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

Insights into left atrial response to pressure and volume overload

Lisi, Matteo January 2016 (has links)
The general purpose of this thesis is to establish the ability of Speckle Tracking Echocardiography (STE) in assessing left atrial (LA) response to pressure and volume overload respectively in aortic stenosis (AS) and mitral regurgitation (MR), and to evaluate its accuracy in predicting LA and right ventricular (RV) fibrosis in patients with end-stage heart failure (HF) undergoing heart transplantation (HTx). I demonstrated that assessment of left ventricular (LV) long axis systolic velocity and amplitude of excursion is more sensitive than simple determination of ejection fraction (EF) for revealing the beneficial impact of MR surgery on overall LV systolic performance. Severe symptomatic AS is associated with LA enlargement and compromised mechanical function with a high incidence of peri-operative atrial fibrillation (AF). Valve replacement reverses these abnormalities and regains normal atrial function, a behaviour which is directly related to the severity of pre-operative LV outflow tract obstruction. Early identification of LA size and function disturbances, as shown by myocardial strain measurements might contribute to better patient’s recruitment for a safe valve replacement. In late stage HF patients, the right ventricle is enlarged, with reduced systolic function due to significant myocardial fibrosis. RV free wall myocardial deformation is the most accurate function measure that correlates with the extent of RV myocardial fibrosis and functional capacity. In patients with preserved EF, severe MR masks LV and LA myocardial dysfunction and correlates with symptoms and post-operative cavity function instability. Three months after MVR, the underlying myocardial disturbances are unmasked suggesting that most pre-operative measurements are subject to loading conditions. Finally LA volume and PALS remain the main predictors of post-operative AF, thus should be used for stratifying surgical risk. STE has been shown to accurately determine the severity of impairment of LA myocardial function shown by suppressed PALS which was the strongest predictor of the presence and extent of fibrosis, over and above other structure and function parameters. These findings may assist in better stratifying patients with end stage HF and identifying particularly those requiring HTx.
82

Mechanical and histological disturbances in advanced heart failure and cardiac transplantation

Cameli, Matteo January 2016 (has links)
The general purpose of this thesis is to establish capability and accuracy of speckle tracking echocardiography (STE) in assessing left atrial (LA), left ventricular (LV) and right ventricular (RV) function and their correlation with myocardial fibrosis, filling pressure and clinical outcomes in advanced heart failure (HF) patients before and after heart transplantation (HT). I demonstrated that HT recipients had impaired LV twist dynamics in the form of reduced rotation twist angle and untwist rate but time to peak twist was not different from the age matched controls and other cardiac surgical patients. With a longitudinal study conducted on patients with refractory HF, the best prognostic power has been shown by RV strain analysis. Among the indexes of LV function, the LV ejection fraction (LVEF) demonstrated the lowest diagnostic accuracy; instead LV global circumferential strain (GCS) showed a better sensitivity and specificity than LV global longitudinal strain (GLS). When analyzing the relationship between different severity of myocardial fibrosis and LV cavity function, the strongest function parameter that correlated with severity of myocardial fibrosis was GLS. In contrast, none of diastolic LV function or even measures of exercise capacity correlated with myocardial fibrosis. In patients with end-stage HF, global peak atrial longitudinal strain (PALS), an index of atrial reservoir function was dependent by pulmonary capillary wedge pressure (PCWP) and LV fibrosis, but not influenced by LV systolic function. Results from this study confirm previous evidence of correlation between impaired global PALS and increased PCWP.
83

Study of NAD(P)H fluorescence in living cardiomyocytes by spectrally resolved time-correlated single photon counting

Ying, Cheng January 2007 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
84

Uso de nanoemulsões lipídicas como veículos de paclitaxel e de metotrexato no tratamento da doença vascular do coração transplantado em coelhos / Does paclitaxel associated to a lipid nanoparticle, methotrexate associated to a lipid nanoparticle or the combination of both improve the cardiac allograft vasculopathy and the inflammatory profile in rabbit heterotopic heart transplantion?

