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QRS morphology

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https://www.readbyqxmd.com/read/28813535/modeling-hypothermia-induced-effects-for-the-heterogeneous-ventricular-tissue-from-cellular-level-to-the-impact-on-the-ecg
#1
Roland Kienast, Michael Handler, Markus Stöger, Daniel Baumgarten, Friedrich Hanser, Christian Baumgartner
Hypothermia has a profound impact on the electrophysiological mechanisms of the heart. Experimental investigations provide a better understanding of electrophysiological alterations associated with cooling. However, there is a lack of computer models suitable for simulating the effects of hypothermia in cardio-electrophysiology. In this work, we propose a model that describes the cooling-induced electrophysiological alterations in ventricular tissue in a temperature range from 27°C to 37°C. To model the electrophysiological conditions in a 3D left ventricular tissue block it was essential to consider the following anatomical and physiological parameters in the model: the different cell types (endocardial, M, epicardial), the heterogeneous conductivities in longitudinal, transversal and transmural direction depending on the prevailing temperature, the distinct fiber orientations and the transmural repolarization sequences...
2017: PloS One
https://www.readbyqxmd.com/read/28794085/idiopathic-ventricular-arrhythmias-originating-from-the-parietal-band-electrocardiographic-and-electrophysiological-characteristics-and-outcome-of-catheter-ablation
#2
Takumi Yamada, Naoki Yoshida, Taihei Itoh, Silvio H Litovsky, Harish Doppalapudi, H Thomas McElderry, G Neal Kay
BACKGROUNDS: The parietal band is one of the muscle bands in the right ventricle. This study investigated the electrocardiographic and electrophysiological characteristics and ablation outcome of idiopathic ventricular arrhythmias (VAs) originating from the parietal band. METHODS AND RESULTS: We studied 14 patients with idiopathic VA origins in the parietal band among 294 consecutive patients with VA origins in the right ventricle. The QRS morphologies of the parietal band VAs were characterized by a left bundle branch block and left inferior (n=12) or superior (n=2) axis pattern with the presence of a notch in the middle of the QRS in all cases, precordial transition at ≤lead V3 in 7 patients, and a slow QRS onset in 4 patients...
August 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28746519/single-derivation-fragmented-qrs-can-predict-poor-prognosis-in-successfully-revascularized-acute-stemi-patients
#3
Zulkif Tanriverdi, Huseyin Dursun, Tugce Colluoglu, Dayimi Kaya
Background: QRS fragmentation (fQRS) is classically defined as the presence of slurred QRS morphology in at least two contiguous leads, and its prognostic importance has been shown in ST elevation myocardial infarction (STEMI). However, no study has investigated the significance of single lead fQRS (sl-fQRS) in surface electrocardiography (ECG). Objectives: To evaluate whether sl-fQRS is as valuable as classical fQRS in patients with acute STEMI who had successful revascularization with primary percutaneous coronary intervention (pPCI)...
July 20, 2017: Arquivos Brasileiros de Cardiologia
https://www.readbyqxmd.com/read/28705874/automated-quantification-of-low-amplitude-abnormal-qrs-peaks-from-high-resolution-ecg-recordings-predicts-arrhythmic-events-in-patients-with-cardiomyopathy
#4
Moloy Das, Adrian M Suszko, Sachin Nayyar, Karthik Viswanathan, Danna A Spears, George Tomlinson, Arnold Pinter, Eugene Crystal, Rupin Dalvi, Sridhar Krishnan, Vijay S Chauhan
BACKGROUND: Cardiomyopathy patients are at risk of sudden death, typically from scar-related abnormalities of electrical activation that promote ventricular tachyarrhythmias. Abnormal intra-QRS peaks may provide a measure of altered activation. We hypothesized that quantification of such QRS peaks (QRSp) in high-resolution ECGs would predict arrhythmic events in implantable cardioverter-defibrillator (ICD)-eligible cardiomyopathy patients. METHODS AND RESULTS: Ninety-nine patients with ischemic or non-ischemic dilated cardiomyopathy undergoing prophylactic ICD implantation were prospectively enrolled (age 62±11 years, left ventricular ejection fraction 27±7%)...
