1
|
Zhang L, van Schie MS, Knops P, Taverne YJHJ, de Groot NMS. A novel diagnostic tool to identify atrial endo-epicardial asynchrony using signal fingerprinting. Hellenic J Cardiol 2024; 75:9-20. [PMID: 37482189 DOI: 10.1016/j.hjc.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/04/2023] [Accepted: 07/18/2023] [Indexed: 07/25/2023] Open
Abstract
OBJECTIVE Patients with persistent atrial fibrillation (AF) have more electrical endo-epicardial asynchrony (EEA) during sinus rhythm (SR) than patients without AF. Prior mapping studies indicated that particularly unipolar, endo- and/or epicardial electrogram (EGM) morphology may be indicators of EEA. This study aim to develop a novel method for estimating the degree of EEA by using unipolar EGM characteristics recorded from either the endo- and/or epicardium. METHODS Simultaneous endo-epicardial mapping during sinus rhythm was performed in 86 patients. EGM characteristics, including unipolar voltages, low-voltage areas (LVAs), potential types (single, short/long double and fractionated potentials: SP, SDP, LDP and FP) and fractionation duration (FD) of double potentials (DP) and FP were compared between EEA and non-EEA areas. Asynchrony Fingerprinting Scores (AFS) containing quantified EGM characteristics were constructed to estimate the degree of EEA. RESULTS Endo- and epicardial sites of EEA areas are characterized by lower unipolar voltages, a higher number of LDPs and FPs and longer DP and FP durations. Patients with AF have lower potential voltages in EEA areas, along with alterations in the potential types. The EE-AFS, containing the proportion of endocardial LVAs and FD of epicardial DPs, had the highest predictive value for determining the degree of EEA (AUC: 0.913). Endo- and epi-AFS separately also showed good predictive values (AUC: 0.901 and 0.830 respectively). CONCLUSIONS EGM characteristics can be used to identify EEA areas. AFS can be utilized as a novel diagnostic tool for accurately estimating the degree of EEA. These characteristics potentially indicate AF related arrhythmogenic substrates.
Collapse
Affiliation(s)
- Lu Zhang
- Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Mathijs S van Schie
- Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Paul Knops
- Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Yannick J H J Taverne
- Translational Cardiothoracic Surgery Research Lab, Department of Cardiothoracic Surgery, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Natasja M S de Groot
- Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands; Department of Microelectronics, Signal Processing Systems, Faculty of Electrical Engineering, Mathematics and Computer Sciences, Delft University of Technology, Delft, the Netherlands.
| |
Collapse
|
2
|
Liu QF, Tian Y, Tian LH, Jing H. Unipolar and bipolar electrograms to predict successful ablation site of premature ventricular contractions originating from the free wall of the tricuspid annulus. J Cardiovasc Electrophysiol 2023; 34:1843-1849. [PMID: 37632286 DOI: 10.1111/jce.16042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/27/2023] [Accepted: 08/13/2023] [Indexed: 08/27/2023]
Abstract
INTRODUCTION This study aimed to identify the characteristics of unipolar and bipolar electrogram (UniEGM and BiEGM) in guiding successful ablation of premature ventricular contractions (PVCs) originating from the free wall of the ventricular aspect of the tricuspid annulus (TA). We hypothesized that the negative concordance pattern (NCP) on the onset of UniEGM and BiEGM, together with the least value of the difference between the earliest BiEGM and UniEGM dV/dTmax, might improve the accuracy of conventional mapping. METHODS AND RESULTS Thirty consecutive patients who underwent successful catheter ablation from February 2018 to July 2021 were retrospectively analyzed. The BiEGM and UniEGM for successful ablation sites were compared with those for non-successful ablation sites. Among the 30 patients, 30 successful and 26 nonsuccessful ablation sites were compared. The earliest activation time of the BiEGM (BiEGMoneset-QRS) was 25 ± 6 ms for the successful ablation sites and 21 ± 6 ms for the nonsuccessful ablation sites (p = .47). The value of the difference in the earliest BiEGM and UniEGM dV/dTmax differed between successful and nonsuccessful ablation sites (6.4 ± 3.6 ms vs. 10.4 ± 6.8 ms). NCP was observed at 90.0% and 42.3% of the successful and nonsuccessful ablation sites, respectively. Alignment of NCP and BiEGMonset-UniEGM ≤6 ms was applied as the mapping criterion for successful PVC suppression (73.1% sensitivity and 87.7% specificity). The area under the receiver-operating characteristic curve for this cutoff was 0.85. CONCLUSION Mapping based on an NCP at the onset of the BiEGM and UniEGM and the least difference value of the earliest BiEGM and UniEGM dV/dTmax had an excellent predictive value for successful ablation. These strategies may reduce the number of radiofrequency catheter ablation (RFCA) applications for free-wall tricuspid annular PVCs.
