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Dennis ASC, Orini M, Melis Hesselkilde E, Saljic A, Linz BM, Sattler SM, Williams J, Tfelt-Hansen J, Jespersen T, Chow AWC, Lambiase PD. Impact of Multidirectional Pacing on Activation and Repolarization Parameters to Localize Ischemic Ventricular Tachycardia Circuits. JACC Clin Electrophysiol 2024:S2405-500X(24)00764-3. [PMID: 39453293 DOI: 10.1016/j.jacep.2024.07.028] [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: 03/25/2024] [Revised: 07/09/2024] [Accepted: 07/29/2024] [Indexed: 10/26/2024]
Abstract
BACKGROUND In ventricular tachycardia (VT), optimal substrate mapping strategies identifying arrhythmogenic sites are not established. OBJECTIVES This study sought to evaluate multidirectional pacing on the distribution of specific conduction and repolarization metrics to localize re-entrant VT sites in a porcine infarct model. METHODS Substrate maps were created in 13 pigs with chronic myocardial infarction using the Advisor HD Grid (Abbott) during right ventricular (RV), left ventricular, biventricular pacing (BIV), and sinus rhythm (SR). Critical VT sites of early-, mid-, and late-diastolic signals were delineated. Vulnerable sites to re-entry were defined as sites of latest activation timing within and post-QRS complex, largest activation and activation-recovery interval gradients. Distances between the 20 most vulnerable sites and diastolic VT points were measured, and identification of VT points was assessed using the area under the receiver-operating characteristic curve. RESULTS A total of 34 VTs were mapped, and 48 sinus and pacing maps were obtained (10 BIV, 13 left ventricular, 13 RV, 12 SR). Late potential mapping in SR was taken as the established clinical standard for comparison. Latest activation time with BIV pacing provided the closest localization for VT isthmus (median 5.5 mm; IQR: 7.15 mm; P < 0.005). The gradient of activation-recovery interval using RV pacing had closest localization for VT exit and entrance (median 10.6 mm; IQR: 5.0 mm; P < 0.005 and 9.4 mm; IQR: 8.0 mm; P < 0.05). Global sensitivity and specificity analysis showed that gradient of activation-recovery interval in SR achieved the highest area under the receiver-operating characteristic curve, with similar results from the gradient of activation timing. CONCLUSIONS Multidirectional pacing in combination with conduction and repolarization parameters enables better localization of VT diastolic critical sites vs SR late potentials.
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Affiliation(s)
- Adam S C Dennis
- Centre for Translational Electrophysiology, Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Electrophysiology, Barts Heart Centre, St. Bartholomew's Hospital, London, United Kingdom
| | - Michele Orini
- Centre for Translational Electrophysiology, Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Eva Melis Hesselkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Arnela Saljic
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Benedikt M Linz
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Stefan M Sattler
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Cardiology, Herlev and Gentofte University Hospital, Copenhagen, Denmark
| | - James Williams
- Abbott Medical United Kingdom, Blythe Valley Park, Solihull, United Kingdom
| | - Jacob Tfelt-Hansen
- Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen and Department of Cardiology, Heart Centre Copenhagen University Hospital, Copenhagen, Denmark
| | - Thomas Jespersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anthony W C Chow
- Department of Electrophysiology, Barts Heart Centre, St. Bartholomew's Hospital, London, United Kingdom; Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Pier D Lambiase
- Centre for Translational Electrophysiology, Institute of Cardiovascular Science, University College London, London, United Kingdom; Department of Electrophysiology, Barts Heart Centre, St. Bartholomew's Hospital, London, United Kingdom.
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2
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Lambiase PD. Can an S3 Extrastimulus Light the Way for More Targeted VT Substrate Ablation? JACC Clin Electrophysiol 2024; 10:1548-1550. [PMID: 39084735 DOI: 10.1016/j.jacep.2024.05.025] [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: 05/10/2024] [Accepted: 05/25/2024] [Indexed: 08/02/2024]
Affiliation(s)
- Pier D Lambiase
- Institute of Cardiovascular Science, University College London, Barts Heart Centre, London, United Kingdom.
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3
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Nitta T, Asano T, Yajima T, Otsuka T, Ishii Y. Chemical ablation of the left ventricular endocardium reduces ventricular fibrillation inducibility in acute ischemic canine heart. J Arrhythm 2024; 40:325-332. [PMID: 38586838 PMCID: PMC10995593 DOI: 10.1002/joa3.12993] [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: 12/04/2023] [Revised: 12/24/2023] [Accepted: 01/08/2024] [Indexed: 04/09/2024] Open
Abstract
Objective Ventricular fibrillation remains as the major cause of death in patients with acute myocardial infarction. Effects of trans-atrial chemical ablation of the left ventricular (LV) endocardium with Lugol's solution on ventricular fibrillation inducibility and ventricular conduction were examined in canines with acute myocardial ischemia. Materials and Methods Chemical ablation of the LV endocardium with Lugol's solution or normal saline was preformed through a left atrial appendage in 14 canines 30 min after occlusion of the left anterior coronary artery. Results Ventricular fibrillation threshold decreased after the coronary artery occlusion and increased after endocardial chemical ablation. There was a significant difference in the ventricular fibrillation threshold after chemical ablation between with Lugol's solution and with normal saline (25.9 ± 9.2 mA vs. 11.3 ± 2.7 mA, p < .01). QRS width significantly increased from 88 ± 4 msec to 116 ± 5 msec (p < .01) after the chemical ablation with Lugol's solution, and the activation map of the ventricles demonstrated a left bundle branch block ventricular conduction pattern. Histological examination of the LV endocardium showed lymphocyte infiltration for a depth of 1 mm. Conclusions Chemical ablation of the LV endocardium with Lugol's solution injures endocardial conduction system and increases ventricular fibrillation threshold in the early phase of myocardial ischemia in canines. The procedure may be useful in suppressing intractable ventricular tachyarrhythmias in patients with acute myocardial ischemia.
