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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Cognitive Deficits in Cardiac Rehabilitation: A Comparison of Post-Bypass and Post-Angioplasty Patients

Bui, Matthew January 2017 (has links)
Mild cognitive deficits that negatively impact self-management education-related outcomes may be present in a proportion of cardiac rehabilitation patients and the degree of impairment may vary by the type of coronary revascularization procedure. The purpose of this study was to compare cognitive function, as measured by the Montreal Cognitive Assessment (MoCA), between coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) patients, and to determine independent variables of MoCA score. In a cross-sectional study, 78 cardiac rehabilitation patients (CABG n = 38, PCI n = 40) completed the MoCA. Demographics were collected and disease burden was calculated using the age-adjusted Charlson Comorbidity Index (ACCI). Mild cognitive deficits (MoCA ≤26) were present in 55.3% CABG and 30.0% PCI patients. An independent Student’s t test showed that MoCA scores were significantly lower among CABG patients (mean = 24.5, SD = 3.3) compared to PCI patients (M = 26.7, SD = 2.7), t (76) = 3.15, p < 0.01. Descriptive analyses of cognitive domain scores indicated that deficits in short-term memory and language were present among CABG patients. Using a backward regression, coronary revascularization procedure (CABG vs. PCI) (p = 0.006) and disease burden (ACCI) (p = 0.015) remained significant, while heart failure diagnosis became non-significant and was removed from the model (F (2, 75) = 8.382, p < 0.001). The final model explained 16.1% of the total variance in MoCA score (adjusted R2 = 0.161). Results indicate that cognitive deficits were present in cardiac rehabilitation participants and associated with the type of coronary revascularization procedure, suggesting the need for formal cognitive screening and adaptation of education interventions in cardiac rehabilitation. A future prospective cohort study is required to establish temporality, and to measure education-related outcomes, such as health-related quality of life (HRQOL) and self-management. / Thesis / Master of Science (MSc) / Cardiac rehabilitation (CR) is a multifaceted program consisting of exercise and education that is essential to the care of post-coronary revascularization patients. While exercise has shown to improve health outcomes, education has demonstrated inconsistent effects. Since education has imposed cognitive demands, this discrepancy in outcomes may, in part, be due to cognitive deficits present in a proportion of program attendees: the degree of impairment may vary by type of coronary revascularization procedure prior to CR. This study compared cognitive function between two groups of coronary revascularization patients, post-coronary bypass surgery and post-coronary angioplasty, and determined independent variables for cognitive function. Results showed that coronary bypass surgery patients had significantly lower cognitive function than coronary angioplasty patients at program intake. Coronary bypass surgery and accumulated disease burden were weakly associated with decreased cognitive function. Cognitive screening and adapted education for patients with cognitive deficits should be considered to improve CR outcomes.
22

Estudo comparativo entre os custos dos tratamentos clínico, cirúrgico ou percutâneo em portadores de doença multiarterial coronária estável - 5 anos de seguimento / Comparative cost analysis for surgical, angioplasty, or medical therapeutics for coronary artery disease - 5-year follow-up

