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Ecocardiografia como auxílio didático no estudo da morfologia, fisiologia e fisiopatologia do coração na hipertensão arterial / Echocardiography as a teaching aid in the study of the morphology, physiology and pathophysiology of heart in hypertensionSegamarchi, Fábio Abdalla 19 June 2013 (has links)
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Previous issue date: 2013-06-19 / Hypertension is a disease of high prevalence, oligosymptomatic, with low rates of blood pressure control and with serious consequences if not treated properly. The involvement of target organs can lead to serious restrictions in the quality of life on affected individuals, high financial costs to society and the public health system on Brazil (Sistema Único de Saúde). Echocardiography has an important role in risk stratification and clinical management of these patients. Moreover, the exam allows to visualize the structure and the functional characteristics of the heart, which can be an additional tool for teaching students and health professionals in training. The use of educational software in the medical field provides an interactive and autonomy learning. Objective: To use the images of echocardiography to develop software that will apply as a tool for the education of student health, allowing comprehend of normal cardiac structure and function and the heart compromised by hypertension. The secondary objective was to evaluate the software using qualitative and quantitative tools, including opinions and suggestions of students of medicine and nursing. Hypothesis: The use of the software can make teaching more attractive, agile and appropriate to communication technologies and contemporary education and allow the user to understand the real consequences of hypertension on the heart. Methodology: The software was developed from the author's own database of images using the author multimedia Flash® which allows the creation of animations and simulations in vector language, resulting in compact files that can be made available through the Web or on optical and magnetic media. The evaluation of the final product was made by students of medicine and nursing. Results: The software was well evaluated by students of medicine (n = 38) and nurses (n = 18) of the Faculdade de Ciências Médicas e da Saúde da PUC/SP, whose pre and post-tests of the material showed consistent growth of knowledge, either through self-assessment or objective open questions. Conclusion: The software using the echocardiography was effective in making easier the understanding of the impact caused by hypertension in the heart, in view of the complexity of educational content. The software can be useful to students, teachers and professionals in the health field / A hipertensão arterial é uma doença de alta prevalência, oligossintomática, com baixo nível de controle pressórico e com consequências graves quando não tratada de maneira adequada. O acometimento de órgãos-alvo pode levar a sérias restrições na qualidade de vida dos indivíduos acometidos, altos custos financeiros para a sociedade e o Sistema Único de Saúde. A avaliação das repercussões cardíacas pela ecocardiografia tem importante papel na estratificação de risco e condução clínica desses pacientes. Além disso, o exame permite visualizar a estrutura e as características funcionais do coração, podendo ser um instrumento adicional para o ensino do comprometimento cardíaco a estudantes e profissionais da área da saúde em formação. O uso de softwares educacionais na área médica proporciona um aprendizado interativo e com autonomia, cujo principal benefício é o respeito ao ritmo de aprendizado de cada usuário.
Objetivo: utilizar as imagens do exame ecocardiográfico para desenvolver um software que servirá como ferramenta na educação e capacitação dos estudantes da área da saúde, permitindo a compreensão da estrutura e função cardíacas normais e comprometidas pela hipertensão arterial. O objetivo secundário foi avaliar o software utilizando instrumentos qualitativos e quantitativos, incluindo opiniões e sugestões de estudantes de medicina e enfermagem.
Hipótese: a utilização do software pode tornar o ensino mais atraente, ágil e adequado às tecnologias de comunicação e educação contemporâneas e permitirá ao usuário compreender as reais consequências da hipertensão arterial sobre o coração.
Metodologia: O software foi desenvolvido a partir de um banco de imagens do próprio autor utilizando o autor de multimídia Flash®, que permite a elaboração de animações e simulações em linguagem vetorial, resultando em arquivos compactos que podem ser disponibilizados através da Web ou em mídias ópticas e magnéticas. A avaliação do produto final foi feita por estudantes de medicina e enfermagem.
Resultados: O software foi concluído e bem avaliado pelos estudantes do curso de medicina (n=38) e enfermagem (n=18) da Faculdade de Ciências Médicas e da Saúde da PUC/SP, cujos testes realizados pré-utilização e pós-utilização do material, mostrou consistente crescimento do conhecimento, seja por auto-avaliação ou por questões objetivas abertas.
