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Aranyó J, Martínez-Falguera D, Teis A, Fadeuilhe E, Rodríguez-Leor O, Bazan V, Sarrias A, Tebe C, Villuendas R, Delgado V, Bayés-Genís A, Gálvez-Montón C, Bisbal F. Tissue Characteristics Underlying Endocardial Local Impedance Subtypes in Chronic myocardial Infarction. Heart Rhythm 2025:S1547-5271(25)02440-3. [PMID: 40383178 DOI: 10.1016/j.hrthm.2025.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2025] [Revised: 05/01/2025] [Accepted: 05/12/2025] [Indexed: 05/20/2025]
Abstract
BACKGROUND Local impedance (LI) mapping is feasible and provides additional tissue characterization of the ventricular tachycardia substrate. Data on tissue composition underlying the LI spectrum are lacking. OBJECTIVE To describe the tissue composition underlying different LI subtypes in a chronic myocardial infarction (MI) swine model. METHODS One month after non-reperfused anterior MI, eigtheen Landrace Large White pigs underwent delayed-enhancement cardiac magnetic resonance (DE-CMR) and endocardial left ventricular (LV) LI mapping. DE-CMR images were post-processed off-line to obtain LV wall thickness, scar subtypes, and border-zone (BZ) corridors, and were co-registered with LI maps. Tissue samples were obtained from abnormal LI sites. RESULTS Low LI zones exhibited more pronounced wall thinning compared to intermediate LI tissue (2.8±0.7 vs 3.8 ± 0.9 mm; P < 0.001) and correlated with DE-CMR dense endocardial scarring (91.4%) and with epicardial scarring (75% dense and 24% BZ tissue). Intermediate LI tissue exhibited predominantly subendocardial scarring, with more heterogeneous distribution (45% dense, 47% BZ, and 8% healthy tissue) and less epicardial involvement (73% healthy tissue). Most DE-CMR BZ corridors (75.6%) co-localized with intermediate LI tissue. Histologically, tissue from intermediate LI zones displayed less collagen I (P = 0.008), collagen III (P = 0.053), and collagen volume fraction (P = 0.021), and greater vascular density (P = 0.075), compared to low LI zones. CONCLUSIONS Areas of low LI had higher proportion of dense, transmural scar and wall thinning compared to intermediate LI areas. DE-CMR BZ corridors colocalized with intermediate LI in most cases. LI subtypes showed distinctive histological composition.
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Affiliation(s)
- Júlia Aranyó
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; Department of Medicine, Autonomous University of Barcelona (UAB)
| | - Daina Martínez-Falguera
- ICREC Research Program, Germans Trias I Pujol Research Institute (IGTP), Badalona, Barcelona, Spain; Faculty of Medicine, University of Barcelona (UB), Spain
| | - Albert Teis
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; CIBER Cardiovascular, Instituto de Salud Carlos III, Madrid, Spain
| | - Edgar Fadeuilhe
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain
| | - Oriol Rodríguez-Leor
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain
| | - Víctor Bazan
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain
| | - Axel Sarrias
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain
| | - Cristian Tebe
- Biostatistics Support and Research Unit, Germans Trias i Pujol Research Institute and Hospital (IGTP), Badalona, Barcelona, Spain
| | - Roger Villuendas
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain
| | - Victoria Delgado
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; Centre of Comparative Medicine and Bioimaging, Badalona, Spain
| | - Antoni Bayés-Genís
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; CIBER Cardiovascular, Instituto de Salud Carlos III, Madrid, Spain; Department of Medicine, Can Ruti Campus, Autonomous University of Barcelona, Spain
| | - Carolina Gálvez-Montón
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; ICREC Research Program, Germans Trias I Pujol Research Institute (IGTP), Badalona, Barcelona, Spain; CIBER Cardiovascular, Instituto de Salud Carlos III, Madrid, Spain.
| | - Felipe Bisbal
- Heart Institute (iCOR), Germans Trias i Pujol University Hospital, Badalona, Barcelona, Spain; CIBER Cardiovascular, Instituto de Salud Carlos III, Madrid, Spain.
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Ciaccio EJ, Hsia HH, Robinson D, Cedilnik N, Zeldin L, Wan EY, Biviano AB, Yarmohammadi H, Saluja DS. Uniform slow conduction during sinus rhythm and low voltage/low voltage gradient ΔV/V characterize the VT isthmus location. Heart Rhythm 2024:S1547-5271(24)03635-X. [PMID: 39615817 DOI: 10.1016/j.hrthm.2024.11.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2024] [Revised: 11/12/2024] [Accepted: 11/25/2024] [Indexed: 12/15/2024]
Abstract
BACKGROUND Reentrant ventricular tachycardia (VT) properties require further elucidation. OBJECTIVE To understand circuit mechanisms and improve ablation targeting. METHODS In postinfarction VT patients undergoing electrophysiology study and catheter ablation, high-density endocardial electrogram contact mapping data was acquired during sinus rhythm (n = 6) and during VT (n = 12) and annotated by the system. Bipolar endocardial VT voltage was used to compute the voltage gradient, ΔV/V, at isthmus midline and at the lateral boundaries. Voltage was additionally represented as a depth as well as a color change, to better visualize level. Linear regression analysis was implemented to quantitate the sinus rhythm activation gradient along the isthmus long-axis midline, and along 3 other spokes originating from a last activation point. RESULTS The mean voltage along the isthmus long-axis was 0.234 ± 0.137 mV, vs 0.383 ± 0.290 mV aside boundaries (P < .001). The gradient ΔV/V along the isthmus long-axis was 0.425 ± 0.324, vs 0.823 ± 0.550 at boundaries (P < .001). Sinus rhythm activation was uniform (mean r2 = 0.93 ± 0.05) and slow (∇ = 0.16 ± 0.03 mm/msec) along the spoke coinciding with isthmus long-axis midline, vs less uniform (mean r2 = 0.32 ± 0.25) and rapid (∇ = 0.73 ± 0.62 mm/msec) along the other spokes (P < .001 and P = .003, respectively). Plotting r2 vs ∇, parameters of isthmus vs nonisthmus spokes were clearly separable. CONCLUSION A low-voltage trench coincides with the VT isthmus, vs abrupt voltage increase at the lateral boundaries, which may contravene prior definitions of conducting channels. Sinus rhythm uniform slow conduction occurs at the VT isthmus location, preventing circuit disruption while enabling the formation of an excitable gap to perpetuate reentry.
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Affiliation(s)
- Edward J Ciaccio
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York.
| | - Henry H Hsia
- Cardiac Electrophysiology and Arrhythmia Service, University of California San Francisco, San Francisco, California
| | - David Robinson
- inHEART Medical, Hoôpital Xavier Arnozan, Pessac, France
| | | | - Lawrence Zeldin
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
| | - Elaine Y Wan
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
| | - Angelo B Biviano
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
| | - Hirad Yarmohammadi
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
| | - Deepak S Saluja
- Department of Medicine, Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
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Kovacs B, Ghannam M, Liang J, Deshmukh A, Attili A, Cochet H, Latchamsetty R, Jongnarangsin K, Morady F, Bogun F. Value of multimodality imaging for ventricular tachycardia ablation in patients with structural heart disease. Heart Rhythm 2024:S1547-5271(24)03458-1. [PMID: 39447818 DOI: 10.1016/j.hrthm.2024.10.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 10/05/2024] [Accepted: 10/17/2024] [Indexed: 10/26/2024]
Affiliation(s)
- Boldizsar Kovacs
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Michael Ghannam
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Jackson Liang
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Amrish Deshmukh
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Anil Attili
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | | | - Rakesh Latchamsetty
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Krit Jongnarangsin
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Fred Morady
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - Frank Bogun
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan.
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Krahn PRP, Escartin T, Singh SM, Barry J, Larsen M, Guo F, Pop M, Wright GA. MRI Accurately Visualizes RF Ablation Delivery Targeted to MRI-Defined Arrhythmia Substrates in the Left Ventricle. IEEE Trans Biomed Eng 2024; 71:2749-2758. [PMID: 38648149 DOI: 10.1109/tbme.2024.3392333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
OBJECTIVE Investigate the capacity of MRI to evaluate efficacy of radiofrequency (RF) ablations delivered to MRI-defined arrhythmogenic substrates. METHODS Baseline MRI was performed at 3 T including 3D LGE in a swine model of chronic myocardial infarct (N = 8). MRI-derived maps of scar and heterogeneous tissue channels (HTCs) were generated using ADAS 3D. Animals underwent electroanatomic mapping and ablation of the left ventricle in CARTO3, guided by MRI-derived scar maps. Post-ablation MRI (in vivo at 3 T in 5/8 animals; ex vivo at 1.5 T in 3/8) included 3D native T1-weighted IR-SPGR (TI = 700-800 ms) to visualize RF lesions. T1-derived RF lesions were compared against excised tissue. The locations of T1-derived RF lesions were compared against CARTO ablation tags, and segment-wise sensitivity and specificity of lesion detection were calculated within the AHA 17-segment model. RESULTS RF lesions were clearly visualized in HTCs, scar, and myocardium. Ablation patterns delivered in CARTO matched T1-derived RF lesion patterns with high sensitivity (88.9%) and specificity (94.7%), and were closely matched in registered MR-EP data sets, with a displacement of 5.4 ±3.8 mm (N = 152 ablation tags). CONCLUSION Integrating MRI into ablative procedures for RF lesion assessment is feasible. Patterns of RF lesions created using a standard 3D EAM system are accurately reflected by MRI visualization in healthy myocardium, scar, and HTCs comprising the MRI-defined arrhythmia substrate. SIGNIFICANCE MRI visualization of RF lesions can provide near-immediate ( 24 h) assessment of ablation, potentially indicating whether critical MRI-defined ventricular tachycardia substrates have been adequately ablated.
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Tampakis K, Pastromas S, Sykiotis A, Kampanarou S, Kourgiannidis G, Pyrpiri C, Bousoula M, Rozakis D, Andrikopoulos G. Real-time cardiovascular magnetic resonance-guided radiofrequency ablation: A comprehensive review. World J Cardiol 2023; 15:415-426. [PMID: 37900261 PMCID: PMC10600785 DOI: 10.4330/wjc.v15.i9.415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/10/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023] Open
Abstract
Cardiac magnetic resonance (CMR) imaging could enable major advantages when guiding in real-time cardiac electrophysiology procedures offering high-resolution anatomy, arrhythmia substrate, and ablation lesion visualization in the absence of ionizing radiation. Over the last decade, technologies and platforms for performing electrophysiology procedures in a CMR environment have been developed. However, performing procedures outside the conventional fluoroscopic laboratory posed technical, practical and safety concerns. The development of magnetic resonance imaging compatible ablation systems, the recording of high-quality electrograms despite significant electromagnetic interference and reliable methods for catheter visualization and lesion assessment are the main limiting factors. The first human reports, in order to establish a procedural workflow, have rationally focused on the relatively simple typical atrial flutter ablation and have shown that CMR-guided cavotricuspid isthmus ablation represents a valid alternative to conventional ablation. Potential expansion to other more complex arrhythmias, especially ventricular tachycardia and atrial fibrillation, would be of essential impact, taking into consideration the widespread use of substrate-based strategies. Importantly, all limitations need to be solved before application of CMR-guided ablation in a broad clinical setting.
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Affiliation(s)
- Konstantinos Tampakis
- Department of Pacing & Electrophysiology, Henry Dunant Hospital Center, Athens 11526, Greece.
| | - Sokratis Pastromas
- Department of Pacing & Electrophysiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | - Alexandros Sykiotis
- Department of Pacing & Electrophysiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | | | - Georgios Kourgiannidis
- Department of Pacing & Electrophysiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | - Chrysa Pyrpiri
- Department of Radiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | - Maria Bousoula
- Department of Anesthesiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | - Dimitrios Rozakis
- Department of Anesthesiology, Henry Dunant Hospital Center, Athens 11526, Greece
| | - George Andrikopoulos
- Department of Pacing & Electrophysiology, Henry Dunant Hospital Center, Athens 11526, Greece
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Maher TR, Freedman BL, Locke AH, Tracey M, Waks JW, Litmanovich D, d'Avila A. Correlation Between Functional Substrate Mapping and Cardiac Computed Tomography-Derived Wall Thinning for Ventricular Tachycardia Ablation. JACC Clin Electrophysiol 2023; 9:1878-1889. [PMID: 37480860 DOI: 10.1016/j.jacep.2023.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 05/08/2023] [Accepted: 05/12/2023] [Indexed: 07/24/2023]
Abstract
BACKGROUND Functional substrate mapping during baseline rhythm can identify arrhythmogenic tissue during ventricular tachycardia (VT) ablation. Wall thinning and wall thickness channels (WTCs) derived from computed tomography angiography have been shown to correlate with low voltage and VT isthmuses. The correlation between functional substrate mapping, wall thinning, and WTCs in patients with infarct- or non-infarct-related cardiomyopathies (ICM and NICM, respectively) has not been previously described. OBJECTIVES The purpose of this study was to correlate cardiac CTA-derived myocardial wall thinning with functional VT substrate mapping using isochronal late activation mapping. METHODS In 34 patients with ICM or NICM undergoing VT ablation who had a preprocedure computed tomography angiography, myocardial wall thinning was segmented in layers of 1 to 5 mm. Areas of wall thinning and WTCs were then spatially correlated with deceleration zones (DZs) from registered left ventricular endocardial isochronal late activation maps. RESULTS In 21 ICM patients and 13 NICM patients, ICM patients had greater surfaces areas of wall thinning (P < 0.001). In ICM patients, 94.1% of primary DZs were located on areas of wall thinning, compared to 20% of DZs in NICM patients overall but 50% if there was any wall thinning present. Fifty-nine percent of DZs in ICM patients and 56% of DZs in NICM patients were located near WTCs. The positive predictive value for WTC in localizing DZs was 22.5% and 37.8% in ICM and NICM patients, respectively. CONCLUSIONS Wall thinning is highly sensitive for functional substrate in ICM patients. WTCs had modest sensitivity for functional substrate but low positive predictive value for identifying DZs in ICM and NICM patients. These findings suggest that wall thinning may facilitate more efficient mapping in ICM patients, but WTCs are insufficient to localize wavefront discontinuities.
