191 |
Associação entre distúrbios respiratórios do sono, estresse oxidativo e doença arterial coronariana / Association among sleep disordered breathing, oxidative stress and coronary artery diseaseKlein, Cristini January 2010 (has links)
TÍTULO: Associação entre Distúrbios Respiratórios do Sono, Estresse Oxidativo e Doença Arterial Coronariana. INTRODUÇÃO: Evidências sugerem associação entre a doença arterial coronariana (DAC) e os distúrbios respiratórios do sono (DRS), porém o mecanismo que explica essa associação é incerto. Episódios repetitivos de hipóxia e reoxigenação vivenciados pelos indivíduos com DRS levam ao aumento de espécies reativas de oxigênio (ERO). ERO no interior dos eritrócitos podem ser detoxificadas pelas enzimas antioxidantes glutationa peroxidase (GPx), catalase (CAT) e superóxido dismutase (SOD). Ainda no citoplasma as ERO podem ser detoxificadas pela vitamina C ou ácido úrico. O estresse oxidativo é caracterizado por um desequilíbrio entre os níveis de ERO e antioxidantes. Este desequilíbrio promove lesão oxidativa em biomoléculas, mecanismo este associado à fisiopatologia da DAC. OBJETIVOS: Verificar a relação entre o índice de apnéia hipopnéia (IAH) e a presença de DAC. Verificar a associação entre IAH, DAC e a atividade das enzimas antioxidantes: SOD, CAT, GPx e antioxidantes não enzimáticos, ácido úrico e vitamina C. Avaliar a relação entre IAH, DAC e os produtos de danos oxidativos em lipídios, proteínas. Entre os marcadores de estresse oxidativo identificar preditores para DAC. MATERIAIS E MÉTODOS: Estudo transversal. Entre junho de 2007 e maio de 2008 na Hemodinâmica do Hospital de Clínicas de Porto Alegre, triamos consecutivamente 519 indivíduos encaminhados para angiografia diagnóstica ou terapêutica. Incluímos 14 pacientes com DAC (≥ 50% diminuição do lúmen da coronária) e 30 controles com < 50% de obstrução. O IAH foi mensurado por meio de polissonografia portátil. Verificamos presença de DAC através da angiografia coronariana. A quantificação dos grupos carbonil no hemolisado e no plasma e as atividades das enzimas antioxidantes SOD, CAT e GPx foram verificadas por método espectrofotométrico. Mensuramos malondialdeído (MDA) e vitamina C por cromatografia líquida de alta eficiência. RESULTADOS: Este é o primeiro trabalho que evidencia correlação entre IAH e o aumento de carbonilação de proteínas eritrocitárias. Além disso, os resultados obtidos mostram que os indivíduos portadores de DAC apresentam níveis maiores de grupos carbonil no hemolisado quando comparados aos indivíduos controles. Em um modelo de regressão multivariado ajustado para idade, sexo e índice de massa corporal, buscando verificar preditores para DAC, verificamos que o aumento de uma unidade de carbonil aumenta 1,7% o risco para desenvolvimento de DAC, já uma unidade do IAH aumenta em 3,9% o risco de desenvolvimento de DAC. Não foi encontrada correlação entre IAH e os marcadores MDA, carbonil no plasma e os antioxidantes: SOD, CAT, GPx vitamina C e ácido úrico. Não verificamos correlação entre DAC e os marcadores MDA, carbonil no plasma e entre os antioxidantes SOD, CAT , GPx e ácido úrico. Pacientes com CAD significativa apresentaram níveis menores de vitamina C. Correlação positiva foi observada entre os níveis de vitamina C e a concentração de proteínas carboniladas no plasma. CONCLUSÃO: Foi evidenciado que a carbonilação de proteínas eritrocitárias e o IAH tem importância na fisiopatologia da DAC. Da mesma forma a vitamina C parece ter importância na prevenção da DAC. / INTRODUCTION: Evidences suggest association between Coronary Artery Disease (CAD) and Sleeping Disordered Breathing (SDB), however the mechanism is uncertain. Repetitive episodes of hypoxia and reoxygenation experienced by individuals with SDB lead to an increase of Reactive Oxygen Species (ROS). ROS inside the erythocytes may be scavenging by glutathione peroxidase antioxidants enzymes (GPx), catalase (CAT) and superoxide dismutase (SOD). In the cytoplasm ROS may be inhibited by vitamin C, or uric acid. Oxidative stress is characterized by an unbalance between ROS and antioxidants. These unbalance promotes oxidative damage in biomolecules, this mechanism is associated to the CAD physiopathology . OBJECTIVE: Verify the relation between apnea hypopnea index (AHI) and CAD. Verify association between AHI, CAD and antioxidants enzymes activity: SOD, CAT, GPx and non enzymatic antioxidants, uric acid, and vitamin C. Evalute the relation between AHI, CAD and oxidative damage products in lipids and proteins. Among the oxidative stress markers identify the