Barbieri, Lucas Regatieri 15 August 2016 (has links)
Introdução: A doença vascular do coração transplantado, consiste em um processo inflamatório proliferativo que compromete o sucesso a longo prazo do transplante cardíaco e não há prevenção ou tratamentos efetivos. Uma nanoemulsão lipídica (LDE) pode carregar agentes quimioterápicos na circulação e concentrá-los nos enxertos cardíacos dos coelhos. O objetivo deste estudo foi investigar os efeitos do paclitaxel combinado a LDE;do metotrexate combinado ao LDE e a associação de ambos quimioterápicos ao LDE nos corações transplantados. Método: 28 coelhos alimentados com dieta com teor de 0,5% de colesterol e submetidos a transplante cardíaco herotópico foram tratados com ciclosporina (dose 10 mg/kg/ dia por via oral) e alocados em 4 grupos de 7 animais.Um grupo recebeu a associação de Metotrexate e LDE endovenosa (4 mg/kg/semana); segundo grupo recebeu por via endovenosa a combinação de Paclitaxel e LDE; o terceiro grupo recebeu a associação de LDE com metotrexate e paclitaxel; grupo controle que recebeu somente solução salina intravenosa. Os animais foram sacrificados 6 semanas após o procedimento. Foram realizadas análises da morfologia,histologia,imunohistoquímica e análise da expressão gênica do enxerto e dos corações nativos. Resultado: Em comparação com o grupo controle,coelhos transplantados e tratados com paclitaxel associado ao LDE apresentaram redução em 50% de estenose em artérias coronárias. Já nos grupos que usaram metotrexate associado a LDE ou paclitaxel combinado com metotrexate e associado a LDE, houve redução em 18% da estenose coronariana em relação ao grupo controle,mas a diferença não apresentou significância estatística.Nos três grupos tratados, houve redução do infiltrado macrofágico. No grupo que recebeu metotrexate associado a LDE,a expressão gênica de fatores pró-inflamatórios( TNF-alfa; MCP1; IL 18; VCAM-1 e MMP-12) foi reduzida drasticamente; enquanto a expressão de agentes anti-inflamatórios(IL 10 por exemplo) aumentou. Nos outros dois grupos (LDE+paclitaxel e LDE+paclitaxel e metotrexate) não houve influência consistente na expressão de genes pró e anti-inflamatórios. Conclusão: A associação paclitaxel e LDE promoveu melhora importante na vasculopatia dos enxertos.A associação metotrexate e LDE e a metotrexate mais palcitaxel e LDE reduziram a estenose de coronárias porém sem significância estatística. O infiltrado macrofagocítico foi reduzido nos três grupos tratados. Tais resultados podem servir de ponte para novos ensaios clínicos / Background: Coronary allograft vasculopathy is an inflammatory-proliferative process that compromises the long-term success of heart transplantation and currently has no effective prevention and treatment. A lipid nanoemulsion (LDE) can carry chemotherapeutic agentsin the circulation and concentrates them in the heart graft in rabbits. The aim of this study was to investigate the effects of paclitaxel (PACLI) binded tire parentesis to LDE, methotrexate (MTX) binded to LDE and the association of both particles in transplanted heart. Methods: Twenty eight rabbits fed 0,5% cholesterol diet and submitted to heterotopic heart transplantation were treated with cyclosporine A (10mg/kg/daily orally) and allocated to four groups of 7 animals. One group was treated with intravenous LDE-MTX (4mg/kg B.W., weekly); a second with LDE-paclitaxel, the third one with association of LDE-PACLI with LDE-MTX and the control group received only weekly intravenous saline solution. Animals were sacrificed 6 weeks later for morphometric, histological, immunohistochemical and gene expression analysis of the graft and native hearts. Results: Compared to controls, grafts of LDE-PACLI treated rabbits showed 50%reduction of coronary stenosis and in the LDE-MTX and LDE-MTX/PACLIstenosiswas around 18% less than control but this difference was not statistically significant. In the 3 treatment groups macrophage infiltration was decreased. In LDE-MTX group, gene expression of pro-inflammatory factors TNF-?, MCP-1, IL-18 and VCAM-1, and MMP-12 was strongly diminished whereas expression of anti-inflammatory IL-10 increased. In the other two treatment, groups (LDE-PACLI and LDE-PACLI/MTX) there was not a consistent influence in pro and anti-inflammatory gene expression. Conclusions: LDE-PACLI promoted strong improvement of the cardiac allograft vasculopathy. LDE- MTX and LDE -MTX/PACLI decreased coronary stenosis but without statistic significance. Macrophage infiltration was decrease in the three treatment groups. This new preparation maybe candidate for future clinical trials
85

Avaliação da massa e força muscular em pacientes no pré e pós-transplante cardíaco / Evaluation of muscle mass and strength in patients in the pre and post heart transplant

