent late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging followed by electroanatomic mapping of the left ventricular endocardium. LGE-CMR images were registered to the anatomic shell and scar defined by LGE. Activation recovery intervals (ARIs), a surrogate for action potential duration, and local ARI gradients were calculated from unipolar electrograms within areas of late gadolinium enhancement (aLGE) and healthy myocardium. Results There was no significant difference between aLGE and healthy myocardium in mean ARI (304.20 ± 19.44 ms vs 300.59 ± 19.22 ms; P = .43), ARI heterogeneity (23.32 ± 11.43 ms vs 24.85 ± 12.99 ms; P = .54), or ARI gradients (6.18 ± 2.09 vs 5.66 ± 2.32 ms/mm; P = .39). Endocardial pacing distance from scar did not affect ARI gradients. Conclusion Our findings suggest that changes in ARI are not an intrinsic property of surviving myocytes within scar, and endocardial pacing close to scar does not affect local repolarization.
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Affiliation(s)
- Mark K Elliott
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Caroline Mendonca Costa
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Philip Gemmell
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Vishal S Mehta
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Baldeep S Sidhu
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Justin Gould
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Christopher A Rinaldi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
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21
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Kotadia ID, O’Dowling R, Aboagye A, Sim I, O’Hare D, Lemus-Solis JA, Roney CH, Dweck M, Chiribiri A, Plein S, Sztriha L, Scott P, Harrison J, Ramsay D, Birns J, Somerville P, Bhalla A, Niederer S, O’Neill M, Williams SE. Atrial CARdiac Magnetic resonance imaging in patients with embolic stroke of unknown source without documented Atrial Fibrillation (CARM-AF): Study design and clinical protocol. Heart Rhythm O2 2022; 3:196-203. [PMID: 35496458 PMCID: PMC9043416 DOI: 10.1016/j.hroo.2022.01.005] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background Initiation of anticoagulation therapy in ischemic stroke patients is contingent on a clinical diagnosis of atrial fibrillation (AF). Results from previous studies suggest thromboembolic risk may predate clinical manifestations of AF. Early identification of this cohort of patients may allow early initiation of anticoagulation and reduce the risk of secondary stroke. Objective This study aims to produce a substrate-based predictive model using cardiac magnetic resonance imaging (CMR) and baseline noninvasive electrocardiographic investigations to improve the identification of patients at risk of future thromboembolism. Methods CARM-AF is a prospective, multicenter, observational cohort study. Ninety-two patients will be recruited following an embolic stroke of unknown source (ESUS) and undergo atrial CMR followed by insertion of an implantable loop recorder (ILR) as per routine clinical care within 3 months of index stroke. Remote ILR follow-up will be used to allocate patients to a study or control group determined by the presence or absence of AF as defined by ILR monitoring. Results Baseline data collection, noninvasive electrocardiographic data analysis, and imaging postprocessing will be performed at the time of enrollment. Primary analysis will be performed following 12 months of continuous ILR monitoring, with interim and delayed analyses performed at 6 months and 2 and 3 years, respectively. Conclusion The CARM-AF Study will use atrial structural and electrocardiographic metrics to identify patients with AF, or at high risk of developing AF, who may benefit from early initiation of anticoagulation.
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Affiliation(s)
- Irum D. Kotadia
- King’s College London, London, United Kingdom
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Robert O’Dowling
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Akosua Aboagye
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Iain Sim
- King’s College London, London, United Kingdom
| | | | | | | | - Marc Dweck
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
| | | | - Sven Plein
- King’s College London, London, United Kingdom
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | | | - Paul Scott
- King’s College Hospital, London, United Kingdom
| | - James Harrison
- Princess Royal University Hospital, London, United Kingdom
| | - Deborah Ramsay
- Princess Royal University Hospital, London, United Kingdom
| | - Jonathan Birns
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Peter Somerville
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Ajay Bhalla
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | | | - Mark O’Neill
- King’s College London, London, United Kingdom
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Steven E. Williams
- King’s College London, London, United Kingdom
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
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22
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Roney CH, Sim I, Yu J, Beach M, Mehta A, Alonso Solis-Lemus J, Kotadia I, Whitaker J, Corrado C, Razeghi O, Vigmond E, Narayan SM, O’Neill M, Williams SE, Niederer SA. Predicting Atrial Fibrillation Recurrence by Combining Population Data and Virtual Cohorts of Patient-Specific Left Atrial Models. Circ Arrhythm Electrophysiol 2022; 15:e010253. [PMID: 35089057 PMCID: PMC8845531 DOI: 10.1161/circep.121.010253] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [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] [Accepted: 01/03/2022] [Indexed: 01/14/2023]
Abstract
BACKGROUND Current ablation therapy for atrial fibrillation is suboptimal, and long-term response is challenging to predict. Clinical trials identify bedside properties that provide only modest prediction of long-term response in populations, while patient-specific models in small cohorts primarily explain acute response to ablation. We aimed to predict long-term atrial fibrillation recurrence after ablation in large cohorts, by using machine learning to complement biophysical simulations by encoding more interindividual variability. METHODS Patient-specific models were constructed for 100 atrial fibrillation patients (43 paroxysmal, 41 persistent, and 16 long-standing persistent), undergoing first ablation. Patients were followed for 1 year using ambulatory ECG monitoring. Each patient-specific biophysical model combined differing fibrosis patterns, fiber orientation maps, electrical properties, and ablation patterns to capture uncertainty in atrial properties and to test the ability of the tissue to sustain fibrillation. These simulation stress tests of different model variants were postprocessed to calculate atrial fibrillation simulation metrics. Machine learning classifiers were trained to predict atrial fibrillation recurrence using features from the patient history, imaging, and atrial fibrillation simulation metrics. RESULTS We performed 1100 atrial fibrillation ablation simulations across 100 patient-specific models. Models based on simulation stress tests alone showed a maximum accuracy of 0.63 for predicting long-term fibrillation recurrence. Classifiers trained to history, imaging, and simulation stress tests (average 10-fold cross-validation area under the curve, 0.85±0.09; recall, 0.80±0.13; precision, 0.74±0.13) outperformed those trained to history and imaging (area under the curve, 0.66±0.17) or history alone (area under the curve, 0.61±0.14). CONCLUSION A novel computational pipeline accurately predicted long-term atrial fibrillation recurrence in individual patients by combining outcome data with patient-specific acute simulation response. This technique could help to personalize selection for atrial fibrillation ablation.
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Affiliation(s)
- Caroline H. Roney
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
- School of Engineering and Materials Science, Queen Mary University of London, United Kingdom (C.H.R.)
| | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Jin Yu
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Marianne Beach
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Arihant Mehta
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Jose Alonso Solis-Lemus
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Irum Kotadia
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
- The Department of Internal Medicine, Cardiovascular Division, Brigham and Women’s Hospital, Boston, MA (J.W.)
| | - Cesare Corrado
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Orod Razeghi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Edward Vigmond
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, France (E.V.)
- Univ. Bordeaux, IMB, UMR 5251, F-33400 Talence, France (E.V.)
| | - Sanjiv M. Narayan
- Department of Medicine and Cardiovascular Institute, Stanford University, Palo Alto, CA (S.M.N.)
| | - Mark O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
- Centre for Cardiovascular Science, College of Medicine and Veterinary Medicine, University of Edinburgh (S.E.W.)
| | - Steven A. Niederer
- School of Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (C.H.R., I.S., J.Y., M.B., A.M., J.A.S.-L., I.K., J.W., C.C., O.R., M.O., S.E.W., S.A.N.)
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Roney CH, Sillett C, Whitaker J, Lemus JAS, Sim I, Kotadia I, O'Neill M, Williams SE, Niederer SA. Applications of multimodality imaging for left atrial catheter ablation. Eur Heart J Cardiovasc Imaging 2021; 23:31-41. [PMID: 34747450 PMCID: PMC8685603 DOI: 10.1093/ehjci/jeab205] [Citation(s) in RCA: 6] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Indexed: 11/13/2022] Open
Abstract
Atrial arrhythmias, including atrial fibrillation and atrial flutter, may be treated through catheter ablation. The process of atrial arrhythmia catheter ablation, which includes patient selection, pre-procedural planning, intra-procedural guidance, and post-procedural assessment, is typically characterized by the use of several imaging modalities to sequentially inform key clinical decisions. Increasingly, advanced imaging modalities are processed via specialized image analysis techniques and combined with intra-procedural electrical measurements to inform treatment approaches. Here, we review the use of multimodality imaging for left atrial ablation procedures. The article first outlines how imaging modalities are routinely used in the peri-ablation period. We then describe how advanced imaging techniques may inform patient selection for ablation and ablation targets themselves. Ongoing research directions for improving catheter ablation outcomes by using imaging combined with advanced analyses for personalization of ablation targets are discussed, together with approaches for their integration in the standard clinical environment. Finally, we describe future research areas with the potential to improve catheter ablation outcomes.
