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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 role of bone morphogenic proteins in human aortic valvular endothelial cells

Ankeny, Randall Francis 01 April 2010 (has links)
In the United States alone, there are nearly 49,000 aortic valvular repairs or replacements each year, and this number is expected to rise. Unlike atherosclerosis, the molecular mechanisms contributing to this side-dependent disease development are limited, which contributes to the lack of therapeutic treatments. Once clinically manifested, options for treatment are limited to valvular replacement or repair. Therefore understanding the mechanobiology and cellular responses in aortic valves may provide important information for disease development and possible biomarkers or therapeutic treatments. Aortic valve disease occurs on one side of the valvular leaflet. The fibrosa side, which faces the aorta, is prone to disease development, while the ventricularis remains relatively unaffected. The hemodynamics is hypothesized to play a role in side dependent disease formation. The fibrosa endothelium is exposed to oscillatory flow while the ventricularis endothelium is exposed to a pulsatile unidirectional flow. Previous work by our group has shown that bone morphogenic protein-4 is a mechanosensitve inflammatory cytokine in the vasculature. In the following study, we proposed that mechanosensitive bone morphogenic proteins play a role in side specific aortic valve disease. Recently, the bone morphogenic proteins (BMPs) have been found in calcified human aortic valves. Furthermore, BMP-4 in vascular endothelial cells is increased by oscillatory shear stress. However, the role of the BMPs in aortic valve endothelial cells and their contribution to aortic valve calcification remains unstudied. Therefore, the overall objective of this dissertation was to investigate how disease and hemodynamics affects the BMP pathway and inflammation in human aortic valvular endothelial cells. By understanding how the bone morphogenic proteins are regulated and what roles they play in aortic valve disease, we will have better insight into endothelial cell regulation and contribution in aortic valve pathology. The central hypothesis of this project was that oscillatory flow conditions on the fibrosa side of the aortic valve stimulate endothelial cells to produce BMP-4, which then activates an inflammatory response leading to accumulation of inflammatory cells, calcification, and ultimately valve impairment. This hypothesis was tested through three specific aims using calcified human aortic valves, non-calcified human aortic valves, and side-specific human aortic valve endothelial cells. We first worked to establish the importance of the BMPs in the aortic valvular endothelium by looking at two populations of aortic valves: 1) calcified human aortic valves were obtained from patients undergoing valve replacement, and 2) non-calcified valves were obtained from recipient hearts of patients undergoing heart transplantation. Using immunohistochemical techniques, we examined the BMPs, BMP antagonists, and SMADs. Surprisingly, we identified that the ventricularis endothelium had higher BMP expression in both calcified and non-calcified human aortic valves. Furthermore, no disease-dependent BMP expression was detected. Next, we examined the BMP antagonists and found that there was robust BMP antagonist expression in the ventricularis endothelium and very low expression in the fibrosa endothelium. Finally, to determine if the BMP pathway was activated, we stained for the canonical BMP signaling molecule phosphorylated-SMAD 1/5/8 and found increased staining in the endothelium of calcified human aortic valves. Furthermore, a significant increase in SMAD 1/5/8 phosphorylation was seen in the endothelium of calcified fibrosa when compared to the non-calcified fibrosa. Finally, inhibitory SMAD 6 was significantly increased in the ventricularis endothelium of non-calcified human aortic valves. These findings suggest that preferential activation of BMP pathways, controlled by the balance between the BMPs and their inhibitors, play an important role in side-dependent calcification of human AVs. We next wanted to examine the role of shear stress in BMP regulation, but before doing so, we needed to examine the endothelial response to fluid shear stress to validate the phenotype of our isolated human aortic valve endothelial cells. KLF2 and eNOS expression in vascular endothelial cells has been shown to be increased by laminar flow and to have anti-inflammatory effects by decreasing VCAM-1 levels. Conversely, oscillatory shear stress has been shown to increase NF-kappa B translocation and increase ICAM-1 and E-selectin. We found laminar shear stress causes human aortic valve endothelial cells align parallel to flow and have robust increases of KLF2 and eNOS and decreases in VCAM-1 levels; however, laminar shear-treated cells had similar levels of NF-kappa B activation as oscillatory treated cells while ICAM-1 and E-selectin was not affected by shear stress. In contrast, oscillatory shear had higher levels of monocytes bound which may be due to eNOS's protective effects under laminar shear and robust VCAM-1 expression in oscillatory shear. These studies suggest differential regulation of human aortic valvular endothelial cells than published reports on human aortic endothelial cells which adds to the growing evidence that valvular endothelial cells are phenotypically different than vascular endothelial cells. After verifying the shear response of our endothelial cells, we next determined the shear response of the BMPs and BMP antagonists and described BMPs' effect on inflammation. Previously, BMP-4 has been shown in vitro and in vivo to be increased in endothelial cells exposed to oscillatory flow, while the closely-related BMP-2 has not been shown to be shear sensitive. In this study we have found that BMPs -2 and -4 are shear sensitive while BMP-6 is not. Furthermore, we have found that follistatin is decreased by laminar flow only in the ventricularis, while MGP1 is decreased in the fibrosa valvular endothelial cells under both oscillatory and laminar flow. Finally, incubation with noggin did not affect monocyte adhesion after shear, suggesting differential regulation of inflammation in human aortic valvular endothelial cells. By addressing the specific aims of this project, we have investigate disease- and side-dependent valvular endothelial BMP expression in vivo, shear regulation of valvular endothelial inflammation in vitro, and shear regulation of valvular endothelial BMP expression in vitro. Our results suggest that the BMP pathway is playing a role in side specific aortic valve disease development; however, regulation of the BMPs does not appear to be shear regulated in vivo. Other factors that may be affecting BMP production include including pulsatile pressures, bending stresses, cyclic stretch, and humeral stimuli present in the blood of the patients. However, in vitro we have found BMPs -2 and -4 to be shear-regulated in human aortic valvular endothelial cells. Shear-induced inflammation in human aortic valve endothelial cells seems to be VCAM-1-dependent, and BMP-independent. Finally, by identifying factors that are modulated in calcific- and shear-dependent processes, new targets for the early detection of aortic valve disease can be determined and new therapeutics to slow or stop the progression of aortic valve disease may be discovered.
22

