Dissertations / Theses: 'Thrombectomie'

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Machi, Paolo. "Evaluation expérimentale des propriétés mécaniques et de l'efficacité d'enlèvement des thrombus des stent retrievers." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT263/document.

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Un certain nombre d'essais cliniques contrôlés, randomisés et publiés récemment en littérature a démontré que la thrombectomie mécanique, offerte aux patients présentant un AVC ischémique aigu, est liée à une meilleure évolution clinique en comparaison au traitement standard de fibrinolyse intraveineuse. Les stents retriever ont été reconnus dans ces essais comme les dispositifs les plus efficaces pour la thrombectomie intracrânienne. Actuellement, toutes les industries produisant des dispositifs neuro-interventionnels lancent sur le marché un nombre croissant de stents retriever. Chaque nouveau dispositif proposé est censé avoir une particularité permettant de meilleures performances par rapport aux dispositifs déjà disponibles sur le marché. Néanmoins, aucune étude clinique n’a démontré, jusqu'à présent, la supériorité en termes de résultats anatomiques et cliniques d'un stent retriever donné. En outre, le mécanisme d'interaction entre les stents retriever et le thrombus n'a pas été évalué jusqu'ici de façon exhaustive. Dans la présente étude, nous avons analysé expérimentalement les performances de tous les stents retriever disponibles sur le marché français jusqu'à juin 2015. Le but de cette étude était d'identifier toutes les caractéristiques des dispositifs fonctionnels à la capture du thrombus. Chaque dispositif a été évalué par des tests mécaniques et fonctionnels : les tests mécaniques ont été effectués afin d'étudier la force radiale des dispositifs. L'objectif était d'évaluer la force radiale exercée par le stent dans deux conditions spécifiques : lors du déploiement et pendant le retrait.Les tests fonctionnels ont visé à évaluer visuellement la capacité du stent à rester en apposition sur la paroi des vaisseaux et à maintenir le thrombus à l'intérieur de ses mailles au cours du retrait. Nous avons évalué l'interaction des dispositifs avec thrombus de taille et de caractéristiques différentes que nous avons générées en utilisant du sang humain afin d'obtenir deux types de caillot : un souple « de type rouge » composé par tous les éléments du sang et un dur « de type blanc» qui a été principalement composé de plasma riche en plaquettes. Ces essais ont été effectués en utilisant un modèle vasculaire rigide reproduisant la circulation cérébrale antérieure. Deux neuro-interventionnels ayant une expérience dans les procédures de thrombectomie ont effectué les tests fonctionnels. Chaque expérience a été filmée et deux auteurs par la suite ont effectué une analyse visuelle des résultats.Les essais mécaniques ont montré un comportement différent en termes de variation de pression radiale au cours du retrait pour chaque stent. Une pression radiale constante pendant le retrait est liée à une cohésion constante sur la paroi artérielle pendant le retrait, avec un taux plus important de retrait du caillot. Tous les stents retriever glissent sur le caillot blanc de grande taille (diamètre>6 mm) ayant un très bas taux d’efficacité en termes de retrait A number of randomized controlled trials recently appeared in literature demonstrated that early mechanical thrombectomy offered to patients presenting with acute ischemic stroke is related to improved functional outcome in comparison to standard care intravenous fibrinolysis. Stent retrievers have been recognized in these trials as the most effective devices for intracranial thrombectomy. Currently, all industries producing neuro-interventional devices are launching into the market an increasing number of stent-based retriever tools. Each new device proposed for clinical use is supposed to have peculiar features allowing better performances in comparison to devices already available for clinical practice. Nevertheless, none clinical study has demonstrated so far the superiority, in terms of anatomical and clinical results, of a given stent retriever device. Furthermore, the mechanism of interaction between stent retrievers and thrombi has not exhaustively evaluated so far. In the present study we experimentally analyzed performances of all stent retrievers available into the French market up to Juin 2015. The aim of this study was to identify any device feature that was functional to the thrombus removal.Stent retrievers were evaluated by mechanical and functional test: mechanical tests were performed in order to investigate devices radial force, the aim was to evaluate the radial force exerted by the stent in two specific conditions: upon deployment and during the retrieval.Functional tests were aimed to visually evaluate the stent retriever’s ability in remaining in close apposition to the vessels wall and to maintain the thrombus engaged within its struts during the retrieval. We evaluated the interaction of the devices with thrombi of different features and sizes that we generated using human blood in order to obtain two types of clot: one softer “red type” that was composed by all elements of the whole blood and one stiffer “white type” that was mainly composed by platelet-rich plasma. Such tests were conducted using a rigid 3D printed vascular model reproducing the brain anterior circulation. Two neuro-interventionalists with experience in thrombectomy procedures performed functional tests, each experiment was filmed and two authors thereafter conducted visual analysis of the results.Mechanical tests showed different behavior in terms of radial pressure variation during retrieval for each stent. Constant radial pressure during retrieval was related to constant cohesion over the vessel wall during retrieval and higher rate of clot removal efficacy. All stent retrievers slide over the clot failing in clot removal when interact with white large thrombi (diameter>6 mm)

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Tardy, Bernard. "Utilité des D-Dimères ELISA dans la prise en charge diagnostique et thérapeutique des thromboses veineuses." Saint-Etienne, 2004. http://www.theses.fr/2004STET011T.

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Utilité des D-dimères ELISA à titre diagnostique : Le but de la première étude était d’évaluer l’intérêt des D-dimères chez 96 patients âgés de plus de 70 ans admis pour suspicion d’EP. Dans cette étude, le dosage ELISA des D-dimères a, pour une valeur seuil inférieur à 500ng/ml , une excellente sensibilité et valeur prédictive négative pour le diagnostic d’exclusion d’une EP. Par contre, sa spécificité est médiocre de l’ordre de 15%. Le but de la deuxième étude était d’évaluer l’intérêt des D-dimères des patients admis pour céphalée aiguë suspecte de thrombose veineuse cérébrale (TVC). La population a consisté en 18 patients avec une TVC et 34 témoins avec céphalée aiguë d’origine migraineuse. Dans cette étude, les D-dimères ELISA ont une excellente valeur prédictive négative (100%) pour le diagnostic d’exclusion de TVC chez les patients présentant des céphalées aiguës. D-dimères ELISA à titre thérapeutique : Le but de la première étude était de comparer l'évolution des Fragments Prothrombiniques 1+2 et des D-dimères après arrêt brutal ou progressif d'un traitement AVK chez des malades traités pour une maladie thromboembolique veineuse. Dans cette étude randomisée et en double aveugle portant sur 20 patients, aucun argument biologique ne supporte l’existence d’un effet rebond lié à l'arrêt brutal du traitement AVK. Le but de la deuxième étude était d’évaluer la cinétique des D-dimères au cours du traitement héparinique des TVC. Les résultats préliminaires sur 17 patients montrent que le taux de D-dimères se normalisent rapidement au cours des traitements adaptés par héparine mais qu’ils stagnent ou augmentent en cas d’extension de la thrombose ou d’insuffisance du traitement anticoagulant.

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MILTGEN, GILLES. "Indications et techniques de la thrombectomie veineuse ilio-femorale : a propos de 74 cas." Aix-Marseille 2, 1988. http://www.theses.fr/1988AIX20493.

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Seners, Pierre. "Recanalisation artérielle précoce après thrombolyse intraveineuse d’un accident ischémique cérébral avec occlusion artérielle proximale : incidence, prédiction et physiopathologie Indicidence and predictors of early recanalization following IV thrombolysis. A systematic review and meta-analysis Post-thrombolysis recanalization in stroke referrals for thrombectomy: Incidence, predictors and prediction scores Relationships between brain perfusion and early recanalization after intravenous thrombolysis for acute stroke with large vessel occlusion Better collaterals are independently associated with post-thrombolysis recanalization before thrombectomy Thrombus length predicts lack of post-thrombolysis early recanalization in minor stroke with large vessel occlusion Early recanalization in tenecteplase vs. alteplase-treated drip-and-ship patients referred for thrombectomy." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB222.