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Affiliation(s)
- Caroline H Roney
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - Charles Sillett
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | | | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - Irum Kotadia
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
- Centre for Cardiovascular Science, The University of Edinburgh, Scotland, UK
| | - Steven A Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
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24
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Qian S, Connolly A, Mendonca-Costa C, Campos F, Williams SE, Whitaker J, Rinaldi CA, Bishop MJ. An in-silico assessment of efficacy of two novel intra-cardiac electrode configurations versus traditional anti-tachycardia pacing therapy for terminating sustained ventricular tachycardia. Comput Biol Med 2021; 139:104987. [PMID: 34741904 PMCID: PMC8669079 DOI: 10.1016/j.compbiomed.2021.104987] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/24/2021] [Accepted: 10/24/2021] [Indexed: 11/06/2022]
Abstract
The implanted cardioverter defibrillator (ICD) is an effective direct therapy for the treatment of cardiac arrhythmias, including ventricular tachycardia (VT). Anti-tachycardia pacing (ATP) is often applied by the ICD as the first mode of therapy, but is often found to be ineffective, particularly for fast VTs. In such cases, strong, painful and damaging backup defibrillation shocks are applied by the device. Here, we propose two novel electrode configurations: "bipolar" and "transmural" which both combine the concept of targeted shock delivery with the advantage of reduced energy required for VT termination. We perform an in silico study to evaluate the efficacy of VT termination by applying one single (low-energy) monophasic shock from each novel configuration, comparing with conventional ATP therapy. Both bipolar and transmural configurations are able to achieve a higher efficacy (93% and 85%) than ATP (45%), with energy delivered similar to and two orders of magnitudes smaller than conventional ICD defibrillation shocks, respectively. Specifically, the transmural configuration (which applies the shock vector directly across the scar substrate sustaining the VT) is most efficient, requiring typically less than 1 J shock energy to achieve a high efficacy. The efficacy of both bipolar and transmural configurations are higher when applied to slow VTs (100% and 97%) compared to fast VTs (57% and 29%). Both novel electrode configurations introduced are able to improve electrotherapy efficacy while reducing the overall number of required therapies and need for strong backup shocks.
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Affiliation(s)
- Shuang Qian
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom.
| | - Adam Connolly
- Invicro, Burlington Danes Building, Du Cane Rd, London, W12 0N, United Kingdom
| | - Caroline Mendonca-Costa
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - Fernando Campos
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom; Department of Cardiology, Guy's and St Thomas' Hospital, London, SE1 7EH, United Kingdom
| | - Christopher A Rinaldi
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom; Department of Cardiology, Guy's and St Thomas' Hospital, London, SE1 7EH, United Kingdom
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, King's College London, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
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25
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Whitaker J, Neji R, Kim S, Connolly A, Aubriot T, Calvo JJ, Karim R, Roney CH, Murfin B, Richardson C, Morgan S, Ismail TF, Harrison J, de Vos J, Aalders MCG, Williams SE, Mukherjee R, O'Neill L, Chubb H, Tschabrunn C, Anter E, Camporota L, Niederer S, Roujol S, Bishop MJ, Wright M, Silberbauer J, Razavi R, O'Neill M. Late Gadolinium Enhancement Cardiovascular Magnetic Resonance Assessment of Substrate for Ventricular Tachycardia With Hemodynamic Compromise. Front Cardiovasc Med 2021; 8:744779. [PMID: 34765656 PMCID: PMC8576410 DOI: 10.3389/fcvm.2021.744779] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 07/20/2021] [Accepted: 09/20/2021] [Indexed: 11/13/2022] Open
Abstract
Background: The majority of data regarding tissue substrate for post myocardial infarction (MI) VT has been collected during hemodynamically tolerated VT, which may be distinct from the substrate responsible for VT with hemodynamic compromise (VT-HC). This study aimed to characterize tissue at diastolic locations of VT-HC in a porcine model. Methods: Late Gadolinium Enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging was performed in eight pigs with healed antero-septal infarcts. Seven pigs underwent electrophysiology study with venous arterial-extra corporeal membrane oxygenation (VA-ECMO) support. Tissue thickness, scar and heterogeneous tissue (HT) transmurality were calculated at the location of the diastolic electrograms of mapped VT-HC. Results: Diastolic locations had median scar transmurality of 33.1% and a median HT transmurality 7.6%. Diastolic activation was found within areas of non-transmural scar in 80.1% of cases. Tissue activated during the diastolic component of VT circuits was thinner than healthy tissue (median thickness: 5.5 mm vs. 8.2 mm healthy tissue, p < 0.0001) and closer to HT (median distance diastolic tissue: 2.8 mm vs. 11.4 mm healthy tissue, p < 0.0001). Non-scarred regions with diastolic activation were closer to steep gradients in thickness than non-scarred locations with normal EGMs (diastolic locations distance = 1.19 mm vs. 9.67 mm for non-diastolic locations, p < 0.0001). Sites activated late in diastole were closest to steep gradients in tissue thickness. Conclusions: Non-transmural scar, mildly decreased tissue thickness, and steep gradients in tissue thickness represent the structural characteristics of the diastolic component of reentrant circuits in VT-HC in this porcine model and could form the basis for imaging criteria to define ablation targets in future trials.
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Affiliation(s)
- John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom.,Siemens Healthcare, Frimley, United Kingdom
| | - Steven Kim
- Abbott Medical, St Paul, MN, United States
| | - Adam Connolly
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | | | - Justo Juliá Calvo
- Brighton and Sussex University Hospitals NHS Trust, Brighton, United Kingdom
| | - Rashed Karim
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Caroline H Roney
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Brendan Murfin
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Carla Richardson
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Stephen Morgan
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Tevfik F Ismail
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom.,Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - James Harrison
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Judith de Vos
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Maurice C G Aalders
- Department of Biomedical Engineering and Physics, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom.,Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Rahul Mukherjee
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Louisa O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Henry Chubb
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Cory Tschabrunn
- Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Elad Anter
- Cleveland Clinic, Cleveland, OH, United States
| | - Luigi Camporota
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Sébastien Roujol
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Matthew Wright
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - John Silberbauer
- Brighton and Sussex University Hospitals NHS Trust, Brighton, United Kingdom
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College, London, United Kingdom
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26
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Roney CH, Child N, Porter B, Sim I, Whitaker J, Clayton RH, Laughner JI, Shuros A, Neuzil P, Williams SE, Razavi RS, O'Neill M, Rinaldi CA, Taggart P, Wright M, Gill JS, Niederer SA. Time-Averaged Wavefront Analysis Demonstrates Preferential Pathways of Atrial Fibrillation, Predicting Pulmonary Vein Isolation Acute Response. Front Physiol 2021; 12:707189. [PMID: 34646149 PMCID: PMC8503618 DOI: 10.3389/fphys.2021.707189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 05/09/2021] [Accepted: 08/24/2021] [Indexed: 11/13/2022] Open
Abstract
Electrical activation during atrial fibrillation (AF) appears chaotic and disorganised, which impedes characterisation of the underlying substrate and treatment planning. While globally chaotic, there may be local preferential activation pathways that represent potential ablation targets. This study aimed to identify preferential activation pathways during AF and predict the acute ablation response when these are targeted by pulmonary vein isolation (PVI). In patients with persistent AF (n = 14), simultaneous biatrial contact mapping with basket catheters was performed pre-ablation and following each ablation strategy (PVI, roof, and mitral lines). Unipolar wavefront activation directions were averaged over 10 s to identify preferential activation pathways. Clinical cases were classified as responders or non-responders to PVI during the procedure. Clinical data were augmented with a virtual cohort of 100 models. In AF pre-ablation, pathways originated from the pulmonary vein (PV) antra in PVI responders (7/7) but not in PVI non-responders (6/6). We proposed a novel index that measured activation waves from the PV antra into the atrial body. This index was significantly higher in PVI responders than non-responders (clinical: 16.3 vs. 3.7%, p = 0.04; simulated: 21.1 vs. 14.1%, p = 0.02). Overall, this novel technique and proof of concept study demonstrated that preferential activation pathways exist during AF. Targeting patient-specific activation pathways that flowed from the PV antra to the left atrial body using PVI resulted in AF termination during the procedure. These PV activation flow pathways may correspond to the presence of drivers in the PV regions.
