Dissertations / Theses: 'Tissue Doppler'

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Killich, Markus. "Tissue Doppler Imaging." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-67089.

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Storaa, Camilla. "Reproducibility and interpretation in tissue Doppler echocardiography." Doctoral thesis, KTH, Physics, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3818.

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As cardiovascular disease is the single most common cause ofdeath in the western world, and since there is a closeconnection between cardiovascular disease and left ventricular(LV) function, good methods for the assessment of LV functionis highly needed. A widely used tool for the diagnosis of LVdisease is echocardiography, a technique which today faces twodi_culties; the low reproducibility and the subjectiveinterpretation. The present dissertation aims to quantifyreproducibility, to study the factors that influencereproducibility and to provide tools for simplifying theinterpretation of tissue velocities measured by Dopplerultrasound.

The reproducibility has been studied by letting twoindependent observers measure tissue Doppler velocities toinvestigate how well their measurements agree. To improvereproducibility an algorithm for the automatic detection ofpre-defined echocardiographic localizations is presented. Oneof the most difficult skills for the sonographer to master,thus leading to reduced reproducibility, is the transducermanipulation. The effect of poor transducer manipulation hasbeen modeled, and we show that even a poorly placed transducermay yield images which are easily mistaken for good, however,when scanning in two orthogonal planes the transducermisplacement is easily detected.

Interpretation of the echocardiograms is influenced byseveral parameters. As the tissue velocities are measured byutilizing the Doppler effect, only the velocity componentdirected towards the transducer can be measured, thus thealignment of the heart within the view of the transduceraffects the tissue velocity measurements. The effect of thishas been investigated, and it is demonstrated that since themyocardium primarily has longitudinal motion and thus thevelocity vectors are mainly longitudinal, imaging in the apicalview will give little error in the velocity measurements.

Filtering of the tissue velocity signals have becomecommercially available with the hope that it will improvereproducibility and simplify interpretation. One set of lowpass filters has been tested, and it is seen that there is arisk of overdoing the filtering and cause an underestimation oftissue velocity parameters. A similar effect to low passfiltering is seen when using too low sample rate when recordingthe tissue velocities.

Finally a new imaging modality, tissue motion imaging, ispresented, where myocardial displacement, velocity, strain andacceleration may be interpreted from one single image, insteadof the situation today where several measurements must beperformed to get an overview of all these parameters.

The thesis concludes that reproducibility can be improved bycurve smoothing and that interpretation can be simplified usingadvanced methods of parametric imaging.

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Lindqvist, Per. "Right heart function in health and disease : a Doppler echocardiography and Doppler tissue imaging study /." Doctoral thesis, Umeå : Department of Public Health and Clinical Medicine, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-392.

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Killich, Markus. "Tissue Doppler imaging Erstellung von Referenzwerten für tissue velocity imaging, strain und strain rate beim Hund /." [S.l.] : [s.n.], 2006. http://edoc.ub.uni-muenchen.de/archive/00006708.

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Khan, Sadia N. "Tissue Doppler Echocardiography in the Assessment of Ischaemic Left Ventricular Dysfunction." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525221.

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Koy, Lajos-Alexandros [Verfasser]. "Gewebedopplerechokardiografie (Tissue Doppler Imaging, TDI) bei herzgesunden Brieftauben / Lajos-Alexandros Koy." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2019. http://d-nb.info/1192752414/34.

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Wagner, Tobias. "Tissue-Doppler-Imaging (TDI): Erstellung von Referenzwerten für Tissue Velocity, Strain und Strain-Rate bei der Katze." Diss., lmu, 2006. http://nbn-resolving.de/urn:nbn:de:bvb:19-58358.

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Wagner, Tobias. "Tissue Doppler imaging (TDI) ; Erstellung von Referenzwerten für tissue velocity, strain und strain rate bei der Katze /." [S.l.] : [s.n.], 2005. http://edoc.ub.uni-muenchen.de/archive/00005835.

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Huang, Feiqiong. "Does patent foramen ovale occlusion affect heart? a tissue Doppler imaging study /." [S.l.] : [s.n.], 2004. http://www.diss.fu-berlin.de/2004/198/index.html.

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Shi, Xuegong. "Doppler ultrasound detection of tissue motion and flow generated by external energy /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8032.

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Rotenberg, Shaun. "Blood Flow, Tissue Thickness, and Molecular Changes during Connective Tissue Graft Early Healing." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1273335634.

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Comas, Rovira Montserrat. "Cardiac dysfunction by tissue doppler in earty-and late-onset fetal growth restriction." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/51517.

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SUMMARY 1) Background Fetal growth restriction (FGR) is present in 5-10% of the pregnancies and is associated to high perinatal and long-term cardiovascular morbidity. Subclinical cardiac dysfunction has previously been described in severe and early FGR cases, but not in milder forms of late-FGR. The main aim of this thesis was to assess cardiac function by new echocardiographic techniques on myocardial imaging as Tissue Doppler Imaging (TDI), in early- and late-onset FGR cases. 2) Methods First, tissue Doppler was applied in a cohort of normally growth fetuses by TDI in order to describe its reproducibility and construct reference ranges for fetal annular peak velocities and myocardial performance index at 24-41 weeks of gestation. Secondly, cardiac function including conventional echocardiographic parameters and TDI was evaluated in a cohort of early-onset growth restricted fetuses with abnormal umbilical artery (UA) Doppler and, finally, in a cohort of late-onset small for gestational age (SGA) fetuses with normal UA Doppler. 3) Results Fetal TDI measurements demonstrated a good reproducibility. GA and estimated fetal weight (EFW) adjusted reference ranges for tissue Doppler indices at 24-41 weeks of gestation were provided. TDI demonstrated the presence of both systolic and diastolic cardiac dysfunction in early-onset FGR fetuses. Late-onset FGR fetuses with normal UA were also associated with cardiac dysfunction detected by TDI. 4) Conclusions Early- and late-onset growth restricted fetuses are associated with cardiac dysfunction. Subclinical cardiac dysfunction could be present from early stages of fetal deterioration and could be detected using TDI.

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Hovda, Sigve. "New Doppler-Based Imaging Methods in Echocardiography with Applications in Blood/Tissue Segmentation." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1500.

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Part 1: The bandwidth of the ultrasound Doppler signal is proposed as a classification function of blood and tissue signal in transthoracial echocardiography of the left ventricle. The new echocardiographic mode, Bandwidth Imaging, utilizes the difference in motion between tissue and blood. Specifically, Bandwidth Imaging is the absolute value of the normalized autocorrelation function with lag one. Bandwidth Imaging is therefore linearly dependent on the the square of the bandwidth estimated from the Doppler spectrum. A 2-tap Finite Impulse Response high-pass filter is used prior to autocorrelation calculation to account for the high level of DC clutter noise in the apical regions. Reasonable pulse strategies are discussed and several images of Bandwidth Imaging are included. An in vivo experiment is presented, where the apparent error rate of Bandwidth Imaging is compared with apparent error rate of Second-Harmonic Imaging on 15 healthy men. The apparent error rate is calculated from signal from all myocardial wall segments defined in \cite{Cer02}. The ground truth of the position of the myocardial wall segments is determined by manual tracing of endocardium in Second-Harmonic Imaging. A hypotheses test of Bandwidth Imaging having lower apparent error rate than

Second-Harmonic Imaging is proved for a p-value of 0.94 in 3 segments of end diastole and 1 segment in end systole on non averaged data. When data is averaged by a structural element of 5 radial, 3 lateral and 4 temporal samples, the numbers of segments are increased to 9 in end diastole and to 6 in end systole. These segments are mostly located in apical and anterior wall regions. Further, a global measure GM is defined as the proportion of misclassified area in the regions close to endocardium in an image. The hypothesis test of Second-Harmonic Imaging having lower GM than Bandwidth Imaging is proved for a p-value of 0.94 in the four-chamber view in end systole in any type of averaging. On the other side, the hypothesis test of Bandwidth Imaging having lower GM than Second-Harmonic Imaging is proved for a p-value of 0.94 in long-axis view in end diastole in any type of averaging. Moreover, if images are averaged by the above structural element the test indicates that Bandwidth Imaging has a lower apparent error rate than Second-Harmonic Imaging in all views and times (end diastole or end systole), except in four-chamber view in end systole. This experiment indicates that Bandwidth Imaging can supply additional information for automatic border detection routines on endocardium.

Part 2: Knowledge Based Imaging is suggested as a method to distinguish blood from tissue signal in transthoracial echocardiography. This method utilizes the maximum likelihood function to classify blood and tissue signal. Knowledge Based Imaging uses the same pulse strategy as Bandwidth Imaging, but is significantly more difficult to implement. Therefore, Knowledge Based Imaging and Bandwidth Imaging are compared with Fundamental Imaging by a computer simulation based on a parametric model of the signal. The rate apparent error rate is calculated in any reasonable tissue to blood signal ratio, tissue to white noise ratio and clutter to white noise ratio. Fundamental Imaging classifies well when tissue to blood signal ratio is high and tissue to white noise ratio is higher than clutter to white noise ratio. Knowledge Based Imaging classifies also well in this environment. In addition, Knowledge Based Imaging classifies well whenever blood to white noise ratio is above 30 dB. This is the case, even when clutter to white noise ratio is higher than tissue to white noise ratio and tissue to blood signal ratio is zero. Bandwidth Imaging performs similar to Knowledge Based Imaging, but blood to white noise ratio has to be 20 dB higher for a reasonable classification. Also the highpass filter coefficient prior to Bandwidth Imaging calculation is discussed by the simulations. Some images of different parameter settings of Knowledge Based Imaging are visually compared with Second-Harmonic Imaging, Fundamental Imaging and Bandwidth Imaging. Changing parameters of Knowledge Based Imaging can make the image look similar to both Bandwidth Imaging and Fundamental Imaging.

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Criton, Aline Laure. "An investigation of real time ultrasound Doppler techniques for tissue motion and deformation analysis." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/29080.

