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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Is keeping in or letting out anger good for your heart?

Lai, Josanna Yuk-Lin January 1990 (has links)
Given the presumed importance of cardiovascular reactivity and the role of anger in the development of hypertension and coronary heart disease, this study is the first to jointly examine three related areas (i.e. gender effects, anger direction preference, and opportunity/no opportunity to aggress following an anger Inducing situation). The present study tested the following hypotheses: a) that cardiovascular reactivity would vary as a function of subjects' gender and direction preference; b) that the rate of cardiovascular recovery would vary as a function of anger direction preference and opportunity/no opportunity to aggress; c) that the subjective feelings of anger after harassment would vary as a function of gender, anger direction preference, and opportunity/no opportunity to aggress; and d) that the evaluation of experimenter's competency and performance would vary as a function of anger preference. 56 females and 49 males executed a math task while being harassed for "poor performance". Next, they were randomly assigned to either write a negative evaluation of the frustrator or to copy a neutral paragraph and then to circle some letters in another paragraph. Heart rate and blood pressure were measured intermittently throughout. Subjects' preferred mode of anger expression (i.e. anger-in versus anger-out) had been previously assessed and cross validated by self as well as peer evaluations. Results indicated that gender was a better predictor than anger direction preference for cardiovascular reactivity to harassment. Complex patterns of recovery were detected with Intriguing sex differences. Results on male diastolic recovery were consistent with a matching hypothesis of anger direction preference but only for anger-out males. In addition, subjective anger for males was related to opportunity/no opportunity conditions, whereas females did not show such a relationship. Female anger-ln's showed quicker systolic recovery than anger-out's. Lastly, the evaluation of experimenter's competency and performance did not vary as a function of anger preference. Therapeutic implications of the findings within the context of anger control as well as trends for future research are discussed. / Arts, Faculty of / Psychology, Department of / Graduate
102

Genetic and environmental factors affecting the incidence of coronary artery disease in heterozygous familial hypercholesterolemia

Hill, John Stuart January 1990 (has links)
Familial hypercholesterolemia (FH) is an autosomal dominant disorder in which the primary defect is a mutation in the LDL receptor. Heterozygous FH is among the most common inborn errors of metabolism and remains as the best example of an inherited defect causing premature coronary artery disease (CAD). This thesis describes the physical and biochemical characteristics of heterozygous FH in a large cohort consisting of 208 women and 156 men. The influence of both genetic and environmental factors on the clinical expression of FH were investigated to better understand the phenotypic variation within FH and thus improve the prediction and treatment of CAD in affected individuals. The general incidence of CAD in this population was lower compared to previous reports but the differences between the sexes were expected. It was shown that men had a much higher frequency of CAD (31%) compared to women (13%) despite having lower concentrations of total and LDL cholesterol. In addition, the average age of onset of coronary symptoms was delayed in females, 55 years compared to 48 years for males. A greater risk of developing CAD for men was associated with low levels of HDL cholesterol and a history of smoking. In women, however, CAD was associated with elevated triglyceride levels and the presence of hypertension. In order to efficiently assess the influence of the co-inheritance of the apolipoprotein E polymorphism in this large FH population, a novel apo E phenotyping procedure was developed. Phenotypes were determined directly from plasma which was neuraminidase treated, delipidated and focused in polyacrylamide minigels. The accuracy of this method was confirmed by making a comparison to the established procedure of phenotyping by isoelectric focusing of delipidated VLDL. The low cost, speed and simplicity of the minigel methodology provided ideal conditions to phenotype a large patient population. The frequencies of the ɛ2, ɛ3 and ɛ4 alleles of apolipoprotein E in 125 unrelated FH subjects did not differ significantly from the normal population. In addition, there was no apparent relationship between apo E4 and the concentration of any of the parameters in the plasma lipid profile. However, the presence of the E2 isoform was associated with significantly elevated triglycerides in both sexes. From this study, it is evident that the mutant FH gene exerts its effect within a system of interacting environmental and polygenic factors that are known to modify atherosclerotic risk. It has been established that the dissimilarity in the frequency of CAD between men and women is related to differences between the impact of known risk factors and the incidence of CAD. Therefore, the importance of the influence of these risk factors and the differences between men and women should be emphasized when treating and predicting the development of CAD in patients with FH. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate
103

