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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.
171

Modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna / Stable experimental model of carotid artery saccular aneurysm in swine using the internal jugular vein

Silva Junior, Severino Lourenço da January 2012 (has links)
Objetivo: Desenvolver um modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna. Materiais e Métodos: Em 12 suínos sadios, com peso variando entre 25 e 50kg, sendo 5 machos e 7 fêmeas, foi confeccionado aneurisma na artéria carótida comum direita. Após arteriotomia elípitica foi realizada anastomose término-lateral com coto distal de veia jugular interna. O volume do aneurisma era calculado de maneira que o valor não excedia em 27 vezes o valor da área da arteriotomia. Após 6 dias era realizada angiografia e a análise microscópica dos aneurismas para avaliar perviedade, trombose parcial ou total dos mesmos. Resultados: Houve ganho de peso significante dos suínos no intervalo de tempo entre a confecção do aneurisma e a angiografia (p=0,04). Foi observada perviedade aneurismática em 10 suínos (83%). Ocorreu infecção de ferida operatória em 2 animais (16,6%) ambas com início de aparecimento 3 dias após a confecção do aneurisma. Após análise histológica dos aneurismas, foram detectados trombos ocluindo parcialmente a luz aneurismática em 9 suínos (75%). Nesses animais observou-se que em média 9% da luz aneurismática estava preenchida por trombos. Conclusão: O modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna foi desenvolvido. / Purpose: To develop an stable experimental model of carotid artey saccular aneurysm in swine using the internal jugular vein. Methods: In 12 healthy swines, weighing between 25 and 50kg, 5 males and 7 females, aneurysms were made aneurysm in the right common carotid artery. After elliptical arteriotomy it was made end-to-side anastomosis with the distal stump of the internal jugular vein. The volume of aneurysms was calculated in a way that the value did not exceed on 27 times the value of the area of arteriotomy. After six days was performed angiography and microscopic analysis of aneurysms to assess patency, partial or total thrombosis of them. Results: There was a significant weight gain of swines in the time interval between the making of the aneurysm and angiography (p = 0.04). Aneurysmal patency was observed in 10 swines (83%). Wound infection occurred in 2 animals (16.6%) both with early onset 3 days after making of the aneurysm. After histological analysis of aneurysms, thrombus were founded partially occluding the light aneurysm in 9 animals (75%). In these animals it was observed that in average 9% of the aneurysmal lumen was filled with thrombus. Conclusion: The stable experimental model of carotid artey saccular aneurysm in swine using the internal jugular vein was developed.
172

The Influence of Dome Size, Parent Vessel Angle, and Coil Packing Density On Coil Embolization Treatment in Cerebral Aneurysms

January 2013 (has links)
abstract: A cerebral aneurysm is a bulging of a blood vessel in the brain. Aneurysmal rupture affects 25,000 people each year and is associated with a 45% mortality rate. Therefore, it is critically important to treat cerebral aneurysms effectively before they rupture. Endovascular coiling is the most effective treatment for cerebral aneurysms. During coiling process, series of metallic coils are deployed into the aneurysmal sack with the intent of reaching a sufficient packing density (PD). Coils packing can facilitate thrombus formation and help seal off the aneurysm from circulation over time. While coiling is effective, high rates of treatment failure have been associated with basilar tip aneurysms (BTAs). Treatment failure may be related to geometrical features of the aneurysm. The purpose of this study was to investigate the influence of dome size, parent vessel (PV) angle, and PD on post-treatment aneurysmal hemodynamics using both computational fluid dynamics (CFD) and particle image velocimetry (PIV). Flows in four idealized BTA models with a combination of dome sizes and two different PV angles were simulated using CFD and then validated against PIV data. Percent reductions in post-treatment aneurysmal velocity and cross-neck (CN) flow as well as percent coverage of low wall shear stress (WSS) area were analyzed. In all models, aneurysmal velocity and CN flow decreased after coiling, while low WSS area increased. However, with increasing PD, further reductions were observed in aneurysmal velocity and CN flow, but minimal changes were observed in low WSS area. Overall, coil PD had the greatest impact while dome size has greater impact than PV angle on aneurysmal hemodynamics. These findings lead to a conclusion that combinations of treatment goals and geometric factor may play key roles in coil embolization treatment outcomes, and support that different treatment timing may be a critical factor in treatment optimization. / Dissertation/Thesis / M.S. Bioengineering 2013
173

The Effects of Endovascular Treatment Parameters on Cerebral Aneurysm Hemodynamics

