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https://www.readbyqxmd.com/read/29226899/successful-resection-and-reconstruction-of-primary-cardiac-lymphoma
#1
Barçın Özcem, Hatice Soner Kemal, Özlem Balcıoğlu, Hanife Özkayalar, İlhan Sanisoğlu
Primary cardiac lymphoma (PCL) is one of the rarest tumors of the heart. The most common type is diffuse, large B-cell lymphoma. Most often, the right atrium and the right ventricle are involved, and if not diagnosed and treated in time, it can be fatal. In this case, a female patient underwent an urgent operation for a large, infiltrative, right atrial mass. Extensive resection of the lateral walls of both atria and the interatrial septum as well as reconstruction were performed successfully. The pathological evaluation suggested PCL...
December 2017: Türk Kardiyoloji Derneği Arşivi: Türk Kardiyoloji Derneğinin Yayın Organıdır
https://www.readbyqxmd.com/read/29223114/regional-conduction-velocity-calculation-from-clinical-multichannel-electrograms-in-human-atria
#2
Bhawna Verma, Tobias Oesterlein, Axel Loewe, Armin Luik, Claus Schmitt, Olaf Dössel
BACKGROUND: During atrial fibrillation, heterogeneities and anisotropies result in a chaotic propagation of the depolarization wavefront. The electrophysiological parameter called conduction velocity (CV) influences the propagation pattern over the atrium. We present a method that determines the regional CV for deformed catheter shapes, which result due to the catheter movement and changing wall contact. METHODS: The algorithm selects stable catheter positions, finds the local activation times (LAT), considers the wall contact and calculates all CV estimates within the area covered by the catheter...
November 26, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/29218529/quantification-of-cell-surface-glucose-transporters-in-the-heart-using-a-biotinylated-photolabeling-assay
#3
Zahra Maria, Véronique A Lacombe
The biotinylated photolabeling assay enables quantification of cell-surface glucose transporters (GLUTs). This technique has been successfully applied to quantify the cell-surface GLUT protein content in striated muscles and adipose tissue, as a means to evaluate GLUT trafficking. Here, we describe the detailed method of quantifying the cell-surface content of several GLUT isoforms (1, 4, 8, and 12) in isolated cardiac myocytes, as well as in the intact perfused atria and ventricle.
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29218016/synergistic-anti-arrhythmic-effects-in-human-atria-with-combined-use-of-sodium-blockers-and-acacetin
#4
Haibo Ni, Dominic G Whittaker, Wei Wang, Wayne R Giles, Sanjiv M Narayan, Henggui Zhang
Atrial fibrillation (AF) is the most common cardiac arrhythmia. Developing effective and safe anti-AF drugs remains an unmet challenge. Simultaneous block of both atrial-specific ultra-rapid delayed rectifier potassium (K+) current (IKur) and the Na+ current (INa) has been hypothesized to be anti-AF, without inducing significant QT prolongation and ventricular side effects. However, the antiarrhythmic advantage of simultaneously blocking these two channels vs. individual block in the setting of AF-induced electrical remodeling remains to be documented...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29217489/fixed-volume-particle-trace-emission-for-the-analysis-of-left-atrial-blood-flow-using-4d-flow-mri
#5
Stephen Gaeta, Petter Dyverfeldt, Jonatan Eriksson, Carl-Johan Carlhäll, Tino Ebbers, Ann F Bolger
4D Flow MRI has been used to quantify normal and deranged left ventricular blood flow characteristics on the basis of functionally distinct flow components. However, the application of this technique to the atria is challenging due to the presence of continuous inflow. This continuous inflow necessitates plane-based emission of particle traces from the inlet veins, leading to particles that represents different amounts of blood, and related quantification errors. The purpose of this study was to develop a novel fixed-volume approach for particle tracing and employ this method to develop quantitative analysis of 4D blood flow characteristics in the left atrium...
December 4, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29216985/eplerenone-reduces-atrial-fibrillation-burden-without-preventing-atrial%C3%A2-electrical-remodeling
#6
Yoshio Takemoto, Rafael J Ramirez, Kuljeet Kaur, Oscar Salvador-Montañés, Daniela Ponce-Balbuena, Roberto Ramos-Mondragón, Steven R Ennis, Guadalupe Guerrero-Serna, Omer Berenfeld, José Jalife
BACKGROUND: The aldosterone inhibitor eplerenone (EPL) has been shown to reduce the incidence of atrial fibrillation (AF) in patients with systolic heart failure, but the mechanism is unknown. OBJECTIVES: This study hypothesized that by reducing atrial dilation and fibrosis in the absence of heart failure, EPL also reduces AF burden and prevents AF perpetuation. METHODS: The authors conducted a randomized controlled study in 34 sheep that were atrially tachypaced (13 ± 1 week)...
