In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

Science.gov (United States)

Nillesen, M. M.; Lopata, R. G. P.; de Boode, W. P.; Gerrits, I. H.; Huisman, H. J.; Thijssen, J. M.; Kapusta, L.; de Korte, C. L.

2009-04-01

Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

Adult echocardiographic nomograms: overview, critical review and creation of a software for automatic, fast and easy calculation of normal values.

Science.gov (United States)

Cantinotti, Massimiliano; Giordano, Raffaele; Paterni, Marco; Saura, Daniel; Scalese, Marco; Franchi, Eliana; Assanta, Nadia; Koestenberg, Martin; Dulgheru, Raluca; Sugimoto, Tadafumi; Bernard, Anne; Caballero, Luis; Lancellotti, Patrizio

2017-12-01

There is a crescent interest on normal adult echocardiographic values and the introduction of new deformation imaging and 3D parameters pose the issue of normative data. A multitude of nomograms has been recently published, however data are often fragmentary, difficult to find, and their strengths/limitations have been never evaluated. (I) to provide a review of current echocardiographic nomograms; (II) to generate a tool for easy and fast access to these data. A literature search was conducted accessing the National Library of Medicine using the keywords: 2D/3D echocardiography, strain, left/right ventricle, atrial, mitral/tricuspid valve, aorta, reference values/nomograms/normal values. Adding the following keywords, the results were further refined: range/intervals, myocardial velocity, strain rate and speckle tracking. Forty one published studies were included. Our study reveals that for several of 2D/3D parameters sufficient normative data exist, however, a few limitations still persist. For some basic parameters (i.e., mitral/tricuspid/pulmonary valves, great vessels) and for 3D valves data are scarce. There is a lack of studies evaluating ethnic differences. Data have been generally expressed as mean values normalised for gender and age instead of computing models incorporating different variables (age/gender/body sizes) to calculate z scores. To summarize results a software ( Echocardio-Normal Values ) who automatically calculate range of normality for a broad range of echocardiographic measurements according to age/gender/weight/height, has been generated. We provide an up-to-date and critical review of strengths/limitation of current adult echocardiographic nomograms. Furthermore we generated a software for automatic, easy and fast access to multiple echocardiographic normative data.

Anomalous Aortic Origin of Coronary Arteries in the Young: Echocardiographic Evaluation With Surgical Correlation.

Science.gov (United States)

Lorber, Richard; Srivastava, Shubhika; Wilder, Travis J; McIntyre, Susan; DeCampli, William M; Williams, William G; Frommelt, Peter C; Parness, Ira A; Blackstone, Eugene H; Jacobs, Marshall L; Mertens, Luc; Brothers, Julie A; Herlong, J René

2015-11-01

This study sought to compare findings from institutional echocardiographic reports with imaging core laboratory (ICL) review of corresponding echocardiographic images and operative reports in 159 patients with anomalous aortic origin of a coronary artery (AAOCA). The study also sought to develop a "best practice" protocol for imaging and interpreting images in establishing the diagnosis of AAOCA. AAOCA is associated with sudden death in the young. Underlying anatomic risk factors that can cause ischemia-related events include coronary arterial ostial stenosis, intramural course of the proximal coronary within the aortic wall, interarterial course, and potential compression between the great arteries. Consistent protocols for diagnosing and evaluating these features are lacking, potentially precluding the ability to risk stratify patients based on evidence and plan surgical strategy. For a prescribed set of anatomic AAOCA features, percentages of missing data in institutional echocardiographic reports were calculated. For each feature, agreement among institutional echocardiographic reports, ICL review of images, and surgical reports was evaluated using the weighted kappa statistic. An echocardiographic imaging protocol was developed heuristically to reduce differences between institutional reports and ICL review. A total of 13%, 33%, and 62% of echocardiograms were missing images enabling diagnosis of intra-arterial course, proximal intramural course, and high ostial takeoff, respectively. There was poor agreement between institutional reports and ICL review for diagnosis of origin of coronary artery, interarterial course, intramural course, and acute angle takeoff (kappa = 0.74, 0.11, -0.03, 0.13, respectively). Surgical findings were also significantly different from those of reports, and to a lesser extent ICL reviews. The resulting protocol contains technical recommendations for imaging each of these features. Poor agreement between institutional reports and

Echocardiographic phase imaging to predict reverse remodeling after cardiac resynchronization therapy.

Science.gov (United States)

Buss, Sebastian J; Humpert, Per M; Bekeredjian, Raffi; Hardt, Stefan E; Zugck, Christian; Schellberg, Dieter; Bauer, Alexander; Filusch, Arthur; Kuecherer, Helmut; Katus, Hugo A; Korosoglou, Grigorios

2009-05-01

The aim of our study was to investigate whether echocardiographic phase imaging (EPI) can predict response in patients who are considered for cardiac resynchronization therapy (CRT). CRT improves quality of life, exercise capacity, and outcome in patients with bundle-branch block and advanced heart failure. Previous studies used QRS duration to select patients for CRT; the accuracy of this parameter to predict functional recovery, however, is controversial. We examined 42 patients with advanced heart failure (New York Heart Association [NYHA] functional class III to IV, QRS duration >130 ms, and ejection fraction or=15% at 6 to 8 months of follow-up were defined as responders. All others were classified as nonresponders. The Ts-SD and the mean EPI-Index were related to Delta ESV (r = 0.43 for Ts-SD and r = 0.67 for mean EPI-Index, p < 0.01 for both), and both parameters yielded similar accuracy for the prediction of LV remodeling (area under the curve of 0.87 for TDI vs. 0.90 for EPI, difference between areas = 0.03, p = NS) and ejection fraction (EF) improvement (area under the curve of 0.87 for TDI vs. 0.93 for EPI, difference between areas = 0.06, p = NS). Furthermore, patients classified as responders by EPI (mean EPI-Index Echocardiographic phase imaging can predict functional recovery, reverse LV remodeling, and clinical outcomes in patients who undergo CRT. EPI is a method that objectively and accurately quantifies LV dyssynchrony and seems to be noninferior to TDI for the prediction of reverse LV remodeling and functional recovery.

Electrocardiographic left ventricular hypertrophy without echocardiographic abnormalities evaluated by myocardial perfusion and fatty acid metabolic imaging

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi

2000-01-01

The pathophysiologic process in patients with electrocardiographic left ventricular hypertrophy with ST, T changes but without echocardiographic abnormalities was investigated by myocardial perfusion imaging and fatty acid metabolic imaging. Exercise stress 99m Tc-methoxy-isobutyl isonitrile (MIBI) imaging and rest 123 I-beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP) imaging were performed in 59 patients with electrocardiographic hypertrophy including 29 without apparent cause including hypertension and echocardiographic hypertrophy, and 30 with essential hypertension. Coronary angiography was performed in 6 patients without hypertension and 4 with hypertension and biopsy specimens were obtained from the left ventricular apex from 6 patients without hypertension. Myocardial perfusion and 123 I-BMIPP images were classified into 3 types: normal, increased accumulation of the isotope at the left ventricular apex (high uptake) and defect. Transient perfusion abnormality and apical defect observed by 123 I-BMIPP imaging were more frequent in patients without hypertension than in patients with hypertension (32% vs. 17%, p=0.04671 in perfusion; 62% vs. 30%, p=0.0236 in 123 I-BMIPP). Eighteen normotensive patients with apical defect by 123 I-BMIPP imaging included 3 of 10 patients with normal perfusion at exercise, 6 of 10 patients with high uptake and 9 of 9 patients with perfusion defect. The defect size revealed by 123 I-BMIPP imaging was greater than that of the perfusion abnormality. Coronary stenoses were not observed and myocardial specimens showed myocardial disarray with hypertrophy. Moreover, 9 patients with hypertension and apical defects by 123 I-BMIPP showed 3 different types of perfusion. Many patients without hypertension show a pathologic process similar to hypertrophic cardiomyopathy. Perfusion and 123 I-BMIPP imaging are useful for the identification of these patients. (author)

Comparison of echocardiographic findings in patients with nonfunctioning adrenal incidentalomas

Directory of Open Access Journals (Sweden)

Narin Nasıroglu Imga

2017-06-01

Full Text Available Adrenal incidentalomas (AIs are usually discovered incidentally after imaging unrelated to adrenal glands. We aimed to evaluate standard risk factors for systemic atherosclerosis and echocardiographic changes in patients with nonfunctioning AIs and compare them with normal subjects. We evaluated 70 patients diagnosed with AIs and 51 healthy controls. Mean levels were determined for HbA1c, LDL, uric acid, fasting plasma insulin, HOMA, and neutrophil-to-lymphocyte ratio (NLR, and these values were found to be significantly higher in the patients than the controls. The mean left atrial diameter, interventricular septum thickness, posterior wall thickness, left ventricular mass, E-wave deceleration time, isovolumetric relaxation time, and the median ratio of the early transmittal flow velocity to the early diastolic tissue velocity (E/Em were higher in patients with AIs compared to controls. The mitral annular early diastolic velocity was lower in patients with AIs. The mean aortic diastolic diameter, stiffness index (SI, and aortic strain were higher, and aortic distensibility was lower in the patients. The mean right ventricular diameter, right atrial major-axis diameter, and right atrial minor-axis diameter were statistically higher in the patient group than the controls. A negative correlation was found between the NLR and aortic strain and aortic distensibility, while a positive correction was found between the NLR and SI. We found altered left ventricular (LV and right ventricular (RV echocardiographic findings in patients with AIs without known cardiovascular disease. Aortic stiffness was also increased. These changes may be related to an increase in cardiovascular risk factors in AI patients.

Dynamic three-dimensional display of common congenital cardiac defects from reconstruction of two-dimensional echocardiographic images.

Science.gov (United States)

Hsieh, K S; Lin, C C; Liu, W S; Chen, F L

1996-01-01

Two-dimensional echocardiography had long been a standard diagnostic modality for congenital heart disease. Further attempts of three-dimensional reconstruction using two-dimensional echocardiographic images to visualize stereotypic structure of cardiac lesions have been successful only recently. So far only very few studies have been done to display three-dimensional anatomy of the heart through two-dimensional image acquisition because such complex procedures were involved. This study introduced a recently developed image acquisition and processing system for dynamic three-dimensional visualization of various congenital cardiac lesions. From December 1994 to April 1995, 35 cases were selected in the Echo Laboratory here from about 3000 Echo examinations completed. Each image was acquired on-line with specially designed high resolution image grazmber with EKG and respiratory gating technique. Off-line image processing using a window-architectured interactive software package includes construction of 2-D ehcocardiographic pixel to 3-D "voxel" with conversion of orthogonal to rotatory axial system, interpolation, extraction of region of interest, segmentation, shading and, finally, 3D rendering. Three-dimensional anatomy of various congenital cardiac defects was shown, including four cases with ventricular septal defects, two cases with atrial septal defects, and two cases with aortic stenosis. Dynamic reconstruction of a "beating heart" is recorded as vedio tape with video interface. The potential application of 3D display of the reconstruction from 2D echocardiographic images for the diagnosis of various congenital heart defects has been shown. The 3D display was able to improve the diagnostic ability of echocardiography, and clear-cut display of the various congenital cardiac defects and vavular stenosis could be demonstrated. Reinforcement of current techniques will expand future application of 3D display of conventional 2D images.

Graph cut-based method for segmenting the left ventricle from MRI or echocardiographic images.

Science.gov (United States)

Bernier, Michael; Jodoin, Pierre-Marc; Humbert, Olivier; Lalande, Alain

2017-06-01

In this paper, we present a fast and interactive graph cut method for 3D segmentation of the endocardial wall of the left ventricle (LV) adapted to work on two of the most widely used modalities: magnetic resonance imaging (MRI) and echocardiography. Our method accounts for the fundamentally different nature of both modalities: 3D echocardiographic images have a low contrast, a poor signal-to-noise ratio and frequent signal drop, while MR images are more detailed but also cluttered and contain highly anisotropic voxels. The main characteristic of our method is to work in a 3D Bezier coordinate system instead of the original Euclidean space. This comes with several advantages, including an implicit shape prior and a result guarantied not to have any holes in it. The proposed method is made of 4 steps. First, a 3D sampling of the LV cavity is made based on a Bezier coordinate system. This allows to warp the input 3D image to a Bezier space in which a plane corresponds to an anatomically plausible 3D Euclidean bullet shape. Second, a 3D graph is built and an energy term (which is based on the image gradient and a 3D probability map) is assigned to each edge of the graph, some of which being given an infinite energy to ensure the resulting 3D structure passes through key anatomical points. Third, a max-flow min-cut procedure is executed on the energy graph to delineate the endocardial surface. And fourth, the resulting surface is projected back to the Euclidean space where a post-processing convex hull algorithm is applied on every short axis slice to remove local concavities. Results obtained on two datasets reveal that our method takes between 2 and 5s to segment a 3D volume, it has better results overall than most state-of-the-art methods on the CETUS echocardiographic dataset and is statistically as good as a human operator on MR images. Copyright © 2017 Elsevier Ltd. All rights reserved.

Echocardiographic anatomy of the mitral valve: a critical appraisal of 2-dimensional imaging protocols with a 3-dimensional perspective.

Science.gov (United States)

Mahmood, Feroze; Hess, Philip E; Matyal, Robina; Mackensen, G Burkhard; Wang, Angela; Qazi, Aisha; Panzica, Peter J; Lerner, Adam B; Maslow, Andrew

2012-10-01

To highlight the limitations of traditional 2-dimensional (2D) echocardiographic mitral valve (MV) examination methodologies, which do not account for patient-specific transesophageal echocardiographic (TEE) probe adjustments made during an actual clinical perioperative TEE examination. Institutional quality-improvement project. Tertiary care hospital. Attending anesthesiologists certified by the National Board of Echocardiography. Using the technique of multiplanar reformatting with 3-dimensional (3D) data, ambiguous 2D images of the MV were generated, which resembled standard midesophageal 2D views. Based on the 3D image, the MV scallops visualized in each 2D image were recognized exactly by the position of the scan plane. Twenty-three such 2D MV images were created in a presentation from the 3D datasets. Anesthesia staff members (n = 13) were invited to view the presentation based on the 2D images only and asked to identify the MV scallops. Their responses were scored as correct or incorrect based on the 3D image. The overall accuracy was 30.4% in identifying the MV scallops. The transcommissural view was identified correctly >90% of the time. The accuracy of the identification of A1, A3, P1, and P3 scallops was <50%. The accuracy of the identification of A2P2 scallops was ≥50%. In the absence of information on TEE probe adjustments performed to acquire a specific MV image, it is possible to misidentify the scallops. Copyright © 2012 Elsevier Inc. All rights reserved.

Automated segmentation and geometrical modeling of the tricuspid aortic valve in 3D echocardiographic images.

Science.gov (United States)

Pouch, Alison M; Wang, Hongzhi; Takabe, Manabu; Jackson, Benjamin M; Sehgal, Chandra M; Gorman, Joseph H; Gorman, Robert C; Yushkevich, Paul A

2013-01-01

The aortic valve has been described with variable anatomical definitions, and the consistency of 2D manual measurement of valve dimensions in medical image data has been questionable. Given the importance of image-based morphological assessment in the diagnosis and surgical treatment of aortic valve disease, there is considerable need to develop a standardized framework for 3D valve segmentation and shape representation. Towards this goal, this work integrates template-based medial modeling and multi-atlas label fusion techniques to automatically delineate and quantitatively describe aortic leaflet geometry in 3D echocardiographic (3DE) images, a challenging task that has been explored only to a limited extent. The method makes use of expert knowledge of aortic leaflet image appearance, generates segmentations with consistent topology, and establishes a shape-based coordinate system on the aortic leaflets that enables standardized automated measurements. In this study, the algorithm is evaluated on 11 3DE images of normal human aortic leaflets acquired at mid systole. The clinical relevance of the method is its ability to capture leaflet geometry in 3DE image data with minimal user interaction while producing consistent measurements of 3D aortic leaflet geometry.

Laser-induced photo-thermal strain imaging

Science.gov (United States)

Choi, Changhoon; Ahn, Joongho; Jeon, Seungwan; Kim, Chulhong

2018-02-01

Vulnerable plaque is the one of the leading causes of cardiovascular disease occurrence. However, conventional intravascular imaging techniques suffer from difficulty in finding vulnerable plaque due to limitation such as lack of physiological information, imaging depth, and depth sensitivity. Therefore, new techniques are needed to help determine the vulnerability of plaque, Thermal strain imaging (TSI) is an imaging technique based on ultrasound (US) wave propagation speed that varies with temperature of medium. During temperature increase, strain occurs in the medium and its variation tendency is depending on the type of tissue, which makes it possible to use for tissue differentiation. Here, we demonstrate laser-induced photo-thermal strain imaging (pTSI) to differentiate tissue using an intravascular ultrasound (IVUS) catheter and a 1210-nm continuous-wave laser for heating lipids intensively. During heating, consecutive US images were obtained from a custom-made phantom made of porcine fat and gelatin. A cross correlation-based speckle-tracking algorithm was then applied to calculate the strain of US images. In the strain images, the positive strain produced in lipids (porcine fat) was clearly differentiated from water-bearing tissue (gelatin). This result shows that laser-induced pTSI could be a new method to distinguish lipids in the plaque and can help to differentiate vulnerability of plaque.

A 29-year-old Harken disk mitral valve: long-term follow-up by echocardiographic and cineradiographic imaging.

Science.gov (United States)

Hsi, David H; Ryan, Gerald F; Taft, Janice; Arnone, Thomas J

2003-01-01

An 81-year-old woman was evaluated for prosthetic mitral valve function. She had received a Harken disk mitral valve 29 years earlier due to severe mitral valve disease. This particular valve prosthesis is known for premature disk edge wear and erosion. The patients 2-dimensional Doppler echocardiogram showed the distinctive appearance of a disk mitral valve prosthesis. Color Doppler in diastole showed a unique crown appearance, with initial flow acceleration around the disk followed by convergence to laminar flow in the left ventricle. Cineradiographic imaging revealed normal valve function and minimal disk erosion. We believe this to be the longest reported follow-up of a surviving patient with a rare Harken disk valve. We present images with unique echocardiographic and cineangiographic features.

Optimisation of coronary vascular territorial 3D echocardiographic strain imaging using computed tomography

DEFF Research Database (Denmark)

de Knegt, Martina Chantal; Fuchs, A; Weeke, P

2016-01-01

alignment was assessed by 3 readers using a 4-point scale. Territorial LS was assessed using the 17-segment model and the MDCT-guided vascular model in territories supplied by significantly stenotic and non-significantly stenotic vessels. Successful 3DE/MDCT image alignment was obtained in 86 and 93...... % of cases for reader one, and reader two and three, respectively. Fair agreement on the quality of automatic image alignment (intra-class correlation = 0.40) and the success of manual image alignment (Fleiss' Kappa = 0.40) among the readers was found. In territories supplied by non-significantly stenotic...... day followed by invasive coronary angiography. MDCT (Aquilion ONE, ViSION Edition, Toshiba Medical Systems) and 3DE apical full-volume images (Artida, Toshiba Medical Systems) were fused offline using a dedicated workstation (prototype fusion software, Toshiba Medical Systems). 3DE/MDCT image...

Quantitative echocardiographic measures in the assessment of single ventricle function post-Fontan: Incorporation into routine clinical practice.

Science.gov (United States)

Rios, Rodrigo; Ginde, Salil; Saudek, David; Loomba, Rohit S; Stelter, Jessica; Frommelt, Peter

2017-01-01

Quantitative echocardiographic measurements of single ventricular (SV) function have not been incorporated into routine clinical practice. A clinical protocol, which included quantitative measurements of SV deformation (global circumferential and longitudinal strain and strain rate), standard deviation of time to peak systolic strain, myocardial performance index (MPI), dP/dT from an atrioventricular valve regurgitant jet, and superior mesenteric artery resistance index, was instituted for all patients with a history of Fontan procedure undergoing echocardiography. All measures were performed real time during clinically indicated studies and were included in clinical reports. A total of 100 consecutive patients (mean age = 11.95±6.8 years, range 17 months-31.3 years) completed the protocol between September 1, 2014 to April 29, 2015. Deformation measures were completed in 100% of the studies, MPI in 93%, dP/dT in 55%, and superior mesenteric artery Doppler in 82%. The studies were reviewed to assess for efficiency in completing the protocol. The average time for image acquisition was 27.4±8.8 (range 10-62 minutes). The average time to perform deformation measures was 10.8±5.5 minutes (range 5-35 minutes) and time from beginning of imaging to report completion was 53.4±13.7 minutes (range 27-107 minutes). There was excellent inter-observer reliability when deformation indices were blindly repeated. Patients with a single left ventricle had significantly higher circumferential strain and strain rate, longitudinal strain and strain rate, and dP/dT compared to a single right ventricle. There were no differences in quantitative indices of ventricular function between patients 10 years post-Fontan. Advanced quantitative assessment of SV function post-Fontan can be consistently and efficiently performed real time during clinically indicated echocardiograms with excellent reliability. © 2016, Wiley Periodicals, Inc.

Echocardiographic assessment of the right ventricle in the current era: Application in clinical practice.

Science.gov (United States)

Venkatachalam, Sridhar; Wu, Geru; Ahmad, Masood

2017-12-01

The right ventricle has unique structural and functional characteristics. It is now well recognized that the so-called forgotten ventricle is a key player in cardiovascular physiology. Furthermore, there is accumulating evidence that demonstrates right ventricular dysfunction as an important marker of morbidity and mortality in several commonly encountered clinical situations such as heart failure, pulmonary hypertension, pulmonary embolism, right ventricular myocardial infarction, and adult congenital heart disease. In contrast to the left ventricle, echocardiographic assessment of right ventricular function is more challenging as volume estimations are not possible without the use of three-dimensional (3D) echocardiography. Guidelines on chamber quantification provide a standardized approach to assessment of the right ventricle. The technique and limitations of each of the parameters for RV size and function need to be fully understood. In this era of multimodality imaging, echocardiography continues to remain a useful tool for the initial assessment and follow-up of patients with right heart pathology. Several novel approaches such as 3D and strain imaging of the right ventricle have expanded the usefulness of this indispensable modality. © 2017, Wiley Periodicals, Inc.

The septal bulge--an early echocardiographic sign in hypertensive heart disease.

Science.gov (United States)

Gaudron, Philipp Daniel; Liu, Dan; Scholz, Friederike; Hu, Kai; Florescu, Christiane; Herrmann, Sebastian; Bijnens, Bart; Ertl, Georg; Störk, Stefan; Weidemann, Frank

2016-01-01

Patients in the early stage of hypertensive heart disease tend to have normal echocardiographic findings. The aim of this study was to investigate whether pathology-specific echocardiographic morphologic and functional parameters can help to detect subclinical hypertensive heart disease. One hundred ten consecutive patients without a history and medication for arterial hypertension (AH) or other cardiac diseases were enrolled. Standard echocardiography and two-dimensional speckle-tracking-imaging analysis were performed. Resting blood pressure (BP) measurement, cycle ergometer test (CET), and 24-hour ambulatory BP monitoring (ABPM) were conducted. Patients were referred to "septal bulge (SB)" group (basal-septal wall thickness ≥ 2 mm thicker than mid-septal wall thickness) or "no-SB" group. Echocardiographic SB was found in 48 (43.6%) of 110 patients. In this SB group, 38 (79.2%) patients showed AH either by CET or ABPM. In contrast, in the no-SB group (n = 62), 59 (95.2%) patients had no positive test for AH by CET or ABPM. When AH was solely defined by resting BP, SB was a reasonable predictive sign for AH (sensitivity 73%, specificity 76%). However, when AH was confirmed by CET or ABPM the echocardiographic SB strongly predicted clinical AH (sensitivity 93%, specificity 86%). In addition, regional myocardial deformation of the basal-septum in SB group was significantly lower than in no-SB group (14 ± 4% vs. 17 ± 4%; P heart disease. Sophisticated BP evaluation including resting BP, ABPM, and CET should be performed in all patients with an accidental finding of a SB in echocardiography. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Longitudinal strain bull's eye plot patterns in patients with cardiomyopathy and concentric left ventricular hypertrophy.

Science.gov (United States)

Liu, Dan; Hu, Kai; Nordbeck, Peter; Ertl, Georg; Störk, Stefan; Weidemann, Frank

2016-05-10

Despite substantial advances in the imaging techniques and pathophysiological understanding over the last decades, identification of the underlying causes of left ventricular hypertrophy by means of echocardiographic examination remains a challenge in current clinical practice. The longitudinal strain bull's eye plot derived from 2D speckle tracking imaging offers an intuitive visual overview of the global and regional left ventricular myocardial function in a single diagram. The bull's eye mapping is clinically feasible and the plot patterns could provide clues to the etiology of cardiomyopathies. The present review summarizes the longitudinal strain, bull's eye plot features in patients with various cardiomyopathies and concentric left ventricular hypertrophy and the bull's eye plot features might serve as one of the cardiac workup steps on evaluating patients with left ventricular hypertrophy.

Cardiac strain findings in children with latent rheumatic heart disease detected by echocardiographic screening.

Science.gov (United States)

Beaton, Andrea; Richards, Hedda; Ploutz, Michelle; Gaur, Lasya; Aliku, Twalib; Lwabi, Peter; Ensing, Greg; Sable, Craig

2017-08-01

Identification of patients with latent rheumatic heart disease by echocardiography presents a unique opportunity to prevent disease progression. Myocardial strain is a more sensitive indicator of cardiac performance than traditional measures of systolic function. The objective of this study was to test the hypothesis that abnormalities in myocardial strain may be present in children with latent rheumatic heart disease. Standard echocardiography images with electrocardiogram gating were obtained from Ugandan children found to have latent rheumatic heart disease as well as control subjects. Traditional echocardiography measures of systolic function were obtained, and offline global longitudinal strain analysis was performed. Comparison between groups was performed using strain as a continuous (Mann-Whitney U-test) and categorical (cut-off 5th percentile for age) variable. Our study included 14 subjects with definite rheumatic heart disease, 13 with borderline rheumatic heart disease, and 112 control subjects. None of the subjects had abnormal left ventricular size or ejection fraction. Global longitudinal strain was lower than the 5th percentile in 44% of the subjects with any rheumatic heart disease (p=0.002 versus controls) and 57% of the subjects with definite rheumatic heart disease (p=0.03). The mean absolute strain values were significantly lower when comparing subjects with any rheumatic heart disease with controls (20.4±3.95 versus 22.4±4.35, p=0.025) and subjects with definite rheumatic heart disease with controls (19.9±4.25 versus 22.4±4.35, p=0.033). Global longitudinal strain is decreased in subjects with rheumatic heart disease in the absence of abnormal systolic function. Larger studies with longer-term follow-up are required to determine whether there is a role for strain to help better understand the pathophysiology of latent rheumatic heart disease.

Ultrasound strain imaging using Barker code

Science.gov (United States)

Peng, Hui; Tie, Juhong; Guo, Dequan

2017-01-01

Ultrasound strain imaging is showing promise as a new way of imaging soft tissue elasticity in order to help clinicians detect lesions or cancers in tissues. In this paper, Barker code is applied to strain imaging to improve its quality. Barker code as a coded excitation signal can be used to improve the echo signal-to-noise ratio (eSNR) in ultrasound imaging system. For the Baker code of length 13, the sidelobe level of the matched filter output is -22dB, which is unacceptable for ultrasound strain imaging, because high sidelobe level will cause high decorrelation noise. Instead of using the conventional matched filter, we use the Wiener filter to decode the Barker-coded echo signal to suppress the range sidelobes. We also compare the performance of Barker code and the conventional short pulse in simulation method. The simulation results demonstrate that the performance of the Wiener filter is much better than the matched filter, and Baker code achieves higher elastographic signal-to-noise ratio (SNRe) than the short pulse in low eSNR or great depth conditions due to the increased eSNR with it.

Echocardiographic agreement in the diagnostic evaluation for infective endocarditis

DEFF Research Database (Denmark)

Lauridsen, Trine Kiilerich; Selton-Suty, Christine; Tong, Steven Y C

2016-01-01

Echocardiography is essential for the diagnosis and management of infective endocarditis (IE). However, the reproducibility for the echocardiographic assessment of variables relevant to IE is unknown. Objectives of this study were: (1) To define the reproducibility for IE echocardiographic...... variables and (2) to describe a methodology for assessing quality in an observational cohort containing site-interpreted data. IE reproducibility was assessed on a subset of echocardiograms from subjects enrolled in the International Collaboration on Endocarditis registry. Specific echocardiographic case...

Development and Implementation of a Quality Improvement Process for Echocardiographic Laboratory Accreditation.

Science.gov (United States)

Gilliland, Yvonne E; Lavie, Carl J; Ahmad, Homaa; Bernal, Jose A; Cash, Michael E; Dinshaw, Homeyar; Milani, Richard V; Shah, Sangeeta; Bienvenu, Lisa; White, Christopher J

2016-03-01

We describe our process for quality improvement (QI) for a 3-year accreditation cycle in echocardiography by the Intersocietal Accreditation Commission (IAC) for a large group practice. Echocardiographic laboratory accreditation by the IAC was introduced in 1996, which is not required but could impact reimbursement. To ensure high-quality patient care and community recognition as a facility committed to providing high-quality echocardiographic services, we applied for IAC accreditation in 2010. Currently, there is little published data regarding the IAC process to meet echocardiography standards. We describe our approach for developing a multicampus QI process for echocardiographic laboratory accreditation during the 3-year cycle of accreditation by the IAC. We developed a quarterly review assessing (1) the variability of the interpretations, (2) the quality of the examinations, (3) a correlation of echocardiographic studies with other imaging modalities, (4) the timely completion of reports, (5) procedure volume, (6) maintenance of Continuing Medical Education credits by faculty, and (7) meeting Appropriate Use Criteria. We developed and implemented a multicampus process for QI during the 3-year accreditation cycle by the IAC for Echocardiography. We documented both the process and the achievement of those metrics by the Echocardiography Laboratories at the Ochsner Medical Institutions. We found the QI process using IAC standards to be a continuous educational experience for our Echocardiography Laboratory physicians and staff. We offer our process as an example and guide for other echocardiography laboratories who wish to apply for such accreditation or reaccreditation. © 2016, Wiley Periodicals, Inc.

2D-speckle tracking right ventricular strain to assess right ventricular systolic function in systolic heart failure. Analysis of the right ventricular free and posterolateral walls.

Science.gov (United States)

Mouton, Stéphanie; Ridon, Héléne; Fertin, Marie; Pentiah, Anju Duva; Goémine, Céline; Petyt, Grégory; Lamblin, Nicolas; Coisne, Augustin; Foucher-Hossein, Claude; Montaigne, David; de Groote, Pascal

2017-10-15

Right ventricular (RV) systolic function is a powerful prognostic factor in patients with systolic heart failure. The accurate estimation of RV function remains difficult. The aim of the study was to determine the diagnostic accuracy of 2D-speckle tracking RV strain in patients with systolic heart failure, analyzing both free and posterolateral walls. Seventy-six patients with dilated cardiopathy (left ventricular end-diastolic volume≥75ml/m 2 ) and left ventricular ejection fraction≤45% had an analysis of the RV strain. Feasibility, reproducibility and diagnostic accuracy of RV strain were analyzed and compared to other echocardiographic parameters of RV function. RV dysfunction was defined as a RV ejection fraction≤40% measured by radionuclide angiography. RV strain feasibility was 93.9% for the free-wall and 79.8% for the posterolateral wall. RV strain reproducibility was good (intra-observer and inter-observer bias and limits of agreement of 0.16±1.2% [-2.2-2.5] and 0.84±2.4 [-5.5-3.8], respectively). Patients with left heart failure have a RV systolic dysfunction that can be unmasked by advanced echocardiographic imaging: mean RV strain was -21±5.7% in patients without RV dysfunction and -15.8±5.1% in patients with RV dysfunction (p=0.0001). Mean RV strain showed the highest diagnostic accuracy to predict depressed RVEF (area under the curve (AUC) 0.75) with moderate sensitivity (60.5%) but high specificity (87.5%) using a cutoff value of -16%. RV strain seems to be a promising and more efficient measure than previous RV echocardiographic parameters for the diagnosis of RV systolic dysfunction. Copyright © 2017 Elsevier B.V. All rights reserved.

Real-Time Implementation of Medical Ultrasound Strain Imaging System

International Nuclear Information System (INIS)

Jeong, Mok Kun; Kwon, Sung Jae; Bae, Moo Ho

2008-01-01

Strain imaging in a medical ultrasound imaging system can differentiate the cancer or tumor in a lesion that is stiffer than the surrounding tissue. In this paper, a strain imaging technique using quasistatic compression is implemented that estimates the displacement between pre- and postcompression ultrasound echoes and obtains strain by differentiating it in the spatial direction. Displacements are computed from the phase difference of complex baseband signals obtained using their autocorrelation, and errors associated with converting the phase difference into time or distance are compensated for by taking into the center frequency variation. Also, to reduce the effect of operator's hand motion, the displacements of all scanlines are normalized with the result that satisfactory strain image quality has been obtained. These techniques have been incorporated into implementing a medical ultrasound strain imaging system that operates in real time.

Echocardiographic evaluation of the arterial stiffness in healthy subjects and hypertensive patients under 60 years

International Nuclear Information System (INIS)

Valiente Mustelier, Juan; Suarez Vazquez, Leisy; Cabrera Rego, Julio Oscar; Gandarilla Sarmientos, Julio Cesar

2011-01-01

We conducted a cross-sectional study that included 83 patients (healthy, n=43; hypertensive, n=40) assisted in the external consultation of the National Cardiology and Cardiovascular Surgery Institute, from April to October, 2009. We included clinical (age, sex, personal antecedents of smoking habit, obesity, hypercholesterolemia, arterial hypertension) and echocardiographic (diastolic function, arterial stiffness index [β], pressure strain elastic modulus [Ep], arterial compliance, local pulse wave velocity [LPWV]) variables

ECHOCARDIOGRAPHIC DIAGNOSTICS OF CARCINOID HEART DISEASE

Directory of Open Access Journals (Sweden)

Janez Ravnik

2002-09-01

Full Text Available Background. Carcinoid heart disease is a rare heart disease which affects endocard and heart valves on the right side of heart. It affects only patients with manifested carcinoid syndrome, which is thought to be the consequence of secretory active metastases of carcinoid tumour. The carcinoid endocardial plaques cause structural changes of tricuspid and pulmonic valve and later on their stenosis and/or insufficiency.Patients and methods. In this article we introduce a carcinoid valve heart disease (CVHD scoring system for easier end exact echocardiographic diagnostics. Four echocardiographic parameters are beeing estimated: structural changes of tricuspid valve, tricuspid valve regurgitation, stenosis of pulmonic valve and pulmonic valve regurgitation.Conclusions. The scoring system allows us to make an early diagnosis and evaluation of progression of carcinoid heart disease, which is very important for planning the treatment process. Our experiences confirm the usefulness of this scoring system in echocardiographic follow–up of patients with carcinoid syndrome.

Echocardiographic abnormalities in hypertensive patients

International Nuclear Information System (INIS)

Rodulfo Garcia, Maikel; Tornes Perez, Victor Manuel; Castellanos Tardo, Juan Ramon

2012-01-01

A descriptive cross-sectional study was carried out in 120 hypertensive patients with a course of 5 or more years, who went to the emergency room of 'Saturnino Lora' Provincial Teaching Hospital from November 2010 to November 2011 in order to determine the presence or absence of echocardiographic abnormalities typical of hypertension. Of these, 78,3 % was affected, most of whom reported not to continue with regular previous medical treatment, and 21,7 % had not these abnormalities. Age group of 50-60 years, males and blacks prevailed in the case material. The most significant echocardiographic findings were left ventricular hypertrophy and heart failure with ejection fraction of left ventricle preserved

Myocardial left ventricular dysfunction in patients with systemic lupus erythematosus: new insights from tissue Doppler and strain imaging.

Science.gov (United States)

Buss, Sebastian J; Wolf, David; Korosoglou, Grigorios; Max, Regina; Weiss, Celine S; Fischer, Christian; Schellberg, Dieter; Zugck, Christian; Kuecherer, Helmut F; Lorenz, Hanns-Martin; Katus, Hugo A; Hardt, Stefan E; Hansen, Alexander

2010-01-01

Systemic lupus erythematosus (SLE) is associated with high cardiovascular morbidity and mortality. Cardiovascular involvement is frequently underestimated by routine imaging techniques. Our aim was to determine if new echocardiographic imaging modalities like tissue Doppler (TDI), strain rate (SRR), and strain (SRI) imaging detect abnormalities in left ventricular (LV) function in asymptomatic patients with SLE. Sixty-seven young patients with SLE (mean age 42 +/- 10 yrs) without typical symptoms or signs of heart failure or angina, and a matched healthy control group (n = 40), underwent standard transthoracic echocardiography, TDI, SRR, and SRI imaging of the LV as well as assessment of disease characteristics. Despite findings within the normal range on routine standard 2-dimensional echocardiography, SLE was associated with significantly impaired systolic and diastolic myocardial velocities of the LV measured by TDI [mean global TDI: systolic (s): 2.9 +/- 0.9 vs 3.9 +/- 0.7 cm/s, p < 0.05; early (e): 4.3 +/- 1.5 vs 6.3 +/- 1.3 cm/s, p < 0.05; late (a): 2.9 +/- 0.8 vs 3.4 +/- 0.8 cm/s, p < 0.05; values +/- SD); SRR (s: -0.8 +/- 0.1 vs -1.1 +/- 0.1 s(-1); e: 1.1 +/- 0.2 vs 1.6 +/- 0.3 s(-1); a: 0.7 +/- 0.1 vs 1.0 +/- 0.2 s(-1); all p < 0.05); and SR (-15.11 +/- 2.2% vs -19.7 +/- 1.9%; p < 0.05) compared to the control group. Further, elevated disease activity, measured with the ECLAM and the SLEDAI score, resulted in significantly lower values for LV longitudinal function measured by SRR and SR, but not by TDI. SLE is associated with a significant impairment of systolic and diastolic LV longitudinal function in patients without cardiac symptoms. New imaging modalities provide earlier insight into cardiovascular involvement in SLE and seem to be superior to standard echocardiography to detect subclinical myocardial disease.

Spatiotemporal Segmentation and Modeling of the Mitral Valve in Real-Time 3D Echocardiographic Images.

Science.gov (United States)

Pouch, Alison M; Aly, Ahmed H; Lai, Eric K; Yushkevich, Natalie; Stoffers, Rutger H; Gorman, Joseph H; Cheung, Albert T; Gorman, Joseph H; Gorman, Robert C; Yushkevich, Paul A

2017-09-01

Transesophageal echocardiography is the primary imaging modality for preoperative assessment of mitral valves with ischemic mitral regurgitation (IMR). While there are well known echocardiographic insights into the 3D morphology of mitral valves with IMR, such as annular dilation and leaflet tethering, less is understood about how quantification of valve dynamics can inform surgical treatment of IMR or predict short-term recurrence of the disease. As a step towards filling this knowledge gap, we present a novel framework for 4D segmentation and geometric modeling of the mitral valve in real-time 3D echocardiography (rt-3DE). The framework integrates multi-atlas label fusion and template-based medial modeling to generate quantitatively descriptive models of valve dynamics. The novelty of this work is that temporal consistency in the rt-3DE segmentations is enforced during both the segmentation and modeling stages with the use of groupwise label fusion and Kalman filtering. The algorithm is evaluated on rt-3DE data series from 10 patients: five with normal mitral valve morphology and five with severe IMR. In these 10 data series that total 207 individual 3DE images, each 3DE segmentation is validated against manual tracing and temporal consistency between segmentations is demonstrated. The ultimate goal is to generate accurate and consistent representations of valve dynamics that can both visually and quantitatively provide insight into normal and pathological valve function.

Echocardiographic evaluation of thalassemia intermedia patients in Duhok, Iraq.

Science.gov (United States)

Mohammad, Ameen Mosa

2014-12-11

Cardiac complications are among the most serious problems of thalassemia intermedia patients. The current study was initiated to address the latter issue through the study of the echocardiographic findings and correlate it with clinical characteristics of thalassemia intermedia patients in Duhok, Kurdistan region, Iraq. An echocardiographic assessment of 61 beta-thalassemia intermedia cases was performed. It included 30 males and 31 females, with a mean age 19.6 ± 7.5 years. The standard echostudy of two-dimension and M-mode measurements of cardiac chambers were done. The continuous doppler regurgitant jet of tricuspid and pulmonary valves were recorded. Left ventricle diastolic function was assessed by pulsed doppler of mitral valve inflow. To correlate the clinical with echocardiographic findings, patients were divided, according to tricuspid regurgitant velocity, into three groups (intermedia patients. Therapeutic trails targeting these complications are indicated, and echocardiographic assessment is necessary to be offered early for thalassemia intermedia.

Global Longitudinal Strain Is a Superior Predictor of All-Cause Mortality in Heart Failure With Reduced Ejection Fraction

DEFF Research Database (Denmark)

Sengeløv, Morten; Jørgensen, Peter Godsk; Jensen, Jan Skov

2015-01-01

failure clinic. The echocardiographic images were analyzed, and conventional and novel echocardiographic parameters were obtained. RESULTS: Many of the conventional echocardiographic parameters proved to be predictors of mortality. However, GLS remained an independent predictor of mortality...

Echocardiographic diagnosis of rare pathological patterns of sinus of Valsalva aneurysm.

Directory of Open Access Journals (Sweden)

Yali Yang

Full Text Available To evaluate the value and improve the diagnostic accuracy of echocardiography in the diagnosis of a sinus of Valsalva aneurysm (SVA with rare pathological patterns.Echocardiographic features and surgical findings from 270 Chinese patients with SVA treated in the last 18 years (1995-2013 at the Union Hospital were compared retrospectively; 22 of 270 cases had rare patterns.The patients with SVA, a rare origin, a rare extending position, or a rare course accounted for 3.4%, 7.4%, and 0.4% of the 270 cases, respectively. The three most common aneurysmal complications of the patients with rare patterns were severe aortic regurgitation (16, obstruction of the ventricular outflow tract or valvular orifice (3, and conduction disturbance (3. The origin, course, extending position and rupture status of the SVAs determined by echocardiography were entirely consistent with surgical findings in 81.8% of the 22 cases. With the exception of one failed diagnosis of an aneurysmal wall dissection and one misdiagnosis of a descending aortic dissection, the echocardiographic results of SVA complications and associated cardiovascular lesions were also confirmed.We could accurately diagnose SVAs with rare pathological patterns by echocardiographic identification of distinguishing features. However, for several conditions, we could not accurately identify the origin or course of the aneurysm or define its relationship to adjacent structures using conventional echocardiography alone. Therefore, we recommend combining conventional echocardiography with different imaging techniques, such as transesophageal echocardiography, three-dimensional echocardiography, computed tomography angiography, and aortic angiography.

Effects of sedation on echocardiographic variables of left atrial and left ventricular function in healthy cats.

Science.gov (United States)

Ward, Jessica L; Schober, Karsten E; Fuentes, Virginia Luis; Bonagura, John D

2012-10-01

Although sedation is frequently used to facilitate patient compliance in feline echocardiography, the effects of sedative drugs on echocardiographic variables have been poorly documented. This study investigated the effects of two sedation protocols on echocardiographic indices in healthy cats, with special emphasis on the assessment of left atrial size and function, as well as left ventricular diastolic performance. Seven cats underwent echocardiography (transthoracic two-dimensional, spectral Doppler, color flow Doppler and tissue Doppler imaging) before and after sedation with both acepromazine (0.1 mg/kg IM) and butorphanol (0.25 mg/kg IM), or acepromazine (0.1 mg/kg IM), butorphanol (0.25 mg/kg IM) and ketamine (1.5 mg/kg IV). Heart rate increased significantly following acepromazine/butorphanol/ketamine (mean±SD of increase, 40±26 beats/min) and non-invasive systolic blood pressure decreased significantly following acepromazine/butorphanol (mean±SD of decrease, 12±19 mmHg). The majority of echocardiographic variables were not significantly different after sedation compared with baseline values. Both sedation protocols resulted in mildly decreased left ventricular end-diastolic dimension and mildly increased left ventricular end-diastolic wall thickness. This study therefore failed to demonstrate clinically meaningful effects of these sedation protocols on echocardiographic measurements, suggesting that sedation with acepromazine, butorphanol and/or ketamine can be used to facilitate echocardiography in healthy cats.

Echocardiographic versus histologic findings in Marfan syndrome.

Science.gov (United States)

Gu, Xiaoyan; He, Yihua; Li, Zhian; Han, Jiancheng; Chen, Jian; Nixon, J V Ian

2015-02-01

This retrospective study attempted to establish the prevalence of multiple-valve involvement in Marfan syndrome and to compare echocardiographic with histopathologic findings in Marfan patients undergoing valvular or aortic surgery. We reviewed echocardiograms of 73 Marfan patients who underwent cardiovascular surgery from January 2004 through October 2009. Tissue histology was available for comparison in 29 patients. Among the 73 patients, 66 underwent aortic valve replacement or the Bentall procedure. Histologic findings were available in 29 patients, all of whom had myxomatous degeneration. Of 63 patients with moderate or severe aortic regurgitation as determined by echocardiography, 4 had thickened aortic valves. The echocardiographic findings in 18 patients with mitral involvement included mitral prolapse in 15. Of 11 patients with moderate or severe mitral regurgitation as determined by echocardiography, 4 underwent mitral valve repair and 7 mitral valve replacement. Histologic findings among mitral valve replacement patients showed thickened valve tissue and myxomatous degeneration. Tricuspid involvement was seen echocardiographically in 8 patients, all of whom had tricuspid prolapse. Two patients had severe tricuspid regurgitation, and both underwent repair. Both mitral and tricuspid involvement were seen echocardiographically in 7 patients. Among the 73 patients undergoing cardiac surgery for Marfan syndrome, 66 had moderate or severe aortic regurgitation, although their valves manifested few histologic changes. Eighteen patients had mitral involvement (moderate or severe mitral regurgitation, prolapse, or both), and 8 had tricuspid involvement. Mitral valves were most frequently found to have histologic changes, but the tricuspid valve was invariably involved.

Cardiac biplane strain imaging: initial in vivo experience

Energy Technology Data Exchange (ETDEWEB)

Lopata, R G P; Nillesen, M M; Thijssen, J M; De Korte, C L [Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Verrijp, C N; Lammens, M M Y; Van der Laak, J A W M [Department of Pathology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Singh, S K; Van Wetten, H B [Department of Cardiothoracic Surgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kapusta, L [Pediatric Cardiology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)], E-mail: R.Lopata@cukz.umcn.nl

2010-02-21

In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (<100 Hz) using a commercial platform with an RF interface. For testing the method in vivo, biplane image sequences of the heart were recorded during the cardiac cycle in four dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve ({delta}p: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy ({delta}p = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

Cardiac biplane strain imaging: initial in vivo experience

International Nuclear Information System (INIS)

Lopata, R G P; Nillesen, M M; Thijssen, J M; De Korte, C L; Verrijp, C N; Lammens, M M Y; Van der Laak, J A W M; Singh, S K; Van Wetten, H B; Kapusta, L

2010-01-01

In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (<100 Hz) using a commercial platform with an RF interface. For testing the method in vivo, biplane image sequences of the heart were recorded during the cardiac cycle in four dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve (Δp: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy (Δp = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

Added clinical value of applying myocardial deformation imaging to assess right ventricular function.

Science.gov (United States)

Sokalskis, Vladislavs; Peluso, Diletta; Jagodzinski, Annika; Sinning, Christoph

2017-06-01

Right heart dysfunction has been found to be a strong prognostic factor predicting adverse outcome in various cardiopulmonary diseases. Conventional echocardiographic measurements can be limited by geometrical assumptions and impaired reproducibility. Speckle tracking-derived strain provides a robust quantification of right ventricular function. It explicitly evaluates myocardial deformation, as opposed to tissue Doppler-derived strain, which is computed from tissue velocity gradients. Right ventricular longitudinal strain provides a sensitive tool for detecting right ventricular dysfunction, even at subclinical levels. Moreover, the longitudinal strain can be applied for prognostic stratification of patients with pulmonary hypertension, pulmonary embolism, and congestive heart failure. Speckle tracking-derived right atrial strain, right ventricular longitudinal strain-derived mechanical dyssynchrony, and three-dimensional echocardiography-derived strain are emerging imaging parameters and methods. Their application in research is paving the way for their clinical use. © 2017, Wiley Periodicals, Inc.

State-of-the-Art Review of Echocardiographic Imaging in the Evaluation and Treatment of Functional Tricuspid Regurgitation.

Science.gov (United States)

Hahn, Rebecca T

2016-12-01

Functional or secondary tricuspid regurgitation (TR) is the most common cause of severe TR in the Western world. The presence of functional TR, either isolated or in combination with left heart disease, is associated with unfavorable natural history. Surgical mortality for isolated tricuspid valve interventions remains higher than for any other single valve surgery, and surgical options for repair do not have consistent long-term durability. In addition, as more patients undergo transcatheter left valve interventions, developing transcatheter solutions for functional TR has gained greater momentum. Numerous transcatheter devices are currently in early clinical trials. All patients require an assessment of valve morphology and function, and transcatheter devices typically require intraprocedural guidance by echocardiography. The following review will describe tricuspid anatomy, define echocardiographic views for evaluating tricuspid valve morphology and function, and discuss imaging requirements for the current transcatheter devices under development for the treatment of functional TR. © 2016 American Heart Association, Inc.

OSM-Classic : An optical imaging technique for accurately determining strain

Science.gov (United States)

Aldrich, Daniel R.; Ayranci, Cagri; Nobes, David S.

OSM-Classic is a program designed in MATLAB® to provide a method of accurately determining strain in a test sample using an optical imaging technique. Measuring strain for the mechanical characterization of materials is most commonly performed with extensometers, LVDT (linear variable differential transistors), and strain gauges; however, these strain measurement methods suffer from their fragile nature and it is not particularly easy to attach these devices to the material for testing. To alleviate these potential problems, an optical approach that does not require contact with the specimen can be implemented to measure the strain. OSM-Classic is a software that interrogates a series of images to determine elongation in a test sample and hence, strain of the specimen. It was designed to provide a graphical user interface that includes image processing with a dynamic region of interest. Additionally, the stain is calculated directly while providing active feedback during the processing.

Interatrial septum pacing decreases atrial dyssynchrony on strain rate imaging compared with right atrial appendage pacing.

Science.gov (United States)

Yasuoka, Yoshinori; Abe, Haruhiko; Umekawa, Seiko; Katsuki, Keiko; Tanaka, Norio; Araki, Ryo; Imanaka, Takahiro; Matsutera, Ryo; Morisawa, Daisuke; Kitada, Hirokazu; Hattori, Susumu; Noda, Yoshiki; Adachi, Hidenori; Sasaki, Tatsuya; Miyatake, Kunio

2011-03-01

Interatrial septum pacing (IAS-P) decreases atrial conduction delay compared with right atrial appendage pacing (RAA-P). We evaluate the atrial contraction with strain rate of tissue Doppler imaging (TDI) during sinus activation or with IAS-P or RAA-P. Fifty-two patients with permanent pacemaker for sinus node disease were enrolled in the study. Twenty-three subjects were with IAS-P and 29 with RAA-P. The time from end-diastole to peak end-diastolic strain rate was measured and corrected with RR interval on electrocardiogram. It was defined as the time from end-diastole to peak end-diastolic strain rate (TSRc), and the balance between maximum and minimum TSRc at three sites (ΔTSRc) was compared during sinus activation and with pacing rhythm in each group. There were no significant differences observed in general characteristics and standard echocardiographic parameters except the duration of pacing P wave between the two groups. The duration was significantly shorter in the IAS-P group compared with the RAA-P group (95 ± 34 vs 138 ± 41; P = 0.001). TSRc was significantly different between sinus activation and pacing rhythm (36.3 ± 35.7 vs 61.6 ± 36.3; P = 0.003) in the RAA-P group, whereas no significant differences were observed in the IAS-P group (25.4 ± 12.1 vs 27.7 ± 14.7; NS). During the follow-up (mean 2.4 ± 0.7 years), the incidence of paroxysmal atrial fibrillation (AF) conversion to permanent AF was not significantly different between the two groups. IAS-P decreased the contraction delay on atrial TDI compared to RAA-P; however, it did not contribute to the reduction of AF incidence in the present study. ©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.

Abnormal maternal echocardiographic findings in triplet pregnancies presenting with dyspnoea.

Science.gov (United States)

Elhenicky, Marie; Distelmaier, Klaus; Mailath-Pokorny, Mariella; Worda, Christof; Langer, Martin; Worda, Katharina

2016-03-01

The objective of our study was to evaluate the prevalence of abnormal maternal echocardiographic findings in triplet pregnancies presenting with dyspnoea. Between 2003 and 2013, patients' records of 96 triplet pregnancies at our department were analysed including maternal and fetal outcome, echocardiographic parameters and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. After exclusion of triplet pregnancies with fetal demise before 23 + 0 weeks, selective feticide or missing outcome data, the study population consisted of 60 triplet pregnancies. All women with dyspnoea underwent echocardiography and measurement of NT-proBNP. Dyspnoea towards the end of pregnancy was observed in 13.3% (8/60) of all women with triplet pregnancies, and all of these women underwent echocardiography. The prevalence of abnormal echocardiographic findings in women with dyspnoea was 37.5% (3/8) with peripartum cardiomyopathy in one woman. Median serum NT-proBNP was significantly higher in women with abnormal echocardiographic findings compared with those without (1779 ng/ml, range 1045-6076 ng/ml vs 172 ng/ml, range 50-311 ng/ml; p presenting with dyspnoea show a high prevalence of abnormal echocardiographic findings. Since dyspnoea is a common sign in triplet pregnancies and is associated with a high rate of cardiac involvement, echocardiography and evaluation of maternal NT-proBNP could be considered to improve early diagnosis and perinatal management.

Cardiac biplane strain imaging: initial in vivo experience

Science.gov (United States)

Lopata, R. G. P.; Nillesen, M. M.; Verrijp, C. N.; Singh, S. K.; Lammens, M. M. Y.; van der Laak, J. A. W. M.; van Wetten, H. B.; Thijssen, J. M.; Kapusta, L.; de Korte, C. L.

2010-02-01

In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to test the method in vivo. The proposed approach can serve as a framework to monitor the development of cardiac hypertrophy and fibrosis. A 2D strain estimation technique using radio frequency (RF) ultrasound data was applied. Biplane image acquisition was performed at a relatively low frame rate (dogs with an aortic stenosis. Initial results reveal the feasibility of measuring large radial, circumferential and longitudinal cumulative strain (up to 70%) at a frame rate of 100 Hz. Mean radial strain curves of a manually segmented region-of-interest in the infero-lateral wall show excellent correlation between the measured strain curves acquired in two perpendicular planes. Furthermore, the results show the feasibility and reproducibility of assessing radial, circumferential and longitudinal strains simultaneously. In this preliminary study, three beagles developed an elevated pressure gradient over the aortic valve (Δp: 100-200 mmHg) and myocardial hypertrophy. One dog did not develop any sign of hypertrophy (Δp = 20 mmHg). Initial strain (rate) results showed that the maximum strain (rate) decreased with increasing valvular stenosis (-50%), which is in accordance with previous studies. Histological findings corroborated these results and showed an increase in fibrotic tissue for the hearts with larger pressure gradients (100, 200 mmHg), as well as lower strain and strain rate values.

Performance Analysis and Experimental Validation of the Direct Strain Imaging Method

Science.gov (United States)

Athanasios Iliopoulos; John G. Michopoulos; John C. Hermanson

2013-01-01

Direct Strain Imaging accomplishes full field measurement of the strain tensor on the surface of a deforming body, by utilizing arbitrarily oriented engineering strain measurements originating from digital imaging. In this paper an evaluation of the method’s performance with respect to its operating parameter space is presented along with a preliminary...

X-ray strain tensor imaging: FEM simulation and experiments with a micro-CT.

Science.gov (United States)

Kim, Jae G; Park, So E; Lee, Soo Y

2014-01-01

In tissue elasticity imaging, measuring the strain tensor components is necessary to solve the inverse problem. However, it is impractical to measure all the tensor components in ultrasound or MRI elastography because of their anisotropic spatial resolution. The objective of this study is to compute 3D strain tensor maps from the 3D CT images of a tissue-mimicking phantom. We took 3D micro-CT images of the phantom twice with applying two different mechanical compressions to it. Applying the 3D image correlation technique to the CT images under different compression, we computed 3D displacement vectors and strain tensors at every pixel. To evaluate the accuracy of the strain tensor maps, we made a 3D FEM model of the phantom, and we computed strain tensor maps through FEM simulation. Experimentally obtained strain tensor maps showed similar patterns to the FEM-simulated ones in visual inspection. The correlation between the strain tensor maps obtained from the experiment and the FEM simulation ranges from 0.03 to 0.93. Even though the strain tensor maps suffer from high level noise, we expect the x-ray strain tensor imaging may find some biomedical applications such as malignant tissue characterization and stress analysis inside the tissues.

Clinical and Echocardiographic Evaluation of Regional Systolic Function Detected by Tissue Doppler Imaging in Hypertrophic Cardiomyopathy

Directory of Open Access Journals (Sweden)

A Sadeghpour

2009-09-01

Full Text Available Background: Hypertrophic cardiomyopathy (HCM is the most common type of the genetic cardiovasculardiseases. Regarding to tremendous heterogeneity in the phenotypic expression of HCM, which is generally unrelatedto genotype, we aimed to study, clinical and echocardiographic parameters such as Tissue Doppler Imaging(TDI in various subtypes of HCM patients and evaluate the influence of race and gender in Iranian patients.Methods: Patients with HCM underwent a complete clinical and echocardiographic study including TDI toassess regional systolic contraction( in the 12 segments and early diastolic annular velocity (Em from theseptal mitral annulus.Results: The study comprised 41 patients (20 women, mean age = 41 ± 15 years with mean LVEF 55%±4.8%and mean maximal septal thickness 2.07cm. Considering LVOT gradient>30mmHg, hypertrophic obstructivecardiomyopathy (HOCM was found in 18 (45%. Asymmetric septal hypertrophy (ASH existed in 27 patients(67%, systolic anterior motion of anterior mitral leaflet (SAM in 25 persons (64%. Nineteen patients (46.3%were included in NYHA function class (FC II and 6 (14.7% in FC III or higher. We found syncope in 10(24.4%, chest pain in 4 (9.8%, atrial fibrilation in 14.6 % and ventricular arrhythmias in (17.1% of patients.History of ICD was seen in 7 (17.1% and PPM in 9 cases. Mean E’ velocity was 5.44± 1.65 cm/sec and S velocity5.70± 1.49 cm/sec with significant lower S velocity and E’ in syncope patients. Overall, HOCM patients hadgrade II diastolic dysfunction with E/É >15(17.54±7.46. Majority (25 of cases (61% were categorized in typeIII of HCM. RV involvement was observed in 11 patients (28.2%.No significant differences existed betweenprevalence of syncope and dysrhythmia among HCM and HOCM patients.Conclusion: In our study, we found lower detection of latent HOCM, compared to other studies, suggestive ofinadequate use of appropriate provocative maneuvers such as exercise stress echocardiography and amyl

Cardiac biplane strain imaging: initial in vivo experience.

NARCIS (Netherlands)

Lopata, R.G.P.; Nillesen, M.M.; Verrijp, C.N.; Singh, S.K.; Lammens, M.M.Y.; Laak, J.A.W.M. van der; Wetten, H.B. van; Thijssen, J.M.; Kapusta, L.; Korte, C.L. de

2010-01-01

In this study, first we propose a biplane strain imaging method using a commercial ultrasound system, yielding estimation of the strain in three orthogonal directions. Secondly, an animal model of a child's heart was introduced that is suitable to simulate congenital heart disease and was used to

Left ventricular noncompaction: Clinical-echocardiographic study

Directory of Open Access Journals (Sweden)

Nikolić Aleksandra

2012-01-01

Full Text Available Background/Aim. Left ventricular noncompaction (LVNC is a disorder in endomyocardial morphogenesis, seen either isolated (in the absence of other cardiac anomalies or in association with congenital heart disease and some neuromuscular diseases. Intrauterine arrest of the compaction of myocardial fibers is postulated to be the reason of LVNC. Recognition of this condition is extremely important due to its high mortality and morbidity that lead to progressive heart failure, ventricular arrhythmias and thromboembolic events. The aim of this study was to determine the prevalence and clinical presentation of LVNC among consecutive outpatients according to clinical and echocardiographyic findings. Methode. A total of 3,854 consecutive patients examined at the Institute for Cardiovascular Diseases within a period January 2006 - January 2007 were included in the study. All the patients underwent echocardiographic examination using the same equipment (Vivid 7, GE Medical System. Echocardiographic parameters and clinical presentation in patients with echocardiographic criteria for LVNC were analyzed. Results. Analyzing 3,854 consecutive outpatients, using two-dimensional Color Doppler echocardiography from January 2006 to January 2007, 12 patients met the criteria for LVNC. Seven of them were male. The mean age at diagnosis was 45 ± 15 years. Analyzing clinical manifestation of LVNC it was found that seven patients had signs of heart failure, six had arrhythmias with no embolic events. Conclusion. Our results suggest that the real prevalence of LVNC may be higher than expected. New studies have to be done to solve this problem.

An echocardiographic study of healthy Border Collies with normal reference ranges for the breed.

Science.gov (United States)

Jacobson, Jake H; Boon, June A; Bright, Janice M

2013-06-01

The objectives of this study were to obtain standard echocardiographic measurements from healthy Border Collies and to compare these measurements to those previously reported for a general population of dogs. Standard echocardiographic data were obtained from twenty apparently healthy Border Collie dogs. These data (n = 20) were compared to data obtained from a general population of healthy dogs (n = 69). Border Collies were deemed healthy based on normal history, physical examination, complete blood count, serum biochemical profile, electrocardiogram, and blood pressure, with no evidence of congenital or acquired heart disease on echocardiographic examination. Standard two dimensional, M-mode, and Doppler echocardiographic measurements were obtained and normal ranges determined. The data were compared to data previously obtained at our hospital from a general population of normal dogs. Two dimensional, M-mode, and Doppler reference ranges for healthy Border Collies are presented in tabular form. Comparison of the weight adjusted M-mode echocardiographic means from Border Collies to those from the general population of dogs showed Border Collies to have larger left ventricular systolic and diastolic dimensions, smaller interventricular septal thickness, and lower fractional shortening. There are differences in some echocardiographic parameters between healthy Border Collies and the general dog population, and the echocardiographic reference ranges provided in this study should be used as breed specific reference values for Border Collies. Copyright © 2013 Elsevier B.V. All rights reserved.

Assessment of strain and strain rate by two-dimensional speckle tracking in mice: comparison with tissue Doppler echocardiography and conductance catheter measurements.

Science.gov (United States)

Ferferieva, V; Van den Bergh, A; Claus, P; Jasaityte, R; La Gerche, A; Rademakers, F; Herijgers, P; D'hooge, J

2013-08-01

This study was designed in order to compare the strain and strain rate deformation parameters assessed by speckle tracking imaging (STI) with those of tissue Doppler imaging (TDI) and conductance catheter measurements in chronic murine models of left ventricular (LV) dysfunction. Twenty-four male C57BL/6J mice were assigned to wild-type (n = 8), myocardial infarction (n = 8) and transaortic constriction (n = 8) groups. Echocardiographic and conductance measurements were simultaneously performed at rest and during dobutamine infusion (5 µg/kg/min) in all animals 10 weeks post-surgery. The LV circumferential strain (Scirc) and the strain rate (SRcirc) were derived from grey scale and tissue Doppler data at frame rates of 224 and 375 Hz, respectively. Scirc and SRcirc by TDI/STI correlated well with the preload recruitable stroke work (PRSW) (r = -0.64 and -0.71 for TDI; r = -0.46 and -0.50 for STI, P < 0.05). Both modalities showed a good agreement with respect to Scirc and SRcirc (r = 0.60 and r = 0.63, P < 0.05). During stress, however, TDI-estimated Scirc and SRcirc values were predominantly higher than those measured by STI (P < 0.05). The similarity of Scirc and SRcirc measurements with respect to the STI/TDI data was examined by the Bland-Altman analysis. In mice, the STI- and TDI-derived strain and strain rate deformation parameters relate closely to intrinsic myocardial function. At low heart rate-to-frame rate ratios (HR/FR), both STI and TDI are equally acceptable for assessing the LV function non-invasively in these animals. At HR/FR (e.g. dobutamine challenge), however, these methods cannot be used interchangeably as STI underestimates S and SR at high values.

An Echocardiographic Study of Left Ventricular Size and Cardiac Function in Adolescent Females with Anorexia Nervosa.

Science.gov (United States)

Escudero, Carolina A; Potts, James E; Lam, Pei-Yoong; De Souza, Astrid M; Mugford, Gerald J; Sandor, George G S

2016-01-01

This retrospective case-control study investigated cardiac dimensions and ventricular function in female adolescents with anorexia nervosa (AN) compared with controls. Echocardiographic measurements of left ventricular (LV) dimensions, LV mass index, left atrial size and cardiac index were made. Detailed measures of systolic and diastolic ventricular function were made including tissue Doppler imaging. Patients were stratified by body mass index ≤10th percentile (AN ≤ 10th) and >10th percentile (AN > 10th). Ninety-five AN patients and 58 controls were included. AN and AN ≤ 10th groups had reduced LV dimensions, LV mass index, left atrial size and cardiac index compared with controls. There were no differences between groups in measures of systolic function. Measures of diastolic tissue Doppler imaging were decreased in AN and AN ≤ 10th. No differences in echocardiographic measurements existed between controls and AN > 10th. Female adolescents with AN have preserved systolic function and abnormalities of diastolic ventricular function. AN ≤ 10th may be a higher risk group. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.

Three-dimensional ultrasound strain imaging of skeletal muscles

NARCIS (Netherlands)

Gijsbertse, Kaj; Sprengers, Andre M.; Nillesen, Maartje; Hansen, Hendrik H.G.; Verdonschot, Nico; De Korte, Chris L.

2015-01-01

Muscle contraction is characterized by large deformation and translation, which requires a multi-dimensional imaging modality to reveal its behavior. Previous work on ultrasound strain imaging of the muscle contraction was limited to 2D and bi-plane techniques. In this study, a three-dimensional

Right ventricular strain in heart failure: Clinical perspective.

Science.gov (United States)

Tadic, Marijana; Pieske-Kraigher, Elisabeth; Cuspidi, Cesare; Morris, Daniel A; Burkhardt, Franziska; Baudisch, Ana; Haßfeld, Sabine; Tschöpe, Carsten; Pieske, Burket

2017-10-01

The number of studies demonstrating the importance of right ventricular remodelling in a wide range of cardiovascular diseases has increased in the past two decades. Speckle-tracking imaging provides new variables that give comprehensive information about right ventricular function and mechanics. In this review, we summarize current knowledge of right ventricular mechanics in heart failure with reduced ejection fraction and preserved ejection fraction. We searched PubMed, MEDLINE, Ovid and Embase databases for studies published from January 2000 to December 2016 in the English language using the following keywords: "right ventricle"; "strain"; "speckle tracking"; "heart failure with reduced ejection fraction"; and "heart failure with preserved ejection fraction". Investigations showed that right ventricular dysfunction is associated with higher cardiovascular and overall mortality in patients with heart failure, irrespective of ejection fraction. The number of studies investigating right ventricular strain in patients with heart failure with reduced ejection fraction is constantly increasing, whereas data on right ventricular mechanics in patients with heart failure with preserved ejection fraction are limited. Given the high feasibility, accuracy and clinical implications of right ventricular strain in the population with heart failure, it is of great importance to try to include the evaluation of right ventricular strain as a regular part of each echocardiographic examination in patients with heart failure. However, further investigations are necessary to establish right ventricular strain as a standard variable for decision-making. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Echocardiographic evaluation during weaning from mechanical ventilation

Directory of Open Access Journals (Sweden)

Luciele Medianeira Schifelbain

2011-01-01

Full Text Available INTRODUCTION: Echocardiographic, electrocardiographic and other cardiorespiratory variables can change during weaning from mechanical ventilation. OBJECTIVES: To analyze changes in cardiac function, using Doppler echocardiogram, in critical patients during weaning from mechanical ventilation, using two different weaning methods: pressure support ventilation and T-tube; and comparing patient subgroups: success vs. failure in weaning. METHODS: Randomized crossover clinical trial including patients under mechanical ventilation for more than 48 h and considered ready for weaning. Cardiorespiratory variables, oxygenation, electrocardiogram and Doppler echocardiogram findings were analyzed at baseline and after 30 min in pressure support ventilation and T-tube. Pressure support ventilation vs. T-tube and weaning success vs. failure were compared using ANOVA and Student's t-test. The level of significance was p<0.05. RESULTS: Twenty-four adult patients were evaluated. Seven patients failed at the first weaning attempt. No echocardiographic or electrocardiographic differences were observed between pressure support ventilation and T-tube. Weaning failure patients presented increases in left atrium, intraventricular septum thickness, posterior wall thickness and diameter of left ventricle and shorter isovolumetric relaxation time. Successfully weaned patients had higher levels of oxygenation. CONCLUSION: No differences were observed between Doppler echocardiographic variables and electrocardiographic and other cardiorespiratory variables during pressure support ventilation and T-tube. However cardiac structures were smaller, isovolumetric relaxation time was larger, and oxygenation level was greater in successfully weaned patients

Large area strain analysis using scanning transmission electron microscopy across multiple images

International Nuclear Information System (INIS)

Oni, A. A.; Sang, X.; LeBeau, J. M.; Raju, S. V.; Saxena, S.; Dumpala, S.; Broderick, S.; Rajan, K.; Kumar, A.; Sinnott, S.

2015-01-01

Here, we apply revolving scanning transmission electron microscopy to measure lattice strain across a sample using a single reference area. To do so, we remove image distortion introduced by sample drift, which usually restricts strain analysis to a single image. Overcoming this challenge, we show that it is possible to use strain reference areas elsewhere in the sample, thereby enabling reliable strain mapping across large areas. As a prototypical example, we determine the strain present within the microstructure of a Ni-based superalloy directly from atom column positions as well as geometric phase analysis. While maintaining atomic resolution, we quantify strain within nanoscale regions and demonstrate that large, unit-cell level strain fluctuations are present within the intermetallic phase

Association Between Echocardiography Laboratory Accreditation and the Quality of Imaging and Reporting for Valvular Heart Disease.

Science.gov (United States)

Thaden, Jeremy J; Tsang, Michael Y; Ayoub, Chadi; Padang, Ratnasari; Nkomo, Vuyisile T; Tucker, Stephen F; Cassidy, Cynthia S; Bremer, Merri; Kane, Garvan C; Pellikka, Patricia A

2017-08-01

It is presumed that echocardiographic laboratory accreditation leads to improved quality, but there are few data. We sought to compare the quality of echocardiographic examinations performed at accredited versus nonaccredited laboratories for the evaluation of valvular heart disease. We enrolled 335 consecutive valvular heart disease subjects who underwent echocardiography at our institution and an external accredited or nonaccredited institution within 6 months. Completeness and quality of echocardiographic reports and images were assessed by investigators blinded to the external laboratory accreditation status and echocardiographic results. Compared with nonaccredited laboratories, accredited sites more frequently reported patient sex (94% versus 78%; P heart disease. Future quality improvement initiatives should highlight the importance of high-quality color Doppler imaging and echocardiographic quantification to improve the accuracy, reproducibility, and quality of echocardiographic studies for valvular heart disease. © 2017 American Heart Association, Inc.

Clinical Electrocardiographic and Echocardiographic Features of ...

African Journals Online (AJOL)

Clinical Electrocardiographic and Echocardiographic Features of Atrial Fibrillation in Nigerians: An Analysis of 39 Patients Seen at the Lagos University Teaching Hospital. ... Congestive cardiac failure was present in 74% of the subjects with a mean NYHA class of about III. Embolic phenomenon was observed in 15% of the ...