January 2013 (has links)
abstract: A cerebral aneurysm is an abnormal ballooning of the blood vessel wall in the brain that occurs in approximately 6% of the general population. When a cerebral aneurysm ruptures, the subsequent damage is lethal damage in nearly 50% of cases. Over the past decade, endovascular treatment has emerged as an effective treatment option for cerebral aneurysms that is far less invasive than conventional surgical options. Nonetheless, the rate of successful treatment is as low as 50% for certain types of aneurysms. Treatment success has been correlated with favorable post-treatment hemodynamics. However, current understanding of the effects of endovascular treatment parameters on post-treatment hemodynamics is limited. This limitation is due in part to current challenges in in vivo flow measurement techniques. Improved understanding of post-treatment hemodynamics can lead to more effective treatments. However, the effects of treatment on hemodynamics may be patient-specific and thus, accurate tools that can predict hemodynamics on a case by case basis are also required for improving outcomes.Accordingly, the main objectives of this work were 1) to develop computational tools for predicting post-treatment hemodynamics and 2) to build a foundation of understanding on the effects of controllable treatment parameters on cerebral aneurysm hemodynamics. Experimental flow measurement techniques, using particle image velocimetry, were first developed for acquiring flow data in cerebral aneurysm models treated with an endovascular device. The experimental data were then used to guide the development of novel computational tools, which consider the physical properties, design specifications, and deployment mechanics of endovascular devices to simulate post-treatment hemodynamics. The effects of different endovascular treatment parameters on cerebral aneurysm hemodynamics were then characterized under controlled conditions. Lastly, application of the computational tools for interventional planning was demonstrated through the evaluation of two patient cases. / Dissertation/Thesis / Ph.D. Bioengineering 2013
174

Modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna / Stable experimental model of carotid artery saccular aneurysm in swine using the internal jugular vein

Silva Junior, Severino Lourenço da January 2012 (has links)
Objetivo: Desenvolver um modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna. Materiais e Métodos: Em 12 suínos sadios, com peso variando entre 25 e 50kg, sendo 5 machos e 7 fêmeas, foi confeccionado aneurisma na artéria carótida comum direita. Após arteriotomia elípitica foi realizada anastomose término-lateral com coto distal de veia jugular interna. O volume do aneurisma era calculado de maneira que o valor não excedia em 27 vezes o valor da área da arteriotomia. Após 6 dias era realizada angiografia e a análise microscópica dos aneurismas para avaliar perviedade, trombose parcial ou total dos mesmos. Resultados: Houve ganho de peso significante dos suínos no intervalo de tempo entre a confecção do aneurisma e a angiografia (p=0,04). Foi observada perviedade aneurismática em 10 suínos (83%). Ocorreu infecção de ferida operatória em 2 animais (16,6%) ambas com início de aparecimento 3 dias após a confecção do aneurisma. Após análise histológica dos aneurismas, foram detectados trombos ocluindo parcialmente a luz aneurismática em 9 suínos (75%). Nesses animais observou-se que em média 9% da luz aneurismática estava preenchida por trombos. Conclusão: O modelo experimental estável de aneurisma sacular em carótida de suínos utilizando veia jugular interna foi desenvolvido. / Purpose: To develop an stable experimental model of carotid artey saccular aneurysm in swine using the internal jugular vein. Methods: In 12 healthy swines, weighing between 25 and 50kg, 5 males and 7 females, aneurysms were made aneurysm in the right common carotid artery. After elliptical arteriotomy it was made end-to-side anastomosis with the distal stump of the internal jugular vein. The volume of aneurysms was calculated in a way that the value did not exceed on 27 times the value of the area of arteriotomy. After six days was performed angiography and microscopic analysis of aneurysms to assess patency, partial or total thrombosis of them. Results: There was a significant weight gain of swines in the time interval between the making of the aneurysm and angiography (p = 0.04). Aneurysmal patency was observed in 10 swines (83%). Wound infection occurred in 2 animals (16.6%) both with early onset 3 days after making of the aneurysm. After histological analysis of aneurysms, thrombus were founded partially occluding the light aneurysm in 9 animals (75%). In these animals it was observed that in average 9% of the aneurysmal lumen was filled with thrombus. Conclusion: The stable experimental model of carotid artey saccular aneurysm in swine using the internal jugular vein was developed.
175

Embolização com molas revestidas com copolímero e molas não revestidas em modelo experimental de aneurisma cerebral em suínos