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Affiliation(s)
- Timothy R Maher
- Harvard-Thorndike Electrophysiology Institute and Arrhythmia Service, Division of Cardiovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Benjamin L Freedman
- Harvard-Thorndike Electrophysiology Institute and Arrhythmia Service, Division of Cardiovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Andrew H Locke
- Harvard-Thorndike Electrophysiology Institute and Arrhythmia Service, Division of Cardiovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Jonathan W Waks
- Harvard-Thorndike Electrophysiology Institute and Arrhythmia Service, Division of Cardiovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Diana Litmanovich
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Andre d'Avila
- Harvard-Thorndike Electrophysiology Institute and Arrhythmia Service, Division of Cardiovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
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Tung R, Tamarappoo B, Morris MF. Scar, Fat, and Fibrosis: Rethinking Re-Entry. JACC Clin Electrophysiol 2023; 9:1246-1247. [PMID: 37558286 DOI: 10.1016/j.jacep.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 06/29/2023] [Accepted: 06/29/2023] [Indexed: 08/11/2023]
Affiliation(s)
- Roderick Tung
- Division of Cardiology, Banner University Medical Center, The University of Arizona College of Medicine, Phoenix, Arizona, USA.
| | - Balaji Tamarappoo
- Division of Cardiology, Banner University Medical Center, The University of Arizona College of Medicine, Phoenix, Arizona, USA
| | - Michael F Morris
- Division of Cardiology, Banner University Medical Center, The University of Arizona College of Medicine, Phoenix, Arizona, USA
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Dokuchaev A, Chumarnaya T, Bazhutina A, Khamzin S, Lebedeva V, Lyubimtseva T, Zubarev S, Lebedev D, Solovyova O. Combination of personalized computational modeling and machine learning for optimization of left ventricular pacing site in cardiac resynchronization therapy. Front Physiol 2023; 14:1162520. [PMID: 37497440 PMCID: PMC10367108 DOI: 10.3389/fphys.2023.1162520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023] Open
Abstract
Introduction: The 30-50% non-response rate to cardiac resynchronization therapy (CRT) calls for improved patient selection and optimized pacing lead placement. The study aimed to develop a novel technique using patient-specific cardiac models and machine learning (ML) to predict an optimal left ventricular (LV) pacing site (ML-PS) that maximizes the likelihood of LV ejection fraction (LVEF) improvement in a given CRT candidate. To validate the approach, we evaluated whether the distance DPS between the clinical LV pacing site (ref-PS) and ML-PS is associated with improved response rate and magnitude. Materials and methods: We reviewed retrospective data for 57 CRT recipients. A positive response was defined as a more than 10% LVEF improvement. Personalized models of ventricular activation and ECG were created from MRI and CT images. The characteristics of ventricular activation during intrinsic rhythm and biventricular (BiV) pacing with ref-PS were derived from the models and used in combination with clinical data to train supervised ML classifiers. The best logistic regression model classified CRT responders with a high accuracy of 0.77 (ROC AUC = 0.84). The LR classifier, model simulations and Bayesian optimization with Gaussian process regression were combined to identify an optimal ML-PS that maximizes the ML-score of CRT response over the LV surface in each patient. Results: The optimal ML-PS improved the ML-score by 17 ± 14% over the ref-PS. Twenty percent of the non-responders were reclassified as positive at ML-PS. Selection of positive patients with a max ML-score >0.5 demonstrated an improved clinical response rate. The distance DPS was shorter in the responders. The max ML-score and DPS were found to be strong predictors of CRT response (ROC AUC = 0.85). In the group with max ML-score > 0.5 and DPS< 30 mm, the response rate was 83% compared to 14% in the rest of the cohort. LVEF improvement in this group was higher than in the other patients (16 ± 8% vs. 7 ± 8%). Conclusion: A new technique combining clinical data, personalized heart modelling and supervised ML demonstrates the potential for use in clinical practice to assist in optimizing patient selection and predicting optimal LV pacing lead position in HF candidates for CRT.
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Affiliation(s)
- Arsenii Dokuchaev
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| | - Tatiana Chumarnaya
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Laboratory of Mathematical Modeling in Physiology and Medicine Based on Supercomputers, Ural Federal University, Ekaterinburg, Russia
| | - Anastasia Bazhutina
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Laboratory of Mathematical Modeling in Physiology and Medicine Based on Supercomputers, Ural Federal University, Ekaterinburg, Russia
| | - Svyatoslav Khamzin
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| | | | - Tamara Lyubimtseva
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Stepan Zubarev
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Dmitry Lebedev
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Olga Solovyova
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
- Laboratory of Mathematical Modeling in Physiology and Medicine Based on Supercomputers, Ural Federal University, Ekaterinburg, Russia
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Amoni M, Vermoortele D, Ekhteraei-Tousi S, Doñate Puertas R, Gilbert G, Youness M, Thienpont B, Willems R, Roderick HL, Claus P, Sipido KR. Heterogeneity of Repolarization and Cell-Cell Variability of Cardiomyocyte Remodeling Within the Myocardial Infarction Border Zone Contribute to Arrhythmia Susceptibility. Circ Arrhythm Electrophysiol 2023; 16:e011677. [PMID: 37128895 PMCID: PMC10187631 DOI: 10.1161/circep.122.011677] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 04/07/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND After myocardial infarction, the infarct border zone (BZ) is the dominant source of life-threatening arrhythmias, where fibrosis and abnormal repolarization create a substrate for reentry. We examined whether repolarization abnormalities are heterogeneous within the BZ in vivo and could be related to heterogeneous cardiomyocyte remodeling. METHODS Myocardial infarction was induced in domestic pigs by 120-minute ischemia followed by reperfusion. After 1 month, remodeling was assessed by magnetic resonance imaging, and electroanatomical mapping was performed to determine the spatial distribution of activation-recovery intervals. Cardiomyocytes were isolated and tissue samples collected from the BZ and remote regions. Optical recording allowed assessment of action potential duration (di-8-ANEPPS, stimulation at 1 Hz, 37 °C) of large cardiomyocyte populations while gene expression in cardiomyocytes was determined by single nuclear RNA sequencing. RESULTS In vivo, activation-recovery intervals in the BZ tended to be longer than in remote with increased spatial heterogeneity evidenced by a greater local SD (3.5±1.3 ms versus remote: 2.0±0.5 ms, P=0.036, npigs=5). Increased activation-recovery interval heterogeneity correlated with enhanced arrhythmia susceptibility. Cellular population studies (ncells=635-862 cells per region) demonstrated greater heterogeneity of action potential duration in the BZ (SD, 105.9±17.0 ms versus remote: 73.9±8.6 ms; P=0.001; npigs=6), which correlated with heterogeneity of activation-recovery interval in vivo. Cell-cell gene expression heterogeneity in the BZ was evidenced by increased Euclidean distances between nuclei of the BZ (12.1 [9.2-15.0] versus 10.6 [7.5-11.6] in remote; P<0.0001). Differentially expressed genes characterizing BZ cardiomyocyte remodeling included hypertrophy-related and ion channel-related genes with high cell-cell variability of expression. These gene expression changes were driven by stress-responsive TFs (transcription factors). In addition, heterogeneity of left ventricular wall thickness was greater in the BZ than in remote. CONCLUSIONS Heterogeneous cardiomyocyte remodeling in the BZ is driven by uniquely altered gene expression, related to heterogeneity in the local microenvironment, and translates to heterogeneous repolarization and arrhythmia vulnerability in vivo.
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Affiliation(s)
- Matthew Amoni
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
- Division of Cardiology, University Hospitals, Leuven, Belgium (M.A., R.W.)
| | - Dylan Vermoortele
- Imaging and Cardiovascular Dynamics, Department of Cardiovascular Sciences (D.V., P.C.), KU Leuven, Belgium
| | - Samaneh Ekhteraei-Tousi
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
| | - Rosa Doñate Puertas
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
| | - Guillaume Gilbert
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
| | - Mohamad Youness
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
| | - Bernard Thienpont
- Laboratory for Functional Epigenetics, Department of Human Genetics (B.T.), KU Leuven, Belgium
| | - Rik Willems
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
- Division of Cardiology, University Hospitals, Leuven, Belgium (M.A., R.W.)
| | - H. Llewelyn Roderick
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
| | - Piet Claus
- Imaging and Cardiovascular Dynamics, Department of Cardiovascular Sciences (D.V., P.C.), KU Leuven, Belgium
| | - Karin R. Sipido
- Department of Cardiovascular Sciences, Experimental Cardiology (M.A., S.E.-T., R.D.P., G.G., M.Y., R.W., H.L.R., K.R.S.), KU Leuven, Belgium
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Automatic development of 3D anatomical models of border zone and core scar regions in the left ventricle. Comput Med Imaging Graph 2023; 103:102152. [PMID: 36525769 DOI: 10.1016/j.compmedimag.2022.102152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/17/2022] [Accepted: 11/27/2022] [Indexed: 12/03/2022]
Abstract
Patients with myocardial infarction are at elevated risk of sudden cardiac death, and scar tissue arising from infarction is known to play a role. The accurate identification of scars therefore is crucial for risk assessment, quantification and guiding interventions. Typically, core scars and grey peripheral zones are identified by radiologists and clinicians based on cardiac late gadolinium enhancement magnetic resonance images (LGE-MRI). Scar regions from LGE-MRI vary in size, shape, heterogeneity, artifacts, and image resolution. Thus, manual segmentation is time consuming, and influenced by the observer's experience (bias effect). We propose a fully automatic framework that develops 3D anatomical models of the left ventricle with border zone and core scar regions that are free from bias effect. Our myocardium (SOCRATIS), border scar and core scar (BZ-SOCRATIS) segmentation pipelines were evaluated using internal and external validation datasets. The automatic myocardium segmentation framework performed a Dice score of 81.9% and 70.0% in the internal and external validation dataset. The automatic scar segmentation pipeline achieved a Dice score of 60.9% for the core scar segmentation and 43.7% for the border zone scar segmentation in the internal dataset and in the external dataset a Dice score of 44.2% for the core scar segmentation and 54.8% for the border scar segmentation respectively. To the best of our knowledge, this is the first study outlining a fully automatic framework to develop 3D anatomical models of the left ventricle with border zone and core scar regions. Our method exhibits high performance without the need for training or tuning in an unseen cohort (unsupervised).
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Ono K, Iwasaki Y, Akao M, Ikeda T, Ishii K, Inden Y, Kusano K, Kobayashi Y, Koretsune Y, Sasano T, Sumitomo N, Takahashi N, Niwano S, Hagiwara N, Hisatome I, Furukawa T, Honjo H, Maruyama T, Murakawa Y, Yasaka M, Watanabe E, Aiba T, Amino M, Itoh H, Ogawa H, Okumura Y, Aoki‐Kamiya C, Kishihara J, Kodani E, Komatsu T, Sakamoto Y, Satomi K, Shiga T, Shinohara T, Suzuki A, Suzuki S, Sekiguchi Y, Nagase S, Hayami N, Harada M, Fujino T, Makiyama T, Maruyama M, Miake J, Muraji S, Murata H, Morita N, Yokoshiki H, Yoshioka K, Yodogawa K, Inoue H, Okumura K, Kimura T, Tsutsui H, Shimizu W, the Japanese Circulation Society and, Japanese Heart Rhythm Society Joint Working Group. JCS/JHRS 2020 Guideline on Pharmacotherapy of Cardiac Arrhythmias. J Arrhythm 2022; 38:833-973. [PMID: 35283400 PMCID: PMC9745564 DOI: 10.1002/joa3.12714] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Ghannam M, Bogun F. Improving Outcomes in Ventricular Tachycardia Ablation Using Imaging to Identify Arrhythmic Substrates. Card Electrophysiol Clin 2022; 14:609-620. [PMID: 36396180 DOI: 10.1016/j.ccep.2022.06.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Ventricular tachycardia (VT) ablation is limited by modest acute and long-term success rates, in part due to the challenges in accurately identifying the arrhythmogenic substrate. The combination of multimodality imaging along with information from electroanatomic mapping allows for a more comprehensive assessment of the arrhythmogenic substrate which facilitates VT ablation, and the use of preprocedural imaging has been shown to improve long-term ablation outcomes. Beyond regional recognition of the arrhythmogenic substrate, advanced imaging techniques can be used to create tailored ablation strategies preprocedurally. This review will focus on how imaging can be used to guide ablation planning and execution with a focus on clinical applications aimed at improving the outcome of VT ablation procedures.
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Affiliation(s)
- Michael Ghannam
- Division of Cardiovascular Medicine, University of Michigan, 1500 E. Medical Center Dr., SPC5853, Ann Arbor, Michigan 48109-5853, USA.
| | - Frank Bogun
- Division of Cardiovascular Medicine, University of Michigan, 1500 E. Medical Center Dr., SPC5853, Ann Arbor, Michigan 48109-5853, USA
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Tore D, Faletti R, Biondo A, Carisio A, Giorgino F, Landolfi I, Rocco K, Salto S, Santonocito A, Ullo F, Anselmino M, Fonio P, Gatti M. Role of Cardiovascular Magnetic Resonance in the Management of Atrial Fibrillation: A Review. J Imaging 2022; 8:300. [PMID: 36354873 PMCID: PMC9696856 DOI: 10.3390/jimaging8110300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 08/30/2023] Open
Abstract
Atrial fibrillation (AF) is the most common arrhythmia, and its prevalence is growing with time. Since the introduction of catheter ablation procedures for the treatment of AF, cardiovascular magnetic resonance (CMR) has had an increasingly important role for the treatment of this pathology both in clinical practice and as a research tool to provide insight into the arrhythmic substrate. The most common applications of CMR for AF catheter ablation are the angiographic study of the pulmonary veins, the sizing of the left atrium (LA), and the evaluation of the left atrial appendage (LAA) for stroke risk assessment. Moreover, CMR may provide useful information about esophageal anatomical relationship to LA to prevent thermal injuries during ablation procedures. The use of late gadolinium enhancement (LGE) imaging allows to evaluate the burden of atrial fibrosis before the ablation procedure and to assess procedural induced scarring. Recently, the possibility to assess atrial function, strain, and the burden of cardiac adipose tissue with CMR has provided more elements for risk stratification and clinical decision making in the setting of catheter ablation planning of AF. The purpose of this review is to provide a comprehensive overview of the potential applications of CMR in the workup of ablation procedures for atrial fibrillation.
