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Nové diagnostické a terapeutické aspekty zánětlivé kardiomyopatie / New diagnostic and therapeutic aspects of inflammatiory cardiomyopathyKuchynka, Petr January 2011 (has links)
Introduction: Inflammatory cardiomyopathy (DCMi) represents a non-familial form of dilated cardiomyopathy (DCM) and endomyocardial biopsy (EMB) is crucial for its diagnosis. Aims: To assess the prevalence of DCMi in patients with DCM of unclear origin, to evaluate the significance of serological tests for antibodies against infectious cardiotrophic agents and to analyze the effect of specific therapy guided by EMB results. Methods: EMB was performed in 56 subjects (mean age 52 ± 10 years) with DCM of unclear etiology and left ventricular (LV) ejection fraction (EF) < 40% with a history of heart failure less than 1 year. EMB samples were analyzed by immunohistochemistry, polymerase chain reaction (PCR) and electron microscopy. Results: Immunohistochemical examination revealed myocardial inflammation in 26 patients (46%), the PCR method detected genome of microbial agents in 32 patients (57%). Electron microscopy showed the presence of particles of microbial agents in 41 patients (73%). Serological blood tests found no IgM antibody positivity against any of the investigated microbial agents. Targeted antibiotic therapy in patients with evidence of Borrelia burgdorferi (Bb) genome in the EMB led to a reduction in LV size, improvement of LV EF and alleviate symptoms of heart failure. Conclusion: DCMi...
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Characterization by imaging and high-density electrophysiology of substrates and ventricular arrhythmias / Caracterisation par imagerie et électrophysiologie de haute densité de substrats et arythmies ventriculairesBerte, Benjamin 04 September 2015 (has links)
L'ablation par radiofréquence constitue un des traitements des tachycardies ventriculaires, en association avec les drogues anti-arythmiques et l’implantation d'un défibrillateur. L’objectif principal de cette thèse est de mieux comprendre le substrat arythmogène non seulement à l’aide d'imagerie cardiaque (IRM et scanner) de haute résolution et de cartographie de haute densité, en utilisant des cathéters multipolaires. Cela nous permettra d'analyser la relation structure-fonction. Nous avons étudié cette relation sur différents types de substrats (ICM, NICM, DAVD, et myocardites). Nous avons ainsi prouvé la supériorité de la cartographie de haute densité obtenue à partir de cathéters multipolaires, comparativement aux données recueillies par l’imagerie, dans l’identification de la cicatrice arythmogène et la détection des LAVA. La deuxième partie de cette thèse concerne l’étude du substrat arythmogène épicardique. Nous avons ainsi décrit la technique de cartographie par voie percutanée antérieure, puis démontré l'efficacité des procédures uniquement avec abord épicardique. La segmentation du nerf phrénique et des artères coronaires ont permis de diminuer le taux de complications théoriquement liés à cet abord. Nous avons poursuivi ce travail avec l’analyse des sites d'intérêt de l'ablation des TV: les LAVA. Après une description de la stratégie d’élimination des LAVA, nous avons tenté de trouver des prédicteurs permettant de localiser les sites de LAVA, à partir des données d'imagerie. Quand l'imagerie montre une cicatrice intraseptale ou intramurale, les LAVA ne peuvent pas être enregistrés avec la cartographie et des alternative techniques d'ablation sont nécessaires comme une ablation bipolaire, l'alcoolisation intra coronaire et l'ablation avec l'aiguille irriguée. Le dernier chapitre est une revue sur le futur de l'imagerie, de la cartographie et de l’ablation des tachycardies ventriculaires. Une meilleure compréhension du substrat arythmogène pourrait améliorer l'efficacité et la sécurité des ablations de tachycardie ventriculaire. / Radiofrequency (RF) catheter ablation is an effective treatment strategy for scar-related ventricular tachycardia (VT), resistant to anti-arrhythmic drugs and intracardiac defibrillator (ICD) placement. The goal of this thesis was to better understand and characterize the arrhythmogenic VT substrate in different cardiomyopathic processes: ischaemic cardiomyopathy (ICM), non-ischaemic cardiomyopathy (NICM), arrhythmogenic right ventricular cardiomyopathy (ARVC) and myocarditis. For this purpose, we combined high resolution imaging including different modalities and high resolution electrical mapping to better understand the structure-function relationship. We focused on multiple different aspects of VT ablation as outlined below. The first part of this thesis focuses on the role of multipolar mapping catheters and imaging to analyze their structural and functional relationship. We demonstrated superiority of high density mapping with multipolar mapping on conventional mapping in detection of scar, channels, local abnormal ventricular activity (LAVA) and sensitivity for near field signals. The second part of this thesis focuses on ablation of epicardial VT substrate. We demonstrated the efficacy and safety of epicardial only procedures in a highly selected population. We used imaging to have access to the exact anatomy of the heart, to image the substrate but also to increase the safety of ablation procedures by imaging the phrenic nerve and the coronary artery system. The third part of this thesis focuses on analysis of the mapping and ablation of potential targets for scar-related VT ablation. Within this context, we identified predictors of interesting ablation (LAVA) sites based on preprocedural imaging. We also analyzed the role of alternative strategies such as bipolar ablation, ethanol ablation and irrigated needle ablation to ablate intramural and intraseptal substrate, 18 often resistant ablation targets. Overall, we demonstrate that novel imaging, mapping and ablation techniques potentially improve the outcome of VT ablation.
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Nové diagnostické a terapeutické aspekty zánětlivé kardiomyopatie / New diagnostic and therapeutic aspects of inflammatiory cardiomyopathyKuchynka, Petr January 2011 (has links)
Introduction: Inflammatory cardiomyopathy (DCMi) represents a non-familial form of dilated cardiomyopathy (DCM) and endomyocardial biopsy (EMB) is crucial for its diagnosis. Aims: To assess the prevalence of DCMi in patients with DCM of unclear origin, to evaluate the significance of serological tests for antibodies against infectious cardiotrophic agents and to analyze the effect of specific therapy guided by EMB results. Methods: EMB was performed in 56 subjects (mean age 52 ± 10 years) with DCM of unclear etiology and left ventricular (LV) ejection fraction (EF) < 40% with a history of heart failure less than 1 year. EMB samples were analyzed by immunohistochemistry, polymerase chain reaction (PCR) and electron microscopy. Results: Immunohistochemical examination revealed myocardial inflammation in 26 patients (46%), the PCR method detected genome of microbial agents in 32 patients (57%). Electron microscopy showed the presence of particles of microbial agents in 41 patients (73%). Serological blood tests found no IgM antibody positivity against any of the investigated microbial agents. Targeted antibiotic therapy in patients with evidence of Borrelia burgdorferi (Bb) genome in the EMB led to a reduction in LV size, improvement of LV EF and alleviate symptoms of heart failure. Conclusion: DCMi...
