Tesi sul tema "Mitral valve insufficiency"
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Leung, Dominic Y. C. South Western Sydney Clinical School UNSW. "Exercise and left ventricular function in chronic mitral valve insufficiency". Awarded by:University of New South Wales. South Western Sydney Clinical School, 2002. http://handle.unsw.edu.au/1959.4/18808.
Testo completoLi, Xiang-Ning. "Quantitative assessment of mitral regurgitation with three-dimensional doppler echocardiography /". Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/8039.
Testo completoWilkerson, Patrick Wayne. "Quantification of mitral regurgitation using corrected doppler measurements". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17302.
Testo completoPardi, Mirian Magalhães. "Análise ecocardiográfica anatômica e funcional intraoperatória da valva mitral em pacientes com prolapso valvar submetidos à valvoplastia cirúrgica: estudo transesofágico bidimensional e tridimensional". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-02032015-143857/.
Testo completoBackground: 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
Guedes, Marco Antonio Vieira. "Análise morfofuncional cardíaca com o uso da ecocardiografia tridimensional em tempo real em indivíduos submetidos à plastia valvar mitral pela técnica de duplo teflon". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5156/tde-22092010-111323/.
Testo completoINTRODUCTION: Mitral valve repair is the treatment of choice to correct mixomatous mitral insufficiency. Tridimensional echocardiography studies demonstrate that mitral repair using prosthetic ring implant modifies mitral valve annulus morphology and function, although the literature related to mitral valve annulus behavior after mitral repair without use of prosthetic rings is scarce. OBJECTIVE: Analyze cardiac morphology and function using real time tridimensional echocardiography in individuals submitted to mitral valve repair with Double Teflon technique. CASUISTIC: Were included 14 patients with mitral valve insufficiency secondary to mixomatous degeneration that were submitted to mitral valve repair with the Double Teflon technique. Of them, 10 patients were male and the mean age was 61.3 ± 11.2 years. According to preoperatively functional class, 13 patients were in class III or IV. In preoperative echocardiographic analysis, the mean value of left ventricle end diastolic volume was 156.57 ± 46.61ml, and the left ventricle ejection fraction ranged between 38 and 68%, with average of 57.93 ± 6.67%. The mean value of the posterior annulus was 6.97 ± 0.13 cm. METHODS: Patients were evaluated in preoperative period, immediate postoperative period, 6 months and 1 year after mitral repair. Tridimensional echocardiography evaluated mitral annulus morphology by anterior and posterior measurements, transverse diameters and valve area. The annular function was evaluated through the ratio between internal valve areas during systole and diastole. Were evaluated left atrial and ventricle volumes and function. Statistic analysis was made by repeated measures ANOVA test and was considered statistically significant p < 0.05. RESULTS: Posterior mitral annulus demonstrated a significant reduction in immediate postoperative period (p<0.001), remaining stable during the study. There was no significant variation in valve area during the study. There was a significant reduction in anteroposterior and mediolateral diameters in the immediate postoperative period (p<0.001), although there was a significant increase in mediolateral diameter between immediate postoperative period and 1 year. Annular area variation over the cardiac cycle during the study ranged between 30.92 and 35.75%, without statistic significance. The analysis of systolic volumes, atrial and ventricular, demonstrated a significant volumetric reduction between immediate postoperative period and 1 year (p=0.028 and p=0.020, respectively). Between preoperative period and 1 year, there was a mean reduction in atrial and ventricle volumes of 19.9% and 15.4%, respectively. Atrial and ventricle diastolic volumes presented a significant reduction in immediate postoperative period (p<0.001 and p=0.024, respectively), remaining stable during the study. There was an increase in left atrial ejection fraction after 6 months (p<0.001), although there was no significant variation in left ventricle ejection fraction. CONCLUSIONS: Mitral valve repair with segmentar annuloplasty with the Double Teflon technique reduced the posterior mitral annulus, which remained stable in 1 year period. The variation in mitral annulus area during cardiac cycle remained stable during the study. Furthermore, there was a left atrial and ventricle reverse remodeling, associated with an improvement in left atrial function
Pinto, Nathali Cordeiro. "Análise do efeito do laser de alta potência em valvas mitrais cardíacas de suínos: estudo experimental". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5156/tde-22092014-161028/.
