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https://www.readbyqxmd.com/read/28733070/spatial-relationship-of-sites-for-atrial-fibrillation-drivers-and-atrial-tachycardia-in-patients-with-both-arrhythmias
#1
Tina Baykaner, Junaid A B Zaman, Albert J Rogers, Rachita Navara, Mahmood AlHusseini, Ryan T Borne, Shirley Park, Paul J Wang, David E Krummen, William H Sauer, Sanjiv M Narayan
INTRODUCTION: Atrial fibrillation (AF) often converts to and from atrial tachycardia (AT), but it is undefined if these rhythms are mechanistically related in such patients. We tested the hypothesis that critical sites for AT may be related to regional AF sources in patients with both rhythms, by mapping their locations and response to ablation on transitions to and from AF. METHODS: From 219 patients undergoing spatial mapping of AF prior to ablation at 3 centers, we enrolled 26 patients in whom AF converted to AT by ablation (n=19) or spontaneously (n=7; left atrial size 42±6cm, 38% persistent AF)...
July 14, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/28730829/mechanism-of-electrocardiographic-t-wave-flattening-in-diabetes-mellitus-experimental-and-simulation-study
#2
K A Sedova, J E Azarov, N V Arteyeva, A O Ovechkin, M A Vaykshnorayte, V A Vityazev, O G Bernikova, D N Shmakov, P Kneppo
In the present study we investigated the contribution of ventricular repolarization time (RT) dispersion (the maximal difference in RT) and RT gradients (the differences in RT in apicobasal, anteroposterior and interventricular directions) to T-wave flattening in a setting of experimental diabetes mellitus. In 9 healthy and 11 diabetic (alloxan model) open-chest rabbits, we measured RT in ventricular epicardial electrograms. To specify the contributions of apicobasal, interventricular and anteroposterior RT gradients and RT dispersion to the body surface potentials we determined T-wave voltage differences between modified upper- and lower-chest precordial leads (T-wave amplitude dispersions, TWAD)...
July 18, 2017: Physiological Research
https://www.readbyqxmd.com/read/28730712/slow-conduction-through-an-arc-of-block-a-basis-for-arrhythmia-formation-post-myocardial-infarction
#3
Eugene Patterson, Benjamin J Scherlag, Edward J Berbari, Ralph Lazzara
INTRODUCTION: The electrophysiologic basis for characteristic rate-dependent, constant-late-coupled (390+54 msec) premature ventricular beats (PVBs) present 4-5 days following coronary artery occlusion were examined in 108 anesthetized dogs. METHODS AND RESULTS: Fractionated/double potentials were observed in injured zone bipolar and composite electrograms at prolonged sinus cycle lengths (1296 ± 396 msec). At shorter cycle lengths, conduction of the delayed potential decremented, separating from the initial electrogram by a progressively prolonged isoelectric interval...
July 21, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28730651/a-comparison-of-the-electrophysiologic-and-electroanatomic-characteristics-between-the-right-and-left-atrium-in-persistent-atrial-fibrillation-is-the-right-atrium-a-window-into-the-left
#4
Sandeep Prabhu, Aleksandr Voskoboinik, Alex Ja McLellan, Kah Y Peck, Bupesh Pathik, Chrishan J Nalliah, Geoff R Wong, Sonia M Azzopardi, Geoffrey Lee, Justin Mariani, Liang-Han Ling, Andrew J Taylor, Jonathan M Kalman, Peter M Kistler
INTRODUCTION: The right atrium (RA) is readily accessible; however, it is unclear whether changes in the RA are representative of the LA. We performed detailed bi-atrial electroanatomic mapping to determine the electrophysiological relationship between the atria. METHODS AND RESULTS: Consecutive patients with persistent AF underwent bi-atrial electroanatomical mapping with a contact force catheter acquiring points with a CF > 10 g prior to ablation. Points were analyzed for tissue voltage, complex electrograms, low voltage (< 0...
July 21, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28727202/influence-of-the-left-atrial-contact-areas-on-fixed-low-voltage-zones-during-atrial-fibrillation-and-sinus-rhythm-in-persistent-atrial-fibrillation
#5
Shiro Nakahara, Yuichi Hori, Naoki Nishiyama, Yasuo Okumura, Reiko Fukuda, Sayuki Kobayashi, Takaaki Komatsu, Yoshihiko Sakai, Isao Taguchi
BACKGROUND: Atrial low-voltage zones (LVZ) are suggested as important factors for maintaining persistent atrial fibrillation (PsAF). The relationship between LVZs and left atrial (LA) contact areas (CoAs) is still unclear. OBJECTIVE: To assess whether CoA regions were involved in atrial substrate properties maintaining PsAF. METHODS: A total of 50 patients with PsAF (36 long-lasting) were analyzed. Three representative CoA detection areas (ascending aorta-anterior-LA, descending aorta-left pulmonary vein antrum, and vertebrae-posterior-LA) were registered on the mapping geometry...
