Fundamentos - Identificar pacientes ambulatoriais que necessitam de recursos terciários de hospital de referência voltado para a prática cardiológica é inerente à responsabilidade assistencial. Compete reconhecer pacientes sob maior risco de prognóstico desfavorável, o que pode ser feito pelo emprego de métodos estatísticos tradicionais. Com o mesmo fito, as redes neurais têm sido objeto de interesse. Formulamos a hipótese de que as redes neurais, alimentadas a partir de variáveis selecionadas com o emprego de estatística tradicional, pudessem contribuir para a avaliação prognóstica de pacientes com insuficiência cardíaca. Objetivos - Avaliar o prognóstico de pacientes com diagnóstico de insuficiência cardíaca com o emprego de métodos da estatística de sobrevivência associada com a rede neural artificial. Delineamento - Estudo de coorte retrospectiva a partir de dados assistenciais de pacientes que receberam o diagnóstico de insuficiência cardíaca, identificação das variáveis associadas ao prognóstico com o emprego da estatística tradicional e alimentação da rede neural perceptron de múltiplas camadas (Neuro XL Predictor - OLSOFT Software Development) com essas variáveis. Local - Ambulatório cardiológico com alto volume de atendimentos voltado para pacientes do Sistema Único de Saúde (SUS) em hospital acadêmico de referência terciário. Participantes - 2.128 pacientes consecutivos, que receberam o diagnóstico de insuficiência cardíaca de 2 de julho de 2003 a 2 de julho de 2007. Desfecho - óbito por qualquer causa. Análise de dados - À análise descritiva e exploratória, seguiu-se a avaliação da probabilidade de sobrevida pelo método de Kaplan Meier, seguida de análise inferencial com o emprego do teste de log-rank e do modelo de riscos proporcionais de Cox. Identificadas as variáveis associadas ao prognóstico de sobrevida, foi desenvolvida a rede neural nas diferentes fases de aprendizado- treinamento e com o recurso do algoritmo de treinamento backpropagation. A rede neural foi desenvolvida em cinco fases: fase 1 - aprendizado-treinamento (n=968 óbitos com informação completa); fase 2 - avaliação e aplicação (pacientes vivos até 2012); fase 3 - comparação da previsão de sobrevida com o emprego rede ( pacientes vivos até 2012) com a sobrevida observada; fase 4 - reensaios para aprendizados com novos desfechos (óbitos em 2013 e 2014); fase 5 - avaliação do aprendizado da rede na fase 4 (pacientes vivos e falecidos). A acurácia, a sensibilidade, a especificidade, o valor preditivo positivo e o valor preditivo negativo dos melhores modelos na previsão da sobrevida obtidas com a rede neural foram avaliados, considerando as duas funções de ativação (tangente hiperbólica e zero-based log sigmoid). Para tanto, foi preciso determinar intervalos de corte definidos por critério clínico de razoabilidade de expectativa do tempo de sobrevida e acerto calculado pela rede. A estimativa da previsibilidade e do erro também foi avaliada com o emprego da função de perda. Resultados - A análise estatística (n=2.128 pacientes) revelou as seguintes variáveis associadas ao prognóstico: idade (p < 0,001), índice de massa corpórea (p < 0,001), pressão arterial diastólica (p < 0,001), etiologia da insuficiência cardíaca (p < 0,001), classe funcional (p < 0,001), espessura do septo interventricular (p=0,037), diâmetro diastólico do ventrículo esquerdo (p < 0,001), diâmetro do átrio esquerdo (p=0,025), potássio sérico (p=0,015), colesterol total (p < 0,001), creatinina (p < 0,001) e a presença de diabetes melito (p=0,034). Os modelos de redes neurais com melhor previsibilidade foram obtidos pela categorização do tempo de sobrevida inferior a 2 anos, entre 2 anos e 6 anos, e superior a 6 anos. Nos pacientes com tempo de sobrevida observado superior a 6 anos, a partir da consulta inicial, com intervalo de corte de 3 anos, a estimativa feita com o emprego da rede neural demonstrou sensibilidade 93,0% (com ambas as funções de ativação), especificidade 76,4% ou 77,5% (dependendo da função de ativação), valor preditivo negativo 97,4% (com ambas as funções de ativação) e valor preditivo positivo 53,6% ou 54,7% (dependendo da função de ativação). Nos pacientes com tempo de sobrevida observado entre 2 anos e 6 anos, a partir da data do início dos sintomas, com intervalo de corte de 2 anos, obtivemos sensibilidade 89,8% (com ambas as funções de ativação), especificidade 72,5% ou 76,5%, valor preditivo positivo 86,3% ou 88,0% e valor preditivo negativo 78,7% ou 79,6% (dependendo da função de ativação). Nos pacientes com tempo de sobrevida observado inferior a 2 anos, a partir da data do início dos sintomas, com intervalo de corte de 1 ano, a estimativa com o emprego da rede neural demonstrou sensibilidade 87,2% (com ambas as funções de ativação), especificidade de 62,5% ou 66,7% (dependendo da função de ativação), valor preditivo positivo 82,0% ou 83,7% (dependendo da função de ativação) e valor preditivo negativo 71,4% ou 72,7% (dependendo da função de ativação). O erro da previsão de sobrevida com o emprego da rede neural, estimado com o auxílio da função de perda, variou de 4,4 meses até 1,1 anos. Conclusões - O emprego da rede neural alimentada por variáveis selecionadas com o emprego de estatística de sobrevivência tradicional pode ser método profícuo na avaliação prognóstica de pacientes com insuficiência cardíaca. A previsibilidade de estimativa de sobrevida alcançada com o uso de rede neural foi menor nos pacientes com quadros clínicos de menor tempo de evolução, comparativamente aos pacientes com maior tempo de evolução; no primeiro caso permitiria sugerir quadros mais instáveis em relação aos casos mais estáveis, isto é, aqueles com tempo de evolução maior / Background - Identifying outpatients who need tertiary resources of a referral cardiology