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Affiliation(s)
- Davide Tore
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Riccardo Faletti
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Andrea Biondo
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Andrea Carisio
- Department of Radiology, Humanitas Gradenigo Hospital, 10126 Turin, Italy
| | - Fabio Giorgino
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Ilenia Landolfi
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Katia Rocco
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Sara Salto
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Ambra Santonocito
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Federica Ullo
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Matteo Anselmino
- Division of Cardiology, Department of Medical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Paolo Fonio
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
| | - Marco Gatti
- Radiology Unit, Department of Surgical Sciences, University of Turin, Azienda Ospedaliero Universitaria (A.O.U.) Città della Salute e della Scienza di Torino, 10126 Turin, Italy
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14
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Ono K, Iwasaki YK, Akao M, Ikeda T, Ishii K, Inden Y, Kusano K, Kobayashi Y, Koretsune Y, Sasano T, Sumitomo N, Takahashi N, Niwano S, Hagiwara N, Hisatome I, Furukawa T, Honjo H, Maruyama T, Murakawa Y, Yasaka M, Watanabe E, Aiba T, Amino M, Itoh H, Ogawa H, Okumura Y, Aoki-Kamiya C, Kishihara J, Kodani E, Komatsu T, Sakamoto Y, Satomi K, Shiga T, Shinohara T, Suzuki A, Suzuki S, Sekiguchi Y, Nagase S, Hayami N, Harada M, Fujino T, Makiyama T, Maruyama M, Miake J, Muraji S, Murata H, Morita N, Yokoshiki H, Yoshioka K, Yodogawa K, Inoue H, Okumura K, Kimura T, Tsutsui H, Shimizu W. JCS/JHRS 2020 Guideline on Pharmacotherapy of Cardiac Arrhythmias. Circ J 2022; 86:1790-1924. [PMID: 35283400 DOI: 10.1253/circj.cj-20-1212] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2025]
Affiliation(s)
| | - Yu-Ki Iwasaki
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Masaharu Akao
- Department of Cardiovascular Medicine, National Hospital Organization Kyoto Medical Center
| | - Takanori Ikeda
- Department of Cardiovascular Medicine, Toho University Graduate School of Medicine
| | - Kuniaki Ishii
- Department of Pharmacology, Yamagata University Faculty of Medicine
| | - Yasuya Inden
- Department of Cardiology, Nagoya University Graduate School of Medicine
| | - Kengo Kusano
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Yoshinori Kobayashi
- Division of Cardiology, Department of Medicine, Tokai University Hachioji Hospital
| | | | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University
| | - Naokata Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center
| | - Naohiko Takahashi
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Shinichi Niwano
- Department of Cardiovascular Medicine, Kitasato University School of Medicine
| | | | | | - Tetsushi Furukawa
- Department of Bio-information Pharmacology, Medical Research Institute, Tokyo Medical and Dental University
| | - Haruo Honjo
- Research Institute of Environmental Medicine, Nagoya University
| | - Toru Maruyama
- Department of Hematology, Oncology and Cardiovascular Medicine, Kyushu University Hospital
| | - Yuji Murakawa
- The 4th Department of Internal Medicine, Teikyo University School of Medicine, Mizonokuchi Hospital
| | - Masahiro Yasaka
- Department of Cerebrovascular Medicine and Neurology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center
| | - Eiichi Watanabe
- Department of Cardiology, Fujita Health University School of Medicine
| | - Takeshi Aiba
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Mari Amino
- Department of Cardiovascular Medicine, Tokai University School of Medicine
| | - Hideki Itoh
- Division of Patient Safety, Hiroshima University Hospital
| | - Hisashi Ogawa
- Department of Cardiology, National Hospital Organisation Kyoto Medical Center
| | - Yasuo Okumura
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine
| | - Chizuko Aoki-Kamiya
- Department of Obstetrics and Gynecology, National Cerebral and Cardiovascular Center
| | - Jun Kishihara
- Department of Cardiovascular Medicine, Kitasato University School of Medicine
| | - Eitaro Kodani
- Department of Cardiovascular Medicine, Nippon Medical School Tama Nagayama Hospital
| | - Takashi Komatsu
- Division of Cardiology, Department of Internal Medicine, Iwate Medical University School of Medicine
| | | | | | - Tsuyoshi Shiga
- Department of Clinical Pharmacology and Therapeutics, The Jikei University School of Medicine
| | - Tetsuji Shinohara
- Department of Cardiology and Clinical Examination, Faculty of Medicine, Oita University
| | - Atsushi Suzuki
- Department of Cardiology, Tokyo Women's Medical University
| | - Shinya Suzuki
- Department of Cardiovascular Medicine, The Cardiovascular Institute
| | - Yukio Sekiguchi
- Department of Cardiology, National Hospital Organization Kasumigaura Medical Center
| | - Satoshi Nagase
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Noriyuki Hayami
- Department of Fourth Internal Medicine, Teikyo University Mizonokuchi Hospital
| | | | - Tadashi Fujino
- Department of Cardiovascular Medicine, Toho University, Faculty of Medicine
| | - Takeru Makiyama
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University
| | - Mitsunori Maruyama
- Department of Cardiovascular Medicine, Nippon Medical School Musashi Kosugi Hospital
| | - Junichiro Miake
- Department of Pharmacology, Tottori University Faculty of Medicine
| | - Shota Muraji
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center
| | | | - Norishige Morita
- Division of Cardiology, Department of Medicine, Tokai University Hachioji Hospital
| | - Hisashi Yokoshiki
- Department of Cardiovascular Medicine, Sapporo City General Hospital
| | - Koichiro Yoshioka
- Division of Cardiology, Department of Internal Medicine, Tokai University School of Medicine
| | - Kenji Yodogawa
- Department of Cardiovascular Medicine, Nippon Medical School
| | | | - Ken Okumura
- Division of Cardiology, Saiseikai Kumamoto Hospital Cardiovascular Center
| | - Takeshi Kimura
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School
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15
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Samuel M, Rivard L, Nault I, Gula L, Essebag V, Parkash R, Sterns LD, Khairy P, Sapp JL. Comparative effectiveness of ventricular tachycardia ablation vs. escalated antiarrhythmic drug therapy by location of myocardial infarction: a sub-study of the VANISH trial. Europace 2022; 24:948-958. [PMID: 34964475 PMCID: PMC9282915 DOI: 10.1093/europace/euab298] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/16/2021] [Indexed: 12/31/2022] Open
Abstract
AIMS Complexity of the ventricular tachycardia (VT) substrate and the size and thickness of infarction area border zones differ based on location of myocardial infarctions (MIs). These differences may translate into heterogeneity in the effectiveness of treatments. This study aims to examine the influence of infarct location on the effectiveness of VT ablation in comparison with escalated pharmacological therapy in patients with prior MI and antiarrhythmic drug (AAD)-refractory VT. METHODS AND RESULTS VANISH trial participants were categorized based on the presence or absence of an inferior MI scar. Inverse probability of treatment weighted Cox models were calculated for each subgroup. Of 259 randomized patients (median age 69.8 years, 7.0% women), 135 had an inferior MI and 124 had a non-inferior MI. Among patients with an inferior MI, no statistically significant difference in the composite primary outcome of all-cause mortality, appropriate implantable cardioverter-defibrillator (ICD) shock, and VT storm was detected between treatment arms [adjusted hazard ratio (aHR) 0.80, 95% confidence interval (CI) 0.51-1.20]. In contrast, patients with non-inferior MIs had a statistically significant reduction in the incidence of the primary outcome with ablation (aHR 0.48, 95% CI 0.27-0.86). In a sensitivity analysis of anterior MI patients (n = 83), a trend towards a reduction in the primary outcome with ablation was detected (aHR 0.50, 95% CI 0.23-1.09). CONCLUSION The effectiveness of VT ablation versus escalated AADs varies based on the location of the MI. Patients with MI scars located only in non-inferior regions of the ventricles derive greater benefit from VT ablation in comparison to escalation of AADs in reducing VT-related events.
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Affiliation(s)
- Michelle Samuel
- Department of Medicine, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada
| | - Lena Rivard
- Department of Medicine, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada
| | - Isabelle Nault
- Department of Medicine, Quebec Heart and Lung Institute, Quebec City, Quebec, Canada
| | - Lorne Gula
- Department of Medicine, Western University, London, Ontario, Canada
| | - Vidal Essebag
- Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada
| | - Ratika Parkash
- Department of Medicine, Queen Elizabeth II Health Sciences Centre, Dalhousie University, Room 2501B Halifax Infirmary, 1796 Summer St, Halifax, Nova Scotia B3H 3A7, Canada
| | - Laurence D Sterns
- Department of Medicine, Royal Jubilee Hospital, Victoria, British Columbia, Canada
| | - Paul Khairy
- Department of Medicine, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada
| | - John L Sapp
- Department of Medicine, Queen Elizabeth II Health Sciences Centre, Dalhousie University, Room 2501B Halifax Infirmary, 1796 Summer St, Halifax, Nova Scotia B3H 3A7, Canada
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Kawajiri K, Ihara K, Sasano T. Gene therapy to terminate tachyarrhythmias. Expert Rev Cardiovasc Ther 2022; 20:431-442. [PMID: 35655364 DOI: 10.1080/14779072.2022.2085686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
INTRODUCTION To date, the treatment option for tachyarrhythmia is classified into drug therapy, catheter ablation, and implantable device therapy. However, the efficacy of the antiarrhythmic drugs is limited. Although the indication of catheter ablation is expanding, several fatal tachyarrhythmias are still refractory to ablation. Implantable cardioverter-defibrillator increases survival, but it is not a curable treatment. Therefore, a novel therapy for tachyarrhythmias refractory to present treatments is desired. Gene therapy is being developed as a promising candidate for this purpose, and basic research and translational research have been accumulated in recent years. AREAS COVERED This paper reviews the current state of gene therapy for arrhythmias, including susceptible arrhythmias, the route of administration to the heart, and the type of vector to use. We also discuss the latest progress in the technology of gene delivery and genome editing. EXPERT OPINION Gene therapy is one of the most promising technologies for arrhythmia treatment. However, additional technological innovation to achieve safe, localized, homogeneous, and long-lasting gene transfer is required for its clinical application.
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Affiliation(s)
- Kohei Kawajiri
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
| | - Kensuke Ihara
- Department of Bio-informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
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17
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Daimee UA, Sung E, Engels M, Halushka MK, Berger RD, Trayanova NA, Wu KC, Chrispin J. Association of Left Ventricular Tissue Heterogeneity and Intramyocardial Fat on Computed Tomography with Ventricular Arrhythmias in Ischemic Cardiomyopathy. Heart Rhythm O2 2022; 3:241-247. [PMID: 35734302 PMCID: PMC9207722 DOI: 10.1016/j.hroo.2022.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Background Gray zone, a measure of tissue heterogeneity on late gadolinium enhanced–cardiac magnetic resonance (LGE-CMR) imaging, has been shown to predict ventricular arrhythmias (VAs) in ischemic cardiomyopathy (ICM) patients. However, no studies have described whether left ventricular (LV) tissue heterogeneity and intramyocardial fat mass on contrast-enhanced computed tomography (CE-CT), which provides greater spatial resolution, is useful for assessing the risk of VAs in ICM patients with LV systolic dysfunction and no previous VAs. Objective The purpose of this proof-of-concept study was to determine the feasibility of measuring global LV tissue heterogeneity and intramyocardial fat mass by CE-CT for predicting the risk of VAs in ICM patients with LV systolic dysfunction and no previous history of VAs. Methods Patients with left ventricular ejection fraction ≤35% and no previous VAs were enrolled in a prospective, observational registry and underwent LGE-CMR. From this cohort, patients with ICM who additionally received CE-CT were included in the present analysis. Gray zone on LGE-CMR was defined as myocardium with signal intensity (SI) > peak SI of healthy myocardium but <50% maximal SI. Tissue heterogeneity on CE-CT was defined as the standard deviation of the Hounsfield unit image gradients (HU/mm) within the myocardium. Intramyocardial fat on CE-CT was identified as regions of image pixels between –180 and –5 HU. The primary outcome was VAs, defined as appropriate implantable cardioverter-defibrillator shock or sudden arrhythmic death. Results The study consisted of 47 ICM patients, 13 (27.7%) of whom experienced VA events during mean follow-up of 5.6 ± 3.4 years. Increasing tissue heterogeneity (per HU/mm) was significantly associated with VAs after multivariable adjustment, including for gray zone (odds ratio [OR] 1.22; P = .019). Consistently, patients with tissue heterogeneity values greater than or equal to the median (≥22.2 HU/mm) had >13-fold significantly increased risk of VA events, relative to patients with values lower than the median, after multivariable adjustment that included gray zone (OR 13.13; P = .028). The addition of tissue heterogeneity to gray zone improved prediction of VAs (area under receiver operating characteristic curve increased from 0.815 to 0.876). No association was found between intramyocardial fat mass on CE-CT and VAs (OR 1.00; P = .989). Conclusion In ICM patients, CE-CT–derived LV tissue heterogeneity was independently associated with VAs and may represent a novel marker useful for risk stratification.
