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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Rastreamento de disfunção ventricular assintomática em puérperas : padrão ecocardiográfico evolutivo e comparativo a casos de miocardiopatia periparto

Vettori, Daniela Vanessa January 2008 (has links)
Objetivos: Determinar a prevalência de disfunção sistólica assintomática do ventrículo esquerdo no puerpério e comparar sua evolução com os casos de miocardiopatia periparto ocorridos no mesmo período. Pacientes e Métodos: Estudo transversal entre setembro de 2002 e abril de 2005, para determinar a prevalência de disfunção ventricular assintomática no puerpério imediato e a incidência de miocardiopatia periparto no mesmo período, e entre novembro de 2007 e janeiro de 2008 para verificar a evolução clínica e ecocardiográfica destas pacientes. Os parâmetros ecocardiográficos das puérperas com disfunção ventricular assintomática também foram comparados com os de puérperas normais. Disfunção sistólica do ventrículo esquerdo foi definida como diâmetro diastólico final ≥ 5,6 cm e/ou fração de ejeção < 53,0% + encurtamento fracional sistólico < 25%. Resultados: Foram rastreadas 1182 puérperas, sendo detectados 10 casos (0,85%) de disfunção ventricular assintomática, cujas características clínicas, como raça, superfície corporal, paridade, gemelaridade e uso de tocolíticos, não foram diferentes quando comparadas com 18 controles rastreados sem disfunção. A incidência de miocardiopatia periparto no período foi de 6 casos em 10866 partos (1/1811 partos de nascidos vivos). Após uma média de 4,0 anos (2,9-5,2 anos), 7 dos 10 casos de disfunção assintomática e 5 dos 6 casos de miocardiopatia clínica realizaram nova ecocardiografia, verificando-se significativo aumento da fração de ejeção e do encurtamento fracional médios nos dois grupos, sendo que a parcela de recuperação da função foi semelhante nos grupos (p interação > 0,05). Conclusões: Ocorre disfunção ventricular no puerpério sem os achados clínicos de insuficiência cardíaca cujos parâmetros ecocardiográficos evoluem de maneira semelhante aqueles de pacientes com miocardiopatia periparto ao longo do tempo. / Objective: To determine the prevalence of asymptomatic left ventricular systolic dysfunction in puerperium and to compare its progression with that of cases of peripartum cardiomyopathy that occurred in the same study period. Patients and Methods: Cross-sectional study conducted from September 2002 to April 2005 to determine the prevalence of asymptomatic ventricular dysfunction in early puerperium and the incidence of peripartum myocardiopathy, and from November 2007 to January 2008 to obtain clinical and echocardiographic follow-up data of the study patients. Echocardiographic parameters of puerperal women with asymptomatic ventricular dysfunction were also compared with those of normal puerperal women. The parameters to define left ventricular systolic dysfunction were end-diastolic diameter ≥ 5.6 cm and/or ejection fraction < 53.0%, and systolic fractional shortening < 25%. Results: A total of 1182 puerperal women were screened, and 10 cases (0.85%) of asymptomatic ventricular dysfunction were detected. Clinical characteristics, such as ethnicity, body surface, parity, multiple gestations, and tocolytic therapy, were not different from those of the 18 normal women used as controls. The incidence of peripartum cardiomyopathy was 6 cases out of 10866 deliveries (1/1811 live births). After a mean of 4.0 years (2.9-5.2 years), 7 of the 10 patients with asymptomatic dysfunction and 5 of the 6 with clinical cardiomyopathy underwent follow-up echocardiography. A significant increase was found in mean ejection fraction and fractional shortening in the two groups, and function recovery rates were similar in the two groups (p > 0.05). Conclusions: Ventricular dysfunction may occur in the puerperium without clinical signs of heart failure, and the long-term progression of echocardiographic parameters is similar to that found in cases of peripartum cardiomyopathy.
82

Rastreamento de disfunção ventricular assintomática em puérperas : padrão ecocardiográfico evolutivo e comparativo a casos de miocardiopatia periparto

