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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
611

Erfarenheter av information hos hjärtsviktspatienter : En litteraturöversikt / Experiences of Information in Heart Failure Patients : A literature review

Asp, Sanna, Nordström, Rebecca January 2018 (has links)
Bakgrund: Hjärtsvikt drabbar många personer såväl i Sverige som internationellt. Information är grundläggande för hantering av sjukdomen samt för att förebygga negativa följder. Som teoretisk utgångspunkt användes KASAM, känslan av sammanhang. Syfte: Att beskriva hjärtsviktspatienters erfarenheter av information. Metod: En litteraturöversikt med tolv kvalitativa artiklar har gjorts. Artiklarna har analyserats med Fribergs femstegsmodell. Resultat: I litteraturöversiktens resultat framkommer två teman, "Tillfredsställelse med information" samt "Former för information". Hjärtsviktspatienter hade skilda erfarenheter gällande information. Vissa patienter hade upplevt att informationen var tillfredsställande och tillräcklig medan andra upplevde informationen som bristande. Informationen som gavs upplevdes ofta vara i behov av anpassning utifrån patientens förutsättningar. Patienter hade erfarenheter av aspekter som såväl hindrade som underlättade information. I vissa fall använde patienter andra källor utöver vården för att hitta information. Slutsatser: För att omvårdnaden kring hjärtsviktspatienter ska bli tillgodosedd krävs att sjuksköterskan tar sig tid och ger anpassad information till patienterna. Sjuksköterskan bör se till att anpassa informationen utifrån patienternas förutsättningar, önskemål, resurser och behov. Litteröversikten visar att det finns rum för förbättring angående givning av information till hjärtsviktspatienter. / Background: Heart failure affect many people both in Sweden and internationally. Information is key to managing the illness and preventing negative consequences. KASAM (SOC), sense of coherence, was used as the theoretical starting point. Aim: To describe heart failure patients' experiences of information. Method: With Friberg's five step model as the analytic method, a literature review was conducted on twelve qualitative studies about heart failure patients' experiences of information. Result: The literature review's result shows two themes, "Satisfaction with Information" and "Forms of Information". Heart failure patients had different experiences concerning information. Some patients experienced the information as satisfactory and sufficient while others experience the information as lacking. The information that was given was often experienced as in need of adaptation to fit the patient's situation.  Patients had experiences of aspects that both hindered and facilitated information. In some cases, patients used sources other than the health care to find additional information. Conclusion: In nursing of heart failure patients the nurse has to take time to inform and to adapt information to the patients. The nurse should make sure to adapt the information after the patients' condition, wishes, resources and needs. The literature review shows that there's room for improvement concerning information given to heart failure patients.
612

Faktorer som främjar patienters egenvård vid hjärtsvikt: : En litteraturöversikt / Factors that promote patients self-care in heart failure: : A literature review

Khalil, Amanda, Moges, Elsa January 2018 (has links)
Bakgrund: Hjärtsvikt är sex gånger vanligare hos patienter i 65-74 års åldern jämfört med patienter i 45-54 års åldern. Hjärtsvikt påverkar patienters hälsa och välbefinnande då hjärtsvikt påverkar den fysiska och psykiska förmågan. Symtomen vid hjärtsvikt leder till fler sjukhusvistelser och långa sjukskrivningar. Egenvården är en viktig del av behandlingen.  Trots fördelarna med egenvård genomför inte patienter egenvård. Patienter med hjärtsvikt är i behov av åtgärder som främjar deras egenvård. Syfte: Syftet var att beskriva faktorer som främjar patienters egenvård vid hjärtsvikt. Metod: Metoden i studien var en litteraturöversikt. 12 artiklar analyserades varav 10 av dessa var kvalitativa och 2 var av en mixad metod. Resultat: Det framkom att patienter önskade information om egenvård. Ett utbildningsprogram ökade genomförandet av egenvård. Patienter föredrog hemsjukvård före andra vårdformer då den ökade deras delaktighet. Kognitiv beteendeterapi kunde förändra patienters tankesätt och lindra depression. Stödet patienter fick från sjuksköterskor och familj hade en stor betydelse i genomförandet av egenvård. Motivationskällor och självförtroendet påverkade genomförandet av egenvård.  Slutsats: Patienter bör genomföra egenvård för att undvika symtomförsämring, sjukhusvistelser, sjukskrivningar och uppnå god hälsa och välbefinnande. Utbildning, kognitiv beteendeterapi, hemsjukvård, delaktighet, stöd, motivation och självförtroende främjar egenvård hos patienter med hjärtsvikt. / Background: Heart failure is six times more common among patients between the ages 65-74 compared to patients between the ages 45-54. Heart failure affects patients health and wellbeing. Heart failure symptoms lead to more hospitalizations and long sick leaves. Self-care is an important part of the treatment. Patients do not perform self-care despite the benefits of it. Patients with heart failure are in need of measures that promote their selfcare. Aim: the aim was to describe factors that promote patients self-care in heart failure. Method: The method of the study was a literature review. 12 articles were analyzed where 10 of them were qualitative and 2 of a mixed method. Result: Patients want information about self-care. An educational program enhances self-care. Patients prefer home healthcare because it increases their participation. Cognitive behavioral therapy can change patients thoughts and ease depression. The support patients receive from nurses and family members has a big effect on their self-care. Motivation and confidence affects self-care. Conclusion: Patients should perform self-care to avoid symptom deterioration, hospital visits, sick leave and achieve good health and well-being. Education, cognitive behavioral therapy, home healthcare, participation, support, motivation and confidence promote selfcare in patients with heart failure.
613