predictors for CAD. MATERIALS AND METHODS: Cross sectional study. Between June and May 2008 in the hemodinamic ward of Clinicas Hospital of Porto Alegre, we consecutively screened 519 individuals sent for diagnostic or therapeutic angiography. We included 14 cases with CAD (≥ 50% narrowing of coronary lumen) and 30 controls with < 50% narrowing. The AHI was measured by portable polisomnography. We found the presence of CAD through coronary angiography. Carbonyl groups quantification in the hemolysed and plasma and antioxidants enzyme activities of SOD, CAT and GPx were verified by spectophotometric method. Malondyaldeyde (MDA) and vitamin C were measured by HPLC. RESULTS: This work is the first one that shows correlation between AHI and increased erythrocytes protein carbonylation. In the same way evidences that individuals with significant CAD compared to controls present higher levels of carbonyl groups in the hemolysates. In a multivaried regression model adjusted to age, gender and body mass index to verify predictors for CAD, we verified that the carbonyl unit increased 1.7% the risk for development of CAD, while one unit of IAH increased in 3.9% the risk to develop CAD. We did not find correlation between AHI and the markers MDA, plasma carbonyl and the antioxidants: SOD, CAT, GPx vitamin C and uric acid. We didn’t verify correlation between CAD and the markers MDA, plasma carbonyl and the others antioxidants SOD, CAT , GPx and uric acid. Patients with significant CAD had lower levels of vitamin C. Positive correlation was observed between vitamin C and erythrocyte carbonyl concentration. CONCLUSION: We evidenced that erythrocytes protein carbonylation and AHI are important in the physiopathology of CAD. In the same way vitamin C appears important factor in CAD prevention.
|
192 |
Efeito da ingestão de grãos processados de quinoa por pacientes coronariopatas dislipêmicosSilva, Vanessa Oliveira 01 December 2015 (has links)
Submitted by Fabíola Silva (fabiola.silva@famerp.br) on 2016-06-21T17:35:47Z
No. of bitstreams: 1
vanessaoliveirasilva_dissert.pdf: 429106 bytes, checksum: 44bf78bbec8e150eef1119e341151324 (MD5) / Made available in DSpace on 2016-06-21T17:35:47Z (GMT). No. of bitstreams: 1
vanessaoliveirasilva_dissert.pdf: 429106 bytes, checksum: 44bf78bbec8e150eef1119e341151324 (MD5)
Previous issue date: 2015-12-01 / Introduction: Quinoa (Chenopodium quinoa Willd) is a gluten-free pseudocereal with high biological value protein, low glycemic carbohydrates, phytosterols and omega 3 and 6 fatty acids. It originates from the Andes, where it has been consumed for thousands of years.The aim of this study was to determine the rates of outpatient serum lipids in coronary patients after ingestion of processed grain quinoa.This is a prospective study of twenty-seven outpatients 48-70 years of age (64.0 ± 8.4 years) who were treated for an average of 120– 200 days.Blood samples were collected before and after consumption of the cereal to determine the dyslipidemic profile of the group and the exams were attended.The results showed a positive effect of the use of quinoa once it has been observed a significant reduction in total cholesterol levels (P = 0.0008), triglycerides (P = 0.001) and LDL-c (p = 0.008). We conclude that the use of quinoa in the diet can be considered beneficial in the prevention and treatment of risk factors of cardiovascular diseases that are among the leading causes of death in the globalized world. / Introdução: A quinoa (Chenopodium quinoa Willd) é um pseudocereal isento de glúten, com proteína de alto valor biológico, carboidratos de baixo índice glicêmico, fitosteróis e ácidos graxos ômega 3 e 6. É originária dos Andes, onde vem sendo consumida há milhares de anos. O objetivo deste trabalho foi verificar as taxas de lipídeos séricos em pacientes coronariopatas ambulatoriais após a ingestão de grãos processados de quinoa. Trata-se de um estudo prospectivo com vinte e sete pacientes com 48 a 70 anos de idade (64,0 ± 8,4 anos), que foram tratados por 120 a 200 dias. As amostras de sangue foram coletadas antes e após o consumo do cereal para determinar o perfil lipidêmico do grupo e os exames foram acompanhados. Os resultados mostraram efeitos positivos do uso da quinoa já que se observou redução significante nos valores de colesterol total (P=0,0008), triglicérides (P=0,001) e LDL-c (P=0,008). Conclui-se que o uso da quinoa na alimentação pode ser considerado benéfico na prevenção e controle de fatores de risco de doenças cardiovasculares (DC) que estão entre as principais causas de morte no mundo globalizado.