Vettori, Daniela Vanessa January 2008 (has links)
Objetivos: Determinar a prevalência de disfunção sistólica assintomática do ventrículo esquerdo no puerpério e comparar sua evolução com os casos de miocardiopatia periparto ocorridos no mesmo período. Pacientes e Métodos: Estudo transversal entre setembro de 2002 e abril de 2005, para determinar a prevalência de disfunção ventricular assintomática no puerpério imediato e a incidência de miocardiopatia periparto no mesmo período, e entre novembro de 2007 e janeiro de 2008 para verificar a evolução clínica e ecocardiográfica destas pacientes. Os parâmetros ecocardiográficos das puérperas com disfunção ventricular assintomática também foram comparados com os de puérperas normais. Disfunção sistólica do ventrículo esquerdo foi definida como diâmetro diastólico final ≥ 5,6 cm e/ou fração de ejeção < 53,0% + encurtamento fracional sistólico < 25%. Resultados: Foram rastreadas 1182 puérperas, sendo detectados 10 casos (0,85%) de disfunção ventricular assintomática, cujas características clínicas, como raça, superfície corporal, paridade, gemelaridade e uso de tocolíticos, não foram diferentes quando comparadas com 18 controles rastreados sem disfunção. A incidência de miocardiopatia periparto no período foi de 6 casos em 10866 partos (1/1811 partos de nascidos vivos). Após uma média de 4,0 anos (2,9-5,2 anos), 7 dos 10 casos de disfunção assintomática e 5 dos 6 casos de miocardiopatia clínica realizaram nova ecocardiografia, verificando-se significativo aumento da fração de ejeção e do encurtamento fracional médios nos dois grupos, sendo que a parcela de recuperação da função foi semelhante nos grupos (p interação > 0,05). Conclusões: Ocorre disfunção ventricular no puerpério sem os achados clínicos de insuficiência cardíaca cujos parâmetros ecocardiográficos evoluem de maneira semelhante aqueles de pacientes com miocardiopatia periparto ao longo do tempo. / Objective: To determine the prevalence of asymptomatic left ventricular systolic dysfunction in puerperium and to compare its progression with that of cases of peripartum cardiomyopathy that occurred in the same study period. Patients and Methods: Cross-sectional study conducted from September 2002 to April 2005 to determine the prevalence of asymptomatic ventricular dysfunction in early puerperium and the incidence of peripartum myocardiopathy, and from November 2007 to January 2008 to obtain clinical and echocardiographic follow-up data of the study patients. Echocardiographic parameters of puerperal women with asymptomatic ventricular dysfunction were also compared with those of normal puerperal women. The parameters to define left ventricular systolic dysfunction were end-diastolic diameter ≥ 5.6 cm and/or ejection fraction < 53.0%, and systolic fractional shortening < 25%. Results: A total of 1182 puerperal women were screened, and 10 cases (0.85%) of asymptomatic ventricular dysfunction were detected. Clinical characteristics, such as ethnicity, body surface, parity, multiple gestations, and tocolytic therapy, were not different from those of the 18 normal women used as controls. The incidence of peripartum cardiomyopathy was 6 cases out of 10866 deliveries (1/1811 live births). After a mean of 4.0 years (2.9-5.2 years), 7 of the 10 patients with asymptomatic dysfunction and 5 of the 6 with clinical cardiomyopathy underwent follow-up echocardiography. A significant increase was found in mean ejection fraction and fractional shortening in the two groups, and function recovery rates were similar in the two groups (p > 0.05). Conclusions: Ventricular dysfunction may occur in the puerperium without clinical signs of heart failure, and the long-term progression of echocardiographic parameters is similar to that found in cases of peripartum cardiomyopathy.
83

Analyse échocardiographique des déformations myocardiques en speckle tracking / Myocardial deformations analysis by speckle tracking echocardiography

