1
|
Tourni M, Han SJ, Weber R, Kucinski M, Wan EY, Biviano AB, Konofagou EE. Electromechanical Cycle Length Mapping for atrial arrhythmia detection and cardioversion success assessment. Comput Biol Med 2023; 163:107084. [PMID: 37302374 PMCID: PMC10527498 DOI: 10.1016/j.compbiomed.2023.107084] [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: 12/05/2022] [Revised: 04/26/2023] [Accepted: 05/27/2023] [Indexed: 06/13/2023]
Abstract
BACKGROUND Direct current cardioversion (DCCV) is an established treatment to acutely convert atrial fibrillation (AF) to normal sinus rhythm. Yet, more than 70% of patients revert to AF shortly thereafter. Electromechanical Cycle Length Mapping (ECLM) is a high framerate, spectral analysis technique shown to non-invasively characterize electromechanical activation in paced canines and re-entrant flutter patients. This study assesses ECLM feasibility to map and quantify atrial arrhythmic electromechanical activation rates and inform on 1-day and 1-month DCCV response. METHODS Forty-five subjects (30 AF; 15 healthy sinus rhythm (SR) controls) underwent transthoracic ECLM in four standard apical 2D echocardiographic views. AF patients were imaged within 1 h pre- and post-DCCV. 3D-rendered atrial ECLM cycle length (CL) maps and spatial CL histograms were generated. CL dispersion and percentage of arrhythmic CLs≤333ms across the entire atrial myocardium were computed transmurally. ECLM results were subsequently used as indicators of DCCV success. RESULTS ECLM successfully confirmed the electrical atrial activation rates in 100% of healthy subjects (R2=0.96). In AF, ECLM maps localized the irregular activation rates pre-DCCV and confirmed successful post-DCCV with immediate reduction or elimination. ECLM metrics successfully distinguished DCCV 1-day and 1-month responders from non-responders, while pre-DCCV ECLM values independently predicted AF recurrence within 1-month post-DCCV. CONCLUSIONS ECLM can characterize electromechanical activation rates in AF, quantify their extent, and identify and predict short- and long-term AF recurrence. ELCM constitutes thus a noninvasive arrhythmia imaging modality that can aid clinicians in simultaneous AF severity quantification, prediction of AF DCCV response, and personalized treatment planning.
Collapse
Affiliation(s)
- Melina Tourni
- Depatrment of Biomedical Engineering, Columbia University, 630 W 168th Street, New York, 10032, NY, USA.
| | - Seungyeon Julia Han
- Depatrment of Biomedical Engineering, Columbia University, 630 W 168th Street, New York, 10032, NY, USA
| | - Rachel Weber
- Depatrment of Biomedical Engineering, Columbia University, 630 W 168th Street, New York, 10032, NY, USA
| | - Mary Kucinski
- Depatrment of Biomedical Engineering, Columbia University, 630 W 168th Street, New York, 10032, NY, USA
| | - Elaine Y Wan
- Department of Medicine and Vagelos College of Physicians and Surgeons, Columbia University, 630 W 168th Street, New York, 10032, NY, USA
| | - Angelo B Biviano
- Department of Medicine and Vagelos College of Physicians and Surgeons, Columbia University, 630 W 168th Street, New York, 10032, NY, USA
| | - Elisa E Konofagou
- Depatrment of Biomedical Engineering, Columbia University, 630 W 168th Street, New York, 10032, NY, USA; Department of Radiology, Columbia University, 630 W 168th Street, New York, 10032, NY, USA.