|
193 |
Efeitos da associação de sinvastatina e ezetimiba na cinética de quilomícrons artificiais em pacientes portadores de doença arterial coronária estável / Favourable effects of ezetimibe alone or in association with simvastatin on the removal from plasma of chylomicrons in coronary heart disease subjectOtávio Celeste Mangili 04 September 2012 (has links)
FINALIDADE: Defeitos na depuração plasmática de quilomícrons e seus remanescentes (QM) predispõem à doença arterial coronária (DAC). QM ligam-se a seus receptores hepáticos específicos (RLP) e aos receptores de LDL (LDL-r). As estatinas reduzem o LDL-colesterol (LDL-C) e melhoram a depuração plasmática de QM, aumentando a expressão hepática do LDL-r. A ezetimiba (EZE), um bloqueador da absorção do colesterol, também aumenta a expressão de LDL-r nos seres humanos. Este estudo avaliou os efeitos isolados da EZE na depuração plasmatica de QM artificial em pacientes DAC. Também foram testados os efeitos da associação da sinvastatina em dose baixa com EZE em comparação com a máxima dose de sinvastatina sobre depuração plasmática de QM. MÉTODOS: 25 pacientes com DAC estável (idade 61 ± 5 anos), após um período de seis semanas de washout de estatinas, foram randomizados para um ou outro tratamento com 10 mg EZE (grupo 1, n = 13) ou sinvastatina 20 mg (grupo 2, n = 12). Os pacientes evoluíram para 10mg + 20mg de sinvastatina com EZE ou sinvastatina 80 mg, respectivamente. Os estudos cinéticos foram realizados no início e após 6 e 12 semanas de cada braço do tratamento. A emulsão lipídica de QM marcada com 14C-CE (que mede a remoção QM e remanescente) e 3H-TG (que mede a lipólise de QM) foi injetada e amostras de sangue foram coletadas durante 60 minutos para determinar taxas de remoção fracionária de radioisótopos (TFR) por análise compartimental. As comparações foram feitas por analise de medidas repetidas (ANOVA). RESULTADOS: Não houve diferenças nas características clínicas e laboratoriais entre os grupos. As TFR de 14C-CE (1/min) no grupo 1 foram 0,005 ± 0,004, 0,011 ± 0,007 e 0,018 ± 0,004 e no grupo 2 foram 0,004 ± 0,002, 0,011 ± 0,008 e 0,019 ± 0,007, respectivamente, à admissão, 6 e 12 semanas ( p <0,05 e ns, respectivamente, para comparações de tempo e grupo). As TFR de 3H-TG (1/min) no grupo 1 foram de 0,017 ± 0,01, 0,024 ± 0,011 e 0,042 ± 0,013 e no grupo 2 foi de 0,01 ± 0,016, 0,022 ± 0,009 e 0,037 ± 0,011, respectivamente, no início do estudo, 6 e 12 semanas ( p <0,05 e ns, respectivamente, para comparações de tempo e grupo). Mudanças semelhantes também foram encontradas para o LDL-C (mg/dL): 142 ± 22,113 ± 19, 74 ± 17 para grupo1 e 119 ± 22, 92 ± 15 e 72 ± 15 para o grupo 2, respectivamente, na admissão, 6 e 12 semanas (p <0,05 para o tempo e ns para o grupo). CONCLUSÃO: EZE isolada aumentou a remoção do plasma de QM e remanescentes e a associação com a sinvastatina aumentou os seus efeitos. A sinvastatina em dose baixa associada à EZE apresentou efeitos favoráveis semelhantes tanto na depuração plasmática de QM quanto na redução de LDL-C em comparação com 80mg de sinvastatina / PURPOSE: Defects on plasma clearance of chylomicrons and their remnants (CM) predispose to coronary heart disease (CHD). CM bind both to their specific liver receptors (LRP) and to the LDL receptors (LDL-r). Statins reduce LDL-cholesterol (LDL-C) and improve the plasma clearance of CM by increasing the expression of hepatic LDL-r. Ezetimibe (EZE), a cholesterol absorption blocker, also increases LDL-r expression in humans. This study evaluated the isolated effects of EZE on the plasma clearance of artificial CM in CHD subjects. We also tested the effects of the association of low dose simvastatin with EZE in comparison with maximal simvastatin dose upon CM plasma clearance. METHODS: 25 stable CHD patients (age 61 ± 5 years, 98%men) after a 6 week statin washout period were randomized for either treatment with EZE 10 mg (group 1, n= 13) or simvastatin 20 mg (group 2 n=12). Patients were progressed to 10mg EZE+ simvastatin 20mg or simvastatin 80 mg, respectively. Kinetic studies were done at baseline and after 6 and 12 weeks of each treatment arm. The CM emulsion labelled with 14C-CE (that measures CM and remnant removal) and 3H-TG (that measures CM lipolysis) was injected and blood samples were collected during 60 minutes to determine radioisotopes fractional catabolic rates (FCR) by compartmental analysis. Comparisons were made repeated measurements ANOVA. RESULTS: There were no differences in clinical and laboratory characteristics between the groups. The 14C-CE FCR (1/min) in group 1 were 0.005±0.004, 0.011±0.007 and 0.018±0.004 and in group 