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Affiliation(s)
- Caroline H. Roney
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Nicholas Child
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Bradley Porter
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Richard H. Clayton
- INSIGNEO Institute for In Silico Medicine and Department of Computer Science, University of Sheffield, Sheffield, United Kingdom
| | | | - Allan Shuros
- Boston Scientific Corp, St. Paul, MN, United States
| | - Petr Neuzil
- Department of Cardiology, Na Holmolce Hospital, Prague, Czechia
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Reza S. Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | | | - Peter Taggart
- Institute of Cardiovascular Science, University College London, London, United Kingdom
| | - Matt Wright
- Department of Cardiology, Guy's and St Thomas' Hospital, London, United Kingdom
| | - Jaswinder S. Gill
- Department of Cardiology, Guy's and St Thomas' Hospital, London, United Kingdom
| | - Steven A. Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
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27
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Roney CH, Sim I, Yu J, Beach M, Mehta A, Solis-Lemus J, Kotadia I, Whitaker J, Razeghi O, Vigmond EJ, Narayan SM, O'Neill MD, Williams SE, Niederer SA. B-PO05-012 PREDICTING ATRIAL FIBRILLATION RECURRENCE BY COMBINING POPULATION DATA & PATIENT-SPECIFIC MODELING. Heart Rhythm 2021. [DOI: 10.1016/j.hrthm.2021.06.932] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Shen S, Niederer SA, Williams SE, Whitaker J, Bongiorni, Campbell S. B-PO04-128 FUNCTIONAL EFFECTS OF GAMMA RADIATION ON HUMAN CARDIOMYOCYTES. Heart Rhythm 2021. [DOI: 10.1016/j.hrthm.2021.06.822] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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29
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Godinez F, Tomi-Tricot R, Delcey M, Williams SE, Mooiweer R, Quesson B, Razavi R, Hajnal JV, Malik SJ. Interventional cardiac MRI using an add-on parallel transmit MR system: In vivo experience in sheep. Magn Reson Med 2021; 86:3360-3372. [PMID: 34286866 DOI: 10.1002/mrm.28931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/15/2021] [Accepted: 06/28/2021] [Indexed: 12/19/2022]
Abstract
PURPOSE We present in vivo testing of a parallel transmit system intended for interventional MR-guided cardiac procedures. METHODS The parallel transmit system was connected in-line with a conventional 1.5 Tesla MRI system to transmit and receive on an 8-coil array. The system used a current sensor for real-time feedback to achieve real-time current control by determining coupling and null modes. Experiments were conducted on 4 Charmoise sheep weighing 33.9-45.0 kg with nitinol guidewires placed under X-ray fluoroscopy in the atrium or ventricle of the heart via the femoral vein. Heating tests were done in vivo and post-mortem with a high RF power imaging sequence using the coupling mode. Anatomical imaging was done using a combination of null modes optimized to produce a useable B1 field in the heart. RESULTS Anatomical imaging produced cine images of the heart comparable in quality to imaging with the quad mode (all channels with the same amplitude and phase). Maximum observed temperature increases occurred when insulation was stripped from the wire tip. These were 4.1℃ and 0.4℃ for the coupling mode and null modes, respectively for the in vivo case; increasing to 6.0℃ and 1.3℃, respectively for the ex vivo case, because cooling from blood flow is removed. Heating < 0.1℃ was observed when insulation was not stripped from guidewire tips. In all tests, the parallel transmit system managed to reduce the temperature at the guidewire tip. CONCLUSION We have demonstrated the first in vivo usage of an auxiliary parallel transmit system employing active feedback-based current control for interventional MRI with a conventional MRI scanner.
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Affiliation(s)
- Felipe Godinez
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Raphael Tomi-Tricot
- MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom
| | - Marylène Delcey
- Centre de Recherche Cardio, Thoracique de Bordeaux/IHU Liryc, INSERM U1045-University of Bordeaux, Pessac, France.,Siemens Healthcare, Saint-Denis, France
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Ronald Mooiweer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Bruno Quesson
- Centre de Recherche Cardio, Thoracique de Bordeaux/IHU Liryc, INSERM U1045-University of Bordeaux, Pessac, France
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Joseph V Hajnal
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Shaihan J Malik
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
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30
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Kotadia ID, Sim I, Mukherjee R, O’Hare D, Chiribiri A, Birns J, Bhalla A, O’Neill M, Williams SE. Secondary Stroke Prevention Following Embolic Stroke of Unknown Source in the Absence of Documented Atrial Fibrillation: A Clinical Review. J Am Heart Assoc 2021; 10:e021045. [PMID: 34212774 PMCID: PMC8403300 DOI: 10.1161/jaha.121.021045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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] [Indexed: 11/25/2022]
Abstract
Approximately one-third of ischemic strokes are classified as cryptogenic strokes. The risk of stroke recurrence in these patients is significantly elevated with up to one-third of patients with cryptogenic stroke experiencing a further stroke within 10 years. While anticoagulation is the mainstay of treatment for secondary stroke prevention in the context of documented atrial fibrillation (AF), it is estimated that up to 25% of patients with cryptogenic stroke have undiagnosed AF. Furthermore, the historical acceptance of a causal relationship between AF and stroke has recently come under scrutiny, with evidence to suggest that embolic stroke risk may be elevated even in the absence of documented atrial fibrillation attributable to the presence of electrical and structural changes constituting an atrial cardiomyopathy. More recently, the term embolic stroke of unknown source has garnered increasing interest as a subset of patients with cryptogenic stroke in whom a minimum set of diagnostic investigations has been performed, and a nonlacunar infarct highly suspicious of embolic etiology is suspected but in the absence of an identifiable secondary cause of stroke. The ongoing ARCADIA (Atrial Cardiopathy and Antithrombotic Drugs in Prevention After Cryptogenic Stroke) randomized trial and ATTICUS (Apixiban for Treatment of Embolic Stroke of Undetermined Source) study seek to further define this novel term. This review summarizes the relationship between AF, embolic stroke, and atrial cardiomyopathy and provides an overview of the clinical relevance of cardiac imaging, electrocardiographic, and serum biomarkers in the assessment of AF and secondary stroke risk. The implications of these findings on therapeutic considerations is considered and gaps in the literature identified as areas for future study in risk stratifying this cohort of patients.
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Affiliation(s)
- Irum D. Kotadia
- King’s College LondonLondonUnited Kingdom
- Guy’s and St Thomas’ NHS Foundation TrustLondonUnited Kingdom
| | - Iain Sim
- King’s College LondonLondonUnited Kingdom
| | | | | | | | - Jonathan Birns
- Guy’s and St Thomas’ NHS Foundation TrustLondonUnited Kingdom
| | - Ajay Bhalla
- Guy’s and St Thomas’ NHS Foundation TrustLondonUnited Kingdom
| | - Mark O’Neill
- King’s College LondonLondonUnited Kingdom
- Guy’s and St Thomas’ NHS Foundation TrustLondonUnited Kingdom
| | - Steven E. Williams
- King’s College LondonLondonUnited Kingdom
- Centre for Cardiovascular ScienceUniversity of EdinburghUnited Kingdom
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31
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Williams SE, Roney CH, Connolly A, Sim I, Whitaker J, O’Hare D, Kotadia I, O’Neill L, Corrado C, Bishop M, Niederer SA, Wright M, O’Neill M, Linton NWF. OpenEP: A Cross-Platform Electroanatomic Mapping Data Format and Analysis Platform for Electrophysiology Research. Front Physiol 2021; 12:646023. [PMID: 33716795 PMCID: PMC7952326 DOI: 10.3389/fphys.2021.646023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 12/24/2020] [Accepted: 01/29/2021] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Electroanatomic mapping systems are used to support electrophysiology research. Data exported from these systems is stored in proprietary formats which are challenging to access and storage-space inefficient. No previous work has made available an open-source platform for parsing and interrogating this data in a standardized format. We therefore sought to develop a standardized, open-source data structure and associated computer code to store electroanatomic mapping data in a space-efficient and easily accessible manner. METHODS A data structure was defined capturing the available anatomic and electrical data. OpenEP, implemented in MATLAB, was developed to parse and interrogate this data. Functions are provided for analysis of chamber geometry, activation mapping, conduction velocity mapping, voltage mapping, ablation sites, and electrograms as well as visualization and input/output functions. Performance benchmarking for data import and storage was performed. Data import and analysis validation was performed for chamber geometry, activation mapping, voltage mapping and ablation representation. Finally, systematic analysis of electrophysiology literature was performed to determine the suitability of OpenEP for contemporary electrophysiology research. RESULTS The average time to parse clinical datasets was 400 ± 162 s per patient. OpenEP data was two orders of magnitude smaller than compressed clinical data (OpenEP: 20.5 ± 8.7 Mb, vs clinical: 1.46 ± 0.77 Gb). OpenEP-derived geometry metrics were correlated with the same clinical metrics (Area: R 2 = 0.7726, P < 0.0001; Volume: R 2 = 0.5179, P < 0.0001). Investigating the cause of systematic bias in these correlations revealed OpenEP to outperform the clinical platform in recovering accurate values. Both activation and voltage mapping data created with OpenEP were correlated with clinical values (mean voltage R 2 = 0.8708, P < 0.001; local activation time R 2 = 0.8892, P < 0.0001). OpenEP provides the processing necessary for 87 of 92 qualitatively assessed analysis techniques (95%) and 119 of 136 quantitatively assessed analysis techniques (88%) in a contemporary cohort of mapping studies. CONCLUSIONS We present the OpenEP framework for evaluating electroanatomic mapping data. OpenEP provides the core functionality necessary to conduct electroanatomic mapping research. We demonstrate that OpenEP is both space-efficient and accurately representative of the original data. We show that OpenEP captures the majority of data required for contemporary electroanatomic mapping-based electrophysiology research and propose a roadmap for future development.
