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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

Estratificação de risco para eventos cardíacos maiores em pacientes submetidos ao implante de stents farmacológicos. Escore DESIRE / Cardiovascular Risk Stratification for Patients Treated with Drug-eluting Stents: Development and Validation of the DESIRE score

Adriana Costa Moreira 10 May 2017 (has links)
INTRODUÇÃO: A estratificação de risco, pré intervenção coronária percutânea, é um elemento-chave para auxiliar na tomada de decisão oferecendo o nível de expectativas de resultados imediatos e tardios. Esta investigação tem como objetivo desenvolver o escore DESIRE para predizer o risco de ocorrência de eventos cardíacos maiores(ECM) em pacientes(P) submetidos ao implante de stents farmacológicos(SF) na prática clínica diária. MÉTODOS: Desde 2002 todos os pacientes consecutivos, tratados com 1 SF , foram incluídos no Registro DESIRE (Drug-Eluting Stents In REal world), não-randomizado. Desenvolvemos o escore DESIRE, a partir da análise retrospectiva dos dados dos P incluídos entre janeiro de 2007 e dezembro de 2012 uma vez que esta população representava melhor a prática contemporânea da cardiologia intervencionista. As associações das variáveis com os eventos foram testadas pelos testes chi-quadrado e t de Student. Devido às diferenças entre as fases analisadas, decidimos por dois modelos de predição de riscos: hospitalar (Regressão logística) e tardio (Cox) estimando o tempo até o primeiro evento. Após o desenvolvimento, o escore foi aplicado prospectivamente nos pacientes incluídos entre janeiro de 2013 e dezembro de 2014. As estimativas de risco obtidas foram comparadas às taxas de ECM observadas, validando o escore DESIRE nas duas fases. RESULTADOS: 4.061 P compõem a população do estudo sendo que destes, 2.863 P constituem a coorte B1 que foi utilizada para o desenvolvimento do escore e 1.198 P na coorte B2 na qual o escore foi aplicado e validado. As variáveis e seus respectivos pontos para o escore DESIRE hospitalar que variou de 0 a 37 pontos foram: idade em anos (<=49= 0; 50 - 59=1; 60 a 69=2; 70 a 79=4; <= 80=6); cirurgia de revascularização miocárdica prévia(1); doença vascular periférica (5); insuficiência renal (3); síndrome coronária aguda (3); doença multiarterial (3); ponte de safena (6); lesão com trombo (5) e lesão longa (5). Compuseram o escore DESIRE tardio (0 a 45 pontos) as seguintes variáveis: diabete melito com medicação oral (4) ou com insulina (9); cirurgia de revascularização miocárdica prévia (2); doença vascular periférica (6); síndrome coronária aguda (5); doença multiarterial (4); FE<40% (6); ponte de safena (8) e vaso de pequeno calibre (5). Definimos 3 faixas de risco para cada um dos escores categorizando os pacientes de acordo com a pontuação obtida em baixo, intermediário e alto risco para ECM sendo para a fase hospitalar. Ambos os escores apresentaram acurácia para predizer eventos próxima a 70%. CONCLUSÃO: Baseados em dados do Registro do \"mundo real\" foi possível desenvolver o Escore DESIRE que permitiu a adequada estratificação do risco de eventos cardíacos maiores após o implante de SF, nas fases hospitalar e tardia. A partir destas estimativas de risco é possível consubstanciar as escolhas terapêuticas. / BACKGROUND: Risk stratification before percutaneous coronary intervention is a key element to assist in decision making offering the level of expectations for immediate and late outcomes. This research aims to develop the DESIRE score to predict the risk of major cardiac events (MACE) in patients (P) who underwent drug-eluting stent implantation in daily clinical practice. METHODS: Since 2002 all consecutive patients treated with> 1 SF in a single center were included in the non-randomized DESIRE (Drug-Eluting Stents In the Real world) Registry. We developed the DESIRE score based on a retrospective analysis of the patients included between January 2007 and December 2012, since this population better represented the contemporary practice of interventional cardiology. The associations of the variables with the events were tested by chi-square and Student\'s t tests. Due to the differences between the analyzed phases, we decided on two models of risk prediction: hospital (Logistic Regression) and late (Cox) estimating the time until the first event. After the development, the score was applied prospectively in the patients included between January 2013 and December 2014. The risk estimates obtained were compared to the observed MACE rates, validating the DESIRE score in the two phases. RESULTS: A total of 4,061 patients were included in the study population. Of these, 2,863 P were the B1 cohort that was used for the development of the score and 1,198 P in the B2 cohort in which the score was applied and validated. The variables and their respective points for the hospital DESIRE score ranged from 0 to 37 points were: age in years <=49= 0; 50 - 59=1; 60 a 69=2; 70 a 79=4; <= 80=6); Previous myocardial revascularization surgery (1); Peripheral vascular disease (5); Cronic kidney dysfunction (3); Acute coronary syndrome (3); Multivessel disease (3) Saphenousvenous graft (6); lesion with thrombus (5) and Long lesion (5);The following variables composed the late DESIRE score (0 to 45 points): Diabetes mellitus with oral medication (4) or with insulin (9); previous myocardial revascularization surgery (2); Peripheral vascular disease (6); Acute coronary syndrome (5); Multivessel disease (4); ejection fraction <40% (6); saphenous vein graft (8) and small vessel (5). We defined 3 risk ranges for each of the scores by categorizing the patients according to the low, intermediate and high-risk scores for ECM being for the hospital phase. Both scores had accuracy to predict MACE close to 70%. CONCLUSION: Based on data from the \"real world\" registry, it was possible to develop the DESIRE score that allowed the adequate stratification of the risk of major cardiac events after the SF implantation in the hospital and late phases. From these risk estimates it is possible to substantiate the therapeutic choices.
22