Testo completoIntroduction and Objective: In Brazil, valvar procedures represent at least 30% of cardiac surgeries performed in the country. It still predominate valvar lesions resulting from rheumatic fever and degenerative diseases. In rheumatic patients, the mitral valve is the most affected, predominantly stenosis due to commissural fusion and lesions in the subvalvar plane, however, thickening and retraction of the leaflets are also common, causing double lesion or mitral insufficiency. In degenerative process, the chordae tendineae may present elongated. In an attempt to further use of the laser as an auxiliary method in the surgical correction of valvar heart disease, we started experimental study with the purpose of comparing the histological swine tissue mitral valve (chordae tendineae and cusps) with and without high-power laser (HPL) application. Methods: Normal porcine mitral valve chordae and cups were studied and divided randomly into the following 6 groups: G1- Laser in the chordae tendineae with time of 15s; G2- Laser in the chordae tendineae with time of 20s; G3- Laser in the chordae tendineae with time of 30s; G4- Control Group; G5- Cusp group cut with a scalpel blade; G6- Cusp group cut with laser. Chordae tendineae from G1, G2 e G3 received diode laser (=980 nm, P=3,0 W) and G6 diode laser with other parameters (=980 nm, P=9,0 W, T=12s). Termography and optical coherence tomography were included during the procedure. Part of the sample was preserved in formaldehyde and glutaraldehyde for microscopic analysis and another part was stored in 0.9% saline for mechanical analysis. Results: There was a significant decrease in chordae length after laser application when compared to the initial length (p=0,005 to G1 and G2; p=0,004 to G3). In laser groups, histological analysis revealed a typical hyaline areas occupying almost the entire thickness of the chordae, when stained with Hematoxylin-Eosin (HE); dark red central areas when stained with Masson Trichrome and a birefringence decrease when stained with Picrocirius red. In mechanical analysis, we found lower stiffness, maximum rupture force decrease and larger displacement compared with the Control Group (p=0,005). In G5, was evidenced absence of any histological abnormality and a homogeneous blue appearance, typical of the cusp. However in G6, a basophilic hyaline aspect was found focally when stained with HE, dark red areas when stained with Masson Trichrome and a birefringence decrease when stained with Picrocirius Red. Conclusion: Chordae tendineae of normal porcine submitted to a high-power laser presented with reduced length, birefringence decrease and the collagen bundles organized into different orientations. Besides, presented lower stiffness, maximum rupture force decrease and larger displacement compared with the control group. Regarding cups, thermal changes were bigger in the cusp group cut with laser compared cusp group cut with scalpel blade, observed by optical microscopy
Grimes, Randall Young. "A theoretical and experimental analysis of mitral regurgitation and its interactions with pulmonary venous inflow". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/17246.
Testo completoRodrigues, Bruno Cristian. "Teste de estresse com Dobutamina em cães com Doença Degenerativa Valvar Mitral". Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154108.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A degeneração mixomatosa da válvula mitral (DMVM) é a enfermidade mais comum na clínica de pequenos animais no âmbito das cardiopatias, cuja evolução pode resultar em alterações hemodinâmicas importantes decorrentes dos mecanismos neuro-hormonais compensatórios. Embora seu diagnóstico seja relativamente simples, as alterações intrínsecas podem ser subestimadas pelos exames convencionais, a exemplo da disfunção sistólica e reserva miocárdica que podem passar despercebidas à ecocardiografia. Desta forma, o objetivo do presente estudo foi avaliar a ocorrência de disfunção sistólica em cães com DMVM por meio do teste de estresse farmacológico com dobutamina. Para tanto, foram utilizados três grupos de cães: G1 (n=8) grupo controle, G2 (n=7) animais com DMVM e diâmetro interno do ventrículo esquerdo em diástole indexado à aorta (DIVEd/Ao) < 2,37 e G3 (n=6) animais com DMVM e DIVEd/Ao ≥ 2,37 em um total de 21 animais. O ecocardiograma foi realizado antes (T0) e após (T1) infusão contínua com dobutamina, que foi realizada da seguinte forma: 5μg/kg/minuto por cinco minutos e 10μg/kg/minuto durante 10 minutos (T1). Os resultados foram avaliados pelo teste de Tukey com nível de significância de 5% quanto às variáveis fração de ejeção (FEJ%) (variação percentual média (VPM) de FEJ% antes e após a infusão de dobutamina), VPM de fração de encurtamento (FEC%) e diâmetros internos do ventrículo esquerdo em sístole e diástole indexados pelo diâmetro da aorta (DIVEs/Ao e DIVEd/Ao). Os resultados acerca da VPM FEC% e VPM FEJ%,demonstraram que houve diferença estatística quanto à primeira variável entre os grupos G1 com G3, bem como entre G2 e G3, enquanto em relação à segunda, apenas o G1 e G3 diferiram estatisticamente. Por outro lado não houve diferença significativa (p>0,05) para as médias obtidas pré e pós dobutamina da FEC% e FEJ% entre todos os grupos, no entanto, houve diferença significativa dentro os grupos G1 e G2 quando analisados os momentos T0 e T1. Outrossim, verificando as médias obtidas do DIVEd/Ao, conclui-se que houve diferença entre os grupos G1 e G3 como também entre G2 e G3 (p<0,05). Por sua vez, as médias obtidas do DIVEs/Ao diferiram significativamente (p<0,05) em todos os grupos pré (T0) e pós dobutamina (T1), exceto no G3. Entre os grupos, as médias no T0, têm diferença estatística significante entre os grupos G1 e G3 (p<0,05). Ademais, Em relação ao VVEs/m², dentro dos grupos houve diferença significativa apenas entre G1 e G3. Já entre os tempos, apenas o G1 houve diferença entre T0 e T1. Por fim, constatou-se significância estatística (p<0,05) quando se correlacionou DIVEd/Ao com a VPM FEC% e VPM FEJ%, demonstrando que quanto maior o DIVEd/Ao menores são estas variáveis. Desta forma, conclui-se que a dobutamina é capaz de evidenciar disfunção sistólica em animais com DMVM, principalmente naqueles que têm um remodelamento maior (G3), sendo capaz de inferir uma forte relação entre o tamanho do DIVEd/Ao e disfunção sistólica. Além disso, notou -se que em animais com menor remodelamento do ventrículo esquerdo (VE), como os do grupo G2, a resposta inotrópica ao desafio farmacológico foi satisfatória, revelando a presença de reserva contrátil nestes pacientes. Por fim, o teste de estresse com dobutamina mostrou-se eficaz, seguro e aplicável na rotina clínica.
