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Littérature scientifique sur le sujet « Strain longitudinale globale »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Strain longitudinale globale"

Galderisi, Maurizio, et Bruno Trimarco. « Global longitudinal strain ». Journal of Hypertension 34, n^o 6 (juin 2016) : 1050–51. http://dx.doi.org/10.1097/hjh.0000000000000920.

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Haugaa, Kristina H., et Lars A. Dejgaard. « Global Longitudinal Strain ». Journal of the American College of Cardiology 71, n^o 18 (mai 2018) : 1958–59. http://dx.doi.org/10.1016/j.jacc.2018.03.015.

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Reiber, Johan H. C. « Global longitudinal strain (GLS) ». International Journal of Cardiovascular Imaging 38, n^o 2 (février 2022) : 269–70. http://dx.doi.org/10.1007/s10554-022-02556-5.

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Kwong, Raymond Y., Christopher M. Kramer et Y. Chandrashekhar. « CMR Global Longitudinal Strain ». JACC : Cardiovascular Imaging 11, n^o 10 (octobre 2018) : 1554–55. http://dx.doi.org/10.1016/j.jcmg.2018.09.002.

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D’Elia, Nicholas, Stefano Caselli, Wojciech Kosmala, Patrizio Lancellotti, Daniel Morris, Denisa Muraru, Masaaki Takeuchi et al. « Normal Global Longitudinal Strain ». JACC : Cardiovascular Imaging 13, n^o 1 (janvier 2020) : 167–69. http://dx.doi.org/10.1016/j.jcmg.2019.07.020.

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Reddy, Abhinay, Vasvi Singh, Badri Karthikeyan, Leyi Jiang, Silva Kristo, Sharma Kattel, Ram Amuthan, Saraswati Pokharel et Umesh C. Sharma. « Biventricular Strain Imaging with Cardiac MRI in Genotyped and Histology Validated Amyloid Cardiomyopathy ». Cardiogenetics 11, n^o 3 (30 juin 2021) : 98–110. http://dx.doi.org/10.3390/cardiogenetics11030011.

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Cardiac amyloidosis (CA) is a common and potentially fatal infiltrative cardiomyopathy. Contrast-enhanced cardiac MRI (CMR) is used as a diagnostic tool. However, utility of CMR for the comprehensive analysis of biventricular strains and strain rates is not reported as extensively as echocardiography. In addition, RV strain analysis using CMR has not been described previously. Objectives: We sought to study the global and regional indices of biventricular strain and strain rates in endomyocardial biopsy (EMB)-proven, genotyped cases of CA. Methods: A database of 80 EMBs was curated from 2012 to 2019 based on histology. A total of 19 EMBs positive for CA were subjected to further tissue-characterization with histology, and compared with four normal biopsy specimens. Samples were genotyped for ATTR- or AL-subtypes. Five patients, with both echocardiography and contrast-enhanced CMR performed 72-h apart, were subjected to comprehensive analysis of biventricular strain and strain-rates. Results: Histology confirmed that the selected samples were indeed positive for cardiac amyloid. Echocardiography showed reduced global and regional left-ventricular (LV) longitudinal strain indices. CMR with tissue-characterization of LV showed global reductions in circumferential, radial and longitudinal strains and strain-rates, following a general trend with the echocardiographic findings. The basal right-ventricular (RV) segments had reduced circumferential strains with no changes in longitudinal strain. Conclusions: In addition to providing a clinical diagnosis of CA based on contrast clearance-dynamics, CMR can be a potent tool for accurate functional assessment of global and regional changes in strain and strain-rates involving both LV and RV. Further studies are warranted to validate and curate the strain imaging capacity of CMR in CA.

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Yeong, C., et W. Wang. « Is Manually Measured Global Longitudinal Strain a Reliable Alternative to Speckle Tracking Global Longitudinal Strain ? » Heart, Lung and Circulation 31 (2022) : S166. http://dx.doi.org/10.1016/j.hlc.2022.06.261.

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Chernykh, Nadezhda, Alla Tarasova et Olga Groznova. « 2D speckle-tracking in assessment of myocardial strain in children with hypertrophic cardiomyopathy ». Acta Medico-Biotechnica 14, n^o 2 (12 juin 2022) : 10–17. http://dx.doi.org/10.18690/actabiomed.219.

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Purpose: To assess the myocardial strain in children with hypertrophic cardiomyopathy (HCM). Methods: A total of 61 patients aged between 7 and 17 years with an asymmetric form of HCM underwent an ultrasound examination of the heart using standard techniques. An assessment of the left ventricular systolic function was performed using the two-dimensional (2D) speckle-tracking mode with analysis parameters that included global and segmental longitudinal, circumferential, and radial myocardial strains. Strain data for the subendocardial and subepicardial layers for each segment of the left ventricle, as well as their total values, were determined. Results: Global longitudinal strain and longitudinal strain rate were dec reased due to the impaired contractility of hypertrophied myocardial segments in 100% of cases of non-obstructive and obstructive HCM forms. A decrease in global, radial, and circumferential strain parameters and their rates has been observed in all children with an obstructive form of HCM and 39 (86.6%) patients with non-obstructive form. At the same time, there was a statistically significant difference between strains and strain rates in children with a non-obstructive form of HCM in comparison to those with an obstructive form of the disease. Conclusion: Changes in myocardial strains observed using the 2D speckle-tracking mode in children with HCM indicate early systolic dysfunction of the left ventricle. Longitudinal strain was the most sensitive compared to radial and circumferential types. It was statistically significantly different in children with an obstructive form of HCM compared to those with non-obstructive form of the disease. These results are important for early therapy initiation and, therefore, may improve prognosis in children with HCM.

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Støylen, Asbjørn, Harald Edvard Mølmen et Håvard Dalen. « Left ventricular global strains by linear measurements in three dimensions : interrelations and relations to age, gender and body size in the HUNT Study ». Open Heart 6, n^o 2 (septembre 2019) : e001050. http://dx.doi.org/10.1136/openhrt-2019-001050.

