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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.
21

The Effects of Transcutaneous Electrical Neurostimulation on Analgesia and Peripheral Perfusion

Schafer, Leah I 01 December 2015 (has links) (PDF)
Peripheral arterial occlusive disease (PAOD) affects 8 to 12 million Americans over the age of 50. As the disease progresses, arterial occlusions arising from atherosclerotic lesions inhibit normal metabolic vasodilation in the peripheries, resulting in limb ischemia and claudication. Pharmacological and surgical treatments currently used to treat both the hemodynamic and pain symptoms associated with PAOD can involve adverse and potentially life-threatening side effects. Thus, there is a need for additional innovative therapies for PAOD. Neurostimulation has a known analgesic effect on both acute and chronic pain. Although the exact mechanisms remain under investigation, local vascular tone may be modulated by neurostimulation in addition to pain modulation. The Gate Control Theory proposes that electrical activation of mechanoreceptive afferent somatosensory nerves, specifically Aβ fibers, inhibits pain signaling to the brain by activating an inhibitory interneuron in the dorsal horn of the spinal cord which dampens signaling from afferent, C type peripheral nociceptor nerves. Interestingly, Aβ fiber activation may also inhibit norepinephrine release from sympathetic nerve terminals on efferent neurons by activating α-2 adrenergic receptors along the same dermatome, resulting in localized vasodilation in both limbs. Ultimately, electrical stimulation may decrease mean blood pressure and increase local blood flow. The focus of this study was to optimize protocols and perform a small scale clinical study to investigate hemodynamic and analgesic responses to neurostimulation during acute ischemia. We hypothesized that ganglial transcutaneous electrical neurostimulation (TENS) and interferential current (IFC) treatments would decrease pain perception and vascular resistance in the periphery in young, healthy subjects. We further hypothesized that IFC may have a greater hyperemic and analgesic effect on acute ischemia than TENS as its current waveform may be more efficient at overcoming skin impedance. Interestingly, we found trends suggesting that TENS and IFC may increase vascular resistance (VR) and have no noticeable analgesic effect, though TENS may have a slightly lower increase in VR associated with an increase in pain. Further work characterizing the hemodynamic effects of different stimulus waveforms is needed to inform future research into possible neuromodulation therapies for ischemic disease.
22

Effects Of Beet Supplements On Cardiovascular Response Using A Noninvasive Blood Pressure Cuff

Hughes, Nicholas M 01 December 2023 (has links) (PDF)
A Calibrated Cuff Plethysmography device was built, tested for verification, and used to experiment on human subjects to measure the cardiovascular response of consuming a beet supplement, specifically looking at arterial compliance and pressure-area curves. Each subject was tested four times. A baseline was measured under normal conditions and after five-minute hyperemia conditions. 10 subjects were given 6 ounces of water mixed with either purple Kool-Aid (control), a SuperBeets supplement, or a SuperBeets Sport supplement and after 45 minutes, measurements were taken undergoing normal and hyperemia conditions once more. The verification testing demonstrated the calibration of the device was effectively able to measure volume changes using a stationary metal pipe and IV bag, showing an average percent error of 3.11%. Data collected during the patient experiment resulted in the expected arterial compliance curves as well as pressure-area curves, when measurements were taken properly, and the subject didn’t move. These tests were able to validate the use of the device for measuring arterial compliance and seeing distinctions between normal and hyperemic conditions. However, many issues were presented and are thoroughly addressed in this paper for future research using the same device.
23

