Introdução. A dupla antiagregação plaquetária traz benefícios no tratamento do infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAMSST). Há variabilidade intra e interindividual no uso do clopidogrel e isso influencia no benefício do seu uso nesse grupo de pacientes. O objetivo desta pesquisa foi avaliar os efeitos de novo antiagregantes plaquetários (prasugrel e ticagrelor) administrados na sala de emergência (\"upstream\") sobre o resultado angiográfico da angioplastia primária, levando em conta o fluxo coronariano TIMI, o blush miocárdico e a carga de trombo. Métodos. Foi realizado um ensaio clínico, randomizado, cego, com 131 pacientes admitidos com IAMSST. Todos os pacientes receberam ácido acetilsalicílico (AAS). Os pacientes foram randomizados para receber clopidogrel (n=44), prasugrel (n=41) ou ticagrelor (n=46) como dose de ataque ainda na emergência. Todos os pacientes foram submetidos a aspiração manual de trombos. Ao término do procedimento, o resultado angiográfico foi avaliado quanto ao fluxo TIMI, o blush miocárdico e a carga de trombo. Resultados. O fluxo coronariano TIMI >= 1 antes do procedimento foi observado mais frequentemente com o uso de ticagrelor (n = 10, 21,7%) do que com o clopidogrel (n = 1, 2,3%) e prasugrel (n = 5, 12,2%; p = 0,019). O fluxo TIMI coronária no fim do procedimento não diferiu significativamente entre os grupos (p = 0,101). Melhor resultado no que diz respeito ao blush miocárdico foi observada com prasugrel, que produziu um grau de blush III em 85,4% (n = 35) dos pacientes, em comparação com o clopidogrel (54,5%; n = 24) e ticagrelor (67,4%; n = 31; p = 0,025). A carga de trombo pré-procedimento foi maior no grupo de clopidogrel, em que 97,7% (n = 43) dos casos denotaram carga de trombo grau 4/5, enquanto 87,8% (n = 36) do grupo prasugrel tiveram respostas semelhantes, e 80,4% (n = 37) foram observadas no grupo ticagrelor (p = 0,03). Conclusão. Os novos antiagregantes plaquetários ticagrelor e prasugrel parecem exercer efeito sobre o resultado angiográfico dos pacientes submetidos a angioplastia primária. O uso do ticagrelor propiciou menor carga de trombo e um fluxo TIMI melhor no pré-procedimento e o uso do prasugrel ensejou melhor perfusão miocárdica analisada pelo blush miocárdico. Não houve diferença no fluxo angiográfico TIMI pós procedimento / Introduction. Dual antiplatelet therapy has benefits in the treatment of acute myocardial infarction with ST-segment elevation (STEMI). There is variability intra and inter individual in the use of clopidogrel and this influences the benefit of its use in this group of patients. The objective of this research was to evaluate the angiographic results of Upstream Clopidogrel, Prasugrel, or Ticagrelor For Patients Treated With Primary Angioplasty. Methods. A clinical trial was conducted, randomized, double blind, with 131 patients admitted with STEMI. All patients received acetylsalicylic acid (ASA). Patients were randomized to receive clopidogrel (n = 44), prasugrel (n = 41) or ticagrelor (n = 46) as loading dose even in emergency. All patients were submitted to manual thrombus aspiration. At the end of the procedure, the angiographic result was evaluated for TIMI flow, myocardial blush and thrombus burden. Results. A coronary TIMI flow >= 1 before the percutaneous procedure was observed more frequently with the use of ticagrelor (n=10, 21.7%) than with clopidogrel (n=1, 2.3%) and prasugrel (n=5, 12.2%; p=0.019). The coronary TIMI flow at the end of the procedure did not significantly differ between the groups (p=0.101). A better result with respect to myocardial blush was observed with prasugrel, which yielded a blush grade of III in 85.4% (n=35) of patients, compared with clopidogrel (54.5%; n=24) and ticagrelor (67.4%; n=31; p=0.025). The pre-procedural thrombus burden was found to be of a higher grade in the clopidogrel group, in which 97.7% (n=43) of the cases exhibited thrombus burdens grade 4/5, whereas 87.8% (n=36) of the prasugrel group had similar responses, and 80.4% (n=37) were observed in the ticagrelor group (p=0.03). Conclusions. The novel antiplatelet agents represented by ticagrelor and prasugrel appear to have effect on the angiographic outcome of patients undergoing primary angioplasty. The use of ticagrelor led to a smaller thrombus burden and better TIMI flow at the beginning of the procedure and the use of prasugrel produced a better myocardial perfusion analyzed by myocardial blush. There was no difference in post angioplasty TIMI flow

Nous avons démontré la présence d'apoptose dans le système limbique suivant un infarctus du myocarde. Cette mort cellulaire serait partiellement reliée à l'augmentation de cytokines pro-inflammatoires. Des études démontrent que certains probiotiques ont des effets bénéfiques en diminuant le ratio de cytokines pro/anti-inflammatoires. La prise de probiotiques en prévention, avant l’occlusion d’une artère coronarienne, pourrait-elle diminuer l’apoptose dans le système limbique? Méthodes : La combinaison de probiotiques Lactobacillus helveticus R0052 et Bifidobacterium longum R0175 ou son véhicule fut additionné dans l’eau des rats pendant 28 jours consécutifs. Un infarctus du myocarde fut provoqué par l’occlusion de l’artère coronaire gauche. Après 40 minutes d'occlusion, les régions ischémiques ont été reperfusées pour 72 heures. Les animaux furent sacrifiés et la taille de l'infarctus mesurée. L'amygdale et l'hippocampe furent prélevés pour déterminer l'activité de la caspase-3 (pro-apoptotique), le ratio Bax/Bcl2(proapoptotique/ anti-apoptotique) et l'activité d'Akt (survie cellulaire). Résultats : La taille de l’infarctus n'est pas diminuée dans le groupe probiotique (45% de la région à risque)comparé au groupe placebo. Nos marqueurs d’apoptose démontrent une diminution dans les régions du gyrus denté, de l’amygdale latérale et médiane dans le groupe probiotique par rapport au placebo. L’activité de la caspase-3 et le ratio Bax:Bcl2 furent réduits dans le groupe probiotique de 50% et 40% respectivement (p < 0.05) et phosphorylation d’Akt fut augmentée de 35% (p<0.05). Aucune différence fut observée pour les régions Ca1 et Ca3. Conclusion : La combinaison de probiotiques utilisée réduit l’apoptose dans différentes régions du système limbique 72 heures après un IM. / Apoptosis