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Use of Computational Fluid Dynamics to Evaluate Energy Loss in Three Palliative Strategies of Hypoplastic Left Heart SyndromeNiehaus, Justin January 2010 (has links)
No description available.
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Lymphopenia in infants with Hypoplastic Left Heart SyndromePerez Ramirez, Leilanie 11 September 2015 (has links)
No description available.
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Estudo da remodelação cardíaca em pacientes com doença pulmonar obstrutiva crônicaColeta, Karina Dela [UNESP] 26 February 2010 (has links) (PDF)
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coleta_kd_dr_botfm.pdf: 391595 bytes, checksum: dde69b55ebd37c6d547a6c2e6321775d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pacientes com doença pulmonar obstrutiva crônica (DPOC) apresentam risco elevado para eventos cardiovasculares. Entretanto, existem poucos estudos sobre a função do ventrículo esquerdo (VE) nesses pacientes e os resultados são controversos. Os objetivos deste estudo foram: analisar a estrutura e função do ventrículo direito (VD) e câmaras cardíacas esquerdas, por meio de Dopplerecocardiografia, em pacientes com DPOC e avaliar a associação entre as variáveis ecocardiográficas e as variáveis clínicas relevantes. Foram avaliados 45 pacientes com DPOC (idade: 65,8 ± 10,6 anos, 64% homens): 17 pacientes com DPOC leve a moderada (grau I e II) provenientes do Serviço de Pneumologia da Faculdade de Medicina de Botucatu (FMB) e 28 pacientes com DPOC muito grave (grau IV) acompanhados no Ambulatório de Oxigenoterapia da FMB. Os critérios de inclusão foram: diagnóstico de DPOC, estabilidade clínica e, para os pacientes com DPOC IV, uso de oxigênio domiciliar por período mínimo de três meses. Para o grupo controle foram selecionados 15 indivíduos saudáveis (idade: 64,3 ± 10,1, 47% homens). Os critérios de exclusão foram: imagem ecocardiográfica inadequada, hipertensão arterial sistêmica, diabetes mellitus, doença coronariana, valvopatias, arritmias, patologias respiratórias associadas ou outras patologias cardíacas. Espirometria pré e pós-broncodilatador e oximetria de pulso foram realizadas por todos os sujeitos da pesquisa e gasometria arterial somente para os pacientes com DPOC... / Chronic obstructive pulmonary disease (COPD) is a strong risk factor for cardiovascular events. However, the status of left ventricle (LV) has been less studied and the results are controversial. The objectives were: to analyse the right ventricle (RV) and the left heart chambers structure and function in COPD patients by echocardiogram, and to analyse the association between echocardiographic variables and the relevant clinical variables. Forty-five COPD patients (age: 65,8 ± 10.6 years; 64% male) were evaluated: 17 mild to moderate COPD patients (grade I and II) and 28 very severe COPD patients (grade IV). The inclusion criteria were: COPD diagnosis, clinical stability and home oxygen therapy for at least three months (very severe COPD). The control group consisted of 15 healthy subjects (age: 64.3 ± 10.1 years; 47% male). Exclusion criteria were: poor quality echocardiographic image, history of systemic hypertension, diabetes mellitus, coronary artery disease, valvular heart disease, arrhythmias, associated lung diseases or other heart diseases. Pre and post-bronchodilator spirometry and pulse oximetry were performed in all subjects and arterial gasometry was performed in COPD patients only... (Complete abstract click electronic access below)
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Estudo da remodelação cardíaca em pacientes com doença pulmonar obstrutiva crônica /Coleta, Karina Dela. January 2010 (has links)
