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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.
411

Revisão Sistemática com meta-análise da indicação do tratamento endovascular na Síndrome de Cockett em pacientes com e sem trombose da veia ilíaca esquerda. / Systematic Review with meta-analysis of the indication of the endovascular treatment in the Cockett Syndrome in patients with and without thrombosis of the common left iliac vein.

Rodrigues, Lenize da Silva [UNESP] 01 September 2017 (has links)
Submitted by LENIZE DA SILVA RODRIGUES (nize_silva@hotmail.com) on 2017-09-27T19:16:54Z No. of bitstreams: 1 DISSERTACAO DE MESTRADO PESQUISA CLINICA - LENIZE DA SILVA RODRIGUES.pdf: 2672614 bytes, checksum: 59d7f6f68213dfaccdca11f5c0b0f7bf (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-28T14:36:32Z (GMT) No. of bitstreams: 1 rodrigues_ls_me_bot.pdf: 2672614 bytes, checksum: 59d7f6f68213dfaccdca11f5c0b0f7bf (MD5) / Made available in DSpace on 2017-09-28T14:36:32Z (GMT). No. of bitstreams: 1 rodrigues_ls_me_bot.pdf: 2672614 bytes, checksum: 59d7f6f68213dfaccdca11f5c0b0f7bf (MD5) Previous issue date: 2017-09-01 / A Síndrome de Cockett (SC) se deve a uma compressão extrínseca da veia ilíaca comum esquerda (VICE) pela artéria ilíaca comum direita (AICD). Em consequência há o desenvolvimento de lesões intraluminais. Este cruzamento entre a artéria e a veia é considerada uma condição anatômica usual, porém em cerca de 29% da população ela pode torna-se sintomática. Os sintomas causados pela SC são: edema, dor, claudicação venosa, hiperemia, varizes e úlceras, podendo evoluir também com complicações como trombose venosa, embolia pulmonar, e mais raramente com Flegmasia Cerúlea Dolens. Até hoje não existe consenso sobre a melhor forma de tratar pacientes com SC na presença ou ausência de trombose da VICE, dividindo as opiniões se deve ser feito o tratamento clínico e/ou endovascular. Preferencialmente alguns autores optam pelas técnicas endovasculares em todos os casos e sugerem que a mesma seja realizada, na tentativa de melhorar a fluxo venoso evitando as complicações tardias. Á curto prazo, os resultados do tratamento endovascular com stents, tem mostrado excelente perviedade, embora estejam alguns deles associados ao uso de antiagregantes, anticoagulantes e ao tratamento clinico convencional com a meia elástica. Objetivo: O presente estudo teve a finalidade de comparar os resultados de perviedade e a taxa de complicações ocorridas em pacientes portadores da SC, tratados com angioplastia e stent, na presença e ausência de trombose da VICE, utilizando a Revisão Sistemática e Meta-análise de estudos observacionais. Método: Foram utilizadas as recomendações do manual Cochrane Handbook for Intervention Reviews produzido pela Cochrane que orienta a produção de revisões sistemáticas utilizando como referência para a escolha do método. A produção desta dissertação e manuscrito foi baseada no MOOSE statement para garantir que todas as etapas do estudo sejam reportadas claramente. As bases de dados utilizadas foram: Medline, EMBASE, LILACS, Scopus, Scielo, Pubmed e, Web of Science. A data da última busca foi 06 de abril de 2017. Esta pesquisa incluiu estudo de 2 grupos principais, tratados com angioplastia e stent: no G1: foram incluídos pacientes com a SC ausência trombose VICE e no G2 foram incluídos pacientes com SC presença de trombose da VICE. Resultados: De 250 artigos foram selecionados 3 estudos comparativos observacionais, sendo o número total de pacientes avaliados igual a 243. Nestes trabalhos selecionados foram associados ao tratamento endovascular o uso de antiagregantes plaquetários, anticoagulantes durante o período 3 a 12 meses e o uso da meia elástica. A patência primária, respectivamente, no G1 e G2 foi de e 93,4% e 89,2% (OR 0.55, 95% IC [0.15, 2.06], P= 0.37; I2=29%, P=0.24). E a patência secundária, respectivamente, de G1 e G2 foi de 93.5% e 82.06% (OR 0.50, 