is observed in limbic system after a myocardial infarction (MI). This cell death is due to the release of pro-inflammatory cytokines. Since probiotics reduce the pro/anti-inflammatory cytokine ratio, we hypothesise that probiotics will lessen apoptosis in the limbic system following MI. Methods: Rats were given probiotics or placebo for 4 consecutive weeks. Rat in the probiotic group received a daily dose of over 1 billion live bacterial cells of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 in combination. A MI was then induced in anesthetised rats by a 40-minute occlusion of the left anterior coronary artery followed by a 72 hours of reperfusion. Infarct size was measured and apoptosis was determined in the amygdala and hippocampus in both groups. Results: Infarct size was not diminished in the probiotic group (45% of the risk area), apoptosis was lessened in the dentate gyrus (DG), the lateral (LA) and medial (MA)amygdala compared to the placebo group. Caspase-3 and Bax/Bcl2 ratio were reduced in the probiotic group by about 50% and 40% respectively. Akt activity was increased by 35% in these regions. No difference was observed in the hippocampus Ca1 and Ca3 regions. Conclusion: This probiotic combination can reduce the apoptosis found in specific regions of the limbic system following a MI, which may have significance for post-MI depression.

Fundação de Apoio a Pesquisa e à Inovação Tecnológica do Estado de Sergipe - FAPITEC/SE / Introduction: The use of reperfusion therapy in the treatment of patients with STEMI, in the shortest time possible, is essential to reduce morbidity and mortality. Previous studies suggest the existence of disparities in the care of patients attended by public and private health services. However, major gaps still exist when this service is focused on patients with STEMI, especially in Brazil. Objective: To estimate disparities in the use of reperfusion therapy for patients diagnosed with STEMI treated in hospitals capable of performing primary angioplasty of public and private in Sergipe. Methods: This is a cross-sectional study with a quantitative approach which used records Study VICTIM. Data were collected in only four hospitals capable of performing primary angioplasty in Sergipe, being one public and three private. We evaluated 301 patients diagnosed with STEMI, 249 of which were treated at public hospitals and 52 in private hospitals from December 2014 until October 2015. Results: On the way to the hospital capable of performing primary angioplasty, 3.2 % of patients treated in public hospitals made use of fibrinolytic, and 1.9% of patients treated in private institutions (p = 1.0). Amongst those patients treated in hospitals with ability to perform primary angioplasty, only 45.3% of treated at the public hospital arrived in ideal time (≤ 12 hours starting from the onset of symptoms), compared with 80.5% of patients treated in private hospitals (p <0.001). The rate of patients who received primary angioplasty in the civil service was significantly lower than the rate observed in private hospitals (39.5% vs 69% respectively, p <0.001). Conclusion: It has been found out that patients with STEMI are not reperfused, both in public and in private services. Moreover, there are significant obstacles related to the logistics of access, in optimum time, to hospitals capable of performing primary angioplasty. This fact is more evident for users of the public network system. Finally, despite the great difficulty of access to such institutions in optimum time, it was observed that a minority of patients in both public and private system, made use of fibrinolytic agents during their commute to the hospital with the ability to perform angioplasty. / Fundamentação: O uso de terapias de reperfusão no tratamento de pacientes com IAMCSST, no menor tempo possível, é essencial para redução da morbimortalidade. Estudos prévios sugerem a existência de disparidades no atendimento a pacientes atendidos por serviços públicos e privados de saúde, porém lacunas importantes ainda existem quando este atendimento está voltado para pacientes com IAMCSST, sobretudo no Brasil. Objetivo: Estimar disparidades no uso de terapias de reperfusão para pacientes diagnosticados com IAMCSST atendidos em hospitais com capacidade para realizar angioplastia primária da rede pública e privada em Sergipe. Métodos: Trata-se de um estudo transversal com abordagem quantitativa que utilizou os registros do Estudo VICTIM. Os dados foram coletados nos quatro únicos hospitais com capacidade para realizar angioplastia primária em Sergipe, sendo um público e três privados. Foram avaliados 301 pacientes diagnosticados com IAMCSST, dos quais 249 foram atendidos pelo hospital público e 52 pelos hospitais privados, no período de dezembro de 2014 até outubro de 2015. Resultados: No trajeto até o hospital com capacidade para realizar angioplastia primária, 3,2% dos pacientes atendidos em hospital público fizeram uso de fibrinolítico, assim como 1,9% dos pacientes atendidos em instituições privadas (p = 1,0). Dos pacientes atendidos nos hospitais com capacidade de realizar angioplastia primária, apenas 45,3% dos atendidos no hospital público chegaram em tempo ótimo (≤ 12 horas contadas a partir do início dos sintomas), em comparação com 80,5% dos pacientes atendidos em hospitais privados (p < 0,001). A taxa de pacientes que utilizaram angioplastia primária no serviço público foi significativamente menor que a taxa observada nos hospitais privados (39,5% vs 69% respectivamente, p < 0,001). Conclusão: Revela-se que um percentual expressivo de pacientes com IAMCSST não é reperfundido, tanto no serviço público como no privado. Ademais, que existem obstáculos importantes relacionados à logística de acesso, em tempo ótimo, a hospitais com capacidade para realizar angioplastia primária, sendo este fato mais evidente para usuários da rede pública. Por último, apesar da grande dificuldade de acesso a tais instituições em tempo ótimo, observou-se que uma minoria dos pacientes, tanto em serviço público como privado, fez uso de agentes fibrinolíticos durante seu trajeto para o hospital com capacidade de realizar angioplastia. Descritores: Infarto do Miocárdio; Reperfusão Miocárdica; Cobertura de Serviços de Saúde; Sistema Único de Saúde; Hospitais Privados.