July 20, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28717114/the-efficacy-of-isochronal-3d-mapping-based-ablation-of-ventricular-arrhythmia
#6
Masahito Suzuki, Junichi Nitta, Yosuke Hayashi, Kikou Lee, Keita Watanabe, Tatsuhiko Hirao, Nobutaka Kato, Yukihiro Inamura, Akira Sato, Masahiko Goya, Kenzo Hirao, Mitsuaki Isobe
Treatment of ventricular arrhythmias (VAs) commonly involves ablating sites showing electrograms with the earliest activity relative to the VA, but there is no threshold value for prematurity guaranteeing success. Ablation of sites with great prematurity can still result in failure.We hypothesized that isochronal map area (ISCA), derived from isochrones indicating electrogram prematurity, could help identify ablation targets in VA patients, as well as predict outcome. Specifically, we hypothesized that smaller ICSA for a given prematurity value would indicate a shallower arrhythmogenic focus leading to a higher likelihood of successful ablation...
July 14, 2017: International Heart Journal
https://www.readbyqxmd.com/read/28705875/electrical-and-structural-substrate-of-arrhythmogenic-right-ventricular-cardiomyopathy-determined-using-noninvasive-electrocardiographic-imaging-and-late-gadolinium-magnetic-resonance-imaging
#7
Christopher M Andrews, Neil T Srinivasan, Stefania Rosmini, Heerajnarain Bulluck, Michele Orini, Sharon Jenkins, Antonis Pantazis, William J McKenna, James C Moon, Pier D Lambiase, Yoram Rudy
BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a significant cause of sudden cardiac death in the young. Improved noninvasive assessment of ARVC and better understanding of the disease substrate are important for improving patient outcomes. METHODS AND RESULTS: We studied 20 genotyped ARVC patients with a broad spectrum of disease using electrocardiographic imaging (a method for noninvasive cardiac electrophysiology mapping) and advanced late gadolinium enhancement cardiac magnetic resonance scar imaging...
July 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28691870/recurrence-after-successful-catheter-ablation-for-ventricular-arrhythmia-from-the-aortic-root
#8
Zheng Liu, Xiaoqin Liu, Lan Ren, Xiandong Yin, Hao Han, Yuxin Wang, Wenning Deng, Yuhe Jia, Pihua Fang, Xinchun Yang
OBJECTIVE: The mechanism underlying recurrence after successful ablation of ventricular arrhythmias (VAs) was unclear. Spectrum analysis can help to identify near-field activation. The purpose of this study was to quantify the changes of near-field activation in response to ablation at the VAs origin in the aortic root (AR-VAs) and to assess its relationship with late ablation outcome. METHODS AND RESULTS: Patients who underwent acutely successful ablation for AR-VAs were analysed...
July 10, 2017: Acta Cardiologica
https://www.readbyqxmd.com/read/28687670/stand-alone-pulmonary-vein-isolation-versus-pulmonary-vein-isolation-with-additional-substrate-modification-as-index-ablation-procedures-in-patients-with-persistent-and-long-standing-persistent-atrial-fibrillation-the-randomized-alster-lost-af-trial-ablation
#9
Thomas Fink, Michael Schlüter, Christian-Hendrik Heeger, Christine Lemes, Tilman Maurer, Bruno Reissmann, Johannes Riedl, Laura Rottner, Francesco Santoro, Boris Schmidt, Peter Wohlmuth, Shibu Mathew, Christian Sohns, Feifan Ouyang, Andreas Metzner, Karl-Heinz Kuck
BACKGROUND: Pulmonary vein isolation (PVI) for persistent atrial fibrillation is associated with limited success rates and often requires multiple procedures to maintain stable sinus rhythm. In the prospective and randomized Alster-Lost-AF trial (Ablation at St. Georg Hospital for Long-Standing Persistent Atrial Fibrillation), we sought to assess, in patients with symptomatic persistent or long-standing persistent atrial fibrillation, the outcomes of initial ablative strategies comprising either stand-alone PVI (PVI-only approach) or a stepwise approach of PVI followed by complex fractionated atrial electrogram ablation and linear ablation (Substrate-modification approach)...