Resumo: Pacientes com doença pulmonar obstrutiva crônica (DPOC) apresentam risco elevado para eventos cardiovasculares. Entretanto, existem poucos estudos sobre a função do ventrículo esquerdo (VE) nesses pacientes e os resultados são controversos. Os objetivos deste estudo foram: analisar a estrutura e função do ventrículo direito (VD) e câmaras cardíacas esquerdas, por meio de Dopplerecocardiografia, em pacientes com DPOC e avaliar a associação entre as variáveis ecocardiográficas e as variáveis clínicas relevantes. Foram avaliados 45 pacientes com DPOC (idade: 65,8 ± 10,6 anos, 64% homens): 17 pacientes com DPOC leve a moderada (grau I e II) provenientes do Serviço de Pneumologia da Faculdade de Medicina de Botucatu (FMB) e 28 pacientes com DPOC muito grave (grau IV) acompanhados no Ambulatório de Oxigenoterapia da FMB. Os critérios de inclusão foram: diagnóstico de DPOC, estabilidade clínica e, para os pacientes com DPOC IV, uso de oxigênio domiciliar por período mínimo de três meses. Para o grupo controle foram selecionados 15 indivíduos saudáveis (idade: 64,3 ± 10,1, 47% homens). Os critérios de exclusão foram: imagem ecocardiográfica inadequada, hipertensão arterial sistêmica, diabetes mellitus, doença coronariana, valvopatias, arritmias, patologias respiratórias associadas ou outras patologias cardíacas. Espirometria pré e pós-broncodilatador e oximetria de pulso foram realizadas por todos os sujeitos da pesquisa e gasometria arterial somente para os pacientes com DPOC... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Chronic obstructive pulmonary disease (COPD) is a strong risk factor for cardiovascular events. However, the status of left ventricle (LV) has been less studied and the results are controversial. The objectives were: to analyse the right ventricle (RV) and the left heart chambers structure and function in COPD patients by echocardiogram, and to analyse the association between echocardiographic variables and the relevant clinical variables. Forty-five COPD patients (age: 65,8 ± 10.6 years; 64% male) were evaluated: 17 mild to moderate COPD patients (grade I and II) and 28 very severe COPD patients (grade IV). The inclusion criteria were: COPD diagnosis, clinical stability and home oxygen therapy for at least three months (very severe COPD). The control group consisted of 15 healthy subjects (age: 64.3 ± 10.1 years; 47% male). Exclusion criteria were: poor quality echocardiographic image, history of systemic hypertension, diabetes mellitus, coronary artery disease, valvular heart disease, arrhythmias, associated lung diseases or other heart diseases. Pre and post-bronchodilator spirometry and pulse oximetry were performed in all subjects and arterial gasometry was performed in COPD patients only... (Complete abstract click electronic access below) / Orientador: Irma de Godoy / Coorientador: Katashi Okoshi / Banca: Beatriz Matsubara / Banca: Leonardo Zornoff / Banca: Maria Inês Zanetti Feltrim / Banca: Oliver Augusto do Nascimento / Doutor
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Neurodevelopmental Outcomes in Infants with Hypoplastic Left Heart Syndrome after Hybrid Stage I PalliationCheatham, Sharon Laneau 20 December 2012 (has links)
No description available.
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Análise histomorfológica de corações com atresia e estenose mitral na síndrome do coração esquerdo hipoplásico / Histomorphologycal Analysis of Hearts with mitral atresia and stenosis in Hypoplastic Left Heart SyndromeAbuchaim, Décio Cavalet-Soares 26 August 2013 (has links)
Introdução: A Síndrome do Coração Esquerdo Hipoplásico (SCEH) compreende um espectro de malformações estruturais cardíacas caracterizadas por um hipodesenvolvimento significativo do complexo coração esquerdo-aorta, que apesar da evolução do tratamento, continua sendo um desafio. O objetivo deste trabalho é identificar diferenças morfológicas e histológicas em corações com atresia e estenose mitral na SCEH. Métodos: Estudo de 33 corações com SCEH e nove corações normais (controle), divididos em dois grupos, atresia mitral (AM) e estenose mitral (EM), obtidos em necrópsia e submetidos a análise morfológica dos segmentos da aorta, características da valva mitral e tricúspide, septo inter atrial, miocárdio, cavidades ventriculares e análise histológica com as colorações e hematoxilina/eosina e picro-sírius. Resultados: Observamos nove espécimes com Atresia Mitral e Atresia Aórtica (AMAA), 27,2%; treze com Atresia Mitral e Estenose Aórtica (AMEA), 39,3% e onze com Estenose Mitral e Estenose Aórtica (EMEA) 33,3%. Encontramos associação significativa de predominância de coronárias