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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.
51

Living-donor liver transplantation for pediatric liver disease with moderate or severe porto-pulmonary hypertension accompanied by pulmonary arterial hypertension / 中等度から重度門脈肺高血圧症を伴う小児肝疾患に対する生体肝移植術

Ogawa, Eri 23 January 2018 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13138号 / 論医博第2138号 / 新制||医||1025(附属図書館) / (主査)教授 伊達 洋至, 教授 坂井 義治, 教授 武藤 学 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
52

CT Findings of Pulmonary Hypertension

Patel, Akash 25 May 2017 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Primary pulmonary hypertension (PPH) has an extremely poor prognosis with a mean survival time of 2‐3 years from time of diagnosis. Hemodynamically, PPH is defined with a mPAP of ≥ 25 mm Hg. Currently, RHC is the gold standard for measuring the arterial pressures and diagnosing PPH; however, it is an incredibly invasive procedure. Our study will show whether CT angiography can be considered as a non‐invasive alternative for diagnosing PPH. Studies in the past have shown CT measurements of the MPAD and MPAD/AAD ratio having strong correlations with PPH. In addition to those measurements, we want to show if other CT parameters also have a correlation with PPH. Some of these novel measurements include the interventricular septal deviation and the Elizabeth Taylor sign. The interventricular septum is normally bowing to the right in a non‐pathological state. If it is straight or bowing to the left, this will indicate increased right ventricular pressures which would be indicative of PPH. Straight will indicate increased RV pressures, and bowing to the left will be considered markedly increased RV pressures. The Elizabeth Taylor sign is the ratio of the diameter of the segmental bronchi and its corresponding artery. We will hypothesize that the artery will be much larger than the bronchi in patients with PPH. Other measurements will include the left and right pulmonary arteries. This study is a retrospective review of subjects who underwent an otherwise unremarkable CT pulmonary artery angiogram. Subjects with pulmonary embolism or other acute pulmonary diseases are excluded. For each subject, the following CT findings are obtained: main pulmonary artery diameter (mPAD), ratio of mPAD to ascending aorta, right and left pulmonary artery diameters, ratio of segmental pulmonary artery to corresponding bronchus, and interventricular septal displacement. Straightening of the interventricular septum qualifies as increased right ventricular septal pressure and right‐to‐left bowing of the septum qualifies as a marked increase. Mean pulmonary artery pressure measured on any prior/subsequent RHC or echocardiogram within 3 months of the CT is recorded. Any past medical history of connective tissue disease is noted. Descriptive data are calculated and correlations are done to assess for presence and strength of associations among variables. Data from 484 subjects are collected. Incidence rate of pulmonary hypertension isv13% (n=63). 52% (n=33) of the subjects with pulmonary hypertension are female with an average age of 55 years. mPA diameter (p<0.001), mPA:AA ratio (p<0.001), right (p<0.001) and left pulmonary artery (p=0.004) diameters are predictors of pulmonary hypertension. sPA:B ratio (p=0.08) and interventricular septal displacement (p=0.96) are not predictive of pulmonary hypertension. This study supports an association of mPA diameter, mPA:AA ratio, right and left pulmonary artery diameters with pulmonary hypertension diagnosed by RHC or echocardiogram. Prospective research is warranted to confirm and establish threshold values for each variable. Currently, an invasive RHC remains the most accurate method of diagnosis. Correlating CT findings with pulmonary hypertension would allow clinicians to use CT as a noninvasive screening tool.
53

Lung function in relation to exercise capacity in health and disease

Farkhooy, Amir January 2017 (has links)
Background: Exercise capacity (EC) is widely recognized as a strong and independent predictor of mortality and disease progression in various diseases, including cardiovascular and pulmonary diseases. Furthermore, it is generally accepted that exercise capacity in healthy individuals and in patients suffering from cardiovascular diseases is mainly limited by the maximum cardiac output. Objectives: This thesis investigated the impact of different lung function indices on EC in healthy individuals, patients with cardiovascular disease (e.g., pulmonary hypertension (PH)) and patients with pulmonary disease (e.g., chronic obstructive pulmonary disease (COPD)). Methods: The present thesis is based on cross-sectional and longitudinal analyses of patients suffering from COPD, attending pulmonary rehabilitation at Uppsala University Hospital (studies I and II), and healthy men enrolled in the “Oslo ischemia study” (study IV). Study III is a cross-sectional study of patients suffering from PH attending the San Giovanni Battista University Hospital in Turin. EC was assessed using a bicycle ergometer in studies I and IV, with 12-minute walk tests (12MWT) in study II and with 6-minute walk tests (6MWT) in study III. Extensive pulmonary function tests, including diffusing capacity of the lung (DLCO), were performed in studies I-III and dynamic spirometry was used to assess lung function in study IV. Results: DLCO is more closely linked to decreased levels of EC than airway obstruction in COPD patients. Furthermore, the decline in 12MWT over a 5-year period was mainly explained by deterioration in DLCO in COPD patients. Spirometric parameters indicating airway obstruction significantly related to EC and exercise-induced desaturation in PH patients. A significant, but weak association between lung function parameters and EC was found in healthy subjects and this association is strengthened with increasing age. Conclusion: DLCO is the strongest predictor of low EC and EC decline in COPD. In PH, airway obstruction is strongly related to reduced 6MWT. Therefore, extensive analysis of lung function, including measurements of diffusing capacity, along with standard assessment of airway obstruction, gives a more comprehensive assessment of the functional exercise capacity in patients suffering from pulmonary hypertension or COPD. Lung function is also significantly linked to EC even in healthy subjects, lacking evident cardiopulmonary diseases.
54