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À la phase aigüe de l’accident ischémique cérébral (AIC) avec occlusion artérielle proximale, la cible thérapeutique principale est l’obtention d’une recanalisation artérielle la plus rapide possible. L’utilisation combinée de la thrombolyse intraveineuse (TIV) par alteplase et de la thrombectomie mécanique (TM), dénommée « bridging therapy » et recommandée depuis 2015, est actuellement remise en question car i) en cas de faible probabilité de recanalisation précoce (RP) post-TIV, celle-ci pourrait être non seulement inutile, mais aussi délétère ; et ii) inversement, si la probabilité de RP est forte, un transfert en centre spécialisé pour TM pourrait s’avérer inutile. Une meilleure compréhension des mécanismes physiopathologiques sous-tendant la résistance à la TIV, et le développement d’outils prédictifs de la survenue de celle-ci, pourraient avoir des implications cliniques importantes, notamment le développement de thérapies intraveineuses plus efficaces ou l’avancée vers une médecine personnalisée sélectionnant le traitement de recanalisation (c’est-à-dire, TIV seule, bridging ou TM seule) le plus adapté à chaque patient. Dans cette thèse, nous avons étudié l’incidence et les facteurs prédictifs de la RP post-TIV dans une large cohorte multicentrique française d’AIC avec occlusion proximale (n=1107), traités par TIV et adressés pour TM entre 2015 et 2017. La RP était évaluée dans les 3h suivant la TIV, sur le premier jet de l’artériographie ou par imagerie vasculaire non-invasive. Notre travail a montré que l’incidence de la RP post-TIV est relativement importante, survenant en moyenne chez 1 patient sur 5. L’analyse des facteurs prédictifs a montré que la localisation du thrombus dans l’arbre artériel, sa longueur, le délai entre la TIV et l’évaluation de la recanalisation, et la qualité du réseau artériel collatéral ou la sévérité de l’hypoperfusion cérébrale, sont associés de manière indépendante à la survenue d’une RP, contribuant de ce fait à la compréhension des mécanismes sous-tendant celle-ci. Un score prédictif original, créé par combinaison des trois premières variables, permettait de prédire l’absence de RP avec une très grande spécificité, mais de façon insuffisamment fiable la survenue d’une RP. Ce score devrait permettre à l’avenir d’aider à la sélection des patients pour des essais randomisés comparant bridging vs. TM seule, mais pas de limiter les « transferts futiles » en TM. Dans le sous-groupe de patients avec déficit neurologique mineur (score NIHSS<6), situation dans laquelle le traitement optimal est actuellement incertain, nous avons montré que la longueur du thrombus est un facteur prédictif puissant de RP, et qu’un seuil de 9mm permet de prédire l’absence de RP avec un bon rapport sensibilité/spécificité, ce qui pourrait aider au dessin d’essais randomisés testant TIV seule vs. bridging dans cette population. Enfin, dans un échantillon de patients nécessitant un transfert inter-hospitalier pour la réalisation de la TM, situation clinique la plus fréquente actuellement, l’incidence de RP n’était pas différente entre patients thrombolysés par tenecteplase (un nouveau thrombolytique prometteur) en comparaison à l’alteplase. La divergence de ce résultat avec ceux de l’essai randomisé de phase II EXTEND-IA TNK qui a rapporté une incidence deux fois plus élevée de RP après tenecteplase dans une population admise directement dans un centre de TM (chez qui le délai thrombolyse-thrombectomie était donc nettement plus court), s’expliquerait par une recanalisation plus précoce après tenecteplase, ce qui, en cas de confirmation par des études futures, pourrait avoir des conséquences cliniques importantes. (...) In acute stroke patients with large-vessel occlusion (LVO), the goal of intravenous thrombolysis (IVT) is to achieve early recanalization. Whether all patients with LVO need to undergo intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) – i.e. bridging therapy, which is standard-of-care since 2015 – is debated as: i) thrombolysis may be harmful in patients unlikely to recanalize following IVT; and, ii) conversely, transfer for MT may be unnecessary in patients highly likely to recanalize. It is therefore timely and important to investigate the mechanisms and predictors of post-IVT recanalization, since the findings could have major clinical implications, such as the development of more efficient intravenous therapies, as well as moving towards personalized medicine, involving the selection of individual patients for best therapy, i.e., IVT alone, bridging, or MT alone. In the present thesis, we studied the incidence and predictors of post-IVT early recanalization in a large French multicentric cohort of acute stroke with LVO (n=1107), where all patients were treated with IVT and referred for MT between 2015 and 2017. Recanalization was evaluated on first intracranial angiogram or non-invasive vascular imaging within the first 3h following IVT start. The incidence of early recanalization following IVT was substantial in the overall cohort, occurring in ~1 in 5 patients. Thrombus site and length, time elapsed between IVT start and recanalization assessment, and quality of the leptomeningeal collateral flow or severity of hypoperfusion, were all independently associated with early recanalization occurrence. These findings are novel and important, and shed new light on the mechanisms underlying post-IVT recanalization. A six-point score derived from the three former variables afforded >90% specificity for no-recanalization, but did not reliably predict occurrence of early recanalization. This score should prove of value for patient selection into trials, testing e.g. bridging therapy vs. MT alone, but may not be used to support decisions to withhold referral for MT. In the subgroup of LVO patients with minor neurological symptoms (NIHSS score <6), in whom the optimal treatment is unknown, we found that thrombus length was a powerful independent predictor of no-recanalization, and that the optimal cutoff (9mm) had a high sensitivity/specificity ratio for no-recanalization, which may help design randomized trials aiming to test bridging therapy vs. IVT alone in this population. Lastly, unlike the EXTEND-IA TNK randomized trial which found 2-fold higher early recanalization rate before mechanical MT following IVT with tenecteplase as compared to alteplase in patients directly admitted to MT-capable centres, we found similar early recanalization rates with these two thrombolytic agents in patients transferred for MT from a non MT-capable centre (i.e., with longer IVT-to-MT delays than in EXTEND-IA TNK), currently the most frequently encountered clinical situation. Taken together, these data suggest that recanalization may occur earlier with tenecteplase, which if confirmed would have clinical relevance. Towards further clarifying the pathophysiology of post-thrombolysis early recanalization failure and develop more efficient intravenous therapies for acute ischemic stroke, specific studies will need to address two additional potentially important predictors of early recanalization, namely haemostatic biomarkers and thrombus composition

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Gory, Benjamin. "Caractérisation IRM d’un modèle murin d’ischémie-reperfusion cérébrale induit par cathétérisme de l’artère cérébrale moyenne et évaluation du post-conditionnement à la Cyclosporine A." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1208/document.