Prótese valvar mitral : 20 anos de seguimento de uma amostra de pacientes operados no Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brasil

Ribeiro, Angela Henrique Silva January 2013 (has links)
Este estudo avalia mortalidade, reoperação e eventos hemorrágicos em pacientes submetidos à cirurgia para troca valvar mitral utilizando substituto biológico ou mecânico. O delineamento do estudo foi do tipo coorte histórica. Entre todos os registros, foram selecionados 352 prontuários de pacientes submetidos à cirurgia para troca valvar mitral entre 1990 e 2008, que tiveram seguimento mínimo de 5 e máximo de 23 anos. Para avaliar o tempo de sobrevida, a probabilidade de reoperação e de eventos hemorrágicos, foi utilizada a curva de Kaplan-Meier. Foi aplicado, para comparar as curvas entre os grupos, o teste qui-quadrado de Log-rank. A análise multivariada de Regressão de Cox foi utilizada para identificar preditores independentes de mortalidade, reoperação e eventos hemorrágicos. A sobrevivência em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 87,7%, 74,2%, 69,3% e 69,3% e, para substituto biológico, foi de 87,6%, 71,0%, 64,2%, e 56,6%, respectivamente. Não houve diferença significativa entre a mortalidade entre os dois grupos (p=0,38). Na análise multivariada, os fatores associados com o óbito foram: idade, eventos hemorrágicos e insuficiência renal. A probabilidade de permanecer livre de reoperação em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 94,4%, 92,7%, 92,7% e 92,7% e, para bioprótese, foi de 95,9%, 86,4%, 81,2% e 76,5%, respectivamente (p=0.073), com uma incidência significativamente maior de reoperação para bioprótese (p=0,008). Os fatores associados com reoperação foram: sexo masculino, diâmetro da prótese e endocardite. A probabilidade de permanecer livre de eventos hemorrágicos em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 95,0%, 91,0%, 89,6% e 89,6% e, para bioprótese, foi de 96,9%, 94,0%, 94,0% e 94,0%, respectivamente (p=0,267). Os fatores associados com eventos hemorrágicos foram: IMC (índice de massa corporal) superior à 30 kg/m2, doença pulmonar obstrutiva crônica, tempo de ventilação mecânica na Unidade de Tratamento Intensivo superior a 30 dias e presença insuficiência mitral. Os autores concluíram que: 1) a mortalidade foi estatisticamente semelhante entre os dois grupos no seguimento; 2) houve tendência maior à reoperação no grupo com bioprótese; 3) após 10 anos de seguimento, a probabilidade de permanecer livre de reoperação não mudou para pacientes com substitutos valvares mecânicos; 4) a probabilidade de permanecer livre de eventos hemorrágicos não mudou após 10 anos de seguimento para portadores de biopróteses; 5) as características basais dos pacientes foram os maiores determinantes de mortalidade tardia após a cirurgia; 6) o tipo de prótese não foi fator preditor independente associado a nenhum dos desfechos avaliados na análise multivariada. / This study assessed mortality, reoperation and bleeding events in patients who underwent mitral valve replacement surgery with a biological or mechanical substitute. This was a historical cohort study. In total, 352 inpatients clinical health records who underwent mitral valve replacement surgery between 1990 and 2008 with 5 to 23 years of follow-up were selected. A Kaplan-Meier curve was used to evaluate the survival time, the probability of reoperation and bleeding events. A log-rank chi-square test was applied to compare the curves between groups. Multivariate Cox regression analysis was used to identify independent predictors of mortality, reoperation and bleeding events. The 5, 10, 15 and 20 year survival rates after surgery using a mechanical substitute were 87.7%, 74.2%, 69.3% and 69.3%, respectively, while the survival rates after surgery with a biological substitute were 87.6%, 71.0%, 64.2% and 56.6%, respectively. There was no significant difference in mortality between the two groups (p = 0.38). In the multivariate analysis, the factors associated with death were age, bleeding events and renal failure. The probabilities of being free of reoperation at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 94.4%, 92.7%, 92.7% and 92.7%, respectively, while after surgery with a bioprosthesis, they were 95.9%, 86.4%, 81.2% and 76.5%, respectively (p = 0.073); therefore, there was a significantly higher incidence of reoperation for patients receiving a bioprosthesis (p = 0.008). The factors associated with reoperation were male gender, diameter of the prosthesis and endocarditis. The probabilities of remaining free of bleeding events at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 95.0%, 91.0%, 89.6% and 89.6, respectively, while after surgery with a bioprosthesis, they were 96.9%, 94.0%, 94.0% and 94.0%, respectively (p = 0.267). The factors associated with bleeding events were BMI (body mass index) greater than 30 kg/m2, chronic obstructive pulmonary disease, mechanical ventilation at an Intensive Care Unit for longer than 30 days and mitral regurgitation. The authors concluded that: 1) mortality during follow-up was statistically similar in both groups; 2) there was a greater tendency to reoperation in the bioprosthesis group; 3) the probability of survival free from reoperation did not change for patients with mechanical valves after 10 years’ follow-up; 4) the probability of survival free from bleeding events did not change after 10 years’ follow-up for bioprostheses patients; 5) patients’ baseline characteristics were the greatest determinants of late mortality after mitral valve replacement surgery; 6) the type of prosthesis fitted was not an independent predictive factor of any of the outcomes analyzed in the multivariate analysis.
23