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The objective of this dissertation research is to develop new techniques based on Doppler ultrasound to investigate and visualize changes in tissue dynamic and deformation properties due to atherosclerosis in cardiac and vascular applications. A new technique, to correct for the Doppler angle dependency for tissue motion analysis has been developed. It is based on multiple ultrasound beams, and has been validated in vitro to study tissue dynamic properties. It can measure tissue velocity magnitude with low bias (5%) and standard deviation (10%), and tissue velocity orientation with a bias less then 5 degrees and a standard deviation below 5 degrees. A new Doppler based method, called strain rate, has also been developed and validated in vitro for the quantification of regional vessel or myocardial wall deformation. Strain rate is derived from the velocity information and can assess tissue deformation with an accuracy of 5% and a standard deviation less than 10%. Some examples of cardiac strain rate imaging have been gathered and are described in this thesis. Strain rate, as all Doppler based techniques, suffers from angle dependency limitation. A method to estimate one-component strain rate in any direction in the two-dimensional image not necessarily along the ultrasound beam has been developed. The method allows correcting for the strain rate bias along any user-defined direction. In vitro experiments have shown that qualitative two-component strain rate tensor can be derived. Two-component vector velocity from the moving tissue was acquired and two two-component strain rate images were derived. The images showed agreement with the expected deformation pattern.

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Gupta, Michael. "An Economic Analysis of Implantable Doppler Technology in Head and Neck Reconstruction." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23230.

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The goal of this thesis was to evaluate the cost-effectiveness of implantable Doppler technology (IDT) used to monitor free tissue transfer (FTT) procedures in the treatment of cancer of the upper aerodigestive tract (UADT). First, a systematic review of the literature on the effectiveness of traditional and IDT monitoring techniques was performed. Second, a utility survey using a time trade-off technique was created and administered. The results from this survey were used to establish utility values for health states common in patients undergoing FTT procedures. Third, a cost study using the microcosting data available through the Ottawa Hospital was performed. Finally, a decision analytic model was created and an economic evaluation from the payer perspective was completed. A probabilistic sensitivity analysis (PSA) and a value of information analysis (VOI) were performed. The thesis found that the currently available evidence supports IDT as a cost-effective intervention. Further research should be directed towards determining the effectiveness of both traditional and IDT monitoring.

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Koffas, Haralambos. "An application of Doppler echocardiography and tissue Doppler imaging in the evaluation of cardiac function of normal cats and cats with hypertrophic cardiomyopathy." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/29836.

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The aims of this study were (1) to produce Doppler echocardiographic criteria of normality in cats; (2) to identify differnces in ventricular function using Doppler echocardiography between normal cats and cats with HCM; (3) to investigate diastolic and systolic function in normal cats and cats with HCM, by means of TDI. There was no significant difference in LV FS% between normal and HCM cats although affected cats tended to have higher FS%. Apart from the E deceleration time of mitral inflow, which was prolonged in HCM cats, neither the E/A of mitral inflow nor the IVRT were different between the two groups. The LV flow propagation velocity was significantly lower in the affected group compared to that in normal. Asymptomatic affected cats had a higher S wave and S/D ratio and a lower D wave of pulmonary venous flow (PVF) than normal cats. The time from the Q wave of the ECG to peak systolic velocities of PVF was significantly prolonged in the HCM than in the normal group. HCM cats showed significantly higher aortic and pulmonic velocities than normal cats. The TDI technique revealed evidence of both diastolic and systolic dysfunction in HCM cats. On pulsed TDI data, diastolic dysfunction was expressed with decreased early diastolic velocities, lower early diastolic acceleration and deceleration, prolonged IVRt and decreased E’/A’, mainly along the longitudinal axis of the heart. This study, for the first time, offers evidence for systolic dysfunction in feline HCM. The data presented here provides reference data for future studies in the investigation and better classification of feline cardiac diseases. The successful application of TDI in cats, despite the very small size of their heart and the inherent high heart rate often encountered in this species, provides evidence for the successful application of the technique in human neonatal hearts and experimental small animal models of human diseases.

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Shieh, Bernard D. "Quantitative simulation of backscatter from tissue and blood flow for ultrasonic transducers." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53843.

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Ultrasound imaging is a ubiquitous part of the modern medical diagnostics toolbox. It has widespread applications to many areas of medicine, including angiology, cardiology, nephrology, urology, and obstetrics. It is often preferred over other imaging modalities, such as x-ray computed tomography (CAT) and magnetic resonance imaging (MRI) because it is non-invasive, non-ionizing, inexpensive, and has excellent penetration depth in the body. The design, optimization, and manufacturing of ultrasound transducers used in ultrasound imaging is a challenging engineering problem. Faced with a variety of different imaging environments, ultrasound transducers must often be optimized for performance in very specific applications. This is especially true for catheter-based solutions, such as intracardiac and intravascular ultrasound, where imaging performance is strongly dependent on the strength of backscatter from tissue due to significant limitations in device size, electronics, and signal-to-noise ratio. Currently, there is a need for the accurate and fast simulation of the imaging process used in ultrasound imaging, including the ability to capture the effects of backscatter from a variety of different tissues. This thesis discusses the development of simulation tools for the quantitative simulation of tissue backscatter and blood motion from acoustic fields coupled to spatial array transducers, based on an application of the Rayleigh speckle model to the linear systems model for acoustic diffraction from spatial array transducers. These simulation tools have potential applications in the field of medical ultrasonics, with particular attention to the areas of transducer design and optimization, beamforming and array processing, and image reconstruction. We demonstrate how the simulation tools developed here can be used to characterize array imaging performance and to investigate reconstruction performance of common flow algorithms for Doppler ultrasound imaging.

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Bennett, Michael J. "Signal processing techniques for ultrasonic tissue Doppler and real-time B-mode imaging in cardiology." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/10779.

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Coronary heart disease is the most common cause of death in the UK affecting more than one in five men and one in six women. The cause is generally a constriction of the coronary arteries which supply the heart muscle, or myocardium with blood. In around 95% of cases, the constriction is caused by the process of arteriosclerosis which results in the development of a plaque on the vessel wall. Even though these plaques tend to develop quite slowly, they are sometimes liable to sudden rupture, which causes clotting of the blood in the vessel and hence a sudden reduction in the supply of blood to the myocardium. This thesis is concerned with the signal processing techniques which are used in the form of Doppler Tissue Imaging (DTI) and real-time B-Mode imaging to study the motion of cardiac structures. Although these techniques are well suited to this task, improvements in B-mode contrast resolution and DTI velocity resolution are required if image quality and quantitative measurements are to reach a more acceptable level. Results are presented which demonstrate that the accuracy of the velocity estimations made using DTI can be improved with the use of model based signal processing techniques. The use of the fractional Fourier transform is explored in the context of coded excitation, which is a technique to allow improvements in imaging depth and axial resolution and results are shown which show that this technique is able to offer improvements similar to matched filtering. The combined techniques of empirical mode decomposition and the Hilbert spectrum are used to demonstrate a new interpretation of the physical process underlying non-linear acoustic wave propagation and the existing technique of tissue harmonic imaging.

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McGuinness, Abdollahi Zahra. "Intra-operative optical monitoring of bowel tissue viability based on photoplethysmography and laser Doppler flowmetry." Thesis, City University London, 2015. http://openaccess.city.ac.uk/13684/.

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Determination of bowel viability in patients undergoing bowel resection is essential in gastrointestinal surgery. One of the most common operations in gastrointestinal surgery is bowel resection for patients who have different kinds of bowel cancer or any other occlusion in which anastomosis has to be carried out following the removal of an unhealthy segment of the bowel. Monitoring blood flow in abdominal surgery especially intraoperatively would be a valuable tool for prevention of a postoperative anastomosis complication (e.g. anastomotic leak, which is the main complication after colorectal resection). The development of a continuous method for monitoring perfusion of bowel tissue would assist in early detection of inadequate blood supply which then help to reduce the occurrence of an anastomosis complication. Although various monitoring techniques have been proposed to assess intestinal viability intraoperatively, none of these techniques have proved to be reliable enough to replace visual observation. Therefore, to date there is no widely accepted and readily available intraoperative technique to reliably assess the viability of bowel tissue. The aim of this study was to combine the established techniques, laser Doppler flowmetry (LDF) and Photoplethysmography (PPG), into one probe intended for assessment of perfusion in abdominal tissue during bowel resection intraoperatively. In PPG, changes in transmission of light through tissue due to pulsation of small arteries can be monitored whereas in LDF microcirculatory blood cell velocity and flux can be studied. Such a probe could alert the surgeon immediately of any compromise in blood flow so further investigation and, if necessary, therapeutic steps can be applied immediately to prevent severe consequences. Therefore, custom reflectance PPG along with LDF sensor was designed and built in the form of a probe to investigate the changes in blood volume, blood flow and arterial oxygen saturation in patients undergoing bowel resection. The instrumentation was designed successfully and the data was saved for the further analysis. Twenty-four patients undergoing bowel resection were recruited for monitoring of perfusion and blood flow intraoperatively; twenty had undergone laparoscopy and the remainder had a laparotomy operation. Eight different measurements were performed during each trial. The results revealed that the probe could be an indicator of evaluating perfusion and blood flow changes at different stages of the surgery. The results also suggest that laser Doppler is more sensitive to artefact compared to PPG. Differences in amplitude of PPG between different measurements reveal that the sensor does detect changes in blood volume and flow confirming that it has the ability to verify that pulsatile flow is being preferentially preserved at the last step of the resection procedure (at the edges of the anastomosis sites after anastomosis has been constructed).

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Yamato, Ronaldo Jun. "Avaliação ecocardiográfica com \"Doppler\" tecidual, \"Strain Rate\" e \"Strain\" de cães da raça Golden Retriever com distrofia muscular (GRMD)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-15012009-110605/.