Myxomatous mitral valve disease (MMVD) is the most common cardiopathy in small animals, which evolution may result in important hemodynamic changes due to compensatory neurohormonal mechanisms. Although its diagnosis is relatively simple, intrinsic changes may be underestimated by conventional exams, as systolic dysfunction and myocardial reserve that may go unnoticed by echocardiograph. Therefore, the objective of the present study was to evaluate the occurrence of systolic dysfunction in dogs with MMVD through pharmacological stress test with dobutamine. The dogs were distributed in three groups: G1 (n = 8) control group, G2 (n = 7) animals with MMVD and left ventricular diastolic diameter indexed to the aorta (LVIDd:Ao) < 2.37 and G3 (n = 6) animals with MMVD and LVIDd:Ao ≥ 2.37. The echocardiograph was performed before (T0) and after (T1) continuous infusion of dobutamine, as follows: 5μg/kg/minute for five minutes and 10μg/kg/minute for 10 minutes (T1). The results were evaluated by Tukey test with significance level of 5% for the following variables: ejection fraction (EF%) (mean percentage variation (MPV) of EF% before and after dobutamine infusion), MPV of shortening fraction FS% and internal diameters of left ventricle in systole and in diastole indexed by aortic diameter (LVIDs:Ao and LVIDd:Ao). The results about the MPV FS% and the MPV EF% showed that there was statistical difference between the G1 and G3 groups, as well as between G2 and G3, while the G1 and G3 differed statistically from the G1 and G3 groups. On the other hand, there was no significant difference (p> 0.05) for the averages obtained before and after dobutamine of the FS% and EF% among all groups, however, there was a significant difference between groups G1 and G2 when the T0 moments and T1. In addition, it was concluded that there were differences between the G1 and G3 groups as well as between G2 and G3 (p <0.05). Also, by means of the LVIDd:Ao means, it was concluded that there was a difference between the G1 and G3 groups as well as between G2 and G3 (p <0.05). In it’s turn, the means obtained from LVIDs:Ao differed significantly (p <0.05) in all groups before (T0) and post-dobutamine (T1), except in G3. Among the groups, the averages at T0, have significant statistical difference between the G1 and G3 groups (p <0.05). In addition, with respect to ESV/m², within the groups there was a significant difference only between G1 and G3. Among the times, only G1 showed differences between T0 and T1. Finally, statistical significance (p <0.05) was found when DIVEd / Ao correlated with MPV FS% and EF%, demonstrating that the higher the LVIDd:Ao the lower these variables. Therefore, it was determined that dobutamine can point to systolic dysfunction in animals with MMVD, especially those showing greater remodeling (G3), also inferring a strong relationship between LVIDd:Ao size and systolic dysfunction. Furthermore, in animals with less left ventricular (LV) remodeling, such as those in group G2, inotropic response to pharmacological challenge was satisfactory, revealing the presence of contractile reserve in these patients. To conclude, dobutamine stress test showed effective, safe and applicable in clinical routine.
Kozak, Marcelo Felipe. "Fatores associados à insuficiência moderada ou importante da valva atrioventricular esquerda no primeiro mês após correção de defeito de septo atrioventricular". Faculdade de Medicina de São José do Rio Preto, 2011. http://hdl.handle.net/tede/277.
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Introduction: One of the most often and important complications after surgical treatment of atrioventricular septal defects is the left atrioventricular valve insufficiency. So, this study was conducted to identify risk factors for moderate or severe left atrioventricular valve regurgitation within 30 days of surgical repair of atrioventricular septal defects at our center. Methods: This was a retrospective study in which we evaluated the results of 104 consecutive patients that were operated on at our practice between 2002 and 2010. The following associated factors were considered: age, weight, Down syndrome, grade of preoperative atrioventricular valve regurgitation, abnormalities on the atrioventricular valve and the use of annuloplasty. Patients were separated in two groups according to type of AVSD: group I (complete) and group II (incomplete – partial and transitional). Characteristics of the 53 patients of the group I: the median patient age at the time of repair was 6.7 months; the median weight was 5.3 Kg; 86.8% had Down syndrome; at the time of preoperative evaluation, there were 26 cases with moderate or severe atrioventricular valve regurgitation (49.1%); annuloplasty was perfored in 34%; abnormalities on the valve were found in 11.3% of the cases. Characteristics of the 51 patients of the group II: The median patient age at the time of repair was 4.1 years; the median weight was 13.4 Kg; 37.2% had Down syndrome; at the time of preoperative evaluation, there were 23 cases with moderate or grater LAVVR (45.1%); abnormalities on the AV valve were found in 17.6% of the cases; annuloplasty was performed in 21.6% of the patients. Results: Group I - At the time of post-operative evaluation, there were 21 cases with moderate or severe left atrioventricular valve regurgitation (39.6%). After performing a multivariate analysis, the only significant factor associated with these grades of insufficiency within 30 days of surgical correction of complete atrioventricular septal defect was the absence of Down syndrome (p = 0.03). Group II - At the time of postoperative evaluation, there were 12 cases with moderate or greater LAVVR (23.5%). During univariate analysis, only absence of Down syndrome was statistically significant (p = 0.02). However, after a multivariate analysis, none of the factors reached significance. Conclusion: Absence of Down syndrome proved to be associated with moderate or severe post-operative left atrioventricular valve regurgitation in patients with complete AVSD. However, none of the factors studied was determinant of a moderate or greater LAVVR within the first 30 days of repair of incomplete AVSD at our center.
