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Wakamatsu Y, Nagashima K, Watanabe R, Hirata S, Hirata M, Okumura Y. Beyond the Lens: Unveiling the invisible atrioventricular node in the era of high-density mapping. J Cardiol 2024:S0914-5087(24)00099-6. [PMID: 38834137 DOI: 10.1016/j.jjcc.2024.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 05/21/2024] [Accepted: 05/29/2024] [Indexed: 06/06/2024]
Abstract
Numerous studies have clarified the histological characteristics of the area surrounding the atrioventricular (AV) node, commonly referred to as the triangle of Koch (ToK). Although it is suggested that the conduction of electric impulses from the atria to the ventricles via the AV node involves myocytes possessing distinct conduction properties and gap junction proteins, a comprehensive understanding of this complex conduction has not been fully established. Moreover, although various pathways have been proposed for both anterograde and retrograde conduction during atrioventricular nodal reentrant tachycardia (AVNRT), the reentrant circuits of AVNRT are not fully elucidated. Therefore, the slow pathway ablation for AVNRT has been conventionally performed, targeting both its anatomical location and slow pathway potential obtained during sinus rhythm. Recently, advancements in high-density three-dimensional (3D) mapping systems have facilitated the acquisition of more detailed electrophysiological potentials within the ToK. Several studies have indicated that the activation pattern, the low-voltage area within the ToK obtained during sinus rhythm, and the fractionated potentials acquired during tachycardia may be optimal targets for slow pathway ablation. This review provides an overview of the tissue surrounding the AV node as reported to date and summarizes the current understanding of AV conduction and AVNRT circuits. Furthermore, we discuss recent findings on slow pathway ablation utilizing high-density 3D mapping systems, exploring strategies for optimal slow pathway ablation.
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Affiliation(s)
- Yuji Wakamatsu
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Koichi Nagashima
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
| | - Ryuta Watanabe
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Shu Hirata
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Moyuru Hirata
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Yasuo Okumura
- Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
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Suzuki K, Aoki K, Sato E, Yamashina Y, Ishida A, Yagi T. Narrow QRS tachycardia in a patient with recurrence years after "rightward inferior extension" ablation: What is the mechanism? Pacing Clin Electrophysiol 2024. [PMID: 38761057 DOI: 10.1111/pace.15002] [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: 04/11/2024] [Revised: 05/02/2024] [Accepted: 05/09/2024] [Indexed: 05/20/2024]
Affiliation(s)
- Keisuke Suzuki
- Department of Cardiovascular Medicine, Sendai City Hospital, Sendai, Japan
| | - Kosuke Aoki
- Department of Cardiovascular Medicine, Sendai City Hospital, Sendai, Japan
| | - Eiji Sato
- Department of Cardiovascular Medicine, Sendai City Hospital, Sendai, Japan
| | | | - Akihiko Ishida
- Department of Cardiovascular Medicine, Sendai City Hospital, Sendai, Japan
| | - Tetsuo Yagi
- Department of Cardiovascular Medicine, Sendai City Hospital, Sendai, Japan
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Plappert F, Engström G, Platonov PG, Wallman M, Sandberg F. ECG-based estimation of respiration-induced autonomic modulation of AV nodal conduction during atrial fibrillation. Front Physiol 2024; 15:1281343. [PMID: 38779321 PMCID: PMC11110927 DOI: 10.3389/fphys.2024.1281343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 04/08/2024] [Indexed: 05/25/2024] Open
Abstract
Introduction: Information about autonomic nervous system (ANS) activity may offer insights about atrial fibrillation (AF) progression and support personalized AF treatment but is not easily accessible from the ECG. In this study, we propose a new approach for ECG-based assessment of respiratory modulation in atrioventricular (AV) nodal refractory period and conduction delay. Methods: A 1-dimensional convolutional neural network (1D-CNN) was trained to estimate respiratory modulation of AV nodal conduction properties from 1-minute segments of RR series, respiration signals, and atrial fibrillatory rates (AFR) using synthetic data that replicates clinical ECG-derived data. The synthetic data were generated using a network model of the AV node and 4 million unique model parameter sets. The 1D-CNN was then used to analyze respiratory modulation in clinical deep breathing test data of 28 patients in AF, where an ECG-derived respiration signal was extracted using a novel approach based on periodic component analysis. Results: We demonstrated using synthetic data that the 1D-CNN can estimate the respiratory modulation from RR series alone with a Pearson sample correlation of r = 0.805 and that the addition of either respiration signal (r = 0.830), AFR (r = 0.837), or both (r = 0.855) improves the estimation. Discussion: Initial results from analysis of ECG data suggest that our proposed estimate of respiration-induced autonomic modulation, a resp, is reproducible and sufficiently sensitive to monitor changes and detect individual differences. However, further studies are needed to verify the reproducibility, sensitivity, and clinical significance of a resp.
