keyword
MENU ▼
Read by QxMD icon Read
search

endocardium

keyword
https://www.readbyqxmd.com/read/29119005/differences-in-left-ventricular-functional-adaptation-to-arterial-stiffness-and-neurohormonal-activation-in-patients-with-hypertension-a-study-with-two-dimensional-layer-specific-speckle-tracking-echocardiography
#1
Darae Kim, Chi Young Shim, Geu-Ru Hong, Sungha Park, InJeong Cho, Hyuk-Jae Chang, Jong-Won Ha, Namsik Chung
Background: Arterial stiffness increases pressure load to the left ventricle (LV), leading to LV hypertrophy and subendocardial ischemia. Neurohormones stimulate myocardial fibrosis and LV dysfunction. We aimed to explore the associations of arterial stiffness and plasma aldosterone with multi-directional, layer-specific LV, and left atrial (LA) mechanical function in hypertensive patients. Methods: Layer-specific LV global longitudinal strain (GLS-trans, GLS-endo, GLS-epi), global circumferential strain (GCS-trans, GCS-endo, GCS-epi), LV torsional parameters, and LA global longitudinal strain (LA GLS) were analyzed by two-dimensional speckle tracking echocardiography in 195 hypertensive patients (110 men, mean age 55 years)...
2017: Clinical Hypertension
https://www.readbyqxmd.com/read/29112643/assessment-of-fetal-congenital-heart-diseases-by-4-dimensional-ultrasound-using-spatiotemporal-image-correlation-pictorial-review
#2
Edward Araujo Júnior, Gabriele Tonni, Nathalie Jeanne Bravo-Valenzuela, Fabricio Da Silva Costa, Simon Meagher
The aim of this pictorial review is to describe the technical advances achieved through the application of 4-dimensional (4D) ultrasound using spatiotemporal image correlation (STIC) over conventional 2-dimensional ultrasound in the prenatal detection of congenital heart disease (CHD). Spatiotemporal image correlation is a volume imaging technique that simplifies fetal heart studies while providing more diagnostic information than is typically available from traditional 2-dimensional studies. Four-dimensional software allows the study of cardiac anatomy and function during a single cardiac cycle and has greatly contributed to diagnostic enhancement of CHD...
November 6, 2017: Ultrasound Quarterly
https://www.readbyqxmd.com/read/29107443/recurrent-strokes-after-gore-septal-occluder-device-closure-of-atrial-septal-defect
#3
Adnan Alhadlaq, Arif Hussain, Camille Hancock Friesen, Santokh Dhillon
We report a case of recurrent strokes in a healthy teenager after complete closure of atrial septal defect with Gore Septal Occluder (W.L. Gore and Associates, Newark, DE) device. The disk of the device produced a friction injury to the left atrial endocardium promoting thrombus formation with subsequent embolization to the brain requiring surgical intervention.
September 1, 2017: Canadian Journal of Cardiology
https://www.readbyqxmd.com/read/29084187/-evaluation-of-the-clinical-suitability-of-automated-left-ventricle-s-fraction-and-volume-measurements-in-3-dimensional-echocardiography-compared-to-values-obtained-in-magnetic-resonance-imaging-pilot-study
#4
Agnieszka Żygadło, Magdalena Kaźnica-Wiatr, Justyna Błaut-Jurkowska, Klaudia Knap, Aleksandra Lenart-Migdalska, Monika Smaś-Suska, Maciej Skubera, Małgorzata Urbańczyk-Zawadzka, Piotr Podolec, Maria Olszowska
Recently a lot of authors have been trying to determine the usefulness of 3-dimensional echocardiography (TTE 3D) in evaluation of ejection fraction and left ventricular volume, but few attempt to compare it to the current gold standard of cardiac magnetic resonance (CMR). 3D imaging technics allows to avoid errors caused by geometry of the heart chambers and foreshortened views. American Echocardiographic Guidelines recommend the use of 3-dimensional echocardiography in daily clinical practice. AIM: The aim of the study was to establish clinical usefulness of automated 3D TTE software to calculate left ventricle ejection fraction (LVEF), left ventricle end diastolic volume (LVEDV) and left ventricle end systolic volume (LVESV), and to compare those measurements calculated in CMR and in 3D TTE...