Fernandes, Lenise Castelo Branco Camurça 15 September 2015 (has links)
INTRODUÇÃO: Existem poucos estudos demonstrando que anormalidades musculares esqueléticas em pacientes com insuficiência cardíaca crônica persistem meses após o transplante cardíaco. No presente estudo, objetivamos avaliar massa muscular, e força muscular periférica e respiratória em pacientes no pré-transplante cardíaco, e no seguimento precoce (6 meses) e tardio (1,5 e 3 anos) pós-transplante cardíaco. Objetivamos verificar ainda a correlação entre força muscular periférica e respiratória em pacientes no pré e pós-transplante cardíaco. Comparamos, por fim, os dados de pacientes do pré-transplante cardíaco com um grupo controle de indivíduos saudáveis sem doença cardíaca. MÉTODOS: Tratou-se de estudo prospectivo do tipo coorte. Foram selecionados todos os pacientes em lista de espera para transplante cardíaco do Hospital de Messejana, do período de agosto de 2011 a março de 2013. Avaliamos idade, gênero, causas da insuficiência cardíaca, hipertensão, diabetes, tempo de espera na lista, tempo de internamento pós-transplante, tempo de ventilação mecânica, medida da força muscular respiratória, da força muscular periférica, da espessura do adutor do polegar, média bilateral da área de secção transversal do músculo psoas maior, índice de massa corporal e creatinina em todos os pacientes do estudo e no grupo controle. As variáveis de massa e força muscular foram medidas por meio de tomografia computadorizada, paquimetria, manovacuometria e dinamometria. RESULTADOS: Foram encontrados 25 pacientes elegíveis e 23 foram incluídos. Ocorreram 8 óbitos no seguimento precoce, 4 no seguimento tardio e, ao final de 3 anos de seguimento, 11 pacientes sobreviveram com enxerto funcionando. Foram selecionados 23 indivíduos saudáveis para o grupo controle, pareados para gênero, idade, peso e altura. Quando comparamos as variáveis de massa e força muscular dos pacientes do grupo pré-transplante cardíaco com o grupo controle de indivíduos saudáveis foram encontradas diminuição da força muscular periférica (27,0 kg/f vs. 38,2 kg/f), da área de secção transversal do músculo psoas ( 1.238,9 mm2 vs. 1.533,1 mm2) da espessura do músculo adutor do polegar (16,5 mm vs. 23,9 mm), da força muscular inspiratória (60,2 cmH2O vs. 94,8 cmH2O) e da força muscular expiratória (75,2 cmH2O vs. 102,17 cmH2O) nos pacientes do grupo pré-transplante cardíaco. Na comparação entre os períodos pré-transplante cardíaco, seguimento precoce e seguimento tardio pós-transplante cardíaco houve aumento estatisticamente significante (p < 0,001) das seguintes variáveis: força muscular periférica (27,3 kg/f vs. 34,7 kg/f), da área de secção transversal do músculo psoas ( 1.305,4 mm2 vs. 1.431,3 mm2) da espessura do músculo adutor do polegar (15,9 mm vs. 20,2 mm), da força muscular inspiratória (59,5 cmH2O vs. 90,9 cmH2O) e da força muscular expiratória (79,5 cmH2O vs. 101,8 cmH2O) nos 11 pacientes sobreviventes. Ao final do seguimento tardio pós-transplante cardíaco todas as variáveis de massa e força muscular atingiram níveis semelhantes àqueles do grupo controle, exceto a espessura do músculo adutor do polegar. CONCLUSÃO: Os achados demonstraram haver sarcopenia em pacientes no pré-transplante cardíaco, visto que houve diminuição da massa muscular e da força muscular periférica e respiratória confirmando a presença de dois critérios, requisito para fazer o diagnóstico de sarcopenia. O transplante cardíaco proporcionou aumento da força muscular respiratória, da força muscular periférica, da espessura do músculo adutor do polegar e aumento da massa muscular do psoas / INTRODUCTION: There are few studies demonstrating that skeletal muscle abnormalities in patients with chronic heart failure persist for months after heart transplantation. In this study, we aimed to evaluate muscle mass, and peripheral and respiratory muscle strength in patients in pre-heart transplantation, and in the early (6 months) and late (1.5 to 3 years) follow-up after heart transplantation. We also aimed to verify the correlation between peripheral and respiratory muscle strength in patients before and after heart transplantation. Finally, we compared the pre-heart transplantation patients\' data with a control group of healthy individuals without heart disease. METHODS: It was a prospective cohort study. We selected all patients on the waiting list for heart transplantation of Messejana\'s Hospital from August 2011 to March 2013. Age, gender, cause of heart failure, hypertension, diabetes, period on the waiting list, post-transplantation hospitalization time, mechanical ventilation time, measurements of respiratory muscle strength (maximum inspiratory muscle strength and maximum expiratory muscle strength), peripheral muscle strength (hand grip strength), adductor pollicis muscle thickness, the bilateral average of the major psoas muscle cross-sectional area, body mass index and serum creatinine were assessed in all the patients in the study and in control groups. Mass and muscle strength variables were measured using computed tomography, pachymetry, manometry and dynamometry. RESULTS: We found 25 eligible patients and 23 were included. There were 8 deaths in the early follow-up period; by the end of 3-year follow-up there were 11 surviving patients with functioning graft. We selected 23 healthy subjects for the control group, matched for gender, age, weight and height. When we compared the variables mass and muscle strength of the pre heart transplant patients with healthy control subjects were found decreased peripheral muscle strength (hand grip strength) (27.0 kg/f vs. 38.2 kg/f), of the psoas muscle\'s cross-section area (1238.9 mm2 vs. 1533.1 mm2), the adductor pollicis muscle thickness (16.5 mm vs. 23.9 mm), maximum inspiratory muscle strength (60.2 cmH2O vs. 94 8 cmH2O) and maximum expiratory muscle strength (75.2 cm H2O vs. 102.17 cmH2O) in patients in the pre heart transplant group. Comparing the pre-heart transplant periods, the early and late heart transplantation follow-up there was a statistically significant increase (p < 0.001) the following variables: peripheral muscle strength (hand grip strength) (27.3 kg / f vs. 34.7 kg / f ), the psoas muscle\'s cross-sectional area (1305.4 vs. 1431.3 mm 2 mm 2) the adductor pollicis muscle thickness (15.9 mm vs. 20.2 mm), maximum inspiratory muscle strength (59.5 cmH2O vs. 90.9 cm H2O) and maximum expiratory muscle strength (79.5 cm H2O vs. 101.8 cm H2O) in the 11 surviving patients. At the end of post-heart transplant late follow-up all variables mass and muscle strength reached similar levels to those of the control group, except the adductor pollicis muscle thickness. CONCLUSION: The findings showed that there was sarcopenia in patients in pre-heart transplantation period, since there was a decrease in muscle mass and a decrease in muscle strength of peripheral and respiratory muscles confirming the presence of at least two criteria, a requirement to make the diagnosis of sarcopenia. Heart transplantation has provided increased respiratory muscle strength, increased peripheral muscle strength, increased the adductor pollicis muscle thickness and increased psoas muscle mass
86

Efeito da nanoemulsão lipídica associada a paclitaxel na prevenção da doença vascular do coração transplantado. Estudo experimental em coelhos / An artificial nanoemulsion carrying paclitaxel decreases the cardiac allograft vasculopathy. A study in a rabbit graft Model