95% IC [0.05, 4.72], P= 0.54; I2=69%, P=0.04). Embora não estatisticamente significante, observa-se uma tendência em ocorrer maior patência nos pacientes do G1. Em relação ás complicações no total, houve tendência maior no G2 em relação ao G1. Conclusão: Os resultados obtidos neste estudo de revisão sistemática, mostraram que o tratamento endovascular é eficaz em ambos os grupos à curto prazo e longo prazo, mas, sugere que no grupo 1 a perviedade é discretamente melhor que no grupo 2, com menores complicações. / The Cockett Syndrome (CS) is due to an extrinsic compression of the common left iliac vein (CLIV) by the common right iliac artery (CRIA). Consequently, there is a development of intraluminal lesions. This crossing between the artery and the vein is considered a usual anatomic condition; however, in about 29% of the population it may become symptomatic. The symptoms caused by the CS are: edema, pain, venous claudication, hyperemia, varicose veins e ulcers, being possible also to evolve with complications such as venous thrombosis, pulmonary emboli and more rarely with Flegmasia Cerúlea Dolens. Until today there´s no consensus about the best way to treat patients with CS in either the presence or the absence of CLIV thrombosis, it has been dividing opinions whether the clinical or the endovascular treatment should be done. Preferably, some authors choose the endovascular techniques in all cases and suggest that it be performed, in the attempt of improving the venous flow thus avoiding later complications. In short term the results of the endovascular treatment with stents, have shown excellent patency, although some of them are associated to the use of antiplatelet, anticoagulants and to the conventional clinical treatment with compression stocking. Objective: the present study had as goal to compare the results of the patency and the complication rate occurred in patients bearing the CS, treated with angioplasty and stent, in the presence and absence of the CLIV thrombosis, using the Systematic Review and Meta-Analysis in the observational studies. Method: It has been used the recommendations of the manual Cochrane Handbook for Intervention Reviews which orients the production of systematic reviews using as reference for the choice of the method. The production if this dissertation and manuscript has been based on the MOOSE statement to assure that all phases of the study be reported with clarity. The data bases used were: Medline, EMBASE, LILACS, Scopus, Scielo, Pubmed and, Web of Science. The date of the last search was April 6th 2017. This research includes the study of two main groups, both treated with angioplasty and stent: in the G1: it has been included patients with CS without CLIV thrombosis and in the G2: it has been included patients showing CS without CLIV thrombosis. Results: From 250 articles, it has been selected three comparative observational studies, being the total number of analyzed patients equal to 243. In these selected works it has been associated the use of antiplatelet, anticoagulants during the period from 3 to 12 months and the use of the compression stocking. The primary patency, respectively, in G1 and G2 has been of 93.4% and 89.2% (OR 0.55 (95% IC [0.15, 2.06], P= 0.374; I2=29%, P=0.24). And the secondary patency, respectively, in G1 and G2 has been of 93.5% and 82.06% (OR 0.50, 95% IC [0.05, 4.72], P= 0.54; I2=69%, P=0.04). Even though statistically not relevant in both patencies, it can be observed a tendency in the occurrence of a greater patency in patients from G1. In relation to the complications in the total, there has been difference being greater G2 in relation to the G1. Conclusion: The results obtained in the study of systematic review, have shown that the endovascular treatment is effective in short and long terms, but it suggests that in group 1 the patency is discreetly greater than in group 2, with less complications.
412

