1
|
Tonko JB, Lozano C, Moreno J, Chow A, Dhinoja M, Lambiase PD. Near-field detection and peak frequency metric for substrate and activation mapping of ventricular tachycardias in two- and three-dimensional circuits. Europace 2024; 26:euae154. [PMID: 38833626 PMCID: PMC11259853 DOI: 10.1093/europace/euae154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 05/31/2024] [Indexed: 06/06/2024] Open
Abstract
AIMS Successful ventricular arrhythmia (VA) ablation requires identification of functionally critical sites during contact mapping. Estimation of the peak frequency (PF) component of the electrogram (EGM) may improve correct near-field (NF) annotation to identify circuit segments on the mapped surface. In turn, assessment of NF and far-field (FF) EGMs may delineate the three-dimensional path of a ventricular tachycardia (VT) circuit. METHODS AND RESULTS A proprietary NF detection algorithm was applied retrospectively to scar-related re-entry VT maps and compared with manually reviewed maps employing first deflection (FDcorr) for VT activation maps and last deflection (LD) for substrate maps. Ventricular tachycardia isthmus location and characteristics mapped with FDcorr vs. NF were compared. Omnipolar low-voltage areas, late activating areas, and deceleration zones (DZ) in LD vs. NF substrate maps were compared. On substrate maps, PF estimation was compared between isthmus and bystander sites. Activation mapping with entrainment and/or VT termination with radiofrequency (RF) ablation confirmed critical sites. Eighteen patients with high-density VT activation and substrate maps (55.6% ischaemic) were included. Near-field detection correctly located critical parts of the circuit in 77.7% of the cases compared with manually reviewed VT maps as reference. In substrate maps, NF detection identified deceleration zones in 88.8% of cases, which overlapped with FDcorr VT isthmus in 72.2% compared with 83.3% overlap of DZ assessed by LD. Applied to substrate maps, PF as a stand-alone feature did not differentiate VT isthmus sites from low-voltage bystander sites. Omnipolar voltage was significantly higher at isthmus sites with longer EGM durations compared with low-voltage bystander sites. CONCLUSION The NF algorithm may enable rapid high-density activation mapping of VT circuits in the NF of the mapped surface. Integrated assessment and combined analysis of NF and FF EGM-components could support characterization of three-dimensional VT circuits with intramural segments. For scar-related substrate mapping, PF as a stand-alone EGM feature did not enable the differentiation of functionally critical sites of the dominant VT from low-voltage bystander sites in this cohort.
Collapse
Affiliation(s)
- Johanna B Tonko
- Institute for Cardiovascular Science, University College London, 5 University Street, London, WC1E 6JF, UK
- Barts Heart Centre, St Bartholomew s Hospital, W Smithfield, London EC1A 7BE, UK
| | - Cristina Lozano
- Department of Cardiology, Hospital Universitario Ramón Y Cajal, Colmenar Viejo road, km. 9,100, Madrid 28034, Spain
| | - Javier Moreno
- Department of Cardiology, Hospital Universitario Ramón Y Cajal, Colmenar Viejo road, km. 9,100, Madrid 28034, Spain
| | - Anthony Chow
- Barts Heart Centre, St Bartholomew s Hospital, W Smithfield, London EC1A 7BE, UK
| | - Mehul Dhinoja
- Barts Heart Centre, St Bartholomew s Hospital, W Smithfield, London EC1A 7BE, UK
| | - Pier D Lambiase
- Institute for Cardiovascular Science, University College London, 5 University Street, London, WC1E 6JF, UK
- Barts Heart Centre, St Bartholomew s Hospital, W Smithfield, London EC1A 7BE, UK
| |
Collapse
|
2
|
Willems E, Janssens KLPM, Dekker LRC, van de Vosse FN, Cluitmans MJM, Bovendeerd PHM. Strain-controlled electrophysiological wave propagation alters in silico scar-based substrate for ventricular tachycardia. Front Physiol 2024; 15:1330157. [PMID: 38655031 PMCID: PMC11036413 DOI: 10.3389/fphys.2024.1330157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 03/21/2024] [Indexed: 04/26/2024] Open
Abstract
Introduction: Assessing a patient's risk of scar-based ventricular tachycardia (VT) after myocardial infarction is a challenging task. It can take months to years after infarction for VT to occur. Also, if selected for ablation therapy, success rates are low. Methods: Computational ventricular models have been presented previously to support VT risk assessment and to provide ablation guidance. In this study, an extension to such virtual-heart models is proposed to phenomenologically incorporate tissue remodeling driven by mechanical load. Strain amplitudes in the heart muscle are obtained from simulations of mechanics and are used to adjust the electrical conductivity. Results: The mechanics-driven adaptation of electrophysiology resulted in a more heterogeneous distribution of propagation velocities than that of standard models, which adapt electrophysiology in the structural substrate from medical images only. Moreover, conduction slowing was not only present in such a structural substrate, but extended in the adjacent functional border zone with impaired mechanics. This enlarged the volumes with high repolarization time gradients (≥10 ms/mm). However, maximum gradient values were not significantly affected. The enlarged volumes were localized along the structural substrate border, which lengthened the line of conduction block. The prolonged reentry pathways together with conduction slowing in functional regions increased VT cycle time, such that VT was easier to induce, and the number of recommended ablation sites increased from 3 to 5 locations. Discussion: Sensitivity testing showed an accurate model of strain-dependency to be critical for low ranges of conductivity. The model extension with mechanics-driven tissue remodeling is a potential approach to capture the evolution of the functional substrate and may offer insight into the progression of VT risk over time.