Prótese valvar mitral : 20 anos de seguimento de uma amostra de pacientes operados no Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brasil

Ribeiro, Angela Henrique Silva January 2013 (has links)
Este estudo avalia mortalidade, reoperação e eventos hemorrágicos em pacientes submetidos à cirurgia para troca valvar mitral utilizando substituto biológico ou mecânico. O delineamento do estudo foi do tipo coorte histórica. Entre todos os registros, foram selecionados 352 prontuários de pacientes submetidos à cirurgia para troca valvar mitral entre 1990 e 2008, que tiveram seguimento mínimo de 5 e máximo de 23 anos. Para avaliar o tempo de sobrevida, a probabilidade de reoperação e de eventos hemorrágicos, foi utilizada a curva de Kaplan-Meier. Foi aplicado, para comparar as curvas entre os grupos, o teste qui-quadrado de Log-rank. A análise multivariada de Regressão de Cox foi utilizada para identificar preditores independentes de mortalidade, reoperação e eventos hemorrágicos. A sobrevivência em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 87,7%, 74,2%, 69,3% e 69,3% e, para substituto biológico, foi de 87,6%, 71,0%, 64,2%, e 56,6%, respectivamente. Não houve diferença significativa entre a mortalidade entre os dois grupos (p=0,38). Na análise multivariada, os fatores associados com o óbito foram: idade, eventos hemorrágicos e insuficiência renal. A probabilidade de permanecer livre de reoperação em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 94,4%, 92,7%, 92,7% e 92,7% e, para bioprótese, foi de 95,9%, 86,4%, 81,2% e 76,5%, respectivamente (p=0.073), com uma incidência significativamente maior de reoperação para bioprótese (p=0,008). Os fatores associados com reoperação foram: sexo masculino, diâmetro da prótese e endocardite. A probabilidade de permanecer livre de eventos hemorrágicos em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 95,0%, 91,0%, 89,6% e 89,6% e, para bioprótese, foi de 96,9%, 94,0%, 94,0% e 94,0%, respectivamente (p=0,267). Os fatores associados com eventos hemorrágicos foram: IMC (índice de massa corporal) superior à 30 kg/m2, doença pulmonar obstrutiva crônica, tempo de ventilação mecânica na Unidade de Tratamento Intensivo superior a 30 dias e presença insuficiência mitral. Os autores concluíram que: 1) a mortalidade foi estatisticamente semelhante entre os dois grupos no seguimento; 2) houve tendência maior à reoperação no grupo com bioprótese; 3) após 10 anos de seguimento, a probabilidade de permanecer livre de reoperação não mudou para pacientes com substitutos valvares mecânicos; 4) a probabilidade de permanecer livre de eventos hemorrágicos não mudou após 10 anos de seguimento para portadores de biopróteses; 5) as características basais dos pacientes foram os maiores determinantes de mortalidade tardia após a cirurgia; 6) o tipo de prótese não foi fator preditor independente associado a nenhum dos desfechos avaliados na análise multivariada. / This study assessed mortality, reoperation and bleeding events in patients who underwent mitral valve replacement surgery with a biological or mechanical substitute. This was a historical cohort study. In total, 352 inpatients clinical health records who underwent mitral valve replacement surgery between 1990 and 2008 with 5 to 23 years of follow-up were selected. A Kaplan-Meier curve was used to evaluate the survival time, the probability of reoperation and bleeding events. A log-rank chi-square test was applied to compare the curves between groups. Multivariate Cox regression analysis was used to identify independent predictors of mortality, reoperation and bleeding events. The 5, 10, 15 and 20 year survival rates after surgery using a mechanical substitute were 87.7%, 74.2%, 69.3% and 69.3%, respectively, while the survival rates after surgery with a biological substitute were 87.6%, 71.0%, 64.2% and 56.6%, respectively. There was no significant difference in mortality between the two groups (p = 0.38). In the multivariate analysis, the factors associated with death were age, bleeding events and renal failure. The probabilities of being free of reoperation at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 94.4%, 92.7%, 92.7% and 92.7%, respectively, while after surgery with a bioprosthesis, they were 95.9%, 86.4%, 81.2% and 76.5%, respectively (p = 0.073); therefore, there was a significantly higher incidence of reoperation for patients receiving a bioprosthesis (p = 0.008). The factors associated with reoperation were male gender, diameter of the prosthesis and endocarditis. The probabilities of remaining free of bleeding events at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 95.0%, 91.0%, 89.6% and 89.6, respectively, while after surgery with a bioprosthesis, they were 96.9%, 94.0%, 94.0% and 94.0%, respectively (p = 0.267). The factors associated with bleeding events were BMI (body mass index) greater than 30 kg/m2, chronic obstructive pulmonary disease, mechanical ventilation at an Intensive Care Unit for longer than 30 days and mitral regurgitation. The authors concluded that: 1) mortality during follow-up was statistically similar in both groups; 2) there was a greater tendency to reoperation in the bioprosthesis group; 3) the probability of survival free from reoperation did not change for patients with mechanical valves after 10 years’ follow-up; 4) the probability of survival free from bleeding events did not change after 10 years’ follow-up for bioprostheses patients; 5) patients’ baseline characteristics were the greatest determinants of late mortality after mitral valve replacement surgery; 6) the type of prosthesis fitted was not an independent predictive factor of any of the outcomes analyzed in the multivariate analysis.
24