Réant, Patricia 15 December 2009 (has links)
L’analyse de la fonction systolique en échocardiographie représente un challenge majeur depuis une vingtaine d’années dans le but d’améliorer la détection et la quantification des anomalies de la contraction myocardique. L’analyse des déformations myocardiques consiste à étudier le pourcentage d’étirement ou de raccourcissement myocardiques au cours du cycle cardiaque. Après le grand pas en avant dans ce domaine, consécutif à l’avènement du Doppler tissulaire il y a un quinzaine d’années, ces 4 dernières années ont vu naître une nouvelle technique d’analyse bidimensionnelle des déformations, porteuse de grands espoirs car s’affranchissant de la limitation liée à l’angle d’incidence Doppler et basée sur le suivi des marqueurs acoustiques de la paroi myocardique : le « speckle tracking echocardiography » ou « 2D strain ». Cette thèse rapporte tout d’abord une série de travaux orientés sur la validation de ce nouvel outil. Nous avons ensuite appliqué expérimentalement cette technique pour évaluer sa capacité à détecter l’ischémie myocardique lors d’un examen de stress sous dobutamine en comparaison à l’analyse de perfusion myocardique en échographie de contraste. Enfin, nous exposons plusieurs expériences cliniques qui témoignent de quelques applications potentielles de cette technique dans la prise en charge des patients porteurs de cardiopathies diverses : myocardiopathie hypertrophique, fibrillation auriculaire paroxystique et recherche de viabilité sous faibles doses de dobutamine chez les patients porteurs d’une cardiopathie ischémique. / For 20 years, analysis of systolic myocardial function by echocardiography is a major challenge to improve the detection and the quantification of myocardial contractility abnormalities. The principle of myocardial deformation analysis consists in evaluating the percentage of myocardial thickening or shortening during the cardiac cycle. After a big step forward with the advent of tissue Doppler imaging for 15 years, the 4 last years have seen the apparition of a new technique of bidimensional analysis, without angle dependency, based on the tracking of the acoustic markers of the myocardial wall, and called « speckle tracking echocardiography » or « 2D strain ». This thesis reports serial studies oriented on the validation of this new tool and on the experimental application of this technique in the detection of myocardial ischemia during pharmacological dobutamine stress echocardiography, in comparison with myocardial perfusion analysis by contrast echocardiography. Finally, we report some clinical experiences using the speckle tracking echocardiography which attest of some clinical potential applications of this technique in the management of the patients with different cardiomyopathies: hypertrophic cardiomyopathy, lone paroxysmal atrial fibrillation, and analysis of myocardial regional deformation during low doses dobutamine infusion to investigate viability in patients with ischemic cardiomyopathy.
84

Hardware Consolidation Of Systolic Algorithms On A Coarse Grained Runtime Reconfigurable Architecture

Biswas, Prasenjit 07 1900 (has links) (PDF)
Application domains such as Bio-informatics, DSP, Structural Biology, Fluid Dynamics, high resolution direction finding, state estimation, adaptive noise cancellation etc. demand high performance computing solutions for their simulation environments. The core computations of these applications are in Numerical Linear Algebra (NLA) kernels. Direct solvers are predominantly required in the domains like DSP, estimation algorithms like Kalman Filter etc, where the matrices on which operations need to be performed are either small or medium sized, but dense. Faddeev's Algorithm is often used for solving dense linear system of equations. Modified Faddeev's algorithm (MFA) is a general algorithm on which LU decomposition, QR factorization or SVD of matrices can be realized. MFA has the good property of realizing a host of matrix operations by computing the Schur complements on four blocked matrices, thereby reducing the overall computation requirements. We will use MFA as a representative Direct Solver in this work. We further discuss Given's rotation based QR algorithm for Decomposition of any matrix, often used to solve the linear least square problem. Systolic Array Architectures are widely accepted ASIC solutions for NLA algorithms. But the \can of worms" associated with this traditional solution spawns the need for alternative solutions. While popular custom hardware solution in form of systolic arrays can deliver high performance, but because of their rigid structure they are not scalable and reconfigurable, and hence not commercially viable. We show how a Reconfigurable computing platform can serve to contain the \can of worms". REDEFINE, a coarse grained runtime reconfigurable architecture has been used for systolic actualization of NLA kernels. We elaborate upon streaming NLA-specific enhancements to REDEFINE in order to meet expected performance goals. We explore the need for an algorithm aware custom compilation framework. We bring about a proposition to realize Faddeev's Algorithm on REDEFINE. We show that REDEFINE performs several times faster than traditional GPPs. Further we direct our interest to QR Decomposition to be the next NLA kernel as it ensures better stability than LU and other decompositions. We use QR Decomposition as a case study to explore the design space of the proposed solution on REDEFINE. We also investigate the architectural details of the Custom Functional Units (CFU) for these NLA kernels. We determine the right size of the sub-array in accordance with the optimal pipeline depth of the core execution units and the number of such units to be used per sub-array. The framework used to realize QR Decomposition can be generalized for the realization of other algorithms dealing with decompositions like LU, Faddeev's Algorithm, Gauss-Jordon etc with different CFU definitions .
85

Analyse et traitement des signaux oscillomètriques pour la mesure de la pression artérielle systolique et la détermination des caractéristiques biomécaniques de la paroi artérielle. / Analysis and processing of oscillometric signals for the measurement of systolic arterial blood pressure and assessment of arterial wall biomechanics.

