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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.
1

Tricuspid valve mechanics: understanding the effect of annular dilatation and papillary muscle displacement

Spinner, Erin M. 28 July 2011 (has links)
Tricuspid regurgitation (TR), back flow of blood from the right ventricle to the right atrium, has been reported in approximately 85% of the population, with 16% having mild or severe TR. Patients with untreated moderate to severe TR are likely to experience decreased exercise capacity and have increased morbidity and mortality, thus affecting the patient's quality of life. Current methods of repair offer limited rates of success, and many patients require further operations to correct returning levels of TR. Incomplete repair may be due to incomplete understanding of the functional anatomy and mechanics of the TV and the underlying causes of TR. It was hypothesized that alterations in the geometry of tricuspid valve annular and subvalvular apparatus induced by ventricular dilatation determine the severity of TR. In vivo measurements of papillary muscle (PM) position in patients with single or biventricular dilatation revealed PM displacement away from the center of the annulus as compared to control patients. Additionally, pulmonary arterial pressure, annulus area, ventricular size and apical displacement of the anterior PM were highly correlated with the severity of TR. An in vitro right-heart simulator was developed to investigate isolated mechanics of TR. Through these in vitro studies it was demonstrated that the tricuspid valve begins to leak at only 40% dilation, much lower than the mitral valve. Additionally, it was shown that isolated PM displacement resulted in significant TR. The highest levels of TR were achieved with a combination of annular dilatation and PM displacement. Alterations in leaflet coaptation, as quantified by measuring the amount of leaflet available for coaptation and leaflet mobility were observed with annular dilatation and PM displacement, both isolated and combined. The changes in leaflet coaptation resulted in redistribution of the forces on the chords originating from the anterior PM and inserting into the anterior and posterior leaflets. The findings herein provide the clinical and scientific community with a mechanistic understanding of the tricuspid valve to further improve intervention and repair of TV disease.
2

Nova técnica cirúrgica para a correção da anomalia de Ebstein: resultados imediatos e em longo prazo / New surgical technique for Ebsteins anomaly repair: early and long term results