Avaliação de hipertensão pulmonar em pacientes com linfangioleiomiomatose / Evaluation of pulmonary hypertension in patients with lymphangioleiomyomatosis

Chulam, Carolina Salim Gonçalves Freitas 08 June 2017 (has links)
Introdução: A linfangioleiomiomatose (LAM) está associada a HP e está incluída no grupo 5 da classificação atual (mecanismos multifatoriais desconhecidos). No entanto, os dados referentes à ocorrência de HP na LAM são escassos. Os objetivos do estudo foram avaliar a prevalência e as características da HP em pacientes com LAM em diferentes estágios de evolução, além de comparar as características clínicas, funcionais, do teste de caminhada de 6 minutos (TC6M) e da qualidade de vida das pacientes com e sem HP. Metodologia: Cento e cinco pacientes com LAM foram submetidos a ecocardiograma, prova de função pulmonar (PFP) e TC6M. Pacientes com suspeita de HP no ecocardiograma, definida pela presença de pressão arterial pulmonar sistólica estimada (PsAP) acima de 35 mmHg, ou PFP mostrando DLco abaixo de 40% do valor previsto, foram submetidos a cateterismo cardíaco direito para confirmar o diagnóstico de HP. Resultados: Oito pacientes (7,6%) tinham HP confirmada no cateterismo cardíaco direito, seis pacientes (5,7%) tinham padrão pré-capilar e dois pacientes (1,9%) tinham padrão pós-capilar. Apenas um paciente (1%) apresentou pressão média de artéria pulmonar (PAPm) acima de 35 mmHg. Os pacientes com HP apresentaram menor VEF1 e DLco em PFP e maior dessaturação de oxigênio e intensidade de dispneia durante o TC6M comparado com aqueles sem PH. Em 63% dos pacientes com HP confirmada, o cateterismo cardíaco direito foi realizado devido ao resultado do DLco. Conclusões: A prevalência de HP é baixa em pacientes com LAM. A hipertensão pulmonar é de pouca gravidade e significativamente associada ao envolvimento parenquimatoso pulmonar. A capacidade de difusão de monóxido de carbono foi bastante útil na identificação de HP em pacientes com LAM / Introduction: Lymphangioleiomyomatosis (LAM) is associated with pulmonary hypertension (PH) and is included in group 5 of the current classification (unknown multifactorial mechanisms). However, data regarding the occurrence of PH in LAM are scarce. The objectives of the study were to evaluate the prevalence and characteristics of PH in patients with LAM at different stages of evolution, as well as to compare the clinical and functional characteristics of the 6-minute walk test (6MWT) and the quality of life of patients with and without PH. Methodology: One hundred and five patients with LAM underwent echocardiogram, pulmonary function test (PFT) and 6MWT. Patients with suspected PH on the echocardiogram, defined as the presence of estimated systolic pulmonary arterial pressure (PsAP) above 35 mmHg, or PFT showing carbon monoxide diffusion (DLco) below 40% of the predicted value, were submitted to right cardiac catheterization to confirm the diagnosis of PH. Results: Eight patients (7.6%) had PH confirmed in right cardiac catheterization, six patients (5.7%) had a pre-capillary pattern and two patients (1.9%) had a post capillary pattern. Only one patient (1%) presented mean pulmonary artery pressure (PAPm) above 35 mmHg. Patients with PH had lower FEV1 and DLco in PFP and greater oxygen desaturation and dyspnea intensity during the 6MWT compared to those without PH. In 63% of patients with confirmed PH, right heart catheterization was performed because of the DLco result. Conclusions: The prevalence of PH is low in patients with LAM. Pulmonary hypertension is commonly mild and is significantly associated with pulmonary parenchymal involvement. The measure DLco has improved the identification of PH in patients with LAM
55