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Affiliation(s)
- Felix Plappert
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Gunnar Engström
- Department of Clinical Sciences, Cardiovascular Research–Epidemiology, Malmö, Sweden
| | - Pyotr G. Platonov
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| | - Mikael Wallman
- Fraunhofer-Chalmers Centre, Department of Systems and Data Analysis, Gothenburg, Sweden
| | - Frida Sandberg
- Department of Biomedical Engineering, Lund University, Lund, Sweden
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Pandozi C, Botto GL, Loricchio ML, D'Ammando M, Lavalle C, Del Giorno G, Matteucci A, Mariani MV, Nicolis D, Segreti L, Papa AA, Casale MC, Galeazzi M, Russo M, Di Belardino N, Pelargonio G, Centurion Aznaran C, Malacrida M, Maddaluno F, Treglia S, Piccolo F, Colivicchi F. High-density mapping of Koch's triangle during sinus rhythm and typical atrioventricular nodal re-entrant tachycardia, integrated with direct recording of atrio-ventricular node structure potential. J Cardiovasc Electrophysiol 2024; 35:379-388. [PMID: 38185855 DOI: 10.1111/jce.16168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/11/2023] [Accepted: 12/15/2023] [Indexed: 01/09/2024]
Abstract
BACKGROUND The mechanism of typical slow-fast atrioventricular nodal re-entrant tachycardia (AVNRT) and its anatomical and electrophysiological circuit inside the right atrium (RA) and Koch's Triangle (KT) are not well known. OBJECTIVE To identify the potentials of the compact AV node and inferior extensions and to perform accurate mapping of the RA and KT in sinus rhythm (SR) and during AVNRT, to define the tachycardia circuit. METHODS Consecutive patients with typical AVNRT were enrolled in 12 Italian centers and underwent mapping and ablation by means of a basket catheter with small electrode spacing for ultrahigh-density mapping and a modified signal-filtering toolset to record the potentials of the AV nodal structures. RESULTS Forty-five consecutive cases of successful ablation of typical slow-fast AVNRT were included. The mean SR cycle length (CL) was 784.1 ± 6 ms and the mean tachycardia CL was 361.2 ± 54 ms. The AV node potential had a significantly shorter duration and higher amplitude in sinus rhythm than during tachycardia (60 ± 40 ms vs. 160 ± 40 ms, p < .001 and 0.3 ± 0.2 mV vs. 0.09 ± 0.12 mV, p < .001, respectively). The nodal potential duration extension was 169.4 ± 31 ms, resulting in a time-window coverage of 47.6 ± 9%. The recording of AV nodal structure potentials enabled us to obtain 100% coverage of the tachycardia CL during slow-fast AVNRT. CONCLUSION Detailed recording of the potentials of nodal structures is possible by means of multipolar catheters for ultrahigh-density mapping, allowing 100% of the AVNRT CL to be covered. These results also have clinical implications for the ablation of right-septal and para-septal arrhythmias.