Silva, José Pedro da 12 February 2008 (has links)
Introdução: As principais operações para correção da anomalia de Ebstein baseiam-se na reconstrução da valva atrioventricular direita (AVD) em formato monovalvular, tendo resultados comprometidos pela necessidade de substituição ou alta reincidência de insuficiência valvar. Uma nova técnica foi desenvolvida, diferenciado-se das anteriores, pela correção anatômica da valva AVD, resultando na coaptação plena das válvulas no fechamento valvar. O objetivo deste estudo é avaliar a aplicabilidade dessa técnica, estudando os seus efeitos na evolução clínica, função da valva, restauração do ventrículo direito funcional e remodelamento reverso do coração no pós-operatório imediato (POI) e no pós-operatório em longo prazo (POL). Métodos: Estudo retrospectivo de 52 pacientes consecutivos, com idade média de 18,5±13,8anos, submetidos técnica do cone para correção da anomalia de Ebstein, entre novembro 1993 e dezembro de 2006, cujos principais detalhes cirúrgicos são: as válvulas anterior e posterior da valva AV direita são mobilizadas das suas implantações anômalas no ventrículo direito (VD), a borda livre desse conjunto é rodada no sentido horário para ser suturada à, previamente mobilizada, borda septal da válvula anterior, formando um cone cujo vértice permanece fixo ao ápice do VD e a base é suturada no nível do anel atrioventricular verdadeiro, reduzido ao mesmo tamanho da base do cone. A válvula septal, sempre que possível, é incorporada à parede do cone. A porção atrializada do VD é reduzida por plicatura longitudinal. Os dados clínicos, ecocardiográficos e os índices cardiotorácicos, obtidos nos períodos pré-operatório (PREOP) e pós-operatório, foram analisados. Resultados: Houve dois óbitos hospitalares (3,8 %) e dois óbitos no seguimento em longo prazo A melhora clínica foi significante, sendo a distribuição dos pacientes em classes funcionais de insuficiência cardíaca (NYHA), IV = 4, III = 27, II = 11 e I = 5 no PREOP, modificada para IV = 0, III = 1, II = 2 e I = 44 no pós-operatório em longo prazo (POL) (p<0,0001), com seguimento médio de 57 meses. Quatro pacientes foram reoperados, sendo realizada nova plastia valvar. O índice cardiotorácico de 0,66±0,09 no PREOP diminuiu para 0,54±0,06 no POL (p<0,0001). Os ecocardiogramas mostraram redução dos graus de insuficiência da valva AV direita (p<0,001), sendo a distribuição dos pacientes no pré-operatório, grau 1 = 0, grau 2 = 1, grau 3 = 15, grau 4 = 24, modificada para grau 1 = 19, grau 2 = 17, grau 3 = 4, grau 4 = 0 no POI, com pequena alteração no POL (grau 1 = 11, grau 2 = 22, grau 3 = 7, grau 4 = 0). A cavidade funcional do VD foi restaurada pela operação, ocorrendo aumento da área do VD funcional indexada de 8,53± 7,02 cm2/m2 no PREOP para 21,01±6,87 cm2/m2 no POI (p<0,001), e ficando inalterada em 20,28±5,26 cm2/m2 no POL (p>0,05). Conclusões: Esta técnica foi aplicável com baixa mortalidade hospitalar e sem necessidade de substituição valvar. Houve melhora clínica pós-operatória e baixa incidência de reoperações em longo prazo. A correção da insuficiência valvar foi eficaz e duradoura na maioria dos pacientes. Houve restauração da área funcional do VD e remodelamento reverso do coração. / Background: The main operations for Ebsteins anomaly repair are conceived to reconstruct the tricuspid valve (TV) in a monocusp format, but their results are restricted either by the need for valve replacement or by high incidence of postoperative valve regurgitation. A new surgical technique was developed, that performs an anatomical reconstruction of the tricuspid valve, realizing a leaflet-to-leaflet coaptation at the TV closure. The objective of this study is to access the feasibility of this technique, evaluating its effects in clinical outcome, tricuspid valve function, right ventricle (RV) morphology and reverse remodeling of the heart.Methods: Retrospective study on 52 consecutive patients, mean age of 18,5+- 13,8 years, treated with a new surgical technique for Ebsteins anomaly repair (the cone technique), between November 1993 and December 2006, which principal details are: a) the anterior and posterior tricuspid valve leaflets re mobilizedfrom their anomalous attachments in the RV, the free edge of this complex is rotated clockwise to be sutured to the septal border of anterior leaflet, creatind a cone which vertex remains fixed at RV apex and whose base is the sutured to a true tricuspid annulus, plicated to match it to base of said cone. The septal leaflet is incorporated into the cone wall ewhenever possible. The atrialized chamber is reduced by longitudinal placation. The clinical and echocardiographic data and the patients cardiothoracic ratios, collected at the preoperative, early and late postoperative periods, were analyzed. Results: There were two hospital deaths (3.8 %) and two more deaths in the long term followup. The significant clinical improvement was evident by the change of patients functional class of heart failure (NYHA) from IV=4, III=27, II=11 and I=5, in the preoperative to IV =0, III = 1, II = 2 e I = 44 at 57 months mean long term follow-up (p<0,0001). Four patients required late TV re-repair. Atrioventricular block did not occur and there was no need for tricuspid valve replacement at any time. The cardiothoracic ratio decreased from 0,66+-0,09, preoperatively, to 0,54+-0,06 in long term follow-up (p<0,001). Echocardiographic studies showed significant TV insufficiency reduction from the preoperative patient distribution of: grade 1 = 0, grade 2 = 1, grade 3 = 15, grade 4 = 24, modified to: grade 1 = 19, grade 2 = 17, grade 3 = 4, grade 4 = 0 on early postoperative period (p<0.001), with little change afterwards (grade 1 = 11, grade 2 = 22, grade 3 = 7, grade 4 = 0). The normal RV morphology was surgically restored, indicated by the enlargement of RV indexed area from 8.53+-7.02 cm2/m2, preoperatively to 21.01+-6.87 cm2/m2 in the early perioperative period (p<0.001), remaining unchanged, 20.28+-5.26 cm2/m2 in long term echocardiogram (p>0,05). Conclusions: This operative technique was feasible with low hospital mortality and no need for TV replacement. There was improvement in the patients clinical status and low incidence of reoperations in long term follow-up. The TV repair was efficacious and durable for the great marjority of patients and there was immediate RV morphology restoration and reverse remodeling of heart in long term follow-up
3

Nova técnica cirúrgica para a correção da anomalia de Ebstein: resultados imediatos e em longo prazo / New surgical technique for Ebsteins anomaly repair: early and long term results