Collapse
Affiliation(s)
- Qi-Fang Liu
- Department of Cardiology, Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China
| | - Ye Tian
- Department of Cardiology, Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China
| | - Long-Hai Tian
- Department of Cardiology, Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China
| | - Huang Jing
- Department of Cardiology, Guizhou Provincial People's Hospital, Guiyang, 550002, Guizhou, China
| |
Collapse
|
3
|
Vermoortele D, Amoni M, Ingelaere S, Sipido KR, Willems R, Claus P. Electric Field-Based Spatial Analysis of Noncontact Unipolar Electrograms to Map Regional Activation-Repolarization Intervals. JACC Clin Electrophysiol 2023; 9:1217-1231. [PMID: 37558285 DOI: 10.1016/j.jacep.2023.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/30/2023] [Accepted: 02/01/2023] [Indexed: 08/11/2023]
Abstract
BACKGROUND Spatial heterogeneity in repolarization plays an important role in generating and sustaining cardiac arrhythmias. Reliable determination of repolarization times remains challenging. OBJECTIVES The goal of this study was to improve processing of densely sampled noncontact unipolar electrograms to yield reliable high-resolution activation and repolarization maps. METHODS Endocardial noncontact unipolar electrograms were both simulated and recorded in pig left ventricle. Electrical activity on the endocardial surface was processed in terms of a pseudo-electric field. Activation and repolarization times were calculated by using an amplitude-weighted average on QRS and T waves (ie, the E-field method). This was compared vs the conventional Wyatt method on unipolar electrograms. Timing maps were validated against timing on endocardial action potentials in a simulation study. In vivo, activation and repolarization times determined by using this alternative E-field method were validated against simultaneously recorded endocardial monophasic action potentials (MAPs). RESULTS Simulation showed that the E-field method provides viable measurements of local endocardial action potential activation and repolarization times. In vivo, correlation of E-field activation times with MAP activation times (rE = 0.76; P < 0.001) was similar to those of Wyatt (rWyatt = 0.80, P < 0.001; P[h1:rE > rWyatt] = 0.82); for repolarization times, correlation improved significantly (rE = 0.96, P < 0.001; rWyatt = 0.82, P < 0.001; P[h1:rE > rWyatt] < 0.00001). This resulted in improved correlations of activation-repolarization intervals to endocardial action potential duration on MAP (rE = 0.96, P < 0.001; rWyatt = 0.86, P < 0.001; P[h1:rE > rWyatt] < 0.00001). Spatial beat-to-beat variation of repolarization could only be calculated by using the E-field methodology and correlated well with the MAP beat-to-beat variation of repolarization (rE = 0.76; P = 0.001). CONCLUSIONS The E-field method substantially enhances information from endocardial noncontact electrogram data, allowing for dense maps of activation and repolarization times and derived parameters.