Introdução: Uma das complicações mais frequentes e importantes do tratamento cirúrgico do defeito de septo atrioventricular (DSAV) é a insuficiência residual da valva atrioventricular esquerda, tanto nas formas totais, como parciais e transicionais. Dessa forma, esse estudo foi conduzido para identificar fatores de risco associados à insuficiência da valva atrioventricular esquerda (IVAVE) de grau moderado ou importante nos primeiros 30 dias após correção de defeito de DSAV. Métodos: Dados de 104 pacientes com DSAV operados entre 2002 e 2010 foram avaliados retrospectivamente, sendo estudados os seguintes fatores de risco: idade e peso no momento da correção, ausência de síndrome de Down, grau de insuficiência da valva atrioventricular (AV) antes da correção, anormalidades na valva AV e uso de anuloplastia. Os pacientes foram separados em dois grupos de acordo com o tipo de DSAV: grupo I (total) e grupo II (parcial e transicional). Características dos 53 pacientes do grupo I: a mediana da idade foi de 6,7 meses e a do peso de 5,3 Kg; 86,8% tinham síndrome de Down; antes da operação, 26 pacientes apresentavam insuficiência pelo menos moderada da valva AV (49.1%); anuloplastia foi realizada em 34% dos pacientes; anormalidades na valva AV foram encontradas em 11.3% dos casos. Características dos 51 pacientes do grupo II: a mediana da idade foi de 4,1 anos e a do peso de 13,4 Kg; 37,2% tinham síndrome de Down; antes da operação, 23 pacientes apresentavam IVAVE pelo menos moderada (45,1%); anormalidades na valva AV foram encontradas em 17,6% dos casos; anuloplastia foi realizada em 21,6% dos pacientes. Resultados: Grupo I – Após a correção cirúrgica, 21 casos apresentaram IVAVE pelo menos moderada (39,6%). Pela análise multivariada, o único fator associado com IVAVE pelo menos moderada no pós-operatório foi ausência de síndrome de Down (p = 0,03). Grupo II - Após a correção cirúrgica, 12 casos apresentaram IVAVE pelo menos moderada (23,5%). Pela análise univariada, apenas a ausência de síndrome de Down teve significância estatística (p = 0.02). Porém, após análise multivariada, nenhum dos fatores teve significância estatística. Conclusão: Ausência de síndrome de Down foi determinante de IVAVE moderada ou importante nos primeiros 30 dias após correção de DSAV total. Todavia, nenhum dos fatores estudados foi determinante para tais graus de IVAVE entre os pacientes com DSAV parcial e transicional.
Alleau, Thibaut. "Development of a numerical platform to model the mitral valve". Thesis, Compiègne, 2021. http://www.theses.fr/2021COMP2649.
Testo completoMitral insufficiency is the first valvular disease worldwide, with a 2% prevalence. When open-heartsurgery is impossible for the patient, surgeons use percutaneous devices to help the mitral leaflets coapt. However, the only device currently available is based on the edge-to-edge mitral valve repair technique. This type of implant is not adapted for patients suffering from functional mitral insufficiency, where the ventricle is responsible for the lack of coaptation of the leaflets. This thesis aims to provide a numerical platform to help the development of a mitral valve implant adapted for those patients. Several mitral valve geometries were created from a parametric model using anatomical measurements. Finite element simulations of the mitral valve were performed using ADINA to determine the valve closure under constant pressure. Several material models were developed in large strain and large deformation to model the valve closure accurately. Pathological behaviour such as annulus dilatation and chordae rupture were modelled, and several methods were tested to implement medical devices. Fluid-structure interaction of a 2D mitral valve was obtained using an ALE description and a monolithic coupling approach. Both the systole and the diastole were reproduced and studied, and the hermetic seal of the valve was detailed. The numerical platform developed is suited to model mitral valve function and can be used to help the development of mitral implants. In addition, the parametric geometry model and the anisotropic material model will be useful to depict with realism the valve function. A 3D fluid-structure interaction of the mitral valve could be developed
Patel, Leena Jayesh Gavin Timothy P. "Does minimally invasive robotic surgical treatment alter exercise tolerance in patients with atrial fibrillation and mitral regurgitation at seven to eleven weeks post-operative?" [Greenville, N.C.] : East Carolina University, 2009. http://hdl.handle.net/10342/1892.
Testo completoPresented to the faculty of the Department of Exercise and Sport Science. Advisor: Timothy P. Gavin. Title from PDF t.p. (viewed May 5, 2010). Includes bibliographical references.
Yap, Choon Hwai. "The fluid shear stress environment of the normal and congenital bicuspid aortic valve and the implications on valve calcification". Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45742.
Testo completoCosta, Cleinaldo de Almeida. "Evolução e complicações de ferimentos cardíacos: estudo de coorte prospectivo na cidade de Manaus". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5132/tde-04082008-104002/.
