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Vectorcardiogram

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https://www.readbyqxmd.com/read/27742061/detection-of-elevated-pulmonary-pressures-by-the-ecg-derived-ventricular-gradient-a-comparison-of-conversion-matrices-in-patients-with-suspected-pulmonary-hypertension
#1
Marlieke L A Haeck, Gijsbert F L Kapel, Roderick W C Scherptong, Cees A Swenne, Arie C Maan, Jeroen J Bax, Martin J Schalij, Hubert W Vliegen
BACKGROUND: The aim was to assess the diagnostic value of the Inverse Dower (INVD)-derived vectorcardiogram (VCG) and the Kors-derived VCG to detect elevated systolic pulmonary artery pressure (SPAP) in suspected pulmonary hypertension (PH). METHODS: In 132 patients, morphologic variables were evaluated by comparing the VCG parameters synthesized by INVD and Kors matrix. Comparison of the diagnostic accuracy of detecting SPAP ≥50mmHg between the matrices was performed by ROC curve analysis and logistic regression analysis...
September 8, 2016: Journal of Electrocardiology
https://www.readbyqxmd.com/read/27723506/self-organizing-visualization-and-pattern-matching-of-vectorcardiographic-qrs-waveforms
#2
Hui Yang, Fabio Leonelli
QRS morphology is commonly used in the electrocardiographic diagnosis of ventricular depolarization such as left bundle branch block (LBBB) and ventricular septal infarction. We investigated whether pattern matching of QRS loops in the 3-dimensional vectorcardiogram (VCG) will improve the grouping of patients whose space-time electrical activity akin to each other, thereby assisting in clinical decision making. First, pattern dissimilarity of VCG QRS loops is qualitatively measured and characterized among patients, resulting in a 93×93 distance matrix of patient-to-patient dissimilarity...
September 28, 2016: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/27230674/why-qrs-duration-should-be-replaced-by-better-measures-of-electrical-activation-to-improve-patient-selection-for-cardiac-resynchronization-therapy
#3
REVIEW
Elien B Engels, Masih Mafi-Rad, Antonius M W van Stipdonk, Kevin Vernooy, Frits W Prinzen
Cardiac resynchronization therapy (CRT) is a well-known treatment modality for patients with a reduced left ventricular ejection fraction accompanied by a ventricular conduction delay. However, a large proportion of patients does not benefit from this therapy. Better patient selection may importantly reduce the number of non-responders. Here, we review the strengths and weaknesses of the electrocardiogram (ECG) markers currently being used in guidelines for patient selection, e.g., QRS duration and morphology...
August 2016: Journal of Cardiovascular Translational Research
https://www.readbyqxmd.com/read/27133525/controversial-and-similar-aspects-of-the-brugada-and-j-wave-patterns-the-vectorcardiogram-point-of-view-revision-2
#4
Carlos Alberto Pastore, Nelson Samesima, Horácio G Pereira Filho, Bruna A Madaloso
BACKGROUND: The J-wave electrocardiographic patterns include early repolarization (ER) and Brugada syndrome; especially when ER is located in the anteroseptal leads (V1-V3), it can mimic the Brugada syndrome (BrS) ECG pattern and therefore mislead the diagnosis. We aimed to define the vectorcardiographic characteristics of BrS and ER using aspects of QRS complex loop, J-point and ST-segment. METHODS/RESULTS: Vectorcardiographic loops in the transverse plane (TP) of 14 BrS patients and 26 individuals with ER were analyzed and defined, and then a third group of 17 patients with non-characteristic ECG patterns were analyzed and compared with them...
May 2016: Journal of Electrocardiology
https://www.readbyqxmd.com/read/26952516/subtraction-electrocardiography-detection-of-ischemia-induced-st-displacement-without-the-need-to-identify-the-j-point
#5
C Cato Ter Haar, Sum-Che Man, Arie C Maan, Martin J Schalij, Cees A Swenne
BACKGROUND: When triaging a patient with acute chest pain at first medical contact, an electrocardiogram (ECG) is routinely made and inspected for signs of myocardial ischemia. The guidelines recommend comparison of the acute and an earlier-made ECG, when available. No concrete recommendations for this comparison exist, neither is known how to handle J-point identification difficulties. Here we present a J-point independent method for such a comparison. METHODS: After conversion to vectorcardiograms, baseline and acute ischemic ECGs after 3minutes of balloon occlusion during elective PCI were compared in 81 patients of the STAFF III ECG database...