Angiografia coronária não-invasiva por meio de tomografia computadorizada: determinação da acurácia de sistema isotrópico com 32 colunas de detectores em pacientes com doença arterial coronariana avançada / Noninvasive coronary angiography by computed tomography: assessment of the accuracy of an isotropic system with 32 detector rows in patients with advanced coronary artery disease

Marco Aurelio Santos Cordeiro 11 July 2005 (has links)
A doença arterial coronária (DAC) avançada caracteriza-se pela presença de vasos calcificados e difusamente estenosados, o que reduz a acurácia da angiografia coronária não-invasiva por meio dos atuais aparelhos de tomografia computadorizada (CT) com 16 colunas de detectores (16-MDCTA). O principal objetivo deste estudo foi tentar demonstrar uma acurácia diagnóstica global de pelo menos 90% para a detecção de estenoses coronárias >= 50% em pacientes com DAC avançada e alta probabilidade de possuírem escores de cálcio coronário elevados, mediante a utilização de um sistema de CT com 32 colunas de detectores, todas capazes de adquirir simultaneamente cortes com 0,5 mm de espessura (32x0,5-MDCTA). Angiografias coronárias sincronizadas ao traçado de ECG foram obtidas por meio da 32x0,5-MDCTA (32 cortes de 0,5 mm, voxels isotrópicos de 0,35x0,35x0,35 mm³, rotação do gantry a 400 ms) em 30 pacientes consecutivos (25 do sexo masculino, com idade média igual a 59±13 anos e índice de massa corpórea médio de 26,2±4,9 Kg/m²) e portadores de DAC avançada. As principais artérias nativas, incluindo seus ramos de primeira ordem com diâmetro >= 1,5 mm bem como os enxertos coronários existentes, foram avaliados de forma independente quanto à presença de estenoses >= 50%. Os stents foram excluídos. As angiografias coronarianas convencionais (realizadas em média 18±12 dias antes das respectivas 32x0,5-MDCTAs) foram analisadas de maneira quantitativa (angiografia coronária quantitativa). A mediana do escore de cálcio de Agatston foi igual a 510 (variação entre 3 e 5066). A sensibilidade, a especificidade e os valores preditivos positivo e negativo para a detecção de estenoses >= 50% nas artérias coronárias nativas foram seguintes: 76% (29/38), 94% (190/202), 71% (29/41), e 96% (190/199), respectivamente. A acurácia diagnóstica global foi de 91% (219/240). Do total de vasos analisados, 20% (69/352) foram excluídos devido à existência de um dos seguintes artefatos: movimento, ruído e baixo realce do contraste radiológico isoladamente ou em conjunto (45/69 ou 65%), distorção da imagem secundária à presença de eletrodo de desfibrilador ou marcapasso (18/69 ou26%), e calcificação arterial excessiva (6/69 ou 9%). Conclui-se que a 32x0,5-MDCTA exclui com precisão as estenoses coronarianas >= 50% em pacientes com DAC avançada e escore de cálcio coronário elevado, com acurácia diagnóstica global de 91% / Advanced coronary artery disease (CAD) is characterized by calcified and diffusely stenotic vessels, hampering accuracy of noninvasive coronary angiography with current 16-detector computed tomography (CT) scanners. The main purpose of this study was to try to demonstrate an overall diagnostic accuracy of at least 90% for detection of coronary stenoses >= 50% by half-millimeter 32-detector CT angiography (32x0.5-MDCTA) in patients with advanced CAD and a high likelihood of having elevated coronary calcium scores. ECG-gated coronary 32x0.5-MDCTA (32x0.5 mm cross-sections, 0.35x0.35x0.35 mm³ isotropic voxels, 400 ms gantry rotation) was performed in 30 consecutive patients (25 male, 59±13 years-old, 26.2±4.9 Kg/m²) with advanced CAD. Major coronary arteries, including >=1.5-mm first order branches, and bypass grafts were independently evaluated for >= 50% stenoses. Stents were excluded. Conventional coronary angiography (performed on average 18±12 days before their corresponding 32x0.5-MDCTAs) was analyzed by quantitative coronary angiography. Median Agatston calcium score was 510 (3-5066 range). Sensitivity, specificity, positive and negative predictive values for detection of >= 50% stenoses in the native coronary arteries were: 76% (29/38), 94% (190/202), 71% (29/41), and 96% (190/199), respectively. Overall diagnostic accuracy was 91% (219/240). Twenty percent (69/352) of the vessels were excluded from the analysis due to one of the following artifacts: motion, noise, and low contrast enhancement isolated or in combination (45/69 or 65%), image distortion secondary to an ICD or pacemaker lead (18/69 or 26%), and severe arterial calcification (6/69 or 9%). We concluded that 32x0.5-MDCTA accurately excludes >= 50% coronary stenoses in patients with advanced CAD and high calcium scores, showing an overall diagnostic accuracy of 91%
104