Testo completoObjectives: To evaluate the evolution and the complications of the patients that survived cardiac wounds, attended at the Pronto-Socorro Municipal 28 de Agosto and Hospital Pronto-Socorro Dr. João Lúcio Pereira Machado, in Manaus, during the period of January 1998 until June 2006. Methods: A medical records evaluation was made among the patients attended at the two emergency hospitals in which a cardiac wound was found during a exploring thoracotomy. The survivors that returned to the ambulatory were evaluated prospectively through electrocardiogram and echocardiogram, so it was possible to analyze the morphology and the function of the heart. A protocol was filled out with a registry of patients data, such as: age, sex, trauma mechanism, intra-operative and post-operative complications, and other variables. Results: The total reference population in this study was 100 patients, in which 95% were male, the majority (69%) had ages until 30; 81% of the lesions were caused by stab wounds; 78% of the orifice of entry were located at the precordium; 41% of the lesions wounded the right ventricle and 38% wounded the left ventricle; In 48% of the cases a left antero-lateral thoracotomy was executed. The survival rate was 72%. The studied population was of 25 patients that returned to the ambulatory and were prospectively evaluated with electrocardiogram and echocardiogram. Among the 33 echocardiogram alterations (ECO), seven patients (28%) had mitral insufficiency, while nine (36%) didn\'t have any alterations. Among the 45 electrocardiogram alterations (ECG), eight patients (32%) had sinusal tachicardia, while six (24%) had no alterations. Time made no difference in the results of the ECO (p=0,5323) or of the ECG (p=0,6596). Of the 14 detected ECO complications, three (21,4%) were due to IV degree lesions in the right ventricle and eleven (78,7%) were due to V degree lesions (in the left ventricle) (p=0,048). From the 12 left ventricle lesions that complicated (ECG), 9 were V degree. From the 12 alterations detected at the ECG, three (25%) were due to IV degree lesions and nine (75%) were due to V degree lesions (p=0,226). Conclusions: Approximately one third of the cardiac wound survivors did not have alterations in the electrocardiogram and echocardiogram. Left ventricle and V degree lesions from the OIS-AAST were related to a larger number of alterations in the electrocardiogram and echocardiogram. Sinusal Tachicardia and mitral insuficiency were alterations found in one third of the patients that survived a cardiac wound.
Müller, Regina Elizabeth. "Cardiopatia reumática com lesão valvar em crianças e adolescentes: fatores associados ao tempo até a terapêutica cirúrgica". Instituto Nacional de Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira, 2011. https://www.arca.fiocruz.br/handle/icict/8042.
Testo completoFundação Oswaldo Cruz. Instituto Nacional de Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira. Rio de Janeiro, RJ, Brasil.
Introdução: A cardiopatia reumática persiste como a principal doença cardiovascular adquirida em crianças e adultos jovens em todo o mundo, sendo responsável por altas taxas de morbimortalidade e evoluindo com frequência para a necessidade de cirurgia cardíaca valvar em pacientes na fase aguda ou crônica da doença. Objetivo: Estimar os fatores associados e o tempo desde o diagnóstico até a cirurgia cardíaca valvar em crianças e adolescentes portadores de cardiopatia reumática, em um centro cardiológico de referência terciária no Rio de Janeiro. Material e Métodos: estudo observacional longitudinal de base hospitalar, utilizando metodologia de análise de sobrevivência, para estimativa do tempo até a cirurgia, e modelo de regressão de Cox, para avaliar as razões de risco associadas segundo as covariáveis. A coorte foi composta por pacientes com 3 a 20 anos, cadastrados no Instituto Nacional de Cardiologia no Rio de Janeiro entre julho de 1986 e junho de 2006 e acompanhados até setembro de 2011. O diagnóstico da lesão valvar foi confirmado pelo exame Doppler-ecocardiográfico. As covariáveis, avaliadas no início do acompanhamento, foram reunidas em três dimensões: sociodemográfica (sexo, grupo etário, cor da pele, região de moradia e década do diagnóstico); clínica (apresentação clínica, classe funcional, número de surtos anteriores, profilaxia secundária, endocardite infecciosa e fibrilação atrial); e ecocardiográfica (lesão valvar por tipo e gravidade; diâmetro do átrio esquerdo, diâmetro sistólico do ventrículo esquerdo, função ventricular esquerda, hipertensão arterial pulmonar, e ruptura de cordoalha mitral). O banco de dados foi elaborado com o programa ACCESS 2000 e a análise estatística foi realizada pelo programa R versão 2.13.1. Foi considerado significativo o valor de - 0,05. Resultados: a coorte foi composta por 348 pacientes, 58% do sexo feminino, com idade mediana ao cadastro de 12,5 anos, e de 21,5 anos ao final do acompanhamento. O tempo médio de seguimento foi de 9,0 anos (2-21 anos). O evento cirurgia cardíaca ocorreu em 39% da amostra, com tempo mediano até a cirurgia de 22,3 anos. Na análise univariada todas as covariáveis das três dimensões (socioedemográfica, clínica e ecocardiográfica) apresentaram significância estatística e risco para realização de cirurgia cardíaca (hazard ratio>1), com exceção apenas da covariável região de moradia (p>0,5). Na análise multivariada, o modelo final incluiu as variáveis: década do diagnóstico, classe funcional, número de surtos anteriores, endocardite infecciosa, lesão valvar por tipo e gravidade, diâmetro do átrio esquerdo, diâmetro sistólico do ventrículo esquerdo e ruptura de cordoalha mitral. Conclusões: A realização da cirurgia cardíaca em pacientes com cardiopatia reumática está associada a fatores sociodemográficos, clínicos e ecocardiográficos.