Vieira, Ricardo D'Oliveira 06 June 2013 (has links)
Estudo comparativo entre os custos dos tratamentos clínico, cirúrgico ou percutâneo em portadores de doença multiarterial coronária estável - 5 anos de seguimento [tese]. São Paulo: Faculdade de Medicina, Universidade de São Paulo, 2013. INTRODUÇÃO: As principais opções terapêuticas para a doença multiarterial coronária incluem cirurgia de revascularização miocárdica (CRM), intervenção coronária percutânea (ICP) e tratamento clínico (TC). Essas três estratégias terapêuticas apresentam eficácia similar em determinados subgrupos de pacientes. No presente momento, estudos direcionados à análise econômica são escassos, e contemplam, principalmente, os custos comparativos entre as intervenções cirúrgica e percutânea. OBJETIVOS: Analisar, prospectivamente, o custo comparativo das três formas terapêuticas da doença multiarterial coronária estável, durante cinco anos de seguimento. MÉTODOS: Foi computado o custo terapêutico global de 611 pacientes do ensaio clínico The Second Medicine, Angioplasty, or Surgery Study (MASS II), baseado na remuneração provida pelo sistema de saúde suplementar do Instituto do Coração do HC/FMUSP, tomando-se os valores em moeda nacional corrente. Realizou-se, posteriormente, análise de custo-efetividade para o tempo livre de eventos clínicos e o tempo livre de eventos acrescido de tempo livre de angina. RESULTADOS: O TC apresentou 3.79 e 2.07 QALY (quality-adjusted lifeyears); o ICP apresentou 3.59 e 2.77 QALY; e o CRM apresentou 4.4 e 2.81 QALY, respectivamente, para sobrevida livre de eventos e sobrevida livre de eventos e angina. Os custos para sobrevida livre de eventos foram R$ 16.327,80 para TC, R$ 35.940,60 para ICP e R$ 32.873,40 para CRM. A análise pareada dos custos para sobrevida livre de eventos mostrou que houve diferença significante favorecendo TC contra ICP (P < 0,01), e em comparação com CRM (P < 0,01); e CRM versus ICP (P = 0,01). Os custos para sobrevida livre de eventos e angina foram R$ 29.795,40, R$ 46.495,80 e R$ 44.305,20, respectivamente. A comparação pareada dos custos livres de eventos mais livres de angina demonstrou que houve diferença significante favorecendo TC contra ICP (P = 0,04), e em comparação com CRM (P < 0,001). Não houve diferença entre CRM e ICP (P > 0,05). CONCLUSÃO: A análise comparativa entre as diferentes opções terapêuticas desta amostra revelou que TC foi mais custo-efetivo que CRM, e esta, por sua vez, mais custo-efetivo que ICP / BACKGROUND: The therapeutic options for multivessel coronary artery disease are coronary artery bypass graft surgery (CABG), percutaneous coronary intervention (PCI), or medical treatment alone (MT). These three therapeutic strategies present similar efficacy for specific subgroups. At the present moment, economic outcome trials are scant, and contemplate comparative cost between surgical or percutaneous intervention. OBJECTIVE: To analyze, prospectively, the comparative cost from three therapeutic strategies in multivessel coronary artery disease, at 5-year of follow-up. METHODS: We analyzed cumulative costs of 611 patients from clinical trial The Second Medicine, Angioplasty, or Surgery Study (MASS II). The economic analysis is based on remuneration provided by the supplementary health system of the Heart Institute of the Clinical Hospital of FMUSP, expressing these values in Brazilian currency. It was compared to the cumulative costs of each therapeutic strategy in the 5-year follow-up period. A cost-effectiveness analysis was then conducted for event-free survival and event plus angina-free survival. Cost-effectiveness analysis was performed by quality-adjusted life- year (QALY) analysis. RESULTS: Respectively, for event-free survival and event plus angina-free survival, MT presented 3.79 quality-adjusted life-years (QALY) and 2.07 QALY; PCI presented 3.59 and 2.77 QALY; and CABG demonstrated 4.4 and 2.81 QALY. The event-free costs were R$ 16327.80 for MT; R$ 35940.60 for PCI; and R$ 32873.40 for CABG. The paired comparison of the event-free costs showed that there was a significant difference favoring MT versus PCI (P < 0.01) and versus CABG (P < 0.01) and CABG versus PCI (P =0.01). The event-free plus angina-free costs were R$ 29795.40, R$ 46495.80 e R$ 44305.20, respectively. The paired comparison of the event-free plus angina-free costs showed that there was a significant difference favoring MT versus PCI (P =0.04), and versus CABG (P < 0.001); there was no difference between CABG and PCI (P > 0.05). CONCLUSION: The comparative analysis among the different therapeutic strategies demonstrated that MT was more cost-effective than CABG, and this than PCI
23

Ventricular Long Axis Function: Amplitudes and Timings : Echocardiographic Studies in Health and Disease