hospital includes recognizing those at higher risk of unfavorable prognosis. Studies aimed at this objective may be accomplished with traditional statistics. Neural networks have been studied as a promising tool in the assessment of patients´ prognosis. We hypothesized that the neural networks developed with variables selected through traditional statistics might contribute to the prognostic evaluation of patients with heart failure. Objectives - To evaluate the prognosis of patients with heart failure using methods of survival statistics combined with the resources of artificial neural networks. Design - Retrospective cohort study from a database of patients previously diagnosed with heart failure, identification of variables associated with prognosis using traditional statistics, development of a neural network perceptron of multiple layers (Neuro XL Predictor - OLSOFT Software Development) with these variables. Setting - outpatient clinic from an academic tertiary cardiology center Participants - 2128 consecutive patients who received the diagnosis of heart failure between July 2, 2003 and July 2, 2007. Outcomes - death for any cause. Data analysis - Statistical evaluation was performed for descriptive and exploratory analysis and was followed by Kaplan Meier survival probability, and inferential analysis using the log-rank test and the Cox proportional hazards model to identify the variables associated with prognosis. Variables thus selected were then input for the neural network in the different stages of learning-training, with the backpropagation algorithm. The neural network was developed in 5 phases: phase 1 - learning / training (n = 968 deaths with complete information); phase 2 - evaluation and application (patients alive until 2012); phase 3 - comparison of the predicted versus the observed survival using the network (patients alive until 2012); phase 4 - re-tests for learning with new outcomes (deaths in 2013 and 2014); phase 5 - assessment of network learning in phase 4 (living and deceased patients). The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of the best models in the prediction of survival obtained with the neural network were evaluated taking into account the two activation functions (hyperbolic tangent and zero-based log sigmoid) and the cut-off intervals defined by clinical criteria of reasonableness of expected survival time and the estimated estimate by the network. The estimation of predictability and error was also evaluated using the loss function. Results - Statistical analysis (n = 2128 patients) revealed the following variables associated with prognosis: age (p < 0.001), body mass index (p < 0.001), diastolic blood pressure (p < 0.001), heart failure etiology (P < 0.001), functional class (p < 0.001), interventricular septum thickness (p = 0.037), left ventricular diastolic diameter (p < 0.001), left atrial diameter (p = 0.025), serum potassium level, total cholesterol (p < 0.001), serum creatinine level (p < 0.001) and the presence of diabetes mellitus (p = 0.034). The models of neural networks with better predictability were obtained with the categorization of the survival time of less than 2 years, between 2 and 6 years, and over 6 years. In patients with a survival time of more than 6 years from the initial consultation, with a cut-off interval of 3 years (or 1095 days), the estimate using the neural network showed sensitivity 93.0% (with both activation functions), specificity of 76.4% or 77.5% (depending on the activation function), negative predictive value 97.4% (with both activation functions) and positive predictive value 53.6% or 54.7% (depending on the function of activation). In patients with a survival time of 2 to 6 years from the onset of symptoms, with a cut-off interval of 2 years (or 730 days), we obtained 89.8% sensitivity (with both activation functions), specificity 72,5% or 76.5%, positive predictive value 86.3% or 88.0% and negative predictive value 78.7% or 79.6% (depending on the activation function). In patients with a survival time of less than 2 years from the onset of symptoms, with a cut-off interval of 1 year (or 365 days), the estimate using the neural network showed a sensitivity of 87.2% (with both activation functions), specificity of 62.5% or 66.7% (depending on the activation function), positive predictive value 82.0% or 83.7% (depending on the activation function) and negative predictive value 71.4% or 72.7% (depending on the activation function). The error of survival prediction with the use of the estimated neural network with the aid of the function of absolute loss ranged from 4.4 months to 1.1 years. Conclusions - The use of selected variables input in the neural network with the use aid of traditional survival statistics, may be a useful method for the prognostic evaluation of patients with heart failure. Estimates were less accurate in patients with a shorter duration of symptoms relative to those with symptoms for a long time; in the first case it would suggest more unstable disease relative to those with more stable disease, namely with symptoms for a long time