Desenvolvimento de um protótipo para monitoramento à distância de pacientes com insuficiência cardíaca por short message service

Pedraza, Leticia Lopez January 2017 (has links)
Objetivo: Desenvolver e testar um sistema de monitoramento à distância por short message service (SMS) para pacientes com insuficiência cardíaca (IC) agudamente descompensada. Método: A elaboração do protótipo foi desenvolvida em três etapas: a primeira, foi a definição de todas as funcionalidades previstas; a segunda, procurou a codificação dos módulos do programa; a terceira, consistiu na realização dos testes, para garantir seu funcionamento pleno. O programa desenvolvido enviava dois tipos de mensagens: com perguntas, que deveriam ser respondidas pelos pacientes, e com reforços educativos, que não necessitavam de respostas. Além disso, o sistema gerava alarmes em caso de ausência de resposta ou conforme um fluxograma para detectar congestão. Esta dinâmica permitia o contato imediato com o participante para confirmar os dados recebidos e dar orientações sobre as medidas necessárias para auxiliá-lo. Para o teste do protótipo, foram acompanhados 10 pacientes com internação por descompensação aguda da IC que estavam nas unidades clínicas ou na unidade de cuidados coronarianos do Hospital de Clinicas de Porto Alegre. Após a alta, as mensagens que exigiam respostas foram enviadas durante uma semana (duas pela manhã e duas à noite). Os SMS educativos foram enviados uma vez a cada dois dias. Resultados: Participaram do teste do protótipo, 10 pacientes. A média de idade foi de 67±13 anos. Os pacientes eram predominantemente do sexo masculino e moravam acompanhados por familiares. A fração de ejeção média foi de 35±7%. Dos 30 pacientes potencialmente elegíveis no período de teste, 14 foram incluídos. Destes, quatro não tiveram alta no momento do teste e um não completou o seguimento de sete dias por internação por síndrome coronariana aguda. Dos 264 SMS enviados, 247 foram respondidos. Dez dos SMS não respondidos coincidiram com a falta de luz gerada por fortes tormentas que ocorreram na cidade. Os demais SMS não foram respondidos porque os pacientes não os viram (quatro) ou porque eles esqueceram (três). O alarme foi acionado sete vezes: três pacientes acordaram com falta de ar durante duas noites consecutivas e quatro pacientes se sentiram mais cansados durante dois dias consecutivos. Nenhum paciente aumentou dois Kg em três dias. Todos os pacientes tomaram as medicações prescritas durante o seguimento. A enfermeira do estudo orientou os pacientes que geraram alarme no sistema. Conclusões: O sistema de monitoramento à distância foi desenvolvido com êxito e, durante o teste, foi possível detectar algumas limitações – que foram corrigidas. Entre os participantes que completaram o estudo, observamos uma alta taxa de resposta e evidência preliminar de melhorias na autogestão da IC. / Objective: To develop and test a short message service remote monitoring system for patients with acute decompensated heart failure (HF). Method: The elaboration of the prototype was developed in three stages: the first one was the definition of all the expected functionalities; the second sought coding of the program modules; the third consisted of the tests, which ensured its full operation. The program sent two types of messages: questions that should be answered by the patients, and educational reinforcements that did not require answers. In addition, the system generated alarms in case of no response or according to a flow chart to detect congestion in the patient previously created by the team. This system allows the immediate contact with the participant to confirm the received data and to give the necessary orientations to him. For the prototype test we included 10 patients hospitalized for acute decompensation of HF who were in the clinical units or coronary care unit of the Clinical Hospital of Porto Alegre. After discharge, messages that required responses were sent for one week (two in the morning and two in the evening). The educational SMS was sent once every two days. Results: Ten patients participated in the prototype test. The mean age was 67 ± 13. The patients were predominantly males and lived with relatives. The ejection fraction was 35 ± 7%. Of the 30 potentially eligible patients in the trial period, 14 were included. Of these, four were not discharged at the time of the test and one did not complete the seven-day follow-up for hospitalization for acute coronary syndrome. Of the 264 SMS sent, 247 were answered. Ten of the unanswered SMS coincided with the lack of light generated by the strong storms in the city. The remaining SMS were not answered because the patients did not see them (four) or they forgot these (three). The alarm was triggered seven times: three patients woke up with shortness of breath for two consecutive nights and four patients felt more fatigued for two consecutive days. No patient increased two Kg in three days. All patients took the prescribed medications during follow-up. The study nurse guided the patients who generated alarm in the system. Conclusions: The remote monitoring system was successfully developed and during the test it was possible to visualize some limitations that were corrected. Among the participants who reform the study, we observed a high response rate and preliminary evidence of improvements in self-management of HF.
614