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A ecocardiografia com Doppler tecidual (EDT) e suas derivadas, o Strain Rate (StR) e o Strain (St), têm por finalidade mensurar a velocidade e a deformação miocárdicas, avaliando assim as funções sistólica e diastólica do miocárdio. Devido à grande semelhança entre a distrofia muscular de Duchenne (DMD), que acomete o homem e se caracteriza por contínua degeneração, necrose e fibrose de tecidos musculares esquelético e cardíaco e apresenta caráter recessivo ligada ao cromossomo X, e a distrofia muscular canina (DMC), considerada geneticamente análoga à DMD, alguns modelos experimentais com cães da raça Golden Retriever têm sido desenvolvidos com a finalidade de auxiliar os estudos relacionados com as referidas enfermidades. No presente estudo, 24 cães da raça Golden Retriever, divididos em três grupos denominados controle, portadores e afetados foram avaliados por meio da ecocardiografia convencional bem como por Doppler tecidual, Strain Rate e Strain com o objetivo de avaliar os índices das funções sistólica e diastólica de cães com distrofia muscular, a fim de aprimorar o diagnóstico e, conseqüentemente, o tratamento dos casos de DMD, assim como os de cães com DMC. Observaram-se diferenças entre alguns parâmetros das funções sistólica e diastólica, principalmente entre o grupo controle e o grupo dos animais afetados, sendo então possível afirmar que cães da raça Golden Retriever, afetados pela DMC e sem manifestações clínicas de insuficiência cardíaca congestiva (ICC), apresentam alterações dos índices tanto da função sistólica como da função diastólica, passíveis de serem detectadas pela EDT, St e StR.
Tissue Doppler imaging (TDI), strain rate, and strain allow for recording myocardial velocity and deformity, for assessment of systolic and diastolic function. There is great similarity between Duchennes muscular dystrophy (DMD) that affects humans, characterized by continuous degeneration, necrosis and fibrosis of skeletal and cardiac muscle and is recessive, linked to X-chromosome, and canine muscular dystrophy (CMD), which is considered genetically analogous to the DMD. Some experimental models have been developed in order to study these diseases. In this study, 24 Golden retriever dogs, allocated to 3 different groups (control, bearer and affected) were evaluated by conventional echo and TDI, strain rate (StR) and strain (St) aiming to evaluate systolic and diastolic function indices of dystrophic dogs in order to improve diagnosis and treatment of DMD cases, as well as CMD. Differences were observed in some variables of systolic and diastolic function specially between control and affected groups. It was possible to confirm that Golden Retriever dogs, affected by CMD and without clinical signs of congestive heart failure, present changes in systolic and diastolic indices, detected by TDI, StR and St.

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Lind, Britta. "Evaluation of isovolumic myocardial motions in human subjects using tissue velocity echocardiography /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-651-4/.

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Häggblad, Erik. "In vivo diffuse reflectance spectroscopy of human tissue : from point measurements to imaging /." Linköping : Department of Biomedical Engineering, Linköpings universitet, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15191.

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Braun, Miriam Corinna [Verfasser], and Walter [Akademischer Betreuer] Klockenbusch. "Pränatale Diagnostik bei intrauteriner Wachstumsrestriktion mittels Tissue-Doppler-Imaging-Echokardiographie / Miriam Corinna Braun ; Betreuer: Walter Klockenbusch." Münster : Universitäts- und Landesbibliothek Münster, 2014. http://d-nb.info/1138283126/34.

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Campbell, Brian Thomas. "An evaluation of pulse-wave tissue Doppler echocardiography as a diagnostic tool in cardiac disease states." Thesis, University of Ulster, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412128.

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Steyn, Jan. "The assessment of echocardiographic and tissue Doppler profiles of asymptomatic follow-up patients in cardiology practice." Thesis, Bloemfontein : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/128.

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Thesis (M. Tech.) -- Central University of Technology, Free State, 2010
This main aim of this study was to assess patients in a general cardiology practice in order to determine the systolic and diastolic profiles of these patients. The aim was also to determine what effect life style and risk factors may have on the echocardiographic variables measured during such an examination. The specific aim of this study was the importance of not only examining the systolic function but the necessity to also examine the diastolic profile of patients. Life-style plays an important role, with the main culprit being obesity. Obesity was the single most important factor that affected the diastolic profile of patients seen in this study. With obesity a combination of other risk factors related to obesity was observed. Most abnormalities found due to these risk factors were associated with diastolic changes in the left ventricle. Echocardiography is routinely used in daily practice, but the diagnostic value of this tool can be enhanced if proper analyses of the systolic as well as the diastolic profiles are determined. Many cardiologists only measure the systolic function of the heart as an indication of the well- being of the left ventricle, although in this study it was proven that systolic function did not alter with ageing or with changes in the risk profile. Hundred-and-twelve patients, divided into three age groups, were evaluated in this study. Both systolic and diastolic variables were measured and analysed for abnormalities. None of these patients had systolic function abnormalities, although they had detectable anatomic changes due to ageing, obesity and hypertension. Several abnormalities were found on the diastolic profile of these patients. Muscle thickness increased due to obesity and hypertension and even with ageing, but with no significant abnormalities in the systolic function of the heart. There was a slight increase in the circumferential shortening of the left ventricle and that both the septal and longitudinal functions decreased with ageing. It is noteworthy that even where the systolic function remained normal in ageing subjects, their diastolic profiles changed significantly. Assessment of left ventricular function required a meticulous and systematic approach. In this study forty- one percent of patients visiting this general practice had abnormalities of their diastolic function although their systolic function was normal. It was found that with ageing, especially in the older age group, important abnormalities occur in their diastolic profile. The most common changes were that the E- peak velocity decreased and that the Apeak velocity of the trans-mitral flow increased. It seemed that passive filling decreased with ageing but that active filling increased simultaneously, causing the cardiac output to remain constant in older subjects. This is important to know because diseases affecting the atrium may have a profound effect on the cardiac output of older patients, even if they have normal systolic function, (due to the decreased passive filling they need their active filling or atrial contraction to support a normal cardiac output). An important marker will be to look at the ratio of the E/A- velocities in older patients to determine the ratio of active against passive filling. Other than that, a relatively new tool in echocardiography called tissue Doppler was used to determine what happened to the muscle with ageing. Here it was demonstrated that the different layers of the left ventricle acted differently with ageing. Results showed that the longitudinal fibres weakened with ageing although the circumferential fibres remained unchanged or even strengthened with ageing. It was apparent in this study that the traditional use of only systolic function may not be adequate when evaluating relative asymptomatic patients presenting at a general cardiology practice. It is important to also evaluate the diastolic profiles of these patients in order to scientifically quantify their heart health, even in asymptomatic patients. It is important to routinely evaluate the diastolic profile of patients so that early detection of these diastolic variables can be detected and timely consideration for its treatment can be given by their cardiologist. It is also important to take note of the significance of the obesity problem and the effect it has on the heart’s health. In conclusion, this study emphasizes the importance of the echocardiographic evaluation of diastolic cardiac function in addition to routine systolic evaluation in asymptomatic patients. This will enable the clinician to detect abnormalities early and tailor therapy accordingly. Lifestyle related risk factors, especially obesity, also have significant effects on diastolic cardiac function.

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Borges, Maria Candida Calzada. "Redução da função sistolica e diastolica do ventriculo esquerdo, estimada pela velocidade do anel mitral, em pacientes hipertensos com e sem hipertrofia ventricular." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310233.

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Orientador: Kleber Gomes Franchini
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Estudos epidemiológicos têm estabelecido uma relação contínua entre a massa do ventrículo esquerdo (VE) e o risco cardiovascular na população geral e na população hipertensa. O pior prognóstico de pacientes hipertensos com aumento na massa do VE tem sido, em parte, atribuído à disfunção do miocárdio, mas permanece desconhecido se os pacientes hipertensos sem hipertrofia do VE (HVE) definida pelos critérios habituais apresentam alterações na função do miocárdio. Os índices ecocardiográficos derivados das dimensões do VE e das velocidades do fluxo mitral aferidas através do Doppler têm provado ser geralmente não específicos e insensíveis para a detecção de alterações discretas da dinâmica ventricular. O Doppler Tecidual (DT) tem demonstrado ser um método eficiente e rápido para avaliar a função do miocárdio. Nos pacientes hipertensos com hipertrofia do VE tem sido descrita redução das velocidades sistólica e diastólica inicial. Entretanto não tem sido relatada investigação da função sistólica do miocárdio do VE através do DT em pacientes hipertensos sem ou com discreta elevação da massa do VE. O presente estudo avalia se, através da velocidade sistólica e diastólica aferidas pelo DT, é possível identificar alterações na contração e relaxamento do miocárdio de indivíduos hipertensos com ou sem hipertrofia ventricular definida pelos valores de corte habituais e com fração de ejeção preservada. Para tanto indivíduos normotensos e hipertensos com ou sem hipertrofia do ventrículo esquerdo (índice de massa do VE [IMVE] > 51g/m2.7) foram avaliados através da ecocardiografia convencional e do DT em 5 segmentos do anel mitral. Os subgrupos incluíram indivíduos normotensos não obesos (n=16; idade 51 ± 9 anos; 11 feminino; pressão arterial sistólica [PAS] 109 ± 11 mmHg; índice de massa corpórea [IMC] 24 ± 2,7 Kg/m2 ; IMVE 32 ± 5.5g/m2.7), hipertensos não obesos sem HVE (n=16; idade 54 ± 12 anos ; 12 femininos; PAS 166 ± 15 mmHg; IMC 25 ± 2,7 g/m2; IMVE 42 ± 5,5 g/m2.7) e hipertensos não obesos com HVE (n=22; idade 56 ± 10 anos; 10 feminino; PAS 181 ± 19 mmHg; IMC 26 ± 2,3 g/m2; IMVE 69 ± 16 g/m2.7). A fração de ejeção foi comparável entre os subgrupos, mas a fração de encurtamento da parede média foi reduzida nos pacientes hipertensos com hipertrofia do VE (¿26%). O tempo de relaxamento isovolumétrico foi aumentado nos pacientes hipertensos com hipertrofia do VE, enquanto a velocidade A do fluxo mitral encontrou-se aumentada em indivíduos hipertensos com e sem hipertrofia do VE. A velocidade sistólica (SM) e diastólica inicial (EM) aferida através do DT ao nível do anel mitral encontraram-se significativamente reduzidas nos indivíduos hipertensos com e sem HVE quando comparadas com as dos indivíduos normotensos. Evidenciou-se correlação positiva entre SM e EM (r=0,68; p<0,0001) e correlação negativa entre essas duas variáveis e o IMVE (SM, r= -0,41; p=0,002; EM, r= -0,56; p<0,0001). Portanto a redução na velocidade sistólica e diastólica ao nível do anel mitral acompanha o aumento da massa do VE em indivíduos hipertensos, iniciando-se em níveis de IMVE que se encontram abaixo dos valores definidos clinicamente como normais
Abstract: Epidemiological studies have established a continuous relationship between the left ventricular (LV) mass and cardiovascular risk in the general and hypertensive population. The poorer prognosis of hypertensive subjects with major increases in LV mass has been, in part, attributed to myocardial dysfunction, but it remains unknown whether hypertensive subjects without clinically defined LV hypertrophy have subtle abnormalities of myocardial function. Echocardiographic indices derived from LV chamber dimensions and Doppler measurements of flow velocities have been proved to be generally nonspecific and insensitive for the detection of minor abnormalities of cardiac relaxation and contraction. Tissue Doppler imaging (TDI) has been advocated as a reliable, rapid, and efficient method to assess myocardial function. In hypertensive patients with LV hypertrophy, TDI mitral annulus systolic and diastolic velocities have been shown to be reduced. However, a comprehensive TDI approach has not been reported in hypertensive subjects without or with minor increases in LV mass. The present study examines whether, by using TDI early systolic and diastolic velocities, one might identify changes in LV myocardial contraction and relaxation in subsets of hypertensive with and without clear-cut, clinically defined LV hypertrophy and normal LV ejection fraction. Normotensive and hypertensive subjects with and without left ventricular (LV) hypertrophy (LV mass index [LVMI] =51 g/m2.7) were examined by conventional echocardiography and tissue Doppler imaging of mitral annulus motion. The subgroups included non obese normotensive subjects (n=16; age 51±9 years; 11 female; systolic blood pressure [SBP] 109±11 mm Hg, body mass index [BMI] 24±2.7 kg/m2; LVMI 32±5.5 g/m2.7), non obese hypertensive subjects without LV hypertrophy (n=16; age 54±12 years; 12 female; SBP 166±15 mm Hg; BMI 25±2.7 kg/m2; LVMI 42_5.5 g/m2.7), and hypertensive subjects with LV hypertrophy (n=22; age 56±10 years; 10 female; SBP 181±19 mm Hg; BMI 26±2.3 kg/m2; LVMI 69±16 g/m2.7). Ejection fraction was comparable among the subgroups, but midwall fractional shortening was reduced in hypertensive subjects with LV hypertrophy (¿26%). Isovolumic relaxation time was increased in subjects with LV hypertrophy, whereas mitral wave A velocity was increased in hypertensive subjects with and without LV hypertrophy. Tissue Doppler imaging mitral annulus systolic (SM) and diastolic (EM) velocities were reduced in subjects with and without LV hypertrophy compared with normotensive subjects. There was a positive correlation between SM and EM (r=0.68; P<0.0001) and negative correlations between these 2 variables and LVMI (SM, r= -0.41; P=0.002; EM, r=-0.56; P<0.0001). Thus, reductions in mitral annulus systolic and diastolic velocities parallel increases in LV mass in hypertensive subjects, beginning at LV mass within the clinically defined normal values
Doutorado
Medicina Experimental
Doutor em Fisiopatologia Medica

