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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.
151

Intervalo de acoplamento e índice de prematuridade em cães com doença degenerativa da valva mitral e arritmias ventriculares /

Carvalho, Elizabeth Regina. January 2017 (has links)
Orientador: Marlos Gonçalves Sousa / Coorientador: Aparecido Antonio Camacho / Banca: Fernando Azadinho Rosa / Banca: Katia Mitsube Tarraga / Resumo: As arritmias ventriculares (AV) já demonstraram ser uma preocupação em cães com degeneração mixomatosa da valva mitral (DMVM). O Intervalo de acoplamento (IA) e o índice de prematuridade (IP) mostraram-se acurados em diferenciar AV benignas e malignas em seres humanos, nos quais as AV estão associadas ao maior risco no desenvolvimento de sintomas de insuficiência cardíaca e/ou morte súbita. Nesse estudo, investigamos como o IA e o IP se comportam em cães com DMVM. De forma retrospectiva e transversal, essa investigação incluiu cães com DMVM sintomática (estágios C/D; n=41), ou assintomática (estágios B1/B2; n=29), nos quais os exames eletrocardiográficos foram revisados para a mensuração do IA e do IP. Primeiramente, em oitos cães os índices obtidos tanto no Holter quanto no ECG convencional foram comparados, e não foi obtida diferença estatística entre os métodos (IA, P=0,97; IP, P=0,17). Embora o IA e o IP tenham sido determinados em todos os animais do estudo, as características dos complexos ventriculares prematuros (CVP) foram comparadas entre grupos apenas quando o registro Holter estava disponível (n=54). O IP diferiu (P=0,01) entre os cães sintomáticos (0,65 ± 0,17) e assintomáticos (0,56 ± 0,18), mas o IA foi considerado similar (P=0,91). Além disso, o grupo sintomático apresentou mais frequentemente CVP polimórficos (P=0,002) e arritmias supraventriculares (P=0,0002) do que os assintomáticos. Em conclusão, os CVP em cães com DMVM sintomática são mais prematuros, e m... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Ventricular arrhythmias (VA) were already demonstrated to be a concern in dogs with myxomatous mitral valve disease (MMVD). The coupling interval (CI) and the prematurity index (PI) were shown to accurately differentiate benign and malignant VA in human beings, in which VA are known to be associated with an increased risk to either evolve into signs of heart failure or die suddenly. In this study, we investigated how the CI and PI perform in dogs with MMVD. In a retrospective, cross-sectional investigation that included dogs with either symptomatic (stages C/D; n=41) or asymptomatic (stages B1/B2; n=29) MMVD, we reviewed the electrocardiographic tracings to calculate both the CI and PI. Firstly, in eight dogs we also compared these indices obtained from both a Holter recording and a standard ECG tracing and no statistical differences existed between methods (CI, P=0.97; PI, P=0.17). Even though CI and PI were determined in all animals enrolled in the study, ventricular premature complexes (VPC) characteristics were only compared among symptomatic and asymptomatic dogs when a Holter recording was available (n=54). The PI was different (P=0.01) between symptomatic (0.65 ± 0.17) and asymptomatic (0.56 ± 0.18) dogs, but CI was considered similar (P=0.91). Also, the symptomatic dogs had more polymorphic VPC (P=0.002) and supraventricular arrhythmias (P=0.0002) than the asymptomatic animals. In conclusion, VPC in dogs with symptomatic MMVD are more premature and more commonly associated with supraventricular arrhythmias and polymorphic ventricular premature complexes than asymptomatic animals. / Mestre
152

Performance Analysis and Optimization of 2-D Cardiac Strain Imaging for Clinical Applications