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BackgroundStrain is a relative deformation and has three dimensions, in the left ventricle (LV) usually longitudinal (εL), transmural (εT) and circumferential (εC) strain. All three components can be measured generically by the basic systolic and diastolic dimension measures of LV wall length, wall thickness and diameter. In this observational study we aimed to study the relations of normal generic strains to age, body size and gender, as well as the interrelations between the three strain components.MethodsGeneric strains derived from dimension measures by longitudinal and cross-sectional M-mode in all three dimensions were measured in 1266 individuals without heart disease from the Nord-Trøndelag Health Study.ResultsThe mean εL was −16.3%, εC was −22.7% and εT was 56.5%. Normal values by age and gender are provided. There was a gradient of εC from the endocardial, via the midwall to the external level, lowest at the external. All strains decreased in absolute values by increasing body surface area (BSA) and age, relations were strongest for εL. Gender differences were mainly a function of BSA differences. The three strain components were strongly interrelated through myocardial incompressibility.ConclusionsGlobal systolic strain is the total deformation of the myocardium; the three strain components are the spatial coordinates of this deformation, irrespective of the technology used for measurement. Normal values are method-dependent and not normative across methods. Interrelation of strains indicates a high degree of myocardial incompressibility and that longitudinal strain carries most of the total information.

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Moslehi, Javid J., et Ronald M. Witteles. « Global Longitudinal Strain in Cardio-Oncology ». Journal of the American College of Cardiology 77, n^o 4 (février 2021) : 402–4. http://dx.doi.org/10.1016/j.jacc.2020.12.014.

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Thèses sur le sujet "Strain longitudinale globale"

ALLONI, MARTA. « Studio multicentrico di valutazione multiparametrica cardiovascolare ultrasonografica nella predizione della coronaropatia ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/45258.

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Ad oggi la malattia cardiovascolare aterosclerotica rimane la principale causa di morbidità e mortalità (58% di morte per tutte le cause, di cui il 75% per coronaropatia e il 25% per ictus e ischemia cerebrale), e sarà la principale causa di mortalità nel 2015 secondo un rapporto della WHO. Il problema principale è legato al lungo tempo che intercorre tra l’inizio dello sviluppo di aterosclerosi nel giovane adulto e la sua manifestazione alcune decadi dopo. E’ di primaria importanza quindi poter identificare i soggetti a rischio di eventi cardiovascolari con progetti di prevenzione primaria in ogni paese, come raccomandato da diverse linee guida, comprese quelle della Società Europea di Cardiologia per la prevenzione del rischio cardiovascolare nella pratica clinica. Sono stati proposti diversi modi per stratificare il rischio cardiovascolare: fra i più importanti è stato sviluppato il Framngham risk score, che calcola la probabilità di mortalità coronarica a 10 anni a seconda della presenza dei seguenti fattori di rischio: età, presenza di diabete, fumo, pressione arteriosa, colesterolemia totale e LDL. Esistono dunque vari modi di stratificare il rischio in un soggetto asintomatico, tra carte del rischio (Framingham Risk score, SCORE, Progetto Cuore in Italia) e diversi indici bioumorali (ad esempio PCR e fibrinogeno) e strumentali: questi si adattano bene come predittori sulla popolazione generale, ma nessuno è utile nello stimare il rischio reale del singolo paziente per eventi cardiovascolari. Infatti, il rischio soggettivo è dato anche dal rischio complessivo della popolazione in cui il soggetto vive. Anche l’identificazione precoce del danno d’organo subclinico, come indicato dalle linee guida ESH/ESC, è uno degli obiettivi più importanti di prevenzione e trattamento del rischio cardiovascolare.Infatti la presenza di ipertrofia ventricolare sinistra, ispessimento medio-intimale carotideo, microalbuminuria, aumentata stiffness arteriosa aumentano il rischio cardiovascolare, indipendentemente dalla pressione arteriosa, in presenza o assenza di trattamento. Quindi parità di valori pressori, pazienti che presentano danno d’organo hanno un maggior rischio cardiovascolare e necessitano di una terapia più aggressiva e precoce. L’uso dell’ultrasonografia si adatta bene come screening del rischio cardiovascolare di popolazioni non selezionate, perché a basso costo rispetto a metodiche a maggior impatto rischio /beneficio,a maggior costo e a maggior esposizione di radiazioni come la TAC e la RMN cardiaca, inoltre è una metodica non invasiva. Infatti per eseguire uno screening bisogna che gli strumenti utilizzati siano validati, precisi, facili da utilizzare e soprattutto non invasivi. Inoltre è necessario che vi sia personale esperto, a basso costo per il sistema sanitario nazionale, la metodica non dovrebbe avere effetti biologici negativi ed essere giustificata dai risultati. L’ecografia può permettere di studiare i parametri che per primi si modificano nel processo aterosclerotico come la rigidità arteriosa e lo spessore mio intimale carotideo, i parametri di funzione longitudinale ventricolare sinistra (strain e strain rate), la velocità basale di flusso della coronaria interventricolare anteriore ed infine l’accumulo di calcio a livello delle strutture cardiache (valvole, muscoli papillari, radice aortica).

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Lam, Cecilia. « Jämförelse av global longitudinell strain mellan två ekokardiografiska mjukvaruprogram ». Thesis, Malmö universitet, Fakulteten för hälsa och samhälle (HS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-25721.

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Idag är ekokardiografi den dominerande undersökningsmetoden för att studera hjärtat. Ekokardiografi kan med hjälp av ultraljud avbilda hjärtat utifrån olika projektioner som kan antingen sparas som stillbilder eller rörliga sekvenser. Ultraljud av hjärtat är en icke-invasiv teknik som kan utföras snabbt och orsakar därmed inget obehag för patienten. Global longitudinell strain (GLS) är ett vanligt mått inom ekokardiografi. GLS används allt oftare i kliniskt syfte för att bland annat följa behandlingsresultat och dessutom för tidig upptäckt av förändringar i myokardiet. Syftet med denna studie var att utreda om det fanns någon signifikant skillnad av mätvärden GLS mellan de två olika mjukvaruprogrammen, EchoPac och TomTec. I studien inkluderades 30 patienter, där sinusrytm och en god bildkvalité kunde erhållas. Mann-Whitney U test visade på en signifikant skillnad med P-värde 0,042. Bland-Altmandiagrammet visade på att alla värden, 30 totalt, förutom tre värden förhåller sig inom ett 95% konfidensintervall. Slutsatsen är att det finns en skillnad avseende GLS mellan de två mjukvaruprogrammen, utifrån denna studie. Analys av GLS hos samma patient bör utföras med samma mjukvaruprogram för att minimera variation av mätvärden så mycket som möjligt.
Echocardiography is today the dominant examination method for studying the heart. Echocardiography can with help of ultrasound provide an image of the heart from various projections that can either be saved as still images or moving sequences. Ultrasound of the heart is a non-invasive technique that can be performed quickly and thus causes no discomfort to the patient. Global longitudinal strain (GLS) is a common measure in echocardiography. GLS is increasingly used in clinical practice to monitor treatment outcome and to detect early changes in the myocardium. The purpose of this study was to determine if there were any significant difference in the measurement values of GLS between two different software programs, EchoPac and TomTec. The study included 30 patients with sinus rhythm and good image quality. The Mann-Whitney U test showed a significant difference of P 0.042. The Bland-Altman diagram showed that all values, 30 in total, except of three, are within a 95% confidence interval. The conclusion is that there is a difference of GLS between the two software programs, based on this study. Analysis of GLS in the same patient should be performed with the same software program to minimize measurement errors as much as possible.