Valor do teste de dosagem do Dímero - D plasmático no diagnóstico do tromboembolismo venoso agudo / Value of measure plasmatic D Dimer test to diagnosis of the acute thrombolism venous

Luciana Pereira de Almeida de Piano 29 October 2007 (has links)
Introdução: A doença tromboembólica é um distúrbio complexo multicausal com sinais e sintomas inespecíficos, confundindo-se com outras enfermidades. Devido à sua gravidade buscam-se estratégias objetivando obter um diagnóstico precoce. O teste de dosagem do dímero - D plasmático parece ser uma alternativa para exclusão do diagnóstico de tromboembolismo venoso agudo. Objetivo: Avaliar o valor do teste de dosagem de dímero - D plasmático, utilizando o método Enzyme Linked Fluorescent Assay (ELFA), na rotina diagnóstica de tromboembolismo venoso agudo. Métodos: Em 89 pacientes com sinais e sintomas sugestivos de tromboembolismo pulmonar e/ou trombose venosa profunda foram realizadas dosagens do dímero - D pela técnica ELFA no equipamento VIDAS® - BioMérieux. Foram calculados os valores da sensibilidade, especificidade, valores preditivos positivo e negativo e acurácia do teste, bem como a curva ROC da amostra estudada. Todos os pacientes foram submetidos a exame por imagem para confirmação do evento tromboembólico agudo. Foi calculado o índice kappa para analisar o resultado do teste dímero - D versus resultados de exames por imagem. Resultados: Entre os 89 pacientes estudados (média de idade 54,3 anos; 51 mulheres), 36 (40,4%) apresentaram TEV e 53 não apresentaram trombose aguda (59,6%). Entre os pacientes sem trombose aguda 15 (28,3%) apresentaram resultado de dímero - D negativo. Todos pacientes com trombose apresentaram resultado de dímero - D positivo. O teste apresentou sensibilidade de 100%; especificidade de 28,3%; valor preditivo positivo de 48,6%; valor preditivo negativo de 100% e exatidão de 57,3%. A ASC para a amostra total estudada foi igual a 0,734, indicando que o teste é um bom preditor de trombose aguda. O valor do índice kappa para a amostra total foi igual a 0,24 (p<0,001), indicando uma concordância fraca entre dímero - D e diagnóstico confirmatório de trombose. Conclusão: A dosagem do dímero - D pelo método ELFA foi capaz de excluir o diagnóstico de tromboembolismo venoso agudo nessa amostra estudada. Os resultados obtidos nessa amostra estudada permitiram concluir que o uso do teste dímero - D em pacientes com suspeita de tromboembolismo venoso revelou alta sensibilidade no diagnóstico dessa enfermidade. / Introduction: The thromboembolic disease is a multicausal complex disturb with signals and symptoms that confusing itself with other diseases. Because its gravity strategies search objecting to get a faster diagnosis. The measure plasmatic D dimer test seems to be an alternative for exclusion of the diagnostic of acute venous thromboembolism. Objectives: To evaluate the value of the measure plasmatic D dimer test, using the method Enzyme Linked Fluorescent Assay (ELFA), in the diagnostic of acute venous thromboembolism. Methods: In 89 patients with signals and symptoms suggestive of pulmonary thromboembolism and/or deep vein thrombosis had been carried through measure D dimer by technique ELFA equipment VIDAS® - BioMérieux. The values of sensibility, accuracy specificity, predictive values positive and negative and of the test had been calculated, as well as curve ROC of the sample studied. All the patients had been submitted the image exams for the confirmation of the acute thromboembolism event. It was calculated kappa ratio to compare D dimer test results with image exams results. Results: Between 89 studied patients (mean of age 54.3 years; 51 women), 36 (40.4%) they had presented and 53 had not presented acute thrombosis (59.6%). It enters the patients without acute thromboembolism 15 (28.3%) had presented resulted negative of D dimer. All patients with thrombosis had presented resulted positive of D dimer. The test presented 100% sensibility; 28.3% of specificity; positive predictive value was 48.6%; 100% of negative predictive value and accuracy value was 57.3%. The area under the curve (AUC) to total sample studied was 0.734, it was showed that the test have a good prediction to acute thrombosis. The kappa ratio value was 0.24 (p<0.001) showing a bad concordat n to thrombosis diagnostic. Conclusion: The measure of D dimer by method ELFA was able to exclude the diagnostic of acute venous thromboembolism in this sample studied. The results obtained in this sample studied let to conclude that the D dimer test in patients with suspected of acute thromboembolism presented high sensibility to diagnostic of this disease.
413

Estudo comparativo do uso do antiagregante plaquetário e anticoagulante oral na profilaxia de trombose em pacientes submetidos à operação cavopulmonar total com tubo extracardíaco: análise ecorcardiográfica, angiotomográfica, cintililográfica, laboratorial e clínica / Comparative trial of the use of antiplatelet and oral anticoagulant in thrombosis prophylaxis in patients undergoing total cavopulmonary operation with extracardiac conduit: echocardiographic, tomographic, scintigraphic, clinical and laboratory analysis