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Affiliation(s)
- Claudio Pandozi
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | | | | | | | - Carlo Lavalle
- Azienda ospedaliero-universitaria Policlinico Umberto I, Rome, Italy
| | | | - Andrea Matteucci
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
- Department of System and Experimental Medicine, University of Rome 'Tor Vergata, Rome, Italy
| | | | | | | | - Andrea Antonio Papa
- Cardiology and Syncope Unit, Department of Medical Translational Sciences, University of Campania "Luigi Vanvitelli"-Monaldi Hospital, Naples, Italy
| | | | - Marco Galeazzi
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | - Maurizio Russo
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | | | - Gemma Pelargonio
- Istituto di Cardiologia Università Cattolica del Sacro Cuore, Rome, Italy
- Department of Cardiovascular Sciences, Arrhythmology Unit, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy
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Karlsson M, Platonov PG, Ulimoen SR, Sandberg F, Wallman M. Model-based estimation of AV-nodal refractory period and conduction delay trends from ECG. Front Physiol 2024; 14:1287365. [PMID: 38283279 PMCID: PMC10811553 DOI: 10.3389/fphys.2023.1287365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 12/18/2023] [Indexed: 01/30/2024] Open
Abstract
Introduction: Atrial fibrillation (AF) is the most common arrhythmia, associated with significant burdens to patients and the healthcare system. The atrioventricular (AV) node plays a vital role in regulating heart rate during AF by filtering electrical impulses from the atria. However, it is often insufficient in regards to maintaining a healthy heart rate, thus the AV node properties are modified using rate-control drugs. Moreover, treatment selection during permanent AF is currently done empirically. Quantifying individual differences in diurnal and short-term variability of AV-nodal function could aid in personalized treatment selection. Methods: This study presents a novel methodology for estimating the refractory period (RP) and conduction delay (CD) trends, and their uncertainty in the two pathways of the AV node during 24 h using non-invasive data. This was achieved by utilizing a network model together with a problem-specific genetic algorithm and an approximate Bayesian computation algorithm. Diurnal variability in the estimated RP and CD was quantified by the difference between the daytime and nighttime estimates, and short-term variability was quantified by the Kolmogorov-Smirnov distance between adjacent 10-min segments in the 24-h trends. Additionally, the predictive value of the derived parameter trends regarding drug outcome was investigated using several machine learning tools. Results: Holter electrocardiograms from 51 patients with permanent AF during baseline were analyzed, and the predictive power of variations in RP and CD on the resulting heart rate reduction after treatment with four rate control drugs was investigated. Diurnal variability yielded no correlation to treatment outcome, and no prediction of drug outcome was possible using the machine learning tools. However, a correlation between the short-term variability for the RP and CD in the fast pathway and resulting heart rate reduction during treatment with metoprolol (ρ = 0.48, p < 0.005 in RP, ρ = 0.35, p < 0.05 in CD) were found. Discussion: The proposed methodology enables non-invasive estimation of the AV node properties during 24 h, which-indicated by the correlation between the short-term variability and heart rate reduction-may have the potential to assist in treatment selection.
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Affiliation(s)
- Mattias Karlsson
- Department of Systems and Data Analysis, Fraunhofer-Chalmers Centre, Gothenburg, Sweden
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Pyotr G. Platonov
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| | - Sara R. Ulimoen
- Department of Medical Research, Vestre Viken Hospital Trust, Bærum Hospital, Drammen, Norway
| | - Frida Sandberg
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Mikael Wallman
- Department of Systems and Data Analysis, Fraunhofer-Chalmers Centre, Gothenburg, Sweden
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Ryzhii M, Ryzhii E. A compact multi-functional model of the rabbit atrioventricular node with dual pathways. Front Physiol 2023; 14:1126648. [PMID: 36969598 PMCID: PMC10036810 DOI: 10.3389/fphys.2023.1126648] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 02/22/2023] [Indexed: 03/12/2023] Open
Abstract
The atrioventricular node (AVN) is considered a “black box”, and the functioning of its dual pathways remains controversial and not fully understood. In contrast to numerous clinical studies, there are only a few mathematical models of the node. In this paper, we present a compact, computationally lightweight multi-functional rabbit AVN model based on the Aliev-Panfilov two-variable cardiac cell model. The one-dimensional AVN model includes fast (FP) and slow (SP) pathways, primary pacemaking in the sinoatrial node, and subsidiary pacemaking in the SP. To obtain the direction-dependent conduction properties of the AVN, together with gradients of intercellular coupling and cell refractoriness, we implemented the asymmetry of coupling between model cells. We hypothesized that the asymmetry can reflect some effects related to the complexity of the real 3D structure of AVN. In addition, the model is accompanied by a visualization of electrical conduction in the AVN, revealing the interaction between SP and FP in the form of ladder diagrams. The AVN model demonstrates broad functionality, including normal sinus rhythm, AVN automaticity, filtering of high-rate atrial rhythms during atrial fibrillation and atrial flutter with Wenckebach periodicity, direction-dependent properties, and realistic anterograde and retrograde conduction curves in the control case and the cases of FP and SP ablation. To show the validity of the proposed model, we compare the simulation results with the available experimental data. Despite its simplicity, the proposed model can be used both as a stand-alone module and as a part of complex three-dimensional atrial or whole heart simulation systems, and can help to understand some puzzling functions of AVN.