Avaliação tardia dos stents liberadores de Biolimus A9® pela tomografia de coerência óptica: análise da cobertura tecidual e da aposição das hastes / Long-term follow-up Biolimus A9TM stents with optical coherence tomography: strut apposition and tissue coverage analysis

Rodolfo Staico 04 July 2011 (has links)
Introdução: Os stents farmacológicos (SF) de primeira geração surgiram com o intuito de reduzir as taxas de reestenose intra-stent e de revascularização da lesão-alvo, sendo mais eficazes quando comparados aos stents não-farmacológicos (SNF), porém com aumento de risco de trombose do stent (TS) muito tardia. A cobertura tecidual incompleta e a má aposição tardia das hastes dos stents podem estar vinculadas à TS. O SF de segunda geração BioMatrix®, que utiliza um polímero bioabsorvível, surgiu na expectativa de redução da TS. Devido à alta acurácia e reprodutibilidade e à análise precisa da cobertura tecidual e da aposição das hastes dos stents, a tomografia de coerência óptica (TCO) vem se tornando um método útil na análise desses aspectos. O objetivo desse estudo foi avaliar a cobertura tecidual e a aposição das hastes do SF BioMatrix® após longo período do implante. Métodos: Vinte pacientes submetidos ao implante do SF BioMatrix® (n = 15) ou do SNF S-Stent® (n = 5) foram acompanhados por um período mínimo de cinco anos e avaliados por meio da angiografia coronária quantitativa (ACQ), da ultrassonografia intracoronária (USIC) e da TCO. Para a análise estatística, foram utilizados os programas SPSS® versão 16.0 e SAS versão 9.2. O valor de p < 0,05 era considerado estatisticamente significante. As variáveis categóricas foram expressas em números absolutos e porcentuais e comparadas pelo teste exato de Fisher. As variáveis contínuas foram expressas em média e desvio padrão e/ou mediana e intervalo interquartílico e foram comparadas pelo teste não paramétrico de Mann-Whitney. Resultados: A ACQ demonstrou diferença, porém não significativa na perda tardia da luz entre o SF BioMatrix® e o S-Stent® [0,40 (0,21; 0,77) mm vs 0,68 (0,66; 0,82) mm, p = 0,205]. Os pacientes tratados com o SF BioMatrix® apresentaram porcentual de obstrução do stent significativamente menor quando comparados àqueles que receberam o S-Stent® [5,6 (4,4; 9,7)% vs 28,6 (24,7; 29,0)%, p =0,001]. A análise da TCO demonstrou 126 (8,7%) hastes não cobertas nos stents BioMatrix® e 23 (4,0%) nos S-Stents® (p = 0,297), estando a maioria delas bem apostas (117/126 e 21/23, respectivamente, p = 0,292). Apenas nove (0,6%) hastes nos SF e duas (0,4%) hastes nos SNF estavam simultaneamente sem cobertura tecidual e mal apostas (p = 0,924). No grupo BioMatrix®, apenas 1 (11,1%) paciente teve todas as hastes cobertas. Já no grupo S-Stent, 66,7% dos pacientes (2/3) apresentaram cobertura completa das hastes (p = 0,127). Conclusões: A avaliação tardia do SF BioMatrix® pela TCO mostrou cobertura tecidual e aposição em quase a totalidade de suas hastes, de maneira similar àquela encontrada nos SNF S-Stents®. / Introduction: First generation drug-eluting stents (DES) have emerged as a strategy to prevent in-stent