| |
Collapse
|
2
|
Agewall S, Tjessem LH, Rossignol P, Zannad F, Atar D, Lamiral Z, Machu JL, Dickstein K, Kjekshus J, von Lueder TG, Girerd N. Heart rate prediction of outcome in heart failure following myocardial infarction depend on heart rhythm status an analysis from the high-risk myocardial infarction database initiative. Int J Cardiol 2017; 249:274-281. [PMID: 28964557 DOI: 10.1016/j.ijcard.2017.09.182] [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: 01/24/2017] [Revised: 08/22/2017] [Accepted: 09/20/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Heart rate has been reported to be associated with adverse outcome in heart failure (HF) and myocardial infarction (MI), but conflicting evidence exists regarding its impact in patients with associated atrial fibrillation (AF). OBJECTIVES We investigated the differential impact of heart rate on clinical outcomes according to the presence or absence of AF in patients with reduced systolic function and/or HF after MI. METHODS We studied the association of heart rate with outcome using Cox-models in a merged dataset (n=28,771) of four randomized trials (CAPRICORN, EPHESUS, OPTIMAAL, and VALIANT). RESULTS At baseline, 3736 (13%) patients had AF. We identified a significant interaction between AF and heart rate, and a decreasing effect of heart rate with time, heart rate being less associated with outcome after 1year of follow-up (both p for interaction <0.001). We report associations with outcome separately in patients with and without AF. In addition, as neutral associations with outcome after 1year were estimated after adjustment on confounding factors, only association for the first year follow-up were provided. 10-bpm increase in heart rate conferred increased risk for all-cause mortality (1.27 [1.21 to 1.33], p<0.0001), CV-mortality (1.28 [1.22 to 1.34], p<0.0001), and HF-hospitalisation (1.25 [1.19 to 1.31], p<0.0001) in patients without AF. In contrast, in patients with AF, the incremental risk for 10-bpm increase in heart rate was attenuated for all-cause (1.14 [1.06 to 1.23], p=0.0007), CV-mortality (1.12 [1.03 to 1.22], p=0.006), and HF-hospitalisation (1.16 [1.07 to 1.26], p=0.0006, p for interaction with AF <0.001 for all outcomes). CONCLUSIONS In patients with reduced systolic function and/or HF post-MI, higher heart rate predicts increased major cardiovascular events during the first year following MI in patients without AF. This association is markedly attenuated in subjects with AF.
Collapse
Affiliation(s)
- Stefan Agewall
- Oslo University Hospital Ullevål, University of Oslo, Oslo, Norway; Institute of Clinical Sciences, University of Oslo, Oslo, Norway.
| | - Lars H Tjessem
- Oslo University Hospital Ullevål, University of Oslo, Oslo, Norway; Institute of Clinical Sciences, University of Oslo, Oslo, Norway
| | - Patrick Rossignol
- Inserm, Centre, d'Investigations Cliniques- 1433, and Inserm, U1116, Nancy, France; CHU Nancy, Institut Lorrain du Cœur et des Vaisseaux, Vandoeuvre lès Nancy, France; Université de Lorraine, Nancy, France; F-CRIN INI-CRCT (Cardiovascular and Renal Clinical Trialists) Network, Nancy, France
| | - Faiez Zannad
- Inserm, Centre, d'Investigations Cliniques- 1433, and Inserm, U1116, Nancy, France; CHU Nancy, Institut Lorrain du Cœur et des Vaisseaux, Vandoeuvre lès Nancy, France; Université de Lorraine, Nancy, France
| | - Dan Atar
- Oslo University Hospital Ullevål, University of Oslo, Oslo, Norway; Institute of Clinical Sciences, University of Oslo, Oslo, Norway
| | - Zohra Lamiral
- Inserm, Centre, d'Investigations Cliniques- 1433, and Inserm, U1116, Nancy, France; CHU Nancy, Institut Lorrain du Cœur et des Vaisseaux, Vandoeuvre lès Nancy, France; Université de Lorraine, Nancy, France; F-CRIN INI-CRCT (Cardiovascular and Renal Clinical Trialists) Network, Nancy, France
| | - Jean-Loup Machu