Plant-derived products have been widely studied for prevention and treatment of several diseases. Substances present in them showing antioxidant activities are of great interest because they are able to minimize cardiac injury associated to reperfusion of ischemic tissues. The cardiac reperfusion injury is a physiopathological phenomenon that can occur in coronary syndromes, during cardiovascular surgery and during angioplasty generating heart tissue lesions. In this context, it becomes important to evaluate the biological effects promoted by plant extracts looking for understand their potential for antioxidant protection in order to prevent cardiac tissue damage. Ethyl acetate fraction (FAE) was obtained from the crude extract of Canavalia rosea leaf. FAE was subjected to a phytochemical screening and some antioxidants molecules were identified. Quantitative evaluation of the antioxidant activity and the ability of FAE to scavenge DPPH radicals was performed. It was found that FAE caused a significant reduction in the amount of this radical (p < 0.001), inhibiting its production in 46.7 ± 3.5% with a EC50 of 20.9 ± 0.3 μg/mL. The index of antioxidant activity (IAA) associated to this fraction was 1.42, considered high (Soler-Rivas et al., 2000; Argolo et al., 2004). The in vitro lipid peroxidation was induced by ferrous sulfate. Different concentrations of FAE reduced the lipid peroxidation induced by this substance. We also have evaluate the electrical and contractile effects of FAE (300 μg/mL) in isolated hearts of rats mounted in Langendorff aortic perfusion system. FAE changed significantly, the electrocardiographic profile, increasing the duration of the following intervals: PRi (from 78.48 to 104.7, n = 5, p<0.05), QTi, (from 30.41 to 41.03, n = 5, p<0.05) as well as the QRS complex (from 17.36 to 25.19, n = 5, p<0.05). Furthermore, it reduced the heart rate (from 128.5 to 87.8, n =5, p<0.05). Studing its contractile effects, we have observed that this fraction promoted reduction of the left intraventricular pressure (PVE) (from 1.68 to 1.17, n = 5, p<0.05) as the contraction speed. Cardioprotective effect of FAE was evaluated by testing its skill to reduce the myocardial injury promoted by reperfusion of the heart tissue. To do that, we have employed enzymatic methods in order to evaluate the oxidative stress and also its action on the tissue contractile activity. Our results showed that the FAE reduced dP/dt maximum measured during systole and diastole. Conversely, it increased the diastolic time and also the PVE. During reperfusion after ischemia FAE significantly improved the heart rate decreasings the Index of Severity of Arrhythmia (ISA). The evaluation of antioxidant effects was performed by TBARS measurements as well as studying the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reductase (GR) activities. It was observed that lipid peroxidation was significantly lowered in hearts previously perfused with FAE, and subjected to protocols of ischemia-reperfusion, when compared with the animal group only infused with the vehicle (control animals). The activities of SOD, GPx and GR was significantly higher in hearts previously perfused with FAE, but CAT activity was lower. Looking at CK we observe that this index was lower in previously perfused by the FAE. With this set of results we can conclude that the FAE improves post-ischemic cardiac function. This may be due to the ability of flavonoids scavengers radicals and/or ability on the FAE induces increased activity of antioxidant enzymes in hearts subjected the injuries resulting from the cardiac reperfusion. / Os produtos derivados de plantas têm sido vastamente estudados para prevenção, cura e tratamento de doenças. Sustâncias neles presentes e que apresentam atividade antioxidante são de grande interesse para a minimização da injúria cardíaca que pode ser provocada pela reperfusão deste tecido. A injúria de reperfusão cardíaca é um fenômeno fisiopatológico ocorrendo nas síndromes coronarianas, nas cirurgias cardiovasculares e nas angioplastias, podendo gerar lesões no tecido cardíaco. Neste contexto, é importante avaliar os efeitos biológicos de derivados de plantas, avaliando o seu potencial antioxidante útil na proteção do tecido cardíaco e na prevenção dos danos causados por diversas doenças cardíacas. Uma fração de acetato de etila (FAE) foi obtida do extrato bruto das folhas de Canavalia rosea. A FAE foi submetida à prospecção fitoquímica tendo sido nela identificados compostos antioxidantes. A avaliação quantitativa da atividade antioxidante desta fração foi realizada estudando sua capacidade de sequestrar o radical livre DPPH . Foi observado que ela promoveu uma redução significativa deste radical (p<0,001), apresentando uma inibição na produção deste radical de 46,7 ± 3,5 % com uma CE50 de 20,9 ± 0,3 μg/mL. O Índice de Atividade Antioxidante (IAA) apresentado pela fração foi de 1,42, considerado forte, dentro da escala proposta por Soler-Rivas et al., (2000) e Argolo et al., (2004). A lipoperoxidação in vitro foi induzida pelo sulfato ferroso. Nas diferentes concentrações testadas, a FAE reduziu significativamente a lipoperoxidação induzida por esta substância. Foram também avaliados os efeitos contráteis e elétricos da FAE (300 μg/mL) em coração isolado de ratos montado