Contexte : L'insuffisance cardiaque (IC) est un syndrome aux étiologies variées, et hétérogène dans ses présentations cliniques, dont l'incidence augmente avec l'âge et dont le pronostic reste sombre. Les facteurs pronostiques dans l'IC ont été largement décrits dans la littérature, en particulier dans l'IC à fraction d'éjection réduite (ICFER), à plus ou moins long terme. Des interventions thérapeutiques médicamenteuses, chirurgicales, ou complexes sont recommandées pour traiter ce syndrome. Objectifs : Les objectifs de ce travail étaient d'évaluer la valeur pronostique des marqueurs de fibrose chez les patients hypertendus, de décrire la survie et d'identifier les facteurs pronostiques chez les patients en IC, à très long terme chez les ICFER, et à 1 an chez les IC à fraction d'éjection préservée (ICFEP), et de mesurer l'impact sur les hospitalisations de 2 interventions complexes recommandées. Méthodes : Une première étude de cohorte a été menée chez des patients hypertendus, avec un recueil à l'inclusion des dosages sériques des marqueurs du renouvellement de la matrice extracellulaire cardiaque (MRMEC) et un suivi pendant 6 ans. Deux autres études de cohorte ont permis d'identifier les facteurs pronostiques de décès à 15 ans chez des patients ICFER (EPICAL), et à 1 an chez les ICFEP (Odin). Enfin, les données du PMSI ont permis de mesurer l'impact pronostique de la prise en charge dans une unité spécialisée (UTIC) et d'une prise en charge de type disease management (ICALOR). Résultats : La première étude a mis en évidence la valeur pronostique des MRMEC chez des patients hypertendus. L'étude EPICAL a montré que l'âge avancé, le diabète, l'insuffisance rénale chronique, l'ancienneté de l'IC, les antécédents de décompensation, la tachycardie, une fraction d'éjection réduite, et une hyponatrémie étaient associés à une mortalité plus élevée à 15 ans chez les ICFER. L'étude ODIN a montré la valeur pronostique négative de facteurs sociaux comme le fait de vivre seul ou la limitation des activités, chez les ICFEP. Enfin, les prises en charge en UTIC et par le réseau ICALOR étaient associées à une diminution des hospitalisations pour IC, mesurable à l'échelle populationnelle. Conclusion : Ces travaux permettent d'envisager de nouvelles pistes de prévention primaire et secondaire, afin de diminuer l'incidence, la morbidité et la mortalité liées à l'IC / Context: Heart failure (HF) is a heterogeneous syndrome with various aetiologies. HF incidence increases with age, and the prognosis remains poor. Prognostic factors have been widely described in the literature, especially in HF with reduced ejection fraction with short-term or mid-term follow-up. Medications, surgical interventions, and complex interventions are part of the current guidelines. Objectives: To assess the prognostic value of fibrosis markers in hypertensive patients; to describe the survival and to detect prognostic factors, first at 15 years in HF patients with reduced ejection fraction (HFREF), and second at one year in HF patients with preserved ejection fraction (HFPEF); and to assess the prognostic impact of 2 complex interventions on HF hospitalisations. Methods: Cardiac extracellular matrix serum markers (CEMSM) were assessed at baseline in a first cohort of hypertensive patients followed-up for 6 years. Two other cohort studies were used to detect prognostic factors associated with very-long term mortality in HFREF (EPICAL), and with 1-year mortality in HFPEF (Odin). And the national diagnostic related group database was used to assess the prognostic impact of a HF unit (UTIC) and a disease management programme (ICALOR). Results: The first cohort study highlighted the prognostic value of CEMSM in hypertensive patients. In EPICAL study, older age, diabetes mellitus, chronic renal failure, time from HF onset, history of hospitalisations for worsening HF, tachycardia, a low left ventricular ejection fraction, and hyponatraemia were associated with a higher mortality in HFREF patients. In Odin study, we highlighted the negative prognostic impact of social factors, such as living alone or daily activity limitation, in HFPEF patients. Both UTIC and ICALOR were associated with a decrease in HF hospitalisations compatible with a population impact. Conclusion: These studies offer new insights for primary and secondary prevention strategies that could eventually lead to decrease HF incidence, HF morbidity, and HF mortality

Malgré le bénéfice observé par de nouvelles thérapeutiques, le devenir des patients hospitalisés pour une insuffisance cardiaque aigue (ICA) reste sombre. Ce pronostic péjoratif est en partie influencé par la survenue fréquente d’événements thrombotiques qui sont à parfois directement à l’origine du décès des patients. Les mécanismes physiopathologiques de cette hypercoagulabilité pourraient être considérés comme des cibles thérapeutiques d’intérêt. L’objectif de ce travail est de démontrer qu’une défaillance des systèmes biologiques contrôlant la thrombose est impliquée dans la physiopathologie de l’ICA. Notre travail met en évidence la présence d’une hypercoagulabilité de ces patients qui se caractérise par une génération de thrombine exagérée pendant la phase aigüe de la décompensation cardiaque et qui se normalise ensuite à distance. Cette élévation de la génération de thrombine est la conséquence d’une augmentation du nombre de microparticules procoagulantes circulantes et d’une altération de l'activité d’un système naturel anticoagulant représenté par la voie de la protéine C / Acute heart failure (AHF) is a syndrome with an increasing prevalence and a high mortality whose management is challenging given the incomplete understanding of its pathophysiology. This doomed prognosis is partly influenced by thromboembolic events and is often the cause of death. The present study demonstrates a significant shift towards a prothrombotic biological profile at the acute phase of decompensated heart failure. Using a comprehensive exploration of the dynamics of thrombin generation and inhibition, we found an increased overall thrombin-generating capacity in AHF patients during hospital course. Both increased in circulating procoagulant microparticles and impairment in the downregulation of thrombin generation by the anticoagulant C protein pathway represent mechanisms contributing to this hypercoagulable state in AHF