Collapse
Affiliation(s)
- Evianne Willems
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Koen L. P. M. Janssens
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Lukas R. C. Dekker
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
- Department of Cardiology, Catharina Hospital, Eindhoven, Netherlands
| | - Frans N. van de Vosse
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Matthijs J. M. Cluitmans
- Maastricht University Medical Center, Maastricht, Netherlands
- Philips Research Eindhoven, Eindhoven, Netherlands
| | - Peter H. M. Bovendeerd
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands
| |
Collapse
|
3
|
Roukoz H, Tholakanahalli V. Epicardial ablation of ventricular tachycardia in ischemic cardiomyopathy: A review and local experience. Indian Pacing Electrophysiol J 2024; 24:84-93. [PMID: 38340957 PMCID: PMC11010455 DOI: 10.1016/j.ipej.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 10/29/2023] [Accepted: 02/07/2024] [Indexed: 02/12/2024] Open
Abstract
Myocardial scar in ischemic cardiomyopathy is predominantly endocardial, however, between 5% and 15% of these patients have an arrhythmogenic epicardial substrate. Percutaneous epicardial ablation should be considered in patients with ICM and VT especially if they failed an endocardial ablation. Simultaneous epicardial and endocardial ablation of VT in ICM may reduce short- and medium-term VT recurrence compared with an endocardial only approach. Cardiac imaging could be used to help guide patient selection for a combined epi-endo approach. Complications related to epicardial access can happen in up to 7% of patients. Epicardial ablation in these patients should be referred to experienced tertiary centers. We review the literature and share interesting cases.
Collapse
|
4
|
Iravanian S, Uzelac I, Shah AD, Toye MJ, Lloyd MS, Burke MA, Daneshmand MA, Attia TS, Vega JD, El-Chami MF, Merchant FM, Cherry EM, Bhatia NK, Fenton FH. Complex repolarization dynamics in ex vivo human ventricles are independent of the restitution properties. Europace 2023; 25:euad350. [PMID: 38006390 PMCID: PMC10751849 DOI: 10.1093/europace/euad350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 11/13/2023] [Indexed: 11/27/2023] Open
Abstract
AIMS The mechanisms of transition from regular rhythms to ventricular fibrillation (VF) are poorly understood. The concordant to discordant repolarization alternans pathway is extensively studied; however, despite its theoretical centrality, cannot guide ablation. We hypothesize that complex repolarization dynamics, i.e. oscillations in the repolarization phase of action potentials with periods over two of classic alternans, is a marker of electrically unstable substrate, and ablation of these areas has a stabilizing effect and may reduce the risk of VF. To prove the existence of higher-order periodicities in human hearts. METHODS AND RESULTS We performed optical mapping of explanted human hearts obtained from recipients of heart transplantation at the time of surgery. Signals recorded from the right ventricle endocardial surface were processed to detect global and local repolarization dynamics during rapid pacing. A statistically significant global 1:4 peak was seen in three of six hearts. Local (pixel-wise) analysis revealed the spatially heterogeneous distribution of Periods 4, 6, and 8, with the regional presence of periods greater than two in all the hearts. There was no significant correlation between the underlying restitution properties and the period of each pixel. CONCLUSION We present evidence of complex higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex vivo human hearts. We infer that the oscillation of the calcium cycling machinery is the primary mechanism of higher-order dynamics. These higher-order regions may act as niduses of instability and may provide targets for substrate-based ablation of VF.