Collapse
Affiliation(s)
- Dylan Vermoortele
- Department of Cardiovascular Sciences, Cardiovascular Imaging and Dynamics, KU Leuven, Leuven, Belgium
| | - Matthew Amoni
- Department of Cardiovascular Sciences, Experimental Cardiology, KU Leuven, Leuven, Belgium
| | - Sebastian Ingelaere
- Department of Cardiovascular Sciences, Experimental Cardiology, KU Leuven, Leuven, Belgium; Division of Cardiology, University Hospitals Leuven, Leuven, Belgium
| | - Karin R Sipido
- Department of Cardiovascular Sciences, Experimental Cardiology, KU Leuven, Leuven, Belgium
| | - Rik Willems
- Department of Cardiovascular Sciences, Experimental Cardiology, KU Leuven, Leuven, Belgium; Division of Cardiology, University Hospitals Leuven, Leuven, Belgium
| | - Piet Claus
- Department of Cardiovascular Sciences, Cardiovascular Imaging and Dynamics, KU Leuven, Leuven, Belgium.
| |
Collapse
|
4
|
Bruce CG, Yildirim DK, Kolandaivelu A, Khan JM, Rogers T, Uzun D, Jaimes AE, Halaby RN, Herzka DA, Babaliaros VC, Greenbaum AB, Lederman RJ. EDEN (Electrocardiographic Radial Depth Navigation): A Novel Approach to Navigate Inside Heart Muscle. JACC Clin Electrophysiol 2023; 9:1741-1754. [PMID: 37354176 PMCID: PMC10524151 DOI: 10.1016/j.jacep.2023.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/04/2023] [Accepted: 04/21/2023] [Indexed: 06/26/2023]
Abstract
BACKGROUND Intramyocardial guidewire navigation is a novel technique that allows free transcatheter movement within ventricular muscle. Guidewire radial depth, between endocardial and epicardial surfaces, is ambiguous by x-ray and echocardiography. OBJECTIVES The aim of this study was to develop a simple tool, EDEN (Electrocardiographic Radial Depth Navigation), to indicate radial depth during intramyocardial guidewire navigation. Combined with routine imaging, EDEN facilitates a new family of intramyocardial catheter procedures to slice, reshape, pace, and ablate the heart. METHODS We mapped intramyocardial electrograms of left and right ventricular walls and septum during open- and closed-chest swine procedures (N = 53), including MIRTH (Myocardial Intramural Remodeling by Transvenous Tether) ventriculoplasty. We identified radial depth-dependent features on unipolar electrograms. We developed a machine learning-based classifier to indicate categorical position, and modeled the findings in silico to test understanding of the physiology. RESULTS EDEN signatures distinguished 5 depth zones throughout left and right ventricular free walls and interventricular septum. Relative ST-segment elevation magnitude best discriminated position and was maximum (40.1 ± 6.5 mV) in the midmyocardium. Subendocardial positions exhibited dominant Q waves with lower-amplitude ST segments (16.8 ± 5.8 mV), whereas subepicardial positions exhibited dominant R waves with lower-amplitude ST segments (15.7 ± 4.8 mV). EDEN was unaffected by pacing-induced left bundle branch block. ST-segment elevation declined over minutes and reappeared after submillimeter guidewire manipulation. Modeling recapitulated EDEN features. The machine learning-based classifier was 97% accurate. EDEN successfully guided MIRTH ventriculoplasty. CONCLUSIONS EDEN provides a simple and reproducible real-time reflection of categorical guidewire-tip radial depth during intramyocardial guidewire navigation. Used in tandem with x-ray, EDEN enables novel, transcatheter, intramyocardial therapies such as MIRTH, SESAME (Septal Surfing Along Midline Endocardium), and cerclage ventriculoplasty.