José Pedro da Silva 12 February 2008 (has links)
Introdução: As principais operações para correção da anomalia de Ebstein baseiam-se na reconstrução da valva atrioventricular direita (AVD) em formato monovalvular, tendo resultados comprometidos pela necessidade de substituição ou alta reincidência de insuficiência valvar. Uma nova técnica foi desenvolvida, diferenciado-se das anteriores, pela correção anatômica da valva AVD, resultando na coaptação plena das válvulas no fechamento valvar. O objetivo deste estudo é avaliar a aplicabilidade dessa técnica, estudando os seus efeitos na evolução clínica, função da valva, restauração do ventrículo direito funcional e remodelamento reverso do coração no pós-operatório imediato (POI) e no pós-operatório em longo prazo (POL). Métodos: Estudo retrospectivo de 52 pacientes consecutivos, com idade média de 18,5±13,8anos, submetidos técnica do cone para correção da anomalia de Ebstein, entre novembro 1993 e dezembro de 2006, cujos principais detalhes cirúrgicos são: as válvulas anterior e posterior da valva AV direita são mobilizadas das suas implantações anômalas no ventrículo direito (VD), a borda livre desse conjunto é rodada no sentido horário para ser suturada à, previamente mobilizada, borda septal da válvula anterior, formando um cone cujo vértice permanece fixo ao ápice do VD e a base é suturada no nível do anel atrioventricular verdadeiro, reduzido ao mesmo tamanho da base do cone. A válvula septal, sempre que possível, é incorporada à parede do cone. A porção atrializada do VD é reduzida por plicatura longitudinal. Os dados clínicos, ecocardiográficos e os índices cardiotorácicos, obtidos nos períodos pré-operatório (PREOP) e pós-operatório, foram analisados. Resultados: Houve dois óbitos hospitalares (3,8 %) e dois óbitos no seguimento em longo prazo A melhora clínica foi significante, sendo a distribuição dos pacientes em classes funcionais de insuficiência cardíaca (NYHA), IV = 4, III = 27, II = 11 e I = 5 no PREOP, modificada para IV = 0, III = 1, II = 2 e I = 44 no pós-operatório em longo prazo (POL) (p<0,0001), com seguimento médio de 57 meses. Quatro pacientes foram reoperados, sendo realizada nova plastia valvar. O índice cardiotorácico de 0,66±0,09 no PREOP diminuiu para 0,54±0,06 no POL (p<0,0001). Os ecocardiogramas mostraram redução dos graus de insuficiência da valva AV direita (p<0,001), sendo a distribuição dos pacientes no pré-operatório, grau 1 = 0, grau 2 = 1, grau 3 = 15, grau 4 = 24, modificada para grau 1 = 19, grau 2 = 17, grau 3 = 4, grau 4 = 0 no POI, com pequena alteração no POL (grau 1 = 11, grau 2 = 22, grau 3 = 7, grau 4 = 0). A cavidade funcional do VD foi restaurada pela operação, ocorrendo aumento da área do VD funcional indexada de 8,53± 7,02 cm2/m2 no PREOP para 21,01±6,87 cm2/m2 no POI (p<0,001), e ficando inalterada em 20,28±5,26 cm2/m2 no POL (p>0,05). Conclusões: Esta técnica foi aplicável com baixa mortalidade hospitalar e sem necessidade de substituição valvar. Houve melhora clínica pós-operatória e baixa incidência de reoperações em longo prazo. A correção da insuficiência valvar foi eficaz e duradoura na maioria dos pacientes. Houve restauração da área funcional do VD e remodelamento reverso do coração. / Background: The main operations for Ebsteins anomaly repair are conceived to reconstruct the tricuspid valve (TV) in a monocusp format, but their results are restricted either by the need for valve replacement or by high incidence of postoperative valve regurgitation. A new surgical technique was developed, that performs an anatomical reconstruction of the tricuspid valve, realizing a leaflet-to-leaflet coaptation at the TV closure. The objective of this study is to access the feasibility of this technique, evaluating its effects in clinical outcome, tricuspid valve function, right ventricle (RV) morphology and reverse remodeling of the heart.Methods: Retrospective study on 52 consecutive patients, mean age of 18,5+- 13,8 years, treated with a new surgical technique for Ebsteins anomaly repair (the cone technique), between November 1993 and December 2006, which principal details are: a) the anterior and posterior tricuspid valve leaflets re mobilizedfrom their anomalous attachments in the RV, the free edge of this complex is rotated clockwise to be sutured to the septal border of anterior leaflet, creatind a cone which vertex remains fixed at RV apex and whose base is the sutured to a true tricuspid annulus, plicated to match it to base of said cone. The septal leaflet is incorporated into the cone wall ewhenever possible. The atrialized chamber is reduced by longitudinal placation. The clinical and echocardiographic data and the patients cardiothoracic ratios, collected at the preoperative, early and late postoperative periods, were analyzed. Results: There were two hospital deaths (3.8 %) and two more deaths in the long term followup. The significant clinical improvement was evident by the change of patients functional class of heart failure (NYHA) from IV=4, III=27, II=11 and I=5, in the preoperative to IV =0, III = 1, II = 2 e I = 44 at 57 months mean long term follow-up (p<0,0001). Four patients required late TV re-repair. Atrioventricular block did not occur and there was no need for tricuspid valve replacement at any time. The cardiothoracic ratio decreased from 0,66+-0,09, preoperatively, to 0,54+-0,06 in long term follow-up (p<0,001). Echocardiographic studies showed significant TV insufficiency reduction from the preoperative patient distribution of: grade 1 = 0, grade 2 = 1, grade 3 = 15, grade 4 = 24, modified to: grade 1 = 19, grade 2 = 17, grade 3 = 4, grade 4 = 0 on early postoperative period (p<0.001), with little change afterwards (grade 1 = 11, grade 2 = 22, grade 3 = 7, grade 4 = 0). The normal RV morphology was surgically restored, indicated by the enlargement of RV indexed area from 8.53+-7.02 cm2/m2, preoperatively to 21.01+-6.87 cm2/m2 in the early perioperative period (p<0.001), remaining unchanged, 20.28+-5.26 cm2/m2 in long term echocardiogram (p>0,05). Conclusions: This operative technique was feasible with low hospital mortality and no need for TV replacement. There was improvement in the patients clinical status and low incidence of reoperations in long term follow-up. The TV repair was efficacious and durable for the great marjority of patients and there was immediate RV morphology restoration and reverse remodeling of heart in long term follow-up
4

Disparities in Survival and Mortality among Infants with Congenital Aortic, Pulmonary, and Tricuspid Valve Defects by Maternal Race/Ethnicity and Infant Sex