Collapse
Affiliation(s)
- Shahriar Iravanian
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Ilija Uzelac
- Georgia Institute of Technology, Department of Physics, 837 State St NW, Atlanta, GA 30332, USA
| | - Anand D Shah
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Mikael J Toye
- Georgia Institute of Technology, Department of Physics, 837 State St NW, Atlanta, GA 30332, USA
| | - Michael S Lloyd
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Michael A Burke
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Mani A Daneshmand
- Department of Surgery, Division of Cardiovascular Surgery, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Tamer S Attia
- Department of Surgery, Division of Cardiovascular Surgery, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - John David Vega
- Department of Surgery, Division of Cardiovascular Surgery, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Mikhael F El-Chami
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Faisal M Merchant
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Elizabeth M Cherry
- Georgia Institute of Technology, Department of Physics, 837 State St NW, Atlanta, GA 30332, USA
| | - Neal K Bhatia
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, 1364 Clifton Road, Atlanta, GA 30322, USA
| | - Flavio H Fenton
- Georgia Institute of Technology, Department of Physics, 837 State St NW, Atlanta, GA 30332, USA
| |
Collapse
|
5
|
Cedilnik N, Pop M, Duchateau J, Sacher F, Jaïs P, Cochet H, Sermesant M. Efficient Patient-Specific Simulations of Ventricular Tachycardia Based on Computed Tomography-Defined Wall Thickness Heterogeneity. JACC Clin Electrophysiol 2023; 9:2507-2519. [PMID: 37804259 DOI: 10.1016/j.jacep.2023.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 07/20/2023] [Accepted: 08/02/2023] [Indexed: 10/09/2023]
Abstract
BACKGROUND Electrophysiological mapping of ventricular tachycardia (VT) is tedious and poorly reproducible. Substrate analysis on imaging cannot explicitly display VT circuits. OBJECTIVES This study sought to introduce a computed tomography-based model personalization approach, allowing for the simulation of postinfarction VT in a clinically compatible time frame. METHODS In 10 patients (age 65 ± 11 years, 9 male) referred for post-VT ablation, computed tomography-derived wall thickness maps were registered to 25 electroanatomical maps (sinus rhythm, paced, and VT). The relationship between wall thickness and electrophysiological characteristics (activation-recovery interval) was analyzed. Wall thickness was then employed to parameterize a fast and tractable organ-scale wave propagation model. Pacing protocols were simulated from multiple sites to test VT induction in silico. In silico VTs were compared to VT circuits mapped clinically. RESULTS Clinically, 6 different VTs could be induced with detailed maps in 9 patients. The proposed model allowed for fast simulation (median: 6 min/pacing site). Simulations of steady pacing (600 milliseconds) from 100 different sites/patient never triggered any arrhythmia. Applying S1-S2 or S1-S2-S3 induction schemes allowed for the induction of in silico VTs in the 9 of 10 patients who were clinically inducible. The patient who was not inducible clinically was also noninducible in silico. A total of 42 different VTs were simulated (4.2 ± 2 per patient). Six in silico VTs matched a VT circuit mapped clinically. CONCLUSIONS The proposed framework allows for personalized simulations in a matter of hours. In 6 of 9 patients, simulations show re-entrant patterns matching intracardiac recordings.
Collapse
Affiliation(s)
- Nicolas Cedilnik
- Université Côte d'Azur, Epione, Inria, Sophia-Antipolis, France; Institut Hospitalo-Universitaire Liryc, Bordeaux, France.
| | - Mihaela Pop
- Université Côte d'Azur, Epione, Inria, Sophia-Antipolis, France
| | - Josselin Duchateau
- Institut Hospitalo-Universitaire Liryc, Bordeaux, France; Cardiac Pacing and Electrophysiology Department, Bordeaux University Hospital, Bordeaux, France
| | - Frédéric Sacher
- Institut Hospitalo-Universitaire Liryc, Bordeaux, France; Cardiac Pacing and Electrophysiology Department, Bordeaux University Hospital, Bordeaux, France
| | - Pierre Jaïs
- Institut Hospitalo-Universitaire Liryc, Bordeaux, France; Cardiac Pacing and Electrophysiology Department, Bordeaux University Hospital, Bordeaux, France
| | - Hubert Cochet
- Institut Hospitalo-Universitaire Liryc, Bordeaux, France; Radiology Department, Bordeaux University Hospital, Bordeaux, France
| | - Maxime Sermesant
- Université Côte d'Azur, Epione, Inria, Sophia-Antipolis, France; Institut Hospitalo-Universitaire Liryc, Bordeaux, France
| |
Collapse
|
6
|
Elewa MG, Altoukhy S, Badran HA, El Damanhoury H, Zarif JK. Ablation targets of scar-related ventricular tachycardia identified by dynamic functional substrate mapping. Egypt Heart J 2023; 75:87. [PMID: 37831212 PMCID: PMC10575820 DOI: 10.1186/s43044-023-00414-w] [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: 07/10/2023] [Accepted: 10/03/2023] [Indexed: 10/14/2023] Open
Abstract
BACKGROUND Dynamic functional substrate mapping of scar-related ventricular tachycardia offers better identification of ablation targets with limited ablation lesions. Several functional substrate mapping approaches have been proposed, including decrement-evoked potential (DEEP) mapping. The aim of our study was to compare the short- and long-term efficacy of a DEEP-guided versus a fixed-substrate-guided strategy for the ablation of scar-related ventricular tachycardia (VT). RESULTS Forty consecutive patients presenting for ablation of scar-related VT were randomized to either DEEP-guided or substrate-guided ablation. Late potentials were tagged and ablated in the non-DEEP group, while those in the DEEP group were subjected to RV extrastimulation after a drive train. Only potentials showing significant delay were ablated. Patients were followed for a median duration of 12 months. Twenty patients were allocated to the DEEP group, while the other 20 were allocated to the non-DEEP group. Twelve patients (60%) in the DEEP group had ischemic cardiomyopathy versus 10 patients (50%) in the non-DEEP group (P-value 0.525). Intraoperatively, the median percentage of points with LPs was 19% in the DEEP group and 20.6% in the non-DEEP group. The procedural time was longer in the DEEP group, approaching but missing statistical significance (P-value 0.059). VT non-inducibility was successfully accomplished in 16 patients (80%) in the DEEP group versus 17 patients (85%) in the non-DEEP group (P value 0.597). After a median follow-up duration of 12 months, the VT recurrence rate was 65% in both groups (P value 0.311), with a dropout rate of 10% in the DEEP group. As for the secondary endpoints, all-cause mortality rates were 20% and 25% in the DEEP and non-DEEP groups, respectively (P-value 0.342). CONCLUSIONS DEEP-assisted ablation of scar-related ventricular tachycardia is a feasible strategy with comparable short- and long-term outcomes to a fixed-substrate-based strategy with more specific ablation targets, albeit relatively longer but non-significant procedural times and higher procedural deaths. The imbalance between the study groups in terms of epicardial versus endocardial mapping, although non-significant, warrants the prudent interpretation of our results. Further large-scale randomized trials are recommended. TRIAL REGISTRATION clinicaltrials.gov, registration number: NCT05086510, registered on 28th September 2021, record https://classic. CLINICALTRIALS gov/ct2/show/NCT05086510.