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Affiliation(s)
- Steven E. Williams
- King’s College London, London, United Kingdom
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, United Kingdom
| | | | - Adam Connolly
- King’s College London, London, United Kingdom
- Invicro, Ltd., London, United Kingdom
| | - Iain Sim
- King’s College London, London, United Kingdom
| | | | | | | | | | | | | | | | - Matt Wright
- King’s College London, London, United Kingdom
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
| | - Mark O’Neill
- King’s College London, London, United Kingdom
- Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom
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32
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Nguyen T, Williams SE, Falkner G, Shetty AK. Cardiac resynchronization therapy pacemaker implant in a patient with ARTO mitral device in situ. Pacing Clin Electrophysiol 2021; 44:744-746. [PMID: 33432675 DOI: 10.1111/pace.14169] [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] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/19/2020] [Accepted: 01/10/2021] [Indexed: 11/29/2022]
Abstract
The ARTO device is a percutaneous device for functional mitral regurgitation composed of a transseptal anchor and a T-bar sitting in the coronary sinus which reduce the minor axis of the mitral valve. We present a case showing the technical feasibility of an LV lead implant in patients with an ARTO device in situ.
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Affiliation(s)
- Thomas Nguyen
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Steven E Williams
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Gillian Falkner
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Anoop K Shetty
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
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33
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O'Neill L, Floyd CN, Sim I, Whitaker J, Mukherjee R, O'Hare D, Gatzoulis M, Frigiola A, O'Neill MD, Williams SE. Percutaneous secundum atrial septal defect closure for the treatment of atrial arrhythmia in the adult: A meta-analysis. Int J Cardiol 2020; 321:104-112. [PMID: 32679141 DOI: 10.1016/j.ijcard.2020.07.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/24/2020] [Accepted: 07/08/2020] [Indexed: 11/20/2022]
Abstract
BACKGROUND Atrial arrhythmias are common in patients with atrial septal defects (ASD) but the effects of percutaneous closure on atrial arrhythmia prevalence is unclear. We investigated the effects of ASD device closure and the impact of age at time of closure on prevalent atrial arrythmia. METHODS Meta-analysis of studies reporting atrial arrhythmia prevalence in adult patients before and after percutaneous closure was performed. Primary outcomes were prevalence of 'all atrial arrhythmia' and atrial fibrillation alone post closure. Sub-group analysis examined the effects of closure according to age in patients; <40 years, ≥40 and ≥ 60 years. 25 studies were included. RESULTS Meta-analysis of all studies demonstrated no reduction in all atrial arrhythmia or atrial fibrillation prevalence post-closure (OR 0.855, 95% CI 0.672 to 1.087, P = .201 and OR 0.818, 95% CI 0.645 to 1.038, P = .099, respectively). A weak reduction in all atrial arrhythmia and atrial fibrillation was seen in patients ≥40 years (OR 0.77, 95% CI 0.616 to 0.979, P = .032 and OR 0.760, 95% CI 0.6 to 0.964, P = .024, respectively) but not ≥60 years (OR 0.822, 95% CI 0.593 to 1.141, P = .242 and OR 0.83, 95% CI 0.598 to 1.152, P = .266, respectively). No data were available in patients <40 years. This, and other limitations, prevents conclusive assessment of the effect of age on arrhythmia prevalence. CONCLUSIONS Overall, percutaneous ASD closure is not associated with a reduction in atrial arrhythmia prevalence in this meta-analysis. A weak benefit is seen in patients ≥40 years of age, not present in patients ≥60 years.
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Affiliation(s)
| | - Christopher N Floyd
- King's College London, London, United Kingdom; Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Iain Sim
- King's College London, London, United Kingdom
| | | | | | | | - Michael Gatzoulis
- Royal Brompton Hospital, London, United Kingdom; National Heart and Lung Institute, Imperial College, London, United Kingdom
| | | | | | - Steven E Williams
- King's College London, London, United Kingdom; Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
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34
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Razeghi O, Sim I, Roney CH, Karim R, Chubb H, Whitaker J, O’Neill L, Mukherjee R, Wright M, O’Neill M, Williams SE, Niederer S. Fully Automatic Atrial Fibrosis Assessment Using a Multilabel Convolutional Neural Network. Circ Cardiovasc Imaging 2020; 13:e011512. [PMID: 33317334 PMCID: PMC7771635 DOI: 10.1161/circimaging.120.011512] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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] [Indexed: 11/16/2022]
Abstract
Supplemental Digital Content is available in the text. Background: Pathological atrial fibrosis is a major contributor to sustained atrial fibrillation. Currently, late gadolinium enhancement (LGE) scans provide the only noninvasive estimate of atrial fibrosis. However, widespread adoption of atrial LGE has been hindered partly by nonstandardized image processing techniques, which can be operator and algorithm dependent. Minimal validation and limited access to transparent software platforms have also exacerbated the problem. This study aims to estimate atrial fibrosis from cardiac magnetic resonance scans using a reproducible operator-independent fully automatic open-source end-to-end pipeline. Methods: A multilabel convolutional neural network was designed to accurately delineate atrial structures including the blood pool, pulmonary veins, and mitral valve. The output from the network removed the operator dependent steps in a reproducible pipeline and allowed for automated estimation of atrial fibrosis from LGE-cardiac magnetic resonance scans. The pipeline results were compared against manual fibrosis burdens, calculated using published thresholds: image intensity ratio 0.97, image intensity ratio 1.61, and mean blood pool signal +3.3 SD. Results: We validated our methods on a large 3-dimensional LGE-cardiac magnetic resonance data set from 207 labeled scans. Automatic atrial segmentation achieved a 91% Dice score, compared with the mutual agreement of 85% in Dice seen in the interobserver analysis of operators. Intraclass correlation coefficients of the automatic pipeline with manually generated results were excellent and better than or equal to interobserver correlations for all 3 thresholds: 0.94 versus 0.88, 0.99 versus 0.99, 0.99 versus 0.96 for image intensity ratio 0.97, image intensity ratio 1.61, and +3.3 SD thresholds, respectively. Automatic analysis required 3 minutes per case on a standard workstation. The network and the analysis software are publicly available. Conclusions: Our pipeline provides a fully automatic estimation of fibrosis burden from LGE-cardiac magnetic resonance scans that is comparable to manual analysis. This removes one key source of variability in the measurement of atrial fibrosis.
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Affiliation(s)
- Orod Razeghi
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Iain Sim
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Caroline H. Roney
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Rashed Karim
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Henry Chubb
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - John Whitaker
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Louisa O’Neill
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Rahul Mukherjee
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Matthew Wright
- Cardiology Department, St. Thomas’ Hospital, London, United Kingdom (M.W., M.O.)
| | - Mark O’Neill
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
- Cardiology Department, St. Thomas’ Hospital, London, United Kingdom (M.W., M.O.)
| | - Steven E. Williams
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
| | - Steven Niederer
- Biomedical Engineering and Imaging Sciences, King’s College London, United Kingdom (O.R., I.S., C.H.R., R.K., H.C., J.W., L.O., R.M., M.O., S.E.W., S.N.)
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35
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O'Neill MD, Williams SE. Intentions and consequences: Power applied and current delivered during radiofrequency ablation. J Cardiovasc Electrophysiol 2020; 31:2846-2847. [PMID: 32762061 DOI: 10.1111/jce.14706] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 07/27/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Mark D O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
- Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Steven E Williams
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
- Guy's and St Thomas' NHS Foundation Trust, London, UK
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36
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O'Neill L, Karim R, Mukherjee RK, Whitaker J, Sim I, Harrison J, Razeghi O, Niederer S, Ismail T, Wright M, O'Neill MD, Williams SE. Pulmonary vein encirclement using an Ablation Index-guided point-by-point workflow: cardiovascular magnetic resonance assessment of left atrial scar formation. Europace 2020; 21:1817-1823. [PMID: 31793653 PMCID: PMC6887923 DOI: 10.1093/europace/euz226] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [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: 04/18/2019] [Accepted: 07/24/2019] [Indexed: 11/12/2022] Open
Abstract
AIMS A point-by-point workflow for pulmonary vein isolation (PVI) targeting pre-defined Ablation Index values (a composite of contact force, time, and power) and minimizing interlesion distance may optimize the creation of contiguous ablation lesions whilst minimizing scar formation. We aimed to compare ablation scar formation in patients undergoing PVI using this workflow to patients undergoing a continuous catheter drag workflow. METHODS AND RESULTS Post-ablation cardiovascular magnetic resonance imaging was performed in patients undergoing 1st-time PVI using a parameter-guided point-by-point workflow (n = 26). Total left atrial scar burden and the width and continuity of the pulmonary vein encirclement were determined on analysis of atrial late gadolinium enhancement sequences. Comparison was made with a cohort of patients (n = 20) undergoing PVI using continuous drag lesions. Mean post-ablation scar burden and scar width were significantly lower in the point-by-point group than in the control group (6.6 ± 6.8% vs. 9.6 ± 5.0%, P = 0.03 and 7.9 ± 3.6 mm vs. 10.7 ± 2.3 mm, P = 0.003). More complete bilateral pulmonary vein encirclements were seen in the point-by-point group (P = 0.038). All patients achieved acute PVI. CONCLUSION Pulmonary vein isolation using a point-by-point workflow is feasible and results in a lower scar burden and scar width with more complete pulmonary vein encirclements than a conventional drag lesion approach.