Contreras, Carlos Alberto Mendez 19 July 2010 (has links)
Introdução: A Doença Vascular do Enxerto (DVE), um processo envolvendo fatores de natureza inflamatória e proliferativa, é a principal causa de morte após o Transplante Cardíaco (TxC), com incidência acima de 50 % ao fim do quinto ano. É possível que a intervenção farmacológica nesses fatores possa resultar na inibição da proliferação de células musculares lisas vasculares e melhora da DVE. Neste sentido, em trabalho anterior desta Instituição, o paclitaxel, agente antiproliferativo usado no tratamento do câncer, foi capaz de regredir as lesões ateromatosas em coelhos com aterosclerose induzida por dieta rica em colesterol. Naquele trabalho, o paclitaxel foi concentrado nas lesões utilizando-se uma nanopartícula lipídica, parecida com a lipoproteína de baixa densidade (LDL), mas sem a parte protéica, denominada LDE. Tendo em vista as dificuldades do tratamento da DVE em pacientes e da grande importância dessa doença para o êxito do procedimento, novas alternativas terapêuticas devem ser procuradas, e o uso do paclitaxel associado à LDE pode ser uma rota interessante, tendo em vista que as bases inflamatórias e proliferativas da DVE são semelhantes às da doença cardiovascular aterosclerótica, onde a LDE-paclitaxel mostrou-se eficiente. Objetivos: Verificar se o tratamento com LDE-Paclitaxel reduz a incidência e o grau de DVE de coelhos submetidos a transplante cardíaco heterotópico. Analisar a biodistribuição da LDE em coelhos submetidos a transplante cardíaco heterotópico. Método: TxC heterotópico em posição cervical foi realizado utilizando-se 21 coelhos da raça New Zealand vermelhos como doadores e 21 coelhos brancos como receptores (peso ± 3 kg). Os coelhos receptores receberam dieta com acréscimo de 0,5 % de colesterol e ciclosporina A na dose de 10 mg/kg/dia via oral como imunossupressor. Foram divididos em 2 grupos: um grupo, constituído de 11 animais, foi tratado com LDE-Paclitaxel na dose de 4 mg/kg/semana, durante 6 semanas, por via endovenosa. O outro grupo (controle) compôs-se de 10 animais tratados com 3 mL de solução fisiológica por via endovenosa, semanalmente, durante 6 semanas. A biodistribuição da LDE foi determinada em 4 animais do grupo controle, injetando-se a LDE marcada com éter de colesterol radioativo 24 h antes do sacrifício, seguindose a contagem de radioatividade nos corações e outros tecidos após extração lipídica. Após o sacrifício dos animais, retiraram-se os corações nativo e transplantado para análise histológica com coloração H/E e Verhoeff-van Gieson. A área transversal das artérias coronárias foi estimada pela medida da lamina elástica interna e da área do lúmen. A porcentagem de estenose foi calculada da diferença entre área do lúmen do vaso e a área da lamina elástica interna. Análise estatística com ANOVA e o teste T, com valor p <= 0,05 considerado significante. Resultados: A captação da LDE pelo coração transplantado foi quase 4 vezes maior do que no coração nativo (p<=0,0001). Nos animais tratados com LDE-paclitaxel, houve uma dramática melhora no status das artérias coronárias dos corações transplantados, ocorrendo um acentuado aumento de 3 vezes na área da luz dos vasos (p<=0,031) e de redução da estenose em 45% (p<=0,0008). Conclusões: A LDE é capaz de concentrar-se no coração transplantado, o que possibilita o direcionamento do paclitaxel para o enxerto. O tratamento com LDE-paclitaxel reduziu acentuadamente a DVE, o que pode abrir uma nova perspectiva para o controle da doença vascular do enxerto. / Introduction: Cardiac Allograft Vasculopathy (CAV), a process involving factors of inflammatory and proliferative nature, is the leading cause of death after heart transplantation (HT), with incidence above 50% after the fifth year. It is possible that pharmacological intervention on these factors may result in inhibiting the proliferation of vascular smooth muscle cells and improves the CAV. Thus, in previous studies of this institution, paclitaxel, an antiproliferative agent used in cancer treatment, was able to recede the atheromatous lesions in rabbits with atherosclerosis induced by high cholesterol diet. In that study, paclitaxel was concentrated in the lesions using a lipid nanoparticle, similar to low density lipoprotein (LDL) but without the protein part, called LDE. Given the difficulties of the treatment of CAV in HT patients and the great importance of this disease to the success of the procedure, new therapeutic alternatives must be sought, and the use of paclitaxel associated to LDE can be an interesting route, given that the bases inflammatory and proliferation of CAV are similar to those of atherosclerotic cardiovascular disease, where the LDE-paclitaxel was efficient. Objectives: To determine whether treatment with LDE-paclitaxel reduces the incidence and degree of CAV in rabbits undergoing heterotopic heart transplantation. To analyze the biodistribution of LDE in rabbits undergoing heterotopic heart transplantation. Methods: Heterotopic HT in cervical position was performed using 21 New Zealand red rabbits as donors and 21 white rabbits as recipients (weight ± 3 kg). The receptors rabbits were fed regular chow with added 0.5% cholesterol and with cyclosporine A, 10 mg / kg / day orally as immunosuppressants. They were divided into two groups: one consisting of 11 animals was treated with LDE-paclitaxel at a dose of 4 mg / kg / week for 6 weeks intravenously. The other group (control) was composed of 10 animals treated with 3 ml of saline intravenously weekly for six weeks. The biodistribution of LDE was determined in four control animals, by injecting the LDE labeled with radioactive cholesteryl ether 24 h before sacrifice, followed by radioactivity count in the hearts and other tissues after lipid extraction. After sacrificing the animals, we excised the native and transplanted hearts for histological staining with H / E and Verhoeff-van Gieson. The cross-sectional area of the coronary arteries was estimated by measuring the internal elastic lamina and the lumen area. The percentage of stenosis was calculated from the difference between the area of the vessel lumen and the area of internal elastic lamina. Statistical analysis with ANOVA and T test with p value <= 0.05 was considered significant. Results: The uptake of LDE for the transplanted heart was almost fourfold higher than in the native heart (p<=0.0001). In animals treated with LDE-paclitaxel, there was a dramatic improvement in the status of the coronary arteries of the transplanted hearts, indicating by a marked increase of three times of the vascular lumen area (p<=0.031) and reduction of stenosis in 45% (p<=0.0008). Conclusions: The LDE is able to concentrate on the transplanted heart, which enables the targeting of paclitaxel to the graft. Treatment with LDE-paclitaxel markedly reduced CAV in the transplanted heart, which may open a new perspective for control of Cardiac Allograft Vasculopathy.
87