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Análise proteômica no miocárdio de pacientes com cardiomiopatia chagásica crônica: alterações no metabolismo energético cardíaco / Proteomic Analysis in the myocardium from patients with chronic Chagas disease cardiomyopathy: alterations in the cardiac energy metabolismTeixeira, Priscila Camillo 22 January 2010 (has links)
A patogênese da Cardiomiopatia Chagásica Crônica (CCC) ainda é assunto de intenso debate. A CCC apresenta intenso infiltrado inflamatório no tecido cardíaco, onde os linfócitos T infiltrantes produzem citocinas inflamatórias, como IFN-gama e TNF-alfa. Adicionalmente, pacientes com CCC apresentam um pior prognóstico quando comparados aos portadores de outras cardiomiopatias de etiologia não inflamatória, como a cardiomiopatia dilatada idiopática (CDI) e a cardiomiopatia isquêmica (CI), sugerindo que mecanismos inflamatórios participam da patogênese e evolução da doença. Além disso, evidências anteriores de nosso grupo indicaram alterações do metabolismo energético na CCC. Neste trabalho, comparamos a expressão protéicado miocárdio de pacientes com CCC, CDI e CI e indivíduos sem cardiomiopatias, com foco em proteínas relacionadas ao metabolismo energético celular. Para a identificação do perfil de expressão protéica no miocárdio de pacientes com CCC, utilizamos a técnica de separação por eletroforese bidimensional, e a identificação das proteínas foi feita por espectrometria de massa. A maioria dos spots identificados corresponde a proteínas estruturais ou proteínas do metabolismo, principalmente do metabolismo energético. Foram identificadas também proteínas envolvidas na apoptose, em processos imunes e de resposta ao estresse. A análise da expressão protéica diferencial, utilizando marcação fluorescente, nos permitiu analisar o padrão de expressão das proteínas diferencialmente expressas no miocárdio de pacientes com CCC, CDI e CI e de indivíduos sem cardiomiopatias, dentro de um total de 683 spots e 230 proteínas distintas identificadas. Observamos que o padrão de expressão protéica do miocárdio de pacientes com CCC é o mais distinto em relação ao padrão de expressão protéica presente no miocárdio de indivíduos sem cardiomiopatias; e que o padrão de expressão das proteínas presentes no miocárdio de pacientes com CI é o que mais se assemelha ao padrão de indivíduos sem cardiomiopatias. Encontramos várias proteínas com expressão alterada em amostras de pacientes com CCC, CDI e CI em comparação com amostras de indivíduos sem cardiomiopatias, as quais desempenham papéis fundamentais em processos envolvidos na patologia de doenças cardiovasculares como apoptose (ex. catepsina D e Akt2), estresse oxidativo (ex. catalase), estresse do retículo endoplasmático (ex: proteína dissulfito isomerase), remodelamento cardíaco (ex: gelsolina) e outros. A análise individual das proteínas diferencialmente expressas entre os grupos de cardiomiopatia também mostrou que o miocárdio de pacientes com CCC apresenta expressão reduzida de várias proteínas mitocondriais associadas ao metabolismo energético nas vias da glicólise, ciclo de Krebs, beta-oxidação, na fosforilação oxidativa, e do complexo creatina-quinase - em comparação com miocárdio de indivíduos sem cardiomiopatias. Embora algumas dessas alterações tenham sido compartilhadas com a CDI, e em menor grau com a CI, observamos que os pacientes CCC apresentam o maior comprometimento do sistema creatina quinase, incluindo sua atividade enzimática. Também observamos que componentes do complexo enzimático da ATP sintase encontram-se reduzidos em amostras de pacientes com CCC em comparação aos indivíduos sem cardiomiopatia. Observamos também aumento de expressão de proteínas de stress incluindo estresse oxidativo, associadas à apoptose, e ao sistema imune no miocárdio de pacientes CCC, além da subunidade do imunoproteasomo e de proteínas associadas à degradação protéica. Em conjunto, nossos resultados sugerem que a diminuição de expressão das proteínas essenciais à geração de ATP, o aumento da expressão de proteínas associadas à apoptose e de proteínas do sistema imune no miocárdio de pacientes com CCC em comparação aos pacientes CI e CDI podem estar relacionados à pior evolução da CCC. Nossa análise de padrões de expressão protéica identificou conjuntos de proteínas capazes de discriminar as amostras de miocárdio por etiologia. Isto poderá auxiliar no diagnóstico e na descoberta de biomarcadores periféricos de cardiomiopatias, bem como ajudar na elucidação dos mecanismos de desenvolvimento da doença e de alterações estruturais / moleculares do miocárdio em resposta à inflamação crônica. / The pathogenesis of Chagas disease cardiomyopathy (CCC) is still controversial. CCC is characterized by an intense cardiac inflammatory infiltrate; infiltrating T lymphocytes produce inflammatory cytokines such as IFN-gamma and TNF-alpha. Patients afflicted by CCC display a worse prognosis when compared to patients afflicted by non-inflammatory cardiomyopathies such as idiopathic dilated cardiomyopathy (IDC) and ischemic cardiomyopathy (IC), suggesting that inflammatory mechanisms play a role in the pathogenesis and progression of the disease. In addition, previous evidence from our group suggested the presence of energy metabolism changes in CCC. In the present work, we compared the protein expression profile of the myocardium of patients with CCC, IDC, IC, and noncardiomyopathic subjects, with focus on energetic metabolism-related proteins. We used bidimensional electrophoresis to analyze the protein expression profile in the myocardium of patients afflicted by CCC, and proteins were identified by mass spectrometry. The majority of spots were identified as structural proteins or metabolism proteins, especially of energy metabolism. We were also able to identify apoptosis-, immune system- and stress response-related proteins. Using fluorescent labeling, we analyzed the differential expression profile in the myocardium of CCC, IDC and IC patients, from a total of 683 spots and 230 distinct proteins identified. We observed that the protein expression profile of CCC patients is the most distinct when compared to non-cardiomyopathic subjects. On the other hand, the protein expression profile of IC patients is similar, at some extent, to the expression profile of non-cardiomyopathic patients. We also found altered expression of proteins related to apoptosis (e.g. cathepsin