- Inserm, Centre, d'Investigations Cliniques- 1433, and Inserm, U1116, Nancy, France; CHU Nancy, Institut Lorrain du Cœur et des Vaisseaux, Vandoeuvre lès Nancy, France; Université de Lorraine, Nancy, France; F-CRIN INI-CRCT (Cardiovascular and Renal Clinical Trialists) Network, Nancy, France
| | - Kenneth Dickstein
- Stavanger University Hospital, Division of Cardiology, Stavanger, Norway
| | - John Kjekshus
- Oslo University Hospital Ullevål, University of Oslo, Oslo, Norway; Institute of Clinical Sciences, University of Oslo, Oslo, Norway
| | - Thomas G von Lueder
- Oslo University Hospital Ullevål, University of Oslo, Oslo, Norway; Institute of Clinical Sciences, University of Oslo, Oslo, Norway
| | - Nicolas Girerd
- Inserm, Centre, d'Investigations Cliniques- 1433, and Inserm, U1116, Nancy, France; CHU Nancy, Institut Lorrain du Cœur et des Vaisseaux, Vandoeuvre lès Nancy, France; Université de Lorraine, Nancy, France; F-CRIN INI-CRCT (Cardiovascular and Renal Clinical Trialists) Network, Nancy, France
| | | |
Collapse
|
3
|
Masè M, Disertori M, Marini M, Ravelli F. Characterization of rate and regularity of ventricular response during atrial tachyarrhythmias. Insight on atrial and nodal determinants. Physiol Meas 2017; 38:800-818. [DOI: 10.1088/1361-6579/aa6388] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
4
|
García M, Ródenas J, Alcaraz R, Rieta JJ. Application of the relative wavelet energy to heart rate independent detection of atrial fibrillation. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2016; 131:157-168. [PMID: 27265056 DOI: 10.1016/j.cmpb.2016.04.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 03/11/2016] [Accepted: 04/07/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND AND OBJECTIVES Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a growing healthcare burden worldwide. It is often asymptomatic and may appear as episodes of very short duration; hence, the development of methods for its automatic detection is a challenging requirement to achieve early diagnosis and treatment strategies. The present work introduces a novel method exploiting the relative wavelet energy (RWE) to automatically detect AF episodes of a wide variety in length. METHODS The proposed method analyzes the atrial activity of the surface electrocardiogram (ECG), i.e., the TQ interval, thus being independent on the ventricular activity. To improve its performance under noisy recordings, signal averaging techniques were applied. The method's performance has been tested with synthesized recordings under different AF variable conditions, such as the heart rate, its variability, the atrial activity amplitude or the presence of noise. Next, the method was tested with real ECG recordings. RESULTS Results proved that the RWE provided a robust automatic detection of AF under wide ranges of heart rates, atrial activity amplitudes as well as noisy recordings. Moreover, the method's detection delay proved to be shorter than most of previous works. A trade-off between detection delay and noise robustness was reached by averaging 15 TQ intervals. Under these conditions, AF was detected in less than 7 beats, with an accuracy higher than 90%, which is comparable to previous works. CONCLUSIONS Unlike most of previous works, which were mainly based on quantifying the irregular ventricular response during AF, the proposed metric presents two major advantages. First, it can perform successfully even under heart rates with no variability. Second, it consists of a single metric, thus turning its clinical interpretation and real-time implementation easier than previous methods requiring combined indices under complex classifiers.
Collapse
Affiliation(s)
- Manuel García
- Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, Albacete, Spain
| | - Juan Ródenas
- Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, Albacete, Spain
| | - Raúl Alcaraz
- Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, Albacete, Spain.