La dyspnée aigue due à une congestion pulmonaire dans le cadre d’une insuffisance cardiaque aiguë (ICA) est un motif d’admission fréquent aux Urgences. Actuellement, l’ICA est deux fois plus fréquente et est associée à un risque deux fois plus élevé de décès (8%) que les syndromes coronariens aigus (SCA). La prise en charge en pré hospitalier et aux urgences est devenue une étape clé du parcours de soin de ces patients. Ces dernières années ont vu émerger de nouveaux paradigmes autour de la prise en charge de l’ICA mettant en perspective la complexité de cette pathologie. On parle désormais de syndrome d’insuffisance cardiaque aiguë (SICA), terminologie qui souligne la pluralité des situations cliniques et la diversité des profils congestifs. Cependant, l’évaluation de la répartition de la congestion au cours d’un SICA, même s’il existe peu de données sur ce sujet, est actuellement principalement faite sur des arguments cliniques ; l’échographie pulmonaire et l’estimation du volume plasmatique (ePVS, basé sur un calcul intégrant hémoglobine et hématocrite) pourraient permettre de mieux préciser les profils congestifs. Plusieurs études rapportent que la rapidité et l’exactitude du diagnostic étiologique de dyspnée aigue sont associées au pronostic des patients. Malgré l’existence d’outils diagnostiques (biomarqueurs, examens de radiologie), l’incertitude quant au diagnostic étiologique reste importante dans le contexte d’un service d’urgence, ce qui rend difficile la diminution du « Time to therapy » promue par les recommandations de la société européenne de cardiologie 2016. Les objectifs de notre travail étaient d’identifier des profils de congestion distincts d’insuffisance cardiaque aigue, de préciser la valeur diagnostique et pronostique de ces profils dans le contexte d’une dyspnée aigue, et de déterminer si l’effet thérapeutique des modalités de prise en charge initiale en urgence est dépendant de ces profils congestifs. Dans le cadre de notre travail, nous avons pu montrer sur la base des analyses réalisées dans la cohorte DeFSSICA que les outils permettant de mieux préciser le profil congestif des patients (notamment l’échographie pulmonaire et l’ePVS) sont peu utilisés aux urgences. Dans un deuxième travail, nous avons montré sur la cohorte PARADISE (NCT02800122) – conçue dans le cadre de ce doctorat, que l’altération de fonction rénale, l’hyponatrémie et la dysglycémie sont associée de façon significative au pronostic des patients atteints de dyspnée aigue. Dans un troisième travail, nous avons montré que le volume plasmatique estimé est un outil diagnostique performant de SICA et qu’un niveau plus important de congestion évaluée par l’ePVS est associé à une mortalité intra-hospitalière des patients admis pour dyspnée aigue plus élevée. Notre travail a aussi permis de concevoir et démarrer l’étude PURPLE (Pathway and Urgent caRe of dyspneic Patient at the emergency department in LorrainE district – NCT NCT03194243) qui collecte les données cliniques et paracliniques des patients admis pour dyspnée aigue aux urgences de façon prospective dans la région Lorraine. Par ailleurs, ce travail de thèse a aussi permis de concevoir et faire financer le projet EMERALD-US (Evaluation de la faisabilité de la Mise en œuvre et de la performance d’un algorithme d’EchogRraphie Aux urgences pour Le diagnostic de Dyspnée aigue-UltraSound) qui vise à valider un algorithme spécifique aux urgences utilisant l’échographie pulmonaire, cardiaque et vasculaire pour le diagnostic étiologique de dyspnée aigue / Acute dyspnea due to pulmonary congestion in acute heart failure (AHF) is a common reason for admission to the ER. Currently, AHF is twice as common and associated with a twofold higher risk of death (8%) than acute coronary syndromes (ACS). Pre-hospital and emergency care has become the cornerstone of care of these patients. In recent years, new paradigms have emerged surrounding AHF management, highlighting the complexity of this disease. Hence the use of the term acute heart failure syndrome (AHFS), a terminology underscoring the plurality of clinical situations and the diversity of congestive profiles. However, the assessment of congestion distribution during an AHFS is currently predominantly based on clinical arguments in spite of limited data. Alternatively, lung ultrasound (LUS) and estimation of plasma volume (ePVS, based on hemoglobin and hematocrit) could allow for a better assessment of congestive profiles. Several studies report that the rapid and accurate etiological diagnosis of acute dyspnea is associated with prognosis. Despite the availability of diagnostic tools including clinical exam, biomarkers and radiology, there is still considerable uncertainty regarding etiological diagnosis in the emergency department (ED) setting, hence rendering it difficult in reducing the « Time to therapy » advocated by the recommendations of the European Cardiology Society 2016 for AHF. The objectives of the present work were to identify distinct congestion profiles of AHF, to clarify the diagnostic and prognostic value of these profiles in the context of acute dyspnea, and to determine whether the therapeutic effect of initial emergency management modalities is dependent on these congestive profiles. In the course of our work, we were able to demonstrate in the DeFSSICA cohort that the tools allowing a better assessment of the patient's congestive profile (particularly LUS and ePVS) are rarely used in ED. In a second study, we showed in the PARADISE cohort (NCT02800122) - designed as part of this PhD research project - that impaired renal function, hyponatremia and dysglycemia are significantly associated with prognosis in patients with acute dyspnea. In a third study, we showed that the ePVS is an effective AHF diagnostic tool and that a higher congestion level assessed by ePVS is associated with higher in-hospital mortality of patients admitted for acute dyspnea. Our work also enabled us to design and initiate the PURPLE (Pathway and Urgent caRe of dyspneic Patients at the emergency department in LorrainE district - NCT03194243) study, which collects clinical and paraclinical data of patients admitted for acute dyspnea on a prospective basis. Lastly, this PhD research project enabled designing and obtain funding for the EMERALD-US project (Evaluation of the feasibility of implementing and performance of an Emergency Echography algorithm for the diagnosis of Acute Dyspnea-UltraSound) which aims to validate an original algorithm specific to emergency situations using lung, cardiac and vascular ultrasound for the etiological diagnosis of acute dyspnea