Echocardiographic and radiographic findings in a cohort of healthy adult green iguanas (Iguana iguana).

Science.gov (United States)

Gustavsen, Kate A; Saunders, Ashley B; Young, Benjamin D; Winter, Randolph L; Hoppes, Sharman M

2014-09-01

To describe characteristics of echocardiography and cranial coelomic radiography in a cohort of iguanas. Twenty apparently healthy adult green iguanas (Iguana iguana) from a reptile sanctuary. Physical examination, radiography, two-dimensional and color Doppler echocardiography were performed to assess cardiac structures and function, and any related normal or abnormal findings were recorded. Echocardiographic examination was possible without sedation and allowed visualization of the great vessels, atria, and ventricle. Some structures could not be evaluated in a minority of the iguanas due to individual differences in bony conformation and imaging quality. Suspected abnormal echocardiographic findings in 3 iguanas included pericardial effusion (n = 1) and enlarged caudal vena cava and/or sinus venosus (n = 2). Objective measurements were repeatable as assessed by within-subject coefficient of variation, and reliable as assessed by intra-observer intraclass correlation coefficient. Left atrial and ventricular measurements were significantly correlated with body weight. Valve regurgitation was common, with atrioventricular valve regurgitation present in 53% (9/17) and aortic or pulmonic valve regurgitation in 71% (12/17) of otherwise normal iguanas. A heart murmur was not appreciated during examination of any of the iguanas. Heart size cannot be measured radiographically due to superimposition and silhouetting of other coelomic structures. Echocardiographic or radiographic findings consistent with mineralization of the great vessels were present in 76% of iguanas (13/17). Echocardiography in iguanas is well tolerated without sedation and allowed both subjective evaluation and structural measurements. Valve regurgitation and great vessel mineralization were commonly observed in this cohort of apparently healthy adult iguanas. Copyright © 2014 Elsevier B.V. All rights reserved.

Echocardiographic Evaluation of Tricuspid Prosthetic Valves: An Update

Directory of Open Access Journals (Sweden)

Dimitrios Maragiannis, MD, FASE, FACC

2016-05-01

Full Text Available This review focuses on the diagnostic value of novel echocardiographic techniques and the clinical application of recently described algorithms to assess tricuspid prosthetic valve function.

A comparison between brachial and echocardiographic systolic time intervals.

Directory of Open Access Journals (Sweden)

Ho-Ming Su

Full Text Available Systolic time interval (STI is an established noninvasive technique for the assessment of cardiac function. Brachial STIs can be automatically determined by an ankle-brachial index (ABI-form device. The aims of this study are to evaluate whether the STIs measured from ABI-form device can represent those measured from echocardiography and to compare the diagnostic values of brachial and echocardiographic STIs in the prediction of left ventricular ejection fraction (LVEF <50%. A total of 849 patients were included in the study. Brachial pre-ejection period (bPEP and brachial ejection time (bET were measured using an ABI-form device and pre-ejection period (PEP and ejection time (ET were measured from echocardiography. Agreement was assessed by correlation coefficient and Bland-Altman plot. Brachial STIs had a significant correlation with echocardiographic STIs (r = 0.644, P<0.001 for bPEP and PEP; r  = 0.850, P<0.001 for bET and ET; r = 0.708, P<0.001 for bPEP/bET and PEP/ET. The disagreement between brachial and echocardiographic STIs (brachial STIs minus echocardiographic STIs was 28.55 ms for bPEP and PEP, -4.15 ms for bET and ET and -0.11 for bPEP/bET and PEP/ET. The areas under the curve for bPEP/bET and PEP/ET in the prediction of LVEF <50% were 0.771 and 0.765, respectively. Brachial STIs were good alternatives to STIs obtained from echocardiography and also helpful in prediction of LVEF <50%. Brachial STIs automatically obtained from an ABI-form device may be helpful for evaluation of left ventricular systolic dysfunction.

Common echocardiographic abnormalities in Nigerians of different ...

African Journals Online (AJOL)

2012-09-17

Sep 17, 2012 ... artery disease, cardiac murmurs, atrial fibrillation, stroke, and transient ischaemic attack.[4,5] In some circumstances, the examination is an appropriate screening test even in the absence of cardiovascular symptoms, especially. Common echocardiographic abnormalities in. Nigerians of different age groups.

Transesophageal echocardiography simulation is an effective tool in teaching psychomotor skills to novice echocardiographers.

Science.gov (United States)

Sohmer, Benjamin; Hudson, Christopher; Hudson, Jordan; Posner, Glenn D; Naik, Viren

2014-03-01

Performance of transesophageal echocardiography (TEE) requires the psychomotor ability to obtain interpretable echocardiographic images. The purpose of this study was to determine the effectiveness of a simulation-based curriculum in which a TEE simulator is used to teach the psychomotor skills to novice echocardiographers and to compare instructor-guided with self-directed online delivery of the curriculum. After institutional review board approval, subjects inexperienced in TEE completed an online review of TEE material prior to a baseline pre-test of TEE psychomotor skills using the simulator. Subjects were randomized to two groups. The first group received an instructor-guided lesson of TEE psychomotor skills with the simulator. The second group received a self-directed slide presentation of TEE psychomotor skills with the simulator. Both lessons delivered identical information. Following their respective training sessions, all subjects performed a post-test of their TEE psychomotor skills using the simulator. Two assessors rated the TEE performances using a validated scoring system for acquisition of images. Pre-test TEE simulator scores were similar between the two instruction groups (9.0 vs 5.0; P = 0.28). The scores in both groups improved significantly following training, regardless of the method of instruction (P psychomotor skills. There was no difference in improvement between the different modalities of instruction. Further research will examine the need for a faculty resource for a curriculum in which a simulator is used as an adjunct.

Echocardiographic Assessment of Heart Valve Prostheses

Science.gov (United States)

Sordelli, Chiara; Severino, Sergio; Ascione, Luigi; Coppolino, Pasquale; Caso, Pio

2014-01-01

Patients submitted to valve replacement with mechanical or biological prosthesis, may present symptoms related either to valvular malfunction or ventricular dysfunction from other causes. Because a clinical examination is not sufficient to evaluate a prosthetic valve, several diagnostic methods have been proposed to assess the functional status of a prosthetic valve. This review provides an overview of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. Compared to native valves, echocardiographic evaluation of prosthetic valves is certainly more complex, both for the examination and the interpretation. Echocardiography also allows discriminating between intra- and/or peri-prosthetic regurgitation, present in the majority of mechanical valves. Transthoracic echocardiography (TTE) requires different angles of the probe with unconventional views. Transesophageal echocardiography (TEE) is the method of choice in presence of technical difficulties. Three-dimensional (3D)-TEE seems to be superior to 2D-TEE, especially in the assessment of paravalvular leak regurgitation (PVL) that it provides improved localization and analysis of the PVL size and shape. PMID:28465917

The Peak Pairs algorithm for strain mapping from HRTEM images

Energy Technology Data Exchange (ETDEWEB)

Galindo, Pedro L. [Departamento de Lenguajes y Sistemas Informaticos, CASEM, Universidad de Cadiz, Pol. Rio San Pedro s/n. 11510, Puerto Real, Cadiz (Spain)], E-mail: pedro.galindo@uca.es; Kret, Slawomir [Institute of Physics, PAS, AL. Lotnikow 32/46, 02-668 Warsaw (Poland); Sanchez, Ana M. [Departamento de Ciencia de los Materiales e Ing. Metalurgica y Q. Inorganica, Facultad de Ciencias, Universidad de Cadiz, Pol. Rio San Pedro s/n. 11510, Puerto Real, Cadiz (Spain); Laval, Jean-Yves [Laboratoire de Physique du Solide, UPR5 CNRS-ESPCI, Paris (France); Yanez, Andres; Pizarro, Joaquin; Guerrero, Elisa [Departamento de Lenguajes y Sistemas Informaticos, CASEM, Universidad de Cadiz, Pol. Rio San Pedro s/n. 11510, Puerto Real, Cadiz (Spain); Ben, Teresa; Molina, Sergio I. [Departamento de Ciencia de los Materiales e Ing. Metalurgica y Q. Inorganica, Facultad de Ciencias, Universidad de Cadiz, Pol. Rio San Pedro s/n. 11510, Puerto Real, Cadiz (Spain)

2007-11-15

Strain mapping is defined as a numerical image-processing technique that measures the local shifts of image details around a crystal defect with respect to the ideal, defect-free, positions in the bulk. Algorithms to map elastic strains from high-resolution transmission electron microscopy (HRTEM) images may be classified into two categories: those based on the detection of peaks of intensity in real space and the Geometric Phase approach, calculated in Fourier space. In this paper, we discuss both categories and propose an alternative real space algorithm (Peak Pairs) based on the detection of pairs of intensity maxima in an affine transformed space dependent on the reference area. In spite of the fact that it is a real space approach, the Peak Pairs algorithm exhibits good behaviour at heavily distorted defect cores, e.g. interfaces and dislocations. Quantitative results are reported from experiments to determine local strain in different types of semiconductor heterostructures.

Echocardiographic evaluation of pre-diagnostic development in young relatives genetically predisposed to hypertrophic cardiomyopathy

DEFF Research Database (Denmark)

Jensen, Morten K; Havndrup, Ole; Christiansen, Michael

2015-01-01

Identification of the first echocardiographic manifestations of hypertrophic cardiomyopathy may be important for clinical management and our understanding of the pathogenesis. We studied the development of pre-diagnostic echocardiographic changes in young relatives to HCM patients during long...... of relatives with unknown genetic status. Children carrying pathogenic sarcomere gene mutations develop reduced LVEDd and increased E/e' as first pre-diagnostic echocardiographic manifestations during follow-up into adulthood.......-term years follow-up. HCM-relatives not fulfilling the diagnostic criteria for HCM and age of family screening of 11 sarcomere genes, CRYAB, α-GAL, and titin, we evaluated...

Echocardiographic evaluation of heart valve prosthetic dysfunction

Directory of Open Access Journals (Sweden)

Yuriy Ivaniv

2018-02-01

Full Text Available Patients with replaced heart valve submitted to echocardiographic examination may have symptoms related either to valvular malfunction or ventricular dysfunction from different causes. Clinical examination is not reliable in a prosthetic valve evaluation and the main information regarding its function could be obtained using different cardiac ultrasound modalities. This review provides a description of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. For the interpretation of echocardiography there is a need in special knowledge of prosthesis types and possible reasons of prosthetic function deterioration. Echocardiography allows to reveal valve thrombosis, pannus formation, vegetation and such complications of infective endocarditis as valve ring abscess or dehiscence. Transthoracic echocardiography requires different section plane angles and unconventional views. Transesophageal echocardiography is more often used than in native valve examination due to better visualization of prosthetic valve structure and function. Three-dimensional echocardiography could provide more detailed visual information especially in the assessment of paravalvular regurgitation or valve obstruction.

Comparison of left ventricular function assessment between echocardiography and MRI in Duchenne muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Buddhe, Sujatha; Lewin, Mark; Olson, Aaron; Soriano, Brian D. [University of Washington School of Medicine and Seattle Children' s Hospital, Division of Cardiology, Department of Pediatrics, Seattle, WA (United States); Ferguson, Mark [University of Washington School of Medicine and Seattle Children' s Hospital, Department of Radiology, Seattle, WA (United States)

2016-09-15

Cardiomyopathy in Duchenne muscular dystrophy (DMD) is associated with death in approximately 40% of patients. Echocardiography is routinely used to assess left ventricular (LV) function; however, it has limitations in these patients. We compared echocardiographic measures of cardiac function assessment to cardiac MRI. We included children and young adults with DMD who had MRI performed between January 2010 and July 2015. We measured echocardiographic and MRI parameters of function assessment, including strain. Presence of late gadolinium enhancement (LGE) was assessed by MRI. Subjects were divided into two groups based on MRI left ventricular ejection fraction (LVEF): group I, LVEF ≥55% and group II, LVEF <55%. We included 41 studies in 33 subjects, with 25 in group I and 16 in group II. Mean age of subjects was 13.6 ± 2.8 years and mean duration between echocardiogram and MRI was 7.6 ± 4.1 months. Only 8 of 16 (50%) patients in group II had diminished function on echocardiogram. Echocardiographic images were suboptimal in 16 subjects (39%). Overall, echocardiographic parameters had weak correlation with MRI-derived ejection fraction percentage. MRI-derived myocardial strain assessment has better correlation with MRI ejection fraction as compared to echocardiography-derived strain parameters. Echocardiography-based ventricular functional assessment has weak correlation with MRI parameters in children and young adults with Duchenne muscular dystrophy. While this correlation improves in the subset of subjects with adequate echocardiographic image quality, it remains modest and potentially suboptimal for clinical management. Accordingly, we conclude that MRI should be performed routinely and early in children with DMD, not only for LGE imaging but also for functional assessment. (orig.)

Comparison of left ventricular function assessment between echocardiography and MRI in Duchenne muscular dystrophy

International Nuclear Information System (INIS)

Buddhe, Sujatha; Lewin, Mark; Olson, Aaron; Soriano, Brian D.; Ferguson, Mark

2016-01-01

Cardiomyopathy in Duchenne muscular dystrophy (DMD) is associated with death in approximately 40% of patients. Echocardiography is routinely used to assess left ventricular (LV) function; however, it has limitations in these patients. We compared echocardiographic measures of cardiac function assessment to cardiac MRI. We included children and young adults with DMD who had MRI performed between January 2010 and July 2015. We measured echocardiographic and MRI parameters of function assessment, including strain. Presence of late gadolinium enhancement (LGE) was assessed by MRI. Subjects were divided into two groups based on MRI left ventricular ejection fraction (LVEF): group I, LVEF ≥55% and group II, LVEF <55%. We included 41 studies in 33 subjects, with 25 in group I and 16 in group II. Mean age of subjects was 13.6 ± 2.8 years and mean duration between echocardiogram and MRI was 7.6 ± 4.1 months. Only 8 of 16 (50%) patients in group II had diminished function on echocardiogram. Echocardiographic images were suboptimal in 16 subjects (39%). Overall, echocardiographic parameters had weak correlation with MRI-derived ejection fraction percentage. MRI-derived myocardial strain assessment has better correlation with MRI ejection fraction as compared to echocardiography-derived strain parameters. Echocardiography-based ventricular functional assessment has weak correlation with MRI parameters in children and young adults with Duchenne muscular dystrophy. While this correlation improves in the subset of subjects with adequate echocardiographic image quality, it remains modest and potentially suboptimal for clinical management. Accordingly, we conclude that MRI should be performed routinely and early in children with DMD, not only for LGE imaging but also for functional assessment. (orig.)

Two-dimensional echocardiographic features of right ventricular infarction

International Nuclear Information System (INIS)

D'Arcy, B.; Nanda, N.C.

1982-01-01

Real-time, two-dimensional echocardiographic studies were performed in 10 patients with acute myocardial infarction who had clinical features suggestive of right ventricular involvement. All patients showed right ventricular wall motion abnormalities. In the four-chamber view, seven patients showed akinesis of the entire right ventricular diaphragmatic wall and three showed akinesis of segments of the diaphragmatic wall. Segmental dyskinetic areas involving the right ventricular free wall were identified in four patients. One patient showed a large right ventricular apical aneurysm. Other echocardiographic features included enlargement of the right ventricle in eight cases, paradoxical ventricular septal motion in seven cases, tricuspid incompetence in eight cases, dilation of the stomach in four cases and localized pericardial effusion in two cases. Right ventricular infarction was confirmed by radionuclide methods in seven patients, at surgery in one patient and at autopsy in two patients

Clinical and echocardiographic features of aorto-atrial fistulas

Directory of Open Access Journals (Sweden)

Ananthasubramaniam Karthik

2005-01-01

Full Text Available Abstract Aorto-atrial fistulas (AAF are rare but important pathophysiologic conditions of the aorta and have varied presentations such as acute pulmonary edema, chronic heart failure and incidental detection of the fistula. A variety of mechanisms such as aortic dissection, endocarditis with pseudoaneurysm formation, post surgical scenarios or trauma may precipitate the fistula formation. With increasing survival of patients, particularly following complex aortic reconstructive surgeries and redo valve surgeries, recognition of this complication, its clinical features and echocardiographic diagnosis is important. Since physical exam in this condition may be misleading, echocardiography serves as the cornerstone for diagnosis. The case below illustrates aorto-left atrial fistula formation following redo aortic valve surgery with slowly progressive symptoms of heart failure. A brief review of the existing literature of this entity is presented including emphasis on echocardiographic diagnosis and treatment.

Ia diastolic dysfunction: an echocardiographic grade.

Science.gov (United States)

Pandit, Anil; Mookadam, Farouk; Hakim, Fayaz A; Mulroy, Eoin; Saadiq, Rayya; Doherty, Mairead; Cha, Stephen; Seward, James; Wilansky, Susan

2015-01-01

To demonstrate that a distinct group of patients with Grade Ia diastolic dysfunction who do not conform to present ASE/ESE diastolic grading exists. Echocardiographic and demographic data of the Grade Ia diastolic dysfunction were extracted and compared with that of Grades I and II in 515 patients. The mean of age of the cohort was 75 ± 9 years and body mass index did not differ significantly between the 3 groups (P = 0.45). Measurements of left atrial volume index (28.58 ± 7 mL/m(2) in I, 33 ± 10 mL/m(2) in Ia, and 39 ± 12 mL/m(2) in II P Ia, and 79 ± 15 msec in II P Ia, and 217 ± 57 msec in II P Ia, and 22 ± 8 in II), and lateral E/e' (8 ± 3 in I, 15 ± 6 in Ia, and 18 ± 9 in II P Ia compared with I and II. These findings remained significant even after adjusting for age, gender, diabetes, and smoking. Patients with echocardiographic characteristics of relaxation abnormality (E/A ratio of Ia group. © 2014, Wiley Periodicals, Inc.

MEASUREMENTS OF STRAIN FIELDS DUE TO NANOSCALE PRECIPITATES USING THE PHASE IMAGE METHOD

Directory of Open Access Journals (Sweden)

Patricia Donnadieu

2011-05-01

Full Text Available Owing the phase image method (Hytch, 1998, strain fields can be derived from HREM images. The method is here applied to the nanoscale precipitates responsible for hardening in Aluminum alloys. Since the method is a very sensitive one, we have examined the impact of several aspects of the image quality (noise, fluctuations, distortion. The strain field information derived from the HREM image analysis is further introduced in a simulation of the dislocation motion in the matrix.

3D Tendon Strain Estimation Using High-frequency Volumetric Ultrasound Images: A Feasibility Study.

Science.gov (United States)

Carvalho, Catarina; Slagmolen, Pieter; Bogaerts, Stijn; Scheys, Lennart; D'hooge, Jan; Peers, Koen; Maes, Frederik; Suetens, Paul

2018-03-01

Estimation of strain in tendons for tendinopathy assessment is a hot topic within the sports medicine community. It is believed that, if accurately estimated, existing treatment and rehabilitation protocols can be improved and presymptomatic abnormalities can be detected earlier. State-of-the-art studies present inaccurate and highly variable strain estimates, leaving this problem without solution. Out-of-plane motion, present when acquiring two-dimensional (2D) ultrasound (US) images, is a known problem and may be responsible for such errors. This work investigates the benefit of high-frequency, three-dimensional (3D) US imaging to reduce errors in tendon strain estimation. Volumetric US images were acquired in silico, in vitro, and ex vivo using an innovative acquisition approach that combines the acquisition of 2D high-frequency US images with a mechanical guided system. An affine image registration method was used to estimate global strain. 3D strain estimates were then compared with ground-truth values and with 2D strain estimates. The obtained results for in silico data showed a mean absolute error (MAE) of 0.07%, 0.05%, and 0.27% for 3D estimates along axial, lateral direction, and elevation direction and a respective MAE of 0.21% and 0.29% for 2D strain estimates. Although 3D could outperform 2D, this does not occur in in vitro and ex vivo settings, likely due to 3D acquisition artifacts. Comparison against the state-of-the-art methods showed competitive results. The proposed work shows that 3D strain estimates are more accurate than 2D estimates but acquisition of appropriate 3D US images remains a challenge.

Effects that different types of sports have on the hearts of children and adolescents and the value of two-dimensional strain-strain-rate echocardiography.

Science.gov (United States)

Binnetoğlu, Fatih Köksal; Babaoğlu, Kadir; Altun, Gürkan; Kayabey, Özlem

2014-01-01

Whether the hypertrophy found in the hearts of athletes is physiologic or a risk factor for the progression of pathologic hypertrophy remains controversial. The diastolic and systolic functions of athletes with left ventricular (LV) hypertrophy usually are normal when measured by conventional methods. More precise assessment of global and regional myocardial function may be possible using a newly developed two-dimensional (2D) strain echocardiographic method. This study evaluated the effects that different types of sports have on the hearts of children and adolescents and compared the results of 2D strain and strain-rate echocardiographic techniques with conventional methods. Athletes from clubs for five different sports (basketball, swimming, football, wrestling, and tennis) who had practiced regularly at least 3 h per week during at least the previous 2 years were included in the study. The control group consisted of sedentary children and adolescents with no known cardiac or systemic diseases (n = 25). The athletes were grouped according to the type of exercise: dynamic (football, tennis), static (wrestling), or static and dynamic (basketball, swimming). Shortening fraction and ejection fraction values were within normal limits for the athletes in all the sports disciplines. Across all 140 athletes, LV geometry was normal in 58 athletes (41.4 %), whereas 22 athletes (15.7 %) had concentric remodeling, 20 (14.3 %) had concentric hypertrophy, and 40 (28.6 %) had eccentric hypertrophy. Global LV longitudinal strain values obtained from the average of apical four-, two-, and three-chamber global strain values were significantly lower for the basketball players than for all the other groups (p < 0.001).

ANTHROPOMORPHIC PHANTOMS FOR ASSESSMENT OF STRAIN IMAGING METHODS INVOLVING SALINE-INFUSED SONOHYSTEROGRAPHY

Science.gov (United States)

Hobson, Maritza A.; Madsen, Ernest L.; Frank, Gary R.; Jiang, Jingfeng; Shi, Hairong; Hall, Timothy J.; Varghese, Tomy

2008-01-01

Two anthropomorphic uterine phantoms were developed which allow assessment and comparison of strain imaging systems adapted for use with saline-infused sonohysterography (SIS). Tissue-mimicking (TM) materials consist of dispersions of safflower oil in gelatin. TM fibroids are stiffer than the TM myometrium/cervix and TM polyps are softer. The first uterine phantom has 3-mm diameter TM fibroids randomly distributed in TM myometrium. The second uterine phantom has a 5-mm and an 8-mm spherical TM fibroid in addition to a 5-mm spherical and a 12.5-mm long (medicine-capsule-shaped) TM endometrial polyp protruding into the endometrial cavity; also, a 10-mm spherical TM fibroid projects from the serosal surface. Strain images using the first phantom show the stiffer 3-mm TM fibroids in the myometrium. Results from the second uterine phantom show that, as expected, parts of inclusions projecting into the uterine cavity will appear very stiff, whether they are stiff or soft. Results from both phantoms show that even though there is a five-fold difference in the Young’s moduli values, there is not a significant difference in the strain in the transition from the TM myometrium to the TM fat. These phantoms allow for realistic comparison and evolution of SIS strain imaging techniques and can aid clinical personnel to develop skills for SIS strain imaging. PMID:18514999

Evaluation of area strain response of dielectric elastomer actuator using image processing technique

Science.gov (United States)

Sahu, Raj K.; Sudarshan, Koyya; Patra, Karali; Bhaumik, Shovan

2014-03-01

Dielectric elastomer actuator (DEA) is a kind of soft actuators that can produce significantly large electric-field induced actuation strain and may be a basic unit of artificial muscles and robotic elements. Understanding strain development on a pre-stretched sample at different regimes of electrical field is essential for potential applications. In this paper, we report about ongoing work on determination of area strain using digital camera and image processing technique. The setup, developed in house consists of low cost digital camera, data acquisition and image processing algorithm. Samples have been prepared by biaxially stretched acrylic tape and supported between two cardboard frames. Carbon-grease has been pasted on the both sides of the sample, which will be compliant with electric field induced large deformation. Images have been grabbed before and after the application of high voltage. From incremental image area, strain has been calculated as a function of applied voltage on a pre-stretched dielectric elastomer (DE) sample. Area strain has been plotted with the applied voltage for different pre-stretched samples. Our study shows that the area strain exhibits nonlinear relationship with applied voltage. For same voltage higher area strain has been generated on a sample having higher pre-stretched value. Also our characterization matches well with previously published results which have been done with costly video extensometer. The study may be helpful for the designers to fabricate the biaxial pre-stretched planar actuator from similar kind of materials.

Can echocardiographic findings predict falls in older persons?

NARCIS (Netherlands)

N. van der Velde (Nathalie); B.H.Ch. Stricker (Bruno); J.R.T.C. Roelandt (Jos); F.J. ten Cate (Folkert); T.J.M. van der Cammen (Tischa)

2007-01-01

textabstractBackground. The European and American guidelines state the need for echocardiography in patients with syncope. 50% of older adults with syncope present with a fall. Nonetheless, up to now no data have been published addressing echocardiographic abnormalities in older fallers. Method and

Reversal of echocardiographic right-sided heart pathology in a dog with severe pulmonary hypertension: a case report

Directory of Open Access Journals (Sweden)

McMahon P

2015-06-01

Full Text Available Peggy McMahon,1 Carley Saelinger 2  1Emergency and Critical Care Department, 2Cardiology Department, Animal Specialty and Emergency Center, Los Angeles, CA, USA Abstract: Pathologic right-sided heart changes are a common echocardiographic finding in patients with pulmonary hypertension (PH. Canines with PH may have right heart pathology documented via echocardiographic color Doppler interrogation including tricuspid valve regurgitation, pulmonic valve insufficiency, elevated pulmonary arterial systolic pressure, elevated pulmonary arterial diastolic pressure, and alterations in ejection profiles. Two-dimensional echocardiographic findings may include right ventricular hypertrophy, interventricular septal flattening, paradoxical interventricular septal motion, pulmonary artery dilation, and potentially abnormal left heart dimensions. In veterinary medicine, much confidence is given to the measurement of pulmonary arterial systolic pressure estimated from tricuspid valve regurgitation to grade the severity of PH and monitor its improvement with little emphasis placed on the integration of two-dimensional echocardiographic right and left heart pathology in conjunction with Doppler findings. To the authors’ knowledge, marked improvement and/or resolution of echocardiographic-documented right heart pathology have not been previously reported in the veterinary literature. This case report documents profound echocardiographic improvement of right-sided heart disease in a dog with severe PH. Keywords: canine, pulmonary hypertension, tricuspid valve regurgitation, right heart hypertrophy, sildenafil  

X-ray picture of the heart turn in echocardiographic diagnosis of rheumatic heart disease

International Nuclear Information System (INIS)

Grishkevich, A.M.; Goryanina, N.K.

1986-01-01

The paper is concerned with X-ray and echocardiographic investigation of the heart in 461 patients with mitral-tricuspidal disease. In 377 (82%) cases a turn of the heart along the longitudinal axis (counter clockwise) to the left and back was revealed. X-ray recognition of the heart turn made it possible to set an echocardiographic sensor to spot some of the cardiac cavities, interventricular septum and valvular apparatus. The correct setting of the echocardiographic sensor resulted in the determination of true sizes of each cardiac cavity, diagnosis of the nature of each valvular lesion and the recognition of such complications of rheumatic heart diseases as valvular calcinosis, left atrial thrombosis and disorder of myocardial contractility

Quantification of mitral regurgitation on cardiac computed tomography: comparison with qualitative and quantitative echocardiographic parameters.

LENUS (Irish Health Repository)

Arnous, Samer

2012-02-01

PURPOSE: To assess whether cardiac computed tomographic angiography (CCTA) can quantify the severity of chronic mitral regurgitation (MR) compared to qualitative and quantitative echocardiographic parameters. MATERIALS AND METHODS: Cardiac computed tomographic angiography was performed in 23 patients (mean +\\/- SD age, 63 +\\/- 16 years; range, 24-86 years) with MR and 20 patients without MR (controls) as determined by transthoracic echocardiography. Multiphasic reconstructions (20 data sets reconstructed at 5% increments of the electrocardiographic gated R-R interval) were used to analyze the mitral valve. Using CCTA planimetry, 2 readers measured the regurgitant mitral orifice area (CCTA ROA) during systole. A qualitative echocardiographic assessment of severity of MR was made by visual assessment of the length of the regurgitant jet. Quantitative echocardiographic measurements included the vena contracta, proximal isovelocity surface area, regurgitant volume, and estimated regurgitant orifice (ERO). Comparisons were performed using the independent t test, and correlations were assessed using the Spearman rank test. RESULTS: All controls and the patients with MR were correctly identified by CCTA. For patients with mild, moderate, or severe MR, mean +\\/- SD EROs were 0.16 +\\/- 0.03, 0.31 +\\/- 0.08, and 0.52 +\\/- 0.03 cm(2) (P < 0.0001) compared with mean +\\/- SD CCTA ROAs 0.09 +\\/- 0.05, 0.30 +\\/- 0.04, and 0.97 +\\/- 0.26 cm(2) (P < 0.0001), respectively. When echocardiographic measurements were graded qualitatively as mild, moderate, or severe, strong correlations were seen with CCTA ROA (R = 0.89; P < 0.001). When echocardiographic measurements were graded quantitatively, the vena contracta and the ERO showed modest correlations with CCTA ROA (0.48 and 0.50; P < 0.05 for both). Neither the proximal isovelocity surface area nor the regurgitant volume demonstrated significant correlations with CCTA ROA. CONCLUSIONS: Single-source 64-slice CCTA provides a

Can echocardiographic findings predict falls in older persons?

NARCIS (Netherlands)

van der Velde, Nathalie; Stricker, Bruno H. Ch; Roelandt, Jos R. T. C.; ten Cate, Folkert J.; van der Cammen, Tischa J. M.

2007-01-01

BACKGROUND: The European and American guidelines state the need for echocardiography in patients with syncope. 50% of older adults with syncope present with a fall. Nonetheless, up to now no data have been published addressing echocardiographic abnormalities in older fallers. METHOD AND FINDINGS: In

Echocardiographic Evaluation of Patent Ductus Arteriosus in Preterm Infants

Directory of Open Access Journals (Sweden)

Romaine Arlettaz

2017-06-01

Full Text Available Patent ductus arteriosus (PDA is part of the typical morbidity profile of the preterm infant, with a high incidence of 80–90% in extremely low birth weight infants born before 26 weeks of gestation. Whereas spontaneous closure of the ductus arteriosus (DA is likely in term infants, it is less so in preterm ones. PDA is associated with increased mortality and various comorbidities including cardiac failure, need for respiratory support, bronchopulmonary dysplasia, pulmonary or intracranial hemorrhage, and necrotizing enterocolitis; however, there is no proven causality between these morbidities and the presence of DA. Thus, the indication to close PDA remains highly controversial. This paper focuses on echocardiographic evaluation of PDA in the preterm infant and particularly on the echocardiographic signs of hemodynamic significance.

Strain Imaging Using Terahertz Waves and Metamaterials

Science.gov (United States)

2016-11-01

predictions. 14. SUBJECT TERMS Birefringence, Terahertz Waves, Metamaterials 15. NUMBER OF PAGES 16 16. PRICE CODE 17. SECURITY...opaque objects by using the principles of strain-induced birefringence. 4 III. CONCEPT To overcome the inability of visual light to penetrate ...opaque objects, terahertz radiation was investigated. Longer wavelength EM waves, such as radio waves, have excellent penetration ability but low image

Childhood acquired heart disease in Nigeria: an echocardiographic ...

African Journals Online (AJOL)

Introduction: Acquired heart diseases (AHD) are not uncommon in children. The current multi-center study aims to provide a more representative data of AHD in Nigeria. Methods: Over 42 months, children referred for echocardiographic evaluation who had confirmed AHD in three centers in Nigeria were recruited. The data ...

Myocardial strain assessment by cine cardiac magnetic resonance imaging using non-rigid registration.

Science.gov (United States)

Tsadok, Yossi; Friedman, Zvi; Haluska, Brian A; Hoffmann, Rainer; Adam, Dan

2016-05-01

To evaluate a novel post-processing method for assessment of longitudinal mid-myocardial strain in standard cine cardiac magnetic resonance (CMR) imaging sequences. Cine CMR imaging and tagged cardiac magnetic resonance imaging (TMRI) were performed in 15 patients with acute myocardial infarction (AMI) and 15 healthy volunteers served as control group. A second group of 37 post-AMI patients underwent both cine CMR and late gadolinium enhancement (LGE) CMR exams. Speckle tracking echocardiography (STE) was performed in 36 of these patients. Cine CMR, TMRI and STE were analyzed to obtain longitudinal strain. LGE-CMR datasets were analyzed to evaluate scar extent. Comparison of peak systolic strain (PSS) measured from CMR and TMRI yielded a strong correlation (r=0.86, pcine CMR data. The method was found to be highly correlated with strain measurements obtained by TMRI and STE. This tool allows accurate discrimination between different transmurality states of myocardial infarction. Copyright © 2015 Elsevier Inc. All rights reserved.

Echocardiographic study of left atrial myxoma

Directory of Open Access Journals (Sweden)

Dalal J

1979-01-01

Full Text Available Four cases of left atrial myxoma were diagnosed pre-operatively by echocardiography. All cases showed characteristic echocardio-graphic features of variegated shadows behind the mitral valve in diastole and within the left atrium in systole. In two cases the my-xomas were surgically removed and confirmed on histology. In one case the post-operative echocardiogram showed complete dis-appearance of the abnormal shadows. Echocardiography is the most reliable method today for the diagnosis of a myxoma.

Strain bidimensional na cardiopatia de Takotsubo Two-dimensional strain in Takotsubo cardiomyopathy

Directory of Open Access Journals (Sweden)

Carlos Bellini G. Gomes

2010-08-01

Full Text Available Este relato apresenta o seguimento tardio de um caso de cardiomiopatia de Takotsubo com boa evolução clínica e melhora da função sistólica global ventricular esquerda. Contudo, observou-se persistência de significativa disfunção sistólica regional longitudinal que foi avaliada por meio de nova técnica ecocardiográfica (speckle tracking, com as medidas do strain (S e strain rate (SR correspondentes. Ressaltamos a importância desse novo método para o acompanhamento dessa cardiopatia, pois permite identificar os pacientes que persistem com disfunção sistólica e que possivelmente serão beneficiados com a manutenção da terapêutica clínica.This report presents the late follow-up of a case of Takotsubo cardiomyopathy with good clinical outcome and improved left ventricular global systolic function. However, there was persistence of significant regional longitudinal systolic dysfunction evaluated using a new echocardiographic technique (speckle tracking, with corresponding measures of strain (S and strain rate (SR. We emphasize the importance of this new method to monitoring this cardiomyopathy, since it identifies patients with persistent systolic dysfunction who will possibly benefit from maintenance of clinical therapy

Intravenous carbon dioxide as an echocardiographic contrast agent

NARCIS (Netherlands)

R.S. Meltzer (Richard); P.W.J.C. Serruys (Patrick); P.G. Hugenholtz (Paul); J.R.T.C. Roelandt (Jos)

1981-01-01

textabstractIntravenous carbon dioxide (CO2) was employed to cause echocardiographic contrast in 40 patients. One to 3 cc of medically pure CO2 were agitated with 5 to 8 cc of 5% dextrose in water and rapidly injected into an upper extremity vein. Contrast was obtained in all patients. In 33

Morphologic-echocardiographic correlates of Ebstein's malformation.

Science.gov (United States)

Rusconi, P G; Zuberbuhler, J R; Anderson, R H; Rigby, M L

1991-07-01

The cross-sectional echocardiographic findings were analysed retrospectively in 26 patients with Ebstein's malformation in the light of studies of autopsied specimens from different patients showing this lesion. The salient anatomical feature in diagnosis is the finding of the hinge point of the septal and mural leaflets of the valve within the inlet component of the right ventricle rather than at the atrioventricular junction. The other important feature is the nature of the distal attachment of the leaflets, particularly the anterosuperior one, which can either be in focal or linear fashion. The hinge point of the septal leaflet was noted echocardiographically to be displaced in 19 patients but, significantly, the leaflet was absent in the other seven. Also significant was that the hinge point of the mural leaflet at the crux had been visualized in only 15 of the patients. The anterosuperior leaflet had a distal linear attachment in 20 of the patients, with the anteroseptal commissure becoming a keyhole in six of these through which blood passed to the functional right ventricle. The valve remained a competent structure, even though closing at the junction of atrialized and functional components of the right ventricle rather than at the atrioventricular junction. Cross-sectional echocardiography is the technique of choice with which to display the salient morphological features of Ebstein's malformation.

Clinical and echocardiographic findings of patients with suspected acute pulmonary thromboembolism who underwent computed tomography pulmonary angiography

Directory of Open Access Journals (Sweden)

Atoosa Adibi

2016-01-01

Full Text Available Background: The aim of the study was to determine the correlation between clinical and echocardiographic findings and risk factors of patients with suspected acute pulmonary thromboembolism (PTE who underwent computed tomography pulmonary angiography (CTPA. Materials and Methods: In this cross-sectional study, 310 hospitalized patients aged >18 years with high clinical suspicion of PTE referred to imaging center of our hospital from different wards for CTPA were enrolled. The frequency of different clinical presentations, risk factors, items of Wells' criteria, and echocardiographic findings was compared in patients with and without PTE, which have been diagnosed according to the CTPA results. Results: PTE was diagnosed in 53 (17.1% of patients with suspected PTE. From clinical manifestations, tachypnea, pleuritic chest pain, and edema of lower extremities were significantly more frequent among patients with PTE (P < 0.05. Major surgery was the risk factor which was significantly more prevalent among patients with PTE (P < 0.05. Frequency of all criteria of Wells' criteria, except hemoptysis, was significantly higher in patients with PTE (P < 0.05. The frequency of all studied echocardiographic variables was significantly higher in patients with PTE (P < 0.05. Conclusion: It is suggested that we could use the results of this study for utilizing the diagnostic process of PTE in patients with highly clinical suspicion of PTE and providing more validated decision. Using the results of this study, we could identify high-risk patients and made appropriate risk assessment for better management of patients with suspected PTE as well as reduce the rate of unnecessary CTPA and its related adverse consequences.

Speckle-tracking strain assessment of left ventricular dysfunction in synthetic cannabinoid and heroin users.

Science.gov (United States)

Demirkıran, Aykut; Albayrak, Neslihan; Albayrak, Yakup; Zorkun, Cafer Sadık

2018-06-01

There is growing evidence regarding the numerous adverse effects of synthetic cannabinoids (SCBs) on the cardiovascular system; however, no studies have shown the cardiovascular effects of opioids using strain echocardiography. This study examines the cardiac structure and function using echocardiographic strain imaging in heroin and synthetic cannabinoid users. This double-blind study included patients who were admitted or referred to a rehabilitation center for heroin (n=31) and synthetic cannabinoid users (n=30). Heroin users and synthetic cannabinoid users were compared with healthy volunteers (n=32) using two-dimensional (2D) speckle-tracking (ST) echocardiography. No differences were found in the baseline characteristics and 2D echocardiography values. The mean global longitudinal strain value was -20.5%±2.4% for SCB users, -22.3%±2.4% for opioid users, and -22.5%±2.2% for healthy volunteers (p=0.024). The mean apical 2-chamber (AP2C) L-strain values were -20.1%±3.1%, -22.4%±3.0%, and -22.3%±2.8% for SCB users, opioid users, and healthy volunteers, respectively (p=0.032). The mean apical 4-chamber (AP4C) L-strain values were -20.7%±2.5% for SCB users, -23.2%±3.2% for opioid users, and -23.8%±3.1% for healthy volunteers (p<0.001). SCBs are potential causes of subclinical left ventricular dysfunction.

Assessment of left ventricular function: comparison between radionuclide angiography and semiquantitative two-dimensional echocardiographic analysis

International Nuclear Information System (INIS)

Gottsauner-Wolf, M.; Schedlmayer-Duit, J.; Porenta, G.; Gwechenberger, M.; Huber, K.; Glogar, D.; Probst, P.; Sochor, H.

1996-01-01

Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent RNA were assessed with 2D-echo within 3 months. In addition, 92 of these patients also underwent CVG (correlation of ejection fraction between CVG and RNA: r=0.82; P<0.0001). The RNA mean ejection fractions in the four 2D-echo groups (0=normal, 1=slightly, 2=moderate, or 3=severe reduced left ventricular function) differed markedly (P<0.0001); however, there was overlapping among the groups (2D-echo score/RNA ejection fraction: 0=57.3%±12.8%; 1=46.0%±12.9%; 2=29.6%± 12.2%; and 3=24.6%±11.5%) and the difference between 2D-echo scores 2 and 3 was not significant. 2D-echo showed a good concordance in RNA classes (0=≥505; 1=35%-49%; 2=21%-34%; and 3=≤20% ejection fraction) 0 (133/166; 80%) and 3 (18/30; 60%) but low concordance in classes 1 (27/82; 33%) and 2 (21/61; 34%). For accurate assessment of global left ventricular ejection fraction, visual semiquantitative judgement of a 2D echocardiographic image is limited in comparison to CVG or RNA, especially in patients with a slight or moderate reduction in left ventricular ejection fraction. (orig.). With 2 figs., 2 tabs

Echocardiographic screening for subclinical rheumatic heart disease remains a research tool pending studies of impact on prognosis.

Science.gov (United States)

Zühlke, Liesl; Mayosi, Bongani M

2013-03-01

The application of portable echocardiography to the screening of asymptomatic children and young adults for rheumatic heart disease (RHD) in developing countries indicates that the disease may affect 62 million to 78 million individuals worldwide, which could potentially result in 1.4 million deaths per year from RHD and its complications. The World Heart Federation has developed a guideline for the echocardiographic diagnosis of RHD in asymptomatic individuals without a history of acute rheumatic fever (ARF) in order to ensure the reliability, comparability, and reproducibility of findings of the echocardiographic screening studies. Early studies suggest that a third of individuals with asymptomatic subclinical RHD revert to normal echocardiographic findings on repeat testing after 6-12 months, suggesting that repeat echocardiography may be necessary to confirm the findings prior to consideration of interventions such as antibiotic prophylaxis. It is not known, however, whether echocardiographic screening for asymptomatic subclinical RHD or the introduction of antibiotic prophylaxis for affected individuals improves the prognosis of RHD. Furthermore, the cost-effectiveness of this screening method has not been established in the vast majority of affected countries. Therefore, echocardiographic screening for asymptomatic subclinical RHD remains a research tool until studies of impact on prognosis and cost-effectiveness are conducted.

A parallelizable real-time motion tracking algorithm with applications to ultrasonic strain imaging

International Nuclear Information System (INIS)

Jiang, J; Hall, T J

2007-01-01

Ultrasound-based mechanical strain imaging systems utilize signals from conventional diagnostic ultrasound systems to image tissue elasticity contrast that provides new diagnostically valuable information. Previous works (Hall et al 2003 Ultrasound Med. Biol. 29 427, Zhu and Hall 2002 Ultrason. Imaging 24 161) demonstrated that uniaxial deformation with minimal elevation motion is preferred for breast strain imaging and real-time strain image feedback to operators is important to accomplish this goal. The work reported here enhances the real-time speckle tracking algorithm with two significant modifications. One fundamental change is that the proposed algorithm is a column-based algorithm (a column is defined by a line of data parallel to the ultrasound beam direction, i.e. an A-line), as opposed to a row-based algorithm (a row is defined by a line of data perpendicular to the ultrasound beam direction). Then, displacement estimates from its adjacent columns provide good guidance for motion tracking in a significantly reduced search region to reduce computational cost. Consequently, the process of displacement estimation can be naturally split into at least two separated tasks, computed in parallel, propagating outward from the center of the region of interest (ROI). The proposed algorithm has been implemented and optimized in a Windows (registered) system as a stand-alone ANSI C++ program. Results of preliminary tests, using numerical and tissue-mimicking phantoms, and in vivo tissue data, suggest that high contrast strain images can be consistently obtained with frame rates (10 frames s -1 ) that exceed our previous methods

A three-frame digital image correlation (DIC) method for the measurement of small displacements and strains

International Nuclear Information System (INIS)

Cofaru, C; Philips, W; Van Paepegem, W

2012-01-01

Digital image correlation (DIC) has become a well-established approach for the calculation of full-field displacement and strains within the field of experimental mechanics. Since their introduction, DIC methods have been relying on only two images to measure the displacements and strains that materials undergo under load. It can be foreseen that the use of additional image information for the calculus of displacements and strains, although computationally more expensive, can positively impact DIC method accuracy under both ideal and challenging experimental conditions. Such accuracy improvements are especially important when measuring very small deformations, which still constitutes a great challenge: small displacements and strains translate into equally small digital image intensity changes on the material’s surface, which are affected by the digitization processes of the imaging hardware and by other image acquisition effects such as image noise. This paper proposes a new three-frame Newton–Raphson DIC method and evaluates it from the standpoints of accuracy and speed. The method models the deformations that are to be measured under the assumption that the deformation occurs at approximately the same rate between each two consecutive images in the three image sequences that are employed. The aim is to investigate how the use of image data from more than two images impacts accuracy and what is the effect on the computational speed. The proposed method is compared with the classic two-frame Newton–Raphson method in three experiments. Two experiments rely on numerically deformed images that simulate heterogeneous deformations. The third experiment uses images from a real deformation experiment. Results indicate that although it is computationally more demanding, the three-frame method significantly improves displacement and strain accuracy and is less sensitive to image noise. (paper)

Strain and displacement controls by fibre bragg grating and digital image correlation

DEFF Research Database (Denmark)

Waldbjørn, Jacob Paamand; Høgh, Jacob Herold; Schmidt, Jacob Wittrup

2014-01-01

the test based on measurements performed directly on the test specimen. In this paper, fibre Bragg grating (FBG) and Digital Image Correlation (DIC) are used to control a test. The FBG sensors offer the possibility of measuring strains inside the specimen, while the DIC system measures strains...

A meta-analysis for the echocardiographic assessment of right ventricular structure and function in ARVC: a Study by the Research and Audit Committee of the British Society of Echocardiography

Directory of Open Access Journals (Sweden)

Mohammad Qasem

2016-10-01

Full Text Available Introduction: Arrhythmogenic right ventricular cardiomyopathy ARVC is an inherited pathology that can increase the risk of sudden death. Current task force criteria for echocardiographic diagnosis do not include new, regional assessment tools which may be relevant in a phenotypically diverse disease. We adopted a systematic review and meta-analysis approach to highlight echocardiographic indices that differentiated ARVC patients and healthy controls. Methods: Data was extracted and analysed from prospective trials that employed a case–control design meeting strict inclusion and exclusion as well as a priori quality criteria. Structural indices included proximal RV outflow tract (RVOT1 and RV diastolic area (RVDarea. Functional indices included RV fractional area change (RVFAC, tricuspid annular systolic excursion (TAPSE, peak systolic and early diastolic myocardial velocities (S′ and E′, respectively and myocardial strain. Results: Patients with ARVC had larger RVOT1 (mean ± s.d.; 34 vs 28 mm, P < 0.001 and RVDarea (23 vs 18 cm2, P < 0.001 compared with healthy controls. ARVC patients also had lower RVFAC (38 vs 46%, P < 0.001, TAPSE (17 vs 23 mm, P < 0.001, S′ (9 vs 12 cm/s, P < 0.001, E′ (9 vs 13 cm/s, P < 0.001 and myocardial strain (−17 vs −30%, P < 0.001. Conclusion: The data from this meta-analysis support current task force criteria for the diagnosis of ARVC. In addition, other RV measures that reflect the complex geometry and function in ARVC clearly differentiated between ARVC and healthy controls and may provide additional diagnostic and management value. We recommend that future working groups consider this data when proposing new/revised criteria for the echocardiographic diagnosis of ARVC.

Assessment of right ventricular longitudinal strain by 2D speckle tracking imaging compared with RV function and hemodynamics in pulmonary hypertension.

Science.gov (United States)

Li, Yidan; Wang, Yidan; Meng, Xiangli; Zhu, Weiwei; Lu, Xiuzhang

2017-11-01

The right ventricular longitudinal strain (RVLS) of pulmonary hypertension (PH) patients and its relationship with RV function parameters measured by echocardiography and hemodynamic parameters measured by right heart catheterization was investigated. According to the WHO functional class (FC), 66 PH patients were divided into FC I/II (group 1) and III/IV (group 2). RV function parameters were measured by echocardiographic examinations. Hemodynamic parameters were obtained by right heart catheterization. Patients in group 2 had higher systolic pulmonary artery pressure (sPAP; P good sensitivity and specificity. Evidence has shown that RVLS measurement can provide the much-needed and reliable information on RV function and hemodynamics. Therefore, this qualifies as a patient-friendly approach for the clinical management of PH patients.

Measurement of Strain in the Left Ventricle during Diastole withcine-MRI and Deformable Image Registration

Energy Technology Data Exchange (ETDEWEB)

Veress, Alexander I.; Gullberg, Grant T.; Weiss, Jeffrey A.

2005-07-20

The assessment of regional heart wall motion (local strain) can localize ischemic myocardial disease, evaluate myocardial viability and identify impaired cardiac function due to hypertrophic or dilated cardiomyopathies. The objectives of this research were to develop and validate a technique known as Hyperelastic Warping for the measurement of local strains in the left ventricle from clinical cine-MRI image datasets. The technique uses differences in image intensities between template (reference) and target (loaded) image datasets to generate a body force that deforms a finite element (FE) representation of the template so that it registers with the target image. To validate the technique, MRI image datasets representing two deformation states of a left ventricle were created such that the deformation map between the states represented in the images was known. A beginning diastoliccine-MRI image dataset from a normal human subject was defined as the template. A second image dataset (target) was created by mapping the template image using the deformation results obtained from a forward FE model of diastolic filling. Fiber stretch and strain predictions from Hyperelastic Warping showed good agreement with those of the forward solution. The technique had low sensitivity to changes in material parameters, with the exception of changes in bulk modulus of the material. The use of an isotropic hyperelastic constitutive model in the Warping analyses degraded the predictions of fiber stretch. Results were unaffected by simulated noise down to an SNR of 4.0. This study demonstrates that Warping in conjunction with cine-MRI imaging can be used to determine local ventricular strains during diastole.

Echocardiograph alterations in asthma patients

Directory of Open Access Journals (Sweden)

André Luís Mancini

2008-05-01

Full Text Available Introduction: Asthma is a chronic inflammatory disease which has increased during the last 20 years, putting a strain on medical resources, particularly severe forms of the disease. Treatment in such cases is inhaled corticosteroids and beta agonist drugs that can produce a range of side effects. The aim of this study is to identify echocardiograph abnormalities and correlate them with severity of disease. Methodology: Eight-seven outpatients were selected at the asthma unit of the Gaffree Guinle University Hospital (HUGG. Each patient underwent spirometry, electrocardiogram (ECG and echocardiogram (ECO during the trial within a month maximum. Echocardiograph abnormalities found related to degree of asthma. Statistical analysis was made by nonparametric tests. Results: We found significant differences (p ≤ 0.05 for age, disease duration and haemoglobin saturation (SaO2 between the moderate and severe groups. In the sample a high prevalence of tricuspid insufficiency (41.4% was identified. Conclusions: ECO identified a series of abnormalities that were not always dependent on severity of disease. ECO can identify pulmonary hypertension through calculation of mean pressure of the pulmonary artery. Resumo: Introdução: A asma é uma doença inflamatória crónica cuja prevalência vem aumentando nos últimos 20 anos. Demanda grande utilização de recursos, principalmente no grupo grave. Neste, há consumo crónico de corticóides inalatórios e de β2-agonistas, que podem produzir uma série de problemas. O objectivo deste trabalho é o de rastrear as alterações electro e ecocardiográficas e relacioná-las ao grau da asma. Metodologia: Selecionámos 87 doentes do ambulatório de asma do HUGG, que, por rotina, possuem uma espirografia, um eletrocardiograma (ECG e um ecocardiograma (ECO feitos com um intervalo máximo de um mês. As alterações ecocardiográficas encontradas

Echocardiographic and clinical outcomes of central versus noncentral percutaneous edge-to-edge repair of degenerative mitral regurgitation

DEFF Research Database (Denmark)

Estévez-Loureiro, Rodrigo; Franzen, Olaf; Winter, Reidar

2013-01-01

This study aimed to assess the clinical and echocardiographic results of MitraClip implantation in noncentral degenerative mitral regurgitation (dMR) compared with central dMR.......This study aimed to assess the clinical and echocardiographic results of MitraClip implantation in noncentral degenerative mitral regurgitation (dMR) compared with central dMR....

Utility of Tissue Doppler Imaging in the Echocardiographic Evaluation of Left and Right Ventricular Function in Dogs with Myxomatous Mitral Valve Disease with or without Pulmonary Hypertension.

Science.gov (United States)

Baron Toaldo, M; Poser, H; Menciotti, G; Battaia, S; Contiero, B; Cipone, M; Diana, A; Mazzotta, E; Guglielmini, C

2016-05-01

In human medicine, right ventricular (RV) functional parameters represent a tool for risk stratification in patients with congestive heart failure caused by left heart disease. Little is known about RV alterations in dogs with left-sided cardiac disorders. To assess RV and left ventricular (LV) function in dogs with myxomatous mitral valve disease (MMVD) with or without pulmonary hypertension (PH). One-hundred and fourteen dogs: 28 healthy controls and 86 dogs with MMVD at different stages. Prospective observational study. Animals were classified as healthy or having MMVD at different stages of severity and according to presence or absence of PH. Twenty-eight morphological, echo-Doppler, and tissue Doppler imaging (TDI) variables were measured and comparison among groups and correlations between LV and RV parameters were studied. No differences were found among groups regarding RV echo-Doppler and TDI variables. Sixteen significant correlations were found between RV TDI and left heart echocardiographic variables. Dogs with PH had significantly higher transmitral E wave peak velocity and higher E/e' ratio of septal (sMV) and lateral (pMV) mitral annulus. These 2 variables were found to predict presence of PH with a sensitivity of 84 and 72%, and a specificity of 71 and 80% at cut-off values of 10 and 9.33 for sMV E/e' and pMV E/e', respectively. No association between variables of RV function and different MMVD stage and severity of PH could be detected. Some relationships were found between echocardiographic variables of right and left ventricular function. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Recent advances in echocardiography for valvular heart disease.

Science.gov (United States)

Hahn, Rebecca

2015-01-01

Echocardiography is the imaging modality of choice for the assessment of patients with valvular heart disease. Echocardiographic advancements may have particular impact on the assessment and management of patients with valvular heart disease. This review will summarize the current literature on advancements, such as three-dimensional echocardiography, strain imaging, intracardiac echocardiography, and fusion imaging, in this patient population.

The application of a 3 dimensional image scanner to the strain measurement

International Nuclear Information System (INIS)

Mazda, Taiji; Ogawa, Hiroshi; Suzuki, Michiaki; Nakano, Yasuo.

1993-01-01

A large strain measuring method for a laminated seismic isolation rubber, which will be introduced to reactor buildings of the Demonstration Fast Breeder Reactor (DFBR), was developed. With using strain gages, it is difficult to measure the large strain under the large displacement condition. With using the optical instruments, it is also impossible to measure the strain of a 3 dimensional object. We developed a new measuring method in which strain is calculated from a 3 dimensional deformation with using a 3 dimensional image scanner. This method is noncontact measuring method, and it can measure the strain of a 3 dimensional object under the large deformation. This work is one part of 'The Development of FBR Seismic Isolation system' operated by Central Research Institute of Electric Power Industry. (author)

Identification of Trichoderma strains by image analysis of HPLC chromatograms

DEFF Research Database (Denmark)

Thrane, Ulf; Poulsen, S.B.; Nirenberg, H.I.

2001-01-01

Forty-four Trichoderma strains from water-damaged building materials or indoor dust were classified with chromatographic image analysis on full chromatographic matrices obtained by high performance liquid chromatography with UV detection of culture extracts. The classes were compared with morphol...

Echocardiographic reference ranges for sedentary donkeys in the UK.

Science.gov (United States)

Roberts, S L; Dukes-McEwan, J

2016-10-01

The aim of this study was to provide two-dimensional (2D) and M-mode echocardiographic reference ranges from a sample of the UK population of donkeys including geriatrics (>30 years), owned by The Donkey Sanctuary, and to assess the influence of gender, weight and age on these variables. A total of 36 donkeys with no clinical or echocardiographic evidence of cardiovascular disease were examined; 24 geldings and 12 females, aged 3-45 years old, weighing 130-262 kg. Left atrial to aortic ratio was larger in geldings (P=0.004). There was no significant difference for left ventricular M-mode diastolic diameter between females and geldings (P=0.121) after exclusion of one heavy female outlier. 2D measurements significantly increased with bodyweight including maximal left atrial diameter (R(2)=0.112; P=0.046), aortic diameter at various levels (e.g. annulus: R(2)=0.35; Pdonkeys across a wide age range and shows differences compared with reference ranges from working donkeys. British Veterinary Association.

Imaging of the strain field around precipitate particles using transmission ion channeling

NARCIS (Netherlands)

King, PJC; Breese, MBH; Meekeson, D; Smulders, PJM; Wilshaw, PR; Grime, GW

1996-01-01

This paper shows ion channeling images of the strain field produced by precipitate particles in a crystal matrix. Images have been produced by mapping the energy of 3 MeV protons transmitted through a thinned silicon crystal containing colonies of copper silicide particles, with the incident beam at

Echocardiographic evaluation of the right heart.

Science.gov (United States)

Schneider, Matthias; Binder, Thomas

2018-03-19

Symptoms of right ventricular failure include dyspnea, a reduction in exercise capacity, and fluid retention. Right ventricular (dys)function strongly influences functional state and survival. The right ventricle is directly involved in a variety of diseases. A thorough analysis of right ventricular size and function, as well as estimation of pulmonary artery pressures is an important part of every echocardiographic examination. This review analyses the most commonly used parameters for quantification of right ventricular function. It gives a practical approach for estimation of right ventricular size and function, as well as pulmonary artery pressure.

Echocardiographic findings in haemodialysis patients according to their state of hydration.

Science.gov (United States)

Cristina Di Gioia, María; Gascuena, Raul; Gallar, Paloma; Cobo, Gabriela; Camacho, Rosa; Acosta, Nuria; Baranyi, Zsofia; Rodriguez, Isabel; Oliet, Aniana; Ortega, Olimpia; Fernandez, Inmaculada; Mon, Carmen; Ortiz, Milagros; Manzano, Mari C; Herrero, Juan C; Martinez, José I; Palma, Joaquín; Vigil, Ana

Chronic fluid overload is frequent in hemodialysis patients (P) and it associates with hypertension, left ventricular hypertrophy (LVH) and higher mortality. Moreover, echocardiographic data assessing fluid overload is limited. Our aim was to evaluate the relationship between fluid overload measured by bioimpedance spectroscopy (BIS) and different echocardiographic parameters. Cross-sectional observational study including 76 stable patients. Dry weight was clinically assessed. BIS and echocardiography were performed. Weekly time-averaged fluid overload (TAFO) and relative fluid overload (FO/ECW) were calculated using BIS measurements. Based on TAFO three groups were defined: A- dehydrated, TAFO 1.5 l: 18 (24%). We found significant correlation between TAFO and left atrial volume index (LAVI) (r: 0.29; p=0.013) but not with FO/ECW (r 0.06; p=0.61). TAFO, but not FO/ECW kept a significant relationship with LAVI (p=0.03) using One-Way ANOVA test and linear regression methods. LVH was present in 73.7% (concentric 63.2%, eccentric in 10.5%). No differences between groups in the presence of LVH or left ventricular mass index were found. We found that left atrial volume index determined by echocardiographic Area-length method, but not left ventricle hypertrophy or dimensions of cavities, are related on hydration status based on bioimpedance measured time-averaged fluid overload (TAFO), and not with FO/ECW. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Quantified Facial Soft-tissue Strain in Animation Measured by Real-time Dynamic 3-Dimensional Imaging.

Science.gov (United States)

Hsu, Vivian M; Wes, Ari M; Tahiri, Youssef; Cornman-Homonoff, Joshua; Percec, Ivona

2014-09-01

The aim of this study is to evaluate and quantify dynamic soft-tissue strain in the human face using real-time 3-dimensional imaging technology. Thirteen subjects (8 women, 5 men) between the ages of 18 and 70 were imaged using a dual-camera system and 3-dimensional optical analysis (ARAMIS, Trilion Quality Systems, Pa.). Each subject was imaged at rest and with the following facial expressions: (1) smile, (2) laughter, (3) surprise, (4) anger, (5) grimace, and (6) pursed lips. The facial strains defining stretch and compression were computed for each subject and compared. The areas of greatest strain were localized to the midface and lower face for all expressions. Subjects over the age of 40 had a statistically significant increase in stretch in the perioral region while lip pursing compared with subjects under the age of 40 (58.4% vs 33.8%, P = 0.015). When specific components of lip pursing were analyzed, there was a significantly greater degree of stretch in the nasolabial fold region in subjects over 40 compared with those under 40 (61.6% vs 32.9%, P = 0.007). Furthermore, we observed a greater degree of asymmetry of strain in the nasolabial fold region in the older age group (18.4% vs 5.4%, P = 0.03). This pilot study illustrates that the face can be objectively and quantitatively evaluated using dynamic major strain analysis. The technology of 3-dimensional optical imaging can be used to advance our understanding of facial soft-tissue dynamics and the effects of animation on facial strain over time.

Skin surface and sub-surface strain and deformation imaging using optical coherence tomography and digital image correlation

Science.gov (United States)

Hu, X.; Maiti, R.; Liu, X.; Gerhardt, L. C.; Lee, Z. S.; Byers, R.; Franklin, S. E.; Lewis, R.; Matcher, S. J.; Carré, M. J.

2016-03-01

Bio-mechanical properties of the human skin deformed by external forces at difference skin/material interfaces attract much attention in medical research. For instance, such properties are important design factors when one designs a healthcare device, i.e., the device might be applied directly at skin/device interfaces. In this paper, we investigated the bio-mechanical properties, i.e., surface strain, morphological changes of the skin layers, etc., of the human finger-pad and forearm skin as a function of applied pressure by utilizing two non-invasive techniques, i.e., optical coherence tomography (OCT) and digital image correlation (DIC). Skin deformation results of the human finger-pad and forearm skin were obtained while pressed against a transparent optical glass plate under the action of 0.5-24 N force and stretching naturally from 90° flexion to 180° full extension respectively. The obtained OCT images showed the deformation results beneath the skin surface, however, DIC images gave overall information of strain at the surface.

Exercise-induced changes in left ventricular global longitudinal strain in asymptomatic severe aortic stenosis.

Science.gov (United States)

Lech, Agnieszka K; Dobrowolski, Piotr P; Klisiewicz, Anna; Hoffman, Piotr

2017-01-01

The management of patients with asymptomatic severe aortic stenosis (ASAS) is still under discussion. Therefore, it is advisable to search for the parameters of early damage to left ventricular (LV) function. The aim of the study was to assess exercise-induced changes in LV global longitudinal strain (GLS) in ASAS. The ASAS group consisted of 50 patients (26 women and 24 men, aged 38.4 ± 18.1 years) meeting the echocardiographic criteria of severe aortic stenosis (AVA 4 m/s, mean aortic gradient > 40 mm Hg), with normal LV ejection fraction (LVEF ≥ 55%) and sinus rhythm on electrocardiogram, and without significant concomitant valvular heart diseases. The control group consisted of 21 people matched for age and sex. Echocardiographic examinations and echocardiographic stress tests with the assessment of GLS using the speckle tracking imaging were performed. The ASAS group was characterised by statistically significantly higher LV mass index (LVMI) and higher LVEF. GLS values at rest in both groups were within normal limits but were significantly higher in the control group (-18.9 ± 2.4% vs. -20.7 ± 1.7%, p = 0.006). An increase in GLS at peak exercise in both groups was observed, lower in the ASAS group (the difference was not statistically significant: -0.8 ± 3.0% vs. -2.2 ± 3.1%, p = 0.086). Changes in GLS during exercise (ΔGLS) did not correlate with the parameters of the severity of aortic stenosis. In the multivariate model, LVMI proved to be a factor associated with GLS at rest and during exercise. In patients with ASAS, GLS is a non-invasive marker of an early stage of LV myocardial damage associated with myocardial hypertrophy. An increase in GLS during exercise in the ASAS group, smaller than in the control group, indicates a preserved functional reserve of the LV myocardium but smaller than in healthy individuals. The assessment of the clinical usefulness of exercise-induced changes in GLS requires further research.

Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

Directory of Open Access Journals (Sweden)

Tasso Julio Lobo

2015-01-01

Full Text Available Background: Heart failure and atrial fibrillation (AF often coexist in a deleterious cycle. Objective: To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF ablation. Methods: Patients with ventricular systolic dysfunction [ejection fraction (EF <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class and echocardiographic (EF, left atrial diameter data were compared (McNemar test and t test before and after ablation. Results: 31 patients (6 women, 25 men, aged 37 to 77 years (mean, 59.8±10.6, underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%. During a mean follow-up of 20.3±17 months, 24 patients (77% were in sinus rhythm, 11 (35% being on amiodarone. Eight patients (26% underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures. Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001. The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005 and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026. No major complications occurred. Conclusion: Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement.

Comparison of echocardiographic and cardiac magnetic resonance imaging measurements of functional single ventricular volumes, mass, and ejection fraction (from the Pediatric Heart Network Fontan Cross-Sectional Study).

Science.gov (United States)

Margossian, Renee; Schwartz, Marcy L; Prakash, Ashwin; Wruck, Lisa; Colan, Steven D; Atz, Andrew M; Bradley, Timothy J; Fogel, Mark A; Hurwitz, Lynne M; Marcus, Edward; Powell, Andrew J; Printz, Beth F; Puchalski, Michael D; Rychik, Jack; Shirali, Girish; Williams, Richard; Yoo, Shi-Joon; Geva, Tal

2009-08-01

Assessment of the size and function of a functional single ventricle (FSV) is a key element in the management of patients after the Fontan procedure. Measurement variability of ventricular mass, volume, and ejection fraction (EF) among observers by echocardiography and cardiac magnetic resonance imaging (CMR) and their reproducibility among readers in these patients have not been described. From the 546 patients enrolled in the Pediatric Heart Network Fontan Cross-Sectional Study (mean age 11.9 +/- 3.4 years), 100 echocardiograms and 50 CMR studies were assessed for measurement reproducibility; 124 subjects with paired studies were selected for comparison between modalities. Interobserver agreement for qualitative grading of ventricular function by echocardiography was modest for left ventricular (LV) morphology (kappa = 0.42) and weak for right ventricular (RV) morphology (kappa = 0.12). For quantitative assessment, high intraclass correlation coefficients were found for echocardiographic interobserver agreement (LV 0.87 to 0.92, RV 0.82 to 0.85) of systolic and diastolic volumes, respectively. In contrast, intraclass correlation coefficients for LV and RV mass were moderate (LV 0.78, RV 0.72). The corresponding intraclass correlation coefficients by CMR were high (LV 0.96, RV 0.85). Volumes by echocardiography averaged 70% of CMR values. Interobserver reproducibility for the EF was similar for the 2 modalities. Although the absolute mean difference between modalities for the EF was small (<2%), 95% limits of agreement were wide. In conclusion, agreement between observers of qualitative FSV function by echocardiography is modest. Measurements of FSV volume by 2-dimensional echocardiography underestimate CMR measurements, but their reproducibility is high. Echocardiographic and CMR measurements of FSV EF demonstrate similar interobserver reproducibility, whereas measurements of FSV mass and LV diastolic volume are more reproducible by CMR.

Left ventricular strain and strain rate by 2D speckle tracking in chronic thromboembolic pulmonary hypertension before and after pulmonary thromboendarterectomy

Directory of Open Access Journals (Sweden)

Waltman Thomas J

2010-09-01

Full Text Available Abstract Background Echocardiographic evaluation of left ventricular (LV strain and strain rate (SR by 2D speckle tracking may be useful tools to assess chronic thromboembolic pulmonary hypertension (CTEPH severity as well as response to successful pulmonary thromboendarterectomy (PTE. Methods We evaluated 30 patients with CTEPH before and after PTE using 2D speckle tracking measurements of LV radial and circumferential strain and SR in the short axis, and correlated the data with right heart catheterization (RHC. Results PTE resulted in a decrease in mean PA pressure (44 ± 15 to 29 ± 9 mmHg, decrease in PVR (950 ± 550 to 31 ± 160 [dyne-sec]/cm5, and an increase in cardiac output (3.9 ± 1.0 to 5.0 ± 1.0 L/min, p change in circumferential strain and change in posterior wall radial strain correlated moderately well with changes in PVR, mean PA pressure and cardiac output (r = 0.69, 0.76, and 0.51 for circumferential strain [p Conclusions LV circumferential and posterior wall radial strain change after relief of pulmonary arterial obstruction in patients with CTEPH, and these improvements occur rapidly. These changes in LV strain may reflect effects from improved LV diastolic filling, and may be useful non-invasive markers of successful PTE.

Clinical Outcome of Degenerative Mitral Regurgitation: Critical Importance of Echocardiographic Quantitative Assessment in Routine Practice.

Science.gov (United States)

Antoine, Clemence; Benfari, Giovanni; Michelena, Hector I; Malouf, Joseph F; Nkomo, Vuyisile T; Thapa, Prabin; Enriquez-Sarano, Maurice

2018-05-31

Background -Echocardiographic quantitation of degenerative mitral regurgitation (DMR) is recommended whenever possible in clinical guidelines but is criticized and its scalability to routine clinical practice doubted. We hypothesized that echocardiographic DMR quantitation, performed in routine clinical practice by multiple practitioners predicts independently long-term survival, and thus is essential to DMR management. Methods -We included patients diagnosed with isolated mitral-valve-prolapse 2003-2011 and any degree of MR quantified by any physician/sonographer in routine clinical practice. Clinical/echocardiographic data acquired at diagnosis were retrieved electronically. Endpoint was mortality under medical treatment analyzed by Kaplan-Meir method and Proportional-Hazard models. Results -The cohort included 3914 patients (55% male) aged 62±17 years, with left ventricular ejection fraction (LVEF) 63±8% and routinely measured effective regurgitant orifice area (EROA) 19[0-40] mm 2 During follow-up (6.7±3.1 years) 696 patients died under medical management and 1263 underwent mitral surgery. In multivariate analysis, routinely measured EROA was associated with mortality (adjusted-hazard-ratio 1.19[1.13-1.24] p 40 mm 2 threshold. Conclusions -Echocardiographic DMR quantitation is scalable to routine practice and is independently associated with clinical outcome. Routinely measured EROA is strongly associated with long-term survival under medical treatment. Excess mortality vs. the general population appears in the "moderate" DMR range and steadily increases with higher EROA. Hence, individual EROA values should be integrated into therapeutic considerations, additionally to categorical DMR grading.

Making three-dimensional echocardiography more tangible: a workflow for three-dimensional printing with echocardiographic data

Directory of Open Access Journals (Sweden)

Azad Mashari MD

2016-12-01

Full Text Available Three-dimensional (3D printing is a rapidly evolving technology with several potential applications in the diagnosis and management of cardiac disease. Recently, 3D printing (i.e. rapid prototyping derived from 3D transesophageal echocardiography (TEE has become possible. Due to the multiple steps involved and the specific equipment required for each step, it might be difficult to start implementing echocardiography-derived 3D printing in a clinical setting. In this review, we provide an overview of this process, including its logistics and organization of tools and materials, 3D TEE image acquisition strategies, data export, format conversion, segmentation, and printing. Generation of patient-specific models of cardiac anatomy from echocardiographic data is a feasible, practical application of 3D printing technology.