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18
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Krahn PRP, Biswas L, Ferguson S, Ramanan V, Barry J, Singh SM, Pop M, Wright GA. MRI-Guided Cardiac RF Ablation for Comparing MRI Characteristics of Acute Lesions and Associated Electrophysiologic Voltage Reductions. IEEE Trans Biomed Eng 2022; 69:2657-2666. [PMID: 35171765 DOI: 10.1109/tbme.2022.3152145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Objective: Radiofrequency (RF) energy delivered to cardiac tissue produces a core ablation lesion with surrounding edema, the latter of which has been implicated in acute procedural failure of Ventricular Tachycardia (VT) ablation and late arrhythmia recurrence. This study sought to investigate the electrophysiological characteristics of acute RF lesions in the left ventricle (LV) visualized with native-contrast Magnetic Resonance Imaging (MRI). Methods: An MR-guided electrophysiology system was used to deliver RF ablation in the LV of 8 swine (9 RF lesions in total), then perform MRI and electroanatomic mapping. The permanent RF lesions and transient edema were delineated via native-contrast MRI segmentation of T1-weighted images and T2 maps respectively. Bipolar voltage measurements were matched with image characteristics of pixels adjacent to the catheter tip. Native-contrast MR visualization was verified with 3D late gadolinium enhanced MRI and histology. Results: The T2-derived edema was significantly larger than the T1-derived RF lesion (2.11.5 mL compared to 0.580.34 mL; p=0.01). Bipolar voltage was significantly reduced in the presence of RF lesion core (p<0.05) and edema (p<0.05), with similar trends suggesting that both the permanent lesion and transient edema contributed to the region of reduced voltage. While bipolar voltage was significantly decreased where RF lesions are present (p<0.05), voltage did not change significantly with lesion transmurality (p>0.05). Conclusion: Permanent RF lesions and transient edema are distinct in native-contrast MR images, but not differentiable using bipolar voltage. Significance: Intraprocedural native-contrast MRI may provide valuable lesion assessment in MR-guided ablation, whose clinical application is now feasible.
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19
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Orini M, Seraphim A, Graham A, Bhuva A, Zacur E, Kellman P, Schilling R, Hunter R, Dhinoja M, Finlay MC, Ahsan S, Chow AW, Moon JC, Lambiase PD, Manisty C. Detailed Assessment of Low-Voltage Zones Localization by Cardiac MRI in Patients With Implantable Devices. JACC Clin Electrophysiol 2022; 8:225-235. [PMID: 35210080 DOI: 10.1016/j.jacep.2021.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/05/2021] [Accepted: 10/08/2021] [Indexed: 12/30/2022]
Abstract
OBJECTIVES The purpose of this study was to assess the performance and limitations of low-voltage zones (LVZ) localization by optimized late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) scar imaging in patients with cardiac implantable electronic devices (CIEDs). BACKGROUND Scar evaluation by LGE-CMR can assist ventricular tachycardia (VT) ablation, but challenges with electroanatomical maps coregistration and presence of imaging artefacts from CIED limit accuracy. METHODS A total of 10 patients underwent VT ablation and preprocedural LGE-CMR using wideband imaging. Scar was segmented from CMR pixel signal intensity maps using commercial software (ADAS-VT, Galgo Medical) with bespoke tools and compared with detailed electroanatomical maps (CARTO). Coregistration of EP and imaging-derived scar was performed using the aorta as a fiducial marker, and the impact of coregistration was determined by assessing intraobserver/interobserver variability and using computer simulations. Spatial smoothing was applied to assess correlation at different spatial resolutions and to reduce noise. RESULTS Pixel signal intensity maps localized low-voltage zones (V <1.5 mV) with area under the receiver-operating characteristic curve: 0.82 (interquartile range [IQR]: 0.76-0.83), sensitivity 74% (IQR: 71%-77%), and specificity 78% (IQR: 73%-83%) and correlated with bipolar voltage (r = -0.57 [IQR: -0.68 to -0.42]) across patients. In simulations, small random shifts and rotations worsened LVZ localization in at least some cases. The use of the full aortic geometry ensured high reproducibility of LVZ localization (r >0.86 for area under the receiver-operating characteristic curve). Spatial smoothing improved localization of LVZ. Results for LVZ with V <0.5 mV were similar. CONCLUSIONS In patients with CIEDs, novel wideband CMR sequences and personalized coregistration strategies can localize LVZ with good accuracy and may assist VT ablation procedures.
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Affiliation(s)
- Michele Orini
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Andreas Seraphim
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Adam Graham
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Anish Bhuva
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiovascular Imaging, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Ernesto Zacur
- Department of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Peter Kellman
- National Institutes of Health, Bethesda, Maryland, USA
| | - Richard Schilling
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Ross Hunter
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Mehul Dhinoja
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Malcolm C Finlay
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Syed Ahsan
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Anthony W Chow
- Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - James C Moon
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiovascular Imaging, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom
| | - Pier D Lambiase
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiac Electrophysiology, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom.
| | - Charlotte Manisty
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Cardiovascular Imaging, Barts Heart Centre, Barts Health NHS Trust, London, United Kingdom.
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20
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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: 1.0] [Reference Citation Analysis] [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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21
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Aronis KN, Okada DR, Xie E, Daimee UA, Prakosa A, Gilotra NA, Wu KC, Trayanova N, Chrispin J. Spatial dispersion analysis of LGE-CMR for prediction of ventricular arrhythmias in patients with cardiac sarcoidosis. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2021; 44:2067-2074. [PMID: 34766627 DOI: 10.1111/pace.14406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/15/2021] [Accepted: 11/07/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Patients with cardiac sarcoidosis (CS) are at increased risk of life-threatening ventricular arrhythmias (VA). Current approaches to risk stratification have limited predictive value. OBJECTIVES To assess the utility of spatial dispersion analysis of late gadolinium enhancement cardiac magnetic resonance (LGE-CMR), as a quantitative measure of myocardial tissue heterogeneity, in risk stratifying patients with CS for VA and death. METHODS Sixty two patients with CS underwent LGE-CMR. LGE images were segmented and dispersion maps of the left and right ventricles were generated as follows. Based on signal intensity (SI), each pixel was categorized as abnormal (SI ≥3SD above the mean), intermediate (SI 1-3 SD above the mean) or normal (SI <1SD above the mean); and each pixel was then assigned a value of 0 to 8 based on the number of adjacent pixels of a different category. Average dispersion score was calculated for each patient. The primary endpoint was VA during follow up. The composite of VA or death was assessed as a secondary endpoint. RESULTS During 4.7 ± 3.5 years of follow up, six patients had VA, and five without documented VA died. Average dispersion score was significantly higher in patients with VA versus those without (0.87 ± 0.08 vs. 0.71 ± 0.16; p = .002) and in patients with events versus those without (0.83 ± 0.08 vs. 0.70 ± 0.16; p = .003). Patients at higher tertiles of dispersion score had a higher incidence of VA (p = .03) and the composite of VA or death (p = .01). CONCLUSIONS Increased substrate heterogeneity, quantified by spatial dispersion analysis of LGE-CMR, may be helpful in risk-stratifying patients with CS for adverse events, including life-threatening arrhythmias.
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Affiliation(s)
- Konstantinos N Aronis
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Alliance for Cardiovascular Diagnostic and Treatment Innovation, Johns Hopkins University, Baltimore, Maryland, USA
| | - David R Okada
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Eric Xie
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Usama A Daimee
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Adityo Prakosa
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA.,Alliance for Cardiovascular Diagnostic and Treatment Innovation, Johns Hopkins University, Baltimore, Maryland, USA
| | - Nisha A Gilotra
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Katherine C Wu
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Natalia Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA.,Alliance for Cardiovascular Diagnostic and Treatment Innovation, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jonathan Chrispin
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Alliance for Cardiovascular Diagnostic and Treatment Innovation, Johns Hopkins University, Baltimore, Maryland, USA
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22
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Sahara N, Nakamura K, Toyoda Y, Enomoto Y, Kaoru S, Nakamura M. Heterogeneous scar with functional block in ventricular tachycardia circuit: Visualization of moderate high-density mapping. HeartRhythm Case Rep 2021; 7:664-668. [PMID: 34712561 PMCID: PMC8530819 DOI: 10.1016/j.hrcr.2021.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Naohiko Sahara
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Keijiro Nakamura
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Yasutake Toyoda
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Yoshinari Enomoto
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Sugi Kaoru
- Division of Cardiovascular Medicine, Odawara Cardiovascular Hospital, Kanagawa, Japan
| | - Masato Nakamura
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
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23
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Meister F, Passerini T, Audigier C, Lluch È, Mihalef V, Ashikaga H, Maier A, Halperin H, Mansi T. Extrapolation of Ventricular Activation Times From Sparse Electroanatomical Data Using Graph Convolutional Neural Networks. Front Physiol 2021; 12:694869. [PMID: 34733172 PMCID: PMC8558498 DOI: 10.3389/fphys.2021.694869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 09/15/2021] [Indexed: 11/25/2022] Open
Abstract
Electroanatomic mapping is the gold standard for the assessment of ventricular tachycardia. Acquiring high resolution electroanatomic maps is technically challenging and may require interpolation methods to obtain dense measurements. These methods, however, cannot recover activation times in the entire biventricular domain. This work investigates the use of graph convolutional neural networks to estimate biventricular activation times from sparse measurements. Our method is trained on more than 15,000 synthetic examples of realistic ventricular depolarization patterns generated by a computational electrophysiology model. Using geometries sampled from a statistical shape model of biventricular anatomy, diverse wave dynamics are induced by randomly sampling scar and border zone distributions, locations of initial activation, and tissue conduction velocities. Once trained, the method accurately reconstructs biventricular activation times in left-out synthetic simulations with a mean absolute error of 3.9 ms ± 4.2 ms at a sampling density of one measurement sample per cm2. The total activation time is matched with a mean error of 1.4 ms ± 1.4 ms. A significant decrease in errors is observed in all heart zones with an increased number of samples. Without re-training, the network is further evaluated on two datasets: (1) an in-house dataset comprising four ischemic porcine hearts with dense endocardial activation maps; (2) the CRT-EPIGGY19 challenge data comprising endo- and epicardial measurements of 5 infarcted and 6 non-infarcted swines. In both setups the neural network recovers biventricular activation times with a mean absolute error of less than 10 ms even when providing only a subset of endocardial measurements as input. Furthermore, we present a simple approach to suggest new measurement locations in real-time based on the estimated uncertainty of the graph network predictions. The model-guided selection of measurement locations allows to reduce by 40% the number of measurements required in a random sampling strategy, while achieving the same prediction error. In all the tested scenarios, the proposed approach estimates biventricular activation times with comparable or better performance than a personalized computational model and significant runtime advantages.
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Affiliation(s)
- Felix Meister
- Pattern Recognition Lab, Friedrich-Alexander University, Erlangen, Germany
- Digital Technology and Innovation, Siemens Healthineers, Erlangen, Germany
| | - Tiziano Passerini
- Digital Technology and Innovation, Siemens Healthineers, Princeton, NJ, United States
| | - Chloé Audigier
- Digital Technology and Innovation, Siemens Healthineers, Erlangen, Germany
| | - Èric Lluch
- Digital Technology and Innovation, Siemens Healthineers, Erlangen, Germany
| | - Viorel Mihalef
- Digital Technology and Innovation, Siemens Healthineers, Princeton, NJ, United States
| | - Hiroshi Ashikaga
- Cardiac Arrhythmia Service, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Andreas Maier
- Pattern Recognition Lab, Friedrich-Alexander University, Erlangen, Germany
| | - Henry Halperin
- Cardiac Arrhythmia Service, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Tommaso Mansi
- Digital Technology and Innovation, Siemens Healthineers, Princeton, NJ, United States
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24
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Aiba T. Ischemia-induced premature ventricular complexes: Is it still complex? Heart Rhythm 2021; 18:1988-1989. [PMID: 34428560 DOI: 10.1016/j.hrthm.2021.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 08/18/2021] [Indexed: 10/20/2022]
Affiliation(s)
- Takeshi Aiba
- Department of Clinical Laboratory Medicine and Genetics, National Cerebral and Cardiovascular Center, Osaka, Japan; Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan.
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25
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CMR-Based Risk Stratification of Sudden Cardiac Death and Use of Implantable Cardioverter-Defibrillator in Non-Ischemic Cardiomyopathy. Int J Mol Sci 2021; 22:ijms22137115. [PMID: 34281168 PMCID: PMC8268120 DOI: 10.3390/ijms22137115] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/27/2021] [Accepted: 06/29/2021] [Indexed: 01/04/2023] Open
Abstract
Non-ischemic cardiomyopathy (NICM) is one of the most important entities for arrhythmias and sudden cardiac death (SCD). Previous studies suggest a lower benefit of implantable cardioverter–defibrillator (ICD) therapy in patients with NICM as compared to ischemic cardiomyopathy (ICM). Nevertheless, current guidelines do not differentiate between the two subgroups in recommending ICD implantation. Hence, risk stratification is required to determine the subgroup of patients with NICM who will likely benefit from ICD therapy. Various predictors have been proposed, among others genetic mutations, left-ventricular ejection fraction (LVEF), left-ventricular end-diastolic volume (LVEDD), and T-wave alternans (TWA). In addition to these parameters, cardiovascular magnetic resonance imaging (CMR) has the potential to further improve risk stratification. CMR allows the comprehensive analysis of cardiac function and myocardial tissue composition. A range of CMR parameters have been associated with SCD. Applicable examples include late gadolinium enhancement (LGE), T1 relaxation times, and myocardial strain. This review evaluates the epidemiological aspects of SCD in NICM, the role of CMR for risk stratification, and resulting indications for ICD implantation.
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26
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Kolandaivelu A, Bruce CG, Ramasawmy R, Yildirim DK, O'Brien KJ, Schenke WH, Rogers T, Campbell-Washburn AE, Lederman RJ, Herzka DA. Native contrast visualization and tissue characterization of myocardial radiofrequency ablation and acetic acid chemoablation lesions at 0.55 T. J Cardiovasc Magn Reson 2021; 23:50. [PMID: 33952312 PMCID: PMC8101152 DOI: 10.1186/s12968-020-00693-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 12/09/2020] [Indexed: 01/18/2023] Open
Abstract
PURPOSE Low-field (0.55 T) high-performance cardiovascular magnetic resonance (CMR) is an attractive platform for CMR-guided intervention as device heating is reduced around 7.5-fold compared to 1.5 T. This work determines the feasibility of visualizing cardiac radiofrequency (RF) ablation lesions at low field CMR and explores a novel alternative method for targeted tissue destruction: acetic acid chemoablation. METHODS N = 10 swine underwent X-ray fluoroscopy-guided RF ablation (6-7 lesions) and acetic acid chemoablation (2-3 lesions) of the left ventricle. Animals were imaged at 0.55 T with native contrast 3D-navigator gated T1-weighted T1w) CMR for lesion visualization, gated single-shot imaging to determine potential for real-time visualization of lesion formation, and T1 mapping to measure change in T1 in response to ablation. Seven animals were euthanized on ablation day and hearts imaged ex vivo. The remaining animals were imaged again in vivo at 21 days post ablation to observe lesion evolution. RESULTS Chemoablation lesions could be visualized and displayed much higher contrast than necrotic RF ablation lesions with T1w imaging. On the day of ablation, in vivo myocardial T1 dropped by 19 ± 7% in RF ablation lesion cores, and by 40 ± 7% in chemoablation lesion cores (p < 4e-5). In high resolution ex vivo imaging, with reduced partial volume effects, lesion core T1 dropped by 18 ± 3% and 42 ± 6% for RF and chemoablation, respectively. Mean, median, and peak lesion signal-to-noise ratio (SNR) were all at least 75% higher with chemoablation. Lesion core to myocardium contrast-to-noise (CNR) was 3.8 × higher for chemoablation. Correlation between in vivo and ex vivo CMR and histology indicated that the periphery of RF ablation lesions do not exhibit changes in T1 while the entire extent of chemoablation exhibits T1 changes. Correlation of T1w enhancing lesion volumes indicated in vivo estimates of lesion volume are accurate for chemoablation but underestimate extent of necrosis for RF ablation. CONCLUSION The visualization of coagulation necrosis from cardiac ablation is feasible using low-field high-performance CMR. Chemoablation produced a more pronounced change in lesion T1 than RF ablation, increasing SNR and CNR and thereby making it easier to visualize in both 3D navigator-gated and real-time CMR and more suitable for low-field imaging.
