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Neufeld, Ina [Verfasser]. "Schrittmacherdaten nach TAVI-Prozedur / Ina Neufeld." Ulm : Universität Ulm, 2020. http://d-nb.info/120371629X/34.
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Convelbo, Channing. "Mise au point de nouvelles méthodes d’analyse du traumatisme valvulaire des bioprothèses percutanées." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC0010/document.
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Le remplacement valvulaire aortique percutané (TAVI) est une thérapie qui s’impose de plus en plus chez les patients porteurs d’une sténose aortique sévère. Toutefois, un nombre croissant d’études démontre que l’utilisation, crimping (sertissage) et déploiement, de ces bioprothèses est induit une altération de la structure de leurs feuillets péricardiques. Ce qui soulève la question de la durabilité à long-terme de ces dispositifs.Dans les travaux de cette thèse, nous avons développé des outils permettant d’analyser le traumatisme subi par les feuillets de péricardes.La première stratégie visait à déterminer les différences de comportements des péricardes bovins et porcins en matière de diffusion vis à vis de différents solutés. Nous avons pu mettre en évidence que la perméabilité du péricarde porcin était plus élevée (en moyenne 5-fois) et plus hétérogène comparativement à celle du péricarde bovin. La seconde stratégie consistait à caractériser, à l’aide des outils développés, les lésions traumatiques induites lors du déploiement des prothèses auto-expansible ou déployable par inflation d’un ballon. Quelque soit le type de prothèses utilisées, une altération de la perméabilité membranaire des péricardes a été observée après leurs déploiements.La dernière stratégie était de déterminer si le crimping de bioprothèses auto-expansibles pouvait entrainer une calcification plus importante des feuillets péricardiques. Un modèle d’évaluation de la calcification in-vivo chez le lapin a été utilisé. Cette étude à permis d’observer que le taux de calcium ainsi que la minéralisation du péricarde n’étaient pas affectées par le crimping<br>Transcatheter aortic valve replacement (TAVR) is a growing therapy indicated to treat severe aortic valve stenosis. However, an increasing number of studies demonstrated that crimping and deployment of these bioprostheses induce structural alterations of the pericardial leaflets. These observations raise interrogations concerning the long-term durability of these devices.In this thesis works, we developed tools to analyze pericardial leaflets injuries.The first strategy consisted to determine the differences between bovine and porcine pericardium toward the filtration of various solute.It was possible to observe that porcine pericardium hydraulic conductance was higher (5-folds) and more heterogeneous than bovine pericardium.The second strategy consisted to characterize the lesions induced by deployment of self and balloon expandable valved-stents.After deployment, both types of valved-stents showed an alteration of their pericardial hydraulic conductance.The last strategy was to determine if self-expandable valved-stents crimping could increase their pericardial leaflets calcification. The rabbit model was used as an in-vivo evaluation model.This study showed that the calcium concentration and the mineralization of their pericardial leaflets were unaffected by valved-stents crimping
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Pesälä, O. (Otto). "Katetriteitse asetettava läppä (TAVI) iäkkäiden aorttaläppästenoosin hoidossa." University of Oulu, 2016. http://urn.fi/URN:NBN:fi:oulu-201603161321.
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Taustaa: TAVI (transcatheter aortic valve implantation)-toimenpide on perinteistä aorttaläppäleikkausta mini-invasiivisempi operatiivinen vaihtoehto oireisen aorttaläpän stenoosin hoidossa.
Aineisto ja menetelmät: Tutkimme retrospektiivisesti marraskuun 2011 ja syyskuun 2015 välisenä aikana TAVI:lla hoidettujen (n=123) potilaiden päätetapahtumien esiintyvyyttä. Vertailuaineistona toimii ikävakioidut perinteisellä aorttaläppäleikkauksella hoidetut potilaat (n=68).
Tulokset: Sairaalakuolleisuudessa ei todettu eroa TAVI:lla ja AVR:lla hoidettujen potilaiden välillä. Verisuonikomplikaatioita esiintyi merkittävästi enemmän TAVI-ryhmässä ja RIFLE-luokituksen mukaista akuuttia munuaisten vajaatoimintaa kehittyi merkittävästi useammalle AVR-ryhmässä. Komplikaatioita kehittyi vähemmän transfemoraalista reittiä hyödyntäen kuin muilla TAVI-tekniikoilla.
Pohdinta: OYS:ssa TAVI:lla hoidettujen potilaiden hoidon tulokset komplikaatioiden esiintyvyys ovat samaa tasoa kuin kansainvälisissä tutkimuksissa on aiemmin esitetty. Olennaiset hoidon lopputulemat ovat samankaltaiset TAVI:lla ja perinteisen läppäkirurgia välillä.
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DI, LUOZZO MARCO. "Ruolo dell'imaging nel paziente sottoposto a tavi." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2014. http://hdl.handle.net/2108/203221.
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Akodad, Mariama. "Marqueurs pronostiques biologiques et morphologiques du TAVI à l’ère de l’évolution des pratiques." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTT061.
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La prise en charge du rétrécissement aortique a connu une véritable révolution avec l’avènement du remplacement valvulaire aortique percutané (TAVI). Cette technique, s’adressant initialement à des patients à haut risque chirurgical, a été étendue à des patients à moindre risque du fait de l’amélioration des résultats et s’est accompagnée, au fil des années, d’une simplification de la procédure. Cependant, la sélection rigoureuse des patients en amont de la procédure reste la clé du succès de cette technique. Les facteurs cliniques et échographiques sont insuffisants pour permettre une évaluation précise du profil de risque. Certains biomarqueurs et les calcifications de la valve aortique, permettraient d’améliorer la stratification du risque. L’objectif de ce travail était d’évaluer la valeur pronostique de la troponine et du score calcique valvulaire dans le TAVI à l’ère de l’évolution des pratiques. Le premier chapitre de cette thèse a permis de confirmer la valeur pronostique de la troponine en pré et post-procédure TAVI et celle du score calcique avec les valves de la précédente génération. Le deuxième chapitre de ce travail a permis de mettre en évidence l’impact de la prédilatation sur l’élévation de troponine post-procédure avec un rôle pronostique potentiel<br>Management of aortic stenosis was revolutionized by the advent of transcatheter aortic valve replacement (TAVI). This technique, initially targeting patients at high surgical risk, was extended to lower risk patients regarding to improved outcomes and was accompanied, over the years, by a simplification at each step of the procedure. However, the careful selection of patients upstream of the procedure remains the key to success. Clinical and echographic factors are not sufficient to allow an accurate assessment of their risk profile. Thus, biomarkers and aortic valve calcifications evaluation may improve risk profile stratification. The objective of this thesis was to evaluate the prognostic value of troponin and aortic valve calcium score in patients undergoing TAVI in the era of TAVI simplificationThe first chapter of this thesis confirmed the prognostic value of pre- and post-procedure troponin (myocardial injury) in patients undergoing TAVI and of calcium score with previous generation prosthesis.The second chapter highlighted the impact of predilatation on this post-procedure troponin elevation with a potential prognostic impact
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Tzamalis, Panagiotis [Verfasser], and Claus [Akademischer Betreuer] Schmitt. "Prognose des neuaufgetretenen Linksschenkelblockes bei minimalinvasivem Aortenklappenersatz (TAVI)." Freiburg : Universität, 2015. http://d-nb.info/1119246563/34.
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Ramadan, Hassan Jamil [Verfasser], and Ulrich [Akademischer Betreuer] Schäfer. "Notfall-TAVI : Machbarkeit-/und Effektivitätsanalyse einer Notfall-Transkatheter Aortenklappenimplantation (TAVI) bei Patienten mit lebensbedrohlich dekompensierter Aortenklappenstenose / Hassan Jamil Ramadan ; Betreuer: Ulrich Schäfer." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1155725336/34.
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Leung, Wing-ki Vikki, and 梁頴琪. "The implications of transcatheter aortic valve implantation (TAVI) adoption." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48424031.
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Aortic stenosis is a life-threatening valvular heart disease. At the onset of symptoms, a patient’s prognosis becomes poor and the risk of death rapidly increases. Aortic valve replacement surgery remains the gold standard in treatment for aortic stenosis. However, in the total population of patients with severe aortic stenosis, about one third are deemed inoperable due to their high surgical risk. In recent years, the development of transcatheter aortic valve implantation (TAVI), a non-invasive heart valve replacement procedure brought hope for the elderly, high-risk and inoperable aortic stenosis patient population pool. A literature review was performed to examine the safety, efficacy and effectiveness evidence for transcatheter aortic valve treatment option. The results showed that TAVI is a safe treatment option, however the effectiveness for the whole patient population is unknown. The adoption of this alternative treatment option is certainly coupled with multiple dimension of impact from a public health perspective. It remains inconclusive whether TAVI is an effective treatment option to be adopted.<br>published_or_final_version<br>Public Health<br>Master<br>Master of Public Health
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Mormon, Daniel [Verfasser]. "Einfluss von TAVI auf Performanceparameter des rechten Herzens / Daniel Mormon." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2021. http://d-nb.info/1234984008/34.
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Neves, Carolina Moreto. "Aterosclerose da aorta torácica e risco de complicações após TAVI." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16578.
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Mestrado em Tecnologias da Imagem Médica<br>Introdução: A implantação de válvula aórtica percutânea (IVAP) tornou-se uma alternativa terapêutica de sucesso em doentes com estenose aórtica grave sintomática, considerados inoperáveis ou de risco cirúrgico proibitivo. Lesão renal aguda e eventos neurológicos são complicações frequentes após o mesmo, e admite-se que possam estar envolvidos fenómenos de ateroembolismo com origem na aorta torácica.
O objetivo do presente estudo foi investigar a existência de uma associação entre a carga aterosclerótica, avaliada por TCMD, e a ocorrência de LRA e eventos neurológicos após IVAP.