Intravaskuläre Ultraschalluntersuchung bei Diagnostik und interventioneller Therapie von Herzkranzgefäßerkrankungen am Beispiel der Transplantatvaskulopathie

Bocksch, Wolfgang 23 April 2002 (has links)
Es wurde die Bedeutung der intravaskulären Ultraschalluntersuchung (IVUS) bei Diagnostik (1) und interventioneller Therapie (2) der koronaren Herzerkrankung am Beispiel der Transplantatvaskulopathie (TVP) untersucht. 1. Bei 321 Patienten post-HTx-Patienten ohne relevante Stenosen im Koronarangiogramm wurde eine dreidimensionale Rekonstruktion des Ramus interventricularis anterior (LAD) und des linkskoronaren Hauptstammes aus den mittles manueller Katheterrückzugstechnik aquirierten IVUS-Bildern durchgeführt und die intrakoronare Plaqueverteilung und die mittlere Plaquelast der einzelnen Koronarsegmente analysiert. Bei 296 Patienten (92%) fanden angiographisch nicht sichtbare frühe Plaquebildung. 48% dieser Patienten zeigten ein fokal,polyfokale, 52% ein diffuses Plaqueverteilungsmuster. Unabhängige Prädiktoren für das Auftreten einer diffusen TVP waren männliches Geschlecht des Empfängers, das Zeitintervall zwischen HTx und IVUS-Untersuchung (Transplantationszeit) und das Spenderalter. In beiden morphologischen Untergruppen war ein häufigere und stärkere Plaquebildung in den proximalen Koronarsegmenten nachweisbar. Ein distaler Gefäßbefall war bei diffuser Plaquebildung signifikant häufiger und zeigte eine steigende Inzidenz mit zunehmender Transplantationszeit. Somit stellt das longitudinale Plaqueverteilungsmuster und der distale Gefäßbefall einen zusätzlichen morphologischen Marker für den Schweregrad einer beginnenden Transplantatvaskulopathie dar. 2. Bei 36 post-HTx Patienten wurden 62 Stenosen prospektiv mit einer IVUS-gesteuerten, gefäßgrößen-adaptierten Stentimplantation erfolgreich versorgt. Die Stentgröße wurde dem Mittelwert aus Lumen- und Gefäßdurchmessers im proximalen Referenzsegment angepaßt. Nach Vordilatation fand sich ein Lumengewinn von 1.26± 0.16 auf 1.95 ± 0.27mm, nach abschließender Stentimplantation auf 2.94 ± 0.37mm. Nach 6 Monaten betrug die binäre In-Stent-Restenosierungsrate 21.8%, eine Re-PTCA wurde bei 10.9 % durchgeführt. / The role of intravascular ultrasound imaging in diagnosis of coronary disease (1) and guiding percutaneous coronary intervention (2) was evaluated in patients with transplant vasculopathy. 1. In 321 post-HTx-patients without angiographic evidence of coronary disease, three-dimensional intravascular ultrasound imaging of the left anterior descending coronary artery (LAD) and the left main coronary artery was performed. Intracoronary plaque distribution and plaque burden was evaluated for each coronary segment. In 296 patients (92%) angiographically silent plaque was detected by IVUS. 48% of these patients showed a focal,polyfocal and 52% a diffuse plaque distribution pattern. Independent predictors of diffuse plaque formation were male gender of the recipient, transplantation time and donor age. In both morphological subgroups of plaque distribution the incidence and magnitude of plaque formation was highest in the proximal LAD segment. Plaque formation in the distal LAD was more frequent in diffuse plaque formation and increased significantly with time after transplantation. Therefore longitudinal plaque distribution pattern and distal vessel involvment are useful additional morphological markers for staging of beginning transplant vasculopathy. 2. In 36 post-HTx-patients 62 coronary stenosis were successfully treated by vessel-size adapted stenting by use of intravascular ultrasound guidance. The stent size was adapted to the proximal reference segment´s mean of lumen/vessel diameter. After pre-dilatataion the minimal lumen diameter increased from 1.26± 0.16 to 1.95 ± 0.27mm and to 2.94 ± 0.37mm after final stent implantation. After 6 months, binary in-stent-restenosis rate was 21.8% and target vessel revascularization rate 10.9%, respectively.
88

Histomorphometrische Untersuchungen myokardialer Blutgefäßveränderungen nach Herztransplantation.