Qualidade de vida em hipertensão arterial pulmonar e sua relação com o desempenho físico: avaliação longitudinal / Health-related quality of life in pulmonary arterial hypertension and its relationship with the exercise capacity: a longitudinal study

Cicero, Cristina 07 May 2012 (has links)
A qualidade de vida relacionada à saúde tem aparecido, com frequência, entre as metas dos estudos clínicos destinados ao desenvolvimento de novos tratamentos para a hipertensão arterial pulmonar (HAP). Embora os novos tratamentos melhorem o desempenho ao exercício na fase inicial de 12 - 16 semanas, não se sabe se existe associação entre tolerância ao exercício e qualidade de vida (QV), sobretudo em médio e longo prazo. Os objetivos do estudo foram: a) verificar, em pacientes com HAP, a existência ou não de correlação entre a QV e desempenho físico; b) verificar como as possíveis associações entre QV e desempenho ao exercício se comporta ao longo de um ano de observação sob tratamento medicamentoso específico; c) verificar se a aplicação de um protocolo de orientação de enfermagem, especificamente planejado para pacientes com HAP, poderia exercer impacto sobre a QV e o desempenho físico. Foram incluídos 34 pacientes no estudo, adolescentes ou adultos com o diagnóstico de HAP idiopática, hereditária ou associada a cardiopatias congênitas. Para o comprimento do terceiro objetivo, os pacientes foram organizados em pares, seguindo-se randomização para o tipo de seguimento a que seriam submetidos: apenas orientação médica ou orientação médica seguida de consulta de enfermagem. O acompanhamento constou de cinco visitas, a saber, no início, e aos três, seis, nove e 12 meses. Nas visitas, foram avaliados o desempenho físico, através da classe funcional e do teste de caminhada de seis minutos, e a QV mediante aplicação do questionário SF-36. A idade variou entre 14 e 58 anos (mediana de 35,5 anos). Houve dez pacientes com o diagnostico de hipertensão arterial pulmonar idiopática, dois na forma hereditária e 22 indivíduos com a forma associada a cardiopatias congênitas. Com relação à classe funcional, 25 pacientes estavam em classe II e nove em classe III. A distância caminhada inicialmente foi 177 a 564 metros (mediana 399 metros). A saturação periférica de oxigênio em repouso esteve entre 63 e 98% (mediana 94,5%), e ao final do exercício, foi de 38 a 98% (mediana de 84%). Com relação aos escores de QV iniciais (valores de zero a 100, representando respectivamente pior e melhor estado de saúde), somente duas das oito categorias analisadas através do questionário SF-36 mostraram valores medianos abaixo de 50, ambas relacionadas à saúde física. Analisando-se os 31 pacientes que completaram 12 meses de seguimento, observou-se que não houve modificação com significância estatística na classe funcional, distância caminhada aos seis minutos, na saturação periférica de oxigênio e nos escores do questionário SF-36, componentes físico e mental da QV. Analisando-se todas as 40 possíveis correlações entre a distância caminhada e as oito diferentes categorias do questionário, observou-se 12 associações significantes ao longo do seguimento (p< 0,05, relacionado ao coeficiente rS de Spearman). O limite em termos de distância caminhada abaixo do qual os pacientes passariam a expressar maior insatisfação em relação à sua QV (escores 25) situou-se entre 235 e 285 metros percorridos, com especificidade superior a 0,90. Entretanto, a baixa sensibilidade (máxima 0,42) sugeriu que diversos pacientes expressariam tal descontentamento mesmo com desempenho físico acima do intervalo mencionado. Com relação ao tipo de consulta, ainda que subjetivamente se tenha observado maior esclarecimento quanto à doença e seu tratamento em alguns pacientes acompanhados com a consulta suplementar de enfermagem, não houve diferenças estatísticas quanto à classe funcional, distância percorrida aos seis minutos ou escores de QV. Os dados observados permitiram concluir que pacientes portadores de HAP, nas subcategorias diagnósticas analisadas, uma vez colocados em tratamento específico, se mantêm estáveis, em médio prazo, sem deterioração significante de seu desempenho físico e QV. Apesar do tratamento em curso, o maior grau de insatisfação está