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https://www.readbyqxmd.com/read/29341322/isthmus-sites-identified-by-ripple-mapping-are-usually-anatomically-stable-a-novel-method-to-guide-atrial-substrate-ablation
#1
Vishal Luther, Norman Qureshi, Phang Boon Lim, Michael Koa-Wing, Shahnaz Jamil-Copley, Fu Siong Ng, Zachary Whinnett, D Wyn Davies, Nicholas S Peters, Prapa Kanagaratnam, Nick Linton
BACKGROUND: Post ablation reentrant ATs depend upon conducting isthmuses bordered by scar. Bipolar voltage maps highlight scar as sites of low voltage, but the voltage amplitude of an electrogram depends upon the myocardial activation sequence. Furthermore, a voltage threshold that defines atrial scar is unknown. We used Ripple Mapping (RM) to test whether these isthmuses were anatomically fixed between different activation vectors and atrial rates. METHODS: We studied post-AF ablation ATs where > 1 rhythm was mapped...
January 17, 2018: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/29338326/diabetes-mellitus-and-atrial-remodelling-in-patients-with-paroxysmal-atrial-fibrillation-role-of-electroanatomical-mapping-and-catheter-ablation
#2
Domenico Grieco, Zefferino Palamà, Alessio Borrelli, Ermenegildo De Ruvo, Luigi Sciarra, Antonio Scarà, Emilia Goanta, Vito Calabrese, Paolo Pozzilli, Germano Di Sciascio, Leonardo Calò
Complex fractionated atrial electrograms (CFAEs) are related to atrial fibrosis, but their ablation has not yet shown superiority. The aim of the study was to compare, in terms of clinical outcome, two strategies of paroxysmal atrial fibrillation (AF) ablation in patients with type 1 diabetes mellitus (DM): pulmonary vein isolation (PVI) vs. PVI + CFAEs. Compared to an historical population of patient with paroxysmal AF and without DM, a higher percentage of patients with DM showed more than 25% of atrial area interested by CFAEs (study population, 58% vs historical group, 15%; p < 0...
January 1, 2018: Diabetes & Vascular Disease Research
https://www.readbyqxmd.com/read/29330332/identification-and-characterization-of-sites-where-persistent-atrial-fibrillation-is-terminated-by-localized-ablation
#3
Junaid A B Zaman, William H Sauer, Mahmood I Alhusseini, Tina Baykaner, Ryan T Borne, Christopher A B Kowalewski, Sonia Busch, Paul C Zei, Shirley Park, Mohan N Viswanathan, Paul J Wang, Johannes Brachmann, David E Krummen, John M Miller, Wouter Jan Rappel, Sanjiv M Narayan, Nicholas S Peters
BACKGROUND: The mechanisms by which persistent atrial fibrillation (AF) terminates via localized ablation are not well understood. To address the hypothesis that sites where localized ablation terminates persistent AF have characteristics identifiable with activation mapping during AF, we systematically examined activation patterns acquired only in cases of unequivocal termination by ablation. METHODS AND RESULTS: We recruited 57 patients with persistent AF undergoing ablation, in whom localized ablation terminated AF to sinus rhythm or organized tachycardia...
January 2018: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/29317972/high-density-mapping-in-ventricular-tachycardia-ablation-a-pentaray%C3%A2-study
#4
Petra Maagh, Arnd Christoph, Henning Dopp, Markus Sebastian Mueller, Gunnar Plehn, Axel Meissner
Background: High-density mapping of ventricular tachycardia (VT) with PentaRay® (Biosense-Webster) provides high resolution with discrimination of local abnormal electrograms and slow conducting channels. We evaluate the feasibility of PentaRay® to characterize the anatomical substrate and assume an influence of the outcome despite limitations. Methods: Over a 24-month period, 26 endocardial and four epicardial maps were obtained of 26 VT patients (18 ischemic cardiomyopathy (ICM, 69...
December 2017: Cardiology Research
https://www.readbyqxmd.com/read/29286395/benefits-of-cardiac-resynchronization-therapy-in-an-asynchronous-heart-failure-model-induced-by-left-bundle-branch-ablation-and-rapid-pacing
#5
Jingfeng Wang, Zhenning Nie, Haiyan Chen, Xianhong Shu, Zhaohua Yang, Ruiming Yao, Yangang Su, Junbo Ge
It is now well recognized that heart failure (HF) patients with left bundle branch block (LBBB) derive substantial clinical benefits from cardiac resynchronization therapy (CRT), and LBBB has become one of the important predictors for CRT response. The conventional tachypacing-induced HF model has several major limitations, including absence of stable LBBB and rapid reversal of left ventricular (LV) dysfunction after cessation of pacing. Hence, it is essential to establish an optimal model of chronic HF with isolated LBBB for studying CRT benefits...