Signalling regulation of cardiac hypertrophy by the mitogen activated protein kinase (MAPK) pathways

Jin, Jiawei January 2012 (has links)
Heart failure induced by cardiac hypertrophy is a cause of high mortality in the world and has been the fastest growing cardiovascular disease over the past decade. Cardiac hypertrophy is characterised as a reactive increase in cardiac mass growth with a complex of ventricular remodelling. It occurs initially as a compensatory response to an increased workload but eventually leads to cardiac dysfunction. An in-depth understanding of cardiac hypertrophy and the capacity to regulate it has profound clinical implications. The MAPK pathways provide an important connection between external stimuli and intracellular signals for cardiac hypertrophic response. At least four MAPK subfamilies have been identified: extracellular-regulated protein kinases 1 and 2 (ERK1/2), ERK5, c-Jun NH2-terminal protein kinases (JNKs) and p38 MAPKs. Mitogen-activated protein kinase kinase 4 (MKK4), a vital activator of JNK and p38 is implicated as an important mediator of hypertrophy. ERK5, an atypical MAPK, is also involved in both hypertrophic growth and cardiomyocyte survival. However, conflicting data have been yielded from previously-published studies, since the results are based entirely on experiments conducted in cultured cardiomyocytes or transgenic and conventional knockout mouse models. To elucidate their biological roles and underlying signalling mechanisms in hypertrophy, mice with a cardiomyocyte-specific deletion of MKK4 or ERK5 (MKK4cko and ERK5cko mice) were generated in the present study. In response to pathological hypertrophic stresses including pressure overload or isoprenaline stimulation, MKK4cko mice developed exacerbated pathological hypertrophy with increased cardiomyocyte apoptosis, impaired cardiac function and remarkably upregulated NFAT (nuclear factor of T-cell) transcriptional activity. However, MKK4cko mice exhibited a similar extent of swimming exercise-induced physiological hypertrophy compared with the controls. In response to pathological hypertrophic stimuli, ERK5cko mice were resistant to hypertrophic growth, foetal gene induction and ventricular fibrosis, which is associated with repressed activation of MEF2 (myocyte enhancer factor 2). ERK5 deficiency also caused a profound increase in cardiomyocyte apoptosis which accounted for the impaired cardiac function. In conclusion, the present study provides biological evidence that clarifies in vivo functions of MKK4 and ERK5 in hypertrophy. MKK4 acts a protective role against pathological hypertrophy through inhibiting NFAT signalling, but it is not necessary for the regulation of physiological hypertrophy. ERK5 is essential for pathological hypertrophic remodelling and cardiomyocyte survival and its function in hypertrophic remodelling is mediated through regulation of MEF2 activity. Taken together, these data presented in my thesis advances knowledge about biological functions of MAPK pathways in the heart.
615

Assoziation zwischen Angstsymptomen und der Serum-Konzentration von Endothelin-1 bei diastolischer Dysfunktion / Association between anxiety symptoms and serum of endothelin-1 concentrations in patients with diastolic dysfunction

Roggenthien, Maren Susan 20 August 2018 (has links)
No description available.
616

A Pharmacovigilance Approach for Assessing Cardiovascular, Osteological, and Carcinogenic Risk Associated with Thiazolidinedione Drugs Used in the Treatment of Type 2 Diabetes Mellitus