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Baker, Sinan, et Odai Alcharif. « Ekokardiografi : jämförelse av erfarenhetens betydelse vid mätningar av strain och strain rate i vänster kammare ». Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-44342.

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Bakgrund: Ekokardiografi har en betydande roll i diagnostisering av vänster kammare. Genom undersökning av segmentell och global longitudinell strain samt strain rate kan regional och global kinetik bedömas. Vid kontraktion och relaxation deformeras myokardiet varvid segmentell strain mäter deformationen av respektive segment uttryckt i procent medan strain rate mäter hastigheten av deformationen. Genom summering av medelvärdet från alla segment erhålls global longitudinell strain. Syfte: Syftet med studien var att jämföra ultraljudbaserade segmentell och global strain samt strain rate i vänster kammare. Jämförelse har gjorts mellan mätningar utförd av erfaren biomedicinsk analytiker samt mindre erfarna biomedicinska analytikerstudenter. Metod: Kvantitativ studie där 10 testpersoner undersökts ekokardiografiskt. Bildtagningen och mätresultaten insamlades med Siemens Acuson SC2000. Sammanställning av insamlade mätvärden gjordes på Microsoft Excel och Microsoft Word i diagram och tabeller. För jämförelse av strain segmentellt och globalt samt strain rate har analysmetoden Related-Samples Wilcoxon Signed Rank Test använts. Resultat: Resultatet visade enbart en statistisk signifikant skillnad (p <0,05) vid segmentell strain i basala segmenten i apikala projektioner mellan erfaren biomedicinsk analytiker och student 1. Konklusion: Datamaterialet är inte tillräckligt för att kunna generalisera resultatet till en större population. Det behövs fortsatta studier inom området för att dra en mer säkerställd slutsats.
Background: Echocardiography has a major role for assessment of the left ventricle. By using segmental and global longitudinal strain and strain rate both regional and global kinetics can be assessed. Segmental strain measures deformation of the myocardium as strain rate measures the velocity of the deformation. By summing the average from all segments, global longitudinal strain is obtained. Purpose: To compare heart ultrasound-based segmental and global strain and strain rate in the left ventricle. Comparisons have been made between experienced biomedical laboratory scientist and less experienced biomedical laboratory scientist’s students. Method: Quantitative study were 10 test subjects have been examined echocardiographically. Imaging and measurements were collected with Siemens Acuson SC2000. Compilation of collected measurements were made on Microsoft Excel and Microsoft Word in charts and tables. For comparison of segmental and global strain and strain rate the analysis method Related-Samples Wilcoxon Signed Rank Test were used. Result: The result shows only one statistically significant difference (p <0.05) of segmental strain in the basal segments of apical projections between experienced biomedical laboratory scientist and student 1. Conclusion: The data material is not enough to generalize the result to a larger population. Further studies are needed to draw a more secure conclusion.

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Andersson, Nyberg Sarah, et Martina Lesjak. « Jämförelse mellan ekokardiografiska metoder vid bedömning av vänsterkammarfunktion hos kvinnliga bröstcancerpatienter ». Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-26955.

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Ekokardiografi är en mycket användbar teknik som bland annat kan bedöma vänsterkammarensfunktion hos hjärtat med hjälp av ejektionsfraktion (EF) och global longitudinell strain (GLS). EF är idag den metoden som används mest vid bedömning av vänsterkammarfunktionen och beräknas enligt Simpsons biplanmetod. GLS är en ny metod som mäter myokardiets deformation och har i tidigare studier visat sig vara en känslig metod och kan upptäcka förändringar i myokardiet tidigare än EF. Vid behandling av bröstcancer kan hjärtat påverkas toxiskt och därmed genomgår denna patientgrupp regelbundna kontroller med ekokardiografi. Syftet med denna studie är att jämföra två ekokardiografiska metoder hos 20 stycken kvinnliga bröstcancerpatienter. Jämförelser har gjorts mellan EF beräknat med Simpsons biplanmetod (EFbi) och GLS samt mellan EFbi och EF beräknat från GLS (EFGLS). Detta är en kvantitativ retrospektiv studie där data insamlats mellan oktober-december 2014 på avdelningen klinisk fysiologi vid Länssjukhuset Ryhov i Jönköping. Den analysmetod som använts är McNemar´s test samt kappavärde. Resultatet av studien visar att EFbi och GLS gav en dålig överenstämmelse mellan metoderna och en rimlig överenstämmelse sågs mellan EFbi och EFGLS. Slutsatsen har dragits utifrån kappavärdet.
Echocardiography is a useful technique which can value the function of the left chamber of the heart by using ejection fraction (EF) and global longitudinal strain (GLS). Today EF is the most common method in assessments of the left chamber function and is calculated by Simpson´s biplanemethod. GLS is a new method that measures the myocardial deformation. It has been proved to be a sensitive method and can detect changes in the myocardium earlier than EF. The purpose of this study is to compare two echocardiographic methods among 20 female breast cancer patients. Comparisons have been made between EF calculated with Simpson´s biplanemethod (EFbi) and GLS, and between EFbi and EF calculated by GLS (EFGLS). This is a quantitative retrospective study. The data used in this study was collected between October – December 2014 at the Department of Clinical Physiology at the Hospital Ryhov in Jönköping. The method used to analyse the results was McNemar´s test and Kappa value. The results of the study showed that EFbi and GLS gave a modest correspondence between the methods. A reasonable correspondence were observed between EFbi and EFGLS. The conclusion has been drawn from the kappa value.