Bakgrund: Ungefär 2 % av Sveriges befolkning lider av hjärtsvikt, vilket motsvarar cirka 200 000 personer. Globalt är 26 miljoner människor drabbade av hjärtsvikt. Hjärtsvikt har en större inverkan på livskvaliteten än många andra kroniska sjukdomar. Patienterna påverkas både psykiskt, fysiskt och socialt. Prognosen för hjärtsviktspatienter är dålig, av nydiagnostiserade hjärtsviktspatienter avlider 23 % inom ett år. Hälso- och sjukvårdskostnaden för hjärtsviktspatienter uppgick till 7,7 miljarder kronor 2017, vilket motsvarade 2,7 % av Sveriges totala sjukvårdskostnader. Syfte: Syftet med litteraturöversikten är att beskriva patienters erfarenheter av att leva med hjärtsvikt. Metod: Examensarbetet har utformats som en litteraturöversikt. Vetenskapliga artiklar har hämtats från databaserna Cinahl och PubMed. Resultatet baseras på 15 vetenskapliga artiklar, 14 kvalitativa och en mixed method artikel. Resultat: Patienternas erfarenheter av att leva med hjärtsvikt kunde delas in i sex huvudkategorier: Copingstrategier, fysisk påverkan, psykisk påverkan, social påverkan, möte med hälso- och sjukvården samt patienters kunskap. Trots att hjärtsvikt är ett somatiskt sjukdomstillstånd, upplevde flera patienter att hjärtsvikten hade en omfattande inverkan på den psykiska hälsan. Slutsats: Hjärtsvikt påverkar patienten på alla plan, och det är individuellt hur den drabbade upplever sin situation. Genom att hälso- och sjukvårdspersonalen tillämpar ett personcentrerat förhållningssätt, där vården utgår från den unika patientens berättelse och utformas i samråd med patienten, stärks egenvårdsförmågan och därmed även livskvaliteten. / Background: About 2 % of the Swedish population suffer from heart failure, which corresponds to about 200 000 people. Globally, 26 million people suffer from heart failure. Heart failure has a greater impact on the quality of life than many other chronic diseases. Patients are affected both mentally, physically and socially. The prognosis for heart failure patients is poor, 23 % by newly diagnosed heart failure patients will die within one year. Healthcare costs for heart failure patients amounted to SEK 7.7 billion in 2017, which corresponded to 2.7 % of Sweden's total healthcare costs. Aim: The aim of this literature review was to describe patients’ experiences of living with heart failure. Method: A literature review. Research articles has been collected from the Cinahl and PubMed databases. The results are based on 15 research articles, 14 qualitative and one mixed method article. Results: The patients’ experiences of living with heart failure could be divided into six main categories: Coping strategies, physical impact, psychiatric impact, social impact, meeting with health care and patient knowledge. Although heart failure is a somatic disease state, several patients experienced that the heart failure had an extensive impact on mental health. Conclusion: Heart failure has an impact on the patient in several ways, and it is individual how the affected person experiences his or her situation. By the healthcare staff applying a person-centered approach, where the care is based on the unique patient's story and is designed in collaboration with the patient, the self-care ability and thus also the quality of life is strengthened.

L’insuffisance cardiaque (IC) est un problème majeur de santé publique. La pénurie des greffons cardiaques et la résistance de nombreux patients aux traitements conventionnels ont poussé les chercheurs à développer de nouvelles thérapeutiques dont la thérapie cellulaire. Bien que l’idée initiale de la thérapie cellulaire ait été de repeupler la partie nécrosée du cœur par l’administration de cellules viables et fonctionnelles, leur disparition rapide alors que les bénéfices perdurent dans le temps a conduit à l’hypothèse que les cellules agiraient via un mécanisme paracrine. Les vésicules extracellulaires (VE), incluant les exosomes et les microparticules, seraient principalement impliquées dans ce processus. Elles agiraient ainsi comme de véritables navettes transportant des biomolécules actives permettant d’activer des voies de réparation endogènes dans le tissu traité. Ce projet de thèse a pu mettre en évidence : 1) La non-infériorité des VE issues de progéniteurs cardiovasculaires (Pg) dérivés de cellules souches embryonnaires humaines par rapport à leurs cellules d’origine dans un modèle murin d’IC chronique (ICC). Ces VE activeraient des voies de signalisation endogènes impliquées dans la stimulation de la prolifération cellulaire, la survie cellulaire, la réparation de l’ADN et la diminution de la fibrose. Leur contenu moléculaire spécifique, et notamment les microARN, pourrait être impliqué dans ces phénomènes. 