May 2016: Journal of Electrocardiology
https://www.readbyqxmd.com/read/26820616/effects-of-preexcitation-syndrome-on-terminal-qrs-vector-observed-in-spatial-vector
#6
Qingru Wang, Yang Chen, Renguang Liu, Qinghua Chang
BACKGROUND: Preexcitation syndrome could affect terminal QRS vector, which is not emphasized in clinic. In this study, we made a comparison between vectorcardiogram (VCG) before and after ablation to observe the change of terminal QRS vector. Furthermore, the relationship between the change of terminal QRS vector and accessory pathway (AP) as well as the change of initial QRS vector (delta vector) was analyzed. METHODS: Thirty patients who were proved to have a single AP by ablation were included...
January 28, 2016: Annals of Noninvasive Electrocardiology
https://www.readbyqxmd.com/read/26806119/frank-vectorcardiographic-system-from-standard-12-lead-ecg-an-effort-to-enhance-cardiovascular-diagnosis
#7
Sidharth Maheshwari, Amit Acharyya, Michele Schiariti, Paolo Emilio Puddu
BACKGROUND: Vectorcardiogram (VCG) has been repeatedly found useful for clinical investigations. It may not substitute but complement Standard 12-Lead (S12) ECG. There was tremendous research between 1950s to mid-1980s on VCG in general and Frank's System in particular, however, in last three decades it has been dropped as a routine cardiac test, the major reasons being unconventional electrode placements which required training of the physicians, greater number of electrodes involved when used to supplement S12 system and additional hardware complexity involved, at least in the early days...
March 2016: Journal of Electrocardiology
https://www.readbyqxmd.com/read/26737464/automatic-cardiac-arrhythmia-detection-and-classification-using-vectorcardiograms-and-complex-networks
#8
Vinícius Queiroz, Eduardo Luz, Gladston Moreira, Álvaro Guarda, David Menotti
This paper intends to bring new insights in the methods for extracting features for cardiac arrhythmia detection and classification systems. We explore the possibility for utilizing vectorcardiograms (VCG) along with electrocardiograms (ECG) to get relevant informations from the heartbeats on the MIT-BIH database. For this purpose, we apply complex networks to extract features from the VCG. We follow the ANSI/AAMI EC57:1998 standard, for classifying the beats into 5 classes (N, V, S, F and Q), and de Chazal's scheme for dataset division into training and test set, with 22 folds validation setup for each set...
2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/26737293/performance-of-dower-s-inverse-transform-and-frank-lead-system-for-identification-of-myocardial-infarction
#9
A Aranda, P Bonizzi, J Karel, R Peeters
This study performs a comparison between Dower's inverse transform and Frank lead system for Myocardial Infarction (MI) identification. We have selected a set of relevant features for MI detection from the vectorcardiogram and used the lasso method after that to build a model for the Dower's inverse transform and one for the Frank leads system. Then we analyzed the performance between both models on MI detection. The proposed methods have been tested using PhysioNet PTB database that contains 550 records from which 368 are MIs...
August 2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/26628581/continuous-rapid-quantification-of-stroke-volume-using-magnetohydrodynamic-voltages-in-3t-magnetic-resonance-imaging
#10
T Stan Gregory, John Oshinski, Ehud J Schmidt, Raymond Y Kwong, William G Stevenson, Zion Tsz Ho Tse
BACKGROUND: To develop a technique to noninvasively estimate stroke volume in real time during magnetic resonance imaging (MRI)-guided procedures, based on induced magnetohydrodynamic voltages (VMHD) that occur in ECG recordings during MRI exams, leaving the MRI scanner free to perform other imaging tasks. Because of the relationship between blood flow (BF) and VMHD, we hypothesized that a method to obtain stroke volume could be derived from extracted VMHD vectors in the vectorcardiogram (VCG) frame of reference (VMHDVCG)...
December 2015: Circulation. Cardiovascular Imaging
https://www.readbyqxmd.com/read/26232766/vectorcardiographic-qrs-area-identifies-delayed-left-ventricular-lateral-wall-activation-determined-by-electroanatomic-mapping-in-candidates-for-cardiac-resynchronization-therapy
#11
Masih Mafi Rad, Gilbert W M Wijntjens, Elien B Engels, Yuri Blaauw, Justin G L M Luermans, Laurent Pison, Harry J Crijns, Frits W Prinzen, Kevin Vernooy
BACKGROUND: Delayed left ventricular (LV) lateral wall (LVLW) activation is considered the electrical substrate underlying LV dysfunction amenable to cardiac resynchronization therapy (CRT). OBJECTIVE: The purpose of this study was to assess LVLW activation in CRT candidates using coronary venous electroanatomic mapping (EAM) and to investigate whether the QRS area (QRSAREA) on the vectorcardiogram (VCG) can identify delayed LVLW activation. METHODS: Fifty-one consecutive CRT candidates (29 left bundle branch block [LBBB], 15 intraventricular conduction delay [IVCD], 7 right bundle branch block [RBBB]) underwent intraprocedural coronary venous EAM using EnSite NavX...