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La reperfusion complète et précoce est le moyen le plus efficace pour limiter l'extension de l'infarctus cérébral et les séquelles neurologiques. Le traitement de l'infarctus cérébral a été révolutionné par la thrombectomie mécanique intra-artérielle en permettant une recanalisation dans plus de 70% des cas et une réduction significative de la morbidité comparativement à la thrombolyse seule pour le territoire carotidien. Le pronostic des occlusions basilaires reste dramatique et aucun essai n'a démontré le bénéfice de l'approche intra-artérielle à l'heure actuelle. Dans la première partie du travail, nous avons réalisé une méta-analyse sur la thrombectomie par «stent-retriever» des occlusions basilaires, à partir des résultats publiés dans MEDLINE entre novembre 2010 et avril 2014: recanalisation angiographique (TICI≥2b)=81% (IC 95%: 73-87); hémorragie cérébrale symptomatique à 24 heures=4% (IC 95%: 2-8); évolution neurologique favorable (mRS≤2 à 3 mois)=42% (IC 95%: 36-48); mortalité=30% (IC 95%: 25-36). L'approche intra-artérielle ouvre une nouvelle ère thérapeutique, cependant un modèle animal adapté et pertinent est nécessaire pour l'évaluation pré-clinique. Dans la deuxième partie du travail, nous avons caractérisé l'évolution spatio-temporelle précoce de l'infarctus par IRM multimodale dans un modèle d'ischémie cérébrale focale transitoire réalisé par occlusion sélective intra-artérielle de l'artère cérébrale moyenne chez le rat adulte. Une occlusion complète de l'artère cérébrale moyenne proximale était observée dans 75% des 16 rats opérés, et un mismatch diffusion/perfusion dans 77% des cas. Le volume ischémique durant l'occlusion artérielle, définie sur la séquence de diffusion, était de 90±64 mm3 et de 57±67 mm3 à 24 heures sur la séquence T2. La recanalisation artérielle s'associe à une reperfusion tissulaire dans 36% des cas. L'hypoperfusion persistait chez la majorité des animaux 3 heures après recanalisation. L'infarctus était de localisation cortical dans 31%, striatale dans 25%, et cortico-striatale dans 44%. Tous les animaux étaient en vie à 24 heures confirmant le caractère mini-invasif de ce modèle. Bien que la reperfusion sauve incontestablement une partie du parenchyme ischémique, elle s'accompagne également de lésions irréversibles spécifiques, dites de reperfusion, s'ajoutant aux lésions initiales. Limiter l'importance des lésions de reperfusion représente un objectif thérapeutique majeur. Dans la troisième partie, nous avons testé l'effet neuroprotecteur de la Cyclosporine A sur la réduction du volume de l'infarctus cérébral et sur le pronostic clinique. Une procédure d'ischémie reperfusion cérébrale de 60 minutes a été réalisée chez 48 animaux, puis ont été randomisés en quatre groupes (groupe témoin, pré-conditionnement, postconditionnement intraveineux et intra-artériel avec la Cyclosporine A à la dose de 10 mg/kg dans les 30 secondes suivant la reperfusion). Sur les 43 animaux inclus dans l'analyse, il n'a pas été observé de réduction du volume ischémique ni une amélioration du pronostic après injection intraveineuse ou intra-artérielle de Cyclosporine A. La Cyclosporine A ne permet pas non plus de limiter l'extension des lésions de reperfusion au sein de la zone à risque à 24 heures de la reperfusion cérébrale Early and complete reperfusion is the most effective therapy to limit the extent of brain infarction. The treatment of acute anterior ischemic stroke has been revolutionized by the intra-arterial mechanical thrombectomy allowing a 70% recanalization rate and a significant reduction of morbidity compared with thrombolysis alone. The prognosis of basilar artery occlusion remains catastrophic, and to date any trial has demonstrated the benefit of intra-arterial approach. In the first part of the work, we conducted a systematic review and meta-analysis of all previous studies of stent retriever thrombectomy in basilar artery occlusion patients between November 2010 and April 2014: recanalization (TICI≥2b)=81% (95% CI: 73-87); symptomatic intracranial haemorrhage at 24 hours=4% (95% CI 2-8); favorable neurological outcome (mRS≤2 at 3 months)=42% (95% CI: 36-48); mortality=30%(95% CI 25-36). Intra-arterial approach opens new avenues for the developement of treatments for brain infarction, but a relevant animal model of acute ischemic stroke is required for preclinical evaluation. In the second part of the work, we evaluated the spatiotemporal evolution of cerebral ischemia by sequential multimodal MRI in a new minimally invasive model of transient focal ischemia by selective intra-arterial occlusion of the middle cerebral artery in rat. A complete occlusion of the proximal portion of the middle cerebral artery was observed in 75% of 16 operated rats, and a mismatch diffusion/perfusion in 77% of cases. Acute stroke volume during arterial occlusion was 90±64 mm3 on diffusion-weighted imaging, and 57±67 mm3 at 24 hours on T2-weighted imaging. Recanalization is associated with tissue reperfusion in 36% of cases. The hypoperfusion persisted in the majority of animals 3 hours after recanalization. Brain infarction was cortical in 31%, striatal in 25%, and corticalstriatal in 44% of cases. All animals were alive at 24 hours, confirming the minimally invasive nature of the model. Although reperfusion saves a portion of ischemic tissue, it also carries specific irreversible damage, called reperfusion injury, in addition to initial damage caused by ischemia. Limiting the size of infarction is a major objective. In the third part, we tested the neuroprotective effect of Cyclosporine A in reducing the lesion volume and functional outcome. A total of 48 adult rats underwent the intra-arterial ischemia reperfusion procedure, and were randomly assigned to four treatment groups (control, preconditioning, intravenous and intra-arterial postconditioning with Cyclosporine A). Intravenous or intra arterial injection of Cyclosporine A at reperfusion does not either reduce the volume of stroke or improve the neurological outcome. Administation of Cyclosporin A at reperfusion does not limit the extension of reperfusion injuries within the ischemic risk area at 24 hours

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Turc, Guillaume. "Prédiction du pronostic fonctionnel de l’infarctus cérébral traité par thrombolyse intraveineuse." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05T043/document.

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La thrombolyse intraveineuse (TIV) est le seul traitement médical autorisé à la phase aiguë de l’infarctus cérébral (IC). Malgré ce traitement, un patient sur deux présente un mauvais pronostic fonctionnel à 3 mois (score mRS>2), ce qui s’explique le plus souvent par l’absence de recanalisation précoce ou la survenue d’une hémorragie intracrânienne symptomatique (sICH). Nos objectifs étaient, d’une part, de déterminer s’il est possible d’estimer le pronostic fonctionnel (mRS) 3 mois après TIV à partir de variables cliniques et IRM disponibles à l’admission, et, d’autre part, d’étudier les relations entre l’évolution au cours des premières 24 heures et le mRS à 3 mois. Nous avons collecté les données cliniques et d’IRM de l’ensemble des patients traités par TIV pour un IC≤4h30 entre 2003 et 2015 à l’hôpital Sainte-Anne. (1) Nous avons proposé le score MRI-DRAGON, un outil simple basé sur 7 variables cliniques et IRM disponibles à l’admission, qui permet une prédiction satisfaisante du mRS>2. 3 mois après un IC traité par TIV (c=0,83 [0,78-0,88]). (2) Nous avons ensuite réalisé une validation externe de ce score sur la cohorte du CHRU de Lille, confirmant qu’il présente une discrimination et une calibration satisfaisantes, malgré une surestimation du risque de mRS>2 en cas de score MRI-DRAGON élevé. (3) Afin d’essayer d’améliorer la prédiction, nous avons étudié les relations entre microsaignements (CMBs) sur l’IRM initiale et pronostic fonctionnel, et montré que le nombre de CMBs n’était pas un prédicteur indépendant du mRS à 3 mois, après ajustement sur les facteurs de confusion (âge, HTA). Nous avons par ailleurs étudié les relations entre l’évolution clinique très précoce après TIV et mRS à 3 mois, à partir de deux situations: (4) Premièrement, l’absence d’amélioration neurologique 1 heure après le début de la TIV en cas d’occlusion artérielle proximale, présente chez 77% des patients et fortement associée au mRS à 3 mois, mais qui n’améliorait pas la prédiction par rapport au score MRI-DRAGON. (5) Deuxièmement, l’aggravation neurologique survenant dans les 24 heures après le début de la TIV (END), dont l’incidence au sein de notre revue systématique était de 14%. (6) Au sein de notre cohorte, la valeur prédictive positive de l’END pour le mRS>2 à 3 mois était de 90%. L’END de cause indéterminée représentait 70% des END, et était associé à l’absence d’antiplaquettaire avant l’admission, la présence d’une occlusion artérielle proximale, d’un important mismatch diffusion-perfusion, et l’absence de recanalisation. Nous avons proposé un score simple permettant de prédire dès l’admission le pronostic fonctionnel à 3 mois d’un patient traité par TIV pour IC aigu. Il pourrait être utilisé pour guider la décision thérapeutique en identifiant les patients ayant une forte probabilité de mRS ≤2 après TIV seule. Par ailleurs, notre travail suggère que la prise en compte des CMBs avant TIV ne permet pas d’améliorer la prédiction pronostique, et que l’association entre CMBs et mRS n’est pas indépendante. Nous participons actuellement à une méta-analyse internationale sur données individuelles visant à déterminer si un sous-groupe de patients avec CMBs présente un risque de sICH si important qu’il pourrait annuler le bénéfice attendu de la TIV. Bien que l’absence d’amélioration neurologique à 1 heure soit fortement associée au mRS>2 à 3 mois, elle ne semble pas être un outil suffisamment robuste pour guider la décision d’une thrombectomie complémentaire à la TIV (bridging therapy), et ne doit donc pas retarder le geste endovasculaire. Enfin, nos résultats suggèrent que la majorité des END sont favorisés par la persistance d’une hypoperfusion cérébrale, et qu’une part d’entre eux pourrait être prochainement évitée, depuis la démonstration fin 2014, de la nette supériorité du bridging therapy par rapport à la TIV seule concernant la recanalisation artérielle. (...) Intravenous thrombolysis (IVT) is the only licensed drug for acute ischemic stroke (AIS). However, about half of the treated patients do not achieve functional independence at 3 months (mRS>2), mostly due to lack of early recanalization or symptomatic intracranial hemorrhage (sICH). Firstly, we aimed to determine if 3-month outcome (mRS) after IVT can be reliably predicted based on clinical and MRI variables available at admission. Secondly, we assessed the relationships between the clinical course within 24 hours after IVT and 3-month mRS. We collected clinical and MRI data of all patients treated by IVT ≤4.5 hrs for AIS between 2003 and 2015 in Sainte-Anne hospital, Paris. (1) We derived the MRI-DRAGON score, a simple tool consisting of 7 clinical and MRI variables available at admission, which can reliably predict 3-month mRS>2 (c-statistic=0.83 [0.78-0.88]). (2) We then performed an external validation of this score in the Lille cohort, showing good discrimination and calibration of the model, despite an overestimation of the risk of mRS>2 in patients with a high MRI-DRAGON score. (3) Trying to find additional predictors of long-term outcome, we showed that the cerebral microbleed (CMB) burden at baseline was not an independent predictor of 3-month mRS after adjusting for confounding factors (age and hypertension).Furthermore, we assessed the relationships between early clinical course after IVT and 3-month mRS, based on two common clinical events: (4) Firstly, the lack of very early neurological improvement (VENI) 1 hour after IVT, which was observed in 77% patients and strongly associated with 3-month mRS, but did not improve the predictive ability of the model when incorporated into the MRI-DRAGON score. (5) Secondly, early neurological deterioration (END) within 24 hours after IVT, occuring in 14% patients in our systematic review and meta-analysis. (6) In our cohort, the positive predictive value of END for 3-month mRS>2 prediction was 90%. END of undetermined cause (ENDunexplained) accounted for 70% of ENDs, and was associated with no prior use of antiplatelets, proximal artery occlusion, DWI-PWI mismatch volume and lack of recanalization. We proposed a simple score to predict 3-month mRS soon after admission in patients treated by IVT for AIS. It may be used to help therapeutic decisions, by identifying patients likely to achieve 3-month mRS ≤2 after IVT alone. We have also shown that CMB burden before IVT is not an independent predictor or 3-month outcome. We participate in an ongoing international individual patient data meta-analysis to determine whether there is a subgroup of patients with CMBs, which seems to have an independent risk of poor 3-month outcome so important that it might outweigh the expected benefit of IVT. Although lack of VENI 1 hour after IVT is strongly associated with 3-month mRS>2, it doesn’t seem to be specific enough to guide decision-making regarding additional thrombectomy (bridging therapy), and should therefore not delay an endovascular procedure. Finally, our results suggest that a persistent cerebral hypoperfusion contributes to most ENDs. Therefore, many ENDs might be avoided in a near future, given the recent proof of the clear superiority of bridging therapy over IVT alone regarding recanalization. This revolution in acute stroke management leads the way to important clinical research perspectives, such as developing a tool to accurately predict 3-month mRS after bridging therapy. Important research efforts will be needed to develop a personalized treatment algorithm, helping to determine which therapeutic option (bridging therapy, IVT alone, thrombectomy alone, or no recanalization therapy) would be the best for each patient