October 23, 2017: Polski Merkuriusz Lekarski: Organ Polskiego Towarzystwa Lekarskiego
https://www.readbyqxmd.com/read/29068072/twenty-four-segment-transverse-ventricular-fractional-shortening-a-new-technique-to-evaluate-fetal-cardiac-function
#5
Greggory R DeVore, Berthold Klas, Gary Satou, Mark Sklansky
OBJECTIVES: Because of various fetal and maternal disease states, this study was conducted to evaluate the fractional shortening of 24 transverse segments distributed from the base to the apex of the ventricular chambers. METHODS: Two hundred control fetuses were examined between 20 and 40 weeks' gestation. The transverse displacement of the ventricular endocardium during the cardiac cycle was computed by using offline software. From the output of the analysis, 24 end-diastolic and end-systolic segments were measured from the base (segment 1) to the apex (segment 24) of the right and left ventricles, and the fractional shortening was computed: [(end-diastolic length - end-systolic length)/end-diastolic length] × 100...
October 25, 2017: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/29060569/intracardiac-electrogram-envelope-detection-during-atrial-fibrillation-using-fast-orthogonal-search
#6
J Hashemi, M H Shariat, D Redfearn
The performance of any intracardiac electrogram processing method is limited by the accuracy of its activation detection approach. The most common activation detection approaches in the literature aim to find the highest peak in the activation envelope disregarding the start and end points. However, the duration of the activation can be used to extract useful information such as wave collisions. In this work, we propose a novel orthogonal based approach for fast and accurate estimation of the start and end of the activations (activation envelope) in intracardiac recordings during atrial fibrillation...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29060108/effects-of-electrophysiological-heterogeneity-on-vulnerability-to-re-entry-in-human-ventricular-tissue-a-simulation-study
#7
Biao Song, Lian Jin, Jianfei Wang, Li Qian, Xiaomei Wu
In this study, we constructed a two-dimensional ventricular tissue sheet with cellular electrophysiology modified from the Ten Tusscher 2006 Model. Heterogeneity was created by dividing the tissue into endocardium, midmyocardium and epicardium, further enhanced by a central ischemic zone. Subsequently, we investigated how electrophysiological heterogeneity affects re-entry initiation and maintenance in this tissue. Furthermore, we analyzed the vulnerable window (VW) under several conditions and concluded that heterogeneity across various myocardia expands the VW further than the monolayer myocardium model does...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29059961/deep-convolutional-neural-networks-for-left-ventricle-segmentation
#8
S Molaei, Me Shiri, K Horan, D Kahrobaei, B Nallamothu, K Najarian
Left ventricle (LV) segmentation is crucial for quantitative cardiac function analysis. Manual segmentation of the endocardium and epicardium is highly cumbersome; physicians limit delineation to the end-diastolic and end-systolic phases. A fully automated system could provide an analysis of cardiac morphology for all phases in a much shorter time. Most of the current LV segmentation methods are semi-automated and require error prone manual initialization. A fully-automated LV segmentation method would expedite the functional analysis of the LV, reduce subjectivity and improve patient experience...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29058109/a-3d-hermite-based-multiscale-local-active-contour-method-with-elliptical-shape-constraints-for-segmentation-of-cardiac-mr-and-ct-volumes
#9
Leiner Barba-J, Boris Escalante-Ramírez, Enrique Vallejo Venegas, Fernando Arámbula Cosío
Analysis of cardiac images is a fundamental task to diagnose heart problems. Left ventricle (LV) is one of the most important heart structures used for cardiac evaluation. In this work, we propose a novel 3D hierarchical multiscale segmentation method based on a local active contour (AC) model and the Hermite transform (HT) for LV analysis in cardiac magnetic resonance (MR) and computed tomography (CT) volumes in short axis view. Features such as directional edges, texture, and intensities are analyzed using the multiscale HT space...
October 23, 2017: Medical & Biological Engineering & Computing
https://www.readbyqxmd.com/read/29050870/brugada-syndrome-is-associated-with-scar-and-endocardial-involvement-insights-from-high-density-mapping-with-the-rhythmia%C3%A2-mapping-system
#10
Rui Providência, Pedro Carmo, Francisco Moscoso Costa, Diogo Cavaco, Francisco Morgado, Mauricio Scanavacca, Pedro Adragão
The authors report the first catheter ablation of Brugada syndrome in the literature using the Rhythmia™ mapping system. Learning points include: (1) low voltage areas can be documented while mapping in some individuals, suggesting that Brugada syndrome may not be a pure ion channel disorder; (2) typical long fractionated potentials can also be identified in the endocardium, supporting the need to map the endocardium in all Brugada patients requiring ablation; (3) disappearance of the typical coved pattern following ablation does not necessarily predict cure, as the patient we present experienced ventricular fibrillation recurrence a few months later...