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Affiliation(s)
- Takashi Nitta
- Cardiovascular SurgeryNippon Medical SchoolTokyoJapan
| | - Tetsuo Asano
- Cardiovascular SurgeryNippon Medical SchoolTokyoJapan
| | | | - Toshiaki Otsuka
- Public Health (Statistical Analysis)Nippon Medical SchoolTokyoJapan
| | - Yosuke Ishii
- Cardiovascular SurgeryNippon Medical SchoolTokyoJapan
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4
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van der Waal J, Meijborg V, Coronel R, Dubois R, Oostendorp T. Basis and applicability of noninvasive inverse electrocardiography: a comparison between cardiac source models. Front Physiol 2023; 14:1295103. [PMID: 38152249 PMCID: PMC10752226 DOI: 10.3389/fphys.2023.1295103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 11/30/2023] [Indexed: 12/29/2023] Open
Abstract
The body surface electrocardiogram (ECG) is a direct result of electrical activity generated by the myocardium. Using the body surface ECGs to reconstruct cardiac electrical activity is called the inverse problem of electrocardiography. The method to solve the inverse problem depends on the chosen cardiac source model to describe cardiac electrical activity. In this paper, we describe the theoretical basis of two inverse methods based on the most commonly used cardiac source models: the epicardial potential model and the equivalent dipole layer model. We discuss similarities and differences in applicability, strengths and weaknesses and sketch a road towards improved inverse solutions by targeted use, sequential application or a combination of the two methods.
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Affiliation(s)
- Jeanne van der Waal
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - Veronique Meijborg
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - Ruben Coronel
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - Rémi Dubois
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac, France
| | - Thom Oostendorp
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, Netherlands
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5
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Porta-Sánchez A, Mazzanti A, Tarifa C, Kukavica D, Trancuccio A, Mohsin M, Zanfrini E, Perota A, Duchi R, Hernandez-Lopez K, Jáuregui-Abularach ME, Pergola V, Fernandez E, Bongianino R, Tavazzani E, Gambelli P, Memmi M, Scacchi S, Pavarino LF, Franzone PC, Lentini G, Filgueiras-Rama D, Galli C, Santiago DJ, Priori SG. Unexpected impairment of INa underpins reentrant arrhythmias in a knock-in swine model of Timothy syndrome. NATURE CARDIOVASCULAR RESEARCH 2023; 2:1291-1309. [PMID: 38665938 PMCID: PMC11041658 DOI: 10.1038/s44161-023-00393-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 11/15/2023] [Indexed: 04/28/2024]
Abstract
Timothy syndrome 1 (TS1) is a multi-organ form of long QT syndrome associated with life-threatening cardiac arrhythmias, the organ-level dynamics of which remain unclear. In this study, we developed and characterized a novel porcine model of TS1 carrying the causative p.Gly406Arg mutation in CACNA1C, known to impair CaV1.2 channel inactivation. Our model fully recapitulated the human disease with prolonged QT interval and arrhythmic mortality. Electroanatomical mapping revealed the presence of a functional substrate vulnerable to reentry, stemming from an unforeseen constitutional slowing of cardiac activation. This signature substrate of TS1 was reliably identified using the reentry vulnerability index, which, we further demonstrate, can be used as a benchmark for assessing treatment efficacy, as shown by testing of multiple clinical and preclinical anti-arrhythmic compounds. Notably, in vitro experiments showed that TS1 cardiomyocytes display Ca2+ overload and decreased peak INa current, providing a rationale for the arrhythmogenic slowing of impulse propagation in vivo.
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Affiliation(s)
- Andreu Porta-Sánchez
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Andrea Mazzanti
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Carmen Tarifa
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Deni Kukavica
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Alessandro Trancuccio
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Muhammad Mohsin
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
| | | | | | | | - Kevin Hernandez-Lopez
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | | | - Valerio Pergola
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy
| | - Eugenio Fernandez
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Rossana Bongianino
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
| | - Elisa Tavazzani
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
| | - Patrick Gambelli
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
| | - Mirella Memmi
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
| | - Simone Scacchi
- Department of Mathematics, University of Milan, Milano, Italy
| | | | - Piero Colli Franzone
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- AVANTEA, Cremona, Italy
- Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy
- Department of Mathematics, University of Milan, Milano, Italy
- Department of Mathematics, University of Pavia, Pavia, Italy
- Department of Pharmacology, University of Bari, Bari, Italy
- Cardiovascular Institute, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares, Madrid, Spain
| | | | - David Filgueiras-Rama
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Cardiovascular Institute, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares, Madrid, Spain
| | | | - Demetrio Julián Santiago
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Silvia G. Priori
- Novel Arrhythmogenic Mechanism Program, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Molecular Cardiology, IRCCS Istituti Clinici Scientifici Maugeri, Pavia, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
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6
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Baldazzi G, Orrù M, Viola G, Pani D. Computer-aided detection of arrhythmogenic sites in post-ischemic ventricular tachycardia. Sci Rep 2023; 13:6906. [PMID: 37106017 PMCID: PMC10140038 DOI: 10.1038/s41598-023-33866-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 04/20/2023] [Indexed: 04/29/2023] Open
Abstract
Nowadays, catheter-based ablation in patients with post-ischemic ventricular tachycardia (VT) is performed in arrhythmogenic sites identified by electrophysiologists by visual inspection during electroanatomic mapping. This work aims to present the development of machine learning tools aiming at supporting clinicians in the identification of arrhythmogenic sites by exploiting innovative features that belong to different domains. This study included 1584 bipolar electrograms from nine patients affected by post-ischemic VT. Different features were extracted in the time, time scale, frequency, and spatial domains and used to train different supervised classifiers. Classification results showed high performance, revealing robustness across the different classifiers in terms of accuracy, true positive, and false positive rates. The combination of multi-domain features with the ensemble tree is the most effective solution, exhibiting accuracies above 93% in the 10-time 10-fold cross-validation and 84% in the leave-one-subject-out validation. Results confirmed the effectiveness of the proposed features and their potential use in a computer-aided system for the detection of arrhythmogenic sites. This work demonstrates for the first time the usefulness of supervised machine learning for the detection of arrhythmogenic sites in post-ischemic VT patients, thus enabling the development of computer-aided systems to reduce operator dependence and errors, thereby possibly improving clinical outcomes.
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Affiliation(s)
- Giulia Baldazzi
- Medical Devices and Signal Processing (MeDSP) Lab, Department of Electrical and Electronic Engineering (DIEE), University of Cagliari, Cagliari, Italy.