Prótese valvar mitral : 20 anos de seguimento de uma amostra de pacientes operados no Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brasil

Ribeiro, Angela Henrique Silva January 2013 (has links)
Este estudo avalia mortalidade, reoperação e eventos hemorrágicos em pacientes submetidos à cirurgia para troca valvar mitral utilizando substituto biológico ou mecânico. O delineamento do estudo foi do tipo coorte histórica. Entre todos os registros, foram selecionados 352 prontuários de pacientes submetidos à cirurgia para troca valvar mitral entre 1990 e 2008, que tiveram seguimento mínimo de 5 e máximo de 23 anos. Para avaliar o tempo de sobrevida, a probabilidade de reoperação e de eventos hemorrágicos, foi utilizada a curva de Kaplan-Meier. Foi aplicado, para comparar as curvas entre os grupos, o teste qui-quadrado de Log-rank. A análise multivariada de Regressão de Cox foi utilizada para identificar preditores independentes de mortalidade, reoperação e eventos hemorrágicos. A sobrevivência em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 87,7%, 74,2%, 69,3% e 69,3% e, para substituto biológico, foi de 87,6%, 71,0%, 64,2%, e 56,6%, respectivamente. Não houve diferença significativa entre a mortalidade entre os dois grupos (p=0,38). Na análise multivariada, os fatores associados com o óbito foram: idade, eventos hemorrágicos e insuficiência renal. A probabilidade de permanecer livre de reoperação em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 94,4%, 92,7%, 92,7% e 92,7% e, para bioprótese, foi de 95,9%, 86,4%, 81,2% e 76,5%, respectivamente (p=0.073), com uma incidência significativamente maior de reoperação para bioprótese (p=0,008). Os fatores associados com reoperação foram: sexo masculino, diâmetro da prótese e endocardite. A probabilidade de permanecer livre de eventos hemorrágicos em 5, 10, 15 e 20 anos após cirurgia utilizando substituto mecânico foi de 95,0%, 91,0%, 89,6% e 89,6% e, para bioprótese, foi de 96,9%, 94,0%, 94,0% e 94,0%, respectivamente (p=0,267). Os fatores associados com eventos hemorrágicos foram: IMC (índice de massa corporal) superior à 30 kg/m2, doença pulmonar obstrutiva crônica, tempo de ventilação mecânica na Unidade de Tratamento Intensivo superior a 30 dias e presença insuficiência mitral. Os autores concluíram que: 1) a mortalidade foi estatisticamente semelhante entre os dois grupos no seguimento; 2) houve tendência maior à reoperação no grupo com bioprótese; 3) após 10 anos de seguimento, a probabilidade de permanecer livre de reoperação não mudou para pacientes com substitutos valvares mecânicos; 4) a probabilidade de permanecer livre de eventos hemorrágicos não mudou após 10 anos de seguimento para portadores de biopróteses; 5) as características basais dos pacientes foram os maiores determinantes de mortalidade tardia após a cirurgia; 6) o tipo de prótese não foi fator preditor independente associado a nenhum dos desfechos avaliados na análise multivariada. / This study assessed mortality, reoperation and bleeding events in patients who underwent mitral valve replacement surgery with a biological or mechanical substitute. This was a historical cohort study. In total, 352 inpatients clinical health records who underwent mitral valve replacement surgery between 1990 and 2008 with 5 to 23 years of follow-up were selected. A Kaplan-Meier curve was used to evaluate the survival time, the probability of reoperation and bleeding events. A log-rank chi-square test was applied to compare the curves between groups. Multivariate Cox regression analysis was used to identify independent predictors of mortality, reoperation and bleeding events. The 5, 10, 15 and 20 year survival rates after surgery using a mechanical substitute were 87.7%, 74.2%, 69.3% and 69.3%, respectively, while the survival rates after surgery with a biological substitute were 87.6%, 71.0%, 64.2% and 56.6%, respectively. There was no significant difference in mortality between the two groups (p = 0.38). In the multivariate analysis, the factors associated with death were age, bleeding events and renal failure. The probabilities of being free of reoperation at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 94.4%, 92.7%, 92.7% and 92.7%, respectively, while after surgery with a bioprosthesis, they were 95.9%, 86.4%, 81.2% and 76.5%, respectively (p = 0.073); therefore, there was a significantly higher incidence of reoperation for patients receiving a bioprosthesis (p = 0.008). The factors associated with reoperation were male gender, diameter of the prosthesis and endocarditis. The probabilities of remaining free of bleeding events at 5, 10, 15 and 20 years after surgery using a mechanical substitute were 95.0%, 91.0%, 89.6% and 89.6, respectively, while after surgery with a bioprosthesis, they were 96.9%, 94.0%, 94.0% and 94.0%, respectively (p = 0.267). The factors associated with bleeding events were BMI (body mass index) greater than 30 kg/m2, chronic obstructive pulmonary disease, mechanical ventilation at an Intensive Care Unit for longer than 30 days and mitral regurgitation. The authors concluded that: 1) mortality during follow-up was statistically similar in both groups; 2) there was a greater tendency to reoperation in the bioprosthesis group; 3) the probability of survival free from reoperation did not change for patients with mechanical valves after 10 years’ follow-up; 4) the probability of survival free from bleeding events did not change after 10 years’ follow-up for bioprostheses patients; 5) patients’ baseline characteristics were the greatest determinants of late mortality after mitral valve replacement surgery; 6) the type of prosthesis fitted was not an independent predictive factor of any of the outcomes analyzed in the multivariate analysis.
25