Adequacy of Muscle Blood Flow During Handgrip Exercise

Harper, Allison Jessica January 2009 (has links)
No description available.
24

Función endotelial en deportistas de alta competición

Gutiérrez Sánchez, José Bernardo 20 April 2007 (has links)
El ejercicio físico induce una serie de modificaciones en el aparato cardiovascular, tanto estructurales como funcionales.Mediante pletismografía arterial se analizaron los flujos arteriales en hiperemia reactiva de miembros superiores e inferiores, de grupos comparativos con distintos hábitos de ejercicio (remeros, ciclistas, exciclistas, sedentarios) y estudiamos su relación con marcadores bioquímicos de disfunción endotelial. Observamos que los grupos con antecedente de haber realizado ejercicio y los que realizan activamente ejercicio muestran un aumento sistémico en la vasodiltación reactiva a la isquemia con mayor incremento en la extremidad que tiene mas carga de trabajo físico, estos grupos muestran cambios bioquímicos favorables con disminuciones en los marcadores de disfunción endotelial, permaneciendo en el grupos de exciclistas el efecto protector del estado antioxidante total, sin embargo se observa un aumento de enzima conversora de angiotensina en el grupo de exciclistas y en los grupos deportistas activos. / Physical exercise induces a series of structural as well as functional modifications in the cardiovascular system.By arterial plethysmography, arterial flows in reactive hyperemia of the upper and lower extremities were analyzed in comparative groups with different exercise habits (rowers, cyclists, ex-cyclists, sedentary), and we studied its relation with biochemical markers of endothelial dysfunction and cardiovascular risk. We observed that the groups with a history of having done exercise and those that actively exercise show an increase in reactive vasodilatation to ischemia in the extremity that has the greatest amount of physical work. These groups show favorable biochemical changes with decreases in endothelial dysfunction and cardiovascular risk markers with the protector effect of the total antioxidant state remaining in ex-cyclists; however, there seems to be a tendency to increase angiotensin converting enzyme in the group of ex-cyclists and in active sportsman.
25

Preventing pressure ulcers by assessment of the microcirculation in tissue exposed to pressure

Bergstrand, Sara January 2014 (has links)
The overall aim of this thesis was to combine optical methods into a system with the ability to simultaneously measure blood flow changes at different tissue depths. The goal of such a system was to reveal vascular mechanisms relevant to pressure ulcer etiology under clinically relevant conditions and in relation to the evaluation of pressure-redistribution support surfaces. This thesis consists of four quantitative, cross-sectional studies measuring blood flow responses before, during, and after pressure exposure of the sacral tissue. Two optical methods – photoplethysmography and laser Doppler flowmetry – were combined in a newly developed system that has the ability to discriminate blood flows at different tissue depths. Studies I and II explored blood flow responses at different depths in 17 individuals. In Study I the blood flow was related to tissue thickness and tissue compression during pressure exposure of ≥ 220 mmHg. In Study II, the sacral tissue was loaded with 37.5 mmHg and 50.0 mmHg, and the variation in blood flow was measured. Studies III and IV included 42 healthy individuals < 65 years, 38 healthy individuals ≥ 65 years, and 35 patients ≥ 65 years. Study III included between-subject comparisons of blood flow and pressure between individuals in the three study groups lying in supine positions on a standard hospital mattress. Study IV added within-subject comparisons while the individual was lying on four different types of mattress. The studies explored the vascular phenomena pressure-induced vasodilation (PIV) and reactive hyperemia (RH). The most common blood flow response to tissue exposure in this thesis was PIV, although a decrease in blood flow (a lack of PIV) was observed in some individuals. The patients tended to have higher interface pressure during pressure exposure than the healthy groups but no differences in blood flow responses were seen. Our results showed that pressure levels that are normally considered to be harmless could have a significant effect on the microcirculation in different tissue structures. Differences in individual blood flow responses in terms of PIV and RH were seen, and a larger proportion of individuals lacked these responses in the deeper tissue structures compared to more superficial tissue structures. This thesis identified PIV and RH that are important vascular mechanisms for pressure ulcer development and revealed for the first time that PIV and RH are present at different depths under clinically relevant conditions. The thesis also identified a population of individuals not previously identified who lack both PIV and RH and seem to be particularly vulnerable to pressure exposure. Further, this thesis has added a new perspective to the microcirculation in pressure ulcer etiology in terms of blood flow regulation and endothelial function that are anchored in clinically relevant studies. Finally, the evaluation of pressureredistribution support surfaces in terms of mean blood flow during and after tissue exposure was shown to be unfeasible, but the assessment of PIV and RH could provide a new possibility for measuring individual physiological responses that are known to be related to pressure ulcer development.
26

Reactive Hyperemia as endothelial function determinant using plethysmography methods