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Affiliation(s)
- Louisa O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - Rashed Karim
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - Rahul K Mukherjee
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, UK
| | - Iain Sim
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - James Harrison
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - Orod Razeghi
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - Steven Niederer
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK
| | - Tevfik Ismail
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, UK
| | - Matthew Wright
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, UK
| | - Mark D O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, UK
| | - Steven E Williams
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London SE1 7EH, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, UK
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Roney CH, Beach ML, Mehta AM, Sim I, Corrado C, Bendikas R, Solis-Lemus JA, Razeghi O, Whitaker J, O’Neill L, Plank G, Vigmond E, Williams SE, O’Neill MD, Niederer SA. In silico Comparison of Left Atrial Ablation Techniques That Target the Anatomical, Structural, and Electrical Substrates of Atrial Fibrillation. Front Physiol 2020; 11:1145. [PMID: 33041850 PMCID: PMC7526475 DOI: 10.3389/fphys.2020.572874] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [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: 06/15/2020] [Accepted: 08/18/2020] [Indexed: 12/17/2022] Open
Abstract
Catheter ablation therapy for persistent atrial fibrillation (AF) typically includes pulmonary vein isolation (PVI) and may include additional ablation lesions that target patient-specific anatomical, electrical, or structural features. Clinical centers employ different ablation strategies, which use imaging data together with electroanatomic mapping data, depending on data availability. The aim of this study was to compare ablation techniques across a virtual cohort of AF patients. We constructed 20 paroxysmal and 30 persistent AF patient-specific left atrial (LA) bilayer models incorporating fibrotic remodeling from late-gadolinium enhancement (LGE) MRI scans. AF was simulated and post-processed using phase mapping to determine electrical driver locations over 15 s. Six different ablation approaches were tested: (i) PVI alone, modeled as wide-area encirclement of the pulmonary veins; PVI together with: (ii) roof and inferior lines to model posterior wall box isolation; (iii) isolating the largest fibrotic area (identified by LGE-MRI); (iv) isolating all fibrotic areas; (v) isolating the largest driver hotspot region [identified as high simulated phase singularity (PS) density]; and (vi) isolating all driver hotspot regions. Ablation efficacy was assessed to predict optimal ablation therapies for individual patients. We subsequently trained a random forest classifier to predict ablation response using (a) imaging metrics alone, (b) imaging and electrical metrics, or (c) imaging, electrical, and ablation lesion metrics. The optimal ablation approach resulting in termination, or if not possible atrial tachycardia (AT), varied among the virtual patient cohort: (i) 20% PVI alone, (ii) 6% box ablation, (iii) 2% largest fibrosis area, (iv) 4% all fibrosis areas, (v) 2% largest driver hotspot, and (vi) 46% all driver hotspots. Around 20% of cases remained in AF for all ablation strategies. The addition of patient-specific and ablation pattern specific lesion metrics to the trained random forest classifier improved predictive capability from an accuracy of 0.73 to 0.83. The trained classifier results demonstrate that the surface areas of pre-ablation driver regions and of fibrotic tissue not isolated by the proposed ablation strategy are both important for predicting ablation outcome. Overall, our study demonstrates the need to select the optimal ablation strategy for each patient. It suggests that both patient-specific fibrosis properties and driver locations are important for planning ablation approaches, and the distribution of lesions is important for predicting an acute response.
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Affiliation(s)
- Caroline H. Roney
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Marianne L. Beach
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Arihant M. Mehta
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Cesare Corrado
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Rokas Bendikas
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Jose A. Solis-Lemus
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Orod Razeghi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Louisa O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Gernot Plank
- Department of Biophysics, Medical University of Graz, Graz, Austria
| | - Edward Vigmond
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Bordeaux, France
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Mark D. O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
| | - Steven A. Niederer
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London, United Kingdom
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38
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Solís-Lemus JA, Costar E, Doorly D, Kerrigan EC, Kennedy CH, Tait F, Niederer S, Vincent PE, Williams SE. A simulated single ventilator/dual patient ventilation strategy for acute respiratory distress syndrome during the COVID-19 pandemic. R Soc Open Sci 2020; 7:200585. [PMID: 32968521 PMCID: PMC7481711 DOI: 10.1098/rsos.200585] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 04/06/2020] [Accepted: 08/12/2020] [Indexed: 06/11/2023]
Abstract
The potential for acute shortages of ventilators at the peak of the COVID-19 pandemic has raised the possibility of needing to support two patients from a single ventilator. To provide a system for understanding and prototyping designs, we have developed a mathematical model of two patients supported by a mechanical ventilator. We propose a standard set-up where we simulate the introduction of T-splitters to supply air to two patients and a modified set-up where we introduce a variable resistance in each inhalation pathway and one-way valves in each exhalation pathway. Using the standard set-up, we demonstrate that ventilating two patients with mismatched lung compliances from a single ventilator will lead to clinically significant reductions in tidal volume in the patient with the lowest respiratory compliance. Using the modified set-up, we demonstrate that it could be possible to achieve the same tidal volumes in two patients with mismatched lung compliances, and we show that the tidal volume of one patient can be manipulated independently of the other. The results indicate that, with appropriate modifications, two patients could be supported from a single ventilator with independent control of tidal volumes.
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Affiliation(s)
- José A. Solís-Lemus
- School of Biomedical Engineering and Imaging Sciences, King's College London, London WC2R 2LS, UK
| | | | - Denis Doorly
- Department of Aeronautics, Imperial College London, UK
| | - Eric C. Kerrigan
- Department of Aeronautics, Imperial College London, UK
- Department of Electrical and Electronic Engineering, Imperial College London, UK
| | | | | | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London WC2R 2LS, UK
| | | | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London WC2R 2LS, UK
- Department of Cardiology, Guy's and St Thomas’ NHS Foundation Trust, UK
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Coveney S, Corrado C, Roney CH, O’Hare D, Williams SE, O’Neill MD, Niederer SA, Clayton RH, Oakley JE, Wilkinson RD. Gaussian process manifold interpolation for probabilistic atrial activation maps and uncertain conduction velocity. Philos Trans A Math Phys Eng Sci 2020; 378:20190345. [PMID: 32448072 PMCID: PMC7287339 DOI: 10.1098/rsta.2019.0345] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/21/2020] [Indexed: 05/21/2023]
Abstract
In patients with atrial fibrillation, local activation time (LAT) maps are routinely used for characterizing patient pathophysiology. The gradient of LAT maps can be used to calculate conduction velocity (CV), which directly relates to material conductivity and may provide an important measure of atrial substrate properties. Including uncertainty in CV calculations would help with interpreting the reliability of these measurements. Here, we build upon a recent insight into reduced-rank Gaussian processes (GPs) to perform probabilistic interpolation of uncertain LAT directly on human atrial manifolds. Our Gaussian process manifold interpolation (GPMI) method accounts for the topology of the atrium, and allows for calculation of statistics for predicted CV. We demonstrate our method on two clinical cases, and perform validation against a simulated ground truth. CV uncertainty depends on data density, wave propagation direction and CV magnitude. GPMI is suitable for probabilistic interpolation of other uncertain quantities on non-Euclidean manifolds. This article is part of the theme issue 'Uncertainty quantification in cardiac and cardiovascular modelling and simulation'.