Aortic root reinforcement in aortic valve endocarditis with annular abscess: The Calamari procedure

Petrov, Asen, Diab, Abdel‐Hannan, Taghizadeh‐Waghefi, Ali, Wilbring, Manuel, Alexiou, Konstantin, Matschke, Klaus Erhard, Tugtekin, Sems‐Malte, Kappert, Utz 11 June 2024 (has links)
Treatment of infective endocarditis can often prove challenging due to its wide range of anatomical presentations. When complicated by an aortic root abscess, patients may require extensive root surgery, which on its own leads to a worse outcome. We present our experience with a surgical technique for reinforcing the aortic annulus with a ring from a Dacron aortic prosthesis placed in the left ventricular outflow tract to avoid the need for root replacement procedures or patch closures of the defect. The technique described in this paper provides a viable alternative to the standard techniques used for the treatment of annular abscesses in aortic valve endocarditis. Due to the relative simplicity and ease of use, this approach may present a means of reducing operation time and possibly postoperative complications of this severe condition.
26

Die Kontinuität des Brustkorbes als Mobilitätskriterium nach einem konventionellen Aortenklappeneingriff

Teubert, Moritz 12 August 2024 (has links)
Die vorliegende Arbeit untersucht, inwieweit sich minimalinvasive Zugangswege gegenüber der medianen Sternotomie bei isolierten Aortenklappeneingriffen positiv auf die postoperative Schultergelenks- und Schultergürtelmobilität auswirken. Die Beurteilung erfolgt dabei postoperativ primär durch Anwendung des Constant-Murley-Score (CMS). Weiterhin werden der Disabilities of the Arm, Shoulder and Hand Fragebogen (DASH) sowie Untersuchungen von Gelenkbeweglichkeiten und Muskelfunktion (Verlängerbarkeit und Kraft) durchgeführt. Bis dato existiert kein gesondertes Testinstrument zur Beurteilung der funktionellen Einheit Schultergürtel / Schultergelenk in der Herzchirurgie. Existierende Untersuchungen deuten jedoch darauf hin, dass größere, insbesondere herzchirurgische Eingriffe sowohl lokal als auch systemisch Einfluss auf die Funktionalität von Muskulatur haben. Sei es durch direkte Affektion oder aufgrund postoperativer Immobilisation. Für den DASH gibt es ebenfalls bereits veröffentlichte Ergebnisse, die eine Verschlechterung der Funktion der oberen Extremität nach einer Herz-OP zeigen. Bei Betrachtung der Ergebnisse des CMS in dieser Arbeit haben die Patienten nach minimalinvasivem Aortenklappenersatz sowohl rechts (78,9±10,4 minimalinvasiv vs. 60,8±8,6 konventionell, p<0,01) als auch links (80,0±8,0 minimalinvasiv vs. 61,8±5,6 konventionell, p<0,01) eine signifikant bessere Schulterfunktion als nach medianer Sternotomie. Auch die Ergebnisse des DASH zeigen nach minimalinvasiver Operation eine signifikant bessere Funktion der oberen Extremität (40,9±13,6 minimalinvasiv vs. 62,5±22,1 konventionell, p=0,02). Die Beweglichkeitsuntersuchungen lassen bessere postoperative Ergebnisse bei den minimalinvasiv Operierten, insbesondere für nach vorne gerichteten Bewegungen, wie der Protraktion links (20±2,9° minimalinvasiv vs. 13±5,7° konventionell, p<0,01) und der horizontalen Adduktion rechts (115±9,8° minimalinvasiv vs. 103±9,7° konventionell, p=0,03), erkennen. Muskelverlängerbarkeit und -kraft hingegen offenbaren in diesem Setting keine signifikanten Unterschiede zwischen minimalinvasiver und konventioneller Gruppe. Ein Grund dafür kann unter anderem das lange Untersuchungsintervall postoperativ sein. Aufgrund der kleinen Anzahl eingeschlossener Patienten ist die statistische Aussagekraft dieser Arbeit eingeschränkt. Insgesamt wird jedoch die Annahme unterstützt, dass minimalinvasive Verfahren in der Aortenklappenchirurgie eine bessere Funktion der Schulter postoperativ ermöglichen, als dies durch die mediane Sternotomie der Fall ist. Diese bessere Funktion lässt sich durch etablierte Instrumente wie den Constant-Murley-Score sowie den DASH-Fragebogen darstellen.
27

Análise ecocardiográfica anatômica e funcional intraoperatória da valva mitral em pacientes com prolapso valvar submetidos à valvoplastia cirúrgica: estudo transesofágico bidimensional e tridimensional / Intraoperative anatomic and functional analyses of mitral valve in patients with valve prolapsed submitted to surgical valvuloplasty: a two-dimensional and three-dimensional transesophageal study