relacionado à percepção da saúde física. Evolutivamente, a associação entre desempenho físico e QV existe em apenas 30% das oportunidades avaliadas. Pacientes caminhando, menos de 235 metros no teste de caminhada, quase certamente expressarão insatisfação marcante em relação à sua QV. Finalmente, com respeito à consulta de enfermagem, embora subjetivamente se tenha tido impressão de seu real papel, não houve impacto demonstrado objetivamente com significância estatística. Assim, desempenho físico e QV se mostram como aspectos complementar a serem avaliados em pacientes com HAP / Health-related quality of life (HRQOL) has been explored as an additional end point in clinical studies for development of new therapies in pulmonary arterial hypertension (PAH). Although treatments have been shown to improve the exercise capacity in 12-16 weeks, little is known of how patients do over the medium and long term on these therapies, in terms of HTQOL. The objectives of the present study were: 1- to observe how PAH patients do on specific therapies over 12 months of follow-up in terms of the exercise capacity and HRQOL; 2- to test for possible associations between the exercise capacity and HRQOL, and determine if such associations persist over the medium term (12 months); 3- to examine if a PAH-specific nursing approach (following conventional visits to the doctor) has a positive impact on patients exercise capacity and quality of life. Thirty-four patients were enrolled, with PAH associated with congenital heart disease (N=22) or idiopathic/hereditary PAH (N=12). Patients were seen at baseline, and three, six, nine and twelve months thereafter. The exercise capacity was assessed by performing the six-minute walk test, and the quality of life using the SF-36 questionnaire. The functional class was recorded according to the World Health Organization classification. The age range was 14 to 58 years (median 35.5 years). Patients were in functional class II (N=25) or III (N=9), and baseline six-minute walked distance was 177 to 564 meters (median 399 meters). Peripheral oxygen saturation was 63% to 98% (median 94.5%) at rest, and 38% to 98% (median 84%) at the end of the exercise. At baseline, in two of the eight domains of the SF-36 questionnaire (physical functioning and physical role), median score were lower than 50 (0-100 scale, 100 indicating best health). In 31 patients who completed the follow-up, there were no statistically significant changes in the functional class, six-minute walked distance, peripheral oxygen saturation and SF-36 scores. All these variables remained stable in the whole patient group. Of 40 possible associations between the exercise capacity and aspects of HRQOL analyzed over 12 months, only 12 were statistically significant (p<0.05, Spearmans coefficient of correlation). Using regression models, it was observed that patients walking less than 235-280 meters during the six-minute test had a severe depression in HRQOL (SF-26 scores 25). Although the specificity was adequate (> 0.90) the low sensitivity of prediction ( 0.42) indicated that many patients would be unsatisfied with their quality of life even above this range. Nursing assistance did not add a significant benefit in terms of the sixminute walked distance or the SF-36 scores in PAH patients on treatment with specific therapies. On the basis of the present data, it is possible to conclude that patients on specific PAH therapies tend to remain stable over 12 months of observation in terms of the exercise capacity and HRQOL. It is noticeable that most patients in the study had PAH associated with congenital heart disease (no patients with systemic sclerosis included). Dissatisfaction in terms of HRQOL is mainly related to the perception of physical health. Over the medium term, associations between HRQOL and the exercise capacity are present in only 30% of instances, suggesting that these are different perspectives of patients health. Anyway, patients walking less than 235 meters in six-minutes are very likely to express severely depressed HRQOL. Finally, further studies possibly using qualitative research methodology are warranted for a better understanding of the role of nursing assistance in this disorder
56