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Amundsen, Brage Høyem. "Myocardial function quantified by speckle tracking and tissue Doppler echocardiography – Validation and application in exercise testing and training." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for sirkulasjon og bildediagnostikk, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2157.

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Storaa, Camilla. "Investigations of strain calculated from ultrasound Doppler tissue velocities as tool for the assessment of left ventircular function." Licentiate thesis, KTH, Physics, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1404.

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Nair, S. V. "The role of brain natriuretic peptide and tissue doppler echocardiography in the management of transfusion dependent thalassaemia patients." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1355954/.

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Background: Iron induced heart failure is the commonest cause of death in thalssaemia major. The cardiomyopathy is reversible when treated early, but once symptomatic heart failure occurs, the outlook is poor. A recent technique using magnetic resonance myocardial T2* (T2 star) has been validated for the assessment of early myocardial iron deposition. Worldwide however, transthoracic echocardiography is the mainstay of assessment for these patients. Conventional echo parameters are poor at identifying those with cardiac iron loading who are at risk of cardiac failure, only becoming abnormal once significant iron loading has occurred. Newer techniques involving tissue Doppler imaging (TDI) have been promising. Our aim was to explore the role of these techniques and that of brain natriuretic peptide (BNP), a biomarker released in heart failure, in the management of Thalassaemia major patients. Methods/Results: 167 patients with thalassaemia major were screened with cardiac T2* MRI to quantify iron loading. Those with severe cardiac iron, T2* <8ms, (n=15) were treated with both desferrioxamine and deferiprone chelation. Those with mild to moderate cardiac iron, T2* 8- 20ms, (n=65) were randomised to desferrioxamine plus either deferiprone or placebo. Both groups were treated for 12 months. At baseline, 6 and 12 months all those in the combination therapy trial and in the severe group were assessed with T2*, full transthoracic echocardiography including TDI and BNP levels. BNP only became abnormal in those with obvious clinical heart failure. TDI systolic velocities in the septum and RV were significantly lower in those with severe cardiac iron and improved over 12 months, correlating with an improvement in T2*. Conclusion: In thalassaemia patients, BNP is unhelpful in assessing cardiac iron status. Systolic tissue velocities can give an indication as to an individuals cardiac iron status and could help to monitor their progress during chelation therapy.

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Lamboul, Benjamin. "Analysis of the potential for coded excitation to improve the detection of tissue and blood motion in medical ultrasound." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4801.

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Doppler ultrasound imaging modalities arguably represent one of the most complex task performed (usually in real time) by ultrasound scanners. At the heart of these techniques lies the ability to detect and estimate soft tissues or blood motion within the human body. As they have become an invaluable tool in a wide range of clinical applications, these techniques have fostered an intensive effort of research in the field of signal processing for more than thirty years, with a push towards more accurate velocity or displacement estimation. Coded excitation has recently received a growing interest in the medical ultrasound community. The use of these techniques, originally developed in the radar field, makes it possible to increase the depth of penetration in B-mode imaging, while complying with safety standards. These standards impose strict limits on the peak acoustic intensity which can be transmitted into the body. Similar solutions were proposed in the early developments of Doppler flow-meters to improve the resolution / sensitivity trade-off from which typical pulsed Doppler systems suffer. This work discusses the potential improvements in resolution, sensitivity and accuracy achievable in the context of modern Doppler ultrasound imaging modalities (taken in its broadest sense, that is, all the techniques involving the estimation of displacements, or velocities). A theoretical framework is provided for discussing this potential improvements, along with simulations for a more quantitative assessment. Colour Flow Imaging (CFI) modalities are taken as the main reference technique for discussion, due to their historical importance, and their relevance in many clinical applications. The potential achievable improvement in accuracy is studied in the context of modern velocity estimation strategies, which can be broadly classified into narrowband estimators (such as the “Kasai” estimator still widely used in CFI) and time shift based wideband strategies (normalised crosscorrelation estimator used, for instance, in applications like strain or strain rate estimation, elastography, etc.). Finally, simulations and theoretical results are compared to experimental data obtained with a simple custom-designed experimental set-up, using a single-element transducer.

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Pellegrino, Arine. "Ecocardiografia tecidual em gatos da raça Maine Coon geneticamente testados para a cardiomipatia hipertrófica." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-01062012-165319/.

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A cardiomiopatia hipertrófica (CMH) é a principal cardiopatia dos felinos e é caracterizada por hipertrofia miocárdica concêntrica, sem dilatação ventricular. Disfunções miocárdicas ocorrem em gatos com CMH, mas pouco se conhece a respeito destas alterações nos estágios iniciais da afecção. Em gatos da raça Maine Coon, a mutação no gene MyBPC-A31P está relacionada com a CMH de origem familial, porém, a correlação exata entre o genótipo e o fenótipo ainda é inconclusiva. A ecocardiografia tecidual é uma modalidade não invasiva que permite avaliação da função miocárdica e é mais sensível que a ecocardiografia convencional. Para avaliar a função sistólica e diastólica, antes ou após a ocorrência de hipertrofia ventricular, gatos da raça Maine Coon (n=57), geneticamente testados para a mutação, foram avaliados por meio de ecocardiografia convencional e tecidual (nas modalidades Doppler tecidual pulsado, Doppler tecidual colorido e strain). Posteriormente, foram fenotipicamente classificados em: normais (n=45), suspeitos (n=7) e acometidos pela CMH (n=5); e genotipicamente classificados em: negativos (n=28), heterozigotos (n=26) e homozigotos para a mutação (n=3). Valores de velocidades miocárdicas (Doppler tecidual pulsado e colorido) e valores de strain, medidos na região basal e média do septo interventricular (SIV), da parede livre do ventrículo esquerdo (PVE), da parede anterior do ventrículo esquerdo (PAVE), da parede posterior do ventrículo esquerdo (PPVE) e do segmento radial da PVE, foram comparados nos diferentes grupos. Observou-se que as velocidades longitudinais Em (Doppler tecidual pulsado) na região média da PVE foram menores nos gatos com CMH quando comparados com suspeitos e normais. Os valores de Em/Am (Doppler tecidual colorido), na região basal do SIV, foram inferiores nos gatos com CMH quando comparados com suspeitos e normais. A relação E/Em (Doppler tecidual colorido), na região basal do SIV, foi maior nos gatos com CMH em relação aos suspeitos e normais. E os valores de Sm (Doppler tecidual colorido), em região basal da PVE, foram menores nos gatos heterozigotos em relação aos negativos, ambos sem hipertrofia ventricular. Observou-se correlação positiva entre a ocorrência de fusão das ondas Em e Am e a frequência cardíaca; e correlação positiva entre valores de Sm e Em e a frequência cardíaca (Doppler tecidual pulsado e colorido). Enquanto à ecocardiografia convencional observou-se um estado de contratilidade aparentemente normal, os valores de strain (em região média do SIV) nos gatos com CMH foram inferiores aos dos gatos normais. Valores de strain (em região basal da PAVE) também foram menores nos gatos heterozigotos em relação aos negativos, antes mesmo da hipertrofia ventricular. Observou-se correlação negativa entre valores de strain e espessura miocárdica. A ecocardiografia tecidual é uma nova modalidade ecocardiográfica reprodutível em gatos que, isoladamente, não permite a identificação de gatos com mutação antes do desenvolvimento de hipertrofia. O strain possibilita a detecção de anormalidades sistólicas em gatos da raça Maine Coon, apesar da aparente normalidade à ecocardiografia convencional. Apesar da expectativa em relação ao uso da ecocardiografia tecidual para a identificação precoce de indivíduos portadores da CMH, ainda há necessidade de estudos mais extensos e com maior número de indivíduos.
Hypertrophic cardiomyopathy (HCM) is the most common feline heart disease and is characterized by increased cardiac mass with a hypertrophied nondilated left ventricle. Myocardial dysfunction occurs in cats with HCM but less is known about dysfunctions in initial stages of HCM. A mutation in MYBPC-A31P gene has been identified in a colony of Maine Coon cats with HCM. However, the close correlation between genotype and phenotype still be inconclusive. Myocardial analysis by tissue Doppler imaging (TDI) is a noninvasive echocardiographic method to assess systolic and diastolic function that is more sensitive than conventional echocardiography. To evaluate diastolic and systolic function in cats with mutation, with or without ventricular hypertrophy, Maine Coon cats (n=57) were screened for mutation and examined with both echocardiography and TDI (pulsed tissue Doppler, color tissue Doppler and Strain methods). Then, were phenotypically classified in: normal (n=45), suspects (n=7) and HCM group (n=5); and genotypically classified in: negative (n=28), heterozygous (n=26) and homozygous group (n=3). Myocardial velocities (by pulsed and color tissue Doppler imaging) and peak myocardial strain, measured in the basal and mildventricular segment of the interventricular septal wall (IVS), left ventricular free wall (LVW), left ventricular anterior wall (LVAW), left ventricular posterior wall (LVPW) and radial segment of LVW, was compared among different groups. A decreased longitudinal Em velocities (pulsed tissue Doppler) at the mildventricular segment of LVW was observed in HCM cats compared with suspects and normal cats. A decreased longitudinal Em/Am (color tissue Doppler) at the basal segment of IVS was observed in HCM cats compared with suspects and normal cats. A significant increased longitudinal E/Em (color tissue Doppler) at the basal segment of IVS was observed in HCM cats compared with suspects and normal cats. And a significant decreased longitudinal Sm (color tissue Doppler) at the basal segment of the LVW was observed in heterozygous cats compared with negative cats, both without hypertrophy. There was a positive correlation between summated early and late diastolic velocities (EmAm) and heart rate; and a positive correlation between Sm and Em velocities and heart rate, both in pulsed and in color TDI. Whereas conventional echocardiography demonstrated an apparently normal contractile state, myocardial strain (at mildventricular segment of IVS) in HCM cats was decreased compared with normal group. Myocardial strain (at basal segment of LVAW) also was decreased in heterozygous cats compared with negative group; and was decreased in heterozygous cats compared with negative group, both without ventricular hypertrophy. And there was a negative correlation between strain values and wall thickness. TDI analyses are a new, valuable and reproducible method in cats that alone is not able to identify cats with mutation before myocardial hypertrophy. Strain method allows noninvasive detection of abnormal systolic deformation in Maine Coons cats with HCM mutation despite apparently normal left ventricular systolic function. Despite high expectations regarding the use of TDI for early identification of individuals with HCM, there is still need for larger studies with greater numbers of individuals.