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Affiliation(s)
- Aravindan Kolandaivelu
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chris G Bruce
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Rajiv Ramasawmy
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- Biophysics and Biochemistry Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Dursun Korel Yildirim
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- Institute of Biomedical Engineering, Bogazici University, Istanbul, Turkey
| | - Kendall J O'Brien
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - William H Schenke
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Toby Rogers
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- Medstar Washington Hospital Center, Washington, DC, USA
| | - Adrienne E Campbell-Washburn
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
- Biophysics and Biochemistry Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robert J Lederman
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Daniel A Herzka
- Cardiovascular Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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27
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Kotake Y, Nalliah CJ, Campbell T, Trivic I, Ross N, Bennett RG, Turnbull S, Kumar S. Epicardial-Endocardial Reentry in Ischemic Cardiomyopathy. J Innov Card Rhythm Manag 2021; 12:4467-4472. [PMID: 33936862 PMCID: PMC8081459 DOI: 10.19102/icrm.2021.120402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 12/28/2020] [Indexed: 11/06/2022] Open
Abstract
In ischemic cardiomyopathy, endocardial reentry has traditionally been the mechanistic paradigm for understanding ventricular tachycardia (VT). However, recognition is growing that epicardial myocardium is a critical component for VT substrate, even in patients with ischemic cardiomyopathy. In this report, we present a novel case of a three-dimensional VT reentry involving epicardial components and an endocardial exit.
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Affiliation(s)
- Yasuhito Kotake
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Chrishan J Nalliah
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Timothy Campbell
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Ivana Trivic
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Neil Ross
- Department of Cardiology, Westmead Hospital, Sydney, Australia
| | - Richard G Bennett
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Samual Turnbull
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
| | - Saurabh Kumar
- Department of Cardiology, Westmead Hospital, Sydney, Australia.,Westmead Applied Research Centre, University of Sydney, New South Wales, Australia
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28
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Berruezo A, Penela D, Jáuregui B, Soto-Iglesias D. The role of imaging in catheter ablation of ventricular arrhythmias. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2021; 44:1115-1125. [PMID: 33527461 DOI: 10.1111/pace.14183] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 01/15/2021] [Accepted: 01/24/2021] [Indexed: 02/01/2023]
Abstract
Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) and multidetector cardiac computed tomography (MDCT) have emerged as novel, fascinating imaging tools for arrhythmogenic substrate identification and characterization. The role of these techniques for aiding and guiding the catheter ablation of ventricular tachycardia, either as a complement or a surrogate of the electroanatomic map, has been rising in recent years. Integrating pixel signal intensity maps or wall thickness maps delivered from LGE-CMR or MDCT, respectively, into the navigation system has become a cornerstone for VT ablation procedures in a few centers of excellence around the world. The pre-procedure scar characterization offers some advantages, helping decide for the best procedure planning and approach; complete substrate identification and characterization, helping to focus electroanatomical mapping in regions of interest and also has a positive impact in procedure efficiency and outcomes. In the present article, we perform a review of the most practical aspects for using LGE-CMR or MDCT when a VT ablation procedure is planned, from the image acquisition to the integration into the navigation system, analyzing the current role of the LGE-CMR and MDCT for arrhythmogenic substrate characterization as well as for guiding VT ablation.
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Affiliation(s)
| | - Diego Penela
- Heart Institute, Teknon Medical Center, Barcelona, Spain
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29
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Thavapalachandran S, Grieve SM, Hume RD, Le TYL, Raguram K, Hudson JE, Pouliopoulos J, Figtree GA, Dye RP, Barry AM, Brown P, Lu J, Coffey S, Kesteven SH, Mills RJ, Rashid FN, Taran E, Kovoor P, Thomas L, Denniss AR, Kizana E, Asli NS, Xaymardan M, Feneley MP, Graham RM, Harvey RP, Chong JJH. Platelet-derived growth factor-AB improves scar mechanics and vascularity after myocardial infarction. Sci Transl Med 2021; 12:12/524/eaay2140. [PMID: 31894101 DOI: 10.1126/scitranslmed.aay2140] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022]
Abstract
Therapies that target scar formation after myocardial infarction (MI) could prevent ensuing heart failure or death from ventricular arrhythmias. We have previously shown that recombinant human platelet-derived growth factor-AB (rhPDGF-AB) improves cardiac function in a rodent model of MI. To progress clinical translation, we evaluated rhPDGF-AB treatment in a clinically relevant porcine model of myocardial ischemia-reperfusion. Thirty-six pigs were randomized to sham procedure or balloon occlusion of the proximal left anterior descending coronary artery with 7-day intravenous infusion of rhPDGF-AB or vehicle. One month after MI, rhPDGF-AB improved survival by 40% compared with vehicle, and cardiac magnetic resonance imaging showed left ventricular (LV) ejection fraction improved by 11.5%, driven by reduced LV end-systolic volumes. Pressure volume loop analyses revealed improved myocardial contractility and energetics after rhPDGF-AB treatment with minimal effect on ventricular compliance. rhPDGF-AB enhanced angiogenesis and increased scar anisotropy (high fiber alignment) without affecting overall scar size or stiffness. rhPDGF-AB reduced inducible ventricular tachycardia by decreasing heterogeneity of the ventricular scar that provides a substrate for reentrant circuits. In summary, we demonstrated that rhPDGF-AB promotes post-MI cardiac wound repair by altering the mechanics of the infarct scar, resulting in robust cardiac functional improvement, decreased ventricular arrhythmias, and improved survival. Our findings suggest a strong translational potential for rhPDGF-AB as an adjunct to current MI treatment and possibly to modulate scar in other organs.
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Affiliation(s)
- Sujitha Thavapalachandran
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia.,Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Stuart M Grieve
- Sydney Translational Imaging Laboratory, Heart Research Institute, Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia
| | - Robert D Hume
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia
| | - Thi Yen Loan Le
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia
| | - Kalyan Raguram
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia
| | - James E Hudson
- QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia
| | - Jim Pouliopoulos
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Gemma A Figtree
- Kolling Institute of Medical Research, The University of Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
| | - Rafael P Dye
- Kolling Institute of Medical Research, The University of Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
| | - Anthony M Barry
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Paula Brown
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Juntang Lu
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Sean Coffey
- Kolling Institute of Medical Research, The University of Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia.,Department of Medicine, Dunedin School of Medicine, Dunedin Hospital, Dunedin 9016, New Zealand
| | - Scott H Kesteven
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Richard J Mills
- QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia
| | - Fairooj N Rashid
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia
| | - Elena Taran
- Australian National Fabrication Facility-Queensland Node, The University of Queensland, St. Lucia, QLD 4072, Australia.,School of Chemical Engineering, University of Melbourne, VIC 3010, Australia
| | - Pramesh Kovoor
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Liza Thomas
- Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | | | - Eddy Kizana
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia.,Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
| | - Naisana S Asli
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,Faculty of Medicine and Health, University of Sydney, Westmead Hospital, Westmead, NSW 2145, Australia.,Centre for Cancer Research, The Westmead Institute for Medical Research, Sydney, NSW 2145, Australia
| | - Munira Xaymardan
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Michael P Feneley
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St. Vincent's Clinical School, UNSW Sydney, Kensington, NSW 2052, Australia
| | - Robert M Graham
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St. Vincent's Clinical School, UNSW Sydney, Kensington, NSW 2052, Australia
| | - Richard P Harvey
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St. Vincent's Clinical School, UNSW Sydney, Kensington, NSW 2052, Australia.,School of Biotechnology and Biomolecular Science, UNSW Sydney, Kensington, NSW 2052, Australia
| | - James J H Chong
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia. .,Department of Cardiology, Westmead Hospital, Westmead, NSW 2145, Australia
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Zhang L, Lai P, Roifman I, Pop M, Wright GA. Multi-contrast volumetric imaging with isotropic resolution for assessing infarct heterogeneity: Initial clinical experience. NMR IN BIOMEDICINE 2020; 33:e4253. [PMID: 32026547 DOI: 10.1002/nbm.4253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 11/14/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND To evaluate accelerated multi-contrast volumetric imaging with isotropic resolution reconstructed using low-rank and spatially varying edge-preserving constrained compressed sensing parallel imaging reconstruction (CP-LASER), for assessing infarct heterogeneity on post-infarction patients as a precursor to studies of utility for predicting ventricular arrhythmias. METHODS Eleven patients with prior myocardial infarction were included in the study. All subjects underwent cardiovascular magnetic resonance (CMR) scans including conventional two-dimensional late gadolinium enhancement (2D LGE) and three-dimensional multi-contrast late enhancement (3D MCLE) post-contrast. The extent of the infarct core and peri-infarct gray zone of a limited mid-ventricular slab were derived respectively by analyzing MCLE images with an isotropic resolution of 2.2 mm and an anisotropic resolution of 2.2×2.2×8.8 mm 3 , and LGE images with a resolution of 1.37×2.7×8 mm 3 ; the respective measures across all subjects were statistically compared. RESULTS Using 3D MCLE, the infarct core size measured with isotropic resolution was similar to that measured with anisotropic resolution, while the peri-infarct gray zone size measured with isotropic resolution was smaller than that measured with anisotropic resolution ( p<0.001 , Cohen's dz=1.33 ). Isotropic 3D MCLE yielded a significantly smaller measure of the peri-infarct gray zone size than conventional 2D LGE ( p=0.0016 , Cohen's dz=1.20 ). Overall, we have successfully shown the utility of isotropic 3D MCLE in a pilot patient study. Our results suggest that smaller voxels lead to more accurate differentiation between isotropic 3D MCLE-derived gray zone and core infarct because of diminished partial volume effect. CONCLUSION The CP-LASER accelerated 3D MCLE with isotropic resolution can be used in patients and yields excellent delineation of infarct and peri-infarct gray zone characteristics.
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Affiliation(s)
- Li Zhang
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Peng Lai
- Global Applied Science Laboratory, GE Healthcare, Menlo Park, California, USA
| | - Idan Roifman
- Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Mihaela Pop
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Graham A Wright
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Schulich Heart Research Program, Sunnybrook Research Institute, Toronto, Ontario, Canada
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31
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Ghonim S, Ernst S, Keegan J, Giannakidis A, Spadotto V, Voges I, Smith GC, Boutsikou M, Montanaro C, Wong T, Ho SY, McCarthy KP, Shore DF, Dimopoulos K, Uebing A, Swan L, Li W, Pennell DJ, Gatzoulis MA, Babu-Narayan SV. Three-Dimensional Late Gadolinium Enhancement Cardiovascular Magnetic Resonance Predicts Inducibility of Ventricular Tachycardia in Adults With Repaired Tetralogy of Fallot. Circ Arrhythm Electrophysiol 2020; 13:e008321. [PMID: 33022183 DOI: 10.1161/circep.119.008321] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Adults with repaired tetralogy of Fallot die prematurely from ventricular tachycardia (VT) and sudden cardiac death. Inducible VT predicts mortality. Ventricular scar, the key substrate for VT, can be noninvasively defined with late gadolinium enhancement (LGE) cardiovascular magnetic resonance but whether this relates to inducible VT is unknown. METHODS Sixty-nine consecutive repaired tetralogy of Fallot patients (43 male, mean 40±15 years) clinically scheduled for invasive programmed VT-stimulation were prospectively recruited for prior 3-dimensional LGE cardiovascular magnetic resonance. Ventricular LGE was segmented and merged with reconstructed cardiac chambers and LGE volume measured. RESULTS VT was induced in 22 (31%) patients. Univariable predictors of inducible VT included increased RV LGE (odds ratio [OR], 1.15; P=0.001 per cm3), increased nonapical vent LV LGE (OR, 1.09; P=0.008 per cm3), older age (OR, 1.6; P=0.01 per decile), QRS duration ≥180 ms (OR, 3.5; P=0.02), history of nonsustained VT (OR, 3.5; P=0.02), and previous clinical sustained VT (OR, 12.8; P=0.003); only prior sustained VT (OR, 8.02; P=0.02) remained independent in bivariable analyses after controlling for RV LGE volume (OR, 1.14; P=0.003). An RV LGE volume of 25 cm3 had 72% sensitivity and 81% specificity for predicting inducible VT (area under the curve, 0.81; P<0.001). At the extreme cutoffs for ruling-out and ruling-in inducible VT, RV LGE >10 cm3 was 100% sensitive and >36 cm3 was 100% specific for predicting inducible VT. CONCLUSIONS Three-dimensional LGE cardiovascular magnetic resonance-defined scar burden is independently associated with inducible VT and may help refine patient selection for programmed VT-stimulation when applied to an at least intermediate clinical risk cohort.