Collapse
Affiliation(s)
- Christopher G Bruce
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA. https://twitter.com/ChrisGBruce13
| | - D Korel Yildirim
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Aravindan Kolandaivelu
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Johns Hopkins Medical Center, Baltimore, Maryland, USA
| | - Jaffar M Khan
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Toby Rogers
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; MedStar Washington Hospital Center, Washington, DC, USA
| | - Dogangun Uzun
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Andrea E Jaimes
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Rim N Halaby
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Daniel A Herzka
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Vasilis C Babaliaros
- Structural Heart and Valve Center, Emory University Hospital, Atlanta, Georgia, USA
| | - Adam B Greenbaum
- Structural Heart and Valve Center, Emory University Hospital, Atlanta, Georgia, USA
| | - Robert J Lederman
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
| |
Collapse
|
5
|
Riccio J, Alcaine A, Rocher S, Martinez-Mateu L, Laranjo S, Saiz J, Laguna P, Martínez JP. Characterization of Atrial Propagation Patterns and Fibrotic Substrate With a Modified Omnipolar Electrogram Strategy in Multi-Electrode Arrays. Front Physiol 2021; 12:674223. [PMID: 34539424 PMCID: PMC8446360 DOI: 10.3389/fphys.2021.674223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 07/13/2021] [Indexed: 11/15/2022] Open
Abstract
Introduction: The omnipolar electrogram method was recently proposed to try to generate orientation-independent electrograms. It estimates the electric field from the bipolar electrograms of a clique, under the assumption of locally plane and homogeneous propagation. The local electric field evolution over time describes a loop trajectory from which omnipolar signals in the propagation direction, substrate and propagation features, are derived. In this work, we propose substrate and conduction velocity mapping modalities based on a modified version of the omnipolar electrogram method, which aims to reduce orientation-dependent residual components in the standard approach. Methods: A simulated electrical propagation in 2D, with a tissue including a circular patch of diffuse fibrosis, was used for validation. Unipolar electrograms were calculated in a multi-electrode array, also deriving bipolar electrograms along the two main directions of the grid. Simulated bipolar electrograms were also contaminated with real noise, to assess the robustness of the mapping strategies against noise. The performance of the maps in identifying fibrosis and in reproducing unipolar reference voltage maps was evaluated. Bipolar voltage maps were also considered for performance comparison. Results: Results show that the modified omnipolar mapping strategies are more accurate and robust against noise than bipolar and standard omnipolar maps in fibrosis detection (accuracies higher than 85 vs. 80% and 70%, respectively). They present better correlation with unipolar reference voltage maps than bipolar and original omnipolar maps (Pearson's correlations higher than 0.75 vs. 0.60 and 0.70, respectively). Conclusion: The modified omnipolar method improves fibrosis detection, characterization of substrate and propagation, also reducing the residual sensitivity to directionality over the standard approach and improving robustness against noise. Nevertheless, studies with real electrograms will elucidate its impact in catheter ablation interventions.
Collapse
Affiliation(s)
- Jennifer Riccio
- Biomedical Signal Interpretation and Computational Simulation Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Alejandro Alcaine
- Biomedical Signal Interpretation and Computational Simulation Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,Facultad de Ciencias de la Salud, Universidad San Jorge, Zaragoza, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain
| | - Sara Rocher
- Centro de Investigación e Innovación en Ingeniería, Universitat Politècnica de València, Valencia, Spain
| | - Laura Martinez-Mateu
- Departamento de Teoría de la Señal y Comunicaciones y Sistemas Telemáticos y Computación, Universidad Rey Juan Carlos, Madrid, Spain
| | - Sergio Laranjo
- Department of Pediatric Cardiology, Hospital Santa Marta, Centro Hospitalar de Lisboa Central, Lisbon, Portugal
| | - Javier Saiz
- Centro de Investigación e Innovación en Ingeniería, Universitat Politècnica de València, Valencia, Spain
| | - Pablo Laguna
- Biomedical Signal Interpretation and Computational Simulation Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain
| | - Juan Pablo Martínez
- Biomedical Signal Interpretation and Computational Simulation Group, Aragón Institute of Engineering Research, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza, Spain
| |
Collapse
|
6
|