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Zhao, Yunqin. "SPECTRAL CALIBRATION FOR SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY BASED ON B-SCAN DOPPLER SHIFT WITH IN SITU. TISSUE IMAGES." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1562594660964602.

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Segun, Utomi Victor. "The 'athletic heart' : insights from modern imaging tools in Caucasian and West African athletes." Thesis, Liverpool John Moores University, 2015. http://researchonline.ljmu.ac.uk/4557/.

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A seminal study by Morganroth et al (1975) demonstrated a differential pattern of cardiac adaptation with prolonged exercise training; of eccentric pattern of left ventricular hypertrophy (LVH) in endurance trained athletes (ET) and concentric LVH in resistance trained athletes (RT). Specific inconsistencies related to the nature of any adaptation to RT; the value of new imaging technologies; the relative importance of scaling of cardiac data for differences in body size; the impact of training on the right ventricle (RV) and the fit of differential pattern of adaptation in athletes with Black ethnicity have driven the rationale for the studies included in this thesis. Study one employed meta-analysis techniques to critically evaluate the evidence base supporting or refuting that MH exists in elite male Caucasian ET & RT. Modern echocardiographic techniques were used to test whether a dichotomous LV and RV structural as well as global and regional functional adaptation was apparent in elite Caucasian ET & RT in studies 2 & 3. The final study (exploratory) was to characterize the athletic heart phenotype in a homogenous population of elite RT of West African origin (WRT) to provide new insight in relation to cardiac adaptation and ECG characteristics in non-Caucasian athlete groups. Allometric scaling approach was deployed to index LV and RV data for individual body variance in body size. The novel findings of this thesis; larger LV data in ET (LVMg: ET 232 (200 to 260), RT 220 (205 to 234), CT 166 (145 to 186)) but no concentric hypertrophy in RT within the meta-analysis, predominance of normal geometry in male athletes (65% of ET and 95% of RT) and the lack of concentric pattern of hypertrophy in RT in a cross-sectional study; no RV adaptation in RT athletes (RVD1mm: ET 45 ± 5 (39 to 57), RT 40 ± 5 (32 to 51) CT 39 ± 4 (31 to 45)); no LV or RV adaptation in WRT athletes; the importance of appropriate scaling of cardiac parameters; provide a useful re-evaluation of concepts and models in the athletic heart literature. The findings have important implications for cardiovascular screening of athletes.

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Göransson, Lizette, and Filippa Fredlund. "En jämförelse mellan mättekniker för högerkammarbedömning vid ekokardiografi : Överensstämmelse mellan s´ och TAPSE." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-35877.

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Bedömningen av höger kammares systoliska funktion kan med fördel göras med ekokardiografi, bl.a. med tekniker som tvådimensionell ekokardiografi, motion-mode (M-mode) och Tissue Doppler Imaging (TDI). Mätvärden som kan fås ut av dessa tekniker är Tricuspid Annular Plane Systolic Excursion (TAPSE) och s`. TAPSE beskriver annulus tricuspidalis longitudinella rörlighet. s´ beskriver den maximala systoliska hastigheten i annulus tricuspidalis. Syftet med examensarbetet var att undersöka sambandet mellan TAPSE och s´ vid högerkammarfunktionsbestämning. Studien är en retrospektiv tvärsnittsstudie och består av 99 deltagare i åldrarna 18–90 år. Både friska och hjärt-och kärlsjuka deltagare inkluderades, men inte patienter med förmaksflimmer eller individer som var yngre än 18 år. Deltagarna undersöktes med transthorakal ekokardiografi (TTE) vid Länssjukhuset Ryhov i Jönköping, vid undersökningen mättes TAPSE och s´. Det var samma biomedicinska analytiker (BMA) som utförde undersökningarna. McNemars test utfördes och ett Kappa-värde räknades ut. Resultatet visade signifikant skillnad och Kappa-värdet var lågt vilket talar för dåligt samband mellan de båda variablerna. Utfallet i studien visar att fler deltagare klassas med normal högerkammarfunktion mätt med TAPSE, medan samma individer klassas med högerkammardysfunktion mätt med s´. Orsaken till det dåliga sambandet mellan parametrarna är okänt och bör studeras vidare i kommande studier.
The assessment of right ventricular systolic function is done by echocardiography, with techniques as twodimensional echocardiography, motion-mode (M-mode) and Tissue Doppler Imaging (TDI). Measurements obtained from these techniques are Tricuspid Annular Plane Systolic Excursion (TAPSE) and s`. TAPSE describes the longitudinal movement of annulus tricuspidalis. s´ describes annulus tricuspidalis maximal systolic velocity. The purpose of this essay was to explore the relationship between TAPSE and s´. The study consists of 99 participants between the ages of 18 and 90. The population was consisted of individuals with or without cardiovascular disease, but not individuals with atrial fibrillation. Participants were investigated with transthorakal echocardiography (TTE) at Länssjukhuset Ryhov in Jönköping. At the examination both TAPSE and s´ was measured. McNemar's test was performed and a Kappa value was calculated. The result showed a significant difference and the Kappa value was low which indicates a low relationship between the variables. The outcome of the study shows that several participants are classified with normal right ventricular function measured with TAPSE, but the same individuals are classified with right ventricular dysfunction measured by s'. The reason for the poor relationship between the parameters is unknown and should be studied further in future studies.

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Hübbert, Laila. "Between the Probe and the Pump : An experimental study on cardiac performance analysis based on Echocardiography, tissue and laser Doppler." Doctoral thesis, Linköpings universitet, Kardiologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-61518.

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Echocardiography is an ultrasound-based bedside, non-invasive and easily available cardiac diagnostic technique visualising the heart’s morphology and function. Quantification of cardiac wall motion can be measured with the tissue Doppler Imaging (TDI) modality which provides in humans a high diagnostic capacity to differentiate healthy from diseased myocardium with reduced function. Heart failure, as a consequence of, for example, myocardial or ischaemic heart disease, demands both bedside and intraoperative diagnostic procedures for myocardial functional and perfusion assessment. In the late stages of heart failure cardiac left ventricular assist devices (LVAD) may be the treatment of choice. Such new technologies are commonly evaluated in large animals before application in humans is accepted. With the aim of evaluating TDI´s applicability and feasibility in a large animal model 21 calves (aged 3 months and weight around 70 kg), were studied with colour TDI (Paper I). Analysis was performed either during coronary artery occlusion when the laser Doppler perfusion imaging technique (LDMP) was refined (Paper II), or after implantation of the LVAD, Heart Mate II® (Papers III, IV). All animals were haemodynamically monitored (pressures, flows, heart rate) and ECG was continuously recorded. Transthoracic and epicardial echocardiography (TTE) were performed before and after sternotomy and intraoperatively during experimental progressive heart failure. Heart chamber dimensions, native stroke volume, systolic and diastolic regional basal myocardial peak velocities (cm/s; systolic S´, early diastolic E´, and atrial A´, strain (%), strain rate (s-1) and displacement (mm) were determined. Second harmonic imaging (SHI) was applied in order to better visualise air bubbles (Paper IV). In Paper I compiled baseline values were established before and after sternotomy for central haemodynamic and echocardiographic parameters, including the TDI myocardial motion variables velocity, strain rate, strain and displacement. Blood pressure and heart rate changed significantly after sternotomy, but the TDI derived data did not change significantly. In Paper II we report that movement artifacts of the laser Doppler myocardial perfusion measurements can be reduced, both when myocardium is normally perfused and during coronary occlusion, by using the TDI velocity registrations showing wall motion to be minimal. The optimum interval depends on the application but late systole as well as late diastole is preferred. After LVAD implantation in Paper III the flow characteristics and myocardial motion during variations in afterload TDI show that myocardial velocities decrease concomitantly with myocardial depression and are significantly correlated to native stroke volume, heart rate, systemic arterial resistance and cardiac output, but not with left ventricular size, fractional shortening or pump speed. Echocardiography together with TDI thereby offers additional means for monitoring and quantifying residual myocardial function during LVAD treatment. SHI is superior in the early detection of single air-bubbles in the ascending aorta prior to significant air embolism during manipulation of the LVAD pump speed, as shown in Paper IV. A prompt decrease in size of the left atrium during speed adjustment may be a warning that massive air embolism is imminent whereas the commonly used left atrial pressure not provide the same warning.
The title of article II is in the list of publications "Correlation between laser Doppler perfusion monitoring and myocardial tissue Doppler echocardiography in the beating heart" and in the published article the title is "Myocardial tissue motion influence on laser Doppler perfusion monitoring using tissue Doppler imaging".