- Department of Informatics, Bioengineering, Robotics and Systems Engineering (DIBRIS), University of Genoa, Genoa, Italy.
| | - Marco Orrù
- Medical Devices and Signal Processing (MeDSP) Lab, Department of Electrical and Electronic Engineering (DIEE), University of Cagliari, Cagliari, Italy
- Department of Informatics, Bioengineering, Robotics and Systems Engineering (DIBRIS), University of Genoa, Genoa, Italy
| | - Graziana Viola
- Department of Cardiology, Santissima Annunziata Hospital, Sassari, Italy
| | - Danilo Pani
- Medical Devices and Signal Processing (MeDSP) Lab, Department of Electrical and Electronic Engineering (DIEE), University of Cagliari, Cagliari, Italy
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7
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Davies MJ, Bradfield JS. A Virtual Step Toward Precision Scar-Related Ventricular Tachycardia Ablation. JACC Clin Electrophysiol 2023; 9:311-313. [PMID: 36990594 DOI: 10.1016/j.jacep.2023.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 03/29/2023]
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8
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Anderson RD, Nayyar S, Masse S, Lambiase PD, Nanthakumar K. Wave tail mapping to guide ablation therapy for ventricular arrhythmias. Heart Rhythm 2023; 20:461-470. [PMID: 36756940 DOI: 10.1016/j.hrthm.2022.10.020] [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: 08/11/2022] [Revised: 10/13/2022] [Accepted: 10/24/2022] [Indexed: 12/23/2022]
Affiliation(s)
- Robert D Anderson
- Hull Family Cardiac Fibrillation Management Laboratory, Division of Cardiology, University Health Network, Toronto General Hospital, Toronto, Ontario, Canada
| | - Sachin Nayyar
- Department of Cardiology, Townsville University Hospital, James Cook University, Douglas, Queensland, Australia
| | - Stephane Masse
- Hull Family Cardiac Fibrillation Management Laboratory, Division of Cardiology, University Health Network, Toronto General Hospital, Toronto, Ontario, Canada
| | - Pier D Lambiase
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom; Institute of Cardiovascular Science, University College London, London, United Kingdom
| | - Kumaraswamy Nanthakumar
- Hull Family Cardiac Fibrillation Management Laboratory, Division of Cardiology, University Health Network, Toronto General Hospital, Toronto, Ontario, Canada.
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9
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Retrospective Window of Interest Annotation Provides New Insights Into Functional Channels in Ventricular Tachycardia Substrate. JACC Clin Electrophysiol 2023; 9:1-16. [PMID: 36697187 DOI: 10.1016/j.jacep.2022.10.025] [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: 07/07/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 01/24/2023]
Abstract
BACKGROUND Accurate annotation of local activation time is crucial in the functional assessment of ventricular tachycardia (VT) substrate. A major limitation of modern mapping systems is the standard prospective window of interest (sWOI) is limited to 490 to 500 milliseconds, preventing annotation of very late potentials (LPs). A novel retrospective window of interest (rWOI), which allows annotation of all diastolic potentials, was used to assess the functional VT substrate. OBJECTIVES This study sought to investigate the utility of a novel rWOI, which allows accurate visualization and annotation of all LPs during VT substrate mapping. METHODS Patients with high-density VT substrate maps and a defined isthmus were included. All electrograms were manually annotated to latest activation using a novel rWOI. Reannotated substrate maps were correlated to critical sites, with areas of late activation examined. Propagation patterns were examined to assess the functional aspects of the VT substrate. RESULTS Forty-eight cases were identified with 1,820 ± 826 points per map. Using the novel rWOI, 31 maps (65%) demonstrated LPs beyond the sWOI limit. Two distinct patterns of channel activation were seen during substrate mapping: 1) functional block with unidirectional conduction into the channel (76%); and 2) wave front collision within the channel (24%). In addition, a novel marker termed the zone of early and late crowding was studied in the rWOI substrate maps and found to have a higher positive predictive value (85%) than traditional deceleration zones (69%) for detecting critical sites of re-entry. CONCLUSIONS The standard WOI of contemporary mapping systems is arbitrarily limited and results in important very late potentials being excluded from annotation. Future versions of electroanatomical mapping systems should provide longer WOIs for accurate local activation time annotation.
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10
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Computational Re-Entry Vulnerability Index Mapping to Guide Ablation in Patients With Post-Myocardial Infarction Ventricular Tachycardia. JACC Clin Electrophysiol 2022; 9:301-310. [PMID: 36752477 DOI: 10.1016/j.jacep.2022.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/07/2022] [Accepted: 10/03/2022] [Indexed: 12/02/2022]
Abstract
BACKGROUND Ventricular tachycardias (VTs) in patients with myocardial infarction (MI) are often treated with catheter ablation. However, the VT induction during this procedure does not always identify all of the relevant activation pathways or may not be possible or tolerated. The re-entry vulnerability index (RVI) quantifies regional activation-repolarization differences and can detect multiple regions susceptible to re-entry without the need to induce the arrhythmia. OBJECTIVES This study aimed to further develop and validate the RVI mapping in patient-specific computational models of post-MI VTs. METHODS Cardiac magnetic resonance imaging data from 4 patients with post-MI VTs were used to induce VTs in a computational electrophysiological model by pacing. The RVI map of a premature beat in each patient model was used to guide virtual ablations. We compared our results with those of clinical ablation in the same patients. RESULTS Single-site virtual RVI-guided ablation prevented VT induction in 3 of 9 cases. Multisite virtual ablations guided by RVI mapping successfully prevented re-entry in all cases (9 of 9). Overall, virtual ablation required 15-fold fewer ablation sites (235.5 ± 97.4 vs 17 ± 6.8) and 2-fold less ablation volume (5.34 ± 1.79 mL vs 2.11 ± 0.65 mL) than the clinical ablation. CONCLUSIONS RVI mapping allows localization of multiple regions susceptible to re-entry and may help guide VT ablation. RVI mapping does not require the induction of arrhythmia and may result in less ablated myocardial volumes with fewer ablation sites.
