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frequency domain atrial fibrillation ablation

Mu Qin, Xu Liu, Wei-Feng Jiang, Shao-Hui Wu, Xiao-Dong Zhang, Sunny Po
BACKGROUND: The role of autonomic innervation around the pulmonary vein (PV) antrum in the genesis of atrial fibrillation (AF) has been demonstrated but the characteristics of radiofrequency induced vagal response (VR) in the PV antrum and its clinical impact on pulmonary vein isolation (PVI) for paroxysmal AF need to be further elucidated. METHOD: Of 995 consecutive patients with symptomatic paroxysmal AF undergoing PVI at a single center over a 2-year period, 516 met exclusion criteria and the remaining 479 patients, 156 positive VR (PVR) and 323 negative VR (NVR), underwent 12-month follow-up...
May 15, 2016: International Journal of Cardiology
María S Guillem, Andreu M Climent, Miguel Rodrigo, Francisco Fernández-Avilés, Felipe Atienza, Omer Berenfeld
Rotor-guided ablation has opened new perspectives into the therapy of atrial fibrillation (AF). Analysis of the spatio-temporal cardiac excitation patterns in the frequency and phase domains has demonstrated the importance of rotors in research models of AF, however, the dynamics and role of rotors in human AF are still controversial. In this review, the current knowledge gained through research models and patient data that support the notion that rotors are key players in AF maintenance is summarized. We report and discuss discrepancies regarding rotor prevalence and stability in various studies, which can be attributed in part to methodological differences among mapping systems...
April 1, 2016: Cardiovascular Research
Shiro Nakahara, Takanori Yamaguchi, Yuichi Hori, Naofumi Anjo, Akiko Hayashi, Sayuki Kobayashi, Takaaki Komatsu, Yoshihiko Sakai, Akira Fukui, Takeshi Tsuchiya, Isao Taguchi
INTRODUCTION: Atrial low-voltage zones (LVZs) may be related to maintenance of atrial fibrillation (AF). The influence of left atrial (LA) contact areas (CoAs) on reentrant or rotor-like sources maintaining AF has not been investigated. METHODS AND RESULTS: Forty patients with persistent AF (PsAF) were analyzed. Three representative CoA regions in the LA (ascending aorta: anterior wall; descending aorta: left inferior pulmonary vein; and vertebrae: posterior wall) were visualized by enhanced CT...
May 2016: Journal of Cardiovascular Electrophysiology
A Orozco-Duque, J D Martinez-Vargas, D Novak, J Bustamante, G Castellanos-Dominguez
Radiofrequency catheter ablation of atrial fibrillation (AF) guided by complex fractionated atrial electrograms (CFAE) is associated with a high AF termination rate in paroxysmal AF, but not in persistent. CFAE does not always identify favorable sites for persistent AF ablation. Studies suggest that only high fractionation level should be used as a target site for ablation. Nonetheless, there are not a standardized criterion to defined fractionation levels. Therefore, a better characterization of the signal is required providing a set of more powerful features that should be extracted from CFAE...
2014: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Flavia Ravelli, Michela Masè, Alessandro Cristoforetti, Massimiliano Marini, Marcello Disertori
The identification of suitable markers for critical patterns during atrial fibrillation (AF) may be crucial to guide an effective ablation treatment. Single parameter maps, based on dominant frequency and complex fractionated electrograms, have been proposed as a tool for electrogram-guided ablation, however the specificity of these markers is debated. Experimental studies suggest that AF critical patterns may be identified on the basis of specific rate and organization features, where rapid organized and rapid fragmented activities characterize respectively localized sources and critical substrates...
August 2014: Progress in Biophysics and Molecular Biology
Yenn-Jiang Lin, Men-Tzung Lo, Chen Lin, Shih-Lin Chang, Li-Wei Lo, Yu-Feng Hu, Tze-Fan Chao, Cheng-Hung Li, Yi-Chung Chang, Wan-Hsin Hsieh, Fa-Po Chung, Hsuan-Ming Tsao, Hung-Yu Chang, Norden E Huang, Shih-Ann Chen
INTRODUCTION: Currently, the identification of complex fractionated atrial electrograms (CFEs) in the substrate modification is mostly based on cycle length-derived algorithms. The characteristics of the fibrillation electrogram morphology and their consistency over time are not clear. The aim of this study was to optimize the detection algorithm of crucial CFEs by using nonlinear measure electrogram similarity. METHODS AND RESULTS: One hundred persistent atrial fibrillation patients that underwent catheter ablation were included...