restenosis and the need of target-vessel revascularization when compared to bare metal stents (BMS); but at the expense of a higher risk of very late stent thrombosis (ST). Uncovered and malapposed struts may be associated with both late and very late ST. It has been postulated that the second generation DES, the biolimus-eluting stent BioMatrixTM with biodegradable polymer, may reduce the incidence of ST. Given its high accuracy and reproducibility with precise analysis of the complete strut apposition and strut coverage, the optic coherence tomography (OCT) has been extensively used for stent analysis. The aim of this study was to assess the struts coverage and apposition of DES BioMatrixTM in a long-term follow up. Methods: Twenty patients undergoing a BioMatrixTM (n = 15) or BMS S-StentTM (n = 5) implantation were followed up for a period of at least five years and evaluated by means of OCT, quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). All statistical analyses were performed using SPSSTM (v.16.0) and SAS (v.9.2) software. Statistical significance was considered at p values < 0.05. Categorical variables were expressed as counts and percentages, and continuous variables as mean SD and/or median and interquartile range. For per-patient level comparison, the difference between two stent types was evaluated by nonparametric Mann-Whitney U test while categorical variables were evaluated by the Fisher exact test. Results: QCA analysis showed no differences in the occurrence of intrastent late loss between the groups [0.40 (0.21; 0.77) mm vs 0.68 (0.66; 0.82) mm, p = 0.205 for BioMatrixTM and S-StentsTM, respectively]. The vessel, stent and lumen volumes assessed by IVUS after the procedure and 5 years later were similar between the two groups. Patients treated with BioMatrixTM had significantly less stent obstruction percentage when compared to those treated with S-StentTM [5.6 (4.4; 9.7)% vs 28.6 (24.7; 29.0)%, p = 0.001]. OCT analysis demonstrated 126 (8.7%) uncovered struts in the BioMatrixTM group compared to 23 (4.0%) in the S-StentsTM group (p = 0.297), being the majority of them well apposed (117/126 and 21/23, respectively, p = 0.292). Only 9 (0.6%) struts in the DES and 2 (0.4%) struts in the BMS groups were imultaneously uncovered and malapposed (p = 0.924). Among the BioMatrixTM patients, 55.6% (5/9) had more than 95% of covered struts and in only 1 (11.1%) patient all struts were covered. On the other hand, among the S-StentTM patients, 66.7% (2/3) had complete covered struts (p = 0.127). Conclusion: Long term assessment of DES BioMatrixTM by OCT showed tissue coverage and apposition in almost all struts, similary to those found in the BMS S-StentsTM.
23

POSS-Based Biodegradable Polymers for Stent Applications: Electroprocessing, Characterization and Controlled Drug Release

Guo, Qiongyu January 2010 (has links)
No description available.
24

Influência da composição da placa aterosclerótica nos resultados da angioplastia com stent coronariano / Influence of atherosclerotic plaque composition on the results of coronary angioplasty with stent implantation