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Trivedi, Siddharth Jagdish. « Clinical utility of speckle tracking echocardiography in the assessment of cardiovascular disease ». Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/25705.

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Left ventricular (LV) ejection fraction (EF) derived from two-dimensional echocardiography has been the cornerstone for LV function assessment for more than half a century. However, EF is only an indirect measure of cardiac output obtained from changes in LV volume, and does not necessarily reflect intrinsic myocardial contractile properties. Furthermore, LVEF measurement has a number of challenges that relate to image quality, LV geometry assumptions, and technical expertise, and has significant issues with intra-observer, inter-observer, and test-retest variability. A more contemporary marker of LV systolic function is speckle tracking echocardiography (STE)-based global longitudinal strain (GLS). Based on deformation of the cardiac muscle, GLS provides a more direct evaluation of myocardial contractile function. GLS is highly sensitive for the detection of overt LV dysfunction, as well as subclinical LV systolic impairment when LVEF is still considered normal. Furthermore, longitudinal strain has great utility in the evaluation of right ventricular (RV) function, as well as atrial function. Two-dimensional GLS, derived from semiautomatic software, has a high temporal and spatial resolution and consequently, improved inter- and intra-observer reproducibility, compared to LVEF. The overall aim of this thesis was to explore the role of STE-derived GLS in a variety of cardiovascular conditions. Firstly, the utility of GLS in patients with ventricular arrhythmias was assessed, including patients with and without structural heart disease. GLS in cardio-oncology, specifically left-sided breast cancer patients undergoing radiation therapy, was also evaluated. RV strain in patients with pulmonary embolism was studied in order to identify its role in the management of these patients. Finally, left atrial function, including left atrial strain, was addressed in a population of elite athletes with and without atrial fibrillation and compared to non-athletes.

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Cañon-Montañez, Wilson. « Strain longitudinal global e síndrome metabólica no ELSA-Brasil : uma análise por ecocardiografia bidimensional speckle-tracking ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/139778.

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A presente tese de doutorado foi realizada com o objetivo de investigar a associação entre a síndrome metabólica (SM) e seus componentes com o strain longitudinal global (GLS) medido pela ecocardiografia bidimensional speckle-tracking (2D-STE) em indivíduos de meia idade (35 a 74 anos) no contexto brasileiro. O trabalho foi realizado com dados basais (2008-2010) da amostra aleatória do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil), que se trata de um estudo de coorte multicêntrico composto por 15105 homens e mulheres, servidores civis, ativos e aposentados de seis instituições de ensino superior e pesquisa brasileiras. Nesta tese, foram investigadas associações entre a SM e seus componentes com o GLS, para identificar disfunção ventricular esquerda subclínica nos participantes do ELSA-Brasil. Entre os participantes que preencheram os critérios de inclusão [53% mulheres; 52 ± 9 anos], 42% tinham SM. Os indivíduos com SM apresentaram piores valores de GLS [(-18,0 ± 2,5%) do que aqueles sem SM (-19,0 ± 2,4%), p <0,0001], e quase duas vezes a prevalência de disfunção sistólica subclínica. Na análise de regressão linear múltipla, o GLS foi associado com SM, mesmo após o ajuste para sexo, idade, raça/cor, escolaridade, centro de investigação, frequência cardíaca e fração de ejeção do ventrículo esquerdo por 2D-STE (β= 0,58; p <0,0001), mas o tamanho do efeito foi atenuado após ajuste para o índice de massa corporal (β= 0,39; p =0,004). A razão de prevalência ajustada de GLS alterado foi maior na SM em comparação com aqueles sem SM para 1.0 desvio padrão (GLS=-16,1%; RP= 1,45 [IC 95%: 1,09-1,93]) e 1.5 desvio padrão (GLS=-14,8%; RP = 1,93 [IC 95%: 1,25 - 2,99]). Em relação aos componentes da SM, a análise de regressão quantílica ajustada mostrou que a circunferência da cintura elevada foi independentemente associada com o GLS alterado (percentil 95), mesmo após o ajuste para os principais confundidores (p <0,0001). De acordo com os resultados do estudo, evidenciou-se que a SM é independentemente associada com a alteração da função sistólica do ventrículo esquerdo avaliada por GLS. Além disso, demonstrou-se que a circunferência da cintura elevada é o principal componente associado à alteração do strain miocárdico dentre os critérios atualmente propostos para o diagnóstico de SM. Os achados sugerem a presença de uma alteração precoce subclínica da contratilidade miocárdica relacionada com obesidade abdominal e SM.
The present doctoral thesis aimed to investigate the association between metabolic syndrome (MetS) and its components with global longitudinal strain (GLS) measured by two-dimensional speckle-tracking echocardiography (2D-STE) in middle-age individuals (35 to 74 years) in the Brazilian context. This investigation was carried out with baseline data (2008-2010) from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) which is a multicenter cohort study composed of 15,105 men and women, civil servants, active and retired, from universities or research institutions located in six states of Brazil. In this thesis, we investigated associations between MetS and its components with GLS to identify subclinical left ventricular dysfunction in participants from ELSA-Brasil. Among the participants who fulfilled the inclusion criteria [53% women; 52 ± 9 years], 42% had MetS. Individuals with MetS had worse GLS [(-18.0 ± 2.5%) than those without MetS (-19.0 ± 2.4%), p <0.0001], and about twice the prevalence of subclinical systolic dysfunction. In multiple linear regression analysis, GLS was associated with MetS even after adjusting for sex, age, race/color, educational level, study center, heart rate, and LV ejection fraction by 2D-STE (β= 0,58; p < 0,0001), but the effect was attenuated after adjusting for body mass index (β= 0,39; p =0,004). The adjusted prevalence ratio of altered GLS was higher in MetS compared to those without MetS for the 1.0 SD (GLS=-16.1%; PR=1.45 [95% CI: 1.09 - 1.93]) and 1.5 SD (GLS=-14.8%; PR=1.93 [95% CI: 1.25 - 2.99]) cut-offs. According to MetS components, adjusted quantile regression analysis showed that elevated waist circumference was independently associated with altered GLS (95th quantile), even after adjusting for main confounders (p < 0.0001). The results of this study showed that MetS is independently associated with left ventricular impaired systolic function by GLS. In addition, it was demonstrated that elevated waist circumference is the main component associated with impaired myocardial strain among the currently proposed criteria for diagnosis of MetS. The findings suggest the presence of an early subclinical myocardial contractility impairment related to abdominal obesity and MetS.