Olamaei, Nina 01 1900 (has links)
L’atteinte de la fonction endothéliale représente une phase précoce de l’athérosclérose, un stade où les patients sont généralement asymptomatiques. Il existe donc un intérêt certain à détecter la dysfonction endothéliale. Nous avons développé une technique de mesure des variations de flot artériel au niveau des membres supérieurs, basée sur la spectroscopie proche infrarouge (NIRS). Cette approche permettrait d’étudier le niveau d’atteinte vasculaire et probablement de quantifier le degré de dysfonction endothéliale périphérique lors d’une hyperémie réactive. L'expérience a été exécutée sur deux cohortes de 13 et de 15 patients et a été comparée à la pléthysmographie par jauge de contrainte (SGP) qui est considérée comme une méthode de référence. Par la suite, nous avons caractérisé la réponse endothéliale par modélisation de la courbe hyperémique du flot artériel. Des études préliminaires avaient démontré que la réponse hyperémique adoptait majoritairement une forme bi-modale. Nous avons tenté de séparer les composantes endothéliales-dépendantes et endothéliales-indépendantes de l’hyperémie. La quantification des deux composantes de la réaction hyperémique permet de calculer un indice de la ‘santé’ du système endothélial local. Cet indice est nommé le ηfactor. Les résultats montrent une forte corrélation des mesures de flots entre la technique développée et la méthode de référence (r=0.91). Nous avons conclu que NIRS est une approche précise pour la mesure non-invasive du flot artériel. Nous avons obtenu une bonne répétabilité (ICC = 0.9313) pour le ηfactor indiquant sa robustesse. Cependant des études supplémentaires sont nécessaires pour valider la valeur de diagnostic du facteur défini. Mots clés: hyperémie réactive, réponse myogénique, oxyde nitrique, athérosclérose, spectroscopie proche infrarouge / Atherosclerotic diseases are mainly caused by coronary and peripheral blood vessel disorders. Endothelial dysfunction represents an early phase in these diseases, when patients are generally asymptomatic. We developed a technique, based on near infrared spectroscopy (NIRS), for measurement of arterial blood flow variations in limbs during reactive hyperemia. The technique allows the study of the level of vascular impairment and probably quantifying the level of endothelial dysfunction at peripheral arteries. The experiment was performed on two cohorts of 13 and 15 patients and was compared to strain gauge plethysmography (SGP) which is considered as gold standard. Afterward, we characterized endothelial reaction during reactive hyperemia through blood flow variations by modeling the hyperemic curve. Preliminary studies have shown that the hyperemic response generally adopts a bimodal form. The first peak was attributed to myogenic reaction that is endothelial independent and the second one to local endothelial cells reaction. The quantification of the two hyperemic response components makes it possible to calculate an index of ‘health’ for local endothelial cells, named ηfactor. The results showed a strong correlation (r = 0.91) of blood flow measurements between the developed method and the gold standard. We concluded that NIRS is a precise technique for non-invasive measurement of blood flow. Moreover, we found a high repeatability (ICC = 0.9313) of the ηfactor in repeated measurements indicating its robustness. Nonetheless, more studies are required to validate the diagnosis value of the defined factor. Key words: reactive hyperemia, myogenic response, endothelial dependent vasodilatation, nitric oxide, atherosclerosis, near infrared spectroscopy (NIRS)
27

Avaliação da inflamação miocárdica na doença de Chagas por ressonância magnética cardiovascular / Detection of myocardial inflammation in Chagas\' heart disease by cardiac magnetic resonance