Conklin, Colleen 01 January 2011 (has links)
Background: The etiology of congenital heart valve defects is not well understood; little is known about the risk factors that contribute to the survival and mortality outcomes of children with these defects. Methods: Using data from the Texas Birth Defects Registry (TBDR) we conducted a retrospective cohort study of 2070 singleton infants with congenital aortic, pulmonary, or tricuspid valve atresia or stenosis born in Texas between January 1, 1996 and December 31, 2007 to Hispanic, Non-Hispanic (NH) black, and NH white women. TBDR data were death-to-birth matched by the Texas Vital Statistics Unit for deaths between January 1, 1996 and December 31, 2008. Using Kaplan-Meier survival estimates with log rank tests and Cox proportional hazards regression model hazard ratios (HR) with 95% confidence intervals (CI), we examined whether infant sex and maternal race/ethnicity affected early childhood survival or risk of mortality for children with congenital heart valve defects. Covariates included birth weight and gestational age, maternal age, maternal education, and number of co-occurring birth defects. Results: In children with aortic valve atresia and aortic valve stenosis, we found males had higher early childhood survival than females (55.0% vs. 41.5%, P=0.0451 and 91.6% vs. 82.5%, P=0.0492, respectively). Early childhood survival for males (94.9%) with pulmonary valve stenosis was slightly lower than females (97.1%, P=0.0116), and was also lower for NH black (94.1%) and Hispanic (95.3%) children than NH white children (97.8%, P=0.0340). After adjusting for covariates, early childhood mortality in children with pulmonary valve atresia with hypoplastic right ventricle was greater in NH black than NH white children (HR=2.93, CI 1.09-7.85, P=0.0329) and greater in NH black males than NH white males (HR=4.63, CI 1.12-19.19, P=0.0349). For children with tricuspid valve atresia, early childhood survival was lower in NH black males (35.7%) and Hispanic males (64.0%) than NH white males (81.0%, P=0.0269); after adjusting for covariates, risk for early childhood mortality was higher in NH black than NH white children (HR=3.39, CI 1.41-8.13, P=0.0062), and higher in NH black males than NH white males (HR=5.23, CI 133-20.58, P=0.0179). Conclusions: Our findings demonstrate there are disparities in early childhood survival and risk of mortality by infant sex and maternal race/ethnicity for children with congenital heart valve defects. These findings provide a foundation for further investigation to better understand why these disparities exist and what can be done to improve the outcomes for children with these defects.
5

Reversibility of severe mitral valve regurgitation after left ventricular assist device implantation single-centre observations from a real-life population of patients

Dobrovie, Monica 09 June 2020 (has links)
This study evaluates the impact of untreated preoperative severe mitral valve regurgitation (MR) on outcomes after left ventricular assist device (LVAD) implantation. Of the 234 patients who received LVAD therapy in the Heart Center Leipzig during a 6-year period, we selected those who had echocardiographic images of good quality and excluded those who underwent mitral valve replacement prior to or mitral valve repair during LVAD placement. The 128 patients selected were divided into 2 groups: Group A with severe MR (n = 65) and Group B with none to moderate MR (n = 63, 28 with moderate MR). We evaluated transthoracic echocardiography preoperatively [15 (7–28) days before LVAD implantation; median (interquartile range)] and postoperatively up to the last available follow-up [501 (283–848) days after LVAD]. We collected mortality, complications and clinical status indicators of the patient cohort. We observed a significant decrease in the severity of MR after LVAD implantation (severe MR 51% pre- vs 6% post-LVAD implantation, P < 0.001). There was no difference between groups in terms of right heart failure, rate of urgent heart transplantation, pump thrombosis or ventricular arrhythmias. There was no difference in 1-year survival and 3-year survival (87.7% vs 88.4% and 71.8% vs 66.6% for Groups A and B, respectively, P = 0.97). We concluded that preoperative severe MR resolves in the majority of patients early on after LVAD implantation and is not associated with worse clinical outcomes or intermediate-term survival.:Inhaltsverzeichnis Abkürzungsverzeichnis 3 1. Einführung 4 2. Formatierte Publikation 12 3. Zusammenfassung der Arbeit 19 4. Literaturverzeichnis 23 5. Anlagen 28 5.1. Statistical analysis of echocardiographic parameters in follow-up 28 5.2. Statistical Models Used 30 Darstellung des eignen wissenschaftlichen Beitrages 32 Erklärung über die eigenständige Abfassung der Arbeit 33 Lebenslauf 34 Publikationen 37 Danksagung 38
6

Cardiac output states in patients with severe functional tricuspid regurgitation: impact on treatment success and prognosis