Bukachi, Frederick January 2004 (has links)
Background: The ageing process not only increases the risk of coronary artery disease (CAD) but also complicates its diagnosis and treatment. It is therefore important to understand the newer concepts of cardiovascular ageing physiology as well as methods of predicting the outcomes of therapeutic options available for the elderly with severe CAD. Studies of atrioventricular (AV) ring or plane motion have attracted considerable interest in the last few years as a means of assessing ventricular and atrial function. As the displacement of AV rings towards the ventricular apex is a direct reflection of longitudinal fibre contraction, its measurement by echocardiography provides additional information regarding global and regional systolic and diastolic function. Left ventricular (LV) long axis amplitude of motion, referred to as mitral valve annular (MA) motion, is reduced in CAD and to some extent in the elderly as part of the normal ageing process. Objectives &amp; Methods: The aim of the present study was two-fold. First, to investigate the relationship between the timing of MA motion and transmitral and pulmonary venous flow in healthy subjects, and to define the physiological significance of that relationship including its potential diagnostic utility. Second, to investigate the relationship between the clinical outcome and the behaviour of long axis function in patients with severe ischaemic LV dysfunction (SLVD) after percutaneous coronary angioplasty (PTCA). Transmitral early (E) and late (A) filling, and pulmonary venous flow reversal (Ar) were studied by Doppler echocardiography, while at the left lateral AV ring, the MA motion in early (Em) and late (Am) diastole were recorded by Doppler tissue imaging (DTI) and M-mode echocardiography. Results: Healthy subjects – In early diastole the onsets of LV filling (E) and relaxation (Em) were simultaneous, and peak Em preceded peak E by 26 msec in all age groups, constituting a time interval referred to as early diastolic temporal discordance (EDTD). Similarly, the onsets of Am, A and Ar were simultaneous at onset and began approximately 84 msec after the electrocardiographic P wave. Peak Am preceded peak A by 23 msec in the young and by 13 msec in the elderly, a time interval referred to as late diastolic temporal discordance (LDTD). Peak Ar, on the other hand, coincided with peak Am in all age groups. With increasing age and sequential prolongation of isovolumic relaxation time, the peaks of Am, Ar and A converged. This point of convergence is described as atrial mechanical alignment (AMA). Patients – MA total amplitude of motion, rates of shortening and lengthening were all reduced in patients with SLVD. At mid-term, 3-6 months after PTCA, there was improvement in all these variables. A pre-procedure long axis cut off value of ≥5 mm was associated with favourable symptomatic outcome. Overall angiographic success was 95.2%, and event-free survival was 78.4% at one month and declined steadily to 62.3% at one year with 2.5% mortality. Conclusions: EDTD, which reflects ventricular restoring forces (suction) is age independent while the narrowing of LDTD leading to AMA provides a novel method to identify healthy subjects at increased dependency on left atrial contraction for late diastolic filling. Peak atrial contraction (Am) coincides with peak Ar, thus the timing of regional atrial contraction by DTI can be used to estimate corresponding measurements of Ar, which is often difficult to image by transthoracic echocardiography. In patients with SLVD long axis total amplitude of at least 5 mm at the left MA suggests a significant potential for segmental function recovery after PTCA. Keywords: Echocardiography, Doppler tissue imaging, ageing, coronary disease, left ventricular dysfunction, atrial contraction, electromechanical function, coronary angioplasty.
24

Specifika ošetřovatelské péče u klientů/pacientů s komplikacemi po selektivní koronarografii/PTCA / Specifications of nursering care of patiens with complications after direct SKG/PTCA

