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rotor ablation

Muhammad Balouch, Esra Gucuk Ipek, Jonathan Chrispin, Rizma J Bajwa, Tarek Zghaib, Ronald D Berger, Hiroshi Ashikaga, Saman Nazarian, Joseph E Marine, Hugh Calkins, David D Spragg
BACKGROUND: The utility of rotor ablation using commercially available systems as an adjunct to pulmonary vein isolation (PVI) is controversial. Variable results may stem from heterogeneous practice patterns. We investigated whether a prespecified protocol to determine temperospatial rotor stability improved acute and intermediate outcomes following rotor ablation. HYPOTHESIS: Protocolized rotor mapping and ablation, with prespecified metrics to determine temporal rotor stability prior to ablation, will improve short- and long-term PVI/rotor ablation outcomes...
January 25, 2017: Clinical Cardiology
Pawel Kuklik, Stef Zeemering, Arne van Hunnik, Bart Maesen, Laurent Pison, Dennis Lau, Jos Maessen, Piotr Podziemski, Christian Meyer, Benjamin Schaffer, Harry Crijns, Stephan Willems, Ulrich Schotten
OBJECTIVE: To explore technical challenges of phase singularity mapping during Atrial Fibrillation (AF) using direct contact electrograms. METHODS: AF mapping was performed in high-density epicardial recordings of human paroxysmal (PAF) or persistent (PersAF) (N=20 pts) AF with an array of 16x16 electrodes placed on atrial epicardium. Phase singularity (PS) points were detected using subsets of electrodes forming rings of varying size. RESULTS: PS detection using a 2x2 electrode ring identified 0...
April 15, 2016: IEEE Transactions on Bio-medical Engineering
Roland Richard Tilz, Tina Lin, Andreas Rillig, Christian-H Heeger, Leonie Scholz, Peter Wohlmuth, Tudor Bucur, Andreas Metzner, Shibu Mathew, Erik Wissner, Feifan Ouyang, Karl-Heinz Kuck
INTRODUCTION: Pulmonary vein isolation (PVI) is currently the gold standard for catheter ablation of atrial fibrillation (AF). The mechanism for AF-maintenance is still controversial. The concept of rapidly-activating spiral rotors perpetuating AF has led to the development of several rotor-mapping systems. We present our experience with focal impulse and rotor modulation (FIRM) using a 64-electrode basket catheter and computational system and evaluate its feasibility in conjunction with PVI to treat AF...
December 31, 2016: Journal of Cardiovascular Electrophysiology
Caroline H Roney, Jason D Bayer, Sohail Zahid, Marianna Meo, Patrick M J Boyle, Natalia A Trayanova, Michel Haïssaguerre, Rémi Dubois, Hubert Cochet, Edward J Vigmond
AIMS: Catheter ablation is an effective technique for terminating atrial arrhythmia. However, given a high atrial fibrillation (AF) recurrence rate, optimal ablation strategies have yet to be defined. Computer modelling can be a powerful aid but modelling of fibrosis, a major factor associated with AF, is an open question. Several groups have proposed methodologies based on imaging data, but no comparison to determine which methodology best corroborates clinically observed reentrant behaviour has been performed...
December 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Caroline H Roney, Chris D Cantwell, Norman A Qureshi, Rasheda A Chowdhury, Emmanuel Dupont, Phang Boon Lim, Edward J Vigmond, Jennifer H Tweedy, Fu Siong Ng, Nicholas S Peters
Extracellular electrograms recorded during atrial fibrillation (AF) are challenging to interpret due to the inherent beat-to-beat variability in amplitude and duration. Phase mapping represents these voltage signals in terms of relative position within the cycle, and has been widely applied to action potential and unipolar electrogram data of myocardial fibrillation. To date, however, it has not been applied to bipolar recordings, which are commonly acquired clinically. The purpose of this study is to present a novel algorithm for calculating phase from both unipolar and bipolar electrograms recorded during AF...
December 5, 2016: Annals of Biomedical Engineering
Lucas V A Boersma
No abstract text is available yet for this article.
November 24, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Ross Morgan, Michael A Colman, Henry Chubb, Gunnar Seemann, Oleg V Aslanidi
Introduction: The genesis of atrial fibrillation (AF) and success of AF ablation therapy have been strongly linked with atrial fibrosis. Increasing evidence suggests that patient-specific distributions of fibrosis may determine the locations of electrical drivers (rotors) sustaining AF, but the underlying mechanisms are incompletely understood. This study aims to elucidate a missing mechanistic link between patient-specific fibrosis distributions and AF drivers. Methods: 3D atrial models integrated human atrial geometry, rule-based fiber orientation, region-specific electrophysiology, and AF-induced ionic remodeling...