tortuosas no grupo EM (?2= 4,911; P=0,027) e a dominância coronariana esquerda está em 75% dos casos de EM, com diferença significativa entre os dois grupos (?2=9,298; P=0,01). No grupo AM encontramos correlação significativa entre aorta descendente e arco aórtico (r =0,692; P=0,039) e entre aorta descendente e istmo aórtico (r=0,796; P=0,010).No grupo EM, há correlação significativa entre as variáveis: Anel mitral e comprimento via de entrada de ventrículo direito (r=0,523; P=0,045); Anel mitral e istmo aórtico (r=0,692; P=0,003); ventrículo esquerdo cavidade e aorta ascendente (r=0,643; P=0,010); Arco aórtico e istmo aórtico (r=0,678; P=0,001); Aorta ascendente e arco aórtico (r=0,444; P = 0,044). Não existe diferença significativa no tamanho dos miócitos (coloração HE) entre o grupo AMAA e o grupo EMAA/EMEA (P=0,427), porém existe diferença significativa entre AMAA e controle (P=0,011) e entre EMAA/EMEA e controle (P=0,023). O percentual de colágeno (coloração de picro-sírius) é significantemente diferente entre os três grupos (P=0,0001) e o grupo AM é o que contém maior percentual de colágeno. Conclusões: 1. Na SCEH os corações com EM apresentam significativamente coronárias tortuosas e dominância coronariana esquerda em comparação com AM; 2. No grupo AM encontramos correlação significativa entre o diâmetro da aorta descendente e arco aórtico e entre aorta descendente e istmo aórtico; 3. No grupo EM, há correlação significativa entre as seguintes variáveis: anel mitral e comprimento via de entrada do ventrículo direito, anel mitral e istmo aórtico, cavidade do ventrículo esquerdo e aorta ascendente, arco aórtico e istmo aórtico e arco aórtico e aorta ascendente; 4. Há hipertrofia dos miócitos nos espécimes com AM e EM em comparação com o grupo controle; 5. Na SCEH o percentual de colágeno é superior ao grupo controle; 6. O grupo AM tem maior percentual de colágeno que o grupo EM / Introduction: Hypoplastic left heart syndrome (HLHS) comprises a spectrum of cardiac malformations characterized by a significant underdevelopment of the left heart-aorta complex, which remains a challenge despite the progress of treatment. The objective of this work is to identify morphological and histological differences in hearts with atresia and mitral stenosis with HLHS. Methods: 33 hearts with HLHS divided into two groups, mitral atresia (AM) and mitral stenosis (MS) and nine normal hearts (control),obtained at autopsy, submitted to morphological analysis of aortic segments, mitral and tricuspid valves, atrial septum, infarction, and ventricular cavities and histological study with Hematoxylin/eosin and picro sírius stain. Results: There were nine specimens with aortic atresia and mitral atresia (AMAA), 27.2%; thirteen with atresia Mitral and Aortic Stenosis (AMEA), 39.3% and eleven with Mitral Stenosis and Aortic Stenosis (EMEA) 33.3%. There is a significant association of prevalence of coronary tortuous in the MS group (x2 = 4.911, P=0.027) and left coronary dominance in 75% of cases of MS, with a significant difference between the two groups (x2 2 = 9.298, P=0,01). In the AM group we found a significant correlation between the descending aorta and aortic arch (r=0.692, P=0.039) and between the descending aorta and aortic isthmus (r =0.796, P=0.01). In the MS group there was a significant correlation between variables: mitral ring and length inlet right ventricle (r= 0.523, P=0.045), mitral and aortic isthmus (r=0.692, P=0.003), left ventricular cavity and ascending aorta (r=0.643, P=0.01); Aortic arch and aortic isthmus (r=0.678, P=0.001), ascending aorta and aortic arch (r=0.444, P=0.044).There is no significant difference in the size of myocites (HE staining) between the group and the group AMAA EMAA / EMEA (P = 0.427), but we found significant difference between AMAA and control (P = 0.011) and between EMAA / EMEA and control (P=0.023). The percentage of collagen (picrosirius staining) is different between the three groups (P=0.0001) and AM is the group that contains a higher percentage of collagen. Conclusions: 1. In HLHS hearts with MS present significant tortuous coronary and left coronary dominance compared with AM; 2. In the AM group there is a significant correlation between the diameter of the descending aorta and aortic arch and descending aorta and across the aortic isthmus; 3. In the MS group, there was significant correlation between the following variables: length and mitral inflow tract, mitral and aortic isthmus, left ventricular cavity and the ascending aorta, aortic arch and isthmus aorta and aortic arch and ascending aorta; 4. There is myocite hypertrophy in specimens with AM and EM compared with control; 5. In the HSLS collagen percentage is higher than control; 6. The AM group has a higher percentage of collagen than the EM group