2) L’importance du choix du type cellulaire dans la production de VE efficaces sur le plan thérapeutique puisque ni les VE dérivées de cardiomyocytes matures ni celles de cellules souches mésenchymateuses n’ont eu d’effets bénéfiques sur la fonction cardiaque de souris en ICC. 3) L’implication des VE dans l’effet paracrine des cellules, confirmée par l’amélioration de la fonction cardiaque chez des souris présentant une ICC traitées avec des VE issues de Pg dérivés d’iPS. Des tests fonctionnels in vitro ont montré que les VE auraient un rôle pro-angiogénique, pro-prolifératif et amélioreraient la survie des cellules. Une thérapie a-cellulaire aurait une réelle pertinence clinique en réglant une partie des problèmes techniques, immunologiques et sécuritaires associés aux greffes de cellules. Si cette hypothèse est confirmée, il pourrait en résulter une simplification des problèmes réglementaires, une diminution des coûts de production et de ce fait une plus grande diffusion clinique de la méthode. / Heart failure (HF) is a major public health concern. The lack of donor hearts and the resistance of numerous patients to conventional treatments has led scientists to develop new therapies such as cell therapy. The initial goal of cell therapy was to repopulate the infarcted heart by directly injecting viable and functional cells. However, the rapid disappearance of the transplanted cells contrasts with their long term, ongoing functional benefits, suggesting that cells may act through a paracrine mechanism. Extracellular vesicles (EV), including exosomes and microparticles, may be key to this process, acting as shuttles to transport bioactive macromolecules that stimulate endogenous repair pathways in the host tissue. This PhD project demonstrates: 1) The non-inferiority of EV secreted by cardiovascular progenitors (Pg) derived from human embryonic stem cells as compared to their parent cells in a mouse model of chronic HF (CHF). These EV could act by the activation of endogenous signaling pathways implicated in cell proliferation, survival, DNA repair and decreased fibrosis. Their specific content, such as miRNA, could be involved in these benefits. 2) The importance of the cell type in the production of therapeutically effective EV, since EV derived from mature cardiomyocytes and mesenchymal stem cells did not improve cardiac function in mice with CHF. 3) The importance of EV in paracrine effects of cells, confirmed by the improvement of cardiac function in mice with CHF treated with EV secreted by Pg derived from iPS cells. In vitro data shows that EV might have pro-angiogenic, pro-proliferative and pro-survival effects. An acellular therapy should be clinically relevant by reducing technical, immunological and safety problems associated with cell transplantation. If this hypothesis is confirmed, regulatory concerns would be simplified and production costs reduced, facilitating large-scale production.

As doenças cardiovasculares lideram as causas de morte em vários países, inclusive no Brasil, sendo a insuficiência cardíaca (IC) uma das enfermidades mais frequentes. Associações entre ancestralidade genética e susceptibilidade ao desenvolvimento da IC já foram relatadas em diferentes populações. O presente estudo teve como objetivo estimar as ancestralidades global e local de 492 pacientes com IC, identificar regiões e ancestralidades genômicas associadas à IC, seus fatores de risco (diabetes e hipertensão) e à mortalidade causada pela IC, por meio do mapeamento por miscigenação (AM, admixture mapping). Utilizando 182.090 Polimorfismos de Nucleotídeo Único (SNPs, Single Nucleotide Polymorphisms) comuns à nossa população e a três populações ancestrais (europeia, africana e ameríndia) foram realizadas as análises das ancestralidades global e local. Todos os pacientes apresentaram maior proporção de ancestralidade global europeia, média de 0,618±0,218. As análises de AM da IC e da diabetes não mostraram nenhuma região associada, nas três ancestralidades avaliadas. No estudo de AM da hipertensão houve associação estatisticamente significativa com a ancestralidade local africana no cromossomo 2 (chr2p25.3) (p=4,65x10-5). Nessa região estão mapeados 7 RNAs não codificantes, 2 RNAs longos de região intergênica não codificadores de proteína, 44,93% do gene Syntrophin Gamma 2 (SNTG2) e o gene que codifica uma proteína de transmembrana (TMEM18). A análise de AM da mortalidade por IC foi realizada com os mesmos 492 pacientes com IC, usando o modelo caso-controle, sendo o grupo de casos (n=248) composto por pacientes em óbito no final de 4 anos de avaliação, e o grupo de controles (n=244), de indivíduos que ainda estavam vivos no final desse mesmo período. Foi observada associação estatisticamente significativa com a ancestralidade local europeia no cromossomo 6 (chr6p22.3) (p=6,805x10-5). Nessa região estão mapeados 30,74% do gene Ataxina 1 (ATXN1) e o gene Guanosina Monofosfato Redutase (GMPR). O mapeamento fino nessa região, com 7.916 SNPs, apresentou dois marcadores genéticos, rs1042391 e rs2142672, com resultados significativos (p=1,140x10-4, p=3,921×10-4, respectivamente). O alelo em homozigose TT do rs1042391 foi associado a um aumento de 21% ao risco de morte por IC (HR=1.21, p=0,0013), enquanto que o alelo em homozigose CC do rs2142672 foi associado a um aumento de 51% ao risco de morte por IC (HR=1.51, p=0,0004). Estes são achados iniciais e, como tal, devem ser considerados como hipóteses geradoras. Apesar disso, ficou demonstrado a utilidade do estudo de AM para identificar regiões com diferentes ancestralidades genômicas que podem contribuir para o risco de doenças complexas em populações geneticamente miscigenadas. Esses dados podem auxiliar na compreensão da etiologia genética da hipertensão e da mortalidade em pacientes com IC, relacionados à ancestralidade, podendo servir como ponto de partida para estudos funcionais na tentativa de aprofundar os conhecimentos dos processos biológicos que levam à hipertensão e à IC. Estudos futuros são necessários para replicar as associações encontradas, detectar variáveis