Introduction: Rheumatic heart disease remains as the most common acquired heart disease in children and young adults all over the world, being responsible for high mortality and morbidity rates and often demanding valve surgery in the acute or chronic phase of the disease. Objective: To estimate the time from diagnosis until valve operation and the associated factors in children and young adults with rheumatic heart disease followed up in a tertiary center for cardiovascular care in Rio de Janeiro. Methods – It is a longitudinal observational study of a hospital based population, using survival analysis methodology for time estimation and Cox regression model for hazard risk evaluation of associated variables. Cohort was composed by 3 to 20 years old patients, registered in the National Institute of Cardiology (Instituto Nacional de Cardiologia), in Rio de Janeiro, between July 1986 and June 2006, and followed up until September 2011. Valve disease diagnosis was confirmed through Doppler echocardiography examination. Variables were evaluated at the patient´s first visit and separated in three dimensions: socio demographic (gender, age group, skin color, residence region, decade of diagnosis); clinic (disease status at presentation, functional class, number of previous rheumatic episodes, secondary prophylaxis, infectious endocarditis, atrial fibrillation); echocardiographic (valve lesion and severity, left atrium diameter, systolic left ventricle diameter, left ventricle function, pulmonary hypertension, rupture of mitral chordae). The database wasbased on the program ACCESS 2000 and statistical analysis was performed using the R Program version 2.13.1. For statistical analysis was considered as significant values for value 0.05. Results – 348 patients were included in the cohort, 58% female. Median age at the register was 12.5 years, and 21.5 years at the end of follow up. Median follow-up time was 9.0 years (2 to 21 years). 39% underwent valve operation and the median time until surgery was 22.3 years. In the univariate analysis all the variables from the three dimensions (socio demographic, clinic and echocardiographic) presented statistical significance as hazard risk in predicting valve operation (hazard ratio>1), with only one exception, that was residence region (p>0.5). In the multivariate analysis the final model included the following variables: decade of diagnosis, functional class, number of anterior rheumatic episodes, infectious endocarditis, valve lesion and severity, left atrium diameter, systolic left ventricle diameter and rupture of mitral chordate. Conclusions: Valve surgery in patients with rheumatic heart disease is associated with socio demographic, clinic and echocardiographic factors.
Machado, Fabrício Lorenzini Aranha. "Avaliação das concentrações séricas de adiponectina e sua correlação com obesidade e endocardiose de valva mitral em cães". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-26032013-102524/.
Testo completoObesity is defined as excessive accumulation of body fat, derived from a chronic imbalance between food intake and energy expended. This imbalance is related factors such as lifestyle (diet and physical activity), neuroendocrine disorders, and hereditary factors (MARQUES-LOPES et al., 2004). Obesity is not only affecting humans, making it an important element of studies and research, including pets such as dogs and cats. The obesity is usually done by direct inspection. Dogs and cats must be easily palpable ribs with hourglass configuration when viewed from above. Inability to palpate the ribs and the presence of fat deposits easily palpable at the base of the tail, on the hips or in the inguinal area suggest obesity. Ideally body fat are around 15% to 20% clothing (LEWIS et al., 1987). Adipose tissue is known as a local energy storage and synthesis of several hormones, among them, there is adiponectin, a protein responsible for the correlation between obesity associated with atherosclerosis (ISHIOKA et al., 2006). Exclusively expressed in adipocytes, its plasmatic concentration decreased with increase in body fat (ISHIOKA et al., 2006). Several studies have also suggested that adiponectin has its effect as a molecule anti-atherogenic and anti-inflammatory, proving to be a protective factor for cardiovascular disease (OUCHI et al., 1999, OUCHI et al., 2000), although values of circulating adiponectin should be interpreted with caution. It is known that obesity in humans is associated with increased morbidity and mortality from cardiovascular disease (ATKINS, 1991; GRUNDY, SLAUGHTER, 2004; WOFFORD; HALL, 2004), so measurement of the polypeptide can help show whether patients obese and / or heart are exposed to a greater or lesser risk of developing cardiovascular events. Thus, considering that several studies of adiponectin in obese humans associated with cardiovascular disease are controversial, and few published reports in veterinary medicine, aimed to evaluate the serum adiponectin in dogs: normal, overweight, with chronic mitral valve disease and In obese patients with concomitant mitral valve insufficiency using laboratory techniques for radioimmunoassay (RIA) and enzyme linked immuno sorbent assay (ELISA), checking whether a correlation exists between low serum adiponectin in obesity and in patients with chronic mitral valve insufficiency. For this, we selected 53 breeds, sex and ages were divided into four study groups. We carried out clinical evaluation and complementary addition to the measurement of serum adiponectin. The group of obese dogs associated with chronic mitral valve regurgitation tended to decrease in mean circulating concentrations of adiponectin by radioimmunoassay, when compared to other study groups.
"Investigation into mechanisms of functional mitral regurgitation by advanced echocardiographic technologies--dyssynchrony and beyond". Thesis, 2010. http://library.cuhk.edu.hk/record=b6074819.
Testo completoDespite comparable ejection fraction, higher degree of functional MR was associated with further impairment in short-axis myocardial deformation (circumferential and radial), but not with long-axis myocardial deformation. The degree of LV basal rotation was also lower in the MR patient group. Furthermore, the decrease in myocardial deformation was associated with greater extent of LV remodeling.