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Melo, Priscylla Ramos Rosa. "Relação entre concentração plasmática de Nt-proBNP e função diastólica de ventrículo esquerdo avaliada pelo ecocardiograma com Doppler tecidual pulsado em cães obesos." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-20022015-144422/.

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A obesidade é uma doença nutricional crescente em humanos e de alta prevalência nos cães. Este distúrbio nutricional e decorrente, principalmente, de um balanço energético inadequado. O excesso de peso pode exacerbar uma doença preexistente e predispor ao desenvolvimento de outros problemas de saúde, como Diabetes mellitus, aumento dos níveis de colesterol e triglicérides, doenças hepáticas, lesões osteoarticulares, hipertensão, alterações cardíacas e respiratórias. Em medicina humana, a associação entre hiperinsulinemia, hiperlipidemia, hiperleptinemia, hipertensão arterial, hipertrofia ventricular e disfunção cardíaca demonstra que a obesidade e um fator de risco para a doença cardiovascular. O aminoterminal peptídeo natriurético tipo B (Nt- proBNP) é um marcador útil de disfunção ventricular nas doenças cardíacas em humanos, bem como em cães e gatos. No entanto, ainda não está claro como interpretar os níveis de Nt- proBNP em pacientes obesos, visto que os níveis deste peptídeo parecem ter correlação negativa com o índice de massa corpórea. A disfunção diastólica é comumente observada em indivíduos obesos e pode ser detectada precocemente por meio de ecocardiograma Doppler tecidual pulsado. Assim, considerando que os diversos estudos corn Nt- proBNP em humanos obesos são controversos e a inexistência de estudos em animais obesos, o objetivo deste estudo foi avaliar o possível papel dos peptídeos natriuréticos como marcadores pré-clínicos de doença cardíaca na obesidade canina e sua relação com os parâmetros de função diastólica avaliados pelo Doppler tecidual pulsado. Para isto, selecionaram-se 49 cães com escore de condição corporal normal (ECC 5) e 48 obesos (ECC 8 e 9), pareados com relação ao gênero, raça e idade. Os cães obesos apresentaram concentração de Nt- proBNP major que os cães com ECC5/9, e alterações em algumas variáveis ecocardiográficas de função diastólica de VE, avaliadas pelo Doppler tecidual pulsado. Também foi observado aumento na relação Ef/Em associado a alta concentração de Nt-proBNP, sugerindo aumento na pressão de enchimento do ventrículo esquerdo em cães obesos.
Obesity is an increasing nutritional disease in humans, and highly prevalent in dogs. This nutritional disturbance is a consequence of an inadequate energetic balance. Weight excess may exacerbate a pre-existing disease and predisposes to the development of other health problems as diabetes mellitus, increased colesterol and triglyceride levels, hepatic diseases, osteoarticular diseases, hypertension, cardiac and respiratory problems. In human medicine, the association between hyperinsulinemia, hyperlipidemia, hyperleptinemia, arterial hypertension, ventricular hypertrophy and cardiac disfunction demonstrates that obesity is a risk factor for cardiovascular disease. Type B aminoterminal natriuretic peptide (Nt- proBNP) is a useful marker of ventricular dysfunction in heart disease in humans, as well as in dogs and cats. Nonetheless, it is still unclear how to interpret the levels of Nt-proBNP in obese patients, because it has been negatively correlated to body mass index. Diastolic dysfunction is frequently observed in obese patients and may be detected early by pulsed tissue Doppler imaging (TDI). Therefore, considering that controversial results in several studies on Nt-proBNP in obese humans, and the lack of studies in obese animals, the purpose of this study was to evaluate the possible role of Nt-proBNP as preclinical marker of cardiac disease in obese dogs, and the relationship with diastolic function parameters assessed by pulsed TDI. Foully-nine dogs with ideal body score condition (BCS5/9) and 48 obese dogs (BCS 8 and 9/9), were selected, paired for gender, breed/size and age. A higher Nt-proBNP concentration was found in obese dogs in relation to BCS 5/9 dogs, and some changes in echocardiographic variables of diastolic function, assessed by pulsed TDI. There was also increase Ef/Em ratio associated with a higher Nt-proBNP levels, suggesting an increased filling pressure of left ventricle in obese dogs.

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Pereira, Guilherme Gonçalves. "Avaliação ecocardiográfica da função miocárdica ventricular, por meio de Doppler tecidual, em cães da raça Cocker Spaniel Inglês com cardiomiopatia dilatada." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-27092012-161124/.

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A cardiomiopatia dilatada (CMD) é uma das cardiopatias mais frequentes em cães, sendo a redução da contratilidade miocárdica uma de suas principais características. Dentre as raças predispostas, destaca-se o Cocker Spaniel Inglês. O diagnóstico baseia-se nos achados da ecocardiografia convencional. Todavia, as recentes técnicas ecocardiográficas de Doppler tecidual, como a determinação das velocidades miocárdicas, o registro da deformação (Df) e da taxa de deformação (TDf) miocárdicas, podem identificar padrões característicos de disfunção, antes mesmo do surgimento de anormalidades na ecocardiografia convencional. Com o objetivo de investigar os padrões de disfunção miocárdica ventricular, por meio das técnicas retro-mencionadas, foram incluídos 32 cães da raça Cocker Spaniel Inglês, sendo 16 com diagnóstico de cardiomiopatia dilatada e 16 considerados hígidos, para fins de grupo controle. O estudo Doppler tecidual possibilitou a identificação de disfunção miocárdica ventricular sistólica e diastólica, em ambos os ventrículos dos cães com CMD. No ventrículo esquerdo encontrou-se disfunção miocárdica longitudinal e transversal, caracterizada por menor velocidade miocárdica sistólica, retardo eletromecânico, contrações pós-sistólicas longitudinais, redução na Df e TDf sistólicas, além de distúrbio no relaxamento miocárdico. Por sua vez, diminuição da Df miocárdica sistólica longitudinal e retardo no relaxamento miocárdico caracterizaram a disfunção ventricular direita. O presente estudo identificou, de maneira inédita, padrões de disfunção miocárdica, obtidos por meio de Doppler tecidual, em uma população de cães da raça Cocker Spaniel Inglês com CMD.
Dilated cardiomyopathy (DCM) is one of the most common heart diseases in dogs and its main feature is reduced contractility. English Cocker Spaniel is among predisposed breeds. Diagnosis is based on conventional echocardiographic findings. However, recent tissue Doppler echocardiographic techniques, such as myocardial velocities determination and recordings of myocardial strain (St) and strain rate (SR), can identify characteristic patterns of dysfunction, even before the onset of abnormalities in conventional echocardiography. In order to investigate the patterns of ventricular myocardial dysfunction by means of retro-mentioned techniques, 32 English Cocker Spaniels were studied, being 16 diagnosed with DCM and 16 considered healthy for control purpose. Tissue Doppler study allowed identification of systolic and diastolic ventricular myocardial dysfunction in both ventricles of dogs with DCM. Left ventricular findings included longitudinal and transversal myocardial dysfunction, characterized by lower systolic myocardial velocity, electromechanical delay, longitudinal post systolic contractions, reduced systolic St and SR, and myocardial relaxation disturbance. In turn, reduced longitudinal systolic myocardial St and delayed myocardial relaxation characterized right ventricular dysfunction. The present study identified, in an unprecedented way, patterns of dysfunction, obtained by tissue Doppler, in a dog population of English Cocker Spaniels with DCM.

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Liodakis, Emmanouil. "Assessment of left ventriicular mechanical dyssynchrony using real time three dimensional echocardiography and colour coded tissue doppler in heart failure patients." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502125.

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Lindpere, Katharina [Verfasser]. "Echokardiographie bei fetaler Rechtsherzbelastung : Vergleich des Tissue Doppler Imaging mit dem konventionellen M-Mode und dem Color-M-Mode / Katharina Lindpere." Münster : Universitäts- und Landesbibliothek Münster, 2018. http://d-nb.info/1167857275/34.

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Porras, Pérez Antonio Reyes. "Multi-cue image integration for cardiac tissue characterization." Doctoral thesis, Universitat Pompeu Fabra, 2015. http://hdl.handle.net/10803/296796.

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Una caracterización precisa y completa del tejido cardíaco es esencial para el diagnóstico y tratamiento de problemas cardíacos. Para caracterizar la función cardíaca desde diferentes perspectivas, en la práctica clínica, se adquieren grandes cantidades de datos de distinta naturaleza sobre un mismo paciente, proporcionando información útil para la evaluación del corazón. Aunque los distintos datos obtenidos de cada paciente se suelen analizar por separado para evaluar la función cardíaca desde diferentes perspectivas, la combinación efectiva de esta información heterogénea podría ser útil para tener una mejor visión de la anatomía y la función cardíaca. El objetivo principal de esta tesis es el desarrollo de métodos para integrar imágenes e información de distinta naturaleza para una caracterización del tejido cardíaco más completa y precisa.
An accurate and complete cardiac tissue characterization is essential to diagnose and treat heart problems. To characterize cardiac function from different perspectives, large amounts of data of different nature from the same patient are acquired in clinical practice, providing information that is useful for heart assessment. Although the different data obtained from each patient are often analyzed separately to assess cardiac function from different perspectives, the effective combination of this heterogeneous information may be useful for a better insight into heart anatomy and function. The main objective of this thesis is to develop methods to integrate images and information of different nature for a more complete and accurate cardiac tissue characterization.

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Bergstrand, Sara. "Preventing pressure ulcers by assessment of the microcirculation in tissue exposed to pressure." Doctoral thesis, Linköpings universitet, Avdelningen för omvårdnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-109960.