Hiemann, Nicola 14 December 1998 (has links)
Anhand von immunhistochemischen Färbemethoden wurde die Expression von CD 31 (immunhistochemischer Marker für Endothelzellen) und -Aktin (immunhistochemischer Marker für glatte Muskelzellen) auf Zellen der intramyokardialen Blutgefäße herztransplantierter Patienten histomorphometrisch ausgewertet. In die Bewertung der myokardialen Strukturen ging auch die Untersuchung der jeweiligen zugehörigen HE-Färbungen mit ein. Ziel dieser Untersuchungen war die Beurteilung von qualitativen und quantitativen Unterschieden dieser Marker während eines Untersuchungszeitraumes von 14 Monaten nach Herztransplantation (HTx) bei Patienten mit einer angiographisch diagnostizierten Transplantatvaskulopathie (TVP) mit Patienten ohne einer prä- bzw. postmortem diagnostizierten TVP. Der Einsatz dieser Immunomarker richtete sich hierbei auf die selektive Darstellung der terminalen Strombahn mit der Fragestellung, ob ein intramyokardiales morphologisches Korrelat zu der TVP der epikardialen Blutgefäße existiert und ob die histomorphometrische Auswertung der bewerteten Strukturen eine mögliche Frühdiagnose der TVP nach HTx zuläßt. Des weiteren sollte eine mögliche Assoziation der TVP mit den demographischen Charakteristika sowie der Anzahl und dem Schweregrad der Rejektionsepisoden der untersuchten Patienten überprüft werden. Als Basis dienten dabei in Paraffin eingebettete rechtsventrikuläre Rejektionskontrollbiopsien, die im Rahmen der routinemäßig durchgeführten Abstoßungsdiagnostik entnommenen wurden. Nach morphologischer Bewertung dieser Schnitte im Hinblick auf die Existenz und den Schweregrad einer Abstoßungsreaktion wurden diese immunhistochemisch aufbereitet und anschließend quantitativausgewertet. Im Rahmen dieser Arbeit weist die quantitativ- histomorphometrische Erfassung intramyokardialer Blutgefäße in rechtsventrikulären Rejektionskontrollbiopsien auf die mögliche Frühdiagnose einer TVP nach HTx hin. Dieses Verfahren könnte die zur Zeit verwendeten diagnostischen Methoden ergänzen. Jedoch sind noch weitere prospektive klinische Studien für die Validierung dieser Ergebnisse notwendig. / In this study, immunohistochemical and histomorphometric investigations were performed in order to investigate the expression of CD 31 (immunohistochemical marker for endothelial cells) and -Aktin (immunohistochemical marker for smooth muscle cells) on cells of intramyocardial blood vessels in heart transplant (HTx) patients. The evaluation of myocardial structures also implicated the investigation of the corresponding histological H & E stainings. The aim of this study was to ascertain whether HTx patients with angiographic evidence of graft vessel disease (GVD) showed different qualitative and quantitative expression of the above mentioned immunomarkers than HTx patients with no angiopraphic or postmortem signs of this phenomenon. The investigation time included the first 14 months after HTx. The use of these immunomarkers made possible the selective representation of the terminal vascular system to answer the question, as to whether there existed an intramyocardial morphological correlate to GVD of epicardial coronary arteries and whether histomorphometric evaluation of small vessels permits early diagnosis of GVD after HTx. In addition, demographic data, as well the number and grade of rejection episodes of the studied patients, were reviewed in order to ascertain whether there might be an association of these characteristics with GVD. The material studied consisted of paraffin-embedded right ventricular rejection control samples from routine postoperative diagnostic management, which were used to reveal acute rejection episodes. After morphological evaluation of histological slices with regard to the appearence and severity of acute rejection, immunohistochemical staining was performed and finally a quantitative investigation was done. According to the results of this study, quantitative histomorphometric investigations of intramyocardial blood vessels in right ventricular rejection control samples permit the early diagnosis of GVD after HTx and completes the present diagnostic tools. But further prospective clinical studies are necessary to confirm these results.
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Efeito agudo do exercício físico em piscina aquecida versus em solo sobre a pressão arterial e variabilidade da frequência cardíaca em indivíduos transplantados cardíacos / Acute effects of water-based exercise versus land-based exercise on ambulatory blood pressure and heart rate variability in heart transplant recipients