December 11, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29274899/repolarization-in-perfused-myocardium-predicts-reperfusion-ventricular-tachyarrhythmias
#6
Olesya G Bernikova, Ksenia A Sedova, Natalia V Arteyeva, Aleksey O Ovechkin, Sergey N Kharin, Dmitry N Shmakov, Jan E Azarov
BACKGROUND: Aim of the study was to find out which myocardial repolarization parameters predict reperfusion ventricular tachycardia and fibrillation (VT/VF) and determine how these parameters express in ECG. METHODS: Coronary occlusion and reperfusion (30/30min) was induced in 24 cats. Local activation and end of repolarization times (RT) were measured in 88 intramyocardial leads. Computer simulations of precordial electrograms were performed. RESULTS: Reperfusion VT/VF developed in 10 animals...
December 6, 2017: Journal of Electrocardiology
https://www.readbyqxmd.com/read/29250291/clinical-role-of-dominant-frequency-measurements-in-atrial-fibrillation-ablation-a-systematic-review
#7
Lucaz Gadenz, Javad Hashemi, Mohammad Hassan Shariat, Lorne Gula, Damian P Redfearn
Introduction: Experimental data strongly supports a role for high-frequency sources in the perpetuation of atrial fibrillation, it follows that identification of areas exhibiting spectra containing high dominant frequencies (DF) may represent perpetuating sources and targeted elimination might terminate AF. The aim of this review is to present and critically appraise the literature on DF studied in association with AF ablation. Methods And Results: A systematic review was done including the PubMed (MEDLINE), Cochrane Central Register of Controlled Trials (Central), Scientific Electronic Library Online (SciELO), and HighWire Press databases...
April 2017: Journal of Atrial Fibrillation
https://www.readbyqxmd.com/read/29250264/comparison-of-initial-la-patterns-as-the-road-to-successful-endocardial-box-lesion-ablation
#8
Aleksei S Kovalev, Leo A Bockeria, Andrey G Filatov
Atrial fibrillation (AF) is the most common arrhythmia in the population. Still there is no unity in understanding of mechanisms and their influence on catheter ablation results. In our study we tried to evaluate accurate initial quantitative indicators of electromechanical remodeling that can border patients from expected good to expected poor results of catheter ablation. We performed electroanatomical mapping and ablation procedures in 94 patient (45 female) in 2012 with 3-year follow-up period. The target points were left atria surface area, complex fragmentation atrial electrograms (CFAE) duration and surface area...
February 2017: Journal of Atrial Fibrillation
https://www.readbyqxmd.com/read/29250231/laser-catheter-ablation-of-long-lasting-persistent-atrial-fibrillation-longterm-results
#9
Helmut Weber, Michaela Sagerer-Gerhardt, Armin Heinze
Catheter ablation of atrial fibrillation (AF) is a current therapeutic option but its efficacy for the treatment of long-lasting persistent AF (l-lpAF) remains suboptimal. We tested the laser method as an alternative for catheter ablation of l-lpAF by using an open-irrigated electrode laser mapping and ablation (ELMA) catheter. Laser ablation was attempted in 48 patients aged 50-81 years (69 ± 7.6 y, female = 28) with drug resistant (3.5 trials) l-lpAF (≥12 months). All of the patients had comorbidities: congestive heart failure NYHA II-III (100%), hypertension 29 (60%), coronary artery disease 19 (40%), and heart valve defect 17 (35%)...
August 2017: Journal of Atrial Fibrillation
https://www.readbyqxmd.com/read/29246830/relative-timing-of-near-field-and-far-field-electrograms-can-determine-tachyarrhythmia-site-of-origin
#10
Jane Caldwell, Lorne Gula, Fariha Sadiq Ali, Rodrigo I Miranda, Hoshiar Abdollah, Adrian Baranchuk, Kevin Michael, Christopher Simpson, Damian P Redfearn
BACKGROUND: Despite improving algorithms, inappropriate shocks for supraventricular arrhythmias (SVT) still occur in a significant number of patients with implantable cardioverter defibrillators (ICD). This makes the discovery of novel discriminators that use existing ICD hardware, an attractive proposition. OBJECTIVE: We hypothesised that the delay of activation onset from the device detected, far field electrogram(EGM) to the near field, bipole EGM would allow differentiation of ventricular tachycardias (VT) from SVTs...