Bunting, Ethan Armel January 2017 (has links)
Heart disease has remained the deadliest disease in the United States for the past 100 years. Imaging methods are frequently employed in cardiology in order to help clinicians diagnose the specific type of heart disease and to guide treatment decisions. Ultrasound is the most frequently used imaging modality in cardiology because it is inexpensive, portable, easy to use, and extremely safe for patients. Using a variety of imaging processing techniques, deformations exhibited by the cardiac tissue during contraction can be imaged with ultrasound and used as an indicator of myocardial health. This dissertation will demonstrate the clinical implementation of two ultrasound-based strain estimation techniques developed in the Ultrasound and Elasticity Imaging Laboratory at Columbia University. Each of the two imaging methods will be tailored for clinical applications using techniques for optimal strain estimation derived from ultrasound and imaging processing theory. The motion estimation rate (MER) used for strain estimation is examined in the context of the theoretical Strain Filter and used to increase the precision of axial strain estimation. Diverging beam sequences are used to achieve full-view high MER imaging within a single heartbeat. At approximately 500 Hz, the expected elastographic signal-to-noise ratio (E(SNRe|ε)) of the axial strain becomes single-peaked, indicating an absence of “peak-hopping” errors which can severely corrupt strain estimation. In order to mediate the tradeoff in spatial resolution resulting from the use of diverging beams, coherent spatial compounding is used to increase the accuracy of the lateral strain estimation, resulting in a more physiologic strain profile. A sequence with 5 coherently compounded diverging waves is used at 500 Hz to improve the radial SNRe of the strain estimation compared to a single-source diverging sequence at 500 Hz. The first technique, Myocardial Elastography (ME), is used in conjunction with an intracardiac echocardiography (ICE) system to image the formation of thermal ablation lesions in vivo using a canine model (n=6). By comparing the systolic strain before and after the formation of a lesion, lesion maps are generated which allow for the visualization of the lesion in real-time during the procedure. A good correlation is found between the lesion maps and the actual lesion volume as measured using gross pathology (r2=0.86). The transmurality of the lesions are also shown to be in good agreement with gross pathology. Finally, the feasibility of imaging gaps between neighboring lesions is established. Lesion size and the presence of gaps have been associated with the success rate of cardiac ablation procedures, demonstrating the value of ME as a potentially useful technique for clinicians to help improve patient outcomes following ablation procedures. The second technique, Electromechanical Wave Imaging (EWI), is implemented using a transthoracic echocardiography system in a study of heart failure patients (n=16) and healthy subjects (n=4). EWI uses the transient inter-frame strains to generate maps of electromechanical activation, which are then used to distinguish heart failure patients from healthy controls (p<.05). EWI was also shown to be capable of distinguishing responders from non-responders to cardiac resynchronization therapy (CRT) on the basis of the activation time of the lateral wall. These results indicate that EWI could be used as an adjunct tool to monitor patient response to CRT, in addition to helping guide lead placement prior to device implantation.
153

Influência do tempo de exposição à fumaça de cigarro na remodelação ventricular em ratos