Ríos-Muñoz GR, Artés-Rodríguez A, Fernández-Avilés F, Arenal Á. Real-Time Ventricular Cancellation in Unipolar Atrial Fibrillation Electrograms. Front Bioeng Biotechnol 2020; 8:789. [PMID: 32850699 PMCID: PMC7406791 DOI: 10.3389/fbioe.2020.00789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/22/2020] [Indexed: 11/13/2022] Open
Abstract
Unipolar atrial fibrillation (AF) electrograms (EGMs) require far-field ventricle cancellation to recover hidden atrial activations. Current methods cannot achieve real-time cancellation because of the temporal delay they introduce. We propose a new real-time ventricular cancellation (RVC) method based on causal implementation optimized for real-time functioning. The method is similar to the classical average beat subtraction (ABS) method but it computes the ventricular contribution before the ventricular activation finishes. We compare the proposed method to the ABS on synthetic and real EGM databases for the time and frequency domains. All parameters and their optimal values are analyzed and validated. The RVC method provides a good reconstruction of the unipolar EGMs and a better local activation time detection than the classical approach with average F1scores 0.7307 and 0.7125, respectively. The spectral analysis shows that the average power after ventricular cancellation is reduced for frequency bands between 3 and 5.5 Hz, demonstrating that the proposed method removes the ventricular component present in the unipolar EGM signals compared to the ABS method. The phase mapping analysis on the RVC method presented lower error when comparing the annotated EGM cycles with the phase inversion intervals. In terms of performance ABS and RVC behave similarly, but the real-time capability of the latter justifies its preference over the offline implementations. In the clinical environment other online investigations, e.g., rotational activity assessment, dominant frequency or local activation time mapping, might benefit from the real-time potential of the proposed cancellation method.
Collapse
Affiliation(s)
- Gonzalo R Ríos-Muñoz
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,La Red de Terapia Celular (TerCel), Instituto de Salud Carlos III, Madrid, Spain.,Departamento de Cardiología, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid, Spain
| | - Antonio Artés-Rodríguez
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Departamento de Teoría de la Señal y Comunicaciones, Universidad Carlos III de Madrid, Madrid, Spain
| | - Francisco Fernández-Avilés
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,La Red de Terapia Celular (TerCel), Instituto de Salud Carlos III, Madrid, Spain.,Departamento de Cardiología, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,Center for Biomedical Research in Cardiovascular Disease Network (CIBERCV), Madrid, Spain.,Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Ángel Arenal
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,La Red de Terapia Celular (TerCel), Instituto de Salud Carlos III, Madrid, Spain.,Center for Biomedical Research in Cardiovascular Disease Network (CIBERCV), Madrid, Spain
| |
Collapse
|
7
|
Pollnow S, Schwaderlapp G, Loewe A, Dössel O. Monitoring the dynamics of acute radiofrequency ablation lesion formation in thin-walled atria - a simultaneous optical and electrical mapping study. BIOMED ENG-BIOMED TE 2020; 65:327-341. [PMID: 31756159 DOI: 10.1515/bmt-2019-0013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 09/27/2019] [Indexed: 11/15/2022]
Abstract
Background Radiofrequency ablation (RFA) is a common approach to treat cardiac arrhythmias. During this intervention, numerous strategies are applied to indirectly estimate lesion formation. However, the assessment of the spatial extent of these acute injuries needs to be improved in order to create well-defined and durable ablation lesions. Methods We investigated the electrophysiological characteristics of rat atrial myocardium during an ex vivo RFA procedure with fluorescence-optical and electrical mapping. By analyzing optical data, the temporal growth of punctiform ablation lesions was reconstructed after stepwise RFA sequences. Unipolar electrograms (EGMs) were simultaneously recorded by a multielectrode array (MEA) before and after each RFA sequence. Based on the optical results, we searched for electrical features to delineate these lesions from healthy myocardium. Results Several unipolar EGM parameters were monotonically decreasing when distances between the electrode and lesion boundary were smaller than 2 mm. The negative component of the unipolar EGM [negative peak amplitude (Aneg)] vanished for distances lesser than 0.4 mm to the lesion boundary. Median peak-to-peak amplitude (Vpp) was decreased by 75% compared to baseline. Conclusion Aneg and Vpp are excellent parameters to discriminate the growing lesion area from healthy myocardium. The experimental setup opens new opportunities to investigate EGM characteristics of more complex ablation lesions.