Sobrevida em hipertensão pulmonar associada à esquistossomose mansônica / Survival in schistosomiasis associated pulmonary arterial hypertension

Fernandes, Caio Julio Cesar dos Santos 29 June 2010 (has links)
Introdução: A esquistossomose (Sch) é uma das doenças infecciosas crônicas mais prevalentes do mundo. Entretanto, dados a respeito de uma de suas complicações, a hipertensão arterial pulmonar (HAP), são escassos. O objetivo deste estudo é avaliar a história natural de pacientes com HAP-Sch comparados a pacientes com HAP idiopática (HAPI). Métodos: Análise retrospectiva dos prontuários de todos os pacientes consecutivamente diagnosticados como HAP-Sch e HAPI no Instituto do Coração, São Paulo, Brasil, entre 2004 e 2008. Nenhum dos pacientes com Sch-PAH recebeu tratamento específico para HAP enquanto todos os pacientes com HAPI receberam. Resultados: Pacientes com HAP-Sch (n=54) apresentavam hipertensão pulmonar menos grave ao diagnóstico, com menores níveis de resistência vascular pulmonar (11.3 ± 11.3 vs 16.7 ± 10.6 UI; p=0.002) e pressão média de artéria pulmonar (56.7 ± 18.7 vs. 64.6 ± 17.4 mmHg; p=0.01) e ainda maior débito cardíaco (4.62 ± 1.5 vs. 3.87 ± 1.5 L/min; p=0.009) quando comparados com os pacientes com HAPI (n=95). Nenhum dos pacientes HAP-Sch apresentou resposta positiva ao teste agudo com vasodilatador enquanto 16.2% dos pacientes com HAPI apresentaram (p=0.015). As taxas de sobrevida em 1, 2 e 3 anos foram 95.1%, 95.1%, 85.9% e 95%, 86% e 82%, para HAP-Sch e HAPI, respectivamente (p=0.49). Ambos os grupos tinham uma maior taxa de sobrevida quando comparadas àquela estimada pela equação do NIH para os pacientes com HAPI sem tratamento específico para HAP (71%, 61% e 52%, respectivamente). Conclusão: HAP-Sch tem um curso clínico mais benigno do que HAPI apesar da falta de vasorreatividade aguda na avaliação hemodinâmica inicial / Background: Schistossomiasis (Sch) is one of the most prevalent chronic infectious diseases in the world. Nevertheless data regarding one of its most severe clinical complications, pulmonary arterial hypertension (PAH), is scarce. The objective of this study was to evaluate the natural history of Sch-PAH patients as compared to idiopathic PAH (IPAH). Methods: We retrospectively analyzed case notes of all consecutive patients diagnosed of Sch-PAH and IPAH referred to the Heart Institute in São Paulo, Brazil, between 2004 and 2008. None of the Sch-PAH received PAH specific treatment whereas all IPAH patients did. Findings: Sch-PH patients (n=54) had less severe pulmonary hypertension as evidenced by lower levels of pulmonary vascular resistance (11.3 ± 11.3 vs 16.7 ± 10.6 IU; p=0.002) and mean pulmonary artery pressure (56.7 ± 18.7 vs. 64.6 ± 17.4 mmHg; p=0.01) and higher cardiac output (4.62 ± 1.5 vs. 3.87 ± 1.5 L/min; p=0.009) at presentation than IPAH patients (n=95). None of the Sch- PAH patients demonstrated a positive response to acute vasodilator testing, whereas 16.2% of IPAH patients did (p=0.015). Survival rates at 1, 2 and 3 years were 95.1%, 95.1%, 85.9% and 95%, 86% and 82%, for Sch-PAH and IPAH, respectively (p=0.49). Both groups had a higher survival rate when compared to untreated IPAH survival as estimated by the NIH equation (71%, 61% and 52%, respectively). Conclusion: Sch-PAH has a more benign clinical course than IPAH despite a lack of demonstrable acute vasoreactivity at hemodynamic evaluation
57

Avaliação da arteriopatia distal em pacientes com embolia pulmonar: estudo anátomo-patológico / Distal arteriopathy in patients with pulmonary emboli: anatomypathologic study