causais que conduzem essas associações e explorar aplicações clínicas para as regiões de genes consistentemente associadas a mortalidade em pacientes com IC e à hipertensão / Cardiovascular diseases lead the causes of death in several countries, including Brazil, with the heart failure (HF) being one of the most frequent diseases. Associations between genetic ancestry and susceptibility to the development HF have already been reported in different populations. The present study aimed to estimate the global and local ancestry of 492 HF patients, and identify genomic regions and ancestry associated with HF, HF risk factors (diabetes and hypertension) and HF mortality, through admixture mapping (AM). Using 182,090 Single Nucleotide Polymorphisms (SNPs) common to our population and to three ancestral populations (European, African and Amerindian) the analyses of global and local ancestry were performed. All patients showed a higher proportion of European global ancestry, mean of 0.618±0.218. The AM analysis of HF and diabetes did not show any associated regions, in the three ancestries evaluated. In AM of hypertension there was a statistically significant association with African local ancestry on chromosome 2 (chr2p25.3) (p=4,65x10-5). In this region are mapped 7 non-coding RNAs, 2 long intergenic non-protein coding RNAs, 44.93% of the Syntrophin Gamma 2 gene (SNTG2) and the gene encoding a transmembrane protein (TMEM18). The AM analysis of HF mortality was performed with the same 492 HF patients, using case-control model, case group (n=248) was composed of patients who died at the end of 4 years of evaluation, and control group (n=244) included individuals who were still alive at the end of that period. A statistically significant association with European local ancestry on chromosome 6 (chr6p22.3) (p=6.805x10-5) was observed. In this region are mapped 30.74% of the gene Ataxin 1 (ATXN1) and the Guanosine Monophosphate Redutase gene (GMPR). The fine mapping in this region, with 7,916 SNPs, presented two genetic markers, rs1042391 and rs2142672, with significant results (p=1,140x10-4, p=3,921×10-4, respectively). The TT homozygous allele of rs1042391 was associated with 21% increase risk of HF death (HR=1.21, p=0,0013), while the CC homozygous allele of rs2142672 was associated with 51% increase risk of HF death (HR=1.51, p=0.0004). These are initial findings and, as such, should be considered as generating hypotheses. Despite this, it was demonstrated the utility of the AM study to identify regions with different genomic ancestry that may contribute to the risk of complex diseases in genetically mixed populations. These data may contribute to understand the genetic etiology of hypertension and mortality in HF patients, related to ancestry, and may serve as a starting point for functional studies in an attempt to deepen the knowledge of the biological processes that lead to hypertension and HF. Future studies are needed to replicate the associations found, to detect causal variables that lead these associations, and to explore clinical applications for gene regions consistently associated with death in patients with HF and hypertension

Os efeitos da utilização da terapia de ressincronização cardíaca (TRC) em pacientes com cardiopatia chagásica (CCC) são pouco conhecidos. O objetivo desse trabalho foi comparar o efeito dessa terapia em pacientes com CCC e não-chagásica. Foram estudados, retrospectivamente, todos os pacientes submetidos à ressincronização cardíaca, associados ou não ao cardioversor-desfibrilador implantável (CDI) no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo no período de julho de 2007 a dezembro de 2017. Para comparar a mesma variável em dois momentos diferentes foi utilizado Teste de Wilcoxon. Para a comparação de proporções foi utilizado o teste exato de Fisher. A análise de sobrevida foi feita utilizando-se o método de Kaplan-Meier com o \"Long rank test\" para comparar a sobrevida entre os grupos. Para a análise das variáveis associadas à mortalidade pós-implante utilizou-se a análise de regressão de Cox. Noventa e oito pacientes foram incluídos e divididos em três grupos de cardiopatia: chagásica (CCC) com 42 pacientes (42,9%); isquêmicos (ISQ) com 13 (13,3%) e nãoisquêmico não-chagásico (NINC) com 43 (43,9%). Os pacientes que receberam implante de TRC foram 71,4% e TRC associado ao CDI foram 28,5%. Não havia diferença estatisticamente significativa entre os grupos na avaliação das características clínicas, exceto pela predominância de pacientes do gênero masculino no grupo ISQ. Em relação aos bloqueios de condução intraventriculares, havia menor quantidade de bloqueio de ramo esquerdo (BRE) espontâneo e maior quantidade de BRE induzido no grupo CCC. As demais características eletrocardiográficas e ecocardiográficas eram semelhantes entre os grupos. A sobrevida de pacientes que recebem a TRC foi baixa após 48 meses de implante, independentemente do tipo de miocardiopatia e a despeito da melhora significativa da classe funcional e estreitamento do QRS dos pacientes. Todavia, a sobrevida em pacientes chagásicos foi significativamente menor quando comparada as demais miocardiopatias. Ademais, a melhora da fração de ejeção do ventrículo esquerdo (FEVE) e a redução do diâmetro diastólico final do ventrículo esquerdo (DDFVE) ocorreram significativamente apenas no grupo NINC. O aumento da idade, FEVEreduzida, presença de atraso da condução intraventricular não especificada (ACINE) e de bloqueio de ramo direito (BRD) e baixa classe funcional estão associadas a maior risco de morte após implante. As taxas de complicações cirúrgicas foram baixas em todos os grupos. A taxa de óbito cirúrgico é compatível com a gravidade desses pacientes. Conclui-se que a CCC apresenta resposta clínica à