December 12, 2017: Journal of the American College of Cardiology
https://www.readbyqxmd.com/read/29212469/orthogonal-p-wave-morphology-is-affected-by-intra-atrial-pressures
#7
Richard Petersson, J Gustav Smith, David A Larsson, Öyvind Reitan, Jonas Carlson, Pyotr Platonov, Fredrik Holmqvist
BACKGROUND: It has previously been shown that the morphology of the P-wave neither depends on atrial size in healthy subjects with physiologically enlarged atria nor on the physiological anatomical variation in transverse orientation of the left atrium. The present study aimed to investigate if different pressures in the left and right atrium are associated with different P-wave morphologies. METHODS: 38 patients with isolated, increased left atrial pressure, 51 patients with isolated, increased right atrial pressure and 76 patients with biatrially increased pressure were studied...
December 6, 2017: BMC Cardiovascular Disorders
https://www.readbyqxmd.com/read/29202929/live-imaging-of-heart-tube-development-in-mouse-reveals-alternating-phases-of-cardiac-differentiation-and-morphogenesis
#8
Kenzo Ivanovitch, Susana Temiño Valbuena, Miguel Torres
During vertebrate heart development two progenitor populations, first and second heart fields (FHF, SHF), sequentially contribute to longitudinal subdivisions of the heart tube (HT), with the FHF contributing the left ventricle and part of the atria, and the SHF the rest of the heart. Here we study the dynamics of cardiac differentiation and morphogenesis by tracking individual cells in live analysis of mouse embryos. We report that during an initial phase, FHF precursors differentiate rapidly to form a cardiac crescent, while limited morphogenesis takes place...
December 5, 2017: ELife
https://www.readbyqxmd.com/read/29202441/income-egalitarianism-and-attitudes-towards-healthcare-policy-a-study-on-public-attitudes-in%C3%A2-29%C3%A2-countries
#9
A Azar, L Maldonado, J C Castillo, J Atria
OBJECTIVES: To evaluate the relationship between income and egalitarian values and attitudes towards healthcare policy. STUDY DESIGN: Cross-sectional and cross-national study. METHODS: Data for 29 countries from the International Social Survey Programme (ISSP) 2011 were used. The dependent variables are a general attitude towards government involvement in healthcare provision and two attitudes regarding specific policies (taxes and public funding)...
December 1, 2017: Public Health
https://www.readbyqxmd.com/read/29200910/comparative-effects-of-angiotensin-ii-and-angiotensin-4-8-on-blood-pressure-and-anp-secretion-in-rats
#10
Hoang Thi Ai Phuong, Lamei Yu, Byung Mun Park, Suhn Hee Kim
Angiotensin II (Ang II) is metabolized from N-terminal by aminopeptidases and from C-terminal by Ang converting enzyme (ACE) to generate several truncated angiotensin peptides (Angs). The truncated Angs have different biological effects but it remains unknown whether Ang-(4-8) is an active peptide. The present study was to investigate the effects of Ang-(4-8) on hemodynamics and atrial natriuretic peptide (ANP) secretion using isolated beating rat atria. Atrial stretch caused increases in atrial contractility by 60% and in ANP secretion by 70%...
November 2017: Korean Journal of Physiology & Pharmacology
https://www.readbyqxmd.com/read/29193078/termination-of-reentrant-atrial-tachycardia-via-optogenetic-stimulation-with-optimized-spatial-targeting-insights-from-computational-models
#11
Patrick M Boyle, Michael J Murphy, Thomas V Karathanos, Sohail Zahid, Robert C Blake, Natalia A Trayanova
Optogenetics has emerged as a potential alternative to electrotherapy for treating arrhythmia, but feasibility studies have been limited to ventricular defibrillation via epicardial light application. Here, we assess the efficacy of optogenetic atrial tachycardia (AT) termination in human hearts using a strategy that targets for illumination specific regions identified in an automated manner. In three patient-specific models reconstructed from late gadolinium-enhanced MRI scans, we simulated channelrhodopsin-2 (ChR2) expression via gene delivery...
