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QRS morphology

Jeevan K Pant, Sridhar Krishnan
OBJECTIVE: To present a new compressive sensing (CS)-based method for the acquisition of ECG signals and for robust estimation of heart-rate variability (HRV) parameters from compressively sensed measurements with high compression ratio. APPROACH: CS is used in the biosensor to compress the ECG signal. Estimation of the locations of QRS segments is carried out by applying two algorithms on the compressed measurements. The first algorithm reconstructs the ECG signal by enforcing a block-sparse structure on the first-order difference of the signal, so the transient QRS segments are significantly emphasized on the first-order difference of the signal...
March 15, 2018: Physiological Measurement
Taihei Itoh, Takumi Yamada
INTRODUCTION: Preferential conduction from an origin to breakout sites can occur during ventricular arrhythmias (VAs) originating from the left ventricular papillary muscles (LVPMs). The purpose of this study was to investigate the incidence, electrophysiological characteristics, and relevance to radiofrequency catheter ablation (RFCA) of such a preferential conduction demonstrated by pace mapping. METHODS AND RESULTS: We studied 34 consecutive patients undergoing RFCA of 40 LVPM VAs...
March 14, 2018: Journal of Cardiovascular Electrophysiology
Sebastian Polak, Barbara Wiśniowska, Aleksander Mendyk, Adam Pacławski, Jakub Szlęk
Human heart electrophysiology is complex biological phenomenon, which is indirectly assessed by the measured ECG signal. ECG trace is further analyzed to derive interpretable surrogates including QT interval, QRS complex, PR interval, and T wave morphology. QT interval and its modification are the most commonly used surrogates of the drug triggered arrhythmia, but it is known that the QT interval itself is determined by other nondrug related parameters, physiological and pathological. In the current study, we used the computational intelligence algorithms to analyze correlations between various simulated physiological parameters and QT interval...
2018: Computational and Mathematical Methods in Medicine
Guoliang Li, Ardan M Saguner, Deniz Akdis, Guy H Fontaine
Atrioventricular (AV) block has been extensively studied. However, conduction inside the myocardium in patients with AV block has not been reported. In this study, we aimed to demonstrate the presence of intramyocardial block in patients with AV block. Five consecutive patients with spontaneous high-grade AV block and Torsades de pointes (TdP) were prospectively studied with standard United States Catheter Instruments (USCI) endocardial temporary catheter located at the right ventricle (RV) apex. The morphology of endocardial potentials observed in the basic QRS complexes as well as during episodes of TdP was studied...
March 7, 2018: Journal of Investigative Medicine: the Official Publication of the American Federation for Clinical Research
Jan De Pooter, Victor Kamoen, Milad El Haddad, Roland Stroobandt, Marc De Buyzere, Luc Jordaens, Frank Timmermans
BACKGROUND: Female patients are underrepresented in cardiac resynchronization therapy (CRT) trials, although they show better CRT response compared to males and at shorter QRS durations. We hypothesized that differences in left bundle branch block (LBBB) characteristics and mechanical dyssynchrony might explain this gender disparity. METHODS: Patients presenting with true LBBB-morphology (including mid-QRS notching) on surface electrocardiograms (ECG) were selected...
April 15, 2018: International Journal of Cardiology
Angelo Auricchio, Ward A Heggermont
Cardiac resynchronization therapy (CRT) is a well-established treatment for symptomatic heart failure patients with reduced left ventricular ejection fraction, prolonged QRS duration, and abnormal QRS morphology. The ultimate goals of modern CRT are to improve the proportion of patients responding to CRT and to maximize the response to CRT in patients who do respond. While the rate of CRT nonresponders has moderately but progressively decreased over the last 20 years, mostly in patients with left bundle branch block, in patients without left bundle branch block the response rate is almost unchanged...
February 14, 2018: Revista Española de Cardiología
Zhuo Liang, Wang Yunlong, Tao Zhang, Zhihong Han, Jianzeng Dong, Xuejun Ren
BACKGROUND: There is a close anatomical relationship between aortic sinus cusp (ASC) and the left pulmonary sinus cusp (LPSC). PURPOSE: The study was to investigate the significance of mapping and ablation of LPSC for VAs with QRS morphology resembling that of ASC arrhythmias. METHODS: In 33 consecutive patients undergoing successful catheter ablation of idiopathic VAs with ASC arrhythmia-like QRS morphology, LPSC was mapped carefully. RESULTS: Among the 33 patients studied, QRS morphology resembled that of arrhythmias of either right or left coronary cusp (LCC or RCC) origin in 17 and 16 patients, respectively...