Collapse
Affiliation(s)
- Mohammad Gamal Elewa
- Cardiology Department, Ain Shams University Hospital, Faculty of Medicine, Ain Shams University, 5B - Swiss Project B, PO 11826, Nasr City, Cairo, Egypt.
| | - Sherif Altoukhy
- Cardiology Department, Ain Shams University Hospital, Faculty of Medicine, Ain Shams University, 5B - Swiss Project B, PO 11826, Nasr City, Cairo, Egypt
| | - Haitham Abdelfattah Badran
- Cardiology Department, Ain Shams University Hospital, Faculty of Medicine, Ain Shams University, 5B - Swiss Project B, PO 11826, Nasr City, Cairo, Egypt
| | - Hayam El Damanhoury
- Cardiology Department, Ain Shams University Hospital, Faculty of Medicine, Ain Shams University, 5B - Swiss Project B, PO 11826, Nasr City, Cairo, Egypt
| | - John Kamel Zarif
- Cardiology Department, Ain Shams University Hospital, Faculty of Medicine, Ain Shams University, 5B - Swiss Project B, PO 11826, Nasr City, Cairo, Egypt
| |
Collapse
|
7
|
Xu L, Zahid S, Khoshknab M, Moss J, Berger RD, Chrispin J, Callans D, Marchlinski FE, Zimmerman SL, Han Y, Desjardins B, Trayanova N, Nazarian S. Conduction Velocity Dispersion Predicts Postinfarct Ventricular Tachycardia Circuit Sites and Associates With Lipomatous Metaplasia. JACC Clin Electrophysiol 2023; 9:1464-1474. [PMID: 37294264 PMCID: PMC11149171 DOI: 10.1016/j.jacep.2023.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 05/09/2023] [Accepted: 05/10/2023] [Indexed: 06/10/2023]
Abstract
BACKGROUND Regional myocardial conduction velocity (CV) dispersion has not been studied in postinfarct patients with ventricular tachycardia (VT). OBJECTIVES This study sought to compare the following: 1) the association of CV dispersion vs repolarization dispersion with VT circuit sites; and 2) myocardial lipomatous metaplasia (LM) vs fibrosis as the anatomic substrate for CV dispersion. METHODS Among 33 postinfarct patients with VT, we characterized dense and border zone infarct tissue by late gadolinium enhancement cardiac magnetic resonance, and LM by computed tomography, with both images registered with electroanatomic maps. Activation recovery interval (ARI) was the time interval from the minimum derivative within the QRS complex to the maximum derivative within the T-wave on unipolar electrograms. CV at each EAM point was the mean CV between that point and 5 adjacent points along the activation wave front. CV and ARI dispersion were the coefficient of variation (CoV) of CV and ARI per American Heart Association (AHA) segment, respectively. RESULTS Regional CV dispersion exhibited a much larger range than ARI dispersion, with median 0.65 vs 0.24; P < 0.001. CV dispersion was a more robust predictor of the number of critical VT sites per AHA segment than ARI dispersion. Regional LM area was more strongly associated with CV dispersion than fibrosis area. LM area was larger (median 0.44 vs 0.20 cm2; P < 0.001) in AHA segments with mean CV <36 cm/s and CoV_CV >0.65 than those with mean CV <36 cm/s and CoV_CV <0.65. CONCLUSIONS Regional CV dispersion more strongly predicts VT circuit sites than repolarization dispersion, and LM is a critical substrate for CV dispersion.
Collapse
Affiliation(s)
- Lingyu Xu
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
| | - Sohail Zahid
- Department of Internal Medicine, NYU Langone Medical Center, New York, New York, USA
| | - Mirmilad Khoshknab
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Juwann Moss
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Ronald D Berger
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cardiology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jonathan Chrispin
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cardiology, Johns Hopkins University, Baltimore, Maryland, USA
| | - David Callans
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Francis E Marchlinski
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Stefan L Zimmerman
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Yuchi Han
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Benoit Desjardins
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Natalia Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Saman Nazarian
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA. https://twitter.com/Dr_Nazarian_EP
| |
Collapse
|
8
|
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.