Conclusão: O software utilizando a ecocardiografia mostrou-se eficiente em facilitar o entendimento das repercussões causadas pela hipertensão arterial no coração, tendo em vista a complexidade deste conteúdo didático. O software poderá ser útil a estudantes, profissionais e docentes da área da saúde
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Estudo da reserva de perfusão miocárdica pelo ecocardiograma com contraste em tempo real, em indivíduos com hipercolesterolemia grave, antes e após tratamento com inibidores da HMG-CoA redutase / Evaluation of myocardial perfusion reserve in severe hypercholesterolemic patients with real time contrast echocardiography, before and after treatment with HMG-CoA reductase inhibitorsLario, Fábio de Cerqueira 02 June 2009 (has links)
INTRODUÇÃO: A hipercolesterolemia provoca alterações inflamatórias no sistema cardiovascular, induzindo disfunção endotelial e mudanças estruturais na microcirculação, com alterações significativas da homeostase vascular, processo este reversível com o tratamento hipolipemiante. Clinicamente, tais fenômenos podem ser demonstrados pela avaliação da reserva de fluxo coronário e da reatividade vascular periférica. A ecocardiografia de perfusão miocárdica em tempo real (EPMTR) possui características que a tornam ideal para a avaliação da microcirculação coronária, como a utilização de contrastes intravasculares, além de ótimas resoluções temporal e espacial. MÉTODOS: 16 pacientes com hipercolesterolemia e sem lesões coronárias obstrutivas (grupo HF) e 10 indivíduos saudáveis, sem doença arterial coronária obstrutiva estabelecida (grupo controle) foram avaliados por EPMTR e por ultrassonografia da artéria braquial em dois momentos: pré-tratamento com atorvastatina no grupo HF (período livre de medicação >6 semanas) e 12 semanas após o primeiro exame. A análise do fluxo miocárdico foi realizada nos 17 segmentos do ventrículo esquerdo obtendo-se índices de volume de sangue relativo no miocárdio (AN), da velocidade do fluxo () e do fluxo miocárdico absoluto (ANx) na condição de repouso e durante a vasodilatação com adenosina. A reserva de fluxo foi definida como a razão entre o fluxo durante vasodilatação e o fluxo do repouso. Para estudo da reatividade vascular periférica, todos os indivíduos foram submetidos à ultrassonografia da artéria braquial, com avaliação dos diâmetros da artéria braquial antes e depois de um período de isquemia de 5 minutos. RESULTADOS: Os dois grupos foram comparáveis quanto à idade, sexo, peso, superfície corpórea, índice de massa corpórea, índice de massa do VE, frequência cardíaca e pressões arteriais sistólica e diastólica, tanto no repouso quanto durante a infusão de adenosina. Os valores evolutivos de LDL-C (mg.dL-1) nos dois momentos foram 106±36 e 107±35; p=NS para o grupo controle vs 278±48 e 172±71; p<0,001 para o grupo HF. Na avaliação inicial, a dilatação braquial estava reduzida nos pacientes do grupo HF 0,08±0,04 vs 0,15±0,02; p<0,001 relativamente ao grupo controle, com aumento do diâmetro arterial basal (mm): 3,42±0,63 vs 3,07±0,53; p<0,001. O grupo HF, quando comparado ao grupo controle na avaliação inicial, apresentava valores mais altos de AN: (dB) 0,56±0,08 vs 0,49±0,05; p=0,02, de (s-1) 0,56±0,14 vs 0,45±0,04; p=0,02 e ANx: (dB.dB-1 s-1) 0,28±0,06 vs 0,20±0,02; p<0,001, maiores valores de AN: durante infusão de adenosina 0,64±0,08 vs 0,57±0,06; p=0,001 e menores reservas de : 2,59±0,61 vs 3,25±0,45; p=0,001 e de ANx: 2,78±0,71 vs 3,43±0,66; p=0,03. Após o uso de atorvastatina, as alterações foram revertidas, tanto na circulação periférica quanto na coronária. CONCLUSÕES: A EPMTR monstrou que em indivíduos com hipercolesterolemia e sem doença coronária obstrutiva existe aumento do fluxo microvascular em repouso e redução da reserva de fluxo miocárdico. Após o tratamento com atorvastatina houve normalização do fluxo em repouso. Adicionalmente, alterações similares ocorreram na circulação periférica dos indivíduos hipercolesterolêmicos, revertidas por utilização da atorvastatina. / BACKGROUND: Hypercholesterolemia induces inflammatory changes on the cardiovascular system, causing endothelial dysfunction and structural alterations of microcirculation, with substantial imbalance of vascular homeostasis. Reduction of blood cholesterol levels can stop these processes. These circulation alterations can be demonstrated by coronary flow reserve and peripheral vascular reactivity evaluation. Real time myocardial perfusion echocardiography (EPMTR) is an excellent method to demonstrate coronary microcirculation alterations, as ultrasound contrast agent has rheological properties close to red cells. Additionally, EPMTR has optimal spatial and temporal resolutions. METHODS: 16 patients with hypercholesterolemia (group-HF) without overt obstructive coronary disease and 10 healthy volunteers (group-C) were evaluated by EPMTR and vascular ultrasound in 2 moments: before atorvastatin treatment (group-HF, >6 weeks free of statin) and 12 weeks after beginning medication (group-HF), or 12 weeks after the first evaluation (group-C). For myocardial blood flow evaluation, the left ventricle was divided into 17 segments, and indexes of myocardial blood volume (AN), blood flow velocity (), and myocardial blood flow (ANx) were obtained for each myocardial segment at rest condition and after adenosine infusion. Myocardial flow reserve was calculated as the hyperemic to rest values of AN, e ANx. Peripheral vascular reactivity was evaluated by vascular ultrasound. Measures of braquial artery diameter were obtained before and after 5 minutes of arterial flow occlusion. RESULTS: Both groups were comparable for age, sex, body weight, body surface area, body mass index, left ventricular mass index, heart rate, and systolic and diastolic arterial blood pressure. These variables were also comparable, under basal or adenosine stress conditions. LDL-C values (mg.dL-1) in different moments (intra-group) were 106±36 and 107±35; p=NS for group-C vs 278±48 and 172±71; p<0,001 for group-HF. Group-HF as compared to group-C had higher initial resting values of AN (dB): 0,56±0,08 vs 0,49±0,05; p=0,02, (s-1): 0,56±0,14 vs 0,45±0,04; p=0,02, and ANx (dBdB-1s-1): 0,28±0,06 vs 0,20±0,02; p<0,001, and higher hyperemic value of AN 0,64±0,08 vs 0,57±0,06; p=0,04, and lesser reserves of 2,59±0,61 vs 3,25±0,45; p=0,01 and of ANx: 2,78±0,71 vs 3,43±0,66; p=0,03. After atorvastatin treatment no difference was observed at rest, hyperemic and reserve values of AN, and ANx between the groups. CONCLUSION: In patients with hypercholesterolemia and without coronary obstruction, there was augmented myocardial blood flow and reduced coronary flow reserve at rest, compared to healthy volunteers. After atorvastatin treatment at rest myocardial blood flow was normalized in those patients. Additionally, similar alterations in peripheral circulation could be demonstrated in hypercholesterolemia, and were reverted with atorvastatin.