BLÁHOVÁ, Ilona January 2010 (has links)
Abstract In the Czech Republic there is no doubt about the tendency of gradual increase in median life expectancy, which is significantly affected by the fact that mortality from cardiovascular diseases, especially from acute coronary syndromes, has been decreasing. Besides the provable effect of a healthy lifestyle, diet and, by all means, a quality and effective pharmacotherapy, a significant development in the field of interventional cardiology contributes to this accomplishment. The number of coronographies, coronary angioplasties and implanted stents have multiplied, and today the invasive coronarographic diagnostics and percutaneous myocardial revascularization belong to the the most common diagnostic and therapeutic methods in treatment of acute forms of ischemic heart diseases. An obvious prerequisite for such a rapid development in the field of intervention coronary angiography was the establishment of a sufficiently dense network of catheter laboratories and specialized facilities, which provide a highly professional and intensive care for patients. This thesis is focused on three basic objectives: ? To survey and characterize differences in nursing care concerning various complications in patients after SKG / PCI ? To survey bio / psycho / social impacts of complications after SKG / PCI on a patient ? To identify and summarize personal and material prerequisites and requirements to ensure quality nursing care for these complicated conditions The research was conducted by using a qualitative methodology. The methods used were observation, non-standardized interviews and medical and nursing records analyses. The research survey samples on which the investigation was focused were patients with the acute coronary syndrome hospitalized in the coronary care unit in the Cardio Center in České Budějovice, their family members and also the nursing staff providing the comprehensive nursing care. The outcomes of this survey were eleven descriptive case reports characterizing the occurrence of the most frequent complications in patients with ACS after SKG / PCI. To ensure clarity, each case study is complemented by a thought map with an account of the most important nursing interventions in the management of specific acute conditions. The paper also contains a framework analysis of bio / psycho / social impacts of complicated situations on patients. It is interesting to compare this matter from the perspective of nurses and patients, which is seen in correlation graphs. The section describing the organizational and personnel provision is introduced with the characteristics of the medical process and it also contains the list of medical personnel with their qualifications and the length of experience in the Coronary care unit in České Budějovice. Summarization of the instrumental medical equipment is also based on the analysis of previous cases and is accompanied by photographs of the equipment typical and indispensable for the care of patients in the Coronary care unit, which primarily has an informative and complementary character to get an integrated view of the Coronary care unit running and the nursing staff work.
25

Estudo comparativo entre os custos dos tratamentos clínico, cirúrgico ou percutâneo em portadores de doença multiarterial coronária estável - 5 anos de seguimento / Comparative cost analysis for surgical, angioplasty, or medical therapeutics for coronary artery disease - 5-year follow-up