Galon, Micheli Zanotti 07 December 2017 (has links)
Fundamentos: A caracterização precisa da interação da placa aterosclerótica no momento do implante do stent é crucial para o entendimento da complacência e da cicatrização vasculares. Objetivamos investigar se a composição da placa avaliada pela tomografia de coerência óptica (OCT), influencia as alterações agudas no procedimento índice do implante do stent e na cicatrização vascular no seguimento tardio. Métodos: Os pacientes tratados com um único tipo de stent eluidor de fármaco (cromo cobalto, eluidor de sirolimus e polímero bioabsorvível) foram incluídos prospectivamente, seguindo um protocolo com etapas de dilatações progressivas do vaso. As imagens de OCT sequenciais foram realizadas no procedimento índice (basal e a cada etapa do protocolo) e no seguimento tardio, co-registradas e analisadas a cada 0,6mm. A avaliação semiquantitativa da placa foi realizada dividindo-se secções transversas em 4 quadrantes, com cada quadrante rotulado de acordo com o seu componente mais prevalente (fibrótico, calcificado, lipídico, normal). A interação stent-vaso avaliada pela OCT foi utilizada como indicador substituto para lesão e cicatrização vasculares após o implante do stent. Resultados: Um total de 22 lesões (1stent/lesão) de 20 pacientes e 2298 seções transversas de OCT foram analisadas no procedimento índice. O reestudo com OCT foi realizado em 17 pacientes e 19 lesões (86%). O componente de placa predominante foi fibrótico (fibrótico = 46.84 ± 16%; lipídico = 17.63 ± 10.72%; calcificado = 4.63 ± 5.9%; normal = 29.16 ± 12.24; não analizável=1.74 ± 5.35%). Houve um aumento nas áreas da luz (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) e do stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001), com um aumento na área do prolapso tecidual (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segmentos com muito tecido fibrocalcificado tiveram áreas luminais menores ao longo das etapas da intervenção. Por outro lado, placas com muito conteúdo lipídico ou vaso normal tiveram maiores ganhos nas medidas das áreas luminais mínimas ao longo das dilatações sequenciais. Além disso, placas com muito tecido fibrocalcificado no momento basal apresentaram menor crescimento neointimal no seguimento tardio, enquanto que o grau de conteúdo lipídico e de vaso normal não tiveram impacto sobre a formação do tecido neointimal. Os indicadores substitutos de lesão vascular após o implante do stent correlacionaram-se significativamente com o crescimento neointimal no seguimento tardio. Conclusões: A composição tecidual das placas subjacentes influencia significativamente o comportamento mecânico agudo e a longo prazo dos vasos coronarianos submetidos ao implante de stent. Além disso, a lesão vascular após o implante do stent está potencialmente ligada ao futuro crescimento neointimal no seguimento tardio / Background Accurate characterization of atherosclerotic plaque interaction during stent deployment is crucial to understand vascular compliance and healing. We sought to determine whether plaque composition assessed by optical coherence tomography (OCT), influences acute changes at index procedure and vascular healing at follow up. Methods Patients treated with a single drug-eluting stent type (cobalt chromium with bioabsorbable polymer eluting sirolimus stent) were prospectively included, following a pre-defined step-by-step progressive vessel dilatation. Sequential OCT imaging were performed at the index procedure (baseline and at each time point of the protocol) and at follow up, co-registered and analyzed every 0.6mm for quantitative measurements. Semi-quantitative plaque assessment was performed at baseline by dividing cross-sections into 4 quadrants, with each quadrant labeled according to its most prevalent component (fibrotic, calcific, lipid). OCT assessments of stent-vessel interactions were used as a surrogate for vessel injury and healing after stent implantation. Results A total of 22 lesions (1stent/lesion) of 20 patients and 2298 OCT crosssections were analyzed at the index procedure. For an average of 19.7 months (591.88 ± 60.52 days), 17 of the patients and 19 lesions (86%) underwent OCT imaging at follow up. The predominant percentage plaque component was fibrotic (fibrotic = 46.84 ± 16%; lipid = 17.63 ± 10.72%; calcific = 4.63 ± 5.9%; normal = 29.16 ± 12.24; non-analyzable = 1.74 ± 5.35%). There was an increase in lumen (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) and stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001) areas, with an increase in tissue prolapse area (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segments with high fibrocalcific content tended to have decreased minimal luminal areas along the intervention time-points. Conversely, plaques with high lipid content had increased minimal luminal areas during sequential dilatations. Moreover, plaques with high fibrocalcific tissue at baseline had significantly smaller neointimal growth at follow-up, whereas the degree of lipid content or normal tri-layered vessel had no impact on neointimal formation. OCT surrogates of vessel injury after coronary stenting significantly correlated with neointimal growth at follow-up. Conclusions: Tissue composition of underlying plaques significantly influences the acute mechanical and the long-term behavior of coronary vessels undergoing stent implantation. In addition, vessel injury after coronary stenting is potentially linked to future neointimal growth at follow-up
25

Influência da composição da placa aterosclerótica nos resultados da angioplastia com stent coronariano / Influence of atherosclerotic plaque composition on the results of coronary angioplasty with stent implantation