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Affiliation(s)
- Sam Coveney
- Insigneo Institute for in-silico medicine and Department of Computer Science, University of Sheffield, Sheffield, UK
- e-mail:
| | - Cesare Corrado
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Caroline H. Roney
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Daniel O’Hare
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Steven E. Williams
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Mark D. O’Neill
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Steven A. Niederer
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Richard H. Clayton
- Insigneo Institute for in-silico medicine and Department of Computer Science, University of Sheffield, Sheffield, UK
| | - Jeremy E. Oakley
- School of Mathematics and Statistics, University of Sheffield, Sheffield, UK
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Abstract
High-power, short-duration (HPSD) ablation for the treatment of AF is emerging as an alternative to ablation using conventional ablation generator settings characterised by lower power and longer duration. Although the reported potential advantages of HPSD ablation include less tissue oedema and collateral tissue damage, a reduction in procedural time and superior ablation lesion formation, clinical studies of HPSD ablation validating these observations are limited. One of the main challenges for HPSD ablation has been the inability to adequately assess temperature and lesion formation in real time. Novel catheter designs may improve the accuracy of intra-ablation temperature recording and correspondingly may improve the safety profile of HPSD ablation. Clinical studies of HPSD ablation are on-going and interpretation of the data from these and other studies will be required to ascertain the clinical value of HPSD ablation.
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Affiliation(s)
| | | | - Mark O'Neill
- Guy's and St Thomas' NHS Foundation Trust, London, UK
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Coveney S, Corrado C, Roney CH, Wilkinson RD, Oakley JE, Lindgren F, Williams SE, O'Neill MD, Niederer SA, Clayton RH. Probabilistic Interpolation of Uncertain Local Activation Times on Human Atrial Manifolds. IEEE Trans Biomed Eng 2020; 67:99-109. [PMID: 30969911 DOI: 10.1109/tbme.2019.2908486] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Local activation time (LAT) mapping of the atria is important for targeted treatment of atrial arrhythmias, but current methods do not interpolate on the atrial manifold and neglect uncertainties associated with LAT observations. In this paper, we describe novel methods to, first, quantify uncertainties in LAT arising from bipolar electrogram analysis and assignment of electrode recordings to the anatomical mesh, second, interpolate uncertain LAT measurements directly on left atrial manifolds to obtain complete probabilistic activation maps, and finally, interpolate LAT jointly across both the manifold and different S1-S2 pacing protocols. METHODS A modified center of mass approach was used to process bipolar electrograms, yielding a LAT estimate and error distribution from the electrogram morphology. An error distribution for assigning measurements to the anatomical mesh was estimated. Probabilistic LAT maps were produced by interpolating on a left atrial manifold using Gaussian Markov random fields, taking into account observation errors and characterizing LAT predictions by their mean and standard deviation. This approach was extended to interpolate across S1-S2 pacing protocols. RESULTS We evaluated our approach using recordings from three patients undergoing atrial ablation. Cross-validation showed consistent and accurate prediction of LAT observations both at different locations on the left atrium and for different S1-S2 intervals. SIGNIFICANCE Interpolation of scalar and vector fields across anatomical structures from point measurements is a challenging problem in biomedical engineering, compounded by uncertainties in measurements and meshes. New methods and approaches are required, and in this paper, we have demonstrated an effective method for probabilistic interpolation of uncertain LAT.
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Abstract
Supraventricular tachycardia (SVT) is a common cause of hospital admissions and can cause significant patient discomfort and distress. The most common SVTs include atrioventricular nodal re-entrant tachycardia, atrioventricular re-entrant tachycardia and atrial tachycardia. In many cases, the underlying mechanism can be deduced from electrocardiography during tachycardia, comparing it with sinus rhythm, and assessing the onset and offset of tachycardia. Recent European Society of Cardiology guidelines continue to advocate the use of vagal manoeuvres and adenosine as first-line therapies in the acute diagnosis and management of SVT. Alternative therapies include the use of beta-blockers and calcium channel blockers. All patients treated for SVT should be referred for a heart rhythm specialist opinion. Long-term treatment is dependent on several factors including frequency of symptoms, risk stratification, and patient preference. Management can range from conservative, if symptoms are rare and the patient is low risk, to catheter ablation which is curative in the majority of patients.
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Affiliation(s)
- Irum D Kotadia
- King's College London, London, UK and Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Steven E Williams
- King's College London, London, UK and Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Mark O'Neill
- King's College London, London, UK and Guy's and St Thomas' NHS Foundation Trust, London, UK
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43
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Whitaker J, Neji R, Byrne N, Puyol-Antón E, Mukherjee RK, Williams SE, Chubb H, O’Neill L, Razeghi O, Connolly A, Rhode K, Niederer S, King A, Tschabrunn C, Anter E, Nezafat R, Bishop MJ, O’Neill M, Razavi R, Roujol S. Improved co-registration of ex-vivo and in-vivo cardiovascular magnetic resonance images using heart-specific flexible 3D printed acrylic scaffold combined with non-rigid registration. J Cardiovasc Magn Reson 2019; 21:62. [PMID: 31597563 PMCID: PMC6785908 DOI: 10.1186/s12968-019-0574-z] [Citation(s) in RCA: 10] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 09/02/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Ex-vivo cardiovascular magnetic resonance (CMR) imaging has played an important role in the validation of in-vivo CMR characterization of pathological processes. However, comparison between in-vivo and ex-vivo imaging remains challenging due to shape changes occurring between the two states, which may be non-uniform across the diseased heart. A novel two-step process to facilitate registration between ex-vivo and in-vivo CMR was developed and evaluated in a porcine model of chronic myocardial infarction (MI). METHODS Seven weeks after ischemia-reperfusion MI, 12 swine underwent in-vivo CMR imaging with late gadolinium enhancement followed by ex-vivo CMR 1 week later. Five animals comprised the control group, in which ex-vivo imaging was undertaken without any support in the LV cavity, 7 animals comprised the experimental group, in which a two-step registration optimization process was undertaken. The first step involved a heart specific flexible 3D printed scaffold generated from in-vivo CMR, which was used to maintain left ventricular (LV) shape during ex-vivo imaging. In the second step, a non-rigid co-registration algorithm was applied to align in-vivo and ex-vivo data. Tissue dimension changes between in-vivo and ex-vivo imaging were compared between the experimental and control group. In the experimental group, tissue compartment volumes and thickness were compared between in-vivo and ex-vivo data before and after non-rigid registration. The effectiveness of the alignment was assessed quantitatively using the DICE similarity coefficient. RESULTS LV cavity volume changed more in the control group (ratio of cavity volume between ex-vivo and in-vivo imaging in control and experimental group 0.14 vs 0.56, p < 0.0001) and there was a significantly greater change in the short axis dimensions in the control group (ratio of short axis dimensions in control and experimental group 0.38 vs 0.79, p < 0.001). In the experimental group, prior to non-rigid co-registration the LV cavity contracted isotropically in the ex-vivo condition by less than 20% in each dimension. There was a significant proportional change in tissue thickness in the healthy myocardium (change = 29 ± 21%), but not in dense scar (change = - 2 ± 2%, p = 0.034). Following the non-rigid co-registration step of the process, the DICE similarity coefficients for the myocardium, LV cavity and scar were 0.93 (±0.02), 0.89 (±0.01) and 0.77 (±0.07) respectively and the myocardial tissue and LV cavity volumes had a ratio of 1.03 and 1.00 respectively. CONCLUSIONS The pattern of the morphological changes seen between the in-vivo and the ex-vivo LV differs between scar and healthy myocardium. A 3D printed flexible scaffold based on the in-vivo shape of the LV cavity is an effective strategy to minimize morphological changes in the ex-vivo LV. The subsequent non-rigid registration step further improved the co-registration and local comparison between in-vivo and ex-vivo data.