2016: Frontiers in Physiology
Jonathan S Steinberg, Yash Shah, Advay Bhatt, Tina Sichrovsky, Aysha Arshad, Emily Hansinger, Dan Musat
BACKGROUND: Focal impulse and rotor modulation (FIRM) was based on the premise that atrial fibrillation (AF) is sustained by rotors that are sufficiently stable to be eliminated by targeted ablation. Early experience reported high success as compared to conventional strategies. OBJECTIVE: The purpose of this study was to report on a single-center experience with extended follow-up by using FIRM in a variety of patients with AF. METHODS: All FIRM-guided ablation procedures were included...
November 5, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Stefan Georg Spitzer, László Károlyi, Carola Rämmler, Frank Scharfe, Thomas Weinmann, Mirko Zieschank, Anke Langbein
INTRODUCTION: A patient-tailored ablation approach focused on the elimination of both pulmonary vein triggers as well as substrate drivers may result in favorable outcomes in recurrent persistent AF patients. OBJECTIVE: We evaluated the long-term outcomes of rotor ablation combined with conventional pulmonary vein isolation (PVI) in patients with recurrent nonparoxysmal AF. METHODS: Fifty-eight consecutive patients underwent FIRM-guided rotor ablation followed by conventional PVI for the treatment of recurrent nonparoxysmal AF...
January 2017: Journal of Cardiovascular Electrophysiology
Amit Rozner, Sharon Zlochiver
Atrial ablation has been recently utilized to treat atrial fibrillation (AF) by isolation or destruction of arrhythmia drivers. In chronic or persistent AF patients these drivers often consist of one or few rotors at unknown locations, and several ablations are commonly conducted before arrhythmia is terminated. However, the irreversible damage done to the tissue may lead to AF recurrence. We propose an alternative strategy to terminate rotor activity by its attraction into a non 1:1 conducting region. The feasibility of the method was numerically tested in 2D models of chronic AF human atrial tissue...
September 7, 2016: Medical Engineering & Physics
Yoshio Takemoto, Rafael J Ramirez, Miki Yokokawa, Kuljeet Kaur, Daniela Ponce-Balbuena, Mohamad C Sinno, B Cicero Willis, Hamid Ghanbari, Steven R Ennis, Guadalupe Guerrero-Serna, Bettina C Henzi, Rakesh Latchamsetty, Roberto Ramos-Mondragon, Hassan Musa, Raphael P Martins, Sandeep V Pandit, Sami F Noujaim, Thomas Crawford, Krit Jongnarangsin, Frank Pelosi, Frank Bogun, Aman Chugh, Omer Berenfeld, Fred Morady, Hakan Oral, José Jalife
OBJECTIVES: To determine whether Gal-3 mediates sustained atrial fibrillation (AF)-induced atrial structural and electrical remodeling and contributes to AF perpetuation. BACKGROUND: Galectin-3 (Gal-3) mediates extracellular matrix remodeling in heart failure, but its role in AF progression remains unexplored. METHODS: We examined intracardiac blood samples from patients with AF (N=55) to identify potential biomarkers of AF recurrence. In a sheep model of tachypacing-induced AF (N=20), we tested the effects of Gal-3 inhibition during AF progression...
April 2016: JACC. Basic to Translational Science
Hiroshige Yamabe, Hisanori Kanazawa, Miwa Ito, Shozo Kaneko, Hisao Ogawa
BACKGROUND: It remains unclear whether atrial fibrillation (AF) is maintained by the rotor. OBJECTIVE: We evaluated the role of the rotor and examined its mechanism. METHODS: Among 75 patients with AF (60 paroxysmal, 15 persistent AF) who underwent 3-dimensional noncontact left atrial mapping during AF, we examined the prevalence and location of rotor activation and elucidated its mechanism. Catheter ablation was performed in a stepwise fashion (linear roof lesion and complex fractionated atrial electrogram ablation after pulmonary vein [PV) isolation) until AF termination...
December 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Changyong Li, Byounghyun Lim, Minki Hwang, Jun-Seop Song, Young-Seon Lee, Boyoung Joung, Hui-Nam Pak
BACKGROUND: We previously reported that stable rotors were observed in in-silico human atrial fibrillation (AF) models, and were well represented by dominant frequency (DF). We explored the spatiotemporal stability of DF sites in 3D-AF models imported from patient CT images of the left atrium (LA). METHODS: We integrated 3-D CT images of the LA obtained from ten patients with persistent AF (male 80%, 61.8 ± 13.5 years old) into an in-silico AF model. After induction, we obtained 6 seconds of AF simulation data for DF analyses in 30 second intervals (T1-T9)...