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Affiliation(s)
- Sarah Ghonim
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Sabine Ernst
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Jenny Keegan
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Archontis Giannakidis
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Veronica Spadotto
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Inga Voges
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Gillian C Smith
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Maria Boutsikou
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Claudia Montanaro
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Tom Wong
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Siew Yen Ho
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Karen P McCarthy
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Darryl F Shore
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Konstantinos Dimopoulos
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Anselm Uebing
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Lorna Swan
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Wei Li
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Dudley J Pennell
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Michael A Gatzoulis
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
| | - Sonya V Babu-Narayan
- Royal Brompton Hospital (S.G., S.E., J.K., A.G., V.S., I.V., G.C.S., M.B., C.M., T.W., S.Y.H., K.P.M., D.F.S., K.D., A.U., L.S., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom.,National Heart & Lung Institute, Imperial College (S.G., S.E., J.K., A.G., T.W., S.Y.H., K.D., W.L., D.J.P., M.A.G., S.V.B.-N.), London, United Kingdom
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Kucukseymen S, Yavin H, Barkagan M, Jang J, Shapira-Daniels A, Rodriguez J, Shim D, Pashakhanloo F, Pierce P, Botzer L, Manning WJ, Anter E, Nezafat R. Discordance in Scar Detection Between Electroanatomical Mapping and Cardiac MRI in an Infarct Swine Model. JACC Clin Electrophysiol 2020; 6:1452-1464. [DOI: 10.1016/j.jacep.2020.08.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/29/2020] [Accepted: 08/11/2020] [Indexed: 12/18/2022]
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Malaczynska-Rajpold K, Blaszyk K, Kociemba A, Pyda M, Posadzy-Malaczynska A, Grajek S. Islets of heterogeneous myocardium within the scar in cardiac magnetic resonance predict ventricular tachycardia after myocardial infarction. J Cardiovasc Electrophysiol 2020; 31:1452-1461. [PMID: 32227520 DOI: 10.1111/jce.14461] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 03/06/2020] [Accepted: 03/24/2020] [Indexed: 11/30/2022]
Abstract
INTRODUCTION We assessed findings in cardiac magnetic resonance (CMR) as predictors of ventricular tachycardia (VT) after myocardial infarction (MI), which could allow for more precise identification of patients at risk of sudden cardiac death. METHODS Forty-eight patients after prior MI were enrolled and divided into two groups: with (n = 24) and without (n = 24) VT. VT was confirmed by electrophysiological study and exit site was estimated based on 12-lead electrocardiogram. All patients underwent CMR with late gadolinium enhancement. RESULTS The examined groups did not differ significantly in clinical and demographical parameters (including LV ejection fraction). There was a significant difference in the infarct age between the VT and non-VT group (15.8 ± 8.4 vs 7.1 ± 6.7 years, respectively; P = .002), with the cut-off point at the level of 12 years. In the scar core, islets of heterogeneous myocardium were revealed. They were defined as areas of potentially viable myocardium within or adjacent to the core scar. The number of islets was the strongest independent predictor of VT (odds ratio [OR], 1.42; confidence interval [CI], 1.17-1.73), but total islet size and the largest islet area were also significantly higher in the VT group (OR, 1.04; CI, 1.02-1.07 and OR, 1.16; CI, 1.01-1.27, respectively). Myocardial segments with fibrosis forming 25%-75% of the ventricular wall were associated with a higher incidence of VT (7.5 ± 2.1 vs 5.7 ± 2.6; P = .014). Three-dimension CMR reconstruction confirmed good correlation of the location of the islets/channels with VT exit site during electroanatomical mapping in five cases. CONCLUSIONS The identification and quantification of islets of heterogeneous myocardium within the scar might be useful for predicting VT in patients after MI.
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Affiliation(s)
- Katarzyna Malaczynska-Rajpold
- Heart Division, Royal Brompton & Harefield NHS Foundation Trust, London, UK.,1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
| | - Krzysztof Blaszyk
- 1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
| | - Anna Kociemba
- 1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland.,Heart Division, Affidea International Oncology Centre, Poznan, Poland
| | - Malgorzata Pyda
- 1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Stefan Grajek
- 1st Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland
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34
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Okada DR, Miller J, Chrispin J, Prakosa A, Trayanova N, Jones S, Maggioni M, Wu KC. Substrate Spatial Complexity Analysis for the Prediction of Ventricular Arrhythmias in Patients With Ischemic Cardiomyopathy. Circ Arrhythm Electrophysiol 2020; 13:e007975. [PMID: 32188287 PMCID: PMC7207018 DOI: 10.1161/circep.119.007975] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Transition zones between healthy myocardium and scar form a spatially complex substrate that may give rise to reentrant ventricular arrhythmias (VAs). We sought to assess the utility of a novel machine learning approach for quantifying 3-dimensional spatial complexity of grayscale patterns on late gadolinium enhanced cardiac magnetic resonance images to predict VAs in patients with ischemic cardiomyopathy. METHODS One hundred twenty-two consecutive ischemic cardiomyopathy patients with left ventricular ejection fraction ≤35% without prior history of VAs underwent late gadolinium enhanced cardiac magnetic resonance images. From raw grayscale data, we generated graphs encoding the 3-dimensional geometry of the left ventricle. A novel technique, adapted to these graphs, assessed global regularity of signal intensity patterns using Fourier-like analysis and generated a substrate spatial complexity profile for each patient. A machine learning statistical algorithm was employed to discern which substrate spatial complexity profiles correlated with VA events (appropriate implantable cardioverter-defibrillator firings and arrhythmic sudden cardiac death) at 5 years of follow-up. From the statistical machine learning results, a complexity score ranging from 0 to 1 was calculated for each patient and tested using multivariable Cox regression models. RESULTS At 5 years of follow-up, 40 patients had VA events. The machine learning algorithm classified with 81% overall accuracy and correctly classified 86% of those without VAs. Overall negative predictive value was 91%. Average complexity score was significantly higher in patients with VA events versus those without (0.5±0.5 versus 0.1±0.2; P<0.0001) and was independently associated with VA events in a multivariable model (hazard ratio, 1.5 [1.2-2.0]; P=0.002). CONCLUSIONS Substrate spatial complexity analysis of late gadolinium enhanced cardiac magnetic resonance images may be helpful in refining VA risk in patients with ischemic cardiomyopathy, particularly to identify low-risk patients who may not benefit from prophylactic implantable cardioverter-defibrillator therapy. Visual Overview: A visual overview is available for this article.
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Affiliation(s)
- David R Okada
- Division of Cardiology, Department of Medicine (D.R.O., J.C., S.J., K.C.W.)
| | | | - Jonathan Chrispin
- Division of Cardiology, Department of Medicine (D.R.O., J.C., S.J., K.C.W.)
| | | | | | - Steven Jones
- Division of Cardiology, Department of Medicine (D.R.O., J.C., S.J., K.C.W.)
| | - Mauro Maggioni
- Department of Applied Mathematics (J.A., M.M.).,Department of Mathematics, Johns Hopkins University, Baltimore, MD (M.M.)
| | - Katherine C Wu
- Division of Cardiology, Department of Medicine (D.R.O., J.C., S.J., K.C.W.)
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Vunnam R, Maheshwari V, Jeudy J, Ghzally Y, Imanli H, Abdulghani M, Mahat JB, Timilsina S, Restrepo A, See V, Shorofsky S, Dickfeld T. Ventricular arrhythmia ablation lesions detectability and temporal changes on cardiac magnetic resonance. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2020; 43:314-321. [DOI: 10.1111/pace.13886] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/09/2020] [Accepted: 02/03/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Rama Vunnam
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Varun Maheshwari
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Jean Jeudy
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Department of Diagnostic Radiology and Nuclear MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Yousra Ghzally
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Hasan Imanli
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Mohammed Abdulghani
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Jagat B. Mahat
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Saroj Timilsina
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Alejandro Restrepo
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Vincent See
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Stephen Shorofsky
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
| | - Timm Dickfeld
- Maryland Arrhythmia and Cardiology Imaging Group Baltimore Maryland
- Division of Cardiology, Department of MedicineUniversity of Maryland School of Medicine Baltimore Maryland
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Dries E, Amoni M, Vandenberk B, Johnson DM, Gilbert G, Nagaraju CK, Puertas RD, Abdesselem M, Santiago DJ, Roderick HL, Claus P, Willems R, Sipido KR. Altered adrenergic response in myocytes bordering a chronic myocardial infarction underlies in vivo triggered activity and repolarization instability. J Physiol 2020; 598:2875-2895. [PMID: 31900932 PMCID: PMC7496440 DOI: 10.1113/jp278839] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 01/01/2020] [Indexed: 01/24/2023] Open
Abstract
Key points
Ventricular arrhythmias are a major complication after myocardial infarction (MI), associated with sympathetic activation. The structurally heterogeneous peri‐infarct zone is a known substrate, but the functional role of the myocytes is less well known. Recordings of monophasic action potentials in vivo reveal that the peri‐infarct zone is a source of delayed afterdepolarizations (DADs) and has a high beat‐to‐beat variability of repolarization (BVR) during adrenergic stimulation (isoproterenol, ISO). Myocytes isolated from the peri‐infarct region have more DADs and spontaneous action potentials, with spontaneous Ca2+ release, under ISO. These myocytes also have reduced repolarization reserve and increased BVR. Other properties of post‐MI remodelling are present in both peri‐infarct and remote myocytes. These data highlight the importance of altered myocyte adrenergic responses in the peri‐infarct region as source and substrate of post‐MI arrhythmias. Abstract Ventricular arrhythmias are a major early complication after myocardial infarction (MI). The heterogeneous peri‐infarct zone forms a substrate for re‐entry while arrhythmia initiation is often associated with sympathetic activation. We studied the mechanisms triggering these post‐MI arrhythmias in vivo and their relation to regional myocyte remodelling. In pigs with chronic MI (6 weeks), in vivo monophasic action potentials were simultaneously recorded in the peri‐infarct and remote regions during adrenergic stimulation with isoproterenol (isoprenaline; ISO). Sham animals served as controls. During infusion of ISO in vivo, the incidence of delayed afterdepolarizations (DADs) and beat‐to‐beat variability of repolarization (BVR) was higher in the peri‐infarct than in the remote region. Myocytes isolated from the peri‐infarct region, in comparison to myocytes from the remote region, had more DADs, associated with spontaneous Ca2+ release, and a higher incidence of spontaneous action potentials (APs) when exposed to ISO (9.99 ± 4.2 vs. 0.16 ± 0.05 APs/min, p = 0.004); these were suppressed by CaMKII inhibition. Peri‐infarct myocytes also had reduced repolarization reserve and increased BVR (26 ± 10 ms vs. 9 ± 7 ms, P < 0.001), correlating with DAD activity. In contrast to these regional distinctions under ISO, alterations in Ca2+ handling at baseline and myocyte hypertrophy were present throughout the left ventricle (LV). Expression of some of the related genes was, however, different between the regions. In conclusion, altered myocyte adrenergic responses in the peri‐infarct but not the remote region provide a source of triggered activity in vivo and of repolarization instability amplifying the substrate for re‐entry. These findings stimulate further exploration of region‐specific therapies targeting myocytes and autonomic modulation.
Ventricular arrhythmias are a major complication after myocardial infarction (MI), associated with sympathetic activation. The structurally heterogeneous peri‐infarct zone is a known substrate, but the functional role of the myocytes is less well known. Recordings of monophasic action potentials in vivo reveal that the peri‐infarct zone is a source of delayed afterdepolarizations (DADs) and has a high beat‐to‐beat variability of repolarization (BVR) during adrenergic stimulation (isoproterenol, ISO). Myocytes isolated from the peri‐infarct region have more DADs and spontaneous action potentials, with spontaneous Ca2+ release, under ISO. These myocytes also have reduced repolarization reserve and increased BVR. Other properties of post‐MI remodelling are present in both peri‐infarct and remote myocytes. These data highlight the importance of altered myocyte adrenergic responses in the peri‐infarct region as source and substrate of post‐MI arrhythmias.
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Affiliation(s)
- Eef Dries
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Matthew Amoni
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Bert Vandenberk
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Daniel M Johnson
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium.,Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Guillaume Gilbert
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Chandan K Nagaraju
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Rosa Doñate Puertas
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Mouna Abdesselem
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Demetrio J Santiago
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium.,Laboratory of Molecular Cardiology, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), C. Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - H Llewelyn Roderick
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Piet Claus
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Rik Willems
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
| | - Karin R Sipido
- Experimental Cardiology, University of Leuven, Herestraat 49 box 911, Leuven, Belgium
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Abstract
Ventricular tachycardia is typically hemodynamically unstable. Strategies to target the arrhythmogenic substrate during sinus rhythm are essential for therapeutic ablation. Electroanatomic mapping is the cornerstone of substrate-based strategies; ablation can be directed within a delineated scar region defined by low voltage. Bipolar voltage mapping has inherent limitations. Specific electrogram characteristics may improve the specificity of localizing the most arrhythmogenic regions within the substrate. Deceleration zones during sinus rhythm are niduses for reentry and can be identified by isochronal late activation mapping, which is a functional analysis of substrate propagation with local annotation to electrogram offset.
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Affiliation(s)
- Roderick Tung
- Department of Medicine, Section of Cardiology, The University of Chicago Medicine, Center for Arrhythmia Care, Pritzker School of Medicine, 5841 South Maryland Avenue, MC 6080, Chicago, IL 60637, USA.