Castardeli, Edson [UNESP] 14 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-14Bitstream added on 2014-06-13T20:21:38Z : No. of bitstreams: 1 castardeli_e_dr_botfm.pdf: 233121 bytes, checksum: 2fe290e0c192f7cb3cf49167a9c2a189 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O efeito da exposição à fumaça de cigarro (EFC) tem sido extensivamente estudado; entretanto, os efeitos diretos cardíacos da fumaça de cigarro despertam menos atenção. O objetivo deste estudo foi determinar as alterações cardíacas estruturais e funcionais causadas pela EFC, em ratos e, analisar a influência do tempo de EFC na remodelação ventricular. Material e método Ratos Wistar adultos foram alocados em dois grupos: controle (C, n=43), subdividido em dois grupos, controle dois meses (C2, n=25), controle seis meses (C6, n=18) e grupo fumante (F, n=47), igualmente, subdivididos em dois grupos, fumante dois meses (F2, n=22) e fumante seis meses (F6, n=25), que foram expostos à fumaça de cigarro, respectivamente por períodos de dois e seis meses. Todos os animais foram pesados e tiveram mensurado na cauda a pressão arterial sistólica (PAS). A função cardíaca foi estudada pelo método ecocardiográfico (in vivo) e pelo método do coração isolado (in vitro) contraindo isovolumetricamente. Resultados Não houve diferença significante no peso do corpo (PC) entre os grupos controle e fumante. Foram observados valores maiores para o átrio esquerdo (AE), com p=0,005, entre os grupos C e o grupo F, para o AE, corrigido pelo peso do corpo (AE/PC), com p=0,001 e índice de massa do ventrículo esquerdo (IMVE), com p=0,048. Foi observada interação estatística significante para o diâmetro diastólico do ventrículo esquerdo (DDVE), corrigido pelo peso do corpo dos animais (DDVE/PC), com diferença (p=0,023) entre o grupo C e o grupo F, também, com diferença (p=0,048) entre o grupo dois meses e o grupo seis meses e valores diferentemente (p=0,010) entre fumantes e o tempo de exposição ao fumo. Para PAS, foi observada diferença significante na análise da PAS caudal nos grupos C2 e C6 (valores menores) em comparação... / The vascular effects of exposure to smoke of cigarettes have been extensively studied; however, the cardiac effects of tobacco smoke deserved less attention. The aim of this study was to determine the cardiac structural and functional alterations caused by cigarette smoke exposure in rats and analyse the influence to time of exposure to smoke of cigarettes in remodeling ventricular. Material and Methods - Adult Wistar rats were allocated into two groups: control (C, n=43), separated into two sub-groups, two months control (C2, n=25), six months control (C6, n=18) and exposed to tobacco smoke (S, n=47), equally, separated in two sub-groups, two months exposed to tobacco smoke (S2, n=22) and six months exposed to tobacco smoke (S6, n=25), repectively per period into two months and six month. All animals were weighed and had the tail cuff systolic arterial pressure (SAP) measured. The cardiac function was studied study by echocardiogram method (in vivo) and by isolated isovolumetrically beating heart method (in vitro). Results - There was no significant difference in body weight (BW) between groups control and exposed to tobacco smoke. Higher values were found for left atrium (LA), with p=0,005, between groups C and grup S, by LA, adjusted for BW, with p=0,001 and left ventricular mass index, with p=0,048. There was statistically significant interaction by left ventricular diastolic diameter (LVDD), adjusted for BW into animals (LVDD/BW), with difference significant (p=0,023) between group C e o group F, also, with difference (p=0,048) between group two months and o grupo six months and, values differently (p=0,010) between smoking and exposure to tobacco load. There was systolic arterial pressure (SAP), to the difference significant the... (Complete abstract click electronic access below)
154

Predicting the psychological and physiological prognosis of cardiac rehabilitation patients

Feldner-Busztin, Adrienne January 1995 (has links)
Thesis submitted to the Faculty of Arts, University of the Witwatersrand, for the degree of Doctor of Philosophy Johannesburg 1995 / The large percentage of deaths attributed to recurrent Coronary Heart Disease (CHD) has generated a search for behavioural and psychological factors which mitigate the consequences of CHD. An aim of the present thesis is to extend this search by identifying factors which predict prognosis fer recovery from CHD. Two key factors seen to influence prognosis are aerobic exercise and Type A behaviour. Extant research into the role of exercise has been hindered by methodological weaknesses. As a consequence, the precise means by which exercise influences CHD patients' psychological and physiological strain remains unclear. Similarly, the Type A literature has been flawed by the inaccurate conceptualisation and measurement of Type A behaviour as a global, and 110t a multidimensional, construct. Research which has examined the multidimensional nature of Type A behaviour has been restricted to low risk samples. Thus, a further aim. of the present research is to examine ; prognostic role of exercise and Type A components within the context of cardiac rehabilitation. In achieving this aim, three studies are conducted. [Abbreviated Abstract. Open document to view full version] / MT2017
155

Avaliação da prevalência de sintomas gastrointestinais e cardiovasculares em trabalhadores rurais expostos e não expostos à agrotóxicos no Vale de Cuncas, Barro-CE / Evaluation of reffered morbidity prevalence in rural workers exposed to agrotoxics in the valley of cuncas, barro-CE