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11
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Zeppenfeld K, Tfelt-Hansen J, de Riva M, Winkel BG, Behr ER, Blom NA, Charron P, Corrado D, Dagres N, de Chillou C, Eckardt L, Friede T, Haugaa KH, Hocini M, Lambiase PD, Marijon E, Merino JL, Peichl P, Priori SG, Reichlin T, Schulz-Menger J, Sticherling C, Tzeis S, Verstrael A, Volterrani M. 2022 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. Eur Heart J 2022; 43:3997-4126. [PMID: 36017572 DOI: 10.1093/eurheartj/ehac262] [Citation(s) in RCA: 915] [Impact Index Per Article: 457.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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12
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Callans DJ, Donahue JK. Repolarization Heterogeneity in Human Post-Infarct Ventricular Tachycardia. JACC Clin Electrophysiol 2022; 8:713-718. [PMID: 35738846 DOI: 10.1016/j.jacep.2022.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Slow conduction, caused by fibrosis between surviving myocytes and connexin remodeling, is an important prerequisite for post-infarction ventricular tachycardia (VT); however, slow conduction is present throughout the infarct whereas VT circuits are finite in number and discrete. In a porcine model of VT, re-entrant circuits occur at region of significant repolarization heterogeneity caused by up-regulation of potassium channel β-subunits KCNE3 (increasing repolarization current) and KCNE4 (decreasing repolarization current), causing heterogeneous action potential durations. OBJECTIVES This study was designed to determine whether re-entrant circuits in human post-infarction VT are associated with repolarization heterogeneity. METHODS In 6 patients, left ventricular mapping was performed during induced VT to identify sites within the VT circuit. Subsequently, unipolar mapping (3.5-mm tip ablation catheter) was performed to characterize activation-recovery intervals (ARIs), which are surrogates for local action potential durations, at sites documented within the VT circuit isthmus (IN) compared to sites within the infarct scar but outside of the VT circuit (OUT). RESULTS ARIs were significantly shorter in the IN compared with the OUT sites (420.2 ± 79.3 ms vs 462 ± 52.8 ms; P = 0.01). In all patients. sites that were associated with the circuit always had shorter ARI values than did those sampled from OUT regions. CONCLUSIONS VT circuit sites in human post-infarct VT are associated with repolarization heterogeneity, similar to what was previously reported in a porcine model. This suggests the possibility of a common mechanism between humans and the porcine model of post-infarct VT, and that development of ablation strategies or small molecule or genetic therapies to restore normal repolarization kinetics may be antiarrhythmic.
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Affiliation(s)
- David J Callans
- Cardiac Electrophysiology Section, Cardiovascular Medicine Division, Department of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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13
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Lambiase PD. Rediscovering Repolarization: Timing Is Everything. JACC Clin Electrophysiol 2022; 8:719-721. [PMID: 35738847 DOI: 10.1016/j.jacep.2022.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/08/2022] [Accepted: 04/08/2022] [Indexed: 11/27/2022]
Affiliation(s)
- Pier D Lambiase
- University College London Institute of Cardiovascular Science, Barts Heart Centre, London, United Kingdom.
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14
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Elliott MK, Strocchi M, Mehta VS, Wijesuriya N, Mannakkara NN, Jackson T, Pereira H, Behar JM, Bishop MJ, Niederer S, Rinaldi CA. Dispersion of repolarization increases with cardiac resynchronization therapy and is associated with left ventricular reverse remodeling. J Electrocardiol 2022; 72:120-127. [PMID: 35468456 PMCID: PMC10171825 DOI: 10.1016/j.jelectrocard.2022.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/07/2022] [Accepted: 04/08/2022] [Indexed: 12/20/2022]
Abstract
PURPOSE Cardiac resynchronization therapy (CRT) reduces ventricular activation times and electrical dyssynchrony, however the effect on repolarization is unclear. In this study, we sought to investigate the effect of CRT and left ventricular (LV) remodeling on dispersion of repolarization using electrocardiographic imaging (ECGi). METHODS 11 patients with heart failure and electrical dyssynchrony underwent ECGi 1-day and 6-months post CRT. Reconstructed epicardial electrograms were used to create maps of activation time, repolarization time (RT) and activation recovery intervals (ARI) and calculate measures of RT, ARI and their dispersion. ARI was corrected for heart rate (cARI). RESULTS Compared to baseline rhythm, LV cARI dispersion was significantly higher at 6 months (28.2 ± 7.7 vs 36.4 ± 7.2 ms; P = 0.03) but not after 1 day (28.2 ± 7.7 vs 34.4 ± 6.8 ms; P = 0.12). There were no significant differences from baseline to CRT for mean LV cARI or RT metrics. Significant LV remodeling (>15% reduction in end-systolic volume) was an independent predictor of increase in LV cARI dispersion (P = 0.04) and there was a moderate correlation between the degree of LV remodeling and the relative increase in LV cARI dispersion (R = -0.49) though this was not statistically significant (P = 0.12). CONCLUSION CRT increases LV cARI dispersion, but this change was not fully apparent until 6 months post implant. The effects of CRT on LV cARI dispersion appeared to be dependent on LV reverse remodeling, which is in keeping with evidence that the risk of ventricular arrhythmia after CRT is higher in non-responders compared to responders.