2 were 0.004±0.002, 0.011±0.008 and 0.019±0.007 respectively at baseline, 6 and 12 weeks (p<0.05 and n.s respectively for time and group comparisons). The 3H-TG FCR (1/min) in group 1 were 0.017±0.01, 0.024±0.011 and 0.042±0.013 and in group 2 were 0.01± 0.016, 0.022±0.009 and 0.037±0.011 respectively at baseline, 6 and 12 weeks (p <0.05 and n.s respectively for time and group comparisons). Similar changes were also found for LDL-C (mg/dL):142 ± 22,113 ± 19, 74 ± 17 for group1 and 119 ± 22, 92 ± 15, and 72 ± 15 for group 2 respectively at baseline, 6 and 12 weeks (p<0.05 for time and n.s. for group). CONCLUSION: EZE alone increased the removal from plasma of CM and remnants, the association with simvastatin increased its effects. The low dose simvastatin associated with EZE showed similar favourable effects in both CM plasma clearance and LDL-C in comparison with 80 mg simvastatin
|
194 |
Efeitos Cardiovasculares da anestesia local com vasoconstritor durante exodontia convencional em coronariopatas / Cardiovascular effects of local anesthesia with vasoconstrictor agents during conventional dental extractions in patients with coronary artery diseaseValéria Cristina Leão de Souza Conrado 07 December 2005 (has links)
Os pacientes portadores de afecções ateroscleróticas das artérias coronárias, que necessitam tratamento odontológico sob anestesia local com vasoconstritor, constituem um grupo especial de manejo por múltiplos aspectos. Trata-se de doença que pode apresentar, nestas circunstâncias, complicações com potencial de gravidade como: arritmias, angina instável e até mesmo infarto agudo do miocárdio. O cirurgião-dentista diante destes riscos deve conhecer as soluções anestésicas, bem como as interações medicamentosas e eventuais repercussões cardiovasculares. Objetivos: avaliar a ocorrência das seguintes variáveis detectoras de isquemia miocárdica durante ou após o tratamento odontológico:1) alterações do segmento ST avaliadas pelo sistema Holter; hipocontratilidade do ventrículo esquerdo pela Doppler-ecocardiografia e elevação dos marcadores bioquímicos; 2) precordialgia, arritmias e insuficiência mitral. Métodos: Os pacientes coronariopatas eram submetidos à exodontia sob anestesia local com ou sem vasoconstritor, divididos em dois grupos (sorteio por envelope). Em todos praticava-se monitoração eletrocardiográfica com Holter por 24 horas; Doppler-ecocardiograma antes e após intervenção odontológica e dosavam-se os marcadores bioquímicos antes e 24 horas após a exodontia (CKMB massa, CKMB atividade e troponina T). Aferia-se, também, a freqüência cardíaca e a pressão arterial nas fases pré, pós-anestesia e pós-exodontia. A Doppler-ecocardiografia avaliava a contratilidade segmentar do ventrículo esquerdo e a eventual ocorrência de insuficiência mitral. Resultados: 54 pacientes com doença coronária comprovada por cinecoronariografia e com indicação de extração dentária foram incluídos no estudo, no período de maio de 2004 a maio de 2005. Os casos foram divididos em dois grupos: grupo I com 27 pacientes tratados sob anestesia local com vasoconstritor e grupo II, 27 casos sem vasoconstritor. A média das idades no grupo I foi 58 (DP 7,98) anos e no grupo II de 55 anos (DP 8,57); 59,3 por cento eram do sexo masculino no grupo I e 66,7 por cento no grupo II; 66,6 por cento apresentaram infarto do miocárdio prévio com ou sem supradesnivelamento do segmento ST no grupo I e 77,7 por cento no grupo II. No grupo I a média de dentes extraídos foi de 1,6 dentes por paciente (DP 0,96) e 1,8 dentes por paciente (DP 1,21) no grupo II e a média de tubetes anestésicos por paciente no grupo I foi 1,5 tubetes (DP 0,87) e 1,8 tubetes (DP 0,79) no grupo II. Três pacientes do grupo I apresentaram depressão do segmento ST (1,0 mm), durante a aplicação da anestesia, e em nenhum deles verificou-se presença de isquemia avaliada pelos outros métodos; dois outros pacientes do mesmo grupo I tiveram elevação da CKMB massa. No estudo não se observou ocorrência ou agravamento de hipocontratilidade segmentar do ventrículo esquerdo, precordialgia, arritmias ou insuficiência mitral. Conclusão: Exodontia praticada sob uso de anestesia com epinefrina 1:100.000 não implica em riscos isquêmicos adicionais, uma vez que realizada com boa técnica anestésica e manutenção do tratamento farmacológico prescrito pelo cardiologista / Background: Patients with coronary artery disease, needing odontological treatment under local anesthesia with vasoconstrictor agents, comprised a special group to manage because of multiple aspects. In this situation, cardiovascular disease can be presented with serious complications, such