Vivência de perdas: relação entre eventos significativos, luto e depressão, em pacientes internados com doença arterial coronariana / Experience of losses: relation between significatives events, mourning and depression, in hospitalized patients with coronary artery disease

Rachel Jurkiewicz 08 August 2008 (has links)
Do atendimento a cardiopatas internados, criou-se a categoria vivência de perdas, desencadeada por evento(s) significativo(s) que implica no processo do luto. Segundo Freud (1916), o luto é um trabalho psíquico que requer um tempo para elaboração da perda e de transformação da realidade psíquica, desestruturada pela falta do objeto perdido. Entende-se que o luto é o correlato psicodinâmico da reação manifesta de depressão. Com estes fundamentos, esta pesquisa teve por objetivo geral: investigar vivência de perdas, estados de luto e de depressão. Foram avaliados 44 pacientes com os diagnósticos médicos de infarto agudo do miocárdio e angina, de 33 a 65 anos, 50% mulheres e 50% homens. Utilizados três instrumentos: entrevista semi-estruturada, para avaliação do luto; Inventário de Depressão de Beck, para depressão; Escala de Avaliação e Reajustamento Social de Holmes e Rahe, que avalia porcentagem de probabilidade de apresentar problemas de saúde. Os resultados foram relacionados através do programa Statistical Package for Social Sciences, versão 11.0. Apresenta estado de luto 65,9%, sendo significativas as relações entre: luto e depressão (p<0,05); luto e gênero (p=0,000); presente em 90,9% das mulheres; depressão e gênero (p<0,05). Os eventos significativos relatados com maior freqüência foram: morte de familiares, 47% ou de pessoa próxima, 13%. Também é significativa a relação estatística entre luto e quantidade de mortes relatadas por participante como evento significativo (p<0,05). Sugere vivência de perdas como indicativo de risco psicológico para doença arterial coronariana, apontando para a associação entre luto e depressão / Since the attendance of hospitalized cardiac patients was created the category experience of losses caused by significative(s) event(s) that implicated in the mourning process. According to Freud (1916), mourning is a psychic process that requires time for the loss elaboration and changing of the psychic reality, shaped by the lost object missing. Mourning is understood as a psychodynamic correlation of the manifested depression reaction. On this basis, this research aimed: investigate experience of losses, mourning and depression. 44 patients with medical diagnosis of severe heart attack and angina were evaluated, from 33 to 65 years old, 50% women and 50 % men. Three instruments were used: semi-structured interview for mourning evaluation; Beck Depression Inventory, for depression; Holmes and Rahe Social Readjustment Rating Scale, which evaluates the probability of presenting health problems. The results were treated by the software Statistical Package for Social Sciences version 11.0 . 65,9% presented state of mourning and the association between : mourning and depression were significative (p<0,05); mourning and gender (p=0,000), presented in 90,9% of the women; depression and gender (p<0,05). The significative events more frequently reported were: death of a relative 47%, or closer person 13%. It is also significative the statistical relation between mourning and deaths related by the participants as significative event (p<0,05). Experience of losses is suggested as indicative of psychological risk for coronary artery disease, highlighting the association with mourning and depression
105

Progressão da aterosclerose coronária avaliada pela coronariografia, em portadores de doença multiarterial submetidos a tratamento clínico, cirúrgico ou angioplastia / The progression of atherosclerotic coronary disease assessed by coronary arteriography in patients with multivessel coronary disease undergoing medicine, angioplasty, or surgery treatments