Ricardo D'Oliveira Vieira 06 June 2013 (has links)
Estudo comparativo entre os custos dos tratamentos clínico, cirúrgico ou percutâneo em portadores de doença multiarterial coronária estável - 5 anos de seguimento [tese]. São Paulo: Faculdade de Medicina, Universidade de São Paulo, 2013. INTRODUÇÃO: As principais opções terapêuticas para a doença multiarterial coronária incluem cirurgia de revascularização miocárdica (CRM), intervenção coronária percutânea (ICP) e tratamento clínico (TC). Essas três estratégias terapêuticas apresentam eficácia similar em determinados subgrupos de pacientes. No presente momento, estudos direcionados à análise econômica são escassos, e contemplam, principalmente, os custos comparativos entre as intervenções cirúrgica e percutânea. OBJETIVOS: Analisar, prospectivamente, o custo comparativo das três formas terapêuticas da doença multiarterial coronária estável, durante cinco anos de seguimento. MÉTODOS: Foi computado o custo terapêutico global de 611 pacientes do ensaio clínico The Second Medicine, Angioplasty, or Surgery Study (MASS II), baseado na remuneração provida pelo sistema de saúde suplementar do Instituto do Coração do HC/FMUSP, tomando-se os valores em moeda nacional corrente. Realizou-se, posteriormente, análise de custo-efetividade para o tempo livre de eventos clínicos e o tempo livre de eventos acrescido de tempo livre de angina. RESULTADOS: O TC apresentou 3.79 e 2.07 QALY (quality-adjusted lifeyears); o ICP apresentou 3.59 e 2.77 QALY; e o CRM apresentou 4.4 e 2.81 QALY, respectivamente, para sobrevida livre de eventos e sobrevida livre de eventos e angina. Os custos para sobrevida livre de eventos foram R$ 16.327,80 para TC, R$ 35.940,60 para ICP e R$ 32.873,40 para CRM. A análise pareada dos custos para sobrevida livre de eventos mostrou que houve diferença significante favorecendo TC contra ICP (P < 0,01), e em comparação com CRM (P < 0,01); e CRM versus ICP (P = 0,01). Os custos para sobrevida livre de eventos e angina foram R$ 29.795,40, R$ 46.495,80 e R$ 44.305,20, respectivamente. A comparação pareada dos custos livres de eventos mais livres de angina demonstrou que houve diferença significante favorecendo TC contra ICP (P = 0,04), e em comparação com CRM (P < 0,001). Não houve diferença entre CRM e ICP (P > 0,05). CONCLUSÃO: A análise comparativa entre as diferentes opções terapêuticas desta amostra revelou que TC foi mais custo-efetivo que CRM, e esta, por sua vez, mais custo-efetivo que ICP / BACKGROUND: The therapeutic options for multivessel coronary artery disease are coronary artery bypass graft surgery (CABG), percutaneous coronary intervention (PCI), or medical treatment alone (MT). These three therapeutic strategies present similar efficacy for specific subgroups. At the present moment, economic outcome trials are scant, and contemplate comparative cost between surgical or percutaneous intervention. OBJECTIVE: To analyze, prospectively, the comparative cost from three therapeutic strategies in multivessel coronary artery disease, at 5-year of follow-up. METHODS: We analyzed cumulative costs of 611 patients from clinical trial The Second Medicine, Angioplasty, or Surgery Study (MASS II). The economic analysis is based on remuneration provided by the supplementary health system of the Heart Institute of the Clinical Hospital of FMUSP, expressing these values in Brazilian currency. It was compared to the cumulative costs of each therapeutic strategy in the 5-year follow-up period. A cost-effectiveness analysis was then conducted for event-free survival and event plus angina-free survival. Cost-effectiveness analysis was performed by quality-adjusted life- year (QALY) analysis. RESULTS: Respectively, for event-free survival and event plus angina-free survival, MT presented 3.79 quality-adjusted life-years (QALY) and 2.07 QALY; PCI presented 3.59 and 2.77 QALY; and CABG demonstrated 4.4 and 2.81 QALY. The event-free costs were R$ 16327.80 for MT; R$ 35940.60 for PCI; and R$ 32873.40 for CABG. The paired comparison of the event-free costs showed that there was a significant difference favoring MT versus PCI (P < 0.01) and versus CABG (P < 0.01) and CABG versus PCI (P =0.01). The event-free plus angina-free costs were R$ 29795.40, R$ 46495.80 e R$ 44305.20, respectively. The paired comparison of the event-free plus angina-free costs showed that there was a significant difference favoring MT versus PCI (P =0.04), and versus CABG (P < 0.001); there was no difference between CABG and PCI (P > 0.05). CONCLUSION: The comparative analysis among the different therapeutic strategies demonstrated that MT was more cost-effective than CABG, and this than PCI
26

Statistiques appliquées en chirurgie cardiaque adulte : analyses de survie et applications du “propensity score”