Torreão, Jorge Andion 12 March 2015 (has links)
INTRODUÇÃO: A cardiopatia chagásica (CC) é um importante problema de saúde pública na América do Sul e a patogênese desta doença ainda não é totalmente compreendida, mas a inflamação e a fibrose miocárdica participam de forma central no processo crônico e progressivo de dano miocárdico. Trabalho prévio de nosso grupo demonstrou a capacidade da Ressonância Magnética Cardiovascular (RMC) de identificar precisamente a fibrose miocárdica em pacientes com Doença de Chagas. A RMC demonstrou ser eficaz para avaliar edema miocárdico, como marcador de inflamação, e ser altamente sensível para a detecção de trombos intracavitários, especialmente no ventrículo esquerdo, e em outras patologias, como miocardites e infartos. A avaliação de edema miocárdio pela RMC em pacientes com CC não foi ainda avaliada na literatura. Nosso objetivo foi investigar a presença de edema e fibrose miocárdica nas três formas clínicas da CC, o que julgamos ser de potencial valor diagnóstico e prognóstico. MÉTODOS: Cinquenta e quatro pacientes com doença de chagas foram analisados: 16 pacientes com a forma indeterminada (FI), 17 pacientes com CC-SD e 21 pacientes com CC-CD. Todos os pacientes foram submetidos a exame de RMC em equipamento de 1,5 T, utilizando a sequência de realce tardio do miocárdio (RTM), a sequência de edema miocárdico (Spin-eco ponderado em T2) e a sequência de realce global precoce ponderado T1 pós-contraste, para identificar fibrose, edema e hiperemia miocárdicos, respectivamente. RESULTADOS: A fibrose miocárdica foi encontrada em 39 indivíduos, 72,2% de toda a amostra. A fibrose miocárdica foi detectada em 2 pacientes (12,5%) na forma indeterminada, com uma massa de fibrose média de 0,85 ± 2,47g. Os pacientes da forma CC-SD em sua quase totalidade - 16 pacientes (94,1%) - apresentaram fibrose, com uma massa média de 13,0 ± 10,8g. Todos os pacientes com a forma CC-CD apresentaram fibrose miocárdica (21 pacientes) e adicionalmente detinham a maior massa de fibrose média, 25 ± 11,9g. O edema miocárdico foi encontrado em 40 indivíduos, 74,0% de toda a amostra. A extensão do edema miocárdico foi analisada pelo número de segmentos comprometidos. Foram identificados 3 pacientes (18,8%) da forma indeterminada com critérios positivos para edema miocárdio, determinando uma média de 0,31 ± 0,87 segmentos. A forma CC-SD obteve a presença de edema em 16 indivíduos (94,1%) distribuídos em uma média de 3,24 ± 2,3 segmentos. Todos os pacientes da forma CC-CD apresentaram edema miocárdico pela RMC, em uma média 3,67 ± 1,82 segmentos (p < 0,001). Houve correlação significativa entre a quantidade de fibrose miocárdica e edema miocárdico com a gravidade das formas clínicas (p < 0,001), classe funcional (p < 0,001), fração de ejeção do VE (p < 0,001) e volume diastólico do VE(p < 0,001). CONCLUSÃO: Fibrose e inflamação miocárdica foram detectadas pela ressonância magnética cardíaca em pacientes portadores de cardiopatia chagásica em todas as fases crônicas da doença, inclusive naqueles pacientes sem cardiopatia ou com cardiopatia sem disfunção ventricular. A quantidade de fibrose e edema miocárdico apresenta correlação com a gravidade da forma clínica, classe funcional, fração de ejeção do VE e dilatação do VE / BACKGROUND AND PURPOSE: Chagas\' heart disease (CHD) is a major public health problem in South America, and the pathogenesis of this disease is not yet fully understood, but inflammation and myocardial fibrosis seem to play a central role in the process of chronic and progressive myocardial damage. Previous descriptions from our group demonstrated the ability of Cardiovascular Magnetic Resonance (CMR) accurately identify myocardial fibrosis in patients with CHD. CMR shown to be effective for assessing myocardial edema, a marker of inflammation, and is highly sensitive for the detection of thrombi, especially in the left ventricle in other pathologies such as myocarditis and myocardial infarct. The assessment of myocardial edema by CMR in patients with CHD has not been evaluated. We believe to be of potential diagnostic and prognostic value to investigate the presence of myocardial edema and fibrosis in patients in the three clinical forms of this disease. METHODS: Fifty-four patients with Chagas\' disease were analyzed: 16 patients with the indeterminate phase (IF), 17 patients with the cardiac form without left ventricular systolic dysfunction (CFWO), and 21 patients with the cardiac form with left ventricular systolic dysfunctional form (CFSD). All patients underwent 1.5-T cardiac magnetic resonance (CMR) using the myocardial delayed enhancement sequence (MDE), T2-weighted sequence and the T1 weighted global enhancement after contrast sequence, to identify fibrosis, edema and hyperemia, respectively. RESULTS: Myocardial fibrosis was found in 39 subjects, 72.2% of the entire sample. Myocardial fibrosis was detected in 2 patients (12.5%) with the indeterminate form, representing an average mass of fibrosis of 0.85 ± 2.47 g. Patients with the CFWO almost entirely, 16 patients (94.1%) showed fibrosis, representing an average mass of fibrosis of 13.0 ± 10.8 g. All patients with the CFSD had myocardial fibrosis (21 patients) additionally had greater average mass of fibrosis 11.9 ± 25g. The myocardial edema was found in 40 subjects, 74.0% of the entire sample. The extent of myocardial edema was determined by the number of segments affected. We identified three patients (18.8%) from the indeterminate form with myocardial edema, an average of 0.31 ± 0.87. The CFWO presented a high presence of edema in 16 individuals (94.1%) distributed in an average of 3.24 ± 2.3 segments. All patients with the CFSD presented myocardial edema, an average of 3.67 ± 1.82 segments. (p < 0.001). There was significant correlation between the amount of myocardial fibrosis and myocardial edema with the severity of the clinical forms ( p < 0.001 ), functional class ( p < 0.001 ), LV ejection fraction ( p < 0.001 ) and left ventricular diastolic volume ( p < 0.001). CONCLUSION: Myocardial fibrosis and inflammation were detected by cardiac magnetic resonance imaging in patients with Chagas\' disease in all stages of chronic disease, including those patients without heart disease or cardiomyopathy without ventricular dysfunction. The amount of fibrosis and myocardial edema correlates with the severity of the clinical, functional class, LV ejection fraction and LV dilation
28