Jorge Chiquie Borges 23 August 2007 (has links)
Introdução: Freqüentemente a progressão da doença coronariana aterosclerótica é observada por angiogramas seqüenciais e atribuída ao aumento da incidência de eventos coronarianos.O significado prognóstico desta progressão em pacientes randomizados e submetidos a diferentes formas terapêuticas ainda é pouco conhecido. Este estudo compara a progressão da aterosclerose nas artérias coronárias nativas de pacientes submetidos a tratamento clinico, cirúrgico ou através da angioplastia. Métodos: 611 pacientes portadores de DAC multiarterial estável com função ventricular preservada, foram estudados e submetidos de maneira randomizada, a três formas terapêuticas habituais. Após cinco anos de evolução, 392 pacientes (64%) foram submetidos à cinecoronariografia. A progressão da doença foi definida como surgimento de estenose de, pelo menos, 20% de obstrução em um segmento arterial, admitido previamente como normal. A progressão foi avaliada nas artérias nativas que correspondem a DA, CX, CD dos três grupos terapêuticos. Resultados: 392 pacientes estudados, 136 eram do grupo Cirúrgico, 146 do grupo Angioplastia e 110 do grupo Clínico. Os grupos eram homogêneos em relação às características basais. A análise de progressão entre os grupos terapêuticos mostrou maior progressão da doença na artéria DA do grupo angioplastia. Entre os fatores relacionados à progressão da doença a presença de HAS influenciou significativamente (p= 0,048). Em relação à oclusão total, houve maior incidência no sexo masculino (p= 0,0078) e novo IAM (p= 0,0006). Não se observou relação estatística entre eventos coronarianos e progressão da doença na amostra estudada. Conclusão: Nessa amostra observou-se a progressão da aterosclerose independente da opção terapêutica. Todavia, encontrou-se menor progressão da doença nos pacientes do grupo cirúrgico. Exceto pela presença de hipertensão, nenhum outro fator de risco parece ter influenciado nesta condição. / Introduction: The progression of atherosclerotic in the coronary artery disease (CAD) is observed through consecutive angiograms. The prognosis of this progression randomized patients is not clear. This study compared the progression of native coronary arteries and bypass graft in patients undergoing to surgery (CABG), angioplasty (PCI), or medical strategy (MT). Methods: Six hundred eleven patients with stable multivessel CAD and preserved ventricular function were randomly assigned to the 3 therapeutic options: MT, PCI, or CABG. After a 5-year of follow-up, 392 patients (64%) underwent routine coronary angiogram. Progression was defined as stenosis of at least 20% in an artery segment previously considered normal. Progression was assessed in the native arteries irrigating the three territories, left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA). Uni and multivariate analysis were performed in all therapeutic groups. Results: Of the 392 patients, 136 were to CABG, 146 PCI, and 110 MT. Baseline characteristics of three treatment were homogeneous. Analysis of progression within the three groups showed a more significant progression of atherosclerosis in the LAD territories of the PCI group. Among the factors related to the progression, there was a significant influence by hypertension (p = 0.048). Males presented a higher incidence of occlusion (p= 0.0078) and new Myocardial Infarction. (p= 0.0006). There was no statistical difference between coronary events and the development of progression in the sample studied. Conclusion: In this study, we have observed the occurrence of atherosclerosis progression, regardless the treatment option. However, we?ve found less progression of disease in patients from the surgery group. Except for hypertension, any other risk factor seems to have no influence on the increase of this condition.
106

Nouvel Outil d'Imagerie IVUS de Palpographie Anisotrope et Caractérisation des Propriétés Viscoélasto-Plastiques du ballon d'Angioplastie : Pour un Meilleur Traitement de la Plaque d'Athérome Coronarienne en Clinique / A Novel Anisotropic Elasticity-Palpography IVUS Imaging Tool and Characterization of the Viscoelasto-Plastic Properties of Angioplasty Balloon : Towards a Better Assessment and Treatment of Coronary Artery Diseases