Métodos: Foram selecionados 215 pacientes (idade média 79.0±8.43; 47.9% sexo masculino) que realizaram o procedimento por via transfemoral, com exame de TCMD no sistema. A aorta torácica foi anatomicamente dividida em aorta ascendente, arco aórtico, e aorta descendente, sendo esta última subdividida entre 5 a 8 segmentos de acordo com as artérias intercostais. Os segmentos com uma espessura da íntima ≥ 2mm foram classificados como envolvidos por aterosclerose. A carga aterosclerótica foi determinada com base na proporção de segmentos da aorta torácica afetados, assim como a espessura máxima das placas de ateroma. Os índices de aterosclerose avaliados por TCMD foram correlacionados com a ocorrência de LRA e AVC/AIT utilizando um modelo de regressão logística multivariada.
Resultados: Verificaram-se 51 (23.7%) casos de LRA e 17 (7.9%) eventos neurológicos. O modelo de regressão logística multivariada demostrou uma aparente relação entre a espessura máxima de placa na AoD e LRA, mas nenhuma associação entre carga aterosclerótica e eventos neurológicos.
Conclusão: A ocorrência de LRA aparenta estar associada à presença de aterosclerose na AoD. Não foi possível retirar conclusões relativas a eventos neurológicos.<br>Background: Transcatheter Aortic Valve Implantation (TAVI) has become a successful alternative therapy in patients with symptomatic severe aortic stenosis deemed inoperable or with prohibitive surgical risk. Acute kidney injury and neurological events are frequent complications after the procedure, and it is assumed that may be involved atheroembolism phenomena originating in the thoracic aorta.
The aim of this study was to investigate the possibility of an association between atherosclerotic burden, assessed by MDCT, and the occurrence of AKI and neurological events after TAVI.
Methods: We selected 215 patients (mean age 79.0 ± 8.43; 47.9% male) who underwent a transfemoral approach of the procedure, with MDCT examination in the system. The thoracic aorta was anatomically divided into the ascending aorta, aortic arch and descending aorta, the latter being subdivided into 5 to 8 segments according to the intercostal arteries. The segments with a intimal thickness ≥ 2mm were classified as involved in atherosclerosis. The atherosclerotic load is determined based on the proportion of segments of thoracic aorta affected, as well as the maximum thickness of the atheromatous plaques. Atherosclerotic indices evaluated by MDCT were correlated with the occurrence of AKI and stroke / TIA using a multivariate logistic regression model.
Results: We found 51 (23.7%) cases of AKI and 17 (7.9%) neurological events. The multivariate logistic regression model demonstrated an apparent relationship between the maximum thickness plate in the descending aorta and AKI, but no association between atherosclerotic burden and neurological events.
Conclusions: The presence of AKI appears to be associated with the presence of atherosclerosis in the descending aorta. It was not possible to draw conclusions on the neurological events.
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Görtz, Viola [Verfasser]. "Prospektive Langzeituntersuchung der kognitiven Funktion nach transvaskulärer Aortenklappenimplantation (TAVI) / Viola Görtz." Bonn : Universitäts- und Landesbibliothek Bonn, 2020. http://d-nb.info/121830183X/34.
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Lundström, Sonja Kristina Elisabeth. "Livskvalitet med Perkutan aortaklaff." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176678.
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Le, Ven Florent. "Impact pronostique du débit cardiaque dans la sténose valvulaire aortique." Thesis, Brest, 2016. http://www.theses.fr/2016BRES0116/document.
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La sténose aortique (SA) est la maladie valvulaire cardiaque ayant la plus forte prévalence dans les pays occidentaux. On s’aperçoit que, malgré le respect des recommandations pour les indications opératoires, les patients présentent des évolutions très variables après chirurgie : certains patients restent symptomatiques, décèdent précocement, ou présentent une dysfonction ventriculaire gauche persistante. Il a été montré que les patients présentant à la fois une SA en bas débit (c’est-à-dire un volume d’éjection bas), une fraction d’éjection ventriculaire gauche (FEVG) altérée et un gradient de pression entre le ventricule et l’aorte abaissé avaient un pronostic péjoratif, avec un risque opératoire majoré lorsqu’ils subissaient un remplacement valvulaire chirurgical. Il a aussi été récemment démontré que, dans le contexte de la SA, un bas débit peut survenir alors que la FEVG est normale. Les objectifs généraux de ce doctorat sont d’étudier l’impact du débit (plus précisément le volume d’éjection ventriculaire gauche) sur le pronostic des patients atteints de SA, ainsi que l’évolution du débit après intervention et les déterminants de son évolution. Les résultats indiquent que le volume d’éjection ventriculaire gauche, que ce soit avant intervention, ou son évolution après TAVI (Transcatheter Aortic Valve Implantation), sont des prédicteurs indépendants puissants de mortalité chez ces patients<br>Aortic stenosis (AS) is the most common valvular heart disease in occidental countries. Despite proper use of the guidelines, some patients can present adverse outcomes after surgery: some of them remain symptomatic, some die prematurely, or suffer from a persistant left ventricular dysfunction. It has been demonstrated that patients presenting an AS with low flow (i.e. low stroke volume), impaired left ventricular ejection fraction (LVEF), and a low transvalvular mean gradient, have poor prognosis, with increased risk during aortic valve replacement surgery. It has also been demonstrated that, in AS, a low flow can occur despite a preserved LVEF. The main goals of this PhD were to evaluate the impact of flow (more precisely left ventricular stroke volume) on the prognosis of patients with AS, the evolution of flow after intervention, and the factors that influence it. The results show that left ventricular stroke volume, before or after intervention, or its evolution after TAVI (Transcatheter Aortic Valve Implantation), are powerful independant predictors of mortality
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Hauenschild, Lukas [Verfasser]. "Einfluss der systemischen Entzündungsparameter auf Morbidität und Mortalität nach TAVI / Lukas Hauenschild." Ulm : Universität Ulm, 2019. http://d-nb.info/1191833097/34.
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Vy, Phuoc. "Simulation numérique personnalisée du positionnement des guides dans les procédures d'implantation de valve aortique percutanée." Thesis, Lyon, 2018. https://tel.archives-ouvertes.fr/tel-02921452.
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Cette thèse s’intéresse à l’implantation de prothèse de valve aortique par voie endovasculaire (TAVI). Cette technique mini-invasive bénéficie d’un intérêt croissant depuis son invention il y a environ deux décennies. Elle consiste à conduire une prothèse compressible dans les artères du patient par le biais d’un système de largage composé d’un guide rigide et d’un cathéter de pose. Le bon fonctionnement de la prothèse dépend entre autres de sa position et de son orientation correctes au sein de la racine aortique du patient. Ainsi, la prédiction de la configuration spatiale de la prothèse constitue une aide pertinente pour armer les médecins lors de leur planification pré-opératoire. Dans l’hypothèse que les interactions mécaniques entre le système de largage et les tissus biologiques déterminent la configuration spatiale de la prothèse, la thèse aborde la simulation numérique de la déformation du guide rigide à son insertion.Un modèle mécanique a été mis au point et traduit en modèle numérique résolu par la méthode des éléments finis. La configuration spatiale au niveau de la valve aortique du guide rigide simulé a ensuite été validée avec les données per-opératoires de deux patients. Une vérification globale du modèle a également été réalisée à l’aide d’un fantôme physique imprimé en 3D basé sur la géométrie d’un patient. Enfin, le modèle numérique est exploité pour éclairer le choix d’un guide rigide personnalisé à un cas de patient réel<br>This work revolves around transcatheter aortic valve implantation (TAVI), which delivers a collapsible prosthesis to the native aortic valve through a delivery system (stiff guidewire and prosthesis sheath) inserted in an artery. This procedure became very popular ever since its introduction two decades ago. However, the performance of the treatment is correlated with the positioning of the prosthesis within the aortic root of the patient. Therefore, prediction of the spatial configuration of the prosthesis appears relevant data to assist pre-operative planning. It is assumed that the mechanical interactions between the delivery system and biological tissues determine the spatial configuration of the prosthesis. The thesis explores numerical simulation as a predictive tool. More specifically, the thesis attempts to numerically reproduce the deformations of the inserted stiff guidewire.A mechanical model was developed and translated into a Finite-Element model. The numerical prediction of the guidewire positioning within the aortic valve was validated with intra-operative data from two patient cases. The numerical model was also verified through an experiment using a 3D-printed patient-specific phantom. It was then exploited to choose a guidewire specifically suited for a patient
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Cischek, Silvia [Verfasser], and Julinda [Akademischer Betreuer] Mehilli. "Die Aortenklappenprotheseninsuffizienz nach TAVI beeinflusst die Langzeitmortalität altersabhängig / Silvia Cischek ; Betreuer: Julinda Mehilli." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1228270694/34.
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Niemann, Philip Maximilian [Verfasser]. "Paravalvuläre Lecks nach Transkatheter-Aortenklappenimplantation (TAVI) – Möglicher Nutzen einer Nachdilatation / Philip Maximilian Niemann." Kiel : Universitätsbibliothek Kiel, 2018. http://d-nb.info/115476561X/34.
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Abdul-Jawad, Altisent Omar. "Caracterización del daño neurológico asociado a la TAVI y estrategias terapéuticas para su prevención." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/456574.
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Actualmente la implantación de prótesis aórtica transcatéter (TAVI) representa la principal opción terapéutica para pacientes con estenosis aórtica severa y alto riesgo quirúrgico. La ampliación de las indicaciones TAVI a una población de menor riesgo está limitada por la relativa alta incidencia de eventos cerebrovasculares. El daño neurológico relacionado con la TAVI se ha clasificado en distintos niveles: clínico (ictus y accidente cerebral transitorio); subclínico (infartos silentes detectados por resonancia magnética con ponderación de difusión [DWI]); y cognitivo. Estudios con DWI realizados en pacientes con un perfil de riesgo elevado han mostrado una alta incidencia de daño cerebral subclínico tras la TAVI. No obstante, la repercusión clínica en forma de variaciones del estado cognitivo ha mostrado resultados poco concluyentes. Tampoco conocemos el riesgo de daño subclínico ni las consecuencias cognitivas en una población TAVI con un perfil de riesgo menor.