Echocardiographic findings in haemodialysis patients according to their state of hydration

Directory of Open Access Journals (Sweden)

María Cristina Di Gioia

2017-01-01

Conclusions: We found that left atrial volume index determined by echocardiographic Area-length method, but not left ventricle hypertrophy or dimensions of cavities, are related on hydration status based on bioimpedance measured time-averaged fluid overload (TAFO, and not with FO/ECW.

Myocardial multilayer strain does not provide additional value for detection of myocardial viability assessed by SPECT imaging over and beyond standard strain.

Science.gov (United States)

Orloff, Elisabeth; Fournier, Pauline; Bouisset, Frédéric; Moine, Thomas; Cournot, Maxime; Elbaz, Meyer; Carrié, Didier; Galinier, Michel; Lairez, Olivier; Cognet, Thomas

2018-05-14

The aim of this study was to evaluate the value of multilayer strain analysis to the assessment of myocardial viability (MV) through the comparison of both speckle tracking echocardiography and single-photon emission computed tomography (SPECT) imaging. We also intended to determine which segmental longitudinal strain (LS) cutoff value would be optimal to discriminate viable myocardium. We included 47 patients (average age: 61 ± 11 years) referred to our cardiac imaging center for MV evaluation. All patients underwent transthoracic echocardiography with measures of LS, SPECT, and coronary angiography. In all, 799 segments were analyzed. We correlated myocardial tracer uptake by SPECT with sub-endocardial, sub-epicardial, and mid-segmental LS values with r = .514 P Multilayer strain analysis does not evaluate MV with more accuracy than standard segmental LS analysis. © 2018 Wiley Periodicals, Inc.

In situ study of annealing-induced strain relaxation in diamond nanoparticles using Bragg coherent diffraction imaging

Directory of Open Access Journals (Sweden)

S. O. Hruszkewycz

2017-02-01

Full Text Available We observed changes in morphology and internal strain state of commercial diamond nanocrystals during high-temperature annealing. Three nanodiamonds were measured with Bragg coherent x-ray diffraction imaging, yielding three-dimensional strain-sensitive images as a function of time/temperature. Up to temperatures of 800 °C, crystals with Gaussian strain distributions with a full-width-at-half-maximum of less than 8×10−4 were largely unchanged, and annealing-induced strain relaxation was observed in a nanodiamond with maximum lattice distortions above this threshold. X-ray measurements found changes in nanodiamond morphology at temperatures above 600 °C that are consistent with graphitization of the surface, a result verified with ensemble Raman measurements.

Long-term follow-up in repaired tetralogy of fallot: can deformation imaging help identify optimal timing of pulmonary valve replacement?

Science.gov (United States)

Sabate Rotes, Anna; Bonnichsen, Crystal R; Reece, Chelsea L; Connolly, Heidi M; Burkhart, Harold M; Dearani, Joseph A; Eidem, Benjamin W

2014-12-01

Novel echocardiographic techniques based on myocardial deformation have not been extensively evaluated to assess right ventricular (RV) and left ventricular (LV) response after pulmonary valve replacement (PVR) in patients with repaired tetralogy of Fallot. Between 2003 and 2012, 133 patients undergoing first-time PVR after tetralogy of Fallot repair underwent echocardiographic assessment at Mayo Clinic. The last echocardiogram before PVR and 1 year after surgery were retrospectively analyzed with Velocity Vector Imaging. Mean age at PVR was 35.5 ± 16.2 years (54% women). Longitudinal peak systolic strain and strain rate before PVR were low: for the left ventricle, -14.8 ± 3.5% and -0.8 ± 0.2 sec(-1), and for the right ventricle, -16.2 ± 4.1% and -0.9 ± 0.3 sec(-1), respectively. There was no significant change in either parameter after surgery. A close correlation between LV and RV deformational parameters was found before PVR and was maintained after surgery. In the multivariate analysis, patients with better LV and RV peak systolic strain preoperatively were found to have better LV and RV peak systolic strain after surgery (P = .004 and P = .006, respectively). However, patients with the most improvement in deformation were those with worse RV function preoperatively (P = .002). Mean New York Heart Association class at early follow-up improved from 2.2 ± 0.8 to 1.2 ± 0.6 (P tetralogy of Fallot undergoing PVR, and there was no significant change after surgery. However, preoperative systolic deformational parameters were predictive of postoperative ventricular function and New York Heart Association class after PVR and may be helpful to identify optimal timing for surgical intervention in this cohort. Copyright © 2014 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

"Porcelain heart" cardiomyopathy secondary to hyperparathyroidism: radiographic, echocardiographic, and cardiac CT appearances.

LENUS (Irish Health Repository)

Freeman, James

2012-02-01

We report the radiographic, echocardiographic and cardiac CT appearances of \\'porcelain heart\\' in an 85-year-old woman who presented with progressive heart failure. The extensive myocardial calcification was secondary to hyperparathyroidism with renal failure.

"Porcelain heart" cardiomyopathy secondary to hyperparathyroidism: radiographic, echocardiographic, and cardiac CT appearances.

LENUS (Irish Health Repository)

Freeman, James

2010-11-01

We report the radiographic, echocardiographic and cardiac CT appearances of \\'porcelain heart\\' in an 85-year-old woman who presented with progressive heart failure. The extensive myocardial calcification was secondary to hyperparathyroidism with renal failure.

Myocardial strains from 3D displacement encoded magnetic resonance imaging

International Nuclear Information System (INIS)

Kindberg, Katarina; Haraldsson, Henrik; Sigfridsson, Andreas; Engvall, Jan; Ingels, Neil B Jr; Ebbers, Tino; Karlsson, Matts

2012-01-01

The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts

Views of physicians in training on the ethical and legal issues in preliminary reporting of echocardiographic data.

Science.gov (United States)

McDonald, R W; Rice, M J; Marcella, C P; Reller, M D; Imus, R L

1991-01-01

Cardiac sonographers may be pressured by physicians into giving diagnostic interpretations of echocardiographic data. This study investigated the issue of preliminary reporting of echocardiographic data. A questionnaire was sent to 292 physicians; 85 physicians (29%) responded. Seventy-two physicians (87%) thought they had more than a minimal knowledge of echocardiography, 94% wanted a written or verbal preliminary report, and 84% thought that giving a preliminary report should be part of the cardiac sonographer's job. If abnormalities were found, 80% wanted the results before a cardiologist reviewed the study, and 56% would want a diagnostic rather than a descriptive report. Fifty-four physicians (64%) would pressure the cardiac sonographer into giving a preliminary echocardiographic report and would use this information to manage the patient. The majority of the physicians thought that it is legal for the cardiac sonographer to give a preliminary echocardiogram report. Eighty percent said that the cardiac sonographer would not be "practicing medicine without a license," and 82% that the sonographer would not be "aiding and abetting the unauthorized practice of medicine." This data would indicate that physicians at Oregon Health Sciences University want the cardiac sonographer to give preliminary echocardiographic results, even though the sonographer may be breaking state statutes.

New strain measurement method at axial tensile test of thin films through direct imaging

Energy Technology Data Exchange (ETDEWEB)

Ha, Jong-Eun [Department of Automotive Engineering, Seoul National Uinversity of Technolgy, 172 Gongneung-2 Dong, Nowon-Gu, Seoul (Korea, Republic of); Park, Jun-Hyub [Department of Mechatronics Engineering, College of Engineering, Tongmyong University, 535, Yongdang-Dong, Nam-Gu, Busan 608-711 (Korea, Republic of); Kang, Dong-Joong [School of Mechanical Eng., Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)], E-mail: jhyubpark@korea.com

2008-09-07

This paper proposes a new method for measuring strain during a tensile test of the specimen with micrometre size through direct imaging. A specimen was newly designed for adoption of direct imaging which was the main contribution of the proposed system. The structure of the specimen has eight indicators that make it possible to adopt direct imaging and it is fabricated using the same process of microelectromechanical system (MEMS) devices to guarantee the feasibility of the tensile test. We implemented a system for non-contact in situ measurement of strain with the specimen, the image-based displacement measurement system. Extension of the gauge length in the specimen could be found robustly by computing the positions of the eight rectangular-shape indicators on the image. Also, for an easy setup procedure, the region of interest was found automatically through the analysis of the edge projection profile along the horizontal direction. To gain confidence in the reliability of the system, the tensile test for the Al-3%Ti thin film was performed, which is widely used as a material in MEMS devices. Tensile tests were performed and displacements were measured using the proposed method and also the capacitance type displacement sensor for comparison. It is demonstrated that the new strain measurement system can be effectively used in the tensile test of the specimen at microscale with easy setup and better accuracy.

Intra-operative ultrasound hand-held strain imaging for the visualization of ablations produced in the liver with a toroidal HIFU transducer: first in vivo results

Energy Technology Data Exchange (ETDEWEB)

Chenot, J; Melodelima, D; N' Djin, W A; Souchon, Remi; Rivoire, M; Chapelon, J Y, E-mail: jeremy.chenot@inserm.f [Inserm, U556, Lyon, F-69003 (France)

2010-06-07

The use of hand-held ultrasound strain imaging for the intra-operative real-time visualization of HIFU (high-intensity focused ultrasound) ablations produced in the liver by a toroidal transducer was investigated. A linear 12 MHz ultrasound imaging probe was used to obtain radiofrequency signals. Using a fast cross-correlation algorithm, strain images were calculated and displayed at 60 frames s{sup -1}, allowing the use of hand-held strain imaging intra-operatively. Fourteen HIFU lesions were produced in four pigs. Intra-operative strain imaging of HIFU ablations in the liver was feasible owing to the high frame rate. The correlation between dimensions measured on gross pathology and dimensions measured on B-mode images and on strain images were R = 0.72 and R = 0.94 respectively. The contrast between ablated and non-ablated tissue was significantly higher (p < 0.05) in the strain images (22 dB) than in the B-mode images (9 dB). Strain images allowed equivalent or improved definition of ablated regions when compared with B-mode images. Real-time intra-operative hand-held strain imaging seems to be a promising complement to conventional B-mode imaging for the guidance of HIFU ablations produced in the liver during an open procedure. These results support that hand-held strain imaging outperforms conventional B-mode ultrasound and could potentially be used for the assessment of thermal therapies.

Quantitative Imaging of the Stress/Strain Fields and Generation of Macroscopic Cracks from Indents in Silicon

Directory of Open Access Journals (Sweden)

Brian K. Tanner

2017-11-01

Full Text Available The crack geometry and associated strain field around Berkovich and Vickers indents on silicon have been studied by X-ray diffraction imaging and micro-Raman spectroscopy scanning. The techniques are complementary; the Raman data come from within a few micrometres of the indentation, whereas the X-ray image probes the strain field at a distance of typically tens of micrometres. For example, Raman data provide an explanation for the central contrast feature in the X-ray images of an indent. Strain relaxation from breakout and high temperature annealing are examined and it is demonstrated that millimetre length cracks, similar to those produced by mechanical damage from misaligned handling tools, can be generated in a controlled fashion by indentation within 75 micrometres of the bevel edge of 200 mm diameter wafers.

A three-dimensional strain measurement method in elastic transparent materials using tomographic particle image velocimetry.

Directory of Open Access Journals (Sweden)

Azuma Takahashi

Full Text Available The mechanical interaction between blood vessels and medical devices can induce strains in these vessels. Measuring and understanding these strains is necessary to identify the causes of vascular complications. This study develops a method to measure the three-dimensional (3D distribution of strain using tomographic particle image velocimetry (Tomo-PIV and compares the measurement accuracy with the gauge strain in tensile tests.The test system for measuring 3D strain distribution consists of two cameras, a laser, a universal testing machine, an acrylic chamber with a glycerol water solution for adjusting the refractive index with the silicone, and dumbbell-shaped specimens mixed with fluorescent tracer particles. 3D images of the particles were reconstructed from 2D images using a multiplicative algebraic reconstruction technique (MART and motion tracking enhancement. Distributions of the 3D displacements were calculated using a digital volume correlation. To evaluate the accuracy of the measurement method in terms of particle density and interrogation voxel size, the gauge strain and one of the two cameras for Tomo-PIV were used as a video-extensometer in the tensile test. The results show that the optimal particle density and interrogation voxel size are 0.014 particles per pixel and 40 × 40 × 40 voxels with a 75% overlap. The maximum measurement error was maintained at less than 2.5% in the 4-mm-wide region of the specimen.We successfully developed a method to experimentally measure 3D strain distribution in an elastic silicone material using Tomo-PIV and fluorescent particles. To the best of our knowledge, this is the first report that applies Tomo-PIV to investigate 3D strain measurements in elastic materials with large deformation and validates the measurement accuracy.

Full 3D internal strain measurement for device packaging materials using synchrotron laminography and volumetric digital image correlation method

International Nuclear Information System (INIS)

Asada, Takashi; Kimura, Hidehiko; Yamaguchi, Satoshi; Kano, Taiki; Kajiwara, Kentaro

2014-01-01

In order to measure full 3D internal strain field of resin molding compound specimens, synchrotron computed tomography and laminography at SPring-8 were performed. Then the reconstructed images were applied to 3D digital image correlation method to compute internal strain field. The results showed that internal strains in resin molding compound could be visualized in this way. (author)

Myocardial strains from 3D displacement encoded magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Kindberg Katarina

2012-04-01

Full Text Available Abstract Background The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE, make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. Methods We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. Results The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Conclusions Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

Echocardiographic study of the cardiac state in systemic scleroderma

International Nuclear Information System (INIS)

Kotel'nikova, G.P.; Guseva, N.G.

1986-01-01

Echocardiographic investigation in 65 patients with systemic scleroderma showed that the left ventricular syes and indices of central hemodynamics were frequently lowered in them; an increase in sizes was observed mainly in the patients with stage 2-3 of disease. Echocardiography made it possible to specify the nature of cardiac pathology and brought to light some additional features of the involvement of different heart membranes in systemic scleroderma

Optimizing structure in nanodiamonds using in-situ strain-sensitive Bragg coherent diffraction imaging.

Science.gov (United States)

Hruszkewycz, Stephan; Cha, Wonsuk; Ulvestad, Andrew; Fuoss, Paul; Heremans, F. Joseph; Harder, Ross; Andrich, Paolo; Anderson, Christopher; Awschalom, David

The nitrogen-vacancy center in diamond has attracted considerable attention for nanoscale sensing due to unique optical and spin properties. Many of these applications require diamond nanoparticles which contain large amounts of residual strain due to the detonation or milling process used in their fabrication. Here, we present experimental, in-situ observations of changes in morphology and internal strain state of commercial nanodiamonds during high-temperature annealing using Bragg coherent diffraction imaging to reconstruct a strain-sensitive 3D image of individual sub-micron-sized crystals. We find minimal structural changes to the nanodiamonds at temperatures less than 650 C, and that at higher temperatures up to 750 C, the diamond-structured volume fraction of nanocrystals tend to shrink. The degree of internal lattice distortions within nanodiamond particles also decreases during the anneal. Our findings potentially enable the design of efficient processing of commercial nanodiamonds into viable materials suitable for device design. We acknowledge support from U.S. DOE, Office of Science, BES, MSE.

Evaluation of ventricular dysfunction using semi-automatic longitudinal strain analysis of four-chamber cine MR imaging.

Science.gov (United States)

Kawakubo, Masateru; Nagao, Michinobu; Kumazawa, Seiji; Yamasaki, Yuzo; Chishaki, Akiko S; Nakamura, Yasuhiko; Honda, Hiroshi; Morishita, Junji

2016-02-01

The aim of this study was to evaluate ventricular dysfunction using the longitudinal strain analysis in 4-chamber (4CH) cine MR imaging, and to investigate the agreement between the semi-automatic and manual measurements in the analysis. Fifty-two consecutive patients with ischemic, or non-ischemic cardiomyopathy and repaired tetralogy of Fallot who underwent cardiac MR examination incorporating cine MR imaging were retrospectively enrolled. The LV and RV longitudinal strain values were obtained by semi-automatically and manually. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff of the minimum longitudinal strain value for the detection of patients with cardiac dysfunction. The correlations between manual and semi-automatic measurements for LV and RV walls were analyzed by Pearson coefficient analysis. ROC analysis demonstrated the optimal cut-off of the minimum longitudinal strain values (εL_min) for diagnoses the LV and RV dysfunction at a high accuracy (LV εL_min = -7.8 %: area under the curve, 0.89; sensitivity, 83 %; specificity, 91 %, RV εL_min = -15.7 %: area under the curve, 0.82; sensitivity, 92 %; specificity, 68 %). Excellent correlations between manual and semi-automatic measurements for LV and RV free wall were observed (LV, r = 0.97, p cine MR imaging can evaluate LV and RV dysfunction with simply and easy measurements. The strain analysis could have extensive application in cardiac imaging for various clinical cases.

Echocardiographic indexes help predict the need for nuclear magnetic resonance evaluation of patients with repaired Tetralogy of Fallot

International Nuclear Information System (INIS)

Ferreiro, Myriam; Toro, Lida; Andia, Marcelo; Zelada, Pamela; Alcantara, Alex; Castillo, Maria Elisa; Lagos, Rosa; Bareno, Sandra; Uribe, Sergio

2013-01-01

Background: Pulmonary insufficiency (PI) frequently appears long-term after repair of Tetralogy of Fallot (TOFr). Cardiac magnetic resonance (CMR) plays a fundamental role in the indication of pulmonary valve replacement, in order to avoid complications of PI. However, CMR is a scarce and expensive resource in our reality, which is why its indication must be optimized. Aim: The objective of this work is to find echocardiographic indices to identify patients with TOFr with dilated RV and reduced ejection fraction (EF) Method: Images from echocardiograms (ECHO) and CMR in 20 patients (9 women, 8-25 years of age, average 15,8 years old) with TOFr were retrospectively reviewed. From ECHO images we obtained measurements for tricuspid annular plane systolic excursion (TAPSE), tissular s wave, isovolumetric acceleration (IVA), and severity of PI (mild, moderate, or severe). From CMR images, we measured EF, end diastolic volume (EDV) of the RV, and regurgitant fraction (RF) of the pulmonary artery. We performed a multivariate statistical analysis to explore the relation between ECHO parameters and CMR findings Results: No correlation was found between individual ECHO parameters and EDV or RV EF. However, we did find a model based on the TAPSE and PI that was able to predict the EDV of the RV with an r2 = 0.6. (FDV-RV = 8.60*TAPSE + 36.19*PI - 77.213). After comparing the PI with RF, we found that that echocardiography could correctly distinguish cases with mild PI from those with severe PI (p<0.001), or moderate from severe (p=0.004), but not mild from moderate PI Conclusion: In this preliminary study, we found a statistical model based on the TAPSE and PI which could be useful in the selection of patients with TOFr that are referred to CMR. While this study needs to be validated on a greater number of patients, it indicates the relevance of some echocardiographic parameters, which should always be included in the evaluation of patients with TOFr

Utilization of a pressure sensor guidewire to measure bileaflet mechanical valve gradients: hemodynamic and echocardiographic sequelae.

Science.gov (United States)

Doorey, Andrew J; Gakhal, Mandip; Pasquale, Michael J

2006-04-01

Suspected prosthetic valve dysfunction is a difficult clinical problem, because of the high risk of repeat valvular surgery. Echocardiographic measurements of prosthetic valvular dysfunction can be misleading, especially with bileaflet valves. Direct measurement of trans-valvular gradients is problematic because of potentially serious catheter entrapment issues. We report a case in which a high-fidelity pressure sensor angioplasty guidewire was used to cross prosthetic mitral and aortic valves in a patient, with hemodynamic and echocardiographic assessment. This technique was safe and effective, refuting the inaccurate non-invasive tests that over-estimated the aortic valvular gradient.

3D echocardiographic analysis of aortic annulus for transcatheter aortic valve replacement using novel aortic valve quantification software: Comparison with computed tomography.

Science.gov (United States)

Mediratta, Anuj; Addetia, Karima; Medvedofsky, Diego; Schneider, Robert J; Kruse, Eric; Shah, Atman P; Nathan, Sandeep; Paul, Jonathan D; Blair, John E; Ota, Takeyoshi; Balkhy, Husam H; Patel, Amit R; Mor-Avi, Victor; Lang, Roberto M

2017-05-01

With the increasing use of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis (AS), computed tomography (CT) remains the standard for annulus sizing. However, 3D transesophageal echocardiography (TEE) has been an alternative in patients with contraindications to CT. We sought to (1) test the feasibility, accuracy, and reproducibility of prototype 3DTEE analysis software (Philips) for aortic annular measurements and (2) compare the new approach to the existing echocardiographic techniques. We prospectively studied 52 patients who underwent gated contrast CT, procedural 3DTEE, and TAVR. 3DTEE images were analyzed using novel semi-automated software designed for 3D measurements of the aortic root, which uses multiplanar reconstruction, similar to CT analysis. Aortic annulus measurements included area, perimeter, and diameter calculations from these measurements. The results were compared to CT-derived values. Additionally, 3D echocardiographic measurements (3D planimetry and mitral valve analysis software adapted for the aortic valve) were also compared to the CT reference values. 3DTEE image quality was sufficient in 90% of patients for aortic annulus measurements using the new software, which were in good agreement with CT (r-values: .89-.91) and small (software can accurately measure aortic annulus in patients with severe AS undergoing TAVR, in better agreement with CT than the existing methodology. Accordingly, intra-procedural TEE could potentially replace CT in patients where CT carries significant risk. © 2017, Wiley Periodicals, Inc.

Comparison of plastic strains on AA5052 by single point incremental forming process using digital image processing

International Nuclear Information System (INIS)

Mugendiran, V.; Gnanavelbabu, A.

2017-01-01

In this study, a surface based strain measurement was used to determine the formability of the sheet metal. A strain measurement may employ manual calculation of plastic strains based on the reference circle and the deformed circle. The manual calculation method has a greater margin of error in the practical applications. In this paper, an attempt has been made to compare the formability by implementing three different theoretical approaches: Namely conventional method, least square method and digital based strain measurements. As the sheet metal was formed by a single point incremental process the etched circles get deformed into elliptical shapes approximately, image acquisition has been done before and after forming. The plastic strains of the deformed circle grids are calculated based on the non- deformed reference. The coordinates of the deformed circles are measured by various image processing steps. Finally the strains obtained from the deformed circle are used to plot the forming limit diagram. To evaluate the accuracy of the system, the conventional, least square and digital based method of prediction of the forming limit diagram was compared. Conventional method and least square method have marginal error when compared with digital based processing method. Measurement of strain based on image processing agrees well and can be used to improve the accuracy and to reduce the measurement error in prediction of forming limit diagram.

Comparison of plastic strains on AA5052 by single point incremental forming process using digital image processing

Energy Technology Data Exchange (ETDEWEB)

Mugendiran, V.; Gnanavelbabu, A. [Anna University, Chennai, Tamilnadu (India)

2017-06-15

In this study, a surface based strain measurement was used to determine the formability of the sheet metal. A strain measurement may employ manual calculation of plastic strains based on the reference circle and the deformed circle. The manual calculation method has a greater margin of error in the practical applications. In this paper, an attempt has been made to compare the formability by implementing three different theoretical approaches: Namely conventional method, least square method and digital based strain measurements. As the sheet metal was formed by a single point incremental process the etched circles get deformed into elliptical shapes approximately, image acquisition has been done before and after forming. The plastic strains of the deformed circle grids are calculated based on the non- deformed reference. The coordinates of the deformed circles are measured by various image processing steps. Finally the strains obtained from the deformed circle are used to plot the forming limit diagram. To evaluate the accuracy of the system, the conventional, least square and digital based method of prediction of the forming limit diagram was compared. Conventional method and least square method have marginal error when compared with digital based processing method. Measurement of strain based on image processing agrees well and can be used to improve the accuracy and to reduce the measurement error in prediction of forming limit diagram.

Lattice and strain analysis of atomic resolution Z-contrast images based on template matching

Energy Technology Data Exchange (ETDEWEB)

Zuo, Jian-Min, E-mail: jianzuo@uiuc.edu [Department of Materials Science and Engineering, University of Illinois, Urbana, IL 61801 (United States); Seitz Materials Research Laboratory, University of Illinois, Urbana, IL 61801 (United States); Shah, Amish B. [Center for Microanalysis of Materials, Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Kim, Honggyu; Meng, Yifei; Gao, Wenpei [Department of Materials Science and Engineering, University of Illinois, Urbana, IL 61801 (United States); Seitz Materials Research Laboratory, University of Illinois, Urbana, IL 61801 (United States); Rouviére, Jean-Luc [CEA-INAC/UJF-Grenoble UMR-E, SP2M, LEMMA, Minatec, Grenoble 38054 (France)

2014-01-15

A real space approach is developed based on template matching for quantitative lattice analysis using atomic resolution Z-contrast images. The method, called TeMA, uses the template of an atomic column, or a group of atomic columns, to transform the image into a lattice of correlation peaks. This is helped by using a local intensity adjusted correlation and by the design of templates. Lattice analysis is performed on the correlation peaks. A reference lattice is used to correct for scan noise and scan distortions in the recorded images. Using these methods, we demonstrate that a precision of few picometers is achievable in lattice measurement using aberration corrected Z-contrast images. For application, we apply the methods to strain analysis of a molecular beam epitaxy (MBE) grown LaMnO{sub 3} and SrMnO{sub 3} superlattice. The results show alternating epitaxial strain inside the superlattice and its variations across interfaces at the spatial resolution of a single perovskite unit cell. Our methods are general, model free and provide high spatial resolution for lattice analysis. - Highlights: • A real space approach is developed for strain analysis using atomic resolution Z-contrast images and template matching. • A precision of few picometers is achievable in the measurement of lattice displacements. • The spatial resolution of a single perovskite unit cell is demonstrated for a LaMnO{sub 3} and SrMnO{sub 3} superlattice grown by MBE.

Strain measurement of objects subjected to aerodynamic heating using digital image correlation: experimental design and preliminary results.

Science.gov (United States)

Pan, Bing; Jiang, Tianyun; Wu, Dafang

2014-11-01

In thermomechanical testing of hypersonic materials and structures, direct observation and quantitative strain measurement of the front surface of a test specimen directly exposed to severe aerodynamic heating has been considered as a very challenging task. In this work, a novel quartz infrared heating device with an observation window is designed to reproduce the transient thermal environment experienced by hypersonic vehicles. The specially designed experimental system allows the capture of test article's surface images at various temperatures using an optical system outfitted with a bandpass filter. The captured images are post-processed by digital image correlation to extract full-field thermal deformation. To verify the viability and accuracy of the established system, thermal strains of a chromiumnickel austenite stainless steel sample heated from room temperature up to 600 °C were determined. The preliminary results indicate that the air disturbance between the camera and the specimen due to heat haze induces apparent distortions in the recorded images and large errors in the measured strains, but the average values of the measured strains are accurate enough. Limitations and further improvements of the proposed technique are discussed.

A Cognitive Machine Learning Algorithm for Cardiac Imaging: A Pilot Study for Differentiating Constrictive Pericarditis from Restrictive Cardiomyopathy

Science.gov (United States)

Sengupta, Partho P.; Huang, Yen-Min; Bansal, Manish; Ashrafi, Ali; Fisher, Matt; Shameer, Khader; Gall, Walt; Dudley, Joel T

2016-01-01

Background Associating a patient’s profile with the memories of prototypical patients built through previous repeat clinical experience is a key process in clinical judgment. We hypothesized that a similar process using a cognitive computing tool would be well suited for learning and recalling multidimensional attributes of speckle tracking echocardiography (STE) data sets derived from patients with known constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM). Methods and Results Clinical and echocardiographic data of 50 patients with CP and 44 with RCM were used for developing an associative memory classifier (AMC) based machine learning algorithm. The STE data was normalized in reference to 47 controls with no structural heart disease, and the diagnostic area under the receiver operating characteristic curve (AUC) of the AMC was evaluated for differentiating CP from RCM. Using only STE variables, AMC achieved a diagnostic AUC of 89·2%, which improved to 96·2% with addition of 4 echocardiographic variables. In comparison, the AUC of early diastolic mitral annular velocity and left ventricular longitudinal strain were 82.1% and 63·7%, respectively. Furthermore, AMC demonstrated greater accuracy and shorter learning curves than other machine learning approaches with accuracy asymptotically approaching 90% after a training fraction of 0·3 and remaining flat at higher training fractions. Conclusions This study demonstrates feasibility of a cognitive machine learning approach for learning and recalling patterns observed during echocardiographic evaluations. Incorporation of machine learning algorithms in cardiac imaging may aid standardized assessments and support the quality of interpretations, particularly for novice readers with limited experience. PMID:27266599

Power of resting echocardiographic measurements to classify pulmonary hypertension patients according to European society of cardiology exercise testing risk stratification cut-offs.

Science.gov (United States)

Rehman, Michaela B; Garcia, Rodrigue; Christiaens, Luc; Larrieu-Ardilouze, Elisa; Howard, Luke S; Nihoyannopoulos, Petros

2018-04-15

Right ventricular function is the major determinant of morbidity and mortality in pulmonary arterial hypertension (PAH). The ESC risk assessment strategy for PAH is based on clinical status, exercise testing, NTproBNP, imaging and haemodynamics but does not include right ventricular function. Our aims were to test the power of resting echocardiographic measurements to classify PAH patients according to ESC exercise testing risk stratification cut-offs and to determine if the classification power of echocardiographic parameters varied in chronic thrombo-embolic pulmonary hypertension (CTEPH). We prospectively and consecutively recruited 46 PAH patients and 42 CTEPH patients referred for cardio-pulmonary exercise testing and comprehensive transthoracic echocardiography. Exercise testing parameters analyzed were peak oxygen consumption, percentage of predicted maximal oxygen consumption and the slope of ventilation against carbon dioxide production. Receiver operator characteristic curves were used to determine the optimal diagnostic cut-off values of echocardiographic parameters for classifying the patients in intermediate or high risk category according to exercise testing. Measurements of right ventricular systolic function were the best for classifying in PAH (area under the curve 0.815 to 0.935). Measurements of right ventricular pressure overload (0.810 to 0.909) were optimal for classifying according to exercise testing in CTEPH. Measurements of left ventricular function were of no use in either group. Measurements of right ventricular systolic function can classify according to exercise testing risk stratification cut-offs in PAH. However, this is not the case in CTEPH where pressure overload, rather than right ventricular function seems to be linked to exercise performance. Copyright © 2018 Elsevier B.V. All rights reserved.

Quantified Facial Soft-tissue Strain in Animation Measured by Real-time Dynamic 3-Dimensional Imaging

Directory of Open Access Journals (Sweden)

Vivian M. Hsu, MD

2014-09-01

Conclusions: This pilot study illustrates that the face can be objectively and quantitatively evaluated using dynamic major strain analysis. The technology of 3-dimensional optical imaging can be used to advance our understanding of facial soft-tissue dynamics and the effects of animation on facial strain over time.

Combined Synchrotron X-ray Diffraction and Digital Image Correlation Technique for Measurement of Austenite Transformation with Strain in TRIP-assisted Steels

Energy Technology Data Exchange (ETDEWEB)

Poling, Whitney A.; Savic, Vesna; Hector, Louis G.; Sachdev, Anil K.; Hu, Xiaohua; Devaraj, Arun; Abu-Farha, Fadi

2016-04-05

The strain-induced, diffusionless shear transformation of retained austenite to martensite during straining of transformation induced plasticity (TRIP) assisted steels increases strain hardening and delays necking and fracture leading to exceptional ductility and strength, which are attractive for automotive applications. A novel technique that provides the retained austenite volume fraction variation with strain in TRIP-assisted steels with improved precision is presented. Digital images of the gauge section of tensile specimens were first recorded up to selected plastic strains with a stereo digital image correlation (DIC) system. The austenite volume fraction was measured by synchrotron X-ray diffraction from small squares cut from the gage section. Strain fields in the squares were then computed by localizing the strain measurement to the corresponding region of a given square during DIC post-processing of the images recorded during tensile testing. Results obtained for a QP980 steel are used to study the influence of initial volume fraction of austenite and the austenite transformation with strain on tensile mechanical behavior.

NT-proBNP, echocardiographic abnormalities and subclinical coronary artery disease in high risk type 2 diabetic patients

DEFF Research Database (Denmark)

Reinhard, Henrik; Hansen, Peter R; Wiinberg, Niels

2012-01-01

-NT-proBNP and the putative residual abnormalities in such patients are not well described. This study examined echocardiographic measurements of LV hypertrophy, atrial dilatation and LV dysfunction and their relation to P-NT-proBNP levels or subclinical coronary artery disease (CAD) in type 2 diabetic patients......Intensive multifactorial treatment aimed at prevention of cardiovascular (CV) disease may reduce left ventricular (LV) echocardiographic abnormalities in diabetic subjects. Plasma N-terminal (NT)-proBNP predicts CV mortality in diabetic patients but the association between P...

Doppler echocardiographic predictors of mortality in female rats after myocardial infarction.

Science.gov (United States)

Santos, Alexandra Alberta; Helber, Izzo; Flumignan, Ronald L G; Antonio, Ednei L; Carvalho, Antonio C; Paola, Angelo A; Tucci, Paulo J; Moises, Valdir A

2009-03-01

Doppler echocardiogram is useful for the evaluation of anatomical and functional changes in late myocardial infarction (MI) in rats. However, no studies have evaluated the prognostic value of echocardiographic parameters 1 week after MI. Doppler echocardiogram was performed in 84 female Wistar rats 1 week after MI to determine infarction size, left chambers dimensions, fractional area change (FAC) of the left ventricle (LV), mitral inflow and tissue Doppler, myocardial performance index (MPI), and signs of pulmonary hypertension. The 365-day follow-up showed 53.6% mortality rate. Nonsurvivors showed larger (P or=0.60 (RR 3.49, 95% CI, 1.80-6.76), LV systolic area >or=0.26 cm(2) (RR 4.38, 95% CI, 1.88-10.21), E/E' ratio >or=20.3 (RR 2.12, 95% CI, 1.15-4.34), and E/A ratio associated with FAC (RR 2.99, 95% CI, 1.44-6.18). Some diastolic and systolic Doppler echocardiographic parameters in rats may be able to predict late mortality risk after MI.

Image processing of full-field strain data and its use in model updating

International Nuclear Information System (INIS)

Wang, W; Mottershead, J E; Sebastian, C M; Patterson, E A

2011-01-01

Finite element model updating is an inverse problem based on measured structural outputs, typically natural frequencies. Full-field responses such as static stress/strain patterns and vibration mode shapes contain valuable information for model updating but within large volumes of highly-redundant data. Pattern recognition and image processing provide feasible techniques to extract effective and efficient information, often known as shape features, from this data. For instance, the Zernike polynomials having the properties of orthogonality and rotational invariance are powerful decomposition kernels for a shape defined within a unit circle. In this paper, full field strain patterns for a specimen, in the form of a square plate with a circular hole, under a tensile load are considered. Effective shape features can be constructed by a set of modified Zernike polynomials. The modification includes the application of a weighting function to the Zernike polynomials so that high strain magnitudes around the hole are well represented. The Gram-Schmidt process is then used to ensure orthogonality for the obtained decomposition kernels over the domain of the specimen. The difference between full-field strain patterns measured by digital image correlation (DIC) and reconstructed using 15 shape features (Zernike moment descriptors, ZMDs) at different steps in the elasto-plastic deformation of the specimen is found to be very small. It is significant that only a very small number of shape features are necessary and sufficient to represent the full-field data. Model updating of nonlinear elasto-plastic material properties is carried out by adjusting the parameters of a FE model until the FE strain pattern converges upon the measured strains as determined using ZMDs.

A new nonlinear parameter in the developed strain-to-applied strain of the soft tissues and its application in ultrasound elasticity imaging.

Science.gov (United States)

Xu, Jingping; Tripathy, Sakya; Rubin, Jonathan M; Stidham, Ryan W; Johnson, Laura A; Higgins, Peter D R; Kim, Kang

2012-03-01

Strain developed under quasi-static deformation has been mostly used in ultrasound elasticity imaging (UEI) to determine the stiffness change of tissues. However, the strain measure in UEI is often less sensitive to a subtle change of stiffness. This is particularly true for Crohn's disease where we have applied strain imaging to the differentiation of acutely inflamed bowel from chronically fibrotic bowel. In this study, a new nonlinear elastic parameter of the soft tissues is proposed to overcome this limit. The purpose of this study is to evaluate the newly proposed method and demonstrate its feasibility in the UEI. A nonlinear characteristic of soft tissues over a relatively large dynamic range of strain was investigated. A simplified tissue model based on a finite element (FE) analysis was integrated with a laboratory developed ultrasound radio-frequency (RF) signal synthesis program. Two-dimensional speckle tracking was applied to this model to simulate the nonlinear behavior of the strain developed in a target inclusion over the applied average strain to the surrounding tissues. A nonlinear empirical equation was formulated and optimized to best match the developed strain-to-applied strain relation obtained from the FE simulation. The proposed nonlinear equation was applied to in vivo measurements and nonlinear parameters were further empirically optimized. For an animal model, acute and chronic inflammatory bowel disease was induced in Lewis rats with trinitrobenzene sulfonic acid (TNBS)-ethanol treatments. After UEI, histopathology and direct mechanical measurements were performed on the excised tissues. The extracted nonlinear parameter from the developed strain-to-applied strain relation differentiated the three different tissue types with 1.96 ± 0.12 for normal, 1.50 ± 0.09 for the acutely inflamed and 1.03 ± 0.08 for the chronically fibrotic tissue. T-tests determined that the nonlinear parameters between normal, acutely inflamed and fibrotic tissue

Magnetic resonance imaging detects significant sex differences in human myocardial strain

Directory of Open Access Journals (Sweden)

Reynolds Lina M

2011-08-01

Full Text Available Abstract Background The pathophysiology responsible for the significant outcome disparities between men and women with cardiac disease is largely unknown. Further investigation into basic cardiac physiological differences between the sexes is needed. This study utilized magnetic resonance imaging (MRI-based multiparametric strain analysis to search for sex-based differences in regional myocardial contractile function. Methods End-systolic strain (circumferential, longitudinal, and radial was interpolated from MRI-based radiofrequency tissue tagging grid point displacements in each of 60 normal adult volunteers (32 females. Results The average global left ventricular (LV strain among normal female volunteers (n = 32 was significantly larger in absolute value (functionally better than in normal male volunteers (n = 28 in both the circumferential direction (Male/Female = -0.19 ± 0.02 vs. -0.21 ± 0.02; p = 0.025 and longitudinal direction (Male/Female = -0.14 ± 0.03 vs. -0.16 ± 0.02; p = 0.007. Conclusions The finding of significantly larger circumferential and longitudinal LV strain among normal female volunteers suggests that baseline contractile differences between the sexes may contribute to the well-recognized divergence in cardiovascular disease outcomes. Further work is needed in order to determine the pathologic changes that occur in LV strain between women and men with the onset of cardiovascular disease.

Echocardiographic predictors of exercise capacity and mortality in chronic obstructive pulmonary disease

DEFF Research Database (Denmark)

Schoos, Mikkel Malby; Dalsgaard, Morten; Kjærgaard, Jesper

2013-01-01

Chronic obstructive pulmonary disease (COPD) reduces exercise capacity, but lung function parameters do not fully explain functional class and lung-heart interaction could be the explanation. We evaluated echocardiographic predictors of mortality and six minutes walking distance (6MWD), a marker...... for quality of life and mortality in COPD....

Echocardiographic Parameters and Survival in Chagas Heart Disease with Severe Systolic Dysfunction

International Nuclear Information System (INIS)

Rassi, Daniela do Carmo; Vieira, Marcelo Luiz Campos; Arruda, Ana Lúcia Martins; Hotta, Viviane Tiemi; Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador

2014-01-01

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction < 35%. Study with retrospective analysis of pre-specified echocardiographic parameters prospectively collected from 60 patients included in the Multicenter Randomized Trial of Cell Therapy in Patients with Heart Diseases (Estudo Multicêntrico Randomizado de Terapia Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p < 0.0001) and E/Em ratio (HR = 0.95; p = 0.1261) were excluded. The indexed left atrial volume was an independent predictor in relation to the endpoint, and values > 70.71 mL/m 2 were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction

Echocardiographic reference ranges in older children and adolescents in sub-Saharan Africa.

Science.gov (United States)

Majonga, Edith D; Rehman, Andrea M; McHugh, Grace; Mujuru, Hilda A; Nathoo, Kusum; Patel, Mohammad S; Munyati, Shungu; Odland, Jon O; Kranzer, Katharina; Kaski, Juan P; Ferrand, Rashida A

2017-12-01

Echocardiographic reference ranges are important to identify abnormalities of cardiac dimensions. Reference ranges for children in sub-Saharan Africa have not been established. The aim of this study was to establish echocardiographic z-score references for Black children in sub-Saharan Africa. 282 healthy subjects aged 6-16years (143 [51%] males) with no known history of cardiac disease were enrolled in the study in Harare, Zimbabwe between 2014 and 2016. Standard M-mode echocardiography was performed and nine cardiac chamber dimensions were obtained. Two non-linear statistical models (gamma weighted model and cubic polynomial model) were tested on the data and the best fitting model was used to calculate z-scores of these cardiac chamber measures. The reference ranges are presented on scatter plots against BSA. Normative data for the following cardiac measures were obtained and z-scores calculated: right ventricular diameter at end diastole (RVEDD); left ventricular diameter at end diastole (LVEDD) and systole (LVESD); interventricular septal wall thickness at end diastole (IVSd) and systole (IVSs); left ventricular posterior wall thickness at end diastole (LVPWd) and systole (LVPWs); left atrium diameter at end systole (LA) and tricuspid annular plane systolic excursion (TAPSE). Girls had higher values for BMI and heart rate than boys (p=0.048 and p=0.001, respectively). Mean interventricular septal and left ventricular posterior walls thickness was higher than published normal values in predominantly Caucasian populations. These are the first echocardiographic reference ranges for children from sub Saharan Africa and will allow accurate assessment of cardiac dimensions in clinical practice. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Echocardiographic Parameters and Survival in Chagas Heart Disease with Severe Systolic Dysfunction

Energy Technology Data Exchange (ETDEWEB)

Rassi, Daniela do Carmo, E-mail: dani.rassi@hotmail.com [Faculdade de Medicina e Hospital das Clínicas da Universidade Federal de Goiás (UFG), Goiânia, GO (Brazil); Vieira, Marcelo Luiz Campos [Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Arruda, Ana Lúcia Martins [Instituto de Radiologia da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Hotta, Viviane Tiemi [Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil); Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador [Faculdade de Medicina e Hospital das Clínicas da Universidade Federal de Goiás (UFG), Goiânia, GO (Brazil)

2014-03-15

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction < 35%. Study with retrospective analysis of pre-specified echocardiographic parameters prospectively collected from 60 patients included in the Multicenter Randomized Trial of Cell Therapy in Patients with Heart Diseases (Estudo Multicêntrico Randomizado de Terapia Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p < 0.0001) and E/Em ratio (HR = 0.95; p = 0.1261) were excluded. The indexed left atrial volume was an independent predictor in relation to the endpoint, and values > 70.71 mL/m{sup 2} were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction.

Cognitive Machine-Learning Algorithm for Cardiac Imaging: A Pilot Study for Differentiating Constrictive Pericarditis From Restrictive Cardiomyopathy.

Science.gov (United States)

Sengupta, Partho P; Huang, Yen-Min; Bansal, Manish; Ashrafi, Ali; Fisher, Matt; Shameer, Khader; Gall, Walt; Dudley, Joel T

2016-06-01

Associating a patient's profile with the memories of prototypical patients built through previous repeat clinical experience is a key process in clinical judgment. We hypothesized that a similar process using a cognitive computing tool would be well suited for learning and recalling multidimensional attributes of speckle tracking echocardiography data sets derived from patients with known constrictive pericarditis and restrictive cardiomyopathy. Clinical and echocardiographic data of 50 patients with constrictive pericarditis and 44 with restrictive cardiomyopathy were used for developing an associative memory classifier-based machine-learning algorithm. The speckle tracking echocardiography data were normalized in reference to 47 controls with no structural heart disease, and the diagnostic area under the receiver operating characteristic curve of the associative memory classifier was evaluated for differentiating constrictive pericarditis from restrictive cardiomyopathy. Using only speckle tracking echocardiography variables, associative memory classifier achieved a diagnostic area under the curve of 89.2%, which improved to 96.2% with addition of 4 echocardiographic variables. In comparison, the area under the curve of early diastolic mitral annular velocity and left ventricular longitudinal strain were 82.1% and 63.7%, respectively. Furthermore, the associative memory classifier demonstrated greater accuracy and shorter learning curves than other machine-learning approaches, with accuracy asymptotically approaching 90% after a training fraction of 0.3 and remaining flat at higher training fractions. This study demonstrates feasibility of a cognitive machine-learning approach for learning and recalling patterns observed during echocardiographic evaluations. Incorporation of machine-learning algorithms in cardiac imaging may aid standardized assessments and support the quality of interpretations, particularly for novice readers with limited experience. © 2016

A rapid echocardiographic screening protocol for rheumatic heart disease in Samoa: a high prevalence of advanced disease.

Science.gov (United States)

Allen, Marvin; Allen, John; Naseri, Take; Gardner, Rebecca; Tolley, Dennis; Allen, Lori

2017-10-01

Echocardiography has been proposed as a method to screen children for rheumatic heart disease. The World Heart Federation has established guidelines for echocardiographic screening. In this study, we describe a rapid echocardiogram screening protocol according to the World Heart Federation guidelines in Samoa, endemic for rheumatic heart disease. We performed echocardiogram screening in schoolchildren in Samoa between 2013 and 2015. A brief screening echocardiogram was performed on all students. Children with predefined criteria suspicious for rheumatic hear diseases were referred for a more comprehensive echocardiogram. Complete echocardiograms were classified according to the World Heart Federation guidelines and severity of valve disease. Echocardiographic screening was performed on 11,434 children, with a mean age of 10.2 years; 51% of them were females. A total of 558 (4.8%) children underwent comprehensive echocardiography, including 49 students who were randomly selected as controls. Definite rheumatic heart disease was observed in 115 students (10.0 per 1000): 92 students were classified as borderline (8.0 per 1000) and 23 with CHD. Advanced disease was identified in 50 students (4.4 per 1000): 15 with severe mitral regurgitation, five with severe aortic regurgitation, 11 with mitral stenoses, and 19 with mitral and aortic valve disease. We successfully applied a rapid echocardiographic screening protocol to a large number of students over a short time period - 28 days of screening over a 3-year time period - to identify a high prevalence of rheumatic heart disease. We also reported a significantly higher rate of advanced disease compared with previously published echocardiographic screening programmes.

Which echocardiographic parameter is a better marker of volume status in hemodialysis patients?

Science.gov (United States)

Sabaghian, Tahereh; Hajibaratali, Bahareh; Samavat, Shiva

2016-11-01

Bio-impedance analysis (BIA) is a preferred method for estimating the volume status. However, it cannot be utilized in daily practice. Since the assessment of the volume status is important and challenging for hemodialysis (HD) patients, the aim of study was to determine the volume status in chronic HD patients using echocardiographic parameters and assess its correlation with BIA. In this cross-sectional analysis, echocardiography and BIA were performed on 30 chronic HD patients 30 min before and 30 min after dialysis. All the cases of dialysis were performed in the middle of the week. This study also assessed the correlation between echocardiographic parameters and BIA parameters. There were significant differences between ECW, TBW, and TBW% (TBW/W) before and after HD. Significant differences were observed between echocardiographic parameters of IVCD, IVCDi min , IVCDi max before and after the HD. LVEDD, LVESD, LA area, mitral valve inflow, E/E', and IVRT, were improved after dialysis, too. There was a significant correlation between IVCDi min as an index of volume status, ECW% and TBW% before HD and IVCDi min change after dialysis had a significant correlation with %ECW change after dialysis. Comparison between hypertensive and non-hypertensive groups indicated IVCDi min was significantly lower in non-hypertensive group after dialysis. Our results showed a correlation between IVCDi min and BIA parameters before HD. So, it seems that IVCDi min can be a good parameter for determining the volume status of HD patients. However, further studies, with larger sample size and with a prospective study design, are required to confirm these results.

Strain Imaging of Nanoscale Semiconductor Heterostructures with X-Ray Bragg Projection Ptychography

Science.gov (United States)

Holt, Martin V.; Hruszkewycz, Stephan O.; Murray, Conal E.; Holt, Judson R.; Paskiewicz, Deborah M.; Fuoss, Paul H.

2014-04-01

We report the imaging of nanoscale distributions of lattice strain and rotation in complementary components of lithographically engineered epitaxial thin film semiconductor heterostructures using synchrotron x-ray Bragg projection ptychography (BPP). We introduce a new analysis method that enables lattice rotation and out-of-plane strain to be determined independently from a single BPP phase reconstruction, and we apply it to two laterally adjacent, multiaxially stressed materials in a prototype channel device. These results quantitatively agree with mechanical modeling and demonstrate the ability of BPP to map out-of-plane lattice dilatation, a parameter critical to the performance of electronic materials.

Strain analysis in CRT candidates using the novel segment length in cine (SLICE) post-processing technique on standard CMR cine images.

Science.gov (United States)

Zweerink, Alwin; Allaart, Cornelis P; Kuijer, Joost P A; Wu, LiNa; Beek, Aernout M; van de Ven, Peter M; Meine, Mathias; Croisille, Pierre; Clarysse, Patrick; van Rossum, Albert C; Nijveldt, Robin

2017-12-01

Although myocardial strain analysis is a potential tool to improve patient selection for cardiac resynchronization therapy (CRT), there is currently no validated clinical approach to derive segmental strains. We evaluated the novel segment length in cine (SLICE) technique to derive segmental strains from standard cardiovascular MR (CMR) cine images in CRT candidates. Twenty-seven patients with left bundle branch block underwent CMR examination including cine imaging and myocardial tagging (CMR-TAG). SLICE was performed by measuring segment length between anatomical landmarks throughout all phases on short-axis cines. This measure of frame-to-frame segment length change was compared to CMR-TAG circumferential strain measurements. Subsequently, conventional markers of CRT response were calculated. Segmental strains showed good to excellent agreement between SLICE and CMR-TAG (septum strain, intraclass correlation coefficient (ICC) 0.76; lateral wall strain, ICC 0.66). Conventional markers of CRT response also showed close agreement between both methods (ICC 0.61-0.78). Reproducibility of SLICE was excellent for intra-observer testing (all ICC ≥0.76) and good for interobserver testing (all ICC ≥0.61). The novel SLICE post-processing technique on standard CMR cine images offers both accurate and robust segmental strain measures compared to the 'gold standard' CMR-TAG technique, and has the advantage of being widely available. • Myocardial strain analysis could potentially improve patient selection for CRT. • Currently a well validated clinical approach to derive segmental strains is lacking. • The novel SLICE technique derives segmental strains from standard CMR cine images. • SLICE-derived strain markers of CRT response showed close agreement with CMR-TAG. • Future studies will focus on the prognostic value of SLICE in CRT candidates.

Influence of Angiotensin-Converting-Enzyme Gene Polymorphism on Echocardiographic Data of Patients with Ischemic Heart Failure

Science.gov (United States)

Duque, Gustavo Salgado; da Silva, Dayse Aparecida; de Albuquerque, Felipe Neves; Schneider, Roberta Siuffo; Gimenez, Alinne; Pozzan, Roberto; Rocha, Ricardo Mourilhe; de Albuquerque, Denilson Campos

2016-01-01

Background Association between angiotensin-converting-enzyme (ACE) gene polymorphisms and different clinical and echocardiographic outcomes has been described in patients with heart failure (HF) and coronary artery disease. Studying the genetic profile of the local population with both diseases is necessary to assess the occurrence of that association. Objectives To assess the frequency of ACE gene polymorphisms in patients with ischemic HF in a Rio de Janeiro population, as well as its association with echocardiographic findings. Methods Genetic assessment of I/D ACE polymorphism in association with clinical, laboratory and echocardiographic analysis of 99 patients. Results The allele frequency was: 53 I alleles, and 145 D alleles. Genotype frequencies were: 49.5% DD; 47.48% DI; 3.02% II. Drug treatment was optimized: 98% on beta-blockers, and 84.8% on ACE inhibitors or angiotensin-receptor blocker. Echocardiographic findings: difference between left ventricular diastolic diameters (ΔLVDD) during follow-up: 2.98±8.94 (DD) vs. 0.68±8.12 (DI) vs. -11.0±7.00 (II), p=0.018; worsening during follow-up of the LV systolic diameter (LVSD): 65.3% DD vs. 19.0% DI vs. 0.0% II, p=0.01; of the LV diastolic diameter (LVDD): 65.3% DD vs. 46.8% DI vs. 0.0% II, p=0.03; and of the LV ejection fraction (LVEF): 67.3% DD vs. 40.4% DI vs. 33.3% II, p=0.024. Correlated with D allele: ΔLVEF, ΔLVSD, ΔLVDD. Conclusions More DD genotype patients had worsening of the LVEF, LVSD and LVDD, followed by DI genotype patients, while II genotype patients had the best outcome. The same pattern was observed for ΔLVDD. PMID:27812677

The Acoustic Lens Design and in Vivo Use of a Multifunctional Catheter Combining Intracardiac Ultrasound Imaging and Electrophysiology Sensing

Science.gov (United States)

Stephens, Douglas N.; Cannata, Jonathan; Liu, Ruibin; Zhao, Jian Zhong; Shung, K. Kirk; Nguyen, Hien; Chia, Raymond; Dentinger, Aaron; Wildes, Douglas; Thomenius, Kai E.; Mahajan, Aman; Shivkumar, Kalyanam; Kim, Kang; O’Donnell, Matthew; Sahn, David

2009-01-01

A multifunctional 9F intracardiac imaging and electrophysiology mapping catheter was developed and tested to help guide diagnostic and therapeutic intracardiac electrophysiology (EP) procedures. The catheter tip includes a 7.25-MHz, 64-element, side-looking phased array for high resolution sector scanning. Multiple electrophysiology mapping sensors were mounted as ring electrodes near the array for electrocardiographic synchronization of ultrasound images. The catheter array elevation beam performance in particular was investigated. An acoustic lens for the distal tip array designed with a round cross section can produce an acceptable elevation beam shape; however, the velocity of sound in the lens material should be approximately 155 m/s slower than in tissue for the best beam shape and wide bandwidth performance. To help establish the catheter’s unique ability for integration with electrophysiology interventional procedures, it was used in vivo in a porcine animal model, and demonstrated both useful intracardiac echocardiographic visualization and simultaneous 3-D positional information using integrated electroanatomical mapping techniques. The catheter also performed well in high frame rate imaging, color flow imaging, and strain rate imaging of atrial and ventricular structures. PMID:18407850

A stepwise composite echocardiographic score predicts severe pulmonary hypertension in patients with interstitial lung disease.

Science.gov (United States)

Bax, Simon; Bredy, Charlene; Kempny, Aleksander; Dimopoulos, Konstantinos; Devaraj, Anand; Walsh, Simon; Jacob, Joseph; Nair, Arjun; Kokosi, Maria; Keir, Gregory; Kouranos, Vasileios; George, Peter M; McCabe, Colm; Wilde, Michael; Wells, Athol; Li, Wei; Wort, Stephen John; Price, Laura C

2018-04-01

European Respiratory Society (ERS) guidelines recommend the assessment of patients with interstitial lung disease (ILD) and severe pulmonary hypertension (PH), as defined by a mean pulmonary artery pressure (mPAP) ≥35 mmHg at right heart catheterisation (RHC). We developed and validated a stepwise echocardiographic score to detect severe PH using the tricuspid regurgitant velocity and right atrial pressure (right ventricular systolic pressure (RVSP)) and additional echocardiographic signs. Consecutive ILD patients with suspected PH underwent RHC between 2005 and 2015. Receiver operating curve analysis tested the ability of components of the score to predict mPAP ≥35 mmHg, and a score devised using a stepwise approach. The score was tested in a contemporaneous validation cohort. The score used "additional PH signs" where RVSP was unavailable, using a bootstrapping technique. Within the derivation cohort (n=210), a score ≥7 predicted severe PH with 89% sensitivity, 71% specificity, positive predictive value 68% and negative predictive value 90%, with similar performance in the validation cohort (n=61) (area under the curve (AUC) 84.8% versus 83.1%, p=0.8). Although RVSP could be estimated in 92% of studies, reducing this to 60% maintained a fair accuracy (AUC 74.4%). This simple stepwise echocardiographic PH score can predict severe PH in patients with ILD.

Implementation of the stress echocardiography in an echocardiographic laboratory

International Nuclear Information System (INIS)

Solis Brizuela, Felix

2013-01-01

The logistics for the implementation of the stress echocardiography is defined with based on current recommendations, for an echocardiography laboratory. The protocols established to perform the studies and procedures of this diagnostic method are exposed. The elementary conditions to realize with safety the stress echocardiography are established. Recent literature on the evaluation of new echocardiographic techniques is reviewed to determine their usefulness in stress testing. The assessment of stress echocardiography is developed. The stress echocardiography has been the procedure with high sensitivity and specificity for the diagnosis of coronary artery disease [es

Echocardiographic Assessment of Pulmonary Arterial Hypertension for Pediatricians and Neonatologists

Directory of Open Access Journals (Sweden)

Gregory James Skinner

2017-09-01

Full Text Available There is a growing awareness of the role that increased pulmonary vascular resistance (PVR plays in many pathologies; therefore, assessment of pulmonary artery pressure (PAP is an increasingly requested investigation in the critical care environment. This article will go through the basic concepts regarding PAP and PVR, then will go on to outline the various echocardiographic parameters which are used to assess them. Finally, an outline of how to undertake this assessment will be presented.

The effects of detomidine, romifidine or acepromazine on echocardiographic measurements and cardiac function in normal horses.

Science.gov (United States)

Buhl, Rikke; Ersbøll, Annette K; Larsen, Nanna H; Eriksen, Lis; Koch, Jørgen

2007-01-01

To evaluate by echo- and electrocardiography the cardiac effects of sedation with detomidine hydrochloride, romifidine hydrochloride or acepromazine maleate in horses. An experimental study using a cross-over design without randomization. Eight clinically normal Standardbred trotters. Echocardiographic examinations (two-dimensional, guided M-mode and colour Doppler) were recorded on five different days. Heart rate (HR) and standard limb lead electrocardiograms were also obtained. Subsequently, horses were sedated with detomidine (0.01 mg kg(-1)), romifidine (0.04 mg kg(-1)) or acepromazine (0.1 mg kg(-1)) administered intravenously and all examinations repeated. Heart rate before treatment with the three drugs did not differ significantly (p = 0.98). Both detomidine and romifidine induced a significant decrease (p detomidine, there was a significant increase in LVIDd (left ventricular internal diameter in diastole; p = 0.034) and LVIDs (left ventricular internal diameter in systole; p detomidine and to a lesser extent romifidine at the doses given in this study has a significant effect on heart function, echocardiographic measurements of heart dimensions and the occurrence of valvular regurgitation. Although the clinical significance of these results may be minimal, the potential effects of sedative drugs should be taken into account when echocardiographic variables are interpreted in clinical cases.

Echocardiographic findings and joint hypermobility: patients with mitral valve prolapse vs. healthy controls

Directory of Open Access Journals (Sweden)

Moradmand S

2008-11-01

Full Text Available "nBackground: Mitral valve prolapse is a relatively common valvular abnormality in most communities and joint hypermobility (JHM is also seen in many healthy people as well as in certain clinical disorders, such as Marfan syndrome. The present study was designed to investigate the association between joint hypermobility and mitral valve prolapse (MVP in an Iranian population sample. "nMethods: Fifty-seven patients with nonrheumatic and isolated mitral anterior leaflet prolapse (24 men and 33 women, mean age 23.5 +/-2.3 and 51 healthy subjects (20 men and 31 women, mean age 22.9+/-2.3 were studied. The presence of JHM was evaluated according to the Carter-Wilkinson & Beighton criteria. Echocardiographic examination was performed in all subjects and the correlation between the echocardiographic features of the mitral valve and the hypermobility score were investigated. "nResults: The frequency of JHM in patients with MVP was found to be significantly higher than that of controls (26.3% vs. 7.8%, with mean JHM scores of 3.1+/-2.2 and 1.9+/-1.7, respectively. The patients in the MVP group had significantly increased the anterior mitral leaflet thickness (AMLT, 3.4+/-0.4 mm vs. 3.0+/-0.3 mm; p<0.0005 and maximal leaflet displacement (MLD, 2.4+/-0.3 mm vs. 1.5+/-0.2 mm; p<0.0005 compared to the controls. "nConclusions: We detect a statistically significant relationship between isolated MVP and joint hypermobility as well as between the severity of JHM and echocardiographic features of the mitral leaflets. These results suggest a common etiology for MVP and JHM, which should be investigated in future well-conducted studies.

Incidence of mitral valve prolapse in one hundred clinically stable newborn baby girls: an echocardiographic study.

Science.gov (United States)

Chandraratna, P A; Vlahovich, G; Kong, Y; Wilson, D

1979-09-01

Clinical and echocardiographic examinations were performed on 100 clinically stable, newborn baby girls. Mitral valve prolapse was noted on the echocardiograms of seven babies. Three subjects had systolic clicks, two of whom had systolic murmurs following the click. The four other babies who had echocardiographic evidence of mitral valve prolapse had no abnormal auscultatory signs. Of the 93 babies without evidence of mitral prolapse, 91 had normal echocardiograms and auscultatory features; one was noted to have a murmur consistent with a ventricular septal defect, and another had an eccentric aortic valve on the echocardiogram which was suggestive of a bicuspid aortic valve. Serial studies on our group of subjects will yield useful information regarding the natural history of mitral valve prolapse.

THE USE OF DIGITAL IMAGE CORRELATION IN THE STUDY OF ACHILLES TENDON STRAIN FIELD

Directory of Open Access Journals (Sweden)

Krzysztof Holak

2017-06-01

Full Text Available The paper presents an application of vision-based measurement method in experimental mechanics of biological materials.  The displacement and strain fields of human Achilles tendon specimen under tensile test were computed using digital image correlation method. Different software applications, both commercial as well as open source ones, were compared. The performance of algorithms was tested based on a referential measurement, carried out by a commercial software with affine model of deformation implemented. The root mean square error of a difference between strain obtained using reference measurement and each of the analyzed programs was computed. Additionally,  an example of full field computation of displacement and strain field was presented.

Novel image analysis methods for quantification of in situ 3-D tendon cell and matrix strain.

Science.gov (United States)

Fung, Ashley K; Paredes, J J; Andarawis-Puri, Nelly

2018-01-23

Macroscopic tendon loads modulate the cellular microenvironment leading to biological outcomes such as degeneration or repair. Previous studies have shown that damage accumulation and the phases of tendon healing are marked by significant changes in the extracellular matrix, but it remains unknown how mechanical forces of the extracellular matrix are translated to mechanotransduction pathways that ultimately drive the biological response. Our overarching hypothesis is that the unique relationship between extracellular matrix strain and cell deformation will dictate biological outcomes, prompting the need for quantitative methods to characterize the local strain environment. While 2-D methods have successfully calculated matrix strain and cell deformation, 3-D methods are necessary to capture the increased complexity that can arise due to high levels of anisotropy and out-of-plane motion, particularly in the disorganized, highly cellular, injured state. In this study, we validated the use of digital volume correlation methods to quantify 3-D matrix strain using images of naïve tendon cells, the collagen fiber matrix, and injured tendon cells. Additionally, naïve tendon cell images were used to develop novel methods for 3-D cell deformation and 3-D cell-matrix strain, which is defined as a quantitative measure of the relationship between matrix strain and cell deformation. The results support that these methods can be used to detect strains with high accuracy and can be further extended to an in vivo setting for observing temporal changes in cell and matrix mechanics during degeneration and healing. Copyright © 2017. Published by Elsevier Ltd.

Second Harmonic Imaging improves Echocardiograph Quality on board the International Space Station

Science.gov (United States)

Garcia, Kathleen; Sargsyan, Ashot; Hamilton, Douglas; Martin, David; Ebert, Douglas; Melton, Shannon; Dulchavsky, Scott

2008-01-01

Ultrasound (US) capabilities have been part of the Human Research Facility (HRF) on board the International Space Station (ISS) since 2001. The US equipment on board the ISS includes a first-generation Tissue Harmonic Imaging (THI) option. Harmonic imaging (HI) is the second harmonic response of the tissue to the ultrasound beam and produces robust tissue detail and signal. Since this is a first-generation THI, there are inherent limitations in tissue penetration. As a breakthrough technology, HI extensively advanced the field of ultrasound. In cardiac applications, it drastically improves endocardial border detection and has become a common imaging modality. U.S. images were captured and stored as JPEG stills from the ISS video downlink. US images with and without harmonic imaging option were randomized and provided to volunteers without medical education or US skills for identification of endocardial border. The results were processed and analyzed using applicable statistical calculations. The measurements in US images using HI improved measurement consistency and reproducibility among observers when compared to fundamental imaging. HI has been embraced by the imaging community at large as it improves the quality and data validity of US studies, especially in difficult-to-image cases. Even with the limitations of the first generation THI, HI improved the quality and measurability of many of the downlinked images from the ISS and should be an option utilized with cardiac imaging on board the ISS in all future space missions.

Echocardiographic Screening of Rheumatic Heart Disease in American Samoa.

Science.gov (United States)

Huang, Jennifer H; Favazza, Michael; Legg, Arthur; Holmes, Kathryn W; Armsby, Laurie; Eliapo-Unutoa, Ipuniuesea; Pilgrim, Thomas; Madriago, Erin J

2018-01-01

While rheumatic heart disease (RHD) is a treatable disease nearly eradicated in the United States, it remains the most common form of acquired heart disease in the developing world. This study used echocardiographic screening to determine the prevalence of RHD in children in American Samoa. Screening took place at a subset of local schools. Private schools were recruited and public schools underwent cluster randomization based on population density. We collected survey information and performed a limited physical examination and echocardiogram using the World Heart Federation protocol for consented school children aged 5-18 years old. Of 2200 students from two private high schools and two public primary schools, 1058 subjects consented and were screened. Overall, 133 (12.9%) children were identified as having either definite (3.5%) or borderline (9.4%) RHD. Of the patients with definitive RHD, 28 subjects had abnormal mitral valves with pathologic regurgitation, three mitral stenosis, three abnormal aortic valves with pathologic regurgitation, and seven borderline mitral and aortic valve disease. Of the subjects with borderline disease, 77 had pathologic mitral regurgitation, 12 pathologic aortic regurgitation, and 7 at least two features of mitral valve disease without pathologic regurgitation or stenosis. Rheumatic heart disease remains a major cause of morbidity and mortality worldwide. The prevalence of RHD in American Samoa (12.9%) is to date the highest reported in the world literature. Echocardiographic screening of school children is feasible, while reliance on murmur and Jones criteria is not helpful in identifying children with RHD.

Can echocardiographic findings predict falls in older persons?

Directory of Open Access Journals (Sweden)

Nathalie van der Velde

Full Text Available BACKGROUND: The European and American guidelines state the need for echocardiography in patients with syncope. 50% of older adults with syncope present with a fall. Nonetheless, up to now no data have been published addressing echocardiographic abnormalities in older fallers. METHOD AND FINDINGS: In order to determine the association between echocardiographic abnormalities and falls in older adults, we performed a prospective cohort study, in which 215 new consecutive referrals (age 77.4, SD 6.0 of a geriatric outpatient clinic of a Dutch university hospital were included. During the previous year, 139 had experienced a fall. At baseline, all patients underwent routine two-dimensional and Doppler echocardiography. Falls were recorded during a three-month follow-up. Multivariate adjustment for confounders was performed with a Cox proportional hazards model. 55 patients (26% fell at least once during follow-up. The adjusted hazard ratio of a fall during follow-up was 1.35 (95% CI, 1.08-1.71 for pulmonary hypertension, 1.66 (95% CI, 1.01 to 2.89 for mitral regurgitation, 2.41 (95% CI, 1.32 to 4.37 for tricuspid regurgitation and 1.76 (95% CI, 1.03 to 3.01 for pulmonary regurgitation. For aortic regurgitation the risk of a fall was also increased, but non-significantly (hazard ratio, 1.57 [95% CI, 0.85 to 2.92]. Trend analysis of the severity of the different regurgitations showed a significant relationship for mitral, tricuspid and pulmonary valve regurgitation and pulmonary hypertension. CONCLUSIONS: Echo (Doppler cardiography can be useful in order to identify risk indicators for falling. Presence of pulmonary hypertension or regurgitation of mitral, tricuspid or pulmonary valves was associated with a higher fall risk. Our study indicates that the diagnostic work-up for falls in older adults might be improved by adding an echo (Doppler cardiogram in selected groups.

Strain analysis in CRT candidates using the novel segment length in cine (SLICE) post-processing technique on standard CMR cine images

Energy Technology Data Exchange (ETDEWEB)

Zweerink, Alwin; Allaart, Cornelis P.; Wu, LiNa; Beek, Aernout M.; Rossum, Albert C. van; Nijveldt, Robin [VU University Medical Center, Department of Cardiology, and Institute for Cardiovascular Research (ICaR-VU), Amsterdam (Netherlands); Kuijer, Joost P.A. [VU University Medical Center, Department of Physics and Medical Technology, Amsterdam (Netherlands); Ven, Peter M. van de [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands); Meine, Mathias [University Medical Center, Department of Cardiology, Utrecht (Netherlands); Croisille, Pierre; Clarysse, Patrick [Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, Saint-Etienne (France)

2017-12-15

Although myocardial strain analysis is a potential tool to improve patient selection for cardiac resynchronization therapy (CRT), there is currently no validated clinical approach to derive segmental strains. We evaluated the novel segment length in cine (SLICE) technique to derive segmental strains from standard cardiovascular MR (CMR) cine images in CRT candidates. Twenty-seven patients with left bundle branch block underwent CMR examination including cine imaging and myocardial tagging (CMR-TAG). SLICE was performed by measuring segment length between anatomical landmarks throughout all phases on short-axis cines. This measure of frame-to-frame segment length change was compared to CMR-TAG circumferential strain measurements. Subsequently, conventional markers of CRT response were calculated. Segmental strains showed good to excellent agreement between SLICE and CMR-TAG (septum strain, intraclass correlation coefficient (ICC) 0.76; lateral wall strain, ICC 0.66). Conventional markers of CRT response also showed close agreement between both methods (ICC 0.61-0.78). Reproducibility of SLICE was excellent for intra-observer testing (all ICC ≥0.76) and good for interobserver testing (all ICC ≥0.61). The novel SLICE post-processing technique on standard CMR cine images offers both accurate and robust segmental strain measures compared to the 'gold standard' CMR-TAG technique, and has the advantage of being widely available. (orig.)

Strain analysis in CRT candidates using the novel segment length in cine (SLICE) post-processing technique on standard CMR cine images

International Nuclear Information System (INIS)

Zweerink, Alwin; Allaart, Cornelis P.; Wu, LiNa; Beek, Aernout M.; Rossum, Albert C. van; Nijveldt, Robin; Kuijer, Joost P.A.; Ven, Peter M. van de; Meine, Mathias; Croisille, Pierre; Clarysse, Patrick

2017-01-01

Although myocardial strain analysis is a potential tool to improve patient selection for cardiac resynchronization therapy (CRT), there is currently no validated clinical approach to derive segmental strains. We evaluated the novel segment length in cine (SLICE) technique to derive segmental strains from standard cardiovascular MR (CMR) cine images in CRT candidates. Twenty-seven patients with left bundle branch block underwent CMR examination including cine imaging and myocardial tagging (CMR-TAG). SLICE was performed by measuring segment length between anatomical landmarks throughout all phases on short-axis cines. This measure of frame-to-frame segment length change was compared to CMR-TAG circumferential strain measurements. Subsequently, conventional markers of CRT response were calculated. Segmental strains showed good to excellent agreement between SLICE and CMR-TAG (septum strain, intraclass correlation coefficient (ICC) 0.76; lateral wall strain, ICC 0.66). Conventional markers of CRT response also showed close agreement between both methods (ICC 0.61-0.78). Reproducibility of SLICE was excellent for intra-observer testing (all ICC ≥0.76) and good for interobserver testing (all ICC ≥0.61). The novel SLICE post-processing technique on standard CMR cine images offers both accurate and robust segmental strain measures compared to the 'gold standard' CMR-TAG technique, and has the advantage of being widely available. (orig.)