Gomez Lara, Armida 11 June 2019 (has links)
En dépit des grandes avancées dans le domaine de la recherche médicale, les maladies cardiovasculaires (MCV) représentent toujours l’une des causes principales de mortalité dans le monde, et sont globalement responsables d’un tiers des décès dus à des maladies. En raison de la diversité et de la complexité de ces MCV, les recherches dans des domaines variés tels que la biomécanique, médecine, biologie, anatomopathologie, pharmacologie et imagerie se sont accrues. Ces recherches multidisciplinaires se développent dans l’espoir de mieux comprendre ces pathologies afin de mieux les traiter, ainsi que de réduire les coûts hospitaliers liés aux traitements des patients. Mes travaux de thèse rentrent dans ce cadre-là et s’inscrivent dans le champ de la Biomécanique Cardiovasculaire lié aux maladies coronariennes. Ils visent à développer de nouveaux outils d’aide au diagnostic médical pour la cardiologie interventionnelle.Mon rapport doctoral comporte deux parties :Dans la 1ère partie, je m’intéresse à l’imagerie de la plaque coronarienne obtenue à partir de l’exploration endovasculaire par ultrason (IVUS) pratiquée en clinique et plus particulièrement en utilisant le signal radio-fréquence (RF) IVUS. Le risque de rupture d’une plaque d’athérome coronarienne vulnérable (PV) est lié à la composition composite de sa lésion athéromateuse. Les proximités de tissus biologiques très différents engendrent des gradients d’élasticité importants responsables de concentrations de contraintes de fortes amplitudes, pouvant potentiellement rompre la PV. La mécanique des milieux continus va nous aider à identifier les propriétés mécaniques de tous les constituants de la PV à partir des séquences IVUS obtenues sur patients. Plusieurs études développées au sein de notre laboratoire TIMC (telles que la Palpographie isotrope, la Modulographie isotrope) permettent une quantification préliminaire des propriétés mécaniques de tous les constituants de la lésion. Au sein de cette 1ère partie, je décris dans un premier temps ces techniques existantes, puis dans un 2ème temps je détaille et explique mes travaux de recherche développés lors de ma thèse dans ce domaine d’imagerie. J’ai essayé de répondre aux deux questions essentielles suivantes : 1) Peut-on travailler directement avec le signal IVUS b-mode disponible en routine clinique pour visualiser l’élasticité de la lésion athéromateuse? , et 2) Est-il possible d’améliorer la technique existante de palpographie isotrope afin de tenir compte des propriétés anisotropes de la lésion et de la paroi vasculaire? . Afin d’y répondre, j’ai mené des études à la fois théoriques et expérimentales pour tester les performances des nouveaux outils d’imagerie IVUS proposés.Dans la 2ème partie de ma thèse, je me suis intéressée à l’angioplastie par ballonnet et plus précisément aux propriétés viscoélasto-plastiques du ballon. En effet, il est essentiel pour le cardiologue de prendre en compte l’évolution des propriétés mécaniques du ballon lors de son utilisation répétée, et cela afin de permettre un acte chirurgical plus précis lors du gonflement du ballonnet au sein des artères coronariennes pathologiques. Cette dernière étude peut servir de base au développement d’un modèle biomécanique plus complet permettant de prédire l’évolution de la courbe pression-diamètre du ballon lors de son utilisation et plus particulièrement lors de ses gonflements consécutifs en utilisation clinique. / Cardiac catheterization has evolved from being initially received with great skepticism to becoming a standard for the diagnosis and treatment of cardiovascular disease. A myriad of derived techniques like balloon angioplasty, intravascular imaging, as well as valve and stent implantation are now routine procedures for interventional cardiologists. Despite these and other great advances in cardiovascular medicine, cardiovascular disease (CVD) still represents the main cause of mortality, accounting for as much as one out of three deaths worldwide. Due to the complexity of CVD, it has become the field of study of researchers among various disciplines in hopes to reduce the burden of the disease. One of such disciplines is mechanics, that applies its principles and approaches to create innovative tools to diagnose, prevent and treat CVD.The present thesis belongs to the field of cardiovascular biomechanics and aims to develop tools that can be of assistance to physicians in the diagnosis and treatment of coronary artery disease. This dissertation is divided into two parts:Part I: Imaging the atherosclerotic plaque in clinics, is related to the identification and assessment of coronary atherosclerotic plaque with the presentation of a novel palpography algorithm based on continuum mechanics theory.First, it was investigated whether gray-scale IVUS images are enough for obtaining an accurate elasticity map to assess plaque composition and evolution. Indeed, it was concluded that radiofrequency (RF) data provides more detailed data than b-mode IVUS images. Then a novel anisotropic elasticity-palpography algorithm is described. It computes an apparent elasticity of the plaque from radiofrequency signals obtained through IVUS images. The derivation of an anisotropic index (AI) that can be related to the mechanical properties of the arterial wall, along with a first validation using simulated IVUS images based on real patient geometries of atherosclerotic and healthy plaques is presented. Using this new palpography algorithm, a study was that aimed to validate this technique in vitro was performed. Polyvinyl-alcohol (PVA) cryogel vascular phantoms were fabricated, two of them with increased anisotropy. The phantoms were imaged with IVUS and their mechanical properties were obtained using different characterization techniques. Then, the anisotropy indices modeld with the experimental results and the ones computed with the algorithm were compared.Part II: Balloon angioplasty is focused on the treatment of coronary plaque and analyzes the mechanical properties of the balloons used for coronary angioplasty.First, the visco-elasto-plastic mechanical characterization of a specific balloon catheter model, the Maverick2 from Boston Scientific, is presented. Geometrical measurements using different microscopy techniques, balloon inflation tests, tensile tests and high-speed images are used to describe the mechanical behavior of the balloon components. The previous results are used in to define a model that can accurately predict the viscoelasto-plastic behavior of the angioplasty balloon film. These results could be used as the basis for a model to predict the inflation behavior of the angioplasty balloon during consecutive inflations in clinics.
107