em sistema de perfusão aórtica do tipo Langendorff. A FAE alterou de forma significativa o perfil eletrocardiográfico, aumentando a duração do intervalo PR (PRi) (de 78,48 para 104,7, n = 5 , p<0,05), do intervalo QT (QTi) (de 30,41 para 41,03, n = 5, p<0,05) e do complexo QRS (de 17,36 para 25,19, n = 5, p<0,05) e reduzindo a frequência cardíaca (de 128,5 para 87,82, n =5, p<0,05). Na avaliação dos efeitos contráteis, a fração diminuiu a pressão intraventricular esquerda (PVE) (de 1,682 para 1,173, n = 5, p<0,05), bem como a velocidade máxima de contração. O efeito cardioprotetor da FAE foi testado avaliando seu potencial para limitar a injúria tissular provocada pela reperfusão. Para isto, foram empregados métodos enzimáticos a fim de avaliar o estresse oxidativo e também sua ação sobre a atividade contrátil do tecido. Os resultados mostraram que a FAE reduziu significativamente a dP/dt máxima tanto na contração quanto no relaxamento. Ainda mais, ela aumentou o tempo de diástole e a PVE. Na reperfusão pós-isquemia, houve melhora significativa da frequência cardíaca e diminuição do Índice de Severidade da Arritmia (ISA). A avaliação dos efeitos antioxidantes foi feita através da medida da TBARS e da atividade das enzimas superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx) e redutase (GR). Foi observado que a peroxidação lipídica foi significativamente menor nos corações perfundidos previamente com a FAE e depois submetidos à isquemia e à reperfusão do que quando comparados com o grupo perfundido somente com o veículo (animais controle). As atividades da SOD, GPx e GR foram significativamente maiores nos corações perfundidos previamente com a FAE, porém a atividade da CAT foi menor neste grupo. Ao analisarmos a concentração do marcador CK observamos que a mesma apresentou-se menor no grupo perfundido previamente com FAE. Com este conjunto de resultados concluímos que a FAE melhora a função cardíaca pós-isquêmica. Isto pode ter decorrido da habilidade que os flavonoides têm de sequestrar radicais livres e/ou da habilidade da FAE em induzir o aumento da atividade de enzimas antioxidantes nos corações submetidos à injúria decorrente da reperfusão do tecido cardíaco.

Orientador: Orlando Petrucci Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T04:53:27Z (GMT). No. of bitstreams: 1 Vilarinho_KarlosAlexandredeSousa_D.pdf: 8722911 bytes, checksum: 025ab56f3339aaf3caf0958e795ae882 (MD5) Previous issue date: 2012 / Resumo: As lesões de isquemia e reperfusão miocárdica continuam sendo um desafio ao cirurgião cardíaco. A eritropoietina tem demonstrado efeito protetor contra lesões por isquemia e/ou reperfusão em corações adultos. Seu papel em corações neonatais ainda não foi esclarecido. Objetivo: avaliar o uso da eritropoietina em corações neonatais submetidos a isquemia e reperfusão. Material e métodos: suínos neonatos foram divididos em grupos de acordo com o momento da administração da eritropoietina (EPO- administrada três minutos antes da isquemia; EPO24- administrada 24 horas antes da isquemia; Controlenão recebeu eritropoietina) e submetidos a 45 minutos de isquemia miocárdica por oclusão da art. interventricular anterior e 90 minutos de reperfusão e avaliados índices de contratilidade derivados de curvas de volume vs. pressão obtidas por meio de cristais sonomicrométricos e pressão intraventricular. As vias da Akt e ERK ½ foram avaliados por western blot. Resultados: os grupos foram semelhantes na avaliação antes da isquemia. Não observamos diferenças entre os grupos em relação a frequência cardíaca, débito cardíaco e volume sistólico do ventrículo esquerdo. Observamos melhora da elastância máxima no grupo EPO aos 60 e 90 minutos de reperfusão, e melhora do trabalho sistólico prérecrutável e da dP/dt máxima nos dois grupos que receberam eritropoietina ao final da isquemia e durante toda a reperfusão. Não houve diferença entre os grupos nos índices de função diastólica. A eritropoietina promoveu fosforilação da Akt, mas não da ERK, e menor expressão de proteínas pró-apoptóticas. Conclusão: A eritropoietina protegeu a função sistólica do ventrículo esquerdo de corações neonatais submetidos a isquemia e reperfusão. Este resultado foi provavelmente mediado por ativação da via Akt / Abstract: Background: The effect of erythropoietin (EPOT) on neonatal hearts is not well understood. The current hypothesis is that erythropoietin has protective effects against ischemia-reperfusion when administered prior to ischemia induction. Methods: Systolic and diastolic indices, as well as the Akt and extracellular regulated kinase (ERK) signaling pathways, were studied in vivo using a neonatal pig heart model. Regional ischemia was induced for 45 min by ligation of the left anterior descending artery, followed by 90 min of reperfusion. The treatment groups consisted of: 1) untreated controls, 2) treatment with erythropoietin 3 min prior to ischemia, and 3) treatment with erythropoietin 24 h before ischemia. Sophisticated myocardial contractility indices were assessed by pressure/volume loops of the left ventricle. The Akt and ERK pathways were evaluated via western blot. Results: Elastance was found to be higher in the group receiving erythropoietin 3 min prior to ischemia. In addition, preload recruitable stroke work was higher for both groups receiving erythropoietin prior to ischemia when compared to controls. The time constant of the isovolumic relaxation and end diastolic pressure volume relationship did not differ between the three groups after 90 min of reperfusion. Furthermore, erythropoietin treatment enhanced phosphorylation of Akt, but not ERK, and erythropoietin treated animals showed lower levels of apoptosis-related proteins. Conclusions: Erythropoietin had a protective effect on neonatal systolic function after ischemia/reperfusion injury, but no effect on diastolic function. This cardioprotective effect might be mediated by activation of the Akt pathway / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências

L’activité plaquettaire joue un rôle clé dans la physiopathologie de l’infarctus du myocarde avec sus-décalage du segment ST (IDM ST+). La réactivité plaquettaire est augmentée lors d’un IDM ST+, traité par angioplastie primaire ou par fibrinolyse avec succès. La relation entre la réactivité plaquettaire résiduelle après un pré-traitement, la charge athérothrombotique et la qualité de la reperfusion myocardique reste peu décrite dans le cadre des IDM ST+. La tomographie par cohérence optique et celle plus récente par domaine de fréquence offrent une imagerie de haute résolution permettant l’identification et la quantification précise de la charge athérothrombotique intracoronaire (CAT). La CAT résiduelle intra-stent peut aider à mieux comprendre la relation entre la réactivité plaquettaire et la reperfusion. Dans un premier temps, nous avons évalué la précision des tests VerifyNow et PFA en comparaison à l’agrégométrie optique pour la détection de l’hyperréactivité plaquettaire dans le contexte particulier des IDM ST+ traités par fibrinolyse avec succès. Nous avons aussi décrit les caractéristiques de la CAT avant et après angioplastie selon la présence d’une rupture de plaque ou d’une érosion coronaire chez des patients traités par fibrinolyse avec succès. Ensuite, nous avons étudié la relation entre la réactivité plaquettaire résiduelle (en réponse au ticagrelor et à l’aspirine) mesurée par VerifyNow et la reperfusion myocardique chez des patients traités par angioplastie primaire. En parallèle, nous avons décrit la relation entre la reperfusion myocardique et la CAT résiduelle intra-stent dans la même cohorte. / Platelet activity plays a key role in the pathophysiology of ST-segment elevation myocardial infarction (STEMI). Platelet reactivity is enhanced after STEMI treated with primary percutaneous coronary intervention (PCI) or successful thrombolysis. The relationship between residual platelet reactivity after pre-treatment, the atherothrombotic burden and the quality of reperfusion remains poorly described in STEMI. Optical coherence tomography (OCT) and optical frequency domain imaging (OFDI) provide high resolution imaging allowing identification and accurate quantification of intracoronary atherothrombotic burden (ATB). Residual in-stent ATB may help to better understand the relation between platelet reactivity and reperfusion. First, we assessed the accuracy of the point-of-care tests VerifyNow and PFA in comparison to light transmittance aggregometry to detect high on-treatment platelet reactivity (HPR) in the particular setting of STEMI successfully treated with fibrinolysis. We also described the characteristics of ATB before and after PCI according to the underlying presence of rupture or erosion in patients successfully treated with fibrinolysis. Then, we assessed the relationship between residual platelet reactivity (in response to ticagrelor and aspirin) using VerifyNow and myocardial reperfusion in primary PCI patients. In parallel, we studied the relationship between myocardial reperfusion and residual in-stent ATB in the same cohort.

Dissertation (PhD)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Activation of the NO-cGMP pathway is associated with myocardial protection against ischaemia/reperfusion injury. However, high-cholesterol diets alter function of this pathway and these alterations have been implicated in both ischaemic/reperfusion injury and the development of ischaemic heart disease. Little is known about the effects of supplements such as Red Palm Oil (RPO) on the myocardial NO-cGMP-signalling pathway. RPO consists of saturated, mono-unsaturated and poly-unsaturated fatty acids and is rich in antioxidants such as β-carotene and Vitamin E (tocopherols and tocotrienols). The aims of this study were: 1) to determine whether dietary RPO-supplemention protects against ischaemia/reperfusion injury in rats fed a standard rat chow (control) and cholesterol-enriched diets and 2) if so, to investigate possible mechanisms for this protection. Male Long-Evans rats were fed a standard rat chow or a standard rat chow plus cholesterol and/or RPO-supplementation for 6 weeks. Myocardial functional recovery was measured and hearts were freeze-clamped for determination of myocardial phospholipid, cAMP/cGMP concentrations, total myocardial nitric oxide concentrations, lipid hydroperoxide production and superoxide dismutase- and nitric oxide synthase activity in isolated rat hearts subjected to 25 minutes of normothermic total global ischaemia. In addition, the degree of phosphorylation of extracellular signal-regulated kinase (ERK), p38, c-Jun