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Análise histomorfológica de corações com atresia e estenose mitral na síndrome do coração esquerdo hipoplásico / Histomorphologycal Analysis of Hearts with mitral atresia and stenosis in Hypoplastic Left Heart SyndromeDécio Cavalet-Soares Abuchaim 26 August 2013 (has links)
Introdução: A Síndrome do Coração Esquerdo Hipoplásico (SCEH) compreende um espectro de malformações estruturais cardíacas caracterizadas por um hipodesenvolvimento significativo do complexo coração esquerdo-aorta, que apesar da evolução do tratamento, continua sendo um desafio. O objetivo deste trabalho é identificar diferenças morfológicas e histológicas em corações com atresia e estenose mitral na SCEH. Métodos: Estudo de 33 corações com SCEH e nove corações normais (controle), divididos em dois grupos, atresia mitral (AM) e estenose mitral (EM), obtidos em necrópsia e submetidos a análise morfológica dos segmentos da aorta, características da valva mitral e tricúspide, septo inter atrial, miocárdio, cavidades ventriculares e análise histológica com as colorações e hematoxilina/eosina e picro-sírius. Resultados: Observamos nove espécimes com Atresia Mitral e Atresia Aórtica (AMAA), 27,2%; treze com Atresia Mitral e Estenose Aórtica (AMEA), 39,3% e onze com Estenose Mitral e Estenose Aórtica (EMEA) 33,3%. Encontramos associação significativa de predominância de coronárias tortuosas no grupo EM (?2= 4,911; P=0,027) e a dominância coronariana esquerda está em 75% dos casos de EM, com diferença significativa entre os dois grupos (?2=9,298; P=0,01). No grupo AM encontramos correlação significativa entre aorta descendente e arco aórtico (r =0,692; P=0,039) e entre aorta descendente e istmo aórtico (r=0,796; P=0,010).No grupo EM, há correlação significativa entre as variáveis: Anel mitral e comprimento via de entrada de ventrículo direito (r=0,523; P=0,045); Anel mitral e istmo aórtico (r=0,692; P=0,003); ventrículo esquerdo cavidade e aorta ascendente (r=0,643; P=0,010); Arco aórtico e istmo aórtico (r=0,678; P=0,001); Aorta ascendente e arco aórtico (r=0,444; P = 0,044). Não existe diferença significativa no tamanho dos miócitos (coloração HE) entre o grupo AMAA e o grupo EMAA/EMEA (P=0,427), porém existe diferença significativa entre AMAA e controle (P=0,011) e entre EMAA/EMEA e controle (P=0,023). O percentual de colágeno (coloração de picro-sírius) é significantemente diferente entre os três grupos (P=0,0001) e o grupo AM é o que contém maior percentual de colágeno. Conclusões: 1. Na SCEH os corações com EM apresentam significativamente coronárias tortuosas e dominância coronariana esquerda em comparação com AM; 2. No grupo AM encontramos correlação significativa entre o diâmetro da aorta descendente e arco aórtico e entre aorta descendente e istmo aórtico; 3. No grupo EM, há correlação significativa entre as seguintes variáveis: anel mitral e comprimento via de entrada do ventrículo direito, anel mitral e istmo aórtico, cavidade do ventrículo esquerdo e aorta ascendente, arco aórtico e istmo aórtico e arco aórtico e aorta ascendente; 4. Há hipertrofia dos miócitos nos espécimes com AM e EM em comparação com o grupo controle; 5. Na SCEH o percentual de colágeno é superior ao grupo controle; 6. O grupo AM tem maior percentual de colágeno que o grupo EM / Introduction: Hypoplastic left heart syndrome (HLHS) comprises a spectrum of cardiac malformations characterized by a significant underdevelopment of the left heart-aorta complex, which remains a challenge despite the progress of treatment. The objective of this work