Mossmann, Gabriel January 2008 (has links)
Objetivo: Desenvolver um modelo experimental de aneurisma cerebral em artéria de suínos. Secundariamente, avaliar o processo de organização do trombo e de formação de tecido fibrocelular dentro do aneurisma com o tratamento endovascular utilizando molas revestidas (Matrix) comparadas às sem revestimento (GDC). Materiais e Métodos: Em 10 suínos sadios, com peso variando entre 16 e 20 kg, sendo 6 machos e 4 fêmeas, foi realizada a cirurgia de formação de aneurisma nas carótidas bilateralmente, através de arteriotomia e anastomose término-lateral com segmento de veia jugular. O diâmetro médio dos aneurismas era de 3 mm (variação de 2 a 4mm). Procedia-se então ao tratamento endovascular dos aneurismas divididos do seguinte modo: grupo I, embolização do aneurisma da carótida esquerda com mola de platina (GDC); grupo II, embolização do aneurisma da carótida direita com mola de platina revestida com copolímero - PGLA 90/10 (Matrix). Após 14 dias, eram retiradas as lesões e analisadas microscopicamente, comparando-se a formação de trombo recente ou trombo organizado no interior de cada aneurisma. Para isso, foi criada uma escala de caracterização das fases do processo de trombose (Escores de 1 a 4). O Escore 1 era definido como a presença de trombo inicial ou recente; o Escore 2 era categorizado como a presença de leucócitos em diferenciação contendo fibrina e absorção das hemácias e plaquetas, porém intercalados com zonas contendo trombo recente. No Escore 3, observavase a presença de leucócitos em diferenciação contendo fibrina e no Escore 4, a presença de tecido fibrocelular contendo fibras de colágeno. A análise estatística foi realizada de modo pareado, através do Teste de Wilcoxon, sendo os dados processados no programa SPSS 12.0. O nível de significância mínimo adotado foi de 5%. Resultados: Um animal (macho) foi excluído do estudo devido à formação de abscesso cervical, restando, portanto, 9 animais (18 aneurismas para avaliação). Na análise do processo de organização do trombo, utilizou-se a graduação por escores, obtendo-se no grupo I, 88,8% de casos de trombo recente (Escore 1) e 11,1% de casos de trombo em organização ainda contendo coágulo (Escore 2). No grupo II, obteve-se 11,1% de casos com escore 1 , 11,1% com escore 2, 55,5% de casos de trombo organizado com tecido fibrocelular frouxo (Escore 3) e 22,2% de casos de tecido fibrocelular denso contendo colágeno (Escore 4). Houve diferença estatística a favor do grupo II, por meio do Teste de Wilcoxon (p=0,008). Conclusão: O modelo experimental de aneurisma de pequenas dimensões utilizado neste estudo foi adequado e permitiu a realização do tratamento endovascular testando dois tipos de molas. Por meio da análise histológica baseada em escala criada para avaliar a organização do trombo, pôde-se verificar diferença significativa a favor das molas com revestimento de copolímero. / Background and Objectives: To develop an experimental model in a pig that could be used for analysis of patency of cerebral aneurysms is the goal of this study. Adictionaly, it aims to evaluate the degree of thrombosis after embolization with two types of coils: copolymer-coated coils (Matrix) and uncoated platinum coils (GDC). Method: In a total of 10 Large-White pigs, small aneurysms (with a mean diameter of 3 mm) were created in both carotid arteries (6 males and 4 females) weighing 16 to 20 kg (mean: 18 kg). Embolization was performed with GDC platinum coils on the left side and with a coil coated with Matrix polymer on the right side. After 14 days, angiography was performed to confirm exclusion of the aneurysm. Before euthanasia with a lethal dose of potassium chloride, the carotid artery was removed in one piece, including the aneurysm. The specimens were cut into sections, including the mid portion of the aneurysm and the artery above and below the aneurysm, and stained with hematoxylin- eosin for histological analysis. A graduated scale with progressive scores ranging from 1 to 4 was used to evaluate the organization of the thrombus. Score 1 indicated clusters of platelets, white blood cells, and red blood cells; Score 2 showed the presence of differentiating white blood cells containing fibrin and absorption of red blood cells and platelets, interspersed with zones containing a recent thrombus; Score 3 corresponded to the presence of differentiating white blood cells containing fibrin, which characterized a loose fibrocellular tissue; and Score 4 indicated the presence of fibrocellular tissue containing collagen fibers, which characterized an incipient dense fibrocellular tissue The data were described as frequency and percentage using the Wilcoxon test for findings involving thrombosis scores. The data were analyzed using the SPSS 12.0 software, and the minimum significance level was set at 5%. Results: One animal (male) was excluded from the study due to abscess formation near the anastomosis. Therefore, 9 animals (18 aneurysms) were assessed. A score was used for analyzing the organization of the thrombus. In group I, 88.8% had score 1, 11.1% score 2, but no cases showed scores 3 and 4. In group II, 11.1% had score 1, 11.1% score 2, 55.5% score 3, and 22.2% score 4. The Wilcoxon test was applied, revealing a significant difference (p=0.008) between the scores for group I and group II in the course of 14 days. Conclusion: The experimental aneurysm developed in this study was suitable for assessing the patency of small aneurysms (measuring, on average, 3 mm) after coil embolization. The organization of the intra-aneurysmal thrombus after 14 days was verified using the progressive score, which indicated a significant difference between the group treated with the Matrix coil and that treated with GDC.
176

Características do olfato de pacientes pré e pós-tratamento cirúrgico para hemorragia subaracnóidea aneurismática