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Affiliation(s)
- Maxim Ryzhii
- Department of Computer Science and Engineering, University of Aizu, Aizu-Wakamatsu, Japan
- *Correspondence: Maxim Ryzhii ,
| | - Elena Ryzhii
- Department of Anatomy and Histology, Fukushima Medical University, Fukushima, Japan
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Pandozi C, Matteucci A, Galeazzi M, Russo M, Lavalle C, Ficili S, Malacrida M, Colivicchi F. New insights into atrioventricular nodal anatomy, physiology, and immunochemistry: A comprehensive review and a proposed model of the slow-fast atrioventricular nodal reentrant tachycardia circuit in agreement with direct potential recordings in the Koch's triangle area. Heart Rhythm 2023; 20:614-626. [PMID: 36634901 DOI: 10.1016/j.hrthm.2023.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 01/04/2023] [Accepted: 01/04/2023] [Indexed: 01/11/2023]
Abstract
Atrioventricular nodal reentrant tachycardia (AVNRT) is the most frequent regular tachycardia in humans. In this review, we describe the most recent discoveries regarding the anatomical, physiological, and molecular biological features of the atrioventricular junction that could underlie the typical slow-fast AVNRT mechanisms, as these insights could lead to the proposal of a new theory concerning the circuit of this arrhythmia. Despite several models have been proposed over the years, the precise anatomical site of the reentrant circuit and the pathway involved in the slow-fast AVNRT have not been conclusively defined. One possible way to evaluate all the hypotheses regarding the nodal tachycardia circuit in humans is to map this circuit. Thus, we tried to identify the slow potential of nodal and inferior extension structures by using automated mapping of atrial activation during both sinus rhythm and typical slow-fast AVNRT. This constitutes a first step toward the definition of nodal area activation in sinus rhythm and during slow-fast AVNRT. Further studies and technical improvements in recording the potentials of the atrioventricular node structures are necessary to confirm our initial results.
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Affiliation(s)
- Claudio Pandozi
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy.
| | | | - Marco Galeazzi
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | - Maurizio Russo
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | - Carlo Lavalle
- Department of Cardiovascular, Respiratory, Nephrological, Anesthesiological and Geriatric Sciences, "Sapienza" University of Rome, Rome, Italy
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Trifunović-Zamaklar D, Jovanović I, Vratonjić J, Petrović O, Paunović I, Tešić M, Boričić-Kostić M, Ivanović B. The basic heart anatomy and physiology from the cardiologist's perspective: Toward a better understanding of left ventricular mechanics, systolic, and diastolic function. JOURNAL OF CLINICAL ULTRASOUND : JCU 2022; 50:1026-1040. [PMID: 36218206 DOI: 10.1002/jcu.23316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 06/16/2023]
Abstract
A comprehensive understanding of the cardiac structure-function relationship is essential for proper clinical cardiac imaging. This review summarizes the basic heart anatomy and physiology from the perspective of a heart imager focused on myocardial mechanics. The main issues analyzed are the left ventricular (LV) architecture, the LV myocardial deformation through the cardiac cycle, the LV diastolic function basic parameters and the basic parameters of the LV deformation used in clinical practice for the LV function assessment.
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Affiliation(s)
- Danijela Trifunović-Zamaklar
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
- School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivana Jovanović
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
| | - Jelena Vratonjić
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
| | - Olga Petrović
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
- School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivana Paunović
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
| | - Milorad Tešić
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
- School of Medicine, University of Belgrade, Belgrade, Serbia
| | | | - Branislava Ivanović
- Clinic for Cardiology, University Clinical Center of Serbia, Belgrade, Serbia
- School of Medicine, University of Belgrade, Belgrade, Serbia
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9
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Plappert F, Wallman M, Abdollahpur M, Platonov PG, Östenson S, Sandberg F. An atrioventricular node model incorporating autonomic tone. Front Physiol 2022; 13:976468. [PMID: 36187793 PMCID: PMC9520409 DOI: 10.3389/fphys.2022.976468] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/10/2022] [Indexed: 11/19/2022] Open
Abstract
The response to atrial fibrillation (AF) treatment is differing widely among patients, and a better understanding of the factors that contribute to these differences is needed. One important factor may be differences in the autonomic nervous system (ANS) activity. The atrioventricular (AV) node plays an important role during AF in modulating heart rate. To study the effect of the ANS-induced activity on the AV nodal function in AF, mathematical modelling is a valuable tool. In this study, we present an extended AV node model that incorporates changes in autonomic tone. The extension was guided by a distribution-based sensitivity analysis and incorporates the ANS-induced changes in the refractoriness and conduction delay. Simulated RR series from the extended model driven by atrial impulse series obtained from clinical tilt test data were qualitatively evaluated against clinical RR series in terms of heart rate, RR series variability and RR series irregularity. The changes to the RR series characteristics during head-down tilt were replicated by a 10% decrease in conduction delay, while the changes during head-up tilt were replicated by a 5% decrease in the refractory period and a 10% decrease in the conduction delay. We demonstrate that the model extension is needed to replicate ANS-induced changes during tilt, indicating that the changes in RR series characteristics could not be explained by changes in atrial activity alone.