Davidson, Melissa Anne 04 September 2018 (has links)
Diabetes is a chronic and debilitating disease that affects nearly half a billion people worldwide with the vast majority of diabetics suffering from Type 2 diabetes mellitus (T2DM), a disease characterized by insulin insensitivity that often requires pharmacotherapy to effectively maintain target blood sugar levels. The thiazolidinedione (TZD) class of drugs consists of oral hypoglycaemic agents used alone or in combination with other antidiabetic drugs to treat T2DM. The drugs within this class, which include rosiglitazone and pioglitazone, were originally heralded as providing novel first and second-line treatment of T2DM with glycaemic control and physiological effects comparable to, and in some cases, better than, first-line treatments such as metformin. However, over time they have also been associated with adverse cardiovascular, osteological, and carcinogenic effects in some, but not all clinical trials, observational studies, and meta-analyses. Given the conflicting evidence to date on the safety of TZD drugs, their role in the treatment of T2DM continues to be debated and epidemiological gaps remain. The objectives of this doctoral research are fourfold: 1) to conduct an in-depth review of the epidemiology of TZD pharmacotherapy including pharmacokinetics and modes of action, the results of previous studies investigating health risks and benefits associated with TZD treatment, and new and future uses for this class of drugs; 2) to determine whether diabetic patients treated with TZDs are at increased risk of adverse cardiovascular outcomes; 3) to assess whether TZD pharmacotherapy is associated with an increased risk of bone fractures and whether risks differ depending on fracture site and patient sex; and, 4) to investigate associations between TZD use and risk of bladder cancer. Specific research questions were investigated using nested case-control analyses designed to capture incident users of antidiabetic drugs and electronic health data from Cerner Health Facts®, an electronic medical record database that stores time-stamped patient records from more than 480 contributing hospitals throughout the United States. Findings from this work are reported in a series of manuscripts, including a published review paper. Key findings include: 1) TZD use was associated with an increased risk of incident myocardial infarction and congestive heart failure compared to never use of TZD drugs with a trend towards a potential early treatment effect within the first year of exposure to pioglitazone; 2) TZD use was associated with an increased risk of closed bone fractures among Type 2 diabetics with use of pioglitazone or rosiglitazone associated with an increased risk across multiple fracture sites in women, but only rosiglitazone use in men and only at peripheral fracture sites; 3) use of either pioglitazone or rosiglitazone were associated with an increased risk of incident bladder cancer compared to never users, however, a low number of bladder cancer cases resulted in underpowered analyses; and, 4) insulin use in a hospital setting may replace a patient's normal course of antidiabetic therapy which, when combined with other potential sources of bias in traditional nested case-control studies using hospital-based data, may lead to overestimation or underestimation of adverse health risks associated with non-insulin antidiabetic therapies. Although these findings warrant replication, the results of the research contained within this dissertation suggest that caution should be exercised when prescribing diabetic patients TZD drugs if they have cardiovascular, osteological, or carcinogenic risk factors. Additional pharmacovigilance studies should also continue to strive to better understand the health risks related to TZD therapy, especially as new therapeutic roles for TZDs in the prevention and treatment of some cancers, inflammatory diseases, and other conditions in non-diabetic populations are being explored.
617

Função mecânica do átrio esquerdo em cães com degeneração valvar crônica de mitral / Left atrial mechanical function in dogs with chronic mitral valve degeneration