Cristiane Felix Ximenes Pessotti 26 November 2013 (has links)
Estudo prospectivo e randomizado de 30 pacientes, submetidos a derivação cavopulmonar total com tubo extracardíaco. Os dados refletem o período de 2008 a 2011, com seguimento de dois anos, por meio de avaliação clínica, laboratorial, ecocardiográfica, angiotomográfica e cintilográfica. Neste estudo, procuramos comparar a eficácia do ácido acetil salicílico (AAS) e da Varfarina na profilaxia da trombose na população estudada. Para tanto, analisamos alterações nos fatores de coagulação (VII, VIII e Proteína C ); ou nos dados clínicos que predispusessem a ocorrência de trombo no pós-operatório. Além disso, no pós-operatório, após a randomização (15 pacientes randomizados para receber Varfarina, Grupo I, e 15 pacientes randomizados para receber AAS, Grupo II), estudamos a interferência da fenestração na ocorrência de trombo; alterações hemodinâmicas que pudessem contribuir com a ocorrência de trombo (fluxo lento pelo tubo extracardíaco), por meio de ecocardiograma transesofágico realizado com até 10 dias de pós operatório, 3, 6, 12 e 24 meses de pós operatório. A presença do fenômeno tromboembólico era pesquisada, além dos ecocardiogramas acima citados, por meio de consultas clínicas realizadas com a mesma periodicidade e que avaliavam, ainda, efeitos colaterais ou complicações no uso de cada uma das drogas. Avaliamos também a viabilidade e aderência ao uso de cada uma delas. O seguimento contou igualmente com a realização de angiotomografia aos 6, 12 e 24 meses de pós-operatório para avaliação de alterações na parede interna do tubo, bem como trombos e cintilografia pulmonar, ventilação-perfusão para avaliar possível tromboembolismo pulmonar. Durante o seguimento, ocorreram dois óbitos, ambos no grupo em uso de Varfarina. Ao todo, durante os dois anos de seguimento, 33,3% dos pacientes apresentaram fenômeno tromboembólico. Sendo que, entre os paciente em uso de AAS, 46,7% apresentaram tal complicação e 20% entre os pacientes em uso de Varfarina (p=0,121). Com relação a avaliação pré-operatória, a ocorrência prévia de trombo e baixos níveis de proteína C da coagulação foram os únicos fatores que influenciaram no tempo de sobrevida livre de trombo, com valores de p de 0,035 e 0,047 respectivamente. Ao final de dois anos de seguimento, na avaliação angiotomográfica, 35,7% dos pacientes em uso de AAS tinham material hiper-refringente depositado em tubo extracardíaco com espessura superior a 2mm ( p= 0,082). Já na avaliação por cintilografia de ventilação-perfusão, dois pacientes apresentaram sinais de tromboembolismo pulmonar, ambos em uso de AAS (p=0,483), e um deles com evolução desfavorável do circuito tipo Fontan. Com relação a segurança e aderência ao tratamento, cinco pacientes tiveram dificuldade de aderência (só viabilizada por tratar-se de protocolo de estudo), entre eles, quatro em uso de Varfarina e apresentando INR variando de 1 a 6,4. Para comprovação numérica, com força estatística dos dados encontrados, uma força tarefa deve ocorrer para que se consiga um grupo maior de pacientes incluídos neste estudo. No entanto, a diferença entre os dois grupos na evolução livre de trombo nos dois primeiros anos de pós-operatório não pode, e nem deve, ser ignorada / Prospective randomized trial of 30 patients who had undergone total cavopulmonary anastomosis via an extracardiac conduit. The data reflect the period between 2008 and 2011, with two-year follow-up, through clinical, laboratorial, echocardiographic, angiotomographic, and scintigraphic assessment. In this study, we aimed to compare the efficiency of ASA (Aspirin) and Warfarin in the preventive treatment of thrombosis in the tried population. For such, we\'ve analyzed changes in coagulation factors (VII, VIII and Protein C) or in the clinical data which would predispose the occurrence of postoperative thrombus. Moreover, during postoperative care, after randomization (15 patients randomly selected to be trated with Warfarin, referred to as Group I, and 15 patients randomly selected to be treated with ASA, referred to as Group II), we also studied the influence of fenestration in the occurrence of thrombus; hemodynamic variations which could contribute to the occurrence of thrombus (slow blood flow in the extracardiac conduit), with postoperative transesophageal echocardiogram being performed within 10 days, and thereafter 3, 6, 12 and 24 months. Besides the echocardiograms aforementioned, the presence of thromboembolic events was sought after by clinical appointments taking place with the same frequency, which evaluated, apart from thromboembolism, side effects or complications from the usage of each of the drugs. We\'ve also evaluated the compliance to and feasibility of each of them. Postoperative angiotomography was also performed during the follow-up, within 6, 12 and 24 months, for the evaluation of changes on the inside wall of the extracardiac conduit, as well as thrombi, and pulmonary ventilation/perfusion scintigraphy for assessment of pulmonary thromboembolism possibility. During the follow-up, two deaths were registered, both in the group being treated with Warfarin. Overall, in the two-year follow-up, 33,3% of the patients presented thromboembolic events. Among the group being treated with ASA, 46,7% presented such complication, whereas in the group being treated with Warfarin, 20% had the same complication (p=0,121). Regarding the preoperative evaluation, prior occurrence of thrombus and low levels of coagulation factor Protein C were the only variables which influenced living time without thrombus, with p-values of 0,035 and 0,047. At the end of the two-year follow-up, in the angiotomographic evaluation, 35,7% of patients treated with ASA presented material accumulation inside the extracardiac conduit, with over 2mm of thickness (p=0,082). As for the ventilation/perfusion scintigraphy, two patients presented traces of pulmonary thromboembolism, both treated with ASA (p=0,483), one of whom with unfavorable development of the Fontan circuit. Concerning safety and compliance to the treatment, five patients had difficulty to comply with the treatment (only viable for its trial nature), among those, four under treatment with Warfarin and presenting INR values ranging from 1 to 6,4. For quantitative verification, providing statistic value to the data, an effort must be made for a larger number of patients to be gathered and tried with this treatment. However, the difference in results concerning thrombus-free recovery between the two groups during the two years following surgery cannot, and must not, be ignored
414

