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Unipolar mapping

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https://www.readbyqxmd.com/read/28887361/technical-considerations-on-phase-mapping-for-identification-of-atrial-reentrant-activity-in-direct-and-inverse-computed-electrograms
#1
Miguel Rodrigo, Andreu M Climent, Alejandro Liberos, Francisco Fernández-Avilés, Omer Berenfeld, Felipe Atienza, Maria S Guillem
BACKGROUND: Phase mapping has become a broadly used technique to identify atrial reentrant circuits for ablative therapy guidance. This work studies the phase mapping process and how the signal nature and its filtering affect the reentrant pattern characterization in electrogram (EGM), body surface potential mapping, and electrocardiographic imaging signals. METHODS AND RESULTS: EGM, body surface potential mapping, and electrocardiographic imaging phase maps were obtained from 17 simulations of atrial fibrillation, atrial flutter, and focal atrial tachycardia...
September 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28862787/panoramic-atrial-mapping-with-basket-catheters-a-quantitative-analysis-to-optimize-practice-patient-selection-and-catheter-choice
#2
Shohreh Honarbakhsh, Richard J Schilling, Rui Providência, Gurpreet Dhillon, Vinit Sawhney, Claire A Martin, Emily Keating, Malcolm Finlay, Syed Ahsan, Anthony Chow, Mark J Earley, Ross J Hunter
INTRODUCTION: Panoramic mapping with basket catheters have been used to map atrial fibrillation (AF). However, the limited tissue contact and coverage achieved has raised concerns. METHODS AND RESULTS: Patients undergoing catheter ablation for atrial tachycardia (AT) and persistent AF were recruited. Unipolar signals were recorded with the Constellation or FIRMap catheters. The proportion and distribution of anatomical coverage by the catheters was determined and tissue contact achieved measured...
September 1, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28798020/unipolar-endocardial-voltage-mapping-in-the-right-ventricle-optimal-cutoff-values-correcting-for-computed-tomography-derived-epicardial-fat-thickness-and-their-clinical-value-for-substrate-delineation
#3
Jeroen Venlet, Sebastiaan R D Piers, Gijsbert F L Kapel, Marta de Riva, Philippe F G Pauli, Rob J van der Geest, Katja Zeppenfeld
BACKGROUND: Low endocardial unipolar voltage (UV) at sites with normal bipolar voltage (BV) may indicate epicardial scar. Currently applied UV cutoff values are based on studies that lacked epicardial fat information. This study aimed to define endocardial UV cutoff values using computed tomography-derived fat information and to analyze their clinical value for right ventricular substrate delineation. METHODS AND RESULTS: Thirty-three patients (50±14 years; 79% men) underwent combined endocardial-epicardial right ventricular electroanatomical mapping and ablation of right ventricular scar-related ventricular tachycardia with computed tomographic image integration, including computed tomography-derived fat thickness...
August 2017: Circulation. Arrhythmia and 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 J A McLellan, Kah Y Peck, Bhupesh 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 biatrial electroanatomic mapping to determine the electrophysiological relationship between the atria. METHODS AND RESULTS: Consecutive patients with persistent AF underwent biatrial 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/28678875/evaluation-of-the-use-of-unipolar-voltage-amplitudes-for-detection-of-myocardial-scar-assessed-by-cardiac-magnetic-resonance-imaging-in-heart-failure-patients
#6
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/28639747/the-effect-of-activation-rate-on-left-atrial-bipolar-voltage-in-patients-with-paroxysmal-atrial-fibrillation
#7
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/28553365/mini-electrodes-on-ablation-catheters-valuable-addition-or-redundant-information-insights-from-a-computational-study
#8
Stefan Pollnow, Joachim Greiner, Tobias Oesterlein, Eike M Wülfers, Axel Loewe, Olaf Dössel
Radiofrequency ablation has become a first-line approach for curative therapy of many cardiac arrhythmias. Various existing catheter designs provide high spatial resolution to identify the best spot for performing ablation and to assess lesion formation. However, creation of transmural and nonconducting ablation lesions requires usage of catheters with larger electrodes and improved thermal conductivity, leading to reduced spatial sensitivity. As trade-off, an ablation catheter with integrated mini electrodes was introduced...
2017: Computational and Mathematical Methods in Medicine
https://www.readbyqxmd.com/read/28546283/high-resolution-mapping-of-gastric-slow-wave-recovery-profiles-biophysical-model-methodology-and-demonstration-of-applications
#9
N Paskaranandavadivel, L K Cheng, P Du, J M Rogers, G O'Grady
Slow waves play a central role in coordinating gastric motor activity. High-resolution mapping of extracellular potentials from the stomach provides spatiotemporal detail on normal and dysrhythmic slow-wave patterns. All mapping studies to date have focused exclusively on tissue activation; however, the recovery phase contains vital information on repolarization heterogeneity, the excitable gap, and refractory tail interactions but has not been investigated. Here, we report a method to identify the recovery phase in slow-wave mapping data...