Castro, Rafael Ertner 05 October 2015 (has links)
O transplante cardíaco (TX) é um reconhecido procedimento de escolha para a insuficiência cardíaca refratária, resultando em melhora na sintomatologia e na qualidade de vida dos pacientes. Todavia, estes pacientes apresentam capacidade física reduzida e alta prevalência de comorbidades. A terapia imunossupressora, bem como a denervação cardíaca pós-cirurgia tornam a hipertensão arterial sistêmica (HAS) a mais prevalente das comorbidades. Avaliamos o efeito agudo do exercício aeróbio em piscina aquecida e em solo sobre a dinâmica do comportamento tensional na pressão arterial durante 24 horas (MAPA-24h) e na atividade autonômica do coração. Dezoito pacientes (6 mulheres) clinicamente estáveis (5 ± 0,7 anos de cirurgia), 45,7 ± 2,7 anos de idade, foram submetidos a 30 minutos de exercício aeróbio em piscina, exercício aeróbio em esteira rolante (solo) ou 30 minutos em repouso (controle) em ordem randômica (2 a 5 dias entre cada sessão). A intensidade do exercício foi entre 11 e 13 em uma escala subjetiva de esforço que vai de 6 a 20. Foram avaliadas a variabilidade da frequência cardíaca (VFC) no início, logo após o exercício e na fase de recuperação, bem como a MAPA-24h após cada sessão. Após o exercício em piscina, foram observadas reduções significativas em relação à sessão controle nas médias horárias da pressão arterial sistólica (PAS) nas três primeiras horas (15h = 12,2 ± 3,1 mmHg, p = 0,004; 16h = 11,1 ± 2,8 mmHg, p = 0,003; 17h = 12,3 ± 3,1 mmHg, p =0,003) e após a sétima hora (21h = 7,8 ± 1,7 mmHg, p = 0,001) de análise, e nas médias diária (4 ± 1,6 mmHg, p = 0,02) e horária da pressão arterial diastólica (PAD) na primeira (15h = 7,7 ± 2,8 mmHg, p = 0,04) e sétima hora (21h = 6,6 ± 1,5 mmHg, p = 0,002). Após o exercício em solo foram vistas reduções significativas em relação à sessão controle nas médias horárias da PAS durante a segunda (16h = 5,3 ± 1,6 mmHg, p = 0,01), terceira (17h = 7,3 ± 2,3 mmHg, p = 0,02) e vigésima primeira hora (11h = 7,8 ± 1,7 mmHg, p = 0,02) e nas médias horárias da PAD durante a segunda (16h = 5,0 ± 1,7 mmHg, p = 0,04), a vigésima primeira (11h = 8,3 ± 2,5 mmHg, p = 0,01) e vigésima quarta hora (14h = 6,9 ± 2,4 mmHg, p = 0,03) de análise. A VFC apresentou não diferença significativa em nenhuma das intervenções de exercício. Assim sendo, ambas as sessões de exercício promoveram reduções similares da pressão arterial ambulatorial dos pacientes pós-TX, sugerindo que elas podem ser uma importante ferramenta para o combate da HAS nessa população de alto risco / Heart transplantation (TX) is a recognized procedure of choice for refractory heart failure, resulting in improvement in symptoms and quality of life of patients. However, these patients have reduced physical capacity and high prevalence of comorbidities. Immunosuppressive therapy and post-surgery cardiac denervation make systemic hypertension (SH) the most prevalent comorbiditie. We evaluated the acute effect of aerobic heated water-based exercise and land-based exercise on the dynamic tension behavior in blood pressure for 24 hours (24-h ABP) and autonomic activity of the heart. Eighteen patients (6 females) clinically stable (5 ± 0.7 years of surgery), 45.7 ± 2.7 years old, underwent 30 minutes of aerobic exercise in the swimming pool, aerobic exercise on a treadmill (land) or non-exercise control (control) in random order (2-5 days between each session). Exercise intensity was set at 11-13 in the 6-20 rating of perceived exertion scale. We evaluated the heart rate variability (HRV) at the beginning, right after exercise and during the recovery phase, and the 24-h ABP after each session. After water-based exercise, significant reductions were observed in relation to the control session on hourly average systolic blood pressure (SBP) in the first three hours (15h = 12.2 ± 3.1 mmHg, p = 0.004; 16h = 11.1 ± 2.8 mmHg, p = 0.003; 17h = 12.3 ± 3.1 mmHg, p = 0.003) and after the seventh time (21h = 7.8 ± 1.7 mmHg, p = 0.001) analysis, and the daily averages (4 ± 1.6 mmHg, p = 0.02) and hourly average diastolic blood pressure (DBP) in the first (15h = 7.7 ± 2.8 mmHg, p = 0.04) and seventh hours ( 21h = 6.6 ± 1.5 mmHg, p = 0.002). After land-based exercise significant reductions were observed when compared to control session in the hourly averages of SBP during the second (16h = 5.3 ± 1.6 mmHg, p = 0.01), third (17h = 7.3 ± 2 , 3 mm Hg, p = 0.02) and twenty-first time (= 11h 7.8 ± 1.7 mmHg, p = 0.02) and in hourly averages DBP during the second (= 16h 5.0 ± 1 7 mm Hg, p = 0.04), the twenty-first (11h = 8.3 ± 2.5 mmHg, p = 0.01) and twenty fourth hour (14h = 6.9 ± 2.4 mmHg, p = 0 03) analysis. HRV showed no significant difference in any of exercise interventions. Therefore, both exercise sessions promoted similar reductions in ambulatory blood pressure of post-TX patients, suggesting that they can be an important tool to counteract hypertension in this high-risk population
90

Câncer de mama em mulheres muito jovens: estudo clinicopatológico de 149 pacientes &#8804;25 anos de idade / Acute effects of water-based exercise versus land-based exercise on ambulatory blood pressure and heart rate variability in heart transplant recipients