D and Akt2), oxidative stress (e.g. catalase), endoplasmic reticulum stress (e.g. disulfilte isomerase protein), cardiac remodeling (e.g. gelsolin) among CCC, IDC and IC patients when compared to noncardiomyopathic patients. Most of these proteins, if not all, play fundamental roles in the pathogenesis of cardiovascular diseases. We also showed that the myocardium of patients afflicted by CCC display altered expression of several mitochondrial proteins associated to energy metabolism in the glycolysis, Krebs cycle, betaoxidation, oxidative phosphorylation, and creatine kinase complex when compared to non-cardiomyopathic subjects. Although some of these changes were shared with IDC samples, and, to a lesser extent, with CI samples, Western blot analysis demonstrated that CCC samples showed the most extreme reduction in protein expression of the creatine kinase system, including its enzymatic activity. We also observed with Western blot analysis that proteins from the ATP synthase complex (subunits alpha and beta) showed decreased expression in myocardium of CCC patients when compared to non-cardiomyopathic subjects and when compared to IC patients. We also observed an increase in the protein expression of stress proteins, including those involved in the oxidative stress response, those associated to apoptosis, and immune system proteins in CCC myocardium, along with increased expression of the immunoproteasome subunit and proteins associated to protein degradation. Taken together, our results suggest that diminished expression of proteins fundamental for ATP generation, increased expression of apoptosisassociated proteins and immune system proteins in the myocardium of CCC patients when compared to IC and IDC patients may be associated to CCC progression. The analysis of the protein expression profile has identified groups of proteins whose expression pattern is able to discriminate the myocardium samples by etiology. This may help to find novel peripheral biomarkers of CCC and other cardiomyopathies, as well as in the understanding of mechanisms of disease progression and structural/molecular alterations of the inflamed myocardium.
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Análise proteômica no miocárdio de pacientes com cardiomiopatia chagásica crônica: alterações no metabolismo energético cardíaco / Proteomic Analysis in the myocardium from patients with chronic Chagas disease cardiomyopathy: alterations in the cardiac energy metabolismPriscila Camillo Teixeira 22 January 2010 (has links)
A patogênese da Cardiomiopatia Chagásica Crônica (CCC) ainda é assunto de intenso debate. A CCC apresenta intenso infiltrado inflamatório no tecido cardíaco, onde os linfócitos T infiltrantes produzem citocinas inflamatórias, como IFN-gama e TNF-alfa. Adicionalmente, pacientes com CCC apresentam um pior prognóstico quando comparados aos portadores de outras cardiomiopatias de etiologia não inflamatória, como a cardiomiopatia dilatada idiopática (CDI) e a cardiomiopatia isquêmica (CI), sugerindo que mecanismos inflamatórios participam da patogênese e evolução da doença. Além disso, evidências anteriores de nosso grupo indicaram alterações do metabolismo energético na CCC. Neste trabalho, comparamos a expressão protéicado miocárdio de pacientes com CCC, CDI e CI e indivíduos sem cardiomiopatias, com foco em proteínas relacionadas ao metabolismo energético celular. Para a identificação do perfil de expressão protéica no miocárdio de pacientes com CCC, utilizamos a técnica de separação por eletroforese bidimensional, e a identificação das proteínas foi feita por espectrometria de massa. A maioria dos spots identificados corresponde a proteínas estruturais ou proteínas do metabolismo, principalmente do metabolismo energético. Foram identificadas também proteínas envolvidas na apoptose, em processos imunes e de resposta ao estresse. A análise da expressão protéica diferencial, utilizando marcação fluorescente, nos permitiu analisar o padrão de expressão das proteínas diferencialmente expressas no miocárdio de pacientes com CCC, CDI e CI e de indivíduos sem cardiomiopatias, dentro de um total de 683 spots e 230 proteínas distintas identificadas. Observamos que o padrão de expressão protéica do miocárdio de pacientes com CCC é o mais distinto em relação ao padrão de expressão protéica presente no miocárdio de indivíduos sem cardiomiopatias; e que o padrão de expressão das proteínas presentes no miocárdio de pacientes com CI é o que mais se assemelha ao padrão de indivíduos sem cardiomiopatias. Encontramos várias proteínas com expressão alterada em amostras de pacientes com CCC, CDI e CI em comparação com amostras de indivíduos sem cardiomiopatias, as quais desempenham papéis fundamentais em processos envolvidos na patologia de doenças cardiovasculares como apoptose (ex. catepsina D e Akt2), estresse oxidativo (ex. catalase), estresse do retículo endoplasmático (ex: proteína dissulfito isomerase), remodelamento cardíaco (ex: gelsolina) e outros. A análise individual das proteínas diferencialmente expressas entre os grupos de cardiomiopatia também mostrou que o miocárdio de pacientes com CCC apresenta expressão reduzida de várias proteínas mitocondriais associadas ao metabolismo energético nas vias da glicólise, ciclo de Krebs, beta-oxidação, na fosforilação oxidativa, e do complexo creatina-quinase - em comparação com miocárdio de indivíduos sem cardiomiopatias. Embora algumas dessas alterações tenham sido compartilhadas com a CDI, e em menor grau com a CI, observamos que os pacientes CCC apresentam o maior comprometimento do sistema creatina quinase, incluindo sua atividade enzimática. Também observamos que componentes do complexo enzimático da ATP sintase encontram-se reduzidos em amostras de pacientes com CCC em comparação aos indivíduos sem cardiomiopatia. Observamos também aumento de expressão de proteínas de stress incluindo estresse oxidativo, associadas à apoptose, e ao sistema imune no miocárdio de pacientes CCC, além da subunidade do imunoproteasomo e de proteínas associadas à degradação protéica. Em conjunto, nossos resultados sugerem que a diminuição de expressão das proteínas essenciais à geração de ATP, o aumento da expressão de proteínas associadas à apoptose e de proteínas do sistema imune no miocárdio de pacientes com CCC em comparação aos pacientes CI e CDI podem estar relacionados à pior evolução da CCC. Nossa análise de padrões de