Unterhuber, Matthias, Kresoja, Karl-Patrik, Besler, Christian, Rommel, Karl-Philipp, Orban, Mathias, von Roeder, Maximilian, Braun, Daniel, Stolz, Lukas, Massberg, Steffen, Trebicka, Jonel, Zachäus, Markus, Hausleiter, Jörg, Thiele, Holger, Lurz, Philipp 05 June 2023 (has links)
Aims To investigate whether there is evidence for distinct cardiac output (CO) based phenotypes in patients with chronic right heart failure associated with severe tricuspid regurgitation (TR) and to characterize their impact on TR treatment and outcome. Methods and results A total of 132 patients underwent isolated transcatheter tricuspid valve repair (TTVR) for functional TR at two centres. Patients were clustered according to k-means clustering into low [cardiac index (CI) < 1.7 L/min/m2], intermediate (CI 1.7–2.6 L/min/m2) and high CO (CI > 2.6 L/min/m2) clusters. All-cause mortality and clinical characteristics during follow-up were compared among different CO clusters. Mortality rates were highest for patients in a low (24%) and high CO state (42%, log-rank P < 0.001). High CO state patients were characterized by larger inferior vena cava diameters (P = 0.003), reduced liver function, higher incidence of ascites (P = 0.006) and markedly reduced systemic vascular resistance (P < 0.001) as compared to TTVR patients in other CO states. Despite comparable procedural success rates, the extent of changes in right atrial pressures (P = 0.01) and right ventricular dimensions (P < 0.001) per decrease in regurgitant volume following TTVR was less pronounced in high CO state patients as compared to other CO states. Successful TTVR was associated with the smallest prognostic benefit among low and high CO state patients. Conclusions Patients with chronic right heart failure and severe TR display distinct CO states. The high CO state is characterized by advanced congestive hepatopathy, a substantial decrease in peripheral vascular tone, a lack of response of central venous pressures to TR reduction, and worse prognosis. These data are relevant to the pathophysiological understanding and management of this important clinical syndrome. Graphical Abstract Proposed mechanism of hypercirculatory tricuspid regurgitation. Tricuspid regurgitation related backward failure causes liver congestion and dysfunction with portal hypertension and reduced washout of vasoactive substances. Consequent splanchnic and peripheral vasodilatation alongside with reduced renal blood flow results in renin–angiotensin–aldosterone system (RAAS) activation and sympathetic overactivation. The sympathetic drive and volume retention lead to further capacitance depletion and volume overload, eventually resulting in a high cardiac output state, with limited preload reduction and prognostic benefit following transcatheter tricuspid valve repair. The alterations in the graph should be interpreted as simultaneous interaction rather than a timeline. Continuous lines indicate findings in the present study. Dashed lines express currently accepted mechanistical considerations. AP, alkaline phosphatase; γGT, gamma-glutamyl-transferase; RA, right atrium; RV, right ventricle.
7

Determinação da proporção entre os segmentos do anel da valva tricuspide : estudo anatomico em corações de humanos / Proportion between the segments of the tricuspid valve annulus : anatomic study with human hearts

Antoniali, Fernando 26 July 2006 (has links)
Orientador: Domingo Marcolino Braile / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T03:55:43Z (GMT). No. of bitstreams: 1 Antoniali_Fernando_M.pdf: 4775200 bytes, checksum: 8361f227d501574e0c98c3965065c58b (MD5) Previous issue date: 2006 / Resumo: Objetivo: Determinar a proporção existente entre os segmentos do anel da valva tricúspide normal em humanos. Método: Foram estudados 30 corações de cadáveres humanos não formolizados, com menos de 6h de período ¿post-mortem¿, sem lesões congênitas ou adquiridas e com valvas tricúspides sem deformidades e continentes. A continência desta valva foi confirmada por injeção de água sob pressão no interior do ventrículo direito estando a valva pulmonar fechada. Foram realizadas fotos digitais da valva tricúspide com o anel valvar íntegro e após secção na comissura póstero-septal e retificação do anel valvar. Estas fotos contendo escalas milimetradas foram avaliadas por programa específico de computador. Foram feitas medidas computadorizadas do perímetro, segmento septal e segmento ântero-posterior do anel valvar íntegro. Nesta condição também foram feitas medidas da distância linear entre as comissuras ântero-septal e póstero-septal. Na condição de anel valvar retificado, foram realizadas medidas computadorizadas e manuais do perímetro e dos segmentos septal, anterior e posterior do anel valvar tricuspídeo. Compararam-se as medidas médias e as razões entre elas nas condições de anel íntegro e retificado. Compararam-se, também, a forma computadorizada e manual de mensuração do anel. Resultados: Nas medidas computadorizadas realizadas com imagens digitais do anel valvar íntegro, os valores médios do perímetro, segmento septal e ântero-posterior foram 105mm (±12,7), 30,6mm (±3,7) e 74mm (±9,4), respectivamente. A distância linear média entre as comissuras ântero-septal e póstero-septal foi de 28,9mm (±3,4). Nas medidas computadorizadas realizadas com imagens digitais do anel valvar retificado, os valores médios foram 117,5mm (±13,3), 32mm (±3,7), 46,3mm (±8,3) e 39,1mm (±8,5), respectivamente para perímetro, segmento septal, anterior e posterior. A razão média entre o segmento ântero-posterior e o septal foi 2,43 (±0,212) e 2,67 (±0,304) respectivamente em anéis íntegros e retificados. Houve diferenças significantes entre as medidas do perímetro (p<0,0001), do segmento septal (p=0,003) e do segmento ântero-posterior (p<0,0001) quando realizadas em anéis íntegros e retificados. As razões entre segmento ântero-posterior e septal também apresentaram diferença significante (p=0,0005). As medidas manuais do anel valvar retificado apresentaram os valores médios de 118,5mm (±12,7), 32,6mm (±3,4), 46,6mm (±7,7) e 39,3mm (±7,9), respectivamente para perímetro, segmento septal, anterior e posterior. Não houve diferenças significantes entre medidas manuais e computadorizadas. Conclusões: A proporção existente entre os segmento septal e o segmento ântero-posterior, do anel da valva tricúspide normal em humanos, é igual a 1 : 2,43. A secção e retificação do anel tricuspídeo altera as medidas de seus segmentos e suas relações / Abstract: Objective: The purpose of this study was to determine the proportion among the segments of the human tricuspid valve annulus. Methods: Descriptive autopsy study of 30 human hearts, without fixation, with less than six hours of post-mortem period, without congenital or acquired lesions and without tricuspid regurgitation. The tricuspid valve insufficiency was excluded by infusion of pressured water in the right ventricle with closed pulmonary valve. Digital images of the tricuspid ring on anatomical position and on flattened state were analyzed by specific software. Computerized measurements of the perimeter, septal segment, anteroposterior segment and the linear distance between the anteroseptal and posteroseptal commissures were obtained on anatomical position. Computerized and manual measurements of the perimeter, septal, anterior and posterior segments were obtained on flattened state. The measurements were demonstrated and compared on the two different situations, anatomical position and flattened. The computerized measurements were compared with the manual ones. Results: The mean values of the perimeter, septal and anteroposterior segments of the tricuspid ring, obtained by computerized measurements on anatomical position were: 105mm (±12.7), 30.6mm (±3.7) e 74mm (±9.4), respectively. The mean linear distance between the anteroseptal and posteroseptal commissures was 28.9mm (±3.4). On the flattened state and by computerized measurements, the mean value of the perimeter was 117.5mm (±13.3) and of the septal, anterior e posterior segments were respectively: 32mm (±3.7), 46.3mm (±8.3) e 39.1mm (±8.5). The mean ratio between the antero-posterior and septal segments was 2.43 (±0.212) on the anatomical position and on flattened state was 2.67 (±0.304). Statistical differences were observed in the measurements of perimeter (p<0.0001), septal segment (p=0.003) e antero-posterior segment (p<0.0001) on the two situations. Statistical difference also occurred on the ratios between the antero-posterior and septal segments (p=0.0005). The mean values obtained by manual measurements of the tricuspid ring on flattened state were: 118.5mm (±12.7), 32.6mm (±3.4), 46.6mm (±7.7) e 39.3mm (±7.9), respectively for perimeter, septal, anterior and posterior segments. There weren¿t statistical differences on computerized and manual measurements. Conclusions: The proportion between the septal and antero-posterior segments of the normal human tricuspid valve is 1 : 2.43. The attitude of flatting the tricuspid ring to measure the segments, changes their values and the ratios between them / Mestrado / Cirurgia / Mestre em Cirurgia
8