Arnoni, Renato Tambellini 05 March 2007 (has links)
O tromboembolismo pulmonar causado por obstrução de ramos arteriais pulmonares por trombos originados de outras partes do corpo apresenta elevada incidência. Em 5% dos casos ocorre a cronificação do processo e manutenção ou agravamento da hipertensão pulmonar Duas hipóteses explicam a cronificação nos casos de embolia pulmonar: 1. manutenção do fator oclusivo como fundamental para o desenvolvimento da resposta vascular pulmonar caracterizada por hipertrofia da camada média; 2. hipertensão pulmonar secundária a uma arteriopatia inicial, nos pacientes que evoluíram de maneira desfavorável. Este estudo tem por objetivo avaliar sob critérios histopatológicos qualitativos e quantitativos o comportamento do leito arterial pulmonar distal (pré e intra-acinar), comparativamente em pulmões de pacientes sem tromboembolismo prévio e de pacientes portadores de tromboembolismo agudo e crônico. Para tanto, estudou-se a resposta vascular através de estudo histológico de 31 casos de embolia (aguda e crônica), comparando-os com 24 pacientes do grupo controle (Infarto agudo do miocárdio) (análise de autópsias). As lâminas de tecido pulmonar foram preparadas e coradas em hematoxilina-eosina e Miller. A análise realizada foi dividida em qualitativa (vasoconstrição e proliferação intimal concêntrica) e quantitativa (hipertrofia da camada média). Foram observadas alterações histopatológicas do leito arterial pulmonar distal nos pacientes portadores de quadro tromboembólico agudo e crônico, em relação aos pacientes sem tromboembolismo prévio. Estas alterações, entre os grupos agudo e crônico, foram: diferentes quanto aos critérios qualitativos, caracterizadas por maior vasoconstrição nos quadros tromboembólicos agudos e maior proliferação intimal concêntrica nos crônicos; semelhantes quanto aos critérios quantitativos, caracterizadas por hipertrofia da camada média. A isquemia decorrente da obstrução parece exercer um importante papel nestas alterações, o que, entretanto, necessita de comprovação futura / The pulmonary embolism, caused by pulmonary artery branches obstruction from thrombus originated on other parts of the body, has a high incidence. However, just 5% of the cases develop the cronification and pulmonary hypertension. Two hypotheses can explain the cronification of tromboembolic pulmonary events: 1. maintenance of occlusive factor with pulmonary vascular response characterized by medial hypertrophy; 2. pulmonary hypertensive response as an initial arteriopathy in patients with bad evolution. This study aims to evaluate histologic aspects of pulmonary arterial bed (quantitative and qualitative), and to compare the results from embolic cases with non embolic cases. The study evaluated 55 patients (31 with pulmonary embolic disease and 24 in the control group myocardium infarction). From the selected cases, the blades with pulmonary tissue were colored by two techniques (haematoxilin-eosin and Miller). The analysis encompassed qualitative (vasoconstriction and intimal proliferation) and quantitative (mensuration of medial thickness) observations. It has been observed histologic changes between the two groups with pulmonary embolic disease (chronic or acute), and the control group. The changes between the embolic groups were: 1. higher vasoconstriction in the acute group, 2. more intimal proliferation in the chronic group, 3. no difference in the quantitative response (medial thickness). The ischemic response to obstruction can perform an important role in these changes, but further studies are necessary. There was a similar response in chronic and acute cases
58

Análise quantitativa automática da vasculatura pulmonar em TCAR de pacientes com hipertensão pulmonar / Automatic quantitative analysis of pulmonary vasculature on HRCT of patients with pulmonary hypertension

Melges, Gustavo Cabrera 01 June 2017 (has links)
A hipertensão pulmonar (HP) é uma doença caracterizada por elevação da pressão da artéria pulmonar e um aumento da resistência vascular pulmonar levando à disfunção do ventrículo direito, sendo complicação importante de doenças como a doença pulmonar obstrutiva crônica (DPOC), doença pulmonar intersticial (DPI), colagenoses e vasculites. A tomografia computadoriza de alta resolução (TCAR) é um dos principais métodos de diagnóstico e acompanhamento destas doenças. Neste estudo objetivamos a analise quantitativa dos exames de TCAR do tórax em pacientes com doenças parenquimatosas difusas e hipertensão pulmonar diagnosticada por cateterismo direito. Foram analisados retrospectivamente os prontuários eletrônicos e os exames de TCAR de 29 pacientes com HP, em comparação com um grupo controle. Foram excluídos os casos de hipertensão arterial pulmonar primária e tromboembolismo crônico, cuja investigação é feita prioritariamente com exame de angiotomografia. A análise quantitativa foi realizada utilizando programa completamente automático e algumas medidas manuais também foram realizadas. O pacientes com HP, quando comparados ao controle, apresentaram redução do volume pulmonar, aumento da atenuação média do parênquima, aumento na medida do volume vascular pulmonar, aumento da densidade vascular pulmonar e na relação do volume vascular nos lobos superiores em relação aos lobos inferiores. O programa automático foi capaz de identificar as alterações da vasculatura, mesmo em se tratando de exames não contrastados e em meio a alterações arquiteturais do parênquima pulmonar. Estes achados provavelmente representam a redistribuição da trama vascular pulmonar, relacionada ao aumento da resistência vascular pulmonar. A análise quantitativa automática, realizada em exames de TCAR já utilizados na rotina clínica, pode representar nova ferramenta não invasiva capaz de identificar sinais de HP em pacientes com fator de risco, como DPOC, DPI, colagenoses, em que a HP representa complicação importante e de diagnóstico muitas vezes difícil / Pulmonary hypertension (PH) is a disease characterized by elevation in the mean pressure of the pulmonary artery and an increase in the pulmonary vascular resistance leading to right heart dysfunction, being an important complication of multiple diseases such as chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), collagen diseases and vasculitis. The high resolution computed tomography (HRCT) is one of the main diagnostic methods and is also important in the follow up of these patients. In this study we aim the quantitative analysis of the thoracic HRCT exams in patients with diffuse parenchymal lung disease and pulmonary hypertension diagnosed by right heart catheterism. We analised retrospectively the clinical records and HRCT exams of 29 patients with PH, comparing to a control group. Were excluded from the study patients with primary pulmonary arterial hypertension (PAH) and chronic thromboembolism pulmonary hypertension (CTEPH), which investigations usually include pulmonary angiotomography. The quantitative analysis was made utilizing a completely automatic software and some manual measures were also noted. Patients with PH, when comparing to control group, presented significant pulmonary volume reduction, elevated mean parenchymal attenuation, elevated measures of the pulmonary vascular volume, increase in the pulmonary vascular density and also an elevation in the relation between vascular volume in the upper pulmonary lobes and the lower lobes. The automatic software was able to identify the vascular alterations, even in non contrast enhanced exams and amidst architectural distortions in the lung parenchyma. These findings probably represent the redistribution of the pulmonary vascular bed, related to the pulmonary vascular resistance increase. .The quantitative automatic analysis, made in HRCT exams, used in clinical practice, can represent a new non invasive tool, able to identify PH signs in risc patients, such as COPD, ILD and collagen diseases, in which PH represents an important complication with, many times, difficult diagnosis.
59