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Affiliation(s)
- Mark K Elliott
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
| | - Marina Strocchi
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Vishal S Mehta
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Nadeev Wijesuriya
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Nilanka N Mannakkara
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Tom Jackson
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Helder Pereira
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Jonathan M Behar
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK
| | - Christopher A Rinaldi
- School of Biomedical Engineering and Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
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15
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Graham AJ, Orini M, Zacur E, Dhillon G, Jones D, Prabhu S, Pugliese F, Lowe M, Ahsan S, Earley MJ, Chow A, Sporton S, Dhinoja M, Hunter RJ, Schilling RJ, Lambiase PD. Assessing Noninvasive Delineation of Low-Voltage Zones Using ECG Imaging in Patients With Structural Heart Disease. JACC Clin Electrophysiol 2022; 8:426-436. [PMID: 35450597 DOI: 10.1016/j.jacep.2021.11.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 11/12/2021] [Accepted: 11/16/2021] [Indexed: 11/16/2022]
Abstract
OBJECTIVES This study sought to assess the association between electrocardiographic imaging (ECGI) parameters and voltage from simultaneous electroanatomic mapping (EAM). BACKGROUND ECGI offers noninvasive assessment of electrophysiologic features relevant for mapping ventricular arrhythmia and its substrate, but the accuracy of ECGI in the delineation of scar is unclear. METHODS Sixteen patients with structural heart disease underwent simultaneous ECGI (CardioInsight, Medtronic) and contact EAM (CARTO, Biosense-Webster) during ventricular tachycardia catheter ablation, with 7 mapped epicardially. ECGI and EAM geometries were coregistered using anatomic landmarks. ECGI points were paired to the closest site on the EAM within 10 mm. The association between EAM voltage and ECGI features from reconstructed epicardial unipolar electrograms was assessed by mixed-effects regression models. The classification of low-voltage regions was performed using receiver-operating characteristic analysis. RESULTS A total of 9,541 ECGI points (median: 596; interquartile range: 377-737 across patients) were paired to an EAM site. Epicardial EAM voltage was associated with ECGI features of signal fractionation and local repolarization dispersion (N = 7; P < 0.05), but they poorly classified sites with bipolar voltage of <1.5 mV or <0.5 mV thresholds (median area under the curve across patients: 0.50-0.62). No association was found between bipolar EAM voltage and low-amplitude reconstructed epicardial unipolar electrograms or ECGI-derived bipolar electrograms. Similar results were found in the combined cohort (n = 16), including endocardial EAM voltage compared to epicardial ECGI features (n = 9). CONCLUSIONS Despite a statistically significant association between ECGI features and EAM voltage, the accuracy of the delineation of low-voltage zones was modest. This may limit ECGI use for pr-procedural substrate analysis in ventricular tachycardia ablation, but it could provide value in risk assessment for ventricular arrhythmias.
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Affiliation(s)
- Adam J Graham
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Michele Orini
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom; Institute of Cardiovascular Science, University College London, London, United Kingdom
| | - Ernesto Zacur
- Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
| | - Gurpreet Dhillon
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Daniel Jones
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Sandeep Prabhu
- Department of Cardiology, The Alfred Hospital, Melbourne, Australia
| | - Francesca Pugliese
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Martin Lowe
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Syed Ahsan
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Mark J Earley
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Anthony Chow
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Simon Sporton
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Mehul Dhinoja
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Ross J Hunter
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Richard J Schilling
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom
| | - Pier D Lambiase
- Barts Heart Centre, Barts Health National Health Service Trust, London, United Kingdom; Institute of Cardiovascular Science, University College London, London, United Kingdom.
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16
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Elliott MK, Costa CM, Whitaker J, Gemmell P, Mehta VS, Sidhu BS, Gould J, Williams SE, O'Neill M, Razavi R, Niederer S, Bishop MJ, Rinaldi CA. Effect of scar and pacing location on repolarization in a porcine myocardial infarction model. Heart Rhythm O2 2022; 3:186-195. [PMID: 35496454 PMCID: PMC9043407 DOI: 10.1016/j.hroo.2022.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Background The effect of chronic ischemic scar on repolarization is unclear, with conflicting results from human and animal studies. An improved understanding of electrical remodeling within scar and border zone tissue may enhance substrate-guided ablation techniques for treatment of ventricular tachycardia. Computational modeling studies have suggested increased dispersion of repolarization during epicardial, but not endocardial, left ventricular pacing, in close proximity to scar. However, the effect of endocardial pacing near scar in vivo is unknown. Objective The purpose of this study was to investigate the effect of scar and pacing location on local repolarization in a porcine myocardial infarction model. Methods Six model pigs underwent late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging followed by electroanatomic mapping of the left ventricular endocardium. LGE-CMR images were registered to the anatomic shell and scar defined by LGE. Activation recovery intervals (ARIs), a surrogate for action potential duration, and local ARI gradients were calculated from unipolar electrograms within areas of late gadolinium enhancement (aLGE) and healthy myocardium. Results There was no significant difference between aLGE and healthy myocardium in mean ARI (304.20 ± 19.44 ms vs 300.59 ± 19.22 ms; P = .43), ARI heterogeneity (23.32 ± 11.43 ms vs 24.85 ± 12.99 ms; P = .54), or ARI gradients (6.18 ± 2.09 vs 5.66 ± 2.32 ms/mm; P = .39). Endocardial pacing distance from scar did not affect ARI gradients. Conclusion Our findings suggest that changes in ARI are not an intrinsic property of surviving myocytes within scar, and endocardial pacing close to scar does not affect local repolarization.
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Affiliation(s)
- Mark K Elliott
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Caroline Mendonca Costa
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Philip Gemmell
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Vishal S Mehta
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Baldeep S Sidhu
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Justin Gould
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Steven E Williams
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Steven Niederer
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Christopher A Rinaldi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
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17
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Mendonca Costa C, Gemmell P, Elliott MK, Whitaker J, Campos FO, Strocchi M, Neic A, Gillette K, Vigmond E, Plank G, Razavi R, O'Neill M, Rinaldi CA, Bishop MJ. Determining anatomical and electrophysiological detail requirements for computational ventricular models of porcine myocardial infarction. Comput Biol Med 2022; 141:105061. [PMID: 34915331 PMCID: PMC8819160 DOI: 10.1016/j.compbiomed.2021.105061] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/04/2021] [Accepted: 11/20/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND Computational models of the heart built from cardiac MRI and electrophysiology (EP) data have shown promise for predicting the risk of and ablation targets for myocardial infarction (MI) related ventricular tachycardia (VT), as well as to predict paced activation sequences in heart failure patients. However, most recent studies have relied on low resolution imaging data and little or no EP personalisation, which may affect the accuracy of model-based predictions. OBJECTIVE To investigate the impact of model anatomy, MI scar morphology, and EP personalisation strategies on paced activation sequences and VT inducibility to determine the level of detail required to make accurate model-based predictions. METHODS Imaging and EP data were acquired from a cohort of six pigs with experimentally induced MI. Computational models of ventricular anatomy, incorporating MI scar, were constructed including bi-ventricular or left ventricular (LV) only anatomy, and MI scar morphology with varying detail. Tissue conductivities and action potential duration (APD) were fitted to 12-lead ECG data using the QRS duration and the QT interval, respectively, in addition to corresponding literature parameters. Paced activation sequences and VT induction were simulated. Simulated paced activation and VT inducibility were compared between models and against experimental data. RESULTS Simulations predict that the level of model anatomical detail has little effect on simulated paced activation, with all model predictions comparing closely with invasive EP measurements. However, detailed scar morphology from high-resolution images, bi-ventricular anatomy, and personalized tissue conductivities are required to predict experimental VT outcome. CONCLUSION This study provides clear guidance for model generation based on clinical data. While a representing high level of anatomical and scar detail will require high-resolution image acquisition, EP personalisation based on 12-lead ECG can be readily incorporated into modelling pipelines, as such data is widely available.