| | - José J Rieta
- Biomedical Synergy, Electronic Engineering Department, Universidad Politécnica de Valencia, Valencia, Spain
| |
Collapse
|
5
|
Zhang Y. His electrogram alternans (Zhang's phenomenon) and a new model of dual pathway atrioventricular node conduction. J Interv Card Electrophysiol 2015; 45:19-28. [PMID: 26614299 DOI: 10.1007/s10840-015-0079-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 11/19/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND In contrast to the current textbook model and the current clinical index of dual pathway atrioventricular (AV) nodal conduction, here we summarize the discovery and validation of Zhang's phenomenon (originally His electrogram alternans) as a new index of dual pathway conduction. We also describe the new findings of transverse-versus-longitudinal electrical propagation within the AV node as the electrophysiological basis underlining this new index. Thus, a new index and a new model of dual pathway AV conduction are being developed. METHODS We have reviewed current literature and provided evidence supporting a new index and a new model of dual pathway AV conduction. RESULTS Recent data revealed that during fast pathway conduction, electrical excitation in the AV node propagates in a superior to inferior direction across AV conduction axis and fiber orientation to reach first the superior His bundle fibers. However, this transverse conduction can fail easily within the superior nodal domain at fast rates. The failing of transverse propagation permits electrical excitation formed at the posterior/inferior nodal region to propagate longitudinally along fiber orientation in a posterior to anterior direction through the inferior nodal domain to reach the inferior His bundle (slow pathway conduction). This transverse-versus-longitudinal electrical propagation within the AV node results in a functional dissociation in the distal node and formation of dual inputs into the His bundle, providing the electrophysiological basis for the formation of Zhang's phenomenon (His electrogram alternans). CONCLUSIONS Based on strong experimental data, a new index and a new model of dual pathway AV nodal conduction are emerging, although they are still awaiting clinical validation.
Collapse
Affiliation(s)
- Youhua Zhang
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Room 208, Rockefeller Building, Northern Boulevard, P.O. Box 8000, Old Westbury, NY, 11568-8000, USA.
| |
Collapse
|
6
|
Wavelet Entropy Automatically Detects Episodes of Atrial Fibrillation from Single-Lead Electrocardiograms. ENTROPY 2015. [DOI: 10.3390/e17096179] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
7
|
Tondato F, Zeng H, Goodchild T, Ng FS, Chronos N, Peters NS. Autologous Dermal Fibroblast Injections Slow Atrioventricular Conduction and Ventricular Rate in Atrial Fibrillation in Swine. Circ Arrhythm Electrophysiol 2015; 8:439-46. [DOI: 10.1161/circep.114.001536] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 01/20/2015] [Indexed: 11/16/2022]
Abstract
Background—
Nonpharmacological ventricular rate control in atrial fibrillation (AF) without producing atrioventricular (AV) block remains a clinical challenge. We investigated the hypothesis that autologous dermal fibroblast (ADF) injection into the AV nodal area would reduce ventricular response during AF without causing AV block.
Methods and Results—
Fourteen pigs underwent electrophysiology study before, immediately, and 28 days after ≈200 million cultured ADFs (n=8) or saline (n=6) were injected under electroanatomical guidance in the AV nodal area, with continuous 28-day ECG recording. In the ADF group at 28 days postinjection, there were prolongations of PR interval (after versus before: 130±13 versus 113±14 ms,
P
=0.04), of AH interval during both sinus rhythm (92±13 versus 76.8±8 ms,
P
<0.01) and atrial pacing at 400 ms (102±13 versus 91±9 ms,
P
<0.01), and of AV node Wenckebach cycle length (230±19 versus 213±24 ms,
P
<0.01), with no changes in the control group. The RR interval during induced AF 28 days after injections was 24% longer in ADF-treated group compared with controls (488±120 versus 386±116 ms,
P
<0.001). Histological analysis revealed presence of ADF-labeled cells in the AV nodal area at 28 days. Transient accelerated junctional rhythm during injections, and transient nocturnal Mobitz I AV conduction occurred early postinjection in both groups.
Conclusions—
Cells survived for 4 weeks and significantly slowed AV conduction and ventricular rate in acutely induced AF. Critically, despite a large number of injections in the AV nodal area and marked effects on AV conduction, AV block did not occur. Further studies are necessary to determine the clinical feasibility and safety of this strategy for ventricular rate control in AF.