LIMA, Sandro Júnior Henrique 24 February 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-09-15T18:22:21Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO.pdf: 6914963 bytes, checksum: b59dc4afc22cc256f6af81abdcd285cc (MD5) / Made available in DSpace on 2016-09-15T18:22:21Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO.pdf: 6914963 bytes, checksum: b59dc4afc22cc256f6af81abdcd285cc (MD5) Previous issue date: 2016-02-24 / Introdução: Os aneurismas intracranianos trazem consequências importantes para o paciente acometido. A hemorragia subaracnóidea (HSA) possui uma forte correlação com aneurismas saculares e devido a sua gravidade e alta ocorrência de sequelas, o seu estudo merece importância. Uma alteração sensorial que pode esta relacionada à HSA é o déficit olfatório. Dentre os métodos de avaliação do olfato descritos, os quantitativos são ferramentas que podem ser utilizados a fim de garantir resultados mais fidedignos considerando o quadro clínico desses pacientes. Objetivos: Caracterizar o olfato de pacientes pré e pós tratamento cirúrgico para hemorragia subaracnóidea aneurismática. Método: Esta dissertação está composta por dois artigos. O primeiro constou de um artigo de revisão com título Métodos de avaliação do olfato em pacientes vítimas de hemorragia subaracnóidea: revisão sistemática. O segundo é um artigo original intitulado Avaliação do olfato na hemorragia subaracnóidea aneurismática antes e após o tratamento cirúrgico, neste foram estudados 15 adultos com hemorragia subaracnóidea aneurismática, atendidos no Hospital da restauração de Pernambuco, avaliados em três momentos distintos: Após a hemorragia, com uma semana de pós-operatório e com três meses de pós-operatório. A pesquisa foi iniciada após aprovação pelo Comitê de Ética em Pesquisa do hospital. Após a aplicação do Termo de Consentimento Livre e Esclarecido foi realizada a revisão do prontuário, entrevista com o participante e avaliação do olfato por meio de um teste de soluções aquosas, adaptado de outros estudos, construído pela farmácia escola da UFPE. Resultados: O primeiro artigo mostrou heterogeneidade nos métodos utilizados para avaliação do olfato na hemorragia subaracnóidea, como também no momento selecionado para aplicação das avaliações, com evidencias de déficit olfatório nesta população. Nos resultados provenientes do estudo original desta dissertação foi observado maior número de classificações olfatórias normais, além disso, não foi encontrada correlação significativa entre a pontuação olfatória com as seguintes variáveis (Idade, Intervalo em dias entre a hemorragia subaracnóidea e a avaliação olfatória, escolaridade e topografia do aneurisma). Não houve mudança significativa na pontuação olfatória após a cirurgia. Houve diferença estatística significativa na comparação entre a pontuação olfatória com uma semana de pós-operatório e com três meses de pós-operatório. Considerações finais: Os resultados deste estudo mostram a ocorrência de alteração olfatória após a hemorragia subaracnóidea aneurismática, assim como piora na classificação do olfato após a cirurgia. Foi observada melhora no olfato após três meses de pós-operatório, com significância estatística. Sugere-se a continuação de estudos com o tema, como também que façam investigação da percepção subjetiva do olfato visando o esclarecimento dos prejuízos que a alteração olfatória causa na vida dessa população. / Introduction: Intracranial aneurysms bring important consequences for the affected patient. The subarachnoid hemorrhage (HSA) has a strong correlation with saccular aneurysms and due to its gravity and high occurrence of sequels, its study deserves importance. A sensory change can this ASH-related is the olfactory deficit. Among the methods of valuation of smell described, are quantitative tools that can be used to ensure more reliable results considering the clinical picture of these patients.Objectives: Characterize the smell of patients before and after surgical treatment for aneurysmal subarachnoid hemorrhage. Method: This dissertation is composed of two articles. The first consisted of a review article with title Methods of evaluation of smell in victims of subarachnoid hemorrhage patients: a systematic review. The second is an original article entitled Olfactory evaluation in aneurysmal subarachnoid hemorrhage before and after surgery, this 15 were studied adults with aneurysmal subarachnoid hemorrhage, met at the Hospital da Restauração de Pernambuco, evaluated in three different moments: After the bleeding, a week after surgery and three months postoperatively. The search was started after approval by the Research Ethics Committee of the Hospital. After the application of informed consent was held to review the medical records, interview with the participant and evaluation of smell through a test of aqueous solutions, adapted from other studies, built by the Pharmacy School, Federal University of Pernambuco. Results: The first article showed heterogeneity of the methods used to evaluate the smell in aneurysmal subarachnoid hemorrhage and in the methods selected for application of evaluations, with evidence of olfactory deficits in this population. The results from the original study of this dissertation it was observed as many olfactory normal ratings, moreover, was not found significant correlation between olfactory score with the following variables (age, interval in days between the subarachnoid hemorrhage and the olfactory evaluation, education and topography of the aneurysm). There was no significant change in scoring olfactory after surgery. There was a statistically significant difference in the comparison between the olfactory score with a week after surgery and three months postoperatively. Final considerations: The results of this study show the occurrence of olfactory disfunction after aneurysmal subarachnoid hemorrhage, as well as worsens the classification of smell after surgery. Improvement was observed in the nose after three months postoperatively, with statistical significance. It is suggested a continuation of studies with the theme, but also to make the subjective perception of smell to identify the problems that the disfunction olfactory cause in this population´s life.
177