December 12, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/29242053/automatic-activation-mapping-and-origin-identification-of-idiopathic-outflow-tract-ventricular-arrhythmias
#11
Alejandro Alcaine, David Soto-Iglesias, Juan Acosta, Viatcheslav Korshunov, Diego Penela, Mikel Martínez, Markus Linhart, David Andreu, Juan Fernández-Armenta, Pablo Laguna, Juan Pablo Martínez, Oscar Camara, Antonio Berruezo
PURPOSE: Activation mapping is used to guide ablation of idiopathic outflow tract ventricular arrhythmias (OTVAs). Isochronal activation maps help to predict the site of origin (SOO): left vs right outflow tract (OT). We evaluate an algorithm for automatic activation mapping based on the onset of the bipolar electrogram (EGM) signal for predicting the SOO and the effective ablation site in OTVAs. METHODS: Eighteen patients undergoing ablation due to idiopathic OTVAs were studied (12 with left ventricle OT origin)...
October 27, 2017: Journal of Electrocardiology
https://www.readbyqxmd.com/read/29238755/spatiotemporal-progression-of-early-human-ventricular-fibrillation
#12
David Vidmar, David E Krummen, Justin Hayase, Sanjiv M Narayan, Gordon Ho, Wouter-Jan Rappel
Objectives: The objective of this study was to evaluate the spatio-temporal organization and progression of human ventricular fibrillation (VF) in the left (LV) and right (RV) ventricles. Background: Studies suggest that localized sources contribute to VF maintenance, but the evolution of VF episodes has not been quantified. Methods: Synchrony between electrograms recorded from 25 patients with induced VF is computed and used to define the Asynchronous Index (ASI), indicating regions which are out-of-step with surrounding tissue...
December 11, 2017: JACC. Clinical Electrophysiology
https://www.readbyqxmd.com/read/29226896/recovery-of-cardiomyopathy-induced-by-ventricular-premature-beats-of-parahisian-origin-after-successful-radiofrequency-catheter-ablation
#13
Gökhan Aksan, Ali Elitok, Mehmet Tezcan, Ahmet Kaya Bilge, Kamil Adalet
A 51-year-old male patient presented with frequent and symptomatic premature ventricular complexes (PVCs) that had induced cardiomyopathy. Radiofrequency (RF) catheter ablation of the origin of the PVCs was planned and the patient underwent electrophysiological study. During activation mapping, the earliest ventricular activation was identified at the His bundle region. Small His bundle electrogram recording by the distal ablation electrode during sinus rhythm revealed that the earliest ventricular activation during PVC preceded the QRS onset by 58 milliseconds...
December 2017: Türk Kardiyoloji Derneği Arşivi: Türk Kardiyoloji Derneğinin Yayın Organıdır
https://www.readbyqxmd.com/read/29223114/regional-conduction-velocity-calculation-from-clinical-multichannel-electrograms-in-human-atria
#14
Bhawna Verma, Tobias Oesterlein, Axel Loewe, Armin Luik, Claus Schmitt, Olaf Dössel
BACKGROUND: During atrial fibrillation, heterogeneities and anisotropies result in a chaotic propagation of the depolarization wavefront. The electrophysiological parameter called conduction velocity (CV) influences the propagation pattern over the atrium. We present a method that determines the regional CV for deformed catheter shapes, which result due to the catheter movement and changing wall contact. METHODS: The algorithm selects stable catheter positions, finds the local activation times (LAT), considers the wall contact and calculates all CV estimates within the area covered by the catheter...
November 26, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/29214421/interpreting-activation-mapping-of-atrial-fibrillation-a-hybrid-computational-physiological-study
#15
Francisco Sahli Costabal, Junaid A B Zaman, Ellen Kuhl, Sanjiv M Narayan
Atrial fibrillation is the most common rhythm disorder of the heart associated with a rapid and irregular beating of the upper chambers. Activation mapping remains the gold standard to diagnose and interpret atrial fibrillation. However, fibrillatory activation maps are highly sensitive to far-field effects, and often disagree with other optical mapping modalities. Here we show that computational modeling can identify spurious non-local components of atrial fibrillation electrograms and improve activation mapping...