January 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/26027545/vectorcardiographic-diagnostic-prognostic-information-derived-from-the-12-lead-electrocardiogram-historical-review-and-clinical-perspective
#12
REVIEW
Sumche Man, Arie C Maan, Martin J Schalij, Cees A Swenne
In the course of time, electrocardiography has assumed several modalities with varying electrode numbers, electrode positions and lead systems. 12-lead electrocardiography and 3-lead vectorcardiography have become particularly popular. These modalities developed in parallel through the mid-twentieth century. In the same time interval, the physical concepts underlying electrocardiography were defined and worked out. In particular, the vector concept (heart vector, lead vector, volume conductor) appeared to be essential to understanding the manifestations of electrical heart activity, both in the 12-lead electrocardiogram (ECG) and in the 3-lead vectorcardiogram (VCG)...
July 2015: Journal of Electrocardiology
https://www.readbyqxmd.com/read/26025201/an-in-silico-analysis-of-the-effect-of-heart-position-and-orientation-on-the-ecg-morphology-and-vectorcardiogram-parameters-in-patients-with-heart-failure-and-intraventricular-conduction-defects
#13
COMPARATIVE STUDY
Uyên Châu Nguyên, Mark Potse, François Regoli, Maria Luce Caputo, Giulio Conte, Romina Murzilli, Stefano Muzzarelli, Tiziano Moccetti, Enrico G Caiani, Frits W Prinzen, Rolf Krause, Angelo Auricchio
AIM: The aim of this study was to investigate the influence of geometrical factors on the ECG morphology and vectorcardiogram (VCG) parameters. METHODS: Patient-tailored models based on five heart-failure patients with intraventricular conduction defects (IVCDs) were created. The heart was shifted up to 6 cm to the left, right, up, and down and rotated ±30° around the anteroposterior axis. Precordial electrodes were shifted 3 cm down. RESULTS: Geometry modifications strongly altered ECG notching/slurring and intrinsicoid deflection time...
July 2015: Journal of Electrocardiology
https://www.readbyqxmd.com/read/25987408/construction-of-intracardiac-vectorcardiogram-from-implantable-cardioverter-defibrillator-intracardiac-electrograms
#14
Elyar Ghafoori, Muammar M Kabir, Jian Cao, Alexei Shvilkin, Larisa G Tereshchenko
We constructed an intracardiac vectorcardiogram from 3 configurations of intracardiac cardiovertor defibrilator (ICD) electrograms (EGMs). Six distinctive 3 lead combinations were selected out of five leads: can to right ventricular coil (RVC); RVC to superior vena cava coil (SVC); atrial lead tip (A-tip) to right ventricular (RV)-ring; can to RV-ring; RV-tip to RVC, in a patient with dual chamber ICD. Surface spatial QRS-T angle (119.8°) was similar to intracardiac spatial QRS-T angle derived from ICD EGMs combination A (101...
July 2015: Journal of Electrocardiology
https://www.readbyqxmd.com/read/25900820/the-synthesized-vectorcardiogram-resembles-the-measured-vectorcardiogram-in-patients-with-dyssynchronous-heart-failure
#15
COMPARATIVE STUDY
Elien B Engels, Salih Alshehri, Caroline J M van Deursen, Liliane Wecke, Lennart Bergfeldt, Kevin Vernooy, Frits W Prinzen
BACKGROUND: The use of vectorcardiography (VCG) has regained interest, however, original Frank-VCG equipment is rare. This study compares the measured VCGs with those synthesized from the 12-lead electrocardiogram (ECG) in patients with heart failure and conduction abnormalities, who are candidate for cardiac resynchronization therapy (CRT). METHODS: In 92 CRT candidates, Frank-VCG and 12-lead ECG were recorded before CRT implantation. The ECG was converted to a VCG using the Kors method (Kors-VCG) and the two methods were compared using correlation and Bland-Altman analyses...