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Affiliation(s)
- Caroline Mendonca Costa
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK.
| | - Philip Gemmell
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | - Mark K Elliott
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | - John Whitaker
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | - Fernando O Campos
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | - Marina Strocchi
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | | | - Karli Gillette
- Gottfried Schatz Research Center, Biophysics, Medical University of Graz, Austria; Medical University of Graz, Austria and BioTechMed, Graz, Austria
| | - Edward Vigmond
- Institut de Rythmologie et de modélisation cardiaque (LIRYC), University of Bordeaux, France
| | - Gernot Plank
- Medical University of Graz, Austria and BioTechMed, Graz, Austria
| | - Reza Razavi
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
| | - Mark O'Neill
- Department of Cardiology, Guy's and St Thomas' Hospital, London, UK
| | - Christopher A Rinaldi
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK; Department of Cardiology, Guy's and St Thomas' Hospital, London, UK
| | - Martin J Bishop
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, UK
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18
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Halfar R, Lawson BAJ, dos Santos RW, Burrage K. Machine Learning Identification of Pro-arrhythmic Structures in Cardiac Fibrosis. Front Physiol 2021; 12:709485. [PMID: 34483962 PMCID: PMC8415115 DOI: 10.3389/fphys.2021.709485] [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: 05/14/2021] [Accepted: 06/30/2021] [Indexed: 12/17/2022] Open
Abstract
Cardiac fibrosis and other scarring of the heart, arising from conditions ranging from myocardial infarction to ageing, promotes dangerous arrhythmias by blocking the healthy propagation of cardiac excitation. Owing to the complexity of the dynamics of electrical signalling in the heart, however, the connection between different arrangements of blockage and various arrhythmic consequences remains poorly understood. Where a mechanism defies traditional understanding, machine learning can be invaluable for enabling accurate prediction of quantities of interest (measures of arrhythmic risk) in terms of predictor variables (such as the arrangement or pattern of obstructive scarring). In this study, we simulate the propagation of the action potential (AP) in tissue affected by fibrotic changes and hence detect sites that initiate re-entrant activation patterns. By separately considering multiple different stimulus regimes, we directly observe and quantify the sensitivity of re-entry formation to activation sequence in the fibrotic region. Then, by extracting the fibrotic structures around locations that both do and do not initiate re-entries, we use neural networks to determine to what extent re-entry initiation is predictable, and over what spatial scale conduction heterogeneities appear to act to produce this effect. We find that structural information within about 0.5 mm of a given point is sufficient to predict structures that initiate re-entry with more than 90% accuracy.
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Affiliation(s)
- Radek Halfar
- IT4Innovations, VSB-Technical University of Ostrava, Ostrava, Czechia
| | - Brodie A. J. Lawson
- Centre for Data Science, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Rodrigo Weber dos Santos
- Graduate Program in Computational Modeling, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Kevin Burrage
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
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19
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Srinivasan NT, Garcia J, Schilling RJ, Ahsan S, Hunter RJ, Lowe M, Chow AW, Lambiase PD. Dynamic spatial dispersion of repolarization is present in regions critical for ischemic ventricular tachycardia ablation. Heart Rhythm O2 2021; 2:280-289. [PMID: 34337579 PMCID: PMC8322930 DOI: 10.1016/j.hroo.2021.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The presence of dynamic substrate changes may facilitate functional block and reentry in ventricular tachycardia (VT). OBJECTIVE We aimed to study dynamic ventricular repolarization changes in critical regions of the VT circuit during sensed single extrastimulus pacing known as the Sense Protocol (SP). METHODS Twenty patients (aged 67 ± 9 years, 17 male) underwent VT ablation. A bipolar voltage map was obtained during sinus rhythm (SR) and right ventricular SP pacing at 20 ms above ventricular effective refractory period. Ventricular repolarization maps were constructed. Ventricular repolarization time (RT) was calculated from unipolar electrogram T waves, using the Wyatt method, as the dV/dtmax of the unipolar T wave. Entrainment or pace mapping confirmed critical sites for ablation. RESULTS The median global repolarization range (max-min RT per patient) was 166 ms (interquartile range [IQR] 143-181 ms) during SR mapping vs 208 ms (IQR 182-234) during SP mapping (P = .0003 vs intrinsic rhythm). Regions of late potentials (LP) had a longer RT during SP mapping compared to regions without LP (mean 394 ± 40 ms vs 342 ± 25 ms, P < .001). In paired regions of normal myocardium there was no significant spatial dispersion of repolarization (SDR)/10 mm2 during SP mapping vs SR mapping (SDR 11 ± 6 ms vs 10 ± 6 ms, P = .54). SDR/10 mm2 was greater in critical areas of the VT circuit during SP mapping 63 ± 29 ms vs SR mapping 16 ± 9 ms (P < .001). CONCLUSION Ventricular repolarization is prolonged in regions of LP and increases dynamically, resulting in dynamic SDR in critical areas of the VT circuit. These dynamic substrate changes may be an important factor that facilitates VT circuits.
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Affiliation(s)
- Neil T. Srinivasan
- Department of Cardiac Electrophysiology, The Essex Cardiothoracic Centre, Basildon, Essex, United Kingdom
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
- Institute of Cardiovascular Science, University College London, London, United Kingdom
- Circulatory Health Research Group, Medical Technology Research Centre, School of Medicine, Anglia Ruskin University, Essex, United Kingdom
| | - Jason Garcia
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Richard J. Schilling
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Syed Ahsan
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Ross J. Hunter
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Martin Lowe
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Anthony W. Chow
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
| | - Pier D. Lambiase
- Department of Cardiac Electrophysiology, The Barts Heart Center, St Bartholomew’s Hospital, London, United Kingdom
- Institute of Cardiovascular Science, University College London, London, United Kingdom
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20
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Young WJ, van Duijvenboden S, Ramírez J, Jones A, Tinker A, Munroe PB, Lambiase PD, Orini M. A Method to Minimise the Impact of ECG Marker Inaccuracies on the Spatial QRS-T angle: Evaluation on 1,512 Manually Annotated ECGs. Biomed Signal Process Control 2021; 64:102305. [PMID: 33537064 PMCID: PMC7762839 DOI: 10.1016/j.bspc.2020.102305] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inaccuracies of QRS and T-wave markers significantly impact QRS-Ta estimation. These errors influence the classification of clinically relevant abnormal values. Our algorithm provides robust measurements in the presence of inaccurate VCG markers. We present for the first time, the distribution of the QRS-Ta in a large cohort.