Matheus Matioli Mantovani 05 May 2016 (has links)
O objetivo desse estudo foi determinar se os índices de função, volume (VAE) e área (AAE) do átrio esquerdo (AE) podem ser utilizados para avaliar a gravidade da degeneração valvar crônica de mitral (DVCM) em cães, bem como diagnosticar a insuficiência cardíaca congestiva (ICC) nestes pacientes. A hipótese é que o aumento dos volumes e decréscimo da função atrial esquerda possa estar associado com a gravidade da DVCM e também com a ICC. Oitenta cães foram incluídos em um estudo clínico transversal observacional e prospectivo, sendo agrupados de acordo com a gravidade DVCM. Os cães foram igualmente distribuídos nos grupos A, B1, B2 e C + D, de acordo com o estadiamento para DVCM proposto pelo American College of Veterinary Internal Medicine. A mudança fracional da área (FAC) e a fração de ejeção atrial esquerda (FEAE) foram calculados com as seguintes equações: FAC total = 100 x (AAEmáxima AAEmínima) / AAEmáxima, FAC passiva = 100 x (AAEmáxima AAEpa) / AAEmáxima e FAC ativa = 100 x (AAEpa AAEminima) / AAEpa, cujas as mensurações foram realizadas no corte apical quatro câmaras; e FEAE Total = 100 x (VAEmáxima VAEmínima) / VAEmáxima, FEAE passiva = 100 x (VAEmáxima VAEpa) / VAEmáxima e FEAE ativa = 100 x (VAEpa VAEminima) / VAEpa, calculadas por meio do método biplanar área-comprimento, no corte apical quatro e duas câmaras. A FAC total, FAC ativa, FEAE total e FEAE ativa foram significativamente menores nos pacientes do grupo C+D do que as observadas nos demais grupos. Também foi observado que com o agravamento da DVCM ocorreu o aumento do VAEmáximo/kg, VAEpa/kg, VAEmínimo/kg, AAEmáximo/m2, AAEpa/m2, AAEmínimo/m2. Os volumes do AE, bem como suas áreas, apresentaram grande acurácia e aumentaram a capacidade para diagnosticar a ICC nos cães do DVCM. Conclui-se que a função atrial esquerda total e ativa é reduzida nos cães com ICC secundária a DVCM quando comparados aos cães saudáveis e naqueles com DVCM sem ICC. Além disso, os volumes e as áreas atriais podem ser utilizados para diagnosticar a ICC nesses pacientes / This study aimed to determine whether left atrial (LA) function indices, volume (LAV) and area (LAA) can be used to assess severity of mitral valve chronic degeneration (MVCD) in dogs, as well as to diagnose congestive heart failure (CHF) in these patients. The hypothesis stated that the increase in left atrial volumes and decrease in function are associated with the severity of MVCD and also with CHF. Eigthy dogs were included in a cross sectional prospective observational clinical study, grouped according to the severity of MVCD based on clinical signs and echocardiographic evaluation. Dogs were equitatively distribuited among groups A, B1, B2 and C + D, according to MVCD staging proposed by the American College of Veterinary Internal Medicine. The fractional area change (FAC) and left atrial ejection fraction (LAEF) were calculated based on the following equations: total FAC = 100 x (LAAmaximum LAAminimum) / LAAmaximum, passive FAC = 100 x (LAAmaximum LAApa) / LAAmaximum and active FAC ativa = 100 x (LAApa LAAminimum) / LAApa, which measurements were performed in four chamber apical view; and total LAEF = 100 x (LAVmaximum LAVminimum) / LAVmaximum, passive LAEF = 100 x (LAVmaximum LAVpa) / LAVmáximum and active LAEF = 100 x (LAVpa LAVminimum) / VLAVpa , calculated by biplanar arealength method in four and two-chambers apical view. The total and active FAC, total LAEF and active LAEF were significantly smaller in pacients from group C+D than the observed in the other groups. With increasing severity of MVCD there was increase in LAVmaximum/kg, LAVpa/kg, LAVminimum/kg, LAAmaximum/m2, LAApa/m2, LAAminimum/m2. LA volumes, as well as LA areas had a good performance as diagnostic methods, with high accuracy and increased capacity for heart failure detection in dogs with MVCD. In conclusion, left atrial total and active function are reduced in dogs with HF secondary to MVCD when compared with healthy dogs and dogs with MVCD without HF. Moreover, atrial volumes and areas can be used to diagnose HF in these patients
618

Excessiva atividade de remodelamento ventricular sinaliza limitada resposta terapêutica ao manejo agressivo da insuficiência cardíaca avanaçada / Excessive activity of ventricular remodeling signals limited therapeutic response in the aggressive management of advanced heart failure