Anxiety-Management Training for the Reduction of Type A Coronary-Prone Behavior

Baskin, Steven Marc 08 1900 (has links)
The present study investigated the effects of anxiety management training on the reduction of Type A coronary-prone behavior in a college student population and utilized behavioral measures as well as self-report indices of change. Evaluations pre- and post-treatment included self-report measures of Type A behavior, empirically validated performance measures of the achievement-striving and time-urgency components of coronary-prone behavior, and a learned helplessness manipulation that has been associated with this behavior pattern. Analysis of covariance indicated that the treatment group changed in the desired direction on all self-report indices, and on most of the performance measures and helplessness scores that were used as dependent variables. Discussion centered on the implications of these data to theoretical and practical conceptualizations of coping behavior and coronary disease and cautions were expressed concerning clinical significance, maintenance, and generalization of results.
108

Diagnostic Accuracy of Pressure-Drop Coefficient (CDP) for Functional Assessment of Coronary Artery Disease using Multicenter International ILIAS Registry Data

Manegaonkar, Shreyash 31 May 2023 (has links)
No description available.
109

Compound formula of danshen (salvia miltiorrhiza) and gegen (pueraria lobata) as adjunctive secondary preventive therapy in coronary patients.

January 2004 (has links)
Tam Wing Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 82-100). / Abstracts in English and Chinese. / English abstrac --- p.I / 中文摘要 --- p.VI / Glossary --- p.X / Chapter Chapter 1. --- Background: / Chapter 1.1. --- Coronary heart disease in Hong Kong --- p.1 / Chapter 1.2. --- Coronary heart disease and atherosclerosis --- p.2 / Chapter 1.3. --- Pathogenesis of atherosclerosis --- p.2 / Chapter 1.4. --- Risk factors for atherosclerosis --- p.5 / Chapter 1.5. --- Homocysteine --- p.6 / Chapter 1.6. --- Folate --- p.10 / Chapter 1.7. --- Vitamin B12 --- p.13 / Chapter 1.8. --- Adhesion Molecules --- p.14 / Chapter 1.9. --- Phytoestrogen --- p.17 / Chapter 1.10. --- Secondary prevention of coronary artery disease --- p.20 / Chapter Chapter 2. --- "Heart disease, Danshen and Gegen in Chinese medicine" / Chapter 2.1. --- The record of Cardiac symptoms in Chinese Medicine --- p.24 / Chapter 2.2. --- Danshen (Salvia Miltriorrhiza) --- p.25 / Chapter 2.3. --- Gegen (Radix Pueraria) --- p.28 / Chapter Chapter 3. --- Surrogate atherosclerotic markers / Chapter 3.1. --- Flow-mediated dilatation of brachial artery (FMD) --- p.31 / Chapter 3.2. --- Carotid intima media thickness (IMT) --- p.32 / Chapter Chapter 4. --- Method / Chapter 4.1. --- Rational of the study --- p.33 / Chapter 4.2. --- Clinical protocol --- p.35 / Chapter 4.3. --- Measurement of plasma homocysteine --- p.38 / Chapter 4.4. --- Measurement of folate and vitamin B12 --- p.40 / Chapter 4.5. --- Measurement of soluble cellular adhesion molecules (CAMs) --- p.41 / Chapter 4.6. --- Measurement of plasma enterolactone --- p.43 / Chapter 4.7. --- Measurement of plasma hs-C-reactive protein --- p.44 / Chapter 4.8. --- Other laboratory tests --- p.45 / Chapter 4.9. --- High resolution ultrasound imaging --- p.46 / Chapter 4.10. --- Statistical analysis --- p.49 / Chapter 4.11. --- My contribution to this joint project --- p.49 / Chapter Chapter 5. --- Results / Chapter 5.1. --- Recruitment and outcomes of subjects --- p.51 / Chapter 5.2. --- Baseline characteristics --- p.53 / Chapter 5.3. --- Medical history and treatment received in the study subjects --- p.54 / Chapter 5.4. --- Safety profiles --- p.55 / Chapter 5.5. --- Severe adverse events --- p.56 / Chapter 5.6. --- Lipid profiles --- p.57 / Chapter 5.7. --- Secondary endpoints --- p.58 / Chapter 5.8. --- Primary endopoints --- p.59 / Chapter 5.9. --- The effect of statin usage on the primary endpoints / Chapter 5.10. --- The major determinant of the change in FMD by multivariate logistic regression / Chapter 5.11. --- Progress of lipid profiles and primary endpoints in the open label phase / Chapter Chapter 6. --- Discussion / Chapter 6.1. --- Brachial FMD --- p.66 / Chapter 6.2. --- Carotid IMT --- p.69 / Chapter 6.3. --- Brachial GTN --- p.70 / Chapter 6.4. --- Lipid-lowering effect --- p.72 / Chapter 6.5. --- Phytoestrogen --- p.72 / Chapter 6.6. --- Folate --- p.73 / Chapter 6.7. --- Vitamin B12 and glucose --- p.76 / Chapter 6.8. --- Summary of possible anti-atherogenic mechanism of D&G --- p.76 / Chapter 6.9. --- Placebo effect --- p.77 / Chapter 6.10. --- Safety profile --- p.77 / Chapter 6.11. --- Limitation of the study and suggestion of solution --- p.77 / Chapter 6.12. --- Suggestions and ummary of the future work --- p.79 / Chapter Chapter 7. --- Conclusions --- p.81 / References --- p.82
110