Validation of mitral regurgitation reversibility in patients with HeartMate 3 implantation

Schreiber, Constantin Frank 02 February 2023 (has links)
The resolution of functional mitral valve regurgitation (MR) in patients awaiting left ventricular assist device (LVAD) implantation is discussed controversially. The present study analyzed MR and echocardiographic parameters of the third-generation LVAD HeartMate 3 (HM3) over 3 years. Of 135 LVAD patients (with severe MR, n = 33; with none, mild, or moderate MR, n = 102), data of transthoracic echocardiography were included preoperatively to LVAD implantation, up to 1 month postoperatively, and at 1, 2, and 3 years after LVAD implantation. Demographic data and clinical characteristics were collected. Severe MR was reduced immediately after LVAD implantation in all patients. The echocardiographic parameters left ventricular end-diastolic diameter (P < .001), right ventricular end-diastolic diameter (P < .001), tricuspid annular plane systolic excursion (P < .001), and estimated pulmonary artery pressure (P < .001) decreased after HM3 implantation independently from the grade of MR prior to implantation and remained low during the 2 years follow-up period. Following LVAD implantation, right heart failure, ventricular arrhythmias, ischemic stroke as well as pump thrombosis and bleeding events were comparable between the groups. The incidences of death and cardiac death did not differ between the patient groups. Furthermore, the Kaplan-Meier analysis showed that survival was comparable between the groups (P = .073). HM3 implantation decreases preoperative severe MR immediately after LVAD implantation. This effect is long-lasting in most patients and reinforces the LVAD implantation without MR surgery. The complication rates and survival were comparable between patients with and without severe MR.
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Dopplervelocimetria do fluxo normal da valva tricúspide fetal entre 11 e 13 semanas e 6 dias de gestação / Normal fetal tricuspid valve dopplervelocimetry at 11 to 13 weeks and 6 days