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Xie, Yu. "Facteurs pronostiques en IRM chez les patients présentant un accident vasculaire cérébral ischémique aigu." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0143.

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L'IRM joue un rôle important dans l'évaluation de l'AVC ischémique et la détermination des stratégies de traitement. L'IRM de diffusion et l’IRM de perfusion sont deux séquences essentielles dans l'évaluation de l'AVC ischémique. L'objectif principal de ce travail était d'explorer le rôle prédictif de l'IRM dans l'AVC ischémique, y compris le rôle des paramètres dérivés de l'IRM dans la prédiction de la viabilité des tissus ; la relation entre le volume lésionnel ischémique pré-traitement et le résultat fonctionnel ainsi que l'efficacité de la thrombectomie mécanique ; l'impact de la localisation ischémique pré-traitement sur le résultat fonctionnel après une thrombectomie mécanique. Nos résultats ont montré que le coefficient de diffusion apparent et le débit sanguin cérébral relatif étaient des candidats potentiels pour prédire la viabilité des tissus ; le volume lésionnel de prétraitement était un prédicteur indépendant pour le résultat fonctionnel ; le bénéfice clinique de l'adjonction de la thrombectomie mécanique à la thrombolyse diminuait avec l'augmentation du volume lésionnel; les patients ayant un gros volume lésionnel peuvent encore bénéficier du traitement ; la localisation ischémique a fourni également des informations pronostics importantes pour le résultat fonctionnel. Les résultats globaux de la thèse ont permis de mieux comprendre le rôle de l'IRM dans l'évaluation de l'AVC ischémique aigu, en particulier chez les patients traités par thrombectomie mécanique. Notre travail a fourni une nouvelle perspective dans l'application clinique de l'IRM et a permis de suggérer de futures recherches sur l'imagerie cérébrale ischémique MRI plays an important role in evaluating ischemic stroke and determining the treatment strategies. Diffusion weighted imaging and perfusion weighted imaging are two essential sequences in ischemic stroke assessment. The principal objective of this work was to study the predictive role of MRI in ischemic stroke, including the role of MRI-derived parameters in tissue viability prediction; the relationship of the ischemic lesional volume and the functional outcome and mechanical thrombectomy efficacy; and the impact of the pretreatment ischemic location on functional outcome after mechanical thrombectomy. Our results suggested that apparent diffusion coefficient and relative cerebral blood flow were potential candidates to predict tissue viability; pretreatment lesional volume was an independent predictor for functional outcome; the clinical benefit of adding mechanical thrombectomy to thrombolysis decreased with the increase of lesional volume; however, patients with large lesional volume could still benefit from reperfusion treatment; the pretreatment ischemic location provided important prognostic information for functional outcome. The overall results of the thesis provided a better understanding of the role of MRI in acute ischemic stroke assessment, especially in patients treated with mechanical thrombectomy. Our work provided new perspective in clinical application of MRI and suggested future research of ischemic stroke imaging

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Wateau, Océane. "Mise au point et caractérisation fonctionnelle d'un modèle d'ischémie-reperfusion cérébrale chez le Macaque cynomolgus A non-human primate model of stroke reproducing endovascular thrombectomy and allowing long-term imaging and neurological read-outs." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC401.

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L’accident vasculaire cérébral est une pathologie dévastatrice et constitue l’une des premières causes de handicap acquis dans le monde. La thrombectomie mécanique par voie endovasculaire est en train de changer drastiquement la prise en charge de l’AVC ischémique à la phase aiguë, en permettant une reperfusion rapide des tissus hypoperfusés et en réduisant la taille de l’infarct final. Bien que la reperfusion soit sans aucun doute bénéfique, elle peut également causer des lésions irréversibles des tissus, dites « d’ischémie-reperfusion ». Par conséquent, le développement de stratégies dites neuroprotectrices est essentiel pour contrer ces évènements délétères. Dans ce contexte, des modèles expérimentaux pertinents sont nécessaires pour tester de nouvelles thérapies et répondre à des questions importantes relatives à la progression de l’infarctus malgré une recanalisation réussie, la réversibilité des lésions ischémiques, la perturbation de la barrière hémato-encéphalique, les dommages de reperfusion, tout cela dans le but d’améliorer la récupération fonctionnelle post-infarctus. Durant ma thèse, nous avons développé un nouveau modèle non invasif d’ischémie-reperfusion cérébrale chez le primate non humain (Macaca fascicularis) reposant sur une approche endovasculaire peu invasive permettant une occlusion transitoire de l’artère cérébrale moyenne, puis sa reperfusion. La première partie de mes travaux a été consacrée à la mise au point de la méthode d’occlusion et du suivi neurofonctionnel des animaux grâce à l’utilisation de 3 outils que j’ai développés : une échelle d’évaluation neurologique, un test de dextérité manuelle et un test de réponse différée. La seconde partie de mes travaux a consisté à valider le modèle nouvellement développé et à le caractériser. Nous avons ainsi réussi à évaluer les dommages cérébraux per- et post-occlusion par des mesures innovantes d’imagerie (TEP-IRM multiparamétriques) ainsi que les déficits neurologiques des animaux sur le long terme. Ce nouveau modèle translationnel, proche de la réalité clinique, constitue un outil essentiel et innovant pour la recherche de cibles thérapeutiques visant à améliorer l’efficacité des traitements dans cette nouvelle ère de la thrombectomie Stroke is a devastating disease and is one of the first causes worldwide of acquired disability. Endovascular mechanical thrombectomy is dramatically changing the management of acute ischemic stroke, allowing a quick reperfusion of hypoperfused tissues and reducing the size of the final infarct. Although reperfusion is undoubtedly beneficial, it can also cause irreversible tissue damage. Therefore, the development of so-called neuroprotective strategies is essential to counteract these deleterious events. In this context, relevant experimental models are required for testing new therapies and addressing important questions about infarct progression despite successful recanalization, reversibility of ischemic lesions, blood-brain barrier disruption, reperfusion damage all with the goal of improving functional recovery post-infarction. During my thesis, we developed a minimally invasive non-human primate model of cerebral ischemia-reperfusion (Macaca fascicularis) based on an endovascular approach allowing transient occlusion and recanalization of the middle cerebral artery and its reperfusion. The first part of my work was devoted to the development of the occlusion method and the neurofunctional monitoring of animals thanks to the use of three tools that I developed: a neurological evaluation scale, a hand dexterity task and a delayed response task. In the second part of my work, I validated and characterized the newly developed model. We have thus succeeded in evaluating the brain damages per- and post-occlusion by innovative imaging methods (multiparametric PET-MRI) as well as assessing the long-term neurological deficits of the animals. This new model, similar to the clinical reality, is an essential and innovative tool for the search for therapeutic targets to improve the effectiveness of treatments in the new era of mechanical thrombectomy

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Yameogo, Nobila Valentin. "Impact de la thromboectomie sur les embolies coronaires distales au cours des syndrômes coronaires aigus avec sus décalage du segment ST." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCI012/document.