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Affiliation(s)
- Felix Plappert
- Department of Biomedical Engineering, Lund University, Lund, Sweden
- *Correspondence: Felix Plappert,
| | - Mikael Wallman
- Department of Systems and Data Analysis, Fraunhofer-Chalmers Centre, Gothenburg, Sweden
| | | | - Pyotr G. Platonov
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| | - Sten Östenson
- Department of Internal Medicine and Department of Clinical Physiology, Central Hospital Kristianstad, Kristianstad, Sweden
| | - Frida Sandberg
- Department of Biomedical Engineering, Lund University, Lund, Sweden
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10
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Impact of common rhythm disturbances on echocardiographic measurements and interpretation. Clin Res Cardiol 2022; 111:1301-1312. [DOI: 10.1007/s00392-022-02096-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 08/30/2022] [Indexed: 01/18/2023]
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Mantri S, Wu SM, Goodyer WR. Molecular Profiling of the Cardiac Conduction System: the Dawn of a New Era. Curr Cardiol Rep 2021; 23:103. [PMID: 34196831 DOI: 10.1007/s11886-021-01536-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW Recent technological advances have led to an increased ability to define the gene expression profile of the cardiac conduction system (CCS). Here, we review the most salient studies to emerge in recent years and discuss existing gaps in our knowledge as well as future areas of investigation. RECENT FINDINGS Molecular profiling of the CCS spans several decades. However, the advent of high-throughput sequencing strategies has allowed for the discovery of unique transcriptional programs of the many diverse CCS cell types. The CCS, a diverse structure with significant inter- and intra-component cellular heterogeneity, is essential to the normal function of the heart. Progress in transcriptomic profiling has improved the resolution and depth of characterization of these unique and clinically relevant CCS cell types. Future studies leveraging this big data will play a crucial role in improving our understanding of CCS development and function as well as translating these findings into tangible translational tools for the improved detection, prevention, and treatment of cardiac arrhythmias.
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Affiliation(s)
- Sruthi Mantri
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Sean M Wu
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA.,Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Stanford, CA, 94305, USA.,Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - William R Goodyer
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA. .,Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Stanford, CA, 94305, USA. .,Division of Pediatric Cardiology, Electrophysiology, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford University School of Medicine, Room G1105 Lokey Stem Cell Research Building, 265 Campus Drive, Stanford, CA, 94305, USA.
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12
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The sensitivity of graphic trends in differentiating sinus and supraventricular tachycardia. J Electrocardiol 2021; 66:98-100. [PMID: 33887554 DOI: 10.1016/j.jelectrocard.2021.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/31/2021] [Accepted: 04/04/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND The use of cardiac telemetry in the inpatient setting is widespread and has become integral in managing hospitalized patients. Telemetry is used to monitor patients with brady- and tachyarrhythmias. While most of the focus is on the rhythm strip data, a significant utility remains in analyzing the graphic heart rate trends. We specifically focused on the shape of the curve (rectangle or bell) of the heart rate over time to differentiate sinus tachycardia (ST) and supraventricular tachycardia (SVT). We hypothesized that identifying the shape of the graphic trend would improve the accuracy of diagnosis. METHODS To demonstrate the simplicity of employing this method for improving the diagnosis of arrhythmia, we had senior medical students evaluate the telemetry strips and graphical trends. We gathered data from the medical student interpretation of 82 strips of in-hospital cardiac telemetry and asked them to differentiate ST and SVT based on the shape of the graphic trend. Each rhythm strip and the graphic trend was interpreted by two clinical cardiac electrophysiology attending physicians and confirmed on a 12‑lead electrocardiogram. RESULTS When students were asked to choose between ST and SVT based on the telemetry rhythm strip without graphic trends, 73% of their answers were correct. Diagnostic accuracy improved to 96% correct with the addition of the graphic trend. Depending on the telemetry rhythm strip alone, sensitivity to detect SVT was 75%, with 68% specificity. With the addition of the graphical trend, sensitivity improved to 98% and specificity 100%. CONCLUSION Review of graphical trends, specifically the analysis of onset and offset, allows novice ECG readers to improve the ability to distinguish between ST and SVT.