Diagnostic Value of Selected Echocardiographic Variables to Identify Pulmonary Hypertension in Dogs with Myxomatous Mitral Valve Disease.

Science.gov (United States)

Tidholm, A; Höglund, K; Häggström, J; Ljungvall, I

2015-01-01

Pulmonary hypertension (PH) is commonly associated with myxomatous mitral valve disease (MMVD). Because dogs with PH present without measureable tricuspid regurgitation (TR), it would be useful to investigate echocardiographic variables that can identify PH. To investigate associations between estimated systolic TR pressure gradient (TRPG) and dog characteristics and selected echocardiographic variables. 156 privately owned dogs. Prospective observational study comparing the estimations of TRPG with dog characteristics and selected echocardiographic variables in dogs with MMVD and measureable TR. Tricuspid regurgitation pressure gradient was significantly (P modeled as linear variables LA/Ao (P modeled as second order polynomial variables: AT/DT (P = .0039) and LVIDDn (P value for the final model was 0.45 and receiver operating characteristic curve analysis suggested the model's performance to predict PH, defined as 36, 45, and 55 mmHg as fair (area under the curve [AUC] = 0.80), good (AUC = 0.86), and excellent (AUC = 0.92), respectively. In dogs with MMVD, the presence of PH might be suspected with the combination of decreased PA AT/DT, increased RVIDDn and LA/Ao, and a small or great LVIDDn. Copyright © 2015 The Authors Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Allometric scaling of echocardiographic measurements in healthy Spanish foals with different body weight.

Science.gov (United States)

Rovira, S; Muñoz, A; Rodilla, V

2009-04-01

Scaling in biology is usually allometric, and therefore, the size of the heart may be expressed as a power function of body weight (BW). The present research analyses the echocardiographic measurements in 68 healthy Spanish foals weighed between 70 and 347kg in order to determine the correct scaling exponent for the allometric equation. The echocardiographic parameters measured were: left ventricular internal dimensions (LVID), free wall thickness (LVFWT), interventricular septum thickness (IVST) at systole (s) and diastole (d), EPSS (distance between the point E of the mitral valve and the interventricular septum), and aorta diameters at the level of the aortic valve (AOD), base of valve leaflets (ABS), sinus of Valsalva (ASV) and sino-tubular junction (AJT). Indices of left ventricular performance were calculated. It was found that LVIDd, IVSTs, AOD, and ASV have a relationship to BW raised to 0.300-0.368 power, whereas left ventricular end-diastolic volume and stroke volume scaled to BW raised to 0.731-0.712 power. With these data, appropriate values can be calculated for normal Spanish foals.

Diagnosis of Fibrosis and Activity by a Combined Use of Strain and Shear Wave Imaging in Patients with Liver Disease.

Science.gov (United States)

Yada, Norihisa; Tamaki, Nobuhura; Koizumi, Yohei; Hirooka, Masashi; Nakashima, Osamu; Hiasa, Yoichi; Izumi, Namiki; Kudo, Masatoshi

2017-01-01

Performing shear wave imaging is simple, but can be difficult when inflammation, jaundice, and congestion are present. Therefore, the correct diagnosis of liver fibrosis using shear wave imaging alone might be difficult in mild-to-moderate fibrosis cases. Strain imaging can diagnose liver fibrosis without the influence of inflammation. Therefore, the combined use of strain and shear wave imaging (combinational elastography) for cases without jaundice and congestion might be useful for evaluating fibrosis and inflammation. We enrolled consecutive patients with liver disease, without jaundice or liver congestion. Strain and shear wave imaging, blood tests, and liver biopsy were performed on the same day. The liver fibrosis index (LF index) was calculated by strain imaging; real-time tissue elastography, and the shear wave velocity (Vs) was calculated by shear wave imaging. Fibrosis index (F index) and activity index (A index) were calculated as a multiple regression equation for determining hepatic fibrosis and inflammation using histopathological diagnosis as the gold standard. The diagnostic ability of F index for fibrosis and A index for inflammation were compared using LF index and Vs. The total number of enrolled cases was 388. The area under the receiver operating characteristic (AUROC) was 0.87, 0.80, 0.83, and 0.80, at diagnosis of fibrosis stage with an F index of F1 or higher, F2 or higher, F3 or higher, and F4, respectively. The AUROC was 0.94, 0.74, and 0.76 at diagnosis of activity grade with an A index of A1 or higher, A2 or higher, and A3, respectively. The diagnostic ability of F index for liver fibrosis and A index for inflammation was higher than for other conventional diagnostic values. The combined use of strain and shear wave imaging (combinational elastography) might increase the positive diagnosis of liver fibrosis and inflammation. © 2017 S. Karger AG, Basel.

Correlation analysis of the relationship between B-type natriuretic peptide and selected echocardiographic parameters in patients with permanent pacemakers

Directory of Open Access Journals (Sweden)

Janusz Sielski

2016-01-01

Full Text Available Introduction: The present study was undertaken to evaluate the practical value of BNP measurements and echocardiographic left ventricular volume index in patients with permanent pacemakers because there are no such reports in the literature. Aim of the research: The aim of the study was to reveal multiple correlations between BNP levels and selected echocardiographic parameters of the left atrium in patients with permanent pacemakers. In the literature there are reports on the significance of BNP values and left atrial size in patients with permanent pacemakers. The results of the present study appear to be of value in the outpatient assessment of these patients. Material and methods: We analysed a group of 117 patients with permanent pacemakers (AAI/R 21 patients, DDD/R 59 patients, VVI/R 37 patients and 48 healthy volunteers serving as the control group. BNP measurements were performed on venous blood samples using Triage meters. The Simpson method and the ellipse method were used to assess the left atrium on echocardiography. Results: There was a significant correlation between BNP and maximum left atrial volume, minimum left atrial volume, and left atrial volume index in patients with AAI/R, DDD/R, and VVI/R pacemakers at 3 and 6 months after the implantation. Conclusions : In patients after implantation of permanent pacemakers there are correlations between BNP values and echocardiographic left atrial parameters, especially in patients with DDD/R pacemakers. Left atrial function improves in patients with DDD/R pacemakers. Pacemaker check-up should be extended to include BNP measurements and echocardiographic assessment of the left atrium.

Intraoperative Hemodynamic and Echocardiographic Measurements Associated With Severe Right Ventricular Failure After Left Ventricular Assist Device Implantation.

Science.gov (United States)

Gudejko, Michael D; Gebhardt, Brian R; Zahedi, Farhad; Jain, Ankit; Breeze, Janis L; Lawrence, Matthew R; Shernan, Stanton K; Kapur, Navin K; Kiernan, Michael S; Couper, Greg; Cobey, Frederick C

2018-06-05

Severe right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation increases morbidity and mortality. We investigated the association between intraoperative right heart hemodynamic data, echocardiographic parameters, and severe versus nonsevere RVF. A review of LVAD patients between March 2013 and March 2016 was performed. Severe RVF was defined by the need for a right ventricular mechanical support device, inotropic, and/or inhaled pulmonary vasodilator requirements for >14 days. From a chart review, the right ventricular failure risk score was calculated and right heart hemodynamic data were collected. Pulmonary artery pulsatility index (PAPi) [(pulmonary artery systolic pressure - pulmonary artery diastolic pressure)/central venous pressure (CVP)] was calculated for 2 periods: (1) 30 minutes before cardiopulmonary bypass (CPB) and (2) after chest closure. Echocardiographic data were recorded pre-CPB and post-CPB by a blinded reviewer. Univariate logistic regression models were used to examine the performance of hemodynamic and echocardiographic metrics. A total of 110 LVAD patients were identified. Twenty-five did not meet criteria for RVF. Of the remaining 85 patients, 28 (33%) met criteria for severe RVF. Hemodynamic factors associated with severe RVF included: higher CVP values after chest closure (18 ± 9 vs 13 ± 5 mm Hg; P = .0008) in addition to lower PAPi pre-CPB (1.2 ± 0.6 vs 1.7 ± 1.0; P = .04) and after chest closure (0.9 ± 0.5 vs 1.5 ± 0.8; P = .0008). Post-CPB echocardiographic findings associated with severe RVF included: larger right atrial diameter major axis (5.4 ± 0.9 vs 4.9 ± 1.0 cm; P = .03), larger right ventricle end-systolic area (22.6 ± 8.4 vs 18.5 ± 7.9 cm; P = .03), lower fractional area of change (20.2 ± 10.8 vs 25.9 ± 12.6; P = .04), and lower tricuspid annular plane systolic excursion (0.9 ± 0.2 vs 1.1 ± 0.3 cm; P = .008). Right ventricular failure risk score was not a significant predictor of

Fusion Imaging for Procedural Guidance.

Science.gov (United States)

Wiley, Brandon M; Eleid, Mackram F; Thaden, Jeremy J

2018-05-01

The field of percutaneous structural heart interventions has grown tremendously in recent years. This growth has fueled the development of new imaging protocols and technologies in parallel to help facilitate these minimally-invasive procedures. Fusion imaging is an exciting new technology that combines the strength of 2 imaging modalities and has the potential to improve procedural planning and the safety of many commonly performed transcatheter procedures. In this review we discuss the basic concepts of fusion imaging along with the relative strengths and weaknesses of static vs dynamic fusion imaging modalities. This review will focus primarily on echocardiographic-fluoroscopic fusion imaging and its application in commonly performed transcatheter structural heart procedures. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Identification of species and geographical strains of Sitophilus oryzae and Sitophilus zeamais using the visible/near-infrared hyperspectral imaging technique.

Science.gov (United States)

Cao, Yang; Zhang, Chaojie; Chen, Quansheng; Li, Yanyu; Qi, Shuai; Tian, Lin; Ren, YongLin

2015-08-01

Identifying stored-product insects is essential for granary management. Automated, computer-based classification methods are rapidly developing in many areas. A hyperspectral imaging technique could potentially be developed to identify stored-product insect species and geographical strains. This study tested and adapted the technique using four geographical strains of each of two insect species, the rice weevil and maize weevil, to collect and analyse the resultant hyperspectral data. Three characteristic images that corresponded to the dominant wavelengths, 505, 659 and 955 nm, were selected by multivariate image analysis. Each image was processed, and 22 morphological and textural features from regions of interest were extracted as the inputs for an identification model. We found the backpropagation neural network model to be the superior method for distinguishing between the insect species and geographical strains. The overall recognition rates of the classification model for insect species were 100 and 98.13% for the calibration and prediction sets respectively, while the rates of the model for geographical strains were 94.17 and 86.88% respectively. This study has demonstrated that hyperspectral imaging, together with the appropriate recognition method, could provide a potential instrument for identifying insects and could become a useful tool for identification of Sitophilus oryzae and Sitophilus zeamais to aid in the management of stored-product insects. © 2014 Society of Chemical Industry.

Predictors of Total Mortality and Echocardiographic Response for Cardiac Resynchronization Therapy: A Cohort Study

Directory of Open Access Journals (Sweden)

Guilherme Ferreira Gazzoni

2017-11-01

Full Text Available Abstract Background: Clinical studies demonstrate that up to 40% of patients do not respond to cardiac resynchronization therapy (CRT, thus, appropriate patient selection is critical to the success of CRT in heart failure. Objective: Evaluation of mortality predictors and response to CRT in the Brazilian scenario. Methods: Retrospective cohort study including patients submitted to CRT in a tertiary hospital in southern Brazil from 2008 to 2014. Survival was assessed through a database of the State Department of Health (RS. Predictors of echocardiographic response were evaluated using Poisson regression. Survival analysis was performed by Cox regression and Kaplan Meyer curves. A two-tailed p value less than 0.05 was considered statistically significant. Results: A total of 170 patients with an average follow-up of 1011 ± 632 days were included. The total mortality was 30%. The independent predictors of mortality were age (hazard ratio [HR] of 1.05, p = 0.027, previous acute myocardial infarction (AMI (HR of 2.17, p = 0.049 and chronic obstructive pulmonary disease (COPD (HR of 3.13, p = 0.015. The percentage of biventricular stimulation at 6 months was identified as protective factor of mortality ([HR] 0.97, p = 0.048. The independent predictors associated with the echocardiographic response were absence of mitral insufficiency, presence of left bundle branch block and percentage of biventricular stimulation. Conclusion: Mortality in patients submitted to CRT in a tertiary hospital was independently associated with age, presence of COPD and previous AMI. The percentage of biventricular pacing evaluated 6 months after resynchronizer implantation was independently associated with improved survival and echocardiographic response.

Computer-assisted determination of left ventricular endocardial borders reduces variability in the echocardiographic assessment of ejection fraction

Directory of Open Access Journals (Sweden)

Lindstrom Lena

2008-11-01

Full Text Available Abstract Background Left ventricular size and function are important prognostic factors in heart disease. Their measurement is the most frequent reason for sending patients to the echo lab. These measurements have important implications for therapy but are sensitive to the skill of the operator. Earlier automated echo-based methods have not become widely used. The aim of our study was to evaluate an automatic echocardiographic method (with manual correction if needed for determining left ventricular ejection fraction (LVEF based on an active appearance model of the left ventricle (syngo®AutoEF, Siemens Medical Solutions. Comparisons were made with manual planimetry (manual Simpson, visual assessment and automatically determined LVEF from quantitative myocardial gated single photon emission computed tomography (SPECT. Methods 60 consecutive patients referred for myocardial perfusion imaging (MPI were included in the study. Two-dimensional echocardiography was performed within one hour of MPI at rest. Image quality did not constitute an exclusion criterion. Analysis was performed by five experienced observers and by two novices. Results LVEF (%, end-diastolic and end-systolic volume/BSA (ml/m2 were for uncorrected AutoEF 54 ± 10, 51 ± 16, 24 ± 13, for corrected AutoEF 53 ± 10, 53 ± 18, 26 ± 14, for manual Simpson 51 ± 11, 56 ± 20, 28 ± 15, and for MPI 52 ± 12, 67 ± 26, 35 ± 23. The required time for analysis was significantly different for all four echocardiographic methods and was for uncorrected AutoEF 79 ± 5 s, for corrected AutoEF 159 ± 46 s, for manual Simpson 177 ± 66 s, and for visual assessment 33 ± 14 s. Compared with the expert manual Simpson, limits of agreement for novice corrected AutoEF was lower than for novice manual Simpson (0.8 ± 10.5 vs. -3.2 ± 11.4 LVEF percentage points. Calculated for experts and with LVEF (% categorized into Conclusion Corrected AutoEF reduces the variation in measurements compared with

Echocardiographic chamber quantification in a healthy Dutch population.

Science.gov (United States)

van Grootel, R W J; Menting, M E; McGhie, J; Roos-Hesselink, J W; van den Bosch, A E

2017-12-01

For accurate interpretation of echocardiographic measurements normative data are required, which are provided by guidelines. For this article, the hypothesis was that these cannot be extrapolated to the Dutch population, since in Dutch clinical practice often higher values are found, which may not be pathological but physiological. Therefore this study aimed to 1) obtain and propose normative values for cardiac chamber quantification in a healthy Dutch population and 2) determine influences of baseline characteristics on these measurements. Prospectively recruited healthy subjects, aged 20-72 years (at least 28 subjects per age decade, equally distributed for gender) underwent physical examination and 2D and 3D echocardiography. Both ventricles and atria were assessed and volumes were calculated. 147 subjects were included (age 44 ± 14 years, 50% female). Overall, feasibility was good for both linear and volumetric measurements. Linear and volumetric parameters were consistently higher than current guidelines recommend, while functional parameters were in line with the guidelines. This was more so in the older population. 3D volumes were higher than 2D volumes. Gender dependency was seen in all body surface area (BSA) corrected volumes and with increasing age, ejection fractions decreased. This study provides 2D and 3D echocardiographic reference ranges for both ventricles and atria derived from a healthy Dutch population. BSA indexed volumes are gender-dependent, age did not influence ventricular volumes and a rise in blood pressure was independently associated with increased right ventricular volumes. The higher volumes found may be indicative for the Dutch population being the tallest in the world.

Two-dimensional and Doppler echocardiographic findings in healthy non-sedated red-eared slider terrapins (Trachemys scripta elegans).

Science.gov (United States)

Poser, H; Russello, G; Zanella, A; Bellini, L; Gelli, D

2011-12-01

Echocardiographic evaluation was performed in six healthy young adult non-sedated terrapins (Trachemys scripta elegans). The best imaging quality was obtained through the right cervical window. Base-apex inflow and outflow views were recorded, ventricular size, ventricular wall thickness and ventricular outflow tract were measured, and fractional shortening was calculated. Pulsed-wave Doppler interrogation enabled the diastolic biphasic atrio-ventricular flow and the systolic ventricular outflow patterns to be recorded. The following Doppler-derived functional parameters were calculated: early diastolic (E) and late diastolic (A) wave peak velocities, E/A ratio, ventricular outflow systolic peak and mean velocities and gradients, Velocity-Time Integral, acceleration and deceleration times, and Ejection Time. For each parameter the mean, standard deviation and 95% confidence interval were calculated. Echocardiography resulted as a useful and easy-to-perform diagnostic tool in this poorly known species that presents difficulties during evaluation.

The Burden of Pulmonary Hypertension in Patients with Degenerative Mitral Valve Disease in Enugu South-East Nigeria: An Echocardiographic Based Study.

Science.gov (United States)

Ejim, E C; Oguanobi, N I

2016-01-01

Pulmonary hypertension is a common complication of degenerative mitral valve disease, and contributes significantly to both morbidity and mortality. The use of medications for reduction of pulmonary pressure in patients is not a common practice by most physicians in this part of the world because of the absence of data on pulmonary hypertension. The authors set out to find the prevalence of pulmonary hypertension in patients with degenerative mitral valve disease and to determine if there are gender differences in affectation. This will form a basis for future research on the management of pulmonary hypertension in sub-Saharan Africa. The echocardiographic records of 1390 patients carried out over a period of 4 years were retrospectively reviewed. The examinations were done with a Logic 500 MD echocardiographic machine. Tricuspid valve regurgitation velocity above 250 cm/s defined pulmonary hypertension. Data obtained included presence of degenerative mitral valve disease, pulmonary hypertension, age, and gender. A total of 1390 echocardiogram reports done at Conquest Medical Imaging, Enugu, from July 2009 to August 2013 were retrospectively reviewed. Degenerative mitral valve disease was noted in 18.7% of the patients, (259/1390) made up of 149 males and 110 females with a mean age of 68.3 (14.4) years. Pulmonary hypertension was present in 30% of the patients (78/259) and affected males more than females. Pulmonary hypertension is common in patients with degenerative mitral valve disease in Enugu, and affects males more than females.

Prognostic usefulness of repeated echocardiographic evaluation after acute myocardial infarction. TRACE Study Group. TRAndolapril Cardiac Evaluation

DEFF Research Database (Denmark)

Korup, E; Køber, L; Torp-Pedersen, C

1999-01-01

The prognostic value of repeated echocardiographic measurement of left ventricular function after acute myocardial infarction was evaluated. We found that repeated measurements of wall motion index in survivors of acute myocardial infarction, with no reinfarction, provide important prognostic...

The Value of 3D Printing Models of Left Atrial Appendage Using Real-Time 3D Transesophageal Echocardiographic Data in Left Atrial Appendage Occlusion: Applications toward an Era of Truly Personalized Medicine.

Science.gov (United States)

Liu, Peng; Liu, Rijing; Zhang, Yan; Liu, Yingfeng; Tang, Xiaoming; Cheng, Yanzhen

The objective of this study was to assess the clinical feasibility of generating 3D printing models of left atrial appendage (LAA) using real-time 3D transesophageal echocardiogram (TEE) data for preoperative reference of LAA occlusion. Percutaneous LAA occlusion can effectively prevent patients with atrial fibrillation from stroke. However, the anatomical structure of LAA is so complicated that adequate information of its structure is essential for successful LAA occlusion. Emerging 3D printing technology has the demonstrated potential to structure more accurately than conventional imaging modalities by creating tangible patient-specific models. Typically, 3D printing data sets are acquired from CT and MRI, which may involve intravenous contrast, sedation, and ionizing radiation. It has been reported that 3D models of LAA were successfully created by the data acquired from CT. However, 3D printing of the LAA using real-time 3D TEE data has not yet been explored. Acquisition of 3D transesophageal echocardiographic data from 8 patients with atrial fibrillation was performed using the Philips EPIQ7 ultrasound system. Raw echocardiographic image data were opened in Philips QLAB and converted to 'Cartesian DICOM' format and imported into Mimics® software to create 3D models of LAA, which were printed using a rubber-like material. The printed 3D models were then used for preoperative reference and procedural simulation in LAA occlusion. We successfully printed LAAs of 8 patients. Each LAA costs approximately CNY 800-1,000 and the total process takes 16-17 h. Seven of the 8 Watchman devices predicted by preprocedural 2D TEE images were of the same sizes as those placed in the real operation. Interestingly, 3D printing models were highly reflective of the shape and size of LAAs, and all device sizes predicted by the 3D printing model were fully consistent with those placed in the real operation. Also, the 3D printed model could predict operating difficulty and the

Usefulness of right ventricular and right atrial two-dimensional speckle tracking strain to predict late arrhythmic events in adult patients with repaired Tetralogy of Fallot.

Science.gov (United States)

Timóteo, Ana T; Branco, Luísa M; Rosa, Sílvia A; Ramos, Ruben; Agapito, Ana F; Sousa, Lídia; Galrinho, Ana; Oliveira, José A; Oliveira, Mário M; Ferreira, Rui C

2017-01-01

To determine whether right ventricular and/or atrial speckle tracking strain is associated with previous arrhythmic events in patients with repaired tetralogy of Fallot. We studied right ventricular and atrial strain in 100 consecutive patients with repaired tetralogy of Fallot referred for routine echocardiographic evaluation. Patients were divided into two groups, one with previous documentation of arrhythmias (n=26) and one without arrhythmias, in a median follow-up of 22 years. Patients with arrhythmias were older (pFallot, although a prospective study is required. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Echocardiographic parameters and survival in Chagas heart disease with severe systolic dysfunction.

Science.gov (United States)

Rassi, Daniela do Carmo; Vieira, Marcelo Luiz Campos; Arruda, Ana Lúcia Martins; Hotta, Viviane Tiemi; Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador

2014-03-01

Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p 70.71 mL/m2 were associated with a significant increase in mortality (log rank p < 0.0001). The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction.

Noninvasive Localization of Accessory Pathways in Patients with Wolff-Parkinson-White Syndrome: A Strain Imaging Study

Science.gov (United States)

Esmaeilzadeh, Maryam; Omran, Mohammad Taghi Salehi; Maleki, Majid; Haghjoo, Majid; Noohi, Feridoun; Haghighi, Zahra Ojaghi; Sadeghpour, Anita; Davari, Paridokht Nakhostin; Abkenar, Hooman Bakhshandeh

2013-01-01

Background: Noninvasive techniques for the localization of the accessory pathways (APs) might help guide mapping procedures and ablation techniques. We sought to examine the diagnostic accuracy of strain imaging for the localization of the APs in Wolff-Parkinson-White syndrome. Methods: We prospectively studied 25 patients (mean age = 32 ± 17 years, 58.3% men) with evidence of pre-excitation on electrocardiography (ECG). Electromechanical interval was defined as the time difference between the onset of delta wave and the onset of regional myocardial contraction. Time differences between the onset of delta wave (δ) and the onset of regional myocardial contraction (δ-So), peak systolic motion (δ-Sm), regional strain (δ-ε), peak strain (δ-εp), and peak strain rate (δ-SRp) were measured. Results: There was a significant difference between time to onset of delta wave to onset of peak systolic motion (mean ± SD) in the AP location (A) and normal segments (B) versus that in the normal volunteers (C) [A: (57.08 ± 23.88 msec) vs. B: (75.20 ± 14.75) vs. C: (72.9 0 ± 11.16); p value (A vs. B) = 0.004 and p value (A vs. C) = 0.18] and [A: (49.17 ± 35.79) vs. B: (67.60 ± 14.51) vs. C: (67.40 ± 6.06 msec); p value (A vs. B) < 0.001 and p value (A vs. C) = 0.12, respectively]. Conclusion: Our study showed that strain imaging parameters [(δ-So) and (δ-Strain)] are superior to the ECG in the localization of the APs (84% vs. 76%). PMID:23967027

Coronary artery size and origin imaging in children: a comparative study of MRI and trans-thoracic echocardiography

International Nuclear Information System (INIS)

Hussain, Tarique; Mathur, Sujeev; Peel, Sarah A.; Valverde, Israel; Bilska, Karolina; Henningsson, Markus; Botnar, Rene M.; Simpson, John; Greil, Gerald F.

2015-01-01

The purpose of this study was to see how coronary magnetic resonance angiography (CMRA) compared to echocardiography for the detection of coronary artery origins and to compare CMRA measurements for coronary dimensions in children with published echocardiographic reference values. Enrolled patients underwent dual cardiac phase CMRA and echocardiography under the same anesthetic. Echocardiographic measurements of the right coronary artery (RCA), left anterior descending (LAD) and left main (LM) were made. CMRA dimensions were assessed manually at the same points as the echocardiographic measurements. The number of proximal LAD branches imaged was also recorded in order to give an estimate of distal coronary tree visualization. Fifty patients (24 boys, mean age 4.0 years (range 18 days to 18 years)) underwent dual-phase CMRA. Coronary origins were identified in 47/50 cases for CMRA (remaining 3 were infants aged 3, 9 and 11 months). In comparison, origins were identified in 41/50 cases for echo (remaining were all older children). CMRA performed better than echocardiography in terms of distal visualization of the coronary tree (median 1 LAD branch vs. median 0; p = 0.001). Bland-Altman plots show poor agreement between echocardiography and CMRA for coronary measurements. CMRA measurements did vary according to cardiac phase (systolic mean 1.90, s.d. 0.05 mm vs. diastolic mean 1.84, s.d. 0.05 mm; p = 0.002). Dual-phase CMRA has an excellent (94 %) success rate for the detection of coronary origins in children. Newborn infants remain challenging and echocardiography remains the accepted imaging modality for this age group. Echocardiographic reference ranges are not applicable to CMRA measurements as agreement was poor between modalities. Future coronary reference values, using any imaging modality, should quote the phase in which it was measured

Nuclear magnetic resonance imaging in patients with hypertrophic and dilated cardiomyopathy

International Nuclear Information System (INIS)

Boisvieux, A.

1987-01-01

Patients with hypertrophic and dilated cardiomyopathy and normal subjects were investigated with nuclear magnetic resonance imaging. To evaluate the NMR scanner possibilities, the results were compared with the echocardiographic investigation of the same patients. The capabilities of NMR imaging to provide information about intracardiac anatomy are emphasized. This study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of the techniques used to obtain NMR images and a review of the clinical use of NMR imaging for cardiac diagnosis [fr

Digital Image Correlation of 2D X-ray Powder Diffraction Data for Lattice Strain Evaluation

Science.gov (United States)

Zhang, Hongjia; Sui, Tan; Daisenberger, Dominik; Fong, Kai Soon

2018-01-01

High energy 2D X-ray powder diffraction experiments are widely used for lattice strain measurement. The 2D to 1D conversion of diffraction patterns is a necessary step used to prepare the data for full pattern refinement, but is inefficient when only peak centre position information is required for lattice strain evaluation. The multi-step conversion process is likely to lead to increased errors associated with the ‘caking’ (radial binning) or fitting procedures. A new method is proposed here that relies on direct Digital Image Correlation analysis of 2D X-ray powder diffraction patterns (XRD-DIC, for short). As an example of using XRD-DIC, residual strain values along the central line in a Mg AZ31B alloy bar after 3-point bending are calculated by using both XRD-DIC and the conventional ‘caking’ with fitting procedures. Comparison of the results for strain values in different azimuthal angles demonstrates excellent agreement between the two methods. The principal strains and directions are calculated using multiple direction strain data, leading to full in-plane strain evaluation. It is therefore concluded that XRD-DIC provides a reliable and robust method for strain evaluation from 2D powder diffraction data. The XRD-DIC approach simplifies the analysis process by skipping 2D to 1D conversion, and opens new possibilities for robust 2D powder diffraction data analysis for full in-plane strain evaluation. PMID:29543728

Digital Image Correlation of 2D X-ray Powder Diffraction Data for Lattice Strain Evaluation

Directory of Open Access Journals (Sweden)

Hongjia Zhang

2018-03-01

Full Text Available High energy 2D X-ray powder diffraction experiments are widely used for lattice strain measurement. The 2D to 1D conversion of diffraction patterns is a necessary step used to prepare the data for full pattern refinement, but is inefficient when only peak centre position information is required for lattice strain evaluation. The multi-step conversion process is likely to lead to increased errors associated with the ‘caking’ (radial binning or fitting procedures. A new method is proposed here that relies on direct Digital Image Correlation analysis of 2D X-ray powder diffraction patterns (XRD-DIC, for short. As an example of using XRD-DIC, residual strain values along the central line in a Mg AZ31B alloy bar after 3-point bending are calculated by using both XRD-DIC and the conventional ‘caking’ with fitting procedures. Comparison of the results for strain values in different azimuthal angles demonstrates excellent agreement between the two methods. The principal strains and directions are calculated using multiple direction strain data, leading to full in-plane strain evaluation. It is therefore concluded that XRD-DIC provides a reliable and robust method for strain evaluation from 2D powder diffraction data. The XRD-DIC approach simplifies the analysis process by skipping 2D to 1D conversion, and opens new possibilities for robust 2D powder diffraction data analysis for full in-plane strain evaluation.

Echocardiographic identification of ventricular septal rupture caused by acute stent thrombosis.

Science.gov (United States)

Garg, Scot; Bourantas, Christos V; Thackray, Simon; Alamgir, Mohamed F

2010-05-01

Coronary stenting is an increasingly common procedure. Complications are rare. However, when they do occur, they often require urgent invasive treatment. Investigations that are critical for establishing a diagnosis as well as such guide treatment as a detailed assessment of myocardial morphology and function using transthoracic echocardiography may be overlooked in the haste to treat the patient. We present a case report of subacute drug-eluting stent thrombosis in which a meticulous echocardiographic examination allowed the identification of a ventricular septal rupture, which ultimately modified treatment.

Rapid estimation of left ventricular ejection fraction in acute myocardial infarction by echocardiographic wall motion analysis

DEFF Research Database (Denmark)

Berning, J; Rokkedal Nielsen, J; Launbjerg, J

1992-01-01

Echocardiographic estimates of left ventricular ejection fraction (ECHO-LVEF) in acute myocardial infarction (AMI) were obtained by a new approach, using visual analysis of left ventricular wall motion in a nine-segment model. The method was validated in 41 patients using radionuclide...

Standardised imaging technique for guided M-mode and Doppler echocardiography in the horse.

Science.gov (United States)

Long, K J; Bonagura, J D; Darke, P G

1992-05-01

Eighteen echocardiographic images useful for diagnostic imaging, M-mode echocardiography, and Doppler echocardiography of the equine heart were standardised by relating the position of the axial beam to various intracardiac landmarks. The transducer orientation required for each image was recorded in 14 adult horses by describing the degree of sector rotation and the orientation of the axial beam relative to the thorax. Repeatable images could be obtained within narrow limits of angulation and rotation for 14 of the 18 standardised images evaluated. Twenty-seven National Hunt horses were subsequently examined using this standardised technique. Selected cardiac dimensions were measured from two-dimensional and guided M-mode studies. Satisfactory results were achieved in 26 of the 27 horses. There was no linear correlation between any of the measured cardiac values and bodyweight. There was no significant difference between measurements taken from the left and the right hemithorax. Six horses were imaged on three consecutive days to assess the repeatability of the measurements. No significant difference was found between measurements obtained on different days. This study demonstrates a method for standardised echocardiographic evaluation of the equine heart that is repeatable, valuable for teaching techniques of equine echocardiography, applicable for diagnostic imaging and quantification of cardiac size, and useful for the evaluation of blood-flow patterns by Doppler ultrasound.

Lagrangian displacement tracking using a polar grid between endocardial and epicardial contours for cardiac strain imaging.

Science.gov (United States)

Ma, Chi; Varghese, Tomy

2012-04-01

Accurate cardiac deformation analysis for cardiac displacement and strain imaging over time requires Lagrangian description of deformation of myocardial tissue structures. Failure to couple the estimated displacement and strain information with the correct myocardial tissue structures will lead to erroneous result in the displacement and strain distribution over time. Lagrangian based tracking in this paper divides the tissue structure into a fixed number of pixels whose deformation is tracked over the cardiac cycle. An algorithm that utilizes a polar-grid generated between the estimated endocardial and epicardial contours for cardiac short axis images is proposed to ensure Lagrangian description of the pixels. Displacement estimates from consecutive radiofrequency frames were then mapped onto the polar grid to obtain a distribution of the actual displacement that is mapped to the polar grid over time. A finite element based canine heart model coupled with an ultrasound simulation program was used to verify this approach. Segmental analysis of the accumulated displacement and strain over a cardiac cycle demonstrate excellent agreement between the ideal result obtained directly from the finite element model and our Lagrangian approach to strain estimation. Traditional Eulerian based estimation results, on the other hand, show significant deviation from the ideal result. An in vivo comparison of the displacement and strain estimated using parasternal short axis views is also presented. Lagrangian displacement tracking using a polar grid provides accurate tracking of myocardial deformation demonstrated using both finite element and in vivo radiofrequency data acquired on a volunteer. In addition to the cardiac application, this approach can also be utilized for transverse scans of arteries, where a polar grid can be generated between the contours delineating the outer and inner wall of the vessels from the blood flowing though the vessel.

Effect of gender on echocardiographic outcomes of patients presenting with mitral stenosis at a tertiary care hospital

International Nuclear Information System (INIS)

Saeed, M.; Haq, I.U.

2011-01-01

To assess the gender-based differences in the echocardiographic outcomes of patients with mitral stenosis presenting at a tertiary care hospital and the clinical implications of such differences. Methods: A total of 90 echocardiographs of both men and women (aged=15 years) having mitral valve area (MVA) less than 4 cm/sup 2/ were assessed. In addition to MVA, pressure half time and left atrial diameter (LAD) of the patients was also recorded. Other co-existing valvular lesions were also assessed in addition to mitral stenosis. Statistical analysis was done using SPSS-17. Results: A higher prevalence of mitral stenosis (MS) was found in women than men (76.66% vs 24.44%). Men were having more severe mitral stenosis as compared to women (MVA=1.19 cm/sup 2/ vs 1.32 cm/sup 2/). This also resulted in significantly higher left atrial dilatation in males as compared to women (45.09 vs 41.75, p=0.0422). Most of the patients had other coexisting valvular lesions and isolated MS was rare. However, men had a predominance of aortic stenosis along with mitral stenosis (27% vs 4%, p=0.0059) whereas women had a higher prevalence of mitral regurgitation along with mitral stenosis than the men (65% vs 36%, p=0.0258). Conclusion: There were certain significant differences in echocardiographic outcomes of patients based upon their gender. A gender-specific management approach towards the patients with mitral stenosis is essential to have better outcome. (author)

ECHOCARDIOGRAPHIC FINDINGS OF BIDIMENSIONAL MODE, M-MODE, AND DOPPLER OF CLINICALLY NORMAL BLACK-RUMPED AGOUTI (DASYPROCTA PRYMNOLOPHA, WAGLER 1831).

Science.gov (United States)

Diniz, Anaemilia das Neves; Pessoa, Gerson Tavares; da Silva Moura, Laecio; de Sousa, André Braga; Sousa, Francisco das Chagas Araújo; de Sá Rodrigues, Renan Paraguassu; da Silva Barbosa, Maria Angélica Parente; de Almeida, Hatawa Melo; Freire, Larisse Danielle Silva; Sanches, Marina Pinto; Júnior, Antônio Augusto Nascimento Machado; Guerra, Porfírio Candanedo; Neves, Willams Costa; de Sousa, João Macedo; Bolfer, Luiz; Giglio, Robson Fortes; Alves, Flávio Ribeiro

2017-06-01

The black-rumped agouti ( Dasyprocta prymnolopha , Wagler 1831) is currently under intense ecologic pressure, which has resulted in its disappearance from some regions of Brazil. Echocardiography is widely used in veterinary medicine but it is not yet part of the clinical routine for wild animals. The objective of the present study was to assess the applicability of the echocardiographic exam in nonanesthetized agouti and to establish normal reference values for echocardiographic measurements in bidimensional mode (2D), M-mode, and Doppler for this species, and a lead II electrocardiogram was simultaneously recorded. Twenty agouti were used in this study. All the echocardiographic measurements were positively correlated with weight (P 0.05). Blood flow velocities in the pulmonary and aortic artery ranged from 67.32-71.28 cm/sec and 79.22-101.84 cm/sec, respectively. The isovolumic relaxation time was assessed in all the animals and ranged from 38.5 to 56.6 ms. The maximum value for the nonfused E and A waves and the Et and At waves was 158 beats/min for both. The results obtained for the morphologic and heart hemodynamic measurements can guide future studies and help in the clinical management of these animals in captivity.

A meta-analysis of echocardiographic measurements of the left heart for the development of normative reference ranges in a large international cohort

DEFF Research Database (Denmark)

Møgelvang, Rasmus

2014-01-01

, from multiple studies around the world. METHODS AND RESULTS: The Echocardiographic Normal Ranges Meta-Analysis of the Left heart (EchoNoRMAL) collaboration was established and population-based data sets of echocardiographic measurements combined to perform an individual person data meta-analysis. Data...... from 43 studies were received, representing 51 222 subjects, of which 22 404 adults aged 18-80 years were without clinical cardiovascular or renal disease, hypertension or diabetes. Quantile regression or an appropriate parametric regression method will be used to derive reference values at the 5th...

Echocardiographic evaluation of the heart repercussions of different sport modalities in athletes of high yield

International Nuclear Information System (INIS)

Chaves, Angel Maria; Melo, German; Conde, Carlos Arturo; Vesga, Boris Eduardo

2002-01-01

The paper compares anthropometry and echocardiographic changes secondary to longest training in elite athletes. They were not differences in the ejection fraction, stroke volume and systolic wall stress. Differences were found in septum thickness, posterior wall thickness in dynamic and combined groups. This finding suggest morphological changes similar to left ventricular hypertrophy

Rationale and Design of the Echocardiographic Study of Hispanics/Latinos (ECHO-SOL).

Science.gov (United States)

Rodriguez, Carlos J; Dharod, Ajay; Allison, Matthew A; Shah, Sanjiv J; Hurwitz, Barry; Bangdiwala, Shrikant I; Gonzalez, Franklyn; Kitzman, Dalane; Gillam, Linda; Spevack, Daniel; Dadhania, Rupal; Langdon, Sarah; Kaplan, Robert

2015-01-01

Information regarding the prevalence and determinants of cardiac structure and function (systolic and diastolic) among the various Hispanic background groups in the United States is limited. The Echocardiographic Study of Latinos (ECHO-SOL) ancillary study recruited 1,824 participants through a stratified-sampling process representative of the population-based Hispanic Communities Health Study - Study of Latinos (HCHS-SOL) across four sites (Bronx, NY; Chicago, Ill; San Diego, Calif; Miami, Fla). The HCHS-SOL baseline cohort did not include an echo exam. ECHO-SOL added the echocardiographic assessment of cardiac structure and function to an array of existing HCHS-SOL baseline clinical, psychosocial, and socioeconomic data and provides sufficient statistical power for comparisons among the Hispanic subgroups. Standard two-dimensional (2D) echocardiography protocol, including M-mode, spectral, color and tissue Doppler study was performed. The main objectives were to: 1) characterize cardiac structure and function and its determinants among Hispanics and Hispanic subgroups; and 2) determine the contributions of specific psychosocial factors (acculturation and familismo) to cardiac structure and function among Hispanics. We describe the design, methods and rationale of currently the largest and most comprehensive study of cardiac structure and function exclusively among US Hispanics. ECHO-SOL aims to enhance our understanding of Hispanic cardiovascular health as well as help untangle the relative importance of Hispanic subgroup heterogeneity and sociocultural factors on cardiac structure and function.

Improving appropriate use of echocardiography and single-photon emission computed tomographic myocardial perfusion imaging: a continuous quality improvement initiative.

Science.gov (United States)

Johnson, Thomas V; Rose, Geoffrey A; Fenner, Deborah J; Rozario, Nigel L

2014-07-01

Appropriate use criteria for cardiovascular imaging have been published, but compliance in practice has been incomplete, with persistent high rates of inappropriate use. The aim of this study was to show the efficacy of a continuous quality improvement (CQI) initiative to favorably influence the appropriate use of outpatient transthoracic echocardiography and single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (MPI) in a large cardiovascular practice. In this prospective study, a multiphase CQI initiative was implemented, and its impact on ordering patterns for outpatient transthoracic echocardiography and SPECT MPI was assessed. Between November and December 2010, a baseline analysis of the application of appropriate use criteria to indications for outpatient transthoracic echocardiographic studies (n = 203) and SPECT MPI studies (n = 205) was performed, with studies categorized as "appropriate," "inappropriate," "uncertain," or "unclassified." The CQI initiative was then begun, with (1) clinician education, including didactic lectures and case-based presentations with audience participation; (2) system changes in ordering processes, with redesigned image ordering forms; and (3) peer review and feedback. A follow-up analysis was then performed between June and August 2012, with categorization of indications for transthoracic echocardiographic studies (n = 206) and SPECT MPI studies (n = 206). At baseline, 73.9% of echocardiographic studies were categorized as appropriate, 16.7% as inappropriate, 5.9% as uncertain, and 3.4% as unclassified. Similarly, for SPECT MPI studies 71.7% were categorized as appropriate, 18.5% as inappropriate, 7.8% as uncertain, and 1.9% as unclassified. Separate analysis of the two most important categories, appropriate and inappropriate, demonstrated a significant improvement after the CQI initiative, with a 63% reduction in inappropriate echocardiographic studies (18.5% vs 6.9%, P = .0010) and a 46% reduction

Retrograde catheterisation vs. Doppler echocardiographic evaluation of aortic stenosis--a survey of contemporary UK practice.

Science.gov (United States)

Fazal, Iftikhar A; Alfakih, Khaled; Wilcox, Robert G; Walsh, John T

2009-05-01

Aortic stenosis (AS) is the most common indication for valve surgery. Recent data suggested an increased risk of cerebral emboli when the aortic valve is crossed to obtain 'pull-back' gradient. We conducted a large questionnaire based study to evaluate current practice in the assessment of aortic valve gradient amongst cardiologists and the preferences of cardiac surgeons in the UK. E-mail questionnaires were sent to 645 (72%) UK consultant cardiologists and to 198 (92%) UK consultant cardiac surgeons. 232 cardiologists and 52 cardiac surgeons responded. 53% of cardiologists routinely attempt to cross the valve in moderate AS while only 23% do so in severe AS. 38% of cardiologists in the age group '50+ years' cross the valve in severe AS compared to 13% in the age group '30-40 years'. Common reasons given for crossing a stenosed valve included 'to verify the echocardiographic gradient' (85%) and 'maintaining skill' (24%). 64% of cardiologists have changed their views on the necessity of crossing the valve in the last ten years. Although the majority appreciate the increased risk of crossing the valve only 18% of patients are consented differently if crossing the valve is planned. 26% of cardiac surgeons prefer the valve to be crossed to provide information on 'pull-back' gradient, 32% for LV function assessment and 14% to confirm MV competence. 92% would accept echocardiographic data alone if both the gradient and aortic valve area were available and considered correct. Our survey found that the practice of crossing the aortic valve has changed in the last 10 years and that younger consultant cardiologists are less likely to cross the aortic valve. Increasing confidence in echocardiographic data and potential complications of crossing the valve are implicated. 92% of cardiac surgeons do not require the valve to be crossed if the echo data is considered accurate.

Total average diastolic longitudinal displacement by colour tissue doppler imaging as an assessment of diastolic function

DEFF Research Database (Denmark)

de Knegt, Martina Chantal; Biering-Sørensen, Tor; Søgaard, Peter

2016-01-01

BACKGROUND: The current method for a non-invasive assessment of diastolic dysfunction is complex with the use of algorithms of many different echocardiographic parameters. Total average diastolic longitudinal displacement (LD), determined by colour tissue Doppler imaging (TDI) via the measurement...

[Spongy cardiomyopathy in an elderly woman. Echocardiographic description].

Science.gov (United States)

Canale, Jesús; Cortés Lawrenz, Jorge; Moreno Valenzuela, Francisco Germán

2005-01-01

Isolated left ventricular noncompaction, also known as spongy myocardium or spongy cardiomyopathy, is a recently described congenital disease caused by an arrest in the left ventricular myocardial embriogenesis that makes the ventricular wall to persist thickened with multiple trabecular formations and deep sinusoidal recesses. It is clinically characterized by heart failure, cardiac arrhythmia and systemic embolic events. Most of the affected subjects are detected during childhood or adolescence, others in the adult life but very few elderly patients have been reported in the worldwide medical literature. We here report the case of a 75-year-old woman that is one of the oldest patients ever reported, whose clinical picture and echocardiographic findings are typical of this modality of cardiomyopathy. We do comments on this case in regard to the most relevant facts that appear in the limited medical literature about this interesting disease.

Chronic valvular disease: correlation between clinical, electrocardiographic, radiographic and echocardiographic aspects in dogs

International Nuclear Information System (INIS)

Soares, E.C.; Larsson, M.H.M.A.; Yamato, R.J.

2005-01-01

Echocardiographic aspects of chronic mitral valvular disease were studied and compared to physical, radiographic and electrocardiographic aspects. Seventy dogs were used, and clinical examination, thoracic radiography, electrocardiogram and echocardiogram were performed. Correlations between regurgitation severity with cardiac failure functional class and murmur intensity were observed. The electrocardiogram showed a low sensibility in detecting cardiac chamber enlargement, caused by mitral regurgitation. All the dogs with severe mitral regurgitation showed cardiomegaly according to thoracic radiographies

Clinical and echocardiographic characteristics associated with the evolution of the ductus arteriosus in the neonate with birth weight lower than 1,500g.

Science.gov (United States)

Visconti, Luiza Fortunato; Morhy, Samira Saady; Deutsch, Alice D'Agostini; Tavares, Gláucia Maria Penha; Wilberg, Tatiana Jardim Mussi; Rossi, Felipe de Souza

2013-01-01

To identify clinical and echocardiographic parameters associated with the evolution of the ductus arteriosus in neonates with birth weight lower than 1,500g. Retrospective study of 119 neonates in which clinical parameters (Prenatal: maternal age, risk of infection and chorioamnionitis, use of corticosteroid, mode of delivery and gestational age. Perinatal: weight, Apgar score, gender and birth weight/gestational age classification; Postnatal: use of surfactant, sepsis, fluid intake, heart murmur, heart rate, precordial movement and pulses, use of diuretics, oxygenation index, desaturation/apnea, ventilatory support, food intolerance, chest radiography, renal function, hemodynamic instability, and metabolic changes) and echocardiographic parameters (ductus arteriosus diameter, ductus arteriosus/weight ratio, left atrium/ aorta ratio, left ventricular diastolic diameter, and transductal flow direction, pattern and velocity) were analyzed. The clinical and echocardiographic parameters analyzed were considered statistically significant when ppatent ductus arteriosus was 61.3%; 56 received treatment (46 pharmacological and 10 surgical treatment), 11 had spontaneous closure, 4 died, and 2 were discharged with patent ductus arteriosus. A higher incidence of chorioamnionitis, use of surfactant, lower weight and gestational age, sepsis, heart murmur, ventilatory support and worse oxygenation indices were observed in the neonates receiving treatment. The group with spontaneous closure had a smaller ductus arteriosus diameter, lower ductus arteriosus/weight ratio, and higher transductal flow velocity. Based on clinical and echocardiographic parameters, the neonates with spontaneous closure of the ductus arteriosus could be differentiated from those who required treatment.

The reliability of echocardiographic left ventricular wall motion index to identify high-risk patients for multicenter studies

DEFF Research Database (Denmark)

Gislason, Gunnar H; Gadsbøll, Niels; Quinones, Miguel A

2006-01-01

that were screened for inclusion into the DIAMOND-CHF and DIAMOND-MI trials were reevaluated by an external expert echocardiographer. WMI was calculated using the 16-segment LV model. RESULTS: The external echocardiographer systematically found lower values of WMI than the core laboratory. The average...... difference in WMI was 0.18 (SD: 0.33) in the DIAMOND-CHF trial and 0.09 (SD: 0.33) in the DIAMOND-MI trial. The difference in WMI exceeded 0.33 in 34% of the patients in both trials. The cutoff value for inclusion into the DIAMOND trials was WMI ... overall agreement for identifying patients with severe impairment of LV function. This not only underscores the value of LV-WMI as a useful tool for selecting high-risk patients to be included in multicenter studies but also serves to warn against the use of rigid cutoff values for WMI in the treatment...

submitter Digital Image Correlation of 2D X-ray Powder Diffraction Data for Lattice Strain Evaluation

CERN Document Server

Zhang, Hongjia; Salvati, Enrico; Daisenberger, Dominik; Lunt, Alexander J G; Fong, Kai Soon; Song, Xu; Korsunsky, Alexander M

2018-01-01

High energy 2D X-ray powder diffraction experiments are widely used for lattice strain measurement. The 2D to 1D conversion of diffraction patterns is a necessary step used to prepare the data for full pattern refinement, but is inefficient when only peak centre position information is required for lattice strain evaluation. The multi-step conversion process is likely to lead to increased errors associated with the ‘caking’ (radial binning) or fitting procedures. A new method is proposed here that relies on direct Digital Image Correlation analysis of 2D X-ray powder diffraction patterns (XRD-DIC, for short). As an example of using XRD-DIC, residual strain values along the central line in a Mg AZ31B alloy bar after 3-point bending are calculated by using both XRD-DIC and the conventional ‘caking’ with fitting procedures. Comparison of the results for strain values in different azimuthal angles demonstrates excellent agreement between the two methods. The principal strains and directions are calculated...

Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by three-dimensional digital image correlation

Directory of Open Access Journals (Sweden)

H. Munoz

2017-08-01

Full Text Available The complete stress–strain characteristics of sandstone specimens were investigated in a series of quasi-static monotonic uniaxial compression tests. Strain patterns development during pre- and post-peak behaviours in specimens with different aspect ratios was also examined. Peak stress, post-peak portion of stress–strain, brittleness, characteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect ratio. Strain patterns of the rocks were obtained by applying three-dimensional (3D digital image correlation (DIC technique. Unlike conventional strain measurement using strain gauges attached to specimen, 3D DIC allowed not only measuring large strains, but more importantly, mapping the development of field strain throughout the compression test, i.e. in pre- and post-peak regimes. Field strain development in the surface of rock specimen suggests that strain starts localising progressively and develops at a lower rate in pre-peak regime. However, in post-peak regime, strains increase at different rates as local deformations take place at different extents in the vicinity and outside the localised zone. The extent of localised strains together with the rate of strain localisation is associated with the increase in rate of strength degradation. Strain localisation and local inelastic unloading outside the localised zone both feature post-peak regime.

Strain Analysis of Stretched Tourmaline Crystals Using ImageJ, Microsoft Excel and PowerPoint

Science.gov (United States)

Bosbyshell, H.

2012-12-01

This poster describes an undergraduate structural geology lab exercise utilizing the Mohr's circle diagram for finite strain, constructed using measurements obtained from stretched tourmaline crystals. A small building housing HVAC equipment at the south end of West Chester University's Recitation Hall (itself made of serpentinite) is constructed of early-Cambrian Chickies Quartzite. Stretched tourmaline crystals, with segments joined by fibrous quartz, are visible on many surfaces (presumably originally bedding). While the original orientation of any stone is unknown, these rocks provide an opportunity for a short field exercise during a two-hour lab period and a great base for conducting strain analysis. It is always fun to ask how many in the class have ever noticed the tourmaline (few have). Students take photos using their cell phones or cameras. Since strain is a ratio the absolute size of the tourmaline crystals is immaterial. Nonetheless, this is a good opportunity to remind students of the importance of including a scale in their photographs. The photos are opened in ImageJ and the line tool is used to determine the original and final lengths of selected crystals. Students calculate strain parameters using Microsoft Excel. Then, we use Adobe Illustrator or the drafting capabilities of Microsoft PowerPoint 2010 to follow Ramsay and Huber's techniques using a Mohr's circle construction to determine the finite strain ellipse. If a stretching direction can be estimated, elongation of two crystals is all that is required to determine the strain ratio. If no stretching direction is apparent, three crystals are required for a more complicated analysis that allows for determination of the stretching direction, as well as the strain ratio.

Patient selection, echocardiographic screening and treatment strategies for interventional tricuspid repair using the edge-to-edge repair technique.

Science.gov (United States)

Hausleiter, Jörg; Braun, Daniel; Orban, Mathias; Latib, Azeem; Lurz, Philipp; Boekstegers, Peter; von Bardeleben, Ralph Stephan; Kowalski, Marek; Hahn, Rebecca T; Maisano, Francesco; Hagl, Christian; Massberg, Steffen; Nabauer, Michael

2018-04-24

Severe tricuspid regurgitation (TR) has long been neglected despite its well known association with mortality. While surgical mortality rates remain high in isolated tricuspid valve surgery, interventional TR repair is rapidly evolving as an alternative to cardiac surgery in selected patients at high surgical risk. Currently, interventional edge-to-edge repair is the most frequently applied technique for TR repair even though the device has not been developed for this particular indication. Due to the inherent differences in tricuspid and mitral valve anatomy and pathology, percutaneous repair of the tricuspid valve is challenging due to a variety of factors including the complexity and variability of tricuspid valve anatomy, echocardiographic visibility of the valve leaflets, and device steering to the tricuspid valve. Furthermore, it remains to be clarified which patients are suitable for a percutaneous tricuspid repair and which features predict a successful procedure. On the basis of the available experience, we describe criteria for patient selection including morphological valve features, a standardized process for echocardiographic screening, and a strategy for clip placement. These criteria will help to achieve standardization of valve assessment and the procedural approach, and to further develop interventional tricuspid valve repair using either currently available devices or dedicated tricuspid edge-to-edge repair devices in the future. In summary, this manuscript will provide guidance for patient selection and echocardiographic screening when considering edge-to-edge repair for severe TR.

Which Criteria are More Valuable in Defining Hemodynamic Significance of Patent Ductus Arteriosus in Premature Infants? Respiratory or Echocardiographic?

Directory of Open Access Journals (Sweden)

İrfan Oğuz Şahin

2017-03-01

Full Text Available Aim: Patent ductus arteriosus (PDA is a frequent health problem in premature infants. Pharmacologic closure is recommended only for hemodynamically significant PDA (hsPDA that is defined according to the clinical and echocardiographic criteria. The aim of this study was to explore the value of commonly used criteria in defining hsPDA and predicting the required number of courses of ibuprofen treatment to close PDA in premature infants. Methods: Sixty premature infants with a gestational age of ≤33 weeks were evaluated prospectively. Clinical and echocardiographic criteria [O2 requirement, ductus diameter (DD and left atrial-to-aortic root diameter ratio (LA:Ao] were used to define hsPDA. Clinical improvement after pharmacologic closure of PDA and association between the criteria and required number of ibuprofen courses were investigated. Results: O2 requirement decreased by PDA closure but was not different between patients with hsPDA and the others with PDA. Also, O2 requirement was not found to be associated with required number of ibuprofen courses. DD and LA:Ao were greater in patients with hsPDA. DD was found to be associated with required number of courses of ibuprofen treatment. Conclusion: Although there was an improvement in O2 requirement with PDA closure, echocardiographic criteria were found to be more valuable in defining hsPDA. DD should also be used to estimate the duration of treatment.

FAST (Four chamber view And Swing Technique) Echo: a Novel and Simple Algorithm to Visualize Standard Fetal Echocardiographic Planes

Science.gov (United States)

Yeo, Lami; Romero, Roberto; Jodicke, Cristiano; Oggè, Giovanna; Lee, Wesley; Kusanovic, Juan Pedro; Vaisbuch, Edi; Hassan, Sonia S.

2010-01-01

Objective To describe a novel and simple algorithm (FAST Echo: Four chamber view And Swing Technique) to visualize standard diagnostic planes of fetal echocardiography from dataset volumes obtained with spatiotemporal image correlation (STIC) and applying a new display technology (OmniView). Methods We developed an algorithm to image standard fetal echocardiographic planes by drawing four dissecting lines through the longitudinal view of the ductal arch contained in a STIC volume dataset. Three of the lines are locked to provide simultaneous visualization of targeted planes, and the fourth line (unlocked) “swings” through the ductal arch image (“swing technique”), providing an infinite number of cardiac planes in sequence. Each line generated the following plane(s): 1) Line 1: three-vessels and trachea view; 2) Line 2: five-chamber view and long axis view of the aorta (obtained by rotation of the five-chamber view on the y-axis); 3) Line 3: four-chamber view; and 4) “Swing” line: three-vessels and trachea view, five-chamber view and/or long axis view of the aorta, four-chamber view, and stomach. The algorithm was then tested in 50 normal hearts (15.3 – 40 weeks of gestation) and visualization rates for cardiac diagnostic planes were calculated. To determine if the algorithm could identify planes that departed from the normal images, we tested the algorithm in 5 cases with proven congenital heart defects. Results In normal cases, the FAST Echo algorithm (3 locked lines and rotation of the five-chamber view on the y-axis) was able to generate the intended planes (longitudinal view of the ductal arch, pulmonary artery, three-vessels and trachea view, five-chamber view, long axis view of the aorta, four-chamber view): 1) individually in 100% of cases [except for the three-vessel and trachea view, which was seen in 98% (49/50)]; and 2) simultaneously in 98% (49/50). The “swing technique” was able to generate the three-vessels and trachea view, five

Four-chamber view and 'swing technique' (FAST) echo: a novel and simple algorithm to visualize standard fetal echocardiographic planes.

Science.gov (United States)

Yeo, L; Romero, R; Jodicke, C; Oggè, G; Lee, W; Kusanovic, J P; Vaisbuch, E; Hassan, S

2011-04-01

To describe a novel and simple algorithm (four-chamber view and 'swing technique' (FAST) echo) for visualization of standard diagnostic planes of fetal echocardiography from dataset volumes obtained with spatiotemporal image correlation (STIC) and applying a new display technology (OmniView). We developed an algorithm to image standard fetal echocardiographic planes by drawing four dissecting lines through the longitudinal view of the ductal arch contained in a STIC volume dataset. Three of the lines are locked to provide simultaneous visualization of targeted planes, and the fourth line (unlocked) 'swings' through the ductal arch image (swing technique), providing an infinite number of cardiac planes in sequence. Each line generates the following plane(s): (a) Line 1: three-vessels and trachea view; (b) Line 2: five-chamber view and long-axis view of the aorta (obtained by rotation of the five-chamber view on the y-axis); (c) Line 3: four-chamber view; and (d) 'swing line': three-vessels and trachea view, five-chamber view and/or long-axis view of the aorta, four-chamber view and stomach. The algorithm was then tested in 50 normal hearts in fetuses at 15.3-40 weeks' gestation and visualization rates for cardiac diagnostic planes were calculated. To determine whether the algorithm could identify planes that departed from the normal images, we tested the algorithm in five cases with proven congenital heart defects. In normal cases, the FAST echo algorithm (three locked lines and rotation of the five-chamber view on the y-axis) was able to generate the intended planes (longitudinal view of the ductal arch, pulmonary artery, three-vessels and trachea view, five-chamber view, long-axis view of the aorta, four-chamber view) individually in 100% of cases (except for the three-vessels and trachea view, which was seen in 98% (49/50)) and simultaneously in 98% (49/50). The swing technique was able to generate the three-vessels and trachea view, five-chamber view and/or long

Physiological pulmonary branch stenosis in newborns: 2D-echocardiographic and Doppler characteristics and 4 months follow up

Directory of Open Access Journals (Sweden)

Amer Yazdanparast

2004-02-01

Full Text Available Transient systolic murmurs in neonates and premature infants due to mild left (LPA and right (RPA pulmonary branch stenosis is recognized but follow up studies are lacking. A total of 32 neonates with murmur and 32 controls were evaluated echocardiographically at baseline and in four months follow up. Diameters of LPA and RPA were smaller in patients with murmur. Colour-coded Doppler showed turbulent flow in LPA and RPA in 93% of patients and flow velocities of both pulmonary branches were significantly higher than in controls. The follow up study at 4 months showed absent (23% or decreased murmur (76%. Echocardiographically, absolute and relative diameters of LPA and RPA increased whereas the ratio of main pulmonary artery/aorta did not change suggesting accelerated growth or dilatation of the pulmonary branches. Thus, transient systolic murmurs in neonates are associated with temporary relative hypoplasia of the pulmonary branches which showed increased growth leading to disappearance of the murmur in most cases within 4 months of life.

Echocardiographic findings in infants with presumed congenital Zika syndrome: Retrospective case series study

Science.gov (United States)

Santos, Cleusa C.; Feitosa, Fabiana G.; Ribeiro, Maria C.; Menge, Paulo; Lira, Izabelle M.

2017-01-01

Objective To report the echocardiographic evaluation of 103 infants with presumed congenital Zika syndrome. Methods An observational retrospective study was performed at Instituto de Medicina Integral Prof. Fernando Figueira (IMIP), Recife, Brazil. 103 infants with presumed congenital Zika syndrome. All infants had microcephaly and head computed tomography findings compatible with congenital Zika syndrome. Zika IgM antibody was detected in cerebrospinal fluid samples of 23 infants. In 80 infants, the test was not performed because it was not available at that time. All infants had negative serology for HIV, syphilis, rubella, cytomegalovirus and toxoplasmosis. A complete transthoracic two-dimensional, M-mode, continuous wave and pulsed wave Doppler and color Doppler echocardiographic (PHILIPS HD11XE or HD15) examination was performed on all infants. Results 14/103 (13.5%) echocardiograms were compatible with congenital heart disease: 5 with an ostium secundum atrial septal defect, 8 had a hemodynamically insignificant small apical muscular ventricular septal defect and one infant with dyspnea had a large membranous ventricular septal defect. The echocardiograms considered normal included 45 infants with a persistent foramen ovale and 16 with a minimum patent ductus arteriosus. Conclusions Preliminarily this study suggests that congenital Zika syndrome may be associated with an increase prevalence of congenital heart disease. However the types of defects noted were septal defects, a proportion of which would not be hemodynamically significant. PMID:28426680

Echocardiographic findings in infants with presumed congenital Zika syndrome: Retrospective case series study.

Directory of Open Access Journals (Sweden)

Danielle Di Cavalcanti

Full Text Available To report the echocardiographic evaluation of 103 infants with presumed congenital Zika syndrome.An observational retrospective study was performed at Instituto de Medicina Integral Prof. Fernando Figueira (IMIP, Recife, Brazil. 103 infants with presumed congenital Zika syndrome. All infants had microcephaly and head computed tomography findings compatible with congenital Zika syndrome. Zika IgM antibody was detected in cerebrospinal fluid samples of 23 infants. In 80 infants, the test was not performed because it was not available at that time. All infants had negative serology for HIV, syphilis, rubella, cytomegalovirus and toxoplasmosis. A complete transthoracic two-dimensional, M-mode, continuous wave and pulsed wave Doppler and color Doppler echocardiographic (PHILIPS HD11XE or HD15 examination was performed on all infants.14/103 (13.5% echocardiograms were compatible with congenital heart disease: 5 with an ostium secundum atrial septal defect, 8 had a hemodynamically insignificant small apical muscular ventricular septal defect and one infant with dyspnea had a large membranous ventricular septal defect. The echocardiograms considered normal included 45 infants with a persistent foramen ovale and 16 with a minimum patent ductus arteriosus.Preliminarily this study suggests that congenital Zika syndrome may be associated with an increase prevalence of congenital heart disease. However the types of defects noted were septal defects, a proportion of which would not be hemodynamically significant.

Three-dimensional thoracic aorta principal strain analysis from routine ECG-gated computerized tomography: feasibility in patients undergoing transcatheter aortic valve replacement.

Science.gov (United States)

Satriano, Alessandro; Guenther, Zachary; White, James A; Merchant, Naeem; Di Martino, Elena S; Al-Qoofi, Faisal; Lydell, Carmen P; Fine, Nowell M

2018-05-02

Functional impairment of the aorta is a recognized complication of aortic and aortic valve disease. Aortic strain measurement provides effective quantification of mechanical aortic function, and 3-dimenional (3D) approaches may be desirable for serial evaluation. Computerized tomographic angiography (CTA) is routinely performed for various clinical indications, and offers the unique potential to study 3D aortic deformation. We sought to investigate the feasibility of performing 3D aortic strain analysis in a candidate population of patients undergoing transcatheter aortic valve replacement (TAVR). Twenty-one patients with severe aortic valve stenosis (AS) referred for TAVR underwent ECG-gated CTA and echocardiography. CTA images were analyzed using a 3D feature-tracking based technique to construct a dynamic aortic mesh model to perform peak principal strain amplitude (PPSA) analysis. Segmental strain values were correlated against clinical, hemodynamic and echocardiographic variables. Reproducibility analysis was performed. The mean patient age was 81±6 years. Mean left ventricular ejection fraction was 52±14%, aortic valve area (AVA) 0.6±0.3 cm 2 and mean AS pressure gradient (MG) 44±11 mmHg. CTA-based 3D PPSA analysis was feasible in all subjects. Mean PPSA values for the global thoracic aorta, ascending aorta, aortic arch and descending aorta segments were 6.5±3.0, 10.2±6.0, 6.1±2.9 and 3.3±1.7%, respectively. 3D PSSA values demonstrated significantly more impairment with measures of worsening AS severity, including AVA and MG for the global thoracic aorta and ascending segment (panalysis is clinically feasible from routine ECG-gated CTA. Appropriate reductions in PSSA were identified with increasing AS hemodynamic severity. Expanded study of 3D aortic PSSA for patients with various forms of aortic disease is warranted.

Three-dimensional surface reconstruction imaging for evaluation of congenital heart disease from ECG-triggered MR images

International Nuclear Information System (INIS)

Vannier, M.W.; Laschinger, J.; Knapp, R.H.; Gutierrez, F.R.; Gronnemeyer, S.A.

1987-01-01

Three-dimensional surface reconstruction images of the heart and great vessels were produced from contiguous sequences of electrocardiographically triggered MR images in 25 patients with congenital heart disease and in three healthy subjects. The imaging data were semiautomatically processed to separate the epicardial and endocardial surfaces and to define the outline of the enclosed blood volumes on a section by section basis. Images were obtained at 5-mm intervals in patients aged 3 months to 30 years with anomalies of the great vessels, tetralogy of Fallot, septal defects, pulmonary atresia, and other congenital heart malformations. The results were used to facilitate the surgical treatment of these patients and were compared with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. These surface reconstruction images were useful for communicating the results of diagnostic examinations to cardiac surgeons, for sizing and location of intracardiac defects, for imaging the pulmonary venous drainage, and for assessing regional and global function

Noninvasive characterization of carotid plaque strain.

Science.gov (United States)

Khan, Amir A; Sikdar, Siddhartha; Hatsukami, Thomas; Cebral, Juan; Jones, Michael; Huston, John; Howard, George; Lal, Brajesh K

2017-06-01

Current risk stratification of internal carotid artery plaques based on diameter-reducing percentage stenosis may be unreliable because ischemic stroke results from plaque disruption with atheroembolization. Biomechanical forces acting on the plaque may render it vulnerable to rupture. The feasibility of ultrasound-based quantification of plaque displacement and strain induced by hemodynamic forces and their relationship to high-risk plaques have not been determined. We studied the feasibility and reliability of carotid plaque strain measurement from clinical B-mode ultrasound images and the relationship of strain to high-risk plaque morphology. We analyzed carotid ultrasound B-mode cine loops obtained in patients with asymptomatic ≥50% stenosis during routine clinical scanning. Optical flow methods were used to quantify plaque motion and shear strain during the cardiac cycle. The magnitude (maximum absolute shear strain rate [MASSR]) and variability (entropy of shear strain rate [ESSR] and variance of shear strain rate [VSSR]) of strain were combined into a composite shear strain index (SSI), which was assessed for interscan repeatability and correlated with plaque echolucency. Nineteen patients (mean age, 70 years) constituting 36 plaques underwent imaging; 37% of patients (n = 7) showed high strain (SSI ≥0.5; MASSR, 2.2; ESSR, 39.7; VSSR, 0.03) in their plaques; the remaining clustered into a low-strain group (SSI routine B-mode imaging using clinical ultrasound machines. High plaque strain correlates with known high-risk echolucent morphology. Strain measurement can complement identification of patients at high risk for plaque disruption and stroke. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Changes in Mitral Annular Ascent with Worsening Echocardiographic Parameters of Left Ventricular Diastolic Function

Directory of Open Access Journals (Sweden)

Paula M. Hernández Burgos

2016-01-01

Full Text Available Background. While the mitral annular plane systolic excursion (MAPSE has been suggested as a surrogate measurement of left ventricular ejection fraction, less is known about the relative value of mitral annular ascent (MAa. Methods. Our database was queried for complete transthoracic echocardiograms performed for any clinical indication. Baseline echocardiographic measurements were compared to determine any correlation between MAa and traditional Echo-Doppler echocardiographic measures to characterize left ventricular diastolic dysfunction (LVDD. Results. Patients with normal LV diastolic function were younger (41±13 years than patients with LVDD (stage 1: 61±13 years; stage 2: 57±14 years; and stage 3: 66±17 years; p=0.156. LV ejection fraction decreased in patients with stage 2 LVDD (63±17% and was further reduced in patients with stage 3 LVDD (28±21; p=0.003. Discussion. While a vigorous MAa excursion was seen in patients with stage 1 LVDD, MAa significantly decreased in stage 2 and stage 3 LVDD patients. Our results highlight the importance of atrioventricular coupling, as MAa motion seems to reflect changes in left atrial pressure. Additional studies are now required to better examine atrioventricular interactions and electromechanical coupling that might improve our assessment of LV diastolic function.

Echocardiographic evaluation of simple versus complex congenital heart disease in a tertiary care Paediatrics Hospital

Directory of Open Access Journals (Sweden)

Uttam Kumar Sarkar

2017-10-01

Full Text Available Background & Objectives:Congenital heart diseases are treatable either by catheter based intervention or open heart surgery according to their quality. In our study we aim to analyze congenital heart disease echocardiographically into simple versus complex heart disease at a tertiary care centre with a public health planning and policy making perspective.Materials & Methods:This hospital based study was done on 1010 patients, both from in-patient and out-patient, who were clinically suspected to have heart disease from January 2015 to September 2016 at Dr.B.C.Roy P.G.I.P.S. Kolkata and echocardiographically categorized.Results:A VSD was the commonest acyanotic heart disease (17. 08%.Tetralogy of Fallot (TOF was commonest complex cyanotic heart disease (10.64%, VSD +ASD was the commonest combined lesion (8.12%. Simple heart lesions (63.1% were commoner than complex (36.9% congenital heart diseases.Conclusion:Health policy makers should give due care to manage Congenital Heart Disease either catheter based or surgically keeping in mind about 63.1% of the lesions are simple cardiac lesions and 36.9% lesions are complex cardiac lesion where complex surgery is required. 

Quantitation of stress echocardiography by tissue Doppler and strain rate imaging: a dream come true?