In conclusion, LV global mechanical dyssynchrony play a role in determining the severity of functional MR in addition to mitral leaflet tenting in patients with LV systolic dysfunction. Functional MR is associated with further impairment of myocardial deformation, but with differential change in individual component of myocardial deformation. CRT reduces functional MR in both early- and late-systolic phases, by way of improvement in LV remodeling, LV dyssynchrony and mitral leaflet tenting. Meanwhile, the improvement of MR contributes to LV reverse remodeling after CRT. (Abstract shortened by UMI.)
The improvement of functional MR was an independent predictor of LV reverse remodeling after CRT. The extent of LV reverse remodeling (reduction of LV end-systolic volume) was greatest in patients with improvement of MR, followed by those with "mild or no" MR at baseline, and was least in those without improvement of MR. CRT reduced functional MR by reducing both its early- and late-systolic components in heart failure patients. The reductions in LV end-systolic volume and dyssynchrony were related to the improvement of early-systolic MR, while the improvement of late-systolic MR was attributable to the reductions in mitral leaflet tenting and LV dyssynchrony.
The main findings were as follows: LV global systolic dyssynchrony served as an independent predictor for the presence of significant functional MR in patients with LV systolic dysfunction. Although mitral valvular tenting area was the most powerful predictor, LV global systolic dyssynchrony added incremental value to mitral valve tenting area in predicting the presence of significant functional MR.
We performed echocardiography with TDI and 2DSTE in 147 patients of both ischemic and non-ischemic etiologies with LV systolic dysfunction (defined as LV ejection fraction <50%) and 45 normal controls. MR severity, displacement of papillary muscle, mitral annular dilation and dysfunction, mitral leaflet tenting, LV remodeling and function were assessed by 2D and Doppler echocardiography. LV mechanical dyssynchrony indices were derived from TDI velocity. Myocardial strain (i.e. amount of deformation) in longitudinal, circumferential and radial directions and torsion (opposite rotational movement between apex and base of the heart) were measured by 2DTSE.
Liang, Yujia.
"October 2009."
Adviser: Cheuk man Yu.
Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: .
Thesis (Ph.D)--Chinese University of Hong Kong, 2010.
Includes bibliographical references (leaves 169-193).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
Leung, Dominic Y. C. "Exercise and left ventricular function in chronic mitral valve insufficiency /". 2002. http://www.library.unsw.edu.au/~thesis/adt-NUN/public/adt-NUN20030502.133258/index.html.
Testo completoChiou, Yu-Fang, e 邱郁芳. "Evaluation of Left Ventricular Systolic Dyssynchrony and Heterogeneity by Speckle Tracking Echocardiography in Dogs with Mitral Valve Insufficiency". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/60331581056201077847.
Testo completo國立中興大學
獸醫學系暨研究所
100
Left ventricular dyssynchrony (LVD) is observed in numbers of congestive heart failure patients. Because of the difference in systolic timing, LVD may further decrease cardiac output which will enhance the severity of the clinical signs, and increase mortality. The causes of LVD include myocardial dyssynergy and electrical activation delay, only the latter could be treated effectively by cardiac resynchronization therapy (CRT). Therefore, both of dyssynchrony and dyssynergy should be taken into consideration for distinguishing the cause of LVD. Dyssynergy is typical in ischemic heart disease with scar formation and endocardium dysfunction, which could make the transmural strain gradient (TSG) decrease. Thus, considering about TSG might also constructive to recognize the impact on myocardium. Mitral valve insufficiency is a common senile disease in small dogs. The increase regurgitant flow would make left ventricle remodeling and increase wall stress, this will compromise coronary perfusion. The aim of this study is using speckle tracking (STE) to evaluate the impact on dyssynchrony between different stages in mitral valve regurgitation (MR) Maltese dogs. Twenty healthy control group and thirty-three dogs with MR are classified according to the American College of Veterinary Internal Medicine (ACVIM) to MR1(n = 15), MR2(n =10) and MR3(n = 8). All dogs underwent conventional echocardiography and STE. The results demonstrated strain, DI, DNI and TSG might be influenced by MR. MR1 and MR2 are the most dyssynchrony and lowest TSG groups, MR3 is the most dyssynergy groups. These STE indices may be influenced by strain, myocardium remodeling and compensation. Consequently, although MR cause difference between groups and severity of dyssynergy is worst in MR3 as we expected, these STE indices should be more estimated for clinical application.
Кінаш, Роман Володимирович, e Roman Kinash. "Метод обробки фонокардіосигналу для виявлення мітральної недостатності клапанів серця людини". Master's thesis, 2019. http://elartu.tntu.edu.ua/handle/lib/29647.