July 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28695377/ventricular-dyssynchrony-assessment-using-ultra-high-frequency-ecg-technique
#5
Pavel Jurak, Josef Halamek, Jaroslav Meluzin, Filip Plesinger, Tereza Postranecka, Jolana Lipoldova, Miroslav Novak, Vlastimil Vondra, Ivo Viscor, Ladislav Soukup, Petr Klimes, Petr Vesely, Josef Sumbera, Karel Zeman, Roshini S Asirvatham, Jason Tri, Samuel J Asirvatham, Pavel Leinveber
PURPOSE: The aim of this proof-of-concept study is to introduce new high-dynamic ECG technique with potential to detect temporal-spatial distribution of ventricular electrical depolarization and to assess the level of ventricular dyssynchrony. METHODS: 5-kHz 12-lead ECG data was collected. The amplitude envelopes of the QRS were computed in an ultra-high frequency band of 500-1000 Hz and were averaged (UHFQRS). UHFQRS V lead maps were compiled, and numerical descriptor identifying ventricular dyssynchrony (UHFDYS) was detected...
September 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
https://www.readbyqxmd.com/read/28652528/electrophysiological-characteristics-and-radiofrequency-catheter-ablation-treatment-of-idiopathic-ventricular-arrhythmias-successfully-ablated-from-the-ostium-of-the-coronary-sinus
#6
Yoshiaki Yui, Yukio Sekiguchi, Akihiko Nogami, Hiro Yamasaki, Takeshi Machino, Kenji Kuroki, Miyako Igarashi, Kazutaka Aonuma
BACKGROUND: Idiopathic ventricular arrhythmias (VAs) rarely arise from the epicardium at the crux of the heart. However, the electrophysiological characteristics of VAs successfully ablated from the ostium of the coronary sinus (CSO) have not yet been documented.Methods and Results:Electrocardiographic and electrophysiological data were analyzed in patients with idiopathic VAs successfully ablated from the CSO.Among 309 patients with idiopathic VAs treated with radiofrequency catheter ablation (RFCA), 6 (1...
June 23, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/28626904/do-real-world-data-support-and-extend-our-ability-to-predict-reverse-remodelling-following-cardiac-resynchronization-therapy-based-on-qrs-morphology-and-width
#7
EDITORIAL
Torkel Steen, Kenneth Dickstein
No abstract text is available yet for this article.
June 19, 2017: European Journal of Heart Failure
https://www.readbyqxmd.com/read/28613240/an-isoform-of-nedd4-2-plays-a-pivotal-role-in-electrophysiological-cardiac-abnormalities
#8
Shintaro Minegishi, Tomoaki Ishigami, Hisho Kawamura, Tabito Kino, Lin Chen, Rie Nakashima-Sasaki, Hiroshi Doi, Kengo Azushima, Hiromichi Wakui, Yumi Chiba, Kouichi Tamura
We have previously shown that neural precursor cell-expressed developmentally downregulated gene 4-2 (Nedd4-2) isoforms with a C2 domain are closely related to ubiquitination of epithelial sodium channel (ENaC), resulting in salt-sensitive hypertension by Nedd4-2 C2 targeting in mice. The sodium voltage-gated channel alpha subunit 5 (SCN5A) gene encodes the α subunit of the human cardiac voltage-gated sodium channel (I Na), and the potassium voltage-gated channel subfamily H member 2 (KCNH2) gene encodes rapidly activating delayed rectifier K channels (I Kr)...
June 14, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28610987/tracking-interlead-heterogeneity-of-r-and-t-wave-morphology-to-disclose-latent-risk-for-sudden-cardiac-death
#9
Richard L Verrier, Heikki Huikuri
Sudden cardiac death (SCD) due primarily to ventricular fibrillation claims 1.5 million lives worldwide each year. In 45%-50% of cases, it is the first manifestation of underlying heart disease. Traditional risk factors including smoking, hypertension, age, sex, as well as depressed left ventricular ejection fraction lack sufficient sensitivity and specificity to forewarn of impending life-threatening arrhythmias. There has been a decades-long search for electrocardiographic (ECG) markers of SCD risk. Several interval-based indices such as QT dispersion and Tpeak-Tend interval held initial promise but ultimately yielded mixed results...