N-terminal protein kinase (JNK) and protein kinase B (PKB/Akt) was investigated. Furthermore, the effect of RPO-supplementation on caspase-3 activation and poly (ADP-ribose) polymerase (PARP)-cleavage in hearts subjected to ischaemia and reperfusion was also investigated. Our data show that dietary RPO-supplementation protects the hearts of rats on a standard rat chow (control) and hypercholesterolaemic diet against ischaemia/reperfusion injury as reflected by improved aortic output recovery. Increased intracellular cardiomyocyte NO concentrations as observed in control hearts supplemented with RPO after 120 minutes hypoxia may contribute to the elevated cGMP concentration and may confer some of the cardioprotection to the ischaemic/reperfused heart. Although improved functional recovery with RPO-supplementation of a high-cholesterol diet was also associated with an increase in intracellular cardiomyocyte NO production after hypoxia compared to the non-hypoxic conditions, it could not be linked to increased NO-cGMP signalling. These data are in agreement with other studies, which showed that high-cholesterol diet impairs NO-cGMP signalling and confirms our hypothesis that elevated cGMP concentrations may not be the only mechanism of protection. We have also shown that RPOsupplementation caused increased phosphorylation of p38 and PKB, reduced phosphorylation of JNK and attenuation of PARP cleavage, which may contribute to the protection of the cell against apoptosis. Based on our results we propose that the myocardial protection offered by RPO-supplementation of rats on a normal and hypercholesterolaemic diet may be associated with either its antioxidant characteristics and/or changes in the fatty acid composition of the myocardium during ischaemia/reperfusion. Furthermore, we demonstrated for the first time that RPO-supplementation protects the isolated perfused working rat heart during reperfusion from ischaemia/reperfusion-induced injury through a MAPK-dependent pathway. / AFRIKAANSE OPSOMMING: Aktivering van die NO-cGMP sein transduksie pad word geassosieer met miokardiale beskerming teen isgemie/herperfusie skade. Hoë cholesterol diëte verander egter die funksie van die pad en hierdie veranderings speel ‘n rol in beide isgemie/herperfusie besering en die ontwikkeling van isgemiese hartsiekte. Daar is egter min inligting beskikbaar oor die uitwerking van aanvullings soos rooi palm olie (RPO) op die miokardiale NO-cGMP sein transduksie pad. RPO bevat versadigde, mono-onversadigde en poli-onversadigde vetsure en is ryk aan anti-oksidante nl. β-karotene en vitamien E (tokoferole en tokotriënole). Die doelwitte van hierdie studie was: 1) om vas te stel of ‘n RPO-aanvulling beskerming bied teen isgemie/herperfusie besering in rotte wat gevoed is met ‘n standaard rotmengsel (kontrole) en cholesterol-verrykte dieet en 2) indien wel, om moontlike meganismes van beskerming te ondersoek. Long-Evans manlike rotte is vir 6 weke gevoer met ‘n standaard rotmengsel of ‘n standaard rotmengsel plus cholesterol en/of RPO-aanvulling. Miokardiale funksionele herstel is gemeet en harte is gevriesklamp vir die bepaling van miokardiale fosfolipied, cAMP/cGMP, totale stikstofoksied, lipied hidroperoksied, superoksied dismutase en stikstofoksied sintase in geïsoleerde rotharte wat vir 25 minute onderwerp was aan normotermiese totale globale isgemie. Hiermee saam is die graad van fosforilering van ekstrasellulêre sein gereguleerde kinase (ERK), p38 mitogeen-geaktiveerde proteïen kinase (p38 MAPK), c-Jun-N-terminale proteïenkinase (JNK) en proteïen kinase B (PKB/Akt) ondersoek, asook kaspase-3 aktivering en poli (ADP-ribose) polimerase (PARP) kliewing in harte blootgestel aan isgemie en herperfusie. Ons resultate toon dat RPO-aanvulling van rotte op ‘n normale en hipercholesterolemiese dieet die hart beskerm soos getoon deur verbeterde herstel van aortiese uitset. Verhoogde intrasellulêre miokardiale NO vlakke in kontrole harte met ‘n RPO-aanvulling wat blootgestel was aan 120 minute hipoksie, mag bygedra het tot die verhoogde cGMP vlakke en beskerming van die hart tydens isgemie en herperfusie. Alhoewel verbeterde funksionele herstel met RPO-aanvulling van ‘n hoë cholesterol dieet ook geassosieer is met ‘n toename in intrasellulêre miokardiale NO produksie ná hipoksiese toestande, kon dit nie verbind word met verhoogde aktivering van die NOcGMP sein transduksie pad nie. Hierdie resultate stem ooreen met ander studies wat aangetoon het dat hoë-cholesterol diëte die NO-cGMP seinpad onderdruk. Hierdie bevinding bevestig ons hipotese dat verhoogde cGMP vlakke moontlik nie die enigste beskermingsmeganisme is nie. Ons resultate het ook gewys dat RPO-aanvulling fosforilering van p38 en PKB/Akt verhoog, fosforilering van JNK verminder en PARP kliewing onderdruk. Dit dui op beskerming van die sel teen apoptose. Ons resultate dui aan dat die miokardiale beskerming wat RPO-dieet aanvulling bied moontlik geassosieer kan word met sy anti-oksidant eienskap en/of veranderinge in die vetsuur samestelling van die miokardium tydens isgemie/herperfusie. Ons het ook vir die eerste keer bewys dat RPO-aanvulling die geïsoleerde geperfuseerde werkende rothart gedurende herperfusie beskerm teen isgemie/herperfusie besering deur die aktivering en/of deaktivering van die MAPK afhanklike pad.