November 28, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/29186007/anatomically-realistic-ultrasound-phantoms-using-gel-wax-with-3d-printed-moulds
#12
Efthymios Maneas, Wenfeng Xia, Daniil I Nikitichev, Batol Daher, Maniragav Manimaran, Rui Yen J Wong, Chia-Wei Chang, Benyamin Rahmani, Claudio Capelli, Silvia Schievano, Gaetano Burriesci, Sebastien Ourselin, Anna L David, Malcolm Finlay, Simeon J West, Tom Vercauteren, Adrien E Desjardins
Here we describe methods for creating tissue-mimicking ultrasound phantoms based on patient anatomy using a soft material called gel wax. To recreate acoustically realistic tissue properties, two additives to gel wax were considered: paraffin wax to increase acoustic attenuation, and solid glass spheres to increase backscattering. The frequency dependence of ultrasound attenuation was well described with a power law over the measured range of 3 to 10 MHz. With the addition of paraffin wax in concentrations of 0 to 8 w/w%, attenuation varied from 0...
November 29, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29178881/atrial-erk1-2-activation-in-the-embryo-leads-to-incomplete-septal-closure-a-novel-mouse-model-of-atrial-septal-defect
#13
Che-Chung Yeh, Yanying Fan, Yi-Lin Yang, Michael J Mann
BACKGROUND: MEK1 mutation and activated MAPK signaling has been found in patients with RASopathies and abnormal cardiac development. Previous studies have suggested that regulation of fetal MAPK signaling is essential for normal cardiac development. We investigated the effect of active MEK1 overexpression on fetal atrial septal development. METHODS AND RESULTS: An inducible double transgenic (DTg) mouse model was developed in which cardiac-specific fetal expression of a constitutively active form of human MEK1 (aMEK1) was induced primarily in the atrium via the withdrawal of doxycycline from the drinking water of pregnant mice...
November 24, 2017: Journal of Biomedical Science
https://www.readbyqxmd.com/read/29174249/low-interatrial-septal-pacing-a-simple-method
#14
Asit Das, Dhiman Kahali, Shibananda Dutta
BACKGROUND: Sinus node disease is associated with widespread structural and electrophysiological changes in the atria in addition to abnormalities at the sinus node. The atrial conduction disorder in patients with atrial pacing results in higher incidence of atrial fibrillation. Studies have shown that low interatrial septal pacing is superior to right atrial appendage pacing in preventing persistent or permanent atrial fibrillation in these patients. However, implantation of active fixation lead in low interatrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this method in routine practice...
November 2017: Indian Heart Journal
https://www.readbyqxmd.com/read/29173610/endothelial-nitric-oxide-synthase-induced-hypertrophy-and-vascular-dysfunction-contribute-to-the-left-ventricular-dysfunction-in-caveolin-1-mice
#15
Annette Ebner, Nadine Kuerbis, Aljoscha Brandt, Birgit Zatschler, Sönke Weinert, David M Poitz, Bernd Ebner, Antje Augstein, Carsten Wunderlich, Ali El-Armouche, Ruth H Strasser
BACKGROUND: Caveolin-1 (Cav1)-/- mice display impaired development of left ventricular pressure and increased left ventricular wall thickness but no dilated ventricle; these are typical findings in patients with heart failure with preserved ejection fraction (HfpEF). Aiming to clarify if dysfunctional endothelial nitric oxide synthase (eNOS) influences cardiomyocyte contractility, cardiac conduction system, or afterload/vascular resistance, we studied Cav1-/-/eNOS-/- mice. METHODS: Cardiac function was assessed in vivo by pressure-volume-catheterization of the left ventricle, echocardiography and electrocardiography...
December 2017: Canadian Journal of Cardiology
https://www.readbyqxmd.com/read/29166721/-a-preliminary-study-on-the-relationship-between-idiopathic-arrhythmia-and-cardiac-magnetic-resonance-imaging-defined-cardiac-features-in-patients-with-straight-back-syndrome
#16
L Chen, X H Ma, L Zhao, R Bai, S N Li, L Wang, H Chen, Z M Fan, M W Lou, Y D Niu
Objective: To retrospectively analyze the potential correlation between cardiac magnetic resonance (CMR) imaging and clinical features and idiopathic arrhythmia in patients with straight back syndrome (SBS). Methods: Patients receiving CMR imaging examination from April 2015 to March 2016 at our department (n=1 432) were screened, 76 patients met the diagnosis criteria of flat chest (anteroposterior diameter/transthoracic diameter (APD/TTD) ratio<0.37 at the T8 vertebra). After excluding 33 patients with structural heart disease, 43 SBS patients were divided into two groups: SBS without obvious morphological change in the heart (group A, n=19) and SBS with morphological change of the heart (group B, n=24)...