as: arrhythmias, unstable angina and even acute myocardial infarction. The dental practioner facing these controversies must know the anesthesical solutions, drug interactions and possible cardiovascular repercussions. Objectives: To evaluate the occurrence of myocardial ischemic parameters during or after the odontological treatment such as: 1) ST-segment changes evaluated by Holter system, left ventricular hypocontractility by Doppler-echocardiography and serium biomarkers elevation; 2) angina pectoris, arrhythmias and mitral insufficiency. Methods: The coronary patients were submitted to dental extractions under local anesthesia with or without vasoconstrictor and were divided into two groups according to randomization. All patients were monitor with Holter throughout 24 hours; Doppler-echocardiograms were done before and after odontological interventions and the biochemical markers were measured before and 24 hours after the dental extractions (CKMB mass, CKMB activity and Troponin T). Besides that, cardiac rate and blood pressure were also measured pre and post-anesthesia and post-dental extractions. The Doppler-echocardiograms were done to evaluate the left ventricular contractility and possible mitral insufficiency. Results: Between May 2004 and May 2005, fifty-four patients with coronary artery disease and with indication for dental extraction were included in this study. Patients were equally divided into two groups: 27 patients treated with local anesthesia with vasoconstrictor (group I) and 27 patients without vasoconstrictor (group II). The mean age of group I was 58 years old (SD 7.98) and of group 2 was 55 years old (SD 8.57); male gender was 59.3 per cent in group I and 66.7 per cent in group II; 66.6 per cent had previous myocardial infarction with or without ST elevation in group I and 77.7 per cent in group II. In group I the mean dental extraction was 1.6 teeth per patient (SD 0.96) and 1.8 teeth per patient (SD 1.21) in group II. The mean number of anesthesic tubes per patient were 1.5 tubes (SD 0.87) and 1.8 tubes (SD 0.79) for groups I and II, respectively. Three patients from group I had ST-segment depression (1.0 mm) during the anesthesia application, and in none of these patients were observed any other ischemic method. Two other patients from group I had CKMB mass elevation. In none of the patients was observed left ventricular hypocontractility, angina pectoris, arrhythmias or mitral insufficiency. Conclusions: The dental extraction performed under the use of anesthesia with epinephrine 1:100,000 do not cause additional ischemical risks, since it is done with good anesthesical technique and maintenance of the pharmacological treatment prescribed by the cardiologist
|
195 |
Papel das estatinas na lesão miocárdica e nos marcadores inflamatórios em pacientes submetidos a implante eletivo de stent coronário / Effec of statin therapy on inflammation and myocardial injury in satable coronary artery disease patients submitted to coronary stent implantationtGreque, Gilmar Valdir 13 December 2012 (has links)
Introdução. A elevação dos marcadores inflamatórios e de necrose miocárdica, após intervenção coronária percutânea, pode interferir nos resultados clínicos. No entanto, pouco se conhece sobre a terapia com estatinas pré-procedimento na redução destes marcadores em pacientes estáveis de baixo risco. Objetivo. Avaliar se o uso de estatina, antes do implante eletivo de stent coronário (ISC), reduz os níveis plasmáticos de marcadores inflamatórios e de necrose miocárdica, em pacientes com doença arterial coronária (DAC), estáveis e de baixo risco. Métodos. Neste estudo observacional prospectivo, 100 pacientes (n=50 em uso de estatina vs n=50 sem uso de estatina) com DAC estável foram submetidos à implante eletivo de stent coronário. Marcadores inflamatórios (proteína C reativa [PCR], interleucina[IL] -6, fator de necrose tumoral- e matrix metaloproteinase-9) e marcadores de necrose miocárdica (troponina I e CK-MB ) foram dosados antes e 24 horas após o implante eletivo de stent coronário. Resultados. Todos os pacientes apresentaram um aumento significativo de PCR e IL-6, após ISC. No entanto, esse aumento foi anulado em pacientes que faziam uso de estatina antes de ISC em relação àqueles que não tomavam estatina: 75% vs 150% (p <0,001) e 192% vs 300% (p <0,01) respectivamente. Os outros marcadores pró-inflamatórios foram semelhantes para os dois grupos de pacientes. Troponina I e CK-MB não se alterou, após ISC, independentemente, da terapia com estatina anterior ou não. Conclusão. O pré-tratamento com estatina reduz a magnitude da inflamação após ISC, demonstrada