Mascarenhas, Marcello Ávila January 2005 (has links)
Introdução: Níveis de fator de necrose tumoral–alfa (TNF-α), N-peptídeo do pró-colágeno III (PIIINP) e metaloproteinase de matriz –1 (MMP-1), marcadores biológicos de remodelamento ventricular, estão elevados em pacientes com insuficiência cardíaca (IC), talvez refletindo elevadas pressões de enchimento. A correlação destes marcadores com variáveis clínicas e hemodinâmicas permanece pouco compreendida, particularmente no contexto ambulatorial da IC. Objetivo: Avaliar níveis séricos de marcadores biológicos de remodelamento ventricular em pacientes com IC, comparando tratamento guiado por ecocardiografia (ECO), buscando redução de pressões de enchimento, versus tratamento convencional (CLÍNICO), baseado em sinais e sintomas. Métodos: Ensaio clínico randomizado. Pacientes estáveis com IC e fração de ejeção menor do que 40% foram alocados entre os grupos de tratamento e submetidos a ecocardiograma e coletas de sangue no início do estudo e em 180 dias. TNF-α e MMP- 1 foram medidos por ELISA, e PIIINP, por radioimunoensaio. Resultados: Incluiu-se 80 pacientes, com 59 ± 15 anos e fração de ejeção de 26 ± 7%; 25% isquêmicos e 52% masculinos. Houve redução dos marcadores biológicos intragrupos, não havendo diferença entre os tratamentos. No grupo CLÍNICO, os níveis de TNF-α, MMP-1 e PIIINP apresentaram diferenças estatisticamente significativas entre os momentos basal e final (respectivamente, 3,11 ± 2,90 versus 1,24 ± 0,60 pg/mL p < 0,0003; 2,66 ± 1,00 versus 1,16 ± 0,40 ng/mL p < 0,0001; 6,12 ± 2,60 versus 3,89 ± 1,60 μg/L p < 0,0001). De maneira semelhante, tal diferença também foi observada no grupo ECO para os três marcadores (respectivamente, 3,90 ± 4,90 versus 1,40 ± 1,30 pg/mL p < 0,0001; 2,50 ± 0,90 versus 1,09 ± 0,40 ng/mL p < 0,0001; 6,09 ± 2,60 versus 3,50 ± 1,30 μg/L p<0,0001). Ao final da intervenção, no entanto, não foi observada diferença significativa dos valores de TNF-α , MMP-1 e PIIINP entre os dois grupos de tratamento (p = 0,7; p = 0,8; e p = 0,2; respectivamente). A combinação dos valores basais das variáveis biológicas gerou um escore que se associou significativamente com o comportamento final das pressões atrial direita e sistólica da artéria pulmonar. Pacientes com marcadores biológicos basais no quartil 75% mantiveram níveis superiores de pressões atrial direita (13 mmHg; p = 0,034) e sistólica de artéria pulmonar (60 mmHg; p = 0,007) ao final do seguimento. Conclusão: Independente do tratamento alocado, houve redução dos níveis de marcadores biológicos ao final do seguimento; no entanto, níveis basais mais elevados destes marcadores foram preditores de menor redução das pressões em átrio direito e sistólica da artéria pulmonar. Os dados sugerem que indicativos de intenso processo de remodelamento ventricular se associam à progressão da IC e a pressões de enchimento elevadas. / Introduction: Levels of tumor necrosis factor-alpha (TNF-α), N-terminal propeptide of type III collagen (PIIINP) and type 1 matrix metalloproteinase (MMP-1), biological markers of ventricular remodeling, are elevated in heart failure (HF) patients, perhaps reflecting elevated filling pressures. The correlation of these markers with clinical and hemodynamic variables remains poorly understood, particularly in the outpatient setting. Objective: To evaluate serum levels of ventricular remodeling biological markers in patients with HF, comparing a conventional clinically-oriented treatment (Conventional Therapy), based on clinical signs and symptoms, to an echocardiography-guided treatment (Echo-guided Therapy), aiming at a reduction in filling pressure levels. Methods: Randomized trial. Stable patients with HF and ejection fraction lower than 40% were allocated to the treatment groups and submitted to echocardiography and blood sampling at the beginning of the study and after 180 days. TNF-α and MMP-1 were measured by ELISA, and PIIINP, by radioimmunoassay. Results: Eighty patients at 59 ± 15 years and a mean ejection fraction of 26 ± 7% were included; 25% were ischemic and 52%, males. There was a reduction in intragroup biological markers, without difference between treatments. TNF-α, MMP-1 and PIIINP levels were statistically different between baseline and final in patients allocated to Conventional Therapy (respectively, 3.11 ± 2.90 versus 1.24 ± 0.60 pg/mL p < 0.0003; 2.66 ± 1.00 versus 1.16 ± 0.40 ng/mL p < 0.0001; 6.12 ± 2.60 versus 3.89 ± 1.60 μg/L, p < 0.0001). Similarly, such a difference was also observed in the Echo-guided Therapy for the 3 markers (respectively, 3.90 ± 4.90 versus 1.40 ± 1.30 pg/mL p < 0.0001; 2.50 ± 0.90 versus 1.09 ± 0.40 ng/mL p < 0.0001; 6.09 ± 2.60 versus 3.50 ± 1.30 mg/L p<0.0001). By the completion of the intervention, however, no significant difference was observed in the values of TNF-α, MMP- 1 and PIIINP between the 2 treatment groups (p = 0.7; p = 0.8; and p = 0.2; respectively). A composite score incorporating baseline biological marker levels was statistically associated to final right-sided pressure levels (right atrial pressure and pulmonary artery systolic pressure). Patients with baseline biological marker levels over percentile 75 maintained higher right atrial (13 mmHg; p = 0.034) and pulmonary artery systolic pressures (60 mmHg; p = 0.007) at the end of protocol. Conclusion: Regardless of allocated treatment group, biological marker levels were lower at the end of the follow-up; however, higher baseline levels of these markers were predictive of lower reductions in right atrial pressure and pulmonary artery systolic pressure. The data obtained suggest that indicators of an intense remodeling process are associated with elevated filling pressures and progression of HF.
619