is to identify morphological and histological differences in hearts with atresia and mitral stenosis with HLHS. Methods: 33 hearts with HLHS divided into two groups, mitral atresia (AM) and mitral stenosis (MS) and nine normal hearts (control),obtained at autopsy, submitted to morphological analysis of aortic segments, mitral and tricuspid valves, atrial septum, infarction, and ventricular cavities and histological study with Hematoxylin/eosin and picro sírius stain. Results: There were nine specimens with aortic atresia and mitral atresia (AMAA), 27.2%; thirteen with atresia Mitral and Aortic Stenosis (AMEA), 39.3% and eleven with Mitral Stenosis and Aortic Stenosis (EMEA) 33.3%. There is a significant association of prevalence of coronary tortuous in the MS group (x2 = 4.911, P=0.027) and left coronary dominance in 75% of cases of MS, with a significant difference between the two groups (x2 2 = 9.298, P=0,01). In the AM group we found a significant correlation between the descending aorta and aortic arch (r=0.692, P=0.039) and between the descending aorta and aortic isthmus (r =0.796, P=0.01). In the MS group there was a significant correlation between variables: mitral ring and length inlet right ventricle (r= 0.523, P=0.045), mitral and aortic isthmus (r=0.692, P=0.003), left ventricular cavity and ascending aorta (r=0.643, P=0.01); Aortic arch and aortic isthmus (r=0.678, P=0.001), ascending aorta and aortic arch (r=0.444, P=0.044).There is no significant difference in the size of myocites (HE staining) between the group and the group AMAA EMAA / EMEA (P = 0.427), but we found significant difference between AMAA and control (P = 0.011) and between EMAA / EMEA and control (P=0.023). The percentage of collagen (picrosirius staining) is different between the three groups (P=0.0001) and AM is the group that contains a higher percentage of collagen. Conclusions: 1. In HLHS hearts with MS present significant tortuous coronary and left coronary dominance compared with AM; 2. In the AM group there is a significant correlation between the diameter of the descending aorta and aortic arch and descending aorta and across the aortic isthmus; 3. In the MS group, there was significant correlation between the following variables: length and mitral inflow tract, mitral and aortic isthmus, left ventricular cavity and the ascending aorta, aortic arch and isthmus aorta and aortic arch and ascending aorta; 4. There is myocite hypertrophy in specimens with AM and EM compared with control; 5. In the HSLS collagen percentage is higher than control; 6. The AM group has a higher percentage of collagen than the EM group
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Recruitment, single ventricular palliation, and complex biventricular repair for patients with Hypoplastic Left Heart SyndromeWu, Vivian 18 June 2019 (has links)
BACKGROUND: Hypoplastic Left Heart Syndrome is a congenital birth defect that is defined by underdevelopment of the left heart during pregnancy. This is especially dangerous as the left heart holds the systemic flow of blood- the oxygenated blood. Not enough oxygen throughout the whole body causes cyanosis, which symptoms include bluish discoloration of the skin or mucous membrane due to low oxygen saturation. Single Ventricle Palliation followed by Biventricular Conversion is the most common surgical procedural pathway to correct this defect. The goal is to convert from a single ventricle circulation during single ventricle palliation to biventricular circulation via biventricular conversion, which is the normal heart anatomy. Single Ventricle Pallation consists of three stages: Stage 1 Norwood Procedure, Bidirectional Glenn, and Fontan. Biventricular Conversion can be performed after any of the three stages. In addition, further compromise of the left ventricle includes other factors such as a thickening of fibroblast-like cells on the endocardial layer called endocardial fibroelastosis. Therefore, additional surgical procedures, also known as recruitment procedures, combat these problems. It is critical to find a correlation between a specific procedure and post surgery success in left ventricle growth and function for these patients.