July 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28682320/management-of-atrial-high-rate-episodes-detected-by-cardiac-implanted-electronic-devices
#10
REVIEW
Ben Freedman, Giuseppe Boriani, Taya V Glotzer, Jeff S Healey, Paulus Kirchhof, Tatjana S Potpara
Cardiac implanted electronic devices (CIEDs), including pacemakers and implantable defibrillators that perform atrial sensing typically using an atrial electrode, frequently detect subclinical atrial high-rate episodes (AHREs). When the intracardiac electrograms are carefully examined, the majority of AHREs are atrial fibrillation (AF) or other atrial tachyarrhythmias, which have been shown to be associated with both an increased risk of stroke, and subsequent development of clinical AF. However, the absolute risk of stroke among patients with AHREs is less than might be expected for clinically diagnosed paroxysmal AF...
July 6, 2017: Nature Reviews. Cardiology
https://www.readbyqxmd.com/read/28678875/evaluation-of-the-use-of-unipolar-voltage-amplitudes-for-detection-of-myocardial-scar-assessed-by-cardiac-magnetic-resonance-imaging-in-heart-failure-patients
#11
Uyên Châu Nguyên, Francesco Maffessanti, Masih Mafi-Rad, Giulio Conte, Stef Zeemering, François Regoli, Maria Luce Caputo, Antonius M W van Stipdonk, Sebastiaan C A M Bekkers, Daniel Suerder, Tiziano Moccetti, Rolf Krause, Frits W Prinzen, Kevin Vernooy, Angelo Auricchio
BACKGROUND: Validation of voltage-based scar delineation has been limited to small populations using mainly endocardial measurements. The aim of this study is to compare unipolar voltage amplitudes (UnipV) with scar on delayed enhancement cardiac magnetic resonance imaging (DE-CMR). METHODS: Heart failure patients who underwent DE-CMR and electro-anatomic mapping were included. Thirty-three endocardial mapped patients and 27 epicardial mapped patients were investigated...
2017: PloS One
https://www.readbyqxmd.com/read/28678805/ablation-as-targeted-perturbation-to-rewire-communication-network-of-persistent-atrial-fibrillation
#12
Susumu Tao, Samuel F Way, Joshua Garland, Jonathan Chrispin, Luisa A Ciuffo, Muhammad A Balouch, Saman Nazarian, David D Spragg, Joseph E Marine, Ronald D Berger, Hugh Calkins, Hiroshi Ashikaga
Persistent atrial fibrillation (AF) can be viewed as disintegrated patterns of information transmission by action potential across the communication network consisting of nodes linked by functional connectivity. To test the hypothesis that ablation of persistent AF is associated with improvement in both local and global connectivity within the communication networks, we analyzed multi-electrode basket catheter electrograms of 22 consecutive patients (63.5 ± 9.7 years, 78% male) during persistent AF before and after the focal impulse and rotor modulation-guided ablation...
2017: PloS One
https://www.readbyqxmd.com/read/28674778/the-temporal-behavior-and-consistency-of-bipolar-atrial-electrograms-in-human-persistent-atrial-fibrillation
#13
Tiago P Almeida, Gavin S Chu, Michael J Bell, Xin Li, João L Salinet, Nawshin Dastagir, Jiun H Tuan, Peter J Stafford, G André Ng, Fernando S Schlindwein
The unstable temporal behavior of atrial electrical activity during persistent atrial fibrillation (persAF) might influence ablation target identification, which could explain the conflicting persAF ablation outcomes in previous studies. We sought to investigate the temporal behavior and consistency of atrial electrogram (AEG) fractionation using different segment lengths. Seven hundred ninety-seven bipolar AEGs were collected with three segment lengths (2.5, 5,and 8 s) from 18 patients undergoing persAF ablation...
July 3, 2017: Medical & Biological Engineering & Computing
https://www.readbyqxmd.com/read/28670858/rotors-exhibit-greater-surface-ecg-variation-during-ventricular-fibrillation-than-focal-sources-due-to-wavebreak-secondary-rotors-and-meander
#14
Gordon Ho, Christopher T Villongco, Omid Yousefian, Aaron Bradshaw, Andrew Nguyen, Yonatan Faiwiszewski, Justin Hayase, Wouter-Jan Rappel, Andrew D McCulloch, David E Krummen
INTRODUCTION: Ventricular fibrillation is a common life-threatening arrhythmia. The ECG of VF appears chaotic but may allow identification of sustaining mechanisms to guide therapy. HYPOTHESIS: We hypothesized that rotors and focal sources manifest distinct features on the ECG, and computational modeling may identify mechanisms of such features. METHODS: VF induction was attempted in 31 patients referred for ventricular arrhythmia ablation...
July 3, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28657676/rate-disparity-of-near-field-vs-far-field-icd-electrograms-a-clue-to-the-diagnosis-of-dissimilar-ventricular-rhythms
#15
EDITORIAL
Andreas Kucher, S S Barold
No abstract text is available yet for this article.