Micheli Zanotti Galon 07 December 2017 (has links)
Fundamentos: A caracterização precisa da interação da placa aterosclerótica no momento do implante do stent é crucial para o entendimento da complacência e da cicatrização vasculares. Objetivamos investigar se a composição da placa avaliada pela tomografia de coerência óptica (OCT), influencia as alterações agudas no procedimento índice do implante do stent e na cicatrização vascular no seguimento tardio. Métodos: Os pacientes tratados com um único tipo de stent eluidor de fármaco (cromo cobalto, eluidor de sirolimus e polímero bioabsorvível) foram incluídos prospectivamente, seguindo um protocolo com etapas de dilatações progressivas do vaso. As imagens de OCT sequenciais foram realizadas no procedimento índice (basal e a cada etapa do protocolo) e no seguimento tardio, co-registradas e analisadas a cada 0,6mm. A avaliação semiquantitativa da placa foi realizada dividindo-se secções transversas em 4 quadrantes, com cada quadrante rotulado de acordo com o seu componente mais prevalente (fibrótico, calcificado, lipídico, normal). A interação stent-vaso avaliada pela OCT foi utilizada como indicador substituto para lesão e cicatrização vasculares após o implante do stent. Resultados: Um total de 22 lesões (1stent/lesão) de 20 pacientes e 2298 seções transversas de OCT foram analisadas no procedimento índice. O reestudo com OCT foi realizado em 17 pacientes e 19 lesões (86%). O componente de placa predominante foi fibrótico (fibrótico = 46.84 ± 16%; lipídico = 17.63 ± 10.72%; calcificado = 4.63 ± 5.9%; normal = 29.16 ± 12.24; não analizável=1.74 ± 5.35%). Houve um aumento nas áreas da luz (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) e do stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001), com um aumento na área do prolapso tecidual (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segmentos com muito tecido fibrocalcificado tiveram áreas luminais menores ao longo das etapas da intervenção. Por outro lado, placas com muito conteúdo lipídico ou vaso normal tiveram maiores ganhos nas medidas das áreas luminais mínimas ao longo das dilatações sequenciais. Além disso, placas com muito tecido fibrocalcificado no momento basal apresentaram menor crescimento neointimal no seguimento tardio, enquanto que o grau de conteúdo lipídico e de vaso normal não tiveram impacto sobre a formação do tecido neointimal. Os indicadores substitutos de lesão vascular após o implante do stent correlacionaram-se significativamente com o crescimento neointimal no seguimento tardio. Conclusões: A composição tecidual das placas subjacentes influencia significativamente o comportamento mecânico agudo e a longo prazo dos vasos coronarianos submetidos ao implante de stent. Além disso, a lesão vascular após o implante do stent está potencialmente ligada ao futuro crescimento neointimal no seguimento tardio / Background Accurate characterization of atherosclerotic plaque interaction during stent deployment is crucial to understand vascular compliance and healing. We sought to determine whether plaque composition assessed by optical coherence tomography (OCT), influences acute changes at index procedure and vascular healing at follow up. Methods Patients treated with a single drug-eluting stent type (cobalt chromium with bioabsorbable polymer eluting sirolimus stent) were prospectively included, following a pre-defined step-by-step progressive vessel dilatation. Sequential OCT imaging were performed at the index procedure (baseline and at each time point of the protocol) and at follow up, co-registered and analyzed every 0.6mm for quantitative measurements. Semi-quantitative plaque assessment was performed at baseline by dividing cross-sections into 4 quadrants, with each quadrant labeled according to its most prevalent component (fibrotic, calcific, lipid). OCT assessments of stent-vessel interactions were used as a surrogate for vessel injury and healing after stent implantation. Results A total of 22 lesions (1stent/lesion) of 20 patients and 2298 OCT crosssections were analyzed at the index procedure. For an average of 19.7 months (591.88 ± 60.52 days), 17 of the patients and 19 lesions (86%) underwent OCT imaging at follow up. The predominant percentage plaque component was fibrotic (fibrotic = 46.84 ± 16%; lipid = 17.63 ± 10.72%; calcific = 4.63 ± 5.9%; normal = 29.16 ± 12.24; non-analyzable = 1.74 ± 5.35%). There was an increase in lumen (10atm = 5.5 (4.5 - 7.4) mm2, 14-16atm = 6.0 (4.7 - 7.70) mm2, 20atm = 6.7 (5.5 - 8.2) mm2; P < 0.001) and stent (10atm = 5.2 (4.3 - 7.0) mm2, 14-16atm = 5.7 (4.5 - 7.5) mm2, 20atm = 6.5 (5.3 - 7.9) mm2; P < 0.001) areas, with an increase in tissue prolapse area (10atm =0.09 (0.06 - 0.12) mm2, 14-16atm =0.10 (0.06 - 0.15) mm2, 20atm =0.15 (0.08 - 0.20) mm2; P < 0.01). Segments with high fibrocalcific content tended to have decreased minimal luminal areas along the intervention time-points. Conversely, plaques with high lipid content had increased minimal luminal areas during sequential dilatations. Moreover, plaques with high fibrocalcific tissue at baseline had significantly smaller neointimal growth at follow-up, whereas the degree of lipid content or normal tri-layered vessel had no impact on neointimal formation. OCT surrogates of vessel injury after coronary stenting significantly correlated with neointimal growth at follow-up. Conclusions: Tissue composition of underlying plaques significantly influences the acute mechanical and the long-term behavior of coronary vessels undergoing stent implantation. In addition, vessel injury after coronary stenting is potentially linked to future neointimal growth at follow-up
26