Benmira, Amir Mokhfi 04 July 2016 (has links)
Notre travail de thèse est consacré au développement d’une nouvelle approche d’analyse du signal oscillométrique pour mesurer la pression artérielle systolique et identifier les personnes dont la paroi artérielle est anormalement rigide. L’oscillométrie, largement exploitée pour la mesure automatique non-vulnérante de la pression artérielle, repose sur l’amplitude des variations dynamiques de pression du brassard pneumatique générées par l’expansion de l’artère brachiale sous l’effet de l’onde de pouls. Nous avons d’abord effectué une revue de la littérature sur les méthodes auscultatoire et oscillométrique. La méthode auscultatoire, fondée sur la détection des bruits produits par l’artère brachiale sous le brassard, reste la référence pour la validation des moniteurs oscillométriques. Depuis la description de ces bruits par Nicolaï Korotkoff en 1905, de nombreux auteurs ont tenté d’en expliquer l’origine et d’en identifier les limites et pièges en comparaison avec la mesure intra-artérielle directe. La technique oscillométrique dérive de l’invention du sphygmographe par Etienne-Jules Marey en 1859. Les constructeurs procèdent à la validation de leurs appareils en référence aux normes internationales (ISO) sans dévoiler les algorithmes mise en œuvre. De très nombreuses approches ont été proposées, depuis des rapports déterminés empiriquement jusqu’à des réseaux de neurones en passant par divers modèles mathématiques, pour déterminer les pressions systolique et diastolique à partir de la pression moyenne mesurée sur la courbe oscillométrique. Cependant, l’oscillométrie donne des résultats variables et présente des erreurs significatives, en particulier pour la détermination de la pression systolique, notamment chez les sujets ayant des facteurs de risque cardiovasculaires.Sur la base de cette analyse, considérant que la référence reste la détection des bruits de Korotkoff, nous avons cherché à en mieux comprendre les mécanismes. Nous avons enregistré les images échographiques et le signal Doppler de l’artère brachiale sous le brassard lors de la mesure de pression artérielle chez des sujets volontaires, en synchronisation avec l’ECG, la pression du brassard et les bruits de Korotkoff. Nous avons pu observer les variations cycliques du diamètre de l’artère brachiale pendant le dégonflage du brassard, et mesurer la vitesse locale de propagation de l’onde de pouls, ainsi que les délais entre le signal oscillométrique, l’ECG et les bruits de Korotkoff. Nous avons pu ainsi démontrer que les bruits de Korotkoff sont produits par la vibration de la paroi artérielle sous l’impact de l’onde de pouls, puis par la turbulence de l’écoulement flux sanguin, et nous avons montré la diminution marquée de la vitesse locale de l’onde de pouls lorsque la pression du brassard réduit la pression artérielle transmurale. L’observation de ces enregistrements nous a montré l’intérêt de l’analyse de la forme de l’onde de pouls enregistrée par oscillométrie. Nous en avons tiré une approche innovante fondée sur l’analyse temporelle pour la détermination directe de la pression artérielle systolique. Nous avons réalisé une étude clinique prospective, selon un protocole approuvé par le Comité d’éthique du CHU de Nîmes, pour valider notre nouvelle approche. Nous avons comparé notre technique à la méthode auscultatoire chez 145 sujets avec ou sans facteurs de risque cardiovasculaire, et à la pression mesurée par cathéter radial chez 35 patients hospitalisés en réanimation. Nous avons obtenu une excellente concordance avec le premier bruit de Korotkoff, avec des résultats très supérieurs à l’oscillométrie réalisée à l’aide d’un appareil validé. De plus, notre technique s’est montrée capable d’identifier les sujets porteurs de facteurs de risque cardiovasculaires, se comparant favorablement à la vitesse de l’onde de pouls aortique. / Our thesis is devoted to the development of a new oscillometric signal analysis approach to measure systolic blood pressure and identify subjects with abnormal arterial wall rigidity. Oscillometry, widely used for the non-invasive automatic measurement of blood pressure, is based on the amplitude of the dynamic cuff-pressure oscillations generated by the expansion of the brachial artery at the arrival of the pulse wave.We first conducted a literature review on the auscultatory and oscillometric methods. The auscultatory method, based on the detection of the sounds emitted by the brachial artery under the cuff, remains the reference for the validation of oscillometric monitors. Since the description of these sounds by Nicolai Korotkoff in 1905, many authors attempted to explain their origin and assess their limits and pitfalls in comparison with direct intra-arterial blood pressure measurement.Oscillometric technique derive from the sphygmograph built by Etienne-Jules Marey in 1859. Manufacturers validate their oscillometric devices in reference to the international standards (ISO) without revealing the algorithms they use. Numerous approaches have been proposed, from fixed empirical ratios to neural networks to various mathematical models, for the calculation of systolic and diastolic pressure since only the mean arterial pressure is actually measured on the oscillometric curve. However, oscillometry yields variable results and produces significant errors, especially for systolic pressure, notably in patients with cardiovascular risk factors.Based on this analysis, and considering that the reference remains the detection of Korotkoff sounds, we sought to better understand their mechanisms. We recorded ultrasound images and the Doppler signal of the brachial artery under the cuff when measuring blood pressure in volunteers, simultaneously with ECG, cuff pressure and Korotkoff sounds. We could record the systolic diameter changes of the brachial artery during cuff deflation, and measure the local pulse wave velocity, as well as the time delay between the oscillometric signal, the ECG and the Korotkoff sounds. We were able to demonstrate that the Korotkoff sounds are produced by arterial wall vibration under the impact of the pulse wave, then by blood flow turbulence, and we measured the marked decrease in local pulse wave velocity when the cuff inflation reduces the brachial artery transmural pressure.We concluded to the interest of pulse waveform analysis, and designed an innovative approach based on its temporal characteristics for the direct determination of systolic blood pressure. We conducted a prospective clinical study, according to a protocol approved by the Ethics Committee of the Nîmes University Hospital Center, to validate our new approach. We compared our technique to the auscultation method in 145 subjects with or without cardiovascular risk factors, and to direct blood pressure measurement with a radial catheter in 35 patients hospitalized in the intensive care unit. We obtained an excellent correlation with the first Korotkoff sound, with better results than conventional oscillometry. In addition, our technique has proven able to identify subjects with cardiovascular risk factors with an accuracy favorably comparable to aortic pulse wave velocity.
86