Este trabalho avaliou o efeito de fibroblastos cardíacos (FC) modificados geneticamente para produzir VEGF (vascular endothelial growth factor) e/ou em conjunto com IGF-1(insulin -like growth factor) associados a um biopolímero de fibrina na indução de angiogênese, vasculogênese e melhora de função em miocárdio isquêmico. Em experimentos preliminares demonstramos que 106 FC modificados pelo AdRSVLacZ expressam o transgene na parede livre do ventrículo esquerdo de ratos Lewis por até 45 dias. Primeiro, o tratamento dos diversos grupos foi feito e 7 dias após, os animais foram submetidos à isquemia por 45 minutos seguida de reperfusão. 21 dias depois, a proteína humana VEGF e a densidade capilar apresentaram aumento no grupo VEGF (proteína humana VEGF: 1209,6±11,4 vs. Veículo 123,1±5,2; Célula 104,2±7,4 e Null 73,2±2,4 células positivas/campo, p< 0,01 e densidade capilar: 543,8 ± 52,1 vs. 349,2 ± 0,9, 288± 19,0 e 245 ± 2,6 capilares/mm2, p< 0,01). A imunofluorescência dupla-marcação para detecção de células endoteliais e células musculares lisas apresentou aumento no grupo VEGF sugerindo formação de vasos estruturados (45±3 vs. 10±2, 8±1 e 16±3, p<0,001) e a área de infarto foi reduzida no VEGF vs. VEÍCULO (3,0 ± 1,3% vs. 8,0 ± 0,8%, p< 0,05. Para testar o efeito terapêutico desta intervenção, um segundo estudo foi realizado com os grupos: VEÍCULO= controle, POLÍMERO = biopolímero de fibrina, CÉLULA, NULL, IGF-1, VEGF e IGF-1+VEGF. Os tratamentos foram realizados 24 horas após os animais terem sido submetidos à isquemia por ligadura permanente. Um mês depois, as proteínas humanas VEGF e IGF 1 apresentaram aumento significativo nos grupos VEGF, IGF-1 e IGF-1+VEGF, com *p=0,0001. Da mesma maneira, somente os grupos que receberam VEGF isoladamente ou associados a IGF-1 tiveram aumento do número de capilares e da densidade vascular e redução da porcentagem de colágeno (35,12 ± 7,05 vs. 31,28 ± 5,03 vs. 30,07 ± 6,21 vs. 25,89 ± 2,92 vs. 15,43 ± 2,02* vs. 16,07 ± 1,83%*, *p<0,05, para os grupos Veículo, Polímero, Célula, Null, IGF-1, VEGF, IGF-1+VEGF, respectivamente). Os índices cardíacos basais morfológicos e funcionais permaneceram inalterados na avaliação direta e pelo ECO entre os grupos enquanto que as medidas diretas de função cardíaca sob estresse farmacológico com a fenilefrina mostraram aumentos significativos no trabalho cardíaco e volume sistólico e diminuição na pressão diastólica final somente nos animais que receberam terapia celular que incluía VEGF. Em conjunto, os dados mostram que a terapia celular combinada com o aumento da expressão de fator angiogênico (VEGF) ou em combinação com fator de crescimento (IGF-1) tem efeito benéfico, uma vez que estes fatores estimularam a proliferação capilar e vascular podendo contribuir para o aumento da circulação colateral, reduzindo o tamanho do infarto e promovendo melhora cardíaca funcional. / The effect of modified cardiac fibroblasts (CF) expressing VEGF (vascular endothelial growth factor) and/or IGF-1 (insulin-like growth factor) associated to fibrin biopolymer to induce angiogenesis, vasculogenesis and improve cardiac function in ischemic cardiac tissue was tested. The direct injection of 106 CF genetically modified to express the reporter gene LACZ (AdRSVLACZ) indicated transgene expression up to 45 days. First, all groups were treated and 7 days later the animals were submitted to a 45 min cardiac ischemic injury. Twenty one days later VEGF protein and capillary density increased only in groups that received VEGF the groups: (VEGF protein: 1209.6±11.4 vs. VEHICLE: 123.1±5.2, Cell: 104.2±7.4 and Null: 73.2±2.4 positive cells/field, p< 0.01 and capillary: 543.8 ± 52.1 vs. 349.2 ± 0.9, 288± 19.0 and 245 ± 2.6 capillaries/mm2, p< 0.01). Merged image of immunoassaying for endothelial and smooth muscle cells specific markers, were significantly greater in VEGF group suggesting maturation of newly formed vessels (45±3 vs. 10±2, 8±1 and 16±3, p<0.001) and myocardial scar area was reduced in VEGF vs. VEHICLE (3.0 ± 1.3% vs. 8.0 ± 0.8%, p< 0.05). To test the therapeutic efficacy of this treatment, a second study was performed with groups: VEHICLE= control, POLYMER= fibrin biopolymer, CELL, NULL, IGF-1, VEGF and IGF-1+VEGF. Treatments were performed 24 hs following ligation of the descending coronary artery. After 4 weeks, VEGF and IGF-1 protein increased in IGF-1, VEGF and IGF-1+VEGF groups, p<0.0001. We observed only in VEGF groups an increase in capillary number and vascular density and reduction in myocardial collagen area (35,12 ± 7,05 vs. 31,28 ± 5,03 vs. 30,07 ± 6,21 vs. 25,89 ± 2,92 vs. 15,43 ± 2,02* vs. 16,07 ± 1,83%*, *p<0,05, to groups VEHICLE, POLYMER, CELL, NULL, IGF-1, VEGF, IGF-1+VEGF, respectively). The morphological and functional basal cardiac indices remained unchanged in all groups, however, under pharmacologic stress using phenilephrine, the VEGF groups displayed significant improvement in cardiac work and stroke volume and a reduction in end diastolic pressure. Taken together, these results indicated that cardiac fibroblasts expressing VEGF alone or in combination with IGF-1 can induce agiogenesis and vasculogenesis in ischemic myocardium decreasing myocardial scar area and improving cardiac performance following coronary ligation.