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L’angioplastie coronaire primaire percutanée est le traitement de choix du syndrome coronarien aigu avec sus-décalage du segment ST (STEMI) avec une efficacité prouvée pour reperméabiliser l’artère coupable. Un flux TIMI (thrombolysis in myocardial infarction) 3 est généralement restauré dans plus de 90% des patients.Cependant, l'embolisation distale d'un thrombus angiographiquement visible (EDAV) a été identifiée comme l'une des complications majeures de l’angioplastie primaire dans le STEMI, car elle limite l'efficacité de la reperfusion myocardique et conduit à un plus mauvais pronostic.Notre objectif était de déterminer la fréquence des EDAV au cours de l’angioplastie primaire pour STEMI et d’en identifier les facteurs déterminants.Nous avons évalué 779 patients dont 560 hommes (71,9 %) victimes de STEMI et traités par angioplastie primaire. La thromboaspiration était réalisée dans plus de la moitié des cas (53%).L’âge moyen des patients était de 64,03 ± 14,67 ans. Les EDAV étaient fréquentes, de l’ordre de 15%.Les facteurs indépendants liés à la survenue d’EDAV étaient des facteurs cliniques à savoir l’âge > 60 ans, le sexe féminin, la thrombectomie, et la coronaire droite coupable. Aucun critère de la lésion coupable n’a été identifié comme prédicteur d’EDAV.Chez les patients thrombectomisés, les EDAV survenaient dans 17,41% des cas. Les facteurs prédictifs indépendants de ces embolies distales étaient l’atteinte de la coronaire droite et un diamètre de référence de l’artère coupable ˃ 3 mm.Dans la mesure où le succès de la thrombectomie restaure le flux coronaire, nous nous sommes intéressés à la relation entre le succès de cette technique et la survenue des EDAV. Ce travail a montré que la survenue des EDAV n’était liée ni au score syntax, ni au succès de la thrombectomie, mais à deux critères angiographiques à savoir l’atteinte de la coronaire droite et un diamètre de l’artère coupable supérieur à 3 mm.Ces données suggèrent que la coronaire droite est l’élément central de survenue des EDAV. Il s’agit d’une artère double coudée et habituellement de gros calibre. Il semble de ce fait nécessaire de mener des ’études spécifiques sur la coronaire droite Percutaneous primary coronary angioplasty is the cornerstone for acute coronary syndrome with ST segment elevation (STEMI) treatment with proven efficacy to restore flow in culprit coronary artery. A TIMI (thrombolysis in myocardial infarction) 3 flow is generally restored in more than 90 % of patients. However, distal embolization of an angiographically visible thrombus (EDAV) has been identified as one of the major complications of primary angioplasty in STEMI because it limits the effectiveness of myocardial reperfusion and leads to a worse prognosis.Our objective was to determine the frequency of EDAVs during primary angioplasty for STEMI and to identify the determining factors.We evaluated 779 patients, including 560 men (71.9%) suffering from STEMI and treated with primary angioplasty. Thromboaspiration was performed in more than half of the cases (53%). The mean age of the patients was 64.03 ± 14.67 years. EDAVs were frequent (15%). Independent factors related to the occurrence of EDAV were clinical factors such as age > 60 years, female sex, thrombectomy, and culprit right coronary. No criterion from culprit lesion was identified as predictors of EDAV.In thrombectomized patients, EDAVs occurred in 17.41 % of cases. Independent predictor factors of these distal embolisms were right coronary artery target and culprit artery diameter ˃ 3 mm.Since the success of thrombectomy restores coronary flow, we are interested in the relationship between the success of this technique and the occurrence of EDAV. This work showed that the occurrence of EDAV was not related to the syntactic score nor to the success of the thrombectomy but to two angiographic criteria, namely right coronary artery disease and culprit artery diameter greater than 3 mm.These data suggest that right coronary artery is the central component of EDAV occurrence. It is a double bent artery and usually of large caliber. It therefore seems necessary to carry out specific studies on the right coronary artery

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Aleu, Bonaut Aitziber. "Stentriever thrombectomy for stroke within and beyond the time window." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/393973.

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Recientemente se ha aprobado el tratamiento endovascular(TEV) para el ictus por oclusión de gran vaso, lo cual ha cambiado radicalmente el pronóstico infausto de estos pacientes. Una de las contraindicaciones para el TEV es que el paciente llegue más alá de la ventana terapéutica (VT), que tradicionalmente era de 8 horas y actualmente es de 6 horas. La VT se define como el tiempo transcurrido desde el inicio de los síntomas hasta la punción femoral. En pacientes en quienes el inicio del ictus es desconocido, bien porque ocurrió durante el sueño o bien porque el paciente no puede decirlo y no había testigos, la hora de inicio se considera la última vez que el paciente fue visto bien. Estos pacientes caen fuera de VT porque llegan demasiado tarde para ser tratados. Otros pacientes que quedan fuera de VT, son aquellos que tienen una hora de inicio conocida pero que llegan tarde al hospital. Sin embargo, existen evidencias crecientes que la velocidad a la que progresa la isquemia tras una oclusión arterial, varia notablemente entre individuos. Así, mientras que en unos pacientes el territorio arterial está infartado en 6 horas, en otro puede que el infarto no esté establecido hasta las 10 horas. Este concepto choca con el enfoque actual de tratamiento basado en el tiempo, que establece que un paciente se trate en función del tiempo desde el inicio siempre que no haya un gran área infartada. En enfoque basado en la viabilidad del tejido ignora la hora de inicio del ictus. Así para tratar o no a un paciente, se realiza una neuroimagen para confirmar que hay tejido viable, si es así, se realiza el TEV independientemente del tiempo transcurrido. Hay estudios randomizados en marcha para demostrar esta hipótesis, y se han publicado estudios concluyendo que la seguridad y el buen pronostico es similar en pacientes fuera y dentro de ventana. Sin embargo, la mayoría de dichos estudios fueron realizados con dispositivos de primera generación, y algunos reportan pacientes de circulación anterior y posterior. Los stentrievers(ST), dispositivos de nueva generación han demostrado mayores tasas de recanalización y buen pronostico, de hecho las guías actuales recomiendan el TEV con ST. El objetivo primario de esta tesis fue comparar la seguridad y pronóstico de pacientes con ictus de circulación anterior fuera de ventana, tratados mediante TEV con ST, con los pacientes dentro de ventana(WTW). De un total de 468 pacientes 292(63.4%) estaban fuera de ventana(OTW) y 176(37.6%) dentro de ventana. El grupo fuera de ventana, se dividió en dos subgrupos de acuerdo a la hora de inicio: desconocida (UKO) in 113 (24.1%)pacientes y conocida con presentación tardía (KO-LP) en 63(13.5%) pacientes. Estos subgrupos no se pudieron agrupar en el grupo OTW porque un análisis estadístico previo mostró que no eran comparables. Por tanto, los resultados de estos pacientes se presentan de modo separado y comparados con pacientes dentro de ventana. No se encontraron diferencias significativas en buen pronóstico a 3 meses, con 49% en WTW, 42.2%% en UKO y 37.3% en KO-LP. Respecto a la seguridad, tampoco se encontraron diferencias en hemorragia intracraneal sintomática (6.2%WTW, 2.7%UKO y 9.5%KO-LP). Estos hallazgos apoyan el enfoque de viabilidad tisular en vez del basado en tiempo, en pacientes con ictus de circulación anterior tratados con EVT y ST, y seleccionados por neuroimagen, hasta que estén disponibles los resultados de los estudios randomizados. De ser positivos, uno de cada 3 pacientes que normalmente no se tratan por estar fuera de la VT podría ser tratado según nuestro estudio. Endovascular therapy (EVT) for stroke due to large vessel occlusion has been recently approved, changing dramatically the outcome of these patients, who otherwise would have a dismal outcome. However, there are patients automatically excluded from EVT because they arrive beyond the therapeutic time window. Traditionally, the time window (TW) for EVT has been 8 hours but the recent guidelines shortened the window to 6 hours. The TW is defined as the time from symptom onset to the time of groin puncture. In patients in whom the stroke onset is unclear either because the stroke occurred while sleeping or because the patient is unable to tell the onset because is aphasic on unconscious, and no witness is available, the onset is considered the last time the patient was seen normal. These patients often fall outside the window (OTW), because are too late to be treated. Other patients that are too late to be treated are those who, despite having a clear time of onset, arrive OTW. However, there is growing evidence showing that the speed at which the ischemia evolves after an arterial occlusion, varies significantly among individuals. Thus, while in some patients the arterial territory is infarcted in 6 hours, in other, the infarct might not be established after 10 hours. This concept radically challenges the current time-based approach, which establishes whether a patient should be treated or not based on the time from onset provided there is not a large area of infarcted tissue. Interestingly, the tissue-based approach disregards the time from onset. Consequently, the criteria to decide whether to treat a patient or not, would be to image the brain to find out if there is viable tissue, if so, treatment should be carried forward irrespective of the time since stroke onset. There are ongoing trials to prove this hypothesis, and non-controlled studies have been published showing that patients treated OTW have comparable safety and favorable outcomes than those treated within the window. However, those studies were performed with first generation devices and some refer to anterior and posterior circulation strokes. Regarding new generation strategies, stentrievers (ST) have demonstrated higher rates of recanalization and better outcomes. Current guidelines recommend the use of ST. The primary aim of this work was to compare the outcomes and safety of patients OTW with stroke due to anterior circulation (AC) occlusion treated with EVT with ST and selected by neuroimaging with the safety and outcomes of patients WTW. From a total of 468 patients, 292(63.4%) were patients WTW and 176 (37.6%)OTW. The group OTW was divided in two subgroups according to onset: unknown time of onset (UKO) in 113 (24.1%) patients and known onset but late presenters (KO-LP) in 63 (13.5%) patients. These subgroups could not be merged because p statistical analysis showed that they were not comparable, thus, the results had to be presented separately and compared with the WTW group. Regarding outcome, there were no significant differences good outcome at 3 months, with rates of 49% in WTW, 42.2%% in UKO and 37.3% in KO-LP. Regarding safety, there were no significant differences in symptomatic intracranial hemorrhage across groups (6.2%WTW, 2.7%UKO y 9.5%KO-LP). These findings support the tissue- based approach in patients with stroke due to AC occlusion treated with EVT using ST, and selected by neuroimaging, until the results of the randomized trials arrive. According to our study, a positive result would have a great impact on at least, one out of three patients that arrive OTW and are currently left untreated.