por aumentos significativamente menores de PCR e IL-6, em pacientes com DAC, estável e de baixo risco. Lesão miocárdica periprocedimento foi irrelevante e não foi afetada pela terapia com estatina pré-procedimento nesta população / Background. The elevation of markers of inflammatory and myocardial necrosis after percutaneous coronary intervention may interfere on clinical outcome. However, little is known concerning preprocedural statin therapy on the reduction of these markers in stable patients at low-risk. Objective. To evaluate if statin therapy prior to elective coronary stent implantation (CSI) reduces the plasma levels of markers inflammatory and myocardial necrosis in patients with low-risk stable coronary artery disease (CAD). Methods. In this prospective, observational study, 100 patients (n=50 on statin therapy vs n=50 not on statin) with stable CAD underwent elective CSI. Inflammatory (C-reactive protein [CRP], interleukin [IL]-6, tumor necrosis factor-a and matrix metalloproteinase-9) and myocardial necrosis markers (troponin I and CK-MB) were determined before and 24 hours after CSI. Results. All patients presented a significant increase of CRP and IL-6 after CSI. However, this increase was blunted in patients on statin therapy prior to CSI than those without statin therapy: 75% vs 150% (p<0.001), and 192% vs 300% (p<0.01), respectively for PCR and IL-6. The other pro-inflammatory markers were not affected in both sets of patients. Troponin I and CK-MB did not change after CSI regardless of previous statin therapy or not. Conclusions. Previous treatment with statins reduces the magnitude of procedural inflammation, denoted by markedly lower increases of CRP and IL-6 levels, in elective CSI on stable CAD patients. Periprocedural myocardial injury was not significant in this population
|
196 |
Efeitos da associação de sinvastatina e ezetimiba na cinética de quilomícrons artificiais em pacientes portadores de doença arterial coronária estável / Favourable effects of ezetimibe alone or in association with simvastatin on the removal from plasma of chylomicrons in coronary heart disease subjectMangili, Otávio Celeste 04 September 2012 (has links)
FINALIDADE: Defeitos na depuração plasmática de quilomícrons e seus remanescentes (QM) predispõem à doença arterial coronária (DAC). QM ligam-se a seus receptores hepáticos específicos (RLP) e aos receptores de LDL (LDL-r). As estatinas reduzem o LDL-colesterol (LDL-C) e melhoram a depuração plasmática de QM, aumentando a expressão hepática do LDL-r. A ezetimiba (EZE), um bloqueador da absorção do colesterol, também aumenta a expressão de LDL-r nos seres humanos. Este estudo avaliou os efeitos isolados da EZE na depuração plasmatica de QM artificial em pacientes DAC. Também foram testados os efeitos da associação da sinvastatina em dose baixa com EZE em comparação com a máxima dose de sinvastatina sobre depuração plasmática de QM. MÉTODOS: 25 pacientes com DAC estável (idade 61 ± 5 anos), após um período de seis semanas de washout de estatinas, foram randomizados para um ou outro tratamento com 10 mg EZE (grupo 1, n = 13) ou sinvastatina 20 mg (grupo 2, n = 12). Os pacientes evoluíram para 10mg + 20mg de sinvastatina com EZE ou sinvastatina 80 mg, respectivamente. Os estudos cinéticos foram realizados no início e após 6 e 12 semanas de cada braço do tratamento. A emulsão lipídica de QM marcada com 14C-CE (que mede a remoção QM e remanescente) e 3H-TG (que mede a lipólise de QM) foi injetada e amostras de sangue foram coletadas durante 60 minutos para determinar taxas de remoção fracionária de radioisótopos (TFR) por análise compartimental. As comparações foram feitas por analise de medidas repetidas (ANOVA). RESULTADOS: Não houve diferenças nas características clínicas e laboratoriais entre os grupos. As TFR de 14C-CE (1/min) no grupo 1 foram 0,005 ± 0,004, 0,011 ± 0,007 e 0,018 ± 0,004 e no grupo 2 foram 0,004 ± 0,002, 0,011 ± 0,008 e 0,019 ± 0,007, respectivamente, à admissão, 6 e 12 semanas ( p <0,05 e ns, respectivamente, para comparações de tempo e grupo). As TFR de 3H-TG (1/min) no grupo 1 foram de 0,017 ± 0,01, 0,024 ± 0,011 e 0,042 ± 0,013 e no grupo 2 foi de 0,01 ± 0,016, 0,022 ± 0,009 e 0,037 ± 0,011, respectivamente, no início do estudo, 6 e 12 semanas ( p <0,05 e ns, respectivamente, para comparações de tempo e grupo). Mudanças semelhantes também foram encontradas para o LDL-C (mg/dL): 142 ± 22,113 ± 19, 74 ± 17 para grupo1 e 119 ± 22, 92 ± 15 e 72 ± 15 para o grupo 2, respectivamente, na admissão, 6 e 12 semanas (p <0,05 para o tempo e ns para o grupo). CONCLUSÃO: EZE isolada aumentou a remoção do plasma de QM