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The overall aim of this thesis was to combine optical methods into a system with the ability to simultaneously measure blood flow changes at different tissue depths. The goal of such a system was to reveal vascular mechanisms relevant to pressure ulcer etiology under clinically relevant conditions and in relation to the evaluation of pressure-redistribution support surfaces. This thesis consists of four quantitative, cross-sectional studies measuring blood flow responses before, during, and after pressure exposure of the sacral tissue. Two optical methods – photoplethysmography and laser Doppler flowmetry – were combined in a newly developed system that has the ability to discriminate blood flows at different tissue depths. Studies I and II explored blood flow responses at different depths in 17 individuals. In Study I the blood flow was related to tissue thickness and tissue compression during pressure exposure of ≥ 220 mmHg. In Study II, the sacral tissue was loaded with 37.5 mmHg and 50.0 mmHg, and the variation in blood flow was measured. Studies III and IV included 42 healthy individuals < 65 years, 38 healthy individuals ≥ 65 years, and 35 patients ≥ 65 years. Study III included between-subject comparisons of blood flow and pressure between individuals in the three study groups lying in supine positions on a standard hospital mattress. Study IV added within-subject comparisons while the individual was lying on four different types of mattress. The studies explored the vascular phenomena pressure-induced vasodilation (PIV) and reactive hyperemia (RH). The most common blood flow response to tissue exposure in this thesis was PIV, although a decrease in blood flow (a lack of PIV) was observed in some individuals. The patients tended to have higher interface pressure during pressure exposure than the healthy groups but no differences in blood flow responses were seen. Our results showed that pressure levels that are normally considered to be harmless could have a significant effect on the microcirculation in different tissue structures. Differences in individual blood flow responses in terms of PIV and RH were seen, and a larger proportion of individuals lacked these responses in the deeper tissue structures compared to more superficial tissue structures. This thesis identified PIV and RH that are important vascular mechanisms for pressure ulcer development and revealed for the first time that PIV and RH are present at different depths under clinically relevant conditions. The thesis also identified a population of individuals not previously identified who lack both PIV and RH and seem to be particularly vulnerable to pressure exposure. Further, this thesis has added a new perspective to the microcirculation in pressure ulcer etiology in terms of blood flow regulation and endothelial function that are anchored in clinically relevant studies. Finally, the evaluation of pressureredistribution support surfaces in terms of mean blood flow during and after tissue exposure was shown to be unfeasible, but the assessment of PIV and RH could provide a new possibility for measuring individual physiological responses that are known to be related to pressure ulcer development.

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Lindberg, Frida. "Ultrasonic Quantification of Skeletal Muscle Dynamics : Feasibility and Limitations." Doctoral thesis, KTH, Medicinsk teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-122233.

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Pain and disorders of the human skeletal muscles are one of the most common reasons for medical consultations in the western countries today and there is a great need to improve both the understanding and treatment of several different muscular conditions. Techniques describing the muscle function in vivo are often limited by either their invasiveness or lack of spatial resolution. Electromyography (EMG) is the most common approach to assess the skeletal muscle function in vivo, providing information on the neurological input. However, the spatial resolution is in general limited and there are difficulties reaching deep musculature without using invasive needles. Moreover, it does not provide any information about muscle structure or mechanical aspects. Quantitative ultrasound techniques have gained interest in the area of skeletal muscles and enables non-invasive and in-vivo insight to the intramuscular activity, through the mechanical response of the activation. However, these techniques are developed and evaluated for cardiovascular applications and there are important considerations to be made when applying these methods in the musculoskeletal field. This thesis is based on the work from four papers with the main focus to investigate and describe some of these considerations in combination with the development of processing and analyzing methods that can be used to describe the physiological characteristics of active muscle tissue. In the first paper the accuracy of the Doppler based technique Tissue Velocity Imaging (TVI) was evaluated in a phantom study for very low tissue velocities and the effect of the pulse repetition frequency was considered. The second paper presents a biomechanical model to describe the TVI strain’s dependency on the muscle fiber pennation angle. In the third and fourth papers the intramuscular activity pattern was assessed through the regional tissue deformation by motion mode (M-mode) strain imaging. The activity patterns were analyzed during force regulation and for the effects of fatigue. The work of this thesis show promising results for the application of these methods on skeletal muscles and indicate high clinical potential where quantitative ultrasound may be a valuable tool to reach a more multifaceted and comprehensive insight in the musculoskeletal function. However, the methodological considerations are highly important for the optimized application and further evaluation and development of analyzing strategies are needed.

QC 20130516

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Itikawa, Paula Hiromi. "Padronização de parâmetros ecocardiográficos, eletrocardiográficos, radiográficos e de pressão arterial sistêmica em cães da raça Dachshund." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-14062017-145546/.

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Os cães da raça Dachshund apresentam acondroplasia/hipocondroplasia, considerada uma condição fisiológica da raça, resultando num corpo longo com os membros curtos, arqueados e musculosos, esterno largo e proeminente, caixa torácica oval e ampla. Essas condições podem dificultar a realização e interpretação de alguns exames. A hipótese desse trabalho é que os cães da raça Dachshund tenham valores ecocardiográficos, eletrocardiográficos, radiográficos e pressóricos diferenciados. Para isso, foram estudados 69 cães adultos e sadios da raça Dachshund, sendo 28 (40,6%) machos e 41 (59,4%) fêmeas; com idade variando de 18 meses a 10 anos de idade; e peso médio de 8,4±2,3 kg. Foram realizados exames ecocardiográfico, eletrocardiográfico, radiográfico, bem como determinação de pressão arterial sistêmica em todos os animais. Para a análise dos resultados, os animais foram categorizados, segundo, gênero, presença ou ausência de castração, faixa etária (A: >1 a ≤ 3 anos, B: >3 a ≤ 6 anos e C: >6 a ≤ 10 anos), peso (< 8 kg e ≥ 8 kg) e circunferência torácica (> 45 cm e ≥ 45 cm). Foram estabelecidos, em cães adultos e sadios da raça Dachshund, os valores de ecocardiografia convencional, eletrocardiografia, radiografia e de pressão arterial sistêmica por meio do método Doppler Os resultados ecocardiográficos principais, com a média e intervalo de confiança de 95% foram: septo interventricular em diástole SIVd (6,5 [6,3-6,7] cm), parede livre de ventrículo esquerdo em diástole PLVEd (6,3 [6,1-6,4] cm), diâmetro interno de ventrículo esquerdo na diástole DIVEd (2,5 [2,5-2,6] cm), diâmetro interno de ventrículo esquerdo na sístole DIVEs (1,2 [1,2-1,3] cm), fração de encurtamento - FE -(51,32 [49,79-52,84]%), fração de ejeção do ventrículo esquerdo Fej (0,84 [0,82-0,85]). Não houve diferença estatística para gênero ou castração. Mas quando os cães foram separados pela faixa etária, houve diferença estatística significativa entre os grupos A e B (p = 0,0073) para SIVd e PLVEd; sendo que os valores para o grupo A foram de: SIVd (6,2 [5,9-6,5] cm) e PLVEd (6,0 [5,7-6,2] cm). Os valores para o grupo B foram: SIVd (6,9 [6,5-7,3] cm) and PLVEd (6,5 [6,3-6,8] cm). Não houve diferença entre o grupo C e os grupos A e B; os valores para o grupo C foram: SIVd (6,4 [5,9-6,8] cm) e PLVEd (6,4 [6,1-6,7] cm). Portanto, cães adultos da raça Dachshund possuem espessura maiores de SIVd e PLVEd quando comparados com valores padronizados para outras raças. Quando os animais foram divididos pelo peso (>8 kg e ≥ 8 Kg), houve diferenças significativas para DVEd (2,44±0,26 cm; 2,64±0,27 cm; p>0,001), como também para circunferência torácica (> 45 cm e ≥ 45 cm), com valores de 2,43±0,25 cm e 2,63±0,27 cm (p>0,001). Também foram estabelecidos valores ecocardiográficos para tamanho do átrio esquerdo, nos eixos látero-lateral e ápico-basilar, respectivamente, iguais a 2,24±0,31 cm e 2,17±0,31 cm; bem como os valores de Doppler tecidual do anel valvar mitral lateral: onda E`=0,11±0,02 m/s, onda A´=0,10±0,02 m/s e razões E´/A´=1,12±0,33 m/s e E/E´=5,91±1,21 m/s. Cães adultos e sadios da raça Dachshund podem apresentar prolapso valvar mitral (40,58%). O valor de pressão arterial sistêmica por meio do método Doppler na cauda de cães Dachshund adultos e sadios foi de 134±20 mmHg diferenciando-se estatisticamente (p > 0,0001) dos valores obtidos no membro torácico (155±28 mmHg).
Dachshund dogs present achondroplasia/hypochondroplasia, considered a breed physiological condition, that results in a long body with short, arched and muscular limbs, large sternum, oval and wide ribcage and developed heart and lungs. All this factors can difficult exams realization and interpretation. The hypothesis is that Dachshund dogs have differentiated echocardiographic, electrocardiographic, radiographic, and systolic blood pressure parameters. Therefore, 69 adult and healthy Dachshund dogs were studied (28 [40.6%] males and 41 [59.4%] females); from 18 months to 10 years-old, weighting 8.4±2.3 kg. Echocardiographic, electrocardiographic, radiographic and systemic arterial pressure evaluations were performed. Animals were categorized according to gender, neutered or not, age group (A: >1 a ≤ 3 years, B: >3 a 6 years e C: >6 a ≤ 10 years), weight (< 8 kg e ≥ 8 kg) e thoracic circumference (< 45 cm e ≥ 45 cm). The values of conventional echocardiography, electrocardiography, radiography and systemic arterial pressure were established in Dachshund dogs using the Doppler method. The main echocardiographic results, with a mean and 95% confidence interval were: interventricular septum in diastole IVSd (6.5 [6.3-6.7] cm), left ventricular free wall in diástole - LVFWd (6.3 [6.1-6.4] cm), left ventricular internal diameter in diastole LVIDd (2.5 [2.5-2.6] cm), left ventricular internal diameter LVIDs (1.2 [1.2-1.3] cm), shortening fraction SF (51.32 [49.79-52.84]%), left ventricular ejection fraction LVEF (0.84 [0.82-0.85]). There was no statistical difference for gender or castration. But when dogs were categorized by age, there was a statistically significant difference between groups A and B (p = 0.0073) for IVSd and LVFWd.; and the values for group A were: IVSd (6.2 [5.9-6.5] cm) and LVFWd (6.0 [5.7-6.2] cm). The values for group B were: IVSd (6.9 [6.5-7.3] cm) and LVFWd (6.5 [6.3-6.8] cm). There was no difference between group C and groups A and B; The values for group C were: IVSd (6.4 [5.9-6.8] cm) and LVFWd (6.4 [6.1-6.7] cm). Therefore, adult dogs of the breed Dachshund have thickness of IVSd and LVFWd when compared with values standardized for other breeds. When animals were divided by weight (< 8 kg and ≥ 8 kg), there were significant differences for LVIDd (2.44 ± 0.26 cm, 2.64 ± 0.27 cm, p (< 0.001), as well as for thoracic circumference (< 45 cm and ≥ 45 cm), with values of 2.43 ± 0.25 cm and 2.63 ± 0.27 cm (p < 0.001). Echocardiographic values were also established for left atrial size, on the latero-lateral and apical-basilar axes at 2.24 ± 0.31 cm and 2.17 ± 0.31 cm, respectively. In addition, the tissue Doppler values of the lateral mitral valve ring: E\' wave = 0.11±0.02 m/s, A\' wave = 0.10±0.02 m/s and E\'/A\' ratios = 1,12±0.33 m/s and E/E \'= 5.91±1.21 m/s. Adult and healthy Dachshund dogs may present with mitral valve prolapse (40.58%). The Doppler method in the tail of healthy Dachshund dogs was 134 ± 20 mmHg, statistically different (p < 0.0001) from values obtained in left forelimb (155 ± 28 mmHg).