Testo completoКінаш Роман Володимирович. Метод обробки фонокардіосигналу для виявлення мітральної недостатності клапанів серця людини. – Рукопис. Дипломна робота магістра за спеціальністю 163 «Біомедична інженерія», Тернопільський національний технічний університет імені Івана Пулюя, Тернопіль, 2019. Дипломну роботу магістра присвячено розробленні методу обробки фонокардіосигналу для виявлення мітральної недостатності клапанів серця людини. У роботі обґрунтовано математичну модель фонокардіосигналу у вигляді періодично корельованого випадкового процесу, яка має засоби та методи поєднання стохастичної природи та повторності сигналу, що є властивим для сигналів біологічного походження. На базі обґрунтованої математичної моделі у вигляді періодично корельованого випадкового процесу застосовано компонентний метод для обробки фонокардіосигналу, який дає змогу оперативно виявити мітральну недостатність клапанів серця людини. Розроблено програмне забезпечення в середовищі Matlab для автоматичних систем діагностики функціонального стану серцево-судинної системи на основі компонентного методу обробки фонокардіосигналу як періодично корельованої випадкової послідовності. Ключові слова: фонокардіосигнал, математична модель, періодично корельований випадковий процес, обробка, компонентний метод, виявлення мітральної недостатності клапанів серця людини, автоматизована система.
Kinash Roman. A method of phonocardiogram processing for a human heart valves mitral insufficiency detection. - Manuscript. Master's thesis on the specialty 163 "Biomedical Engineering", Ternopil Ivan Puliuj National Technical University, Ternopil, 2019. The master's thesis is devoted to the development of a method of processing the phonocardiosignal to detect the mitral insufficiency of the valves of the human heart. On the basis of a valid mathematical model in the form of a periodically correlated random process, a component method for the processing of phonocardiosignal is applied, which allows to expeditiously detect the mitral insufficiency of the valves of the human heart. The software in Matlab environment for automatic systems of diagnostics of the functional state of the cardiovascular system is developed based on the component method of processing the phonocardiosignal as a periodically correlated random sequence. Keywords: phonocardiosignal, mathematical model, periodically correlated random process, processing, component method, detection of mitral insufficiency of human heart valves, automated system.
ЗМІСТ ПЕРЕЛІК УМОВНИХ ПОЗНАЧЕНЬ 9 ВСТУП 10 РОЗДІЛ 1 ОГЛЯД СТАНУ ПРОБЛЕМИ ЗА НАПРЯМОМ НАУКОВОГО ДОСЛІДЖЕННЯ 13 1.1 Мітральна недостатність 13 1.2 Методи діагностики мітральної недостатності клапанів серця людини 14 1.2.1. Фізикальний 14 1.2.2 Аускультація 15 1.2.3. Фонокардіографія 16 1.3 Відомі математичні моделі фонокардіосигналів 21 1.3.1 Детерміновані моделі 21 1.3.2 Стохастичні моделі 21 1.4 Висновки до розділу 1 23 РОЗДІЛ 2. МАТЕМАТИЧНА МОДЕЛЬ ФОНОКАРДІОСИГНАЛУ 25 2.1 Параметри фонокардіосигналу 25 2.2 Обробка характеристик фонокардіосигналу 28 2.3 Енергетична теорія при моделюванні фонокардіосигналу 32 2.4 Математична модель фонокардіосигналу при недостатності мітральних клапанів 34 2.5 Висновки до розділу 2 38 РОЗДІЛ 3. МЕТОД ОБРОБКИ ФОНОКАРДІОСИГНАЛІВ 39 3.1 Реєстрація фонокардіосигналів 39 3.2 Методи обробки при недостатності мітральній 44 3.2.1 Когерентний метод обробки 47 3.2.2 Компонентний метод обробки 49 3.3 Алгоритм методу компонентної обробки фонокардіосигналів при виявленні мітральної недостатності клапанів серця людини 51 3.4 Висновки до розділу 3 53 7 РОЗДІЛ 4. РЕЗУЛЬТАТИ ОБРОБКИ ФОНОКАРДІОСИГНАЛУ 55 4.1 Блок-схема програмного забезпечення компонентної обробки фонокардіосигналу 55 4.2 Програмна реалізація компонентного методу аналізу 56 4.3 Блок схема програми для автоматичної обробки фонокардіосигналів 59 4.4 Реалізація програмного забезпечення автоматичної обробки фонокардіосигналів 60 4.5 Результати виявлення мітральної недостатності 66 4.6 Висновки до розділу 4 73 РОЗДІЛ 5. СПЕЦІАЛЬНА ЧАСТИНА 74 5.1 Метрологічне забезпечення медико-біологічних досліджень 74 5.2 Обґрунтування вибору УДК напряму наукового дослідження 77 5.3 Висновки до розділу 5 78 РОЗДІЛ 6. ОБГРУНТУВАННЯ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ 79 6.1 Розрахунок витрат на проведення науково-дослідної роботи 79 6.2 Науково-технічна ефективність науково-дослідної роботи 84 6.3 Висновки до розділу 6 88 РОЗДІЛ 7. ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 89 7.1 Охорона праці 89 7.2 Безпека в надзвичайних ситуаціях 91 7.3 Висновки до розділу 7 93 РОЗДІЛ 8. ЕКОЛОГІЯ 94 8.1 Cтатистична оцінка екологічного стану навколишнього природного середовища та закономірностей його розподілу 94 8.2 Моніторинг поверхневих вод 97 8.3 Висновки до розділу 8 100 ВИСНОВКИ 101 СПИСОК ВИКОРИСТАНИХ ДЖЕРЕЛ 102 ДОДАТКИ 106 8 ДОДАТОК А. Програмна реалізація компонентного методу обробки фонокардіосигналу 107 ДОДАТОК Б. Програмна реалізація графічного інтерфейсу програмного забезпечення обробки фонокардіосигналу 108 ДОДАТОК Д. Копія тези конференції 115