Science.gov (United States)

Galderisi, Maurizio; Mele, Donato; Marino, Paolo Nicola

2005-01-01

Tissue Doppler (TD) is an ultrasound tool providing a quantitative agreement of left ventricular regional myocardial function in different modalities. Spectral pulsed wave (PW) TD, performed online during the examination, measures instantaneous myocardial velocities. By means of color TD, velocity images are digitally stored for subsequent off-line analysis and mean myocardial velocities are measured. An implementation of color TD includes strain rate imaging (SRI), based on post-processing conversion of regional velocities in local myocardial deformation rate (strain rate) and percent deformation (strain). These three modalities have been applied to stress echocardiography for quantitative evaluation of regional left ventricular function and detection of ischemia and viability. They present advantages and limitations. PWTD does not permit the simultaneous assessment of multiple walls and therefore is not compatible with clinical stress echocardiography while it could be used in a laboratory setting. Color TD provides a spatial map of velocity throughout the myocardium but its results are strongly affected by the frame rate. Both color TD and PWTD are also influenced by overall cardiac motion and tethering from adjacent segments and require reference velocity values for interpretation of regional left ventricular function. High frame rate (i.e. > 150 ms) post-processing-derived SRI can potentially overcome these limitations, since measurements of myocardial deformation have not any significant apex-to-base gradient. Preliminary studies have shown encouraging results about the ability of SRI to detect ischemia and viability, in terms of both strain rate changes and/or evidence of post-systolic thickening. SRI is, however, Doppler-dependent and time-consuming. Further technical refinements are needed to improve its application and introduce new ultrasound modalities to overcome the limitations of the Doppler-derived deformation analysis.

Multiscale segmentation-aided digital image correlation for strain concentration characterization of a turbine blade fir-tree root

Science.gov (United States)

Sun, Chen; Zhou, Yihao; Li, Yang; Chen, Jubing; Miao, Hong

2018-04-01

In this paper, a multiscale segmentation-aided digital image correlation method is proposed to characterize the strain concentration of a turbine blade fir-tree root during its contact with the disk groove. A multiscale approach is implemented to increase the local spatial resolution, as the strain concentration area undergoes highly non-uniform deformation and its size is much smaller than the contact elements. In this approach, a far-field view and several near-field views are selected, aiming to get the full-field deformation and local deformation simultaneously. To avoid the interference of different cameras, only the optical axis of the far-field camera is selected to be perpendicular to the specimen surface while the others are inclined. A homography transformation is optimized by matching the feature points, to rectify the artificial deformation caused by the inclination of the optical axis. The resultant genuine near-field strain is thus obtained after the transformation. A real-world experiment is carried out and the strain concentration is characterized. The strain concentration factor is defined accordingly to provide a quantitative analysis.

Precision of DVC approaches for strain analysis in bone imaged with μCT at different dimensional levels.

Science.gov (United States)

Dall'Ara, Enrico; Peña-Fernández, Marta; Palanca, Marco; Giorgi, Mario; Cristofolini, Luca; Tozzi, Gianluca

2017-11-01

Accurate measurement of local strain in heterogeneous and anisotropic bone tissue is fundamental to understand the pathophysiology of musculoskeletal diseases, to evaluate the effect of interventions from preclinical studies, and to optimize the design and delivery of biomaterials. Digital volume correlation (DVC) can be used to measure the three-dimensional displacement and strain fields from micro-Computed Tomography (µCT) images of loaded specimens. However, this approach is affected by the quality of the input images, by the morphology and density of the tissue under investigation, by the correlation scheme, and by the operational parameters used in the computation. Therefore, for each application the precision of the method should be evaluated. In this paper we present the results collected from datasets analyzed in previous studies as well as new data from a recent experimental campaign for characterizing the relationship between the precision of two different DVC approaches and the spatial resolution of the outputs. Different bone structures scanned with laboratory source µCT or Synchrotron light µCT (SRµCT) were processed in zero-strain tests to evaluate the precision of the DVC methods as a function of the subvolume size that ranged from 8 to 2500 micrometers. The results confirmed that for every microstructure the precision of DVC improves for larger subvolume size, following power laws. However, for the first time large differences in the precision of both local and global DVC approaches have been highlighted when SRµCT or in vivo µCT images were used instead of conventional ex vivo µCT. These findings suggest that in situ mechanical testing protocols applied in SRµCT facilities should be optimized in order to allow DVC analyses of localized strain measurements. Moreover, for in vivo µCT applications DVC analyses should be performed only with relatively course spatial resolution for achieving a reasonable precision of the method. In conclusion

Comparison of contrast in brightness mode and strain ultrasonography of glial brain tumours

International Nuclear Information System (INIS)

Selbekk, Tormod; Brekken, Reidar; Indergaard, Marit; Solheim, Ole; Unsgård, Geirmund

2012-01-01

Image contrast between normal tissue and brain tumours may sometimes appear to be low in intraoperative ultrasound. Ultrasound imaging of strain is an image modality that has been recently explored for intraoperative imaging of the brain. This study aims to investigate differences in image contrast between ultrasound brightness mode (B-mode) images and ultrasound strain magnitude images of brain tumours. Ultrasound radiofrequency (RF) data was acquired during surgery in 15 patients with glial tumours. The data were subsequently processed to provide strain magnitude images. The contrast in the B-mode images and the strain images was determined in assumed normal brain tissue and tumour tissue at selected regions of interest (ROI). Three measurements of contrast were done in the ultrasound data for each patient. The B-mode and strain contrasts measurements were compared using the paired samples t- test. The statistical analysis of a total of 45 measurements shows that the contrasts in the strain magnitude images are significantly higher than in the conventional ultrasound B-mode images (P < 0.0001). The results indicate that ultrasound strain imaging provides better discrimination between normal brain tissue and glial tumour tissue than conventional ultrasound B-mode imaging. Ultrasound imaging of tissue strain therefore holds the potential of becoming a valuable adjunct to conventional intraoperative ultrasound imaging in brain tumour surgery

Trypanosoma cruzi in dogs: electrocardiographic and echocardiographic evaluation, in Malinalco, State of Mexico

Directory of Open Access Journals (Sweden)

González-Vieyra SD

2011-12-01

Full Text Available Sandra Díaz González-Vieyra1, Ninfa Ramírez-Durán2, Ángel H Sandoval-Trujillo3, Juan C Vázquez-Chagoyán1, Humberto G Monroy-Salazar1, Alberto Barbabosa-Pliego11Research Center of Advanced Studies in Animal Health, Veterinary Husbandry School, 2Medical and Ambiental Microbiology, Research Center of Advanced Studies in Health Science, School of Medicine, Autonomous University of the State of Mexico, Toluca, Mexico; 3Department of Biological Systems, Metropolitan Autonomous University, Xochimilco, Mexico City, MexicoAbstract: Chagas disease caused by Trypanosoma cruzi is an important public health problem in Latin America. Dogs are considered a risk factor for human Chagas disease, a sentinel for T. cruzi infection in endemic regions and an animal model to study pathological aspects of the disease. The potential use of dogs as indicators of human cardiac pathogenicity of local T. cruzi strains has been studied insufficiently. We studied electrocardiographic (EKG and echocardiographic (ECG alteration frequencies observed in an open population of dogs in Malinalco, Mexico, and determined if such frequencies were statistically associated with T. cruzi infection in dogs. Animals (n = 139 were clinically examined and owners were asked to answer a questionnaire about dogs’ living conditions. Two commercial serological tests (IHA, ELISA were conducted to detect anti-T. cruzi serum antibodies. Significant differences between seropositive and seronegative animals in cardiomyopathic frequencies were detected through EKG and ECG (P < 0.05. Thirty dogs (21.58% were serologically positive to anti-T. cruzi antibodies (to ELISA and IHA assays, of which nine (30% had EKG and/or ECG alterations. From the remaining 104 (78.42% seronegative animals, five (4.5% had EKG and/or ECG abnormalities. Our data support the hypothesis that most EKG and ECG alterations found in dogs from Malinalco could be associated with T. cruzi infection. Considering the dog as a

Echocardiographic evaluation of patients with subacute sclerosing panencephalitis

Directory of Open Access Journals (Sweden)

Derya Çimen

2014-03-01

Full Text Available Objective: Subacute sclerosing panencephalitis is a slowly progressive, inflammatory and neurodegenerative disease caused by virus infection in the central nervous system. Since there are a limited number of studies in the literature evaluating the cardiovascular functions of patients with SSPE, the present study evaluates the patients with SSPE using tissue Doppler echocardiography and compares them between the control group in order to shed some light on the subject. Methods: The study is a prospective observational study. 49 patients (17 female, 32 male with SSPE were included in the study. Patients were divided into two groups: Stage 2 (n=29 and Stage 3 (n=20. Echocardiographic data were compared with a control group of 26 which is the same average age. All children underwent a detailed echocardiography, which contained an M-mode, pulse Doppler and tissue Doppler imaging. Results: Sinus tachycardia ( >100 beats/min in children was detected in nineteen (38.7% patients. There were not significant differences between parameters of systolic and diastolic function of the heart. Stage 2 group, EF: 69.9±6.4; SF: 39.2±5.58; and MPI (mitral: 0.38±0.03 and MPI (tricuspid: 0.39±0.10. And in the Stage 3 group, EF: 68.5±7.0, SF: 37.8±5.34, MPI (mitral: 0.37±0.09 and MPI (tricuspid: 0.38±0.12. In the control group EF:70.96±5.54; SF:39.96±5.05 and MPI(mitral: 0.35±0.06 MPI (tricuspid:0.36±0.04 and statistically meaningful differences were not found between patients and control groups (p >0.05. Conclusion: Cardiac functions may be preserved and cardiac functions constitute no significant risks of mortality in the advanced stages of patients with Subacute sclerosing panencephalitis, which is a group of chronic and bedridden patients.

Effect of advanced chronic kidney disease in clinical and echocardiographic outcomes of patients treated with MitraClip system

DEFF Research Database (Denmark)

Estévez-Loureiro, Rodrigo; Settergren, Magnus; Pighi, Michele

2015-01-01

BACKGROUND: Data regarding the influence of different levels of renal dysfunction on clinical and echocardiographic results of MitraClip therapy are scarce. We aimed to evaluate the impact of baseline advance renal failure in the outcomes of a cohort of patients treated with MitraClip. METHODS AN...

Structure and function of the tricuspid and bicuspid regurgitant aortic valve: an echocardiographic study.

Science.gov (United States)

Rönnerfalk, Mattias; Tamás, Éva

2015-07-01

The emerging new treatment options for aortic valve disease call for more sophisticated diagnostics. We aimed to describe the echocardiographic pathophysiology and characteristics of the purely regurgitant aortic valve in detail. Twenty-nine men, with chronic aortic regurgitation without concomitant heart disease referred for aortic valve intervention, underwent 2D transoesophageal echocardiographic (TEE) examination prior to surgery according to a previously published matrix. Measurements of the aortic valve apparatus in long and short axis view were made in systole and diastole and analysed off-line. The aortic valves were grouped as tricuspid (TAV) or bicuspid (BAV), and classified by regurgitation mechanism. Twenty-four examinations were eligible for analysis of which 13 presented TAV and 11 BAV. The regurgitation mechanism was classified as dilatation of the aorta in 6 cases, as prolapse in 11 cases and as poor cusp tissue quality or quantity in 7 cases. The ventriculo-aortic junction (VAJ) and valve opening were closely related (TAV r = 0.5, BAV r = 0.73) but no correlation was found between the VAJ and the maximal sinus diameter (maxSiD) or the sinotubular junction (STJ). However, the STJ and maxSiD were significantly related (TAV vs BAV: systole r = 0.9, r = 0.8; diastole r = 0.9, r = 0.7), forming an entity. The conjoined BAV cusps were shorter than the anterior cusps when closed (P = 0.002); the inter-commissural distances of the cusps in the BAV group were significantly different (P = 0.001 resp. 0.03) in both systole and diastole. The VAJ was independent of other aortic dimensions and should thereby be considered as a separate entity with influence on valve opening. The detailed 2D TEE measurements of this study add further important information to our knowledge about the function and echocardiographic anatomy of the pathological aortic valve and root either as a stand-alone examination or as a benchmark and complement to 3D echocardiography. This may

The predictive value of transthoracic echocardiographic variables for sinus rhythm maintenance after electrical cardioversion of atrial fibrillation. Results from the CAPRAF study, a prospective, randomized, placebo-controlled study.

Science.gov (United States)

Grundvold, Irene; Tveit, Arnljot; Smith, Pål; Seljeflot, Ingebjørg; Abdelnoor, Michael; Arnesen, Harald

2008-01-01

The recurrence rate of atrial fibrillation after electrical cardioversion is disappointingly high. The aim of the present study was to prospectively investigate if standard echocardiographic variables at the day of cardioversion could predict sinus rhythm maintenance. Transthoracic echocardiographic examination was performed within 4 h after cardioversion for all the patients in the CAPRAF (Candesartan in the Prevention of Relapsing Atrial Fibrillation) study. Cardioversion was successful for 137 patients not given specific antiarrhythmic therapy, and only 41 (30%) maintained sinus rhythm at 6-month follow-up. There were significant (p = 0.05) lower transmitral A wave velocities in the group with relapsing atrial fibrillation compared with the group with sinus rhythm at 6-month follow-up. All patients with the lowest A wave velocities had an early recurrence of atrial fibrillation. There were no differences between the groups regarding atrial dimensions or left ventricular function. The use of the angiotensin II receptor antagonist candesartan had no influence on the echocardiographic variables, nor on the recurrence rate of atrial fibrillation after cardioversion. Transthoracic echocardiographic examination performed a short time after electrical cardioversion of atrial fibrillation showed that only A wave peak velocities were significantly predictive of sinus rhythm maintenance 6 months after the procedure. (c) 2008 S. Karger AG, Basel.

SQL based cardiovascular ultrasound image classification.

Science.gov (United States)

Nandagopalan, S; Suryanarayana, Adiga B; Sudarshan, T S B; Chandrashekar, Dhanalakshmi; Manjunath, C N

2013-01-01

This paper proposes a novel method to analyze and classify the cardiovascular ultrasound echocardiographic images using Naïve-Bayesian model via database OLAP-SQL. Efficient data mining algorithms based on tightly-coupled model is used to extract features. Three algorithms are proposed for classification namely Naïve-Bayesian Classifier for Discrete variables (NBCD) with SQL, NBCD with OLAP-SQL, and Naïve-Bayesian Classifier for Continuous variables (NBCC) using OLAP-SQL. The proposed model is trained with 207 patient images containing normal and abnormal categories. Out of the three proposed algorithms, a high classification accuracy of 96.59% was achieved from NBCC which is better than the earlier methods.

Detection of Early Right Ventricular Dysfunction in Young Patients With Thalassemia Major Using Tissue Doppler Imaging

Science.gov (United States)

Bornaun, Helen; Dedeoglu, Reyhan; Oztarhan, Kazim; Dedeoglu, Savas; Erfidan, Erkan; Gundogdu, Muge; Aydogan, Gonul; Cengiz, Dicle

2016-01-01

Background Myocardial iron overload is the most common cause of mortality in patients with thalassemia major (TM), also known as beta-thalassemia. T2* cardiovascular magnetic resonance imaging (MRI) is the best way of monitoring cardiac iron, and new echocardiographic techniques can be used to assess cardiac function. Objectives The aim of this study was to assess the systolic and diastolic right ventricular (RV) function of patients with TM using tissue Doppler imaging (TDI) and to determine whether this echocardiographic technique is an adequate diagnostic tool for the screening and detection of subclinical cardiac dysfunction. Patients and Methods Eighty-four patients with TM were evaluated by conventional echocardiography and pulse-wave TDI. The data of the TM group (Group 1) were compared with that of 85 age- and sex-matched healthy controls (Group 2). Cardiovascular T2* MRI examinations were performed in 49 of the 85 patients. Results The patients with TM had significantly lower values for weight, height, body mass index, systolic arterial pressure, deceleration time, E’/A’, and ejection time (ET) than the controls. Group 1 also had significantly higher values for peak early diastolic velocity (E) over peak late diastolic velocity (A), peak early diastolic velocity of TDI (E’), peak late diastolic velocity of TDI (A’), E/E’, isovolumetric relaxation time, isovolumetric contraction time, and RV magnetic perfusion imaging (MPI) than Group 2. Conclusions RV diastolic dysfunction occurs before systolic deterioration in patients with TM and cannot be screened with conventional echocardiographic techniques. In routine practice, TDI measurements, MPI (for global function) and the E/E’ parameter (for diastolic function) can be used to screen and detect early RV dysfunction. PMID:27617076

Focused review on transthoracic echocardiographic assessment of patients with continuous axial left ventricular assist devices.

Science.gov (United States)

Topilsky, Yan; Maltais, Simon; Oh, Jae K; Atchison, Fawn W; Perrault, Louis P; Carrier, Michel; Park, Soon J

2011-02-08

Left ventricular assist devices (LVADs) are systems for mechanical support for patients with end-stage heart failure. Preoperative, postoperative and comprehensive followup with transthoracic echocardiography has a major role in LVAD patient management. In this paper, we will present briefly the hemodynamics of axial-flow LVAD, the rationale, and available data for a complete and organized echocardiographic assessment in these patients including preoperative assessment, postoperative and long-term evaluation.

Mechanical dispersion and global longitudinal strain by speckle tracking echocardiography: Predictors of appropriate implantable cardioverter defibrillator therapy in hypertrophic cardiomyopathy.

Science.gov (United States)

Candan, Ozkan; Gecmen, Cetin; Bayam, Emrah; Guner, Ahmet; Celik, Mehmet; Doğan, Cem

2017-06-01

In this study, we investigated whether mechanical dispersion which reflects electrical abnormality and other echocardiographic and clinic parameters predict appropriate ICD shock in patients undergone ICD implantation for hypertrophic cardiomyopathy. Sixty-three patients who received ICD implantation for primary or secondary prevention were included in the study. Patients' clinical, electrocardiographic, 2D classic, and speckle tracking echocardiographic data were collected. Mechanical dispersion was defined as the standard deviation of time to peak negative strain in 18 left ventricular segments. Appropriate ICD therapy was defined as cardioversion or defibrillation due to ventricular tachycardia or fibrillation. Patients were divided into two groups as occurrence or the absence of appropriate ICD therapy. A total of 17 (26.9%) patients were observed to have an appropriate ICD therapy during follow-up periods. In patients who performed appropriate ICD therapy, a larger left atrial volume index, higher sudden cardiac death (SCD)-Risk Score, longer mechanical dispersion, and decreased global longitudinal peak strain (GLPS) were observed. In multivariate logistic regression analysis, including (GLPS, mechanical dispersion, LAVi, and SCD-Risk Score) was used to determine independent predictors of occurrence of appropriate ICD therapy during the follow-up. Mechanical dispersion, GLPS, and SCD-Risk Score were found to be independent predictors of occurrence of appropriate ICD therapy. Mechanical dispersion, GLPS, and SCD-Risk Score were found to be predictive for appropriate ICD therapy in patients receiving ICD implantation. Readily measurable mechanical dispersion and GLPS could be helpful to distinguish patients at high risk who could optimally benefit from ICD therapy. © 2017, Wiley Periodicals, Inc.

Strain-Encoded Cardiac Magnetic Resonance Imaging as an Adjunct for Dobutamine Stress Testing. Incremental Value to Conventional Wall Motion Analysis

Science.gov (United States)

Korosoglou, Grigorios; Lossnitzer, Dirk; Schellberg, Dieter; Lewien, Antje; Wochele, Angela; Schaeufele, Tim; Neizel, Mirja; Steen, Henning; Giannitsis, Evangelos; Katus, Hugo A.; Osman, Nael F.

2009-01-01

Background High-dose dobutamine stress magnetic resonance imaging (DS-MRI) is safe and feasible for the diagnosis of coronary artery disease (CAD) in humans. However, the assessment of cine scans relies on the visual interpretation of regional wall motion, which is subjective. Recently, Strain-Encoded MRI (SENC) has been proposed for the direct color-coded visualization of myocardial strain. The purpose of our study was to compare the diagnostic value of SENC to that provided by conventional wall motion analysis for the detection of inducible ischemia during DS-MRI. Methods and Results Stress induced ischemia was assessed by wall motion analysis and by SENC in 101 patients with suspected or known CAD and in 17 healthy volunteers who underwent DS-MRI in a clinical 1.5T scanner. Quantitative coronary angiography deemed as the standard reference for the presence or absence of significant CAD (≥50% diameter stenosis). On a coronary vessel level, SENC detected inducible ischemia in 86/101 versus 71/101 diseased coronary vessels (p<0.01 versus cine), and showed normal strain response in 189/202 versus 194/202 vessels with <50% stenosis (p=NS versus cine). On a patient level, SENC detected inducible ischemia in 63/64 versus 55/64 patients with CAD (p<0.05 versus cine), and showed normal strain response in 32/37 versus 34/37 patients without CAD (p=NS versus cine).Quantification analysis demonstrated a significant correlation between strain rate reserve (SRreserve) and coronary artery stenosis severity (r²=0.56, p<0.001), and a cut-off value of SRreserve=1.64 deemed as a highly accurate marker for the detection of stenosis≥50% (AUC=0.96, SE=0.01, 95% CI = 0.94–0.98, p<0.001). Conclusions The direct color-coded visualization of strain on MR-images is a useful adjunct for DS-MRI, which provides incremental value for the detection of CAD compared to conventional wall motion readings on cine images. PMID:19808579

Echocardiographic estimation of right ventricular stroke work in children with pulmonary arterial hypertension: comparison with invasive measurements.

Science.gov (United States)

Di Maria, Michael V; Burkett, Dale A; Younoszai, Adel K; Landeck, Bruce F; Mertens, Luc; Ivy, D Dunbar; Friedberg, Mark K; Hunter, Kendall S

2015-11-01

Right ventricular (RV) failure is a key determinant of mortality in children with pulmonary arterial hypertension (PAH). RV stroke work (RVSW) can be estimated as the product of RV systolic pressure and stroke volume. The authors have shown that RVSW predicts adverse outcomes in this population when derived from hemodynamic data; noninvasive assessment of RVSW may be advantageous but has not been assessed. There are few data validating noninvasive versus invasive measurements in children with PAH. The aim of this study was to compare echocardiographically derived RVSW with RVSW determined from hemodynamic data. This was a retrospective study, including subjects with idiopathic PAH and minor or repaired congenital heart disease. Forty-nine subjects were included, in whom cardiac catheterization and echocardiography were performed within 1 month. Fourteen additional patients were included in a separate cohort, in whom catheterization and echocardiography were performed simultaneously. Catheterization-derived RVSW was calculated as RV systolic pressure × (cardiac output/heart rate). Echocardiographically derived RVSW was calculated as 4 × (peak tricuspid regurgitant jet velocity)(2) × (pulmonary valve area × velocity-time integral). Statistics included the intraclass correlation coefficient and Bland-Altman analysis. Echocardiographically derived RVSW was linearly correlated with invasively derived RVSW (r = 0.74, P work was related to indexed pulmonary vascular resistance (r = 0.43, P = .002), tricuspid annular plane systolic excursion (r = 0.41, P = .004), and RV wall thickness (r = 0.62, P work, a potential novel index of RV function, can be estimated noninvasively and is related to pulmonary hemodynamics and other indices of RV performance. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

The relationship between BNP, NTproBNP and echocardiographic measurements of systemic blood flow in very preterm infants.

Science.gov (United States)

König, K; Guy, K J; Walsh, G; Drew, S M; Watkins, A; Barfield, C P

2014-04-01

Preterm infants are at risk of circulatory compromise following birth. Functional neonatal echocardiography including superior vena cava (SVC) flow is increasingly used in neonatal medicine, and low SVC flow has been associated with adverse outcome. However, echocardiography is not readily available in many neonatal units and B-type natriuretic peptides (BNPs) may be useful in guiding further cardiovascular assessment. This study investigated the relationship between BNP, N-terminal pro-BNP (NTproBNP) and echocardiographic measurements of systemic blood flow in very preterm infants. This is a prospective observational study. Sixty preterm infants flow, left and right ventricular output (LVO and RVO). Statistical analysis included simple linear regression of BNP and NTproBNP with echocardiographic measures and multiple regression including potential confounding variables. Mean (s.d.) gestational age at birth was 27(5) (2(1)) weeks, median (interquartile range, IQR) birth weight was 995 (845 to 1175) grams. Neither BNP nor NTproBNP correlated with SVC flow (BNP 95% confidence interval (CI) -0.0014 to 0.013, P=0.12; NTproBNP 95% CI -0.00069 to 0.01, P=0.085); LVO (BNP 95% CI -0.00078 to 0.0072, P=0.11; NTproBNP 95% CI -0.0034 to 0.0034, P=0.99); RVO (BNP 95% CI -0.00066 to 0.0058, P=0.12; NTproBNP 95% CI -0.0012 to 0.0044, P=0.25); or FS (BNP 95% CI -0.053 to 0.051, P=0.96; NTproBNP 95% CI -0.061 to 0.019, P=0.3). Multivariate linear regression did not significantly alter results. In this cohort of very preterm infants, BNP and NTproBNP did not correlate with echocardiographic measurements of systemic blood flow within the first 72 h of life.

Echocardiographic Risk Factors for Stroke and Outcomes in Patients With Atrial Fibrillation Anticoagulated With Apixaban or Warfarin.

Science.gov (United States)

Vinereanu, Dragos; Lopes, Renato D; Mulder, Hillary; Gersh, Bernard J; Hanna, Michael; de Barros E Silva, Pedro G M; Atar, Dan; Wallentin, Lars; Granger, Christopher B; Alexander, John H

2017-12-01

Few data exist on the long-term outcomes of patients with spontaneous echo contrast (SEC), left atrial/left atrial appendage (LA/LAA) thrombus, and complex aortic plaque (CAP), in patients with atrial fibrillation receiving oral anticoagulation. We explored the relationship between these 3 echocardiographic findings and clinical outcomes, and the comparative efficacy and safety of apixaban and warfarin for each finding. Patients from the ARISTOTLE trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) with SEC, LA/LAA thrombus, or CAP diagnosed by either transthoracic or transesophageal echocardiography were compared with patients with none of these findings on transesophageal echocardiography. A total of 1251 patients were included: 217 had SEC, 127 had LA/LAA thrombus, 241 had CAP, and 746 had none. The rates of stroke/systemic embolism were not significantly different among patients with and without these echocardiographic findings (hazard ratio, 0.96; 95% confidence interval, 0.25-3.60 for SEC; hazard ratio, 1.27; 95% confidence interval, 0.23-6.86 for LA/LAA thrombus; hazard ratio, 2.21; 95% confidence interval, 0.71-6.85 for CAP). Rates of ischemic stroke, myocardial infarction, cardiovascular death, and all-cause death were also not different between patients with and without these findings. For patients with either SEC or CAP, there was no evidence of a differential effect of apixaban over warfarin. For patients with LA/LAA thrombus, there was also no significant interaction, with the exception of all-cause death and any bleeding where there was a greater benefit of apixaban compared with warfarin among patients with no LA/LAA thrombus. In anticoagulated patients with atrial fibrillation and risk factors for stroke, echocardiographic findings do not seem to add to the risk of thromboembolic events. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984. © 2017 American Heart Association, Inc.

Correlation between the tissue Doppler, strain rate, strain imaging during the dobutamine infusion and coronary fractional flow reserve during catheterization: a comparative study.

Science.gov (United States)

Dagdelen, Sinan; Yuce, Murat; Emiroglu, Yunus; Ergelen, Mehmet; Pala, Selcuk; Tanalp, Ali Cevat; Izgi, Akin; Kirma, Cevat

2005-06-22

Coronary fractional flow reserve (FFR) as an invasive, and dobutamine stress echocardiography (DSE) as a noninvasive technique were used to detect critical coronary stenosis. This study was undertaken to assess correlation between these two techniques by using tissue Doppler, strain rate (SR), and strain imaging (S). In 17 patients (aged 54.9+/-12.6, 4 F), a total of 22 vessels were studied. On dobutamine stress echocardiography, baseline and peak systolic (Sm), early (Em) and late (Am) diastolic myocardial velocities, SR and S were recorded from parasternal view (mid-posterior segment) for radial and apical view (mid-septum) for longitudinal deformation. Then coronary FFR was performed by using intracoronary adenosine infusion, and the value of system were analyzed for longitudinal SR and S values, it had a mild correlation with SR (r = 0.47, p = 0.044) and a good correlation with S (r = 0.66, p = 0.002). The quantification of regional myocardial deformation by using DSE rather than the motion would be more appropriate in detecting the ischemic dysfunctional segment supplied by the critical coronary stenosis. Strain measurement during the dobutamine infusion may provide an information on the FFR results of the culprit vessel.

Detecting hepatic steatosis using ultrasound-induced thermal strain imaging: an ex vivo animal study

International Nuclear Information System (INIS)

Mahmoud, Ahmed M; Ding, Xuan; Dutta, Debaditya; Kim, Kang; Singh, Vijay P

2014-01-01

Hepatic steatosis or fatty liver disease occurs when lipids accumulate within the liver and can lead to steatohepatitis, cirrhosis, liver cancer and eventual liver failure requiring liver transplant. Conventional brightness mode (B-mode) ultrasound (US) is the most common noninvasive diagnostic imaging modality used to diagnose hepatic steatosis in clinics. However, it is mostly subjective or requires a reference organ such as the kidney or spleen with which to compare. This comparison can be problematic when the reference organ is diseased or absent. The current work presents an alternative approach to noninvasively detecting liver fat content using US-induced thermal strain imaging (US-TSI). This technique is based on the difference in the change in the speed of sound as a function of temperature between water- and lipid-based tissues. US-TSI was conducted using two system configurations including a mid-frequency scanner with a single linear array transducer (5–14 MHz) for both imaging and heating and a high-frequency (13–24 MHz) small animal imaging system combined with a separate custom-designed US heating transducer array. Fatty livers (n = 10) with high fat content (45.6 ± 11.7%) from an obese mouse model and control livers (n = 10) with low fat content (4.8 ± 2.9%) from wild-type mice were embedded in gelatin. Then, US imaging was performed before and after US induced heating. Heating time periods of ∼3 s and ∼9.2 s were used for the mid-frequency imaging and high-frequency imaging systems, respectively, to induce temperature changes of approximately 1.5 °C. The apparent echo shifts that were induced as a result of sound speed change were estimated using 2D phase-sensitive speckle tracking. Following US-TSI, histology was performed to stain lipids and measure percentage fat in the mouse livers. Thermal strain measurements in fatty livers (−0.065 ± 0.079%) were significantly (p < 0.05) higher than those measured in control livers (−0.124�

Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction.

Directory of Open Access Journals (Sweden)

Tor Biering-Sørensen

Full Text Available Global longitudinal systolic strain (GLS has recently been demonstrated to be a superior prognosticator to conventional echocardiographic measures in patients after myocardial infarction (MI. The aim of this study was to evaluate the prognostic value of regional longitudinal myocardial deformation in comparison to GLS, conventional echocardiography and clinical information.In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI, treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All patients were examined by tissue Doppler imaging (TDI and two-dimensional strain echocardiography (2DSE.During a median-follow-up of 5.3 (IQR 2.5-6.1 years the primary endpoint (death, heart failure or a new MI was reached by 145 (38.9% patients. After adjustment for significant confounders (including conventional echocardiographic parameters and culprit lesion, reduced longitudinal performance in the anterior septal and inferior myocardial regions (but not GLS remained independent predictors of the combined outcome. Furthermore, inferior myocardial longitudinal deformation provided incremental prognostic information to clinical and conventional echocardiographic information (Harrell's c-statistics: 0.63 vs. 0.67, p = 0.032. In addition, impaired longitudinal deformation outside the culprit lesion perfusion region was significantly associated with an adverse outcome (p<0.05 for all deformation parameters.Regional longitudinal myocardial deformation measures, regardless if determined by TDI or 2DSE, are superior prognosticators to GLS. In addition, impaired longitudinal deformation in the inferior myocardial segment provides prognostic information over and above clinical and conventional echocardiographic risk factors. Furthermore, impaired longitudinal deformation outside the culprit lesion perfusion region seems to be a paramount marker of adverse outcome.

Echocardiographic assessment with right ventricular function improvement following ultrasound-accelerated catheter-directed thrombolytic therapy in submassive pulmonary embolism.

Science.gov (United States)

Doheny, Charles; Gonzalez, Lorena; Duchman, Stanley M; Varon, Joseph; Bechara, Carlos F; Cheung, Mathew; Lin, Peter H

2018-06-01

Introduction The objective of this study was to evaluate the efficacy of ultrasound-accelerated catheter-directed thrombolytic therapy in patients with submassive pulmonary embolism. Methods Clinical records of 46 patients with submassive pulmonary embolism who underwent ultrasound-accelerated catheter-directed pulmonary thrombolysis using tissue plasminogen activator, from 2007 to 2017, were analyzed. All patients experienced clinical symptoms with computed tomography evidence of pulmonary thrombus burden. Right ventricular dysfunction was present in all patients by echocardiographic finding of right ventricle-to-left ventricle ratio > 0.9. Treatment outcome, procedural complications, right ventricular pressures, and thrombus clearance were evaluated. Follow-up evaluation included echocardiographic assessment of right ventricle-to-left ventricle ratio at one month, six months, and one year. Results Technical success was achieved in all patients ( n = 46, 100%). Our patients received an average of 18.4 ± 4.7 mg of tissue plasminogen activator using ultrasound-accelerated thrombolytic catheter with an average infusion time of 16.5± 5.4 h. Clinical success was achieved in all patients (100%). Significant reduction of mean pulmonary artery pressure occurred following the treatment, which decreased from 36 ± 8 to 21 ± 5 mmHg ( p right ventricular dysfunction based on echocardiographic assessment. The right ventricle-to-left ventricle ratio decreased from 1.32 ± 0.18 to 0.91 ± 0.13 at the time of hospital discharge ( p right ventricular function remained improved at 6 months and 12 months of follow-up, as right ventricle-to-left ventricle ratio were 0.92 ± 0.14 ( p right ventricular function in patients with submassive pulmonary embolism.

Strain histograms are equal to strain ratios in predicting malignancy in breast tumours

DEFF Research Database (Denmark)

Carlsen, Jonathan Frederik; Ewertsen, Caroline; Sletting, Susanne

2017-01-01

Objectives: To assess whether strain histograms are equal to strain ratios in predicting breast tumour malignancy and to see if either could be used to upgrade Breast Imaging Reporting and Data System (BI-RADS) 3 tumours for immediate biopsy. Methods: Ninety-nine breast tumours were examined using...

Hypercholesterolemia and Myocardial function evaluated via Tissue Doppler Imaging

Directory of Open Access Journals (Sweden)

Kotaru Pavan

2009-11-01

Full Text Available Abstract Objective To establish a link between hypercholesterolemia and myocardial dysfunction. Background Heart failure is a complex disease involving changes in systolic and diastolic function. Newer echocardiographic imaging modalities may be able to detect discreet changes in myocardial function associated with hypercholesterolemia. Therefore we sought to establish a link between hypercholesterolemia and myocardial dysfunction with tissue Doppler imaging (TDI. Methods Twenty-seven rabbits were studied: 7 were fed normal chow (group 1 and 20 a high cholesterol diet (10 with ezetimibe, 1 mg/kg/day; group 2 and 10 without, group 3. Echocardiographic images were obtained under general anesthesia. Serum cholesterol levels were obtained at baseline, 3 and 6 months and myocardial cholesterol levels measured following euthanasia. Results Doppler measurements, including E/A, E'/A' and S' were significantly lower in group 3 compared to both groups 1 and 2 but no significant differences were noted in chamber sizes or ejection fraction among the groups. Average serum cholesterol was higher in group 3 compared to groups 1 and 2 respectively (495 ± 305 mg/dl vs. 114 ± 95 mg/dl and 87 ± 37 mg/dl; p 2 = 0.17 p = 0.04, r2 = 0.37 p = 0.001 and r2 = 0.24 p = 0.01. Conclusion Cholesterol load in the serum and myocardium was significantly associated with decreased systolic and diastolic function by TDI. Moreover, lipid lowering was protective.

Characterization of high-strain rate mechanical behavior of AZ31 magnesium alloy using 3D digital image correlation

Energy Technology Data Exchange (ETDEWEB)

Wang, Yanli; Xu, Hanbing; Erdman, Donald L.; Starbuck, Michael J.; Simunovic, Srdjan [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2011-10-15

Characterization of the material mechanical behavior at sub-Hopkinson regime (0.1 to 1 000 s{sup -1}) is very challenging due to instrumentation limitations and the complexity of data analysis involved in dynamic loading. In this study, AZ31 magnesium alloy sheet specimens are tested using a custom designed servo-hydraulic machine in tension at nominal strain rates up to 1 000 s{sup -1}. In order to resolve strain measurement artifacts, the specimen displacement is measured using 3D Digital Image correlation instead from actuator motion. The total strain is measured up to {approx} 30%, which is far beyond the measurable range of electric resistance strain gages. Stresses are calculated based on the elastic strains in the tab of a standard dog-bone shaped specimen. Using this technique, the stresses measured for strain rates of 100 s{sup -1} and lower show little or no noise comparing to load cell signals. When the strain rates are higher than 250 s{sup -1}, the noises and oscillations in the stress measurements are significantly decreased from {approx} 250 to 50 MPa. Overall, it is found that there are no significant differences in the elongation, although the material exhibits slight work hardening when the strain rate is increased from 1 to 100 s{sup -1}. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Three-dimensional MR imaging of congenital heart disease

International Nuclear Information System (INIS)

Laschinger, J.C.; Vannier, M.W.; Knapp, R.H.; Gutierrez, F.R.; Cox, J.L.

1987-01-01

Contiguous 5-mm thick ECG-gated MR images of the thorax were edited using surface reconstruction techniques to produce three-dimensional (3D) images of the heart and great vessels in four healthy individuals and 25 patients with congenital heart disease (aged 3 months-30 years). Anomalies studied include atrial and ventricular septal defects, aortic coarctation, AV canal defects, double outlet ventricles, hypoplastic left heart syndrome, and a wide spectrum of patients with tetralogy of Fallot. The results were correlated with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. Three-dimensional reconstructions accurately localized the dimensions and locations of all cardiac and great vessel anomalies and often displayed anatomic findings not diagnosed or visualized with other forms of diagnostic imaging

A Review of Surface Deformation and Strain Measurement Using Two-Dimensional Digital Image Correlation

Directory of Open Access Journals (Sweden)

Khoo Sze-Wei

2016-09-01

Full Text Available Among the full-field optical measurement methods, the Digital Image Correlation (DIC is one of the techniques which has been given particular attention. Technically, the DIC technique refers to a non-contact strain measurement method that mathematically compares the grey intensity changes of the images captured at two different states: before and after deformation. The measurement can be performed by numerically calculating the displacement of speckles which are deposited on the top of object’s surface. In this paper, the Two-Dimensional Digital Image Correlation (2D-DIC is presented and its fundamental concepts are discussed. Next, the development of the 2D-DIC algorithms in the past 33 years is reviewed systematically. The improvement of 2DDIC algorithms is presented with respect to two distinct aspects: their computation efficiency and measurement accuracy. Furthermore, analysis of the 2D-DIC accuracy is included, followed by a review of the DIC applications for two-dimensional measurements.

Effects of antithrombotic drugs in patients with left ventricular thrombi: assessment with indium-111 platelet imaging and two-dimensional echocardiography

International Nuclear Information System (INIS)

Stratton, J.R.; Ritchie, J.L.

1984-01-01

Patients with left ventricular thrombi not caused by recent myocardial infarction were prospectively studied by indium-111 platelet imaging and two-dimensional echocardiography to determine the reproducibility of these techniques and the short-term effects of sulfinpyrazone (200 mg four times daily), aspirin (325 mg three times daily) plus dipyridamole (75 mg three times daily), and full-dose warfarin. At baseline, all patients underwent indium-111 platelet imaging and echocardiography, and the results were positive for thrombus. In six patients on no antithrombotic drug therapy, repeat platelet scans and echocardiographic studies at 6.0 +/- 3.3 weeks remained positive and were unchanged. In seven patients studied on sulfinpyrazone, three platelet scans became negative, two became equivocal, and two were unchanged; the presence and size of thrombus was constant by echocardiography in all seven patients. Of the six patients studied on aspirin plus dipyridamole, one platelet scan became negative, those of three became equivocal, and two were unchanged; all echocardiographic findings remained positive, but one patient had decreased thrombus size. Among four warfarin-treated patients, three had resolution of platelet deposition and one was unchanged; by echocardiography, thrombus resolved in one patient, was decreased in size in one, and was unchanged in two. We conclude that, in the absence of antithrombotic drug therapy, platelet imaging and echocardiographic findings are stable in patients with left ventricular thrombi not caused by recent myocardial infarction. Sulfinpyrazone, aspirin plus dipyridamole, and warfarin all interrupt platelet deposition in some patients with chronic left ventricular thrombi

Echocardiographic left ventricular masses in distance runners and weight lifters

Science.gov (United States)

Longhurst, J. C.; Gonyea, W. J.; Mitchell, J. H.; Kelly, A. R.

1980-01-01

The relationships of different forms of exercise training to left ventricular mass and body mass are investigated by echocardiographic studies of weight lifters, long-distance runners, and comparatively sized untrained control subjects. Left ventricular mass determinations by the Penn convention reveal increased absolute left ventricular masses in long-distance runners and competitive weight lifters with respect to controls matched for age, body weight, and body surface area, and a significant correlation between ventricular mass and lean body mass. When normalized to lean body mass, the ventricular masses of distance runners are found to be significantly higher than those of the other groups, suggesting that dynamic training elevates left ventricular mass compared to static training and no training, while static training increases ventricular mass only to the extent that lean body mass is increased.

Echocardiographic evaluation of simple versus complex congenital heart disease in a tertiary care Paediatrics Hospital

OpenAIRE

Uttam Kumar Sarkar; Anish Chatterjee; Suprit Basu; Atanu Pan; Sumit Periwal

2017-01-01

Background & Objectives:Congenital heart diseases are treatable either by catheter based intervention or open heart surgery according to their quality. In our study we aim to analyze congenital heart disease echocardiographically into simple versus complex heart disease at a tertiary care centre with a public health planning and policy making perspective.Materials & Methods:This hospital based study was done on 1010 patients, both from in-patient and out-patient, who were clinically s...

Prognostic implications of left ventricular mass and geometry following myocardial infarction: the VALIANT (VALsartan In Acute myocardial iNfarcTion) Echocardiographic Study

DEFF Research Database (Denmark)

Verma, Anil; Meris, Alessandra; Skali, Hicham

2008-01-01

associated with RWT was independent of LVMi. CONCLUSIONS: Increased baseline LV mass and abnormal LV geometry portend an increased risk for morbidity and mortality following high-risk myocardial infarction. Concentric LV hypertrophy carries the greatest risk of adverse cardiovascular events including death...... cardiovascular events. METHODS: Quantitative echocardiographic analyses were performed at baseline in 603 patients from the VALIANT (VALsartan In Acute myocardial iNfarcTion) echocardiographic study. The left ventricular mass index (LVMi) and relative wall thickness (RWT) were calculated. Patients were...... classified into 4 mutually exclusive groups based on RWT and LVMi as follows: normal geometry (normal LVMi and normal RWT), concentric remodeling (normal LVMi and increased RWT), eccentric hypertrophy (increased LVMi and normal RWT), and concentric hypertrophy (increased LVMi and increased RWT). Cox...

Cardiovascular abnormalities in patients with oral cleft: a clinical-electrocardiographic-echocardiographic study

Directory of Open Access Journals (Sweden)

Gisele C.P. Leite

2018-04-01

Full Text Available OBJECTIVES: The present study aims to describe the clinical, electrocardiographic, and echocardiographic cardiological findings in a group of patients with oral clefts. METHODS: This is a prospective cross-sectional study on 70 children (age range from 13 days to 19 years with oral clefts who attended the multidisciplinary program of a university hospital from March 2013 to September 2014. The patients were evaluated by a pediatric cardiologist and underwent detailed anamnesis, physical examination, electrocardiogram, and echocardiogram. RESULTS: Sixty percent of the patients were male; 55.7% presented with cleft lip and palate, and 40.0% presented with health complaints. Comorbidities were found in 44.3%. Relevant pregnancy, neonatal, family and personal antecedents were present in 55.7%, 27.1%, 67.2%, and 24.3% of the patients, respectively. Regarding the antecedents, 15.2% of the patients presented with a cardiac murmur, 49.0% with a familial risk of developing plurimetabolic syndrome, and 6% with family antecedents of rheumatic fever. Electrocardiographic evaluation showed one case of atrioventricular block. Echocardiograms were abnormal in 35.7% of the exams, including 5 cases of mitral valve prolapse — one of which was diagnosed with rheumatic heart disease. CONCLUSION: The finding of a family risk of developing plurimetabolic syndrome and a diagnosis of rheumatic heart disease indicates that patients with oral clefts may be more prone to developing acquired heart disease. Thus, our findings highlight the importance of anamnesis and methodological triangulation (clinical-electrocardiographic-echocardiographic in the investigation of patients with oral clefts and emphasize that cardiological follow-up to evaluate acquired and/or rhythm heart diseases is necessary. This strategy permits comorbidity prevention and individualized planned treatment.

Echocardiographic assessment of right ventricular functions in healthy subjects who migrated from the sea level to a moderate altitude.

Science.gov (United States)

Arısoy, Arif; Topçu, Selim; Demirelli, Selami; Altunkaş, Fatih; Karayakalı, Metin; Çelik, Ataç; Tanboğa, İbrahim Halil; Aksakal, Enbiya; Sevimli, Serdar; Gürlertop, Hanefi Yekta

2015-11-25

The aim of this study was to evaluate right ventricle (RV) functions using echocardiography in healthy subjects who migrated from the sea level to moderate altitude (1890 m). The prospective observational in this study population consisted of 33 healthy subjects (23 men; mean age 20.4±3.2 years) who migrated from the sea level to a moderate altitude (Erzurum city centre, 1890 m above sea level) for long-term stay. Subjects underwent echocardiographic evaluation within the first 48 h of exposure to the moderate altitude and at the sixth month of arrival. Conventional echocardiographic parameters such as RV sizes and areas, systolic, and diastolic functional indices [fractional area change (FAC), tricuspid flow velocities, myocardial performance index (MPI), and tricuspid annular plane systolic excursion (TAPSE)] were obtained. Systolic (S) and diastolic (E', A') velocities were acquired from the apical fourchamber view using tissue Doppler imaging. Kolmogorov-Smirnov test, student's t-test, Wilcoxon test, and chi-square test were used in this study. There were no significant changes in RV size, FAC, MPI, TAPSE, inferior inspiratory vena cava collapse, tricuspid E velocity, and tricuspid annulus E' velocity. Compared with the baseline, there was a significant increase in mean pulmonary artery pressure (p=0.001); RV end systolic area (p=0.014); right atrial end diastolic area (p=0.021); tricuspid A velocity (p=0.013); tricuspid annulus S and A' velocity (p=0.031 and p=0.006, respectively); and RV free wall S, E', and A' velocity (p=0.007, pa significant decrease in tricuspid E/A ratio (1.61±0.3 vs. 1.45±0.2, p=0.038) and tricuspid annulus E'/A' ratio (1.52±0.5 vs. 1.23±0.4, p=0.002) at the sixth month. Our study revealed that right ventricular diastolic function was altered while the systolic function was preserved in healthy subjects who migrated from the sea level to a moderate altitude.

Performance evaluation of compounding and directional beamforming techniques for carotid strain imaging using plane wave transmissions

DEFF Research Database (Denmark)

Hansen, Hendrik H.G.; Stuart, Matthias Bo; Villagómez Hoyos, Carlos Armando

2014-01-01

Carotid strain imaging in 3D is not possible with conventional focused imaging, because the frame rate is too low. Plane wave ultrasound provides sufficiently high frame rates, albeit at t he cost of image quality, especially in the off - axis direction due to the lack of focusing . Multiple...... techniques have been developed to cope with the low off - axis image quality when performing 2D (and in future 3D) motion estimation: cross correlation with directional beamforming (with or without RF (coherent) compounding) and displacement compounding. This study compares the precision of these techniques...... with RF compounding and 2D displacement compounding with θ = ~20 ° per formed equally and best with a relative root - mean - squared error of ~2% with respect to the analytical solution . The mean and standard deviation of the estimated motion direction for 2D displacement compounding with θ = 20 ° was 0...

Alterações ecocardiográficas em doentes asmáticos Echocardiograph alterations in asthma patients

Directory of Open Access Journals (Sweden)

André Luís Mancini

2008-06-01

Full Text Available Introdução: A asma é uma doença inflamatória crónica cuja prevalência vem aumentando nos últimos 20 anos. Demanda grande utilização de recursos, principalmente no grupo grave. Neste, há consumo crónico de corticóides inalatórios e de β2-agonistas, que podem produzir uma série de problemas. O objectivo deste trabalho é o de rastrear as alterações electro e ecocardiográficas e relacioná-las ao grau da asma. Metodologia: Selecionámos 87 doentes do ambulatório de asma do HUGG, que, por rotina, possuem uma espirografia, um eletrocardiograma (ECG e um ecocardiograma (ECO feitos com um intervalo máximo de um mês. As alterações ecocardiográficas encontradas foram relacionadas com o grau da asma. Foram usadas estatísticas não paramétricas para essas comparações. Resultados: Encontrámos diferenças significativas (p≤ 0,05 quanto à idade, tempo de asma e saturação da hemoglobina (SaO2 entre os grupos leve e grave. Na amostra, foi identificada alta prevalência de insuficiência tricúspide (41,4%. Conclusões: O ECO identificou uma série de anormalidades, dependentes ou não da gravidade da asma. O ECO pode identificar a hipertensão arterial pulmonar, pelo cálculo da pressão média da artéria pulmonar.Introduction: Asthma is a chronic inflammatory disease which has increased during the last 20 years, putting a strain on medical resources, particularly severe forms of the disease. Treatment in such cases is inhaled corticosteroids and beta agonist drugs that can produce a range of side effects. The aim of this study is to identify echocardiograph abnormalities and correlate them with severity of disease. Methodology: Eight-seven outpatients were selected at the asthma unit of the Gaffrée Guinle University Hospital (HUGG. Each patient underwent spirometry, electrocardiogram (ECG and echocardiogram (ECO during the trial within a month maximum. Echocardiograph abnormalities found related to degree of asthma

Echocardiographic evaluation of patients with systemic lupus erythematosus

International Nuclear Information System (INIS)

Hameed, S.; Malik, L.M.

2007-01-01

Cardiac disease occurs in various forms and is a common cause of death in systemic lupus erythematosus. The objective was to detect cardiac abnormalities by transthoracic echocardiography and determine their association in SLE patients. We conducted a transthoracic echocardiographic study in 48 inpatients with systemic lupus erythematosus. Clinical and serological evaluation to confirm the diagnosis of lupus was done in all patients. There were 44 women (91.6%) and 4 men with a mean age of 26 years. Anti ds DNA was positive in 34 patients (68.75%). Transthoracic echocardiography revealed abnormality in 28 patients (58.33%). Of these, 16 patients (57%) had pericardial involvement with variable amount of effusion. Twelve patients (43%) had some valvular involvement and some degree of myocardial systolic dysfunction was found in 12 patients (43%). Only 4 patients (14%) had all three abnormalities. Anti ds DNA was positive in 71% of patients with cardiac abnormalities. Cardiac involvement is common in patients with systemic lupus erythematosus. Serological abnormalities had an association with cardiac abnormalities, and were found to be more prevalent in young patients. (author)

Optimal Analysis of Left Atrial Strain by Speckle Tracking Echocardiography: P-wave versus R-wave Trigger.

Science.gov (United States)

Hayashi, Shuji; Yamada, Hirotsugu; Bando, Mika; Saijo, Yoshihito; Nishio, Susumu; Hirata, Yukina; Klein, Allan L; Sata, Masataka

2015-08-01

Left atrial (LA) strain analysis using speckle tracking echocardiography is useful for assessing LA function. However, there is no established procedure for this method. Most investigators have determined the electrocardiographic R-wave peak as the starting point for LA strain analysis. To test our hypothesis that P-wave onset should be used as the starting point, we measured LA strain using 2 different starting points and compared the strain values with the corresponding LA volume indices obtained by three-dimensional (3D) echocardiography. We enrolled 78 subjects (61 ± 17 years, 25 males) with and without various cardiac diseases in this study and assessed global longitudinal LA strain by two-dimensional speckle tracking strain echocardiography using EchoPac software. We used either R-wave peak or P-wave onset as the starting point for determining LA strains during the reservoir (Rres, Pres), conduit (Rcon, Pcon), and booster pump (Rpump, Ppump) phases. We determined the maximum, minimum, and preatrial contraction LA volumes, and calculated the LA total, passive, and active emptying fractions using 3D echocardiography. The correlation between Pres and LA total emptying fraction was better than the correlation between Rres and LA total emptying fraction (r = 0.458 vs. 0.308, P = 0.026). Pcon and Ppump exhibited better correlation with the corresponding 3D echocardiographic parameters than Rcon (r = 0.560 vs. 0.479, P = 0.133) and Rpump (r = 0.577 vs. 0.345, P = 0.003), respectively. LA strain in any phase should be analyzed using P-wave onset as the starting point rather than R-wave peak. © 2014, Wiley Periodicals, Inc.

Prevalence of rheumatic valvular heart disease in Rwandan school children: echocardiographic evaluation using the World Heart Federation criteria

Science.gov (United States)

Mucumbitsi, J; Bulwer, B; Mutesa, L; Ndahindwa, MD, MSc; Semakula, M; Rusingiza, E; Arya, P; Breakey, S; Patton-Bolman, C; Kaplan, E L

2017-01-01

Summary Background: Rheumatic fever (RF) and rheumatic valvular heart disease (RHD) remain important medical, surgical and public health concerns in many parts of the world, especially in sub-Saharan Africa. However, there are no published data from Rwanda. We performed a RHD prevalence study in a randomly selected sample of Rwandan school children using the 2012 World Heart Federation (WHF) criteria. Methods: Echocardiographic assessment of 2 501 Rwandan school children from 10 schools in the Gasabo district near Kigali was carried out. Resulting data were evaluated by four experienced echocardiographers. Statistical analyses were carried out by statisticians. Results: RHD prevalence was 6.8/1 000 children examined (95% CI: 4.2/1 000–10.9/1 000). Seventeen met WHF criteria for RHD, 13 fulfilled criteria for ‘borderline’ RHD and four were ‘definite’ RHD. None of these 17 had been previously identified. Conclusion: These data indicate a significant burden of RHD in Rwanda and support a need for defined public health RF control programmes in children there. PMID:28252675

Does the routine echocardiographic exam have a role in the detection and evaluation of cholelithiasis and gallbladder wall thickening?

Science.gov (United States)

Daly, David D; El-Shurafa, Haytham; Nanda, Navin C; Dumaswala, Bhavin; Dumaswala, Komal; Kumar, Nilay; Mutluer, Ferit Onur

2012-09-01

Cholelithiasis is a very common disease in the United States. Most cases remain asymptomatic but a fraction of these patients can develop serious complications such as cholecystitis which may lead to gallbladder perforation and gallbladder cancer which is much less common. Here, we present three cases of cholelithiasis where transthoracic echocardiography was performed routinely. In each case, echocardiography detected cholelithiasis which prompted three-dimensional (3D) echocardiographic evaluation. Three-dimensional echocardiography allowed for more comprehensive examination of the gallbladder shape, size, and wall thickening and the measurement and composition of the stones in three dimensions, measurement of stone volumes, and minimized shadowing produced by stone calcifications. These cases suggest that routine echocardiography has value in detecting gallstones and that 3D echocardiography has incremental value over two-dimensional echocardiography due to pyramidal data sets which allow sequential slicing through the gallbladder and full gallbladder examination without a technologist who is trained in gallbladder imaging. These pyramidal data sets can be further viewed and cropped by a radiologist specialized in abdominal ultrasound. © 2012, Wiley Periodicals, Inc.

Left atrial function to identify patients with atrial fibrillation at high risk of stroke: new insights from a large registry.

Science.gov (United States)

Leung, Melissa; van Rosendael, Philippe J; Abou, Rachid; Ajmone Marsan, Nina; Leung, Dominic Y; Delgado, Victoria; Bax, Jeroen J

2018-04-21

Atrial fibrillation (AF) is an independent risk factor for ischaemic stroke. The CHA2DS2-VASc is the most widely used risk stratification model; however, echocardiographic refinement may be useful, particularly in low risk AF patients. The present study examined the association between advanced echocardiographic parameters and ischaemic stroke, independent of CHA2DS2-VASc score. One thousand, three hundred and sixty-one patients (mean age 65±12 years, 74% males) with first diagnosis of AF and baseline transthoracic echocardiogram were followed by chart review for the occurrence of stroke over a mean of 7.9 years. Left atrial (LA) volumes, LA reservoir strain, P-wave to A' duration on tissue Doppler imaging (PA-TDI, reflecting total atrial conduction time), and left ventricular (LV) global longitudinal strain (GLS) were evaluated in patients with and without stroke. The independent association of these echocardiographic parameters with the occurrence of ischaemic stroke was evaluated with Cox proportional hazard models. One-hundred patients (7%) developed an ischaemic stroke, representing an annualized stroke rate of 0.9%. The incident stroke rate in the year following the first diagnosis of AF was 2.6% in the entire population and higher than the remainder of the follow-up period. Left atrial reservoir (14.5% vs. 18.9%, P = 0.005) and conduit strains were reduced (10.5% vs. 13.5%, P = 0.013), and PA-TDI lengthened (166 ms vs. 141 ms, P Left atrial reservoir strain and PA-TDI were independently associated with risk of stroke in a model including CHA2DS2-VASc score, age, and anticoagulant use. The assessment of LA reservoir strain and PA-TDI on echocardiography after initial CHA2DS2-VASc scoring provides additional risk stratification for stroke and may be useful to guide decisions regarding anticoagulation for patients upon first diagnosis of AF.

Resimulation of noise: a precision estimator for least square error curve-fitting tested for axial strain time constant imaging

Science.gov (United States)

Nair, S. P.; Righetti, R.

2015-05-01

Recent elastography techniques focus on imaging information on properties of materials which can be modeled as viscoelastic or poroelastic. These techniques often require the fitting of temporal strain data, acquired from either a creep or stress-relaxation experiment to a mathematical model using least square error (LSE) parameter estimation. It is known that the strain versus time relationships for tissues undergoing creep compression have a non-linear relationship. In non-linear cases, devising a measure of estimate reliability can be challenging. In this article, we have developed and tested a method to provide non linear LSE parameter estimate reliability: which we called Resimulation of Noise (RoN). RoN provides a measure of reliability by estimating the spread of parameter estimates from a single experiment realization. We have tested RoN specifically for the case of axial strain time constant parameter estimation in poroelastic media. Our tests show that the RoN estimated precision has a linear relationship to the actual precision of the LSE estimator. We have also compared results from the RoN derived measure of reliability against a commonly used reliability measure: the correlation coefficient (CorrCoeff). Our results show that CorrCoeff is a poor measure of estimate reliability for non-linear LSE parameter estimation. While the RoN is specifically tested only for axial strain time constant imaging, a general algorithm is provided for use in all LSE parameter estimation.

Endocardial Device Leads in Patients with Patent Foramen Ovale: Echocardiographic Correlates of Stroke/TIA and Mortality.

Science.gov (United States)

Ponamgi, Shiva P; Vaidya, Vaibhav R; Desimone, Christopher V; Noheria, Amit; Hodge, David O; Slusser, Joshua P; Ammash, Naser M; Bruce, Charles J; Rabinstein, Alejandro A; Friedman, Paul A; Asirvatham, Samuel J

2017-03-01

Echocardiographically detected patent foramen ovale (PFO) has been associated with stroke/transient ischemic attack (TIA) in patients with cardiac implantable electronic devices (CIEDs). We sought to evaluate the relationship between echocardiographic characteristics and risk of stroke/TIA and mortality in CIED patients with PFO. In 6,086 device patients, PFO was detected in 319 patients. A baseline echocardiogram was present in 250 patients, with 186 having a follow-up echocardiogram. Of 250 patients with a baseline echocardiogram, 9.6% (n = 24) had a stroke/TIA during mean follow-up of 5.3 ± 3.1 years; and 42% (n = 105) died over 7.1 ± 3.7 years. Atrial septal aneurysm, prominent Eustachian valve, visible shunting across PFO, baseline or change in estimated right ventricular systolic pressure (RVSP)/tricuspid regurgitation (TR), or maximum RVSP were not associated with postimplant stroke/TIA (P > 0.05). An exploratory multivariate analysis using time-dependent Cox models showed increased hazard of death in patients with increase in TR ≥2 grades (hazard ratio [HR] 1.780, 95% confidence interval [CI] 1.447-2.189, P 10 mm Hg (HR 2.018, 95% CI 1.593-2.556, P TIA. However, a significantly higher TR or RVSP was associated with higher mortality. © 2016 Wiley Periodicals, Inc.

The value of right ventricular longitudinal strain in the evaluation of adult patients with repaired tetralogy of Fallot: a new tool for a contemporary challenge.

Science.gov (United States)

Almeida-Morais, Luís; Pereira-da-Silva, Tiago; Branco, Luísa; Timóteo, Ana T; Agapito, Ana; de Sousa, Lídia; Oliveira, José A; Thomas, Boban; Jalles-Tavares, Nuno; Soares, Rui; Galrinho, Ana; Cruz-Ferreira, Rui

2017-04-01

The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients. Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method. In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all ptetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.

Congenital Heart Diseases in the Newborns of Diabetic Mothers: an Echocardiographic Study

Directory of Open Access Journals (Sweden)

S Rahimpour

2011-10-01

Full Text Available Introduction: Despite the discovery of insulin and current improvement in diabetics care, congenital malformations in diabetics are still more frequent than in the general population. The aim of this study was to identify congenital heart dieases (CHD in the newborns of diabetic mothers (IDMS. Methods: In our prospective study, color doppler echocardiography was performed in 75 consecutive full- term newborns of diabetic mothers by GE Vivid3 echocardiographic device. Newborns were classified into two subgroups according to the type of the mothers’ diabetes: pre-gestational and gestational. They were also those were classified into three subgroups according to their birth weight: appropriate, large and small for gestational age. Data analysis was made by Fisher exact test and Chi-Square test. Results: Forty nine (65% and thirty six (35% of subjects were infants of gestational (IGDM and pre-gestational diabetic mothers (IPDM, respectively. Fifty five Newborns (73% were apropriate, fourteen (19% were large and six (8% were small for gestational age. The most common echocardiographic findings included: patent ductus arteriosus (PDA: 54.7%, hypertrophic cardiomyopathy (HCMP: 24%, ventricular septal defect (VSD: 4%, atrial septal defect (ASD: 2.7%, transposition of great arteries (TGA: 1.3% and coarctation of the Aorta (COA: 1.3%. Overall incidence of congenital heart diseases was 9.3 after exclusion of PDA and HCMP cases. The incidence of congenital heart diseases was higher in macrosomic than nonmacrosomic infants of diabetic mothers (P<0.001. Congenital heart diseases were more common in infants of pre-gestational than gestational diabetic mothers (P=0.004. Conclusion: Our results showed that diabetic mothers are at increased risk of giving birth to a newborn with congenital heart disease, and transthoracic echocardiography is recommended for all infants of diabetic mothers.

Measurement of Strain and Strain Rate during the Impact of Tennis Ball Cores

Directory of Open Access Journals (Sweden)

Ben Lane

2018-03-01

Full Text Available The aim of this investigation was to establish the strains and strain rates experienced by tennis ball cores during impact to inform material characterisation testing and finite element modelling. Three-dimensional surface strains and strain rates were measured using two high-speed video cameras and corresponding digital image correlation software (GOM Correlate Professional. The results suggest that material characterisation testing to a maximum strain of 0.4 and a maximum rate of 500 s−1 in tension and to a maximum strain of −0.4 and a maximum rate of −800 s−1 in compression would encapsulate the demands placed on the material during impact and, in turn, define the range of properties required to encapsulate the behavior of the material during impact, enabling testing to be application-specific and strain-rate-dependent properties to be established and incorporated in finite element models.

Right heart function in impaired left ventricular diastolic function: 2D speckle tracking echocardiography-based and Doppler tissue imaging-based analysis of right atrial and ventricular function.

Science.gov (United States)

Brand, Anna; Bathe, Marny; Oertelt-Prigione, Sabine; Seeland, Ute; Rücke, Mirjam; Regitz-Zagrosek, Vera; Stangl, Karl; Knebel, Fabian; Stangl, Verena; Dreger, Henryk

2018-01-01

The aim of our study was to describe right atrial (RA) and right ventricular (RV) function, assessed by Doppler tissue imaging and 2D speckle tracking echocardiography (2DSTE), in women with signs of early impaired left ventricular diastolic function (DD). In a cross-sectional trial, standard parameters of diastolic and right heart function were investigated in 438 women of the Berlin Female Risk Evaluation (BEFRI) study. In a subset of women, average peak systolic RA strain (RAS), as well as the average peak systolic RV strain of the free wall (RVS free wall) and of all RV segments (average RV strain; RVS Avg), was analyzed using 2DSTE. Compared to women with normal diastolic function (DD0), RAS, RVS free wall and RVS Avg were significantly reduced in DD (43.1% ± 11.9%, -26.7% ± 5.6%, and -23.3% ± 3.5% in DD0; vs 35.1% ± 10.4%, -23.9% ± 5.5%, and -20.6% ± 3.8% in DD; P right heart function is significantly altered in DD. DTI as well as 2DSTE constitute sensitive echocardiographic tools that enable the diagnosis of impaired right heart mechanics in early-staged DD. © 2017 Wiley Periodicals, Inc.

Using optical full-field measurement based on digital image correlation to measure strain on a tree subjected to mechanical load

Czech Academy of Sciences Publication Activity Database

Sebera, V.; Praus, L.; Tippner, J.; Kunecký, Jiří; Čepela, J.; Wimmer, R.

2014-01-01

Roč. 28, č. 4 (2014), s. 1173-1184 ISSN 0931-1890 Institutional support: RVO:68378297 Keywords : digital image correlation * tree biomechanics * strain * pulling test * arboriculture * nondestructive Subject RIV: JJ - Other Materials Impact factor: 1.651, year: 2014

Quantification of green fluorescent protein by in vivo imaging, PCR, and flow cytometry: comparison of transgenic strains and relevance for fetal cell microchimerism.

Science.gov (United States)

Fujiki, Yutaka; Tao, Kai; Bianchi, Diana W; Giel-Moloney, Maryann; Leiter, Andrew B; Johnson, Kirby L

2008-02-01

Animal models are increasingly being used for the assessment of fetal cell microchimerism in maternal tissue. We wished to determine the optimal transgenic mouse strain and analytic technique to facilitate the detection of rare transgenic microchimeric fetal cells amongst a large number of maternal wild-type cells. We evaluated two strains of mice transgenic for the enhanced green fluorescent protein (EGFP): a commercially available, commonly used strain (C57BL/6-Tg(ACTB-EGFP)10sb/J) (CAG) and a newly created strain (ROSA26-EGFP) using three different techniques: in vivo and ex vivo fluorescent imaging (for whole body and dissected organs, respectively), PCR amplification of gfp, and flow cytometry (FCM). By fluorescent imaging, organs from CAG mice were 10-fold brighter than organs from ROSA26-EGFP mice (P characteristics that make it useful under specific experimental circumstances. The CAG mouse model is preferable when experiments require brighter cells, whereas ROSA26-EGFP is more appropriate when uniform or ubiquitous expression is more important than brightness. Investigators must carefully select the transgenic strain most suited to the experimental design to obtain the most consistent and reproducible data. In vivo imaging allows for phenotypic evaluation of whole animals and intact organs; however, we did not evaluate its utility for the detection of rare, fetal microchimeric cells in the maternal organs. Finally, while PCR amplification of a paternally inherited transgene does allow for the quantitative determination of rare microchimeric cells, FCM allows for both quantitative and qualitative evaluations of fetal cells at very high sensitivity in a plethora of maternal organs. (c) 2008 International Society for Analytical Cytology

Prognostic implications of fasting plasma glucose in subjects with echocardiographic abnormalities

DEFF Research Database (Denmark)

Pareek, Manan; Vaduganathan, Muthiah; Bhatt, Deepak L

2017-01-01

AIMS: To examine whether baseline fasting plasma glucose (FPG) modifies the prognostic role of left ventricular (LV) mass, geometric pattern, and diastolic function, for prediction of cardiovascular morbidity and mortality. METHODS: Population-based cohort study comprising of 1047 men and 456 women...... proportional-hazards regression with interaction analysis was used to evaluate the risk associated with FPG and LV structure and function. RESULTS: Median age was 67years, and 31% had impaired fasting glucose, 31% diabetes, 17% LV hypertrophy, and 40% diastolic dysfunction. During a median follow-up duration.......001), and with the association between diastolic dysfunction and event risk (P=0.02), including grade 2 or 3 dysfunction (P=0.04). CONCLUSIONS: Echocardiographic abnormalities were more strongly associated with an adverse prognosis among subjects with impaired fasting glucose or diabetes....

Blind Source Parameters for Performance Evaluation of Despeckling Filters

Directory of Open Access Journals (Sweden)

Nagashettappa Biradar

2016-01-01

Full Text Available The speckle noise is inherent to transthoracic echocardiographic images. A standard noise-free reference echocardiographic image does not exist. The evaluation of filters based on the traditional parameters such as peak signal-to-noise ratio, mean square error, and structural similarity index may not reflect the true filter performance on echocardiographic images. Therefore, the performance of despeckling can be evaluated using blind assessment metrics like the speckle suppression index, speckle suppression and mean preservation index (SMPI, and beta metric. The need for noise-free reference image is overcome using these three parameters. This paper presents a comprehensive analysis and evaluation of eleven types of despeckling filters for echocardiographic images in terms of blind and traditional performance parameters along with clinical validation. The noise is effectively suppressed using the logarithmic neighborhood shrinkage (NeighShrink embedded with Stein’s unbiased risk estimation (SURE. The SMPI is three times more effective compared to the wavelet based generalized likelihood estimation approach. The quantitative evaluation and clinical validation reveal that the filters such as the nonlocal mean, posterior sampling based Bayesian estimation, hybrid median, and probabilistic patch based filters are acceptable whereas median, anisotropic diffusion, fuzzy, and Ripplet nonlinear approximation filters have limited applications for echocardiographic images.

Blind Source Parameters for Performance Evaluation of Despeckling Filters.

Science.gov (United States)

Biradar, Nagashettappa; Dewal, M L; Rohit, ManojKumar; Gowre, Sanjaykumar; Gundge, Yogesh

2016-01-01

The speckle noise is inherent to transthoracic echocardiographic images. A standard noise-free reference echocardiographic image does not exist. The evaluation of filters based on the traditional parameters such as peak signal-to-noise ratio, mean square error, and structural similarity index may not reflect the true filter performance on echocardiographic images. Therefore, the performance of despeckling can be evaluated using blind assessment metrics like the speckle suppression index, speckle suppression and mean preservation index (SMPI), and beta metric. The need for noise-free reference image is overcome using these three parameters. This paper presents a comprehensive analysis and evaluation of eleven types of despeckling filters for echocardiographic images in terms of blind and traditional performance parameters along with clinical validation. The noise is effectively suppressed using the logarithmic neighborhood shrinkage (NeighShrink) embedded with Stein's unbiased risk estimation (SURE). The SMPI is three times more effective compared to the wavelet based generalized likelihood estimation approach. The quantitative evaluation and clinical validation reveal that the filters such as the nonlocal mean, posterior sampling based Bayesian estimation, hybrid median, and probabilistic patch based filters are acceptable whereas median, anisotropic diffusion, fuzzy, and Ripplet nonlinear approximation filters have limited applications for echocardiographic images.