June 10, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28601711/identification-of-qrs-complex-in-non-stationary-electrocardiogram-of-sick-infants
#10
S Kota, C B Swisher, T Al-Shargabi, N Andescavage, A du Plessis, R B Govindan
BACKGROUND: Due to the high-frequency of routine interventions in an intensive care setting, electrocardiogram (ECG) recordings from sick infants are highly non-stationary, with recurrent changes in the baseline, alterations in the morphology of the waveform, and attenuations of the signal strength. Current methods lack reliability in identifying QRS complexes (a marker of individual cardiac cycles) in the non-stationary ECG. In the current study we address this problem by proposing a novel approach to QRS complex identification...
August 1, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28601028/qrs-complex-detection-in-ecg-signals-using-locally-adaptive-weighted-total-variation-denoising
#11
Tanushree Sharma, Kamalesh Kumar Sharma
The QRS complex is the most prominent feature in the electrocardiogram (ECG), therefore, its detection is required for delineation of other waves and segments in the ECG and derivation of additional clinically useful information. QRS detection is complicated by factors like varying QRS morphologies, noise, artefacts and interference from tall and pointed P- and T-waves. In this paper, we propose a novel technique for QRS detection by preprocessing the ECG using weighted total variation (WTV) denoising. A local estimate of noise in the signal block under consideration is used to determine the regularization parameter in WTV minimization, which determines the amount of smoothing applied...
August 1, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28598506/atrial-overdrive-pacing-during-wide-qrs-tachycardia-with-rbbb-morphology-what-is-the-mechanism
#12
Krishna Kumar Mohanan Nair, Narayanan Namboodiri, Suji Karunakaran, Priya Giridhara, Abhilash Sreevilasam Pushpangadhan, Ajitkumar Valaparambil
No abstract text is available yet for this article.
June 9, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28579124/sinus-tachycardia-with-variable-qrs-morphology
#13
Darrin M Breaux, D Luke Glancy
Wolff-Parkinson-White-type ventricular preexcitation was recognized for the first time in a 67-year-old man four days after aortic valve replacement. The preexcitation was intermittent.
August 1, 2017: American Journal of Cardiology
https://www.readbyqxmd.com/read/28568774/atrial-premature-beat-on-wide-qrs-tachycardia-with-lbbb-morphology-what-is-the-mechanism
#14
Krishna Kumar Mohanan Nair, Narayanan Namboodiri, Priya Giridhara, Sreevilasam Pushpangadhan Abhilash, Ajitkumar Valaparambil
No abstract text is available yet for this article.
June 1, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28549996/effect-of-pr-interval-prolongation-on-long-term-outcomes-in-patients-with-left-bundle-branch-block-vs-non-left-bundle-branch-block-morphologies-undergoing-cardiac-resynchronization-therapy
#15
John Rickard, Mohammad Karim, Bryan Baranowski, Daniel Cantillon, David Spragg, W H Wilson Tang, Mark Niebauer, Richard Grimm, Kevin Trulock, Bruce Wilkoff, Niraj Varma
BACKGROUND: Although the influence of QRS duration (QRSd) and/or bundle branch block morphology on outcomes of cardiac resynchronization therapy (CRT) have been well studied, the effect of PR interval remains uncertain. OBJECTIVE: The purpose of this study was to evaluate the impact of PR prolongation (PRp) before CRT on long-term outcomes, specifically taking into account bundle branch block morphology and QRSd. METHODS: We extracted clinical data on consecutive patients undergoing CRT...
May 24, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28545282/-electrocardiogram-characteristics-of-patients-with-ventricular-arrhythmia-originating-from-the-distal-great-cardiac-vein
#16
R L Zheng, D P Zhou, J X Lin, Y C Li, J Li, J Li, R P Yin, J F Lin
Objective: To explore the electrocardiographic characteristics of patients with idiopathic ventricular arrhythmias (VAs) originating from different portions of distal great cardiac veins (DGCV). Methods: The study included 49 patients underwent successful RFCA of premature ventricular complex(PVCs)/ventricular tachycardia(VT) from different portions of the DGCV in our department from July 2009 to March 2016. The surface 12-lead electrocardiogram (ECG) and intraventricular ablation mapping features were analyzed...