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Hassinen M, Dzhumaniiazova I, Abramochkin DV, Vornanen M. Ionic basis of atrioventricular conduction: ion channel expression and sarcolemmal ion currents of the atrioventricular canal of the rainbow trout (Oncorhynchus mykiss) heart. J Comp Physiol B 2021; 191:327-346. [PMID: 33575867 PMCID: PMC7895799 DOI: 10.1007/s00360-021-01344-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 12/15/2020] [Accepted: 01/18/2021] [Indexed: 12/17/2022]
Abstract
Atrioventricular (AV) nodal tissue synchronizes activities of atria and ventricles of the vertebrate heart and is also a potential site of cardiac arrhythmia, e.g., under acute heat stress. Since ion channel composition and ion currents of the fish AV canal have not been previously studied, we measured major cation currents and transcript expression of ion channels in rainbow trout (Oncorhynchus mykiss) AV tissue. Both ion current densities and expression of ion channel transcripts indicate that the fish AV canal has a characteristic electrophysiological phenotype that differs from those of sinoatrial tissue, atrium and ventricle. Two types of cardiomyocytes were distinguished electrophysiologically in trout AV nodal tissue: the one (transitional cell) is functionally intermediate between working atrial/ventricular myocytes and the other (AV nodal cell) has a less negative resting membrane potential than atrial and ventricular myocytes and is a more similar to the sinoatrial nodal cells in ion channel composition. The AV nodal cells are characterized by a small or non-existent inward rectifier potassium current (IK1), low density of fast sodium current (INa) and relatively high expression of T-type calcium channels (CACNA3.1). Pacemaker channel (HCN4 and HCN2) transcripts were expressed in the AV nodal tissue but If current was not found in enzymatically isolated nodal myocytes. The electrophysiological properties of the rainbow trout nodal cells are appropriate for a slow rate of action potential conduction (small INa) and a moderate propensity for pacemaking activity (absence of IK1).
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Affiliation(s)
- Minna Hassinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, 80101, Joensuu, Finland
| | - Irina Dzhumaniiazova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Denis V Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.,Laboratory of Cardiac Electrophysiology, National Medical Research Center for Cardiology, Moscow, Russia.,Department of Physiology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Matti Vornanen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, 80101, Joensuu, Finland.
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Tobiume T, Kato R, Matsuura T, Matsumoto K, Hara M, Takamori N, Taketani Y, Okawa K, Ise T, Kusunose K, Yamaguchi K, Yagi S, Fukuda D, Yamada H, Wakatsuki T, Soeki T, Sata M, Matsumoto K. Antegrade slow pathway mapping of typical atrioventricular nodal reentrant tachycardia based on direct slow pathway capture. J Arrhythm 2021; 37:128-139. [PMID: 33664895 PMCID: PMC7896471 DOI: 10.1002/joa3.12484] [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: 06/17/2020] [Revised: 11/14/2020] [Accepted: 11/30/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Radiofrequency (RF) ablation of typical atrioventricular nodal reentrant tachycardia (tAVNRT) is performed without revealing out the location of antegrade slow pathway (ASp). In this study, we studied a new electrophysiological method of identifying the site of ASp. METHODS This study included 19 patients. Repeated series of very high-output single extrastimulations (VhoSESts) were delivered at the anatomical slow pathway region during tAVNRT. Tachycardia cycle length (TCL), coupling interval (CI), and return cycle (RC) were measured and the prematurity of VhoSESts [ΔPM (= TCL - CI)] and the prolongation of RCs [ΔPL (= RC - TCL)] were calculated. Pacing sites were classified into two categories: (i) ASp capture sites [DSPC(+) sites], where two different RCs were shown, and ASp non-capture sites [DSPC(-) sites], where only one RC was shown. RF ablation was performed at DSPC(+) sites and/or sites with catheter-induced mechanical trauma (CIMT) to ASp. RESULTS DSPC(+) sites were shown in 13 patients (68%). RF ablation was successful in all patients without any degree of atrioventricular block nor recurrence. Total number of RF applications was 1.8 ± 1.1. Minimal distance between successful ablation sites and DSPC(+)/CIMT sites and His bundle (HB) electrogram recording sites was 1.9 ± 0.8 mm and 19.8 ± 6.1 mm, respectively. ΔPL of more than 92.5 ms, ΔPL/TCL of more than 0.286, and ΔPL/ΔPM of more than 1.565 could identify ASp with sensitivity of 100%, 91.1%, and 88.9% and specificity of 92.9%, 97.0%, and 97.6%, respectively. CONCLUSIONS Sites with ASp capture and CIMT were close to successful ablation sites and could be useful indicators of tAVNRT ablation.