Magnetic resonance and diffusion tensor imaging analyses indicate heterogeneous strains along human medial gastrocnemius fascicles caused by submaximal plantar-flexion activity.

Science.gov (United States)

Karakuzu, Agah; Pamuk, Uluç; Ozturk, Cengizhan; Acar, Burak; Yucesoy, Can A

2017-05-24

Sarcomere length changes are central to force production and excursion of skeletal muscle. Previous modeling indicates non-uniformity of that if mechanical interaction of muscle with its surrounding muscular and connective tissues is taken into account. Hence, quantifying length changes along the fascicles of activated human muscle in vivo is crucial, but this is lacking due to technical complexities. Combining magnetic resonance imaging deformation analyses and diffusion tensor imaging tractography, the aim was to test the hypothesis that submaximal plantar flexion activity at 15% MVC causes heterogeneous length changes along the fascicles of human medial gastrocnemius (GM) muscle. A general fascicle strain distribution pattern shown for all subjects indicates that proximal track segments are shortened, whereas distal ones are lengthened (e.g., by 13% and 29%, respectively). Mean fiber direction strains of different tracts also shows heterogeneity (for up to 57.5% of the fascicles). Inter-subject variability of amplitude and distribution of fascicle strains is notable. These findings confirm the hypothesis and are solid indicators for the functionally dependent mechanics of human muscle, in vivo. Heterogeneity of fascicle strains can be explained by epimuscular myofascial force transmission. To the best of our knowledge, this is the first study, which quantified local deformations along human skeletal muscle fascicles caused by sustained submaximal activation. The present approach and indicated fascicle strain heterogeneity has numerous implications for muscle function in health and disease to estimate the muscle's contribution to the joint moment and excursion and to evaluate mechanisms of muscle injury and several treatment techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

Field Strain Measurement on the Fiber Scale in Carbon Fiber Reinforced Polymers Using Global Finite-Element Based Digital Image Correlation

KAUST Repository

Tao, Ran

2015-01-01

is aimed to accurately measure the displacement and strain fields at the fiber-matrix scale in a cross-ply composite. First, the theories of both local subset-based digital image correlation (DIC) and global finite-element based DIC are outlined. Second, in

Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE.

Science.gov (United States)

Gao, Hao; Allan, Andrew; McComb, Christie; Luo, Xiaoyu; Berry, Colin

2014-07-07

Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (- 0.18 ± 0.04 versus - 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice.

Digital image correlation analysis of local strain fields on Ti6Al4V manufactured by electron beam melting

Energy Technology Data Exchange (ETDEWEB)

Karlsson, Joakim, E-mail: Joakim.karlsson@sp.se [SP Technical Research Institute of Sweden, Box 857, SE-501 15, Borås (Sweden); Division of Applied Materials Science, Department of Engineering Sciences, Ångström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden); Sjögren, Torsten [SP Technical Research Institute of Sweden, Box 857, SE-501 15, Borås (Sweden); Snis, Anders [Arcam AB, Krokslätts fabriker 27 A, SE-431 37, Mölndal (Sweden); Engqvist, Håkan [Division of Applied Materials Science, Department of Engineering Sciences, Ångström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden); Lausmaa, Jukka [SP Technical Research Institute of Sweden, Box 857, SE-501 15, Borås (Sweden)

2014-11-17

Additive manufacturing, or 3D-printing as it is often called, build parts in a layer-by-layer fashion. A common concern, regardless of the specific additive manufacturing technique used, is the risk of inadequate fusion between the adjacent layers which in turn may cause inferior mechanical properties. In this work, the local strain properties of titanium parts produced by Electron Beam Melting (EBM{sup ®}) were studied in order to gain information about the quality of fusion of the stock powder material used in the process. By using Digital Image Correlation (DIC) the strain fields in the individual layers were analyzed, as well as the global strain behavior of the bulk material. The results show that fully solid titanium parts manufactured by EBM are homogenous and do not experience local deformation behavior, neither on local nor on a global level.

Digital image correlation analysis of local strain fields on Ti6Al4V manufactured by electron beam melting

International Nuclear Information System (INIS)

Karlsson, Joakim; Sjögren, Torsten; Snis, Anders; Engqvist, Håkan; Lausmaa, Jukka

2014-01-01

Additive manufacturing, or 3D-printing as it is often called, build parts in a layer-by-layer fashion. A common concern, regardless of the specific additive manufacturing technique used, is the risk of inadequate fusion between the adjacent layers which in turn may cause inferior mechanical properties. In this work, the local strain properties of titanium parts produced by Electron Beam Melting (EBM ® ) were studied in order to gain information about the quality of fusion of the stock powder material used in the process. By using Digital Image Correlation (DIC) the strain fields in the individual layers were analyzed, as well as the global strain behavior of the bulk material. The results show that fully solid titanium parts manufactured by EBM are homogenous and do not experience local deformation behavior, neither on local nor on a global level

Strain Distribution in the Anterior Inferior Tibiofibular Ligament, Posterior Inferior Tibiofibular Ligament, and Interosseous Membrane Using Digital Image Correlation.

Science.gov (United States)

Xu, Daorong; Wang, Yibei; Jiang, Chunyu; Fu, Maoqing; Li, Shiqi; Qian, Lei; Sun, Peidong; Ouyang, Jun

2018-05-01

Ligament repair and augmentation techniques can stabilize syndesmosis injuries. However, little is known about the mechanical behavior of syndesmotic ligaments. The aim of this study was to analyze full-field strain, strain trend under foot rotation, and subregional strain differences of the anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), and interosseous membrane (IOM). Eleven fresh-frozen lower limbs were dissected to expose the AITFL, PITFL, and IOM. The foot underwent rotation from 0° to 25° internal and 35° external, with 3 ankle positions (neutral, 15° dorsiflexion, and 25° plantarflexion) and a vertical load of 430 N. Ligament strain was recorded using digital image correlation. The mean strain on the AITFL with 35° external rotation was greater in the proximal portion compared with distal portion in the neutral position ( P = .009) and dorsiflexion ( P = .003). The mean strain in the tibial insertion and midsubstance near tibial insertion were greater when compared with other regions ( P = .018 and P = .009). The subregions of mean strain in the PITFL and IOM groups were not significantly different. The strain trend of AITFL, PITFL, and IOM showed common transformation, just when the foot was externally rotated. The findings of this study show that a significantly high strain was observed on the proximal part and the midsubstance near the Chaput tubercle of the AITFL when the ankle was externally rotated. All 3 ligaments resisted the torque in the syndesmosis by external rotation of the foot. This study allows for better understanding of the mechanical behavior of the syndesmosis ligaments, which could influence the repair technique and AITFL augmentation techniques.

Evaluation of congenital heart disease by three-dimensional MR imaging

International Nuclear Information System (INIS)

Vannier, M.W.; Gutierrez, F.R.; Canter, C.E.; Yoffie, R.L.; Hildebolt, C.F.

1988-01-01

In an evaluation of the detectability of intra-and extracardiac morphologic defects with electrocardiographically gated magnetic resonance (MR) imaging, 100 patients were studied, including ten without and 90 with abnormalities. The abnormalities included septal defects, tetrology of Fallot, pulmonary atresia, transposition of the great vessels, and others. The patients with abnormalities were studied angiographically and with echocardiographic analyses. Two radiologists with cardiac MR imaging experience evaluated the scans in a blinded fashion, and the results were analyzed by means of receiver operating characteristic analysis. The diagnostic value of routine two-dimensional cardiac MR imaging was compared with that of three-dimensional reconstruction imaging and with the results of cardiac catheterization and echocardiography. The reported sensitivity and specificity of echocardiography in the detection of congenital heart disease is comparable to that of MR imaging. The differences in diagnostic value between various modalities for the imaging of congenital heart disease may be determined from the results of the preliminary series

[Comparison of echocardiographic findings in AVS patients with and without high IgG, IgM, IgA titers against Chlamydia pneumoniae during 12 months' observation of AVS natural course].

Science.gov (United States)

Swierszcz, Jolanta; Dubiel, Jacek S; Krzysiek, Józef; Sztefko, Krystyna; Galicka-Latała, Danuta; Roman, Pfitzner; Podolec, Piotr; Wodniecki, Jan

2011-01-01

Comparison of echocardiographic findings in AVS patients with and without high IgG, IgM, IgA titers against Chlamydia pneumoniae during 12 months' observation of AVS natural course. 60 AVS patients who did not agree for operational treatment were divided into group A (30 patients with high IgG titer) group B (30 patients with low IgG titer), group C (22 patients with high IgA titer) group D (38 patients with low IgA titer), group E (7 patients with high IgM titer), group F (53 patients with low IgA titer) Antibodies titers and echocardiographic scans were carried out every 12 months. There were more (p AVS deterioration in group A compared to group B. Group A patients had lower left ventricle posteriori wall systolic diameter compared to group B. There were no differences in echocardiographic parameters between group C and D. Mean ejection fraction was lower and mean right atrium diameter was higher in group E compared to group F. The results may suggest link between Chlamydia pneumoniae and deterioration of AVS.

Field Strain Measurement on the Fiber Scale in Carbon Fiber Reinforced Polymers Using Global Finite-Element Based Digital Image Correlation

KAUST Repository

Tao, Ran

2015-05-01

Laminated composites are materials with complex architecture made of continuous fibers embedded within a polymeric resin. The properties of the raw materials can vary from one point to another due to different local processing conditions or complex geometrical features for example. A first step towards the identification of these spatially varying material parameters is to image with precision the displacement fields in this complex microstructure when subjected to mechanical loading. This thesis is aimed to accurately measure the displacement and strain fields at the fiber-matrix scale in a cross-ply composite. First, the theories of both local subset-based digital image correlation (DIC) and global finite-element based DIC are outlined. Second, in-situ secondary electron tensile images obtained by scanning electron microscopy (SEM) are post-processed by both DIC techniques. Finally, it is shown that when global DIC is applied with a conformal mesh, it can capture more accurately sharp local variations in the strain fields as it takes into account the underlying microstructure. In comparison to subset-based local DIC, finite-element based global DIC is better suited for capturing gradients across the fiber-matrix interfaces.

Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE

International Nuclear Information System (INIS)

Gao, Hao; Luo, Xiaoyu; Allan, Andrew; McComb, Christie; Berry, Colin

2014-01-01

Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (− 0.18 ± 0.04 versus − 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p < 0.01). In the patient study, the peak strain patterns predicted by cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice. (paper)

Echocardiographic evaluation and N-terminal pro-brain natriuretic peptide measurement of patients hospitalized for heart failure during weaning from mechanical ventilation.

Science.gov (United States)

Gerbaud, E; Erickson, M; Grenouillet-Delacre, M; Beauvieux, M-C; Coste, P; Durrieu-Jaïs, C; Hilbert, G; Castaing, Y; Vargas, F

2012-04-01

Weaning patients with heart failure who have required mechanical ventilation remains challenging. We evaluated echocardiographic indexes and N-terminal pro-brain natriuretic peptide (NT-proBNP) as markers of acute cardiac dysfunction before and after spontaneous breathing trials (SBT) in such patients to assess their ability to predict subsequent successful extubation. Forty-four patients who underwent their first SBT were prospectively included. Plasma levels of NT-proBNP and transthoracic echocardiography indices including cardiac index, E/A ratio and E/Ea ratio were recorded immediately before commencing and just before the end of SBT. Ten patients (22.7%) failed their SBT. No significant difference was observed concerning baseline echocardiographic data and NT-proBNP level between the patients who succeeded the SBT or those that failed. Cardiac index increased significantly at end-SBT in patients who passed (3.3 [3.06-3.77] vs. 3 [2.68-3.3] L/min/m(2), Pfailed. E/Ea ratio (16.8 [8.5-27.3] vs. 10.7 [6.7-20.5], P=0.006) and NT-proBNP level (8199 [3106-10949] vs. 4200 [1855-7125] pg/mL, P=0.004) increased significantly in those who failed the SBT, in contrast to the weaning success group where they remained unchanged. Neither NT-proBNP level nor the studied echocardiographic indices before SBT were able to predict SBT outcome in patients presenting with severe heart failure. Failure to increase the cardiac index and increases in both E/Ea ratio and NT-proBNP levels were seen at end-SBT in patients who failed the SBT, and may reflect failure of myocardial reserve to cope with the stress of SBT.

Measurement of stress-strain behaviour of human hair fibres using optical techniques.

Science.gov (United States)

Lee, J; Kwon, H J

2013-06-01

Many studies have presented stress-strain relationship of human hair, but most of them have been based on an engineering stress-strain curve, which is not a true representation of stress-strain behaviour. In this study, a more accurate 'true' stress-strain curve of human hair was determined by applying optical techniques to the images of the hair deformed under tension. This was achieved by applying digital image cross-correlation (DIC) to 10× magnified images of hair fibres taken under increasing tension to estimate the strain increments. True strain was calculated by summation of the strain increments according to the theoretical definition of 'true' strain. The variation in diameter with the increase in longitudinal elongation was also measured from the 40× magnified images to estimate the Poisson's ratio and true stress. By combining the true strain and the true stress, a true stress-strain curve could be determined, which demonstrated much higher stress values than the conventional engineering stress-strain curve at the same degree of deformation. Four regions were identified in the true stress-strain relationship and empirical constitutive equations were proposed for each region. Theoretical analysis on the necking condition using the constitutive equations provided the insight into the failure mechanism of human hair. This analysis indicated that local thinning caused by necking does not occur in the hair fibres, but, rather, relatively uniform deformation takes place until final failure (fracture) eventually occurs. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Echocardiographic knowledge-based reconstruction for quantification of the systemic right ventricle in young adults with repaired D-transposition of great arteries.

Science.gov (United States)

Kutty, Shelby; Li, Ling; Polak, Amanda; Gribben, Paul; Danford, David A

2012-03-15

The systemic right ventricle (RV) in congenital heart disease is susceptible to progressive dilation and dysfunction. A 2-dimensional echocardiographic means for serial monitoring of the RV would be of great value in this clinical setting. We used 2-dimensional echocardiography with knowledge-based reconstruction (2DE-KBR) for evaluation of systemic RV. Patients with d-transposition of great arteries repaired with an atrial switch and without implanted pacemakers were prospectively recruited for same-day 2DE-KBR and cardiac magnetic resonance (CMR) imaging. RV images were acquired in various 2-dimensional imaging planes using a 3-dimensional space-localizing device attached to the imaging transducer and 3-dimensional reconstruction was performed. RV end-diastolic volume, end-systolic volume, and ejection fraction (EF) were calculated and compared to volumetric CMR analysis. Fifteen patients (7 women, 8 men, 24 ± 7 years old, weight 67 ± 12 kg) were studied. There was good agreement of 2DE-KBR and CMR measurements. Mean RV end-diastolic volume was 221 ± 39 ml with 2DE-KBR and 231 ± 35 ml with CMR (r = 0.80); mean end-systolic volume was 129 ± 35 ml with KBR and 132 ± 30 ml with CMR (r = 0.82), and EF was 42 ± 10% with KBR and 43 ± 7% with CMR (r = 0.86). For 2DE-KBR mean interobserver variabilities were 4.6%, 2.6%, and 4.3%; intraobserver variabilities were 3.2%, 3.1%, and 2.3%, respectively, for end-diastolic volume, end-systolic volume, and EF. In conclusion, this study demonstrates the clinical feasibility of quantifying systemic RV volumes and function using 2DE-KBR in adolescents and young adults with repaired d-transposition of great arteries and good agreement of measurements with CMR. Copyright © 2012 Elsevier Inc. All rights reserved.

Left atrial strain: a new parameter for assessment of left ventricular filling pressure.

Science.gov (United States)

Cameli, Matteo; Mandoli, Giulia Elena; Loiacono, Ferdinando; Dini, Frank Lloyd; Henein, Michael; Mondillo, Sergio

2016-01-01

In order to obtain accurate diagnosis, treatment and prognostication in many cardiac conditions, there is a need for assessment of left ventricular (LV) filling pressure. While systole depends on ejection function of LV, diastole and its disturbances influence filling function and pressures. The commonest condition that represents the latter is heart failure with preserved ejection fraction in which LV ejection is maintained, but diastole is disturbed and hence filling pressures are raised. Significant diastolic dysfunction results in raised LV end-diastolic pressure, mean left atrial (LA) pressure and pulmonary capillary wedge pressure, all referred to as LV filling pressures. Left and right heart catheterization has traditionally been used as the gold standard investigation for assessing these pressures. More recently, Doppler echocardiography has taken over such application because of its noninvasive nature and for being patient friendly. A number of indices are used to achieve accurate assessment of filling pressures including: LV pulsed-wave filling velocities (E/A ratio, E wave deceleration time), pulmonary venous flow (S wave and D wave), tissue Doppler imaging (E' wave and E/E' ratio) and LA volume index. LA longitudinal strain derived from speckle tracking echocardiography (STE) is also sensitive in estimating intracavitary pressures. It is angle-independent, thus overcomes Doppler limitations and provides highly reproducible measures of LA deformation. This review examines the application of various Doppler echocardiographic techniques in assessing LV filling pressures, in particular the emerging role of STE in assessing LA pressures in various conditions, e.g., HF, arterial hypertension and atrial fibrillation.

Echocardiographic predictors of coil vs device closure in patients undergoing percutaneous patent ductus arteriosus closure.

Science.gov (United States)

Roushdy, Alaa; Abd El Razek, Yasmeen; Mamdouh Tawfik, Ahmed

2018-01-01

To determine anatomic and hemodynamic echocardiographic predictors for patent ductus arteriosus (PDA) device vs coil closure. Seventy-six patients who were referred for elective transcatheter PDA closure were enrolled in the study. All patients underwent full echocardiogram including measurement of the PDA pulmonary end diameter, color flow width and extent, peak and end-diastolic Doppler gradients across the duct, diastolic flow reversal, left atrial dimensions and volume, left ventricular sphericity index, and volumes. The study group was subdivided into 2 subgroups based on the mode of PDA closure whether by coil (n = 42) or device (n = 34). Using univariate analysis there was a highly significant difference between the 2 groups as regard the pulmonary end diameter measured in both the suprasternal and parasternal short-axis views as well as the color flow width and color flow extent (P closure group had statistically significant higher end-systolic and end-diastolic volumes indexed, left atrial volume, and diastolic flow reversal. Receiver operating characteristic curve analysis showed a pulmonary end diameter cutoff point from the suprasternal view > 2.5 mm and from parasternal short-axis view > 2.61 mm to have the highest balanced sensitivity and specificity to predict the likelihood for device closure (AUC 0.971 and 0.979 respectively). The pulmonary end diameter measured from the suprasternal view was the most independent predictor of device closure. The selection between PDA coil or device closure can be done on the basis of multiple anatomic and hemodynamic echocardiographic variables. © 2017 Wiley Periodicals, Inc.

Changes in Mitral Annular Geometry after Aortic Valve Replacement: A Three-Dimensional Transesophageal Echocardiographic Study

Science.gov (United States)

Mahmood, Feroze; Warraich, Haider J.; Gorman, Joseph H.; Gorman, Robert C.; Chen, Tzong-Huei; Panzica, Peter; Maslow, Andrew; Khabbaz, Kamal

2014-01-01

Background and aim of the study Intraoperative real-time three-dimensional transesophageal echocardiography (RT-3D TEE) was used to examine the geometric changes that occur in the mitral annulus immediately after aortic valve replacement (AVR). Methods A total of 35 patients undergoing elective surgical AVR under cardiopulmonary bypass was enrolled in the study. Intraoperative RT-3D TEE was used prospectively to acquire volumetric echocardiographic datasets immediately before and after AVR. The 3D echocardiographic data were analyzed offline using TomTec® Mitral Valve Assessment software to assess changes in specific mitral annular geometric parameters. Results Datasets were successfully acquired and analyzed for all patients. A significant reduction was noted in the mitral annular area (-16.3%, p <0.001), circumference (-8.9% p <0.001) and the anteroposterior (-6.3%, p = 0.019) and anterolateral-posteromedial (-10.5%, p <0.001) diameters. A greater reduction was noted in the anterior annulus length compared to the posterior annulus length (10.5% versus 62%, p <0.05) after AVR. No significant change was seen in the non-planarity angle, coaptation depth, and closure line length. During the period of data acquisition before and after AVR, no significant change was noted in the central venous pressure or left ventricular end-diastolic diameter. Conclusion The mitral annulus undergoes significant geometric changes immediately after AVR Notably, a 16.3% reduction was observed in the mitral annular area. The anterior annulus underwent a greater reduction in length compared to the posterior annulus, which suggested the existence of a mechanical compression by the prosthetic valve. PMID:23409347

Echocardiographic evaluation of heart in chronic obstructive pulmonary disease patient and its co-relation with the severity of disease

Directory of Open Access Journals (Sweden)

N K Gupta

2011-01-01

Full Text Available Background: Chronic obstructive pulmonary disease (COPD has considerable effects on cardiac functions, including those of the right ventricle, left ventricle, and pulmonary blood vessels. Most of the increased mortality associated with COPD is due to cardiac involvement. Echocardiography provides a rapid, noninvasive, portable, and accurate method to evaluate the cardiac changes. Aims: To assess the cardiac changes secondary to COPD by echocardiography and to find out the correlation between echocardiographic findings and severity of COPD, if there is any. Materials and Methods: A total 40 of patients of COPD were selected and staged by pulmonary function test (PFT and evaluated by echocardiography. Results: On echocardiographic evaluation of COPD, 50% cases had normal echocardiographic parameters. Measurable tricuspid regurgitation (TR was observed in 27/40 cases (67.5%. Pulmonary hypertension (PH, which is defined as systolic pulmonary arterial pressure (sPAP > 30 mmHg was observed in 17/27 (63% cases in which prevalence of mild, moderate, and severe PH were 10/17 (58.82%, 4/17 (23.53%, and 3/17 (17.65%, respectively. The frequencies of PH in mild, moderate, severe, and very severe COPD were 16.67%, 54.55%, 60.00%, and 83.33%, respectively. Right atrial pressure was 10 mmHg in 82.5% cases and 15 mmHg in 17.5% cases. Cor pulmonale was observed in 7/17 (41.17% cases; 7.50% cases had left ventricle (LV systolic dysfunction and 47.5% cases had evidence of LV diastolic dysfunction defined as A ≥ E (peak mitral flow velocity of the early rapid filling wave (E, peak velocity of the late filling wave caused by atrial contraction (A on mitral valve tracing. Left ventricle hypertrophy was found in 22.5% cases. Conclusion : Prevalence of PH has a linear relationship with severity of COPD and severe PH is almost associated with cor pulmonale. Echocardiography helps in early detection of cardiac complications in COPD cases giving time for early

Echocardiographic findings predict in-hospital and 1-year mortality in left-sided native valve Staphylococcus aureus endocarditis

DEFF Research Database (Denmark)

Lauridsen, Trine K.; Park, Lawrence; Tong, Steven Y C

2015-01-01

BACKGROUND: Staphylococcus aureus left-sided native valve infective endocarditis (LNVIE) has higher complication and mortality rates compared with endocarditis from other pathogens. Whether echocardiographic variables can predict prognosis in S aureus LNVIE is unknown. METHODS AND RESULTS......: Consecutive patients with LNVIE, enrolled between January 2000 and September 2006, in the International Collaboration on Endocarditis were identified. Subjects without S aureus IE were matched to those with S aureus IE by the propensity of having S aureus. Survival differences were determined using log...

Bragg-edge neutron transmission strain tomography for in situ loadings

Energy Technology Data Exchange (ETDEWEB)

Wensrich, C.M., E-mail: christopher.wensrich@newcastle.edu.au [School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Hendriks, J.N.; Gregg, A. [School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Meylan, M.H. [School of Mathematical and Physical Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia); Luzin, V. [Bragg Institute, Australian Nuclear Science and Technology Organisation (ANSTO), Kirrawee, NSW 2232 (Australia); Tremsin, A.S. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)

2016-09-15

An approach for tomographic reconstruction of three-dimensional strain distributions from Bragg-edge neutron transmission strain images is outlined and investigated. This algorithm is based on the link between Bragg-edge strain measurements and the Longitudinal Ray Transform, which has been shown to be sensitive only to boundary displacement. By exploiting this observation we provide a method for reconstructing boundary displacement from sets of Bragg-edge strain images. In the case where these displacements are strictly the result of externally applied tractions, corresponding internal strain fields can then be found through traditional linear-static finite element methods. This approach is tested on synthetic data in two-dimensions, where the rate of convergence in the presence of measurement noise and beam attenuation is examined.

Concordance and reproducibility between M-mode, tissue Doppler imaging, and two-dimensional strain imaging in the assessment of mitral annular displacement and velocity in patients with various heart conditions

DEFF Research Database (Denmark)

de Knegt, Martina Chantal; Biering-Sorensen, Tor; Sogaard, Peter

2014-01-01

AIMS: Mitral annular (MA) displacement reflects longitudinal left ventricular (LV) deformation and systolic velocity measurements reflect the rate of contraction; both are valuable in the diagnosis and prognosis of cardiac disease. The aim of this study was to test the agreement and reproducibility...... between motion mode (M-mode), colour tissue Doppler imaging (TDI), and two-dimensional strain imaging (2DSI) when measuring MA displacement and systolic velocity. METHODS AND RESULTS: Using GE Healthcare Vivid 7 and E9 and Echopac BT11 software, MA displacement and velocity measurements by 2DSI, TDI...

Electrocardiographic, echocardiographic, and indirect blood pressure evaluation in dogs subjected to different sedation protocols

Directory of Open Access Journals (Sweden)

Helena Mondardo Cardoso

Full Text Available ABSTRACT: The present study aimed to evaluate the effects of different sedation protocols on blood pressure and echocardiographic and electrocardiographic parameters in dogs. In total, 24 male mixed-breed dogs with a mean weight of 9.87±3.0kg were used.Animals were randomly divided into four groups (n=6, which were subjected to sedation using the following protocols: acepromazine (0.05mgkg-1 and butorphanol (0.3mgkg-1 (AB; acepromazine (0.05mgkg-1and methadone (0.5mgkg-1 (AM; acepromazine (0.03mgkg-1, methadone (0.5mgkg-1, and midazolam (0.3mgkg-1(MAM; and methadone only (0.5mgkg-1 (M. Indirect blood pressure (BP measurements and computerized electrocardiography (ECG and echocardiography (ECO were performed immediately before the application of the sedation protocol (baseline, and the same evaluations were repeated after 15 minutes. BP decreased in groups AB, MAM, and AM compared to baseline values. Electrocardiographic measurements showed decreased heart rates (HRs after sedation in all groups, and bradycardia was observed after sedation in two dogs from group M and one animal from group AM. The P-wave duration increased after sedation in groups AM and M. After sedation, no changes in cardiac dimensions were revealed byECO.Fractional shortening (FS decreased after sedation in the AM group, and dogs from group AB exhibited a smaller decrease in FS compared with the other groups. The cardiac index (CI was lower in groups AM and M than in the other groups. Animals from group AB were less resistant to examination and exhibited the most favorable sedation scores. It was concluded that the combination of acepromazine and butorphanol was the best sedation protocol for performing echocardiogram measurementsbecause dogs were less resistant to examinations and echocardiographic parameters of FS and CI remained stable.

Echocardiographic characteristics in Fontan patients before the onset of protein-losing enteropathy or plastic bronchitis.

Science.gov (United States)

Du Bois, Florian; Stiller, Brigitte; Borth-Bruhns, Thomas; Unseld, Bettina; Kubicki, Rouven; Hoehn, René; Reineker, Katja; Grohmann, Jochen; Fleck, Thilo

2018-01-01

It was this study's objective to evaluate the echocardiographic characteristics and flow patterns in abdominal arteries of Fontan patients before the onset of protein-losing enteropathy (PLE) or plastic bronchitis (PB). In this retrospective cohort investigation, we examined 170 Fontan patients from 32 different centers who had undergone echocardiographic and Doppler ultrasound examinations between June 2006 and May 2013. Follow-up questionnaires were completed by 105 patients a median of 5.3 (1.5-8.5) years later to evaluate whether one of the complications had occurred since the examinations. A total of 91 patients never developed PLE or PB ("non-PLE/PB"); they were compared to 14 affected patients. Eight of the 14 patients had already been diagnosed with "present PLE/PB" when examined. Six "future PLE/PB" patients developed those complications later on and were identified on follow-up. The "future PLE/PB" patients presented significantly slower diastolic flow velocities in the celiac artery (0.1 (0.1-0.5) m/s vs 0.3 (0.1-1.0) m/s (P = .04) and in the superior mesenteric artery (0.0 (0.0-0.2) m/s vs 0.2 (0.0-0.6) m/s, P = .02) than the "non-PLE/PB" group. Median resistance indices in the celiac artery were significantly higher (0.9 (0.8-0.9) m/s vs 0.8 (0.6-0.9) m/s, (P = .01)) even before the onset of PLE or PB. An elevated flow resistance in the celiac artery may prevail in Fontan patients before the clinical manifestation of PLE or PB. © 2017 Wiley Periodicals, Inc.

Clinical utility of speckle-tracking echocardiography in cardiac resynchronisation therapy.

Science.gov (United States)

Khan, Sitara G; Klettas, Dimitris; Kapetanakis, Stam; Monaghan, Mark J

2016-03-01

Cardiac resynchronisation therapy (CRT) can profoundly improve outcome in selected patients with heart failure; however, response is difficult to predict and can be absent in up to one in three patients. There has been a substantial amount of interest in the echocardiographic assessment of left ventricular dyssynchrony, with the ultimate aim of reliably identifying patients who will respond to CRT. The measurement of myocardial deformation (strain) has conventionally been assessed using tissue Doppler imaging (TDI), which is limited by its angle dependence and ability to measure in a single plane. Two-dimensional speckle-tracking echocardiography is a technique that provides measurements of strain in three planes, by tracking patterns of ultrasound interference ('speckles') in the myocardial wall throughout the cardiac cycle. Since its initial use over 15 years ago, it has emerged as a tool that provides more robust, reproducible and sensitive markers of dyssynchrony than TDI. This article reviews the use of two-dimensional and three-dimensional speckle-tracking echocardiography in the assessment of dyssynchrony, including the identification of echocardiographic parameters that may hold predictive potential for the response to CRT. It also reviews the application of these techniques in guiding optimal LV lead placement pre-implant, with promising results in clinical improvement post-CRT. © 2016 The authors.

Clinical utility of speckle-tracking echocardiography in cardiac resynchronisation therapy

Directory of Open Access Journals (Sweden)

Sitara G Khan

2016-05-01

Full Text Available Cardiac resynchronisation therapy (CRT can profoundly improve outcome in selected patients with heart failure; however, response is difficult to predict and can be absent in up to one in three patients. There has been a substantial amount of interest in the echocardiographic assessment of left ventricular dyssynchrony, with the ultimate aim of reliably identifying patients who will respond to CRT. The measurement of myocardial deformation (strain has conventionally been assessed using tissue Doppler imaging (TDI, which is limited by its angle dependence and ability to measure in a single plane. Two-dimensional speckle-tracking echocardiography is a technique that provides measurements of strain in three planes, by tracking patterns of ultrasound interference (‘speckles’ in the myocardial wall throughout the cardiac cycle. Since its initial use over 15 years ago, it has emerged as a tool that provides more robust, reproducible and sensitive markers of dyssynchrony than TDI. This article reviews the use of two-dimensional and three-dimensional speckle-tracking echocardiography in the assessment of dyssynchrony, including the identification of echocardiographic parameters that may hold predictive potential for the response to CRT. It also reviews the application of these techniques in guiding optimal LV lead placement pre-implant, with promising results in clinical improvement post-CRT.

Correlation Between Body Mass Index and Echocardiographic Findings in Overweight Patients Compared to Normal-Weight Patients

Directory of Open Access Journals (Sweden)

Mohammad Salehi

2017-08-01

Full Text Available Background: Overweight is currently considered as the main risk factor for various chronic disorders, especially cardiovascular diseases. Unexpected hypertension is the first reaction of heart to overburden imposed by obesity or overweight. The purpose of the present study was to evaluate the correlation between body mass index (BMI and echocardiographic findings in overweight patients compared with normal-weight population. methods: This historical cohort study was conducted on 60 patients divided into two group of 30 based on their measured weights, group 1 with BMI of 20-25 kg/m2 as control and group 2 with 25echocardiographic findings were recorded for all samples. Results: The mean age of control (41.06 ± 12.82 years and oversights (46.84 ± 12.61 years was not significantly different (P = 0.067. Systolic blood pressure (P = 0.003 and pulse rate (P = 0.028 were significantly higher in overweight group; ejection fraction (P = 0.036, end-systolic (P < 0.001 and end-diastolic (P < 0.001 left ventricular dimensions, and left ventricular mass index (P = 0.005 were significantly higher in control group. Conclusion: Overweighting due to anatomical remodeling can cause diastolic heart failure in left ventricle. According to the relatively poor prognosis of treatment features in patients with probable risk factors of heart failure such as diabetes, hypertension and ischemic heart disease (IHD, it is recommended to consider overweight as an effective prognostic factor.

Imaging space charge regions in Sm-doped ceria using electrochemical strain microscopy

International Nuclear Information System (INIS)

Chen, Qian Nataly; Li, Jiangyu; Adler, Stuart B.

2014-01-01

Nanocrystalline ceria exhibits a total conductivity several orders of magnitude higher than microcrystalline ceria in air at high temperature. The most widely accepted theory for this enhancement (based on fitting of conductivity data to various transport and kinetic models) is that relatively immobile positively charged defects and/or impurities accumulate at the grain boundary core, leading to a counterbalancing increase in the number of mobile electrons (small polarons) within a diffuse space charge region adjacent to each grain boundary. In an effort to validate this model, we have applied electrochemical strain microscopy to image the location and relative population of mobile electrons near grain boundaries in polycrystalline Sm-doped ceria in air at 20–200 °C. Our results show the first direct (spatially resolved) evidence that such a diffuse space charge region does exist in ceria, and is localized to both grain boundaries and the gas-exposed surface

Imaging space charge regions in Sm-doped ceria using electrochemical strain microscopy

Energy Technology Data Exchange (ETDEWEB)

Chen, Qian Nataly; Li, Jiangyu, E-mail: jjli@uw.edu [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Adler, Stuart B., E-mail: stuadler@uw.edu [Department of Chemical Engineering, University of Washington, Seattle, Washington 98195 (United States)

2014-11-17

Nanocrystalline ceria exhibits a total conductivity several orders of magnitude higher than microcrystalline ceria in air at high temperature. The most widely accepted theory for this enhancement (based on fitting of conductivity data to various transport and kinetic models) is that relatively immobile positively charged defects and/or impurities accumulate at the grain boundary core, leading to a counterbalancing increase in the number of mobile electrons (small polarons) within a diffuse space charge region adjacent to each grain boundary. In an effort to validate this model, we have applied electrochemical strain microscopy to image the location and relative population of mobile electrons near grain boundaries in polycrystalline Sm-doped ceria in air at 20–200 °C. Our results show the first direct (spatially resolved) evidence that such a diffuse space charge region does exist in ceria, and is localized to both grain boundaries and the gas-exposed surface.

Predictive Performance of Echocardiographic Parameters for Cardiovascular Events Among Elderly Treated Hypertensive Patients.

Science.gov (United States)

Chowdhury, Enayet K; Jennings, Garry L R; Dewar, Elizabeth; Wing, Lindon M H; Reid, Christopher M

2016-07-01

Hypertension leads to cardiac structural and functional changes, commonly assessed by echocardiography. In this study, we assessed the predictive performance of different echocardiographic parameters including left ventricular hypertrophy (LVH) on future cardiovascular outcomes in elderly hypertensive patients without heart failure. Data from LVH substudy of the Second Australian National Blood Pressure trial were used. Echocardiograms were performed at entry into the study. Cardiovascular outcomes were identified over short term (median 4.2 years) and long term (median 10.9 years). LVH was defined using threshold values of LV mass (LVM) indexed to either body surface area (BSA) or height(2.7): >115/95g/m(2) (LVH-BSA(115/95)) or ≥49/45g/m(2.7) (LVH-ht(49/45)) in males/females, respectively, and ≥125g/m(2) (LVH-BSA(125)) or ≥51g/m(2.7) (LVH-ht(51)) for both sexes. In the 666 participants aged ≥65 years in this analysis, LVH prevalence at baseline was 33%-70% depending on definition; and after adjusting for potential risk factors, only LVH-BSA(115/95) predicted both short- and long-term cardiovascular outcomes. Participants having LVH-BSA(115/95) (69%) at baseline had twice the risk of having any first cardiovascular event over the short term (hazard ratio, 95% confidence interval: 2.00, 1.12-3.57, P = 0.02) and any fatal cardiovascular events (2.11, 1.21-3.68, P = 0.01) over the longer term. Among other echocardiographic parameters, LVM and LVM indexed to either BSA or height(2.7) predicted cardiovascular events over both short and longer term. In elderly treated hypertensive patients without heart failure, determining LVH by echocardiography is highly dependent on the methodology adopted. LVH-BSA(115/95) is a reliable predictor of future cardiovascular outcomes in the elderly. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Echocardiographic strain and mortality in Black Americans with end-stage renal disease on hemodialysis.

Science.gov (United States)

Pressman, Gregg S; Seetha Rammohan, Harish Raj; Romero-Corral, Abel; Fumo, Peter; Figueredo, Vincent M; Gorcsan, John

2015-11-15

End-stage renal disease (ESRD) presents a significant health burden and is associated with high cardiovascular morbidity and mortality. This is particularly true in African Americans who generally have higher rates of cardiovascular mortality. Outcomes in ESRD are related to extent of cardiovascular disease, but markers for outcome are not clearly established. Global longitudinal strain (GLS) has emerged as an important measure of left ventricular systolic function that is additive to traditional ejection fraction (EF). It can be measured on routine digital echocardiography and is reproducible. This study tested the hypothesis that GLS is associated with mortality in black Americans with ESRD and preserved EF. Forty-eight outpatients undergoing hemodialysis, 59.4 ± 13.3 years, with EF ≥50% were prospectively enrolled. GLS, measured by an offline speckle tracking algorithm, ranged from -8.6% to -22.0% with a mean of -13.4%, substantially below normal (-16% or more negative). The prevalence of left ventricular systolic dysfunction, as determined by GLS, was 89%. Patients were followed for an average of 1.9 years; all-cause mortality was 19% (9 deaths). GLS was significantly associated with mortality (hazard ratio 1.15, 95% confidence interval 1.02 to 1.30, p = 0.02), whereas EF was not. After adjustment for multiple potential confounders (age, gender, race, smoking, hypertension, diabetes, hyperlipidemia, coronary disease, heart failure, and EF), GLS remained strongly associated with mortality (hazard ratio 1.30, 95% confidence interval 1.10 to 1.56, p = 0.002). In conclusion, GLS is an important index in patients with ESRD, which is additive to EF as a marker for mortality in this high-risk group. Copyright © 2015 Elsevier Inc. All rights reserved.

Choosing Between MRI and CT Imaging in the Adult with Congenital Heart Disease.

Science.gov (United States)

Bonnichsen, Crystal; Ammash, Naser

2016-05-01

Improvements in the outcomes of surgical and catheter-based interventions and medical therapy have led to a growing population of adult patients with congenital heart disease. Adult patients with previously undiagnosed congenital heart disease or those previously palliated or repaired may have challenging echocardiographic examinations. Understanding the distinct anatomic and hemodynamic features of the congenital anomaly and quantifying ventricular function and valvular dysfunction plays an important role in the management of these patients. Rapid advances in imaging technology with magnetic resonance imaging (MRI) and computed tomography angiography (CTA) allow for improved visualization of complex cardiac anatomy in the evaluation of this unique patient population. Although echocardiography remains the most widely used imaging tool to evaluate congenital heart disease, alternative and, at times, complimentary imaging modalities should be considered. When caring for adults with congenital heart disease, it is important to choose the proper imaging study that can answer the clinical question with the highest quality images, lowest risk to the patient, and in a cost-efficient manner.

Characterization of plastic strains and crystallographic properties surrounding defects in steam generator tubes by orientation imaging microscopy

International Nuclear Information System (INIS)

Lehockey, E.M.; Brennenstuhl, A.M.

2002-01-01

Orientation Imaging Microscopy (OIM) has become a valuable technique for characterizing grain boundary structure, texture, and grain size distribution, which govern material susceptibility to degenerative effects (e.g. IGSCC). Methods recently developed, by Kinectrics, have extended OIM capabilities toward mapping and quantifying residual plastic strains in materials. OIM is applied in the present work to characterize the distribution of plastic strains, that accumulate in CANDU steam generator tubing during installation and service potentially undermining the performance, reliability, and fitness-for-service of these components. Plastic strain that evolves in response to roller-expansion was characterized in simulated roll joints constructed from Alloy 600 tubing. Results underscore the effect of over-rolling in generating intense gradients with broad variations in strain that extend significant distances through the wall thickness. Of greater relevance is the orientation of these gradients in the transverse direction, relative to the tube axis and potential for the development of abnormal grain growth during post-expansion heat treatments. The magnitude and distribution of strain measured by OIM are remarkably consistent with Finite Element Analysis (FEA) predictions offering compelling evidence as to the reliability of the OIM technique. OIM offers superior resolution than can be practically achieved with FEA having particular relevance in identifying highly localized concentrations of strain surrounding metallurgical defects that can serve as precursors to stress-related degenerative effects (e.g. IGSCC). The spatial distribution of residual plastic strain was also characterized within the context of localized texture, and grain size morphology surrounding (OD) 'pits' and indentations found in ex-service Monel 400 and Alloy 800 SG tubes, respectively. An absence of strain surrounding these surface defects suggests their propensity for promoting more deleterious

Strain quantification in epitaxial thin films

International Nuclear Information System (INIS)

Cushley, M

2008-01-01

Strain arising in epitaxial thin films can be beneficial in some cases but devastating in others. By altering the lattice parameters, strain may give a thin film properties hitherto unseen in the bulk material. On the other hand, heavily strained systems are prone to develop lattice defects in order to relieve the strain, which can cause device failure or, at least, a decrease in functionality. Using convergent beam electron diffraction (CBED) and high-resolution transmission electron microscopy (HRTEM), it is possible to determine local strains within a material. By comparing the results from CBED and HRTEM experiments, it is possible to gain a complete view of a material, including the strain and any lattice defects present. As well as looking at how the two experimental techniques differ from each other, I will also look at how results from different image analysis algorithms compare. Strain in Si/SiGe samples and BST/SRO/MgO capacitor structures will be discussed.

Basic and advanced echocardiographic evaluation of myocardial dysfunction in sepsis and septic shock.

Science.gov (United States)

Vallabhajosyula, S; Pruthi, S; Shah, S; Wiley, B M; Mankad, S V; Jentzer, J C

2018-01-01

Sepsis continues to be a leading cause of mortality and morbidity in the intensive care unit. Cardiovascular dysfunction in sepsis is associated with worse short- and long-term outcomes. Sepsis-related myocardial dysfunction is noted in 20%-65% of these patients and manifests as isolated or combined left or right ventricular systolic or diastolic dysfunction. Echocardiography is the most commonly used modality for the diagnosis of sepsis-related myocardial dysfunction. With the increasing use of ultrasonography in the intensive care unit, there is a renewed interest in sepsis-related myocardial dysfunction. This review summarises the current scope of literature focused on sepsis-related myocardial dysfunction and highlights the use of basic and advanced echocardiographic techniques for the diagnosis of sepsis-related myocardial dysfunction and the management of sepsis and septic shock.

Machine-Learning Algorithms to Automate Morphological and Functional Assessments in 2D Echocardiography.

Science.gov (United States)

Narula, Sukrit; Shameer, Khader; Salem Omar, Alaa Mabrouk; Dudley, Joel T; Sengupta, Partho P

2016-11-29

Machine-learning models may aid cardiac phenotypic recognition by using features of cardiac tissue deformation. This study investigated the diagnostic value of a machine-learning framework that incorporates speckle-tracking echocardiographic data for automated discrimination of hypertrophic cardiomyopathy (HCM) from physiological hypertrophy seen in athletes (ATH). Expert-annotated speckle-tracking echocardiographic datasets obtained from 77 ATH and 62 HCM patients were used for developing an automated system. An ensemble machine-learning model with 3 different machine-learning algorithms (support vector machines, random forests, and artificial neural networks) was developed and a majority voting method was used for conclusive predictions with further K-fold cross-validation. Feature selection using an information gain (IG) algorithm revealed that volume was the best predictor for differentiating between HCM ands. ATH (IG = 0.24) followed by mid-left ventricular segmental (IG = 0.134) and average longitudinal strain (IG = 0.131). The ensemble machine-learning model showed increased sensitivity and specificity compared with early-to-late diastolic transmitral velocity ratio (p 13 mm. In this subgroup analysis, the automated model continued to show equal sensitivity, but increased specificity relative to early-to-late diastolic transmitral velocity ratio, e', and strain. Our results suggested that machine-learning algorithms can assist in the discrimination of physiological versus pathological patterns of hypertrophic remodeling. This effort represents a step toward the development of a real-time, machine-learning-based system for automated interpretation of echocardiographic images, which may help novice readers with limited experience. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Fatigue strain mapping via digital image correlation for Ni-based superalloys: The role of thermal activation on cube slip

International Nuclear Information System (INIS)

Mello, Alberto W.; Nicolas, Andrea; Sangid, Michael D.

2017-01-01

A deformation mechanism map for a Ni-based superalloy is presented during cyclic loading at low (300 °C), intermediate (550 °C), and high (700 °C) temperatures for low (0.7%) and high (1.0%) applied strain amplitudes. Strain mapping is performed via digital image correlation (DIC) during interrupted fatigue experiments at elevated temperatures at 1, 10, 100 and 1000 cycles, for each specified loading and temperature condition. The DIC measurements are performed in a scanning electron microscope, which allows high-resolution measurements of heterogeneous slip events and a vacuum environment to ensure stability of the speckle pattern for DIC at high temperatures. The cumulative fatigue experiments show that the slip bands are present in the first cycle and intensify with number of cycles; resulting in highly localized strain accumulation. The strain mapping results are combined with microstructure characterization via electron backscatter diffraction. The combination of crystal orientations and high-resolution strain measurements was used to determine the active slip planes. At low temperatures, slip bands follow the {111} octahedral planes. However, as temperature increases, both the {111} octahedral and {100} cubic slip planes accommodate strain. The activation of cubic slip via cross-slip within the ordered intermetallic γ’ phase has been well documented in Ni-based superalloys and is generally accepted as the mechanism responsible for the anomalous yield phenomenon. The results in this paper represent an important quantifiable study of cubic slip system activity at the mesoscale in polycrystalline γ-γ’ Ni-based superalloys, which is a key advancement to calibrate the thermal activation components of polycrystalline deformation models.

Fatigue strain mapping via digital image correlation for Ni-based superalloys: The role of thermal activation on cube slip

Energy Technology Data Exchange (ETDEWEB)

Mello, Alberto W.; Nicolas, Andrea; Sangid, Michael D., E-mail: msangid@purdue.edu

2017-05-17

A deformation mechanism map for a Ni-based superalloy is presented during cyclic loading at low (300 °C), intermediate (550 °C), and high (700 °C) temperatures for low (0.7%) and high (1.0%) applied strain amplitudes. Strain mapping is performed via digital image correlation (DIC) during interrupted fatigue experiments at elevated temperatures at 1, 10, 100 and 1000 cycles, for each specified loading and temperature condition. The DIC measurements are performed in a scanning electron microscope, which allows high-resolution measurements of heterogeneous slip events and a vacuum environment to ensure stability of the speckle pattern for DIC at high temperatures. The cumulative fatigue experiments show that the slip bands are present in the first cycle and intensify with number of cycles; resulting in highly localized strain accumulation. The strain mapping results are combined with microstructure characterization via electron backscatter diffraction. The combination of crystal orientations and high-resolution strain measurements was used to determine the active slip planes. At low temperatures, slip bands follow the {111} octahedral planes. However, as temperature increases, both the {111} octahedral and {100} cubic slip planes accommodate strain. The activation of cubic slip via cross-slip within the ordered intermetallic γ’ phase has been well documented in Ni-based superalloys and is generally accepted as the mechanism responsible for the anomalous yield phenomenon. The results in this paper represent an important quantifiable study of cubic slip system activity at the mesoscale in polycrystalline γ-γ’ Ni-based superalloys, which is a key advancement to calibrate the thermal activation components of polycrystalline deformation models.

In vivo study of myocardial elastography under graded ischemia conditions

Energy Technology Data Exchange (ETDEWEB)

Lee, Wei-Ning; Provost, Jean; Konofagou, Elisa E [Department of Biomedical Engineering, Columbia University, New York, NY (United States); Fujikura, Kana [Department of Radiology, Columbia University, New York, NY (United States); Wang Jie, E-mail: ek2191@columbia.edu [Department of Medicine, Columbia University, New York, NY (United States)

2011-02-21

The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

Independent Prognostic Value of Stroke Volume Index in Patients With Immunoglobulin Light Chain Amyloidosis.

Science.gov (United States)

2018-05-01

Heart involvement is the most important prognostic determinant in AL amyloidosis patients. Echocardiography is a cornerstone for the diagnosis and provides important prognostic information. We studied 754 patients with AL amyloidosis who underwent echocardiographic assessment at the Mayo Clinic, including a Doppler-derived measurement of stroke volume (SV) within 30 days of their diagnosis to explore the prognostic role of echocardiographic variables in the context of a well-established soluble cardiac biomarker staging system. Reproducibility of SV, myocardial contraction fraction, and left ventricular strain was assessed in a separate, yet comparable, study cohort of 150 patients from the Pavia Amyloidosis Center. The echocardiographic measures most predictive for overall survival were SV index <33 mL/min, myocardial contraction fraction <34%, and cardiac index <2.4 L/min/m 2 with respective hazard ratios (95% confidence intervals) of 2.95 (2.37-3.66), 2.36 (1.96-2.85), and 2.32 (1.91-2.80). For the subset that had left ventricular strain performed, the prognostic cut point was -14% (hazard ratios, 2.70; 95% confidence intervals, 1.84-3.96). Each parameter was independent of systolic blood pressure, Mayo staging system (NT-proBNP [N-terminal pro-B-type natriuretic peptide] and troponin), and ejection fraction on multivariable analysis. Simple predictive models for survival, including biomarker staging along with SV index or left ventricular strain, were generated. SV index prognostic performance was similar to left ventricular strain in predicting survival in AL amyloidosis, independently of biomarker staging. Because SV index is routinely calculated and widely available, it could serve as the preferred echocardiographic measure to predict outcomes in AL amyloidosis patients. © 2018 American Heart Association, Inc.

Investigating the value of right heart echocardiographic metrics for detection of pulmonary hypertension in patients with advanced lung disease.

Science.gov (United States)

Amsallem, Myriam; Boulate, David; Kooreman, Zoe; Zamanian, Roham T; Fadel, Guillaume; Schnittger, Ingela; Fadel, Elie; McConnell, Michael V; Dhillon, Gundeep; Mercier, Olaf; Haddad, François

2017-06-01

This study determined whether novel right heart echocardiography metrics help to detect pulmonary hypertension (PH) in patients with advanced lung disease (ALD). We reviewed echocardiography and catheterization data of 192 patients from the Stanford ALD registry and echocardiograms of 50 healthy controls. Accuracy of echocardiographic right heart metrics to detect PH was assessed using logistic regression and area under the ROC curves (AUC) analysis. Patients were divided into a derivation (n = 92) and validation cohort (n = 100). Experimental validation was assessed in a piglet model of mild PH followed longitudinally. Tricuspid regurgitation (TR) was not interpretable in 52% of patients. In the derivation cohort, right atrial maximal volume index (RAVI), ventricular end-systolic area index (RVESAI), free-wall longitudinal strain and tricuspid annular plane systolic excursion (TAPSE) differentiated patients with and without PH; 20% of patients without PH had moderate to severe RV enlargement by RVESAI. On multivariate analysis, RAVI and TAPSE were independently associated with PH (AUC = 0.77, p heart metrics abnormalities did not improve detection of PH in patients with interpretable TR (p > 0.05) and provided moderate detection value in patients without TR. Only two patients with more severe PH (mean pulmonary pressure 35 and 36 mmHg) were missed. The animal model confirmed that right heart enlargement discriminated best pigs with PH from shams. This study highlights the frequency of right heart enlargement and dysfunction in ALD irrespectively from presence of PH, therefore limiting their use for detection of PH.

Early detection of myocardial dysfunction using two-dimensional speckle tracking echocardiography in a young cat with hypertrophic cardiomyopathy

Directory of Open Access Journals (Sweden)

Ryohei Suzuki

2018-02-01

Full Text Available Case summary A 5-month-old intact female Scottish Fold cat was presented for cardiac evaluation. Careful auscultation detected a slight systolic murmur (Levine I/VI. The findings of electrocardiography, thoracic radiography, non-invasive blood pressure measurements and conventional echocardiographic studies were unremarkable. However, two-dimensional speckle tracking echocardiography revealed abnormalities in myocardial deformations, including decreased early-to-late diastolic strain rate ratios in longitudinal, radial and circumferential directions, and deteriorated segmental systolic longitudinal strain. At the follow-up examinations, the cat exhibited echocardiographic left ventricular hypertrophy and was diagnosed with hypertrophic cardiomyopathy using conventional echocardiography. Relevance and novel information This is the first report on the use of two-dimensional speckle tracking echocardiography for the early detection of myocardial dysfunction in a cat with hypertrophic cardiomyopathy; the myocardial dysfunction was detected before the development of hypertrophy. The findings from this case suggest that two-dimensional speckle tracking echocardiography can be useful for myocardial assessment when conventional echocardiographic and Doppler findings are ambiguous.

Strain expansion-reduction approach

Science.gov (United States)

Baqersad, Javad; Bharadwaj, Kedar

2018-02-01

Validating numerical models are one of the main aspects of engineering design. However, correlating million degrees of freedom of numerical models to the few degrees of freedom of test models is challenging. Reduction/expansion approaches have been traditionally used to match these degrees of freedom. However, the conventional reduction/expansion approaches are only limited to displacement, velocity or acceleration data. While in many cases only strain data are accessible (e.g. when a structure is monitored using strain-gages), the conventional approaches are not capable of expanding strain data. To bridge this gap, the current paper outlines a reduction/expansion technique to reduce/expand strain data. In the proposed approach, strain mode shapes of a structure are extracted using the finite element method or the digital image correlation technique. The strain mode shapes are used to generate a transformation matrix that can expand the limited set of measurement data. The proposed approach can be used to correlate experimental and analytical strain data. Furthermore, the proposed technique can be used to expand real-time operating data for structural health monitoring (SHM). In order to verify the accuracy of the approach, the proposed technique was used to expand the limited set of real-time operating data in a numerical model of a cantilever beam subjected to various types of excitations. The proposed technique was also applied to expand real-time operating data measured using a few strain gages mounted to an aluminum beam. It was shown that the proposed approach can effectively expand the strain data at limited locations to accurately predict the strain at locations where no sensors were placed.

Two dimensional and Doppler echocardiographic evaluation of patients presenting at Obafemi Awolowo University Teaching Hospitals Complex Ile Ife Nigeria a prospective study of 2501 subjects

Directory of Open Access Journals (Sweden)

Adebayo RA

2013-07-01

Full Text Available Rasaaq Ayodele Adebayo,1 Patience Olayinka Akinwusi,2 Michael Olabode Balogun,1 Anthony Olubunmi Akintomide,1 Victor Oladeji Adeyeye,1 Olugbenga Olusola Abiodun,1 Luqman Adeleke Bisiriyu,3 Suraj Adefabi Ogunyemi,1 Ebenezer Adekunle Ajayi,4 Olufemi Eyitayo Ajayi,1 Adebayo Tolulope Oyedeji5 1Cardiology Unit, Department of Medicine, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Osun State, 2Cardiology Unit, Department of Medicine, Osun State University, Osogbo, Osun State, 3Department of Demography and Social Statistics, Obafemi Awolowo University, Ile-Ife, Osun State, 4Cardiology Unit, Department of Medicine, Ekiti State University Teaching Hospital, Ado-Ekiti, Ekiti State, 5Cardiology Unit, Department of Medicine, LAUTECH Teaching Hospital, Osogbo, Osun State, Nigeria Background: Echocardiography remains a key noninvasive cardiac investigative tool in the management of patients, especially in a developing economy like Nigeria. In this study, we investigated the indications for transthoracic echocardiography and spectrum of cardiac disease found in patients referred to our cardiac unit for echocardiography. Methods: A prospective two-dimensional, pulsed, continuous, and color-flow Doppler echocardiographic evaluation was done using the transthoracic approach in 2501 patients over an eight-year period. Univariate data analysis was performed for mean age, gender, clinical indications, and diagnoses. Results: The subject age range was less than 12 months to 97 years (mean 52.39 years. There were 1352 (54.06% males and 1149 (45.94% females. The most common indication for echocardiography was hypertension (52.1% followed by congestive cardiac failure (13.9%. Others were for screening (6.1%, arrhythmias (5%, cerebrovascular disease (5%, chest pain (3.3%, chronic kidney disease (3.2%, congenital heart disease (2.6%, cardiomyopathy (1.8%, rheumatic heart disease (1.7%, diabetes mellitus (1.3%, thyrocardiac disease (1.2%, ischemic heart

Echocardiographic and non-gated computed tomographic findings of intrapericardial tumor and mediastinal tumor adjacent to the heart

International Nuclear Information System (INIS)

Ueda, Minoru; Yamada, Nobuyuki; Saito, Daiji; Haraoka, Shoichi; Tanetani, Setsuro.

1981-01-01

Echocardiographic and computed tomographic findings of a case of intrapericardial tumor are reported, and two other cases of mediastinal tumor are presented in a discussion of the differential diagnosis of intrapericardial from mediastinal tumors. Case report: A 7-year-old male complained of cough and dyspnea. Cardiomegaly had been pointed out at a mass X-ray examination about a month prior to the admission. Two-dimensional echocardiography revealed a massive anterior pericardial effusion and a fist-sized tumor with cystic structure. The tumor pushed the heart backward at the level of the aortic root. Non-gated computed tomography of the chest disclosed the size and location of the tumor, but failed to clarify the internal structure. The patient underwent successful removal of a tumor, 12 x 10 x 8 cm in size and 350 g in weight, originating from the left atrial wall. Histologically, the tumor was a fibrosarcomatous mesothelioma. Usually, an intrapericardial tumor is easily suspected by echocardiography by the presence of pericardial effusion, although there have been a few reports of intrapericardial tumors without pericardial effusion. Echocardiographic diagnosis of the intrapericardial tumor is difficult in such cases. Identification of the pericardium is necessary to diagnose whether a tumor is intra- or extrapericardial. This identification, however, is not always easy by echocardiography when the ultrasonic beams become tangent to the pericardium. The pericardium between the tumor and the heart could not be identified by echocardiography in our two cases of mediastinal tumor. Computed tomography is helpful in diagnosing the size and location of a mediastinal tumor. (author)

Strain distributions and their influence on electronic structures of WSe2-MoS2 laterally strained heterojunctions

Science.gov (United States)

Zhang, Chendong; Li, Ming-Yang; Tersoff, Jerry; Han, Yimo; Su, Yushan; Li, Lain-Jong; Muller, David A.; Shih, Chih-Kang

2018-02-01

Monolayer transition metal dichalcogenide heterojunctions, including vertical and lateral p-n junctions, have attracted considerable attention due to their potential applications in electronics and optoelectronics. Lattice-misfit strain in atomically abrupt lateral heterojunctions, such as WSe2-MoS2, offers a new band-engineering strategy for tailoring their electronic properties. However, this approach requires an understanding of the strain distribution and its effect on band alignment. Here, we study a WSe2-MoS2 lateral heterojunction using scanning tunnelling microscopy and image its moiré pattern to map the full two-dimensional strain tensor with high spatial resolution. Using scanning tunnelling spectroscopy, we measure both the strain and the band alignment of the WSe2-MoS2 lateral heterojunction. We find that the misfit strain induces type II to type I band alignment transformation. Scanning transmission electron microscopy reveals the dislocations at the interface that partially relieve the strain. Finally, we observe a distinctive electronic structure at the interface due to hetero-bonding.

Speckle tracking echocardiography in acute lupus myocarditis: comparison to conventional echocardiography

Directory of Open Access Journals (Sweden)

Riëtte Du Toit

2017-07-01

Full Text Available Aims: Lupus myocarditis occurs in 5–10% of patients with systemic lupus erythematosus (SLE. No single feature is diagnostic of lupus myocarditis. Speckle tracking echocardiography (STE can detect subclinical left ventricular dysfunction in SLE patients, with limited research on its utility in clinical lupus myocarditis. We report on STE in comparison to conventional echocardiography in patients with clinical lupus myocarditis. Methods and results: A retrospective study was done at a tertiary referral hospital in South Africa. SLE patients with lupus myocarditis were included and compared to healthy controls. Echocardiographic images were reanalyzed, including global longitudinal strain through STE. A poor echocardiographic outcome was defined as final left ventricular ejection fraction (LVEF <40%. 28 SLE patients fulfilled the criteria. Global longitudinal strain correlated with global (LVEF: r = −0.808; P = 0.001 and regional (wall motion score: r = 0.715; P < 0.001 function. In patients presenting with a LVEF ≥50%, global longitudinal strain (P = 0.023, wall motion score (P = 0.005 and diastolic function (P = 0.004 were significantly impaired vs controls. Following treatment, LVEF (35–47% (P = 0.023 and wall motion score (1.88–1.5 (P = 0.017 improved but not global longitudinal strain. Initial LVEF (34%; P = 0.046 and global longitudinal strain (−9.5%; P = 0.095 were lower in patients with a final LVEF <40%. Conclusions: This is the first known report on STE in a series of patients with clinical lupus myocarditis. Global longitudinal strain correlated with regional and global left ventricular function. Global longitudinal strain, wall motion score and diastolic parameters may be more sensitive markers of lupus myocarditis in patients presenting with a preserved LVEF ≥50%. A poor initial LVEF and global longitudinal strain were associated with a persistent LVEF <40%. Echocardiography is a non-invasive tool with diagnostic and

Electrocardiographic intricacies clarified by echocardiography--should the electrocardiogram be interpreted echocardiographically?

Science.gov (United States)

Ker, James

2012-07-12

During the past century the electrocardiogram (ECG) has established itself as an integral part of the cardiovascular examination. Since the first direct recordings of cardiac potentials by Waller in 1887, to the invention of the string galvanometer by Willem Einthoven in 1901, to use in the clinic by 1910, the electrocardiogram has become the most widely used clinical tool in the diagnosis of virtually every type of heart disease. Currently up to 20 million ECGs are performed annually in the United States alone. However, in this era of readily available echocardiography, an important caveat in the interpretation of the electrocardiogram has emerged: variants of intracardiac structures which might mimic disease on the ECG. In this perspective various structural variants of intracardiac structures, specifically variants of papillary muscles and subaortic muscular bands, will be shown, together with their associated electrocardiographic changes, mimicking disease. It is concluded that in this era of readily available echocardiography, the electrocardiogram should be interpreted echocardiographically in instances where intricate variations are seen on the surface electrocardiogram. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A general protocol of ultra-high resolution MR angiography to image the cerebro-vasculature in 6 different rats strains at high field.

Science.gov (United States)

Pastor, Géraldine; Jiménez-González, María; Plaza-García, Sandra; Beraza, Marta; Padro, Daniel; Ramos-Cabrer, Pedro; Reese, Torsten

2017-09-01

Differences in the cerebro-vasculature among strains as well as individual animals might explain variability in animal models and thus, a non-invasive method tailored to image cerebral vessel of interest with high signal to noise ratio is required. Experimentally, we describe a new general protocol of three-dimensional time-of-flight magnetic resonance angiography to visualize non-invasively the cerebral vasculature in 6 different rat strains. Flow compensated angiograms of Sprague Dawley, Wistar Kyoto, Lister Hooded, Long Evans, Fisher 344 and Spontaneous Hypertensive Rat strains were obtained without the use of contrast agents. At 11.7T using a repetition time of 60ms, an isotropic resolution of up to 62μm was achieved; total imaging time was 98min for a 3D data set. The visualization of the cerebral arteries was improved by removing extra-cranial vessels prior to the calculation of maximum intensity projection to obtain the angiograms. Ultimately, we demonstrate that the newly implemented method is also suitable to obtain angiograms following middle cerebral artery occlusion, despite the presence of intense vasogenic edema 24h after reperfusion. The careful selection of the excitation profile and repetition time at a higher static magnetic field allowed an increase in spatial resolution to reliably detect of the hypothalamic artery, the anterior choroidal artery as well as arterial branches of the peri-amygdoidal complex and the optical nerve in six different rat strains. MR angiography without contrast agent can be utilized to study cerebro-vascular abnormalities in various animal models. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Echocardiographic and Hemodynamic Predictors of Survival in Precapillary Pulmonary Hypertension: Seven-Year Follow-Up.

Science.gov (United States)

Grapsa, Julia; Pereira Nunes, Maria Carmo; Tan, Timothy C; Cabrita, Ines Zimbarra; Coulter, Taryn; Smith, Benjamin C F; Dawson, David; Gibbs, J Simon R; Nihoyannopoulos, Petros

2015-06-01

In this study, we looked at the prognostic value of echocardiographic and hemodynamic measures in a large cohort of patients with precapillary pulmonary hypertension before and after initiation of treatment. Data were collected prospectively in a cohort of consecutive patients with precapillary pulmonary hypertension referred between 2002 and 2011. A range of clinical and echocardiographic variables were collected and stored on a database to assess predictors of survival. Invasive hemodynamic data including pulmonary artery pressure, pulmonary vascular resistance, capillary wedge pressure, and cardiac index were also obtained at baseline in all patients. Outcome was defined as mortality because of cardiovascular-related death. The study cohort comprised 777 patients (514 women) with precapillary pulmonary hypertension. A total of 195 (25%) died. In multivariable analysis, moderate or severe tricuspid regurgitation (hazard ratio [HR], 26.537; 95% confidence interval, 11.536-61.044; P<0.001), right ventricular myocardial performance index (HR, 3.421; 95% confidence interval, 1.777-6.584; P<0.001), and the presence of pericardial effusion (HR, 1.38; 95% confidence interval, 1.023-1.862; P=0.035) were independent predictors of mortality. High pulmonary vascular resistance and right atrial pressure by invasive hemodynamic measurements were independent predictors of mortality (HR, 1.084; 95% confidence interval, 1.041-1.130, and 1.079, respectively; 95% confidence interval, 1.049-1.111; P<0.001 for both), whereas patients with a higher cardiac index had better survival overall (HR, 0.384; 95% confidence interval, 0.307-0.481; P<0.001). Right ventricular dysfunction, moderate-severe tricuspid regurgitation, low cardiac index, and raised right atrial pressure were associated with poor survival for both pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertensive disease patients. The severity of tricuspid regurgitation, myocardial performance index

Influence of Angiotensin-Converting-Enzyme Gene Polymorphism on Echocardiographic Data of Patients with Ischemic Heart Failure.

Science.gov (United States)

Duque, Gustavo Salgado; Silva, Dayse Aparecida da; Albuquerque, Felipe Neves de; Schneider, Roberta Siuffo; Gimenez, Alinne; Pozzan, Roberto; Rocha, Ricardo Mourilhe; Albuquerque, Denilson Campos de

2016-11-01

Association between angiotensin-converting-enzyme (ACE) gene polymorphisms and different clinical and echocardiographic outcomes has been described in patients with heart failure (HF) and coronary artery disease. Studying the genetic profile of the local population with both diseases is necessary to assess the occurrence of that association. To assess the frequency of ACE gene polymorphisms in patients with ischemic HF in a Rio de Janeiro population, as well as its association with echocardiographic findings. Genetic assessment of I/D ACE polymorphism in association with clinical, laboratory and echocardiographic analysis of 99 patients. The allele frequency was: 53 I alleles, and 145 D alleles. Genotype frequencies were: 49.5% DD; 47.48% DI; 3.02% II. Drug treatment was optimized: 98% on beta-blockers, and 84.8% on ACE inhibitors or angiotensin-receptor blocker. Echocardiographic findings: difference between left ventricular diastolic diameters (ΔLVDD) during follow-up: 2.98±8.94 (DD) vs. 0.68±8.12 (DI) vs. -11.0±7.00 (II), p=0.018; worsening during follow-up of the LV systolic diameter (LVSD): 65.3% DD vs. 19.0% DI vs. 0.0% II, p=0.01; of the LV diastolic diameter (LVDD): 65.3% DD vs. 46.8% DI vs. 0.0% II, p=0.03; and of the LV ejection fraction (LVEF): 67.3% DD vs. 40.4% DI vs. 33.3% II, p=0.024. Correlated with D allele: ΔLVEF, ΔLVSD, ΔLVDD. More DD genotype patients had worsening of the LVEF, LVSD and LVDD, followed by DI genotype patients, while II genotype patients had the best outcome. The same pattern was observed for ΔLVDD. Associação entre polimorfismos genéticos da enzima conversora da angiotensina (ECA) e diferentes evoluções clínicas e ecocardiográficas foi descrita em pacientes com insuficiência cardíaca (IC) e coronariopatia. O estudo do perfil genético da população local com as duas doenças torna-se necessário para verificar a ocorrência dessa associação. Avaliar a frequência dos polimorfismos genéticos da ECA em

Three-dimensional ultrasound strain imaging of skeletal muscles

NARCIS (Netherlands)

Gijsbertse, K.; Sprengers, A. M. J.; Nillesen, M. M.; Hansen, Hendrik H.G.; Lopata, R.G.P.; Verdonschot, N.; de Korte, C. L.

2017-01-01

In this study, a multi-dimensional strain estimation method is presented to assess local relative deformation in three orthogonal directions in 3D space of skeletal muscles during voluntary contractions. A rigid translation and compressive deformation of a block phantom, that mimics muscle

From Measurements Errors to a New Strain Gauge Design

DEFF Research Database (Denmark)

Mikkelsen, Lars Pilgaard; Zike, Sanita; Salviato, Marco

2015-01-01

Significant over-prediction of the material stiffness in the order of 1-10% for polymer based composites has been experimentally observed and numerical determined when using strain gauges for strain measurements instead of non-contact methods such as digital image correlation or less stiff method...