Oliveira, Luciano Braga de 29 March 2017 (has links)
Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2017-08-05T13:12:51Z No. of bitstreams: 1 Luciano Braga de Oliveira.pdf: 2158750 bytes, checksum: 781582f0d9ba1728d24ccfd5b4927041 (MD5) / Made available in DSpace on 2017-08-05T13:12:51Z (GMT). No. of bitstreams: 1 Luciano Braga de Oliveira.pdf: 2158750 bytes, checksum: 781582f0d9ba1728d24ccfd5b4927041 (MD5) Previous issue date: 2017-03-29 / INTRODUCTION: The economic growth turned Brazil into one of the greatest agrochemicals consumers in the world. However, there were few studies that analyzed agricultural workers health exposure. OBJECTIVE: Evaluate the prevalence of cardiovascular symptoms on tomato rural workers (GE) exposed to agrochemicals in the Cuncas Valley, Barro ¿ CE. METHODS: A cross-sectional study questionnaire was applied to 50 tomato rural workers (GE), aged at least 18 years old, in their work place. A control group was selected from the not exposed population (GNE) paired by gender and age. It was used two questionnaires: a bio demographical, in order to analyze the schooling, income, marital status, residence type, medications and cardiovascular symptoms; and a protocol questionnaire about agrochemicals health effects to verify preparation steps, application, packaging destination, work clothes, use of Individual Protection Equipment (IPEs), perception and search for health services (hospitals or health basic units) in case of health alterations after agrochemicals application. It was applied a descriptive analysis, chi-square test, two proportion test and a logistic regression. The significant level was 5%. RESULTS: The exposed mean age was 41.42 (sd=10.50), and for the non-exposed group was 42.42 (sd=15.91). Ninety four percent was male, with some schooling. In the exposed group all tomato workers used agrochemicals, 66% not differ the toxicological products classification, only 22% read the packages. In relation to the agrochemicals, the same group, 94% used according to the recommended measures, 76% used daily, 98% used manual application and 78% avoid agrochemical overdose. Workers exposed to the agrochemicals presented more irritability (p<0.001), mental confusion (p=0.001), shortness of breath (p=0.003), sweating (p=0.008), dizziness (p=0.046), and headache (p=0.047). Rural workers exposed to agrochemicals had more chance to have a stomachache (RP=3.92, CI95%: 1.01 ¿ 15.22), chest pain (RP=5.33, CI95%: 1.68 ¿ 16.97), tachycardia (RP=4.48, CI95%: 1.34 ¿ 14.24), palpitation (RP=3.53, CI95%: 1.05 ¿ 11.86) and hypertension (RP=5.18, CI95%: 1.53 ¿ 17.99) when compared to the non-exposed group. In the exposed group the workers who did not give particular attention to clothes had more chance to developed hypertension (RP=5.70, CI95%: 1.01 ¿ 33.27) and cardiovascular disease (RP=5.40, CI95%: 1.01 ¿ 30.17). CONCLUSION: Exposure to agrochemicals affected the cardiovascular and gastric health system. / INTRODUÇÃO: O Brasil é um dos maiores consumidores de agrotóxico do mundo, devido ao crescimento econômico. No entanto, existem poucos estudos que avaliam os efeitos dos agrotóxicos nos trabalhadores rurais. OBJETIVO: Avaliar a prevalência dos sintomas cardiovasculares nos trabalhadores rurais da cultura do tomate expostos (GE) ao agrotóxico no vale de Cuncas, Barro ¿ CE. MÉTODO: Foi realizado um estudo de corte transversal através da aplicação de questionário no local de trabalho com todos os trabalhadores da cultura de tomate (50 trabalhadores), como critério de inclusão temos maiores de 18 anos idade. E um grupo controle a partir população não exposta (GNE) pareado por sexo e idade. Foram utilizados dois questionários: um biodemográfico cujas questões quanto ao sexo, idade, grau de escolaridade, renda familiar, situação conjugal, tipo de residência, medicamento e sintomas cardiovasculares. E outro questionário do protocolo sobre o efeito do agrotóxico na saúde, como os modos de preparo, aplicação e a destinação das embalagens, uso dos EPIs, percepção e busca aos serviços de saúde ¿ postos de saúde e/ou hospitais ¿ por alguma alteração após aplicação do agrotóxico. Foi realizada a análise descritiva, testes de Qui-quadrado e/ou exato de Fisher, de comparação entre duas porcentagens, e a regressão logística. O nível de significância foi de 5%. RESULTADOS: A população estudada tem uma idade média de 41,42 anos (DP ±10,50) para os expostos e 42,42 anos (DP ±15,91) para os não expostos. 94,0% é do sexo masculino, e com algum tipo de escolaridade. No grupo expostos todos utilizam o agrotóxico, 66,0% não diferenciam a classificação toxicológica dos produtos, 22,0% leem as embalagens. Possuem conhecimentos de manejo pois 94,0% sempre usa a quantidade recomendada, com uso diário em 76,0% do universo e 78,0% evitam a superdosagem e de aplicação manual para 98,0%. Em relação aos efeitos dos agrotóxicos apresentam maior irritabilidade (p=0,000), confusão mental (p=0,001), sudorese (p=0,008), tontura (p=0,046) e cefaleia (p=0,047). Os trabalhadores expostos ao agrotóxico apresentaram maior chance para dor no estômago (RP = 3,92, IC95%: 1,01 - 15,22), dor torácica (RP = 5,33; IC95%: 1,68-16,97), taquicardia (RP = 4,48, IC95% 1,34 - 14,24), palpitações (RP = 3,53, IC95%: 1,05 - 11,86) e hipertensão (RP = 5,18, IC95%: 1,53 - 17,99), quando comparado ao grupo não exposto. No grupo exposto que não deu atenção especial as roupas, os trabalhadores apresentaram mais chance de desenvolver hipertensão (RP = 5,70, IC95%: 1,01 - 33,27) e doença cardiovascular (RP = 5,40, IC95%: 1,01 - 30,17). CONCLUSÃO: A exposição aos agroquímicos afetou o sistema de saúde gástrico e cardiovascular.
156