2016: PloS One
Lorenzo Gigli, Gian M Rosa, Maria I Tagliasacchi, Aldo Bonaventura, Luca Liberale, Fabrizio Montecucco, Federico Carbone, Giovanni Bertero, Claudio Brunelli
INTRODUCTION: Atrial fibrillation (AF) is a cardiac arrhythmia caused by various mechanisms, such as multiple re-entering wavelets, high frequency activity, and rotor sources. EVIDENCE ACQUISITION: This narrative review was based on papers found on PubMed and MEDLINE up to May 2016. The search terms were "atrial fibrillation" in combination with "catheter ablation, pathophysiology, antiarrhythmic drugs". EVIDENCE SYNTHESIS: Antiarrhythmic drugs are the cornerstone of therapy in AF, but their efficacy and safety might have to be improved...
April 2017: Minerva Cardioangiologica
Pieter W J Lozekoot, Monique M J de Jong, Orlando Parise, Francesco Matteucci, Fabiana Lucà, Narendra Kumar, Daniele Bani, Jens Czapla, Laurent Pison, Harry J G M Crijns, Jos G Maessen, Mark La Meir, Sandro Gelsomino
OBJECTIVE: We present the first testing study on the ABLA-BOX, a new in vitro module of hybrid atrial fibrillation ablation. METHODS: ABLA-BOX consists of two chambers that mimic the epicardial and endocardial sides of the heart. The septum between chambers provides catheter access on both sites of the cardiac tissue. A circuit, filled with freshly obtained porcine blood, including a pump, an oxygenator, and a heating device, circulate the blood inside the system...
May 2016: Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery
Karoly Kaszala, Kenneth A Ellenbogen
No abstract text is available yet for this article.
September 2016: Journal of Cardiovascular Electrophysiology
James N Weiss, Zhilin Qu, Kalyanam Shivkumar
Although considerable progress has been made in developing ablation approaches to cure atrial fibrillation (AF), outcomes are still suboptimal, especially for persistent and long-lasting persistent AF. In this topical review, we review the arrhythmia mechanisms, both reentrant and nonreentrant, that are potentially relevant to human AF at various stages/settings. We describe arrhythmia mapping techniques used to distinguish between the different mechanisms, with a particular focus on the detection of rotors...
September 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Sanghamitra Mohanty, Carola Gianni, Prasant Mohanty, Philipp Halbfass, Tamara Metz, Chintan Trivedi, Thomas Deneke, Gery Tomassoni, Rong Bai, Amin Al-Ahmad, Shane Bailey, John David Burkhardt, G Joseph Gallinghouse, Rodney Horton, Patrick M Hranitzky, Javier E Sanchez, Luigi Di Biase, Andrea Natale
BACKGROUND: Nonrandomized studies have reported focal impulse and rotor modulation (FIRM)-guided ablation to be superior to pulmonary vein antrum isolation (PVAI) for persistent atrial fibrillation and long-standing persistent atrial fibrillation. OBJECTIVES: This study sought to compare efficacy of FIRM ablation with or without PVAI versus PVAI plus non-PV trigger ablation in randomized persistent atrial fibrillation and long-standing persistent atrial fibrillation patients...
July 19, 2016: Journal of the American College of Cardiology
Jason D Bayer, Caroline H Roney, Ali Pashaei, Pierre Jaïs, Edward J Vigmond
Pulmonary vein isolation (PVI) with radiofrequency ablation (RFA) is the cornerstone of atrial fibrillation (AF) therapy, but few strategies exist for when it fails. To guide RFA, phase singularity (PS) mapping locates reentrant electrical waves (rotors) that perpetuate AF. The goal of this study was to test existing and develop new RFA strategies for terminating rotors identified with PS mapping. It is unsafe to test experimental RFA strategies in patients, so they were evaluated in silico using a bilayer computer model of the human atria with persistent AF (pAF) electrical (ionic) and structural (fibrosis) remodeling...
2016: Frontiers in Physiology
Dror M Bittner, Susanna L Stephens, Daniel P Zaleski, David P Tew, Nicholas R Walker, Anthony C Legon
Complexes of H3NCuF and H3NCuI have been synthesised in the gas phase and characterized by microwave spectroscopy. The rotational spectra of 4 isotopologues of H3NCuF and 5 isotopologues of H3NCuI have been measured in the 6.5-18.5 GHz frequency range using a chirped-pulse Fourier transform microwave spectrometer. Each complex is generated from a gas sample containing NH3 and a halogen-containing precursor diluted in Ar. Copper is introduced by laser ablation of a solid target prior to supersonic expansion of the sample into the vacuum chamber of the microwave spectrometer...
May 21, 2016: Physical Chemistry Chemical Physics: PCCP
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