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Lundin-Emanuelsson, Madeleine. « Mental health problems and delinquency : A longitudinal study with six-month follow-up about depressive and anxiety symptoms and delinquent behavior among Italian early adolescents ». Thesis, Mälardalens högskola, Akademin för hälsa, vård och välfärd, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49368.

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Depressive and anxiety symptoms are common mental health problems globally. Antisocial behaviors can occur in early age and develop into delinquency. The aim of the study was to investigate longitudinally, with a six-month follow-up the association between mental health problems (i.e. depressive and anxiety symptoms) and delinquency among Italian early adolescents and if this association differs for boys and girls. A quantitative method was used with secondary data. The sample consisted of 155 Italian 12 years old adolescents. A longitudinal design with two occasions of measurement was used, which allows to follow individuals over time. The cross-sectional results showed that depressive symptoms were positively associated with delinquency in the total sample. However, no association was showed between anxiety symptoms and delinquency at the baseline. In addition, longitudinal results showed that medium/high delinquent behavior after six-month follow-up can partly be explained by depressive symptoms at baseline, but not by anxiety symptoms in the total sample. The longitudinal results also showed that increased levels of depressive symptoms and anxiety symptoms among boys increased the probability of having medium/high delinquent behavior, but not among girls. In conclusion, mental health problems can to some extent explain delinquency, especially among boys.

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Rabe, Nasim Estelle. « Prevalens av nedsättning av hjärtats vänsterkammares longitudinella funktion hos patienter med aortastenos ». Thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385706.

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Background:Left ventricular function is particularly important to investigate since it has prognostic significance in some heart diseases such as aortic stenosis. One of the relatively new methods to evaluate this is deformation analysis that can produce a measure of global longitudinal strain with speckle-tracking. Objective:The objective was to examine the possibility of measuring left ventricular longitudinal function in patients with aortic stenosis from ECG-gated computed tomography images with the new software Segment CT and investigate prevalence of its reduction. Additionally, a second objective was to evaluate the feasibility of global longitudinal strain analysis from ECG-gated computed tomography in comparison with echocardiography and ejection fraction in a subset of patients. Material and methods:This study included 97 patients with severe aortic stenosis who underwent evaluation before planned treatment with transcatheter aortic valve implantation during 2016-2017 at Uppsala Hospital. Global strain was calculated from ECG-gated computed tomography and echocardiography with dedicated software. Results:Left ventricular function measured by global strain was impaired in all patients while ejection fraction was decreased in 31 %. Mean global longitudinal strain by ECG-gated computed tomography was -6.46±3.51 % and by echocardiography -10.69±4.23 %. The mean difference between the methods was 4.23 %, which was statistically significant (p=0.02) while the correlation was good (r=0.74). Conclusions:The strain analysis of ECG-gated computed tomography images was successful in less than a half of the patients. The results of the two methods showed good correlation but not agreement, further research is thus needed with a higher number of patients.

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Jakobsson, Anton. « Prognostic value of global longitudinal strain in patients with myocardial infarction and normal LVEF ». Thesis, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-380395.

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Koschalka, Alexander. « Prognostische Relevanz der Magnetresonanztomographie-feature-tracking-quantifizierten longitudinalen Ventrikelfunktion nach Myokardinfarkt ». Doctoral thesis, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0005-12CF-E.

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Livres sur le sujet "Strain longitudinale globale"

Cameli, Matteo, Partho Sengupta et Thor Edvardsen. Deformation echocardiography. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0004.

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Echocardiographic strain imaging, also known as deformation imaging, has been developed as a means to objectively quantify regional and global myocardial function. First introduced as a post-processing feature of tissue Doppler imaging velocity converted to strain and strain rate, strain imaging has more recently also been derived from speckle tracking analysis. Tissue Doppler imaging yields velocity information from which strain and strain rate are mathematically derived whereas two-dimensional speckle tracking yields strain information from which strain rate and velocity data are derived. Data obtained from these two different techniques may not be equivalent due to limitations inherent with each technique. Speckle tracking analysis can generate longitudinal, circumferential, and radial strain measurements and left ventricular twist. Although potentially useful, these measurements are also complicated and frequently displayed as difficult-to-interpret waveforms. Strain imaging is now considered a robust research tool and has great potential to play many roles in routine clinical practice. This chapter explains the fundamental concepts of deformation imaging, the technical features of strain imaging using tissue Doppler imaging and speckle tracking, and the strengths and weaknesses of these methods.

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Moonen, Marie, Nico Van de Veire et Erwan Donal. Heart failure : risk stratification and follow-up. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0027.

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An increasing number of two- and three-dimensional echocardiographic, Doppler, and speckle imaging-derived parameters and values can be related to prognosis in heart failure with left ventricular (LV) systolic dysfunction. This chapter discusses both conventional and new indices, including their advantages and potential limitations. There is increasing evidence for the use of new indices, including three-dimensional LV ejection fraction and global longitudinal strain. The follow-up and monitoring of heart failure patients using two-dimensional transthoracic echocardiography is also discussed in this chapter, including how to estimate the LV filling pressures and quantify LV reverse remodelling.

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Galderisi, Maurizio, Juan Carlos Plana, Thor Edvardsen, Vitantonio Di Bello et Patrizio Lancellotti. Cardiac oncology. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0064.