Subclinical Cardiac Dysfunction Detected by Strain Imaging During Breast Irradiation With Persistent Changes 6 Weeks After Treatment

Energy Technology Data Exchange (ETDEWEB)

Lo, Queenie [University of New South Wales, Sydney, NSW (Australia); Liverpool Hospital, Sydney, NSW (Australia); Hee, Leia; Batumalai, Vikneswary [University of New South Wales, Sydney, NSW (Australia); Liverpool Hospital, Sydney, NSW (Australia); Ingham Institute of Applied Medical Research, Liverpool, NSW (Australia); Allman, Christine [Liverpool Hospital, Sydney, NSW (Australia); MacDonald, Peter [University of New South Wales, Sydney, NSW (Australia); St. Vincent' s Hospital, Sydney, NSW (Australia); Delaney, Geoff P. [University of New South Wales, Sydney, NSW (Australia); Liverpool Hospital, Sydney, NSW (Australia); Ingham Institute of Applied Medical Research, Liverpool, NSW (Australia); Lonergan, Denise [Liverpool Hospital, Sydney, NSW (Australia); Ingham Institute of Applied Medical Research, Liverpool, NSW (Australia); Thomas, Liza, E-mail: l.thomas@unsw.edu.au [University of New South Wales, Sydney, NSW (Australia); Liverpool Hospital, Sydney, NSW (Australia)

2015-06-01

Purpose: To evaluate 2-dimensional strain imaging (SI) for the detection of subclinical myocardial dysfunction during and after radiation therapy (RT). Methods and Materials: Forty women with left-sided breast cancer, undergoing only adjuvant RT to the left chest, were prospectively recruited. Standard echocardiography and SI were performed at baseline, during RT, and 6 weeks after RT. Strain (S) and strain rate (Sr) parameters were measured in the longitudinal, circumferential, and radial planes. Correlation of change in global longitudinal strain (GLS % and Δ change) and the volume of heart receiving 30 Gy (V30) and mean heart dose (MHD) were examined. Results: Left ventricular ejection fraction was unchanged; however, longitudinal systolic S and Sr and radial S were significantly reduced during RT and remained reduced at 6 weeks after treatment [longitudinal S (%) −20.44 ± 2.66 baseline vs −18.60 ± 2.70* during RT vs −18.34 ± 2.86* at 6 weeks after RT; longitudinal Sr (s{sup −1}) −1.19 ± 0.21 vs −1.06 ± 0.18* vs −1.06 ± 0.16*; radial S (%) 56.66 ± 18.57 vs 46.93 ± 14.56* vs 49.22 ± 15.81*; *P<.05 vs baseline]. Diastolic Sr were only reduced 6 weeks after RT [longitudinal E Sr (s{sup −1}) 1.47 ± 0.32 vs 1.29 ± 0.27*; longitudinal A Sr (s{sup −1}) 1.19 ± 0.31 vs 1.03 ± 0.24*; *P<.05 vs baseline], whereas circumferential strain was preserved throughout. A modest correlation between S and Sr and V30 and MHD was observed (GLS Δ change and V30 ρ = 0.314, P=.05; GLS % change and V30 ρ = 0.288, P=.076; GLS Δ change and MHD ρ = 0.348, P=.03; GLS % change and MHD ρ = 0.346, P=.031). Conclusions: Subclinical myocardial dysfunction was detected by 2-dimensional SI during RT, with changes persisting 6 weeks after treatment, though long-term effects remain unknown. Additionally, a modest correlation between strain reduction and radiation dose was observed.

Intramyocardial strain estimation from cardiac cine MRI.

Science.gov (United States)

Elnakib, Ahmed; Beache, Garth M; Gimel'farb, Georgy; El-Baz, Ayman

2015-08-01

Functional strain is one of the important clinical indicators for the quantification of heart performance and the early detection of cardiovascular diseases, and functional strain parameters are used to aid therapeutic decisions and follow-up evaluations after cardiac surgery. A comprehensive framework for deriving functional strain parameters at the endocardium, epicardium, and mid-wall of the left ventricle (LV) from conventional cine MRI data was developed and tested. Cine data were collected using short TR-/TE-balanced steady-state free precession acquisitions on a 1.5T Siemens Espree scanner. The LV wall borders are segmented using a level set-based deformable model guided by a stochastic force derived from a second-order Markov-Gibbs random field model that accounts for the object shape and appearance features. Then, the mid-wall of the segmented LV is determined based on estimating the centerline between the endocardium and epicardium of the LV. Finally, a geometrical Laplace-based method is proposed to track corresponding points on successive myocardial contours throughout the cardiac cycle in order to characterize the strain evolutions. The method was tested using simulated phantom images with predefined point locations of the LV wall throughout the cardiac cycle. The method was tested on 30 in vivo datasets to evaluate the feasibility of the proposed framework to index functional strain parameters. The cine MRI-based model agreed with the ground truth for functional metrics to within 0.30 % for indexing the peak systolic strain change and 0.29 % (per unit time) for indexing systolic and diastolic strain rates. The method was feasible for in vivo extraction of functional strain parameters. Strain indexes of the endocardium, mid-wall, and epicardium can be derived from routine cine images using automated techniques, thereby improving the utility of cine MRI data for characterization of myocardial function. Unlike traditional texture-based tracking, the

Role of Echocardiography in the Management and Prognosis of Atrial Fibrillation

Science.gov (United States)

Silverman, David I; Ayirala, Srilatha R; Manning, Warren J

2012-01-01

Echocardiography plays a longstanding and vital role in the management of atrial fibrillation (AF). Advances in 2D imaging, Doppler echocardiography and strain imaging have all contributed to major progress in AF treatment. Echocardiographically measured left atrial (LA) volume is a powerful predictor of maintenance of sinus rhythm following cardioversion as well as risk of thrombus formation and thromboembolism. Doppler derived parameters of atrial mechanical function including atrial ejection force provide related prognostic information. Transesophageal echocardiocardiograpy (TEE) guided cardioversion of AF allows for rapid conversion to sinus rhythm without prolonged oral anticoagulation, and TEE serves as a useful tool during catheter ablation of AF and atrial flutter. Newer measures derived from speckle tracking offer great promise in further improving the care of patients with AF. PMID:28496715

Integrated strain array for cellular mechanobiology studies

International Nuclear Information System (INIS)

Simmons, C S; Sim, J Y; Baechtold, P; Chung, C; Borghi, N; Pruitt, B L; Gonzalez, A

2011-01-01

We have developed an integrated strain array for cell culture enabling high-throughput mechano-transduction studies. Biocompatible cell culture chambers were integrated with an acrylic pneumatic compartment and microprocessor-based control system. Each element of the array consists of a deformable membrane supported by a cylindrical pillar within a well. For user-prescribed waveforms, the annular region of the deformable membrane is pulled into the well around the pillar under vacuum, causing the pillar-supported region with cultured cells to be stretched biaxially. The optically clear device and pillar-based mechanism of operation enables imaging on standard laboratory microscopes. Straightforward fabrication utilizes off-the-shelf components, soft lithography techniques in polydimethylsiloxane and laser ablation of acrylic sheets. Proof of compatibility with basic biological assays and standard imaging equipment were accomplished by straining C2C12 skeletal myoblasts on the device for 6 h. At higher strains, cells and actin stress fibers realign with a circumferential preference

Intraoperative echocardiographic imaging of coronary arteries and graft anastomoses during coronary artery bypass grafting without cardiopulmonary bypass.

Science.gov (United States)

Suematsu, Y; Takamoto, S; Ohtsuka, T

2001-12-01

No accepted approach exists for the intraoperative evaluation of the quality of coronary arteries and the technical adequacy of graft anastomoses during coronary artery bypass grafting without cardiopulmonary bypass. We assessed the accuracy of high-frequency epicardial echocardiography and power Doppler imaging in evaluating coronary arteries during coronary artery bypass grafting without cardiopulmonary bypass. To validate measurements of coronary arteries and graft anastomoses by high-frequency epicardial echocardiography and power Doppler imaging, we compared luminal diameters determined by these methods with diameters determined histologically in a study of off-pump coronary artery bypass grafting in 20 dogs. Technical errors were deliberately created in 10 grafts (stenosis group). The results of these animal validation studies showed that the maximum luminal diameters of coronary arteries and graft anastomoses measured by high-frequency epicardial echocardiography (HEE) and power Doppler imaging (PDI) correlated well with the histologic measurements: HEE = 1.027 x Histologic measurements + 0.005 (P anastomoses were examined intraoperatively by high-frequency epicardial echocardiography and power Doppler imaging, and luminal diameters determined by power Doppler imaging were compared with those determined by postoperative coronary angiography. The results demonstrated that graft anastomosis by power Doppler imaging correlated well with the angiographic measurements: PDI = 1.018 x Angiographic measurements - 0.106 (P anastomoses and can detect technical errors and inadequacies during coronary artery bypass grafting without cardiopulmonary bypass.

Assessment of regional systolic and diastolic myocardial function using tissue Doppler and strain imaging in dogs with dilated cardiomyopathy.

Science.gov (United States)

Chetboul, Valérie; Gouni, Vassiliki; Sampedrano, Carolina Carlos; Tissier, Renaud; Serres, François; Pouchelon, Jean-Louis

2007-01-01

Tissue Doppler Imaging (TDI) or strain (St) imaging could provide sensitive indices for early detection and treatment follow-up of canine dilated cardiomyopathy (DCM). Analysis of TDI and St features in dogs with overt DCM is a prerequisite before using these new criteria in prospective screenings of predisposed families or in clinical trials. Radial and longitudinal right and left myocardial motion, assessed by TDI and St variables, is altered in dogs with DCM. Case records for 26 dogs; 14 with DCM and 12 healthy controls of comparable age and weight were reviewed. A retrospective analysis was conducted of conventional echocardiography, 2-dimensional color TDI, and St imaging data. The DCM group was characterized by decreases in radial and longitudinal systolic velocity gradients of the left ventricular free wall (LVFW), radial and longitudinal absolute values of peak systolic St of the LVFW, and longitudinal systolic right ventricular (RV) velocities (all P canine DCM.

Colony Dimorphism in Bradyrhizobium Strains

Science.gov (United States)

Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

1988-01-01

Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

Quantitative analysis of left ventricular strain using cardiac computed tomography

Energy Technology Data Exchange (ETDEWEB)

Buss, Sebastian J., E-mail: sebastian.buss@med.uni-heidelberg.de [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Schulz, Felix; Mereles, Derliz [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Hosch, Waldemar [Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg (Germany); Galuschky, Christian; Schummers, Georg; Stapf, Daniel [TomTec Imaging Systems GmbH, Munich (Germany); Hofmann, Nina; Giannitsis, Evangelos; Hardt, Stefan E. [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich [Department of Diagnostic and Interventional Radiology, University of Heidelberg, 69120 Heidelberg (Germany); Katus, Hugo A.; Korosoglou, Grigorios [Department of Cardiology, University of Heidelberg, 69120 Heidelberg (Germany)

2014-03-15

Objectives: To investigate whether cardiac computed tomography (CCT) can determine left ventricular (LV) radial, circumferential and longitudinal myocardial deformation in comparison to two-dimensional echocardiography in patients with congestive heart failure. Background: Echocardiography allows for accurate assessment of strain with high temporal resolution. A reduced strain is associated with a poor prognosis in cardiomyopathies. However, strain imaging is limited in patients with poor echogenic windows, so that, in selected cases, tomographic imaging techniques may be preferable for the evaluation of myocardial deformation. Methods: Consecutive patients (n = 27) with congestive heart failure who underwent a clinically indicated ECG-gated contrast-enhanced 64-slice dual-source CCT for the evaluation of the cardiac veins prior to cardiac resynchronization therapy (CRT) were included. All patients underwent additional echocardiography. LV radial, circumferential and longitudinal strain and strain rates were analyzed in identical midventricular short axis, 4-, 2- and 3-chamber views for both modalities using the same prototype software algorithm (feature tracking). Time for analysis was assessed for both modalities. Results: Close correlations were observed for both techniques regarding global strain (r = 0.93, r = 0.87 and r = 0.84 for radial, circumferential and longitudinal strain, respectively, p < 0.001 for all). Similar trends were observed for regional radial, longitudinal and circumferential strain (r = 0.88, r = 0.84 and r = 0.94, respectively, p < 0.001 for all). The number of non-diagnostic myocardial segments was significantly higher with echocardiography than with CCT (9.6% versus 1.9%, p < 0.001). In addition, the required time for complete quantitative strain analysis was significantly shorter for CCT compared to echocardiography (877 ± 119 s per patient versus 1105 ± 258 s per patient, p < 0.001). Conclusion: Quantitative assessment of LV strain

Aortic obstruction: anatomy and echocardiography

Directory of Open Access Journals (Sweden)

Keirns Candace

2006-09-01

Full Text Available Abstract Echocardiography is a valuable non-invasive technique for identifying the site and type of aortic obstruction. Knowledge of the morphological details of each type of obstruction is the basis for correct interpretation of the diagnostic images and clinical decisions. This study was undertaken to correlate the echocardiographic images with anatomic specimens of equivalent valvular and supravalvular aortic obstruction. Specimens were part of the collection of the Department of Embryology. Fifty six patients were studied, and forty specimens with aortic obstruction were analyzed. Echocardiographic characteristics: Thirty one (55.3% patients were women and twenty five (44.7% men. Valvular aortic obstruction was found in Thirty six patients (64.3 % and supravalvular aortic obstruction in twenty (35.7%. Anatomic characteristics: Of the forty specimens examined, twenty one (52.5% had valvular aortic obstruction and nineteen (47.5% supravalvular aortic obstruction. The anatomoechocardiographic correlation clearly showed that the anatomic findings of the specimen hearts and aortas corresponded to echocardiographic images of valvular and supravalvular aortic obstruction and provided solid corroboration of echocardiographic diagnoses.

Myocardial response to a triathlon in male athletes evaluated by Doppler tissue imaging and biochemical parameters

DEFF Research Database (Denmark)

Leetmaa, T H; Dam, A; Glintborg, D

2008-01-01

(cTnT) and pro-brain natriuretic peptide (pro-BNP)] and echocardiography. Conventional echocardiography techniques and new Doppler tissue imaging (DTI) modalities were applied before and immediately after the competition. Blood samples were drawn 1 week before, immediately after and 12-24 h post...... and systolic velocities decreased, thus suggesting reversible cardiac fatigue. When using cardiac markers and echocardiographic findings, a triathlon was found to have no significant negative effects on left ventricular function or myocardial tissue in male athletes....

Effect of out-of-plane specimen movement on strain measurement using digital-image-correlation-based video measurement in 2D and 3D

DEFF Research Database (Denmark)

Poling, Joel; Desai, Niranjan; Fischer, Gregor

2018-01-01

This study determined the effect of specimen out-of-plane movement relative to the sensor, on the accuracy of strains measured made applying 2D and 3D measurement approaches employing the state-of-the-art digital-image-correlation (DIC)-based tool iMETRUM. DIC provides a convenient and inexpensive...

Echocardiographic impact of hydration status in dialysis patients.

Science.gov (United States)

Juan-García, Isabel; Puchades, María J; Sanjuán, Rafael; Torregrosa, Isidro; Solís, Miguel Á; González, Miguel; Blasco, Marisa; Martínez, Antonio; Miguel, Alfonso

2012-01-01

Cardiovascular disease is the main cause of death in Chronic Kidney Disease patients. Left ventricular hypertrophy is the most common manifestation and it is linked to arterial hypertension and overhydration. The goal of this paper is to stratify dialyzed patients according to hydration status and to make an evaluation about the possible echocardiography alterations of the different groups. A transversal study was carried out with 117 patients: 65 were on hemodialysis and 52 on peritoneal dialysis. We performed the following tests: multifrequency bioimpedance with the BCM-Body Composition Freesenius’ Monitor system, transthoracic echocardiography, and blood tests. If ECW/TBW (extracellular water vs total body water) normalization ratio for age and gender was > 2.5% SD, the patient was considered overhydrated. HD patients are significantly overhydrated before HD (67.1%) compared to DP patients (46.1%), and almost half of the overhydrated population presents arterial hypertension. However, after an HD session, a better control of the hydration status is reached (26.1%). DP patients frequently present high arterial pressure and/or are under antihypertensive treatment (DP 76.9% vs HD 49.2%). Left ventricular hypertrophy is much more common in HD overhydrated patients, eccentric LVH being more prevalent. Overhydrated patients present significantly high values of LAVI, ILVM, OH/ECW. Bioimpedance technique allows for the detection of a large number of overhydrated patients. Echocardiographic alterations in dialyzed patients show a high correlation between the hydration stage by ECW/TBW normalized ratio for age and gender and the LAVI and ILVM.

Soft tissue strain measurement using an optical method

Science.gov (United States)

Toh, Siew Lok; Tay, Cho Jui; Goh, Cho Hong James

2008-11-01

Digital image correlation (DIC) is a non-contact optical technique that allows the full-field estimation of strains on a surface under an applied deformation. In this project, the application of an optimized DIC technique is applied, which can achieve efficiency and accuracy in the measurement of two-dimensional deformation fields in soft tissue. This technique relies on matching the random patterns recorded in images to directly obtain surface displacements and to get displacement gradients from which the strain field can be determined. Digital image correlation is a well developed technique that has numerous and varied engineering applications, including the application in soft and hard tissue biomechanics. Chicken drumstick ligaments were harvested and used during the experiments. The surface of the ligament was speckled with black paint to allow for correlation to be done. Results show that the stress-strain curve exhibits a bi-linear behavior i.e. a "toe region" and a "linear elastic region". The Young's modulus obtained for the toe region is about 92 MPa and the modulus for the linear elastic region is about 230 MPa. The results are within the values for mammalian anterior cruciate ligaments of 150-300 MPa.

The Doppler echocardiographic myocardial performance index predicts left-ventricular dilation and cardiac death after myocardial infarction

DEFF Research Database (Denmark)

Møller, J E; Søndergaard, E; Poulsen, S H

2001-01-01

To investigate the value of the Doppler-derived myocardial performance index to predict early left-ventricular (LV) dilation and cardiac death after a first acute myocardial infarction (AMI), Doppler echocardiography was performed within 24 h of hospital admission, on day 5, 1 and 3 months after...... AMI in 125 consecutive patients. The index measured on day 1 correlated well with the change in end-diastolic volume index observed from day 1 to 3 months following AMI (r = 0.66, p 0.0001). One-year survival in patients with Doppler index index > or = 0......, we conclude that the Doppler echocardiographic myocardial performance index is a predictor of LV dilation and cardiac death after a first AMI....

Intraoperative device closure of perimembranous ventricular septal defects in the young children under transthoracic echocardiographic guidance; initial experience

Directory of Open Access Journals (Sweden)

Cao Hua

2011-12-01

Full Text Available Abstract Objectives This study aimed to assess the safety and feasibility of intraoperative device closure of perimembranous ventricular septal defects (VSD in young children guided by transthoracic echocardiography (TTE. Methods We enrolled 18 patients from our hospital to participate in the study from June 2011 to September 2011. A minimal inferior median incision was performed after full evaluation of the perimembranous VSD by real-time TTE, and a domestically made device was inserted to occlude the perimembranous VSD. The proper size of the device was determined by means of transthoracic echocardiographic analysis. Results Implantation was ultimately successful in 16 patients using TTE guidance. In these cases, the complete closure rate immediately following the operation and on subsequent follow-up was 100%. Symmetric devices were used in 14 patients, and asymmetric devices were used in two patients. Two patient were transformed to surgical treatment, one for significant residual shunting, and the other for unsuccessful wire penetration of the VSD. The follow-up periods were less than nine months, and only one patient had mild aortic regurgitation. There were no instances of residual shunt, noticeable aortic regurgitation, significant arrhythmia, thrombosis, or device failure. Conclusions Minimally invasive transthoracic device closure of perimembranous VSDs is safe and feasible, using a domestically made device under transthoracic echocardiographic guidance, without the need for cardiopulmonary bypass. This technique should be considered an acceptable alternative to surgery or device closure guided by transesophageal echocardiography in selected young children. However, a long-term evaluation of outcomes is necessary.

Clinical and Echocardiographic Characteristics and Cardiovascular Outcomes According to Diabetes Status in Patients With Heart Failure and Preserved Ejection Fraction

DEFF Research Database (Denmark)

Kristensen, Søren L; Mogensen, Ulrik M; Jhund, Pardeep S

2017-01-01

in Heart Failure With Preserved Ejection Fraction) according to history of diabetes mellitus. Cox regression models were used to estimate hazard ratios for cardiovascular outcomes adjusted for known predictors, including age, sex, natriuretic peptides, and comorbidity. Echocardiographic data were available...... versus 29 kg/m2), worse Minnesota Living With Heart Failure score (48 versus 40), higher median N-terminal pro-B-type natriuretic peptide concentration (403 versus 320 pg/mL; all Pdifference in left ventricular ejection fraction. Patients with diabetes...

Impact of image quality on reliability of the measurements of left ventricular systolic function and global longitudinal strain in 2D echocardiography.

Science.gov (United States)

Nagata, Yasufumi; Kado, Yuichiro; Onoue, Takeshi; Otani, Kyoko; Nakazono, Akemi; Otsuji, Yutaka; Takeuchi, Masaaki

2018-03-01

Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) play important roles in diagnosis and management of cardiac diseases. However, the issue of the accuracy and reliability of LVEF and GLS remains to be solved. Image quality is one of the most important factors affecting measurement variability. The aim of this study was to investigate whether improved image quality could reduce observer variability. Two sets of three apical images were acquired using relatively old- and new-generation ultrasound imaging systems (Vivid 7 and Vivid E95) in 308 subjects. Image quality was assessed by endocardial border delineation index (EBDI) using a 3-point scoring system. Three observers measured the LVEF and GLS, and these values and inter-observer variability were investigated. Image quality was significantly better with Vivid E95 (EBDI: 26.8 ± 5.9) than that with Vivid 7 (22.8 ± 6.3, P  image quality yielded benefits to both LVEF and GLS measurement reliability. Multivariate analysis showed that image quality was indeed an important factor of observer variability in the measurement of LVEF and GLS. The new-generation ultrasound imaging system offers improved image quality and reduces inter-observer variability in the measurement of LVEF and GLS. © 2018 The authors.

Urine albumin/creatinine ratio and echocardiographic left ventricular structure and function in hypertensive patients with electrocardiographic left ventricular hypertrophy: The LIFE Study

DEFF Research Database (Denmark)

Wachtell, K.; Palmieri, V.; Olsen, M.H.

2002-01-01

in a large hypertensive population. Methods The urine albumin/creatinine ratio (UACR) and echocardiographic measures of LV structure and function were obtained in 833 patients with stage I to III hypertension and LV hypertrophy determined by electrocardiogram (ECG) (Cornell voltage-duration or Sokolow...... geometry and high LV mass are associated with high UACR independent of age, systolic blood pressure, diabetes, and race, suggesting parallel cardiac and microvascular damage....

Temperature measurement by thermal strain imaging with diagnostic power ultrasound, with potential for thermal index determination.

Science.gov (United States)

Liang, Hai-Dong; Zhou, Li-Xia; Wells, Peter N T; Halliwell, Michael

2009-05-01

Over the years, there has been a substantial increase in acoustic exposure in diagnostic ultrasound as new imaging modalities with higher intensities and frame rates have been introduced; and more electronic components have been packed into the probe head, so that there is a tendency for it to become hotter. With respect to potential thermal effects, including those which may be hazardous occurring during ultrasound scanning, there is a correspondingly growing need for in vivo techniques to guide the operator as to the actual temperature rise occurring in the examined tissues. Therefore, an in vivo temperature estimator would be of considerable practical value. The commonly-used method of tissue thermal index (TI) measurement with a hydrophone in water could underestimate the actual value of TI (in one report by as much as 2.9 times). To obtain meaningful results, it is necessary to map the temperature elevation in 2-D (or 3-D) space. We present methodology, results and validation of a 2-D spatial and temporal thermal strain ultrasound temperature estimation technique in phantoms, and its apparently novel application in tracking the evolution of heat deposition at diagnostic exposure levels. The same ultrasound probe is used for both transmission and reception. The displacement and thermal strain estimation methods are similar to those used in high-intensity focused ultrasound thermal monitoring. The use of radiofrequency signals permits the application of cross correlation as a similarity measurement for tracking feature displacement. The displacement is used to calculate the thermal strain directly related to the temperature rise. Good agreement was observed between the temperature rise and the ultrasound power and scan duration. Thermal strain up to 1.4% was observed during 4000-s scan. Based on the results obtained for the temperature range studied in this work, the technique demonstrates potential for applicability in phantom (and possibly in vivo tissue

Strain-induced internal fibrillation in looped aramid filaments

DEFF Research Database (Denmark)

Pauw, Brian Richard; Vigild, Martin Etchells; Mortensen, Kell

2010-01-01

in the scattering pattern is observed. One model capable of describing the intensity is a model of stacked cylinders. These cylinders could be part of the fibrillar structure present in the PPTA fibres, which consist of cylinder- to tape-like objects, the presence of which is supported by SEM images. One...... hypothetical physical interpretation presented here for the appearance of a regular internal structure is the occurrence of fibrillar separation in regions undergoing axially compressive strain, and the appearance of strain relief/slip planes between packs of fibrils in regions undergoing tensile strain...

EDITORIAL: Excelling under strain: band engineering in nanomaterials Excelling under strain: band engineering in nanomaterials

Science.gov (United States)

Demming, Anna

2013-08-01

, 'We must be clear that when it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images and establishing mental connections' [8]. Images have been central to the communication and description of the Bohr-Rutherford model described in 1913, yet the paper itself uses none, and is typical of scientific communications at the time. In fact the text itself makes an eloquent redundancy of accompanying figures but it is interesting to note in comparison with the more technologically advanced channels for current science communications that are so thankfully profuse in images and multimedia. Obviously there is now much more experimental work on systems at the nanoscale and below than a hundred years ago and this also contributes to the greater wealth of images in today's reports. The report by Nrauda and colleagues in this issue is a great example with a wide range of annotated atomic force and transmission electron microscope images, reciprocal space maps and line plots, each image speaking a thousand words and communicating the results with an immediacy that outstrips any narrative. Yet the text serves an indispensable function in relaying the insights derived from analysis of the data, suggesting growth mechanisms, driving forces and expanding the existing understanding of these systems—as Bohr might put it, adding the poetry. References [1] Bohr N 1913 On the constitution of atoms and molecules Phil. Mag 26 1 [2] Hrauda N, Zhang J J, Groiss H, Etzelstorfer T, Holý V, Bauer G, Deiter C, Seeck O H and Stangl J 2013 Strain relief and shape oscillations in site-controlled coherent SiGe islands Nanotechnology 24 335707 [3] Hall H H, Bardeen J and Pearson G L 1951 The effects of pressure and temperature on the resistance of p-n junctions in germanium Phys. Rev. 84 129-32 [4] Smith C S 1954 Piezoresistance effect in germanium and silicon Phys. Rev. 94 42-9 [5] Wei N, Xu L, Wang H-Q and Zheng

Strain distributions and their influence on electronic structures of WSe2–MoS2 laterally strained heterojunctions

KAUST Repository

Zhang, Chendong

2018-01-12

Monolayer transition metal dichalcogenide heterojunctions, including vertical and lateral p–n junctions, have attracted considerable attention due to their potential applications in electronics and optoelectronics. Lattice-misfit strain in atomically abrupt lateral heterojunctions, such as WSe2–MoS2, offers a new band-engineering strategy for tailoring their electronic properties. However, this approach requires an understanding of the strain distribution and its effect on band alignment. Here, we study a WSe2–MoS2 lateral heterojunction using scanning tunnelling microscopy and image its moiré pattern to map the full two-dimensional strain tensor with high spatial resolution. Using scanning tunnelling spectroscopy, we measure both the strain and the band alignment of the WSe2–MoS2 lateral heterojunction. We find that the misfit strain induces type II to type I band alignment transformation. Scanning transmission electron microscopy reveals the dislocations at the interface that partially relieve the strain. Finally, we observe a distinctive electronic structure at the interface due to hetero-bonding.

Strain distributions and their influence on electronic structures of WSe2–MoS2 laterally strained heterojunctions

KAUST Repository

Zhang, Chendong; Li, Ming-yang; Tersoff, Jerry; Han, Yimo; Su, Yushan; Li, Lain-Jong; Muller, David A.; Shih, Chih-Kang

2018-01-01

Monolayer transition metal dichalcogenide heterojunctions, including vertical and lateral p–n junctions, have attracted considerable attention due to their potential applications in electronics and optoelectronics. Lattice-misfit strain in atomically abrupt lateral heterojunctions, such as WSe2–MoS2, offers a new band-engineering strategy for tailoring their electronic properties. However, this approach requires an understanding of the strain distribution and its effect on band alignment. Here, we study a WSe2–MoS2 lateral heterojunction using scanning tunnelling microscopy and image its moiré pattern to map the full two-dimensional strain tensor with high spatial resolution. Using scanning tunnelling spectroscopy, we measure both the strain and the band alignment of the WSe2–MoS2 lateral heterojunction. We find that the misfit strain induces type II to type I band alignment transformation. Scanning transmission electron microscopy reveals the dislocations at the interface that partially relieve the strain. Finally, we observe a distinctive electronic structure at the interface due to hetero-bonding.

Natural history of severe atheromatous disease of the thoracic aorta: a transesophageal echocardiographic study.

Science.gov (United States)

Montgomery, D H; Ververis, J J; McGorisk, G; Frohwein, S; Martin, R P; Taylor, W R

1996-01-01

This study sought to prospectively observe the morphologic and clinical natural history of severe atherosclerotic disease of the thoracic aorta as defined by transesophageal echocardiography. Atherosclerosis of the thoracic aorta has been shown to be highly associated with risk for embolic events in transesophageal studies, but the natural history of the disease under clinical conditions has not been reported. During a 20-month period, 191 of 264 patients undergoing transesophageal echocardiography had adequate visualization of the aorta to allow atherosclerotic severity to be graded as follows: grade I = normal (44 patients); grade II = intimal thickening (52 patients); grade III = atheroma or = 5 mm (19 patients); grade V = mobile lesion (14 patients). All available patients with grades IV (8 patients) and V (10 patients) disease as well as a subgroup of 12 patients with grade III disease had follow-up transesophageal echocardiographic studies (mean [+/- SD] 11.7 +/- 0.9 months, range 6 to 22). Of 30 patients undergoing follow-up transesophageal echocardiographic studies, 20 (66%) had no change in atherosclerotic severity grade. Of the remaining 10 patients, atherosclerotic severity progressed one grade in 7 and decreased in 3 with resolved mobile lesions. Of 18 patients with grade IV or V disease of the aorta who underwent a follow-up study, 11 (61%) demonstrated formation of new mobile lesions. Of 10 patients with grade V disease on initial study who underwent follow-up study, 7 (70%) demonstrated resolution of a specific previously documented mobile lesion. However, seven patients (70%) with grade V disease also demonstrated development of a new mobile lesion. Of 33 patients with grade IV or V disease, 8 (24%) died during the study period, and 1 (3%) had a clinical embolic event. The presence of severe atherosclerotic disease of the thoracic aorta as defined by transesophageal echocardiography is associated with a high mortality rate. Although the morphologic

Clinical and echocardiographic characteristics associated with the evolution of the ductus arteriosus in the neonate with birth weight lower than 1,500g

OpenAIRE

Visconti, Luiza Fortunato; Morhy, Samira Saady; Deutsch, Alice D'Agostini; Tavares, Gl?ucia Maria Penha; Wilberg, Tatiana Jardim Mussi; Rossi, Felipe de Souza

2013-01-01

ABSTRACT Objective: To identify clinical and echocardiographic parameters associated with the evolution of the ductus arteriosus in neonates with birth weight lower than 1,500g. Methods: Retrospective study of 119 neonates in which clinical parameters (Prenatal: maternal age, risk of infection and chorioamnionitis, use of corticosteroid, mode of delivery and gestational age. Perinatal: weight, Apgar score, gender and birth weight/gestational age classification; Postnatal: use of surfactant, s...

Echocardiographic predictors of early in-hospital heart failure during first ST-elevation acute myocardial infarction: does myocardial performance index and left atrial volume improve diagnosis over conventional parameters of left ventricular function?

Directory of Open Access Journals (Sweden)

Machado Cristiano V

2011-06-01

Full Text Available Abstract Background Left ventricular ejection fraction (LVEF has been considered a major determinant of early outcome in acute myocardial infarction (AMI. Myocardial performance index (MPI has been associated to early evolution in AMI in a heterogeneous population, including non ST-elevation or previous AMI. Left atrial volume has been related with late evolution after AMI. We evaluated the independent role of clinical and echocardiographic variables including LVEF, MPI and left atrial volume in predicting early in-hospital congestive heart failure (CHF specifically in patients with a first isolated ST-elevation AMI. Methods Echocardiography was performed within 30 hours of chest pain in 95 patients with a first ST-elevation AMI followed during the first week of hospitalization. Several clinical and echocardiographic variables were analyzed. CHF was defined as Killip class ≥ II. Multivariate regression analysis was used to select independent predictor of in-hospital CHF. Results Early in-hospital CHF occurred in 29 (31% of patients. LVEF ≤ 0.45 was the single independent and highly significant predictor of early CHF among other clinical and echocardiographic variables (odds ratio 17.0; [95% CI 4.1 - 70.8]; p Conclusion For patients with first, isolated ST-elevation AMI, LVEF assessed by echocardiography still constitutes a strong and accurate independent predictor of early in-hospital CHF, superior to isolated MPI and left atrial volume in this particular subset of patients.

Echocardiographic 3D-guided 2D planimetry in quantifying left-sided valvular heart disease.

Science.gov (United States)

Argulian, Edgar; Seetharam, Karthik

2018-02-08

Echocardiographic 3D-guided 2D planimetry can improve the accuracy of valvular disease assessment. Acquisition of 3D pyramidal dataset allows subsequent multiplanar reconstruction with accurate orthogonal plane alignment to obtain the correct borders of an anatomic orifice or flow area. Studies examining the 3D-guided 2D planimetry approach in left-sided valvular heart disease were identified and reviewed. The strongest evidence exists for estimating mitral valve area in patients with rheumatic mitral valve stenosis and vena contracta area in patients with mitral regurgitation (both primary and secondary). 3D-guided approach showed excellent feasibility and reproducibility in most studies, as well as time efficiency and good correlation with reference and comparator methods. Therefore, 3D-guided 2D planimetry can be used as an important clinical tool in quantifying left-sided valvular heart disease, especially mitral valve disorders. © 2018 Wiley Periodicals, Inc.

High-tension electrical injury to the heart as assessed by radionuclide imaging

Energy Technology Data Exchange (ETDEWEB)

Iino, Hitoshi; Chikamori, Taishiro; Hatano, Tsuguhisa [Tokyo Medical Coll. (Japan)] [and others

2002-12-01

The purpose of this study was to evaluate cardiac complications associated with electrical injury, 7 patients with high-tension electrical injury (6,600 V alternating current) underwent {sup 201}Tl and {sup 123}I-metaiodobenzylguanidine (MIBG) imaging in addition to conventional electrocardiographic and echocardiographic assessments. Electrocardiography showed transient atrial fibrillation, second degree atrioventricular block, ST-segment depression, and sinus bradycardia in each patient. Echocardiography showed mild hypokinesis of the anterior wall in only 2 patients, but {sup 201}Tl and {sup 123}I-MIBG myocardial scintigraphy showed an abnormal scan image in 6/7 and 5/6 patients, respectively. Decreased radionuclide accumulation was seen primarily in areas extending from the anterior wall to the septum. Decreased radionuclide accumulation was smaller in extent and milder in degree in {sup 123}I-MIBG than in {sup 201}Tl imaging. These results suggest that even in patients without definite evidence of severe cardiac complications in conventional examinations, radionuclide imaging detects significant damage due to high-tension electrical injury, in which sympathetic nerve dysfunction might be milder than myocardial cell damage. (author)

Three-dimensional mapping of mechanical activation patterns, contractile dyssynchrony and dyscoordination by two-dimensional strain echocardiography: Rationale and design of a novel software toolbox

Directory of Open Access Journals (Sweden)

Cramer Maarten J

2008-05-01

Full Text Available Abstract Background Dyssynchrony of myocardial deformation is usually described in terms of variability only (e.g. standard deviations SD's. A description in terms of the spatio-temporal distribution pattern (vector-analysis of dyssynchrony or by indices estimating its impact by expressing dyscoordination of shortening in relation to the global ventricular shortening may be preferential. Strain echocardiography by speckle tracking is a new non-invasive, albeit 2-D imaging modality to study myocardial deformation. Methods A post-processing toolbox was designed to incorporate local, speckle tracking-derived deformation data into a 36 segment 3-D model of the left ventricle. Global left ventricular shortening, standard deviations and vectors of timing of shortening were calculated. The impact of dyssynchrony was estimated by comparing the end-systolic values with either early peak values only (early shortening reserve ESR or with all peak values (virtual shortening reserve VSR, and by the internal strain fraction (ISF expressing dyscoordination as the fraction of deformation lost internally due to simultaneous shortening and stretching. These dyssynchrony parameters were compared in 8 volunteers (NL, 8 patients with Wolff-Parkinson-White syndrome (WPW, and 7 patients before (LBBB and after cardiac resynchronization therapy (CRT. Results Dyssynchrony indices merely based on variability failed to detect differences between WPW and NL and failed to demonstrate the effect of CRT. Only the 3-D vector of onset of shortening could distinguish WPW from NL, while at peak shortening and by VSR, ESR and ISF no differences were found. All tested dyssynchrony parameters yielded higher values in LBBB compared to both NL and WPW. CRT reduced the spatial divergence of shortening (both vector magnitude and direction, and improved global ventricular shortening along with reductions in ESR and dyscoordination of shortening expressed by ISF. Conclusion Incorporation

Tumor-mimicking large vegetation attached to the tricuspid valve without predisposing factors: A case report on CT and echocardiographic findings

Energy Technology Data Exchange (ETDEWEB)

Bae, Jung Min; Choe, Yeon Hyeon; Hwang, Hye Won; Kim, Jung Sun; Kim, Wook Sung; Peck, Kyong Ran; Park, Sung Ji [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2015-10-15

We report the CT and echocardiographic findings of a tumor-mimicking large vegetation attached to the tricuspid valve (TV) of a 45-year-old man without predisposing factors. Echocardiography revealed a mobile homogeneous echogenic mass attached to the TV. Cardiac CT showed a 4.5 × 2.3 cm irregular low-density mass with scant enhancement in the right ventricle. Based on clinical findings of fever, positive blood culture results for Streptococcus viridans, and pathologic confirmation of the lesion, a diagnosis of infective endocarditis and vegetation was made.

Tumor-mimicking large vegetation attached to the tricuspid valve without predisposing factors: A case report on CT and echocardiographic findings

International Nuclear Information System (INIS)

Bae, Jung Min; Choe, Yeon Hyeon; Hwang, Hye Won; Kim, Jung Sun; Kim, Wook Sung; Peck, Kyong Ran; Park, Sung Ji

2015-01-01

We report the CT and echocardiographic findings of a tumor-mimicking large vegetation attached to the tricuspid valve (TV) of a 45-year-old man without predisposing factors. Echocardiography revealed a mobile homogeneous echogenic mass attached to the TV. Cardiac CT showed a 4.5 × 2.3 cm irregular low-density mass with scant enhancement in the right ventricle. Based on clinical findings of fever, positive blood culture results for Streptococcus viridans, and pathologic confirmation of the lesion, a diagnosis of infective endocarditis and vegetation was made

Localized strain measurements of the intervertebral disc annulus during biaxial tensile testing.

Science.gov (United States)

Karakolis, Thomas; Callaghan, Jack P

2015-01-01

Both inter-lamellar and intra-lamellar failures of the annulus have been described as potential modes of disc herniation. Attempts to characterize initial lamellar failure of the annulus have involved tensile testing of small tissue samples. The purpose of this study was to evaluate a method of measuring local surface strains through image analysis of a tensile test conducted on an isolated sample of annular tissue in order to enhance future studies of intervertebral disc failure. An annulus tissue sample was biaxial strained to 10%. High-resolution images captured the tissue surface throughout testing. Three test conditions were evaluated: submerged, non-submerged and marker. Surface strains were calculated for the two non-marker conditions based on motion of virtual tracking points. Tracking algorithm parameters (grid resolution and template size) were varied to determine the effect on estimated strains. Accuracy of point tracking was assessed through a comparison of the non-marker conditions to a condition involving markers placed on tissue surface. Grid resolution had a larger effect on local strain than template size. Average local strain error ranged from 3% to 9.25% and 0.1% to 2.0%, for the non-submerged and submerged conditions, respectively. Local strain estimation has a relatively high potential for error. Submerging the tissue provided superior strain estimates.

The Value of Quality Improvement Process in the Detection and Correction of Common Errors in Echocardiographic Hemodynamic Parameters in a Busy Echocardiography Laboratory.

Science.gov (United States)

Fanari, Zaher; Choudhry, Usman I; Reddy, Vivek K; Eze-Nliam, Chete; Hammami, Sumaya; Kolm, Paul; Weintraub, William S; Marshall, Erik S

2015-12-01

Accurate assessment of cardiac structures, ventricular function, and hemodynamics is essential for any echocardiographic laboratory. Quality improvement (QI) processes described by the American Society of Echocardiography (ASE) and the Intersocietal Commission (IAC) should be instrumental in reaching this goal. All patients undergoing transthoracic echocardiogram (TTE) followed by cardiac catheterization within 24 hours at Christiana Care Health System in 2011 and 2012 were identified, with 126 and 133 cases, respectively. Hemodynamic parameters of diastolic function and pulmonary artery systolic pressure (PASP) on TTE correlated poorly with catheterization in 2011. An educational process was developed and implemented at quarterly QI meetings based on ASE and IAC recommendations to target frequently encountered errors and provide methods for improved performance. The hemodynamic parameters were then reexamined in 2012 postintervention. Following the QI process, there was significant improvement in the correlation between invasive and echocardiographic hemodynamic measurements in both systolic and diastolic function, and PASP. This reflected in significant better correlations between echo and cath LVEF [R = 0.88, ICC = 0.87 vs. R = 0.85, ICC = 0.85; P process, as recommended by ASE and IAC, can allow for identification as well as rectification of quality issues in a large regional academic medical center hospital. © 2015, Wiley Periodicals, Inc.

MYOCARDIAL DEFORMATION AND COMPLETE LEFT BUNDLE BRANCH BLOCK

Directory of Open Access Journals (Sweden)

E. N. Pavlyukova

2015-12-01

Full Text Available Tissue Doppler imaging is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular systolic and diastolic function. Over the last 10 years, myocardial deformation imaging has become possible initially with tissue Doppler , and more recently with myocardial speckle-tracking using 2D echocardiography. Unlike simple tissue velocity measurements, deformation measurements are specific for the region of interest. Strain rate or strain measurements have been used as sensitive indicators for subclinical diseases, and it is the most widely used tool to assess mechanical dyssynchrony. Left bundle branch block is a frequent, etiologically heterogeneous, clinically hostile and diagnostically challenging entity. About 2% of patients underwent cardiac stress testing show stable or intermittent left bundle branch block. Presence of left bundle branch block is associated with a lower and slower diastolic coronary flow velocity especially during hyperemia. Stress echocardiography is the best option for the diagnosis of ischemic heart disease, albeit specificity and sensitivity reduce in patients with left bundle branch block in the territory of left anterior descending artery in presence of initial septum dyskinesia.

Study of coherence strain of GP II zones in an aged aluminum composite

International Nuclear Information System (INIS)

Hernández-Rivera, J.L.; Rivera, J.J. Cruz; Koch, C.T.; Özdöl, V.B.; Martínez-Sánchez, R.

2012-01-01

Highlights: ► Precipitation sequence was changed in 2024 Al alloy. ► Image artifacts ought to the mask size and shape increased the real strain value. ► The strain distribution around experimental GP area was non uniform and more complex than reference. ► The origin of this strain distribution are related to mechanisms by which GP precipitates lose coherence. - Abstract: Strain mapping using the geometric phase analysis (GPA) technique was applied to Al–GP II (Guinier–Preston) nanoscale precipitates, using both high resolution transmission electron microscopy (HRTEM) micrographs as well as the exit wave function (EWF) obtained by focal series reconstruction. The experimental strain results were compared with strain maps obtained from an atomic model which consisted of an Al supercell containing a GP II precipitate. It was built as a reference from literature data. The experimental results demonstrate a complex strain distribution and larger fluctuations than the reference strain maps. These differences were found to be partly a consequence of image artifacts produced by the technique as well as complex microstructural events which were present at the development stage studied.

Cardiovascular evaluation in Turner syndrome: utility of MR imaging

International Nuclear Information System (INIS)

Dawson-Falk, K.; Bakker, B.; Rosenfeld, R.G.

1992-01-01

Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome. 23 refs., 2 tabs., 5 figs

Cardiovascular evaluation in Turner syndrome: utility of MR imaging

Energy Technology Data Exchange (ETDEWEB)

Dawson-Falk, K; Bakker, B; Rosenfeld, R G [Stanford Univ., CA (United States). School of Medicine

1992-08-01

Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome. 23 refs., 2 tabs., 5 figs.

Performance evaluation of methods for two-dimensional displacement and strain estimation using ultrasound radio frequency data

NARCIS (Netherlands)

Lopata, R.G.P.; Nillesen, M.M.; Hansen, H.H.G.; Gerrits, I.H.; Thijssen, J.M.; Korte, de C.L.

2009-01-01

In elastography, several methods for 2-D strain imaging have been introduced, based on both raw frequency (RF) data and speckle-tracking. Although the precision and lesion detectability of axial strain imaging in terms of elastographic signal-to-noise ratio (SNRe) and elastographic contrast-to-noise

The tissue velocity imaging and strain rate imaging in the assessment of interatrial electromechanical conduction in patients with sick sinus syndrome before and after pacemaker implantation

Directory of Open Access Journals (Sweden)

Xiaozhi Zheng

2011-05-01

Full Text Available Tissue velocity imaging (TVI and strain rate imaging (SRI were recently introduced to quantify myocardial mechanical activity in patients receiving cardiac resynchronization therapy. To clear whether atrial-demand-based (AAI (R atrial pacing can fully simulate the electromechanical conduction of physiological state and to clarify which one is more appropriate for the assessment of electromechanical activity of the heart between TVI and SRI, 30 normal subjects and 31 patients with sick sinus syndrome (SSS before and after AAI(R pacemaker implantation (PI were investigated in this study. The results showed that the time intervals (ms, P-SRa assessed by SRI (not P-Va assessed by TVI prolonged step by step from the lateral wall of the right atrium (RA, the interatrial septum (IAS and the left atrium (LA in normal subjects(5.01±0.62, 17.05±3.54 and 45.09±12.26, p<0.01. P-Va and P-SRa did not differ at the RA, IAS and LA in patients with SSS before PI (p>0.05, and they were significant longer than those of normal subjects (p<0.01. However, they shortened to normal levels in patients with SSS after PI and P-SRa showed again the trend of gradually prolonging from the RA, IAS to LA. At the same time, the peak velocities and the peak strain rates during atrial contraction also returned to normal values from lower levels. These data suggested that AAI(R atrial pacing can successfully reverse the abnormal interatrial electromechanical conduction in patients with SSS, and SRI is more appropriate for the assessment of the electromechanical activity of atrial wall than TVI.

How Does Subclinical Hyperthyroidism Affect Right Heart Function and Mechanics?

Science.gov (United States)

Tadic, Marijana; Celic, Vera; Cuspidi, Cesare; Ilic, Sanja; Zivanovic, Vladimir; Marjanovic, Tamara

2016-02-01

Right heart function and mechanics have not been investigated in patients with subclinical hyperthyroidism. Our aim was to investigate right ventricular (RV) and right atrial (RA) function and deformation as evaluated by 3-dimensional echocardiography (3DE) and speckle-tracking 2-dimensional echocardiography (2DE) in these individuals. We included 39 untreated women with endogenous subclinical hyperthyroidism and 39 healthy women matched by age. All participants underwent laboratory analyses that included thyroid hormone levels and comprehensive 2DE and 3DE examinations. Three-dimensional echocardiographic RV volumes were significantly elevated in the patients with subclinical hyperthyroidism (P < .05), whereas the 3DE RV ejection fraction was reduced in this group, but with borderline significance. Two-dimensional echocardiographic longitudinal RV and RA strain were significantly reduced in the patients with subclinical hyperthyroidism. Two-dimensional echocardiographic RV systolic and early diastolic strain rates were reduced, whereas late diastolic strain rates were increased in the patients with subclinical hyperthyroidism. The same changes were detected in RA mechanics among the patients with subclinical hyperthyroidism. The thyrotropin (TSH) level correlated with the left ventricular mass index, transmitral early diastolic peak flow velocity (E)/late diastolic flow velocity (A) ratio, tricuspid E/A ratio, 2DE RV global strain, 2DE RA, strain, and 3DE RV end-diastolic volume. A multivariate regression analysis showed that the mitral E/A ratio, 2DE RV global strain, and 3DE RV end-diastolic volume were independently associated with the TSH level. Right ventricular and RA function as evaluated by 3DE and speckle-tracking 2DE is significantly impaired in patients with subclinical hyperthyroidism. The TSH level correlated with parameters for RV function and mechanics in the whole study population. © 2016 by the American Institute of Ultrasound in Medicine.

Validation and qualification of surface-applied fibre optic strain sensors using application-independent optical techniques

International Nuclear Information System (INIS)

Schukar, Vivien G; Kadoke, Daniel; Kusche, Nadine; Münzenberger, Sven; Gründer, Klaus-Peter; Habel, Wolfgang R

2012-01-01

Surface-applied fibre optic strain sensors were investigated using a unique validation facility equipped with application-independent optical reference systems. First, different adhesives for the sensor's application were analysed regarding their material properties. Measurements resulting from conventional measurement techniques, such as thermo-mechanical analysis and dynamic mechanical analysis, were compared with measurements resulting from digital image correlation, which has the advantage of being a non-contact technique. Second, fibre optic strain sensors were applied to test specimens with the selected adhesives. Their strain-transfer mechanism was analysed in comparison with conventional strain gauges. Relative movements between the applied sensor and the test specimen were visualized easily using optical reference methods, digital image correlation and electronic speckle pattern interferometry. Conventional strain gauges showed limited opportunities for an objective strain-transfer analysis because they are also affected by application conditions. (paper)

Strain-encoding cardiovascular magnetic resonance for assessment of right-ventricular regional function

Directory of Open Access Journals (Sweden)

Abraham M Roselle

2008-07-01

Full Text Available Abstract Background Tissue tagging by cardiovascular magnetic resonance (CMR is a comprehensive method for the assessment of cardiac regional function. However, imaging the right ventricle (RV using this technique is problematic due to the thin wall of the RV relative to tag spacing which limits assessment of regional function using conventional in-plane tagging. Hypothesis We hypothesize that the use of through-plane tags in the strain-encoding (SENC CMR technique would result in reproducible measurements of the RV regional function due to the high image quality and spatial resolution possible with SENC. Aim To test the intra- and inter-observer variabilities of RV peak systolic strain measurements with SENC CMR for assessment of RV regional function (systolic strain in healthy volunteers. Methods Healthy volunteers (n = 21 were imaged using SENC. A four-chamber view was acquired in a single breath-hold. Circumferential strain was measured during systole at six equidistant points along the RV free wall. Peak contraction is defined as the maximum value of circumferential strain averaged from the six points, and regional function is defined as the strain value at each point at the time of peak contraction. Results Mean values for peak circumferential strain (± standard deviation of the basal, mid, and apical regions of the RV free wall were -20.4 ± 2.9%, -18.8 ± 3.9%, and -16.5 ± 5.7%, Altman plots showed good intra- and inter-observer agreements with mean difference of 0.11% and 0.32% and limits of agreement of -4.038 to 4.174 and -4.903 to 5.836, respectively. Conclusion SENC CMR allows for rapid quantification of RV regional function with low intra- and inter-observer variabilities, which could permit accurate quantification of regional strain in patients with RV dysfunction.

The cardiovascular profile of soccer referees: an echocardiographic study

Directory of Open Access Journals (Sweden)

Toncelli L

2008-02-01

Full Text Available Abstract Background During a soccer game, the cardiovascular system is severely taxed The referees must be alert and their level of fitness must be such that fatigue will not impair their decision-making. Referee's peak overall performance is usually after 40 when the performance starts to decline. We evaluated the morphological and functional cardiac profile of professional soccer referees. Materials and methods We submitted to a clinical and echocardiographic exam a group of 120 professional soccer referees aged 25 – 45 years, including the first division of the Italian Championship, matched with 120 soccer players, including élite soccer players. Data were compared using an unpaired Student's t test. Statistical significance was with p Results Right ventricle dimensions (22.2 ± 3.8 vs 25.9 ± 2.4 mm and Left Ventricular Mass Index (LVMi (100.5 ± 45.2 vs 105.4 ± 17.3 were significantly greater in referees than in active soccer players. Left atrium dimensions (33.7 ± 8.9 vs 36.2 ± 3.1 mm, aortic root (29.7 ± 7.9 vs 32.1 ± 3 mm and LVMi (115.1 ± 16.7 vs 134.1 ± 19.9 g/m2 were significantly greater in élite soccer players than in first-division referees. Conclusion Our investigation shows that right ventricle is greater in referees than in soccer players. The differences (left atrium, aortic root and LVMi between first division referees and élite soccer players may derive from the different training workloads.

Echocardiography derived three-dimensional printing of normal and abnormal mitral annuli

Directory of Open Access Journals (Sweden)

Feroze Mahmood

2014-01-01

Full Text Available Aims and Objectives: The objective of this study was to assess the clinical feasibility of using echocardiographic data to generate three-dimensional models of normal and pathologic mitral valve annuli before and after repair procedures. Materials and Methods: High-resolution transesophageal echocardiographic data from five patients was analyzed to delineate and track the mitral annulus (MA using Tom Tec Image-Arena software. Coordinates representing the annulus were imported into Solidworks software for constructing solid models. These solid models were converted to stereolithographic (STL file format and three-dimensionally printed by a commercially available Maker Bot Replicator 2 three-dimensional printer. Total time from image acquisition to printing was approximately 30 min. Results: Models created were highly reflective of known geometry, shape and size of normal and pathologic mitral annuli. Post-repair models also closely resembled shapes of the rings they were implanted with. Compared to echocardiographic images of annuli seen on a computer screen, physical models were able to convey clinical information more comprehensively, making them helpful in appreciating pathology, as well as post-repair changes. Conclusions: Three-dimensional printing of the MA is possible and clinically feasible using routinely obtained echocardiographic images. Given the short turn-around time and the lack of need for additional imaging, a technique we describe here has the potential for rapid integration into clinical practice to assist with surgical education, planning and decision-making.

The role of biomedical knowledge in echocardiographic interpretation expertise development: a correlation study

DEFF Research Database (Denmark)

Nielsen, Dorte Guldbrand; Gøtzsche, Ole; Eika, Berit

2010-01-01

Purpose: Little is known about factors of relevance for achieving knowledge of echocardiography (TTE); one of the essential skills defined by the European Society of Cardiology Core Curriculum. Recent research in other fields suggests that biomedical knowledge plays a more prominent role in profe......Purpose: Little is known about factors of relevance for achieving knowledge of echocardiography (TTE); one of the essential skills defined by the European Society of Cardiology Core Curriculum. Recent research in other fields suggests that biomedical knowledge plays a more prominent role...... in professional practice than previously assumed. This study investigates the role of biomedical knowledge represented by physiology knowledge in the development of echocardiographic expertise. Methods: Forty-five physicians (15 novices, 15 intermediates and 15 experts) were evaluated on echocardiography...... interpretation skills. An anatomical focused checklist was developed based on Danish Cardiology Society guidelines for a standard echocardiography of adults. A TTE case of a common and complex clinical presentation was recorded and presented to participants on a portable computer using EchoPac software...

Prognostic value of exercise echocardiography: validation of a new risk index combining echocardiographic, treadmill, and exercise electrocardiographic parameters.

Science.gov (United States)

Mazur, Wojciech; Rivera, Jose M; Khoury, Alexander F; Basu, Abhijeet G; Perez-Verdia, Alejandro; Marks, Gary F; Chang, Su Min; Olmos, Leopoldo; Quiñones, Miguel A; Zoghbi, William A

2003-04-01

Exercise (Ex) echocardiography has been shown to have significant prognostic power, independent of other known predictors of risk from an Ex stress test. The purpose of this study was to evaluate a risk index, incorporating echocardiographic and conventional Ex variables, for a more comprehensive risk stratification and identification of a very low-risk group. Two consecutive, mutually exclusive populations referred for treadmill Ex echocardiography with the Bruce protocol were investigated: hypothesis-generating (388 patients; 268 males; age 55 +/- 13 years) and hypothesis-testing (105 patients; 61 males age: 54 +/- 14 years).Cardiac events included cardiac death, myocardial infarction, late revascularization (>90 days), hospital admission for unstable angina, and admission for heart failure. Mean follow-up in the hypothesis-generating population was 3.1 years. There were 38 cardiac events. Independent predictors of events by multivariate analysis were: Ex wall motion score index (odds ratio [OR] = 2.77/Unit; P or = 1 mm (OR = 2.84; P =.002); and treadmill time (OR = 0.87/min; P =.037). A risk index was generated on the basis of the multivariate Cox regression model as: risk index = 1.02 (Ex wall motion score index) + 1.04 (S-T change) - 0.14 (treadmill time). The validity of this index was tested in the hypothesis-testing population. Event rates at 3 years were lowest (0%) in the lower quartile of risk index (-1.22 to -0.47), highest (29.6%) in the upper quartile (+0.66 to +2.02), and intermediate (19.2% to 15.3%) in the intermediate quartiles. The OR of the risk index for predicting cardiac events was 2.94/Unit ([95% confidence interval: 1.4 to 6.2]; P =.0043). Echocardiographic and Ex parameters are independent powerful predictors of cardiac events after treadmill stress testing. A risk index can be derived with these parameters for a more comprehensive risk stratification with Ex echocardiography.

From measurements errors to a new strain gauge design for composite materials

DEFF Research Database (Denmark)

Mikkelsen, Lars Pilgaard; Salviato, Marco; Gili, Jacopo

2015-01-01

Significant over-prediction of the material stiffness in the order of 1-10% for polymer based composites has been experimentally observed and numerical determined when using strain gauges for strain measurements instead of non-contact methods such as digital image correlation or less stiff method...

Characterization of the mechanical behavior and pathophysiological state of abdominal aortic aneurysms based on 4D ultrasound strain imaging

Science.gov (United States)

Wittek, Andreas; Blase, Christopher; Derwich, Wojciech; Schmitz-Rixen, Thomas; Fritzen, Claus-Peter

2017-06-01

Abdominal aortic aneurysms (AAA) are a degenerative disease of the human aortic wall that may lead to weakening and eventually rupture of the wall with high mortality rates. Since the currently established criterion for surgical or endovascular treatment of the disease is imprecise in the individual case and treatment is not free of complications, the need for additional patient-individual biomarkers for short-term AAA rupture risk as basis for improved clinical decision making. Time resolved 3D ultrasound combined with speckle tracking algorithms is a novel non-invasive medical imaging technique that provides full-field displacement and strain measurements of aortic and aneurysmal wall motion. This is patient-individual information that has not been used so far to assess wall strength and rupture risk. The current study uses simple statistical indices of the heterogeneous spatial distribution of in-plane strain components as biomarkers for the pathological state of the aortic and aneurysmal wall. The pathophysiological rationale behind this approach are the known changes in microstructural composition of the aortic wall with progression of AAA development that results in increased stiffening and heterogeneity of the walls mechanical properties and in decreased wall strength. In a comparative analysis of the aortic wall motion of young volunteers without known cardiovascular diseases, aged arteriosclerotic patients without AAA, and AAA patients, mean values of all in-plane strain components were significantly reduced, and the heterogeneity of circumferential strain was significantly increased in the AAA group compared to both other groups. The capacity of the proposed method to differentiate between wall motion of aged, arteriosclerotic patients and AAA patients is a promising step towards a new method for in vivo assessment of AAA wall strength or stratification of AAA rupture risk as basis for improved clinical decision making on surgical or endovascular

New developments in paediatric cardiac functional ultrasound imaging.

Science.gov (United States)

de Korte, Chris L; Nillesen, Maartje M; Saris, Anne E C M; Lopata, Richard G P; Thijssen, Johan M; Kapusta, Livia

2014-07-01

Ultrasound imaging can be used to estimate the morphology as well as the motion and deformation of tissues. If the interrogated tissue is actively deforming, this deformation is directly related to its function and quantification of this deformation is normally referred as 'strain imaging'. Tissue can also be deformed by applying an internal or external force and the resulting, induced deformation is a function of the mechanical tissue characteristics. In combination with the load applied, these strain maps can be used to estimate or reconstruct the mechanical properties of tissue. This technique was named 'elastography' by Ophir et al. in 1991. Elastography can be used for atherosclerotic plaque characterisation, while the contractility of the heart or skeletal muscles can be assessed with strain imaging. Rather than using the conventional video format (DICOM) image information, radio frequency (RF)-based ultrasound methods enable estimation of the deformation at higher resolution and with higher precision than commercial methods using Doppler (tissue Doppler imaging) or video image data (2D speckle tracking methods). However, the improvement in accuracy is mainly achieved when measuring strain along the ultrasound beam direction, so it has to be considered a 1D technique. Recently, this method has been extended to multiple directions and precision further improved by using spatial compounding of data acquired at multiple beam steered angles. Using similar techniques, the blood velocity and flow can be determined. RF-based techniques are also beneficial for automated segmentation of the ventricular cavities. In this paper, new developments in different techniques of quantifying cardiac function by strain imaging, automated segmentation, and methods of performing blood flow imaging are reviewed and their application in paediatric cardiology is discussed.

WE-EF-210-06: Ultrasound 2D Strain Measurement of Radiation-Induced Toxicity: Phantom and Ex Vivo Experiments

Energy Technology Data Exchange (ETDEWEB)

Liu, T; Torres, M; Rossi, P; Jani, A; Curran, W; Yang, X [Emory Univ, Atlanta, GA (United States)

2015-06-15

Purpose: Radiation-induced fibrosis is a common long-term complication affecting many patients following cancer radiotherapy. Standard clinical assessment of subcutaneous fibrosis is subjective and often limited to visual inspection and palpation. Ultrasound strain imaging describes the compressibility (elasticity) of biological tissues. This study’s purpose is to develop a quantitative ultrasound strain imaging that can consistently and accurately characterize radiation-induce fibrosis. Methods: In this study, we propose a 2D strain imaging method based on deformable image registration. A combined affine and B-spline transformation model is used to calculate the displacement of tissue between pre-stress and post-stress B-mode image sequences. The 2D displacement is estimated through a hybrid image similarity measure metric, which is a combination of the normalized mutual information (NMI) and normalized sum-of-squared-differences (NSSD). And 2D strain is obtained from the gradient of the local displacement. We conducted phantom experiments under various compressions and compared the performance of our proposed method with the standard cross-correlation (CC)- based method using the signal-to-noise (SNR) and contrast-to-noise (CNS) ratios. In addition, we conducted ex-vivo beef muscle experiment to further validate the proposed method. Results: For phantom study, the SNR and CNS values of the proposed method were significantly higher than those calculated from the CC-based method under different strains. The SNR and CNR increased by a factor of 1.9 and 2.7 comparing to the CC-based method. For the ex-vivo experiment, the CC-based method failed to work due to large deformation (6.7%), while our proposed method could accurately detect the stiffness change. Conclusion: We have developed a 2D strain imaging technique based on the deformable image registration, validated its accuracy and feasibility with phantom and ex-vivo data. This 2D ultrasound strain imaging

Detecting strain in birefringent materials using spectral polarimetry

Science.gov (United States)

Garner, Harold R. (Inventor); Ragucci, Anthony J. (Inventor); Cisar, Alan J. (Inventor); Huebschman, Michael L. (Inventor)

2010-01-01

A method, computer program product and system for analyzing multispectral images from a plurality of regions of birefringent material, such as a polymer film, using polarized light and a corresponding polar analyzer to identify differential strain in the birefringent material. For example, the birefringement material may be low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinylidene chloride, polyester, nylon, or cellophane film. Optionally, the method includes generating a real-time quantitative strain map.

[Echocardiographic indices of the right heart in patients with coronary artery disease in different age groups].

Science.gov (United States)

Gajfulin, R A; Sumin, A N; Arhipov, O G

2016-01-01

The aim of study was to examine echocardiographic indices of right heart chambers in patients with coronary artery disease in different age groups. On 678 patients aged 38-85 years, who underwent echocardiography, are including with the use of spectral tissue Doppler. Obtained 2 age groups: 1st - patients up to 60 years (n=282) and group 2nd - patients 60 years and older (n=396). In the analysis the obtained results in patients with coronary heart disease in older age groups showed an increase in right ventricular wall thickness, systolic and average pressure in the pulmonary artery. These changes were accompanied by deterioration in left ventricular diastolic function, while the systolic function of the left and right ventricle were independent of age. Thus, the results can be recommended for assessment of right ventricular dysfunction in patients of older age groups.

Comparison of three methods of calculating strain in the mouse ulna in exogenous loading studies.

Science.gov (United States)

Norman, Stephanie C; Wagner, David W; Beaupre, Gary S; Castillo, Alesha B

2015-01-02

Axial compression of mouse limbs is commonly used to induce bone formation in a controlled, non-invasive manner. Determination of peak strains caused by loading is central to interpreting results. Load-strain calibration is typically performed using uniaxial strain gauges attached to the diaphyseal, periosteal surface of a small number of sacrificed animals. Strain is measured as the limb is loaded to a range of physiological loads known to be anabolic to bone. The load-strain relationship determined by this subgroup is then extrapolated to a larger group of experimental mice. This method of strain calculation requires the challenging process of strain gauging very small bones which is subject to variability in placement of the strain gauge. We previously developed a method to estimate animal-specific periosteal strain during axial ulnar loading using an image-based computational approach that does not require strain gauges. The purpose of this study was to compare the relationship between load-induced bone formation rates and periosteal strain at ulnar midshaft using three different methods to estimate strain: (A) Nominal strain values based solely on load-strain calibration; (B) Strains calculated from load-strain calibration, but scaled for differences in mid-shaft cross-sectional geometry among animals; and (C) An alternative image-based computational method for calculating strains based on beam theory and animal-specific bone geometry. Our results show that the alternative method (C) provides comparable correlation between strain and bone formation rates in the mouse ulna relative to the strain gauge-dependent methods (A and B), while avoiding the need to use strain gauges. Published by Elsevier Ltd.

Thermal processing of strained silicon-on-insulator for atomically precise silicon device fabrication

International Nuclear Information System (INIS)

Lee, W.C.T.; Bishop, N.; Thompson, D.L.; Xue, K.; Scappucci, G.; Cederberg, J.G.; Gray, J.K.; Han, S.M.; Celler, G.K.; Carroll, M.S.; Simmons, M.Y.

2013-01-01

Highlights: ► Strained silicon-on-insulator (sSOI) samples were flash-annealed at high temperature under ultra-high vacuum conditions. ► The extend of surface strain relaxation depends on the annealing temperature with no strain relaxation observed below 1020 °C. ► A 2 × 1 reconstructed surface with low defect density can be achieved. ► The annealed sSOI surface shows enhanced step undulations due to the unique energetics caused by surface strain. - Abstract: We investigate the ability to reconstruct strained silicon-on-insulator (sSOI) substrates in ultra-high vacuum for use in atomic scale device fabrication. Characterisation of the starting sSOI substrate using μRaman shows an average tensile strain of 0.8%, with clear strain modulation in a crosshatch pattern across the surface. The surfaces were heated in ultra-high vacuum from temperatures of 900 °C to 1100 °C and subsequently imaged using scanning tunnelling microscopy (STM). The initial strain modulation on the surface is observed to promote silicon migration and the formation of crosshatched surface features whose height and pitch increases with increasing annealing temperature. STM images reveal alternating narrow straight S A steps and triangular wavy S B steps attributed to the spontaneous faceting of S B and preferential adatom attachment on S B under biaxial tensile strain. Raman spectroscopy shows that despite these high temperature anneals no strain relaxation of the substrate is observed up to temperatures of 1020 °C. Above 1100 °C, strain relaxation is evident but is confined to the surface.

Office blood pressure, ambulatory blood pressure monitoring, and echocardiographic abnormalities in women with polycystic ovary syndrome: role of obesity and androgen excess.

Science.gov (United States)

Luque-Ramírez, Manuel; Martí, David; Fernández-Durán, Elena; Alpañés, Macarena; Álvarez-Blasco, Francisco; Escobar-Morreale, Héctor F

2014-03-01

Whether or not blood pressure (BP) and heart function of women with polycystic ovary syndrome (PCOS) are altered remains unclear, albeit subtle abnormalities in the regulation of BP observed in these women might suggest a mild masculinization of their cardiovascular system. To study the influence of obesity and androgen excess on BP and echocardiographic profiles of women with the syndrome, we conducted a cross-sectional case-control study comparing office and ambulatory BP monitoring, as well as echocardiographic assessments, in 63 premenopausal women with the classic phenotype, 33 nonhyperandrogenic women with regular menses, and 25 young men. Forty-nine subjects were lean and 72 had weight excess (body mass index ≥25 kg/m(2)). Participants had no previous history of hypertension and were nonsmokers. Men showed the highest BP readings, and the lowest readings were observed in control women, whereas women with PCOS had intermediate values. Undiagnosed hypertension was more common in subjects with weight excess irrespective of sex and hyperandrogenism. Women with PCOS and weight excess showed frequencies of previously undiagnosed hypertension that were similar to those of men with weight excess and higher than those observed in nonhyperandrogenic women. Lastly, male sex, weight excess and hypertension, the latter in men as well as in women with PCOS, increased left ventricular wall thickness. In summary, our results show that patients with classic PCOS and weight excess frequently have undiagnosed BP abnormalities, leading to target organ damage.

Tissue strain rate estimator using ultrafast IQ complex data

OpenAIRE

TERNIFI , Redouane; Elkateb Hachemi , Melouka; Remenieras , Jean-Pierre

2012-01-01

International audience; Pulsatile motion of brain parenchyma results from cardiac and breathing cycles. In this study, transient motion of brain tissue was estimated using an Aixplorer® imaging system allowing an ultrafast 2D acquisition mode. The strain was computed directly from the ultrafast IQ complex data using the extended autocorrelation strain estimator (EASE), which provides great SNRs regardless of depth. The EASE first evaluates the autocorrelation function at each depth over a set...

Nuclear medicine imaging in endocarditis

International Nuclear Information System (INIS)

Ivancevic, V.; Munz, D.L.

1999-01-01

Infective endocarditis is a serious disease which requires early diagnosis and adequate therapy. Echocardiography plays a key role in diagnosis and follow-up. Subacute infective endocarditis, however, is often difficult to prove echocardiographically due to its more subtle morphological changes. Also, echocardiography cannot reliably differentiate florid vegetations from residual structural changes of the affected valves in cured patients. Therefor, scintigraphy of infection and inflammation has been investigated as a complementary tool in diagnosis and follow-up of infective endocarditis. Immunoscintigraphy with the 99m Tc labelled anti granulocyte antibody in SPECT technique is complementary to echocardiography and seems to assess the floridity of the underlying inflammatory process. The combined use of both imaging modalities allows detection of virtually all cases of subacute infective endocarditis. SPECT immunoscintigraphy with the anti granulocyte antibody seems useful in doubtful cases of infective endocarditis, especially, if echocardiography is non-diagnostic and valve pathology pre-existing. the method may be used for follow-up and monitoring antibiotic therapy

Nuclear medicine imaging in endocarditis

Energy Technology Data Exchange (ETDEWEB)

Ivancevic, V.; Munz, D.L. (Univ. Hospital Charite' , Humboldt Univ., Berlin (Germany). Clinic for Nuclear Medicine)

1999-03-01

Infective endocarditis is a serious disease which requires early diagnosis and adequate therapy. Echocardiography plays a key role in diagnosis and follow-up. Subacute infective endocarditis, however, is often difficult to prove echocardiographically due to its more subtle morphological changes. Also, echocardiography cannot reliably differentiate florid vegetations from residual structural changes of the affected valves in cured patients. Therefor, scintigraphy of infection and inflammation has been investigated as a complementary tool in diagnosis and follow-up of infective endocarditis. Immunoscintigraphy with the [sup 99m]Tc labelled anti granulocyte antibody in SPECT technique is complementary to echocardiography and seems to assess the floridity of the underlying inflammatory process. The combined use of both imaging modalities allows detection of virtually all cases of subacute infective endocarditis. SPECT immunoscintigraphy with the anti granulocyte antibody seems useful in doubtful cases of infective endocarditis, especially, if echocardiography is non-diagnostic and valve pathology pre-existing. the method may be used for follow-up and monitoring antibiotic therapy.

A new approach to ultrasonic elasticity imaging

Science.gov (United States)

Hoerig, Cameron; Ghaboussi, Jamshid; Fatemi, Mostafa; Insana, Michael F.