February 15, 2018: Journal of Cardiovascular Electrophysiology
Shozo Konishi, Hitoshi Minamiguchi, Kentaro Ozu, Hiroya Mizuno, Shungo Hikoso, Osamu Yamaguchi, Yasushi Sakata
Subcutaneous implantable cardioverter-defibrillators (S-ICDs) are susceptible to T-wave oversensing (TWOS) caused by high rate-dependent QRS-T morphology changes. We experienced an inappropriate S-ICD shock due to TWOS, which could not be predicted by routine exercise testing. A newly available high-pass filter might be effective for avoiding this.
February 2018: Clinical Case Reports
Krishna Kumar Mohanan Nair, Narayanan Namboodiri, Hiren Kevadiya, Ajitkumar Valaparambil
A 35-year old lady was referred for evaluation of recurrent palpitation. During one of the episodes of palpitation a wide QRS tachycardia with left bundle branch block (LBBB) morphology was recorded and it was terminated with intravenous adenosine. The surface electrocardiogram during sinus rhythm did not show any pre-excitation. Echocardiogram was normal. Patient underwent an electrophysiology study after informed consent. During catheter placement a wide QRS tachycardia with LBBB morphology and left axis deviation (LAD) similar to the clinical tachycardia got induced (Fig:1)...
February 14, 2018: Pacing and Clinical Electrophysiology: PACE
Yande Xiang, Zhitao Lin, Jianyi Meng
BACKGROUND: The QRS complex is the most noticeable feature in the electrocardiogram (ECG) signal, therefore, its detection is critical for ECG signal analysis. The existing detection methods largely depend on hand-crafted manual features and parameters, which may introduce significant computational complexity, especially in the transform domains. In addition, fixed features and parameters are not suitable for detecting various kinds of QRS complexes under different circumstances. METHODS: In this study, based on 1-D convolutional neural network (CNN), an accurate method for QRS complex detection is proposed...
January 29, 2018: Biomedical Engineering Online
Qi Zhao, Ruoxi Zhang, Jingbo Hou, Bo Yu
Background: To investigate the relationship between the presence of fragmented QRS (fQRS) on electrocardiogram (ECG) and plasma NT-proBNP levels in patients with ST-elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI). The in-hospital prognostic value of the presence of fQRS was also assessed. Methods: In this retrospective study, 216 patients with STEMI who were undergoing primary PCI were included. fQRS was identified in ECG following primary PCI...
January 2018: Acta Cardiologica Sinica
O Kittnar, L Riedlbauchová, J Tomis, M LoŽek, A Valeriánová, M Hrachovina, M Mlček, M Huptych, J Janoušek, L Lhotská
Cardiac resynchronization therapy (CRT) has proven efficacious in reducing or even eliminating cardiac dyssynchrony and thus improving heart failure symptoms. However, quantification of mechanical dyssynchrony is still difficult and identification of CRT candidates is currently based just on the morphology and width of the QRS complex. As standard 12-lead ECG brings only limited information about the pattern of ventricular activation, we aimed to study changes produced by different pacing modes on the body surface potential maps (BSPM)...
December 30, 2017: Physiological Research
Edward Sze, Zainab Samad, Allison Dunning, Kristen Bova Campbell, Zak Loring, Brett D Atwater, Karen Chiswell, Joseph A Kisslo, Eric J Velazquez, James P Daubert
BACKGROUND: Patients with left bundle branch block (LBBB) often respond to cardiac resynchronization therapy (CRT) with left ventricular ejection fraction (LVEF) improvement. Guideline-directed medical therapy (GDMT), not CRT, is first-line therapy for patients with reduced LVEF with LBBB. However, there are little data on how patients with reduced LVEF and LBBB respond to GDMT. OBJECTIVES: This study examined patients with cardiomyopathy and sought to assess rates of LVEF improvement for patients with LBBB compared to other QRS morphologies...
January 23, 2018: Journal of the American College of Cardiology
Avishag Laish-Farkash, Avi Sabbag, Michael Glikson, Aharon Glick, Vladimir Khalameizer, Amos Katz, Yoav Michowitz
BACKGROUND: Multiform fascicular tachycardia (FT) was recently described as a ventricular tachycardia (VT) that has a reentrant mechanism using multiple fascicular branches and produces alternate fascicular VT forms. Ablating the respective fascicle may cause a change in the reentrant circuit resulting in a change in morphology. Ablation of the septal fascicle is crucial for successful treatment. OBJECTIVES: To describe four cases of FT in which ablation induced a change in QRS morphologies and aggravated clinical course...