Collapse
Affiliation(s)
- Stefan Pollnow
- Karlsruhe Institute of Technology, Institute of Biomedical Engineering, Fritz-Haber-Weg 1, Karlsruhe 76131, Germany, Tel.: +49-721-608-42650, Fax: +49-721-608-42789
| | - Gerald Schwaderlapp
- Karlsruhe Institute of Technology, Institute of Biomedical Engineering, Fritz-Haber-Weg 1, Karlsruhe 76131, Germany
| | - Axel Loewe
- Karlsruhe Institute of Technology, Institute of Biomedical Engineering, Fritz-Haber-Weg 1, Karlsruhe 76131, Germany
| | - Olaf Dössel
- Karlsruhe Institute of Technology, Institute of Biomedical Engineering, Fritz-Haber-Weg 1, Karlsruhe 76131, Germany
| |
Collapse
|
8
|
Salinet JL, Masca N, Stafford PJ, Ng GA, Schlindwein FS. Three-dimensional dominant frequency mapping using autoregressive spectral analysis of atrial electrograms of patients in persistent atrial fibrillation. Biomed Eng Online 2016; 15:28. [PMID: 26953240 PMCID: PMC4782578 DOI: 10.1186/s12938-016-0143-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 02/22/2016] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Areas with high frequency activity within the atrium are thought to be 'drivers' of the rhythm in patients with atrial fibrillation (AF) and ablation of these areas seems to be an effective therapy in eliminating DF gradient and restoring sinus rhythm. Clinical groups have applied the traditional FFT-based approach to generate the three-dimensional dominant frequency (3D DF) maps during electrophysiology (EP) procedures but literature is restricted on using alternative spectral estimation techniques that can have a better frequency resolution that FFT-based spectral estimation. METHODS Autoregressive (AR) model-based spectral estimation techniques, with emphasis on selection of appropriate sampling rate and AR model order, were implemented to generate high-density 3D DF maps of atrial electrograms (AEGs) in persistent atrial fibrillation (persAF). For each patient, 2048 simultaneous AEGs were recorded for 20.478 s-long segments in the left atrium (LA) and exported for analysis, together with their anatomical locations. After the DFs were identified using AR-based spectral estimation, they were colour coded to produce sequential 3D DF maps. These maps were systematically compared with maps found using the Fourier-based approach. RESULTS 3D DF maps can be obtained using AR-based spectral estimation after AEGs downsampling (DS) and the resulting maps are very similar to those obtained using FFT-based spectral estimation (mean 90.23 %). There were no significant differences between AR techniques (p = 0.62). The processing time for AR-based approach was considerably shorter (from 5.44 to 5.05 s) when lower sampling frequencies and model order values were used. Higher levels of DS presented higher rates of DF agreement (sampling frequency of 37.5 Hz). CONCLUSION We have demonstrated the feasibility of using AR spectral estimation methods for producing 3D DF maps and characterised their differences to the maps produced using the FFT technique, offering an alternative approach for 3D DF computation in human persAF studies.
Collapse
Affiliation(s)
- João L Salinet
- Biomedical Engineering, Modelling and Applied Social Sciences Centre, Federal ABC University, Bloco Delta, Sala 335 - Rua Arcturus, 03 - Jardim Antares, São Bernardo do Campo, SP, CEP 09606-070, Brazil.
- Department of Engineering, University of Leicester, Leicester, UK.
| | - Nicholas Masca
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK.
| | - Peter J Stafford
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK.
- Leicester NIHR Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, UK.
| | - G André Ng
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, UK.
- Leicester NIHR Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, UK.
| | - Fernando S Schlindwein
- Department of Engineering, University of Leicester, Leicester, UK.
- Leicester NIHR Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, UK.
| |
Collapse
|