July 2015: Journal of Electrocardiology
https://www.readbyqxmd.com/read/25743446/vectorcardiography-for-optimization-of-stimulation-intervals-in-cardiac-resynchronization-therapy
#16
MULTICENTER STUDY
Caroline J M van Deursen, Liliane Wecke, Wouter M van Everdingen, Marcus Ståhlberg, Michel H G Janssen, Frieder Braunschweig, Lennart Bergfeldt, Harry J G M Crijns, Kevin Vernooy, Frits W Prinzen
Current optimization of atrioventricular (AV) and interventricular (VV) intervals in cardiac resynchronization therapy (CRT) is time consuming and subject to noise. We aimed to prove the principle that the best hemodynamic effect of CRT is achieved by cancelation of opposing electrical forces, detectable from the QRS morphology in the 3D vectorcardiogram (VCG). Different degrees of left (LV) and right ventricular (RV) pre-excitation were induced, using variation in AV intervals during LV pacing in 20 patients with left bundle branch block (LBBB) and variation in VV intervals during biventricular pacing in 18 patients with complete AV block or atrial fibrillation...
March 2015: Journal of Cardiovascular Translational Research
https://www.readbyqxmd.com/read/25453196/vectorcardiographic-qrs-area-as-a-novel-predictor-of-response-to-cardiac-resynchronization-therapy
#17
Caroline J M van Deursen, Kevin Vernooy, Elton Dudink, Lennart Bergfeldt, Harry J G M Crijns, Frits W Prinzen, Liliane Wecke
BACKGROUND: QRS duration and left bundle branch block (LBBB) morphology are used to select patients for cardiac resynchronization therapy (CRT). We investigated whether the area of the QRS complex (QRSAREA) on the 3-dimensional vectorcardiogram (VCG) can improve patient selection. METHODS: VCG (Frank orthogonal lead system) was recorded prior to CRT device implantation in 81 consecutive patients. VCG parameters, including QRSAREA, were assessed, and compared to QRS duration and morphology...
January 2015: Journal of Electrocardiology
https://www.readbyqxmd.com/read/25230363/t-wave-area-predicts-response-to-cardiac-resynchronization-therapy-in-patients-with-left-bundle-branch-block
#18
COMPARATIVE STUDY
Elien B Engels, Eszter M Végh, Caroline J M Van Deursen, Kevin Vernooy, Jagmeet P Singh, Frits W Prinzen
INTRODUCTION: Chronic heart failure patients with a left ventricular (LV) conduction delay, mostly due to left bundle branch block (LBBB), generally derive benefit from cardiac resynchronization therapy (CRT). However, 30-50% of patients do not show a clear response to CRT. We investigated whether T-wave analysis of the ECG can improve patient selection. METHODS AND RESULTS: The study population comprised 244 CRT recipients with baseline 12-lead electrocardiogram recordings...
February 2015: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/25224074/left-ventricular-mechanical-activation-and-aortic-arch-orientation-recovered-from-magneto-hydrodynamic-voltages-observed-in-12-lead-ecgs-obtained-inside-mris-a-feasibility-study
#19
T Stan Gregory, Ehud J Schmidt, Shelley Hualei Zhang, Raymond Y Kwong, William G Stevenson, Jonathan R Murrow, Zion Tsz Ho Tse
To explore use of the Magnetohydrodynamic Voltage (VMHD), observed in intra-MRI 12-lead electrocardiograms (ECG), to indicate the timing of the onset of left-ventricular mechanical activation (LVMA) and the orientation of the aortic-arch (AAO). Blood flow through the aortic arch during systole, in the presence of the MRI magnetic field (B 0), generates VMHD. Since the magnitude and direction of VMHD are determined by the timing and directionality of blood flow relative to B 0, we hypothesized that clinically useful measures, LVMA and AAO, could be extracted from temporal and vectorial VMHD characteristics...
December 2014: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/25118665/electrocardiogram-derived-respiratory-rate-from-qrs-slopes-and-r-wave-angle
#20
Jesús Lázaro, Alejandro Alcaine, Daniel Romero, Eduardo Gil, Pablo Laguna, Esther Pueyo, Raquel Bailón
A method for estimating respiratory rate from electrocardiogram (ECG) signals is presented. It is based on QRS slopes and R-wave angle, which reflect respiration-induced beat morphology variations. The 12 standard leads, 3 leads from vectorcardiogram (VCG), and 2 additional non-standard leads derived from VCG loops were analyzed. The following series were studied as ECG derived respiration (EDR) signals: slope between the peak of Q and R waves, slope between the peak of R and S waves, and the R-wave angle. Information from several EDR signals was combined in order to increase the robustness of estimation...
October 2014: Annals of Biomedical Engineering
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