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Lin, Hannah. "Factors Associated with Mortality After Undergoing Thrombectomy for Acute Ischemic Stroke." eScholarship@UMMS, 2020. https://escholarship.umassmed.edu/gsbs_diss/1085.

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Background: Mechanical thrombectomy is the gold standard for treating patients with certain acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, even with major advancements and increasing procedural volumes, acute endovascular therapy remains a high-risk procedure with a considerable 90-day mortality rate, affected by a variety of factors. Purpose: To investigate various clinical and procedural factors associated with 90-day mortality in patients undergoing mechanical thrombectomy for emergent treatment of AIS and determine which of these factors made unique contributions to post-thrombectomy prognosis. Methods: We examined a prospective registry of 323 patients treated with endovascular thrombectomy for AIS between 2016 and 2019 at a high-volume comprehensive stroke center in central Massachusetts. We developed two multivariable logistic regression models adjusting for the contributions of baseline characteristics and recanalization parameters, to identify potential predictors of mortality at 90 days. Results: Among 323 AIS patients treated with mechanical thrombectomy, the overall rate of successful recanalization was 86% and the overall post-procedure mortality rate was 29% by 90 days. After univariate analysis, a baseline multivariable model comprised of: history of stroke (OR 0.28, 95% CI 0.09 – 0.68), pre-stroke modified Rankin Scale (mRS 2: OR 3.75, 95% CI), severe admission National Institutes of Health Stroke Scale (NIHSS 21–42: OR 12.36, 95% CI 1.48 – 103.27), internal carotid artery (ICA) occlusion (OR 2.77, 95% CI 1.18 – 6.55), and posterior circulation occlusion (OR 2.69, 95% CI 1.06 – 6.83) was prognostic of 90-day mortality. A second multivariable model also found the procedural factors of: clot obtained after each pass (OR 0.49, 95% CI 0.24 – 1.00), successful recanalization (OR 0.21, 95% CI 0.06 – 0.8) and symptomatic intracranial hemorrhage (sICH; OR 17.89, 95% CI 5.22 – 61.29) to be identifiable predictors of post-thrombectomy mortality. Conclusion: Death within 90 days after thrombectomy was increased among patients with higher pre-stroke disability, higher stroke severity on admission, ICA or posterior occlusion, and those with sICH complication. A history of stroke, clot extraction after each device pass, and successful recanalization are associated with decreased 90-day mortality. These identifiable contributors may inform patient selection, prognosis evolution, and shared decision-making regarding emergent thrombectomy for treatment of AIS.

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Ommen, G. V. A. van. "The hydrolyser a hydrodynamic thrombectomy catheter to remove thrombi from the cardiovascular system /." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Maastricht University [Host], 1998. http://arno.unimaas.nl/show.cgi?fid=8394.

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Koludrovich, Michael. "Design, Analysis, and Experimental Evaluation of a Superelastic NiTi Minimally Invasive Thrombectomy Device." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1399370551.

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Puffer, Andrew James. "Design and Testing of a Minimally Invasive Blood Clot Removal Device Constructed With Elements of Superelastic Nitinol." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1399558753.

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Rajput, Furqan Ahmed [Verfasser]. "Einfluss des Zeitfensters auf das Infarktwachstum bei mittels mechanischer Thrombektomie behandelten Schlaganfallpatienten : Impact of time window on infarct growth in stroke patients treated with mechanical thrombectomy / Furqan Ahmed Rajput." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2020. http://d-nb.info/1221084046/34.

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Shennib, H., K. Hickle, and B. Bowles. "Axillary vein thrombosis induced by an increasingly popular oscillating dumbbell exercise device: a case report." BioMed Central, 2015. http://hdl.handle.net/10150/610314.

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A 53 year-old male presented with a one-day history of a swollen arm and dull, aching pain in the right upper extremity. The patient reported commencing exercising daily over the prior week with a modified, oscillating dumbbell; commonly referred to as a Shake Weight. Imaging revealed an occlusive thrombus in the right axillary, proximal brachial and basilic veins. The patient was treated with a 24-hour tPA infusion followed by mechanical thrombectomy, balloon angioplasty, and stent placement for a residual thrombus and stenosis. The patient was discharged the following day on warfarin and aspirin. This is the first report of effort-induced thrombosis of the upper extremity following the use of a modified, oscillating dumbbell. Due to the growing popularity of modified dumbbells and the possible risk for axillary vein thrombosis, consideration should be made to caution consumers of this potential complication.

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Nakiri, Guilherme Seizem. "Experiência da trombectomia mecânica no tratamento do acidente vascular cerebral agudo em um hospital universitário brasileiro." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/17/17138/tde-23072018-145034/.

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O Brasil é um país em desenvolvimento que luta para reduzir sua desigualdade social extrema. Isso se reflete na falta de infraestrutura de cuidados de saúde, principalmente para a classe de baixa renda, que depende exclusivamente do sistema de saúde pública. No Brasil, menos de 1% dos pacientes com acidente vascular cerebral (AVC) têm acesso a trombólise intravenosa em uma unidade especializada de AVC e as limitações para a implementação da trombectomia mecânica nos hospitais públicos aumentam a carga social do AVC. Objetivo: Avaliar a viabilidade da trombectomia mecânica como parte do tratamento de rotina em um hospital universitário público brasileiro. Pacientes e Métodos: Foram coletados dados prospectivos de todos os pacientes com acidente vascular cerebral isquêmico (AVCI) agudo tratados por trombectomia mecânica de junho de 2011 a março de 2016. A trombectomia combinada foi realizada em pacientes elegíveis para trombólise intravenosa e com presença de oclusão de grandes artérias. Para os pacientes não elegíveis para trombólise intravenosa, foi realizada a trombectomia mecânica desde que não existisse evidência de isquemia significativa de circulação anterior (escala de pontuação Alberta Stroke Program Early CT > 6), dentro de uma janela de tempo de 6 horas; e também para pacientes com AVCI ao desperdar ou de circulação posterior, independente do tempo de início dos sintomas. Resultados: Um total de 161 pacientes foram avaliados, resultando em uma taxa de recanalização global bem sucedida de 76% e taxa de hemorragia intracraniana sintomática de 6,8%. Após 3 meses, 36% dos pacientes apresentaram um índice da Escala de Rankin modificada inferior ou igual a 2. A taxa de mortalidade geral foi de 23%. Conclusão: Nosso estudo foi a primeira série grande de trombectomia mecânica no Brasil e demonstrou resultados aceitáveis de eficácia e segurança, mesmo em condições restritas, fora do cenário ideal dos estudos clínicos randomizados. Brazil is a developing country struggling to reduce its extreme social inequality, which is reflected on shortage of health-care infrastructure, mainly to the low-income class, which depends exclusively on the public health system. In Brazil, less than 1% of stroke patients have access to intravenous thrombolysis in a stroke unit, and constraints to the development of mechanical thrombectomy in the public health system increase the social burden of stroke. Objective: Report the feasibility of mechanical thrombectomy as part of routine stroke care in a Brazilian public university hospital. Patients and methods: Prospective data were collected from all patients treated for acute ischemic stroke with mechanical thrombectomy from June 2011 to March 2016. Combined thrombectomy was performed in eligible patients for intravenous thrombolysis if they presented occlusion of large artery. For those patients ineligible for intravenous thrombolysis, primary thrombectomy was performed as long as there was no evidence of significant ischemia for anterior circulation stroke (Alberta Stroke Program Early CT score >6) within a 6-hour time window, and also for those patients with wake-up stroke or posterior circulation stroke, regardless of the time of symptoms onset. Results: A total of 161 patients were evaluated, resulting in an overall successful recanalization rate of 76% and symptomatic intracranial hemorrhage rate of 6.8%. At 3 months, 36% of the patients had modified Rankin Scale score less than or equal to 2. The overall mortality rate was 23%. Conclusion: Our study, the first ever large series of mechanical thrombectomy in Brazil, demonstrates acceptable efficacy and safety results, even under restricted conditions outside the ideal scenario of trial studies.