Avaliação de aterosclerose carotídea através de ultra-sonografia e ressonância magnética / Assessment of carotid artery atherosclerosis through ultrasound and magnetic resonance imaging

Souza, Lara Vilela de 20 April 2004 (has links)
A aterosclerose é uma doença progressiva crônica. Embora segmentar, é generalizada e acomete as artérias carótidas, propiciando maior risco de acidente vascular cerebral. Utilizamos dois métodos diagnósticos, nesta avaliação, que foram a ultra-sonografia modo B em escala de cinza associada também a fluxo Doppler colorido, e a ressonância magnética (RM) com seqüências ponderadas em T1 e T2, ambas pelas técnicas \"black-blood\" (BB) e \"fat sat black-blood\" (FSBB), e angiografia por ressonância magnética \"time-of-flight\'\' tridimensional (3D TOF), com e sem a administração do contraste paramagnético. Objetivou-se a identificação de ateromas carotídeos em pacientes coronariopatas, comprovados por cateterismo cardíaco com indicação de terapia cirúrgica. Realizou-se a estimativa do grau de estenose das artérias carótidas internas, através de ultra-sonografia com fluxo Doppler colorido (UDC) e angiografia por ressonância magnética (ARM), comparando-se os métodos. Também foram feitas comparações entre a ecogenicidade das placas visualizadas através de ultra-sonografia (USG), com a intensidade de sinal adquirida pelos exames de ressonância magnética (RM). Foi realizada avaliação de qualidade de imagens e confiabilidade inter-observadores, nos exames de ressonância magnética. Houve alta incidência de aterosclerose carotídea, nos pacientes em estudo. Do total de 100 segmentos carotídeos analisados por ultra-sonografia, com fluxo Doppler colorido para estimativa do grau de estenose, 81% apresentaram algum tipo de estenose, sendo o grau leve (grau II) predominante, evidenciado em 59% dos casos. Avaliamos a associação entre o grau de estenose visualizado através de UDC e ARM, com e sem contraste, e houve reprodutibilidade marginal entre os métodos. Observaram-se alterações de intensidade de sinal das paredes vasculares nos exames de RM, nas seqüências ponderadas em T1-BB, T1-FSBB, T2-BB e T2-FSBB, entre 71% e 72%. O aumento da intensidade de sinal foi predominante. Nas 72 placas com ecogenicidade tipo 4, houve aumento da intensidade de sinal em 13,9% em 3D TOF, 59,7% em T1-BB, 65,3% em T1-FSBB, 62,5% em T2-BB e 66,7% em T2-FSBB. Nas placas com ecogenicidade tipo 2, houve aumento da intensidade de sinal em 42,9% em 3D TOF, 71,4% em T1-BB e T1-FSBB, 85,7% em T2-BB e 71,4% em T2-FSBB. Nas placas com ecogenicidade tipo 1, houve aumento da intensidade de sinal em 50,0%, nas seqüências ponderadas em 3D TOF, T1 e T2. Em 19 segmentos carotídeos, a USG foi considerada normal. Quando os mesmos segmentos foram avaliados através de RM, observou-se aumento da intensidade de sinal em 21,1% em 3D TOF, 47,4% em T1-BB, 57,9% em T1-FSBB, 52,6% em T2-BB e T2-FSBB. Não houve correlação entre os tipos de ecogenicidade das placas visualizadas através de USG, com as alterações de intensidade de sinal pela RM. A avaliação da qualidade de imagens dos exames de RM, com cortes no plano axial nas seqüências ponderadas em T1 e T2 (BB e FSBB), foi considerada ótima e, em 3D TOF, muito boa. A qualidade de imagem dos exames de ARM, com e sem contraste, foi considerada