O fator de von Willebrand, ligação com fator VIII e estudo da atividade da ADAMTS-13 em pacientes com síndrome antifosfolípide primária / Study of von Willebrand factor activity, binding with factor VIII and ADAMTS-13 activity in patients with primary antiphospholipid syndrome

Natalia Mastantuono Nascimento de Vita 09 December 2014 (has links)
A Síndrome Antifosfolípide (SAF) é uma doença autoimune na qual há presença de anticorpos antifosfolípides [anticoagulante lúpico (AL), anticardiolipina (ACL), anti-beta2glicoproteína I (a-beta2GPI)]. É caracterizada por eventos trombóticos e/ou perdas gestacionais de repetição. Existe um ambiente pró-coagulante na SAF, pois os antifosfolípides (AFL) são capazes de induzir disfunção endotelial aumentando a expressão de moléculas de adesão como o fator de von Willebrand (FVW). Entre os inúmeros elementos envolvidos neste processo, o FVW e a relação com: sua principal enzima proteolítica, a ADAMTS-13, e com o FVIII são relativamente menos conhecidos. Os objetivos deste estudo foram: 1-verificar alterações no endotélio de pacientes com SAF primária (SAFP), através do marcador de lesão endotelial, o FVW, da ADAMTS-13 e do FVIII, avaliando a concentração antigênica, a atividade e a correlação entre estas proteínas; 2- Verificar se alguma destas variáveis é capaz de diferenciar os tipos de eventos trombóticos ocorridos nestes pacientes e se a presença dos AFL influenciam estas proteínas. O estudo, do tipo transversal, envolveu 39 pacientes com SAF primária, com idade mediana de 43 anos, em tratamento no ambulatório de Reumatologia do Hospital das Clínicas, e 39 controles sadios doadores da Fundação Pró-Sangue Hemocentro de São Paulo, pareados por sexo e idade com os pacientes. Os títulos de ACL e a-beta2GPI, as determinações antigênicas e de atividade das proteínas FVW, ADAMTS-13, FVIII e PF4 foram realizados por ELISA, e a atividade do FVIII foi determinada pelo método cromogênico. A análise das subunidades do FVW foi realizada por Western immunoblotting. AL foi detectado utilizando ensaios de coagulação de acordo com as recomendações da Sociedade Internacional de Trombose e Hemostasia. Os resultados foram apresentados em: 1- pacientes SAFP e controles, e 2- pacientes SAFP agrupados em relação ao tipo de evento e ao tipo de AFL presente. Os pacientes apresentaram aumento da concentração antigênica do FVW (74±6 x 69±11 UI/dL; p=0,016), ADAMTS-13 (1,3±0,34 x 0,82±0,12 Ug/mL; p < 0,0001), FVIII (106±19 x 91±15 UI/dL; p=0,0003),da ligação FVW:FVIII (144±17 x 134±20%; p=0,082) e da atividade do FVIII (117±38 x 98±30%; p=0,0021) comparado aos controles. O PF4 apresentou-se diminuído nos pacientes em relação aos controles (96±12 x 101±8 UI/mL; p=0,014). Os pacientes com trombose arterial apresentaram correlação positiva e significante entre a atividade e o antígeno do FVW (r=0,468; p=0,028) e da ADAMTS-13 (r =0,635; p=0,001); os pacientes com trombose venosa apresentaram esta correlação positiva e significante na ADAMTS-13 (r=0,635; p=0,001). Quando os pacientes foram analisados pelo tipo de antifosfolípide, não se observou diferenças nas variáveis estudadas. Os pacientes com SAFP parecem apresentar disfunção endotelial. No entanto, aparentemente existe um mecanismo de equilíbrio para evitar a formação de um novo trombo. O papel do FVW e a sua relação com a ADAMTS-13, em diferentes doenças, ainda é relativamente pouco