Avaliação do ventrículo direito nos pacientes com hipertensão pulmonar / Right ventricle evaluation in pulmonary hypertension

Hoette, Susana 20 August 2012 (has links)
Introdução: A fração de ejeção do ventrículo direito (FEVD) é um importante fator prognóstico em pacientes com hipertensão pulmonar (HP), porém a sua medida é complicada e demorada devido à complexidade anatômica do ventrículo direito (VD). O TAPSE (Tricuspid Annular Plane Systolic Excursion) é um bom índice da FEVD, mas ele avalia apenas o componente longitudinal da contração ventricular direita. A RVFAC (Right Ventricular Fractional Area Change) parece ser um melhor índice da FEVD por incluir os componentes longitudinal e transversal da contração ventricular direita. O objetivo deste estudo foi avaliar a performance da RVFAC de acordo com a gravidade do acometimento hemodinâmico em dois grupos distintos de pacientes portadores de HP pré-capilar: hipertensão arterial pulmonar (HAP) e tromboembolismo pulmonar crônico hipertensivo (TEPCH). Métodos: 62 pacientes realizaram cateterismo cardíaco direito e ressonância magnética cardíaca em ±72h. As áreas sistóica e diastólica finais do ventrículo direito (ASFVD, ADFVD), a área diastólica final do ventrículo esquerdo (ADFVE) e o TAPSE foram medidos nas imagens de quatro cavidades. A RVFAC (ADFVD-ASFVD/ADFVD) e a relação entre as áreas diastólica finais ventriculares (ADFVD/ADFVE) foram calculadas. Os diâmetros entre as paredes livre e septal (dL-S) e antero-posterior (dA-P) do ventículo esquerdo (VE) foram medidos nas imagens em eixo curto e o índice de excentricidade do VE (IE) foi calculado (=dA-P/dL-S). A FEVD foi calculada a partir de imagens consecutivas de 6mm no eixo curto. . Resultados: A população tinha 58 anos em média, a maioria era do sexo feminino e estava em classe funcional III, 23 tinham HAP e 39 TEPCH. A FEVD apresentou correlações fracas com as medidas hemodinâmicas de sobrecarga e de função do VD. A RVFAC apresentou melhor correlação (R2=0,65, p < 0,001) do que o TAPSE (R2=0,35, p<0,001) com a FEVD e melhor capacidade para estimar FEVD<35% do que o TAPSE (TAPSE: AUC 0,73 e RVFAC: AUC 0,93, p=0,0065). Dividimos a população pela mediana da resistência vascular pulmonar (RVP) e observamos que no grupo com maior gravidade hemodinâmica essa diferença se acentuou: no grupo com RVP<8,5UW (RVFAC: R2=0,66, p<0,001 e TAPSE: R2=0,30, e p=0,002) e no grupo com RVP>8,5UW (RVFAC: R2=0,51, p<0,001 e TAPSE: R2=0,14, e p=0,041). O grupo com RVP>8,5UW apresentou maior ADFVD/ADFVE e maior IE. As correlações da RVFAC e TAPSE com FEVD foram semelhantes entre os grupos HAP e TEPCH. Conclusão: A RVFAC se correlacionou melhor com a FEVD do que o TAPSE tanto no grupo com menor como no grupo com maior gravidade hemodinâmica. No grupo com maior gravidade as correlações da RVFAC com a FEVD foram ainda mais significativas, não havendo diferenças na performance da RVFAC entre os pacientes com HAP e TEPCH. A RVFAC foi um melhor índice da FEVD talvez por incluir o movimento transversal da contração ventricular / Introduction: The right ventricular ejection fraction (RVEF) is a surrogate marker in pulmonary hypertension (PH), but its measurement is complicated and time consuming. The TAPSE (Tricuspid Annular Plane Systolic Excursion) is a good index of RVEF, though it measures only the longitudinal component of right ventricular contraction. The RVFAC (Right Ventricular Fractional Area Change) seems to be a better index of RVEF because it takes into account the longitudinal and the transversal components of right ventricular contraction. The aim of our study was to evaluate the RVFAC performance according to hemodynamic severity in two groups of patients with PH: pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Methos: Sixty-two patients with PAH and CTEPH underwent right heart catheterization and cardiac MR in a 72-hour delay. The right and left ventricle end diastolic areas (RVEDA, LVEDA), the right ventricle end systolic area (RVESA) and TAPSE were measured in the four chamber view. The RVFAC (=RVEDARVESA/RVEDA) and the RVEDA/LVEDA relationship were calculated. The diameter between the left ventricle (LV) free wall and the septum (dF-S) and the diameter between the LV anterior and posterior walls (dA-P) were measured and the LV eccentricity index (EI) was calculated (=dA-P/dF-S). The RVEF was calculated by using 6 mm RV short axis cines. Results: The population had mean age of 58 years with female majority, most of the patients were in functional class III, 23 had PAH and 39 CTEPH. The RVEF was weakly correlated to the hemodynamic variables of RV afterload and function. The RVFAC was more strongly correlated to RVEF (R2=0.65, p<0.001) than TAPSE (R2=0.35, p<0.001). RVEF<35% was better predicted by RVFAC than TAPSE (TAPSE: AUC 0.73 and RVFAC: AUC 0.93, p=0.0065). We divided the population by the median of the pulmonary vascular resistance (PVR) and we observed that in the group with worse hemodynamic severity this difference increased: in the group with PVR<8,5WU (RVFAC: R2=0.66, p<0.001 and TAPSE: R2=0.30, p=0.002) and in the group with PVR>8,5 WU (RVFAC: R2=0.51, p<0.001 and TAPSE: R2=0.14, p=0.041). The group with PVR>8,5WU had an increased RVEDA/LVEDA and an increased EI. There was no differences in the RVEF relationships between the groups of PAH and CETPH. Conclusion: The RVFAC was better correlated to RVEF than TAPSE in the groups with less severe and more severe hemodynamics. In patients with increased hemodynamic severity RVFAC perfomed even better, there was no difference in the performance of RVFAC in PAH or CTEPH. RVFAC was a better index of RVEF possibly because it takes into account the transversal component of right ventricular function
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Advancements In pulmonary arterial hypertension treatment