March 2013: Journal of Cardiovascular Electrophysiology
Yenn-Jiang Lin, Shih-Lin Chang, Li-Wei Lo, Yu-Feng Hu, Kazuyoshi Suenari, Cheng-Hung Li, Tze-Fan Chao, Fa-Po Chung, Jo-Nan Liao, Beny Hartono, Han-Wen Tso, Hsuan-Ming Tsao, Jin-Long Huang, Tsair Kao, Shih-Ann Chen
INTRODUCTION: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high-frequency AF nests may have a higher efficacy. METHODS AND RESULTS: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled...
November 2012: Journal of Cardiovascular Electrophysiology
Laszlo Saghy, David J Callans, Fermin Garcia, David Lin, Francis E Marchlinski, Michael Riley, Sanjay Dixit, Wendy S Tzou, Harris M Haqqani, Robert Pap, Steven Kim, Edward P Gerstenfeld
BACKGROUND: Ablation of persistent atrial fibrillation (AF) may require adjunctive methods of substrate modification. Both ablation-targeting complex fractionated atrial electrograms (CFAEs) recorded during AF and fractionated electrograms recorded during sinus rhythm (sinus rhythm fractionation [SRF]) have been described. However, the relationship of CFAEs with SRF is unclear. METHODS: Twenty patients (age 62 ± 9 years, 13 males) with persistent AF and 9 control subjects without organic heart disease or AF (age 36 ± 6 years, 4 males) underwent detailed CFAE and SRF left atrial electroanatomic maps...
February 2012: Heart Rhythm: the Official Journal of the Heart Rhythm Society
David Filgueiras-Rama, Raphael Pedro Martins, Steven R Ennis, Sergey Mironov, Jiang Jiang, Masatoshi Yamazaki, Jérôme Kalifa, Josè Jalife, Omer Berenfeld
Atrial fibrillation (AF) is a complex cardiac arrhythmia with high morbidity and mortality.(1,2) It is the most common sustained cardiac rhythm disturbance seen in clinical practice and its prevalence is expected to increase in the coming years.(3) Increased intra-atrial pressure and dilatation have been long recognized to lead to AF,(1,4) which highlights the relevance of using animal models and stretch to study AF dynamics. Understanding the mechanisms underlying AF requires visualization of the cardiac electrical waves with high spatial and temporal resolution...
2011: Journal of Visualized Experiments: JoVE
Jiun Tuan, Mohamed Jeilan, Suman Kundu, Will Nicolson, Irene Chung, Peter J Stafford, G André Ng
AIMS: The aim was to study regional fractionation and dominant frequency (DF) to determine if any relationship exists between the two parameters and also to assess the impact of limited left atrial ablation. METHODS AND RESULTS: Patients undergoing catheter ablation of persistent AF using three-dimensional navigation were studied. Regional left atrial electrograms were analysed in the frequency domain by assessing DF and organization index (OI), and for degree of fractionation [using complex fractionated electrograms (CFE)-mean] before and after circumferential pulmonary vein and left atrial roof ablation...
November 2011: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Omer Berenfeld, Steve Ennis, Elliot Hwang, Brian Hooven, Krzysztof Grzeda, Sergey Mironov, Masatoshi Yamazaki, Jérôme Kalifa, José Jalife
BACKGROUND: Time- and frequency-domain estimates of activation rate have been proposed to guide atrial fibrillation (AF) ablation in patients, but their electrophysiological correlates are unclear. OBJECTIVE: This study sought to examine the relative correlation of average electrical cycle length (CL) and dominant frequency (DF) during AF with reference optical mapping measures. METHODS: Eight sheep hearts were Langendorff-perfused and superfused with oxygenated Tyrode solution inside a tank representing the human thorax...
November 2011: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Demosthenes G Katritsis, Ioannis Pantos, Efstathios P Efstathopoulos
Catheter ablation is an established therapeutic option for certain patients with atrial fibrillation (AF), but the reported success rates of anatomically oriented ablation techniques are low compared with those for other ablation indications, particularly for persistent AF. Electrophysiologically oriented ablation techniques have emerged over the last decade that aim at modifying the arrhythmogenic substrate to the extent that it cannot maintain fibrillatory activity. Electrogram-guided ablation procedures are the most common substrate-targeted ablation approaches and can be broadly divided into procedures that target atrial sites with particular electrogram characteristics in either the time domain (complex fractionated electrograms) or frequency components in the frequency domain (dominant frequencies)...