conhecido, mas está sendo apontado como importante na patogênese de estados pró-trombóticos como os presentes em pacientes com SAF / Antiphospholipid syndrome (APS) is an autoimmune disease, characterized by vascular thrombosis and /or pregnancy morbidity, in association with antiphospholipid antibodies (aPL) (lupus anticoagulant (LA), anticardiolipin (ACL), anti-beta2glicoprotein I (a-beta2GPI). Antiphospholipid (APL) seems to induce endothelial dysfunction by increasing the expression of adhesion molecules such as von Willebrand factor (VWF). This results in a prothrombotic state in APS. Among the several elements involved in this process, some are relatively less known, such as VWF and its relationship with ADAMTS-13, its main proteolytic enzyme. The aim of this study was to evaluate endothelial dysfunctions in patients with primary APS (PAPS), by examining correlation among the soluble endothelial marker, VWF, the enzyme ADAMTS-13, and FVIII protein. The relationship of these proteins and the presence of arterial and/or venous thrombosis, and presence of APL was also evaluated. This cross-sectional study involved 39 PAPS patients, with a median age of 43 years, who have been treated in the Outpatient Clinics, Department of Rheumatology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, and 39 healthy subjects blood donors from the Fundação Pró-Sangue Hemocentro de São Paulo, matched for sex and age with patients. Levels of APL (ACL and a-beta2GPI), concentration and activities of VWF, ADAMTS-13, FVIII and PF4 proteins were measured with ELISA. LA was detected with coagulation assays according to updated guidelines from the International Society on Thrombosis and Haemostasis, and FVIII activity was measured by chromogenic method. Analysis of VWF subunits was performed by Western immunoblotting. The results were evaluated according to:1- PAPS patients and controls, and2- PAPS patients grouped in relation to type of event and the type of APL. Patients showed higher VWF antigen concentration (74±6 x 69±11 IU/dL, p=0.016), ADAMTS-13 (1.3±0.34 x 0.82±0.12 Ug/mL, p < 0.0001), FVIII (106±19 x 91 ± 15 IU/dL, p=0.0003), VWF binding to FVIII (144±17 x 134 ± 20%, p=0.082) and activity of FVIII (117±38 x 98±30%, p=0.0021) than controls. The PF4 was decreased in patients compared to controls (96±12 vs. 101±8 IU/mL, p=0.014). VWF antigen and activity correlated well (Pearson´s r =0.468; p=0.028) as well as ADAMTS-13(Pearson´s r=0.635; p=0.001) in patients with arterial thrombosis. However, in patients with venous thrombosis only ADAMTS-13 had a good correlation (Pearson´s r =0.492; p=0.045). When patients were analyzed by the type of aPL, no differences in the studied variables were observed. Patients with PAPS seem to present endothelial dysfunction. However, apparently there is an attempt to balance mechanism to prevent a new thrombus formation. The role of VWF and its relation with ADAMTS-13 in different diseases is still relatively unknown. However it has been considered as important in the pathogenesis of prothrombotic states such as those present in patients with APS
415

Alterações hemostáticas e clínicas em cirurgias de revascularização miocárdica com e sem circulação extracorpórea: estudo prospectivo randomizado / Hemostatic changes and clinical sequelae after on-pump compared with off-pump coronary artery bypass surgery: a prospective randomized study