Niveis plasmaticos de vasopressina em cirugia de correção de aneurisma de aorta abdominal / Plasmatic levels of vasopressin in the4 corrective surgery of abdominal aorta aneurysm

Carvalho, Adriana Camargo 13 August 2018 (has links)
Orientadores: Sebastião Araujo, Ana Terezinha Guillaumon / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T22:15:18Z (GMT). No. of bitstreams: 1 Carvalho_AdrianaCamargo_M.pdf: 1640507 bytes, checksum: d217bd19f4b6097e48dac1bb2f824e35 (MD5) Previous issue date: 2009 / Resumo: Objetivos: Avaliar os níveis plasmáticos de vasopressina (AVP) em pacientes submetidos à correção cirúrgica não-complicada de aneurisma de aorta abdominal (AAA). Desenho: Estudo prospectivo, descritivo, observacional. Intervenções: Nenhuma. Local: Hospital de Clínicas da Unicamp. Métodos: A AVP plasmática foi mensurada por radio-imuno-ensaio em 22 pacientes não-consecutivos submetidos à correção cirúrgica convencional de AAA infra-renal, sob anestesia combinada (geral e epidural) nos seguintes tempos: pré-operatório (T0); 2h (T1) e 6h (T2) após o término da cirurgia; e nas manhãs do 1º (T3), 2º (T4) e 3º (T5) dia pós-operatório (PO). Algumas variáveis clínicas e laboratoriais de interesse foram registradas concomitantemente. Resultados: A idade média dos pacientes foi de 68,2±10,2 anos (variando de 49-82 anos), sendo 17 homens e 5 mulheres. Os níveis plasmáticos de AVP (média±DP pg/mL) estavam baixos e dentro da faixa de normalidade em T0 (1,4±0,7; controle), aumentando significativamente em T1 (62,6±62,9; p<0,001) e T2 (31,5±49,7; p<0,001), com uma queda exponencial a seguir, retornando aos níveis basais em T5 (2,1±3,8; p = NS). Correlações positivas e estatisticamente significativas foram encontradas entre a AVP e a glicemia, lactatemia e leucócitos sangüíneos, mas não com a pressão arterial sistêmica ou osmolaridade plasmática no PO. Conclusões: O padrão de aumento da AVP plasmática, com picos nas primeiras horas de PO nestes pacientes, sugere que esta resposta está diretamente relacionada ao trauma cirúrgico, mas não às alterações hemodinâmicas e da osmolaridade plasmática. A fisiopatologia deste padrão de resposta ao estresse é ainda obscuro, e merece investigações adicionais em procedimentos cirúrgicos gerais / Abstract: Objectives: To evaluate plasma vasopressin (AVP) levels in patients undergoing uncomplicated conventional abdominal aortic aneurysm (AAA) repair. Design: Prospective, descriptive, observational study. Interventions: None. Setting: A tertiary academic hospital at Campinas, Sao Paulo, Brazil. Methods: Plasma AVP concentrations were measured by radioimmunoassay in 22 nonconsecutive adult patients undergoing infra-renal AAA repair under combined general and epidural anesthesia at the following moments: pre-operative (T0); 2h (T1) and 6h (T2) after surgical procedure; and by the morning at the 1st (T3), 2nd (T4) and 3rd (T5) postoperative days. Some clinical and laboratory variables were concomitantly recorded. Results: Patients mean age was 68.2±10.2 years (ranging 49-82 years), with 17 males and 05 females. AVP plasma levels (mean±SD pg/mL) were low and within the normal range at T0 (1.4±0.7; control), showing a significant increase at T1 (62.6±62.9; p<0.001) and at T2 (31.5±49.7; p<0.001), with a marked progressive fall in the subsequent days, returning to basal levels at T5 (2.1±3.8; p = NS). Positive and statistically significant correlations were found between AVP levels and glycemia, lactatemia and white blood cells counts, but not with systemic arterial pressure or plasma osmolarity during postoperative period. Conclusions: The pattern of plasma AVP increasing, peaking during the 1st postoperative hours, suggests that this response is directly related to the surgical trauma, but not to hemodynamic and/or plasmatic osmolarity derangements. The pathophysiology of this pattern of stress response is still unclear, and deserves further investigation in general surgical procedures / Mestrado / Pesquisa Experimental / Mestre em Cirurgia
178

Análise dos pacientes submetidos a operação cardíaca para reconstrução ventricular esquerda na Unicamp = estudo retrospectivo / Surgical ventricular restoration at State University of Campinas : a retrospective study