May 2011: Expert Review of Cardiovascular Therapy
Sheng-Hsiung Chang, Magnus Ulfarsson, Aman Chugh, Kentaro Yoshida, Krit Jongnarangsin, Thomas Crawford, Eric Good, Frank Pelosi, Frank Bogun, Fred Morady, Hakan Oral
BACKGROUND: Complex fractionated atrial electrograms (CFAE) have been considered to be helpful during catheter ablation of atrial fibrillation (AF). The purpose of this study was to analyze the characteristics of CFAEs recorded during sinus rhythm (SR) and AF, and to determine their relationship to perpetuation of AF and clinical outcome. METHODS AND RESULTS: Antral pulmonary vein isolation (APVI) was performed in 34 consecutive patients (age = 59 ± 10 years) with paroxysmal AF who presented in SR...
August 2011: Journal of Cardiovascular Electrophysiology
Angelo B Biviano, James Coromilas, Edward J Ciaccio, William Whang, Kathleen Hickey, Hasan Garan
BACKGROUND: Atrial fibrillation (AF) activation rates have been calculated using both frequency domain and time complex analyses. Direct comparisons of these methods are limited. We report: (1) their correlation when measuring AF activation rates, (2) comparisons of recording durations required to minimize variability, and (3) differences in the temporal reproducibility. METHODS: AF activation rates were calculated using domain frequency (DF) (via fast Fourier transform) and time complex (TC) (via beat-to-beat activation measurements) analyses...
May 2011: Pacing and Clinical Electrophysiology: PACE
Ulrike Richter, Luca Faes, Alessandro Cristoforetti, Michela Masè, Flavia Ravelli, Martin Stridh, Leif Sörnmo
The purpose of this study is to investigate propagation patterns in intracardiac signals recorded during atrial fibrillation (AF) using an approach based on partial directed coherence (PDC), which evaluates directional coupling between multiple signals in the frequency domain. The PDC is evaluated at the dominant frequency of AF signals and tested for significance using a surrogate data procedure specifically designed to assess causality. For significantly coupled sites, the approach allows also to estimate the delay in propagation...
January 2011: Annals of Biomedical Engineering
Omer Berenfeld
Atrial fibrillation (AF) is the main cause of stroke and the most common sustained arrhythmia, afflicting about 2.3 million Americans. Clinical treatment and management of AF would benefit from a noninvasive and global assessment of the arrhythmia; however, that avenue seems currently limited in part by our poor understanding of arrhythmia itself. Experimental studies of AF in the isolated sheep heart demonstrated that high-frequency sources in the posterior wall of the left atrium drive the fibrillatory activity throughout both atria...
November 2010: Journal of Electrocardiology
Jiun Tuan, Faizel Osman, Mohamed Jeilan, Suman Kundu, Rajkumar Mantravadi, Peter J Stafford, G André Ng
AIMS: The mechanism of the action of flecainide in the termination of human atrial fibrillation (AF) is not fully understood. We studied the acute effects of flecainide on AF electrograms in the time and frequency domain to identify factors associated with AF termination. METHODS AND RESULTS: Patients who were still in AF at the end of catheter ablation for AF were given intravenous flecainide. Dominant frequency (DF) and organization index (OI) were obtained by fast Fourier transform of electrograms from the coronary sinus catheter over 10 s in AF, before and after flecainide infusion...
April 2010: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Stanley Nattel
No abstract text is available yet for this article.
October 2009: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Krzysztof R Grzeda, Sami F Noujaim, Omer Berenfeld, José Jalife
BACKGROUND: Complex fractionated atrial electrograms (CFAEs) are thought to identify high-frequency electrical sources and have become an important target for radiofrequency ablation of atrial fibrillation (AF). Methods used to identify CFAEs and locate suitable ablation sites usually depend on subjective analysis of the electrograms but may also involve objective, computer-based paradigms through either time- or frequency-domain approaches. METHODS: We generated a set of simulated test electrograms, which were defined by a combination of a basic cycle length, phase-resetting noise, and phase-preserving noise, accounting for far-field effects...
October 2009: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Rolf Franck Berntsen, Alan Cheng, Hugh Calkins, Ronald D Berger
AIMS: Areas with complex fractionated electrograms are commonly targeted during ablation of persistent atrial fibrillation (AF). These signals are, however, found in most sampled areas of the left atrium (LA), implying the need for further differentiation. METHODS AND RESULTS: Electrograms were recorded over 60 s at eight different LA endocardial sites in 10 patients with persistent AF, using a fully automated algorithm. These were analysed in sequential 2 s segments for activity, mean amplitude, continuous activity percentage, and dominant frequency (DF)...
March 2009: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
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