Collapse
Affiliation(s)
- Fernando Tondato
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| | - Hong Zeng
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| | - Traci Goodchild
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| | - Fu Siong Ng
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| | - Nicolas Chronos
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| | - Nicholas S. Peters
- From the Myocardial Function Section, Imperial College & Imperial NHS Trust, London, United Kingdom (F.T., N.S.P.); and Saint Joseph’s Translational Research Institute/Saint Joseph’s Hospital of Atlanta, GA (F.T., H.Z., T.G., F.S.N., N.C.)
| |
Collapse
|
8
|
Nonlinear synchronization assessment between atrial and ventricular activations series from the surface ECG in atrial fibrillation. Biomed Signal Process Control 2013. [DOI: 10.1016/j.bspc.2013.01.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
9
|
Masè M, Glass L, Disertori M, Ravelli F. The AV synchrogram: A novel approach to quantify atrioventricular coupling during atrial arrhythmias. Biomed Signal Process Control 2013. [DOI: 10.1016/j.bspc.2013.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
10
|
Chang GJ, Chang CJ, Chen WJ, Yeh YH, Lee HY. Electrophysiological and mechanical effects of caffeic acid phenethyl ester, a novel cardioprotective agent with antiarrhythmic activity, in guinea-pig heart. Eur J Pharmacol 2013; 702:194-207. [DOI: 10.1016/j.ejphar.2013.01.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 12/16/2012] [Accepted: 01/28/2013] [Indexed: 01/31/2023]
|
11
|
Abstract
BACKGROUND The atrioventricular node (AVN) plays a vital role in determining the ventricular rate during atrial fibrillation (AF). AF results in profound electrophysiological and structural remodeling in the atria as well as the sinus node. However, it is unknown whether AVN undergoes remodeling during AF. OBJECTIVE To determine whether AVN undergoes functional remodeling during AF. METHODS AVN conduction properties were studied in vitro in 9 rabbits with AF and 10 normal controls. A previously validated index of AVN dual-pathway electrophysiology, His-electrogram alternans, was used to monitor fast-pathway or slow-pathway (SP) AVN conduction in these experiments. AVN conduction properties were further studied in vivo in 7 dogs with chronic AF and 8 controls. RESULTS Compared with the control rabbits, the rabbits with AF had a longer AVN conduction time (83 ± 16 ms vs 68 ± 7 ms; P <.01), longer AVN effective refractory period (141 ± 27 ms vs 100 ± 9 ms; P <.01), an earlier transition from fast-pathway to SP conduction (at a longer prematurity, 249 ± 60 ms vs 171 ± 24 ms; P <.01), and a slower ventricular rate during simulated AF (RR interval 249 ± 42 ms vs 202 ± 12 ms; P <.01). Notably, a larger proportion of conducted beats utilized the SP in AF preparations (92% ± 12% vs 63% ± 32%; P <.05). Long-term AF in dogs resulted in a longer atrioventricular conduction time and AVN effective refractory period and a slower ventricular rate during AF compared with the controls. CONCLUSIONS Pronounced AVN functional electrophysiological remodeling occurs after long-term AF, which could lead to a spontaneous slowing of the ventricular rate. Furthermore, the SP dominance during AF underscores the effectiveness of its modification by ablation for ventricular rate control during AF.