Stevens, Louis-Mathieu 05 1900 (has links)
L'objectif principal de ce travail est d’étudier en profondeur certaines techniques biostatistiques avancées en recherche évaluative en chirurgie cardiaque adulte. Les études ont été conçues pour intégrer les concepts d'analyse de survie, analyse de régression avec “propensity score”, et analyse de coûts. Le premier manuscrit évalue la survie après la réparation chirurgicale de la dissection aigüe de l’aorte ascendante. Les analyses statistiques utilisées comprennent : analyses de survie avec régression paramétrique des phases de risque et d'autres méthodes paramétriques (exponentielle, Weibull), semi-paramétriques (Cox) ou non-paramétriques (Kaplan-Meier) ; survie comparée à une cohorte appariée pour l’âge, le sexe et la race utilisant des tables de statistiques de survie gouvernementales ; modèles de régression avec “bootstrapping” et “multinomial logit model”. L'étude a démontrée que la survie s'est améliorée sur 25 ans en lien avec des changements dans les techniques chirurgicales et d’imagerie diagnostique. Le second manuscrit est axé sur les résultats des pontages coronariens isolés chez des patients ayant des antécédents d'intervention coronarienne percutanée. Les analyses statistiques utilisées comprennent : modèles de régression avec “propensity score” ; algorithme complexe d'appariement (1:3) ; analyses statistiques appropriées pour les groupes appariés (différences standardisées, “generalized estimating equations”, modèle de Cox stratifié). L'étude a démontrée que l’intervention coronarienne percutanée subie 14 jours ou plus avant la chirurgie de pontages coronariens n'est pas associée à des résultats négatifs à court ou long terme. Le troisième manuscrit évalue les conséquences financières et les changements démographiques survenant pour un centre hospitalier universitaire suite à la mise en place d'un programme de chirurgie cardiaque satellite. Les analyses statistiques utilisées comprennent : modèles de régression multivariée “two-way” ANOVA (logistique, linéaire ou ordinale) ; “propensity score” ; analyses de coûts avec modèles paramétriques Log-Normal. Des modèles d’analyse de « survie » ont également été explorés, utilisant les «coûts» au lieu du « temps » comme variable dépendante, et ont menés à des conclusions similaires. L'étude a démontrée que, après la mise en place du programme satellite, moins de patients de faible complexité étaient référés de la région du programme satellite au centre hospitalier universitaire, avec une augmentation de la charge de travail infirmier et des coûts. / The main objective of this work is to study in depth advanced biostatistical techniques in adult cardiac surgery outcome research. The studies were designed to incorporate the concepts of survival analysis, regression analysis with propensity score, and cost analysis. The first manuscript assessed survival, and cardiovascular specific mortality, following surgical repair of acute ascending aortic dissection. The statistical analyses included survival analyses with multiphase parametric hazard regression and other parametric (exponential, Weibull), semi-parametric (Cox) or non-parametric models (Kaplan Meier), comparison with the survival of a matched cohort for age, gender and race using State lifetables, and modelization with bootstrapping and multinomial logit models. The study showed that the early and late survival following surgical repair has improved progressively over 25 years in association with noticeable changes in surgical techniques and preoperative diagnostic testing. The second manuscript focused on outcomes following isolated coronary artery bypass grafting in patients with a history of percutaneous coronary intervention. The statistical analyses included multivariable regression models with propensity score, complex matching algorithm (1:3) and appropriate statistical analyses for matched groups (standardized differences, generalized estimating equations, and survival analyses with stratified proportional hazards models). The study showed that remote prior percutaneous coronary intervention more than 14 days before coronary artery bypass grafting surgery was not associated with adverse outcomes at short or long-term follow-up. The third manuscript evaluated the financial consequences and the changes in case mix that occurred at an academic medical center subsequent to the implementation of a satellite cardiac surgery program. The statistical analyses included two-way ANOVA multivariable regression models (logistic, linear or ordinal), propensity score, and cost analyses using Log-Normal parametric models. “Survival” analyses models were also explored, using “cost” instead of “time” as the outcome of interest, and led to similar conclusions. The study showed that, after implementation of the satellite cardiac surgery program, fewer patients of lower complexity came to the academic medical center from the satellite program area, with a significant increase in nursing workload and costs.
27

Statistiques appliquées en chirurgie cardiaque adulte : analyses de survie et applications du “propensity score”