excelente. Notou-se ótima reprodutibilidade inter-observadores, com valores de índice Kappa acima de 0,71 / Atherosclerosis is a chronic progressive disease. Although being segmental, atherosclerosis is systemic and attacks carotid arteries, propitiating a greater risk of cerebral vascular accident. In this assessment, we have applied two diagnostic imaging methods such as gray-scale B-mode ultrasound (US) in association with color flow Doppler (CFD-US) and T1 and T2-weighted magnetic resonance imaging (MRI) sequences, using black-blood (T1-BB and T2-BB) and black-blood with fat saturation (T1-FSBB and T2-FSBB) techniques, and magnetic resonance angiography (MRA) with and without paramagnetic contrast agent (three-dimensional time-of-flight, 3D TOF). Our objective was the identification of carotid atheromas in patients with coronary artery disease - as confirmed by cardiac catheterism, and referred to cardiac surgery. The degree of stenosis of the internal carotid arteries was estimated by CFD-US and by MRA, and the results from both methods were compared. The echogenicity of carotid plaques as seen by US and the signal intensity of MR images were also compared. Evaluation of image quality and inter-rater reliability of evaluation of MR images were also performed. There was a high incidence of carotid atherosclerosis in the patient population under study. From a total of one hundred (100) carotid artery segments analyzed by CFD-US for stenosis degree estimation, 81% showed some degree of stenosis, with a predominance of mild grade (grade II), which was detected in 59.0% of the cases. We have evaluated the association between the degree of stenosis visualized by CFD-US and by MRA with and without contrast agent and there was a marginal reproducibility between these methods. It was observed changes in artery wall signal intensity of 71% to 72%, in the T1-BB, T1-FSBB, T2-BB and T2-FSBB sequences of the MRI examinations. Increases in signal intensity were predominant. Among 72 plaques with echogenicity type 4, the signal intensity has increased 13.9% in 3D TOF, 59.7% inT1-BB, 65.3% in T1-FSBB, 62.5% in T2-BB and 66.7% in T2-FSBB. Among plaques with echogenicity type 2, the signal intensity has increased 42.9% in 3D TOF, 71.4% in T1-BB and T1-FSBB, 85.7% in T2-BB and 71.4% in T2-FSBB. Plaques with echogenicity type 1, showed signal intensity increase of 50.0% in the 3D TOF, T1 and T2 weighted MRI sequences. In 19 carotid artery segments, CFD-US was considered normal. When the same segments were evaluated by MRI, it was noted an increase of the image signal intensity in 21.1% in 3D TOF, 47.4% in T1-BB, 57.9% in T1-FSBB, 52.6% in T2-BB and T2-FSBB. There was no correlation between the types of plaque echogenicities seen by the CFD-US with the changes of signal intensity seen by MRI. The image quality and interobserver reliability of MR examinations were evaluated. The image quality of the T1 and T2-weighted axial MR images was considered excellent and for 3D TOF images, the quality was considered very good. The quality of the MRA images with and without paramagnetic contrast agent was considered excellent. It was noted an excellent interobserver reproducibility with values of Kappa index greater than 0.71

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