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https://www.readbyqxmd.com/read/28722247/left-ventricular-function-and-regional-strain-with-subtly-tagged-steady-state-free-precession-feature-tracking
#1
Eric M Schrauben, Brett R Cowan, Andreas Greiser, Alistair A Young
PURPOSE: To provide regional strain and ventricular volume from a single acquisition, using subtly tagged steady-state free precession (SubTag SSFP) feature tracking. MATERIALS AND METHODS: The effects on regional strain of tag strength in gradient recalled echo (GRE) tagging, flip angle in untagged balanced SSFP, and both in SubTag SSFP were examined in the mid left ventricle of 15 healthy volunteers at 3T. Optimal parameters were determined from varying both tag strength and SSFP flip angle using full tag saturation GRE as the reference standard...
July 19, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28716687/measures-of-ventricular-arterial-coupling-and-incident-heart-failure-preserved-ejection-fraction-hfpef-a-matched-case-control-analysis
#2
Carolyn L Lekavich, Debra J Barksdale, Jia-Rong Wu, Virginia Neelon, Jamie Crandell, Eric J Velazquez
OBJECTIVES: This study was designed to detect differences in markers associated with incident heart failure preserved ejection fraction (HFpEF) when comparing matched case-control groups. BACKGROUND: Evidence continues to demonstrate increasing prevalence, cost and mortality implications of HFpEF, but clearly defined parameters that distinguish between controls and HFpEF have not been established. METHODS: A study cohort of case (incident patients with HFpEF, n=155) and matched control (patients with no prior HF, n=155) groups was retrospectively identified...
July 14, 2017: Journal of Cardiac Failure
https://www.readbyqxmd.com/read/28678927/global-longitudinal-strain-or-left-ventricular-twist-and-torsion-which-correlates-best-with-ejection-fraction
#3
Marcio Silva Miguel Lima, Hector R Villarraga, Maria Cristina Donadio Abduch, Marta Fernandes Lima, Cecilia Beatriz Bittencourt Viana Cruz, João Cesar Nunes Sbano, Mariana Callil Voos, Wilson Mathias, Jeane Mike Tsutsui
Background: Estimative of left ventricular ejection fraction (LVEF) is a major indication for echocardiography. Speckle tracking echocardiography (STE) allows analysis of LV contraction mechanics which includes global longitudinal strain (GLS) and twist/torsion, both the most widely used. Direct comparison of correlations between these novel parameters and LVEF has never been done before. Objective: This study aims to check which one has the highest correlation with LVEF...
June 29, 2017: Arquivos Brasileiros de Cardiologia
https://www.readbyqxmd.com/read/28669395/afterload-dependence-of-right-ventricular-myocardial-strain
#4
Leah Wright, Kazuaki Negishi, Nathan Dwyer, Sudhir Wahi, Thomas H Marwick
BACKGROUND: Right ventricular (RV) free wall strain (RVFWS) is a feasible method for quantitation and follow-up of RV function and may have benefits over traditional markers such as fractional area change. However, like all ejection phase parameters, RVFWS is difficult to assess in the presence of changing afterload. The aim of this study was to compare RVFWS and traditional RV function parameters for tracking progress of RV function in patients with pulmonary arterial hypertension (PAH) over a range of pulmonary artery systolic pressure (PASPs)...
July 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/28664568/circulating-microrna-in-patients-with-repaired-tetralogy-of-fallot
#5
Clare Tm Lai, Enders Ko Ng, Pak-Cheong Chow, Ava Kwong, Yiu-Fai Cheung
BACKGROUND: Emerging data suggest that heart-related microRNAs (miRs) may serve as circulating biomarkers of myocardial injury. We aimed to determine the circulating profile of miRs in patients with volume-overloaded right ventricles after repair of tetralogy (TOF). METHODS: A total of 104 TOF patients and 70 controls were recruited. The study was conducted into two phases: I) determination of circulating heart-related miRs described in left heart diseases (miR-1, miR-133a, miR208a, miR-208b and miR423-5p) by quantitative real time-PCR in 49 patients and 30 controls and followed by validation in an independent cohort of 55 patients and 40 controls; II) expression profiling of serum samples from 8 patients and 8 controls, followed by validation...