Stevens, Louis-Mathieu 05 1900 (has links)
L'objectif principal de ce travail est d’étudier en profondeur certaines techniques biostatistiques avancées en recherche évaluative en chirurgie cardiaque adulte. Les études ont été conçues pour intégrer les concepts d'analyse de survie, analyse de régression avec “propensity score”, et analyse de coûts. Le premier manuscrit évalue la survie après la réparation chirurgicale de la dissection aigüe de l’aorte ascendante. Les analyses statistiques utilisées comprennent : analyses de survie avec régression paramétrique des phases de risque et d'autres méthodes paramétriques (exponentielle, Weibull), semi-paramétriques (Cox) ou non-paramétriques (Kaplan-Meier) ; survie comparée à une cohorte appariée pour l’âge, le sexe et la race utilisant des tables de statistiques de survie gouvernementales ; modèles de régression avec “bootstrapping” et “multinomial logit model”. L'étude a démontrée que la survie s'est améliorée sur 25 ans en lien avec des changements dans les techniques chirurgicales et d’imagerie diagnostique. Le second manuscrit est axé sur les résultats des pontages coronariens isolés chez des patients ayant des antécédents d'intervention coronarienne percutanée. Les analyses statistiques utilisées comprennent : modèles de régression avec “propensity score” ; algorithme complexe d'appariement (1:3) ; analyses statistiques appropriées pour les groupes appariés (différences standardisées, “generalized estimating equations”, modèle de Cox stratifié). L'étude a démontrée que l’intervention coronarienne percutanée subie 14 jours ou plus avant la chirurgie de pontages coronariens n'est pas associée à des résultats négatifs à court ou long terme. Le troisième manuscrit évalue les conséquences financières et les changements démographiques survenant pour un centre hospitalier universitaire suite à la mise en place d'un programme de chirurgie cardiaque satellite. Les analyses statistiques utilisées comprennent : modèles de régression multivariée “two-way” ANOVA (logistique, linéaire ou ordinale) ; “propensity score” ; analyses de coûts avec modèles paramétriques Log-Normal. Des modèles d’analyse de « survie » ont également été explorés, utilisant les «coûts» au lieu du « temps » comme variable dépendante, et ont menés à des conclusions similaires. L'étude a démontrée que, après la mise en place du programme satellite, moins de patients de faible complexité étaient référés de la région du programme satellite au centre hospitalier universitaire, avec une augmentation de la charge de travail infirmier et des coûts. / The main objective of this work is to study in depth advanced biostatistical techniques in adult cardiac surgery outcome research. The studies were designed to incorporate the concepts of survival analysis, regression analysis with propensity score, and cost analysis. The first manuscript assessed survival, and cardiovascular specific mortality, following surgical repair of acute ascending aortic dissection. The statistical analyses included survival analyses with multiphase parametric hazard regression and other parametric (exponential, Weibull), semi-parametric (Cox) or non-parametric models (Kaplan Meier), comparison with the survival of a matched cohort for age, gender and race using State lifetables, and modelization with bootstrapping and multinomial logit models. The study showed that the early and late survival following surgical repair has improved progressively over 25 years in association with noticeable changes in surgical techniques and preoperative diagnostic testing. The second manuscript focused on outcomes following isolated coronary artery bypass grafting in patients with a history of percutaneous coronary intervention. The statistical analyses included multivariable regression models with propensity score, complex matching algorithm (1:3) and appropriate statistical analyses for matched groups (standardized differences, generalized estimating equations, and survival analyses with stratified proportional hazards models). The study showed that remote prior percutaneous coronary intervention more than 14 days before coronary artery bypass grafting surgery was not associated with adverse outcomes at short or long-term follow-up. The third manuscript evaluated the financial consequences and the changes in case mix that occurred at an academic medical center subsequent to the implementation of a satellite cardiac surgery program. The statistical analyses included two-way ANOVA multivariable regression models (logistic, linear or ordinal), propensity score, and cost analyses using Log-Normal parametric models. “Survival” analyses models were also explored, using “cost” instead of “time” as the outcome of interest, and led to similar conclusions. The study showed that, after implementation of the satellite cardiac surgery program, fewer patients of lower complexity came to the academic medical center from the satellite program area, with a significant increase in nursing workload and costs.
28

Détermination automatique de l'incidence optimale pour l'observation des lésions coronaires en imagerie rotationnelle R-X / Automatic determination of optimal viewing angle for the coronary lesion observation in rotationnal X-ray angiography