Existen dos principales estrategias para prevenir el daño neurológico asociado a la TAVI: farmacológica (agentes antitrombóticos) y mecánica (dispositivos de protección embólica). Las guías de práctica clínica recomiendan una terapia antiplaquetar (TAP) post-TAVI para reducir el riesgo de ictus. No obstante, no hay datos sobre la eficacia y seguridad de esta recomendación en pacientes que se encuentren en tratamiento concomitante con antagonistas de la vitamina K (AVK) por fibrilación auricular (FA).
El primer objetivo (estudio 1) fue comparar el grado de daño neurológico subclínico (mediante DWI) y las variaciones del estado cognitivo entre la TAVI y el recambio valvular aórtico quirúrgico (RVA) en una población considerada de riesgo quirúrgico intermedio. El segundo objetivo fue examinar el riesgo de eventos isquémicos y hemorrágicos asociados a dos estrategias antitrombóticas distintas en pacientes con FA sometidos a TAVI.
Los dos estudios presentados son observacionales. El estudio 1 se realizó en el Hospital Vall Hebron. Cuarenta y seis pacientes sometidos a TAVI (78,8±8.3 años, STS score 4,4±1.7) se compararon con 37 pacientes sometidos a RVA (78,9±6,2 años, STS score 4,7±1,7). La DWI se realizó durante los primeros 15 días tras la intervención y la valoración cognitiva a nivel basal y a los 3 meses tras la intervención. No se observaron diferencias en la incidencia de ictus (2,2% en TAVI vs. 5,4% en RVA, p=0.58), ni en la incidencia de lesiones cerebrales subclínicas detectadas por DWI (45% vs. 40,7%, OR-ajustada 0,95 [0,25-3,65], p=0,94). La edad fue un predictor de nuevas lesiones (p=0,01), y el tratamiento con antagonistas de la vitamina K (AVK) tuvo un efecto protector (p=0,037). No se observaron cambios significativos en las puntuaciones de los test cognitivos tras la intervención.
El estudio 2 incluyó a 621 pacientes con FA sometidos a TAVI. Se compararon dos estrategias antitrombóticas utilizadas en mundo real: monoterapia (MT) con el uso único de AVK (n=101) vs. terapia multi-antitrombótica (MAT) con el uso de TAP más AVK (n=520). Durante un seguimiento medio de 13 meses no se observaron diferencias en la incidencia de ictus (p=0.67), eventos cardiovasculares mayores (combinado de ictus, infarto o muerte cardiaca, p=0.33), o muerte (p=0.76). No obstante sí se documentó un mayor riesgo de hemorragia mayor o amenazante en el grupo MAT (HR 1,85 [1,05-3,28], p=0,04).
El estudio 1 mostró que en una población de riesgo intermedio el daño neurológico tras la TAVI fue similar que tras el RVA. Aunque la incidencia de daño subclínico era elevada (tras la TAVI o RVA) su impacto clínico no pareció relevante. En el estudio 2 se observó que añadir una TAP a pacientes que están en tratamiento con AVK por FA y son sometidos a TAVI no aportó ningún beneficio y en cambio sí aumentó el riesgo de hemorragia.<br>Transcatheter aortic valve implantation (TAVI) is now the principal therapeutic option in patients with severe aortic stenosis deemed at high surgical risk. Implementing TAVI in a lower risk profile population could be limited by relatively high incidence of neurological damage related with the procedure. Neurological damage has been classified at different levels: clinical (stroke or transient ischemic attack), subclinical (silent embolic infarcts after procedure demonstrated by Diffusion Weighted resonance Imaging [DWI]), and cognitive. DWI studies performed in high risk patients have demonstrated the ubiquitous presence of subclinical damage following TAVI. However its effects on cognition showed inconclusive results. To date, the risk of subclinical damage and cognitive fluctuations following TAVI in a population deemed at lower risk is unknown.
There are currently two main strategies to prevent neurological damage related with TAVI: pharmacological (antithrombotic agents) and mechanical (embolic protection devices). Guidelines recommend antiplatelet therapy (APT) post-TAVR to reduce the risk of stroke. However, data on the efficacy and safety of this recommendation in the setting of a concomitant indication for oral anticoagulation (due to atrial fibrillation [AF]) are scare.
The first objective (study 1) was to compare the degree of neurological damage using DWI and cognitive testing between TAVI and surgical aortic valve implantation (SAVR) in patients deemed at intermediate surgical risk. The second objective (study 2) was to examine the risk of ischemic events and bleeding episodes associated with differing antithrombotic strategies in patients undergoing TAVI with concomitant AF.
The two studies presented were observational. Study #1 was conducted in Vall Hebron Hospital. Forty-six patients undergoing TAVI (78.8±8.3 years, STS score 4.4±1.7) and 37 patients undergoing SAVR (78.9±6.2 years, STS score 4.7±1.7) were compared. DWI was performed within the first 15 days post-procedure. A cognitive assessment was performed at baseline and at 3 months follow-up. TAVI and SAVR groups were comparable in terms of baseline characteristics. There were no differences in incidence of stroke (2.2% in TAVR vs. 5.4% in SAVR, p=0.58), neither in the rate of acute ischemic cerebral lesions detected by DWI (45% vs. 40.7%, adjusted OR 0.95 [0.25-3.65], p=0.94). An older age was a predictor of new lesions (p=0.01), and therapy with vitamin K antagonist (VKA) had a protective effect (p=0.037). Overall no significant changes were observed in global cognitive scores post-intervention.
Study #2 was a real world multicenter evaluation comprising 621 patients with AF undergoing TAVI. Two groups were compared: mono-therapy (MT) group (with the use of VKA alone, n=101) vs. multi-antithrombotic (MAT) group (with the use of VKA plus APT, as recommended by guidelines, n=520). During a follow-up of 13 months there were no differences between groups in the rates of stroke (MT 5% vs. MAT 5.2%, HR 1.25 [0.45-3.48], p=0.67), major cardiovascular endpoint (combined of stroke, myocardial infarction or cardiovascular death, p=0.33) or death (p=0.76), however a higher risk of major or life-threatening bleeding was found in the MAT group (HR 1.85 [1.05-3.28], p=0.04).
Study #1 found similar rate of cerebral damage following TAVI and SAVR in patients at intermediate risk. Although acute lesions occurred frequently in both strategies, their cognitive impact was not clinically relevant. Study #2 found that in TAVI recipients prescribed VKA therapy for AF, concomitant APT use appears not to reduce the incidence of stroke, major adverse cardiovascular events, or death, while increasing the risk of major or life-threatening bleeding.
Though only observational, the important lessons to be drawn from this thesis are that under a neurological perspective implementing TAVI in an intermediate risk populations appears reasonable; and that the currently recommendation of prescribing APT for patients with AF who are already on long-term anticoagulation does not confer any benefit while potentially being harmful.
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Clauss, Andrea [Verfasser]. "Einfluss von Antikoagulation auf den Gradienten der Aortenklappenprothese nach transfemoraler Aortenklappenimplantation (TAVI) / Andrea Clauss." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1224232674/34.
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Guedeney, Paul. "Approche multimodale des mécanismes thrombotiques liés aux prothèses cardiaques valvulaires et structurelles." Electronic Thesis or Diss., Sorbonne université, 2024. http://www.theses.fr/2024SORUS004.
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Cette thèse évalue les facteurs de risque et traitements des processus thrombotiques impliquant les prothèses cardiaques valvulaires (TAVI) et structurelles (fermeture de foramen ovale perméable - PFO) aux travers de 6 études. L’étude 1 démontre dans une méta-analyse que l’aspirine en monothérapie est le régime antithrombotique associé au meilleur ratio efficacité/tolérance par rapport à la double thérapie antiplaquettaire (DAPT), recours aux anticoagulants oraux direct (AOD) ou association d’AOD et d’antiagrégant plaquettaire. L’étude 2, autre méta-analyse, rapporte une incidence de thrombose infraclinique de bioprothèse percutanée allant de 1.1% à 16.4% selon le recours respectif à l’échographie ou le scanner cardiaque. Ces thromboses étaient plus fréquentes en l’absence de traitement anticoagulant ou de prothèse intra-annulaire. Dans le domaine de la fermeture du PFO, l’étude 3 a démontré que le recours à la DAPT, actuellement recommandé de façon systématique pour une durée variable, ne semblait pas apporter de bénéfice significatif en termes de prévention de complication ischémique par rapport à la monothérapie antiplaquettaire, remettant en cause les recommandations actuelles. L’étude 4 a consisté en un monitoring rythmologique ≥28 jours post-fermeture et a rapporté une incidence d’arythmie supraventriculaire de 20.9%, particulièrement fréquente chez les hommes, les patients âgés de ≥60ans et en cas de prothèse de grande taille. L’étude 5 n’a pas mis en évidence de différence sur le devenir des patients selon le délai entre le dernier évènement embolique et la fermeture du PFO suggérant que l’intervention pouvait être bénéfique aussi bien en cas d’intervention précoce que tardive. Enfin l’étude 6 a souligné qu’une source potentielle de thrombus veineux pouvait être retrouvée chez 58.5% des patients adressés pour fermeture percutanée de PFO en prévention secondaire d’embolie paradoxale<br>This thesis evaluates the risk factors and treatment of thrombosis involved in cardiac valvular and structural devices such as transcatheter aortic valve implantation (TAVI) and percutaneous closure of patent foramen ovale using 6 studies. Study 1 is a meta-analysis demonstrating that aspirin is the post-TAVI regimen with the best efficacy/safety ratio compared to dual antiplatelet therapy (DAPT), direct oral anticoagulant (DOA), or the association of DOA and antiplatelet. Study 2 is another meta-analysis reporting an incidence of subclinical TAVI leaflet thrombosis varying between 1.1% according to echocardiographic-based evaluation and 16.4% according to computed scan-based studies and was more frequent in case of intra-annular device or lack of anticoagulant therapy. Study 3 did not report any significant gain of systematic transient DAPT following percutaneous closure of PFO compared to SAPT, challenging current recommendations. In study 4, we performed a systematic cardiac monitoring for at least 28 days following PFO closure and reported an incidence of supraventricular arrhythmias of 20.9% overall, which was even more frequent among male patients, patients aged ≥60 years or in case of use of large device. Study 5 did not find any significant difference in term of outcomes according to the delay from last embolic index event and PFO percutaneous closure suggesting that the procedure could beneficial in case of both early and delayed interventions. Finally, study 6 reported that a potential source of venous thrombosis could be present in as much as 58.5% of patients addressed to PFO percutaneous closure in secondary prevention
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Dombrowski, Martin [Verfasser]. "Expression zirkulierender microRNAs bei Patienten mit Aortenklappenstenose vor und nach kathetergestütztem Aortenklappenersatz (TAVI) / Martin Dombrowski." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1173898743/34.