October 2017: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
https://www.readbyqxmd.com/read/29050828/quantification-of-right-ventricular-size-and-function-from-contrast-enhanced-three-dimensional-echocardiographic-images
#11
Diego Medvedofsky, Victor Mor-Avi, Eric Kruse, Brittney Guile, Boguslawa Ciszek, Lynn Weinert, Megan Yamat, Valentina Volpato, Karima Addetia, Amit R Patel, Roberto M Lang
BACKGROUND: Three-dimensional (3D) echocardiography directly assesses right ventricular (RV) volumes without geometric assumptions, despite the complex shape of the right ventricle, and accordingly is more accurate and reproducible than the two-dimensional methodology, which is able to measure only surrogate parameters of RV function. Volumetric analysis has been hampered by frequent inability to clearly visualize RV endocardium, especially the RV free wall, in 3D echocardiographic images...
October 17, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/29022261/the-non-cardiomyocyte-cells-of-the-heart-their-possible-roles-in-exercise-induced-cardiac-regeneration-and-remodeling
#12
Ivan Varga, Jan Kyselovič, Paulina Galfiova, Lubos Danisovic
The non-cardiomyocyte cellular microenvironment of the heart includes diverse types of cells of mesenchymal origin. During development, the majority of these cells derive from the epicardium, while a subset derives from the endothelium/endocardium and neural crest derived mesenchyme. This subset includes cardiac fibroblasts and telocytes, the latter of which are a controversial type of "connecting cell" that support resident cardiac progenitors in the postnatal heart. Smooth muscle cells, pericytes, and endothelial cells are also present, in addition to adipocytes, which accumulate as epicardial adipose connective tissue...
2017: Advances in Experimental Medicine and Biology
https://www.readbyqxmd.com/read/29021856/refractory-ventricular-tachycardia-caused-by-inflow-cannula-mechanical-injury-in-a-patient-with-left-ventricular-assist-device-catheter-ablation-and-pathological-findings
#13
Stefano Pedretti, Manlio Cipriani, Edgardo Bonacina, Sara Vargiu, Vered Gil Ad, Maria Frigerio, Maurizio Lunati
In patients with left ventricular assist device (LVAD), a minority of post-operative ventricular tachycardias (VTs) is caused by contact between the inflow cannula and the endocardium. Currently, electrophysiologic characteristics and pathologic features of this condition are lacking. We report on a case of a successfully ablated mechanical VT. After VT recurrence, heart transplantation took place. Pathologic observations were consistent with direct tissue injury and inflammation, eventually contributing to persisting arrhythmias...
October 2017: Journal of Arrhythmia
https://www.readbyqxmd.com/read/29021844/intracoronary-acetylcholine-application-as-a-possible-probe-inducing-j-waves-in-patients-with-early-repolarization-syndrome
#14
REVIEW
Toru Maruyama, Kazumasa Fujita, Kei Irie, Shouhei Moriyama, Mitsuhiro Fukata
Acetylcholine is widely used for a diagnostic provocation test of coronary spasm in patients with vasospastic angina. Acetylcholine usually induces coronary vasodilatation mediated by muscarinic receptor activation, but sometimes it evokes vasoconstriction of coronary arteries where the endothelium is damaged. Early repolarization syndrome is characterized by a J wave observed at the end of the QRS complex in a surface electrocardiogram. The J wave is attributed to the transmural voltage gradient at the early repolarization phase across the ventricular wall, which stems mainly from prominent transient outward current in the epicardium, but not in the endocardium...
October 2017: Journal of Arrhythmia
https://www.readbyqxmd.com/read/29020257/reappraising-myocardial-fibrosis-in-severe-aortic-stenosis-an-invasive-and-non-invasive-study-in-133-patients
#15
Thomas A Treibel, Begoña López, Arantxa González, Katia Menacho, Rebecca S Schofield, Susana Ravassa, Marianna Fontana, Steven K White, Carmelo DiSalvo, Neil Roberts, Michael T Ashworth, Javier Díez, James C Moon
Aims: To investigate myocardial fibrosis (MF) in a large series of severe aortic stenosis (AS) patients using invasive biopsy and non-invasive imaging. Methods and results: One hundred thirty-three patients with severe, symptomatic AS accepted for surgical aortic valve replacement underwent cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) and extracellular volume fraction (ECV) quantification. Intra-operative left ventricular (LV) biopsies were performed by needle or scalpel, yielding tissue with (n = 53) and without endocardium (n = 80), and compared with 10 controls...