Relação entre poluição do ar e internações por doenças isquêmicas no coração, em adultos, na Cidade de São Paulo, estratificado por sexo, explorando estruturas de defasagens, para o período de 2000 a 2013

Freitas, Francisco Orlando Rafael 10 April 2017 (has links)
Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2017-08-22T18:44:23Z No. of bitstreams: 1 Francisco Orlando Rafael Freitas.pdf: 3156371 bytes, checksum: 890fc3eea1e863771fa92f290802cb73 (MD5) / Made available in DSpace on 2017-08-22T18:44:23Z (GMT). No. of bitstreams: 1 Francisco Orlando Rafael Freitas.pdf: 3156371 bytes, checksum: 890fc3eea1e863771fa92f290802cb73 (MD5) Previous issue date: 2017-04-10 / The aim of this study was to evaluate the relationship between air pollution and adults ischemic heart disease admissions (IHD) in São Paulo city, stratified by gender, exploring lag structures for the period from 2000 to 2013. The is an ecological time series study. The data referring to O3, PM10, CO, SO2, NO2, minimum temperature and humidity were obtained from the Environmental Company of São Paulo State (CETESB). Hospital admissions were obtained from the Public Health System database (DATASUS). It was used the descriptive analysis and Generalized linear model of Poisson regression with third-degree polynomials, considering a distributed lag of up to seven days after exposure as well as controlling for long-term seasonality, weekdays. The significant level was 5%. For an interquartile range increase in PM10 (24.29¿g/m³) no significant effects were observed for the age group 30 to 44. But for the age group 45 to 60, there was an increase due to men admissions for 3.30% (95% CI: 1.64-4.96) and for females 2.88% (95% CI: 1.42-4.33) on the day of exposure. An interquartile range increase in SO2 (7.63 ¿g / m³), there was an increase of 6.99% (95% CI: 3.31-10.67) and 2.46% (95% CI: 0 , 51-4,42) on the day and the day after of exposure in the age group 30 to 44, and an increase of 3.91% (95% CI: 2.38-5.44) and 1.92% (95% CI: 1.10-2.73) in the age group 45 to 60. For NO2, an interquartile range (50.22 ¿g / m³) increases the total admissions in 6.17% (95% CI: 2.80-9.53) on the day of exposure, demonstrating acute effect. Ischemic heart diseases present an acute effect on people exposure to air pollutants, affecting both gender in the age groups. It is important the implementation of public policies aiming at levels of concentrations that do not affect the population health. / Este estudo tem por objetivo avaliar a relação entre poluição do ar e internações por doenças isquêmicas do coração (DIC), em adultos, na cidade de São Paulo, estratificada por sexo, explorando estruturas de defasagens, para o período de 2000 a 2013. O presente estudo é ecológico de séries temporais, no qual as análises foram estratificadas por faixa etária e sexo e incluíram internações por Doenças Isquêmicas do Coração (CID10: I50). Os dados referentes O3, PM10, CO, SO2, NO2, temperatura mínima e umidade foram obtidos da Companhia Ambiental do Estado de São Paulo (CETESB), já as internações hospitalares foram obtidas a partir do banco de dados do SUS (DATASUS). A relação entre poluentes do ar e fatores climáticos nas internações por doenças isquêmicas do coração foram analisadas por meio de um modelo de defasagem de distribuição polinomial tanto para a temperatura como para os poluentes do ar. Foi utilizado o modelo linear generalizado de regressão de Poisson com polinômio de terceiro grau e considerando uma defasagem distribuída de até sete dias após a exposição como também, controlando-se para sazonalidade de longa duração, dias da semana e feriados. A seguir, foi calculado o aumento no número de internações para a diferença interquartil dos poluentes significativos no modelo de regressão, bem como para os fatores meteorológicos. Verificou-se que o O3 não teve relação a todos os desfechos analisados. Para um aumento de interquartil de PM10 (24,29¿g/m³) não foi evidenciado efeito significativo pós-exposição entre 30 a 44 anos. Já para faixa etária de 45 a 60 anos, com aumento de um interquartil de PM10 houve elevação nas internações de homens por doença isquêmica do coração de 3,30% (IC95%: 1,64-4,96) e para o sexo feminino de 2,88% (IC95%: 1,42-4,33) no dia da exposição. Para as internações totais, com aumento de um interquartil (7,63 ¿g/m³) de SO2, houve elevação de 6,99% (IC95%: 3,31-10,67) e 2,46% (IC95%: 0,51-4,42) nas internações no dia da exposição e no dia seguinte referente a faixa etária de 30 a 44 anos e aumento de 3,91% (IC95%: 2,38-5,44) e 1,92% (IC95%: 1,10-2,73) para faixa etária de 45 a 60 anos. Referente ao NO2, uma variação interquartil (50,22 ¿g/m³) aumentou 6,17% (IC95%: 2,80-9,53) nas internações totais apenas no dia da exposição demonstrando efeito agudo. Com o aumento de um interquartil na concentração de CO igual a 1,28 ppm não foi evidenciado elevação das internações por DIC com relação a faixa etária e gênero/sexo. Diante do exposto, verifica-se que as Doenças Isquêmicas do coração apresentam efeito agudo a exposição aos poluentes do ar e aos fatores meteorológicos, afetando o sexo masculino e feminino nas faixas etárias estudadas, com isso evidencia-se a importância das políticas públicas voltadas para manutenção dos níveis de poluentes em concentrações que não afetem a saúde da população.
157