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Papel do ecocardiograma transesofágico tridimensional na ótima seleção do dispositivo para o tratamento percutâneo da comunicação interatrial tipo ostium secundum / Role of three-dimensional transesophageal echocardiography in optimal device selection for percutaneous treatment of the ostium secundum atrial septal defectArrieta, Santiago Raul 19 May 2015 (has links)
INTRODUCAO: A comunicação interatrial tipo \"ostium secundum\" é um defeito cardíaco congênito caracterizado pela deficiência parcial ou total da lâmina da fossa oval, também chamada de septo primo. Corresponde a 10 a 12% do total de cardiopatias congênitas, sendo a mais frequente na idade adulta. Atualmente a oclusão percutânea é o método terapêutico de escolha em defeitos com características anatômicas favoráveis para o implante de próteses na maioria dos grandes centros mundiais. A ecocardiografia transesofágica bidimensional com mapeamento de fluxo em cores é considerada a ferramenta padrão-ouro para a avaliação anatômica e monitoração durante do procedimento, sendo crucial para a ótima seleção do dispositivo. Neste sentido, um balão medidor é introduzido e insuflado através do defeito de forma a ocluí-lo temporariamente. A medida da cintura que se visualiza no balão (diâmetro estirado) é utilizada como referência para a escolha do tamanho da prótese. Recentemente a ecocardiografia tridimensional transesofágica em tempo real tem sido utilizada neste tipo de intervenção percutânea. Neste estudo avaliamos o papel da mesma na ótima seleção do dispositivo levando-se em consideração as dimensões e a geometria do defeito e a espessura das bordas do septo interatrial. METODO: Estudo observacional, prospectivo, não randomizado, de único braço, de uma coorte de 33 pacientes adultos portadores de comunicação interatrial submetidos a fechamento percutâneo utilizando dispositivo de nitinol autocentrável (Cera ®, Lifetech Scientific, Shenzhen, China). Foram analisadas as medidas do maior e menor diâmetro do defeito, sua área e as medidas do diâmetro estirado com balão medidor obtidas por meio das duas modalidades ecocardiográficas. Os defeitos foram considerados como elípticos ou circulares segundo a sua geometria; as bordas ao redor da comunicação foram consideradas espessas (>2 mm) ou finas. O dispositivo selecionado foi igual ou ate 2 mm maior que o diâmetro estirado na ecocardiografia transesofágica bidimensional (padrão-ouro). Na tentativa de identificar uma variável que pudesse substituir o diâmetro estirado do balão para a ótima escolha do dispositivo uma série de correlações lineares foram realizadas. RESULTADOS: A idade e peso médio foram de 42,1 ± 14,9 anos e 66,0 ± 9,4kg, respectivamente; sendo 22 de sexo feminino. Não houve diferenças estatísticas entre os diâmetros maior e menor ou no diâmetro estirado dos defeitos determinados por ambas as modalidades ecocardiográficas. A correlação entre as medidas obtidas com ambos os métodos foi ótima (r > 0,90). O maior diâmetro do defeito, obtido à ecoardiografia transesofágica tridimensional, foi a variável com melhor correlação com o tamanho do dispositivo selecionado no grupo como um todo (r= 0,89) e, especialmente, nos subgrupos com geometria elíptica (r= 0,96) e com bordas espessas ao redor do defeito (r= 0,96). CONCLUSÃO: Neste estudo em adultos com comunicações interatriais tipo ostium secundum submetidos à oclusão percutânea com a prótese Cera ®, a ótima seleção do dispositivo pôde ser realizada utilizando-se apenas a maior medida do defeito obtida na ecocardiografia transesofágica tridimensional em tempo real, especialmente nos pacientes com defeitos elípticos e com bordas espessas. / INTRODUCTION: The ostium secundum atrial septal defect is a congenital heart disease characterized by partial or total deficiency of the fossa ovalis, also known as the septum primum. It corresponds to 10-12% of all congenital heart defects, being the most frequently found in adulthood. Currently, percutaneous closure is the therapeutic method of choice for defects with suitable anatomic features for device implantation in most centers in the world. Bi-dimensional transesophageal echocardiography with color flow mapping is considered the gold-standard tool for anatomic assessment and procedural monitoring, being crucial for optimal device selection. In this regard, a sizing balloon is introduced and inflated across the defect with temporary occlusion. The waist measurement seen on the balloon (stretched diameter) is used as a reference for selection of device size. Recently, real time three-dimensional transesophageal echocardiography has been utilized in this type of percutaneous intervention. In this study we assessed the role of this modality in optimal device selection taking into consideration the dimensions and the geometry of the defect and the thickness of the interatrial septum rims. METHODS: Observational, prospective, non-randomized, single-arm study of a cohort of 33 adults with atrial septal defects submitted to percutaneous closure using a self-centered nitinol device (Cera (TM), Lifetech Scientific, Shenzhen, China). The largest and the smallest diameter of the defect, its area and the measurements of the stretched diameter of the sizing balloon were assessed by both echocardiographic modalities. The defects were considered as elliptical or circular according to their geometry; the rims surrounding the defect were considered thick (> 2 mm) or thin. The selected device was equal to or 2 mm larger than the stretched diameter on bi-dimensional transesophageal echocardiography (gold-standard). In an attempt to identify a variable that could replace the stretched balloon diameter, a series of linear correlations were performed. RESULTS: The mean age and weight were 42.1 ± 14.9 years and 66.0 ± 9.4 kgs, respectively; being 22 of the female gender. There were no statistical differences between the largest and smallest diameters of the defects and the stretched diameters determined by both echocardiographic modalities. The correlation between the measurements obtained by both methods was excellent (r > 0.90). The largest defect diameter obtained by three-dimensional transesophageal echocardiography was the variable that showed the best correlation with the selected device size in the entire group (r= 0.89), especially in the subgroups with elliptical geometry (r= 0.96) and with thick rims surrounding the defect (r=0.96). CONCLUSIONS: In this study in adults with ostium secundum atrial septal defects submitted to percutaneous occlusion with the Cera (TM) device, optimal device selection could be performed using solely the largest diameter of the defect obtained by real time three-dimensional transesophageal echocardiography, especially in patients with elliptical defects and thick rims.