expressão protéica identificou conjuntos de proteínas capazes de discriminar as amostras de miocárdio por etiologia. Isto poderá auxiliar no diagnóstico e na descoberta de biomarcadores periféricos de cardiomiopatias, bem como ajudar na elucidação dos mecanismos de desenvolvimento da doença e de alterações estruturais / moleculares do miocárdio em resposta à inflamação crônica. / The pathogenesis of Chagas disease cardiomyopathy (CCC) is still controversial. CCC is characterized by an intense cardiac inflammatory infiltrate; infiltrating T lymphocytes produce inflammatory cytokines such as IFN-gamma and TNF-alpha. Patients afflicted by CCC display a worse prognosis when compared to patients afflicted by non-inflammatory cardiomyopathies such as idiopathic dilated cardiomyopathy (IDC) and ischemic cardiomyopathy (IC), suggesting that inflammatory mechanisms play a role in the pathogenesis and progression of the disease. In addition, previous evidence from our group suggested the presence of energy metabolism changes in CCC. In the present work, we compared the protein expression profile of the myocardium of patients with CCC, IDC, IC, and noncardiomyopathic subjects, with focus on energetic metabolism-related proteins. We used bidimensional electrophoresis to analyze the protein expression profile in the myocardium of patients afflicted by CCC, and proteins were identified by mass spectrometry. The majority of spots were identified as structural proteins or metabolism proteins, especially of energy metabolism. We were also able to identify apoptosis-, immune system- and stress response-related proteins. Using fluorescent labeling, we analyzed the differential expression profile in the myocardium of CCC, IDC and IC patients, from a total of 683 spots and 230 distinct proteins identified. We observed that the protein expression profile of CCC patients is the most distinct when compared to non-cardiomyopathic subjects. On the other hand, the protein expression profile of IC patients is similar, at some extent, to the expression profile of non-cardiomyopathic patients. We also found altered expression of proteins related to apoptosis (e.g. cathepsin D and Akt2), oxidative stress (e.g. catalase), endoplasmic reticulum stress (e.g. disulfilte isomerase protein), cardiac remodeling (e.g. gelsolin) among CCC, IDC and IC patients when compared to noncardiomyopathic patients. Most of these proteins, if not all, play fundamental roles in the pathogenesis of cardiovascular diseases. We also showed that the myocardium of patients afflicted by CCC display altered expression of several mitochondrial proteins associated to energy metabolism in the glycolysis, Krebs cycle, betaoxidation, oxidative phosphorylation, and creatine kinase complex when compared to non-cardiomyopathic subjects. Although some of these changes were shared with IDC samples, and, to a lesser extent, with CI samples, Western blot analysis demonstrated that CCC samples showed the most extreme reduction in protein expression of the creatine kinase system, including its enzymatic activity. We also observed with Western blot analysis that proteins from the ATP synthase complex (subunits alpha and beta) showed decreased expression in myocardium of CCC patients when compared to non-cardiomyopathic subjects and when compared to IC patients. We also observed an increase in the protein expression of stress proteins, including those involved in the oxidative stress response, those associated to apoptosis, and immune system proteins in CCC myocardium, along with increased expression of the immunoproteasome subunit and proteins associated to protein degradation. Taken together, our results suggest that diminished expression of proteins fundamental for ATP generation, increased expression of apoptosisassociated proteins and immune system proteins in the myocardium of CCC patients when compared to IC and IDC patients may be associated to CCC progression. The analysis of the protein expression profile has identified groups of proteins whose expression pattern is able to discriminate the myocardium samples by etiology. This may help to find novel peripheral biomarkers of CCC and other cardiomyopathies, as well as in the understanding of mechanisms of disease progression and structural/molecular alterations of the inflamed myocardium.
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COVID-19 in German Competitive Sports: Protocol for a Prospective Multicenter Cohort Study (CoSmo-S)Niess, Andreas Michael, Widmann, Manuel, Gaidai, Roman, Gölz, Christian, Schubert, Isabel, Castillo, Katty, Sachs, Jan Philipp, Bizjak, Daniel, Vollrath, Shirin, Wimbauer, Fritz, Vogel, Azin, Keller, Karsten, Burgstahler, Christof, Quermann, Anne, Kerling, Arno, Schneider, Gerald, Zacher, Jonas, Diebold, Katharina, Grummt, Maximilian, Beckendorf, Claudia, Buitenhuis, Johannes, Egger, Florian, Venhorst, Andreas, Morath, Oliver, Barsch, Friedrich, Mellwig, Klaus-Peter, Oesterschlink, Julian, Wüstenfeld, Jan, Predel, Hans-Georg, Deibert, Peter, Friedmann-Bette, Birgit, Mayer, Frank, Hirschmüller, Anja, Halle, Martin, Steinacker, Jürgen Michael, Wolfarth, Bernd, Meyer, Tim, Böttinger, Erwin, Flechtner-Mors, Marion, Bloch, Wilhelm, Haller, Bernhard, Roecker, Kai, Reinsberger, Claus 25 January 2024 (has links)
Objective: It is unclear whether and to what extent COVID-19 infection poses health risks
and a chronic impairment of performance in athletes. Identification of individual health risk
is an important decision-making basis for managing the pandemic risk of infection with
SARS-CoV-2 in sports and return to play (RTP).
Methods: This study aims 1) to analyze the longitudinal rate of seroprevalence of SARSCoV-
2 in German athletes, 2) to assess health-related consequences in athletes infected
with SARS-CoV-2, and 3) to reveal effects of the COVID-19 pandemic in general and of a
cleared SARS-CoV-2 infection on exercise performance. CoSmo-S is a prospective
observational multicenter study establishing two cohorts: 1) athletes diagnosed positive
for COVID-19 (cohort 1) and 2) federal squad athletes who perform their annual sports
medical preparticipation screening (cohort 2). Comprehensive diagnostics including physical examination, laboratory blood analyses and blood biobanking, resting and
exercise electrocardiogram (ECG), echocardiography, spirometry and exercise testing
added by questionnaires are conducted at baseline and follow-up.