Pardi, Mirian Magalhães 01 December 2014 (has links)
Introdução: Embora o papel da ecocardiografia transesofágica (ETE) esteja bem estabelecido na avaliação morfológica e funcional da valva mitral e na seleção dos pacientes com prolapso da valva mitral (PVM) para a cirurgia reparadora, o impacto da ETE tridimensional (3D) no resultado cirúrgico ainda não está bem demonstrado. Os objetivos deste trabalho foram avaliar o valor diagnóstico adicional da ETE 3D em comparação com a técnica bidimensional (2D) e a associação de parâmetros anatômicos tridimensionais com o resultado cirúrgico em pacientes com PVM submetidos à valvoplastia. Métodos: Para a análise comparativa da sensibilidade, especificidade e acurácia diagnóstica entre ETE 2D e 3D, foram incluídos 62 pacientes operados por PVM com insuficiência importante, sendo a inspeção cirúrgica considerada padrão-ouro. Para a análise 3D, foram estudados 54 pacientes submetidos à plástica valvar que foram divididos em 2 grupos de acordo com o grau da insuficiência mitral pós-operatória (grupo 1, insuficiência mitral ausente ou grau I; grupo 2, insuficiência mitral grau II ou III). Foram medidos pela quantificação 3D os seguintes parâmetros anatômicos: diâmetros anteroposterior e intercomissural, altura, circunferência e área do anel mitral; comprimento, área e linha de coaptação das cúspides; volume e altura do prolapso; distância dos músculos papilares à borda da cúspide; e ângulos mitroaórtico e não planar. Para a identificação de variáveis associadas aos grupos de resultados cirúrgicos, foi realizada análise univariada (teste t de Student para as variáveis contínuas e teste qui-quadrado ou o teste de Fisher para as variáveis categóricas), análise multivariada com método de regressão logística e curva ROC para a obtenção do ponto de corte. Resultados: A ETE 2D apresentou maior sensibilidade no diagnóstico de prolapso nos segmentos A2, P1 e P3 que a ETE 3D (p = 0,019, 0,023, 0,012, respectivamente) enquanto que a ETE 3D apresentou maior especificidade no segmento P1 (p = 0,006). Não houve diferença na acurácia diagnóstica ente os dois métodos. A presença de prolapso das duas cúspides (p = 0,041) e a distância do músculo papilar posteromedial à borda da cúspide (p = 0,038) foram maiores no grupo 2. Análise multivariada identificou prolapso das duas cúspides e distância do músculo papilar posteromedial à borda da cúspide maior que 30 mm como fatores associados à insuficiência mitral pós-operatória grau II ou III (p = 0,039 e 0,015, respectivamente), e com risco de 5,3 e 6,3 vezes maior de insuficiência significativa pós-operatória, respectivamente. Conclusões: A ETE 2D e 3D apresentaram acurácia equivalente no diagnóstico de PVM, com maior sensibilidade da ETE 2D no diagnóstico de prolapso nos segmentos A2, P1 e P3, e maior especificidade da ETE 3D no segmento P1. A distância do músculo papilar posteromedial à borda da cúspide obtida pela análise quantitativa 3D e a presença de prolapso das duas cúspides mostraram associação com o grau da insuficiência mitral pós-operatória grau II e III / Background: Although the transesophageal echocardiography (TEE) is well established in the morphological and functional assessment of the mitral valve and in the choice of patients with mitral valve prolapse (MVP) eligible to valvuloplasty, the impact of tridimensional (3D) TEE on surgical results has not been well demonstrated yet. The present study aimed to evaluate the additional diagnostic value of 3D TEE in comparison with bidimensional (2D) technique, as well as the correlation between 3D anatomical parameters and the surgical results in patients with MVP submitted to valvuloplasty. Methods: In order to compare the sensitivity, specificity, and accuracy between 2D and 3D TEE, 62 patients with MVP and severe mitral regurgitation were enrolled; surgical appraisal was considered as the gold-standard. Regarding 3D analysis, 54 patients submitted to valvuloplasty were divided in two groups, according to their postoperative mitral regurgitation grades (group 1, absent or grade I mitral regurgitation; and group 2, grade II or III mitral regurgitation). The following parameters were assessed quantitatively by 3D TEE: anteroposterior diameter, commissural width, height, circumference and area of the mitral ring; anterior and posterior leaflets length, leaflets surface area, coaptation length, volume and height billow; distance from the tip of the anterolateral and posteromedial papillary muscle to leaflet border; non-planar and aortic-mitral angles. Univariate analysis (Student t test for continuous variables and Chi-square or Fischer test to the categorical ones), multivariate and ROC curve analyses were performed to identify the relationship between anatomical parameters and surgical results (p < 5%). Results: 2D TEE showed higher sensitivity to diagnose MVP in A2, P1, and P3 segments, when compared with 3D TEE (p= 0.019, 0.023, and 0.012, respectively), while 3D TEE showed greater specificity to identify P1 segment (p= 0.006). No difference was observed in the accuracy between both methods. The presence of bileaflet prolapse (p= 0.041) and the distance from posteromedial papillary muscle to leaflet border (p= 0.038) were higher in group 2. Multivariate analysis showed that bileaflet prolapse and distance of more than 30 mm from posteromedial papillary muscle to leaflet border were related to grade II or III postoperative mitral regurgitation (p= 0.039 and 0.015, respectively), representing 5.3 and 6.3 more risk of significant mitral regurgitation, respectively. Conclusions: Both 2D TEE and 3D TEE presented similar accuracy in the diagnosis of MVP; 2D TEE showed higher sensitivity to diagnose the prolapse in A2, P1 and P3 segments, while the 3D TEE presented greater specificity to identify the affected P1 segment. The distance from the tip of the posteromedial papillary muscle to the leaflet border quantitatively estimated by 3D TEE and the evidence of bileaflet prolapse showed to be associated to the degree of mitral regurgitation after valvuloplasty
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Chirurgie cardiaque mini-invasive : du concept à l'évaluation d'une instrumentation spécifique / Mini-invasive cardiac surgery : from the concept to the evaluation of dedicated implements