TRC, mas a mortalidade após 48 meses é maior que em outras cardiopatias. / The effects of using cardiac resynchronization therapy (CRT) in patients with Chagas\' heart disease (CCC) are poorly understood. The objective of this study was to compare the effect of this therapy in patients with CCC and non-Chagas\' disease. We retrospectively studied all patients submitted to cardiac resynchronization associated or not with the implantable cardioverter defibrillator (ICD) at the Clinical Hospital of Ribeirão Preto Medical School at the São Paulo University from July 2007 to December 2017. We use Wilcoxon\'s test to compare the same variable in two different times. Fisher\'s exact test was used to compare proportions. Survival analysis was done using the Kaplan-Meier method with the Long rank test to compare survival between groups. Cox regression analysis was used to analyze the variables associated with post-implantation mortality. Ninety-eight patients were included and divided into three groups: cardiopathy: chagasic (CCC) with 42 patients (42.9%); ischemic (ISQ) with 13 patients (13.3%) and non-ischemic non-chagasic (NINC) with 43 (43.9%). The patients who received CRT implantation were 71.4% and CRI associated CRT were 28.5%. There was no statistically significant difference between the groups in the assessment of clinical characteristics, except for the predominance of male patients in the ISQ group. In relation to intraventricular conduction blockades, there was a lower amount of spontaneous left bundle branch block (LBBB) and greater amount of LBBB induced in the CCC group. The other electrocardiographic and echocardiographic characteristics were similar between groups. The survival of patients receiving CRT was low after 48 months of implantation, regardless of the type of cardiomyopathy and despite significant improvement in functional class and QRS narrowing of patients. However, survival in chagasic patients was significantly lower when compared to other cardiomyopathies. In addition, the improvement of left ventricular ejection fraction (LVEF) and the reduction of the left ventricular end-diastolic dimension (LVEDF) occurred significantly only in the NINC group. Increased age, reduced LVEF, presence of unspecified intraventricular conduction delay and left bundle branch block, and low functional class are associated with a higher risk of death after implantation. Therates of surgical complications were low in all groups. The surgical death rate is compatible with the severity of these patients. It is concluded that CCC presents a clinical response to CRT, but mortality after 48 months is higher than in the other cardiopathies.

Fundamento: Na descompensação da insuficiência cardíaca, pode ocorrer o baixo débito cardíaco, nessa situação o uso de inotrópico pode ser necessário. Se o acesso venoso for periférico, a infusão venosa prolongada de inotrópicos pode levar à flebite. Por outro lado, o acesso venoso central pode apresentar complicações. O Cateter Central de Inserção Periférica (PICC) pode ser uma opção nessa situação. O objetivo do presente estudo foi avaliar a incidência de flebite com o uso do PICC em comparação ao acesso venoso periférico. Métodos: em estudo clínico randomizado foram selecionados pacientes com insuficiência cardíaca congestiva avançada, em uso de inotrópico endovenoso; plaquetas >= 50.000/mm3 e fração de ejeção do ventrículo esquerdo (FEVE) < 0,45. Os pacientes foram randomizados para receberem o PICC ou manter o acesso venoso periférico. O desfecho principal foi à ocorrência de flebite. Os dados foram analisados pela regressão logística. Resultados: Foram incluídos 40 pacientes no Grupo PICC e 40 pacientes no grupo controle. A mediana da idade foi de 61,5 (IQR=16) anos, a FEVE foi de 24,0 (IQR= 10) % e a dose da dobutamina foi de 7,73 (IQR = 5,3) mcg/kg*min. No Grupo PICC a ocorrência de flebite foi de 2,5 % (1 paciente) enquanto no grupo controle foi de 95% (38 pacientes), com razão dos riscos (HR) de 0,1% (IC 95%: 0,0 a 1,6%, P < 0,001). Conclusões: O uso de PICC foi associado a redução da incidência de flebite durante a infusão endovenosa contínua de dobutamina em pacientes com baixo débito cardíaco durante internação por insuficiência cardíaca descompensada / Background: During decompensated heart failure, the use of intravenous inotropes can be necessary. With peripheral venous access, prolonged infusions can cause phlebitis. However, traditional central venous catheters have possible complications. Peripherally inserted central catheters (PICCs) may be an alternative to traditional catheters. Our objective was to compare the incidence of phlebitis between PICCs and catheters used to achieve peripheral venous access. Methods: In a randomized clinical trial, 40 patients were randomized to the PICC group and 40 patients were randomized to thecontrol group. The inclusion criteria were advanced heart failure, ejection fraction < 0.45, and platelets > 50,000/mm3. The patients were randomly assigned to receivea PICC or keep their peripheral venous access. The primary endpoint was the occurrence of phlebitis. Results: We included 40 patients in the PICC group and 40 patients in the control group. The median age was 61.5 (interquartile range [IQR]=16) years, the ejection fraction was 0.24 (IQR=0.10), and the dobutamine dose was 7.73 (IQR=5.3) mcg/kg*min. Phlebitis occurred in 1 patient (2.5%) in the PICC group and in 38 patients (95.0%) in the control group, with a hazard ratio of 0.1% (95% confidence interval [CI]: 0.0%-1.6%, P < 0.001). Conclusion: PICCs were associated with a lower incidence of phlebitis in patients hospitalized for decompensated heart failure with low cardiac output during intravenous dobutamine infusions

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.