April 24, 2017: Zhonghua Xin Xue Guan Bing za Zhi
https://www.readbyqxmd.com/read/28543265/stricter-criteria-for-left-bundle-branch-block-diagnosis-do-not-improve-response-to-crt
#17
Emanuele Bertaglia, Federico Migliore, Anna Baritussio, Antonio De Simone, Albino Reggiani, Domenico Pecora, Antonio D'Onofrio, Antonio Rapacciuolo, Gianluca Savarese, Attilio Pierantozzi, Biondino Marenna, Franco Ruffa, Monica Campari, Maurizio Malacrida, Giuseppe Stabile
BACKGROUND: Cardiac resynchronization therapy (CRT) has proved to be effective in patients with heart failure and left bundle branch block (LBBB). Recently, new electrocardiography criteria have been proposed for the diagnosis of LBBB. These criteria are stricter than the current American Heart Association (AHA) criteria. We assessed the rate of echocardiographic response to CRT in patients with traditional LBBB versus patients who met the new criteria (strict LBBB). METHODS: Consecutive patients undergoing CRT were enrolled in the CRT MORE registry...
May 23, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28543106/the-concept-of-triple-wavefront-fusion-during-biventricular-pacing-using-the-egm-to-produce-the-best-acute-hemodynamic-improvement-in-crt
#18
Iris A H Ter Horst, Margot D Bogaard, Anton E Tuinenburg, Thomas P Mast, Teun P de Boer, Pieter A F M Doevendans, Mathias Meine
BACKGROUND: Previous reports suggest that biventricular pacing (BiVp) fused with intrinsic conduction (BiVp-fusion, triple wavefront fusion) is associated with improved resynchronization compared to pure-BiVp in cardiac resynchronization therapy (CRT). This study aimed to assess the association between acute hemodynamic benefit of CRT and signs of BiVp-fusion by using a novel electrogram (EGM)-based method. METHODS: In 17 patients undergoing CRT implantation, 28 combinations of atrioventricular (AV) and interventricular (VV) delays were applied while invasively measuring acute hemodynamic response based on maximum rate of left ventricular (LV) pressure rise (LV dP/dtmax ) to assess optimal BiVp settings...
May 23, 2017: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/28538417/clinical-and-electrocardiographic-characteristics-of-infarctional-ventricular-ectopic-beats-an-observational-study
#19
Yuechun Li, Shi Zhe-Wei, Zheng Cheng, Chen Guang-Yi, Zhou De-Pu, Li Xiao-Wei, Guan Xueqiang, Lin Jiafeng, Chen Peng
The purpose of this study was to explore the clinical and electrocardiographic characteristics of infarctional ventricular ectopic beats (IVEBs).Thirty-eight acute myocardial infarction (AMI) patients with IVEB and 109 AMI patients without IVEB were analyzed. The morphological changes of QRS complex, ST segment, and T wave were compared to IVEB with sinus rhythm from the same period and fully evolved phase.An IVEB QRS complex often revealed the right bundle branch block morphology, in addition to Q wave AMI; no-Q wave AMI also had IVEB...
May 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28506214/origins-location-of-the-outflow-tract-ventricular-arrhythmias-exhibiting-qrs-pattern-or-qs-pattern-with-a-notch-on-the-descending-limb-in-lead-v1
#20
Cong Lin, Cheng Zheng, De-Pu Zhou, Xiao-Wei Li, Shu-Jie Wu, Jia-Feng Lin
BACKGROUND: Ventricular outflow tract(VOT) ventricular arrhythmias(VAs) presenting qrS pattern or QS pattern with a notch on the descending limb in lead V1 were consistently thought of arising from the commissure between left and right coronary cusp (L-RCC) by previous studies. However, we found they could originate from other anatomic structures in VOT. This study aimed to investigate the exact origin of this kind VAs. METHODS: Forty-nine patients of VOT premature ventricular contrations/ventricular tachycardia(PVCs/VT) with lead V1 presenting qrS pattern or QS pattern with a notch on the descending limb undergoing successful radiofrequency catheter ablation(RFCA) in our center were analyzed...
May 15, 2017: BMC Cardiovascular Disorders
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