Jegaden, Olivier 17 October 2012 (has links)
Ce travail reprend les études d’évaluation d’une plateforme instrumentale dédiée à la chirurgie mitrale mini-invasive vidéo-assistée, et du télémanipulateur Da Vinci pour la réalisation d’anastomose mammaire interne / IVA à thorax fermé.) Evaluation du Portaclamp. Cette étude clinique a porté sur 20 patients opérés de chirurgie cardiaque sous CEC et a confirmé la simplicité d’utilisation du système, son efficacité et l’absence de morbidité ou complication induite. L’étude chez le porc des effets histologiques sur la paroi de l’aorte des trois clamps (l’endo-clamp, le clamp Chitwood et le Portaclamp) a révélé une atteinte majeure de l’endothélium aortique induite par l’endo-clamp . 2) Evaluation du Portapleg. Le Portapleg est un dispositif auto-suturant de cardioplégie antérograde constitué d’un clip en Nitinol restant implanté sur l’aorte. Une étude sur 20 patients a été rapportée avec comme critère principal le temps de saignement du site de ponction après injection de protamine. Le système a montré son efficacité hémostatique dans tous les cas sans événement secondaire. 3) Evaluation du Mitrax’s. C’est un cône en plastique polymère auto ajustable et auto expansible, qui repousse de façon symétrique et concentrique les parois de l’oreillette. Une étude prospective de son efficacité a été réalisée chez 62 patients opérés de chirurgie mitrale vidéo-assistée de façon consécutive. L’indice de satisfaction a été en moyenne 4.6, témoin d’une exposition optimale de la valve mitrale avec une vision endoscopique ou directe de la valve mitrale jugée excellente. 4) Analyse comparative des techniques mini-invasives de revascularisation de l’IVA par pontage mammaire (Port Access, MIDCAB, TECAB). Cette étude prospective a porté sur 160 patients ; à trois mois, le taux de réintervention sur l’IVA était : PA-CABG, 0% ; MIDCAB, 1.8% ; TECAB, 10% ; p<0.01. A trois ans, les taux actuariels de survie sans réintervention étaient : PA-CABG, 100% ; MIDCAB, 98±5 % ; TECAB, 88±8 % ; p<0.05. / This thesis is based on the evaluation studies of an instrumental platform dedicated to video assisted minimally invasive mitral valve surgery, and of the robotic Da Vinci system in LAD bypass with mammary artery in a closed chest approach. 1) Evaluation of Portaclamp. In 20 patients who underwent cardiac surgery with Portaclamp, a clinical study showed that the clamping system is safe, fast and easy and does not generate undue morbidity. In a pig model, severe lesions of the intima were observed on the clamping spot with the endoclamp, in comparison with Portaclamp and Chitwood clamp. 2) Evaluation of Portapleg. Portapleg is an auto-suturing system dedicated to antegrade cardioplegia delivery, and based on a Nitinol clip left implanted on the aorta. In 20 patients, the closure of the puncture aortic hole and the haemostasis after protamine were obtained in all cases. The procedure did not generate undue morbidity and there was no device-related adverse event. 3) Evaluation of Mitrax’s. The Mitrax’s retractor is a pattern cut polymer sheet, self-expanding and auto-adjusting. The effectiveness of Mitrax’s was evaluated in 62 patients who consecutively underwent a video-assisted mitral valve procedure. The global satisfaction index was 4.6±0.5, demonstrating the effectiveness of the device which provides optimal exposure and excellent direct vision. 4) Comparative analysis of minimally invasive techniques for LAD revascularization with mammary artery graft (Port Access, MIDCAB, TECAB). In a prospective study, 160 patients were included. At 3-month postoperatively, the end-point of LAD reintervention were PA-CABG, 0%; MIDCAB, 1.8%; TECAB, 10%; p=0.01. At 3-year, reintervention-free survival was significantly lower in the TECAB group: PA-CABG, 100% ; MIDCAB, 98±5 % ; TECAB, 88±8 % ; p<0.05.
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Comparação da sobrevida entre indivíduos submetidos à cirurgia para substituição valvar aórtica utilizando próteses mecânicas ou biológicas em uma coorte brasileira