September 1, 2017: American Journal of Physiology. Gastrointestinal and Liver Physiology
https://www.readbyqxmd.com/read/28536891/myocardial-voltage-ratio-in-arrhythmogenic-right-ventricular-dysplasia-cardiomyopathy
#10
REVIEW
Andreas Müssigbrodt, Livio Bertagnolli, Elena Efimova, Jedrzej Kosiuk, Borislav Dinov, Kerstin Bode, Simon Kircher, Nikolaos Dagres, Michael Döring, Sergio Richter, Philipp Sommer, Daniela Husser, Andreas Bollmann, Gerhard Hindricks, Arash Arya
AIMS: This study aimed to analyze the influence of scar distribution between the endocardium and the epicardium in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). METHODS: Electroanatomical mapping data were derived from our ARVD/C registry. Myocardial voltage distribution between the endocardium and the epicardium was analyzed in 28 patients (18 men, 49.9 ± 13.0 years) with previous ventricular tachycardia (VT) ablation and complete right ventricular maps...
June 2017: Herzschrittmachertherapie & Elektrophysiologie
https://www.readbyqxmd.com/read/28525920/torsade-de-pointes-arrhythmias-arise-at-the-site-of-maximal-heterogeneity-of-repolarization-in-the-chronic-complete-atrioventricular-block-dog
#11
Albert Dunnink, Thom R G Stams, Alexandre Bossu, Veronique M F Meijborg, Jet D M Beekman, Sofieke C Wijers, Jacques M T De Bakker, Marc A Vos
Aims: The chronic complete atrioventricular block (CAVB) dog is highly sensitive for drug-induced torsade de pointes (TdP) arrhythmias. Focal mechanisms have been suggested as trigger for TdP onset; however, its exact mechanism remains unclear. In this study, detailed mapping of the ventricles was performed to assess intraventricular heterogeneity of repolarization in relation to the initiation of TdP. Methods and results: In 8 CAVB animals, 56 needles, each containing 4 electrodes, were inserted in the ventricles...
May 1, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28504840/clinical-utility-of-a-short-resting-state-mri-scan-in-differentiating-bipolar-from-unipolar-depression
#12
M Li, T Das, W Deng, Q Wang, Y Li, L Zhao, X Ma, Y Wang, H Yu, X Li, Y Meng, L Palaniyappan, T Li
OBJECTIVE: Depression in bipolar disorder (BipD) requires a therapeutic approach that is from treating unipolar major depressive disorder (UniD), but to date, no reliable methods could separate these two disorders. The aim of this study was to establish the clinical validity and utility of a non-invasive functional MRI-based method to classify BipD from UniD. METHOD: The degree of connectivity (degree centrality or DC) of every small unit (voxel) with every other unit of the brain was estimated in 22 patients with BipD and 22 age, gender, and depressive severity-matched patients with UniD and 22 healthy controls...
September 2017: Acta Psychiatrica Scandinavica
https://www.readbyqxmd.com/read/28500175/spatial-resolution-requirements-for-accurate-identification-of-drivers-of-atrial-fibrillation
#13
COMPARATIVE STUDY
Caroline H Roney, Chris D Cantwell, Jason D Bayer, Norman A Qureshi, Phang Boon Lim, Jennifer H Tweedy, Prapa Kanagaratnam, Nicholas S Peters, Edward J Vigmond, Fu Siong Ng
BACKGROUND: Recent studies have demonstrated conflicting mechanisms underlying atrial fibrillation (AF), with the spatial resolution of data often cited as a potential reason for the disagreement. The purpose of this study was to investigate whether the variation in spatial resolution of mapping may lead to misinterpretation of the underlying mechanism in persistent AF. METHODS AND RESULTS: Simulations of rotors and focal sources were performed to estimate the minimum number of recording points required to correctly identify the underlying AF mechanism...
May 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28479513/epicardial-endocardial-breakthrough-during-stable-atrial-macroreentry-evidence-from-ultra-high-resolution-3-dimensional-mapping
#14
Bhupesh Pathik, Geoffrey Lee, Frédéric Sacher, Michel Haïssaguerre, Pierre Jaïs, Grégoire Massoullié, Nicolas Derval, Prashanthan Sanders, Peter Kistler, Jonathan M Kalman
BACKGROUND: Evidence for epicardial-endocardial breakthrough (EEB) is derived from mapping inferences in patients with atrial fibrillation who may also have focal activations. OBJECTIVE: The purpose of this study was to investigate whether EEB could be discerned during stable right atrial (RA) macroreentry using high-density high-spatial resolution 3-dimensional mapping. METHODS: Macroreentry was diagnosed using 3-dimensional mapping and entrainment...