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Affiliation(s)
- John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
- Siemens Healthcare Limited, Frimley, UK
| | - Nicholas Byrne
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
- Medical Physics, Guy’s and St. Thomas’ NHS Foundation Trust, London, UK
| | - Esther Puyol-Antón
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Rahul K. Mukherjee
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Steven E. Williams
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Henry Chubb
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Louisa O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Orod Razeghi
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Adam Connolly
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Kawal Rhode
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Andrew King
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Cory Tschabrunn
- Cardiology Department, University of Pennsylvania, Philadelphia, PA USA
| | - Elad Anter
- Cardiology Department, Beth Israel Deaconess Medical Centre / Harvard Medical School, Boston, MA USA
| | - Reza Nezafat
- Cardiology Department, Beth Israel Deaconess Medical Centre / Harvard Medical School, Boston, MA USA
| | - Martin J. Bishop
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Mark O’Neill
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
| | - Sébastien Roujol
- School of Biomedical Engineering and Imaging Sciences, King’s College, London, Fourth Floor Lambeth Wing, St Thomas’ Hospital, London, SE1 7EH UK
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O'Neill L, Harrison J, Chubb H, Whitaker J, Mukherjee RK, Bloch LØ, Andersen NP, Dam H, Jensen HK, Niederer S, Wright M, O'Neill M, Williams SE. Voltage and pace-capture mapping of linear ablation lesions overestimates chronic ablation gap size. Europace 2019; 20:2028-2035. [PMID: 29701778 DOI: 10.1093/europace/euy062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/21/2018] [Indexed: 11/14/2022] Open
Abstract
Aims Conducting gaps in lesion sets are a major reason for failure of ablation procedures. Voltage mapping and pace-capture have been proposed for intra-procedural identification of gaps. We aimed to compare gap size measured acutely and chronically post-ablation to macroscopic gap size in a porcine model. Methods and results Intercaval linear ablation was performed in eight Göttingen minipigs with a deliberate gap of ∼5 mm left in the ablation line. Gap size was measured by interpolating ablation contact force values between ablation tags and thresholding at a low force cut-off of 5 g. Bipolar voltage mapping and pace-capture mapping along the length of the line were performed immediately, and at 2 months, post-ablation. Animals were euthanized and gap sizes were measured macroscopically. Voltage thresholds to define scar were determined by receiver operating characteristic analysis as <0.56 mV (acutely) and <0.62 mV (chronically). Taking the macroscopic gap size as gold standard, error in gap measurements were determined for voltage, pace-capture, and ablation contact force maps. All modalities overestimated chronic gap size, by 1.4 ± 2.0 mm (ablation contact force map), 5.1 ± 3.4 mm (pace-capture), and 9.5 ± 3.8 mm (voltage mapping). Error on ablation contact force map gap measurements were significantly less than for voltage mapping (P = 0.003, Tukey's multiple comparisons test). Chronically, voltage mapping and pace-capture mapping overestimated macroscopic gap size by 11.9 ± 3.7 and 9.8 ± 3.5 mm, respectively. Conclusion Bipolar voltage and pace-capture mapping overestimate the size of chronic gap formation in linear ablation lesions. The most accurate estimation of chronic gap size was achieved by analysis of catheter-myocardium contact force during ablation.
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Affiliation(s)
- Louisa O'Neill
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - James Harrison
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - Henry Chubb
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - Rahul K Mukherjee
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - Lars Ølgaard Bloch
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, MR Research Centre, Aarhus University Hospital, Aarhus, Denmark
| | | | - Høgni Dam
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Henrik K Jensen
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Health, Aarhus University Hospital, Aarhus, Denmark
| | - Steven Niederer
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
| | - Matthew Wright
- Cardiovascular Division, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Mark O'Neill
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK.,Cardiovascular Division, Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Steven E Williams
- Division of Imaging Sciences and Biomedical Imaging, King's College London, 4th Floor North Wing, St. Thomas' Hospital, London, UK
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Roney CH, Williams SE, Cochet H, Mukherjee RK, O'Neill L, Sim I, Whitaker J, Razeghi O, Klein GJ, Vigmond EJ, O'Neill M, Niederer SA. Patient-specific simulations predict efficacy of ablation of interatrial connections for treatment of persistent atrial fibrillation. Europace 2019; 20:iii55-iii68. [PMID: 30476055 PMCID: PMC6251187 DOI: 10.1093/europace/euy232] [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: 09/10/2018] [Accepted: 10/12/2018] [Indexed: 11/23/2022] Open
Abstract
Aims Treatments for persistent atrial fibrillation (AF) offer limited efficacy. One potential strategy aims to return the right atrium (RA) to sinus rhythm (SR) by ablating interatrial connections (IAC) to isolate the atria, but there is limited clinical data to evaluate this ablation approach. We aimed to use simulation to evaluate and predict patient-specific suitability for ablation of IAC to treat AF. Methods and results Persistent AF was simulated in 12 patient-specific geometries, incorporating electrophysiological heterogeneity and fibres, with IAC at Bachmann’s bundle, the coronary sinus, and fossa ovalis. Simulations were performed to test the effect of left atrial (LA)-to-RA frequency gradient and fibrotic remodelling on IAC ablation efficacy. During AF, we simulated ablation of one, two, or all three IAC, with or without pulmonary vein isolation and determined if this altered or terminated the arrhythmia. For models without structural remodelling, ablating all IAC terminated RA arrhythmia in 83% of cases. Models with the LA-to-RA frequency gradient removed had an increased success rate (100% success). Ablation of IACs is less effective in cases with fibrotic remodelling (interstitial fibrosis 50% success rate; combination remodelling 67%). Mean number of phase singularities in the RA was higher pre-ablation for IAC failure (success 0.6 ± 0.8 vs. failure 3.2 ± 2.5, P < 0.001). Conclusion This simulation study predicts that IAC ablation is effective in returning the RA to SR for many cases. Patient-specific modelling approaches have the potential to stratify patients prior to ablation by predicting if drivers are located in the LA or RA. We present a platform for predicting efficacy and informing patient selection for speculative treatments.
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Affiliation(s)
- Caroline H Roney
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Steven E Williams
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Hubert Cochet
- LIRYC Electrophysiology and Heart Modeling Institute, Bordeaux Fondation, Avenue du Haut-Lévèque, Pessac, France
| | - Rahul K Mukherjee
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Louisa O'Neill
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Iain Sim
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - John Whitaker
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Orod Razeghi
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | | | - Edward J Vigmond
- LIRYC Electrophysiology and Heart Modeling Institute, Bordeaux Fondation, Avenue du Haut-Lévèque, Pessac, France.,IMB, Univ. Bordeaux, Talence, France
| | - Mark O'Neill
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
| | - Steven A Niederer
- School of Biomedical Engineering & Imaging Sciences, King's College London, St. Thomas' Hospital, Westminster Bridge Road, UK
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Mukherjee RK, Costa CM, Neji R, Harrison JL, Sim I, Williams SE, Whitaker J, Chubb H, O'Neill L, Schneider R, Lloyd T, Pohl T, Roujol S, Niederer SA, Razavi R, O'Neill MD. Evaluation of a real-time magnetic resonance imaging-guided electrophysiology system for structural and electrophysiological ventricular tachycardia substrate assessment. Europace 2019; 21:1432-1441. [PMID: 31219547 PMCID: PMC6735875 DOI: 10.1093/europace/euz165] [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: 01/17/2019] [Accepted: 05/22/2019] [Indexed: 11/21/2022] Open
Abstract
Aims Potential advantages of real-time magnetic resonance imaging (MRI)-guided electrophysiology (MR-EP) include contemporaneous three-dimensional substrate assessment at the time of intervention, improved procedural guidance, and ablation lesion assessment. We evaluated a novel real-time MR-EP system to perform endocardial voltage mapping and assessment of delayed conduction in a porcine ischaemia–reperfusion model. Methods and results Sites of low voltage and slow conduction identified using the system were registered and compared to regions of late gadolinium enhancement (LGE) on MRI. The Sorensen–Dice similarity coefficient (DSC) between LGE scar maps and voltage maps was computed on a nodal basis. A total of 445 electrograms were recorded in sinus rhythm (range: 30–186) using the MR-EP system including 138 electrograms from LGE regions. Pacing captured at 103 sites; 47 (45.6%) sites had a stimulus-to-QRS (S-QRS) delay of ≥40 ms. Using conventional (0.5–1.5 mV) bipolar voltage thresholds, the sensitivity and specificity of voltage mapping using the MR-EP system to identify MR-derived LGE was 57% and 96%, respectively. Voltage mapping had a better predictive ability in detecting LGE compared to S-QRS measurements using this system (area under curve: 0.907 vs. 0.840). Using an electrical threshold of 1.5 mV to define abnormal myocardium, the total DSC, scar DSC, and normal myocardium DSC between voltage maps and LGE scar maps was 79.0 ± 6.0%, 35.0 ± 10.1%, and 90.4 ± 8.6%, respectively. Conclusion Low-voltage zones and regions of delayed conduction determined using a real-time MR-EP system are moderately associated with LGE areas identified on MRI.