Almeida, Adriana Silveira de January 2010 (has links)
Este estudo avalia mortalidade, eventos hemorrágicos e reoperação em pacientes submetidos à cirurgia para troca valvar aórtica utilizando substituto biológico ou mecânico, com poder de relevância na seleção do tipo da prótese. Foram selecionados, randomicamente, 301 pacientes submetidos à cirurgia para troca valvar aórtica entre 1990 e 2005, com seguimento máximo de 20 anos. A sobrevivência em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 83,9%, 75,4% e 60,2% e, para substituto biológico, foi de 89,3%, 70,4% e 58,4%, respectivamente (p=0,939). Os fatores associados com o óbito foram: idade, obesidade, doença pulmonar, arritmias, eventos hemorrágicos e insuficiência valvar aórtica. A probabilidade livre de reoperação desses pacientes em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 97,9%, 95,8% e 95,8% e, para bioprótese, foi de 94,6%, 91,0% e 83,3%, respectivamente (p=0,057). Os fatores associados com reoperação foram: insuficiência renal, endocardite de prótese e idade. A probabilidade livre de eventos hemorrágicos em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 94,5%, 91,7% e 91,7% e, para bioprótese, foi de 98,6%, 97,8% e 97,8%, respectivamente (p=0,047). Os fatores associados com eventos hemorrágicos foram: insuficiência renal e prótese mecânica. Os autores concluíram que: 1) a mortalidade foi estatisticamente semelhante entre os grupos; 2) as características basais dos pacientes foram os maiores determinantes de mortalidade tardia após a cirurgia; 3) houve uma tendência à reoperação para o grupo com bioprótese; 4) pacientes com prótese mecânica tiveram mais eventos hemorrágicos ao longo do tempo; 5) os dados encontrados no presente estudo são concordantes com a literatura atual. / This paper evaluates mortality, bleeding events and reoperation in patients subjected to surgery for replacement of the aortic valve using a biological or a mechanical substitute, where selection of the type of prosthesis is relevant. Three hundred and one patients who had been subjected to aortic valve replacement surgery between 1990 and 2005, with a maximum follow-up period of 20 years, have been randomly selected. Survival at 5, 10 and 15 years after surgery using a mechanical substitute was 83.9%, 75.4% and 60.2% and, for a biological substitute, was 89.3%, 70.4% and 58.4%, respectively (p=0.939). Factors associated with death were: age, obesity, pulmonary disease, arrhythmia, bleeding and aortic valve failure. The probability free of reoperation for these patients at 5, 10 and 15 years after surgery using a mechanical substitute was 97.9%, 95.8% and 95.8% and, for those using bioprostheses, was 94.6%, 91.0% and 83.3%, respectively (p=0.057). Factors associated with reoperation were: renal failure, prosthesis endocarditis and age. The probability free of bleeding events at 5, 10 and 15 years after surgery using the mechanical substitute was 94.5%, 91.7% and 91.7% and, for bioprostheses, was 98.6%, 97.8% and 97.8%, respectively (p=0.047). Factors associated with bleeding events were: renal failure and mechanical prostheses. The authors have concluded that: 1) mortality was statistically similar in the groups; 2) patient characteristics at baseline were a major determinant of late mortality after surgery; 3) there was a tendency toward reoperation in the bioprostheses group; 4) patients using a mechanical prosthesis had more bleeding events as time passed; 5) the data presented in this paper is in accordance with current literature.
30

Comparação da sobrevida entre indivíduos submetidos à cirurgia para substituição valvar aórtica utilizando próteses mecânicas ou biológicas em uma coorte brasileira

Almeida, Adriana Silveira de January 2010 (has links)
Este estudo avalia mortalidade, eventos hemorrágicos e reoperação em pacientes submetidos à cirurgia para troca valvar aórtica utilizando substituto biológico ou mecânico, com poder de relevância na seleção do tipo da prótese. Foram selecionados, randomicamente, 301 pacientes submetidos à cirurgia para troca valvar aórtica entre 1990 e 2005, com seguimento máximo de 20 anos. A sobrevivência em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 83,9%, 75,4% e 60,2% e, para substituto biológico, foi de 89,3%, 70,4% e 58,4%, respectivamente (p=0,939). Os fatores associados com o óbito foram: idade, obesidade, doença pulmonar, arritmias, eventos hemorrágicos e insuficiência valvar aórtica. A probabilidade livre de reoperação desses pacientes em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 97,9%, 95,8% e 95,8% e, para bioprótese, foi de 94,6%, 91,0% e 83,3%, respectivamente (p=0,057). Os fatores associados com reoperação foram: insuficiência renal, endocardite de prótese e idade. A probabilidade livre de eventos hemorrágicos em 5, 10 e 15 anos após cirurgia utilizando substituto mecânico foi de 94,5%, 91,7% e 91,7% e, para bioprótese, foi de 98,6%, 97,8% e 97,8%, respectivamente (p=0,047). Os fatores associados com eventos hemorrágicos foram: insuficiência renal e prótese mecânica. Os autores concluíram que: 1) a mortalidade foi estatisticamente semelhante entre os grupos; 2) as características basais dos pacientes foram os maiores determinantes de mortalidade tardia após a cirurgia; 3) houve uma tendência à reoperação para o grupo com bioprótese; 4) pacientes com prótese mecânica tiveram mais eventos hemorrágicos ao longo do tempo; 5) os dados encontrados no presente estudo são concordantes com a literatura atual. / This paper evaluates mortality, bleeding events and reoperation in patients subjected to surgery for replacement of the aortic valve using a biological or a mechanical substitute, where selection of the type of prosthesis is relevant. Three hundred and one patients who had been subjected to aortic valve replacement surgery between 1990 and 2005, with a maximum follow-up period of 20 years, have been randomly selected. Survival at 5, 10 and 15 years after surgery using a mechanical substitute was 83.9%, 75.4% and 60.2% and, for a biological substitute, was 89.3%, 70.4% and 58.4%, respectively (p=0.939). Factors associated with death were: age, obesity, pulmonary disease, arrhythmia, bleeding and aortic valve failure. The probability free of reoperation for these patients at 5, 10 and 15 years after surgery using a mechanical substitute was 97.9%, 95.8% and 95.8% and, for those using bioprostheses, was 94.6%, 91.0% and 83.3%, respectively (p=0.057). Factors associated with reoperation were: renal failure, prosthesis endocarditis and age. The probability free of bleeding events at 5, 10 and 15 years after surgery using the mechanical substitute was 94.5%, 91.7% and 91.7% and, for bioprostheses, was 98.6%, 97.8% and 97.8%, respectively (p=0.047). Factors associated with bleeding events were: renal failure and mechanical prostheses. The authors have concluded that: 1) mortality was statistically similar in the groups; 2) patient characteristics at baseline were a major determinant of late mortality after surgery; 3) there was a tendency toward reoperation in the bioprostheses group; 4) patients using a mechanical prosthesis had more bleeding events as time passed; 5) the data presented in this paper is in accordance with current literature.

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