Tricuspid valve mechanics: understanding the effect of annular dilatation and papillary muscle displacement

Spinner, Erin M. 28 July 2011 (has links)
Tricuspid regurgitation (TR), back flow of blood from the right ventricle to the right atrium, has been reported in approximately 85% of the population, with 16% having mild or severe TR. Patients with untreated moderate to severe TR are likely to experience decreased exercise capacity and have increased morbidity and mortality, thus affecting the patient's quality of life. Current methods of repair offer limited rates of success, and many patients require further operations to correct returning levels of TR. Incomplete repair may be due to incomplete understanding of the functional anatomy and mechanics of the TV and the underlying causes of TR. It was hypothesized that alterations in the geometry of tricuspid valve annular and subvalvular apparatus induced by ventricular dilatation determine the severity of TR. In vivo measurements of papillary muscle (PM) position in patients with single or biventricular dilatation revealed PM displacement away from the center of the annulus as compared to control patients. Additionally, pulmonary arterial pressure, annulus area, ventricular size and apical displacement of the anterior PM were highly correlated with the severity of TR. An in vitro right-heart simulator was developed to investigate isolated mechanics of TR. Through these in vitro studies it was demonstrated that the tricuspid valve begins to leak at only 40% dilation, much lower than the mitral valve. Additionally, it was shown that isolated PM displacement resulted in significant TR. The highest levels of TR were achieved with a combination of annular dilatation and PM displacement. Alterations in leaflet coaptation, as quantified by measuring the amount of leaflet available for coaptation and leaflet mobility were observed with annular dilatation and PM displacement, both isolated and combined. The changes in leaflet coaptation resulted in redistribution of the forces on the chords originating from the anterior PM and inserting into the anterior and posterior leaflets. The findings herein provide the clinical and scientific community with a mechanistic understanding of the tricuspid valve to further improve intervention and repair of TV disease.
158