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Cancer therapeutics may induce cardiac damage in the left and the right ventricle. Radiotherapy most frequently induces valvular damage, carotid stenosis, and coronary artery disease. Pericardial disease may be due to both chemo- and radiotherapy. The manifestations of both chemo- and radiotherapy can develop acutely but also become overt years after their performance, in particular after radiotherapy. The main cardiac damage of cancer therapeutics-related cardiac dysfunction (CTRCD) corresponds to the reduction of left ventricular (LV) systolic function. The Expert Consensus document from ASE and EACVI has defined CTRCD as a decrease in LV ejection fraction (LVEF) of greater than 10 percentage points, to a value less than 53%. The accurate calculation of LVEF at baseline and during follow-up is extremely important. The assessment of LV longitudinal function, in particular of speckle tracking-derived global longitudinal strain (GLS), can provide additional information, allowing early, subclinical detection of CTRCD. The ideal strategy could be to compare the measurements of GLS obtained during chemotherapy, with the one obtained at baseline. An integrated approach with the use of echocardiography at standardized, clinical preselected intervals with biomarker (ultrasensitive troponin) assessment prior to each chemotherapy cycle could be suggested in patients at high risk of CTRCD. Follow-up after therapy should depend on the type of chemotherapy/radiotherapy and the presence/absence of on-therapy CTRCD. Long-term follow-up should be planned after radiotherapy.

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Chapitres de livres sur le sujet "Strain longitudinale globale"

Kisslo, Joseph, Daniel Forsha, Minna Moreira Dias Romano, Fawaz Abdulaziz M. Alenezi, Kasper Emerek, Zainab Samad et Niels Risum. « Strain Basics and Global Longitudinal Strain ». Dans Echocardiography, 845–66. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-71617-6_34.

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Horowitz, John D., Thanh Ha Nguyen, Sven Y. Surikow, Gao Jing Ong, Cher-Rin Chong, Dana K. Dawson et Michael P. Frenneaux. « Signal transduction pathways initiated by catecholamines in takotsubo syndrome : focus on nitrosative stress and energetic impairment ». Dans ESC CardioMed, 1283–86. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198784906.003.0316.

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Takotsubo syndrome reflects an ‘aberrant’ response to acute catecholamine stimulation, largely but not entirely as a manifestation of increased sensitivity to β‎₂-adrenoceptor stimulation and signal transduction via Gi proteins, especially in ageing female hearts. It is now apparent that prolonged impairment of quality of life and slow recovery of echocardiographic parameters such as global longitudinal strain after episodes of takotsubo syndrome reflect ongoing myocardial inflammation and associated oedema, together with impairment of cardiac energetics on phosphorus magnetic resonance spectroscopy.

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Vijayaraghavan, G. « Diabetic Cardiomyopathy : Studies on Global Longitudinal Strain in Asymptomatic Diabetic Subjects ». Dans Cardiodiabetes Update : A Textbook of Cardiology, 263. Jaypee Brothers Medical Publishers (P) Ltd., 2018. http://dx.doi.org/10.5005/jp/books/14130_40.

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Nihoyannopoulos, Petros, et Julia Grapsa. « Pulmonary hypertension and the right ventricle ». Dans ESC CardioMed, sous la direction de Frank Flachskampf, 485–90. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198784906.003.0099.

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Due to its widespread availability, echocardiography is used as the first-line imaging modality for the assessment of right ventricular size, function, and pressures. Two-dimensional echocardiography can easily obtain valuable quantitative information about right ventricular size and function. Measurements such as the tricuspid annular plane systolic excursion, right ventricular myocardial performance index, fractional area change, tissue Doppler-derived tricuspid lateral annular systolic velocity, global longitudinal strain and strain rate, and eccentricity index are the recommended parameters to be used for the routine evaluation of right ventricular function. Three-dimensional echocardiography and three-dimensional strain have now entered the clinical arena for a more precise right ventricular assessment. Echocardiography is also important to establish the causes of secondary pulmonary hypertension (group 2) by evaluating the various left heart conditions leading to the rise of right ventricular systolic pressures. Finally, echocardiography is probably the most accurate non-invasive imaging modality for the assessment of right ventricular pressure and is therefore an ideal tool for the evaluation and screening of pulmonary hypertension.

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Voigt, Jens-Uwe. « Left ventricular function, heart failure, and resynchronization therapy ». Dans ESC CardioMed, sous la direction de Frank Flachskampf, 450–54. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198784906.003.0092.

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Left ventricular cavity size is commonly described using linear internal dimensions and volumes. Measurements are regularly reported for end-diastole and frequently also for end-systole. Indexing to body surface area allows a comparison among individuals with different body sizes. Ejection Fraction and Global Longitudinal Strain are used to measure global left ventricular function. Regional function is described semi-quantitatively per LV segment. Stress tests can reveal viable myocardium and inducible ischemia. Diastolic function assessment is complex and requires several parameters. All patients with symptoms of heart failure should be evaluated by echocardiography. Echocardiography also plays a critical role in identifying candidates for cardiac resynchronization. Specific motion and deformation patterns can identify patients where CRT may improve heart failure symptoms and lead to reverse remodelling.

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Hoffmann, Rainer, et Frank A. Flachskampf. « Evaluation of systolic LV function and LV mechanics ». Dans The ESC Textbook of Cardiovascular Imaging, sous la direction de José Luis Zamorano, Jeroen J. Bax, Juhani Knuuti, Patrizio Lancellotti, Fausto J. Pinto, Bogdan A. Popescu et Udo Sechtem, 497–506. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198849353.003.0034.

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Analysis of global and regional left ventricular (LV) function is the most frequent indication to perform echocardiography. While visual assessment based on 2D images is the basis for analysis of LV function, it may be supplemented by quantitative techniques to obtain parameters of global or regional function. 2D echocardiography tends to underestimate LV volumes compared to cardiac magnetic resonance (CMR), 3D echocardiography results in less volume underestimation and high accuracy in the analysis of ejection fraction. Visual analysis of regional function is limited by significant interobserver variability. Another approach to systolic LV function is the assessment of LV mechanics, typically by measuring global longitudinal deformation (strain) by speckle-tracking echocardiography. Alternatively, information on deformation can be obtained from CMR (currently, mostly by feature tracking). Deformation parameters detect early impairment of LV systolic function with higher sensitivity than ejection fraction. While echocardiography continues to be the first-choice modality for ejection fraction, CMR has become the gold standard for quantification of LV volumes and ejection fraction. Nuclear imaging should be applied to assess LV function only if simultaneous assessment of myocardial perfusion is requested.