Silveira Filho, Lindemberg da Mota, 1972- 18 August 2018 (has links)
Orientador: Orlando Petrucci Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T22:07:44Z (GMT). No. of bitstreams: 1 SilveiraFilho_LindembergdaMota_D.pdf: 1928782 bytes, checksum: 24dd8ac7d49f06f428575796e647fec2 (MD5) Previous issue date: 2011 / Resumo: Introdução: O infarto do miocárdio pode levar a importante dilatação do ventrículo esquerdo, com piora da sua função. Inúmeras técnicas tem sido descritas para restaurar o ventrículo esquerdo a seu formato original e identificar fatores associados a sobrevida a longo prazo. Objetivos: Descrever experiência cirúrgica com a reconstrução ventricular utilizando a cirurgia de Dor modificada com uso de uma prótese rígida (DM) e a pacopexia ("septal anterior ventricular exclusion - SAVE") e avaliar a sobrevida de acordo com o índice de EuroSCORE. Materiais e Métodos: Entre 1999 e 2007, uma coorte de 80 pacientes submetidos a cirurgia de reconstrução ventricular foram estudados. Houveram 53 pacientes submetidos a cirurgia de Dor modificada com uso de prótese rígida (grupo DM) e 19 submetidos a pacopexia (grupo SAVE). Todos os pacientes tiveram seus dados demográficos, ecocardiográficos e cineangiocoronariografia e ventriculografia analisados. Os pacientes foram classificados em relação ao formato do ventrículo esquerdo como tipos I, II ou III. Curvas de sobrevida de Kaplan-Meier e regressão logística de Cox foram realizadas para analisar a sobrevida após reconstrução ventricular esquerda em ambas as técnicas. Resultados: Mortalidade operatória compatível com o índice de EuroSCORE foi comparável em ambos os grupos. Os dois grupos foram semelhantes na maioria dos dados clínicos, porém o grupo DM apresentou maior número de pacientes com balão intra-aórtico no pré-operatório (5,7% vs. 0,0 %; P < 0,01). O grupo DM apresentou melhora na classe funcional de ICC da NYHA e na fração de ejeção no pós-operatório. As curvas de Kaplan-Meier de acordo com o formato do ventrículo esquerdo de todos os pacientes mostraram sobrevida comparável, com discreto aumento de sobrevida no tipo I. Análise da sobrevida atuarial global de Kaplan-Meier mostrou sobrevida equivalente com ambas as técnicas em 12 anos de seguimento (71,5 12,3 vs. 46,6 20,5 anos; P= 0,08). Análise de Kaplan-Meier de acordo com o EuroSCORE mostrou diferenças nas três categorias analisadas, 0 a 10 %, 11 a 49 % e maior que 50% de mortalidade esperada em 12 anos de seguimento (70,9 16,2 vs. 67,5 12,7 vs. 53,0 15,5; P = 0,003). Conclusões: As operações de reconstrução ventricular esquerda realizadas por ambas as técnicas demonstraram resultados consistentes, com melhora da classe funcional de ICC de NYHA durante o período de seguimento. A técnica de DM demonstrou melhora na fração de ejeção e restauração do formato ventricular elíptico. A sobrevida foi semelhante para todos os tipos de formato ventricular e para ambas as técnicas aplicadas. O índice de EuroSCORE se revelou útil para análise de sobrevida tardia nas cirurgias de reconstrução ventricular / Abstract: Introduction: Myocardial infarction might result in dilated left ventricle and numerous techniques were described to restore the original left ventricle shape and identify tools for late survival assessment. The aim of this study is to describe our experience with surgical ventricular restoration (SVR) using modified Dor (MD) procedure using a rigid prosthesis and septal anterior ventricular exclusion (SAVE) procedure and evaluate the EuroSCORE index for late follow up survival. Material and Methods: Between 1999 to 2007, a cohort of 80 patients who underwent left ventricle restoration were evaluated. There were 53 patients who underwent modified Dor procedure with a rigid prosthesis (MD group) and 19 who underwent septal anterior ventricular exclusion procedure (SAVE group). All patients were analyzed for demographic, echocardiograph and catheterization data and were classified according to their left ventricle shape as type I, II or III. Kaplan-Meier and Cox proportional hazard ratio regressions analyses were performed to assess survival after ventricular restoration surgery in both techniques. Expected surgical mortality according to EuroSCORE index was evaluated after 12 years of follow up. Results: Operative mortality was comparable in both groups ranked by EuroSCORE index. Both groups were comparable in the majority of clinical data, however the MD group showed more patient using intra aortic balloon pump before the surgery (5.7% vs. 0.0 %; P < 0.01). MD group showed improvement on NYHA functional class and ejection fraction. Kaplan-Meier analyses by left ventricle shape with all patients showed comparable survival, with a slight higher survival with type I. Kaplan-Meier analyses with all mortality showed equivalent survival curves with both techniques after 12 years of follow up (71.5 12.3 vs. 46.6 20.5 years; P = 0.08). Kaplan-Meier analyses by ranked EuroSCORE for all patients showed differences among the three ranked categories, i.e., 0 to 10 %, 11 to 49 % and higher than 50% expected surgical mortality after 12 years of follow up (70.9 16.2 vs. 67.5 12.7 vs. 53.0 15.5; P = 0.003). Conclusions: SVR performed by both techniques showed consistent results with significant improvement in NYHA functional class along follow up period. The MD procedure showed improvement in ejection fraction and left ventricle reshaping after long term follow up. Survival was comparable for all ventricular types and for both techniques applied. EuroSCORE index is a useful index for late survival assessment for surgical ventricular restoration / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências
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Angiotomografia cerebral 3D no manejo precoce da hemorragia subaracnóide aguda / 3D computed tomography angiography in the management of acute aneurismal subarachnoid hemorrhage