Felipe da Silva Paulitsch 07 January 2010 (has links)
Introdução: a revascularização miocárdica (RM) sem circulação extracorpórea (CEC) tem sido associada a menores complicações quando comparadas à com CEC. Objetivos: determinar os efeitos da CEC em marcadores de hemostasia, fibrinólise, inflamação e correlacionar com eventos clínicos. Método: os pacientes foram incluídos de forma prospectiva e randomizada para cirurgia de RM com (n=41) ou sem CEC (n=51). As concentrações de proteína C reativa (PCR), fibrinogênio, dímero-D e inibidor do ativador do plasminogênio tipo 1 (PAI1) foram quantificadas antes e após (1 e 24 horas) a RM. As técnicas cirúrgicas e anestésicas foram padronizadas para ambos os grupos. Eventos clínicos foram avaliados durante a hospitalização inicial e após 1 ano de seguimento. Resultados: as concentrações de PAI1 e dímeros-d foram maiores quando comparados os valores pré-operatórios com os de 1 e 24 h, após a RM em ambos os grupos, porém as concentrações de PAI1 aumentadas estenderam-se por 24 h após a RM com CEC (p<0,01). A concentração de PCR teve um aumento de pequena magnitude imediatamente após a cirurgia em ambos os grupos e aumentou de modo similar 24h após a RM (p<0,01). A RM com CEC foi associada com maior perda sanguínea durante a cirurgia e mais sangramento pós-operatório (p<0,01). A incidência de todas as outras complicações foi similar nos dois grupos. Conclusão: a RM com CEC apresentou evidências bioquímicas de um estado pró-trombótico precoce após a cirurgia, porém, sem evidências no aumento no número de eventos trombóticos. O estado pró-trombótico pode ser consequência do circuito extracorpóreo, resposta compensatória ao sangramento, ou a ambos em pacientes submetidos à cirurgia com CEC. / Objective: To delineate the effects of extracorporeal bypass on biomarkers of hemostasis, fibrinolysis, and inflammation and clinical sequelae. Methods: Patients were assigned prospectively and randomly to either on-pump (n=41) or off-pump (n=51) coronary bypass surgery. The concentrations of C-reactive protein (CRP), fibrinogen, D-dimer, and plasminogen activator inhibitor type 1 (PAI-1) in blood were quantified before and after (1 hour and 24 hours) surgery. Similar surgical and anesthetic procedures were used for both groups. Clinical events were assessed during initial hospitalization and at the end of 1 year. Results: The concentrations of PAI-1 and d-dimer were greater compared with preoperative values 1 hour and 24 hours after surgery in both groups, but their concentrations increased to a greater extent 24 hours after surgery in the on-pump group (p<0.01). The concentration of CRP did not change appreciably immediately after surgery in either group but increased in a parallel fashion 24 hours after either on-pump or off-pump surgery (p<0.01). Bypass surgery in the on-pump group was associated with greater blood loss during surgery and more bleeding after surgery (p0.01). The incidence of all other complications was similar in the 2 groups. Conclusion: On-pump surgery was associated with biochemical evidence of a pro-thrombotic state early after surgery but no greater incidence of thrombotic events. The pro-thrombotic state may have been a consequence of extracorporeal bypass, compensation in response to more bleeding, or both in patients undergoing on-pump surgery.
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Polydopamine-mediated long-term elution of the direct thrombin inhibitor bivalirudin from TiO₂ nanotubes for improved vascular biocompatibility

Yang, Zhilu, Zhong, Si, Yang, Ying, Maitz, Manfred F., Li, Xiangyang, Tu, Qiufen, Qi, Pengkai, Zhang, Heng, Qiu, Hua, Wan, Jin, Huang, Nan 07 January 2020 (has links)
Thrombosis and restenosis are two major complications associated with current commercial vascular stents. In situ regeneration of a healthy endothelium has been recognized as a promising strategy to address these issues. Numerous strategies have been explored for this goal. However, in most of the cases, they only focused on enhancing endothelial cell growth, ignoring antithrombotic requirements and the competition between smooth muscle cells (SMCs) and endothelial cells (ECs) for their growth. This resulted in non-satisfying clinical results. In this study, we created a multifunctional surface that meets the need of antithrombosis and re-endothelialization. A nanotubular titanium oxide (TiO₂) system has been developed, which elutes the direct thrombin inhibitor, bivalirudin (BVLD); moreover, polydopamine (PDAM) is used to tailor the surface functionality of TiO₂ nanotubes (NTs) for controlling the elution of BVLD. PDAM-functionalized TiO₂ NTs controls the BVLD for more than two months. BVLD eluted from NTs was bioactive and showed a substantial inhibitory effect on thrombin bioactivity, platelet adhesion and activation. In addition, the BVLD-eluting nanotubular TiO₂ system has high selectivity to enhance human umbilical vein endothelial cell (HUVEC) growth, while it inhibits human umbilical artery smooth muscle cell (HUASMC) proliferation. Our design strategy for the BVLD-eluting nanotubular TiO₂ system creates a favorable microenvironment for durable thromboresistance and the promotion of reendothelialization, and thus it is suitable for the long-term treatment of cardiovascular diseases.
417