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44

Bergstrand, Sara. "Tissue Blood Flow Responses to External Pressure Using LDF and PPG : Testing a System Developed for Pressure Ulcer Research." Licentiate thesis, Linköping : Department of Medical and Health Sciences, Linköping University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-51886.

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45

Ingul, Charlotte Björk. "Quantification of regional myocardial function by strain rate and strain for evaluation of coronary artery disease : Automated versus manual analysis during acute myocardial infarction and dobutamine stress echocardiography." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Medicine, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-777.

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Kvantifisering av hjertets muskelfunksjon med tøyning og tøyningshastighet målt med ultralyd for vurdering av koronar sykdom.

Automatisert metode versus manuell ved akutt hjerteinfarkt og ultralyd stress test.

Vanligvis måles hjertets muskelfunksjon med ultralyd, en mye brukt metode for å diagnostisere hjertesykdommer. Vurderingen av muskelfunksjonen baserer seg i dag på en subjektiv visuell gradering av bevegelsen av hjertemuskelen, og dette krever erfaring. En ny automatisert diagnostisk ultralydsmetode basert på måling av hastigheten i hjertemuskelen gir et kvantitativt mål på muskelens tøyning og sammentrekning. Den nye metoden gir ny og mer detaljert informasjon om hjertets funksjon og om pasientens prognose enn vanlig ultralydsvurdering.

Den nye metoden er mer presis ved oppfølgning etter hjerteinfarkt. Et hjerteinfarkt gir nedsatt bevegelse av muskelen og måles med den nye metoden som nedsatt hastighet som muskelen forkortes med. Små forandringer i den skadde hjertemuskelen, ikke alltid synlige for øyet, kan mer nøyaktig følges over tid med den nye metoden. Utbredelsen av hjerteinfarktet kan også vurderes mer nøyaktig.

Det samme gjelder når angina vurderes under belastning. Når en pasient ikke kan sykle eller gå på tredemølle brukes en medisinsk belastningstest. Ved å belaste hjertet med et medikament som øker hjertemuskelens arbeid samtidig med en ultralydundersøkelse, kan vi oppdage redusert blodforsyningsreserve i hjertet. Stresstesten hjelper til med å vurdere om en trang blodåre bør åpnes etter et hjerteinfarkt, og til å vurdere pasienters risiko for hjertekomplikasjoner før en større operasjon. Den nye metoden gir i tillegg mer informasjon om den langsiktige prognosen sammenlignet med den gamle metoden. Vi har funnet at den nye ultralydsmetoden er mer presis (gir større diagnostisk treffsikkerhet i diagnostikk av koronarsykdom) sammenlignet med den gamle.

Måling av sammentrekningshastigheter i hjertemuskelen ble utviklet og testet på Institutt for sirkulasjon og bildediagnostikk ved NTNU av Andreas Heimdal og Asbjørn Støylen i 1998. Metoden trengte teknisk videreutvikling og testing i et større pasientmateriale. Metoden har ikke fått stor utbredelse på sykehusene pga støyfylte kurver og tidskrevende analyser, men med denne automatiserte metoden blir brukervennligheten større som muliggjør klinisk bruk.

Paper I and II preprinted with kind permission of Elsevier, sciencedirect.com

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Govind, Satish C. "Myocardial Effects of Type 2 Diabetes, Co-morbidities, and Changing Loading Conditions : a Clinical Study by Tissue Velocity Echocardiography." Doctoral thesis, Stockholm : Skolan för teknik och hälsa, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4359.

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47

Kim, Tu-Won [Verfasser]. "Echokardiographische Prädiktoren eines Vorhofflimmerrezidives und atriales Remodeling nach Pulmonalvenenisolation mit einem methodischen Vergleich von Strainmessungen mit Tissue-Doppler-Imaging und Speckle-Tracking-Imaging / Tu-Won Kim." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2011. http://d-nb.info/1025240391/34.

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Sinning, David Leon [Verfasser]. "Tissue Doppler Imaging, Strain Rate und Strain bei Patienten mit Herzinsuffizienzsymptomen trotz normaler Ejektionsfraktion – Diastolische und systolische Funktion gemessen mittels Konduktanzkathetermethode und Echokardiographie / David Leon Sinning." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/102340267X/34.

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Larsson, Matilda. "Quantification and Visualization of Cardiovascular Function using Ultrasound." Doctoral thesis, KTH, Medicinsk teknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11762.

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There is a large need for accurate methods detecting cardiovascular diseases, since they are one of the leading causes of mortality in the world, accounting for 29.3% of all deaths. Due to the complexity of the cardiovascular system, it is very challenging to develop methods for quantification of its function in order to diagnose, prevent and treat cardiovascular diseases. Ultrasound is a technique allowing for inexpensive, noninvasive imaging, but requires an experienced echocardiographer. Nowadays, methods like Tissue Doppler imaging (TDI) and Speckle tracking imaging (STI), measuring motion and deformation in the myocardium and the vessel walls, are getting more common in routine clinical practice, but without a proper visualization of the data provided by these methods, they are time-consuming and difficult to interpret. Thus, the general aim of this thesis was to develop novel ultrasound-based methods for accurate quantification and easily interpretable visualization of cardiovascular function. Five methods based on TDI and STI were developed in the present studies. The first study comprised development of a method for generation of bull’s-eye plots providing a color-coded two-dimensional visualization of myocardial longitudinal velocities. The second study proposed the state diagram of the heart as a new circular visualization tool for cardiac mechanics, including segmental color-coding of cardiac time intervals. The third study included development of a method describing the rotation pattern of the left ventricle by calculating rotation axes at different levels of the left ventricle throughout the cardiac cycle. In the fourth study, deformation data from the artery wall were tested as input to wave intensity analysis providing information of the ventricular – arterial interaction. The fifth study included an in-silico feasibility study to test the assessment of both radial and longitudinal strain in a kinematic model of the carotid artery. The studies showed promising results indicating that the methods have potential for the detection of different cardiovascular diseases and are feasible for use in the clinical setting. However, further development of the methods and both quantitative comparison of user dependency, accuracy and ease of use with other established methods evaluating cardiovascular function, as well as additional testing of the clinical potential in larger study populations, are needed.
QC 20100727

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Sculthorpe, Nicholas. "Left ventricular long axis dynamics in pathological and physiological left ventricular hypertrophy." Thesis, University of South Wales, 2002. https://pure.southwales.ac.uk/en/studentthesis/left-ventricular-long-axis-dynamics-in-pathological-and-physiological-left-ventricular-hypertrophy(eeeb9f18-b0d5-433b-b261-2907df223717).html.

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Sub-endocardial fibres line the inner surface of both ventricles and are responsible for longitudinal oscillations of the mitral annulus, such oscillations may be measured using tissue Doppler echocardiography (IDE). During systole the annulus descends and during early diastole (ETDE) and atrial systole (ATDE) itascends. This thesis examined whether changes in the velocity of the annulus ineach of these phases of oscillation, measured using tissue Dopplerechocardiography (TDE), could determine the nature of increases in left ventricular size (pathological or physiological). Study one examined differences at rest in longitudinal velocities between individuals with hypertrophic cardiomyopathy (HCM), hypertension (HT), weightlifters, runners and controls, (n = 15 all groups) and all groups were aged between 20 - 36 years. The results demonstrated that both pathological groups had systolic and ETDE velocities significantly lower than groups with physiological hypertrophy (weightlifters or runners) or controls p < 0.05. AIDE however was not significantly different between groups. Additionally runners also demonstrated a significantly higher ETDE than either weightlifters or controls (p < 0.05). Binomial logistic regression identified longitudinal systolic velocity < 9 cm s" 1 and ETDE velocity < 11 cm s" 1 as the best combination of variables to predict pathological increases in heart size. Study two examined older subjects in order to determine whether the criteria set out in study one were applicable to senior athletes. The subject groups were the same as in study one however all subjects were aged between 36-55. In this case systolic annular velocity was significantly lower in groups with pathological LVH but ETDE < 9 cm s" 1 was a better differentiator. Binomial logistic regression identified ETDE < 9 cm s" 1 and a mitral E / A ratio < 1 as the best combination of variables to predict pathological LVH. Study three examined the age related changes in long axis function using the pooled data from studies one and two. This demonstrated that in the pathological LVH groups only ETDE / ATDE ratio was significantly correlated with age (r = - 0.5 p < 0.05) suggesting that there appears to be no summation of the effects of pathology and age on mitral annular velocities. The control groups demonstrated a significant age related reduction in all long axis variables (systolic velocity r = - 0.7 p < 0.05; ETDE r = - 0.6 p < 0.01; ATDE r = 0.5 p < 0.05; ETD E / ATDE r = - 0.5 p< 0.01). Weightlifters however did not demonstrate an age related decline in either systolic or diastolic annular velocities. Runners had no age related decline in systolic annular velocities, and whilst they had an age dependent fall in ETDE ( r = - 0.62 p < 0.05) the older runners ETDE were still significantly faster (p < 0.05) than that seen in control subjects. Study four investigated relationship between mitral annular velocity and VOiruK in runners, weightlifters and controls. These results demonstrated peak exercise E TDE strongly correlated to VO^PEAK (r = 0.8 p < 0.01). ConclusionsTaken together these data suggest that longitudinal velocities of the mitral annulus may be useful in determining the nature of increases in heart size, in addition the increased performance of endurance - trained athletes is due in part to functional changes of the long axis.

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