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Schewel, Jury [Verfasser], and Ulrich [Akademischer Betreuer] Schäfer. "Transkatheter Aortenklappenimplantation (TAVI) : Evaluation invasiver Globalparameter und deren prognostische Bedeutung. / Jury Schewel. Betreuer: Ulrich Schäfer." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2014. http://d-nb.info/1060484285/34.
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Stark, Sophia [Verfasser]. "Hoch-sensitives Troponin T in Hochrisiko-Patienten vor und nach Transkatheter-Aortenklappenimplantation (TAVI) / Sophia Stark." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1122110901/34.
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Derman, Esra. "Transapikaler Aortenklappenersatz im Vergleich mit konventioneller Methode." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-84248.
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Der Goldstandard in der Behandlung der hochgradigen Aortenklappenstenose ist der konventionelle Aortenklappenersatz am ruhenden Herzen mittels Thorakotomie und Anschluss an die Herz-Lungen-Maschine. In Anbetracht des demographischen Wandels mit steigender Anzahl alter und multimorbider Patienten wurden Verfahren entwickelt, welche schonender und weniger belastend für die Patienten sein sollen und somit ein geringeres Operationsrisiko bergen. Der transapikale Aortenklappenersatz mittels Mini-Thorakotomie am schlagenden Herzen ist Gegenstand der vorliegenden Arbeit. Die bisherigen Ergebnisse der minimalinvasiven Verfahren bei Hochrisikopatienten sind vielversprechend. Ziel der vorliegenden Arbeit ist zu klären, ob die transapikale mit der konventionellen Methode vergleichbar ist. Die Studie prüft unter anderem das Gesamtüberleben, das postoperative Monitoring, neurologische Ereignisse und ob das präoperativ erhobene Risikoprofil einen Einfluss auf das Gesamtüberleben der Patienten hat. Die Ergebnisse deuten darauf hin, dass die minimalinvasiven Verfahren in Zukunft eine große Rolle spielen werden.
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DELLA, ROSA FRANCESCO. "Impact of asymptomatic carotid stenosis on mid term outcome of transcatheter aortic valve replacement." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2016. http://hdl.handle.net/10281/105574.
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Introduction Stroke is a potential major complication of aortic valve replacement (AVR), transcatheter aortic valve implantation (TAVI), and balloon aortic valvuloplasty (BAV). Although its occurrence is rare, stroke significantly affects survival and quality of life. Peripheral vascular disease and carotid artery disease are independent risk factors that have been identified as predictors of operative death according to surgical risk scores. The presence of a significant carotid stenosis may increase the surgical risk leading to the choice of a percutaneous transaortic valve implantation rather than a surgical AVR.
At present there is no evidence that describes the impact of asymptomatic significant carotid stenosis detected accidentally during preoperative evaluation on the onset of cerebrovascular periprocedural events after TAVI.
Population In this first analysis we considered 521 patients with severe aortic stenosis (AS) and cardiac symptoms (New York Heart Association [NYHA] class II function or worse). A score of at least 20 % on the EuroSCORE (European System for Cardiac Operative Risk Evaluation) and 10% on the risk model developed by the Society for Thoracic Surgeons (STS).,
Follow-up All patients underwent clinical surveillance, bio-chemical tests, electrocardiogram and echocardiogram before hospital discharge. The follow-up assessment included medical examination, electrocardiogram and echocardiogram to perform valve imaging and hemodynamic evaluation. It was performed at our Center or at the treating cardiologist ambulatory 30 days and one year after the procedure.
The events considered were mortality (by all-cause and cardiovascular death), myocardial infarction, stroke and transient ischemic attack (TIA), bleeding (minor and life-threatening bleeding), acute renal failure, vascular complications, disturb of conduction and arrhythmias and the combined criteria of safety, according to VARC and VARC 2 definitions.
Procedure The coexistence of carotid and peripheral artery diseases not only further increases risk and long-term mortality but influences also technical approaches since all centers adopt a policy of using the transfemoral approach first, with criteria for the use of non-transfemoral approaches that are based on the size and degree of tortuosity, calcifications, and atheroma of the aorto-iliofemoral arterial tree, as assessed by the multidisciplinary team.
In our Center, preventive measures have been taken to limit the risk associated to the procedure in our patients presenting carotid artery stenosis.
Results The main findings of the current study are the following: (a) no correlation has been observed about the presence of an asymptomatic carotid artery stenosis discovered before the TAVI procedure and mortality, rate of cerebrovascular events (stroke or TIA) and myocardial infarction during the first postoperative month; (b) no differences concerning all-causes and cardiovascular mortality and onset of cerebrovascular events (stroke/TIA) at long-term have been shown between patients with and without CAS.
Conclusion The presence of asymptomatic carotid stenosis is not a risk factor for cerebrovascular events after percutaneous aortic valve implantation at 30 days and one-year follow-up. Cerebrovascular events after TAVI occur in a vulnerability period extending to 1 month post-procedure. No difference exists in the CVE rate with regard to the type of valve or the access route.
Coronary, carotid, aortic, iliac and femoral artery disease are often found in elderly patients presenting with severe symptomatic AS undergoing TAVI. These patients are also affected by several clinical factors and frailty that correlate with the presence and severity of arterial pathologies and can impact on incidence of CVEs and longterm survival
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Facchin, Michela. "Clinical and Hemodynamic Results after Transcatheter Aortic Valve implantation (TAVI): Early and Late (10-year) follow-up." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3424733.
Full textAbstract:
Transcatheter aortic valve implantation (TAVI) has become the treatment of choice in patients with severe symptomatic aortic stenosis (AS) considered inoperable or at high surgical risk. More recently, TAVI has been performed also to lower risk patients based on the Heart Team decision. Few studies have studied interaction between surgical risk categories and outcomes.
Aim of the study
To analyze safety and efficacy (VARC-2 defined) TAVI treated patients as function of different preoperative risk. To assess independent predictors of death.
Methods
Four-hundred-eighty-two patients who underwent TAVI in our center between 2007 and 2017 were included in the study. According to Society of Thoracic Surgeons (STS) score and to other parameters, all the patients were retrospectively stratified into 4 groups: prohibitive (contraindications to aortic valve replacement, n = 124), high (STS > 8, n = 131), intermediate (4 ≤ STS ≤ 8, n = 112) and low (STS < 4, n = 115) risk. Early, 1-year and long-term outcomes have been evaluated in those 4 groups according the VARC 2 criteria.
Results
The TAVI procedure resulted to be safe because of low mortality rate throughout all risk groups. The lowest 30-days mortality rate was observed in low and prohibitive-risk patients (p=0.048). In the low risk group, in-hospital mortality was 0%. The results were similar at 1-year of follow-up, with a mortality rate of 6% and 7% in low- and prohibitive-risk patients vs 21% and 19% in intermediate- and high-risk groups, (p<0.008). At 5-year of follow-up the mortality rate was 52% and it appeared to be lower only in low-risk patients at long-term follow-up. Independent predictors of mortality were pre-procedural congestive heart failure (CHF), neoplastic disease, pre-procedural-creatinine, post-procedural major or life threatening bleeding and post-procedural acute kidney injury (AKI). Implanted prosthesis performed well with stable hemodynamic results over time and rare dysfunction (2.1%).
Conclusions
In our study population, TAVI was safe and effective, with low rates of mortality and adverse events regardless of the surgical risk. At longer follow-up mortality rate was significantly lower in low-risk patients. Pre-procedural CHF, neoplastic diseases, pre-procedural creatinine, post-procedural severe bleedings and post-procedural AKI were independent predictors of mortality. Transcatheter heart valves (THV) performance after the procedure was excellent and stable over time with low rate of late prosthesis dysfunction. Further studies should be addressed to confirm the promising long-term results among low-risk patients and the long-term durability of THV.
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Chiorean, Mihai [Verfasser]. "Bedeutung von Parametern der Gebrechlichkeit für die Ein-Jahres-Mortalität nach kathetergestützter Aortenklappenkorrektur (TAVI) / Mihai Chiorean." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2021. http://d-nb.info/1241539952/34.
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Morgott, Philipp [Verfasser], and Christian [Akademischer Betreuer] Thilo. "Festlegung der Implantationsebene vor TAVI: Einfluss auf Eingriffsdauer, Strahlenbelastung und Kontrastmittelverbrauch / Philipp Morgott ; Betreuer: Christian Thilo." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/124196372X/34.
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Shirzadi, Mohammad Mehdi. "Development of a patient-specific finite element model of the transcatheter aortic valve implantation (TAVI) procedure." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/22893.