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Trew ML, Engelman ZJ, Caldwell BJ, Lever NA, LeGrice IJ, Smaill BH. Cardiac intramural electrical mapping reveals focal delays but no conduction velocity slowing in the peri-infarct region. Am J Physiol Heart Circ Physiol 2019; 317:H743-H753. [PMID: 31419152 DOI: 10.1152/ajpheart.00154.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Altered electrical behavior alongside healed myocardial infarcts (MIs) is associated with increased risk of sudden cardiac death. However, the multidimensional mechanisms are poorly understood and described. This study characterizes, for the first time, the intramural spread of electrical activation in the peri-infarct region of chronic reperfusion MIs. Four sheep were studied 13 wk after antero-apical reperfusion infarction. Extracellular potentials (ECPs) were recorded in a ~20 × 20-mm2 region adjacent to the infarct boundary (25 plunge needles <0.5-mm diameter with 15 electrodes at 1-mm centers) during multisite stimulation. Infarct geometry and electrode locations were reconstructed from magnetic resonance images. Three-dimensional activation spread was characterized by local activation times and interpolated ECP fields (n = 191 records). Control data were acquired in 4 non-infarcted sheep (n = 96 records). Electrodes were distributed uniformly around 15 ± 5% of the intramural infarct boundary. There were marked changes in pacing success and ECP morphology across a functional border zone (BZ) ±2 mm from the boundary. Stimulation adjacent to the infarct boundary was associated with low-amplitude electrical activity within the BZ and delayed activation of surrounding myocardium. Bulk tissue depolarization occurred 3.5-14.6 mm from the pacing site for 39% of stimuli with delays of 4-37 ms, both significantly greater than control (P < 0.0001). Conduction velocity (CV) adjacent to the infarct was not reduced compared with control, consistent with structure-only computer model results. Insignificant CV slowing, irregular stimulus-site specific activation delays, and obvious indirect activation pathways strongly suggest that the substrate for conduction abnormalities in chronic MI is predominantly structural in nature.NEW & NOTEWORTHY Intramural in vivo measurements of peri-infarct electrical activity were not available before this study. We use pace-mapping in a three-dimensional electrode array to show that a subset of stimuli in the peri-infarct region initiates coordinated myocardial activation some distance from the stimulus site with substantial associated time delays. This is site dependent and heterogeneous and occurs for <50% of ectopic stimuli in the border zone. Furthermore, once coordinated activation is initiated, conduction velocity adjacent to the infarct boundary is not significantly different from control. These results give new insights to peri-infarct electrical activity and do not support the widespread view of uniform electrical remodeling in the border zone of chronic myocardial infarcts, with depressed conduction velocity throughout.
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Affiliation(s)
- Mark L Trew
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Zoar J Engelman
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Bryan J Caldwell
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Nigel A Lever
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.,Auckland Hospital, Auckland, New Zealand
| | - Ian J LeGrice
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.,Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Bruce H Smaill
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.,Department of Physiology, University of Auckland, Auckland, New Zealand
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39
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Abstract
Cardiac fibrosis is a significant increase in collagen volume fraction of myocardial tissue. It plays an important role in the pathophysiology of many cardiovascular abnormalities. Electrophysiologically, myocardial fibrosis produces anisotropic conduction, inhomogeneity, and conduction delay. Several markers are available to detect myocardial fibrosis. CMRI is the most common imaging technique; late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) provides markers for tissue characterization, disease progression and arrhythmic events. LGE-CMR can be used as risk marker of occurrence of pathologic conditions. LGE-CMR demonstrates specific patterns related to different pathologic substrates. We discuss the role of CMRI in ventricular arrhythmogenesis.
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Affiliation(s)
- Mohammad Shenasa
- Heart and Rhythm Medical Group, Department of Cardiovascular Services, O'Connor Hospital, San Jose, CA 95030, USA.
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40
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Pashakhanloo F, Herzka DA, Halperin H, McVeigh ER, Trayanova NA. Role of 3-Dimensional Architecture of Scar and Surviving Tissue in Ventricular Tachycardia: Insights From High-Resolution Ex Vivo Porcine Models. Circ Arrhythm Electrophysiol 2019; 11:e006131. [PMID: 29880529 DOI: 10.1161/circep.117.006131] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 04/05/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND An improved knowledge of the spatial organization of infarct structure and its contribution to ventricular tachycardia (VT) is important for designing optimal treatments. This study explores the relationship between the 3-dimensional structure of the healed infarct and the VT reentrant pathways in high-resolution models of infarcted porcine hearts. METHODS Structurally detailed models of infarcted ventricles were reconstructed from ex vivo late gadolinium enhancement and diffusion tensor magnetic resonance imaging data of 8 chronically infarcted porcine hearts at submillimeter resolution (0.25×0.25×0.5 mm3). To characterize the 3-dimensional structure of surviving tissue in the zone of infarct, a novel scar-mapped thickness metric was introduced. Further, using the ventricular models, electrophysiological simulations were conducted to determine and analyze the 3-dimensional VT pathways that were established in each of the complex infarct morphologies. RESULTS The scar-mapped thickness metric revealed the heterogeneous organization of infarct and enabled us to systematically characterize the distribution of surviving tissue thickness in 8 hearts. Simulation results demonstrated the involvement of a subendocardial tissue layer of varying thickness in the majority of VT pathways. Importantly, they revealed that VT pathways are most frequently established within thin surviving tissue structures of thickness ≤2.2 mm (90th percentile) surrounding the scar. CONCLUSIONS The combination of high-resolution imaging data and ventricular simulations revealed the 3-dimensional distribution of surviving tissue surrounding the scar and demonstrated its involvement in VT pathways. The new knowledge obtained in this study contributes toward a better understanding of infarct-related VT.
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Affiliation(s)
| | - Daniel A Herzka
- Department of Biomedical Engineering (F.P., D.A.H., E.R.M., N.A.T.)
| | | | - Elliot R McVeigh
- Department of Biomedical Engineering (F.P., D.A.H., E.R.M., N.A.T.).,Johns Hopkins University, Baltimore, MD. Departments of Bioengineering, Medicine, and Radiology, University of California, San Diego, La Jolla (E.R.M.)
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41
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Okada DR, Wu KC. Applications of Cardiac MR Imaging in Electrophysiology. Magn Reson Imaging Clin N Am 2019; 27:465-473. [PMID: 31279450 DOI: 10.1016/j.mric.2019.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Deng D, Prakosa A, Shade J, Nikolov P, Trayanova NA. Characterizing Conduction Channels in Postinfarction Patients Using a Personalized Virtual Heart. Biophys J 2019; 117:2287-2294. [PMID: 31447108 DOI: 10.1016/j.bpj.2019.07.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 06/25/2019] [Accepted: 07/10/2019] [Indexed: 01/22/2023] Open
Abstract
Patients with myocardial infarction have an abundance of conduction channels (CC); however, only a small subset of these CCs sustain ventricular tachycardia (VT). Identifying these critical CCs (CCCs) in the clinic so that they can be targeted by ablation remains a significant challenge. The objective of this study is to use a personalized virtual-heart approach to conduct a three-dimensional (3D) assessment of CCCs sustaining VTs of different morphologies in these patients, to investigate their 3D structural features, and to determine the optimal ablation strategy for each VT. To achieve these goals, ventricular models were constructed from contrast enhanced magnetic resonance imagings of six postinfarction patients. Rapid pacing induced VTs in each model. CCCs that sustained different VT morphologies were identified. CCCs' 3D structure and type and the resulting rotational electrical activity were examined. Ablation was performed at the optimal part of each CCC, aiming to terminate each VT with a minimal lesion size. Predicted ablation locations were compared to clinical. Analyzing the simulation results, we found that the observed VTs in each patient model were sustained by a limited number (2.7 ± 1.2) of CCCs. Further, we identified three types of CCCs sustaining VTs: I-type and T-type channels, with all channel branches bounded by scar, and functional reentry channels, which were fully or partially bounded by conduction block surfaces. The different types of CCCs accounted for 43.8, 18.8, and 37.4% of all CCCs, respectively. The mean narrowest width of CCCs or a branch of CCC was 9.7 ± 3.6 mm. Ablation of the narrowest part of each CCC was sufficient to terminate VT. Our results demonstrate that a personalized virtual-heart approach can determine the possible VT morphologies in each patient and identify the CCCs that sustain reentry. The approach can aid clinicians in identifying accurately the optimal VT ablation targets in postinfarction patients.
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Affiliation(s)
- Dongdong Deng
- School of Biomedical Engineering, Dalian University of Technology, Dalian, Liaoning, China; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Adityo Prakosa
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Julie Shade
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Plamen Nikolov
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Natalia A Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
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43
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Dhanjal TS, Lellouche N, von Ruhland CJ, Abehsira G, Edwards DH, Dubois-Randé JL, Moschonas K, Teiger E, Williams AJ, George CH. Massive Accumulation of Myofibroblasts in the Critical Isthmus Is Associated With Ventricular Tachycardia Inducibility in Post-Infarct Swine Heart. JACC Clin Electrophysiol 2019; 3:703-714. [PMID: 28770255 PMCID: PMC5527067 DOI: 10.1016/j.jacep.2016.11.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Objectives In this study the authors determined the extent of cellular infiltration and dispersion, and regional vascularization in electrophysiologically (EP) defined zones in post–myocardial infarction (MI) swine ventricle. Background The critical isthmus (CI) in post-MI re-entrant ventricular tachycardia (VT) is a target for catheter ablation. In vitro evidence suggests that myofibroblasts (MFB) within the scar border zone (BZ) may increase the susceptibility to slow conduction and VT, but whether this occurs in vivo remains unproven. Methods Six weeks after mid–left anterior descending coronary artery occlusion, EP catheter-based mapping was used to assess susceptibility to VT induction. EP data were correlated with detailed cellular profiling of ventricular zones using immunohistochemistry and spatial distribution analysis of cardiomyocytes, fibroblasts, MFB, and vascularization. Results In pigs with induced sustained monomorphic VT (mean cycle length: 353 ± 89 ms; n = 6) the area of scar that consisted of the BZ (i.e., between the normal and the low-voltage area identified by substrate mapping) was greater in VT-inducible hearts (iVT) than in noninducible hearts (non-VT) (p < 0.05). Scar in iVT hearts was characterized by MFB accumulation in the CI (>100 times that in normal myocardium and >5 times higher than that in the BZ in non-VT hearts) and by a 1.7-fold increase in blood vessel density within the dense scar region extending towards the CI. Sites of local abnormal ventricular activity potentials exhibited cellularity and vascularization that were intermediate to the CI in iVT and BZ in non-VT hearts. Conclusions The authors reported the first cellular analysis of the VT CI following an EP-based zonal analysis of iVT and non-VT hearts in pigs post-MI. The data suggested that VT susceptibility was defined by a remarkable number of MFB in the VT CI, which appeared to bridge the few remaining dispersed clusters of cardiomyocytes. These findings define the cellular substrate for the proarrhythmic slow conduction pathway.
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Key Words
- BZ, border zone
- CI, critical isthmus
- CM, cardiomyocytes
- ECM, extracellular matrix
- EP, electrophysiology
- FB, fibroblasts
- IHC, immunohistochemistry
- LAD, left anterior descending
- LAVA, local abnormal ventricular activity
- MFB, myofibroblasts
- MI, myocardial infarction
- MRI, magnetic resonance imaging
- VT
- VT, ventricular tachycardia
- Vim, vimentin
- border zone
- cTnT, cardiac troponin T
- critical isthmus
- iVT, inducible ventricular tachycardia
- myocardial infarction
- myofibroblasts
- pig
- vWF, von Willebrand factor
- α-SMA, α-smooth muscle actin
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Affiliation(s)
- Tarvinder S. Dhanjal
- School of Medicine, Cardiff University, Cardiff, Wales, United Kingdom
- Hôpital Henri Mondor Albert Chenevier, DHU-ATVB, Inserm U955, IMRB, University Paris Est Creteil Paris XII, Paris, France
| | - Nicolas Lellouche
- Hôpital Henri Mondor Albert Chenevier, DHU-ATVB, Inserm U955, IMRB, University Paris Est Creteil Paris XII, Paris, France
| | | | - Guillaume Abehsira
- Hôpital Henri Mondor Albert Chenevier, DHU-ATVB, Inserm U955, IMRB, University Paris Est Creteil Paris XII, Paris, France
| | - David H. Edwards
- School of Medicine, Cardiff University, Cardiff, Wales, United Kingdom
- Institute of Life Sciences, Swansea University Medical School, Swansea, Wales, United Kingdom
| | - Jean-Luc Dubois-Randé
- Hôpital Henri Mondor Albert Chenevier, DHU-ATVB, Inserm U955, IMRB, University Paris Est Creteil Paris XII, Paris, France
| | | | - Emmanuel Teiger
- Hôpital Henri Mondor Albert Chenevier, DHU-ATVB, Inserm U955, IMRB, University Paris Est Creteil Paris XII, Paris, France
| | - Alan J. Williams
- School of Medicine, Cardiff University, Cardiff, Wales, United Kingdom
- Institute of Life Sciences, Swansea University Medical School, Swansea, Wales, United Kingdom
| | - Christopher H. George
- School of Medicine, Cardiff University, Cardiff, Wales, United Kingdom
- Institute of Life Sciences, Swansea University Medical School, Swansea, Wales, United Kingdom
- Address for correspondence: Dr. Christopher H. George, Swansea University Medical School, Institute of Life Sciences, Singleton Park, Swansea, Wales SA2 8PP, United Kingdom.Swansea University Medical SchoolInstitute of Life Sciences, Singleton ParkSwanseaWales SA2 8PPUnited Kingdom
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44
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Jang J, Hwang HJ, Tschabrunn CM, Whitaker J, Menze B, Anter E, Nezafat R. Cardiovascular Magnetic Resonance-Based Three-Dimensional Structural Modeling and Heterogeneous Tissue Channel Detection in Ventricular Arrhythmia. Sci Rep 2019; 9:9317. [PMID: 31249352 PMCID: PMC6597699 DOI: 10.1038/s41598-019-45586-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/05/2019] [Indexed: 11/25/2022] Open
Abstract
Geometrical structure of the myocardium plays an important role in understanding the generation of arrhythmias. In particular, a heterogeneous tissue (HT) channel defined in cardiovascular magnetic resonance (CMR) has been suggested to correlate with conduction channels defined in electroanatomic mapping in ventricular tachycardia (VT). Despite the potential of CMR for characterization of the arrhythmogenic substrate, there is currently no standard approach to identify potential conduction channels. Therefore, we sought to develop a workflow to identify HT channel based on the structural 3D modeling of the viable myocardium within areas of dense scar. We focus on macro-level HT channel detection in this work. The proposed technique was tested in high-resolution ex-vivo CMR images in 20 post-infarct swine models who underwent an electrophysiology study for VT inducibility. HT channel was detected in 15 animals with inducible VT, whereas it was only detected in 1 out of 5 animal with non-inducible VT (P < 0.01, Fisher’s exact test). The HT channel detected in the non-inducible animal was shorter than those detected in animals with inducible VTs (inducible-VT animals: 35 ± 14 mm vs. non-inducible VT animal: 9.94 mm). Electrophysiology study and histopathological analyses validated the detected HT channels. The proposed technique may provide new insights for understanding the macro-level VT mechanism.