June 29, 2017: European Journal of Clinical Investigation
https://www.readbyqxmd.com/read/28664480/usefulness-of-left-ventricular-speckle-tracking-echocardiography-and-novel-measures-of-left-atrial-structure-and-function-in-diagnosing-paroxysmal-atrial-fibrillation-in-ischemic-stroke-and-transient-ischemic-attack-patients
#6
Kristoffer Grundtvig Skaarup, Hanne Christensen, Nis Høst, Masti Mahdy Mahmoud, Christian Ovesen, Flemming Javier Olsen, Jan Skov Jensen, Tor Biering-Sørensen
Asymptomatic paroxysmal atrial fibrillation (PAF) is often assumed to be the cause of cryptogenic ischemic strokes (IS) and transient ischemic attacks (TIA). We examined the usefulness of measures obtained by 2D speckle tracking echocardiography and novel left atrial measurements, in the diagnosis of PAF in patients with IS and TIA. We retrospectively included 205 patients who after acute IS or TIA underwent an echocardiogram in sinus rhythm. Patients were designated as PAF-patients if they had one or more reported incidents of AF before or after their echocardiographic examination...
June 29, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/28655468/revisiting-the-cram%C3%A3-r-rao-lower-bound-for-elastography-predicting-the-performance-of-axial-lateral-and-polar-strain-elastograms
#7
Prashant Verma, Marvin M Doyley
We derived the Cramér Rao lower bound for 2-D estimators employed in quasi-static elastography. To illustrate the theory, we modeled the 2-D point spread function as a sinc-modulated sine pulse in the axial direction and as a sinc function in the lateral direction. We compared theoretical predictions of the variance incurred in displacements and strains when quasi-static elastography was performed under varying conditions (different scanning methods, different configuration of conventional linear array imaging and different-size kernels) with those measured from simulated or experimentally acquired data...
June 24, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28648418/longitudinal-ventricular-systolic-dysfunction-in-patients-with-very-severe-obstructive-sleep-apnea-a-case-control-study-using-speckle-tracking-imaging
#8
Mithun Jacob Varghese, Gautam Sharma, Garima Shukla, Sandeep Seth, Sundeep Mishra, Anupama Gupta, Vinay Kumar Bahl
OBJECTIVE: Obstructive sleep apnea (OSA) is a prevalent condition that is increasingly recognized to be associated with cardiovascular disease. We aimed to investigate the subclinical systolic ventricular dysfunction of patients with OSA using novel speckle tracking echocardiographic (STE) techniques. METHODS: This study included 31 patients of polysomnography proven very severe OSA [Apnea Hypopnea Index(AHI) >40] and an equal number of matched population with no OSA as controls...
May 2017: Indian Heart Journal
https://www.readbyqxmd.com/read/28647901/in-vivo-visualization-of-the-locus-coeruleus-in-humans-quantifying-the-test-retest-reliability
#9
Klodiana-Daphne Tona, Max C Keuken, Mischa de Rover, Egbert Lakke, Birte U Forstmann, Sander Nieuwenhuis, Matthias J P van Osch
The locus coeruleus (LC) is a brainstem nucleus involved in important cognitive functions. Recent developments in neuroimaging methods and scanning protocols have made it possible to visualize the human LC in vivo by utilizing a T1-weighted turbo spin echo (TSE) scan. Despite its frequent use and its application as a biomarker for tracking the progress of monoaminergic-related neurodegenerative diseases, no study to date has investigated the reproducibility and inter-observer variability of LC identification using this TSE scan sequence...
June 24, 2017: Brain Structure & Function
https://www.readbyqxmd.com/read/28647400/intraoperative-registered-ultrasound-and-fluoroscopy-iruf-for-dose-calculation-during-prostate-brachytherapy-improved-accuracy-compared-to-standard-ultrasound-based-dosimetry
#10
Junghoon Lee, Omar Y Mian, Yi Le, Hee Joon Bae, E Clif Burdette, Theodore L DeWeese, Jerry L Prince, Daniel Y Song
BACKGROUND AND PURPOSE: Intraoperative transrectal ultrasound dosimetry during low-dose-rate prostate brachytherapy is imprecise due to sonographic distortion caused by seed echoes and needle tracks that obscure seed positions or create false signals as well as traumatic edema. Here we report the results of a pilot study comparing a combined ultrasound and fluoroscopy-based seed localization method (iRUF) to standard ultrasound-based dosimetry (USD). MATERIAL AND METHODS: Eighty patients undergoing permanent Pd-103 seed implantation for prostate cancer were prospectively enrolled...