Collapse
|
12
|
Khori V, Alizadeh AM, Yazdi H, Rakhshan E, Mirabbasi A, Changizi S, Mazandarani M, Nayebpour M. Frequency-dependent Electrophysiological Remodeling of the AV Node by Hydroalcohol Extract of Crocus sativus
L. (Saffron) During Experimental Atrial Fibrillation: The Role of Endogenous Nitric Oxide. Phytother Res 2011; 26:826-32. [DOI: 10.1002/ptr.3643] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 07/11/2011] [Accepted: 07/11/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Vahid Khori
- Golestan Cardiovascular Research Center; Golestan University of Medical Sciences; Gorgan Iran
| | | | - Hamidreza Yazdi
- Golestan Cardiovascular Research Center; Golestan University of Medical Sciences; Gorgan Iran
| | - Elnaz Rakhshan
- Golestan Cardiovascular Research Center; Golestan University of Medical Sciences; Gorgan Iran
| | - Abbas Mirabbasi
- Golestan Cardiovascular Research Center; Golestan University of Medical Sciences; Gorgan Iran
| | - Shima Changizi
- Golestan Cardiovascular Research Center; Golestan University of Medical Sciences; Gorgan Iran
| | | | - Mohsen Nayebpour
- Department of Pharmacology, Faculty of Pharmacy; Tehran University of Medical Sciences; Tehran Iran
| |
Collapse
|
13
|
Climent AM, Atienza F, Millet J, Guillem MS. Generation of realistic atrial to atrial interval series during atrial fibrillation. Med Biol Eng Comput 2011; 49:1261-8. [DOI: 10.1007/s11517-011-0823-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Accepted: 07/31/2011] [Indexed: 11/28/2022]
|
14
|
One-dimensional mathematical model of the atrioventricular node including atrio-nodal, nodal, and nodal-his cells. Biophys J 2010; 97:2117-27. [PMID: 19843444 DOI: 10.1016/j.bpj.2009.06.056] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 06/05/2009] [Accepted: 06/30/2009] [Indexed: 11/24/2022] Open
Abstract
Mathematical models are a repository of knowledge as well as research and teaching tools. Although action potential models have been developed for most regions of the heart, there is no model for the atrioventricular node (AVN). We have developed action potential models for single atrio-nodal, nodal, and nodal-His cells. The models have the same action potential shapes and refractoriness as observed in experiments. Using these models, together with models for the sinoatrial node (SAN) and atrial muscle, we have developed a one-dimensional (1D) multicellular model including the SAN and AVN. The multicellular model has slow and fast pathways into the AVN and using it we have analyzed the rich behavior of the AVN. Under normal conditions, action potentials were initiated in the SAN center and then propagated through the atrium and AVN. The relationship between the AVN conduction time and the timing of a premature stimulus (conduction curve) is consistent with experimental data. After premature stimulation, atrioventricular nodal reentry could occur. After slow pathway ablation or block of the L-type Ca(2+) current, atrioventricular nodal reentry was abolished. During atrial fibrillation, the AVN limited the number of action potentials transmitted to the ventricle. In the absence of SAN pacemaking, the inferior nodal extension acted as the pacemaker. In conclusion, we have developed what we believe is the first detailed mathematical model of the AVN and it shows the typical physiological and pathophysiological characteristics of the tissue. The model can be used as a tool to analyze the complex structure and behavior of the AVN.
Collapse
|
15
|
|
16
|
Climent AM, de la Salud Guillem M, Husser D, Castells F, Millet J, Bollmann A. PoincarÉ Surface Profiles of RR Intervals: A Novel Noninvasive Method for the Evaluation of Preferential AV Nodal Conduction During Atrial Fibrillation. IEEE Trans Biomed Eng 2009; 56:433-42. [DOI: 10.1109/tbme.2008.2003273] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
17
|
Mainardi L, Sörnmo L, Cerutti S. Understanding Atrial Fibrillation: The Signal Processing Contribution, Part II. ACTA ACUST UNITED AC 2008. [DOI: 10.2200/s00153ed1v01y200809bme025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
18
|
Lian J, Müssig D, Lang V. Ventricular rate smoothing for atrial fibrillation: a quantitative comparison study. ACTA ACUST UNITED AC 2007; 9:506-13. [PMID: 17507355 DOI: 10.1093/europace/eum088] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIMS To quantitatively compare the ventricular rate-smoothing (VRS) effects of different ventricular pacing (VP) protocols for atrial fibrillation (AF). METHODS AND RESULTS Using a recently developed open-source model that can simulate the ventricular response in AF and VP, the performance of fixed-rate pacing and four previously published VRS algorithms were assessed by the mean RR (mRR), the root mean square of successive RR differences (RMSSD), the percentage of ventricular senses (VS%), and the percentage of short RR intervals (sRR%). All pacing protocols cause rate-dependent reduction of RMSSD, VS%, and sRR% with or without shortening of mRR compared to spontaneous AF. Fixed-rate pacing was more sensitive to the intrinsic rate than the VRS algorithms. The performance was generally comparable between different VRS algorithms, although higher mRR and VS% can be achieved at the expense of larger RMSSD and sRR%. CONCLUSION The effect of VP on ventricular rhythm in AF depends on both intrinsic rate and the aggressiveness of the pacing protocol. Adequate rate control is necessary for effective operation of the VRS algorithm. Choosing VRS algorithm should balance between the beneficial effects of rate regularization and the negative effects of increasing heart rate and percentage of VP.