Results and Conclusion: We expect that the results obtained, will allow us to formulate
recommendations regarding RTP on a more evidence-based level.
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The impact of immunoproteasomes in murine CVB3-associated myocarditisOpitz, Elisa 02 May 2013 (has links)
Das Proteasom ist ein multikatalytischer, ATP-abhängiger Enzymkomplex, der kurzlebige und regulatorische Proteine in der Zelle abbaut. Im Rahmen der Proteinqualitätskontrolle werden durch das Proteasom auch fehlerhaft synthetisierte bzw. falsch gefaltete oder chemisch geschädigte Proteine degradiert. Zellen hämatopoetischen Ursprungs exprimieren sogenannte Immunoproteasomen, die durch drei alternative katalytische Untereinheiten (LMP2, MECL-1 und LMP7) charakterisiert sind. Unter dem Einfluss von Interferonen kommt es auch in nicht-hämatopoetischen Zellen zur de novo Assemblierung von IP. Sie weisen im Vergleich zu Standardproteasomen einen erhöhten Substratumsatz sowie veränderte Schnittpräferenzen auf. Dadurch können Standard- und Immunoproteasomen verschiedene MHC Klasse I-restringierte antigene Peptide generieren. Die vorliegende Arbeit untersucht die Relevanz der LMP2- bzw. der LMP7- Untereinheit im Rahmen der Coxsackievirus B3 Myokarditis. LMP7-/- Mäuse zeigen eine suffiziente CD8+ T Zell Antwort, die zur vollständigen Viruselimination nach der akuten Entzündungsphase beiträgt. Die reguläre Expression pro-inflammatorischer Zytokine und antiviraler Signalwege sowie CVB3-spezifischer IgG-Antikörper spricht gegen eine spezielle Funktion von IP bei der Induktion einer effektiven Immunantwort in diesem Modell. Es konnte jedoch gezeigt werden, dass der verminderte Einbau aller IP-Untereinheiten in LMP7-defizienten Mäusen mit einer schweren Inflammation und Myokardschädigung einhergeht. Der verringerte Substratumsatz führt zur Akkumulation von polyubiquitinylierten, oxidativ geschädigten Proteinen sowie zur verstärkten Apoptose IP-defizienter Kardiomyozyten und inflammatorischer Zellen. / The standard proteasome is the major ATP-dependent multi-catalytic protein complex that is important for the proteolytic processing of short-lived and regulatory proteins. It also degrades exogenous or improperly synthesized, misfolded, and damaged proteins. Cells of hematopoietic origin predominantly express an alternative variant - the immunoproteasome, which is characterized by three specific catalytically active subunits (LMP2, MECL-1 and LMP7). In non-immune cells, these immunosubunits are also induced and incorporated into newly assembling IPs upon exposure to interferons. As compared to standard proteasomes, IPs display altered cleavage site preferences, resulting in the generation of a different spectrum of antigenic peptides for MHC class I presentation. The present thesis investigates the impact of LMP2- and LMP7 within the context of viral heart disease, making use of the well-established murine model of coxsackievirus B3 infection. LMP7-deficient mice demonstrate a potent CD8+ T cell capacity to control CVB3 infection, resulting in viral clearance after the acute stage of disease. The expression of pro-inflammatory cytokines, innate antiviral mediators, and CVB3-specific IgG antibodies argue against a specific role of IPs in the induction of an effective immune response against CVB3 infection. However, the impaired incorporation of all three immunosubunits in LMP7-deficient hearts coincides with severe inflammation and myocardial tissue damage. Exposure to IFN-γ gives rise to prolonged accumulation of oxidant-damaged, poly-ubiquitylated proteins in IP-deficient cardiomyocytes and inflammatory cells. Along with the restricted degradation of toxic protein aggregates, inflammatory cells and the adjacent myocardium are prone to increased apoptotic cell death.
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Avaliação da inflamação miocárdica na doença de Chagas por ressonância magnética cardiovascular / Detection of myocardial inflammation in Chagas\' heart disease by cardiac magnetic resonanceTorreão, Jorge Andion 12 March 2015 (has links)
INTRODUÇÃO: A cardiopatia chagásica (CC) é um importante problema de saúde pública na América do Sul e a patogênese desta doença ainda não é totalmente compreendida, mas a inflamação e a fibrose miocárdica participam de forma central no processo crônico e progressivo de dano miocárdico. Trabalho prévio de nosso grupo demonstrou a capacidade da Ressonância Magnética Cardiovascular (RMC) de identificar precisamente a fibrose miocárdica em pacientes com Doença de Chagas. A RMC demonstrou ser eficaz para avaliar edema miocárdico, como marcador de inflamação, e ser altamente sensível para a detecção de trombos intracavitários, especialmente no ventrículo esquerdo, e em outras patologias, como miocardites e infartos. A avaliação de edema miocárdio pela RMC em pacientes com CC não foi ainda avaliada na literatura. Nosso objetivo foi investigar a presença de edema e fibrose miocárdica nas três formas clínicas da CC, o que julgamos ser de potencial valor diagnóstico e prognóstico. MÉTODOS: Cinquenta e quatro pacientes com doença de chagas foram analisados: 16 pacientes com a forma indeterminada (FI), 17 pacientes com CC-SD e 21 pacientes com CC-CD. Todos os pacientes foram submetidos a exame de RMC em equipamento de 1,5 T, utilizando a sequência de realce tardio do miocárdio (RTM), a sequência de edema miocárdico (Spin-eco ponderado em T2) e a sequência de realce global precoce ponderado T1 pós-contraste, para identificar fibrose, edema e hiperemia miocárdicos, respectivamente. RESULTADOS: A fibrose miocárdica foi encontrada em 39 indivíduos, 72,2% de toda a amostra. A fibrose miocárdica foi detectada em 2 pacientes (12,5%) na forma indeterminada, com uma massa de fibrose média de 0,85 ± 2,47g. Os pacientes da forma CC-SD em sua quase totalidade - 16 pacientes (94,1%) - apresentaram fibrose, com uma massa média de 13,0 ± 10,8g. Todos os pacientes com a forma CC-CD apresentaram fibrose miocárdica (21 pacientes) e adicionalmente detinham a maior massa de fibrose média, 25 ± 11,9g. O edema miocárdico foi encontrado em 40 indivíduos, 74,0% de toda a amostra. A extensão do edema miocárdico