The spatial QRS-T angle (QRS-Ta) derived from the vectorcardiogram (VCG) is a strong risk predictor for ventricular arrhythmia and sudden cardiac death with potential use for mass screening. Accurate QRS-Ta estimation in the presence of ECG delineation errors is crucial for its deployment as a prognostic test. Our study assessed the effect of inaccurate QRS and T-wave marker placement on QRS-Ta estimation and proposes a robust method for its calculation. Reference QRS-Ta measurements were derived from 1,512 VCGs manually annotated by three expert reviewers. We systematically changed onset and offset timings of QRS and T-wave markers to simulate inaccurate placement. The QRS-Ta was recalculated using a standard approach and our proposed algorithm, which limits the impact of VCG marker inaccuracies by defining the vector origin as an interval preceding QRS-onset and redefines the beginning and end of QRS and T-wave loops. Using the standard approach, mean absolute errors (MAE) in peak QRS-Ta were >40% and sensitivity and precision in the detection of abnormality (>105°) were <80% and <65% respectively, when QRS-onset was delayed or QRS-offset anticipated >15 ms. Using our proposed algorithm, MAE for peak QRS-Ta were reduced to <4% and sensitivity and precision of abnormality were >94% for inaccuracies up to ±15 ms. Similar results were obtained for mean QRS-Ta. In conclusion, inaccuracies of QRS and T-wave markers can significantly influence the QRS-Ta. Our proposed algorithm provides robust QRS-Ta measurements in the presence of inaccurate VCG annotation, enabling its use in large datasets.
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Affiliation(s)
- William J Young
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom.,Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS trust, London, EC1A 7BE, United Kingdom
| | - Stefan van Duijvenboden
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom.,Institute of Cardiovascular Sciences, University of College London, WC1E 6BT, United Kingdom
| | - Julia Ramírez
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom.,Institute of Cardiovascular Sciences, University of College London, WC1E 6BT, United Kingdom
| | - Aled Jones
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom
| | - Andrew Tinker
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom
| | - Patricia B Munroe
- Clinical Pharmacology Department, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ, United Kingdom
| | - Pier D Lambiase
- Institute of Cardiovascular Sciences, University of College London, WC1E 6BT, United Kingdom.,Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS trust, London, EC1A 7BE, United Kingdom
| | - Michele Orini
- Institute of Cardiovascular Sciences, University of College London, WC1E 6BT, United Kingdom.,Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS trust, London, EC1A 7BE, United Kingdom
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21
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Dynamic high-density functional substrate mapping to treat ventricular tachycardia-Time for electrophysiology to come home. Heart Rhythm 2021; 18:732-733. [PMID: 33482384 DOI: 10.1016/j.hrthm.2021.01.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 01/12/2021] [Indexed: 11/23/2022]
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22
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Campos FO, Orini M, Arnold R, Whitaker J, O'Neill M, Razavi R, Plank G, Hanson B, Porter B, Rinaldi CA, Gill J, Lambiase PD, Taggart P, Bishop MJ. Assessing the ability of substrate mapping techniques to guide ventricular tachycardia ablation using computational modelling. Comput Biol Med 2021; 130:104214. [PMID: 33476992 DOI: 10.1016/j.compbiomed.2021.104214] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 01/05/2021] [Accepted: 01/05/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Identification of targets for ablation of post-infarction ventricular tachycardias (VTs) remains challenging, often requiring arrhythmia induction to delineate the reentrant circuit. This carries a risk for the patient and may not be feasible. Substrate mapping has emerged as a safer strategy to uncover arrhythmogenic regions. However, VT recurrence remains common. GOAL To use computer simulations to assess the ability of different substrate mapping approaches to identify VT exit sites. METHODS A 3D computational model of the porcine post-infarction heart was constructed to simulate VT and paced rhythm. Electroanatomical maps were constructed based on endocardial electrogram features and the reentry vulnerability index (RVI - a metric combining activation (AT) and repolarization timings to identify tissue susceptibility to reentry). Since scar transmurality in our model was not homogeneous, parameters derived from all signals (including dense scar regions) were used in the analysis. Potential ablation targets obtained from each electroanatomical map during pacing were compared to the exit site detected during VT mapping. RESULTS Simulation data showed that voltage cut-offs applied to bipolar electrograms could delineate the scar, but not the VT circuit. Electrogram fractionation had the highest correlation with scar transmurality. The RVI identified regions closest to VT exit site but was outperformed by AT gradients combined with voltage cut-offs. The performance of all metrics was affected by pacing location. CONCLUSIONS Substrate mapping could provide information about the infarct, but the directional dependency on activation should be considered. Activation-repolarization metrics have utility in safely identifying VT targets, even with non-transmural scars.