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Transcatheter Aortic Valve Implantation (TAVI) is a procedure developed for replacing the defective aortic valve of a patient as an alternative to open heart Surgical Aortic Valve Replacement (SAVR). In the TAVI procedure a prosthetic valve, which is assembled on to a stent, is crimped and delivered to the patient's aortic root site through several available percutaneous means. The percutaneous nature of TAVI, which is its core advantage in comparison to other SAVR procedures, can however also be its main disadvantage. This is due to lack of direct access to the calcified leaflets, and hence reliance on the host tissue for the proper positioning and anchorage of the deployed prosthetic valve. Therefore, it is desired to have a preoperative quantitative understanding of patient-specific biomechanical interaction of the stent and the native valve to be able to maximise the chance of success of the procedure. The aim of this study was to develop a patient-specific Finite Element (FE) model of the Transcatheter Aortic Valve Implantation (TAVI) procedure for two patients, using a model of the 23 mm percutaneous prosthetic aortic valve developed by Strait Access Technologies (SAT), for the purpose of its post-operative performance. In this regard, the image processing software ScanIP was used to extract the 3D models of the patient-specific aortic roots and leaflets from the provided Multi-Slice Computer Tomography (MSCT) images of the patients. An anisotropic hyperelastic material model was implemented for the roots and leaflets, using two and one families of collagen fibres for their tissues respectively. The stent is made of a cobalt-chromium alloy and its mechanical response was modelled as an isotropic elastoplastic material, with a linear elastic initial response, followed by plastic behaviour with isotropic hardening. The prosthetic leaflets are made of polymer and were modelled as an isotropic hyperelastic material, using the provided experimental test data. The results for the first patient showed that the stent maintained its structural integrity after deployment, and successfully pushed the native leaflets back to keep the aortic root clear of all impediments. No obstruction of the coronary ostia was observed, and prosthetic leaflets were seen to function normally. The stent radial recoil was calculated to be between 2 to 4.28 % after deployments. Its foreshortening was calculated to be approximately 20%. The stent was observed to move back and forth by approximately 3 mm in the last simulation step in which cardiac cycle pressure were applied to the aortic root and prosthetic leaflets. Also, two openings were observed between the stent and aortic root wall during this simulation step, which indicates the possibility of paravalvular leakage. From the second patient simulation, it was observed that the 23 mm stent was not a good choice for this patient, and will cause severe damage or tissue tearing. The maximum principal stress in the aortic root and valve tissues were observed to follow approximately the defined collagen fibre directions.
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Schneider, Stephan [Verfasser], and Christian [Akademischer Betreuer] Thilo. "Transcatheter Aortic Valve Implantation (TAVI) - Durchführung des minimalistischen Ansatzes ("The minimalist approach") / Stephan Schneider ; Betreuer: Christian Thilo." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1229350306/34.
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Zubrod, Ann-Katrin [Verfasser], Frank [Gutachter] Weidemann, and Christian [Gutachter] Ritter. "Etablierung des kathetergestützten Aortenklappenersatzverfahrens (TAVI) an der Universitätsklinik Würzburg / Ann-Katrin Zubrod. Gutachter: Frank Weidemann ; Christian Ritter." Würzburg : Universität Würzburg, 2015. http://d-nb.info/1110984960/34.
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von, Ingersleben Nora [Verfasser]. "Minimal invasiver Aortenklappenersatz (TAVI) bei degenerativer kalzifizierender Aortenklappenstenose – Risikostratifizierung anhand des neuen Biomarkers Osteopontin / Nora von Ingersleben." Kiel : Universitätsbibliothek Kiel, 2018. http://d-nb.info/1151880671/34.
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Tuladhar, Sugat Ratna. "Development and characterisation of bioengineered percutaneous heart valves using xenogeneic decellularised pericardia." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3424734.
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Heart valve disease (HVD) represents a major health problem, causing significant morbidity and mortality worldwide. The gold standard for treating HVD is surgical replacement of the diseased valve with a prosthetic one. However, many patients affected by HVD cannot receive surgical treatment due to their old age or multiple comorbidities, such as poor left ventricular function, coronary artery disease, kidney failure or chronic lung diseases. The alternative solution for these patients is transcatheter implantation of a valve prosthesis, i.e. a percutaneous heart valve (PHV), by minimally invasive techniques. Current heart valve prostheses for this approach are composed of chemically treated xenogeneic tissue. As such, a limitation common to all of them is the inability of remodelling, repair, and regeneration, which are particularly problematic in case of paediatric patients.
Decellularised scaffolds presenting a natural histoarchitecture have been shown to be a good alternative to chemically processed xenograft. Decellularisation is a process, which removes cells and other xenogeneic components from the treated tissue while retaining the integrity of its extracellular matrix components, which are essential for supporting cell engraftment and function. Importantly, decellularisation has the potential to remove immunogenic factors rendering decellularised xenografts potentially biocompatible in an in-human implantation.
In this project, decellularised pericardium has been applied with the aim to develop bioengineered percutaneous heart valves (bioPHVs) with possibly superior potential of long-term performance in comparison to conventional cardiac valve prostheses.
Porcine and bovine pericardia were decellularised using an established protocol combining Triton X-100, sodium cholate and endonucleases. Decellularisation was verified through histology, immunofluorescence, and biochemistry. BioPHVs were fabricated by sewing the decellularised pericardia onto commercially available stents. The bioPHVs were as first evaluated by hydrodynamic performance according to ISO 5840-3 standard requirements. Second, the possible effects of valve crimping on bioPHV decellularised pericardial tissues were assessed through histological and morphometrical analysis.
Histology, immunofluorescence, and biochemical analyses revealed TRICOL to be equally successful for the decellularisation of both porcine and bovine pericardia. Hydrodynamic tests showed that bioPHVs satisfied the minimum performance requirements indicated by ISO 5840-3. The hydrodynamic behaviour of the bioPHVs was comparable, or even superior, to the one exhibited by the control valves. BioPHVs were also able to withstand extreme back pressure conditions without any severe regurgitations. Examination, both macroscopic and microscopic, of the valve samples after crimping showed no major trauma or injury on the pericardial cusps.
This study demonstrated the suitability of the decellularised pericardium, either bovine or porcine, as an alternative to the glutaraldehyde-treated equivalent. Among the two types of pericardial species tested, preliminary results indicated that the porcine tissue would be preferable to fabricate advanced PHV replacements.<br>La malattia della valvola cardiaca (HVD) rappresenta un grave problema di salute, causando una significativa morbilità e mortalità in tutto il mondo. Il gold standard per il trattamento di HVD è la sostituzione chirurgica della valvola malata con una protesica. Tuttavia, molti pazienti affetti da HVD non possono ricevere un trattamento chirurgico a causa della loro vecchiaia o multiple comorbidità, come scarsa funzione ventricolare sinistra, malattia coronarica, insufficienza renale o malattie polmonari croniche. La soluzione alternativa per questi pazienti è l'impianto transcatetere di una protesi valvolare, cioè una valvola cardiaca percutanea (PHV), con tecniche minimamente invasive. Le attuali protesi valvolari cardiache per questo approccio sono composte da tessuto xenogenico trattato chimicamente. Come tale, una limitazione comune a tutti loro è l'incapacità di rimodellamento, riparazione e rigenerazione, che sono particolarmente problematici nel caso di pazienti pediatrici.
Gli scaffold decellularizzati che presentano un'istologia architettonica naturale hanno dimostrato di essere una buona alternativa allo xenoinnesto trattato chimicamente. La decellularizzazione è un processo che rimuove le cellule e altri componenti xenogenici dal tessuto trattato, mantenendo l'integrità dei componenti della matrice extracellulare, essenziali per supportare l'attecchimento e la funzione delle cellule. È importante sottolineare che la decellularizzazione ha il potenziale per rimuovere i fattori immunogenici rendendo xenotrapianti decellularizzati potenzialmente biocompatibili in un impianto in-umano.
In questo progetto, il pericardio decellularizzato è stato applicato con lo scopo di sviluppare valvole cardiache percutanee bioingegnerizzate (bioPHV) con possibilmente un potenziale superiore di prestazioni a lungo termine rispetto alle protesi valvolari cardiache convenzionali.
La pericardia suina e bovina è stata decellularizzata usando un protocollo stabilito che combina Triton X-100, sodio colato e endonucleasi. La decellularizzazione è stata verificata attraverso l'istologia, l'immunofluorescenza e la biochimica. I BioPHV sono stati fabbricati cucendo la pericardia decellularizzata su stent disponibili in commercio. I bioPHV sono stati valutati per la prima volta dalle prestazioni idrodinamiche secondo i requisiti dello standard ISO 5840-3. In secondo luogo, i possibili effetti della crimpatura della valvola sui tessuti pericardici decellularizzati di bioPHV sono stati valutati mediante analisi istologica e morfometrica.
Istologia, immunofluorescenza e analisi biochimiche hanno rivelato che TRICOL ha ugualmente successo per la decellularizzazione della pericardia suina e bovina. I test idrodinamici hanno dimostrato che i bioPHV soddisfacevano i requisiti minimi di prestazione indicati dalla norma ISO 5840-3. Il comportamento idrodinamico dei bioPHV era comparabile, o addirittura superiore, a quello mostrato dalle valvole di controllo. I BioPHV erano anche in grado di resistere a condizioni estreme di contropressione senza rigurgiti gravi. L'esame, sia macroscopico che microscopico, dei campioni delle valvole dopo la crimpatura non ha mostrato traumi o traumi maggiori alle cuspidi pericardiche.
Questo studio ha dimostrato l'idoneità del pericardio decellularizzato, sia bovino che porcino, in alternativa all'equivalente trattato con glutaraldeide. Tra i due tipi di specie pericardiche testate, i risultati preliminari hanno indicato che il tessuto suino sarebbe stato preferibile per fabbricare sostituzioni avanzate di PHV.
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Alektorov, Kirill [Verfasser]. "Diagnostischer Stellenwert der CT-Koronarangiographie im Rahmen der kardialen Volumen-CT vor geplanter kathetergestützter Aortenklappenimplantation (TAVI) / Kirill Alektorov." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2019. http://d-nb.info/1202044336/34.
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Harb, Bassam Antonios [Verfasser]. "Quantifizierung der Aorteninsuffizienz nach Transkatheter Aortenklappenimplantation (TAVI) anhand invasiver hämodynamischer Parameter und deren therapeutische Konsequenz / Bassam Antonios Harb." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2014. http://d-nb.info/1047579278/34.
