keyword
MENU ▼
Read by QxMD icon Read
search

Unipolar mapping

keyword
https://www.readbyqxmd.com/read/28386822/rapid-mapping-and-differentiation-in-ventricular-outflow-tract-arrhythmia-using-non-contact-mapping
#1
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
#2
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...
March 20, 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
#3
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...
March 17, 2017: International Heart Journal
https://www.readbyqxmd.com/read/28269147/electrocardiogram-reconstruction-from-high-resolution-voltage-optical-mapping
#4
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
#5
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...
February 24, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28227376/electrocardiogram-reconstruction-from-high-resolution-voltage-optical-mapping
#6
Ilija Uzelac, Conner Herndon, James Farmer, Flavio Fenton, Ilija Uzelac, Conner Herndon, James Farmer, Flavio Fenton, 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/28185348/two-independent-mapping-techniques-identify-rotational-activity-patterns-at-sites-of-local-termination-during-persistent-atrial-fibrillation
#7
Mahmood Alhusseini, David Vidmar, Gabriela L Meckler, Christopher A Kowalewski, Fatemah Shenasa, Paul J Wang, Sanjiv M Narayan, Wouter-Jan Rappel
INTRODUCTION: The mechanisms for atrial fibrillation (AF) are unclear in part because diverse mapping techniques yield diverse maps, ranging from stable organized sources to highly disordered waves. We hypothesized that AF mechanisms may be clarified if mapping techniques were compared in the same patients, and referenced to a clinical endpoint. We compared two independent AF mapping techniques in patients in whom ablation terminated persistent AF before pulmonary vein isolation (PVI)...
February 10, 2017: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/28120237/hibernating-substrate-of-ventricular-tachycardia-a-three-dimensional-metabolic-and-electro-anatomic-assessment
#8
Ayman A Hussein, Michelle Niekoop, Vasken Dilsizian, Yousra Ghzally, Mohammed Abdulghani, Ramazan Asoglu, Wengen Chen, Mark Smith, Vincent See, Stephen R Shorofsky, Timm-Michael Dickfeld
PURPOSE: Hibernating myocardium (HM) is associated with sudden cardiac death (SCD). Little is known about the electrophysiological properties of HM and the basis of its association with SCD. We aimed to electrophysiologically characterize HM in patients with ventricular tachycardia (VT). METHODS: Endocardial voltage mapping, metabolic (18)FDG-positron emission tomography (PET) and perfusion (82)Rb, (201)Tl, or (99m)Tc scans were performed in 61 ischemic heart disease patients with VT...
January 25, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28108548/the-effect-of-left-ventricular-pacing-on-transmural-activation-delay-in-myopathic-human-hearts
#9
Andreu Porta-Sánchez, Paul Angaran, Stéphane Massé, Krishnakumar Nair, Talha Farid, Karthikeyan Umapathy, John Asta, Sigfus Gizurarson, Kumaraswamy Nanthakumar
AIMS: Left ventricular (LV) epicardial pacing (LVEpiP) in human myopathic hearts does not decrease global epicardial activation delay compared with right ventricular (RV) endocardial pacing (RVEndoP); however, the effect on transmural activation delay has not been evaluated. To characterize the transmural electrical activation delay in human myopathic hearts during RVEndoP and LVEpiP compared with global epicardial activation delay. METHODS AND RESULTS: Explanted hearts from seven patients (5 male, 46 ± 10 years) undergoing cardiac transplantation were Langendorff-perfused and mapped using an epicardial sock electrode array (112 electrodes) and 25 transmural plunge needles (four electrodes, 2 mm spacing), for a total of 100 unipolar transmural electrodes...
January 20, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28011584/effect-of-anisotropy-on-ventricular-vulnerability-to-unidirectional-block-and-reentry-by-single-premature-stimulation-during-normal-sinus-rhythm-in-rat-heart
#10
S Rossi, A Buccarello, P R Ershler, R L Lux, S Callegari, D Corradi, L Carnevali, A Sgoifo, M Miragoli, E Musso, E Macchi
Single high-intensity premature stimuli when applied to the ventricles during ventricular drive of an ectopic site, as in Winfree's "pinwheel experiment," usually induce reentry arrhythmias in the normal heart, while single low-intensity stimuli barely do. Yet ventricular arrhythmia vulnerability during normal sinus rhythm remains largely unexplored. With a view to define the role of anisotropy on ventricular vulnerability to unidirectional conduction block and reentry, we revisited the pinwheel experiment with reduced constraints in the in situ rat heart...