foi analisada pelo número de segmentos comprometidos. Foram identificados 3 pacientes (18,8%) da forma indeterminada com critérios positivos para edema miocárdio, determinando uma média de 0,31 ± 0,87 segmentos. A forma CC-SD obteve a presença de edema em 16 indivíduos (94,1%) distribuídos em uma média de 3,24 ± 2,3 segmentos. Todos os pacientes da forma CC-CD apresentaram edema miocárdico pela RMC, em uma média 3,67 ± 1,82 segmentos (p < 0,001). Houve correlação significativa entre a quantidade de fibrose miocárdica e edema miocárdico com a gravidade das formas clínicas (p < 0,001), classe funcional (p < 0,001), fração de ejeção do VE (p < 0,001) e volume diastólico do VE(p < 0,001). CONCLUSÃO: Fibrose e inflamação miocárdica foram detectadas pela ressonância magnética cardíaca em pacientes portadores de cardiopatia chagásica em todas as fases crônicas da doença, inclusive naqueles pacientes sem cardiopatia ou com cardiopatia sem disfunção ventricular. A quantidade de fibrose e edema miocárdico apresenta correlação com a gravidade da forma clínica, classe funcional, fração de ejeção do VE e dilatação do VE / BACKGROUND AND PURPOSE: Chagas\' heart disease (CHD) is a major public health problem in South America, and the pathogenesis of this disease is not yet fully understood, but inflammation and myocardial fibrosis seem to play a central role in the process of chronic and progressive myocardial damage. Previous descriptions from our group demonstrated the ability of Cardiovascular Magnetic Resonance (CMR) accurately identify myocardial fibrosis in patients with CHD. CMR shown to be effective for assessing myocardial edema, a marker of inflammation, and is highly sensitive for the detection of thrombi, especially in the left ventricle in other pathologies such as myocarditis and myocardial infarct. The assessment of myocardial edema by CMR in patients with CHD has not been evaluated. We believe to be of potential diagnostic and prognostic value to investigate the presence of myocardial edema and fibrosis in patients in the three clinical forms of this disease. METHODS: Fifty-four patients with Chagas\' disease were analyzed: 16 patients with the indeterminate phase (IF), 17 patients with the cardiac form without left ventricular systolic dysfunction (CFWO), and 21 patients with the cardiac form with left ventricular systolic dysfunctional form (CFSD). All patients underwent 1.5-T cardiac magnetic resonance (CMR) using the myocardial delayed enhancement sequence (MDE), T2-weighted sequence and the T1 weighted global enhancement after contrast sequence, to identify fibrosis, edema and hyperemia, respectively. RESULTS: Myocardial fibrosis was found in 39 subjects, 72.2% of the entire sample. Myocardial fibrosis was detected in 2 patients (12.5%) with the indeterminate form, representing an average mass of fibrosis of 0.85 ± 2.47 g. Patients with the CFWO almost entirely, 16 patients (94.1%) showed fibrosis, representing an average mass of fibrosis of 13.0 ± 10.8 g. All patients with the CFSD had myocardial fibrosis (21 patients) additionally had greater average mass of fibrosis 11.9 ± 25g. The myocardial edema was found in 40 subjects, 74.0% of the entire sample. The extent of myocardial edema was determined by the number of segments affected. We identified three patients (18.8%) from the indeterminate form with myocardial edema, an average of 0.31 ± 0.87. The CFWO presented a high presence of edema in 16 individuals (94.1%) distributed in an average of 3.24 ± 2.3 segments. All patients with the CFSD presented myocardial edema, an average of 3.67 ± 1.82 segments. (p < 0.001). There was significant correlation between the amount of myocardial fibrosis and myocardial edema with the severity of the clinical forms ( p < 0.001 ), functional class ( p < 0.001 ), LV ejection fraction ( p < 0.001 ) and left ventricular diastolic volume ( p < 0.001). CONCLUSION: Myocardial fibrosis and inflammation were detected by cardiac magnetic resonance imaging in patients with Chagas\' disease in all stages of chronic disease, including those patients without heart disease or cardiomyopathy without ventricular dysfunction. The amount of fibrosis and myocardial edema correlates with the severity of the clinical, functional class, LV ejection fraction and LV dilation
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Análise das metaloproteinases de matriz e seus inibidores no tecido cardíaco de pacientes com cardiomiopatia chagásica crônica / Analysis of matrix metalloproteinases and their inhibitors in heart tissue of chronic Chagas disease cardiomyopathy patientsBaron, Monique Andrade 06 July 2015 (has links)
A Cardiomiopatia Chagásica Crônica (CCC) é uma cardiopatia dilatada inflamatória caracterizada por remodelamento cardíaco, uma miocardite rica em células T e macrófagos, hipertrofia e fibrose. Essa acomete 30% dos pacientes infectados com Trypanossoma cruzi (T. cruzi). Os pacientes com CCC apresentam uma pior sobrevida e prognóstico quando comparados com pacientes portadores de cardiomiopatia de etiologia não inflamatória, como a cardiomiopatia dilatada idiopática (CDI). No processo de remodelamento cardíaco, ocorre uma reestruturação da matriz extracelular (MEC), mediada em grande parte por proteínas como as enzimas proteolíticas, metaloproteinases da matriz (MMPs) e seus inibidores específicos (TIMPs), sendo que a alteração e/ou atividade de algumas dessas enzimas em particular está relacionado com as doenças cardiovasculares. Dentro deste contexto, a hipótese deste trabalho é a de que o perfil da expressão e atividade das MMPs e de seus inibidores TIMPs na CCC será distinto do encontrado na CDI. Foi avaliado por qRT-PCR a expressão gênica e por \"Western blotting\" a expressão proteica das MMPs: -1, -2, -3, -8, -9, -12-13 e EMMPRIN e dos seguintes inibidores TIMPs: -1, -2, -3, -4 e RECK e atividade da MMP-2 e -9 por zimografia, em amostras de miocárdio (ventrículo esquerdo) de pacientes com CCC, pacientes com CDI e doadores de órgãos, obtidos durante o procedimento de transplante. Embora algumas das alterações da expressão das MMPs, TIMPs, e RECK tenham sido compartilhadas com a CDI, observamos que os pacientes com