June 21, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28643530/assessment-of-local-carotid-stiffness-in-seronegative-and-seropositive-rheumatoid-arthritis
#11
Abdullah Nabi Aslan, Ayşe Nur Şirin Özcan, Şükran Erten, Yakup Alsancak, Tahir Durmaz
OBJECTIVES: Rheumatoid arthritis (RA) is a chronic, inflammatory disease associated with increased risk of cardiovascular (CV) disease. Arterial stiffness (AS) is an independent predictor of CV events. This study aimed to analyse local carotid AS parameters in seronegative and seropositive RA patients. DESIGN: Of 347 consecutive RA patients, we selected specifically those who were free of established CV diseases and risk factors. As a result, 140 patients (126 women, 52...
June 23, 2017: Scandinavian Cardiovascular Journal: SCJ
https://www.readbyqxmd.com/read/28643408/the-effect-of-concomitant-fields-in-fast-spin-echo-acquisition-on-asymmetric-mri-gradient-systems
#12
Shengzhen Tao, Paul T Weavers, Joshua D Trzasko, John Huston, Yunhong Shu, Erin M Gray, Thomas K F Foo, Matt A Bernstein
PURPOSE: To investigate the effect of the asymmetric gradient concomitant fields (CF) with zeroth and first-order spatial dependence on fast/turbo spin-echo acquisitions, and to demonstrate the effectiveness of their real-time compensation. METHODS: After briefly reviewing the CF produced by asymmetric gradients, the effects of the additional zeroth and first-order CFs on these systems are investigated using extended-phase graph simulations. Phantom and in vivo experiments are performed to corroborate the simulation...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28623549/elevated-circulating-pcsk9-concentrations-predict-subclinical-atherosclerotic-changes-in-low-risk-obese-and-non-obese-patients
#13
Štefan Tóth, Ján Fedačko, Tímea Pekárová, Zdenka Hertelyová, Matan Katz, Adil Mughees, Jozef Kuzma, Peter Štefanič, Ivan Kopolovets, Daniel Pella
INTRODUCTION: Many studies have highlighted the important role of PCSK9 in the development of cardiometabolic changes and its possible function as a biomarker of myocardial infarction or ischemic heart disease. This study aimed to determine the relationship between circulating PCSK9 levels and subclinical vascular changes in the group of low risk patients without manifest cardiovascular diseases. METHODS: In this study, 120 healthy patients, free of manifest cardiovascular diseases, diabetes mellitus, and without lipid-lowering therapy, were divided into three groups based on BMI: normal weight (N = 50), overweight (N = 30), and obese (N = 40)...
June 16, 2017: Cardiology and Therapy
https://www.readbyqxmd.com/read/28616842/characterization-of-magneto-endosymbionts-as-mri-cell-labeling-and-tracking-agents
#14
Kimberly D Brewer, Ryan Spitler, Kayla R Lee, Andrea C Chan, Joyce C Barrozo, Abdul Wakeel, Chandler S Foote, Steven Machtaler, James Rioux, Juergen K Willmann, Papia Chakraborty, Bradley W Rice, Christopher H Contag, Caleb B Bell, Brian K Rutt
PURPOSE: Magneto-endosymbionts (MEs) show promise as living magnetic resonance imaging (MRI) contrast agents for in vivo cell tracking. Here we characterize the biomedical imaging properties of ME contrast agents, in vitro and in vivo. PROCEDURES: By adapting and engineering magnetotactic bacteria to the intracellular niche, we are creating magneto-endosymbionts (MEs) that offer advantages relative to passive iron-based contrast agents (superparamagnetic iron oxides, SPIOs) for cell tracking...
June 14, 2017: Molecular Imaging and Biology: MIB: the Official Publication of the Academy of Molecular Imaging
https://www.readbyqxmd.com/read/28603000/validation-of-a-defibrillation-lead-ventricular-volume-measurement-compared-to-three-dimensional-echocardiography
#15
David E Haines, Wilson Wong, Robert Canby, Coty Jewell, Mahmoud Houmsse, David Pederson, Lissa Sugeng, John Porterfield, Anil Kottam, John Pearce, Jon Valvano, Joel Michalek, Aron Trevino, Sandeep Sagar, Marc D Feldman
BACKGROUND: There is increasing evidence that using frequent invasive measures of pressure in patients with heart failure results in improved outcomes compared to traditional measures. Admittance, a measure of volume derived from preexisting defibrillation leads, is proposed as a new technique to monitor cardiac hemodynamics in patients with an implantable defibrillator. OBJECTIVE: The purpose of this study was to evaluate the accuracy of a new ventricular volume sensor (VVS, CardioVol) compared with 3-dimenssional echocardiography (echo) in patients with an implantable defibrillator...