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Stanova, Viktoria. "Calcul des contraintes exercées sur les feuillets de bioprothèses aortiques : incidence sur la durabilité de ces dispositifs médicaux." Thesis, Aix-Marseille, 2020. http://www.theses.fr/2020AIXM0112.
Full textAbstract:
Les maladies valvulaires sont parmi les maladies cardiovasculaires les plus fréquentes. Il n’existe actuellement aucun traitement pharmacologique pour prévenir ni ralentir ces maladies et la seule option thérapeutique actuelle est le remplacement valvulaire. Ce dernier peut être effectué soit de manière chirurgicale (RVAC) soit de manière percutanée (TAVI). Le RVAC est le traitement de référence depuis 60 ans.Cependant, au cours de la dernière décennie, le TAVI est devenue un traitement de référence pour les patients à haut risque chirurgical et une alternative pour les patients à risque intermédiaire. Malgré les résultats favorables, la durabilité limitée en raison de la dégénérescence structurelle reste la principale limitation de ces bioprothèses. Quantifier la contrainte mécanique répétitive imposée aux feuillets des bioprothèses, est donc un défi capital et urgent, afin d’optimiser la durabilité de ces dispositifs médicaux.L’absence de données cliniques rétrospectives sur la durabilité à long terme des nouvelles générations de bioprothèses encourage l’utilisation des simulations numériques qui deviennent une partie intégrante de leur évaluation. L’objectif de ce travail est de mettre au point une méthode basée sur l’association d’expériences in vitro/in silico. Elle a été développée afin d’estimer les contraintes appliquées sur les feuillets des bioprothèses aortiques en utilisant un système optique par stéréophotogrammétrie et la corrélation d'images. Les déplacements obtenus in vitro ont ensuite été implémentés dans un modèle d'éléments finis afin de calculer les contraintes mécaniques. Des zones privilégiées de contraintes maximales ont ainsi pu être déterminées<br>Heart valve diseases are the most prevalent form of cardiovascular disease. Currently, no medical therapy is available for successfully treating calcific aortic stenosis and the only option is the valve replacement, either conventional surgical (SAVR) or transcatheter aortic valve implantation (TAVI). Surgical valve replacement has been the standard of care for the past 60 years. However, in the past decade, transcatheter aortic valve implantation has become a viable alternative to surgical aortic valve replacement in patients with high or intermediate surgical risk. Despite the favorable results, the main limitation of both, surgical and TAVI bioprostheses, is their limited durability due to structural valve degeneration (SVD). Quantifying the mechanical fatigue in the form of repetitive stresses imposed to the valve leaflets of aortic bioprostheses is therefore a major and urgent challenge in order to optimize their durability. The lack of long-term durability data for new generations of surgical and percutaneous bioprostheses encourages the use of numerical simulations, representing a significant resource to evaluate and improve these devices. The objective of this thesis is to develop an in vitro/in silico method that offers an experimental evaluation of the mechanical stress applied on bioprosthetic leaflets using a non-contact system based on stereophotogammetry and digital image correlation (DIC). The deformation obtained from the DIC analysis was applied in the finite element model which allows a realistic opening and closing of each leaflet, in order to calculate the local mechanical stress applied. High stress regions could thus be identified and quantified
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Falcão, Gil. "Substituição percutânea da válvula aórtica (TAVI) em doentes com estenose aórtica: revisão bibliográfica e análise da casuística do CHVNG." Master's thesis, Universidade da Beira Interior, 2011. http://hdl.handle.net/10400.6/1176.
Full textAbstract:
Introdução: A estenose valvular aórtica (EA) representa uma redução da área de abertura sistólica da válvula aórtica, sendo a EA degenerativa relacionada com a idade, a etiologia mais comum em adultos. Este trabalho pretende estudar o capítulo da EA, nomeadamente o seu novo tratamento – Substituição percutânea da válvula aórtica (TAVI). A implantação da válvula aórtica por via percutânea é um procedimento emergente no tratamento dos doentes com EA severa, sendo uma possível alternativa ao tratamento cirúrgico. A evolução da técnica e dos materiais tem simplificado e generalizado a sua utilização.
Métodos: Para elaborar a revisão bibliográfica, procedeu-se a uma análise e compilação de informação actualmente existente. Relativamente à análise da casuística do Centro Hospitalar de Vila Nova de Gaia (C.H.V.N.G), para determinar o número de casos de EA tratados com a TAVI, procedeu-se à análise retrospectiva dos processos clínicos. Os dados recolhidos são referentes aos pacientes submetidos a este tipo de intervenção nas datas compreendidas entre 30 de Agosto de 2007 a 28 de Fevereiro de 2011. A selecção dos pacientes incluídos neste tratamento implicou alguns factores como: doente com EA grave (área <0,7cm²/ m²) sintomáticos e recusados para cirurgia de substituição valvular. Foi utilizado em todos eles o dispositivo CoreValve, uma prótese auto-expansível de pericárdio porcino, montada numa estrutura de nitinol e entregue num cateter.
Resultados: Ecocardiograficamente, a maioria dos pacientes apresentaram gradientes médio e máximo de pressão Ventrículo Esquerdo - Aorta (VE-Ao) aumentados (53,2±12,7 mmHg e 88,8± 19,2 mmHg, respectivamente) e área média da válvula aórtica (AVA) diminuída (0,52±0,10 cm²). 59% apresentaram Insuficiência Mitral (IM) grau ≤ I e 41% grau II. Mais de 50% tinha Insuficiência Aórtica (IA) ≤I e 3% tinha uma IA de grau III. Vinte e sete apresentaram Hipertensão pulmonar (HTP) (designada por uma PSAP> 40mmHg). Após a TAVI, a AVA média aumentou para 1,63±0,23 cm² e os gradientes médio e máximo diminuíram para 18,5±4,5 mmHg e 21,36±10,1 mmHg, respectivamente. Dos 59 pacientes seguidos, 14 já faleceram, 42 permanecem vivos e os 3 restantes deixaram de ter qualquer contacto com o Hospital.
Conclusão: Verificou-se que a aplicação da TAVI é maior no sexo feminino, sendo no entanto desejável a todos os pacientes com comorbilidades e factores que os impedem de seguir a via de tratamento comum – substituição cirúrgica da válvula aórtica (AVR). Pode ser então uma técnica eficaz na melhoria da qualidade de vida dos doentes com EA, sendo uma potencial alternativa válida em doentes com EA severa sintomática.<br>Introduction: The aortic valve stenosis (AS) represents a decreasing of the aortic valve´s
systolic opening area, being the age related degenerative AS the most common etiology in
adults. This bibliographical revision aims to study the AS chapter, namely its new way of
treatment – Transcatheter Aortic Valve Implantation (TAVI). The percutaneous aortic valve
implantation is an emerging procedure in the healing of patients with severe AS, being a
possible alternative to surgical treatment. The whole technique and materials development has
simplified and generalized its use.
Methods: In order to prepare the bibliographical revision, an analysis was done and a
compilation from the currently available data as well. For the analysis of the sample of Centro
Hospitalar de Vila Nova de Gaia (C.H.V.N.G), it was done the retrospective analysis of the
clinical processes so as to determine the number of the EA cases treated with TAVI. The data
collected refer to the patients undergoing this type of intervention, from August 31st 2007 to
February 28th 2011. The selection of patients included in this treatment involved several factors
such as: symptomatic patients with severe AS (area <0,7cm²/ m²) who were refused to surgical
valve replacement. A device called CoreValve was used in all of them, consisting of a porcine
pericardium self-expandable prosthesis, applied on a nitinol frame and delivered in a catheter.
Results: Through the ecocardiography, most of the patients had an increased mean and
maximum Left Ventricle – Aorta pressure gradients (VE-Ao) (53,2±12,7 mmHg e 88,8± 19,2
mmHg, respectively) and a decreased average area of the aortic valve (AVA) (0,52±0,10 cm²).
59% had grade ≤ I mitral regurgitation (MI) and 41% grade II MI. More than a half had grade ≤I
aortic regurgitation (AI) and 3% had a grade III AI. Twenty seven patients had pulmonar
hypertension (HTP) (represented by a PSAP (Pulmonary artery systolic pressure) >40mmHg).
After the TAVI procedure, the AVA increased to 1,63±0,23 cm² and the mean and maximum
transvalvular gradients decreased to 18,5±4,5 mmHg e 21,36±10,1 mmHg, respectively. From
the 59 treated patients, 14 have already died, 42 are still alive and the remaining 3 no longer
had any contact with the Hospital.
Conclusion: It was found that the TAVI´s application is higher in females; however, it´s
recommended to all patients with comorbidities and factors that prevent them from following the
lead of the common treatment – surgical aortic valve replacement. It may be then an effective
technique to improve AS patients’ quality of life, being a powerful alternative in patients with
severe symptomatic AS.
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Salaun, Erwan. "Imagerie multimodale en cardiologie : application à la surveillance des bioprothèses aortiques." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0722/document.