| |
Collapse
|
9
|
Xu L, Zahid S, Khoshknab M, Moss J, Berger RD, Chrispin J, Callans D, Marchlinski FE, Zimmerman SL, Han Y, Desjardins B, Trayanova N, Nazarian S. Lipomatous metaplasia prolongs repolarization and increases repolarization dispersion within post-infarct ventricular tachycardia circuit cites. Europace 2023; 25:496-505. [PMID: 36519747 PMCID: PMC9935002 DOI: 10.1093/europace/euac222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/20/2022] [Indexed: 12/23/2022] Open
Abstract
AIMS Post-infarct myocardium contains viable corridors traversing scar or lipomatous metaplasia (LM). Ventricular tachycardia (VT) circuitry has been separately reported to associate with corridors that traverse LM and with repolarization heterogeneity. We examined the association of corridor activation recovery interval (ARI) and ARI dispersion with surrounding tissue type. METHODS AND RESULTS The cohort included 33 post-infarct patients from the prospective Intra-Myocardial Fat Deposition and Ventricular Tachycardia in Cardiomyopathy (INFINITY) study. We co-registered scar and corridors from late gadolinium enhanced magnetic resonance, and LM from computed tomography with intracardiac electrogram locations. Activation recovery interval was calculated during sinus or ventricular pacing, as the time interval from the minimum derivative within the QRS to the maximum derivative within the T-wave on unipolar electrograms. Regional ARI dispersion was defined as the standard deviation (SD) of ARI per AHA segment (ARISD). Lipomatous metaplasia exhibited higher ARI than scar [325 (interquartile range 270-392) vs. 313 (255-374), P < 0.001]. Corridors critical to VT re-entry were more likely to traverse through or near LM and displayed prolonged ARI compared with non-critical corridors [355 (319-397) vs. 302 (279-333) ms, P < 0.001]. ARISD was more closely associated with LM than with scar (likelihood ratio χ2 50 vs. 12, and 4.2-unit vs. 0.9-unit increase in 0.01*Log(ARISD) per 1 cm2 increase per AHA segment). Additionally, LM and scar exhibited interaction (P < 0.001) in their association with ARISD. CONCLUSION Lipomatous metaplasia is closely associated with prolonged local action potential duration of corridors and ARI dispersion, which may facilitate the propensity of VT circuit re-entry.
Collapse
Affiliation(s)
- Lingyu Xu
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Sohail Zahid
- Department of Internal Medicine, NYU Langone Medical Center, New York, NY, USA
| | - Mirmilad Khoshknab
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Juwann Moss
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Ronald D Berger
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Department of Cardiology, Johns Hopkins University, Baltimore, MD, USA
| | - Jonathan Chrispin
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Department of Cardiology, Johns Hopkins University, Baltimore, MD, USA
| | - David Callans
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Francis E Marchlinski
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Stefan L Zimmerman
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Yuchi Han
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Benoit Desjardins
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Natalia Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Saman Nazarian
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA
| |
Collapse
|
10
|
Vlachos K, Letsas KP, Srinivasan NT, Frontera A, Efremidis M, Dragasis S, Martin CA, Martin R, Nakashima T, Bazoukis G, Kitamura T, Mililis P, Saplaouras A, Georgopoulos S, Sofoulis S, Kariki O, Koskina S, Takigawa M, Sacher F, Jais P, Santangeli P. The value of functional substrate mapping in ventricular tachycardia ablation. Heart Rhythm O2 2023; 4:134-146. [PMID: 36873315 PMCID: PMC9975018 DOI: 10.1016/j.hroo.2022.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
In the setting of structural heart disease, ventricular tachycardia (VT) is typically associated with a re-entrant mechanism. In patients with hemodynamically tolerated VTs, activation and entrainment mapping remain the gold standard for the identification of the critical parts of the circuit. However, this is rarely accomplished, as most VTs are not hemodynamically tolerated to permit mapping during tachycardia. Other limitations include noninducibility of arrhythmia or nonsustained VT. This has led to the development of substrate mapping techniques during sinus rhythm, eliminating the need for prolonged periods of mapping during tachycardia. Recurrence rates following VT ablation are high; therefore, new mapping techniques for substrate characterization are required. Advances in catheter technology and especially multielectrode mapping of abnormal electrograms has increased the ability to identify the mechanism of scar-related VT. Several substrate-guided approaches have been developed to overcome this, including scar homogenization and late potential mapping. Dynamic substrate changes are mainly identified within regions of myocardial scar and can be identified as local abnormal ventricular activities. Furthermore, mapping strategies incorporating ventricular extrastimulation, including from different directions and coupling intervals, have been shown to increase the accuracy of substrate mapping. The implementation of extrastimulus substrate mapping and automated annotation require less extensive ablation and would make VT ablation procedures less cumbersome and accessible to more patients.
Collapse
Affiliation(s)
- Konstantinos Vlachos
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
- Address reprint requests and correspondence: Dr Konstantinos Vlachos, Onassis Cardiac Surgery Center, Electrophysiology Department, Syggrou Avenue 356, PC 176 74, Athens, Greece.