Analýza surogát pro určení významnosti interakce mezi kardiovaskulárními signály / Surrogate data analysis for assessing the significance of interaction between cardiovascular signals

Javorčeková, Lenka January 2019 (has links)
The aim of this diploma thesis was to get familiar with methods to generate surrogates and how to apply them on cardiovascular signals. The first part of this diploma thesis describes the basic theory of baroreflex function and methods to generate surrogate data. Surrogate data were generated from data, acquired from the database, by using three different methods. In the next part of this diploma thesis, coherence significance between blood pressure and heart intervals was calculated by using surrogates. In the end two hypotheses were defined and tested by which it was detected whether the orthostatic change of the measurement position has effect on the causal coherence change and baroreflex function.
87

Analyzátor průběhů srdečního rytmu / Analyzer of cardiac waveform

Zmeškal, Ladislav January 2015 (has links)
The thesis describes design, algorithmization and realization of graphical application for recording EKG and PPG signal using LabJack UE9 tool in Matlab program, it also describes subsequent deposition of recorded signals and their processing, such as optional selection, cropping and filtering. Furthermore there are described types of filters, methods for detecting basic parameters of EKG and PPG signals and methods for detecting R waves and Systolic peaks. Based on detection of those parameters, algorithms for computing average heart rate and finding arrhythmias were designed and tested. Last part of the thesis includes an evaulation which compares values detected by designed algorithms with values from public database which includes reference annotation.
88

Hur kroppspositionen påverkar blodtrycket i arteria brachialis : Jämförelse mellan oscillometrisk och auskultatorisk mätmetod / How the body position affects the blood pressure in arteria brachialis