Messung des reaktiven Anstiegs der Durchblutung des M. biceps brachii von Frauen mittels Farbduplexsonographie nach isometrischer Belastung / Measurement of the reactive increase in blood flow to the M. biceps brachii of women using color duplex sonography after isometric load.

Drohomirecka, Marzena 11 March 2010 (has links)
No description available.
29

Reactive Hyperemia as endothelial function determinant using plethysmography methods

Olamaei, Nina 01 1900 (has links)
L’atteinte de la fonction endothéliale représente une phase précoce de l’athérosclérose, un stade où les patients sont généralement asymptomatiques. Il existe donc un intérêt certain à détecter la dysfonction endothéliale. Nous avons développé une technique de mesure des variations de flot artériel au niveau des membres supérieurs, basée sur la spectroscopie proche infrarouge (NIRS). Cette approche permettrait d’étudier le niveau d’atteinte vasculaire et probablement de quantifier le degré de dysfonction endothéliale périphérique lors d’une hyperémie réactive. L'expérience a été exécutée sur deux cohortes de 13 et de 15 patients et a été comparée à la pléthysmographie par jauge de contrainte (SGP) qui est considérée comme une méthode de référence. Par la suite, nous avons caractérisé la réponse endothéliale par modélisation de la courbe hyperémique du flot artériel. Des études préliminaires avaient démontré que la réponse hyperémique adoptait majoritairement une forme bi-modale. Nous avons tenté de séparer les composantes endothéliales-dépendantes et endothéliales-indépendantes de l’hyperémie. La quantification des deux composantes de la réaction hyperémique permet de calculer un indice de la ‘santé’ du système endothélial local. Cet indice est nommé le ηfactor. Les résultats montrent une forte corrélation des mesures de flots entre la technique développée et la méthode de référence (r=0.91). Nous avons conclu que NIRS est une approche précise pour la mesure non-invasive du flot artériel. Nous avons obtenu une bonne répétabilité (ICC = 0.9313) pour le ηfactor indiquant sa robustesse. Cependant des études supplémentaires sont nécessaires pour valider la valeur de diagnostic du facteur défini. Mots clés: hyperémie réactive, réponse myogénique, oxyde nitrique, athérosclérose, spectroscopie proche infrarouge / Atherosclerotic diseases are mainly caused by coronary and peripheral blood vessel disorders. Endothelial dysfunction represents an early phase in these diseases, when patients are generally asymptomatic. We developed a technique, based on near infrared spectroscopy (NIRS), for measurement of arterial blood flow variations in limbs during reactive hyperemia. The technique allows the study of the level of vascular impairment and probably quantifying the level of endothelial dysfunction at peripheral arteries. The experiment was performed on two cohorts of 13 and 15 patients and was compared to strain gauge plethysmography (SGP) which is considered as gold standard. Afterward, we characterized endothelial reaction during reactive hyperemia through blood flow variations by modeling the hyperemic curve. Preliminary studies have shown that the hyperemic response generally adopts a bimodal form. The first peak was attributed to myogenic reaction that is endothelial independent and the second one to local endothelial cells reaction. The quantification of the two hyperemic response components makes it possible to calculate an index of ‘health’ for local endothelial cells, named ηfactor. The results showed a strong correlation (r = 0.91) of blood flow measurements between the developed method and the gold standard. We concluded that NIRS is a precise technique for non-invasive measurement of blood flow. Moreover, we found a high repeatability (ICC = 0.9313) of the ηfactor in repeated measurements indicating its robustness. Nonetheless, more studies are required to validate the diagnosis value of the defined factor. Key words: reactive hyperemia, myogenic response, endothelial dependent vasodilatation, nitric oxide, atherosclerosis, near infrared spectroscopy (NIRS)
30