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Cabral, Fernando Bermudes. "Estudo das lesões hiperdensas em tomografias computadorizadas de crânio de pacientes submetidos a tratamento endovascular para o acidente vascular cerebral isquêmico agudo." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/17/17158/tde-01022016-145219/.

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INTRODUÇÃO: As imagens de lesões hiperdensas encontradas em exames de tomografia (TC) de crânio após o tratamento endovascular do acidente vascular cerebral isquêmico (AVCi) agudo têm sido correlacionadas ao risco de transformação hemorrágica após o AVC. Entretanto, a correlação entre as lesões hiperdensas e a área cerebral infartada é desconhecida. O objetivo deste estudo é determinar a correlação entre as lesões hiperdensas encontradas em TC de crânio realizadas logo após tratamento endovascular do AVCi agudo e a área de AVC isquêmico. MATERIAIS E MÉTODOS: Foram coletados retrospectivamente dados radiológicos de pacientes com AVCi agudo por oclusão de grandes vasos da circulação anterior submetidos ao tratamento endovascular. Foram analisadas imagens de TC de crânio nas primeiras 24 horas e até 21 dias após o tratamento. As áreas hiperdensas foram classificadas utilizando o escore ASPECTS e comparadas com as áreas de AVC isquêmico final pelo mesmo escore. As imagens foram analisadas independentemente por dois avaliadores, sendo que um terceiro avaliador analisou os casos discordantes. A concordância entre avaliadores (CCI) e os valores de sensibilidade, especificidade, preditivos positivo e negativos e acurácia foram calculados. RESULTADOS: Lesões hiperdensas foram encontradas em 71 dos 93 (76,34%) pacientes com AVC isquêmico de circulação anterior. As áreas captantes de contraste corresponderam às áreas de AVC final segundo o escore ASPECTS (CCI=0,58 [0,40 0,71]). Os valores para cada região individual foram avaliados e a sensibilidade variou de 58,3% a 96,9%, a especificidade de 42,9% a 95,6%, os valores preditivos positivos de 71,4% a 97,7%, os valores preditivos negativos de 53,8% a 79,5% e os valores de acurácia de 0,68 a 0,91. Os maiores valores de sensibilidade foram encontrados para os núcleos lentiforme (96,9%) e caudado (80,4%) e para a cápsula interna (87,5%) e os menores para os córtices M1 (58,3%) e M6 (66,7%). CONCLUSÕES: A aplicação do escore ASPECTS para avaliação das imagens de tomografia de crânio após o tratamento endovascular do AVCi agudo que apresentam captação de contraste, demonstrou ser uma ferramenta útil para a predição da área final de infarto cerebral. A predição foi maior na região profunda e menor nos córtices cerebrais, provavelmente devido maior circulação colateral cortical. Além disso, o método se mostrou reprodutível e de fácil utilização. INTRODUCTION: The hyperdense lesions images found in head computed tomography (CT) scan after endovascular treatment have been correlated to risk of hemorrhagic transformation after stroke. However, the correlation between hyperdense lesions and the infarcted brain area is unknown. The aim of this study is to determine the correlation between the hyperdense lesions found on CT scan performed after endovacular treatment of acute stroke and final ischemic stroke area. MATERIALS AND METHODS: It was collected radiological data of patients with acute ischemic stroke by occlusion of large vessels in the anterior circulation were treated with endovascular treatment. Head CT scan were evaluated in the first 24 hours and by 21 days after treatment. The hyperdense areas were rated using the ASPECTS score and compared with final ischemic stroke by the same score. The images were analyzed independently by two reviewers, and a third evaluator examined the discordant cases. The interrater agreement (ICC) and the sensitivity, specificity, positive and negative predictive values and accuracy were calculated. RESULTS: hyperdense lesions were found in 71 of 93 (76.34%) patients with ischemic stroke of anterior circulation. The contrast iodineaccumulating areas corresponded to the final stroke areas (ICC = 0.58 [0.40 to 0.71]) as the ASPECTS score. The values for each individual region were evaluated and the sensitivity ranged from 58.3% to 96.9%, specificity of 42.9% to 95.6%, the positive predictive value of 71.4% to 97, 7%, the negative predictive value of 53.8% to 79.5% and the accuracy of values from 0.68 to 0.91. The higher sensitivity found for lenticular nuclei (96.9%) and caudate (80.4%) and the internal capsule (87.5%) and lower for M1 (58.3%) and M6 (66.7%) cortices. CONCLUSIONS: The use of the ASPECTS score for evaluation of CT head scan after endovascular treatment of acute ischemic stroke images that exhibit contrast enhancement proved to be a useful tool for predicting the final ischemic stroke area. The prediction was higher in the deep region and lower in the cerebral cortex, probably because the cortical collateral circulation. Futhermore, these method was reproducible and easy to use.

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Chueh, Juyu. "Mechanical Flow Restoration in Acute Ischemic Stroke: A Model System of Cerebrovascular Occlusion: A Dissertation." eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/493.

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Stroke is the third most common cause of death and a leading cause of disability in the United States. The existing treatments of acute ischemic stroke (AIS) involve pharmaceutical thrombolytic therapy and/or mechanical thrombectomy. The Food and Drug Administration (FDA)-approved recombinant tissue plasminogen activator (tPA) administration for treatment of stroke is efficacious, but has a short treatment time window and is associated with a risk of symptomatic hemorrhage. Other than tPA, the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) retriever system and the Penumbra Aspiration system are both approved by the FDA for retrieval of thromboemboli in AIS patients. However, the previous clinical studies have shown that the recanalization rate of the MERCI system and the clinical outcome of the Penumbra system are not optimal. To identify the variables which could affect the performance of the thrombectomy devices, much effort has been devoted to evaluate thrombectomy devices in model systems, both in vivo and in vitro, of vascular occlusion. The goal of this study is to establish a physiologically realistic, in vitro model system for the preclinical assessment of mechanical thrombectomy devices. In this study, the model system of cerebrovascular occlusion was mainly composed of a human vascular replica, an embolus analogue (EA), and a simulated physiologic mock circulation system. The human vascular replica represents the geometry of the internal carotid artery (ICA)/middle cerebral artery (MCA) that is derived from image data in a population of patients. The features of the vasculature were characterized in terms of average curvature (AC), diameter, and length, and were used to determine the representative model. A batch manufacturing was developed to prepare the silicone replica. The EA is a much neglected component of model systems currently. To address this limitation, extensive mechanical characterization of commonly used EAs was performed. Importantly, the properties of the EAs were compared to specimens extracted from patients. In the preliminary tests of our model system, we selected a bovine EA with stiffness similar to the thrombi retrieved from the atherosclerotic plaques. This EA was used to create an occlusion in the aforesaid replica. The thrombectomy devices tested included the MERCI L5 Retriever, Penumbra system 054, Enterprise stent, and an ultrasound waveguide device. The primary efficacy endpoint was the amount of blood flow restored, and the primary safety endpoint was an analysis of clot fragments generated and their size distribution. A physiologically realistic model system of cerebrovascular occlusion was successfully built and applied for preclinical evaluation of thrombectomy devices. The recanalization rate of the thrombectomy device was related to the ability of the device to capture the EA during the removal of the device and the geometry of the cerebrovasculature. The risk of the embolic shower was influenced by the mechanical properties of the EA and the design of the thrombectomy device.

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Filho, José Ronaldo Mont\'Alverne. "Efeito dos novos antiagregantes plaquetários prasugrel e ticagrelor administrados upstream sobre os achados angiográficos da angioplastia primária." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-27102015-113637/.