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Affiliation(s)
- Jihye Jang
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.,Department of Computer Science, Technical University of Munich, Munich, Germany
| | - Hye-Jin Hwang
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Cory M Tschabrunn
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.,Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John Whitaker
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.,Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom
| | - Bjoern Menze
- Department of Computer Science, Technical University of Munich, Munich, Germany
| | - Elad Anter
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Reza Nezafat
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
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45
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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: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [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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46
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Mukherjee RK, Roujol S, Chubb H, Harrison J, Williams S, Whitaker J, O'Neill L, Silberbauer J, Neji R, Schneider R, Pohl T, Lloyd T, O'Neill M, Razavi R. Epicardial electroanatomical mapping, radiofrequency ablation, and lesion imaging in the porcine left ventricle under real-time magnetic resonance imaging guidance-an in vivo feasibility study. Europace 2019; 20:f254-f262. [PMID: 29294008 PMCID: PMC6140436 DOI: 10.1093/europace/eux341] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/16/2017] [Indexed: 12/03/2022] Open
Abstract
Aims Magnetic resonance imaging (MRI) is the gold standard for defining myocardial substrate in 3D and can be used to guide ventricular tachycardia ablation. We describe the feasibility of using a prototype magnetic resonance-guided electrophysiology (MR-EP) system in a pre-clinical model to perform real-time MRI-guided epicardial mapping, ablation, and lesion imaging with active catheter tracking. Methods and results Experiments were performed in vivo in pigs (n = 6) using an MR-EP guidance system research prototype (Siemens Healthcare) with an irrigated ablation catheter (Vision-MR, Imricor) and a dedicated electrophysiology recording system (Advantage-MR, Imricor). Following epicardial access, local activation and voltage maps were acquired, and targeted radiofrequency (RF) ablation lesions were delivered. Ablation lesions were visualized in real time during RF delivery using MR-thermometry and dosimetry. Hyper-acute and acute assessment of ablation lesions was also performed using native T1 mapping and late-gadolinium enhancement (LGE), respectively. High-quality epicardial bipolar electrograms were recorded with a signal-to-noise ratio of greater than 10:1 for a signal of 1.5 mV. During epicardial ablation, localized temperature elevation could be visualized with a maximum temperature rise of 35 °C within 2 mm of the catheter tip relative to remote myocardium. Decreased native T1 times were observed (882 ± 107 ms) in the lesion core 3–5 min after lesion delivery and relative location of lesions matched well to LGE. There was a good correlation between ablation lesion site on the iCMR platform and autopsy. Conclusion The MR-EP system was able to successfully acquire epicardial voltage and activation maps in swine, deliver, and visualize ablation lesions, demonstrating feasibility for intraprocedural guidance and real-time assessment of ablation injury.
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Affiliation(s)
- Rahul K Mukherjee
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - Sébastien Roujol
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - Henry Chubb
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - James Harrison
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - Steven Williams
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - John Whitaker
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - Louisa O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - John Silberbauer
- Department of Cardiology, Brighton and Sussex University Hospital NHS Trust, Eastern Road, Brighton, UK
| | - Radhouene Neji
- Siemens Healthcare, Sir William Siemens Square, Frimley, Camberley, UK
| | | | | | - Tom Lloyd
- Imricor Medical Systems, 400 Gateway Blvd, Burnsville, MN, USA
| | - Mark O'Neill
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
| | - Reza Razavi
- Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London, UK
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47
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Lopez-Perez A, Sebastian R, Izquierdo M, Ruiz R, Bishop M, Ferrero JM. Personalized Cardiac Computational Models: From Clinical Data to Simulation of Infarct-Related Ventricular Tachycardia. Front Physiol 2019; 10:580. [PMID: 31156460 PMCID: PMC6531915 DOI: 10.3389/fphys.2019.00580] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 04/25/2019] [Indexed: 12/20/2022] Open
Abstract
In the chronic stage of myocardial infarction, a significant number of patients develop life-threatening ventricular tachycardias (VT) due to the arrhythmogenic nature of the remodeled myocardium. Radiofrequency ablation (RFA) is a common procedure to isolate reentry pathways across the infarct scar that are responsible for VT. Unfortunately, this strategy show relatively low success rates; up to 50% of patients experience recurrent VT after the procedure. In the last decade, intensive research in the field of computational cardiac electrophysiology (EP) has demonstrated the ability of three-dimensional (3D) cardiac computational models to perform in-silico EP studies. However, the personalization and modeling of certain key components remain challenging, particularly in the case of the infarct border zone (BZ). In this study, we used a clinical dataset from a patient with a history of infarct-related VT to build an image-based 3D ventricular model aimed at computational simulation of cardiac EP, including detailed patient-specific cardiac anatomy and infarct scar geometry. We modeled the BZ in eight different ways by combining the presence or absence of electrical remodeling with four different levels of image-based patchy fibrosis (0, 10, 20, and 30%). A 3D torso model was also constructed to compute the ECG. Patient-specific sinus activation patterns were simulated and validated against the patient's ECG. Subsequently, the pacing protocol used to induce reentrant VTs in the EP laboratory was reproduced in-silico. The clinical VT was induced with different versions of the model and from different pacing points, thus identifying the slow conducting channel responsible for such VT. Finally, the real patient's ECG recorded during VT episodes was used to validate our simulation results and to assess different strategies to model the BZ. Our study showed that reduced conduction velocities and heterogeneity in action potential duration in the BZ are the main factors in promoting reentrant activity. Either electrical remodeling or fibrosis in a degree of at least 30% in the BZ were required to initiate VT. Moreover, this proof-of-concept study confirms the feasibility of developing 3D computational models for cardiac EP able to reproduce cardiac activation in sinus rhythm and during VT, using exclusively non-invasive clinical data.
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Affiliation(s)
- Alejandro Lopez-Perez
- Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, Valencia, Spain
| | - Rafael Sebastian
- Computational Multiscale Simulation Lab (CoMMLab), Universitat de València, Valencia, Spain
| | - M Izquierdo
- INCLIVA Health Research Institute, Valencia, Spain.,Arrhythmia Unit, Cardiology Department, Hospital Clínico Universitario de Valencia, Valencia, Spain
| | - Ricardo Ruiz
- INCLIVA Health Research Institute, Valencia, Spain.,Arrhythmia Unit, Cardiology Department, Hospital Clínico Universitario de Valencia, Valencia, Spain
| | - Martin Bishop
- Division of Imaging Sciences & Biomedical Engineering, Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Jose M Ferrero
- Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, Valencia, Spain
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48
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Kawamura I, Fukamizu S, Arai M, Inagaki D, Miyabe T, Miyazawa S, Kitamura T, Hojo R, Nishizaki M, Sakurada H, Hiraoka M. Characteristics of ventricular intracardiac electrograms of ventricular tachycardias originating from the epicardia in patients with an implantable cardioverter defibrillator. J Cardiovasc Electrophysiol 2019; 30:575-581. [PMID: 30710406 DOI: 10.1111/jce.13854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/27/2018] [Accepted: 01/07/2019] [Indexed: 11/30/2022]
Abstract
INTRODUCTION While characteristic waveforms of 12-lead electrocardiograms have been reported to predict the epicardial origin of ventricular tachycardia (VT), it has not been fully examined whether ventricular intracardiac electrograms (VEGMs) recorded from the implantable cardioverter defibrillator (ICD) via telemetry can determine the origin of VT or not. The aim of this study was to investigate the VEGM characteristics of VT originating from the epicardia. METHOD AND RESULTS Intracardiac VEGMs of the induced VTs, with detected sites of origin during the VT study, were recorded in 15 (23 VTs) of the 46 patients. The characteristics of the 23 VTs were evaluated using far-field and near-field VEGMs recorded via telemetry. Five of 23 VTs were found to be focused on the epicardial site (epi group) and 18 VTs were focused on the endocardium (endo group). VTs of the epi group had longer VEGM duration in far-field EGM than those of the endo group (epi group: 240 ± 49 ms vs endo group: 153 ± 45 ms; P = 0.002) and the duration from the onset to the peak of VEGM was also longer than that of the endo group (epi group: 153 ± 53 ms vs endo group: 63 ± 28 ms; P < 0.001). There was no difference in the V wave duration in tip-ring EGM between both groups (epi group: 122 ± 52 ms vs endo group: 98 ± 6 ms; P = 0.377). CONCLUSION Evaluation of intracardiac VEGM before VT ablation may be helpful to predict the epicardial origin of VT in patients with an ICD.
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Affiliation(s)
- Iwanari Kawamura
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Seiji Fukamizu
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Marina Arai
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Dai Inagaki
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Tomonori Miyabe
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Satoshi Miyazawa
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Takeshi Kitamura
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Rintaro Hojo
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Mitsuhiro Nishizaki
- Health Care Center, Internal Medicine and Cardiology, Kanto Gakuin University, Yokohama, Kanagawa, Japan
| | - Harumizu Sakurada
- Department of Cardiology, Tokyo Metropolitan Health and Medical Treatment Corporation Ohkubo Hospital, Tokyo, Japan
| | - Masayasu Hiraoka
- Department of Cardiology, Tokyo Medical and Dental, University, Tokyo, Japan
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49
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Nayyar S, Downar E, Beheshti M, Liang T, Massé S, Magtibay K, Bhaskaran A, Saeed Y, Vigmond E, Nanthakumar K. Information theory to tachycardia therapy: electrogram entropy predicts diastolic microstructure of reentrant ventricular tachycardia. Am J Physiol Heart Circ Physiol 2019; 316:H134-H144. [DOI: 10.1152/ajpheart.00581.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is no known strategy to differentiate which multicomponent electrograms in sinus rhythm maintain reentrant ventricular tachycardia (VT). Low entropy in the voltage breakdown of a multicomponent electrogram can localize conditions suitable for reentry but has not been validated against the classic VT activation mapping. We examined whether low entropy in a late and diversely activated ventricular scar region characterizes and differentiates the diastolic path of VT and represents protected tissue channels devoid of side branches. Intraoperative bipolar electrogram (BiEGM) activation and entropy maps were obtained during sinus rhythm in 17 patients with ischemic cardiomyopathy and compared with diastolic activation paths of VT (total of 39 VTs). Mathematical modeling of a zigzag main channel with side branches was also used to further validate structural representation of low entropy in the ventricular scar. A median of one region per patient (range: 1–2 regions) was identified in sinus rhythm, in which BiEGMwith the latest mean activation time and adjacent minimum entropy were assembled together in a high-activation dispersion region. These regions accurately recognized diastolic paths of 34 VTs, often to multiple inducible VTs within a single individual arrhythmogenic region. In mathematical modeling, side branching from the main channel had a strong influence on the BiEGMcomposition along the main channel. The BiEGMobtained from a long unbranched channel had the lowest entropy compared with those with multiple side branches. In conclusion, among a population of multicomponent sinus electrograms, those that demonstrate low entropy and are delayed colocalize to critical long-protected channels of VT. This information is pertinent for planning VT ablation in sinus rhythm.NEW & NOTEWORTHY Entropy is a measure to quantify breakdown in information. Electrograms from a protected tissue channel can only possess a few states in their voltage and thus less information. In contrast, current-load interactions from side branches in unprotected channels introduce a number of dissimilar voltage deflections and thus high information. We compare here a mapping approach based on entropy against a rigorous reference standard of activation mapping during VT and entropy was assessed in sinus rhythm.
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Affiliation(s)
- Sachin Nayyar
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Eugene Downar
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Mohammadali Beheshti
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Timothy Liang
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Stéphane Massé
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Karl Magtibay
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Abhishek Bhaskaran
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Yawer Saeed
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
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50
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Tao S, Guttman MA, Fink S, Elahi H, Patil KD, Ashikaga H, Kolandaivelu AD, Berger RD, Halushka MK, Schmidt EJ, Herzka DA, Halperin HR. Ablation Lesion Characterization in Scarred Substrate Assessed Using Cardiac Magnetic Resonance. JACC Clin Electrophysiol 2018; 5:91-100. [PMID: 30678791 DOI: 10.1016/j.jacep.2018.11.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 10/30/2018] [Accepted: 11/01/2018] [Indexed: 11/18/2022]
Abstract
OBJECTIVES This study examined radiofrequency catheter ablation (RFCA) lesions within and around scar by cardiac magnetic resonance (CMR) imaging and histology. BACKGROUND Substrate modification by RFCA is the cornerstone therapy for ventricular arrhythmias. RFCA in scarred myocardium, however, is not well understood. METHODS We performed electroanatomic mapping and RFCA in the left ventricles of 8 swine with myocardial infarction. Non-contrast-enhanced T1-weighted (T1w) and contrast-enhanced CMR after RFCA were compared with gross pathology and histology. RESULTS Of 59 lesions, 17 were in normal myocardium (voltage >1.5 mV), 21 in border zone (0.5 to 1.5 mV), and 21 in scar (<0.5 mV). All RFCA lesions were enhanced in T1w CMR, whereas scar was hypointense, allowing discrimination among normal myocardium, scar, and RFCA lesions. With contrast-enhancement, lesions and scar were similarly enhanced and not distinguishable. Lesion width and depth in T1w CMR correlated with necrosis in pathology (both; r2 = 0.94, p < 0.001). CMR lesion volume was significantly different in normal myocardium, border zone, and scar (median: 397 [interquartile range (IQR): 301 to 474] mm3, 121 [IQR: 87 to 201] mm3, 66 [IQR: 33 to 123] mm3, respectively). RFCA force-time integral, impedance, and voltage changes did not correlate with lesion volume in border zone or scar. Histology showed that ablation necrosis extended into fibrotic tissue in 26 lesions and beyond in 14 lesions. In 7 lesions, necrosis expansion was blocked and redirected by fat. CONCLUSIONS T1w CMR can selectively enhance necrotic tissue in and around scar and may allow determination of the completeness of ablation intra- and post-procedure. Lesion formation in scar is affected by tissue characteristics, with fibrosis and fat acting as thermal insulators.
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Affiliation(s)
- Susumu Tao
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
| | - Michael A Guttman
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sarah Fink
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hassan Elahi
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Kaustubha D Patil
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hiroshi Ashikaga
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Aravindan D Kolandaivelu
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ronald D Berger
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Marc K Halushka
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ehud J Schmidt
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Daniel A Herzka
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Henry R Halperin
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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