March 1, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/27932238/gender-differences-in-patients-with-arrhythmogenic-right-ventricular-dysplasia-cardiomyopathy-clinical-manifestations-electrophysiological-properties-substrate-characteristics-and-prognosis-of-radiofrequency-catheter-ablation
#11
Chin-Yu Lin, Fa-Po Chung, Yenn-Jiang Lin, Shih-Lin Chang, Li-Wei Lo, Yu-Feng Hu, Ta-Chuan Tuan, Tze-Fan Chao, Jo-Nan Liao, Yao-Ting Chang, Yun-Yu Chen, Rohit Walia, Abigail Louise D Te, Shinya Yamada, Shih-Ann Chen
BACKGROUND: Gender differences in the penetrance and clinical expression of genetic mutations have been reported in patients with arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C). Our study aimed at clarifying the impact of gender on ventricular substrates and clinical outcomes after radiofrequency catheter ablation (RFCA). METHODS: Patients with ARVD/C underwent RFCA for drug-refractory ventricular arrhythmias (VAs) were consecutively enrolled...
January 15, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/27930354/simultaneous-non-invasive-epicardial-and-endocardial-mapping-in-patients-with-brugada-syndrome-new-insights-into-arrhythmia-mechanisms
#12
Boris Rudic, Maria Chaykovskaya, Alexey Tsyganov, Vitaly Kalinin, Erol Tülümen, Theano Papavassiliu, Christina Dösch, Volker Liebe, Jürgen Kuschyk, Susanne Röger, Ibrahim El-Battrawy, Ibrahim Akin, Marina Yakovleva, Elena Zaklyazminskaya, Anna Shestak, Stanislav Kim, Mikhail Chmelevsky, Martin Borggrefe
BACKGROUND: The underlying mechanisms of Brugada syndrome (BrS) are not completely understood. Recent studies provided evidence that the electrophysiological substrate, leading to electrocardiogram abnormalities and/or ventricular arrhythmias, is located in the right ventricular outflow tract (RVOT). The purpose of this study was to examine abnormalities of epicardial and endocardial local unipolar electrograms by simultaneous noninvasive mapping in patients with BrS. METHODS AND RESULTS: Local epicardial and endocardial unipolar electrograms were analyzed using a novel noninvasive epi- and endocardial electrophysiology system (NEEES) in 12 patients with BrS and 6 with right bundle branch block for comparison...
November 14, 2016: Journal of the American Heart Association
https://www.readbyqxmd.com/read/27921187/rotor-tracking-using-phase-of-electrograms-recorded-during-atrial-fibrillation
#13
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...
April 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/27906655/methodology-considerations-in-phase-mapping-of-human-cardiac-arrhythmias
#14
Ramya Vijayakumar, Sunil K Vasireddi, Phillip S Cuculich, Mitchell N Faddis, Yoram Rudy
BACKGROUND: Phase analysis of cardiac arrhythmias, particularly atrial fibrillation, has gained interest because of the ability to detect organized stable drivers (rotors) and target them for therapy. However, the lack of methodology details in publications on the topic has resulted in ongoing debate over the phase mapping technique. By comparing phase maps and activation maps, we examined advantages and limitations of phase mapping. METHODS AND RESULTS: Seven subjects were enrolled...
November 2016: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/27870970/panoramic-characterization-of-endocardial-left-atrial-activation-during-human-persistent-af-insights-from-non-contact-mapping
#15
Geoffrey Lee, Alex J A McLellan, Ross J Hunter, Matthew J Lovell, Malcolm Finlay, Waqas Ullah, Mehul B Dhinoja, Simon Sporton, Mark J Earley, Richard J Schilling
BACKGROUND: The relative importance of focal drivers, multiple wavelets, rotors and endocardial-epicardial circuits in the maintenance of persistent AF remains unclear. Our objective was to characterize AF wavefront (WF) dynamics during persistent AF. METHODS: The Ensite 3000 (St Jude Medical) non-contact mapping system was used to map the LA of 15 patients with persistent AF. Wavefronts were classified into planar WFs, rotors or focal WFs. For each new WF the site of origin, the unipolar electrogram, and propagation patterns were determined...