Endoprothèses vasculaires biorésorbables dans la revascularisation coronarienne : traitement de la coronaropathie extensive et caractéristiques angiographiques de la resténose

El Yamani, Mohammed El Mehdi 12 1900 (has links)
Il y a plus de 40 ans, la cardiologie interventionnelle a vu le jour et n’a cessé de révolutionner la prise en charge de l’athérosclérose coronarienne. Les endoprothèses vasculaires biorésorbables (BVS) avaient été conçues pour pallier les risques liés à la présence permanente de tuteurs métalliques dans les artères. En principe, ils fournissent de manière transitoire un soutien mécanique pour le scellement des dissections et la prévention du vasospasme et du remodelage constrictif en plus d’une élution médicamenteuse avant de se résorber et restaurer la vasomotricité coronarienne. L’enthousiasme autour des endoprothèses biorésorbables ABSORB™ était mitigé par un risque soutenu de thrombose du tuteur. Ce mémoire traitera en premier lieu des bases moléculaires de l’athérosclérose. Il abordera ensuite la prise en charge de la coronaropathie athérosclérotique ainsi que l’histoire de la cardiologie interventionnelle et ses différentes révolutions. Ensuite, deux études cliniques ont été conduites dans le cadre de ce travail et seront présentées. La première étude évalue le rôle du BVS dans la revascularisation de la coronaropathie extensive (multivaisseaux ou diffuse) et a montré que, dans un contexte aussi peu favorable au déploiement d’un tuteur coronarien, ABSORB™ a présenté des résultats cliniques acceptables à très long terme comparativement aux tuteurs métalliques de deuxième génération. La deuxième étude s’intéresse quant à elle aux caractéristiques angiographiques de resténose des BVS. Elle a démontré qu’à long terme, la resténose des BVS devient de plus en plus diffuse, et était associée à des issues cliniques moins favorables. Le dernier chapitre de ce mémoire se constitue d’une ouverture conclusive présentant les différentes endoprothèses biorésorbables actuellement à l’étude ou en cours de développement en soulignant leurs principales différences avec ABSORB™. / More than 40 years ago, interventional cardiology was born and has continued to revolutionize the management of coronary atherosclerosis. Bioresorbable Vascular Scaffolds (BVS) were designed to alleviate the risks associated with the permanent presence of metal stents in the arteries. In theory, they provide a transient mechanical support for sealing dissections and preventing vasospasm and constrictive remodeling in addition to a drug-eluting function before complete bioresorption and restoration of coronary vasomotion. Enthusiasm around the ABSORB™ bioresorbable scaffold was mitigated by a sustained risk of scaffold thrombosis. This thesis will first review the molecular basis of atherosclerosis. It will then discuss the management of atherosclerotic coronary artery disease, the history of interventional cardiology and its multiple revolutions. Then, two clinical studies that were conducted as part of this work will be presented. The first study that evaluates the role of BVS in the revascularization of extensive coronary artery disease (multivessel or diffuse) showed that, in such an unfavorable context for the deployment of a coronary stent, ABSORB™ has shown acceptable clinical results in the very long term compared to second generation drug-eluting stents. The second study focuses on the angiographic patterns of BVS restenosis. It showed that in the long term, the pattern of restenosis tended to be more diffuse than focal and that restenosis was associated with less favorable clinical outcomes. The final chapter of this thesis presents the different bioresorbable scaffolds currently under study or under development while highlighting their main differences with ABSORB™.

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