November 24, 2017: Zhonghua Xin Xue Guan Bing za Zhi
https://www.readbyqxmd.com/read/29166718/-value-of-two-left-atrium-and-pulmonary-vein-stereoscopic-imaging-reconstruction-methods-on-guiding-radiofrequency-ablation-for-atrial-fibrillation
#17
Y Tian, S Zhou, Y H Yin, Y X Zheng, R P Wang, X Q Liu, Z Q Liu, Q F Liu, W Liu, J Pang, Z Jiang, L H Tian, J Huang, L Yang
Objective: To compare the value of two 3D imaging reconstruction methods for left atria and pulmonary vein on guiding the catheter ablation for atrial fibrillation (AF). Methods: From January 2014 to January 2017, a total of 100 drug refractory paroxysmal AF patients were divided into left atria direct angiography group (n=50), and indirect angiography group (n=50). 3D CARTO system was applied for mapping and guiding the ablation procedure. Patients assigned to direct angiography group were treated as follows: intraoperative puncture of atrial septum, inject contrast agent directly into the left atrium, conduct left atrial and pulmonary venous rotation angiography, reconstruct three-dimensional image, integrate the image into real-time X-ray system to facilitate circumferential pulmonary vein isolation...
November 24, 2017: Zhonghua Xin Xue Guan Bing za Zhi
https://www.readbyqxmd.com/read/29163179/in-silico-assessment-of-efficacy-and-safety-of-ikur-inhibitors-in-chronic-atrial-fibrillation-role-of-kinetics-and-state-dependence-of-drug-binding
#18
Nicholas Ellinwood, Dobromir Dobrev, Stefano Morotti, Eleonora Grandi
Current pharmacological therapy against atrial fibrillation (AF), the most common cardiac arrhythmia, is limited by moderate efficacy and adverse side effects including ventricular proarrhythmia and organ toxicity. One way to circumvent the former is to target ion channels that are predominantly expressed in atria vs. ventricles, such as KV1.5, carrying the ultra-rapid delayed-rectifier K(+) current (IKur). Recently, we used an in silico strategy to define optimal KV1.5-targeting drug characteristics, including kinetics and state-dependent binding, that maximize AF-selectivity in human atrial cardiomyocytes in normal sinus rhythm (nSR)...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/29159313/fibrosis-and-atrial-fibrillation-computerized-and-optical-mapping-a-view-into-the-human-atria-at-submillimeter-resolution
#19
Brian J Hansen, Jichao Zhao, Vadim V Fedorov
Recent studies strongly suggest that the majority of atrial fibrillation (AF) patients with diagnosed or subclinical cardiac diseases have established or even pre-existing fibrotic structural remodeling, which may lead to conduction abnormalities and reentrant activity that sustain AF. As conventional treatments fail to treat AF in far too many cases, an urgent need exists to identify specific structural arrhythmogenic fibrosis patterns, which may maintain AF, in order to identify effective ablation targets for AF treatment...
June 2017: JACC. Clinical Electrophysiology
https://www.readbyqxmd.com/read/29157563/nr2f1a-balances-atrial-chamber-and-atrioventricular-canal-size-via-bmp-signaling-independent-and-dependent-mechanisms
#20
Tiffany B Duong, Padmapriyadarshini Ravisankar, Yuntao Charlie Song, Jacob T Gafranek, Ariel B Rydeen, Tracy E Dohn, Lindsey A Barske, J Gage Crump, Joshua S Waxman
Determination of appropriate chamber size is critical for normal vertebrate heart development. Although Nr2f transcription factors promote atrial maintenance and differentiation, how they determine atrial size remains unclear. Here, we demonstrate that zebrafish Nr2f1a is expressed in differentiating atrial cardiomyocytes. Zebrafish nr2f1a mutants have smaller atria due to a specific reduction in atrial cardiomyocyte (AC) number, suggesting it has similar requirements to Nr2f2 in mammals. Furthermore, the smaller atria in nr2f1a mutants are derived from distinct mechanisms that perturb AC differentiation at the chamber poles...
November 17, 2017: Developmental Biology
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