Avaliação da inflamação miocárdica na doença de Chagas por ressonância magnética cardiovascular / Detection of myocardial inflammation in Chagas\' heart disease by cardiac magnetic resonance

Jorge Andion Torreão 12 March 2015 (has links)
INTRODUÇÃO: A cardiopatia chagásica (CC) é um importante problema de saúde pública na América do Sul e a patogênese desta doença ainda não é totalmente compreendida, mas a inflamação e a fibrose miocárdica participam de forma central no processo crônico e progressivo de dano miocárdico. Trabalho prévio de nosso grupo demonstrou a capacidade da Ressonância Magnética Cardiovascular (RMC) de identificar precisamente a fibrose miocárdica em pacientes com Doença de Chagas. A RMC demonstrou ser eficaz para avaliar edema miocárdico, como marcador de inflamação, e ser altamente sensível para a detecção de trombos intracavitários, especialmente no ventrículo esquerdo, e em outras patologias, como miocardites e infartos. A avaliação de edema miocárdio pela RMC em pacientes com CC não foi ainda avaliada na literatura. Nosso objetivo foi investigar a presença de edema e fibrose miocárdica nas três formas clínicas da CC, o que julgamos ser de potencial valor diagnóstico e prognóstico. MÉTODOS: Cinquenta e quatro pacientes com doença de chagas foram analisados: 16 pacientes com a forma indeterminada (FI), 17 pacientes com CC-SD e 21 pacientes com CC-CD. Todos os pacientes foram submetidos a exame de RMC em equipamento de 1,5 T, utilizando a sequência de realce tardio do miocárdio (RTM), a sequência de edema miocárdico (Spin-eco ponderado em T2) e a sequência de realce global precoce ponderado T1 pós-contraste, para identificar fibrose, edema e hiperemia miocárdicos, respectivamente. RESULTADOS: A fibrose miocárdica foi encontrada em 39 indivíduos, 72,2% de toda a amostra. A fibrose miocárdica foi detectada em 2 pacientes (12,5%) na forma indeterminada, com uma massa de fibrose média de 0,85 ± 2,47g. Os pacientes da forma CC-SD em sua quase totalidade - 16 pacientes (94,1%) - apresentaram fibrose, com uma massa média de 13,0 ± 10,8g. Todos os pacientes com a forma CC-CD apresentaram fibrose miocárdica (21 pacientes) e adicionalmente detinham a maior massa de fibrose média, 25 ± 11,9g. O edema miocárdico foi encontrado em 40 indivíduos, 74,0% de toda a amostra. A extensão do edema miocárdico foi analisada pelo número de segmentos comprometidos. Foram identificados 3 pacientes (18,8%) da forma indeterminada com critérios positivos para edema miocárdio, determinando uma média de 0,31 ± 0,87 segmentos. A forma CC-SD obteve a presença de edema em 16 indivíduos (94,1%) distribuídos em uma média de 3,24 ± 2,3 segmentos. Todos os pacientes da forma CC-CD apresentaram edema miocárdico pela RMC, em uma média 3,67 ± 1,82 segmentos (p < 0,001). Houve correlação significativa entre a quantidade de fibrose miocárdica e edema miocárdico com a gravidade das formas clínicas (p < 0,001), classe funcional (p < 0,001), fração de ejeção do VE (p < 0,001) e volume diastólico do VE(p < 0,001). CONCLUSÃO: Fibrose e inflamação miocárdica foram detectadas pela ressonância magnética cardíaca em pacientes portadores de cardiopatia chagásica em todas as fases crônicas da doença, inclusive naqueles pacientes sem cardiopatia ou com cardiopatia sem disfunção ventricular. A quantidade de fibrose e edema miocárdico