Determinantes da fraqueza e propriedades contráteis da musculatura inspiratória na insuficiência cardíaca

Ribeiro, Paula Aver Bretanha January 2012 (has links)
A fraqueza muscular inspiratória pode estar presente em 30 a 50 % dos pacientes ambulatoriais com insuficiência cardíaca crônica, com implicações na qualidade de vida e prognóstico. Entretanto, não está claro quais características clínicas e comportamentais que estariam associadas a essa disfunção. Além disso, como não estão claros os mecanismos moleculares que conduzem a disfunção do diafragma. Parâmetros contráteis incluindo força de contração máxima, força passiva e cinética de pontes cruzadas podem estar alterados em pacientes com IC, e podem estar associados a FMI. Esta tese investigou, primeiramente, determinantes da FMI em comparação com a fraqueza muscular periférica (preensão manual), em pacientes com ICC. Neste estudo foram avaliadas variáveis clínicas, antropométricas e comportamentais destes pacientes. Os resultados demonstraram que apenas aproximadamente 50 % da FMI pode ser explicada pelas variáveis analisadas. Além disso, as variáveis associadas à fraqueza de preensão manual não são diferentes das encontradas em sujeitos saudáveis (gênero e idade). Entretanto, a força inspiratória máxima pode estar associada com marcadores de capacidade funcional do paciente. Em seguida, foram investigadas propriedades contráteis, ativas e passivas de miofibrilas de músculo cardíaco e diafragma, em um novo modelo animal de camundongos com insuficiência cardíaca desenvolvida por knockout para arginilação cardíaco-específica. Resultados do músculo cardíaco demonstram compatibilidade com a disfunção contrátil encontrada em humanos com insuficiência cardíaca congestiva, tais como redução da contração máxima, redução da força passiva e redução da cinética de relaxamento. Entretanto, nos resultados do músculo diafragma, encontramos aumento da força de contração máxima, o que pode sugerir uma mudança adaptativa compensatória associada ao aumento do trabalho inspiratório associado à insuficiência cardíaca crônica. Em conclusão, menos de 50 % da variância da força muscular inspiratória pode ser explicada por variáveis clínicas e comportamentais de pacientes com insuficiência cardíaca crônica. Em um modelo animal de insuficiência cardíaca que resulta em diminuição da contratilidade de cardiomiofibrilas, observa-se aumento da contratilidade das miofibrilas do diafragma, sugerindo que a fraqueza muscular inspiratória associada à insuficiência cardíaca crônica não seja secundária à disfunção contrátil da musculatura inspiratória. / The inspiratory muscle weakness may be present in 30-50% of outpatients with chronic heart failure, with implications for the quality of life and prognosis. However, it is unclear what clinical and behavioral characteristics that would be associated with this dysfunction. Moreover, as are unclear the molecular mechanisms leading to dysfunction of the diaphragm. Contractile parameters including contraction force maximum passive force and kinetics of cross-bridges can be altered in patients with HF, and may be associated with the IMF. This thesis investigated, firstly, the determinants of IMF in comparison to peripheral muscle weakness (handgrip) in patients with CHF. We evaluated clinical, anthropometric and behavioral disorders in these patients. The results showed that only about 50% of IMW can be explained by the variables. Furthermore, the variables associated with weakness of grip are not different from those found in healthy subjects (gender and age). However, maximum inspiratory force may be associated with markers of patient's functional capacity. Next, we investigated the contractile properties, assets and liabilities of myofibrils of cardiac muscle and diaphragm in an animal model of mice with heart failure developed by knockout arginilação cardiac-specific. Results show compatibility with the cardiac muscle contractile dysfunction found in human with congestive heart failure, such as reduction of maximum contraction, reduction and reduction of the passive force relaxation kinetics. However, the results of the diaphragm, we found increased maximum force of contraction, which may suggest a compensatory adaptive changes associated with increased inspiratory work associated with chronic heart failure. In conclusion, less than 50% of the variance in inspiratory muscle strength can be explained by behavioral and clinical variables of patients with chronic heart failure. In an animal model of heart failure that results in decreased contractility cardiomyofibrils, there was an increase in contractility of the diaphragm myofibrils, suggesting that inspiratory muscle weakness associated with chronic heart failure is not secondary to contractile dysfunction of the respiratory muscles.
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Développement et optimisation de capteurs de gaz à base de silicium : analyse des composés organiques volatils contenus dans l’air expiré par les patients atteints d’insuffisance cardiaque / Development and optimization of gas sensors based on silicon substrate : analysis of volatile organic compounds contained in exhaled breath of patients with heart failure

