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Maren Maanja, Björn Wieslander, Todd T Schlegel, Ljuba Bacharova, Hussein Abu Daya, Yaron Fridman, Timothy C Wong, Erik B Schelbert, Martin Ugander
BACKGROUND: Myocardial fibrosis quantified by myocardial extracellular volume fraction (ECV) and left ventricular mass (LVM) index (LVMI) measured by cardiovascular magnetic resonance might represent independent and opposing contributors to ECG voltage measures of left ventricular hypertrophy (LVH). Diffuse myocardial fibrosis can occur in LVH and interfere with ECG voltage measures. This phenomenon could explain the decreased sensitivity of LVH detectable by ECG, a fundamental diagnostic tool in cardiology...
January 22, 2017: Journal of the American Heart Association
Muammar M Kabir, Erick A Perez-Alday, Jason Thomas, Golriz Sedaghat, Larisa G Tereshchenko
The purpose of this study was to develop optimal configuration of adhesive ECG patches placement on the torso, which would provide the best agreement with the Frank orthogonal ECGs. Ten seconds of orthogonal ECG followed by 3-5min of ECGs using patches at 5 different locations simultaneously on the torso were recorded in 50 participants at rest in sitting position. Median beat was generated for each ECG and 3 patch ECGs that best correlate with orthogonal ECGs were selected for each participant. For agreement analysis, spatial QRS-T angle, spatial QRS and T vector characteristics, spatial ventricular gradient, roundness, thickness and planarity of vectorcardiographic (VCG) loops were measured...
December 29, 2016: Journal of Electrocardiology
Christopher T Villongco, David E Krummen, Jeffrey H Omens, Andrew D McCulloch
AIMS: Left ventricular activation delay due to left bundle branch block (LBBB) is an important determinant of the severity of dyssynchronous heart failure (DHF). We investigated whether patient-specific computational models constructed from non-invasive measurements can provide measures of baseline dyssynchrony and its reduction after CRT that may explain the degree of long-term reverse ventricular remodelling. METHODS AND RESULTS: LV end-systolic volume reduction (ΔESVLV) measured by 2D trans-thoracic echocardiography in eight patients following 6 months of CRT was significantly (P < 0...
December 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Elien B Engels, Thomas T Poels, Patrick Houthuizen, Peter P T de Jaegere, Jos G Maessen, Kevin Vernooy, Frits W Prinzen
AIMS: Left bundle branch block (LBBB) is induced in approximately one-third of all transcatheter aortic valve implantation (TAVI) procedures. We investigated electrophysiological remodelling in patients with TAVI-induced LBBB. METHODS AND RESULTS: This retrospective study comprises 107 patients with initially narrow QRS complex of whom 40 did not and 67 did develop persistent LBBB after TAVI. 12-lead electrocardiograms (ECGs) taken before TAVI, within 24 hours ('acute'), and 1-12 months after TAVI ('chronic') were used to reconstruct vectorcardiograms...
December 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Mirabeau Saha, Giulio Conte, Maria Luce Caputo, François Regoli, Rolf Krause, Angelo Auricchio, Vincent Jacquemet
AIMS: Apparently conflicting clinical measurements of P-wave duration (PWD) pre- vs. post-ablation have been reported. To assist the interpretation of these clinical data, we used a computer model of the atria and torso to simulate P waves before and after pulmonary vein (PV) isolation. METHODS AND RESULTS: Twenty ablation patterns were designed (segmental or ipsilateral ablation; five distances to PV sleeves; addition of a roof line or not). Possible PV reconnections were introduced as gaps in the ablation lines...
December 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
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...
January 2017: Journal of Electrocardiology
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
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
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
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
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...
November 2016: Annals of Noninvasive Electrocardiology
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
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
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
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
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
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
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
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
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
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