Kaleff, Paulo Roland, 1976- 21 August 2018 (has links)
Orientador: Donizeti Cesar Honorato / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T22:21:39Z (GMT). No. of bitstreams: 1 Kaleff_PauloRoland_D.pdf: 1126011 bytes, checksum: 23cb0c05a54790e4896ebd16d8754941 (MD5) Previous issue date: 2012 / Resumo: A angiotomografia cerebral 3D (ATC) passou a ser uma alternativa à angiografia por subtração digital (ASD) para a detecção dos aneurismas intracranianos. As recomendações atuais para a hemorragia subaracnóidea aguda (HSA) secundária à ruptura de aneurismas intracranianos incluem o tratamento definitivo precoce. O objetivo primário deste estudo foi o de avaliar a contribuição da ATC para a diminuição do tempo entre o diagnóstico da HSA e o diagnóstico do aneurisma, bem como para a diminuição do tempo entre a admissão do paciente e a exclusão do aneurisma, quando comparada com a ASD. Como objetivo secundário buscou-se comparar a sensibilidade de ambos os métodos diagnósticos, comparar os resultados clínicos de dois grupos de pacientes diagnosticados pala ATC e/ou pela ASD e avaliar a contribuição da ATC na abordagem cirúrgica aos hematomas secundários à ruptura de aneurismas intracranianos. Uma análise retrospectiva foi conduzida cobrindo 100 pacientes admitidos com HSA e diagnosticados para aneurisma via ATC (n=60) ou via ASD (n=40). Os dados coletados foram divididos de acordo com o método diagnóstico utilizado inicialmente para a detecção do aneurisma. Os tempos transcorridos entre o diagnostico da HSA e o diagnóstico do aneurisma foi consistentemente inferior para os pacientes submetidos à ATC (p<0.000005). Em relação ao tempo transcorrido entre a admissão e o tratamento definitivo, 70% das ocorrências para pacientes submetidos à ATC ficaram abaixo de 72 horas enquanto 60% das ocorrências para pacientes submetidos à ASD excederam 72 horas (p<0.003). A sensibilidade da ATC para aneurismas rotos foi de 0, 967 e para todos os aneurismas de 0, 931. A maioria dos casos submetidos à ATC antes da drenagem do hematoma teve o aneurisma tratado no mesmo procedimento cirúrgico. A ATC contribuiu para a redução do tempo entre o diagnóstico da HSA e o diagnóstico do aneurisma, bem como para a redução do tempo entre a admissão e o tratamento definitivo do aneurisma. A sensibilidade dos métodos foi equivalente, especialmente para os aneurismas rotos, em exames tecnicamente satisfatórios. Nos casos de hematomas secundários à ruptura de aneurismas intracranianos, a realização da ATC previamente à abordagem cirúrgica contribuiu para o tratamento definitivo do aneurisma no mesmo procedimento cirúrgico da drenagem do hematoma / Abstract: Due to its technical advancements, 3D cerebral computed tomography angiography (CTA) is increasingly being considered as an alternative to digital subtraction angiography (DSA) in the detection of intracranial aneurysms. Actual guidelines for acute subarachnoid hemorrhage (aSAH) recommend early definitive treatment. The primary goal of this study was to evaluate the contribution of CTA in shortening of time span between the diagnosis of the aSAH and the diagnosis of the aneurysm, as well as the shortening of time span between admission and definitive aneurysm treatment, when compared to DSA. As secondary goals we aimed at comparing the sensitivity of both methods, at comparing the clinical results between two studied patient groups diagnosed by CTA and/or by DSA and at evaluating the contribution of CTA to the surgical approach to intracranial hematomas secondary to aneurysm rupture. A retrospective analysis was performed covering 100 patients admitted with aSAH and diagnosed with intracranial aneurysms either by CTA (n=60) or by DSA (n=40). The data collected for both groups were separated according to the method used for the initial diagnosis of the aneurysm. The time spans between the diagnosis of the aSAH and the diagnosis of the aneurism were consistently smaller for CTA patients than for DSA patients (p<0.000005). Regarding the time spans between the admission and the final treatment, 70% of the outcomes for CTA patients remained below 72 hours and 60% of the outcomes for the DSA group exceeded 72 hours (p<0.003). The sensitivity for ruptured aneurysms was 0,967 and for all aneurysms 0,931. In the majority of cases where a CTA was performed previously to the hematoma evacuation the aneurysm could be treated in the same surgical procedure. CTA contributed to the shortening of the time elapsed between the diagnosis of the aSAH and the diagnosis of the aneurysm, as well as to the shortening of the time elapsed between admission and definitive treatment. The sensitivity of the methods was equivalent, especially for ruptured aneurysms, in technically satisfactory CTA. The use of CTA did not have a negative impact in the clinical outcome or the treatment. CTA performed previously to hematoma evacuation contributed to the definitive treatment of the aneurism in the same surgical approach / Doutorado / Neurologia / Doutor em Ciências Médicas
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Trafic monocytaire dans l'anévrisme de l'aorte abdominale / Monocyte trafficking in abdominal aortic aneurysm