CCC apresentam o aumento da atividade da MMP-2 e MMP-9 e aumento exclusivo da proteína MMP-9. Analisamos através da razão entre a atividade da MMP-2 e MMP-9 com a expressão proteica dos inibidores TIMPs e RECK, observamos o aumento da atividade da MMP-2 e MMP-9 e a diminuição dos TIMPs: -1, -2, -3 e -4 e TIMPs -1, -2 e -3, respectivamente em pacientes com CCC, ocasionando um desequilíbrio entre sua ativação e inibição o que contribui com o remodelamento do miocárdio. Também foi avaliado a fração de colágeno intersticial por Picrosirius Red, observamos que o aumento de colágeno em pacientes com CCC e CDI, o que indica que o aumento da atividade da MMP-2 e MMP-9 está modulando a síntese, conformação e organização do colágeno, contribuindo com a fibrose em pacientes com CCC. Com objetivo de verificar se estas MMPs e seus inibidores estariam sob-regulação pós-transcricional, realizamos análise in silico e identificamos 8 microRNAs (miR): miR-21, miR-29- 5p, miR-146a-5p, miR-155-5p, miR-188-5p, miR-214-3p, miR-491-5p e miR885-5p e analisamos suas expressões por qRT-PCR, mas não observamos correlação com as MMPs e seus inibidores, sugerindo que estas proteínas não estão sob regulação pós-transcricional pelos miRs analisados. Em conjunto, nossos resultados sugerem que a expressão diferencial de MMPs e seus inibidores TIMPs estudados contribuem com a fibrose, remodelamento do miocárdio e disfunção cardíaca, observado em pacientes com CCC. Desta forma, este trabalho pode ajudar na elucidação dos mecanismos de desenvolvimento da patogênese da doença de Chagas / Chronic Chagas Cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy characterized by cardiac remodeling, a myocarditis rich in T cells and macrophages, hypertrophy and fibrosis. This affects 30% of patients infected with Trypanosoma cruzi (T. cruzi). Patients with CCC have a poorer prognosis and survival when compared with cardiomyopathy patients with non-inflammatory etiology, such as idiopathic dilated cardiomyopathy (IDC). In cardiac remodeling process, there is a restructuring of the extracellular matrix (ECM), largely mediated by proteins such as proteolytic enzymes, matrix metalloproteinases (MMPs) and their specific inhibitors (TIMPs). The alteration and/or activity of some these particular enzymes is associated with cardiovascular disease. Taking this into account, the hypothesis of this study is that the expression profile and activity of MMPs and their TIMPs inhibitors in the CCC will be different from those found in IDC. The gene expression was evaluated by qRT-PCR, the MMP protein expression: -1, -2, -3, -8, -9, -12-13 and EMMPRIN by \"Western blotting\" and the following TIMP inhibitors: -1 , -2, -3, -4 and RECK and MMP-2 and -9 activity by zymography, in myocardial samples (left ventricle) of CCC and IDC patients and organ donors (Control) obtained upon transplantation. Although some of these changes in the expression of MMPs, TIMPs and RECK were shared with the IDC, we observed that patients with CCC have increased MMP-2 and MMP-9 activity and exclusive increase in MMP-9 protein. Through the ratio of MMP-2 and MMP-9 activity with protein expression of TIMPs and RECK inhibitors, we found that the increase in MMP-2 and MMP-9 activity and the decrease in TIMP: -1, -2, -3, and -4 and TIMP -1, -2 and -3, respectively, in myocardial samples of CCC patients causes an imbalance in their activation and inhibition, contributing to the myocardium remodeling. The fraction of interstitial collagen as stained by Picrosirius Red, indicates increase in collagen in patients with CCC and IDC, indicating that the increase of MMP-2 and MMP-9 activity is modulating the synthesis and conformation of collagen organization, contribute to fibrosis in patients with CCC. Aiming to verify whether these MMPs and their inhibitors would be under post-transcriptional regulation, we performed in silico analysis and it was identified 8 microRNAs (miR): miR-21, miR-29-5p, miR-146a-5p, miR-155-5p , miR-188-5p, miR-214-3p, miR-491-5p and miR885-5p, but no correlation was found with the MMPs and their inhibitors, suggesting that these proteins are not under post-transcriptional regulation by miRs analyzed. Together our results suggest that differential expression of MMPs and their TIMPs inhibitors studied contribute to fibrosis, myocardial remodeling and cardiac dysfunction observed in patients with CCC. Thus, this work may help in elucidating the development of mechanisms of the pathogenesis of Chagas disease
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Avaliação dos efeitos da anestesia peridural torácica sobre as alterações miocárdicas associadas à morte encefálica: estudo experimental / Assessment of the effects of thoracic epidural anesthesia on myocardial changes associated with brain death: an experimental studySilva, Isaac Azevedo 03 May 2013 (has links)
INTRODUÇÃO: Atualmente, a maior limitação ao transplante cardíaco, em todo o mundo, é a escassez de doadores cujo número está sempre aquém do número de pacientes portadores de doença cardíaca terminal, e esse hiato fica ainda maior pelo fato de cerca de 25 % dos corações doados não serem utilizados, por estarem acometidos por acentuada disfunção. A descarga catecolaminérgica associada à morte encefálica poderia ser um dos elementos implicados nesta disfunção. Assim, intervenções terapêuticas com intuito de minimizar o exacerbado estímulo simpático visam, em última instância, ampliar a oferta de órgãos para o transplante. OBJETIVOS: Investigar a hipótese de que a anestesia peridural torácica seja capaz de bloquear a tempestade autonômica inerente à morte encefálica por hipertensão intracraniana aguda, minimizando as alterações hemodinâmicas, reduzindo a resposta inflamatória e, por conseguinte, melhorando a condição do enxerto. MÉTODOS: Ratos Wistar machos (250-350 g) anestesiados (isoflurano 5 %) e monitorados continuamente para o registro da pressão arterial média foram submetidos à inserção de cateter no espaço peridural em nível torácico e, em seguida, submetidos à morte encefálica por hipertensão intracraniana aguda pela xxi insuflação de um cateter de Fogarty® introduzido por trepanação. Os animais (n = 28) foram