December 6, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/29208256/combined-cryoballoon-and-radiofrequency-ablation-versus-radiofrequency-ablation-alone-for-long-standing-persistent-atrial-fibrillation
#16
COMPARATIVE STUDY
Tümer Erdem Guler, Tolga Aksu, Kivanc Yalin, Sukriye Ebru Golcuk, Ferit Onur Mutluer, Serdar Bozyel
BACKGROUND: To achieve sinus rhythm, ablation of long-standing persistent atrial fibrillation (LSPAF) usually requires substrate modification in addition to pulmonary vein isolation (PVI). In the present article, we aimed to compare clinical and substrate modification effects of 2 distinct PVI strategies during stepwise ablation in patients with LSPAF: (1) Combined approach: cryoballoon (CB) for PVI and radiofrequency (RF) ablation for substrate modification and (2) RF-only approach: RF ablation for both PVI and substrate modification...
December 2017: American Journal of the Medical Sciences
https://www.readbyqxmd.com/read/29204352/fractionated-electrograms-with-st-segment-elevation-recorded-from-the-human-right-ventricular-outflow-tract
#17
Edward J Vigmond, Igor R Efimov, Stacey L Rentschler, Ruben Coronel, Bastiaan J Boukens
No abstract text is available yet for this article.
November 2017: HeartRhythm Case Reports
https://www.readbyqxmd.com/read/29197657/feasibility-of-extravascular-pacing-with-a-novel-substernal-electrode-configuration-the-substernal-pacing-acute-clinical-evaluation-study
#18
Darius P Sholevar, Stanley Tung, Vikas Kuriachan, Peter Leong-Sit, Henri Roukoz, Gregory Engel, Steven P Kutalek, Devender Akula, Amy E Thompson, Melissa G T Christie, Marina Ostanniy, Franck Molin
BACKGROUND: Subcutaneous implantable cardioverter-defibrillators provide an alternative to transvenous defibrillation but require higher shock outputs and offer no antitachycardia pacing. The Substernal Pacing Acute Clinical Evaluation (SPACE) study evaluated the feasibility of pacing from an extravascular substernal location. OBJECTIVES: The primary purpose of the SPACE study was to characterize pacing from the substernal space. Secondary objectives included evaluating extracardiac stimulation and recording electrograms...
December 2, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/29194653/electrophysiological-markers-predicting-impeding-av-block-during-ablation-of-atrioventricular-nodal-re-entry-tachycardia
#19
Nikolaos Fragakis, Lydia Krexi, Panagiota Kyriakou, Melani Sotiriadou, Charalambos Lazaridis, Athanasios Karamanolis, Panagiotis Dalampyras, Stelios Tsakiroglou, Vassilios Skeberis, Dimitrios Tsalikakis, Vassilios Vassilikos
BACKGROUND: Radiofrequency (RF) ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is occasionally complicated with atrioventricular block (AVB) often predicted by junctional beats (JB) with loss of ventriculo-atrial (VA) conduction. METHODS: We analysed retrospectively 153 patients undergoing ablation of SP for typical AVNRT. Patients were divided into two age groups: 127 ≤70 years and 26 > 70 years. We analysed the interval between the atrial electrogram in the His-bundle position and the distal ablation catheter [A(H)-A(RFd)] and the proximal coronary sinus catheter [A(RFd)-A(CS)] before RF applications with and without JB...
November 30, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/29187667/strategy-and-outcome-of-catheter-ablation-for-persistent-atrial-fibrillation%C3%A3-impact-of-progress-in-the-mapping-and-ablation-technologies
#20
Hideharu Okamatsu, Ken Okumura
Pulmonary vein (PV) antrum isolation (PVAI) is effective in treating paroxysmal atrial fibrillation (AF) but is less so for persistent AF. A recent randomized study on the ablation strategies for persistent AF demonstrated that 2 common atrial substrate modifications, creation of linear lesions in the left atrium and ablation of complex fractionated electrogram sites, in addition to PVAI did not improve the outcome compared with stand-alone PVAI, suggesting the necessity of a more individualized, selective approach to persistent AF...
November 30, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
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