July 22, 2017: European Heart Journal
https://www.readbyqxmd.com/read/29016778/comparison-between-endocardial-and-epicardial-cardiac-resynchronization-in-an-experimental-model-of-non-ischaemic-cardiomyopathy
#16
Gerard Amorós-Figueras, Esther Jorge, Silvia Raga, Concepcion Alonso-Martin, Enrique Rodríguez-Font, Victor Bazan, Xavier Viñolas, Juan Cinca, Jose M Guerra
Aims: Pacing from the left ventricular (LV) endocardium might increase the likelihood of response to cardiac resynchronization therapy. However, experimental and clinical data supporting this assumption are limited and controversial. The aim of this study was to compare the acute response of biventricular pacing from the LV epicardium and endocardium in a swine non-ischaemic cardiomyopathy (NICM) model of dyssynchrony. Methods and results: A NICM was induced in six swine by 3 weeks of rapid ventricular pacing...
July 17, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28992169/points-to-consider-when-doing-a-trial-primarily-involving-the-heart
#17
REVIEW
Yannick Allanore, Oliver Distler, Ulrich A Walker, Dinesh Khanna, Daniel E Furst, Christophe Meune
Cardiac involvement contributes to the severity of SSc and should carefully be investigated and managed in SSc patients. Although it is commonly sub-clinical, once symptomatic it has a poor prognosis. Several complementary tools (circulating biomarkers, electrocardiography, echocardiography, scintigraphy or MRI) allow the assessment of all the various cardiac structures (endocardium, myocardium and pericardium) and heart function. Treatment remains empirical but cardiac trials in SSc can add data to the treatment of this complication...
September 1, 2017: Rheumatology
https://www.readbyqxmd.com/read/28985343/angiotensinergic-innervation-of-the-human-right-atrium-implications-for-cardiac-reflexes
#18
Jürgen Bohlender, Jürg Nussberger, Hendrik Tevaearai, Hans Imboden
Background: The right atrium is densely innervated and provides sensory input to important cardio-circulatory reflexes controlling cardiac output and blood pressure. Its angiotensin (Ang) II-expressing innervation may release Ang II as a neuropeptide co-transmitter to modulate reflexes but has not yet been characterized. Methods: Intraoperative surgical biopsies from human right atria (n=7) were immunocytologically stained for Ang II, tyrosine hydroxylase (TH) and synaptophysin (SYN)...
September 5, 2017: American Journal of Hypertension
https://www.readbyqxmd.com/read/28964115/highly-trabeculated-structure-of-the-human-endocardium-underlies-asymmetrical-response-to-low-energy-monophasic-shocks
#19
Adam Connolly, Matthew D Robson, Jürgen Schneider, Rebecca Burton, Gernot Plank, Martin J Bishop
Novel low-energy defibrillation therapies are thought to be driven by virtual-electrodes (VEs), due to the interaction of applied monophasic electric shocks with fine-scale anatomical structures within the heart. Significant inter-species differences in the cardiac (micro)-anatomy exist, however, particularly with respect to the degree of endocardial trabeculations, which may underlie important differences in response to low-energy defibrillation protocols. Understanding the interaction of monophasic electric fields with the specific human micro-anatomy is therefore imperative in facilitating the translation and optimisation of these promising experimental therapies to the clinic...
September 2017: Chaos
https://www.readbyqxmd.com/read/28952932/localization-of-origins-of-premature-ventricular-contraction-by-means-of-convolutional-neural-network-from-12-lead-ecg
#20
Ting Yang, Long Yu, Qi Jin, Liqun Wu, Bin He
OBJECTIVE: This paper proposes a novel method to localize origins of premature ventricular contractions (PVCs) from 12-lead electrocardiography (ECG) using convolutional neural network (CNN) and a realistic computer heart model. METHODS: The proposed method consists of two CNNs (Segment CNN and Epi-Endo CNN) to classify among ventricular sources from 25 segments and from epicardium (Epi) or endocardium (Endo). The inputs are the full time courses and the first half of QRS complexes of 12-lead ECG, respectively...
September 25, 2017: IEEE Transactions on Bio-medical Engineering
keyword
keyword
101845
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"