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Actes de conférences sur le sujet "Strain longitudinale globale"

Fischetti, C., F. Guerra, A. Ferrarini, L. Zuliani, G. Stronati, P. Fraticelli, M. G. Danieli, A. Capucci et A. Gabrielli. « THU0401 Global longitudinal strain as early predictor of systolic dysfunction in systemic sclerosis ». Dans Annual European Congress of Rheumatology, EULAR 2018, Amsterdam, 13–16 June 2018. BMJ Publishing Group Ltd and European League Against Rheumatism, 2018. http://dx.doi.org/10.1136/annrheumdis-2018-eular.6423.

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Lui, J. K., M. Winburn, M. A. Trojanowski, A. M. Bujor, M. P. LaValley, D. M. Gopal, R. S. Wiener et E. S. Klings. « Clustering of Systemic Sclerosis-related Pulmonary Hypertension by Global Longitudinal Left Ventricular Strain ». Dans American Thoracic Society 2022 International Conference, May 13-18, 2022 - San Francisco, CA. American Thoracic Society, 2022. http://dx.doi.org/10.1164/ajrccm-conference.2022.205.1_meetingabstracts.a3604.

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Figueirôa, Maria de Lourdes Castro de Oliveira, Maria Carolina Moura Costa, Maria Clara Moura Costa Campos, Paulo Rocha Lobo, Viviane Leal Novais, Renata Borges de Lima, Izabela Prado Viana et al. « EVALUATION OF THE PREVALENCE OF SUBCLINICAL SYSTOLIC DYSFUNCTION IN TAKAYASU ARTERITIS USING GLOBAL LONGITUDINAL STRAIN ». Dans XXXIX Congresso Brasileiro de Reumatologia. Sociedade Brasileiro de Reumatologia, 2022. http://dx.doi.org/10.47660/cbr.2022.2196.

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Ayton, Sarah L., Gaurav S. Gulsin, Kelly S. Parke, Joanne V. Wormleighton, J. Ranjit Arnold, Alastair J. Moss, Anvesha Singh et al. « 22 Inter-field strength agreement of left ventricular strain and strain rate using Tissue Tracking and AI derived global longitudinal shortening ». Dans British Society of Cardiovascular Magnetic Resonance 2021 Annual Meeting. BMJ Publishing Group Ltd and British Cardiovascular Society, 2021. http://dx.doi.org/10.1136/heartjnl-2021-bscmr.22.

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Nourpanah, Nikzad, et Farid Taheri. « Finite Element Analysis of Strain Concentration in Field Joint of Concrete Coated Pipelines ». Dans ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79047.

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Realistic and accurate modeling of the strains developed in concrete coated pipelines is an important objective to offshore pipeline industry. This is because of the acceptance of the strain-based design methods and also the increasing demand on pipelines to operate under harsher environments/loading conditions. The problem has several sources of nonlinearity, namely: material plasticity, concrete cracking and crushing and concrete slippage on the steel pipe. In this paper, a framework and procedure for finite element (FE) modeling of concrete coated pipelines is presented and verified against test results available in literature. The mechanics of strain concentration at the Field Joint (FJ), where the coating has an abrupt discontinuity is described and studied via the verified FE model. These aspects are all described and modeled appropriately using the general purpose FE software ABAQUS, resulting in a realistic and accurate FE model which predicts the strain and stress distribution in the steel, concrete coating and the anticorrosion layer. Output results, presented in the form of variation of moment versus strain, longitudinal distribution of the axial strains, the maximum FJ strains, strain concentration factor as a function of global strain and relative slippage of concrete coating are reported and verified with comparison to test data. Good agreements, both in trend and also quantities are observed, thereby verifying the integrity of the framework suited for the further development, which would include a parametric study with the aim of developing practical design equations. Discussion on the circumferential distribution of shear stresses in the anticorrosion layer is also presented. FE results show a constant shear stress distributed nearly all along the circumference, in concert with the test results.

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Tajika, Hisakazu, Takahiro Sakimoto, Tsunehisa Handa, Satoshi Igi, Rinsei Ikeda et Joe Kondo. « Strain Capacity Investigation on Grade X70 High Strain Line Pipe With Girth Weld ». Dans ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-85059.

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Recently high grade pipeline project have been planned in hostile environment like landslide in mountain area, liquefaction in reclaimed land or the frost heave in Polar Regions. Geohazards bring large scale ground deformation and effect on the varied pipeline to cause large deformation. Therefore, strain capacity is important for the pipeline and strain based design is also needed to keep gas transportation project in safe. High grade steel pipe for linepipe tends to have higher yield to tensile (Y/T) ratio and it has been investigated that the lower Y/T ratio of the material improves strain capacity in buckling and tensile limit state. In onshore pipeline project, pipe usually transported in 12 or 18m each and jointed in the field. Girth weld (GW) is indispensable so strength matching of girth weld towards pipe body is important. In this study strain capacity of Grade X70 high strain pipe with size of 36” OD and 23mm WT was investigated with two types of experiments. One was a pipe bending test with whole pipe. The length of the specimen was approximately 8m and GW was made in the middle of joint length. A fixed internal pressure was applied during the bending test. Actual pipe situation in work was simulated and both circumferential and longitudinal stress occurred in this test. The other test was curved wide plate (CWP) test. In both tests, test pipes were cut and welded using GTAW in the first two layers and GMAW for the subsequent passes. Welding wire of TG-S62 and MG-S58P were used for GTAW and GMAW respectively to achieve over-matching girth weld considering the pipe body strength. Elliptical EDM notch was installed in the GW HAZ as simulated weld defect. In pipe bending test, buckling occurred at the intrados at 300 mm apart from the GW. 2D average compressive strain at buckling was 3.59% and this high compressive strain was considered to derive from the high strain capacity of this pipes. After the buckling, deformation concentrated to the buckling wrinkle. Test pipe broke at 35.5 degrees of pipe end rotation and the location was in base metal at the extrados opposite to the buckling wrinkle. The HAZ notch opened and CTOD was 1.44 mm and the global strain in 2D length average strain was 7.8%. In CWP test, tensile strain simply got large and pipe finally broke at global strain of 9.6% and CTOD of 15 mm. The break location was the HAZ notch. There was a significant difference in CTOD growth in HAZ between two test types. Conditions and factors that effect to these differences are argued in this paper.