| | | | - Neil T. Srinivasan
- Department of Cardiac Electrophysiology, Essex Cardiothoracic Centre, Basildon, United Kingdom
- Royal Papworth Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - Antonio Frontera
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Michael Efremidis
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | - Stelios Dragasis
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | - Claire A. Martin
- Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia, Cyprus
| | - Ruaridh Martin
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Takashi Nakashima
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - George Bazoukis
- Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia, Cyprus
- Department of Cardiology, Larnaca General Hospital, Larnaca, Cyprus
| | - Takeshi Kitamura
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Panagiotis Mililis
- Laboratory of Cardiac Electrophysiology, General Hospital of Athens Evangelismos, Athens, Greece
| | | | - Stamatios Georgopoulos
- Laboratory of Cardiac Electrophysiology, General Hospital of Athens Evangelismos, Athens, Greece
| | - Stamatios Sofoulis
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | - Ourania Kariki
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | - Stavroula Koskina
- Electrophysiology Department, Onassis Cardiac Surgery Center, Athens, Greece
| | - Masateru Takigawa
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Frédéric Sacher
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Pierre Jais
- Cardiac Pacing and Electrophysiology Department, Hôpital Cardiologique du Haut Lévêque, Pessac, France
- INSERM U1045, Institut hostpialo-universitaire–L’institut de rythmologie et modélisation cardiaque, Centre Hospitalier Universitaire de Bordeaux, Université de Bordeaux, Pessac, France
| | - Pasquale Santangeli
- Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Hoang JD, Yamakawa K, Rajendran PS, Chan CA, Yagishita D, Nakamura K, Lux RL, Vaseghi M. Proarrhythmic Effects of Sympathetic Activation Are Mitigated by Vagal Nerve Stimulation in Infarcted Hearts. JACC Clin Electrophysiol 2022; 8:513-525. [PMID: 35450607 PMCID: PMC9034056 DOI: 10.1016/j.jacep.2022.01.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 10/18/2022]
Abstract
OBJECTIVES The goal of this study was to evaluate whether intermittent VNS reduces electrical heterogeneities and arrhythmia inducibility during sympathoexcitation. BACKGROUND Sympathoexcitation increases the risk of ventricular tachyarrhythmias (VT). Vagal nerve stimulation (VNS) has been antiarrhythmic in the setting of ischemia-driven arrhythmias, but it is unclear if it can overcome the electrophysiological effects of sympathoexcitation in the setting of chronic myocardial infarction (MI). METHODS In Yorkshire pigs after chronic MI, a sternotomy was performed, a 56-electrode sock was placed over the ventricles (n = 17), and a basket catheter was positioned in the left ventricle (n = 6). Continuous unipolar electrograms from sock and basket arrays were obtained to analyze activation recovery interval (ARI), a surrogate of action potential duration. Bipolar voltage mapping was performed to define scar, border zone, or viable myocardium. Hemodynamic and electrical parameters and VT inducibility were evaluated during sympathoexcitation with bilateral stellate ganglia stimulation (BSS) and during combined BSS with intermittent VNS. RESULTS During BSS, global epicardial ARIs shortened from 384 ± 59 milliseconds to 297 ± 63 milliseconds and endocardial ARIs from 359 ± 36 milliseconds to 318 ± 40 milliseconds. Dispersion in ARIs increased in all regions, with the greatest increase observed in scar and border zone regions. VNS mitigated the effects of BSS on border zone ARIs (from -18.3% ± 6.3% to -2.1% ± 14.7%) and ARI dispersion (from 104 ms2 [1 to 1,108 ms2] to -108 ms2 [IQR: -588 to 30 ms2]). VNS reduced VT inducibility during sympathoexcitation (from 75%-40%; P < 0.05). CONCLUSIONS After chronic MI, VNS overcomes the detrimental effects of sympathoexcitation by reducing electrophysiological heterogeneities exacerbated by sympathetic stimulation, decreasing VT inducibility.
Collapse
Affiliation(s)
- Jonathan D Hoang
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA; UCLA Neurocardiology Program of Excellence, University of California, Los Angeles, California, USA; Molecular, Cellular and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, California, USA
| | - Kentaro Yamakawa
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA
| | - Pradeep S Rajendran
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA; UCLA Neurocardiology Program of Excellence, University of California, Los Angeles, California, USA
| | - Christopher A Chan
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA; UCLA Neurocardiology Program of Excellence, University of California, Los Angeles, California, USA
| | - Daigo Yagishita
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA
| | - Keijiro Nakamura
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA
| | - Robert L Lux
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA
| | - Marmar Vaseghi
- UCLA Cardiac Arrhythmia Center, University of California, Los Angeles, California, USA; UCLA Neurocardiology Program of Excellence, University of California, Los Angeles, California, USA; Molecular, Cellular and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, California, USA.
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Papageorgiou N, Srinivasan NT. Dynamic High-density Functional Substrate Mapping Improves Outcomes in Ischaemic Ventricular Tachycardia Ablation: Sense Protocol Functional Substrate Mapping and Other Functional Mapping Techniques. Arrhythm Electrophysiol Rev 2021; 10:38-44. [PMID: 33936742 PMCID: PMC8076974 DOI: 10.15420/aer.2020.28] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Post-infarct-related ventricular tachycardia (VT) occurs due to reentry over surviving fibres within ventricular scar tissue. The mapping and ablation of patients in VT remains a challenge when VT is poorly tolerated and in cases in which VT is non-sustained or not inducible. Conventional substrate mapping techniques are limited by the ambiguity of substrate characterisation methods and the variety of mapping tools, which may record signals differently based on their bipolar spacing and electrode size. Real world data suggest that outcomes from VT ablation remain poor in terms of freedom from recurrent therapy using conventional techniques. Functional substrate mapping techniques, such as single extrastimulus protocol mapping, identify regions of unmasked delayed potentials, which, by nature of their dynamic and functional components, may play a critical role in sustaining VT. These methods may improve substrate mapping of VT, potentially making ablation safer and more reproducible, and thereby improving the outcomes. Further large-scale studies are needed.