Boudjaoui, Selim 06 July 2018 (has links)
Les travaux développés dans ce manuscrit de thèse entrent dans le cadre du projet européen intitulé « Hearten », « A co-operative mHealth environment targeting adherence and management of patients suffering from Heart Failure (HF) ». Les acteurs de ce projet cherchent à développer une plateforme réseau multi compétences dont le but est le diagnostic précoce et le suivi des patients atteints d'insuffisance cardiaque. Elle permet l'enregistrement de différents paramètres vitaux de ces patients, comme la pression artérielle, le poids, les biomolécules contenus dans les biofluides, et leur consultation immédiate par les différents acteurs en charge du suivi des patients. L'objectif des travaux de recherche présentés dans ce manuscrit est de développer un capteur de gaz conductimétrique portable et miniaturisé, permettant la mesure en temps réel des VOCs caractéristiques du syndrome HF dans l'air expiré par les patients. La molécule d'acétone, connue dans la littérature pour être l'un des biomarqueurs les plus discriminants d'HF, a été particulièrement ciblée. Le capteur ainsi conçu est formé de paires de microélectrodes interdigitées (µIDEs) en or déposées sur substrat de silicium. La partie sensible du capteur consiste en une membrane polymérique électro-déposée à la surface du capteur qui est sensible à l'acétone. Les paramètres géométriques des µIDES ont été analysés et optimisés au cours de ces travaux afin d'améliorer la réponse et la sensibilité du capteur. Une plateforme d'analyse des gaz contenant l'ensemble de l'instrumentation associée à notre capteur a été développé. Les paramètres de l'instrumentation ont également été analysés et optimisés dans le même but. Nous avons ainsi étudié deux types de membranes polymériques sensibles à l'acétone. La première couche sensible développée est basée sur la co-polymérisation d'un polymère et de nanomatériaux dopants, le chitosan et les zéolites. La seconde couche sensible développée est quant à elle basée sur la co-polymérisation de polypyrrole et de métallophthalocyanines. Le capteur développé présente des performances optimales pour ce projet, dont notamment une limite de détection de l'ordre du ppm, ainsi que des temps de réponse et de recouvrement très courts. L'utilisation de ce capteur dans le cas de mesures cliniques est ainsi très prometteuse puisqu'il permet d'analyser plusieurs échantillons en temps réel, et ceux sur une durée de fonctionnement de plus d'une semaine. Le diagnostic rapide et la prise en charge du patient est donc facilité grâce à ce dispositif, dont les couts de fabrication sont très réduits / The work presented in this manuscript is part of the European project « Hearten », « A co-operative mHealth environment targeting adherence and management of patients suffering from Heart Failure (HF) ». The actors of this project are seeking for developing a multi-competence network platform whose goal is the early diagnosis and follow-up of patients with heart failure. It allows the recording of various vital parameters of these patients, such as blood pressure, weight, biomolecules contained in biofluids, and their immediate consultation by the different actors in charge of patient follow-up.The objective of research presented in this manuscript is to develop a portable conductometric gas sensor, allowing the measurement of characteristic VOCs of HF syndrome in exhaled air by patients. Acetone molecule, known in the literature as one of the most discriminating biomarkers of HF, has been particularly targeted. The sensor thus designed is based on pairs of gold interdigitated microelectrode etched on a silicon substrate. The sensitive part of the sensor consists of a polymeric membrane sensitive to acetone and electro-deposited on the surface of the sensor. The geometrical parameters of the µIDES have been analyzed and optimized during these works to improve the response and sensitivity of the sensor. A gas analysis platform including all the instrumentation associated with our sensor has been developed. The instrumentation parameters have also been analyzed and optimized for the same purpose.We studied two types of polymeric membranes sensitive to acetone. The first sensitive layer developed was based on the co-polymerization of a polymer and doping nanomaterials, chitosan and zeolites. The second sensitive layer developed was based on the co-polymerization of polypyrrole and metallophthalocyanines. The developed sensor provides optimal performance for this project, including a detection limit in the order of ppm level, as well as very short response and recovery times. The sensor can therefore be considered in the case of clinical measurements.The use of this sensor in the case of clinical measurements is very promising because it allows to analyze several samples in real time, and those over a period of operation of more than one week. Rapid diagnosis and patient management is therefore facilitated by this device, whose manufacturing costs are very low

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