Endocarditis crónica

Escarrá i Janer, Agustí 30 June 1893 (has links)
Barcelona : Impr. universal de Juan Bautista Llop, 1893 / “En el estudio de las ciencias biológicas, como en el de las eminentemente prácticas, debe de relegarse á un lugar muy secundario y sospechoso todo cuanto no sea hijo legítimo de la más concienzuda experimentación (…) Cualquiera cuestión técnica expuesta en el seno de las doctas corporaciones, como cualquier hecho insólito de carácter epidémico que azote á las multitudes, es pretexto abonado para suscitar debates y pareceres, que se caracterizarán, no por tener una misma unidad de miras, no por correr parejas con un racional criterio, pero sí por ser tantos en número cuantas sean las individualidades lanzadas impremeditadamente al palenque. Que los médicos tengan opiniones, es muy natural y viejo; que ellas son múltiples y exajeradas, tampoco es nuevo; pero que sean encontradas y en su mayoría opuestas, es cosa muy lamentable. El médico joven que consagra toda su atención a los problemas científicos, hasta el punto de convertirse en su propio esclavo, cae en un mar de confusiones siempre que aquéllos se refieren á casos por él no vistos ni comprobados en las salas del Hospital; las mil y una soluciones que á dichos problemas se dan, acaban por trocar su entusiasmo científico por el más cruel de los excepticismos (…)Para no concurrir, pues, con un nuevo grano de arena á engrosar esos inconmensurables obstáculos, y para no incurrir en el delito de una innovación no consolidada por los méritos que son menester, nos decidimos á desenvolver nuestro trabajo reglamentario bajo un tema que podrá no suscitar grandes polémicas, ni predisponer á la divagación de ideas, no ser pródigo en emociones y sorpresas, pero cuya capitalísima y escepcional importancia tiene en su favor los sufragios de aquellos á quienes no se les oculta la gran utilidad que á muchos prácticos pudiera reportar una recopilación de las endocarditis crónicas en un solo capítulo, redactado con estilo sencillo, dispuesto con un plan y método lo más claros posible, consagrado sólo á lo decisivo y concluyente, y ajeno á los detalles supérfluos y á las ampulosidades de relumbrón, que siempre han de redundar en menoscabo de la sencillez, concisión y claridad de que tanto necesitan las cuestiones teórico-prácticas, Esto es lo que nosotros nos hemos propuesto; pero ¿nos ha sido dable conseguirlo en todos sus puntos? Juzgue y dígalo el doctísimo cuanto respetable tribunal”.
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Psychological factors associated with walking in patients with Peripheral Arterial Disease

Cunningham, Margaret January 2010 (has links)
Objectives This thesis aimed to explore psychological factors associated with walking behaviour in patients with Peripheral Arterial Disease, within the framework of Leventhal et al’s (1998) Common-sense Model of Self-regulation of Health and Illness. The objective was to identify psychological factors which could be modified to increase walking behaviour in these patients. Method A series of three studies were conducted to achieve these aims. The first study was an exploratory qualitative study, to explore the illness and treatment beliefs and walking behaviour of patients with intermittent claudication. The second study was a cross-sectional postal questionnaire to a cohort of patients with intermittent claudication, which tested the influence of the psychological factors identified in the qualitative study, in a larger sample. The final study was a randomised controlled trial of a brief psychological intervention designed to modify the illness and walking beliefs of patients with intermittent claudication, in order to increase walking behaviour. Results Beliefs about intermittent claudication, and beliefs about walking were both found to be associated with walking behaviour in the qualitative study. The results from the cross-sectional postal questionnaire confirmed this relationship – taken as a set, illness and walking beliefs accurately predicted adherence to minimum walking levels for 93.4% of the sample. The brief psychological intervention successfully modified illness and treatment beliefs and increased walking behaviour in patients newly diagnosed with intermittent claudication. Conclusion This thesis highlights the importance of illness and walking beliefs to the walking behaviour of patients with intermittent claudication. The thesis has added to the body of knowledge about intermittent claudication, and the findings of this thesis have implications for the treatment of patients with intermittent claudication within the health service. Theoretical and clinical implications of this research are discussed.
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Effect of cardiac rehabilitation on vascular function in patients withcoronary artery disease

Luk, Ting-hin., 陸庭軒. January 2010 (has links)
published_or_final_version / Medicine / Master / Master of Research in Medicine

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