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Lavery, R., C. Vaughan, C. O’Herlihy, A. Amaro, M. Hinds et DM Kerins. « 59 An investigation of global longitudinal strain in primary mitral regurgitation : a retrospective cohort of patients with mitral regurgitation ». Dans Irish Cardiac Society Annual Scientific Meeting & AGM, Thursday October 4th – Saturday October 6th 2018, Galway Bay Hotel, Galway, Ireland. BMJ Publishing Group Ltd and British Cardiovascular Society, 2018. http://dx.doi.org/10.1136/heartjnl-2018-ics.59.

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Chee, Jayden, Alastair Walker et David White. « Effect of Lateral Pipe-Soil Interaction on Controlled Lateral Buckling Using Pre-Deformed Pipeline ». Dans ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77154.

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A novel approach to eliminate the onset of global buckling in pipelines is investigated in the paper. The method is based on pre-deforming a pipeline continuously with a specific wavelength and amplitude prior to installation on the seabed. The response of the pipeline to applied high temperature and pressure was studied in conjunction with variations in the lateral pipe-soil interaction (PSI) — both as uniform friction along the pipe and also with locally varying friction. Pipe and seabed parameters representing a typical wet-insulated infield flow line on soft clay are used. The pre-deformed pipeline has a higher buckle initiation temperature compared to a straight pipeline due to the reduced effective axial force build-up resulting from the low axial stiffness generated by the pre-deformed lobes along the pipeline. The results from this paper show that the strains in the pre-deformed pipeline are not significantly affected by the local variability of lateral PSI but rather by the global mean PSI. At a typical lateral soil resistance, i.e. a friction coefficient of 0.5, lateral buckling occurs at a very high temperature level that is not common in the subsea operation. At a very low friction, i.e. 0.1, lateral buckling occurs at a lower operating temperature but the strain is insignificant. The longitudinal strain of the pipeline is not highly sensitive to the lateral PSI, which is a quite different response to an initially straight pipeline. Therefore, this method could prove to be a valuable tool for the subsea industry as it enables the pipeline to be installed and operated safely at very high temperatures without the need for lateral buckling design and installation of expensive structures as buckle initiators. Even if the pre-deformed pipeline buckles at a very high temperature, during cycles of heat-up and cool-down the buckle shape ‘shakes down’ by geometric rearrangement to minimize the energy, and in doing so creates a series of ‘short pipelines’ in which the longitudinal strain is self-controlled. The system is therefore shown to be very robust in the conditions investigated and not affected by one of the biggest unknowns in seabed pipeline engineering, which is the local variability in lateral PSI.

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Klester, Elena, Karolina Klester, Yakov Shoykhet, Alexandra Balitskya, Valentina Yarkova et Viktor Nikitin. « Comparative analysis of global longitudinal strain in patients with ST-segment elevation myocardial infarction (STEMI) with and without concomitant COPD ». Dans ERS International Congress 2019 abstracts. European Respiratory Society, 2019. http://dx.doi.org/10.1183/13993003.congress-2019.pa2662.

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Torselletti, Enrico, Luigino Vitali, Roberto Bruschi, Erik Levold et Leif Collberg. « Submarine Pipeline Installation Joint Industry Project : Global Response Analysis of Pipelines During S-Laying ». Dans 25th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/omae2006-92377.

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The development of deep water gas fields using trunklines to carry the gas to the markets is sometime limited by the feasibility/economics of the construction phase. In particular there is market for using S-lay vessel in water depth larger than 1000m. The S-lay feasibility depends on the applicable tension at the tensioner which is a function of water depth, stinger length and stinger curvature (for given stinger length by its curvature). This means that, without major vessel up-grading and to avoid too long stingers that are prone to damages caused by environmental loads, the application of larger stinger curvatures than allowed by current regulations/state of the art, is needed. The work presented in this paper is a result of the project “Development of a Design Guideline for Submarine Pipeline Installation” sponsored by STATOIL and HYDRO. The technical activities are performed in co-operation by DNV, STATOIL and SNAMPROGETTI. This paper presents the results of the analysed S-lay scenarios in relation to extended laying ability of medium to large diameter pipelines in order to define the statistical distribution of the relevant load effects, i.e. bending moment and longitudinal strain as per static/functional, dynamic/total, and environmental load effects. The results show that load effects (longitudinal applied strain and bending moment) are strongly influenced by the static setting (applied stinger curvature and axial force at the tensioner in combination with local roller reaction over the stinger). The load effect distributions are the basis for the development of design criteria/safety factors which fulfil a predefined target safety level.

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Rapports d'organisations sur le sujet "Strain longitudinale globale"

Rogers, Jessa, Kate E. Williams, Kristin R. Laurens, Donna Berthelsen, Emma Carpendale, Laura Bentley et Elizabeth Briant. Footprints in Time : Longitudinal Study of Indigenous Children. Queensland University of Technology, octobre 2022. http://dx.doi.org/10.5204/rep.eprints.235509.

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The Longitudinal Study of Indigenous Children (LSIC; also called Footprints in Time) is the only longitudinal study of developmental outcomes for Aboriginal and Torres Strait Islander children globally. Footprints in Time follows the development of Australian Aboriginal and Torres Strait Islander children to understand what Indigenous children need to grow up strong. LSIC involves annual waves of data collection (commenced in 2008) and follows approximately 1,700 Aboriginal and Torres Strait Islander children living in urban, regional, and remote locations. This LSIC Primary School report has been produced following the release of the twelfth wave of data collection, with the majority of LSIC children having completed primary school (Preparatory [aged ~5 years] to Year 6 [aged ~12 years]). Primary schools play a central role in supporting student learning, wellbeing, and connectedness, and the Footprints in Time study provides a platform for centring Indigenous voices, connecting stories, and exploring emerging themes related to the experience of Indigenous children and families in the Australian education system. This report uses a mixed-methods approach, analysing both quantitative and qualitative data shared by LSIC participants, to explore primary school experiences from the perspective of children, parents and teachers. Analyses are framed using a strengths-based approach and are underpinned by the understanding that all aspects of life are related. The report documents a range of topics including teacher cultural competence, racism, school-based Aboriginal and Torres Strait Islander education activities, parental involvement, engagement, attendance, and academic achievement.

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