e remanescentes e a associação com a sinvastatina aumentou os seus efeitos. A sinvastatina em dose baixa associada à EZE apresentou efeitos favoráveis semelhantes tanto na depuração plasmática de QM quanto na redução de LDL-C em comparação com 80mg de sinvastatina / PURPOSE: Defects on plasma clearance of chylomicrons and their remnants (CM) predispose to coronary heart disease (CHD). CM bind both to their specific liver receptors (LRP) and to the LDL receptors (LDL-r). Statins reduce LDL-cholesterol (LDL-C) and improve the plasma clearance of CM by increasing the expression of hepatic LDL-r. Ezetimibe (EZE), a cholesterol absorption blocker, also increases LDL-r expression in humans. This study evaluated the isolated effects of EZE on the plasma clearance of artificial CM in CHD subjects. We also tested the effects of the association of low dose simvastatin with EZE in comparison with maximal simvastatin dose upon CM plasma clearance. METHODS: 25 stable CHD patients (age 61 ± 5 years, 98%men) after a 6 week statin washout period were randomized for either treatment with EZE 10 mg (group 1, n= 13) or simvastatin 20 mg (group 2 n=12). Patients were progressed to 10mg EZE+ simvastatin 20mg or simvastatin 80 mg, respectively. Kinetic studies were done at baseline and after 6 and 12 weeks of each treatment arm. The CM emulsion labelled with 14C-CE (that measures CM and remnant removal) and 3H-TG (that measures CM lipolysis) was injected and blood samples were collected during 60 minutes to determine radioisotopes fractional catabolic rates (FCR) by compartmental analysis. Comparisons were made repeated measurements ANOVA. RESULTS: There were no differences in clinical and laboratory characteristics between the groups. The 14C-CE FCR (1/min) in group 1 were 0.005±0.004, 0.011±0.007 and 0.018±0.004 and in group 2 were 0.004±0.002, 0.011±0.008 and 0.019±0.007 respectively at baseline, 6 and 12 weeks (p<0.05 and n.s respectively for time and group comparisons). The 3H-TG FCR (1/min) in group 1 were 0.017±0.01, 0.024±0.011 and 0.042±0.013 and in group 2 were 0.01± 0.016, 0.022±0.009 and 0.037±0.011 respectively at baseline, 6 and 12 weeks (p <0.05 and n.s respectively for time and group comparisons). Similar changes were also found for LDL-C (mg/dL):142 ± 22,113 ± 19, 74 ± 17 for group1 and 119 ± 22, 92 ± 15, and 72 ± 15 for group 2 respectively at baseline, 6 and 12 weeks (p<0.05 for time and n.s. for group). CONCLUSION: EZE alone increased the removal from plasma of CM and remnants, the association with simvastatin increased its effects. The low dose simvastatin associated with EZE showed similar favourable effects in both CM plasma clearance and LDL-C in comparison with 80 mg simvastatin
|
197 |
Depression and Heart Rate Variability in Patients with Coronary Artery DiseaseSaunders, Roger D. (Roger Dean) 12 1900 (has links)
Depression is an independent risk factor for morbidity and mortality in patients with coronary artery disease (CAD). Altered autonomic nervous system (ANS) activity, a common feature of depression, is also a risk factor for cardiac events in patients with CAD. Heart rate variability (HRV) reflects ANS activity, and reduced HRV predicts morbidity in cardiac populations. The purpose of this study was to determine whether differences in HRV exist between depressed and nondepressed patients with CAD. Twenty-one depressed inpatients, with angiographically documented CAD were retrospectively matched to 21 nondepressed CAD patients by sex, age, and smoking status. Demographic, medical, psychological interview data, and 24-hour ECG recordings were obtained. Depressed subjects had significantly lower HRV, or trends toward lower HRV, than nondepressed subjects, even after controlling for severity of CAD. Subject groups did not differ on left ventricular ejection fraction, history of myocardial infarction, or any other relevant medical variable assessed. These results suggest that depression is associated with decreased HRV in patients with CAD, and may help to explain the increased rates of cardiac events observed in CAD patients with depression.
|
198 |
Geographic and Individual Correlates of Subclinical Atherosclerosis in Asymptomatic Rural Appalachian PopulationMamudu, Hadii M., Jones, Antwan, Paul, Timir, Subedi, Pooja, Wang, Liang, Alamian, Arsham, Alamin, Ali E., Blackwell, Gerald, Budoff, Matthew 31 August 2017 (has links)
Objective: To examine the association between subclinical atherosclerosis (ascertained as coronary artery calcium; CAC) in asymptomatic individuals in the Central Appalachian region of the United States and individual- and geographic-level factors.