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O ecocardiograma como preditor de variáveis hemodinâmicas nas cardiopatias congênitas com hipertensão pulmonar e nos candidatos a transplante cardíaco / Echocardiographyc estimates of hemodynamic parameters in pulmonary hypertension associated with congenital cardiac shunts or cardiomyopathyRibeiro, Zilma Verçosa de Sá 02 March 2009 (has links)
A condição de hipertensão pulmonar é definida como a presença de pressão arterial pulmonar média acima de 25 mmHg em repouso. Esta é a resultante hemodinâmica de vários processos nosológicos que acometem a circulação nos pulmões, notadamente os pequenos vasos pré e intraacinares. A microcirculação pulmonar pode se alterar na presença de enfermidades cardíacas, pulmonares, tromboembólicas, infecto-parasitárias e do tecido conectivo, entre outras. Na ausência dessas condições, o diagnóstico de hipertensão arterial pulmonar idiopática se impõe. Com respeito especificamente à doença cardíaca levando a alterações vasculares pulmonares, temos as situações que acarretam aumento de fluxo sangüíneo pulmonar (cardiopatias congênitas que cursam com defeitos de septação das câmaras ou dos grandes vasos) ou dificuldade de drenagem venosa (disfunção sistólica ou diastólica do ventrículo esquerdo, valvopatia mitral e doenças do átrio esquerdo ou veias pulmonares). As alterações vasculares pulmonares que ocorrem nessas circunstâncias podem dificultar ou impedir o reparo cirúrgico de um defeito congênito de septação cardíaca, ou o encaminhamento de pacientes com doença miocárdica para o transplante. Por essas razões, a avaliação de pacientes com defeitos septais cardíacos ou miocardiopatia deve ser criteriosa. Na maioria das vezes a avaliação não invasiva é suficiente para o planejamento terapêutico. Entretanto, em pacientes com cardiopatia congênita e suspeita clínica de hipertensão pulmonar, assim como naqueles portadores de miocardiopatia candidatos ao transplante, a medida direta da resistência vascular pulmonar, através de procedimento invasivo, se faz necessária. Nas últimas décadas, tem havido interesse progressivo de se ampliar a indicação da avaliação não invasiva, omitindo-se a invasiva, sobretudo com o uso de parâmetros avaliados pela ecocardiografia com Doppler e pela ressonância magnética. O uso dessas medidas, na prática clínica, ainda é restrito, mas tende a ampliar-se. O presente estudo foi idealizado no sentido de se verificar, em portadores de defeitos septais cardíacos ou de miocardiopatia na faixa etária pediátrica, se dados ecocardiográficos poderiam ser preditivos de determinadas condições hemodinâmicas, a ponto de isentar certos pacientes da avaliação invasiva pré-operatória. Esta verificação foi feita nos dois grupos de indivíduos (cardiopatias congênitas ou miocardiopatia), com o exame ecocardiográfico realizado simultaneamente ao cateterismo cardíaco. Foram estudados 30 pacientes com defeitos septais cardíacos (idade entre 0,41 a 58,2 anos) e 23 pacientes com miocardiopatia candidatos a transplante (idade entre 0,40 a 15 anos). Para avaliação comparativa entre o ecocardiograma e o cateterismo foram utilizadas várias medidas. Do ponto de vista ecocardiográfico procurou-se analisar variáveis derivadas do fluxo pulmonar ao Doppler: tempo de aceleração (TAc), tempo de ejeção (TEj), período pré-ejetivo (PPE), integral velocidade-tempo do fluxo sistólico da via de saída do ventrículo direito (VTIVSVD) e índices envolvendo essas variáveis). Além disso, avaliou-se a integral velocidade-tempo do componente sistólico e diastólico da veia pulmonar superior direita (VTIVP) e a razão entre o fluxo pulmonar e o sistêmico (Qp/Qs). Do ponto de vista do cateterismo foram obtidas medidas de pressões, razão entre fluxos pulmonar e sistêmico (Qp/Qs) e razão entre a resistência vascular pulmonar e sistêmica (RVP/RVS). No grupo de indivíduos com cardiopatias congênitas, fundamentalmente foram observadas associações: entre a razão PPE/TEj e a pressão arterial pulmonar diastólica, assim como o índice RVP/RVS; entre a razão PPE/VTIVSVD e RVP/RVS; entre as razões Qp/Qs pelos dois métodos; entre a variável VTIVSVD e a razão das resistências; entre a variável VTIVP e a razão das resistências. No grupo de indivíduos com miocardiopatia foram observadas associações: entre a razão PPE/VTIVSVD e a pressão arterial pulmonar sistólica; entre a razão PPE/TEj e a pressão arterial pulmonar diastólica; entre a variável TAc e a pressão arterial pulmonar média e razão das resistências. Apesar de ter sido possível o desenvolvimento de modelos preditivos para dados hemodinâmicos a partir destas variáveis ecocardiográficas, a dispersão dos valores foi considerável, não permitindo recomendar a adoção dos modelos para a predição pontual na prática clínica. No entanto, os dados mostraram ser possível, a partir da avaliação não invasiva, estimar, com especificidade adequada, valores de Qp/Qs, ao cateterismo, acima de 3,0. Isto foi possível a partir, de valores de Qp/Qs igual ou superiores a 2,89 no exame ecocardiográfico. Alem disso, as variáveis VTIVSVD (igual ou superior a 22 cm) e VTIVP (igual ou superior a 20 cm), para o grupo de pacientes com cardiopatia congênita, mostraram-se capazes de predizer a ocorrência de RVP/RVS 0,1 (cateterismo), com especificidade superior a 0,80. No grupo dos pacientes