2016-04-01

Biomechanical properties of soft tissues can provide information regarding the local health status. Often the cells in pathological tissues can be found to form a stiff extracellular environment, which is a sensitive, early diagnostic indicator of disease. Quasi-static ultrasonic elasticity imaging provides a way to image the mechanical properties of tissues. Strain images provide a map of the relative tissue stiffness, but ambiguities and artifacts limit its diagnostic value. Accurately mapping intrinsic mechanical parameters of a region may increase diagnostic specificity. However, the inverse problem, whereby force and displacement estimates are used to estimate a constitutive matrix, is ill conditioned. Our method avoids many of the issues involved with solving the inverse problem, such as unknown boundary conditions and incomplete information about the stress field, by building an empirical model directly from measured data. Surface force and volumetric displacement data gathered during imaging are used in conjunction with the AutoProgressive method to teach artificial neural networks the stress-strain relationship of tissues. The Autoprogressive algorithm has been successfully used in many civil engineering applications and to estimate ocular pressure and corneal stiffness; here, we are expanding its use to any tissues imaged ultrasonically. We show that force-displacement data recorded with an ultrasound probe and displacements estimated at a few points in the imaged region can be used to estimate the full stress and strain vectors throughout an entire model while only assuming conservation laws. We will also demonstrate methods to parameterize the mechanical properties based on the stress-strain response of trained neural networks. This method is a fundamentally new approach to medical elasticity imaging that for the first time provides full stress and strain vectors from one set of observation data.

Longitudinal association of short-term, metronome-paced heart rate variability and echocardiographically assessed cardiac structure at a 4-year follow-up: results from the prospective, population-based CARLA cohort.

Science.gov (United States)

Medenwald, Daniel; Swenne, Cees A; Frantz, Stefan; Nuding, Sebastian; Kors, Jan A; Pietzner, Diana; Tiller, Daniel; Greiser, Karin H; Kluttig, Alexander; Haerting, Johannes

2017-12-01

To assess the value of cardiac structure/function in predicting heart rate variability (HRV) and the possibly predictive value of HRV on cardiac parameters. Baseline and 4-year follow-up data from the population-based CARLA cohort were used (790 men, 646 women, aged 45-83 years at baseline and 50-87 years at follow-up). Echocardiographic and HRV recordings were performed at baseline and at follow-up. Linear regression models with a quadratic term were used. Crude and covariate adjusted estimates were calculated. Missing values were imputed by means of multiple imputation. Heart rate variability measures taken into account consisted of linear time and frequency domain [standard deviation of normal-to-normal intervals (SDNN), high-frequency power (HF), low-frequency power (LF), LF/HF ratio] and non-linear measures [detrended fluctuation analysis (DFA1), SD1, SD2, SD1/SD2 ratio]. Echocardiographic parameters considered were ventricular mass index, diastolic interventricular septum thickness, left ventricular diastolic dimension, left atrial dimension systolic (LADS), and ejection fraction (Teichholz). A negative quadratic relation between baseline LADS and change in SDNN and HF was observed. The maximum HF and SDNN change (an increase of roughly 0.02%) was predicted at LADS of 3.72 and 3.57 cm, respectively, while the majority of subjects experienced a decrease in HRV. There was no association between further echocardiographic parameters and change in HRV, and there was no evidence of a predictive value of HRV in the prediction of changes in cardiac structure. In the general population, LADS predicts 4-year alteration in SDNN and HF non-linearly. Because of the novelty of the result, analyses should be replicated in other populations. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

A prospective echocardiographic evaluation of pulmonary hypertension in chronic hemodialysis patients in the United States: prevalence and clinical significance

Directory of Open Access Journals (Sweden)

Kumudha Ramasubbu

2010-09-01

Full Text Available Kumudha Ramasubbu1, Anita Deswal1, Cheryl Herdejurgen2, David Aguilar1, Adaani E Frost21Section of Cardiology, Michael E DeBakey VA Medical Center and Baylor College of Medicine, Houston, Texas, USA; 2Section of Pulmonary and Critical Care Medicine, Baylor College of Medicine, Houston, Texas, USABackground: Pulmonary hypertension (PH, a disease which carries substantial morbidity and mortality, has been reported to occur in 25%–45% of dialysis patients. No prospective evaluation of the prevalence or clinical significance of PH in chronic dialysis patients in the United States (US has been undertaken.Methods: Echocardiograms were performed prospectively in chronic hemodialysis patients prior to dialysis at a single dialysis center. PH was defined as a tricuspid regurgitant jet ≥2.5 m/s and “more severe PH” as ≥3.0 m/s. Clinical outcomes recovered were all-cause hospitalizations and death at 12 months.Results: In a cohort of 90 patients, 42 patients (47% met the definition of PH. Of those, 18 patients (20% met the definition of more severe PH. At 12 months, mortality was significantly higher in patients with PH (26% compared with patients without PH (6%. All-cause hospitalizations were similar in patients with PH and without PH. Echocardiographic findings suggesting impaired left ventricular function and elevated pulmonary capillary wedge pressure were significantly associated with PH.Conclusion: This prospective cross-sectional study of a single dialysis unit suggests that PH may be present in nearly half of US dialysis patients and when present is associated with increased mortality. Echocardiographic findings demonstrate an association between elevated filling pressures, elevated pulmonary artery pressures, and higher mortality, suggesting that the PH may be secondary to diastolic dysfunction and compounded by volume overload.Keywords: renal failure, pulmonary hypertension, diastolic dysfunction

Serial Echocardiographic Characteristics, Novel Biomarkers and Cachexia Development in Patients with Stable Chronic Heart Failure.

Science.gov (United States)

Gaggin, Hanna K; Belcher, Arianna M; Gandhi, Parul U; Ibrahim, Nasrien E; Januzzi, James L

2016-12-01

Little is known regarding objective predictors of cachexia affecting patients with heart failure (HF). We studied 108 stable chronic systolic HF patients with serial echocardiography and biomarker measurements over 10 months. Cachexia was defined as weight loss ≥5 % from baseline or final BMI cachexia. While there were no significant differences in baseline or serial echocardiographic measures in those developing cachexia, we found significant differences in baseline amino-terminal pro-B type natriuretic peptide (NT-proBNP), highly sensitive troponin I, sST2, and endothelin-1. Baseline log NT-proBNP (hazard ratio (HR) = 2.57, p = 0.004) and edema (HR = 3.36, p = 0.04) were predictive of cachexia in an adjusted analysis. When serial measurement of biomarkers was considered, only percent time with NT-proBNP ≥1000 pg/mL was predictive of cachexia. Thus, a close association exists between baseline and serial measurement of NT-proBNP and HF cachexia.

Invasive and noninvasive assessment of pulmonic regurgitation: clinical, angiographic, phonocardiographic, echocardiographic, and Doppler ultrasound correlations.

Science.gov (United States)

Chandraratna, P A; Wilson, D; Imaizumi, T; Ritter, W S; Aronow, W S

1982-06-01

Three patients with pulmonic regurgitation and no evidence of pulmonary hypertension were investigated. These patients had low pitched diastolic murmurs which increased on inspiration, evidence of connective tissue disease as manifested by lax joints and hyperextensible skin, and marked hilar dance which extended up to the peripheral vessels. Suprasternal echocardiography revealed dilatation and increased systolic expansion of the right pulmonary artery (RPA) (25% and 28%, respectively) in two patients; the third patient had a normal RPA dimension in diastole and a marked increase in diameter (88%) in systole. Thus, these three patients demonstrated hyperdistensibility of the RPA. The spectral signal from the pulsed doppler echocardiograph showed evidence of turbulent blood flow in diastole (wide dispersion of the dots) in the right ventricular outflow tract in all three patients. This pattern was indicative of pulmonic regurgitation. In summary, the combined use of echocardiography and Doppler ultrasound is useful in the evaluation of patients with pulmonic regurgitation.

Relationship of CHA2DS2-VASc and CHADS2 score to left atrial remodeling detected by velocity vector imaging in patients with atrial fibrillation.

Directory of Open Access Journals (Sweden)

Yihui Li

Full Text Available BACKGROUND: The CHADS2/CHA2DS2-VASc scores are used to predict thrombo-embolic/stroke in patients with nonvalvular atrial fibrillation (AF. Nevertheless, limited data are available regarding the association between these risk stratification for stroke and left atrial (LA remodeling status of AF patients. The purpose of this study was to explore the association between these scores and LA remodeling status assessed quantificationally by echocardiography in AF patients. METHODS: One hundred AF patients were divided into 3 groups based on the CHA2DS2-VASc/CHADS2 score: the score of 0 (low stroke risk, the score of 1 (moderate stroke risk and the score of ≥2 (high stroke risk. All patients were performed through conventional and velocity vector imaging echocardiography. Echocardiographic parameters: maximum LA volume index (LAVImax, LA total emptying fraction (LAEFt and LA mean strain were obtained to assess quantificationally LA remodeling status. RESULTS: On categorizing with CHA2DS2-VASc, the score of 1 group showed augment in LAVImax and attenuation in LA mean strain derived from VVI, compared with the score of 0 group (LAVImax: 40.27±21.91 vs. 26.79±7.87, p=0.002; LA mean strain: 15.18±6.36 vs. 22±8.54, p=0.001. On categorizing with the CHADS2 score, similar trends were seen between the score of ≥2 and 1 groups (LAVImax: 43.72±13.77 vs. 31.41±9.50, p<0.001; LA mean strain: 11.01±5.31 vs. 18.63±7.00, p<0.001. With multivariate logistic regression, LAVImax (odds ratio: 0.92 , 95% C=I: 0.85 to 0.98, p= 0.01 and LA mean strain reflecting LA remodeling (odds ratio: 1.10, 95% CI: 1.02 to 1.19, p=0.01 were strongly predictive of the CHA2DS2-VASc score of 0. CONCLUSIONS: The superiority of the CHADS2 score may lay in identifying LA remodeling of AF patients with high stroke risk. Whereas, the CHA2DS2-VASc score was better than the CHADS2 score at identifying LA remodeling of AF patients presenting low stroke risk.

Integrative analysis of cardiac function and metabolism in patients with idiopathic hypertrophic cardiomyopathy with H-1 cine MR imaging and P-31 MR spectroscopy

International Nuclear Information System (INIS)

Wagner, S.; Chew, W.M.; Semelka, R.; Tomei, E.; Caputo, G.; O'Sullivan, M.; Chatterjee, K.; Parmley, W.W.; Wolfe, C.L.; Higgins, C.B.

1989-01-01

The purpose of the study was to use MR imaging and P-31 spectroscopy for the functional and metabolic characterization of patients with hypertrophic cardiomyopathy (HCM). Nine patients with HCM underwent combined P-31 spectroscopy (one-dimensional chemical shift imaging) and MR imaging at 1.5 T. MR imaging localized the distribution of ventricular hypertrophy and cine MR imaging quantitated cardiac volumes, contractility, and left ventricular mass. The phosphodiester/phosphocreatine ratio (PDE/PCr) in six HCM patients was not different from normal, but in three patients it was significantly (P <.01) higher. This finding could not be attributed to contractible abnormalities, the distribution of hypertrophy, or the left ventricular mass. The abnormal PDE/PCr ratio was found only in patients with echocardiographic findings of resting left ventricular outflow obstruction but was not associated with severity or distribution of hypertrophy. The study shows the use of combined MR imaging and MR spectroscopy to characterize HCM and possibly to identify abnormal myocardial tissue

In-situ straining and time-resolved electron tomography data acquisition in a transmission electron microscope.

Science.gov (United States)

Hata, S; Miyazaki, S; Gondo, T; Kawamoto, K; Horii, N; Sato, K; Furukawa, H; Kudo, H; Miyazaki, H; Murayama, M

2017-04-01

This paper reports the preliminary results of a new in-situ three-dimensional (3D) imaging system for observing plastic deformation behavior in a transmission electron microscope (TEM) as a directly relevant development of the recently reported straining-and-tomography holder [Sato K et al. (2015) Development of a novel straining holder for transmission electron microscopy compatible with single tilt-axis electron tomography. Microsc. 64: 369-375]. We designed an integrated system using the holder and newly developed straining and image-acquisition software and then developed an experimental procedure for in-situ straining and time-resolved electron tomography (ET) data acquisition. The software for image acquisition and 3D visualization was developed based on the commercially available ET software TEMographyTM. We achieved time-resolved 3D visualization of nanometer-scale plastic deformation behavior in a Pb-Sn alloy sample, thus demonstrating the capability of this system for potential applications in materials science. © The Author 2016. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A review of techniques for visualising soft tissue microstructure deformation and quantifying strain Ex Vivo.

Science.gov (United States)

Disney, C M; Lee, P D; Hoyland, J A; Sherratt, M J; Bay, B K

2018-04-14

Many biological tissues have a complex hierarchical structure allowing them to function under demanding physiological loading conditions. Structural changes caused by ageing or disease can lead to loss of mechanical function. Therefore, it is necessary to characterise tissue structure to understand normal tissue function and the progression of disease. Ideally intact native tissues should be imaged in 3D and under physiological loading conditions. The current published in situ imaging methodologies demonstrate a compromise between imaging limitations and maintaining the samples native mechanical function. This review gives an overview of in situ imaging techniques used to visualise microstructural deformation of soft tissue, including three case studies of different tissues (tendon, intervertebral disc and artery). Some of the imaging techniques restricted analysis to observational mechanics or discrete strain measurement from invasive markers. Full-field local surface strain measurement has been achieved using digital image correlation. Volumetric strain fields have successfully been quantified from in situ X-ray microtomography (micro-CT) studies of bone using digital volume correlation but not in soft tissue due to low X-ray transmission contrast. With the latest developments in micro-CT showing in-line phase contrast capability to resolve native soft tissue microstructure, there is potential for future soft tissue mechanics research where 3D local strain can be quantified. These methods will provide information on the local 3D micromechanical environment experienced by cells in healthy, aged and diseased tissues. It is hoped that future applications of in situ imaging techniques will impact positively on the design and testing of potential tissue replacements or regenerative therapies. © 2018 The Authors Journal of Microscopy © 2018 Royal Microscopical Society.

From the Macro to the Micro: Gel Mapping to Differentiate between Sporozoites of Two Immunologically Distinct Strains of Eimeria maxima (Strains M6 and Guelph).

Science.gov (United States)

El-Ashram, Saeed; Yin, Qing; Liu, Hongbin; Al Nasr, Ibrahim; Liu, Xianyong; Suo, Xun; Barta, John

2015-01-01

Two immunologically distinct strains of E. maxima were examined in this study: the M6 strain and the Guelph strain. The differential expression between the sporozoites of the two strains of E. maxima was determined by image analysis of 100 μg of protein from each strain separated by standard one- and conventional two-dimensional polyacrylamide gel electrophoresis. In addition to differences in both molecular weight and the electrophoretic mobility, differences in the intensity of polypeptide bands for example, GS 136.4 and M6 169 were explored. Pooled gels were prepared from each strain. A representative 2D-PAGE gel spanning a non-linear pH range of 3-10 of E. maxima strain M6 consisted of approximately 694 polypeptide spots with about 67 (9.6%) of the polypeptide spots being unique relative to the other strain. E. maxima strain GS had about 696 discernable polypeptide spots with 69 spots (9.9%) that differed from those of the M6 strain. In-depth characterization of the variable polypeptide spots; unique polypeptide spots (absence or presence) and shared polypeptide spots with modifications may lead to novel vaccine target in the form of multi-component, multi-stage, multi-immunovariant strains, multi-species subunit vaccine, and diagnostic probe for E. maxima.

Splenectomized versus non-splenectomized patients with thalassemia major: Echocardiographic comparison

International Nuclear Information System (INIS)

Morsy, Mohamed-Mofeed F.; Ahmed, Ali A.; Al-Najjar, Abdulhameed A.; Almuzainy, Ibrahim S.; Alhawsawi, Zakria M.; Alserafi, Mona H.

2008-01-01

Objective was to study the effect of splenectomy in patients with thalassemia major on the cardiovascular system through echocardiographic study. A prospective, cross-sectional study was carried out from December 2006 to December 2007. Patients from the Thalassemia Center in the Maternity and Children's Hospital, Madina, Kingdom of Saudi Arabia, were screened by means of history, physical examination, laboratory studies and echocardiography. Fifty-seven patients were studied: 36 were non-splenectomized, while 21 were surgically splenectomized. The 2 study groups were well matched for age, gender, height and weight. The total amount of blood given previous year (6577+-206.9 ml versus 5390.5+-220.2 ml, p=0.0005) and the annual transfusion index (200.9+-11.3 ml versus 134.1+-7.3, p=0.0001) were significantly lower in the splenectomized group. There was no significant difference between 2 groups regarding laboratory studies. Left ventricular systolic function shows no difference regarding fraction shortening between the 2 groups. The mitral valve E/A ratio was significantly higher in the splenectomized group (1.6+-0.2 versus1.4+-0.2, p=0.02). The pulmonary artery pressure was higher in the splenectomized group (34.2+-9.1 versus 20.8+-9.2 mm Hg, p=0.0001). There was a significantly higher number of patients with pulmonary hypertension in the splenectomized group (14[66.7%] versus 6[1.7%], p=0.0004). Splenectomized patients with thalassemia major are at high risk of having impaired diastolic left ventricular function and pulmonary hypertension. (author)

Three-dimensional micro-scale strain mapping in living biological soft tissues.

Science.gov (United States)

Moo, Eng Kuan; Sibole, Scott C; Han, Sang Kuy; Herzog, Walter

2018-04-01

Non-invasive characterization of the mechanical micro-environment surrounding cells in biological tissues at multiple length scales is important for the understanding of the role of mechanics in regulating the biosynthesis and phenotype of cells. However, there is a lack of imaging methods that allow for characterization of the cell micro-environment in three-dimensional (3D) space. The aims of this study were (i) to develop a multi-photon laser microscopy protocol capable of imprinting 3D grid lines onto living tissue at a high spatial resolution, and (ii) to develop image processing software capable of analyzing the resulting microscopic images and performing high resolution 3D strain analyses. Using articular cartilage as the biological tissue of interest, we present a novel two-photon excitation imaging technique for measuring the internal 3D kinematics in intact cartilage at sub-micrometer resolution, spanning length scales from the tissue to the cell level. Using custom image processing software, we provide accurate and robust 3D micro-strain analysis that allows for detailed qualitative and quantitative assessment of the 3D tissue kinematics. This novel technique preserves tissue structural integrity post-scanning, therefore allowing for multiple strain measurements at different time points in the same specimen. The proposed technique is versatile and opens doors for experimental and theoretical investigations on the relationship between tissue deformation and cell biosynthesis. Studies of this nature may enhance our understanding of the mechanisms underlying cell mechano-transduction, and thus, adaptation and degeneration of soft connective tissues. We presented a novel two-photon excitation imaging technique for measuring the internal 3D kinematics in intact cartilage at sub-micrometer resolution, spanning from tissue length scale to cellular length scale. Using a custom image processing software (lsmgridtrack), we provide accurate and robust micro-strain

Uniaxial Compression of Cellular Materials at a 10^-1 s^-1 Strain Rate Simultaneously with Synchrotron X-ray Computed Tomographic Imaging

Energy Technology Data Exchange (ETDEWEB)

Patterson, Brian M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-03-01

The topic is presented as a series of slides. Motivation for the work included the following: X-ray tomography is a fantastic technique for characterizing a material’s starting structure as well as for non-destructive, in situ experiments to investigate material response; 3D X-ray tomography is needed to fully characterize the morphology of cellular materials; and synchrotron micro-CT can capture 3D images without pausing experiment. Among the conclusions reached are these: High-rate radiographic and tomographic imaging (0.25 s 3D frame rate) using synchrotron CT can capture full 3D images of hyper-elastic materials at a 10^-2 strain rate; dynamic true in situ uniaxial loading can be accurately captured; the three stages of compression can be imaged: bending, buckling, and breaking; implementation of linear modeling is completed; meshes have been imported into LANL modeling codes--testing and validation is underway and direct comparison and validation between in situ data and modeled mechanical response is possible.

Comparison of transcoelomic, contrast transcoelomic, and transesophageal echocardiography in anesthetized red-tailed hawks (Buteo jamaicensis).

Science.gov (United States)

Beaufrère, Hugues; Pariaut, Romain; Rodriguez, Daniel; Nevarez, Javier G; Tully, Thomas N

2012-10-01

To assess the agreement and reliability of cardiac measurements obtained with 3 echocardiographic techniques in anesthetized red-tailed hawks (Buteo jamaicensis). 10 red-tailed hawks. Transcoelomic, contrast transcoelomic, and transesophageal echocardiographic evaluations of the hawks were performed, and cineloops of imaging planes were recorded. Three observers performed echocardiographic measurements of cardiac variables 3 times on 3 days. The order in which hawks were assessed and echocardiographic techniques were used was randomized. Results were analyzed with linear mixed modeling, agreement was assessed with intraclass correlation coefficients, and variation was estimated with coefficients of variation. Significant differences were evident among the 3 echocardiographic methods for most measurements, and the agreement among findings was generally low. Interobserver agreement was generally low to medium. Intraobserver agreement was generally medium to high. Overall, better agreement was achieved for the left ventricular measurements and for the transesophageal approach than for other measurements and techniques. Echocardiographic measurements in hawks were not reliable, except when the left ventricle was measured by the same observer. Furthermore, cardiac morphometric measurements may not be clinically important. When measurements are required, one needs to consider that follow-up measurements should be performed by the same echocardiographer and should show at least a 20% difference from initial measurements to be confident that any difference is genuine.

Elliptical posts allow for detailed control of non-equibiaxial straining of cell cultures

DEFF Research Database (Denmark)

Olesen, Christian Gammelgaard; Pennisi, Cristian Pablo; de Zee, Mark

2013-01-01

tissue cells in vivo are subjected to a range of mechanical deformations including shear strain caused by activities of daily living. Shear strains are suspected to play an important role in tissue necrosis. Method The Flexcell system was redesigned using a finite element model in order to obtain large...... areas of the membrane in a controlled, uniform non-equibiaxial strain state. Results The redesign was manufactured and the resulting strains were experimentally validated by means of image analysis methods. The results showed that the system could be used for experiments varying the shear strain....... Conclusion The result allows scientists and experimentalists to apply detailed control of the strain tensor applied to tissue samples in two dimensions....

A deep learning approach to estimate chemically-treated collagenous tissue nonlinear anisotropic stress-strain responses from microscopy images.

Science.gov (United States)

Liang, Liang; Liu, Minliang; Sun, Wei

2017-11-01

Biological collagenous tissues comprised of networks of collagen fibers are suitable for a broad spectrum of medical applications owing to their attractive mechanical properties. In this study, we developed a noninvasive approach to estimate collagenous tissue elastic properties directly from microscopy images using Machine Learning (ML) techniques. Glutaraldehyde-treated bovine pericardium (GLBP) tissue, widely used in the fabrication of bioprosthetic heart valves and vascular patches, was chosen to develop a representative application. A Deep Learning model was designed and trained to process second harmonic generation (SHG) images of collagen networks in GLBP tissue samples, and directly predict the tissue elastic mechanical properties. The trained model is capable of identifying the overall tissue stiffness with a classification accuracy of 84%, and predicting the nonlinear anisotropic stress-strain curves with average regression errors of 0.021 and 0.031. Thus, this study demonstrates the feasibility and great potential of using the Deep Learning approach for fast and noninvasive assessment of collagenous tissue elastic properties from microstructural images. In this study, we developed, to our best knowledge, the first Deep Learning-based approach to estimate the elastic properties of collagenous tissues directly from noninvasive second harmonic generation images. The success of this study holds promise for the use of Machine Learning techniques to noninvasively and efficiently estimate the mechanical properties of many structure-based biological materials, and it also enables many potential applications such as serving as a quality control tool to select tissue for the manufacturing of medical devices (e.g. bioprosthetic heart valves). Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Changes in right ventricular function assessed by echocardiography in dog models of mild RV pressure overload.

Science.gov (United States)

Morita, Tomoya; Nakamura, Kensuke; Osuga, Tatsuyuki; Yokoyama, Nozomu; Morishita, Keitaro; Sasaki, Noboru; Ohta, Hiroshi; Takiguchi, Mitsuyoshi

2017-07-01

The assessment of hemodynamic change by echocardiography is clinically useful in patients with pulmonary hypertension. Recently, mild elevation of the mean pulmonary arterial pressure (PAP) has been shown to be associated with increased mortality. However, changes in the echocardiographic indices of right ventricular (RV) function are still unknown. The objective of this study was to validate the relationship between echocardiographic indices of RV function and right heart catheterization variables under a mild RV pressure overload condition. Echocardiography and right heart catheterization were performed in dog models of mild RV pressure overload induced by thromboxane A 2 analog (U46619) (n=7). The mean PAP was mildly increased (19.3±1.1 mm Hg), and the cardiac index was decreased. Most echocardiographic indices of RV function were significantly impaired even under a mild RV pressure overload condition. Multivariate analysis revealed that the RV free wall longitudinal strain (RVLS), standard deviation of the time-to-peak longitudinal strain of RV six segments (RV-SD) by speckle-tracking echocardiography, and Tei index were independent echocardiographic predictors of the mean PAP (free wall RVLS, β=-0.60, P<.001; RV-SD, β=0.40, P=.011), pulmonary vascular resistance (free wall RVLS, β=-0.39, P=.020; RV-SD, β=0.47, P=.0086; Tei index, β=0.34, P=.047), and cardiac index (Tei index, β=-0.65, P<.001). Free wall RVLS, RV-SD, and Tei index are useful for assessing the hemodynamic change under a mild RV pressure overload condition. © 2017, Wiley Periodicals, Inc.

Analysis of residual transverse stresses in a thick UD glass/polyester pultruded profile using hole drilling with strain gage and digital image correlation

Science.gov (United States)

Yuksel, Onur; Baran, Ismet; Ersoy, Nuri; Akkerman, Remko

2018-05-01

Process induced stresses inherently exist in fiber reinforced polymer composites particularly in thick parts due to the presence of non-uniform cure, shrinkage and thermal expansion/contraction during manufacturing. In order to increase the reliability and the performance of the composite materials, process models are developed to predict the residual stress formation. The accuracy of the process models is dependent on the geometrical (micro to macro), material and process parameters as well as the numerical implementation. Therefore, in order to have reliable process modelling framework, there is a need for validation and if necessary calibration of the developed models. This study focuses on measurement of the transverse residual stresses in a relatively thick pultruded profile (20×20 mm) made of glass/polyester. Process-induced residual stresses in the middle of the profile are examined with different techniques which have never been applied for transverse residual stresses in thick unidirectional composites. Hole drilling method with strain gage and digital image correlation are employed. Strain values measured from measurements are used in a finite element model (FEM) to simulate the hole drilling process and predict the residual stress level. The measured released strain is found to be approximately 180 μm/m from the strain gage. The tensile residual stress at the core of the profile is estimated approximately as 7-10 MPa. Proposed methods and measured values in this study will enable validation and calibration of the process models based on the residual stresses.

Novel method for measuring a dense 3D strain map of robotic flapping wings

Science.gov (United States)

Li, Beiwen; Zhang, Song

2018-04-01

Measuring dense 3D strain maps of the inextensible membranous flapping wings of robots is of vital importance to the field of bio-inspired engineering. Conventional high-speed 3D videography methods typically reconstruct the wing geometries through measuring sparse points with fiducial markers, and thus cannot obtain the full-field mechanics of the wings in detail. In this research, we propose a novel system to measure a dense strain map of inextensible membranous flapping wings by developing a superfast 3D imaging system and a computational framework for strain analysis. Specifically, first we developed a 5000 Hz 3D imaging system based on the digital fringe projection technique using the defocused binary patterns to precisely measure the dynamic 3D geometries of rapidly flapping wings. Then, we developed a geometry-based algorithm to perform point tracking on the precisely measured 3D surface data. Finally, we developed a dense strain computational method using the Kirchhoff-Love shell theory. Experiments demonstrate that our method can effectively perform point tracking and measure a highly dense strain map of the wings without many fiducial markers.

The Prognostic Value of Right Ventricular Deformation Imaging in Early Arrhythmogenic Right Ventricular Cardiomyopathy.

Science.gov (United States)

Mast, Thomas P; Taha, Karim; Cramer, Maarten J; Lumens, Joost; van der Heijden, Jeroen F; Bouma, Berto J; van den Berg, Maarten P; Asselbergs, Folkert W; Doevendans, Pieter A; Teske, Arco J

2018-03-09

The aim of this study was to investigate the prognostic value of echocardiographic deformation imaging in arrhythmogenic right ventricular cardiomyopathy (ARVC) to optimize family screening protocols. ARVC is characterized by variable disease expressivity among family members, which complicates family screening protocols. Previous reports have shown that echocardiographic deformation imaging detects abnormal right ventricular (RV) deformation in the absence of established disease expression in ARVC. First-degree relatives of patients with ARVC were evaluated according to 2010 task force criteria, including RV deformation imaging (n = 128). Relatives fulfilling structural task force criteria were excluded for further analysis. At baseline, deformation patterns of the subtricuspid region were scored as type I (normal deformation), type II (delayed onset, decreased systolic peak, and post-systolic shortening), or type III (systolic stretching and large post-systolic shortening). The final study population comprised relatives who underwent a second evaluation during follow-up. Disease progression was defined as the development of a new 2010 task force criterion during follow-up that was absent at baseline. Sixty-five relatives underwent a second evaluation after a mean follow-up period of 3.7 ± 2.1 years. At baseline, 28 relatives (43%) had normal deformation (type I), and 37 relatives (57%) had abnormal deformation (type II or III) in the subtricuspid region. Disease progression occurred in 4% of the relatives with normal deformation at baseline and in 43% of the relatives with abnormal deformation at baseline (p values of abnormal deformation were, respectively, 43% (95% confidence interval: 27% to 61%) and 96% (95% confidence interval: 82% to 100%). Normal RV deformation in the subtricuspid region is associated with absence of disease progression during nearly 4-year follow-up in relatives of patients with ARVC. Abnormal RV deformation seems to precede the

Evolução tardia da comissurotomia mitral em pacientes reumáticos com baixo escore ecocardiográfico Long-term evolution of mitral commissurotomy in rheumatic patients with low echocardiographic score

Directory of Open Access Journals (Sweden)

Luciano Rapold Souza

2011-09-01

Full Text Available INTRODUÇÃO: Os bons resultados da comissurotomia mitral a céu aberto são bem conhecidos e existe a hipótese de que se poderiam obter melhores resultados em pacientes selecionados pelo escore ecocardiográfico. OBJETIVO: Analisar os resultados tardios da comissurotomia mitral em pacientes selecionados pelo escore ecocardiográfico e identificar variáveis com influência nesses resultados. MÉTODOS: De janeiro de 1990 a agosto de 1994, 50 pacientes com estenose mitral reumática foram submetidos à comissurotomia mitral a céu aberto no Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Foram incluídos pacientes com idade INTRODUCTION: The good results of open mitral commissurotomy are well known and there is a hypothesis that it could provide better results in patients selected by echocardiographic score. OBJECTIVE: The purpose of this study is to analyze the late results with open mitral commissurotomy in patients selected by score and to identify variables influencing these results. METHODS: From January 1990 to August 1994, 50 patients were submitted to open mitral commissurotomy due to rheumatic mitral stenosis in Heart Institute of University of Sao Paulo Medical School. Patients with age < 60 years, in functional class II, III or IV (New York Heart Association and echocardiographic score 9 were included. The mean age was 32.7 ± 8.3 years and 41 patients (82% were female. The functional class was II in three patients (6%, III in 46 (92% and IV in one (2%. Forty six patients (92% were in sinus rhythm and four (8% were in atrial fibrillation. The mean mitral valve area was 0.9 ± 0.2 cm². RESULTS: There was no hospital mortality. There were two late deaths, one related to valve disease. Actuarial survival was 95.5 ± 3.1 %, freedom from reoperation was 62.3 ± 11,8% and freedom from tromboembolism was 88,2 ± 5,0% in 18 years. There was no endocarditis. The grade of the

Echocardiography and cardiovascular MRI entwined within the imaging domain; uniting the two. A compendium for the echocardiographer.

Science.gov (United States)

Shah, Moneal B; Doyle, Mark; Farah, Victor; Biederman, Robert W W

2018-04-01

A review of the unique and complementary roles echocardiography and cardiovascular MRI provide to the clinician. A focus on the physics of each modality as well as imaging of the left ventricle. © 2018 Wiley Periodicals, Inc.

Strain Analysis in the Assessment of a Mouse Model of Cardiotoxicity due to Chemotherapy: Sample for Preclinical Research.

Science.gov (United States)

Rea, Domenica; Coppola, Carmela; Barbieri, Antonio; Monti, Maria Gaia; Misso, Gabriella; Palma, Giuseppe; Bimonte, Sabrina; Zarone, Mayra Rachele; Luciano, Antonio; Liccardo, Davide; Maiolino, Piera; Cittadini, Antonio; Ciliberto, Gennaro; Arra, Claudio; Maurea, Nicola

2016-01-01

In recent years, the development of more effective anticancer drugs has provided great benefits in patients' quality of life by improving both prognosis and disease-free survival. Nevertheless, the frequency and severity of side-effects, with particular reference to cardiac toxicity, have gained particular attention. The purpose of this study was to create a precise and sensitive preclinical model, able to identify early contractile dysfunction in mice treated with chemotherapy, through use of speckle-tracking echocardiography. We generated a mouse model of cardiotoxicity induced by doxorubicin. C57BL 6 mice were divided into two groups, treated for 7 days by intraperitoneal injections of placebo (vehicle) or doxorubicin (2.17 mg/kg), in order to characterize the cardiac phenotype in vivo. We demonstrated that doxorubicin caused ealy remodeling of the left ventricle: after two days of therapy, the radial, circumferential and strain rates were reduced respectively by 35%, 34%, and 39% (p-value ≤0.001). Moreover, histological analysis revealed that doxorubicin treatment increased fibrosis, cardiomyocyte diameter and apoptosis. In a murine model of doxorubicin-induced cardiac injury, we detected left ventricular dysfunction followed by alterations in conventional echocardiographic indices. Our study suggests that a change in strain could be an effective early marker of myocardial dysfunction for new anticancer treatments and, in preclinical studies, it might also be a valuable indicator for the assessment of activity of cardioprotective agents. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Efficiency of B-mode Ultrasound and Strain Elastography in Differentiating Between Benign and Malignant Cervical Lymph Nodes.

Science.gov (United States)

Turgut, Eser; Celenk, Cetin; Tanrivermis Sayit, Asli; Bekci, Tumay; Gunbey, Hediye Pinar; Aslan, Kerim

2017-09-01

The purpose of this study was to evaluate the diagnostic accuracy and efficiency of ultrasonography (US), especially when combined with strain elastography (SE), in differentiating between benign and malignant cervical lymph nodes (LNs). Forty-one LNs were examined by B-mode US, power Doppler US, and SE. The following imaging features were analyzed: shape, echogenicity, echogenic hilum, calcification, intranodal vascular pattern, elasticity scores (5 categories), and strain ratio. The average strain ratio was calculated as the mean strain of the adjacent sternocleidomastoid muscle divided by the mean strain of the target LN. The results of the US and SE features were compared with the histopathologic findings. The imaging features that were significantly associated with malignant LNs were an increased short-to-long axis diameter ratio, abnormal or absence of hilum, microcalcification, type 2-3-4 vascularity, 3-4-5 elasticity scores, and a high level of strain ratio (P benign and malignant LNs. Strain elastography is useful in differentiating between benign and malignant cervical LNs, thereby informing decisions to perform a biopsy and/or surgery, and facilitating follow-up.

Tuning strain of granular matter by basal assisted Couette shear

Directory of Open Access Journals (Sweden)

Zhao Yiqiu

2017-01-01

Full Text Available We present a novel Couette shear apparatus capable of generating programmable azimuthal strain inside 2D granular matter under Couette shear. The apparatus consists of 21 independently movable concentric rings and two boundary wheels with frictional racks. This makes it possible to quasistatically shear the granular matter not only from the boundaries but also from the bottom. We show that, by specifying the collective motion of wheels and rings, the apparatus successfully generates the desired strain profile inside the sample granular system, which is composed of about 2000 photoelastic disks. The motion and stress of each particle is captured by an imaging system utilizing reflective photoelasticimetry. This apparatus provides a novel method to investigate shear jamming properties of granular matter with different interior strain profiles and unlimited strain amplitudes.

Speckle reduction in echocardiography by temporal compounding and anisotropic diffusion filtering

Science.gov (United States)

Giraldo-Guzmán, Jader; Porto-Solano, Oscar; Cadena-Bonfanti, Alberto; Contreras-Ortiz, Sonia H.

2015-01-01

Echocardiography is a medical imaging technique based on ultrasound signals that is used to evaluate heart anatomy and physiology. Echocardiographic images are affected by speckle, a type of multiplicative noise that obscures details of the structures, and reduces the overall image quality. This paper shows an approach to enhance echocardiography using two processing techniques: temporal compounding and anisotropic diffusion filtering. We used twenty echocardiographic videos that include one or three cardiac cycles to test the algorithms. Two images from each cycle were aligned in space and averaged to obtain the compound images. These images were then processed using anisotropic diffusion filters to further improve their quality. Resultant images were evaluated using quality metrics and visual assessment by two medical doctors. The average total improvement on signal-to-noise ratio was up to 100.29% for videos with three cycles, and up to 32.57% for videos with one cycle.

Frequency of echocardiographic complications of dilated cardiomyopathy at a tertiary care hospital

International Nuclear Information System (INIS)

Rashid, A.; Ahmed, H.N.; Ahmed, N.

2012-01-01

Dilated cardiomyopathy can lead to a variety of complications recognisable on clinical, echocardiographic, electrocardiographic and radiographic assessment. Among this, transthoracic echocardiography has the dual advantage of being helpful in making the diagnosis of dilated cardiomyopathy as well as an effective tool in early recognition of certain complications for timely management to improve the quality of life of these patients. Methods: This descriptive (case series) study was undertaken at departments of medicine, cardiology, paediatrics and obs/gyn, Ayub Teaching Hospital, Abbottabad from July to December, 2008. fifty patients of dilated cardiomyopathy without age and gender discrimination were selected by convenience sampling. Those with hypertrophic and restrictive cardiomyopathies, valvular and congenital heart disease, hypertension and ischemic heart disease were excluded. Results: mean age was 47.12 +- 17.9 year with male predominance (males=34, females=16). Mean ejection fraction was 30.6 +- 6.9%. complications revealed on echocardiography were intracardiac thrombi (5, 10%), spontaneous echo contrast (5, 10%), pericardial effusion (6, 12%), mitral regurgitation (46, 92%), tricuspid (25, 50%), aortic (5, 10%), pulmonary (2, 4%) multi-valvular regurgitation (28, 56%), and left atrial dilatation (36, 72%). Conclusion: lv systolic dysfunction, cardiac thrombi, spontaneous echo contrast, mitral and tricuspid regurgitation and left atrial enlargement are important complications of dilated cardiomyopathy. echocardiography is important tool towards identification of these complications. (author)

[Serial clinical and echocardiographic evaluation in children with Marfan syndrome].

Science.gov (United States)

Lopez, Victor Manuel Oporto; Perez, Ana Beatriz Alvarez; Moisés, Valdir Ambrósio; Gomes, Lourdes; Pedreira, Patricia da Silveira; Silva, Célia C; Campos Filho, Orlando; Carvalho, Antônio Carlos C

2005-11-01

To describe the clinical cardiac manifestations and temporal evolution of Marfan syndrome in children; to estimate the incidence of annuloaortic ectasia and mitral valve prolapse; and to evaluate tolerability and efficacy of beta-blockers in these patients. During one year, 21 children with Marfan syndrome underwent serial clinical and echocardiographic examinations. Echocardiograms assessed: the presence of mitral valve prolapse, aortic root diameter, mitral and aortic valves regurgitation, and aortic enlargement during beta-blocker therapy. Eleven patients had two measurements of the aortic root taken one year apart. The children were asymptomatic throughout the study. Mitral prolapse was found in 11 (52%) children. Annuloaortic ectasia occurred in 16 (76%) patients and found to be mild in 42.8%, moderate in 9.5%, and severe in 23.8%. One of these patients underwent aortic valve replacement and repair of the ascending aorta by the Bentall-De Bono technique, with good results. Heart rate decreased by 13.6% (from 85 to 73 bpm; p < 0.009) with the use of beta-blockers; however, aortic root diameter increased by 1.4 mm/year (p < 0.02). One child could not be given beta-blockers due to bronchial asthma, and no significant side effects were observed in the remaining children, including one who also had bronchial asthma. The children remained asymptomatic throughout the study, the use of beta-blockers led to a significant decrease in heart rate, and no significant adverse effects were observed. Contrary to the literature, incidence of annuloaortic ectasia was high among the study population, greater than that of mitral valve prolapse, even during beta-blocker therapy.

Subclinical Hypothyroidism and the Effect of Autoimmunity on the Echocardiography Indices of Left Ventricular Function, Lipid Profile, and Inflammatory Markers

Directory of Open Access Journals (Sweden)

Zohreh Moossavi

2015-03-01

Full Text Available Background: Subclinical hypothyroidism (Sch is the most frequent thyroid disease. The relationship between overt hypothyroidism and cardiovascular diseases has been well documented, but conflicting data have remained regarding Sch. Objectives: The present study aimed to assess the effect of Sch on increasing the risk of cardiovascular involvement considering the autoimmune subset. Patients and Methods: This case-control study was conducted on thirty patients with Sch and 30 healthy controls. Serum levels of thyroperoxidase antibody (TPOab, lipids, hsCRP, homocysteine, and ferritin were measured. Besides, conventional echocardiographic study and tissue Doppler imaging (including strain rate indices was done to evaluate Left Ventricular (LV systolic function. Results: The results showed a significant difference between the Sch patients and the controls regarding the serum level of triglyceride (117.43 ± 63.51 mg/dL vs. 86.86 ± 41.57, P = 0.031, echocardiographic parameters (longitudinal systolic strain rate [SRs: -1.006 ± 0.4 vs. -1.26 ± 0.16, P = 0.002; SRl: -1.43 ± 0.27 vs. -1.68 ± 0.29, P = 0.001], and Sm of septal mitral annulus (6.90 ± 0.6 vs. 7.43 ± 0.8, P = 0.006]. However, no significant difference was observed between the two groups regarding the serum levels of the inflammatory markers. Moreover, a significant correlation was found between TSH and Sm (r = -0.36, P = 0.005 and longitudinal systolic strain rate (SRs: r = 0.42, P < 0.001; SRl: r = 0.40, P = 0.001. Systolic strain rate was significantly lower in the TPOab positive patients (-0.99 ± 0.18 vs. -1.15 ± 0.25, P = 0.047. Conclusions: The clear association between Sch and subclinical LV systolic dysfunction which was more evident in the subgroup of patients with circulating anti-thyroid antibodies would remind a greater emphasis for considering the subgroup of TPOab positive patients for directing toward hormone replacement.

SALSA-A new instrument for strain imaging in engineering materials and components

International Nuclear Information System (INIS)

Pirling, Thilo; Bruno, Giovanni; Withers, Philip J.

2006-01-01

Residual stresses are very hard to predict and if undetected can lead to premature failure or unexpected behaviour of engineering materials or components. This paper describes the operation of a new residual strain-mapping instrument, Strain Analyser for Large and Small scale engineering Applications (SALSA), recently commissioned at the public user facility, the Institut Laue-Langevin in Grenoble, France. A unique feature of this neutron diffraction instrument is the sample manipulator, which is the first of its kind, allowing precise scanning of large and heavy (<500 kg) samples along any trajectory involving translations, tilts and rotations. Other notable features of the instrument are also described

Design and Validation of a Cyclic Strain Bioreactor to Condition Spatially-Selective Scaffolds in Dual Strain Regimes

Directory of Open Access Journals (Sweden)

J. Matthew Goodhart

2014-03-01

Full Text Available The objective of this study was to design and validate a unique bioreactor design for applying spatially selective, linear, cyclic strain to degradable and non-degradable polymeric fabric scaffolds. This system uses a novel three-clamp design to apply cyclic strain via a computer controlled linear actuator to a specified zone of a scaffold while isolating the remainder of the scaffold from strain. Image analysis of polyethylene terephthalate (PET woven scaffolds subjected to a 3% mechanical stretch demonstrated that the stretched portion of the scaffold experienced 2.97% ± 0.13% strain (mean ± standard deviation while the unstretched portion experienced 0.02% ± 0.18% strain. NIH-3T3 fibroblast cells were cultured on the PET scaffolds and half of each scaffold was stretched 5% at 0.5 Hz for one hour per day for 14 days in the bioreactor. Cells were checked for viability and proliferation at the end of the 14 day period and levels of glycosaminoglycan (GAG and collagen (hydroxyproline were measured as indicators of extracellular matrix production. Scaffolds in the bioreactor showed a seven-fold increase in cell number over scaffolds cultured statically in tissue culture plastic petri dishes (control. Bioreactor scaffolds showed a lower concentration of GAG deposition per cell as compared to the control scaffolds largely due to the great increase in cell number. A 75% increase in hydroxyproline concentration per cell was seen in the bioreactor stretched scaffolds as compared to the control scaffolds. Surprisingly, little differences were experienced between the stretched and unstretched portions of the scaffolds for this study. This was largely attributed to the conditioned and shared media effect. Results indicate that the bioreactor system is capable of applying spatially-selective, linear, cyclic strain to cells growing on polymeric fabric scaffolds and evaluating the cellular and matrix responses to the applied strains.

Cardiac resynchronization therapy by multipoint pacing improves response of left ventricular mechanics and fluid dynamics: a three-dimensional and particle image velocimetry echo study.

Science.gov (United States)

Siciliano, Mariachiara; Migliore, Federico; Badano, Luigi; Bertaglia, Emanuele; Pedrizzetti, Gianni; Cavedon, Stefano; Zorzi, Alessandro; Corrado, Domenico; Iliceto, Sabino; Muraru, Denisa

2017-11-01

To characterize the effect of multipoint pacing (MPP) compared to biventricular pacing (BiV) on left ventricle (LV) mechanics and intraventricular fluid dynamics by three-dimensional echocardiography (3DE) and echocardiographic particle imaging velocimetry (Echo-PIV). In 11 consecutive patients [8 men; median age 65 years (57-75)] receiving cardiac resynchronization therapy (CRT) with a quadripolar LV lead (Quartet,St.Jude Medical,Inc.), 3DE and Echo-PIV data were collected for each pacing configuration (CRT-OFF, BiV, and MPP) at follow-up after 6 months. 3DE data included LV volumes, LV ejection fraction (LVEF), strain, and systolic dyssynchrony index (SDI). Echo-PIV was used to evaluate the directional distribution of global blood flow momentum, ranging from zero, when flow force is predominantly along the base-apex direction, up to 90° when it becomes transversal. MPP resulted in significant reduction in end-diastolic and end-systolic volumes compared with both CRT-OFF (P = 0.02; P = 0.008, respectively) and BiV (P = 0.04; P = 0.03, respectively). LVEF and cardiac output were significant superior in MPP compared with CRT-OFF, but similar between MPP and BiV. Statistical significant differences when comparing global longitudinal and circumferential strain and SDI with MPP vs. CRT-OFF were observed (P = 0.008; P = 0.008; P = 0.01, respectively). There was also a trend towards improvement in strain between BiV and MPP that did not reach statistical significance. MPP reflected into a significant reduction of the deviation of global blood flow momentum compared with both CRT-OFF and BiV (P = 0.002) indicating a systematic increase of longitudinal alignment from the base-apex orientation of the haemodynamic forces. These preliminary results suggest that MPP resulted in significant improvement of LV mechanics and fluid dynamics compared with BiV. However, larger studies are needed to confirm this hypothesis. © Crown copyright 2016.

Echocardiographic study of cardiac dysfunction in patients of chronic kidney disease on hemodialysis

International Nuclear Information System (INIS)

Arshi, S.; Butt, G.U.D.; Mian, F.A.

2016-01-01

Objective: The objective of this study was to see echocardiographic findings of cardiac dysfunction in patients of chronic kidney disease (CKD) on hemodialysis. Study Design: Comparative cross sectional study. Place and Duration of Study: Department of nephrology, Pakistan Institute of Medical Sciences. Islamabad from September 2014 to February 2015. Patients and Methods: One hundred patients of either gender were included in this study. Fifty patients of chronic kidney disease stage V on hemodialysis were taken for echocardiography and fifty were normal. Echocardiography was done for cardiac dysfunction. Systolic function was measured by ejection fraction (EF) and fractional shortening (FS). Diastolic function was measured by E/A ratio. Results: Out of 100 patients included in the study, 50 patients were on hemodialysis and 50 were control. Left ventricular end systolic and end diastolic volumes were higher in patients on hemodialysis than controls as well as left atrial enlargement and inter ventricular septum which was statistically significant. Ejection fraction, although normal and fractional shortening decreased in patients on hemodialysis (p<0.05). Diastolic dysfunction was present in 36 patients on hemodialysis, while absent in the control group. Conclusion: Patients with chronic kidney disease on hemodialysis have higher prevalence of cardiac dysfunction. (author)

Archeological Echocardiography: Digitization and Speckle-Tracking Analysis of Archival Echocardiograms in the HyperGEN Study

Science.gov (United States)

Aguilar, Frank G.; Selvaraj, Senthil; Martinez, Eva E.; Katz, Daniel H.; Beussink, Lauren; Kim, Kwang-Youn A.; Ping, Jie; Rasmussen-Torvik, Laura; Goyal, Amita; Sha, Jin; Irvin, Marguerite R.; Arnett, Donna K.; Shah, Sanjiv J.

2015-01-01

Background Several large epidemiologic studies and clinical trials have included echocardiography, but images were stored in analog format and these studies predated tissue Doppler imaging (TDI) and speckle-tracking echocardiography (STE). We hypothesized that digitization of analog echocardiograms, with subsequent quantification of cardiac mechanics using STE, is feasible, reproducible, accurate, and produces clinically valid results. Methods In the NHLBI HyperGEN study (N=2234), archived analog echocardiograms were digitized and subsequently analyzed using STE to obtain tissue velocities/strain. Echocardiograms were assigned quality scores and inter/intraobserver agreement was calculated. Accuracy was evaluated in (1) a separate second study (N=50) comparing prospective digital strain vs. post-hoc analog-to-digital strain; and (2) in a third study (N=95) comparing prospectively-obtained TDI e′ velocities with post-hoc STE e′ velocities. Finally, we replicated previously known associations between tissue velocities/strain, conventional echocardiographic measurements, and clinical data. Results Of the 2234 HyperGEN echocardiograms, 2150 (96.2%) underwent successful digitization and STE analysis. Inter/intraobserver agreement was high for all STE parameters, especially longitudinal strain (LS). In accuracy studies, LS performed best when comparing post-hoc STE to prospective digital STE for strain analysis. STE-derived e′ velocities correlated with, but systematically underestimated, TDI e′ velocity. Several known associations between clinical variables and cardiac mechanics were replicated in HyperGEN. We also found a novel independent inverse association between fasting glucose and LS (adjusted β =−2.4 [95% CI −3.6,−1.2]% per 1-SD increase in fasting glucose; Pechocardiography, the digitization and speckle-tracking analysis of archival echocardiograms, is feasible and generates parameters of cardiac mechanics similar to contemporary studies. PMID

Archeological Echocardiography: Digitization and Speckle Tracking Analysis of Archival Echocardiograms in the HyperGEN Study.

Science.gov (United States)

Aguilar, Frank G; Selvaraj, Senthil; Martinez, Eva E; Katz, Daniel H; Beussink, Lauren; Kim, Kwang-Youn A; Ping, Jie; Rasmussen-Torvik, Laura; Goyal, Amita; Sha, Jin; Irvin, Marguerite R; Arnett, Donna K; Shah, Sanjiv J

2016-03-01

Several large epidemiologic studies and clinical trials have included echocardiography, but images were stored in analog format and these studies predated tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE). We hypothesized that digitization of analog echocardiograms, with subsequent quantification of cardiac mechanics using STE, is feasible, reproducible, accurate, and produces clinically valid results. In the NHLBI HyperGEN study (N = 2234), archived analog echocardiograms were digitized and subsequently analyzed using STE to obtain tissue velocities/strain. Echocardiograms were assigned quality scores and inter-/intra-observer agreement was calculated. Accuracy was evaluated in: (1) a separate second study (N = 50) comparing prospective digital strain versus post hoc analog-to-digital strain, and (2) in a third study (N = 95) comparing prospectively obtained TDI e' velocities with post hoc STE e' velocities. Finally, we replicated previously known associations between tissue velocities/strain, conventional echocardiographic measurements, and clinical data. Of the 2234 HyperGEN echocardiograms, 2150 (96.2%) underwent successful digitization and STE analysis. Inter/intra-observer agreement was high for all STE parameters, especially longitudinal strain (LS). In accuracy studies, LS performed best when comparing post hoc STE to prospective digital STE for strain analysis. STE-derived e' velocities correlated with, but systematically underestimated, TDI e' velocity. Several known associations between clinical variables and cardiac mechanics were replicated in HyperGEN. We also found a novel independent inverse association between fasting glucose and LS (adjusted β = -2.4 [95% CI -3.6, -1.2]% per 1-SD increase in fasting glucose; P echocardiography, the digitization and speckle tracking analysis of archival echocardiograms, is feasible and generates indices of cardiac mechanics similar to contemporary studies. © 2015, Wiley Periodicals, Inc.

Effect of dobutamine on a Doppler echocardiographic index of combined systolic and diastolic performance.

Science.gov (United States)

Harada, K; Tamura, M; Toyono, M; Yasuoka, K

2002-01-01

Dobutamine stress echocardiography has become accepted in the evaluation of cardiac functional reserve. Although the Doppler-derived index of combined systolic/diastolic myocardial performance (Tei index) has been reported to be easily obtainable and useful for predicting left ventricular performance, the effect of dobutamine on the Tei index has not been determined in children. To assess the effect of dobutamine on the Tei index, 8 patients who had undergone surgery for ventricular septal defect and 7 patients who had a history of Kawasaki disease were examined. Echocardiographic recordings were obtained before and after dobutamine infusion (5 microg/kg per minute). Variables measured were transmitral flow velocities (E, A, E/A), rate-corrected mean velocity of circumferential fiber shortening (rate-corrected Vcf), and IMP. We measured isovolumic contraction time (ICT), isovolumic relaxation time (IRT), and ejection time (ET) and then calculated the Tei index using the following formula: Tei index = (ICT + IRT)/ET. Dobutamine infusion increased rate-corrected Vcf (29%, p ICT, and IRT were found to decrease during dobutamine infusion. The magnitude of the change in the ICT (-21%, p ICT/ET (-21%, p effects of inotropic stimilation on global left ventricular function.

Biomechanical Analysis of Normal Brain Development during the First Year of Life Using Finite Strain Theory

OpenAIRE

Kim, Jeong Chul; Wang, Li; Shen, Dinggang; Lin, Weili

2016-01-01

The first year of life is the most critical time period for structural and functional development of the human brain. Combining longitudinal MR imaging and finite strain theory, this study aimed to provide new insights into normal brain development through a biomechanical framework. Thirty-three normal infants were longitudinally imaged using MRI from 2 weeks to 1 year of age. Voxel-wise Jacobian determinant was estimated to elucidate volumetric changes while Lagrange strains (both normal and...

Strain Dependence of Photoluminescense of Individual Carbon Nanotubes

Science.gov (United States)

Nikolaev, Pavel N.; Leeuw, Tonya K.; Tsyboulski, Dmitri A.; Bachilo, Sergei M.; Weisman, Bruce; Arepalli, Sivaram

2007-01-01

We have investigated strain dependence of photoluminescense (PL) spectra of single wall carbon nanotubes (SWNT). Nanotubes were sparsely dispersed in a thin PMMA film applied to acrylic bar, and strained in both compression and extension by bending this bar in either direction in a homebuilt four-point bending rig. The average surface strain was measured with high accuracy by a resistive strain gage applied on top of the film. The near infrared imaging and spectroscopy were performed on the inverted microscope equipped with high numerical aperture reflective objective lens and InGaAs CCD cameras. PL was excited with a diode laser at either 658, 730 or 785 nm, linearly polarized in the direction of the strain. We were able to measure (n,m) types and orientation of individual nanotubes with respect to strain direction and strain dependence of their PL maxima. It was found that PL peak shifts with respect to the values measured in SDS micelles are a sum of three components. First, a small environmental shift due to difference in the dielectric constant of the surrounding media, that is constant and independent of the nanotube type. Second, shift due to isotropic compression of the film during drying. Third, shifts produced by the uniaxial loading of the film in the experiment. Second and third shifts follow expression based on the first-order expansion of the TB hamiltonian. Their magnitude is proportional to the nanotube chiral angle and strain, and direction is determined by the nanotube quantum number. PL strain dependence measured for a number of various nanotube types allows to estimate TB carbon-carbon transfer integral.

Automated assessments of circumferential strain from cine CMR correlate with LVEF declines in cancer patients early after receipt of cardio-toxic chemotherapy.

Science.gov (United States)

Jolly, Marie-Pierre; Jordan, Jennifer H; Meléndez, Giselle C; McNeal, Gary R; D'Agostino, Ralph B; Hundley, W Gregory

2017-08-02

In patients with cancer receiving potentially cardio-toxic chemotherapy, measurements of left ventricular (LV) circumferential or longitudinal strain are often used clinically to identify myocardial dysfunction. Using a new software algorithm, we sought to determine in individuals receiving treatment for cancer the association between automated assessments of LV mean mid-wall circumferential strain and conventional measures of LV ejection fraction (EF) both obtained from cardiovascular magnetic resonance (CMR) cine balanced steady-state free-precession (bSSFP) white-blood acquisitions. Before and 3 months after initiating treatment with potentially cardio-toxic chemotherapy, 72 individuals (aged 54 ± 14 years with breast cancer [39%], lymphoma [49%], or sarcoma [12%]) underwent serial CMR cine bSSFP assessments of LV volumes and EF, and mean mid-wall circumferential strain determined from these same cine images as well as from additional tagged CMR images. On the cine images, assessments of strain were obtained using the newly developed deformation-based segmentation algorithm. Assessments of LV volumes/EF from the cine images and strain from tagged CMR were accomplished using commercially available software. All measures were analyzed in a blinded fashion independent of one another. Acceptable measures for the automated assessments of mean mid-wall circumferential strain from the cine images were obtained in 142 of 144 visits (98.6%) with an overall analysis time averaging 6:47 ± 1:06 min. The results from these automated measures averaged -18.8 ± 2.9 at baseline and -17.6 ± 3.1 at 3 months (p = 0.001). Left ventricular EF declined slightly from 65 ± 7% at baseline to 62 ± 7% at 3 months (p = 0.0002). The correlation between strain from cine imaging and LVEF was r = -0.61 (p cine and tagged derived assessments of strain was r = 0.23; p = 0.01. Automated measures of LV mean mid-wall circumferential strain can be obtained in 6�

The influence of angle of insonation and target depth on speckle-tracking strain

DEFF Research Database (Denmark)

Forsha, Daniel; Risum, Niels; Rajagopal, Sudarshan

2015-01-01

was to assess the influence of angle and depth on longitudinal peak systolic strain (LPS). METHODS: Thirty-four healthy pediatric subjects (age range, 6-18 years; 47% male) with normal cardiac anatomy and good image quality were prospectively imaged. Angular comparisons of LPS were investigated by examining...

Synchronized epiaortic two-dimensional and color Doppler echocardiographic guidance enables routine ascending aortic cannulation in type A acute aortic dissection.

Science.gov (United States)

Inoue, Yoshito; Takahashi, Ryuichi; Ueda, Toshihiko; Yozu, Ryohei

2011-02-01

Preference for arterial inflow during surgery for type A acute aortic dissection remains controversial. Antegrade central perfusion prevents malperfusion and retrograde embolism, and the ascending aorta provides arterial access for rapid establishment of systemic perfusion, especially if there is hemodynamic instability. It has not been used routinely, however, because of the disruption caused to the aorta. We evaluated the safety and efficacy of routine cannulation of the dissected aorta for the repair of type A dissection. Surgical results were analyzed for 83 consecutive patients with type A acute aortic dissection between 2002 and 2009. They were treated surgically by prosthetic graft replacement under hypothermic circulatory arrest. The ascending aorta was routinely cannulated using the Seldinger technique with epiaortic echocardiographic guidance; antegrade systemic perfusion was evaluated by color Doppler ultrasound. Systemic antegrade perfusion via the dissected ascending aorta was performed safely in all cases. There was no malperfusion or thromboembolism as a result of ascending aortic cannulation. Epiaortic 2-dimensional and color Doppler imaging provided real-time monitoring adequate for the placement and for proper systemic perfusion. There were 5 in-hospital deaths (5/83=6.0%) and 8 strokes (preoperative 6/83=7.2%, postoperative 2/83=2.4%). A total of 78 patients (78/83=94%) were discharged and have been followed up without major adverse cardiac events for a mean duration of 31.8 months. Ascending aortic cannulation is a simple and safe technique that provides a rapid and reliable route of antegrade central systemic perfusion in type A aortic dissection. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Spectrum of heart diseases in children: an echocardiographic study of 1,666 subjects in a pediatric hospital, Yaounde, Cameroon.

Science.gov (United States)

Chelo, David; Nguefack, Félicitée; Menanga, Alain P; Ngo Um, Suzanne; Gody, Jean C; Tatah, Sandra A; Koki Ndombo, Paul O

2016-02-01

Children's health programs in Sub-Saharan Africa have always been oriented primarily to infectious diseases and malnutrition. We are witnessing in the early 21(st) century an epidemiological transition marked by the decline of old diseases and the identification of new diseases including heart disease. Therefore, it is necessary to describe the spectrum of these diseases in order to better prepare health workers to these new challenges. We conducted a cross-sectional study focused on heart disease diagnosed by echocardiography in children seen from January 2006 to December 2014 in a pediatric hospital of Yaounde. We collected socio-demographic data and the types of heart disease from registers, patients files as well as the electronic database of echocardiographic records. A total of 2,235 patients underwent echocardiographic examination during the study period including 1,666 subjects with heart disease. Congenital cardiopathies were found in 1,230 (73.8%) patients and acquired abnormalities in 429 (25.8%). Seven children (0.4%) had a combination of both types. Congenital heart defects (CHD) were dominated by ventricular septal defect (VSD). Acquired heart disease was mostly rheumatic valvulopathies. Dyspnea on exertion was the most frequent presenting complaint (87.6%). Discovery of a heart murmur was the principal clinical finding on physical examination (81.4%). The median age was 9 months for congenital heart disease and 132 months for acquired heart disease. As infectious diseases recede and the diagnostic facilities are improving, pediatric heart diseases occupy a more important position in the spectrum of pediatric diseases in our context. However, the ability to evoke the diagnosis remains unsatisfactory by the majority of health personnel and therefore needs to be improved. Apart from congenital heart diseases, the impact of acquired heart diseases, rheumatic valvulopathy being the highest ranking, is remarkable in pediatrics. Awareness of health

Field Strain Measurement on the Fiber-Epoxy Scale in CFRPs

KAUST Repository

Tao, Ran

2015-06-08

Laminated composites are materials with complex architecture made of continuous fibers (usually glass or carbon) embedded within a polymeric resin. The properties of the raw materials can vary from one point to another due to different local processing conditions or complex geometrical features for example. A first step towards the identification of these spatially varying material parameters is to image with precision the displacement fields in this complex microstructure when subjected to mechanical loading. Secondary electron images obtained by scanning electron microscopy (SEM) and then numerically deformed are post-processed by either local subset-based digital image correlation (DIC) or global finite-element based DIC to measure the displacement and strain fields at the fiber-matrix scale in a cross-ply composite. It is shown that when global DIC is applied with a conformal mesh, it can capture more accurate local variations in the strain fields as it takes into account the underlying microstructure. In comparison to subset DIC, global DIC is better suited for capturing gradients across the fiber-matrix interfaces.

Left atrioventricular remodeling in the assessment of the left ventricle diastolic function in patients with heart failure: a review of the currently studied echocardiographic variables

Directory of Open Access Journals (Sweden)

Köhler Ilmar

2008-11-01

Full Text Available Abstract Multiparametric echocardiographic imaging of the failing heart is now increasingly used and useful in decision making in heart failure. The reasons for this, relies on the need of different strategies of handling these patients, as differentiation of systolic or diastolic dysfunction, as well as on the gamma of approaches available, such as percutaneous and surgical revascularization, devices implantations, and valvular regurgitations and stenosis corrections. Congestive heart failure in patients with normal left ventricular diameters or preserved left ventricular ejection fraction had been pointed out recently as present in a proportion so high as 40 to 50 percent of cases of heart failure, mainly due to the epidemics in well developed countries, as is the problem of not well controlled metabolic states (such as obesity and diabetes, but also due to the real word in developing countries, as is the case of hypertension epidemics and its lack of adequate control. As a matter of public utility, the guidelines in the diagnosis and treatment of such patients will have to be cheap, available, easily reproducible, and ideally will furnish answers for the clinician questions not in a binary "black or white" manner, but with graduations, so if possible it has to be quantitative. The present paper aim to focus on the current clinical applications of tissue Doppler and of left atrial function and remodeling, and its pathophysiologic relationship with the left ventricle, as will be cleared in the documented review of echocardiography that follows, considering that the need of universal data on the syndrome of the failing heart does not mean, unfortunately, that all patients and clinicians in developing countries have at their own health facilities the same imaging tools, since they are, as a general rule, expensive.

Effect of bone-soft tissue friction on ultrasound axial shear strain elastography.

Science.gov (United States)

Tang, Songyuan; Chaudhry, Anuj; Kim, Namhee; Reddy, J N; Righetti, Raffaella

2017-07-12

Bone-soft tissue friction is an important factor affecting several musculoskeletal disorders, frictional syndromes and the ability of a bone fracture to heal. However, this parameter is difficult to determine using non-invasive imaging modalities, especially in clinical settings. Ultrasound axial shear strain elastography is a non-invasive imaging modality that has been used in the recent past to estimate the bonding between different tissue layers. As most elastography methods, axial shear strain elastography is primarily used in soft tissues. More recently, this technique has been proposed to assess the bone-soft tissue interface. In this paper, we investigate the effect of a variation in bone-soft tissue friction coefficient in the resulting axial shear strain elastograms. Finite element poroelastic models of bone specimens exhibiting different bone-soft tissue friction coefficients were created and mechanically analyzed. These models were then imported to an ultrasound elastography simulation module to assess the presence of axial shear strain patterns. In vitro experiments were performed to corroborate selected simulation results. The results of this study show that the normalized axial shear strain estimated at the bone-soft tissue interface is statistically correlated to the bone-soft tissue coefficient of friction. This information may prove useful to better interpret ultrasound elastography results obtained in bone-related applications and, possibly, monitor bone healing.

Advanced Magnetic Resonance Imaging techniques to probe muscle structure and function

Science.gov (United States)

Malis, Vadim

Structural and functional Magnetic Resonance Imaging (MRI) studies of skeletal muscle allow the elucidation of muscle physiology under normal and pathological conditions. Continuing on the efforts of the Muscle Imaging and Modeling laboratory, the focus of the thesis is to (i) extend and refine two challenging imaging modalities: structural imaging using Diffusion Tensor Imaging (DTI) and functional imaging based on Velocity Encoded Phase Contrast Imaging (VE-PC) and (ii) apply these methods to explore age related structure and functional differences of the gastrocnemius muscle. Diffusion Tensor Imaging allows the study of tissue microstructure as well as muscle fiber architecture. The images, based on an ultrafast single shot Echo Planar Imaging (EPI) sequence, suffer from geometric distortions and low signal to noise ratio. A processing pipeline was developed to correct for distortions and to improve image Signal to Noise Ratio (SNR). DTI acquired on a senior and young cohort of subjects were processed through the pipeline and differences in DTI derived indices and fiber architecture between the two cohorts were explored. The DTI indices indicated that at the microstructural level, fiber atrophy was accompanied with a reduction in fiber volume fraction. At the fiber architecture level, fiber length and pennation angles decreased with age that potentially contribute to the loss of muscle force with age. Velocity Encoded Phase Contrast imaging provides tissue (e.g. muscle) velocity at each voxel which allows the study of strain and Strain Rate (SR) under dynamic conditions. The focus of the thesis was to extract 2D strain rate tensor maps from the velocity images and apply the method to study age related differences. The tensor mapping can potentially provide unique information on the extracellular matrix and lateral transmission the role of these two elements has recently emerged as important determinants of force loss with age. In the cross sectional study on

Evaluation of Cardiovascular System in Fibromyalgia Syndrome: Tissue Doppler Echocardiographic Investigation

Directory of Open Access Journals (Sweden)

Selma YAZICI

2010-05-01

Full Text Available Aim: We aim to investigate besides the cardiac structures and functions by both conventionalmethods and Tissue Doppler Echocardiography (TDE which is a new and useful method inpatients with Fibromyalgia (FM. Additionally, we evaluated QT parameters (QT maximum,QT minimum and QT dispertion with the use of electrocardiography in order to measure theautonomic dysfunction which is a possible mechanism in the pathogenesis of the disease. Methods: The study was performed on 42 patients (mean age 41 years, 38 female and 38completely healthy subjects (35 female, mean age of 42 years who were admitted to the sameclinic were collected as the control group. All the individuals were undergone a completephysical examination, electrocardiography (recordings were displayed at 50 mm/s speed andechocardiography evaluation (both conventional methods and TDE.Results: Analysis of electrocardiographic recordings revealed mildly increased mean QTdispertion in the patient group, but this difference was statistically insignificant. Analysis ofconventional echocardiographic parameters revealed similar results between the patient groupand the control cases. However, an important finding of this study is that significant diastolicdysfunction was found in the patient group which was recorded with the TDE technique. Emwave velocity and Em/Am ratios were significantly lower in patients with FM compared withcontrols (p<0.005, p<0.01, respectively. Sm and Am waves velocities were similar in bothgroups. Conclusion: In this study, significant left ventricular diastolic dysfunction which was detectedby TDE technique can partly explain several symptoms such as fatigue and dyspnea in FM. Inaddition, fully cardiac evaluation of patients with FM might be obtained supporting findingsthe autonomic dysfunction theory in fibromyalgia pathogenesis.

Initial Surgical Experience with Aortic Valve Repair: Clinical and Echocardiographic Results

Directory of Open Access Journals (Sweden)

Francisco Diniz Affonso da Costa

Full Text Available Abstract Introduction: Due to late complications associated with the use of conventional prosthetic heart valves, several centers have advocated aortic valve repair and/or valve sparing aortic root replacement for patients with aortic valve insufficiency, in order to enhance late survival and minimize adverse postoperative events. Methods: From March/2012 thru March 2015, 37 patients consecutively underwent conservative operations of the aortic valve and/or aortic root. Mean age was 48±16 years and 81% were males. The aortic valve was bicuspid in 54% and tricuspid in the remaining. All were operated with the aid of intraoperative transesophageal echocardiography. Surgical techniques consisted of replacing the aortic root with a Dacron graft whenever it was dilated or aneurysmatic, using either the remodeling or the reimplantation technique, besides correcting leaflet prolapse when present. Patients were sequentially evaluated with clinical and echocardiographic studies and mean follow-up time was 16±5 months. Results: Thirty-day mortality was 2.7%. In addition there were two late deaths, with late survival being 85% (CI 95% - 68%-95% at two years. Two patients were reoperated due to primary structural valve failure. Freedom from reoperation or from primary structural valve failure was 90% (CI 95% - 66%-97% and 91% (CI 95% - 69%-97% at 2 years, respectively. During clinical follow-up up to 3 years, there were no cases of thromboembolism, hemorrhage or endocarditis. Conclusions: Although this represents an initial series, these data demonstrates that aortic valve repair and/or valve sparing aortic root surgery can be performed with satisfactory immediate and short-term results.

High-resolution spatiotemporal strain mapping reveals non-uniform deformation in micropatterned elastomers

Science.gov (United States)