June 9, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28589126/myocardial-architecture-mechanics-and-fibrosis-in-congenital-heart-disease
#16
REVIEW
Sarah Ghonim, Inga Voges, Peter D Gatehouse, Jennifer Keegan, Michael A Gatzoulis, Philip J Kilner, Sonya V Babu-Narayan
Congenital heart disease (CHD) is the most common category of birth defect, affecting 1% of the population and requiring cardiovascular surgery in the first months of life in many patients. Due to advances in congenital cardiovascular surgery and patient management, most children with CHD now survive into adulthood. However, residual and postoperative defects are common resulting in abnormal hemodynamics, which may interact further with scar formation related to surgical procedures. Cardiovascular magnetic resonance (CMR) has become an important diagnostic imaging modality in the long-term management of CHD patients...
2017: Frontiers in Cardiovascular Medicine
https://www.readbyqxmd.com/read/28585511/three-dimensional-ultrasound-elasticity-imaging-on-an-automated-breast-volume-scanning-system
#17
Yuqi Wang, Haidy G Nasief, Sarah Kohn, Andy Milkowski, Tom Clary, Stephen Barnes, Paul E Barbone, Timothy J Hall
Ultrasound elasticity imaging has demonstrated utility in breast imaging, but it is typically performed with handheld transducers and two-dimensional imaging. Two-dimensional (2D) elastography images tissue stiffness of only a plane and hence suffers from errors due to out-of-plane motion, whereas three-dimensional (3D) data acquisition and motion tracking can be used to track out-of-plane motion that is lost in 2D elastography systems. A commercially available automated breast volume scanning system that acquires 3D ultrasound data with precisely controlled elevational movement of the 1D array ultrasound transducer was employed in this study...
June 1, 2017: Ultrasonic Imaging
https://www.readbyqxmd.com/read/28580706/mr-techniques-for-guiding-high-intensity-focused-ultrasound-hifu-treatments
#18
REVIEW
Kagayaki Kuroda
To make full use of the ability of magnetic resonance (MR) to guide high-intensity focused ultrasound (HIFU) treatment, effort has been made to improve techniques for thermometry, motion tracking, and sound beam visualization. For monitoring rapid temperature elevation with proton resonance frequency (PRF) shift, data acquisition and processing can be accelerated with parallel imaging and/or sparse sampling in conjunction with appropriate signal processing methods. Thermometry should be robust against tissue motion, motion-induced magnetic field variation, and susceptibility change...
June 5, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28580597/false-fmri-activation-after-motion-correction
#19
Renat Yakupov, Juan Lei, Michael Hoffmann, Oliver Speck
Motion correction of echo-planar imaging (EPI) data used in functional MRI (fMRI) is an essential preprocessing step performed prior to statistical analysis. At ultra-high resolution fMRI, current requirements regarding translational and rotational motion may no longer be acceptable. This prompts the need for a systematic investigation of the effects of motion correction procedures with in vivo fMRI data. Here we systematically evaluated the effect of retrospective motion correction with freely available fMRI analysis software packages (FSL, AFNI, and SPM) on activation maps using fMRI data acquired with prospective motion detection, to identify and quantify confounding effects of retrospective motion correction, and to evaluate its dependence on spatial resolution and motion correction algorithms...
June 5, 2017: Human Brain Mapping
https://www.readbyqxmd.com/read/28553198/a-resilient-non-neuronal-source-of-the-spatiotemporal-lag-structure-detected-by-bold-signal-based-blood-flow-tracking
#20
Toshihiko Aso, Guanhua Jiang, Shin-Ichi Urayama, Hidenao Fukuyama
Recent evidence has suggested that blood oxygenation level-dependent (BOLD) signals convey information about brain circulation via low frequency oscillation of systemic origin (sLFO) that travels through the vascular structure ("lag mapping"). Prompted by its promising application in both physiology and pathology, we examined this signal component using multiple approaches. A total of 30 healthy volunteers were recruited to perform two reproducibility experiments at 3 Tesla using multiband echo planar imaging...
2017: Frontiers in Neuroscience
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