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Affiliation(s)
- Takeshi Tobiume
- Department of CardiologyTokushima University HospitalTokushimaJapan
- Department of CardiologySaitama Medical University International Medical CenterHidakaJapan
- Department of CardiologyKawashima HospitalTokushimaJapan
- Department of CardiologyShikoku Medical Center for Children and AdultsZentsujiJapan
| | - Ritsushi Kato
- Department of CardiologySaitama Medical University International Medical CenterHidakaJapan
| | - Tomomi Matsuura
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | | | - Motoki Hara
- Hara Clinic Higashi‐HiroshimaHigashi‐HiroshimaJapan
| | | | - Yoshio Taketani
- Department of CardiologyShikoku Medical Center for Children and AdultsZentsujiJapan
| | - Keisuke Okawa
- Department of CardiologyKagawa Prefectural Central HospitalTakamatsuJapan
| | - Takayuki Ise
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Kenya Kusunose
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Koji Yamaguchi
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Shusuke Yagi
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Daijyu Fukuda
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Hirotsugu Yamada
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | | | - Takeshi Soeki
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Masataka Sata
- Department of CardiologyTokushima University HospitalTokushimaJapan
| | - Kazuo Matsumoto
- Department of CardiologySaitama Medical University International Medical CenterHidakaJapan
- Department of Internal MedicineHigashi‐Matsuyama Medical Association HospitalHigashimatsuyamaJapan
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Left sided ablation for Atrioventricular Nodal Re-entrant Tachycardia: Frequency, Characteristics and Outcomes. Indian Pacing Electrophysiol J 2020; 21:5-10. [PMID: 33129971 PMCID: PMC7854377 DOI: 10.1016/j.ipej.2020.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 10/04/2020] [Accepted: 10/21/2020] [Indexed: 11/24/2022] Open
Abstract
Background Left-sided ablation, targeting left inferior AV nodal extensions, is thought to be necessary for success in a small proportion of atrioventricular nodal re-entrant tachycardia (AVNRT) ablations; however Indian data are scarce in this regard. Methods Consecutive cases of AVNRT undergoing slow pathway ablation in a single centre over an 18-month period were retrospectively analyzed. Left-sided ablation at the posteroseptal mitral annulus was performed if right-sided ablation failed to abolish AVNRT. Results From January 2017 to June 2018, out of 215 consecutive supraventricular tachycardia (SVT) cases, 154 (71.6%) were AVNRT (47.1 ± 13.1 years, 46.1% male). Trans-septal ablation was required in 5 (3.2%) cases (mean age 48.8 ± 9.4 years; 4 female, 1 male); all with typical (slow-fast) form of AVNRT. Compared with cases needing only right-sided ablation, radiofrequency time (50.8 ± 16.9 vs. 9.9 ± 8.5 min; p = 0.005) and procedure time (166.0 ± 35.0 vs 79.6 ± 35.9 min; p = 0.004) were significantly longer for trans-septal cases, while baseline intervals and tachycardia cycle length were not significantly different. Junctional ectopy was seen in only 2 of the 5 cases during left-sided ablation, but acute success (non-inducibility) was obtained in 3 cases. There were no instances of AV block. Over mean follow-up of 12.2 ± 4.0 months, clinical recurrence of AVNRT occurred in one case, while others remained arrhythmia-free without medication. Conclusion Left-sided ablation was required in a small proportion of AVNRT ablations. Trans-septal approach targeting the posteroseptal mitral annulus was safe and yielded good mid-term clinical success.
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