alocados em 4 grupos: grupo salina - infusão de 20 uL de solução salina pelo cateter peridural antes da indução da morte encefálica; grupo bupi-pré - infusão de 20 uL de solução de bupivacaína a 0,5 % pelo cateter peridural, antes da indução da morte encefálica; grupo bupi-20 - infusão de 20 uL de solução de bupivacaína a 0,5 % pelo cateter peridural 20 minutos após a indução da morte encefálica; grupo bupi-60 - infusão de 20 ?L de solução de bupivacaína a 0,5 % pelo cateter peridural 60 minutos após a indução da morte encefálica. Após 6 horas os animais foram submetidos à eutanásia por exsanguinação. Foram realizadas dosagens séricas e no tecido cardíaco das citocinas interleucina (IL)-1beta e fator de necrose tumoral (TNF)-alfa pelo método de ELISA. As moléculas de adesão endoteliais, vascular adhesion molecule (VCAM)-1 e intercellular adhesion molecule (ICAM)-1, proteínas envolvidas no processo de apoptose, Bcl-2 e caspase-3, e a alfa-actina foram avaliadas no tecido miocárdico por técnica imunohistoquímica. Cortes longitudinais do coração foram corados com hematoxilina/eosina e avaliados quanto à presença de edema, infiltrado leucocitário e congestão vascular. Contagens totais de leucócitos circulantes foram realizadas antes da indução da morte encefálica e 3 e 6 horas após. RESULTADOS: Logo após a insuflação do cateter de Fogarty® todos animais evoluíram com sinais clínicos de morte encefálica: midríase bilateral fixa e ausência de reflexo corneano. O aumento súbito e efêmero da pressão arterial foi observado em todos os animais, à exceção do grupo que recebeu a bupivacaína previamente à indução da morte encefálica (grupo bupi-pré) (p<0,05). Houve acentuada e progressiva leucopenia em todos os grupos. As citocinas IL-1beta, TNF-alfa, tanto no soro quanto no miocárdio, não apresentaram diferenças significativas entre os grupos. As moléculas de adesão VCAM-1 e ICAM-1, as proteínas Bcl-2 e caspase-3, a alfa-actina, bem como a análise histológica do miocárdio não apresentaram diferenças significativas entre os grupos. CONCLUSÕES: A anestesia peridural torácica foi efetiva em bloquear o pico hipertensivo associado à morte encefálica. Contudo, tal bloqueio não se correlacionou a alterações na concentração de citocinas, expressão de moléculas de adesão, expressão de proteínas envolvidas com o processo apoptótico e alfa-actina, e alterações histológicas e do leucograma. Portanto, a tempestade autonômica não parecer ser a responsável pela ativação da resposta inflamatória e, em última instância, pela disfunção miocárdica associada à morte encefálica / BACKGROUND: Currently, the main limitation to cardiac transplantation, worldwide, is the shortage of donors whose number is always smaller than the number of patients with terminal heart disease, and this gap is even greater because about 25 % of donated hearts are not used due to severe dysfunction of unknown cause. Brain-death associated catecholaminergic storm may be implicated in this dysfunction. Thus, therapeutic interventions aiming to reduce the sympathetic stimulation result, ultimately, in an increase in the number of organs for transplantation. OBJECTIVES: To investigate the hypothesis that thoracic epidural anesthesia is capable of blocking the sympathetic discharge inherent to brain death, by acute intracranial hypertension, minimizing hemodynamic changes, and reducing the inflammatory response improving, therefore, the graft outcome. METHODS: Male Wistar rats (250 - 350 g) anesthetized (5 % isoflurane) and continuously monitored to record mean arterial pressure, underwent insertion of a catheter into the epidural space, at the thoracic level. Brain death was induced by acute intracranial hypertension by inflating an intracranially inserted Fogarty catheter. The animals (n = 28) were divided into 4 groups: saline group - infusion of 20 uL of saline through the epidural catheter before induction of brain death; pre-bup group - infusion of 20 uL of bupivacaine through epidural catheter before induction of brain death; bup-20 group - infusion of 20 uL of bupivacaine through epidural catheter 20 min after induction of brain death; bup-60 group - infusion of 20 uL of bupivacaine through epidural catheter 60 min after induction of brain death. After 6 h the animals were exsanguinated. Serum and cardiac tissue concentrations of cytokines, interleukin (IL)-1beta and tumor necrosis factor (TNF)-alfa, were performed by ELISA. The endothelial adhesion molecules, vascular adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1, proteins involved in apoptosis, Bcl-2 and caspase-3, and ?-actin were evaluated in myocardial tissue by immunohistochemistry. Longitudinal sections of the heart were stained with hematoxylin/eosin and evaluated for the presence of edema, vascular congestion and leukocyte infiltration. White blood cell counts were obtained prior to induction of brain death, 3 and 6 h thereafter. RESULTS: Clinical signs of brain death, fixed dilated pupils and absence of corneal reflex, were observed immediately after catheter insuflation. The sudden increase in mean arterial pressure was observed in all animals except in those receiving bupivacaine prior to brain death induction (pre-bup) (p<0.05). There was a marked and progressive leukopenia in all groups. Cytokine levels, IL-1beta and TNF-alfa, in serum and cardiac tissue, showed no significant differences among groups. Adhesion molecules, VCAM-1 and ICAM-1, the proteins, Bcl-2, caspase-3 and ?-actin, and the histological analysis of the myocardium showed no significant differences among groups. CONCLUSIONS: The thoracic epidural anesthesia was effective to block the hypertensive peak associated with brain death. However, this blockage does not correlate to changes in the levels of cytokines, expression of adhesion molecules and expression of apoptosis-linked proteins, and alfa-actin. Furthermore, no changes in histological analysis and white blood cell counts were observed. The autonomic storm does not seem to be responsible for the activation of the inflammatory response and, ultimately, for the myocardial dysfunction associated with brain death
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