Este trabalho avaliou o efeito de fibroblastos cardíacos (FC) modificados geneticamente para produzir VEGF (vascular endothelial growth factor) e/ou em conjunto com IGF-1(insulin -like growth factor) associados a um biopolímero de fibrina na indução de angiogênese, vasculogênese e melhora de função em miocárdio isquêmico. Em experimentos preliminares demonstramos que 106 FC modificados pelo AdRSVLacZ expressam o transgene na parede livre do ventrículo esquerdo de ratos Lewis por até 45 dias. Primeiro, o tratamento dos diversos grupos foi feito e 7 dias após, os animais foram submetidos à isquemia por 45 minutos seguida de reperfusão. 21 dias depois, a proteína humana VEGF e a densidade capilar apresentaram aumento no grupo VEGF (proteína humana VEGF: 1209,6±11,4 vs. Veículo 123,1±5,2; Célula 104,2±7,4 e Null 73,2±2,4 células positivas/campo, p< 0,01 e densidade capilar: 543,8 ± 52,1 vs. 349,2 ± 0,9, 288± 19,0 e 245 ± 2,6 capilares/mm2, p< 0,01). A imunofluorescência dupla-marcação para detecção de células endoteliais e células musculares lisas apresentou aumento no grupo VEGF sugerindo formação de vasos estruturados (45±3 vs. 10±2, 8±1 e 16±3, p<0,001) e a área de infarto foi reduzida no VEGF vs. VEÍCULO (3,0 ± 1,3% vs. 8,0 ± 0,8%, p< 0,05. Para testar o efeito terapêutico desta intervenção, um segundo estudo foi realizado com os grupos: VEÍCULO= controle, POLÍMERO = biopolímero de fibrina, CÉLULA, NULL, IGF-1, VEGF e IGF-1+VEGF. Os tratamentos foram realizados 24 horas após os animais terem sido submetidos à isquemia por ligadura permanente. Um mês depois, as proteínas humanas VEGF e IGF 1 apresentaram aumento significativo nos grupos VEGF, IGF-1 e IGF-1+VEGF, com *p=0,0001. Da mesma maneira, somente os grupos que receberam VEGF isoladamente ou associados a IGF-1 tiveram aumento do número de capilares e da densidade vascular e redução da porcentagem de colágeno (35,12 ± 7,05 vs. 31,28 ± 5,03 vs. 30,07 ± 6,21 vs. 25,89 ± 2,92 vs. 15,43 ± 2,02* vs. 16,07 ± 1,83%*, *p<0,05, para os grupos Veículo, Polímero, Célula, Null, IGF-1, VEGF, IGF-1+VEGF, respectivamente). Os índices cardíacos basais morfológicos e funcionais permaneceram inalterados na avaliação direta e pelo ECO entre os grupos enquanto que as medidas diretas de função cardíaca sob estresse farmacológico com a fenilefrina mostraram aumentos significativos no trabalho cardíaco e volume sistólico e diminuição na pressão diastólica final somente nos animais que receberam terapia celular que incluía VEGF. Em conjunto, os dados mostram que a terapia celular combinada com o aumento da expressão de fator angiogênico (VEGF) ou em combinação com fator de crescimento (IGF-1) tem efeito benéfico, uma vez que estes fatores estimularam a proliferação capilar e vascular podendo contribuir para o aumento da circulação colateral, reduzindo o tamanho do infarto e promovendo melhora cardíaca funcional. / The effect of modified cardiac fibroblasts (CF) expressing VEGF (vascular endothelial growth factor) and/or IGF-1 (insulin-like growth factor) associated to fibrin biopolymer to induce angiogenesis, vasculogenesis and improve cardiac function in ischemic cardiac tissue was tested. The direct injection of 106 CF genetically modified to express the reporter gene LACZ (AdRSVLACZ) indicated transgene expression up to 45 days. First, all groups were treated and 7 days later the animals were submitted to a 45 min cardiac ischemic injury. Twenty one days later VEGF protein and capillary density increased only in groups that received VEGF the groups: (VEGF protein: 1209.6±11.4 vs. VEHICLE: 123.1±5.2, Cell: 104.2±7.4 and Null: 73.2±2.4 positive cells/field, p< 0.01 and capillary: 543.8 ± 52.1 vs. 349.2 ± 0.9, 288± 19.0 and 245 ± 2.6 capillaries/mm2, p< 0.01). Merged image of immunoassaying for endothelial and smooth muscle cells specific markers, were significantly greater in VEGF group suggesting maturation of newly formed vessels (45±3 vs. 10±2, 8±1 and 16±3, p<0.001) and myocardial scar area was reduced in VEGF vs. VEHICLE (3.0 ± 1.3% vs. 8.0 ± 0.8%, p< 0.05). To test the therapeutic efficacy of this treatment, a second study was performed with groups: VEHICLE= control, POLYMER= fibrin biopolymer, CELL, NULL, IGF-1, VEGF and IGF-1+VEGF. Treatments were performed 24 hs following ligation of the descending coronary artery. After 4 weeks, VEGF and IGF-1 protein increased in IGF-1, VEGF and IGF-1+VEGF groups, p<0.0001. We observed only in VEGF groups an increase in capillary number and vascular density and reduction in myocardial collagen area (35,12 ± 7,05 vs. 31,28 ± 5,03 vs. 30,07 ± 6,21 vs. 25,89 ± 2,92 vs. 15,43 ± 2,02* vs. 16,07 ± 1,83%*, *p<0,05, to groups VEHICLE, POLYMER, CELL, NULL, IGF-1, VEGF, IGF-1+VEGF, respectively). The morphological and functional basal cardiac indices remained unchanged in all groups, however, under pharmacologic stress using phenilephrine, the VEGF groups displayed significant improvement in cardiac work and stroke volume and a reduction in end diastolic pressure. Taken together, these results indicated that cardiac fibroblasts expressing VEGF alone or in combination with IGF-1 can induce agiogenesis and vasculogenesis in ischemic myocardium decreasing myocardial scar area and improving cardiac performance following coronary ligation.

In cardiology, there are different conditions associated with the release of free radicals in some forms of hypoxia, such as ventilatory hypoxia or reduced perfusion. The role of free radicals during hypoxia in cardiology is the key point of our interest. In presented thesis, we have focused on hypoxia-induced pulmonary vasoconstriction and acute myocardial ischemia. Hypoxic pulmonary vasoconstriction (HPV), an important physiological mechanism, is regulated by changes in the production of and interactions among reactive oxygen species (ROS). There is controversy, however, over whether HPV is mediated by an increase or a decrease in ROS production. Also, the role of nitric oxide (NO) in HPV remains unclear. Our results indicate that inhibition of HPV by the superoxide dismutase mimetic tempol does not depend on either NO production or a decrease in basal vascular tone. The effect of three-day fasting on cardiac ischemic tolerance was investigated in another experimental model. Short-term fasting conclusively decreases ROS production. Three-day fasting effectively protected rat hearts against major endpoints of acute ischemia-reperfusion injury. It prevented severe ventricular arrhythmias and reduced the extent of myocardial infarction. These beneficial effects can be linked to altered mitochondrial redox...