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Affiliation(s)
- Fernando O Campos
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom.
| | - Michele Orini
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Electrophysiology Department, Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - Robert Arnold
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging), Division of Biophysics, Graz, Austria
| | - John Whitaker
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - Reza Razavi
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
| | - Gernot Plank
- Gottfried Schatz Research Center (for Cell Signaling, Metabolism and Aging), Division of Biophysics, Graz, Austria
| | - Ben Hanson
- Department of Mechanical Engineering, University College London, London, United Kingdom
| | - Bradley Porter
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom; Department of Cardiology, Guys and St Thomas' NHS Trust, London, United Kingdom
| | | | - Jaswinder Gill
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom; Department of Cardiology, Guys and St Thomas' NHS Trust, London, United Kingdom
| | - Pier D Lambiase
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Electrophysiology Department, Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - Peter Taggart
- Institute of Cardiovascular Science, University College London, London, United Kingdom; Electrophysiology Department, Barts Heart Centre, St Bartholomew's Hospital, London, United Kingdom
| | - Martin J Bishop
- School of Biomedical Engineering and Imaging Sciences, Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, United Kingdom
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23
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Proietti R, Dowd R, Gee LV, Yusuf S, Panikker S, Hayat S, Osman F, Patel K, Salim H, Aldhoon B, Foster W, Merghani A, Kuehl M, Banerjee P, Lellouche N, Dhanjal T. Impact of a high-density grid catheter on long-term outcomes for structural heart disease ventricular tachycardia ablation. J Interv Card Electrophysiol 2021; 62:519-529. [PMID: 33392856 PMCID: PMC8645535 DOI: 10.1007/s10840-020-00918-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/31/2020] [Indexed: 01/04/2023]
Abstract
Background Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia (VT) ablation. State-of-the-art multipolar mapping catheters have enhanced mapping capabilities. The purpose of this study was to investigate whether long-term outcomes were improved with the use of a HD Grid mapping catheter combining complementary mapping strategies in patients with structural heart disease VT. Methods Consecutive patients underwent VT ablation assigned to either HD Grid, Pentaray, Duodeca, or point-by-point (PbyP) RF mapping catheters. Clinical endpoints included recurrent anti-tachycardia pacing (ATP), appropriate shock, asymptomatic non-sustained VT, or all-cause death. Results Seventy-three procedures were performed (33 HD Grid, 22 Pentaray, 12 Duodeca, and 6 PbyP) with no significant difference in baseline characteristics. Substrate mapping was performed in 97% of cases. Activation maps were generated in 82% of HD Grid cases (Pentaray 64%; Duodeca 92%; PbyP 33% (p = 0.025)) with similar trends in entrainment and pace mapping. Elimination of all VTs occurred in 79% of HD Grid cases (Pentaray 55%; Duodeca 83%; PbyP 33% (p = 0.04)). With a mean follow-up of 372 ± 234 days, freedom from recurrent ATP and shock was 97% and 100% respectively in the HD Grid group (Pentaray 64%, 82%; Duodeca 58%, 83%; PbyP 33%, 33% (log rank p = 0.0042, p = 0.0002)). Conclusions This study highlights a step-wise improvement in survival free from ICD therapies as the density of mapping capability increases. By using a high-density mapping catheter and combining complementary mapping strategies in a strict procedural workflow, long-term clinical outcomes are improved.
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Affiliation(s)
- Riccardo Proietti
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK.,Department of Cardiac, Thoracic, Vascular Sciences, and University of Padua, Padua, Italy
| | - Rory Dowd
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Lim Ven Gee
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Shamil Yusuf
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Sandeep Panikker
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Sajad Hayat
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Faizel Osman
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK.,University of Warwick (Medical School), Gibbet Hill, Coventry, CV4 7AJ, UK
| | - Kiran Patel
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK.,University of Warwick (Medical School), Gibbet Hill, Coventry, CV4 7AJ, UK
| | - Handi Salim
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Bashar Aldhoon
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Will Foster
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Ahmed Merghani
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Michael Kuehl
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Prithwish Banerjee
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK
| | - Nicolas Lellouche
- Hopital Henri Mondor Albert Chenevier, University Paris Est Creteil Paris XII, Avenue du Marechal de Lattre de Tassigny, 94000, Creteil, Inserm U955, Paris, France
| | - Tarvinder Dhanjal
- Department of Cardiology, University Hospital Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX, UK. .,University of Warwick (Medical School), Gibbet Hill, Coventry, CV4 7AJ, UK.
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24
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Crinion D, Neira V, Al Hamad N, de Leon A, Bakker D, Korogyi A, Abdollah H, Glover B, Simpson C, Baranchuk A, Chacko S, Enriquez A, Redfearn D. Close-coupled pacing to identify the "functional" substrate of ventricular tachycardia: Long-term outcomes of the paced electrogram feature analysis technique. Heart Rhythm 2020; 18:723-731. [PMID: 33378703 DOI: 10.1016/j.hrthm.2020.12.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 12/09/2020] [Accepted: 12/22/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND The conduction delay and block that compose the critical isthmus of macroreentrant ventricular tachycardia (VT) is partly "functional" in that they only occur at faster cycle lengths. Close-coupled pacing stresses the myocardium's conduction capacity and may reveal late potentials (LPs) and fractionation. Interest has emerged in targeting this functional substrate. OBJECTIVE The purpose of this study was to assess the feasibility and efficacy of a functional substrate VT ablation strategy. METHODS Patients with scar-related VT undergoing their first ablation were recruited. A closely coupled extrastimulus (ventricular effective refractory period + 30 ms) was delivered at the right ventricular apex while mapping with a high-density catheter. Sites of functional impaired conduction exhibited increased electrogram duration due to LPs/fractionation. The time to last deflection was annotated on an electroanatomic map, readily identifying ablation targets. RESULTS A total of 40 patients were recruited (34 [85%] ischemic). Median procedure duration was 330 minutes (interquartile range [IQR] 300-369), and ablation time was 49.4 minutes (IQR 33.8-48.3). Median functional substrate area was 41.9 cm2 (IQR 22.1-73.9). It was similarly distributed across bipolar voltage zones. Noninducibility was achieved in 34 of 40 patients (85%). Median follow-up was 711 days (IQR 255.5-972.8), during which 35 of 39 patients (89.7%) did not have VT recurrence, and 3 of 39 (7.5%) died. Antiarrhythmic drugs were continued in 53.8% (21/39). CONCLUSION Functional substrate ablation resulted in high rates of noninducibility and freedom from VT. Mapping times were increased considerably. Our findings add to the encouraging trend reported by related techniques. Randomized multicenter trials are warranted to assess this next phase of VT ablation.
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Affiliation(s)
- Derek Crinion
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Victor Neira
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Nasser Al Hamad
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Ana de Leon
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - David Bakker
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | | | - Hoshiar Abdollah
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Ben Glover
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Christopher Simpson
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Adrian Baranchuk
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Sanoj Chacko
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Andres Enriquez
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada
| | - Damian Redfearn
- Heart Rhythm Service, Queen's University, Kingston Health Sciences, Ontario, Canada.
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