com miocardiopatia, a variável TAc (igual ou superior a 95 ms) mostrou-se capaz de predizer a ocorrência de RVP/RVS 0,1 (cateterismo) com especificidade também acima de 0,80. Assim sendo, nesses pacientes, o ecocardiograma pôde ser útil na identificação de um subgrupo de indivíduos em situação mais favorável com respeito à hemodinâmica pulmonar, para os quais o cateterismo cardíaco poderia ser considerado desnecessário. Futuros estudos serão importantes para se avaliar os resultados tardios (notadamente pós-operatório) nos pacientes avaliados de forma não invasiva, reforçando, a adequação desse tipo de avaliação. / Pulmonary hypertension is defined as a mean pulmonary arterial pressure of > 25 mmHg registered at rest, during cardiac catheterization. A number of conditions have been demonstrated to cause pulmonary hypertension, including congenital (septal defects) and acquired heart diseases, chronic lung disease, connective-tissue disease, thromboembolic disorders, schistosomosiasis, HIV infection, use of anorexigens, etc. In the absence of all these conditions, a diagnosis of idiopathic pulmonary arterial hypertension is established. In the specific setting of the cardiac disorders, either increased pulmonary blood flow (congenital cardiac septal defects) or altered pulmonary venous drainage ( left ventricular systolic or diastolic dysfunction, mitral valve disease, abnormalities of the left atrium) can cause pulmonary vascular abnormalities leading to pulmonary hypertension. Moderate to severe pulmonary vascular abnormalities lead to increased risk of postoperative complications and/or poor long-term outcomes in patients with septal defects undergoing surgical repair or those with cardiomyopathy undergoing heart transplantation. Thus, for these patients, preoperative measurement of pulmonary vascular resistance by cardiac catheterization is mandatory. In general, those with a pulmonary vascular resistance index of > 6 Wood units·m2 (pulmonary to systemic vascular resistance ratio of > 0,3) are not assigned to operation. In the last decades, there has been growing interest on the development of noninvasive methods/parameters that could allow for decision about the therapeutic strategies without cardiac catheterization. In this way, several parameters derived from Doppler-echocardiographic analysis or magnetic resonance has been used to predict hemodynamic data. In the present study, we used echocardiographic parameters to determine which patients with congenital cardiac septal defects or cardiomyopathy could theoretically be assigned to surgical treatments without catheterization. In order to correlate echocardiographic information with data derived from cardiac catheterization, both procedures were carried out simultaneously. Catheterization was performed as part of the routine evaluation, not specifically for research purposes. Thirty consecutive patients with congenital septal defects (aged 0,41 to 58,2 years) and 23 consecutive patients with cardiomyopathy (aged 0,40 to 15 years) were enrolled Doppler-echocardiographic evaluation consisted of flow analysis at the right and left ventricular outflow tract and pulmonary vein. The following parameters were recorded: right ventricular ejection time (RVET), acceleration time (AcT); right ventricular pre-ejection period (RVPEP); velocity time integral of the right ventricular systolic flow (VTIRVOT); velocity time integral of pulmonary venous flow (VTIPV); indexes involving these variables (AcT/RVET, RVPEP/RVET, RVPEP/VTIRVOT); pulmonary to systemic blood flow ratio (Qp/Qs). The parameters derived from cardiac catheterization included pulmonary and systemic pressures, blood flow and vascular resistance. Blood flow and vascular resistance were expressed as ratios Qp/Qs and PVR/SVR, respectively pulmonary to systemic blood flow and vascular resistance ratios). In patients with congenital septal defects, a Qp/Qs of 2,89 by Doppler-echocardiographic analysis was predictive of Qp/Qs > 3,0 by cardiac catheterization, with specificity > 0.78. For values of 4.0 (echocardiography), the specificity was > 0.91. A VTIRVOT of 22 cm or VTIPV 20 cm could predict PVR/SVR ratios 0.1 with specificity > 0.81. For values of 27 cm and 24 cm respectively, the specificity was > 0.93. In patients with cardiomyopathy, a AcT of 95 msec was predictive of PVR/SVR 0.1 with specificity > 0.85. Doppler-echocardiographic parameters could not predict absolute values of hemodynamic variables with acceptable accuracy. Based on these results we conclude that Doppler-echocardiographic analysis can be used to identify patients with low levels of pulmonary vascular resistance (those with septal defects or cardiomyopathy) and increased pulmonary blood flow (septal defects).These patients could be safely assigned surgical treatments with no need for invasive evaluation. In view of the relatively low levels of sensitivity that we observed (< 0.65), some patients with favourable pulmonary hemodynamics would still be assigned to catheterization in case of adoption of the cut-off levels used in the study. Prediction of absolute values of hemodynamic parameters was not considered sufficiently accurate for decision making. Further studies are obviously necessary to evaluate long-term outcomes in patients treated on the basis of noninvasive evaluation only.