Benyamin, Juliana, Nisan, Ata January 2022 (has links)
Blodtrycksmätning är en viktig hälsokontroll hos vuxna. Tidigare har auskultatoriska blodtrycksmätningen varit den vanligaste metoden men på senare tid har den oscillometriska metoden ofta ersatt den auskultatoriska metoden. Blodtrycksmätning är viktigt för att upptäcka hypertoni. Blodtrycksmätningen sker i olika positioner i olika verksamheter. Syftet med denna studie är att undersöka hur liggande, sittande och stående kroppsposition påverkar blodtrycket samt jämföra auskultatorisk och oscillometrisk mätmetod. En kvantitativ studie utfördes där 50 försökspersoner mellan 18–45 års ålder undersöktes. Vid jämförelse av kroppspositionerna med oscillometrisk metod visades en statistiskt signifikant skillnad mellan alla positioner med avseende på de diastoliska värdena. Däremot förekom det endast en signifikant skillnad vid jämförelse av liggande och stående position, med avseende på de systoliska värdena. Vid den auskultatoriska mätningen visades en statistisk signifikant skillnad mellan alla positioner förutom systoliskt tryck i sittande och stående positionen med ett p-värde= 0,808. En statistisk signifikant skillnad visades mellan den oscillometriska och auskultatoriska mätmetoden i de diastoliska värdena, p-värde= &lt;0.001. Det förekommer en statistisk signifikant skillnad mellan mätvärdena vid jämförelse av kroppspositionerna, blodtrycket ökades från liggande, sittande till stående position. Den oscillometriska mätmetoden visade ett högre medelvärde på blodtrycksmätvärdena än med den auskultatoriska metoden, förutom det diastoliska trycket i liggande position.
89

GRAD AV FÖRÄNDRING AV TRYCKGRADIENT HOS TRIKUSPIDALISINSUFFICIENS EFTER LÄTTARE FYSISK ANSTRÄNGNING

Fornell, Ellinor January 2018 (has links)
Klaffvitier är några av de vanligaste hjärtsjukdomarna och studier visar att fysisk aktivitet är en viktig del av den kliniska diagnostiken speciellt för individer med symtomfri problematik. Fysisk aktivitet leder hos en del individer till typiska symtom för klaffvitium och ger således möjlighet till förbättrad gradering av klaffvitier jämfört med i vila. Syftet med studien är att ekokardiografiskt studera eventuell förändring av trikuspidalisklaffunktion i vila och efter lättare fysisk ansträngning, samt undersöka hypotesen om trikuspidalisinsufficiens samt tryckgradienten över trikuspidalisklaffen förändras i samband med denna typ av diagnostik. Sexton deltagare inkluderas vid anamnes på andfåddhet eller ansträngningsutlösta hjärtbesvär samt även fynd av trikuspidalisinsufficiens i samband med ordinarie undersökningstillfälle. Även de med känd trikuspidalis-insufficiens sedan tidigare inkluderades. Efter ordinarie ekokardiografisk undersökning som individerna var remitterade till fick inkluderade deltagare utföra ett cykeltest på ergometercykel under sex minuter med en lättare belastning. Ultraljudsbilder på hjärtat samlades in direkt efter avslutad ansträngning. Två variabler, tryckgradient före respektive efter ansträngning över trikuspidalisklaffen, analyserades enligt dess differens och därefter analyserades differenserna i förhållande till nollhypotesen. Medianvärden av variablerna jämfördes i Wilcoxons teckenrangtest och med Spearmans rangkorrelation studerades förhållandet mellan stigande hjärtfrekvens samt tryckgradient vid fysisk ansträngning. Studien visade att tryckgradienten hos trikuspidalis-insufficiensen förändrades vid utförande av lättare fysisk ansträngning hos individer med ansträngningsutlösta hjärtbesvär samt att denna form av undersökning i anslutning till ordinarie undersökningstillfälle kan vara av värde bland individer med anamnes på ansträngningsutlösta hjärtbesvär. / Valvular heart disease are one of the most common heart diseases and previous studies have shown that exercise is an important part of the clinical diagnostics, especially in asymphtomatic individuals. In some cases, exercise lead to typical symptoms of valvular heart disease and improved grading compared to rest. The aim of the present study was to analyze tricuspid valvular function in rest compared to exercise and examine whether or not tricuspid regurgitation and pressure gradient over the tricuspid valve will alter after exercise. Sixteen participants was included with anamnesis of dyspnea or cardiac symptoms related to exercise as well as findings of tricuspid regurgitation during the echocardio-graphic examination. Individuals with known tricuspid regurgitation were also included. After the transthoracic echocardiographic examination, included individuals performed a bicycle test for six minutes with light workload. Additional ultrasound images of the heart was collected immediately after finished bicycle test. Two variables, pressure gradient over the tricuspid valve before and after right exercise, were analyzed according to its difference and then the differences were analyzed relative to the zero hypothesis. Median values of the variables were compared in Wilcoxon's signed-rank test and Spearman's rank correlation analyzed the relationship between increasing heart rate and pressure gradient under the influence of exercise. This study has shown that the pressure gradient of the tricuspid regurgitation changes in the performance of light exercise in individuals with history of dyspnea or cardiac symptoms related to exercise. It also showed the value of an exercise test in adherence to the echocardiographic examination in this group of individuals.
90