Mellak, Safa 10 November 2014 (has links)
Les maladies cardiovasculaires sont la première cause de mortalité dans le monde et voient leur incidence augmenter avec l’expansion de leurs principaux facteurs de risque, tels que le vieillissement, l’obésité et le diabète. Parmi ces maladies l’anévrisme de l’aorte abdominale (AAA), dont on sait aujourd’hui que le système immunitaire favorise le développement. Il est parmi les pathologies les plus courantes de l’aorte abdominale et représente un problème de santé publique. Le rôle des macrophages dans l’AAA a été récemment mis en évidence. Ces cellules inflammatoires sont les plus représentées dans l’adventice anévrismale, et ont tendance à s’accumuler au cours du temps dans l’AAA. Des données récentes montrent que leur accumulation est particulièrement accrue dans les premiers jours de la formation de l’AAA chez la souris, et que l’inhibition de la voie CCR2/MCP1 ou la déplétion précoce des monocytes circulants ont un effet protecteur. Il semble donc essentiel de comprendre les mécanismes d’infiltration des monocytes lors de l’initiation et du développement de l’AAA. Mon travail de thèse se focalise sur le rôle des sous-types monocytaires et l’impact de leur trafic sur le développement de l’AAA. En utilisant un modèle d’induction d’anévrisme chez des souris ApoE-/-, nous avons montré que l’angiotensine-II (Ang II) entraine la mobilisation des monocytes ‘Ly-6Chigh’, et des monocytes ‘Ly-6Clow’ à un moindre degré, à partir de la rate, puis leur recrutement au niveau de l’aorte. La splénectomie ou la déficience en lymphocyte B inhibe cette mobilisation monocytaire et protège de l’anévrisme. En revanche, la reconstitution de souris immuno-déficientes Apoe-/-Rag2-/- par des splénocytes totaux, contrairement aux splénocytes déplétés en lymphocytes B, restaure la mobilisation monocytaire et restitue la susceptibilité de ces souris à l’AAA. Cette thèse apporte de nouveaux indices sur les événements précoces impliqués dans la formation d’AAA, en mettant l’accent sur le rôle du réservoir monocytaire splénique dans ce processus. Elle identifie également une fonction jusque-là méconnue des lymphocytes B dans la mobilisation rapide et transitoire des monocytes en réponse à l’Ang II. Il conviendra par la suite d’identifier les mécanismes moléculaires sous-jacents à ces interactions, ce qui devrait permettre d’envisager de nouvelles voies thérapeutiques visant à moduler l’effet de ces types cellulaires dans l’AAA. / Cardiovascular diseases are the first cause of mortality around the industrialized world with a continuous increase in their incidence along with the expansion of the major risk factors such as aging, obesity and diabetes. In abdominal aortic aneurysm (AAA), the presence of inflammatory infiltrates, and particularly monocytes/macrophages, has underscored the contribution and importance of immuno-inflammatory responses in aneurysmal degeneration. It is one of the most common diseases of the abdominal aorta and presents a major health problem. The importance of macrophages has recently been highlighted by a number of evidence, which are the main population observed within the site of aneurysm, are believed to derive from circulating monocytes although no direct evidence has been provided to date. Recent evidence has shown that their accumulation is particularly enhanced in the early onset of AAA in mice, and that the inhibition of CCR2/ MCP1 signaling as well as the early depletion of circulating monocytes, are protective. Hence, it seems crucial to understand the mechanisms of monocyte recruitment in the initiation and progression of AAA. In this PhD project with a particular interest in abdominal aortic aneurysm, we were particularly interested in understanding the trafficking behavior of monocyte subsets in AAA and their role in disease pathogenesis. Using a mouse model of aneurysm induction in ApoE-/- mice, we showed that Ang II triggered the mobilization of Ly-6Chigh, and to a lesser extent Ly-6Clow monocytes, from the spleen and their consequent recruitment in the aorta. Spleen removal or B lymphocyte deficiency in Apoe-/- mice similarly impaired early monocyte mobilization in response to Ang II and protected against AAA development, independently of blood pressure. Reconstitution of Apoe-/- Rag-/- mice with total splenocytes but not with B-Cell depleted splenocytes restored monocyte mobilization in response to Ang II and enhanced susceptibility to AAA. Taken together, this study provides novel mechanistic insights on the early events involved in AngII-induced AAA formation. It highlights the role of the splenic monocyte reservoir in this process and identifies an intriguing role for B lymphocytes in mediating AngII-induced early and transient mobilization of splenic monocytes. Nevertheless, further understanding of the molecular mechanisms that underlie such interactions is likely to lead to the identification of effective therapeutic targets.

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