Ninno, Milena Almeida Prado 14 April 2010 (has links)
Objetivo: Determinar os valores dopplervelocimétricos normais do fluxo através da valva tricúspide em gestações únicas, entre 11 e 13 semanas e seis dias. Examinar a reprodutibilidade dos parâmetros avaliados e sua correlação com variáveis clínicas maternas e obstétricas. Métodos: Estudo prospectivo envolvendo 166 gestações únicas, com desfecho normal, examinadas entre 11 e 13 semanas e seis dias, no período de fevereiro de 2006 a agosto de 2008. Foram aferidas as velocidades máximas das ondas E e A, duração do ciclo cardíaco completo e sua fase diastólica e calculadas as relações onda E/onda A e diástole/ciclo. Os valores normais foram descritos pelas respectivas médias e desvio-padrão. Para análise da reprodutibilidade desses parâmetros foi calculado o coeficiente de correlação intra-classes em 12 casos examinados por dois examinadores. Regressão linear simples e multivariada foram empregadas para examinar a correlação dos parâmetros dopplervelocimétricos entre si e com a idade gestacional, a medida da translucência nucal e variáveis maternas. Resultados: Neste intervalo gestacional, os valores normais encontrados foram: onda E, 25 (± 4,6) cm/s; onda A, 42,9 (± 5,9) cm/s; relação E/A, 0,58 (± 0,07); ciclo cardíaco, 390 (± 21,1) ms; diástole, 147 (± 18) ms; relação diástole/ciclo, 0,38 (± 0,04). Entre as variáveis dopplervelocimétricas, foi observada correlação significativa entre o ciclo cardíaco e diástole (r=0,53; p<0,0001), diástole e onda A (r=-0,15; p=0,05), ondas E e A (r=0,77; p<0,0001), onda E e relação D/C (r=0,16; p=0,04), onda A e relação diástole/ciclo (r=-0,17; p=0,03). Todas as variáveis, exceto a velocidade da onda A, correlacionaram-se positivamente com a idade gestacional. Não foi observada correlação significativa das variáveis com a medida da translucência nucal, e, na comparação com as variáveis maternas, apenas a onda E e a idade materna apresentaram correlação significativa (r=-0,18, p=0,04). Os coeficientes de correlação intra-classes para a avaliação interobservador e intra-observador (examinadores um e dois) foram: onda E = 0,53 (0,53 e 0,64); onda A = 0,45 (0,46 e 0,49); ciclo cardíaco = 0,70 (0,79 e 0,84) e diástole = 0,63 (0,85 e 0,82). Conclusão: O presente estudo estabeleceu os valores normais dos parâmetros dopplervelocimétricos do fluxo através da valva tricúspide e demonstrou que tais parâmetros, com exceção da onda A, correlacionaram-se de forma positiva com a idade gestacional, e apresentaram reprodutibilidade boa/moderada. / Objective: To establish the measurements of normal tricuspid valve flow velocities at 11 to 13 weeks and 6 days to determine E-wave, A-wave, E/A ratio, cardiac cycle length, diastole length, diastole/cardiac cycle ratio, and their relationship with gestational age, nuchal translucency thickness, the characteristics of the study population, and to assess the reproducibility of flow measurements. Methods: Between February, 2006, and August, 2008, a total of 166 women with a singleton normal pregnancy between 11 and 13 + 6 weeks of gestation consented to participate in the study. Analysis of the waveforms consisted of calculation of peak velocity (cm/s) of the E-wave and A-wave, E-wave/A-wave ratio, cardiac cycle length (ms), diastole length (ms) and diastole/cardiac cycle ratio. To evaluate the intraobserver and interobserver agreement, a subgroup of 12 patients, chosen randomly, was examined twice by each examiner. For descriptive analysis of the results were calculated average and standard deviation. Simple and multivariate linear regression was used to establish the correlation between dopplervelocimetry among parameters and with gestational age, nuchal translucency thickness and the characteristics of the study population. Results: The average (± standard deviation) for transtricuspid flow-velocities waveforms parameters were: E-wave 25 (± 4.6) cm/s; A-wave 42.9 (± 5.9) cm/s; E/A ratio 0.58 (± 0.07); cardiac cycle length 390 (± 21.1) ms; diastole length 147 (± 18) ms; diastole/cardiac cycle length 0,38 (± 0.04). A statistically significant linear increase relative to gestational age was established for all parameters, except A-wave. Nuchal translucency thickness was not correlated with any parameter. A statistically significant negative regression coefficient was established for E-wave to maternal age (r=-0,18, p=0,04). A statistically significant relationship was established between: cardiac cycle length and diastole length (r=0.53; p<0.0001); diastole length and A-wave velocity (r=-0.15; p=0.05); E-wave and A-wave velocities (r=0.77; p<0.0001); E-wave velocity and D/C ratio (r=0.16; p=0.04); A-wave velocity and D/C ratio (r=-0.17; p=0.03). The intraclass correlation coeficients of interobserver and intraobsever evaluations (examiners 1 and 2) were: Ewave = 0.53 (0.53 and 0.64); A-wave = 0.45 (0.46 and 0.49); cardiac cycle = 0.70 (0.79 and 0.84) and diastole= 0.63 (0.85 and 0.82). Conclusions: These data determine normal parameters for tricuspid valve dopplervelocimetry and shows that these parameters, except A-wave, have positive correlation with gestational age, and good/moderate reproducibility.
10

Dopplervelocimetria do fluxo normal da valva tricúspide fetal entre 11 e 13 semanas e 6 dias de gestação / Normal fetal tricuspid valve dopplervelocimetry at 11 to 13 weeks and 6 days