Moura, Rafael de Deus 02 October 2015 (has links)
O transplante cardíaco (TX) é um reconhecido procedimento de escolha para a insuficiência cardíaca refratária, resultando em melhora na sintomatologia e na qualidade de vida dos pacientes. Todavia, estes pacientes apresentam capacidade física reduzida e alta prevalência de comorbidades. A terapia imunossupressora, bem como a denervação cardíaca pós-cirurgia tornam a hipertensão arterial sistêmica (HAS) a mais prevalente das comorbidades. Avaliamos o efeito agudo do exercício aeróbio em piscina aquecida e em solo sobre a dinâmica do comportamento tensional na pressão arterial durante 24 horas (MAPA-24h) e na atividade autonômica do coração. Dezoito pacientes (6 mulheres) clinicamente estáveis (5 ± 0,7 anos de cirurgia), 45,7 ± 2,7 anos de idade, foram submetidos a 30 minutos de exercício aeróbio em piscina, exercício aeróbio em esteira rolante (solo) ou 30 minutos em repouso (controle) em ordem randômica (2 a 5 dias entre cada sessão). A intensidade do exercício foi entre 11 e 13 em uma escala subjetiva de esforço que vai de 6 a 20. Foram avaliadas a variabilidade da frequência cardíaca (VFC) no início, logo após o exercício e na fase de recuperação, bem como a MAPA-24h após cada sessão. Após o exercício em piscina, foram observadas reduções significativas em relação à sessão controle nas médias horárias da pressão arterial sistólica (PAS) nas três primeiras horas (15h = 12,2 ± 3,1 mmHg, p = 0,004; 16h = 11,1 ± 2,8 mmHg, p = 0,003; 17h = 12,3 ± 3,1 mmHg, p =0,003) e após a sétima hora (21h = 7,8 ± 1,7 mmHg, p = 0,001) de análise, e nas médias diária (4 ± 1,6 mmHg, p = 0,02) e horária da pressão arterial diastólica (PAD) na primeira (15h = 7,7 ± 2,8 mmHg, p = 0,04) e sétima hora (21h = 6,6±1,5 mmHg, p = 0,002). Após o exercício em solo foram vistas reduções significativas em relação à sessão controle nas médias horárias da PAS durante a segunda (16h = 5,3±1,6 mmHg, p = 0,01), terceira (17h = 7,3 ± 2,3 mmHg, p = 0,02) e vigésima primeira hora (11h = 7,8 ± 1,7 mmHg, p = 0,02) e nas médias horárias da PAD durante a segunda (16h = 5,0 ± 1,7 mmHg, p = 0,04), a vigésima primeira (11h = 8,3 ± 2,5 mmHg, p = 0,01) e vigésima quarta hora (14h = 6,9 ± 2,4 mmHg, p = 0,03) de análise. A VFC apresentou não diferença significativa em nenhuma das intervenções de exercício. Assim sendo, ambas as sessões de exercício promoveram reduções similares da pressão arterial ambulatorial dos pacientes pós-TX, sugerindo que elas podem ser uma importante ferramenta para o combate da HAS nessa população de alto risco / Heart transplantation (TX) is a recognized procedure of choice for refractory heart failure, resulting in improvement in symptoms and quality of life of patients. However, these patients have reduced physical capacity and high prevalence of comorbidities. Immunosuppressive therapy and post-surgery cardiac denervation make systemic hypertension (SH) the most prevalent comorbiditie. We evaluated the acute effect of aerobic heated water-based exercise and land-based exercise on the dynamic tension behavior in blood pressure for 24 hours (24-h ABP) and autonomic activity of the heart. Eighteen patients (6 females) clinically stable (5 ± 0.7 years of surgery), 45.7 ± 2.7 years old, underwent 30 minutes of aerobic exercise in the swimming pool, aerobic exercise on a treadmill (land) or non-exercise control (control) in random order (2-5 days between each session). Exercise intensity was set at 11-13 in the 6-20 rating of perceived exertion scale. We evaluated the heart rate variability (HRV) at the beginning, right after exercise and during the recovery phase, and the 24-h ABP after each session. After water-based exercise, significant reductions were observed in relation to the control session on hourly average systolic blood pressure (SBP) in the first three hours (15h = 12.2 ± 3.1 mmHg, p = 0.004; 16h = 11.1 ± 2.8 mmHg, p = 0.003; 17h = 12.3 ± 3.1 mmHg, p = 0.003) and after the seventh time (21h = 7.8 ± 1.7 mmHg, p = 0.001) analysis, and the daily averages (4 ± 1.6 mmHg, p = 0.02) and hourly average diastolic blood pressure (DBP) in the first (15h = 7.7 ± 2.8 mmHg, p = 0.04) and seventh hours ( 21h = 6.6 ± 1.5 mmHg, p = 0.002). After land-based exercise significant reductions were observed when compared to control session in the hourly averages of SBP during the second (16h = 5.3 ± 1.6 mmHg, p = 0.01), third (17h = 7.3 ± 2 , 3 mm Hg, p = 0.02) and twenty-first time (= 11h 7.8 ± 1.7 mmHg, p = 0.02) and in hourly averages DBP during the second (= 16h 5.0 ± 1 7 mm Hg, p = 0.04), the twenty-first (11h = 8.3 ± 2.5 mmHg, p = 0.01) and twenty fourth hour (14h = 6.9 ± 2.4 mmHg, p = 0 03) analysis. HRV showed no significant difference in any of exercise interventions. Therefore, both exercise sessions promoted similar reductions in ambulatory blood pressure of post-TX patients, suggesting that they can be an important tool to counteract hypertension in this high-risk population

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