Sambandet mellan TAPSE och RVs´ vid bedömning av RV:s funktion med ekokardiografi hos hjärtfriska individer : En jämförande studie / The relationship between TAPSE and RVs' when assessing RV function with echocardiography in heart healthy individuals : A comparative study

Wafaa, Hamsho, Hosseinzadeh, Sousan January 2023 (has links)
Högerkammare (RV) har en komplex anatomi, spelar en viktig roll för blodsyresättning och kan påverkas av fler patofysiologiska tillstånd. Utvärdering av RV:s funktion är viktig för överlevnad och har prognostiskt värde vid hjärt-och lungsjukdomar. Transthorakal ekokardiografi (TTE) används för RV:s storlek- och funktionsbedömning. Tricuspid annular plane systolic excursion (TAPSE) och annulus tricuspid peak systolic velocity (RVs´) är två vanliga metoder för bedömning av RV:s funktion. Båda metoderna har bra reproducerbarhet och är enkla att utföra.  Syftet med detta arbete är att utreda interobservatörvariation, sambandet och överensstämmelse mellan TAPSE och RVs´. Studien är en tvärsnittsstudie av 53 friska testpersoner 18-60 åringar. Mätningen baserades på en blind dubbelbestämning av två biomedicinska analytiker studenter. Analysen genomfördes med programmet IBM SPSS Statistics.  Interobservatörvariationsanalys visade ingen signifikant skillnad i mätosäkerheten mellan studenterna, (PTAPSE=0,568 och PRVs´=0,548). Enligt regressionsanalysen hade RVs´ något mindre mätosäkerhet än TAPSE. Ett svagt positivt samband hittades mellan RVs´ och TAPSE och 100% överenstämmelse avseende utfall påvisades, Kappavärdet blev 1. Båda metoderna har bra interobservatörvariation hos oerfarna undersökare. Hos hjärt- och lungfriska ser sambandet svagt positivt ut mellan TAPSE och RVs´. Dock kunde tidigare studier identifiera starkare positivt samband. Skillnaden i resultatet kan bero på erfarenhetsbrist hos studenterna och lågt antal deltagare. / The Right ventricle (RV) has a complex anatomy, plays an important role in blood oxygenation and can be affected by several pathophysiological conditions. Evaluation of RV function has prognostic value in heart and lung diseases. Tricuspid annular plane systolic excursion (TAPSE) and annulus tricuspid peak systolic velocity (RVs´) are two common methods for assessing RV function in Transthoracic echocardiography.  The study aimed to investigate interobserver variation, the correlation and agreement between TAPSE and RVs´. The study is a cross-sectional study of 53 healthy participants aged 18-60. The measurement was based on a blind double determination by two biomedical analyst students. The analysis was implemented with the program IBM SPSS Statistics. Interobserver variation analysis showed no significant difference between the two students, (PTAPSE =0,568 and PRVs´=0,548). Regression analysis showed RVs´ had slightly less measurement uncertainty than TAPSE. A weak positive correlation was found between RVs´ and TAPSE and 100% agreement regarding outcome was demonstrated, Kappa value was 1. Both methods have good interobserver variation in inexperienced examiners. In people with healthy heart and lungs, the relationship between TAPSE and RVs looks weakly positive. Previous studies identified stronger positive association. Differences in the results may be due to a lack of experience on the part of the students and a low number of participants.

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