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Valor prognóstico da ecocardiografia sob estresse pela dobutamina e adenosina associada à perfusão miocárdica em tempo real em pacientes com doença arterial coronariana suspeita ou confirmada / Prognostic Value of dobutamine and adenosine stress echocardiography associated with real time myocardial perfusion in patients with known or suspected coronary artery diseaseAlves, Angele Azevedo 26 August 2010 (has links)
A ecocardiografia com perfusão miocárdica em tempo real (EPMTR) permite análise simultânea da contração segmentar miocárdica e análise qualitativa da perfusão miocárdica (PQL), além da quantificação da reserva de fluxo sanguíneo do miocárdio (FSM). A EPMTR quantitativa tem demonstrado melhorar a acurácia na detecção de doença arterial coronariana (DAC), todavia, seu valor prognóstico é desconhecido. Os objetivos deste estudo foram determinar o valor prognóstico das alterações transitórias da CSM e do FSM regional em pacientes com DAC suspeita ou confirmada e identificar dentre os parâmetros analisados qual o melhor preditor de eventos cardíacos. Estudamos 227 pacientes que se submeteram ECMTR sob estresse pela adenosina e 168 pela dobutamina, com sistema de baixo índice mecânico após infusão intravenosa de agente de contraste ecocardiográfico. A reserva de velocidade de repreenchimento () e um índice de fluxo sanguíneo do miocárdio (Anx) foram obtidos a partir da EPMTR quantitativa utilizando-se software Q-Lab. Reserva e reserva do FSM (Ax) foram determinadas como a razão entre os valores obtidos durante o estresse pela adenosina/dobutamina e o repouso. Eventos foram determinados como morte cardíaca, infarto do miocárdio não-fatal, angina instável (eventos maiores) e revascularização do miocárdio percutânea ou cirúrgica (eventos menores). Durante uma média de acompanhamento de 32 meses - adenosina e 34 meses - dobutamina (5 dias - 6,9 anos), 46 eventos ocorreram no grupo adenosina (2 mortes, 6 infartos do miocárdio não-fatais e 11 angina instável) e 38 eventos no grupo dobutamina (3 mortes, 3 infartos do miocárdio não-fatais e 11 angina instável). Pela curva Receiver Operator Characteristics (ROC). os valores de corte da reserva utilizados foram de 2,1 e 2,45 e da reserva de FSM foram de 2,26 e 2,78, para adenosina e dobutamina, respectivamente. A CSM e a PQL foram preditores independentes de eventos totais, pela EPMTR sob estresse pela adenosina (RR,2,8; IC95%; p=0,003 e RR,4,3; IC95%; p<0,001, respectivamente), mas não para eventos maiores. Todavia, foram preditores independentes de eventos totais (RR,3,3; IC95%; p=0,002 e RR,6,7; IC95%; p<0,001, respectivamente) e maiores (RR,3,3; IC95%; p=0,024 e RR,3,7; IC95%; p=0,018, respectivamente) para EPMTR sob estresse pela dobutamina. Os parâmetros quantitativos, reserva e reserva Ax adicionaram valor prognóstico sobre as demais variáveis durante EPMTR pela adenosina para eventos totais (RR,16,5; IC95%, p<0,001 e RR,7,9; IC95%; p<0,001, respectivamente), sendo os únicos preditores de eventos maiores neste grupo (RR,8,7; IC95%; p=0,005 e RR,5,9; IC95%; p=0,023) quando anormais em 2 ou mais territórios coronarianos. Estes parâmetros adicionaram valor prognóstico sobre as demais variáveis durante EPMTR pela dobutamina (RR,23,7; IC95%; p<0,001 e RR,16; IC95%; p<0,001,respectivamente), todavia, somente a reserva , mas não a Ax, foi preditor de eventos maiores neste grupo (RR,21; IC95%; p=0,003) quando anormal em 2 ou mais territórios coronarianos. Concluimos que os parâmetros quantitativos do fluxo sanguíneo miocárdio obtidos pela EPMTR sob estresse pela adenosina e dobutamina fornecem informação prognóstica independente e adicional sobre a análise da CSM e análise qualitativa da perfusão miocárdica em pacientes com suspeita de DAC. Os parâmetros quantitativos, em particular a reserva pode prever pacientes com ainda pior prognóstico (os pacientes com reservas anormais em dois ou mais territórios coronarianos) / Real-time myocardial contrast echocardiography (RTMCE) permits simultaneous analysis of wall motion (WM) and qualitative myocardial perfusion (QMP) beyond quantification of myocardial blood flow reserve (MBFR). Although quantitative RTMCE has been demonstrated to improve the accuracy for detecting coronary artery disease (CAD), its prognostic value is unknown. We sought to determine the prognostic value of transient changes in myocardial WM, QMP and myocardial blood flow during adenosine and dobutamine stress RTMCE in patients with known or suspected CAD and to identify among the parameters, the best predictor of outcome. We studied 227 patients who underwent adenosine stress RTMCE and 168 patients who underwent dobutamine stress RTMCE with low-mechanical index pulse sequence schemes following intravenous infusion of contrast agent. The replenishment velocity reserve () and an index of myocardial blood flow (Anx) were derived from quantitative RTMCE using Q-Lab software. reserve and MBFR reserve was determined as the ratio of values obtained during adenosine/dobutamine and baseline. The study end points were primary outcomes which included: cardiac death, myocardial infarction and unstable angina; and secondary outcomes: which included coronary bypass or angioplasty. During a median follow-up of 32 months - adenosine and 34 months-dobutamine (5 days-6,9years), 46 events occurred adenosine (2 death, 6 nonfatal myocardial infarctions and 11 unstable angina) and 38 events ocurred-dobutamine (3 death, 3 nonfatal myocardial infarctions and 11 unstable angina). By receiver operator characteristics curve, the cut-off value of were 2.1 and 2.45 and of MBRF were 2.26 and 2.78, for adenosine and dobutamine respectively. WM and QMP analysis were independent predictors of total events by adenosine stress RTMCE (RR,2.8,95%,p=0.003 and RR4.3,95%,p<0.001, respectively) but not for primary events. However, were independent predictors of total events (RR,3.3,95%, p=0.002 and RR6.7,95%, p<.001, respectively) and primary events (RR3.3,95%, p=0.024 and RR3.7,95%, p=0.018, respectively) for dobutamine stress RTMCE. Quantitative parameters, both and Ax reserves added even more prognostic value over other variables during adenosine stress RTMCE for total events (RR,16.5,95%, p<0.001 and RR7.9, 95%, p<0.001, respectively), and these parameters were the only predictors of primary events in this group (RR,8.7,95%,p=0.005 and RR5.9,95%, p=0.023) when this parameters were abnormal in two or more coronary territories. These parameters added even more prognostic value over other variables during dobutamine stress RTMCE (RR,23.7,95%, p<0.001 and RR,16,95%,p<0.001, respectively), however, only reserve but not Ax reserve was good and independent predictor of primary events in this group (RR,21,95%,p=0.003) when this parameter was abnormal in two or more coronary territories . In conclusion, the quantitative parameters obtained from adenosine and dobutamine stress Real Time Myocardial Contrast Echocardiography have independent and additional prognostic information over wall motion analysis and qualitative myocardial perfusion in patients with suspected or known coronary artery disease. And, the quantitative analysis of myocardial perfusion, in particular with the B parameter, identifies a subgroup with greater risk for cardiovascular events (those patients with abnormal reserves in two or more coronary territories)
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Imagerie multimodale en cardiologie : application à la surveillance des bioprothèses aortiques / Multimodality imaging in cardiology : application to the assessment of aortic bioprosthesesSalaun, Erwan 20 December 2018 (has links)
L’incidence et la prévalence des maladies valvulaires sont en augmentation, l’épidémiologie de ces maladies se modifie avec une prépondérance des maladies dégénératives, et le traitement considéré est le plus souvent le remplacement valvulaire prothétique, notamment dans le cadre de la sténose aortique qui est la maladie valvulaire la plus fréquente. Les techniques de remplacement valvulaire et les prothèses valvulaires ont grandement évolué ces dernières années, notamment avec le développement des implantations de prothèses par voie percutanée. Cependant les substituts valvulaires aortiques biologiques sont exposés à des complications diverses mettant en jeu la fonction de la prothèse : fuite péri-prothétique, endocardite infectieuse, dégénérescence des tissus biologiques. Ces complications restent des challenges diagnostiques et l’échographie est l’imagerie de référence. Cependant, l’imagerie cardiaque et valvulaire a réalisé de grands progrès, et l’utilisation d’autres techniques ou modalités d’imagerie peut être une alternative ou un complément à l’exploration par échocardiographie : imagerie par scanner, imagerie par résonance magnétique, imagerie nucléaire. Le recours et la combinaison de ces différentes techniques s’intègrent dans une approche globale, nommée imagerie multimodale. L’objectif général de ce projet de doctorat a été d’étudier l’apport de l’imagerie multimodale dans la surveillance des bioprothèses aortiques et l’évaluation des complications et de la dégénérescence structurelle qui peuvent survenir. / The incidence and prevalence of heart valve diseases are increasing worldwide. Their epidemiology also changes, and the required treatment is most often a prosthetic valve replacement, especially for aortic stenosis that is the most frequent heart valve disease. Techniques of valve replacement as well as prosthesis themselves have dramatically evolved in recent years, especially with the development of percutaneous transcatheter procedures. However, biologic aortic valve substitutes are at risk of several complications including prosthetic valve dysfunction, paravalvular regurgitation, infective endocarditis and structural valve deterioration. Correctly diagnose any of these complications still is a challenge but echocardiography plays a pivotal role and remains the gold-standard as per diagnostic imaging. Nonwithsanding the fact that echocardiography is the main imaging modality for valvular anomalies, great progress has been made in cardiac imaging and modalities like CT-Scan, MRI and nuclear imaging are nowadays regularly used along with echocardiography. The use and combination of these different techniques are part of a global approach, entitled multi-modality imaging.The general objective of this doctoral project was to study the contribution of the multi-imaging approach in the assessment of the bioprosthesis function and screening for complications and structural valve deterioration that may occur.