OBJECTIVES: Patients with Hypoplastic Left Heart Syndrome at Boston Children’s Hospital have undergone single ventricle palliation with some patients proceeding to biventricular conversion. This study aimed to study the palliation stages individually and recruitment procedures (specifically endocardial fibroelastosis resection) on the effect of left ventricle growth.
METHODS: Patients with Hypoplastic Left Heart Syndrome were studied retrospectively (before 2014) and prospectively (after 2014 until December 1, 2018). Single Ventricle Palliation and Biventricular Conversion were analyzed via descriptional analysis with evidence of left ventricular growth measured by left ventricular end diastolic volume and respective z-scores. Z-scores were used to standardize end diastolic volume values across variability in age, weight, and height.
RESULTS: A total of 55 patients underwent single ventricle palliation and 39 ended with biventricular circulation via biventricular conversion. Overall, there was a 9.29 ml increase in end diastolic volume between Bidirectional Glenn and Fontan and a 0.795 increase in end diastolic volume z-score between Fontan and Biventricular Conversion. Next, those who did not have recruitment procedures experienced a 135.6%, 48.8%, and 0% growth at Stage 1, Bidirectional Glenn, and Fontan, respectively, before directly proceeding to biventricular conversion. Those with recruitment experienced a 44.5%, 90.4%, and 83.0% growth at Stage 1, Bidirectional Glenn, and Fontan, respectively, before directly proceeding to biventricular conversion. Finally, there was a 50.2% and 62.3% in left ventricular growth at Bidirectional Glenn and Fontan, respectively, after endocardial fibroelastosis resection compared to only a 6.9% growth at Stage 1.
CONCLUSION: Bidirectional Glenn was the most effective palliation stage for left ventricular growth. Recruitment in patients at this stage was associated with growth that exceeds those who did not have recruitment. This stage also best demonstrates the ability and success of growing a small ventricle to be adequate for biventricular conversion. Left ventricular growth at Fontan circulation holds promising results that are a point of interest for more studies. Endocardial Fibroelastosis resection is more effective on left ventricular growth at Bidirectional Glenn and Fontan compared to Stage 1.
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Prognostic Stratification in Patients with Left Heart Disease : A Machine Learning Approach / Prognostisk stratifiering hos patienter med vänstersidig hjärtsvikt : En maskininlärningsmetodSaleh, Mariam January 2024 (has links)
Left heart disease often results in left heart failure and right ventricular dysfunction which is challenging to diagnose with traditional diagnostic approaches. To address this a novel empirical 4-point right ventricular dysfunction score was created at Sahlgrenska University Hospital to overcome the limitations of single variables for diagnosing right ventricular dysfunction. In this study, we used machine learning, more specifically XGBoost coupled with interactive machine learning to develop four different models for predicting death or receiving a left ventricular assist device in patients with left heart disease (n=486). Features were selected from the dataset using recursive feature elimination with the default number of features. The initial model with 29 features, called the baseline model served as the foundation of the three additional models, each adjusted based on feedback from a clinician. The first step of feedback included removing features due to high correlation, creating a modified model with 12 features, the second step was to use 12 well-known characteristics of left and right ventricular dysfunction creating an empirical model, and adjusting the prediction threshold from 50% to 60%. The third step was to reduce the number of features to 5 based on empirical grounds. The models were compared to the right ventricular dysfunction score using the metrics area under the curve, f1 score, positive likelihood ratio, and negative likelihood ratio. The predictive efficacy of the machine learning models was superior compared to the right ventricular dysfunction score. The results also indicated that the models did neither improve nor deteriorate when reducing the number of features. However, insufficient accuracy indicates that none of the machine learning models are clinically viable. These results show