Collapse
Affiliation(s)
- Nikolaos Papageorgiou
- Department of Cardiac Electrophysiology, Barts Heart Centre, St Bartholomew's Hospital, London, UK
| | - Neil T Srinivasan
- Department of Cardiac Electrophysiology, Barts Heart Centre, St Bartholomew's Hospital, London, UK.,Institute of Cardiovascular Science, University College London, London, UK.,Department of Cardiac Electrophysiology, Essex Cardiothoracic Centre, Basildon, UK
| |
Collapse
|
15
|
Song ZL, Liu Y, Liu X, Qin M. Absence of Rgs5 Influences the Spatial and Temporal Fluctuation of Cardiac Repolarization in Mice. Front Physiol 2021; 12:622084. [PMID: 33815137 PMCID: PMC8012757 DOI: 10.3389/fphys.2021.622084] [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: 10/27/2020] [Accepted: 02/22/2021] [Indexed: 11/25/2022] Open
Abstract
Aims This study investigated the contribution of the regulator of G-protein signaling 5 (Rgs5) knockout to the alteration of the action potential duration (APD) restitution and repolarizing dispersion in ventricle. Methods and Results The effects of Rgs5–/– were investigated by QT variance (QTv) and heart rate variability analysis of Rgs5–/– mice. Monophasic action potential analysis was investigated in isolated Rgs5–/– heart. Rgs5–/– did not promote ventricular remodeling. The 24-h QTv and QT variability index (QTVI) of the Rgs5–/– mice were higher than those of wild-type (WT) mice (P < 0.01). In WT mice, a positive correlation was found between QTv and the standard deviation of all NN intervals (r = 0.62; P < 0.01), but not in Rgs5–/– mice (R = 0.01; P > 0.05). The absence of Rgs5 resulted in a significant prolongation of effective refractory period and APD in isolated ventricle. In addition, compared with WT mice, the knockout of Rgs5 significantly deepened the slope of the APD recovery curve at all 10 sites of the heart (P < 0.01) and increased the spatial dispersions of Smax (COV-Smax) (WT: 0.28 ± 0.03, Rgs5–/–: 0.53 ± 0.08, P < 0.01). Compared with WT heart, Rgs5–/– increased the induced S1–S2 interval at all sites of heart and widened the window of vulnerability of ventricular tachyarrhythmia (P < 0.05). Conclusion Our findings indicate that Rgs5–/– is an important regulator of ventricular tachyarrhythmia in mice by prolonging ventricular repolarization and increasing spatial dispersion in ventricle.
Collapse
Affiliation(s)
- Zi-Liang Song
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yang Liu
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Xu Liu
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Mu Qin
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
16
|
Srinivasan NT, Garcia J, Schilling RJ, Ahsan S, Babu GG, Ang R, Dhinoja MB, Hunter RJ, Lowe M, Chow AW, Lambiase PD. Multicenter Study of Dynamic High-Density Functional Substrate Mapping Improves Identification of Substrate Targets for Ischemic Ventricular Tachycardia Ablation. JACC Clin Electrophysiol 2020; 6:1783-1793. [PMID: 33357574 PMCID: PMC7769061 DOI: 10.1016/j.jacep.2020.06.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The goal of this study was to evaluate the role of dynamic substrate changes in facilitating conduction delay and re-entry in ventricular tachycardia (VT) circuits. BACKGROUND The presence of dynamic substrate changes facilitate functional block and re-entry in VT but are rarely studied as part of clinical VT mapping. METHODS Thirty patients (age 67 ± 9 years; 27 male subjects) underwent ablation. Mapping was performed with the Advisor HD Grid multipolar catheter. A bipolar voltage map was obtained during sinus rhythm (SR) and right ventricular sense protocol (SP) single extra pacing. SR and SP maps of late potentials (LP) and local abnormal ventricular activity (LAVA) were made and compared with critical sites for ablation, defined as sites of best entrainment or pace mapping. Ablation was then performed to critical sites, and LP/LAVA identified by the SP. RESULTS At a median follow-up of 12 months, 90% of patients were free from antitachycardia pacing (ATP) or implantable cardioverter-defibrillator shocks. SP pacing resulted in a larger area of LP identified for ablation (19.3 mm2 vs. 6.4 mm2) during SR mapping (p = 0.001), with a sensitivity of 87% and a specificity of 96%, compared with 78% and 65%, respectively, in SR. CONCLUSIONS LP and LAVA observed during the SP were able to identify regions critical for ablation in VT with a greater accuracy than SR mapping. This may improve substrate characterization in VT ablation. The combination of ablation to critical sites and SP-derived LP/LAVA requires further assessment in a randomized comparator study.