May 4, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28472282/right-ventricular-outflow-tract-high-density-endocardial-unipolar-voltage-mapping-in-patients-with-brugada-syndrome-evidence-for-electroanatomical-abnormalities
#15
Konstantinos P Letsas, Michael Efremidis, Konstantinos Vlachos, Stamatis Georgopoulos, Nikolaos Karamichalakis, Dimitrios Asvestas, Kosmas Valkanas, Panagiotis Korantzopoulos, Tong Liu, Antonios Sideris
Aims: Epicardial structural abnormalities at the right ventricular outflow tract (RVOT) may provide the arrhythmia substrate in Brugada syndrome (BrS). Electroanatomical endocardial unipolar voltage mapping is an emerging tool that accurately identifies epicardial abnormalities in different clinical settings. This study investigated whether endocardial unipolar voltage mapping of the RVOT detects electroanatomical abnormalities in patients with BrS. Methods and results: Ten asymptomatic patients (8 males, 34...
May 2, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28386822/rapid-mapping-and-differentiation-in-ventricular-outflow-tract-arrhythmia-using-non-contact-mapping
#16
Kazuo Miyazawa, Marehiko Ueda, Yusuke Kondo, Tomohiko Hayashi, Miyo Nakano, Masayuki Ishimura, Masahiro Nakano, Yoshio Kobayashi
PURPOSE: Ventricular outflow tract arrhythmias (VOTAs) can be successfully treated by catheter ablation. However, it is sometimes difficult to differentiate the origin of VOTAs between the right ventricular outflow tract (RVOT) and the other sites, leading to a long fluoroscopy time and unnecessary radiofrequency applications. This study aimed to clarify distinguishable characteristics of the propagation pattern obtained from non-contact mapping (NCM) for VOTA ablation. METHODS: Consecutive 45 patients with VOTAs who underwent catheter ablation using the NCM system were included in this study...
April 6, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28371837/characterization-of-the-arrhythmogenic-substrate-in-patients-with-arrhythmogenic-right-ventricular-cardiomyopathy-undergoing-ventricular-tachycardia-ablation
#17
Senthil Kirubakaran, Caterina Bisceglia, John Silberbauer, Teresa Oloriz, Giulia Santagostino, Miki Yamase, Giuseppe Maccabelli, Nicola Trevisi, Paolo Della Bella
Aims: Arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) is associated with ventricular arrhythmias, even without RV structural disease. We aimed to characterize the RV substrate using electroanatomical mapping and to define outcomes following ventricular tachycardia (VT) ablation in patients with and without RV structural abnormalities. Methods and results: Twenty-nine patients with definite or suspected ARVC undergoing VT ablation were classified as 'electrical' and 'structural' cardiomyopathy based on the absence or presence of major structural criteria...
June 1, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28321025/one-year-success-rate-of-pulmonary-vein-isolation-using-a-novel-irrigated-multipolar-mapping-and-ablation-catheter-with-reduced-power-settings
#18
Dong-In Shin, Jan-Erik Guelker, Christian Blockhaus, Jan Schmidt, Muhammed Kurt, Lukas Clasen, Patrick Mueller, Lars Bansemir, Christoph Brinkmeyer, Alexander Bufe, Malte Kelm, Hisaki Makimoto
The use of a novel irrigated multipolar ablation and mapping catheter for pulmonary vein isolation in patients with atrial fibrillation (AF) has demonstrated reasonable acute success rates and short procedure times, however, long-term outcome data are limited. The aim of this study was to analyze the long-term efficacy of this novel ablation system utilizing a reduced power setting for safety purposes.A total of 89 patients with paroxysmal (63 of 89 patients; 71%) or persistent AF underwent PVI with a reduced power setting of maximum 20 Watts (W) unipolar radiofrequency energy and 30 seconds in duration...
April 6, 2017: International Heart Journal
https://www.readbyqxmd.com/read/28269147/electrocardiogram-reconstruction-from-high-resolution-voltage-optical-mapping
#19
Ilija Uzelac, Conner Herndon, James Farmer, Flavio Fenton
Electrocardiogram recordings during opucal mapping experiments in heart tissue are commonly used tu monitor the health of the preparation and to obtain dominant frequencies during arrhythmic and defibrillatory studies. However the use of ECG reconstructed from optical mapping is seldom used and to date it has not been strictly validated. In this manuscript we present the first detailed validation and comparison of Optical Mapping ECG, or OM-ECG, with standard ECG recordings by calculating the electrostatic potential in space as a function of the voltage measured optically and describe the different approximations that can be used to obtain unipolar or bipolar ECG recordings...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28236155/cardiac-magnetic-resonance-imaging-and-electroanatomic-voltage-discordance-in-non-ischemic-left-ventricle-ventricular-tachycardia-and-premature-ventricular-depolarizations
#20
Brian P Betensky, Wei Dong, Benjamin A D'Souza, Erica S Zado, Yuchi Han, Francis E Marchlinski
PURPOSE: Magnetic resonance imaging (MRI) with late gadolinium enhancement is commonly performed in patients with non-ischemic LV ventricular tachycardia/ventricular premature depolarizations (non-ischemic LV-VT/VPDs) to define VT substrate prior to catheter ablation. We investigated the prevalence of abnormal voltage and VT localized to areas of the myocardium not reported to have late gadolinium enhancement (LGE) on routine pre-procedural MRI and sought to determine if quantitative MRI analysis could reduce this discordance...
June 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
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