Full textAbstract:
L’incidence et la prévalence des maladies valvulaires sont en augmentation, l’épidémiologie de ces maladies se modifie avec une prépondérance des maladies dégénératives, et le traitement considéré est le plus souvent le remplacement valvulaire prothétique, notamment dans le cadre de la sténose aortique qui est la maladie valvulaire la plus fréquente. Les techniques de remplacement valvulaire et les prothèses valvulaires ont grandement évolué ces dernières années, notamment avec le développement des implantations de prothèses par voie percutanée. Cependant les substituts valvulaires aortiques biologiques sont exposés à des complications diverses mettant en jeu la fonction de la prothèse : fuite péri-prothétique, endocardite infectieuse, dégénérescence des tissus biologiques. Ces complications restent des challenges diagnostiques et l’échographie est l’imagerie de référence. Cependant, l’imagerie cardiaque et valvulaire a réalisé de grands progrès, et l’utilisation d’autres techniques ou modalités d’imagerie peut être une alternative ou un complément à l’exploration par échocardiographie : imagerie par scanner, imagerie par résonance magnétique, imagerie nucléaire. Le recours et la combinaison de ces différentes techniques s’intègrent dans une approche globale, nommée imagerie multimodale. L’objectif général de ce projet de doctorat a été d’étudier l’apport de l’imagerie multimodale dans la surveillance des bioprothèses aortiques et l’évaluation des complications et de la dégénérescence structurelle qui peuvent survenir<br>The incidence and prevalence of heart valve diseases are increasing worldwide. Their epidemiology also changes, and the required treatment is most often a prosthetic valve replacement, especially for aortic stenosis that is the most frequent heart valve disease. Techniques of valve replacement as well as prosthesis themselves have dramatically evolved in recent years, especially with the development of percutaneous transcatheter procedures. However, biologic aortic valve substitutes are at risk of several complications including prosthetic valve dysfunction, paravalvular regurgitation, infective endocarditis and structural valve deterioration. Correctly diagnose any of these complications still is a challenge but echocardiography plays a pivotal role and remains the gold-standard as per diagnostic imaging. Nonwithsanding the fact that echocardiography is the main imaging modality for valvular anomalies, great progress has been made in cardiac imaging and modalities like CT-Scan, MRI and nuclear imaging are nowadays regularly used along with echocardiography. The use and combination of these different techniques are part of a global approach, entitled multi-modality imaging.The general objective of this doctoral project was to study the contribution of the multi-imaging approach in the assessment of the bioprosthesis function and screening for complications and structural valve deterioration that may occur
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Lee, Jang-Sun [Verfasser], and Christian [Akademischer Betreuer] Hagl. "In-vitro Evaluation einer neu entwickelten bio-hybriden tissue-engineerten Aortenklappenprothese zur TAVI-Applikation / Jang-Sun Lee ; Betreuer: Christian Hagl." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1175381446/34.
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Grosse, Volkmar [Verfasser], Bernd-Dieter [Akademischer Betreuer] Gonska, Bernd-Dieter [Gutachter] Gonska, and Theodor [Gutachter] Tirilomis. "Prädikatoren der Schrittmacherpflicht nach perkutanem kathetergestützten Aortenklappenersatz (TAVI) / Volkmar Grosse ; Gutachter: Bernd-Dieter Gonska, Theodor Tirilomis ; Betreuer: Bernd-Dieter Gonska." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1172500843/34.
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Kahlstadt, Lisa [Verfasser]. "Prävalenz und prognostische Relevanz einer Anämie auf die Ergebnisse nach kathetergestütztem Aortenklappenersatz (TAVI) bei Patienten mit schwerer Aortenklappenstenose / Lisa Kahlstadt." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1121745563/34.
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Abdulghafor, Marwan [Verfasser], and Daniel [Akademischer Betreuer] Wendt. "Long- term clinical outcomes after Transcatheter Aortic Valve Implantation (TAVI) in Patients with chronic renal failure / Marwan Abdulghafor ; Betreuer: Daniel Wendt." Duisburg, 2019. http://d-nb.info/1191691896/34.
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Brück, Benedikt [Verfasser], and Ellen [Akademischer Betreuer] Hoffmann. "Prognostische Parameter für den prozeduralen Erfolg und das Ein-Jahres-Überleben nach kathetergestütztem, perkutanem Aortenklappenersatz (TAVI) / Benedikt Brück ; Betreuer: Ellen Hoffmann." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1164377078/34.
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Krau, Nora-Christina [Verfasser]. "Minimal invasiver Aortenklappenersatz (TAVI) bei degenerativer, kalzifizierender Aortenklappenstenose – Risikostratifizierung anhand des neuen Biomarkers Growth Differentiation Factor 15 (GDF15) / Nora-Christina Krau." Kiel : Universitätsbibliothek Kiel, 2018. http://d-nb.info/1165051257/34.
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Schleicher, Mathias [Verfasser], and Malte [Akademischer Betreuer] Kelm. "Sicherheit und Effizienz einer dualen Thrombozyten-Aggregationshemmung mittels Acetylsalicylsäure und Clopidogrel nach Transkatheter Aortenklappen Implantation (TAVI) / Mathias Schleicher. Gutachter: Malte Kelm." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2015. http://d-nb.info/1067999442/34.
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Hartmann, Lisa [Verfasser]. "Evaluation der Aortenklappe in der CT und Korrelation mit paravalvulären Insuffizienzen in Patienten nach Transcatheter Aortic Valve Implantation (TAVI) / Lisa Hartmann." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2015. http://d-nb.info/1076038743/34.
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Sobisiak, Bettina [Verfasser], Wolfgang [Akademischer Betreuer] Schillinger, Roland [Gutachter] Nau, and Margarete [Gutachter] Schön. "Einfluss der Gebrechlichkeit auf Morbidität und Mortalität nach kathetergestützter Aortenklappenimplantation (TAVI) / Bettina Sobisiak ; Gutachter: Roland Nau, Margarete Schön ; Betreuer: Wolfgang Schillinger." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1136131388/34.
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Gripari, P. "MULTIMODALITY IMAGING ASSESSMENT OF THE ANATOMY OF THE AORTIC VALVE APPARATUS IN TAVI PATIENTS: IMPLICATIONS FOR PROSTHESIS SIZING AND PARAVALVULAR REGURGITATION." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/263404.
Full textAbstract:
Aortic stenosis (AS) has become the most frequent type of valvular heart disease in Europe and North America. As it primarily presents as calcific AS in adults of advanced age (2–7% of the population >65 years), its prevalence is expected to increase further in the future with an aging population.
Severe AS is associated with debilitating symptoms (shortness of breath, angina, dizziness, or syncope), and reduced survival if left untreated.
According to European Society of Cardiology guidelines, aortic valve replacement (AVR) is the definitive therapy for all patients with symptoms and severe AS, or severe AS with left ventricular systolic dysfunction. However, approximately the 30% of patients referred for AVR are denied surgery because of advanced age, left ventricular dysfunction or comorbidities. Over the last few years, transcatheter aortic valve implantation (TAVI) has been demonstrated to be a feasible and effective therapeutic alternative to traditional AVR for high-risk surgical patients. Clinical trials have shown TAVI to have outcomes similar to surgical AVR up to 2 years after the procedure and excellent outcomes have been confirmed by registry data, with overall survival of 76% at 1 year.
TAVI is an invasive technique whose success depends on multidisciplinary team approach, where imaging fulfils a definite part. Pre-procedure imaging is vital to assess the severity of AS, identify eligible candidates, plan the interventional approach, and select the appropriate prosthesis according to the anatomical features. Imaging is pivotal during and after the procedure, guiding prosthesis deployment, providing information regarding valve position, identifying immediate complications, and assessing outcomes.
Before TAVI, accurate evaluation of the aortic root dimensions and anatomy is essential for the selection of eligible candidates for the procedure and to ensure the appropriately sized valve prosthesis is chosen.
The objective of this thesis is to investigate the incremental value of a multimodality imaging approach to the evaluation of the anatomy of the aortic valve apparatus in TAVI candidates.
Chapter 1 illustrates the feasibility and accuracy of 3D transthoracic echocardiography (TTE) compared to 2D TTE and multidetector computed tomography (MDCT) for the measurement of aortic annulus dimensions in the preoperatory evaluation of 100 patients candidates to TAVI. 3D TTE evaluation was feasible in the majority of the patients with low intra and inter observer variability. 3D TTE and MDCT measurements did not differ significantly, with excellent agreement in the selection of cases with too small or too large annulus (recognized exclusion criteria for TAVI) while, as expected due to the oval shape of the aortic annulus, the 2D TTE annulus area, geometrically derived from 2D TTE diameter, was considerably lower in comparison both with 3DTTE and MDCT planimetric surface area. A good agreement in the choice of prosthetic size in cases scheduled for the procedure was found between the 3D TTE and MDCT. Subsequently, even though it’s known that MDCT provides precise information about the annulus anatomy and remains the gold standard for the pre-operative assessment of TAVI candidates, 3D TTE may play a role in those patients that can’t be studied by MDCT for several reasons such as impaired renal function, severe breathlessness, and arrhythmias. 3D TTE does not require breath-old and contrast infusion, may be obtained at the bedside, in more critical cases, and also in the presence of arrhythmias.
Chapter 2 shows that cardiac magnetic resonace (CMR), due to its multiplanar reformatting capabilities, allows accurate short-axis visualization of the aortic annulus and precise measurement of the virtual ring corresponding to the site of prosthesis deployment with high reproducibility and accuracy as compared to MDCT. Moreover, it can estimate the coronary ostia height and aortic valve leaflet dimensions that is a key step for patient selection and procedural planning in order to prevent coronary obstruction during TAVI.
In Chapter 3 122 aortic patients were studied to evaluate the capability of 3D transesophageal echocardiography (TEE) to estimate preoperatively the distance between the aortic annulus and the left main ostium (AoA-LM), its accuracy in comparison with MDCT-derived measurements, the ability of the 3DTEE-derived measurements in predicting the stent landing zone as defined by the overlap of the prosthesis with mitral leaflet.
The results demonstrated that 3D TEE may estimates the AoA-LM distance as an alternative technique to MDCT. Moreover, 3D TEE allows an immediate evaluation of the distance between the mitral leaflet and aortic prosthesis after the implantation. This measurement was feasible in most of the cases (90%) and also accurate. In fact the 3D TEE computed prosthesis was similar to the prosthetic nominal value. Pre and post 3D TEE data concerning the valve and prosthesis morphology and simultaneous real time evaluation of the aortic root including the LM coronary ostium give new insights regarding TAVI and its complications.