the potential of machine learning in enhancing prognostic stratification in patients with left heart disease although further refinement is necessary for clinical use. / Vänstersidig hjärtsjukdom resulterar ofta i vänstersidig hjärtsvikt och högerkammarsvikt vilket är utmanade att diagnostisera med traditionella diagnostiska metoder. För att komma undan med begränsningen med enskilda variabler för att diagnostisera högerkammarsvikt skapades ett 4 poängs högerkammarsvikt score vid Sahlgrenska Universitetssjukhuset. I denna studie användes en XGBoost-algoritm kombinerat med interaktiv maskininlärning för att utveckla fyra olika prediktions modeller för att förutsäga dödlighet eller risken att få en mekanisk hjärtpump för vänster kammare hos patienter med vänster hjärtsvikt (n=486). Variabler valdes från datamängden med hjälp av rekursiv funktionseliminering med ett standardantal variabler. Den initiala modellen med 29 variabler kallades baslinjemodellen och fungerade som grunden för de tre ytterligare modellerna som justerades baserat på klinikerns feedback. Det först steget inkluderade att ta bort variabler med inbördes hög korrelation och vi skapade en modifierad modell med 12 variabler. I det andra steget i den empiriska modellen använde vi 12 kända egenskaperna vid vänsterkammar- och högerkammarsvikt och för båda justerades tröskelvärdet för prediktion från 50% till 60%. I ett tredje steg skapade vi en förenklad modell med 5 variabler ut ifrån klinisk grund. Modellerna jämfördes med höger hjärtsvikts 4 poängskalan med hjälp av mätvariablerna area under kurvan, f1-poäng, positivt sannolikhets ratio och negativt sannolikhets ratio. Detta avslöjade att maskininlärnings modellerna hade bättre prediktiv förmåga än 4-poängs högerkammarsvikt score. Dessutom visade resultatet att modellerna inte försämrades eller förbättrades när variabler valdes bort eller när nya modeller skapades på klinisk grund. Dock hade maskininlärnings modellerna otillräcklig noggrannhet för klinisk användning.
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Contribution à l'étude par TDM du retentissement sur le coeur gauche de la pathologie pulmonaire. / Contribution in computed tomography of impact on the left heart of pulmonary diseases.Cassagnes, Lucie 16 December 2016 (has links)
La pathologie pulmonaire et la pathologie cardiaque interagissent et le bloc “Cœur- poumon” est à considérer comme une seule et même entité en imagerie: la lecture du cœur, des vaisseaux, des poumons et du médiastin doit être globale et intégrée, quelle que soit la modalité d’imagerie. Nous avons pu ainsi illustrer la contribution de la TDM dans l’évaluation de la prévalence de la pathologie coronarienne asymptomatique au cours de la fibrose pulmonaire idiopathique, l’analyse du volume de l’oreillette gauche au cours des BPCO, la corrélation entre volume pulmonaire hypoperfusé et le rapport VD/VG, et l’évaluation de l’envahissement cardiaque au cours des néoplasies pulmonaires. Les avancées techniques en scannographie nous permettent désormais d’approcher outre la morphologie le versant fonctionnel, notamment par l’évaluation de la fonction cardiaque, de la perfusion pulmonaire, en attendant le développement en routine clinique de l’approche par TDM de la fonction de ventilation. Notre thèse avait pour ambition de contribuer modestement à la promotion d’une approche morphologique et fonctionnelle intégrée de l’imagerie du cœur, des vaisseaux thoraciques et du poumon, dont les bénéfices cliniques nous apparaissent quotidiens et dont l’enseignement nous apparait indissociable. / Pulmonary and cardiac pathology interact and the « heart-lung » bloc is to consider as one and same entity in imaging: heart, vessels, lungs and mediastinum analysis must be global and integrated, whatever imaging modality.In this work, we have illustrated computed tomography contribution in: evaluating asymptomatic coronary disease in cystic fibrosis pathology, left atrial volume in COPD patients, correlation of hypo perfused lung volume and RV/LV ratio, and cardiac invasion evaluation in broncho-pulmonary neoplasm.Computed tomography technological advances allow us to evaluate morphology and functional side, in evaluating cardiac function, pulmonary perfusion, waiting for the development of pulmonary ventilation in routine. Our work contributes to the development of a morphological and functional approach in heart, great vessels and lung imaging.
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