June 28, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28644155/transvenous-before-surgical-hybrid-procedure
#16
Joseph J Tiano, Robert Drennan, John Novella, Rafael Squiteri, Malcolm Robinson, Albert DiMeo, Lindsey Scierka, Paul LeLorier
BACKGROUND: Historically, persistent atrial fibrillation (PeAF) and long standing persistent atrial fibrillation (LSPeAF) have demonstrated limited clinical success despite hybrid approaches. OBJECTIVE: We describe our experience with the endocardial-before-epicardial approach defined by a comprehensive endovascular approach preceding and guiding the epicardial approach which includes an extensive posterior wall ablation. METHODS: 40 patients were followed over a 12 month period...
May 2017: Journal of the Louisiana State Medical Society: Official Organ of the Louisiana State Medical Society
https://www.readbyqxmd.com/read/28643171/elimination-of-the-negative-component-of-the-unipolar-electrogram-as-a-local-procedural-endpoint-during-paroxysmal-atrial-fibrillation-catheter-ablation-using-contact-force-sensing-the-uniforce-study
#17
Agustín Bortone, Philippe Lagrange, Bruno Cauchemez, Cyril Durand, Pierre Dieuzaide, Sébastien Prévot, Alexis Mechulan, Thomas Pambrun, Ruairidh Martin, Pauline Parlier, Alexandre Masse, Eloi Marijon, Jean-Paul Albenque
PURPOSE: Elimination of the negative component of the unipolar atrial electrogram is a reliable indicator of the creation of a transmural lesion. Contact-force (CF) sensing technology has the potential to increase the durability of pulmonary vein isolation (PVI). In the present multicenter study, we assessed the 2-year sinus rhythm (SR) maintenance rate in patients with paroxysmal atrial fibrillation (PAF) after PVI guided by these two approaches. METHODS: Two hundred fifteen consecutive PAF patients (62...
June 22, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28641242/arrhythmia-mechanism-and-scaling-effect-on-the-spectral-properties-of-electroanatomical-maps-with-manifold-harmonics
#18
Margarita Sanroman-Junquera, Inmaculada Mora-Jimenez, Arcadi Garcia-Alberola, Antonio J Caamano, Beatriz Trenor, Jose Luis Rojo-Alvarez
Spatial and temporal processing of intracardiac electrograms provides relevant information to support the arrhythmia ablation during electrophysiological studies. Current Cardiac Navigation Systems (CNS) and Electrocardiographic Imaging (ECGI) build detailed three-dimensional electroanatomical maps (EAM), which represent the spatial anatomical distribution of bioelectrical features, such as activation time or voltage. We present a principled methodology for spectral analysis of both EAM geometry and bioelectrical feature in CNS or ECGI, including their spectral representation, cut-off frequency, or spatial sampling rate (SSR)...
June 15, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28639747/the-effect-of-activation-rate-on-left-atrial-bipolar-voltage-in-patients-with-paroxysmal-atrial-fibrillation
#19
Steven E Williams, Nick Linton, Louisa O'Neill, James Harrison, John Whitaker, Rahul Mukherjee, Christopher A Rinaldi, Jaswinder Gill, Steven Niederer, Matthew Wright, Mark O'Neill
INTRODUCTION: Bipolar voltage is used during electroanatomic mapping to define abnormal myocardium, but the effect of activation rate on bipolar voltage is not known. We hypothesized that bipolar voltage may change in response to activation rate. By examining corresponding unipole signals we sought to determine the mechanisms of such changes. METHODS AND RESULTS: LA extrastimulus mapping was performed during CS pacing in 10 patients undergoing 1(st) time paroxysmal atrial fibrillation ablation...
June 22, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28630171/distinctive-left-ventricular-activations-associated-with-ecg-pattern-in-heart-failure-patients
#20
Nicolas Derval, Josselin Duchateau, Saagar Mahida, Romain Eschalier, Frederic Sacher, Joost Lumens, Hubert Cochet, Arnaud Denis, Xavier Pillois, Seigo Yamashita, Yuki Komatsu, Sylvain Ploux, Sana Amraoui, Adlane Zemmoura, Philippe Ritter, Mélèze Hocini, Michel Haissaguerre, Pierre Jaïs, Pierre Bordachar
BACKGROUND: In contrast to patients with left bundle branch block (LBBB), heart failure patients with narrow QRS and nonspecific intraventricular conduction delay (NICD) display a relatively limited response to cardiac resynchronization therapy. We sought to compare left ventricular (LV) activation patterns in heart failure patients with narrow QRS and NICD to patients with LBBB using high-density electroanatomic activation maps. METHODS AND RESULTS: Fifty-two heart failure patients (narrow QRS [n=18], LBBB [n=11], NICD [n=23]) underwent 3-dimensional electroanatomic mapping with a high density of mapping points (387±349 LV)...
June 2017: Circulation. Arrhythmia and Electrophysiology
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