Methods: Data were obtained from participants in CAC screening during 2012 and 2016. CAC score was assessed as CAC=0 (no plaque), 1≤CAC≤99 (mild plaque), 100≤CAC≤399 (moderate plaque), and CAC≥400 (severe plaque). Additionally, data on demographics (age, sex, and race), medical conditions, lifestyle factors, and family history of coronary artery disease (CAD) were obtained. Further, zip codes of place of residence for participants were used to generate geographic-level data. Descriptive statistics were used to estimate the prevalence of CAC, and multinomial logistic regression models were used to delineate significant factors.
Results: Of 1512 participants, 57.6% had CAC>0. The prevalence of mild, moderate, and severe plaques was 31.6%, 16.3%, and 9.7%, respectively. Demographic, medical conditions, lifestyle factors, and family history of CAD were associated with increased risk for subclinical atherosclerosis. Further, the proportion of minority residents significantly increased the risk for severe plaque [RRR=1.06; p-value=0.04] and the proportion of residents on government assistance significantly decreased the risk for mild plaque [RRR=0.93; p-value=0.03].
Conclusion: The results imply that the proportion of minority residents in a geographic area is associated with increased relative risk for subclinical atherosclerosis, while the proportion of residents on government assistance decreased such risk. However, future geographic or neighborhood-level studies with larger sample size are needed to delineate further the consistency of these results in the Central Appalachian population.
|
199 |
CFD study on effect of branch sizes in human coronary arteryShrestha, Liza 01 December 2010 (has links)
Atherosclerosis is a term coined to describe a state in which arterial wall thickens due to the accumulation of fatty materials like cholesterol. Though not completely understood, it is believed to occur due to the accumulation of macrophage white blood cells and promoted by low density lipoprotein. Increase in accumulation of plaque leads to enlargement of arteries as arterial wall tries to remodel itself. But eventually the plaque ruptures, letting out its inner content to blood stream. The ruptured plaque clots and heals and shrinks down as well but leaves behind stenosis - narrowing of cross section. Depending on the degree of stenosis blood supply from the artery to its respective organ could decrease and even get blocked completely. Frequently, as the vulnerable plaques rupture, thrombus formed as such could flow through bloodstream towards smaller vessels and block them, leading to a sudden death of tissues fed by that vessel. If the plaques do not rupture and artery gets enlarged to a great extent then it results in an aneurysm. Such blockage of coronary arteries in heart can lead to myocardial infarction - heart attack, in carotid arteries in brain can lead to what is called a stroke, in peripheral arteries in legs can lead to ulcers, gangrene (death of tissue) and hence loss of leg, in renal arteries can lead to kidney malfunction. The most disturbing fact about atherosclerosis is the inability to detect the disease in preliminary stages. As stated by Miller (2001), most of the times coronary artery disease (CAD) gets diagnosed only after 50-75 percent occlusion of arteries.
|
200 |
Intégration des mouvements physiologiques en tomodensitométrie : estimation, reproduction et influence en imagerie cardiaque / Physiological motion in computed tomography : estimation, reproduction and effect in cardiac imagingGuerra, Rui 10 January 2007 (has links)
Une chaîne de traitement a été mise en place permettant de reproduire des mouvements physiologiques afin d’en étudier l’influence et tester les solutions pour y pallier. Une méthodologie originale, basée sur des acquisitions échographiques « Doppler Tissue Imaging », a permis de quantifier les mouvements tridimensionnels de contraction cardiaque. Ces données ont alors servi à optimiser le placement des fenêtres temporelles d’acquisition/reconstruction, à quantifier la résolution temporelle minimum pour geler le mouvement cardiaque le long de son cycle et de données d’entrées de commande d’une plateforme de mouvement et pour un simulateur informatique. Une étude dynamique menée sur des modélisations de calcifications d’artère coronaire a montré l’influence du mouvement respiratoire et la nécessité de l’intégrer dans le processus d’acquisition. Des premiers algorithmes d’estimation et de correction du mouvement ont également été testés sur des données brutes réelles et simulées. / The new idea presented in this work takes into account patient motion in the acquisition and reconstruction processes. For this work, the complete acquisition system has been developed in order to reproduce physiologic motion, analyse their effect and propose correction methods to reduce image artefacts. A new methodology based on Doppler Tissue Imaging was used to find the motion in three dimensions of several coronary artery segments. Based on these data, optimal temporal windows were defined for reconstruction and an analysis of the ideal temporal window in the heart cycle was proposed. Both motion models were then used the control of a motion platform and as input for computer simulations. A first analysis carried on coronary calcification showed the influence of respiratory motion. Estimation and correction of motions were then performed on CT raw data and simulated motion. This works shows that it is necessary to include motion in the acquisition/reconstruction algorithms in CT.
|
Page generated in 0.0824 seconds