Milena Almeida Prado Ninno 14 April 2010 (has links)
Objetivo: Determinar os valores dopplervelocimétricos normais do fluxo através da valva tricúspide em gestações únicas, entre 11 e 13 semanas e seis dias. Examinar a reprodutibilidade dos parâmetros avaliados e sua correlação com variáveis clínicas maternas e obstétricas. Métodos: Estudo prospectivo envolvendo 166 gestações únicas, com desfecho normal, examinadas entre 11 e 13 semanas e seis dias, no período de fevereiro de 2006 a agosto de 2008. Foram aferidas as velocidades máximas das ondas E e A, duração do ciclo cardíaco completo e sua fase diastólica e calculadas as relações onda E/onda A e diástole/ciclo. Os valores normais foram descritos pelas respectivas médias e desvio-padrão. Para análise da reprodutibilidade desses parâmetros foi calculado o coeficiente de correlação intra-classes em 12 casos examinados por dois examinadores. Regressão linear simples e multivariada foram empregadas para examinar a correlação dos parâmetros dopplervelocimétricos entre si e com a idade gestacional, a medida da translucência nucal e variáveis maternas. Resultados: Neste intervalo gestacional, os valores normais encontrados foram: onda E, 25 (± 4,6) cm/s; onda A, 42,9 (± 5,9) cm/s; relação E/A, 0,58 (± 0,07); ciclo cardíaco, 390 (± 21,1) ms; diástole, 147 (± 18) ms; relação diástole/ciclo, 0,38 (± 0,04). Entre as variáveis dopplervelocimétricas, foi observada correlação significativa entre o ciclo cardíaco e diástole (r=0,53; p<0,0001), diástole e onda A (r=-0,15; p=0,05), ondas E e A (r=0,77; p<0,0001), onda E e relação D/C (r=0,16; p=0,04), onda A e relação diástole/ciclo (r=-0,17; p=0,03). Todas as variáveis, exceto a velocidade da onda A, correlacionaram-se positivamente com a idade gestacional. Não foi observada correlação significativa das variáveis com a medida da translucência nucal, e, na comparação com as variáveis maternas, apenas a onda E e a idade materna apresentaram correlação significativa (r=-0,18, p=0,04). Os coeficientes de correlação intra-classes para a avaliação interobservador e intra-observador (examinadores um e dois) foram: onda E = 0,53 (0,53 e 0,64); onda A = 0,45 (0,46 e 0,49); ciclo cardíaco = 0,70 (0,79 e 0,84) e diástole = 0,63 (0,85 e 0,82). Conclusão: O presente estudo estabeleceu os valores normais dos parâmetros dopplervelocimétricos do fluxo através da valva tricúspide e demonstrou que tais parâmetros, com exceção da onda A, correlacionaram-se de forma positiva com a idade gestacional, e apresentaram reprodutibilidade boa/moderada. / Objective: To establish the measurements of normal tricuspid valve flow velocities at 11 to 13 weeks and 6 days to determine E-wave, A-wave, E/A ratio, cardiac cycle length, diastole length, diastole/cardiac cycle ratio, and their relationship with gestational age, nuchal translucency thickness, the characteristics of the study population, and to assess the reproducibility of flow measurements. Methods: Between February, 2006, and August, 2008, a total of 166 women with a singleton normal pregnancy between 11 and 13 + 6 weeks of gestation consented to participate in the study. Analysis of the waveforms consisted of calculation of peak velocity (cm/s) of the E-wave and A-wave, E-wave/A-wave ratio, cardiac cycle length (ms), diastole length (ms) and diastole/cardiac cycle ratio. To evaluate the intraobserver and interobserver agreement, a subgroup of 12 patients, chosen randomly, was examined twice by each examiner. For descriptive analysis of the results were calculated average and standard deviation. Simple and multivariate linear regression was used to establish the correlation between dopplervelocimetry among parameters and with gestational age, nuchal translucency thickness and the characteristics of the study population. Results: The average (± standard deviation) for transtricuspid flow-velocities waveforms parameters were: E-wave 25 (± 4.6) cm/s; A-wave 42.9 (± 5.9) cm/s; E/A ratio 0.58 (± 0.07); cardiac cycle length 390 (± 21.1) ms; diastole length 147 (± 18) ms; diastole/cardiac cycle length 0,38 (± 0.04). A statistically significant linear increase relative to gestational age was established for all parameters, except A-wave. Nuchal translucency thickness was not correlated with any parameter. A statistically significant negative regression coefficient was established for E-wave to maternal age (r=-0,18, p=0,04). A statistically significant relationship was established between: cardiac cycle length and diastole length (r=0.53; p<0.0001); diastole length and A-wave velocity (r=-0.15; p=0.05); E-wave and A-wave velocities (r=0.77; p<0.0001); E-wave velocity and D/C ratio (r=0.16; p=0.04); A-wave velocity and D/C ratio (r=-0.17; p=0.03). The intraclass correlation coeficients of interobserver and intraobsever evaluations (examiners 1 and 2) were: Ewave = 0.53 (0.53 and 0.64); A-wave = 0.45 (0.46 and 0.49); cardiac cycle = 0.70 (0.79 and 0.84) and diastole= 0.63 (0.85 and 0.82). Conclusions: These data determine normal parameters for tricuspid valve dopplervelocimetry and shows that these parameters, except A-wave, have positive correlation with gestational age, and good/moderate reproducibility.

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