Bains, Ashank 01 November 2017 (has links)
Pulmonary arterial hypertension is a rare, chronic disease characterized by progressive remodeling of the pulmonary vasculature. Historically, prognosis has been very poor with relatively low 3-year survival rates. Common symptoms include fatigue and shortness of breath upon exercise, chest pain, and syncope. Patients exhibit increased pressure and resistance in pulmonary arteries due to fibrosis, vessel narrowing, and elevated levels of vasoconstrictive agents; diagnosis is confirmed by right heart catheterization. Reduced blood flow through the pulmonary vasculature not only reduces the amount of oxygenated blood available for the systemic circulation, but increases afterload on the right ventricle and, if left untreated, ultimately causes right ventricular heart failure. In the past, few medications were available to pulmonary arterial hypertension patients. However, recent advancements in our molecular understanding of the disease have led to the development of new therapeutic options that show promise of slowing, or in some cases reversing, disease progression. Currently available treatments have been shown to significantly improve 3-year survival rates and help promote a better quality of life for patients. While an exact molecular or genetic mechanism of disease progression is not yet known, several studies have noted the presence of dysfunctional endothelial cells and an imbalance in molecular modulators of the pulmonary vasculature. Specifically, patients exhibit chronically low levels of vasodilating agents such as prostacyclin and nitric oxide. In addition, there is a heightened vasoconstrictive effect due to elevated endothelin-1 and thromboxane A2. Drugs have been developed to target these signaling pathways and show considerable promise and efficacy for managing pulmonary hypertension in patients. Although these therapeutics have been shown to significantly improve survival rates and symptoms, many have complex and inconvenient administration protocols and a host of adverse side effects. Moreover, many require monitoring or frequent follow up visits due to their off-target effects. Recent innovative advancements in pulmonary arterial hypertension pharmaceuticals hope to deliver safe, efficacious treatment options to patients debilitated by this chronic disease.

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