apresenta correlação com a gravidade da forma clínica, classe funcional, fração de ejeção do VE e dilatação do VE / BACKGROUND AND PURPOSE: Chagas\' heart disease (CHD) is a major public health problem in South America, and the pathogenesis of this disease is not yet fully understood, but inflammation and myocardial fibrosis seem to play a central role in the process of chronic and progressive myocardial damage. Previous descriptions from our group demonstrated the ability of Cardiovascular Magnetic Resonance (CMR) accurately identify myocardial fibrosis in patients with CHD. CMR shown to be effective for assessing myocardial edema, a marker of inflammation, and is highly sensitive for the detection of thrombi, especially in the left ventricle in other pathologies such as myocarditis and myocardial infarct. The assessment of myocardial edema by CMR in patients with CHD has not been evaluated. We believe to be of potential diagnostic and prognostic value to investigate the presence of myocardial edema and fibrosis in patients in the three clinical forms of this disease. METHODS: Fifty-four patients with Chagas\' disease were analyzed: 16 patients with the indeterminate phase (IF), 17 patients with the cardiac form without left ventricular systolic dysfunction (CFWO), and 21 patients with the cardiac form with left ventricular systolic dysfunctional form (CFSD). All patients underwent 1.5-T cardiac magnetic resonance (CMR) using the myocardial delayed enhancement sequence (MDE), T2-weighted sequence and the T1 weighted global enhancement after contrast sequence, to identify fibrosis, edema and hyperemia, respectively. RESULTS: Myocardial fibrosis was found in 39 subjects, 72.2% of the entire sample. Myocardial fibrosis was detected in 2 patients (12.5%) with the indeterminate form, representing an average mass of fibrosis of 0.85 ± 2.47 g. Patients with the CFWO almost entirely, 16 patients (94.1%) showed fibrosis, representing an average mass of fibrosis of 13.0 ± 10.8 g. All patients with the CFSD had myocardial fibrosis (21 patients) additionally had greater average mass of fibrosis 11.9 ± 25g. The myocardial edema was found in 40 subjects, 74.0% of the entire sample. The extent of myocardial edema was determined by the number of segments affected. We identified three patients (18.8%) from the indeterminate form with myocardial edema, an average of 0.31 ± 0.87. The CFWO presented a high presence of edema in 16 individuals (94.1%) distributed in an average of 3.24 ± 2.3 segments. All patients with the CFSD presented myocardial edema, an average of 3.67 ± 1.82 segments. (p < 0.001). There was significant correlation between the amount of myocardial fibrosis and myocardial edema with the severity of the clinical forms ( p < 0.001 ), functional class ( p < 0.001 ), LV ejection fraction ( p < 0.001 ) and left ventricular diastolic volume ( p < 0.001). CONCLUSION: Myocardial fibrosis and inflammation were detected by cardiac magnetic resonance imaging in patients with Chagas\' disease in all stages of chronic disease, including those patients without heart disease or cardiomyopathy without ventricular dysfunction. The amount of fibrosis and myocardial edema correlates with the severity of the clinical, functional class, LV ejection fraction and LV dilation

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