January 2018: Israel Medical Association Journal: IMAJ
Matthew M Kalscheur, Ryan T Kipp, Matthew C Tattersall, Chaoqun Mei, Kevin A Buhr, David L DeMets, Michael E Field, Lee L Eckhardt, C David Page
BACKGROUND: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure patients with reduced left ventricular function and intraventricular conduction delay. However, individual outcomes vary significantly. This study sought to use a machine learning algorithm to develop a model to predict outcomes after CRT. METHODS AND RESULTS: Models were developed with machine learning algorithms to predict all-cause mortality or heart failure hospitalization at 12 months post-CRT in the COMPANION trial (Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure)...
January 2018: Circulation. Arrhythmia and Electrophysiology
Yuki Komatsu, Akihiko Nogami, Yasutoshi Shinoda, Keita Masuda, Takeshi Machino, Kenji Kuroki, Hiro Yamasaki, Yukio Sekiguchi, Kazutaka Aonuma
BACKGROUND: The communicating vein (CV) between the great cardiac vein and small cardiac venous systems passes between the aortic and pulmonary annulus and is located in close association with the left ventricular summit (summit CV). METHODS AND RESULTS: Thirty-one patients with idiopathic ventricular arrhythmias (VAs) underwent mapping of the left ventricular summit by using a 2F microcatheter introduced into the summit CV with coronary sinus venographic guidance...
January 2018: Circulation. Arrhythmia and Electrophysiology
Ashish Kumar, Rama Komaragiri, Manjeet Kumar
With the alarming rise in the deaths due to cardiovascular diseases (CVD), present medical research scenario places notable importance on techniques and methods to detect CVDs. As adduced by world health organization, technological proceeds in the field of cardiac function assessment have become the nucleus and heart of all leading research studies in CVDs in which electrocardiogram (ECG) analysis is the most functional and convenient tool used to test the range of heart-related irregularities. Most of the approaches present in the literature of ECG signal analysis consider noise removal, rhythm-based analysis, and heartbeat detection to improve the performance of a cardiac pacemaker...
January 11, 2018: Journal of Medical Systems
Chao-Feng Chen, Xiao-Hua Liu, Xiao-Fei Gao, Bin Chen, Yi-Zhou Xu
BACKGROUND: Premature ventricular contractions (PVCs) originating from aortic sinus cusps is not infrequent and can be eliminated effectively by radiofrequency ablation with rare complications. However, after a review of the medical literature, and to our knowledge, this is the first case of successful idiopathic aortic sinus cusps-PVC-ablation using a 3-dimensional (3D) mapping system in an adult with dextrocardia. METHODS: A 62-year-old male with dextrocardia and situs inversus underwent catheter ablation of frequent PVCs...
December 2017: Medicine (Baltimore)
Federico Vancheri, Sergio Vancheri, Michael Henein
BACKGROUND AND AIM: QRS amplitude and duration are associated with increased left ventricular (LV) volume, mass and dysfunction. However, the diagnostic concordance between QRS measurements and LV morphology and function, as shown by Doppler echocardiography, is not well established. We investigated the relationships of QRS duration and amplitude with echocardiographic measurements of LV morphology and systolic and diastolic function in normal individuals. METHODS: Individuals without signs or symptoms of coronary artery disease or heart failure, who underwent clinical examination as a part of a cross-sectional survey for the prevalence of coronary risk factors, randomly selected from the population list in Caltanissetta, Italy, were included in the study...
December 27, 2017: Echocardiography
Christopher Reithmann, Michael Fiek
BACKGROUND: Ventricular arrhythmias (VAs) from the left ventricular outflow tract (LVOT) can have multiple exits exhibiting divergent ECG features. METHODS: In a series of 131 patients with VAs with LVOT origin, 10 patients presented with divergent QRS morphologies. Multisite endo- and epicardial mapping of different exit sites was performed. RESULTS: The earliest ventricular activity of 23 LVOT VAs in 10 patients was detected in the endocardium of the LV in 7 patients, the aortic sinuses of Valsalva (SoV) in 3 patients, the distal coronary sinus in 6 patients, the anterior interventricular vein in 3 patients, and the posterior right ventricular outflow tract (RVOT) in 4 patients...
December 27, 2017: Journal of Interventional Cardiac Electrophysiology: An International Journal of Arrhythmias and Pacing
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