February 1, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/27766704/treatment-of-recurrent-nonparoxysmal-atrial-fibrillation-using-focal-impulse-and-rotor-mapping-firm-guided-rotor-ablation-early-recurrence-and-long-term-outcomes
#16
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
https://www.readbyqxmd.com/read/27737802/cardiac-activation-repolarization-patterns-and-ion-channel-expression-mapping-in-intact-isolated-normal-human-hearts
#17
Tobias Opthof, Carol Ann Remme, Esther Jorge, Francisco Noriega, Rob F Wiegerinck, Arlin Tasiam, Leander Beekman, Jesus Alvarez-Garcia, Cristian Munoz-Guijosa, Ruben Coronel, Juan Cinca
BACKGROUND: The repolarization pattern of the human heart is unknown. OBJECTIVE: The purpose of this study was to perform a multisite analysis of the activation-repolarization patterns and mRNA expression patterns of ion channel subunits in isolated human hearts. METHODS: Hearts from 3 donors without reported cardiac disease were Langendorff perfused with the patient's own blood. A standard ECG was obtained before explantation. Up to 92 unipolar electrograms from 24 transmural needles were obtained during right atrial pacing...
October 11, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/27663606/a-novel-approach-for-left-ventricular-lead-placement-in-cardiac-resynchronization-therapy-intraprocedural-integration-of-coronary-venous-electroanatomic-mapping-with-delayed-enhancement-cardiac-magnetic-resonance-imaging
#18
Uyên Châu Nguyên, Masih Mafi-Rad, Jean-Paul Aben, Martijn W Smulders, Elien B Engels, Antonius M W van Stipdonk, Justin G L M Luermans, Sebastiaan C A M Bekkers, Frits W Prinzen, Kevin Vernooy
BACKGROUND: Placing the left ventricular (LV) lead at a site of late electrical activation remote from scar is desired to improve cardiac resynchronization therapy (CRT) response. OBJECTIVE: The purpose of this study was to integrate coronary venous electroanatomic mapping (EAM) with delayed enhancement cardiac magnetic resonance (DE-CMR) enabling LV lead guidance to the latest activated vein remote from scar. METHODS: Eighteen CRT candidates with focal scar on DE-CMR were prospectively included...
January 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/27547135/association-between-high-endocardial-unipolar-voltage-and-improved-left-ventricular-function-in-patients-with-ischemic-cardiomyopathy
#19
Ki Park, Dejian Lai, Eileen M Handberg, Lem Moyé, Emerson C Perin, Carl J Pepine, R David Anderson
We know that endocardial mapping reports left ventricular electrical activity (voltage) and that these data can predict outcomes in patients undergoing traditional revascularization. Because the mapping data from experimental models have also been linked with myocardial viability, we hypothesized an association between increased unipolar voltage in patients undergoing intramyocardial injections and their subsequent improvement in left ventricular performance. For this exploratory analysis, we evaluated 86 patients with left ventricular dysfunction, heart-failure symptoms, possible angina, and no revascularization options, who were undergoing endocardial mapping...
August 2016: Texas Heart Institute Journal
https://www.readbyqxmd.com/read/27516464/directional-influences-of-ventricular-activation-on-myocardial-scar-characterization-voltage-mapping-with-multiple-wavefronts-during-ventricular-tachycardia-ablation
#20
Roderick Tung, Mark E Josephson, Jason S Bradfield, Kalyanam Shivkumar
BACKGROUND: The effects of varying the wavefront of activation on ventricular scar characterization has not been systematically assessed. METHODS AND RESULTS: Patients referred for ablation of scar-related ventricular tachycardia underwent voltage maps during a minimum of 2 wavefronts of activation. The bipolar and unipolar low-voltage areas were compared, and direct electrogram analysis was performed in regions where discrepancies were seen. Concordance between wavefronts was measured by calculating percentage of overlap between maps...
August 2016: Circulation. Arrhythmia and Electrophysiology
keyword
keyword
32046
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"