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Affiliation(s)
- Rahul K Mukherjee
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Caroline Mendonca Costa
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Radhouene Neji
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK.,Siemens Healthcare, Sir William Siemens Square, Frimley, Camberley, UK
| | - James L Harrison
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK.,Department of Cardiology, King's College Hospital NHS Foundation Trust, London, UK
| | - Iain Sim
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Henry Chubb
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Louisa O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | | | - Tom Lloyd
- Imricor Medical Systems, 400 Gateway Blvd, MN, USA
| | | | - Sébastien Roujol
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Steven A Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK
| | - Mark D O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor, North Wing, St Thomas' Hospital, London, UK.,Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
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47
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Chubb H, Karim R, Mukherjee R, Williams SE, Whitaker J, Harrison J, Niederer SA, Staab W, Gill J, Schaeffter T, Wright M, O'Neill M, Razavi R. A comprehensive multi‐index cardiac magnetic resonance‐guided assessment of atrial fibrillation substrate prior to ablation: Prediction of long‐term outcomes. J Cardiovasc Electrophysiol 2019; 30:1894-1903. [DOI: 10.1111/jce.14111] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 07/17/2019] [Accepted: 08/05/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Henry Chubb
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Rashed Karim
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Rahul Mukherjee
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Steven E. Williams
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
- Department of CardiologySt Thomas’ HospitalLondon UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - James Harrison
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
- Department of CardiologySt Thomas’ HospitalLondon UK
| | - Steven A. Niederer
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
- Department of CardiologySt Thomas’ HospitalLondon UK
| | - Wieland Staab
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Jaspal Gill
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Tobias Schaeffter
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
| | - Matthew Wright
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
- Department of CardiologySt Thomas’ HospitalLondon UK
| | - Mark O'Neill
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
- Department of CardiologySt Thomas’ HospitalLondon UK
| | - Reza Razavi
- Division of Imaging Sciences and Biomedical EngineeringKing's College LondonLondon UK
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Kennedy MB, Williams SE, Haq I, Okorie M. UK medical students' perspectives on practical prescribing teaching and learning provisions: a cross-sectional survey. Eur J Clin Pharmacol 2019; 75:1451-1458. [PMID: 31317216 DOI: 10.1007/s00228-019-02718-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 07/11/2019] [Indexed: 11/28/2022]
Abstract
PURPOSE To determine medical students' perspectives on the provision for the teaching and learning of processes that lead to and include the writing of a clear, safe and legal prescription (practical prescribing) in UK medical schools. METHODS We designed a cross-sectional survey of UK medical students in years three, four and five. Students were asked about their experiences and views of practical prescribing teaching and learning they had encountered on their medical course. RESULTS A total of 1023 medical students responded (7% response rate), from 25 UK medical schools: 22%, 37% and 41% in the third, fourth and final years, respectively. Teaching of practical prescribing was widespread, with 94.3% of final year (n = 396, 95% confidence interval [CI] = 92-97%), 86.8% of fourth year (n = 328, CI = 83-90%) and 73.8% of third year (n = 166, CI = 67-80%) students reporting they had received it. Availability of this teaching appeared to vary by medical school. Self-directed learning was the most frequently reported mode of delivery (90.9%, n = 809). Validated pre-prescribing and simulation were perceived by students in each year group as the most effective methods. Clinical pharmacologists, clinical pharmacists and junior doctors were perceived by the students as being the most effective professional groups at teaching practical prescribing. CONCLUSIONS UK medical students reported a variety of methods utilised in the teaching and learning of practical prescribing. However, methods they perceived to be very effective (simulation and pre-prescribing) do not appear to be widely available or are only reserved for the final year of study. Combining such methods with involvement of professional groups perceived to be most effective should be explored.
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Affiliation(s)
- M B Kennedy
- Department of Medical Education, Brighton and Sussex Medical School, Brighton, UK
| | - S E Williams
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK
| | - I Haq
- Sydney Medical Programme, University of Sydney, Sydney, New South Wales, Australia
| | - M Okorie
- Department of Medical Education, Brighton and Sussex Medical School, Brighton, UK.
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49
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Williams SE, Linton NWF, Harrison J, Chubb H, Whitaker J, Gill J, Rinaldi CA, Razavi R, Niederer S, Wright M, O'Neill M. Intra-Atrial Conduction Delay Revealed by Multisite Incremental Atrial Pacing is an Independent Marker of Remodeling in Human Atrial Fibrillation. JACC Clin Electrophysiol 2019; 3:1006-1017. [PMID: 28966986 PMCID: PMC5612260 DOI: 10.1016/j.jacep.2017.02.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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] [Indexed: 11/30/2022]
Abstract
Objectives This study sought to characterize direction-dependent and coupling interval–dependent changes in left atrial conduction and electrogram morphology in uniformly classified patients with paroxysmal atrial fibrillation (AF) and normal bipolar voltage mapping. Background Although AF classifications are based on arrhythmia duration, the clinical course, and treatment response vary between patients within these groups. Electrophysiological mechanisms responsible for this variability are incompletely described. Methods Intracardiac contact mapping during incremental atrial pacing was used to characterize atrial conduction, activation dispersion, and electrogram morphology in 15 consecutive paroxysmal AF patients undergoing first-time pulmonary vein isolation. Outcome measures were vulnerability to AF induction at electrophysiology study and 2-year follow-up for arrhythmia recurrence. Results Conduction delay showed a bimodal distribution, occurring at either long (high right atrium pacing: 326 ± 13 ms; coronary sinus pacing: 319 ± 16 ms) or short (high right atrium pacing: 275 ± 11 ms; coronary sinus pacing: 271 ± 11 ms) extrastimulus coupling intervals. Arrhythmia recurrence was found only in patients with conduction delay at long extrastimulus coupling intervals, and patients with inducible AF were characterized by increased activation dispersion (activation dispersion time: 168 ± 29 ms vs. 136 ± 11 ms). Electrogram voltage and duration varied throughout the left atrium, between patients, and with pacing site but were not correlated with AF vulnerability or arrhythmia recurrence. Conclusions Within the single clinical entity of paroxysmal AF, incremental atrial pacing identified a spectrum of activation patterns correlating with AF vulnerability and arrhythmia recurrence. In contrast, electrogram morphology (characterized by electrogram voltage and duration) was highly variable and not associated with AF vulnerability or recurrence. An improved understanding of the electrical phenotype in AF could lead to improved mechanistic classifications.
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Key Words
- ADT, activation dispersion time
- AF substrate
- AF, atrial fibrillation
- CS, coronary sinus
- ED, electrogram duration
- ERP, effective refractory period
- EV, electrogram voltage
- HRA, high right atrium
- LA, left atrial
- PAF, paroxysmal AF
- S1S2block, the shortest S1S2 coupling interval that conducts from pacing site to left atrium
- S1S2delay, the shortest S1S2 coupling interval conducting without decrement to the left atrium
- atrial fibrillation
- atrial remodeling
- electrophysiology testing
- ΔED, rate dependence of electrogram duration
- ΔEV, rate dependence of electrogram voltage
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Affiliation(s)
- Steven E Williams
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Nick W F Linton
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - James Harrison
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Henry Chubb
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Jaswinder Gill
- Cardiovascular Division, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Christopher A Rinaldi
- Cardiovascular Division, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Reza Razavi
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Steven Niederer
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Matthew Wright
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
| | - Mark O'Neill
- Division of Imaging Sciences and Biomedical Imaging, King's College London, London, United Kingdom
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50
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Mukherjee RK, Whitaker J, Williams SE, Razavi R, O'Neill MD. Magnetic resonance imaging guidance for the optimization of ventricular tachycardia ablation. Europace 2019; 20:1721-1732. [PMID: 29584897 PMCID: PMC6212773 DOI: 10.1093/europace/euy040] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [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: 11/06/2017] [Accepted: 02/19/2018] [Indexed: 01/02/2023] Open
Abstract
Catheter ablation has an important role in the management of patients with ventricular tachycardia (VT) but is limited by modest long-term success rates. Magnetic resonance imaging (MRI) can provide valuable anatomic and functional information as well as potentially improve identification of target sites for ablation. A major limitation of current MRI protocols is the spatial resolution required to identify the areas of tissue responsible for VT but recent developments have led to new strategies which may improve substrate assessment. Potential ways in which detailed information gained from MRI may be utilized during electrophysiology procedures include image integration or performing a procedure under real-time MRI guidance. Image integration allows pre-procedural magnetic resonance (MR) images to be registered with electroanatomical maps to help guide VT ablation and has shown promise in preliminary studies. However, multiple errors can arise during this process due to the registration technique used, changes in ventricular geometry between the time of MRI and the ablation procedure, respiratory and cardiac motion. As isthmus sites may only be a few millimetres wide, reducing these errors may be critical to improve outcomes in VT ablation. Real-time MR-guided intervention has emerged as an alternative solution to address the limitations of pre-acquired imaging to guide ablation. There is now a growing body of literature describing the feasibility, techniques, and potential applications of real-time MR-guided electrophysiology. We review whether real-time MR-guided intervention could be applied in the setting of VT ablation and the potential challenges that need to be overcome.
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Affiliation(s)
- Rahul K Mukherjee
- School of Biomedical Engineering and Imaging Sciences, 4th Floor, North Wing, St Thomas' Hospital, King's College London, London, UK
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, 4th Floor, North Wing, St Thomas' Hospital, King's College London, London, UK
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, 4th Floor, North Wing, St Thomas' Hospital, King's College London, London, UK.,Department of Cardiology, Guy's and St Thomas' Hospital NHS Foundation Trust, London, UK
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, 4th Floor, North Wing, St Thomas' Hospital, King's College London, London, UK
| | - Mark D O'Neill
- School of Biomedical Engineering and Imaging Sciences, 4th Floor, North Wing, St Thomas' Hospital, King's College London, London, UK.,Department of Cardiology, Guy's and St Thomas' Hospital NHS Foundation Trust, London, UK
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