Collapse
Affiliation(s)
- Neil T Srinivasan
- 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.
| | - 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
| | - Girish G Babu
- Royal Bournemouth and Christchurch Hospitals, Bournemouth, United Kingdom
| | - Richard Ang
- Department of Cardiac Electrophysiology, The Barts Heart Center, St. Bartholomew's Hospital, London, United Kingdom
| | - Mehul B Dhinoja
- 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
| |
Collapse
|
17
|
Krishnappa D, Akdemir B, Nantsupawat T, Krishnan B, Can I, Adabag S, Li JM, Tholakanahalli VN. QTc dispersion as a novel marker in identifying patients requiring an epicardial approach for ablation of scar mediated ventricular tachycardia. Indian Pacing Electrophysiol J 2020; 20:141-146. [PMID: 32156639 PMCID: PMC7384369 DOI: 10.1016/j.ipej.2020.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/20/2020] [Accepted: 03/04/2020] [Indexed: 12/02/2022] Open
Abstract
Introduction Epicardial exit sites of ventricular tachycardia (VT) are frequently encountered during VT ablation requiring an epicardial ablation approach for successful elimination of VT. We sought to assess the utility of repolarization markers in identifying individuals requiring an epicardial ablation approach in addition to an endocardial approach. Methods 32 patients who underwent successful ablation for scar mediated VT were included in the study. Fourteen patients who required a combined endocardial and epicardial VT ablation were defined as epicardial VT group (Epi) whereas 18 patients who were successfully ablated from the endocardium alone constituted the endocardial VT group (Endo). Repolarization markers during sinus rhythm were compared between the two groups. Results A higher QTc max and QTc dispersion were seen in the Epi group compared to Endo group (479 ± 34 vs 449 ± 20, p = 0.008 and 63 ± 13 vs 38 ± 8, p = 0.001, respectively). Ts-p and Ts-p/Tp-e were higher in the Epi group (166 ± 23 vs 143 ± 23, p = 0.008 and 1.55 ± 0.26 vs 1.3 ± 0.21, p < 0.005). On multivariate regression, QTc dispersion was an independent predictor of the need for an epicardial approach to ablation. A QTc dispersion more than 51.5 msec identified individuals requiring a combined epicardial and endocardial approach to ablation with a sensitivity of 92.9% and a specificity of 100%. Conclusions Patients requiring an epicardial ablation have a higher QTc dispersion. A value greater than 51.5 msec reliably differentiates between the two groups with high sensitivity and specificity.
Collapse
|
18
|
Tse G, Lee S, Gong M, Mililis P, Asvestas D, Bazoukis G, Roever L, Jeevaratnam K, Hothi SS, Li KHC, Liu T, Letsas KP. Restitution metrics in Brugada syndrome: a systematic review and meta-analysis. J Interv Card Electrophysiol 2019; 57:319-327. [PMID: 31836966 DOI: 10.1007/s10840-019-00675-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/19/2019] [Indexed: 12/15/2022]
Abstract
BACKGROUND Brugada syndrome (BrS) is an ion channelopathy that predisposes affected subjects to ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death. Restitution analysis has been examined in BrS patients but not all studies have reported significant differences between BrS patients and controls. Therefore, we conducted a systematic review and meta-analysis to investigate the different restitution indices used in BrS. METHODS PubMed and Embase were searched until April 7, 2019, identifying 20 and 27 studies. RESULTS A total of ten studies involving 178 BrS (mean age 38 years old, 63% male) and 102 controls (mean age 31 years old, 42% male) were included in this systematic review. Pacing was carried out at the right ventricular outflow tract (RVOT)/right ventricular apex (RPA) (n = 4), RPA (n = 4), or right atrium (RA) (n = 1). Basic cycle lengths of 400 (n = 4), 500 (n = 2), 600 (n = 6) and 750 ms (n = 1) were used. Recording methods include electrograms (n = 4), monophasic action potentials (n = 5), and electrocardiograms (n = 1). Signals were obtained from the RVOT (n = 8), RVA (n = 3), RA (n = 1), or the body surface (n = 1). The maximum restitution slope for endocardial repolarization at the RVOT was 0.87 for BrS patients (n = 5; 95% confidence interval [CI] 0.68-1.07) compared with 0.74 in control subjects (n = 4; 95% CI 0.42-1.06), with a significant mean difference of 0.40 (n = 4; 95% CI 0.11-0.69; P = 0.007). CONCLUSIONS Steeper endocardial repolarization restitution slopes are found in BrS patients compared with controls at baseline. Restitution analysis can provide important information for risk stratification in BrS.
Collapse
Affiliation(s)
- Gary Tse
- Xiamen Cardiovascular Hospital Affiliated to Xiamen University, Xiamen, Fujian, People's Republic of China. .,Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, People's Republic of China.
| | - Sharen Lee
- Laboratory of Cardiovascular Physiology, Li Ka Shing Institute of Health Sciences, Hong Kong, SAR, People's Republic of China
| | - Mengqi Gong
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, People's Republic of China
| | - Panagiotis Mililis
- Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece
| | - Dimitrios Asvestas
- Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece
| | - George Bazoukis
- Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece
| | - Leonardo Roever
- Department of Clinical Research, Federal University of Uberlândia, Uberlândia, MG, Brazil
| | | | - Sandeep S Hothi
- Heart and Lung Centre, New Cross Hospital, Wolverhampton, UK
| | - Ka Hou Christien Li
- Xiamen Cardiovascular Hospital Affiliated to Xiamen University, Xiamen, Fujian, People's Republic of China.,Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, People's Republic of China.,Faculty of Medicine, Newcastle University, Newcastle, UK
| | - Tong Liu
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, 300211, People's Republic of China
| | - Konstantinos P Letsas
- Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece.
| |
Collapse
|