Feuillâtre, Hélène 10 June 2016 (has links)
Les travaux de cette thèse s’inscrivent dans le cadre du planning de traitements minimalement invasifs des lésions des artères coronaires. Le cardiologue réalise un examen coronarographique, puis dans la continuité, une angioplastie transluminale. L’angiographie rotationnelle à rayons X permet de visualiser sous différentes incidences 2D la lumière des artères coronaires sur plusieurs cycles cardiaques et aussi d’obtenir une reconstruction 3D+T des arbres coronaires. A partir de cette séquence, notre objectif est de déterminer automatiquement une incidence optimale 2D du segment sténosé compatible avec les angles du C-arm afin d’aider le cardiologue lors de l’intervention.Différentes étapes sont considérées pour calculer la position angulaire optimale du C-arm. Afin de suivre la zone de lésion durant le cycle cardiaque, une première méthode est proposée pour mettre en correspondance tous les arbres de la séquence 3D+T. Tout d’abord, un appariement deux à deux des arbres successifs est réalisé afin de construire un arbre d’union. Ces derniers sont ensuite fusionnés afin d’obtenir un arbre mosaïque représentant l’arbre le plus complet de la séquence. L’utilisation de mesures de similarités géométriques et hiérarchiques ainsi que l’insertion de nœuds artificiels permet de prendre en compte les différents mouvements non-rigides des artères coronaires subits au cours du cycle cardiaque et les variations topologiques dû à leurs extractions. Cet appariement nous permet de proposer une deuxième méthode afin d’obtenir une vue angiographique 2D optimale de la zone de lésion tout le long du cycle cardiaque. Cette incidence est proposée spécifiquement pour trois types de région d’intérêt (segment unique, segment multiple ou bifurcation) et est calculée à partir de quatre critères (raccourcissement, chevauchement interne et externe ou angle d’ouverture de bifurcation). Une vue 2D déployée du segment projeté avec le moins de superposition avec les structures vasculaires avoisinantes est obtenue. Nous donnons également la possibilité au cardiologue d’avoir une incidence optimale privilégiant soit le déploiement du stent ou soit le guidage d’outils de la racine de l’arbre à la zone sténosée. Nos différents algorithmes ont été évalués sur une séquence réelle de 10 phases segmentées à partir d’un CT et de 41 séquences simulées. / The thesis work deals with the planning of minimally invasive surgery of coronary artery lesions. The physician performs a coronarography following by a percutaneous transluminal angioplasty. The X-ray rotational angiography permits to visualize the lumen artery under different projection angles in several cardiac cycles. From these 2D projections, a 3D+T reconstruction of coronary arteries can be obtained. Our goal is to determine automatically from this 3D+T sequence, the optimal angiographic viewing angle of the stenotic segment. Several steps are proposed to compute the optimal angular position of the C-arm. Firstly, a mosaic-based tree matching algorithm of the 3D+T sequence is proposed to follow the stenotic lesion in the whole cardiac cycle. A pair-wise inexact tree matching is performed to build a tree union between successive trees. Next, these union trees are merged to obtain the mosaic tree which represents the most complete tree of the sequence. To take into account the non-rigid movement of coronary arteries during the cardiac cycle and their topology variations due to the 3D reconstruction or segmentation, similarity measures based on hierarchical and geometrical features are used. Artificial nodes are also inserted. With this global tree sequence matching, we propose secondly a new method to determine the optimal viewing angle of the stenotic lesion throughout the cardiac cycle. This 2D angiographic view which is proposed for three regions of interest (single segment, multiple segment or bifurcation) is computed from four criteria: the foreshortening, the external and internal overlap and the bifurcation opening angle rates. The optimal view shows the segment in its most extended and unobstructed dimension. This 2D view can be optimal either for the deployment of the stent or for the catheter guidance (from the root to the lesion). Our different algorithms are evaluated on real sequence (CT segmentation) and 41 simulated sequences.

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