Collapse
Affiliation(s)
- Jie Lian
- Applied Clinical Research Department, Micro Systems Engineering, Inc., 6024 SW Jean Road, Lake Oswego, OR 97035, USA.
| | | | | |
Collapse
|
19
|
Zhang Y, Yamada H, Bibevski S, Zhuang S, Mowrey KA, Wallick DW, Oh S, Mazgalev TN. Chronic atrioventricular nodal vagal stimulation: first evidence for long-term ventricular rate control in canine atrial fibrillation model. Circulation 2005; 112:2904-11. [PMID: 16260638 DOI: 10.1161/circulationaha.105.568832] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND We have previously demonstrated that selective atrioventricular nodal (AVN) vagal stimulation (AVN-VS) can be used to control ventricular rate during atrial fibrillation (AF) in acute experiments. However, it is not known whether this approach could provide a long-term treatment in conscious animals. Thus, this study reports the first observations on the long-term efficacy and safety of this novel approach to control ventricular rate during AF in chronically instrumented dogs. METHODS AND RESULTS In 18 dogs, custom-made bipolar patch electrodes were sutured to the epicardial AVN fat pad for delivery of selective AVN-VS by a subcutaneously implanted nerve stimulator (pulse width 100 micros or 1 ms, frequency 20 or 160 Hz, amplitude 6 to 10 V). Fast-rate right atrial pacing (600 bpm) was used to induce and maintain AF. ECG, blood pressure, and body temperature were monitored telemetrically. One week after the induction of AF, AVN-VS was delivered and maintained for at least 5 weeks. It was found that AVN-VS had a consistent effect on ventricular rate slowing (on average 45+/-13 bpm) over the entire period of observation. Echocardiography showed improvement of cardiac indices with ventricular rate slowing. AVN-VS was well tolerated by the animals, causing no signs of distress or discomfort. CONCLUSIONS Beneficial long-term ventricular rate slowing during AF can be achieved by implantation of a nerve stimulator attached to the epicardial AVN fat pad. This novel concept is an attractive alternative to other methods of rate control and may be applicable in a selected group of patients.
Collapse
Affiliation(s)
- Youhua Zhang
- Department of Cardiovascular Medicine, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Rosenfeld LE. Atrial fibrillation: how to approach rate control. Curr Cardiol Rep 2005; 7:391-7. [PMID: 16105496 DOI: 10.1007/s11886-005-0094-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The optimal management of atrial fibrillation is of considerable clinical importance, and with the recent publication of four studies suggesting the equivalence of rate and rhythm control strategies, new attention has been focused on rate control. Reasons for rate control include reduction of symptoms and the prevention of tachycardia-mediated cardiomyopathy; yet, evidence-based definitions of optimal rate control are lacking. This article examines an approach to rate control that includes serial assessment of heart rate and symptoms, both at rest and with exertion, and the use of therapy tailored to the individual and modified over time (as no single therapy demonstrates clear superiority). Often, multidrug regimens including digoxin and a calcium channel blocker or beta-blocker are required, and in a minority of patients atrioventricular nodal ablation and pacing are necessary. Several novel therapies currently under development are also discussed.
Collapse
Affiliation(s)
- Lynda E Rosenfeld
- Section of Cardiovascular Medicine 3 FMP, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA.
| |
Collapse
|
21
|
|