Direct correlation of electrochemical behaviors with anti-thrombogenicity of semiconducting titanium oxide films

Wan, Guojiang, Lv, Bo, Jin, Guoshou, Maitz, Manfred F., Zhou, Jianzhang, Huang, Nan 11 October 2019 (has links)
Biomaterials-associated thrombosis is dependent critically upon electrochemical response of fibrinogen on material surface. The relationship between the response and anti-thrombogenicity of biomaterials is not well-established. Titanium oxide appears to have good anti-thrombogenicity and little is known about its underlying essential chemistry. We correlate their anti-thrombogenicity directly to electrochemical behaviors in fibrinogen containing buffer solution. High degree of inherent n-type doping was noted to contribute the impedance preventing charge transfer from fibrinogen into film (namely its activation) and consequently reduced degree of anti-thrombogenicity. The impedance was the result of high donor carrier density as well as negative flat band potential.
418

Contributors to Residual Cardiovascular Event Risk

Witkowski, Marco 26 May 2023 (has links)
No description available.
419

Cardiovascular Dysfunction in COVID-19: Association Between Endothelial Cell Injury and Lactate

Yang, Kun, Holt, Matthew, Fan, Min, Lam, Victor, Yang, Yong, Ha, Tuanzhu, Williams, David L., Li, Chuanfu, Wang, Xiaohui 01 January 2022 (has links)
Coronavirus disease 2019 (COVID-19), an infectious respiratory disease propagated by a new virus known as Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), has resulted in global healthcare crises. Emerging evidence from patients with COVID-19 suggests that endothelial cell damage plays a central role in COVID-19 pathogenesis and could be a major contributor to the severity and mortality of COVID-19. Like other infectious diseases, the pathogenesis of COVID-19 is closely associated with metabolic processes. Lactate, a potential biomarker in COVID-19, has recently been shown to mediate endothelial barrier dysfunction. In this review, we provide an overview of cardiovascular injuries and metabolic alterations caused by SARS-CoV-2 infection. We also propose that lactate plays a potential role in COVID-19-driven endothelial cell injury.
420

Enhancing Anticoagulation Monitoring and Therapy in Patients Undergoing Microvascular Reconstruction in Maxillofacial Surgery: A Prospective Observational Trial

Schröder, Tom A., Leonhardt, Henry, Haim, Dominik, Bräuer, Christian, Papadopoulos, Kiriaki K., Vicent, Oliver, Güldner, Andreas, Mirus, Martin, Schmidt, Jürgen, Held, Hanns C., Birkner, Thomas, Beyer-Westendorf, Jan, Lauer, Günter, Spieth, Peter M., Koch, Thea, Heubner, Lars 04 June 2024 (has links)
Background: In reconstructive surgery, loss of a microvascular free flap due to perfusion disorders, especially thrombosis, is a serious complication. In recent years, viscoelastic testing (VET) has become increasingly important in point-of-care (POC) anticoagulation monitoring. This paper describes a protocol for enhanced anticoagulation monitoring during maxillofacial flap surgery. Objective: The aim of the study will be to evaluate, in a controlled setting, the predictive value of POC devices for the type of flap perfusion disorders due to thrombosis or bleeding. VET, Platelet monitoring (PM) and standard laboratory tests (SLT) are comparatively examined. Methods/Design: This study is an investigator-initiated prospective trial in 100 patients undergoing maxillofacial surgery. Patients who undergo reconstructive surgery using microvascular-free flaps will be consecutively enrolled in the study. All patients provide blood samples for VET, PM and SLT at defined time points. The primary outcome is defined as free flap loss during the hospital stay. Statistical analyses will be performed using t-tests, including the Bonferroni adjustment for multiple comparisons. Discussion: This study will help clarify whether VET can improve individualized patient care in reconstruction surgery. A better understanding of coagulation in relation to flap perfusion disorders may allow real-time adaption of antithrombotic strategies and potentially prevent flap complications.

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