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Transesophageal Echocardiography in Patients Undergoing Elective Coronary Artery Bypass SurgeryPalmgren, Ingrid January 2002 (has links)
<p>Transesophageal echocardiography (TEE) has become a useful tool in monitoring the heart in patients during open-heart surgery. This study was undertaken to evaluate whether it is feasible to use TEE to assess left ventricular myocardial viability in anesthetized patients scheduled for coronary artery bypass grafting (CABG).</p><p>A total of 84 patients were studied. To test myocardial viability, TEE and a low-dose dobutamine stress regimen were used. Echocardiographic data were analyzed off-line using a visual or semiautomatic analysis of segmental left ventricular wall motion (LVWM). Visual assessment was performed by readers blinded to the sequence of events. The agreement between readers in visual analysis of segmental LVWM in the transgastric short-axis view was 73% or higher. Segmental LVWM assessed by TEE was compared to hemodynamic data obtained by thermodilution pulmonary artery catheter (PAC) and coronary angiographic data. Also, using the same low-dose dobutamine stress regimen, TEE findings in the anesthetized patient perioperatively were compared with preoperative transthoracic echocardiography (TTE) findings in the awake patient.</p><p>TEE was found to be feasible and adequate for testing left segmental ventricular viability. A concomitant increase in stroke volume assessed by PAC and decrease in LVWM-score assessed by TEE was found with dobutamine stimulation. Abnormal segmental LVWM corresponded to angiographically stenosed supplying coronary artery vessels. During dobutamine stimulation, 69% of the corresponding segments responded which is a sign of viability. The LVWM response to preoperative TTE and perioperative TEE dobutamine stress was comparable except for a significant difference in the apical segments.</p><p>This study showed that perioperative TEE dobutamine stress could be used to test left ventricular viability and was also a valuable supplement to PAC, angiography and TTE. The acquired knowledge is important and suggest that further development of transesophageal ultrasound technology is warranted.</p>
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Left Ventricular Systolic Dysfunction in 75-year-old Men and Women : A Community-based Study of Prevalence, Screening and Mitral Annulus Motion for Diagnosis and PrognosticsHedberg, Pär January 2005 (has links)
<p>Reduced performance of the left ventricle to eject blood – left ventricular systolic dysfunction (LVSD) – is a common predecessor of the heart failure syndrome. With or without symptoms, LVSD is associated with a poor prognosis. However, with adequate treatment, the development or progression of symptoms, the need for hospitalisation and mortality can all be reduced. In the present work, the occurrence of LVSD was evaluated by echocardiography in a community-based sample of 75-year-old men and women (n = 433). LVSD was a common condition, with a prevalence rate of 6.8%. In nearly half the participants with LVSD, there was no clinical evidence of heart failure.</p><p>Community-based screening for asymptomatic LVSD has been proposed as a strategy to reduce the incidence of heart failure. Because of the high costs and low availability, echocardiography is not a suitable screening tool. The plasma concentration of B-type natriuretic peptide (BNP) has been the most advocated screening tool. Another alternative is the standard 12-lead electrocardiogram (ECG). Both the ECG and BNP were effective in excluding LVSD in our 75-year-old community-based sample. However, compared with BNP, the ECG had considerably better specificity. In screening for LVSD, BNP had a diagnostic value in addition to the ECG, but only in individuals with abnormal ECGs.</p><p>The left ventricular ejection fraction (LVEF) measured by echocardiography is a well-established index for describing left ventricular systolic function. The wall motion index (WMI) and the amplitude of mitral annulus motion (MAM) are suggested as alternative echocardiographic methods. Compared with MAM, the WMI had a more favourable agreement with the LVEF in our 75-year-old participants. Nonetheless, MAM was a strong predictor of mortality. MAM predicted the risk of all-cause and cardiac mortality independently of other risk factors. In addition, when it came to cardiac mortality, the predictive ability of MAM was independent of the LV function measured as the WMI.</p>
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Heart Valve Surgery : Preoperative Assessment and Clinical OutcomeHellgren, Laila January 2005 (has links)
<p>A more global analysis of the outcome of heart valve surgery is desirable to reflect the actual benefit for the patient. This thesis focuses on the preoperative assessment of the patient, and the outcome after surgery with regard to operative mortality, long-term survival, valve-related complications, and quality of life. </p><p>Magnetic resonance imaging and echocardiography were comparable in assessing severe mitral regurgitation, but did not agree in measuring regurgitant fraction. Natriuretic peptides correlated well to regurgitant fraction on magnetic resonance imaging and to PISA and vena contracta on echocardiography. </p><p>The risk of death, myocardial injury and postoperative heart failure after valve surgery has decreased over the last decade whereas the proportion older patients has increased. </p><p>Survival is reduced after mitral valve replacement in patients with severe symptoms whereas patients with less symptoms have excellent survival. Older patients are more often severly symptomatic at the time of mitral valve surgery. </p><p>Event-free survival is superior in patients with a mechanical prosthesis, but not influenced by valve type in older patients. A mechanical prosthesis is associated with a higher risk of bleeding < 5 years from surgery, especially in older patients; and a bioprosthesis is associated with a higher risk of thromboembolism > 5 years from surgery. Ageing with a mechanical prosthesis implied an increased risk for an adverse event, this was not true for bioprostheses. </p><p>Quality of life after complicated heart valve surgery resulted in reduced physical health but equal mental health compared to uncomplicated controls.</p>
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Transesophageal Echocardiography in Patients Undergoing Elective Coronary Artery Bypass SurgeryPalmgren, Ingrid January 2002 (has links)
Transesophageal echocardiography (TEE) has become a useful tool in monitoring the heart in patients during open-heart surgery. This study was undertaken to evaluate whether it is feasible to use TEE to assess left ventricular myocardial viability in anesthetized patients scheduled for coronary artery bypass grafting (CABG). A total of 84 patients were studied. To test myocardial viability, TEE and a low-dose dobutamine stress regimen were used. Echocardiographic data were analyzed off-line using a visual or semiautomatic analysis of segmental left ventricular wall motion (LVWM). Visual assessment was performed by readers blinded to the sequence of events. The agreement between readers in visual analysis of segmental LVWM in the transgastric short-axis view was 73% or higher. Segmental LVWM assessed by TEE was compared to hemodynamic data obtained by thermodilution pulmonary artery catheter (PAC) and coronary angiographic data. Also, using the same low-dose dobutamine stress regimen, TEE findings in the anesthetized patient perioperatively were compared with preoperative transthoracic echocardiography (TTE) findings in the awake patient. TEE was found to be feasible and adequate for testing left segmental ventricular viability. A concomitant increase in stroke volume assessed by PAC and decrease in LVWM-score assessed by TEE was found with dobutamine stimulation. Abnormal segmental LVWM corresponded to angiographically stenosed supplying coronary artery vessels. During dobutamine stimulation, 69% of the corresponding segments responded which is a sign of viability. The LVWM response to preoperative TTE and perioperative TEE dobutamine stress was comparable except for a significant difference in the apical segments. This study showed that perioperative TEE dobutamine stress could be used to test left ventricular viability and was also a valuable supplement to PAC, angiography and TTE. The acquired knowledge is important and suggest that further development of transesophageal ultrasound technology is warranted.
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