Chapter 4 suggests that intraoperative 2D and 3D TEE may allow the identification of predictors of significant paravalvular aortic regurgitation (PAR) following successful TAVI. In particular, incomplete device expansion due to aortic valve calcifications is believed to be one of the contributing factors to PAR post-TAVI. In fact, heavily calcified native aortic valves may not allow a perfect apposition of the device along the annulus circumference. Our data, collected in 135 TAVI patients, show that the calcifications of the commissure between the right coronary and non-coronary cusp is related to significant post-procedural PAR. Moreover, the measurement of an “area cover index”, defined as the percentage difference between planimetered aortic annulus area and the nominal prosthesis area, should be considered during patient selection for TAVI. As a low “area cover index” predicts the development of significant post-procedural PAR, this index could be utilized as an additional parameter when choosing the prosthetic size in all those patients with borderline 2D TEE annulus size. Probably a certain degree of prosthetic oversizing is needed in order to minimize the development of significant PAR after the procedure.
Chapter 5 shows that, in accordance with previous results, the lack of congruence between prosthesis and annulus size is associated with significant PAR. MDCT is a valuable modality for detecting the mismatch between prosthesis area and aortic annulus area and for predicting PAR. In details, a mismatch of 61.5 mm2 between prosthesis size and aortic annulus area measured by MDCT is a predictor of PAR.
In conclusion, advanced cardiac imaging modalities (3D echocardiography, MDCT and MRI), besides standard 2D echocardiography and angiography, play a crucial role in the diagnostic process and management of TAVI patients, allowing proper selection and planning, optimizing the procedure and increasing TAVI success. Echocardiography is the cornerstone of pre-procedure evaluation, complemented by MDCT. Both 3D TTE/TEE and MDCT have a higher predictive value for PAR than 2D echo measurements and have been shown to change valve sizing strategy compared with 2D echo. During TAVI, 2D, and particularly 3D, TEE can be used for guidance and, allowing the visualization of the left main ostium and the measurements of its distance from the annulus, increases the procedure safety. In the future, as patients undergoing TAVI might be younger, CMR might gain significance by the absence of radiation issues.
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Peterle, Silvia <1988>. "IMPOSIZIONE SUI SERVIZI COMUNALI: TASI E TARI." Master's Degree Thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/5324.
Full textAbstract:
Alla luce delle recenti novità sul tema dei tributi locali, apportate dalla Legge di Stabilità 2014, si intende fornire un'analisi delle due nuove entrate collegate all'erogazione dei servizi forniti dal Comune alla collettività che vanno a comporre la nuova imposta unica comunale: la TASI destinata a finanziare i costi per i servizi indivisibili e la TARI finalizzata alla copertura dei servizi inerenti al servizio di raccolta e smaltimento dei rifiuti.L'approccio proposto in questa sede prevede dapprima un'analisi tecnica dei vari elementi che strutturano i due prelievi in esame,con una breve evoluzione storico normativo dei servizi considerati per poi giungere ad elaborare considerazioni sulla correttezza dei tributi rispetto al presupposto economico che colpiscono ossia l'utilizzo dei servizi.
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Campelo, Parada Francisco. "Trastornos de conducción tras la implantación de prótesis valvulares aórticas transcatéter: incidencia, caracterización, seguimiento e impacto clínico a largo plazo." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/672586.
Full textAbstract:
Els trastorns de conducció (TdC) representen la complicació més freqüent després de l'implant de vàlvula aòrtica percutània. A pesar que el desenvolupament dels dispositius i el major coneixement de la tècnica han permès reduir de manera significativa la major part de les complicacions, la incidència dels TdC roman estable. Actualment la TAVI és el tractament de referència de les estenosis aòrtiques simptomàtiques en pacients alt risc i es recomana també el seu ús en pacients de risc intermedi. Aquests bons resultats justifiquen avaluar si aquesta tècnica pot aplicar-se també en pacients de baix risc quirúrgic. En el primer treball de recerca d'aquesta tesi s'estudia la incidència de TdC en una cohort de baix risc quirúrgic als quals se'ls va indicar un tractament percutani després de l'avaluació multidisciplinària. Aquesta població més jove i amb menors comorbilidades presenta una incidència de TdC lleugerament inferior a la del grup de risc intermedi o alt, encara que sense diferències estadísticament significatives. Un 25% dels pacients de baix risc presenten un TdC relacionat amb la TAVI i persistent a l'alta. La profunditat d'implantació de la vàlvula és el principal factor predictor de TdC en l'anàlisi multivariada, juntament amb l'amplitud del QRS i el gradient mitjà de la vàlvula aòrtica. Encara que les vàlvules autoexpandibles presenten una major incidència de TdC, aquest tipus de pròtesi no representen un factor predictor independent de TdC, si no que la seva major incidència és secundària a una altura d'implantació significativament més profunda.
En el segon treball de recerca s'estudia la cronologia i evolució dels TdC en un grup de pacients tractats amb vàlvula expandible amb pilota i analitzem l'impacte de la valvuloplastia aòrtica en la incidència de TdC. L'estudi del monitoratge electrocardiográfica va permetre identificar els moments d'aparició dels TdC en el procediment i la seva evolució durant l'hospitalització. Aquesta anàlisi detallada del procediment va identificar que un 51,5% dels TdC apareixen abans d'implantar la vàlvula (durant la manipulació de la guia rígida o la predilatació/valvuloplastia) i que aquests TdC d'aparició primerenca s'associen a una major persistència dels TdC en el seguiment a un mes. En aquest mateix estudi comparem la incidència de TdC del procediment TAVI amb valvuloplastia enfront de l'implant directe de la vàlvula sense valvuloplastia prèvia. El grup tractat amb valvuloplastia va mostrar una taxa de persistència dels TdC significativament major en el seguiment a un mes. Entre els pacients que presenten un TdC a l'alta, l'ús de valvuloplastia va ser l'únic factor que es va associar amb la persistència del TdC en el seguiment.<br>Los trastornos de conducción (TdC) representan la complicación más frecuente tras el implante de válvula aórtica percutánea. A pesar de que el desarrollo de los dispositivos y el mayor conocimiento de la técnica han permitido reducir de forma significativa la mayor parte de las complicaciones, la incidencia de los TdC permanece estable. Actualmente la TAVI es el tratamiento de referencia de las estenosis aórticas sintomáticas en pacientes alto riesgo y se recomienda también su uso en pacientes de riesgo intermedio. Estos buenos resultados justifican evaluar si esta técnica puede aplicarse también en pacientes de bajo riesgo quirúrgico. En el primer trabajo de investigación de esta tesis se estudia la incidencia de TdC en una cohorte de bajo riesgo quirúrgico a los que se les indicó un tratamiento percutáneo tras la evaluación multidisciplinar. Esta población más joven y con menores comorbilidades presenta una incidencia de TdC ligeramente inferior a la del grupo de riesgo intermedio o alto, aunque sin diferencias estadísticamente significativas. Un 25% de los pacientes de bajo riesgo presentan un TdC relacionado con la TAVI y persistente al alta. La profundidad de implantación de la válvula es el principal factor predictor de TdC en el análisis multivariado, junto con la amplitud del QRS y el gradiente medio de la válvula aórtica. Aunque las válvulas autoexpandibles presentan una mayor incidencia de TdC, este tipo de prótesis no representan un factor predictor independiente de TdC, si no que su mayor incidencia es secundaria a una altura de implantación significativamente más profunda.
En el segundo trabajo de investigación se estudia la cronología y evolución de los TdC en un grupo de pacientes tratados con válvula expandible con balón y analizamos el impacto de la valvuloplastia aórtica en la incidencia de TdC. El estudio de la monitorización electrocardiográfica permitió identificar los momentos de aparición de los TdC en el procedimiento y su evolución durante la hospitalización. Este análisis pormenorizado del procedimiento identificó que un 51,5% de los TdC aparecen antes de implantar la válvula (durante la manipulación de la guía rígida o la predilatación/valvuloplastia) y que éstos TdC de aparición temprana se asocian a una mayor persistencia de los TdC en el seguimiento a un mes. En este mismo estudio comparamos la incidencia de TdC del procedimiento TAVI con valvuloplastia frente al implante directo de la válvula sin valvuloplastia previa. El grupo tratado con valvuloplastia mostró una tasa de persistencia de los TdC significativamente mayor en el seguimiento a un mes. Entre los pacientes que presentan un TdC al alta, el uso de valvuloplastia fue el único factor que se asoció con la persistencia del TdC en el seguimiento.<br>The conduction disturbances (CD) are the most common complication after percutaneous aortic valve implantation. Despite that device evolutions and a better understanding of patient selection and preprocedural assessment led to a significant reduction in most of the procedure-related complications, the incidence of CD remains stable over time. Nowadays, TAVI is the gold standard for the treatment of severe symptomatic aortic stenosis in high surgical risk patients and is also recommended in patients at intermediate risk. The excellent results in these patients justify the study of this technique also in lower risk patients. In our research project we assess the incidence of CD in a low surgical risk cohort of patients with a TAVI indication after a Heart Team evaluation. This younger population showed a slightly lower incidence of CD than the intermediate/high risk group, although without statistical significance. Up to 25% of low-risk patients presented with persistent CD related to TAVI at discharge. The depth of valve implantation was identified as the main predictor of CD in multivariate analysis, together with baseline QRS duration and baseline mean aortic gradient. Despite that self-expandable valves showed a higher rate of CD, these valves were not identified as an independent predictor of CD because its higher incidence of CD is secondary to a significantly deeper valve implantation in the left ventricular outflow tract. In our second study we have assessed the timing and evolution of CD in a group of patients undergoing a balloon-expandable valve implantation and the impact of valvuloplasty in the incidence of CD. The continuous electrocardiogram monitoring allowed us to identify the timing of CD and their evolution during hospital stay. This analysis showed that a 51,5% of CD occurred before valve implantation (after stiff-wire placement or valvuloplasty) and these early CD were more frequently persistent at one-month follow-up. In this study we also determine the impact of valvuloplasty in CD. Avoiding the use of valvuloplasty was associated with a lower rate of CD persistence over time. Valvuloplasty was identified as the only independent predictor of CD persistence at one-month follow-up in this study.<br>Universitat Autònoma de Barcelona. Programa de Doctorat en Medicina