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Introdução. A dupla antiagregação plaquetária traz benefícios no tratamento do infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAMSST). Há variabilidade intra e interindividual no uso do clopidogrel e isso influencia no benefício do seu uso nesse grupo de pacientes. O objetivo desta pesquisa foi avaliar os efeitos de novo antiagregantes plaquetários (prasugrel e ticagrelor) administrados na sala de emergência (\"upstream\") sobre o resultado angiográfico da angioplastia primária, levando em conta o fluxo coronariano TIMI, o blush miocárdico e a carga de trombo. Métodos. Foi realizado um ensaio clínico, randomizado, cego, com 131 pacientes admitidos com IAMSST. Todos os pacientes receberam ácido acetilsalicílico (AAS). Os pacientes foram randomizados para receber clopidogrel (n=44), prasugrel (n=41) ou ticagrelor (n=46) como dose de ataque ainda na emergência. Todos os pacientes foram submetidos a aspiração manual de trombos. Ao término do procedimento, o resultado angiográfico foi avaliado quanto ao fluxo TIMI, o blush miocárdico e a carga de trombo. Resultados. O fluxo coronariano TIMI >= 1 antes do procedimento foi observado mais frequentemente com o uso de ticagrelor (n = 10, 21,7%) do que com o clopidogrel (n = 1, 2,3%) e prasugrel (n = 5, 12,2%; p = 0,019). O fluxo TIMI coronária no fim do procedimento não diferiu significativamente entre os grupos (p = 0,101). Melhor resultado no que diz respeito ao blush miocárdico foi observada com prasugrel, que produziu um grau de blush III em 85,4% (n = 35) dos pacientes, em comparação com o clopidogrel (54,5%; n = 24) e ticagrelor (67,4%; n = 31; p = 0,025). A carga de trombo pré-procedimento foi maior no grupo de clopidogrel, em que 97,7% (n = 43) dos casos denotaram carga de trombo grau 4/5, enquanto 87,8% (n = 36) do grupo prasugrel tiveram respostas semelhantes, e 80,4% (n = 37) foram observadas no grupo ticagrelor (p = 0,03). Conclusão. Os novos antiagregantes plaquetários ticagrelor e prasugrel parecem exercer efeito sobre o resultado angiográfico dos pacientes submetidos a angioplastia primária. O uso do ticagrelor propiciou menor carga de trombo e um fluxo TIMI melhor no pré-procedimento e o uso do prasugrel ensejou melhor perfusão miocárdica analisada pelo blush miocárdico. Não houve diferença no fluxo angiográfico TIMI pós procedimento Introduction. Dual antiplatelet therapy has benefits in the treatment of acute myocardial infarction with ST-segment elevation (STEMI). There is variability intra and inter individual in the use of clopidogrel and this influences the benefit of its use in this group of patients. The objective of this research was to evaluate the angiographic results of Upstream Clopidogrel, Prasugrel, or Ticagrelor For Patients Treated With Primary Angioplasty. Methods. A clinical trial was conducted, randomized, double blind, with 131 patients admitted with STEMI. All patients received acetylsalicylic acid (ASA). Patients were randomized to receive clopidogrel (n = 44), prasugrel (n = 41) or ticagrelor (n = 46) as loading dose even in emergency. All patients were submitted to manual thrombus aspiration. At the end of the procedure, the angiographic result was evaluated for TIMI flow, myocardial blush and thrombus burden. Results. A coronary TIMI flow >= 1 before the percutaneous procedure was observed more frequently with the use of ticagrelor (n=10, 21.7%) than with clopidogrel (n=1, 2.3%) and prasugrel (n=5, 12.2%; p=0.019). The coronary TIMI flow at the end of the procedure did not significantly differ between the groups (p=0.101). A better result with respect to myocardial blush was observed with prasugrel, which yielded a blush grade of III in 85.4% (n=35) of patients, compared with clopidogrel (54.5%; n=24) and ticagrelor (67.4%; n=31; p=0.025). The pre-procedural thrombus burden was found to be of a higher grade in the clopidogrel group, in which 97.7% (n=43) of the cases exhibited thrombus burdens grade 4/5, whereas 87.8% (n=36) of the prasugrel group had similar responses, and 80.4% (n=37) were observed in the ticagrelor group (p=0.03). Conclusions. The novel antiplatelet agents represented by ticagrelor and prasugrel appear to have effect on the angiographic outcome of patients undergoing primary angioplasty. The use of ticagrelor led to a smaller thrombus burden and better TIMI flow at the beginning of the procedure and the use of prasugrel produced a better myocardial perfusion analyzed by myocardial blush. There was no difference in post angioplasty TIMI flow

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Costa, André Jorge Assunção. "Early Transcranial Color-Coded Sonography as a predictor of Hemorrhagic Transformation after Thrombectomy." Master's thesis, 2018. http://hdl.handle.net/10316/89620.

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Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina Introdução: Terapêuticas endovasculares têm alcançado taxas de reperfusão altas e resultados clínicos excelentes, contudo podem causar lesão de reperfusão, que por sua vez está na origem da ocorrência de transformação hemorrágica (TH). O Doppler transcraniano codificado a cores (DTCC) é uma ferramenta diagnóstica válida utilizada na patologia cerebrovascular. Foi nosso objetivo avaliar a capacidade preditora de transformação hemorrágica da realização de DTCC precoce em doentes submetidos a trombectomia e recanalizados devido a um acidente vascular cerebral isquémico (AVCi) com oclusão de grande vaso.Métodos: Num estudo de coorte histórica foram incluídos doentes com AVCi devido a oclusão de grande vaso submetidos a trombectomia mecânica (TM) que realizaram DTCC nas primeiras 24 horas após início dos sintomas. Recanalização foi definida no angiograma final após TM. A realização do DTCC ocorreu nas primeiras 24 horas após início dos sintomas. Foram colhidas as velocidades na artéria cerebral média (ACM) sintomática e assintomática. As velocidades médias (VM) das ACMs foram quantificadas bem como o rácio da ACM sintomática/assintomática (RaACMs). Realizaram-se TAC Crânio-Encefálicas (CE) às 24 horas após instalação sintomática. Todas as TAC-CE foram revistas por neurorradiologista cego para informação clínica e hemodinâmica e foi considerada TH qualquer hematoma parenquimatoso (PH1 ou PH2). A identificação de preditores independentes precoces de TH tendo em conta os dados do DTCC compreendeu comparações univariáveis e análises multivariáveis.Resultados: Foram incluídos 101 doentes, com idade média de 68.95 (DP, 12.70) anos. Um total de 74 doentes foram submetidos a fibrinólise endovenosa seguida de TM. RaACMs foi estatisticamente superior nos doentes com TH. Em análise multivariável ajustada para a idade, o RaACMs manteve-se um preditor independente de TH (odds ratio, 6.890; intervalo de confiança, 1.332-35.643; P=0.021).Conclusão: O RaACMs avaliado precocemente por DTCC é um preditor independente de TH que pode ser útil na prevenção de deterioração clínica após recanalização arterial por TM. Palavras-chave: acidente vascular cerebral; lesão de reperfusão; trombectomia; ultrassonografia; artéria cerebral média Background and Purpose: Endovascular therapies have achieved high reperfusion rates and excellent clinical outcomes, however it may cause reperfusion injury that can lead to hemorrhagic transformation (HT). Transcranial color-coded sonography (TCCS) is a valid diagnostic tool that can be used to assess cerebrovascular disease. We aimed to determine the predictive value of early TCCS on HT after successful endovascular therapy in acute ischemic stroke due to large vessel occlusion.Methods: In a retrospective cohort study we enrolled consecutive patients with large vessel occlusion strokes submitted to mechanical thrombectomy (MT) that performed TCCS within the first 24 hours after symptoms onset. Recanalization was assessed in the final angiogram after thrombectomy. We measured flow velocities in asymptomatic and symptomatic middle cerebral artery (MCA). Mean flow velocities (MFV) of the MCAs and ratio of the MFV of MCAs (MCAsRo) were calculated. Head CT scan was performed at 24 hours post stroke onset. All scans were reviewed by a neuroradiologist unaware of clinical events and any parenchymal hematoma (PH1 or PH2) was considered HT. Univariate associations and multivariate analyses were used to identify early independent predictors for HT and 3-month mRS among TCCS findings. Results: We included 101 patients; mean age was 68.95 (SD, 12.70) years. A total of 74 (73.30%) patients underwent intravenous thrombolysis followed by MT. MCAsRo was significantly higher in patients with HT. In a multivariate analysis, adjusting for age, MCAsRo remained an independent predictor of HT (odds ratio, 6.890; 95% confidence interval, 1.332-35.643; P=0.021).Conclusion: Early MCAsRo TCCS assessment is an independent predictor of HT and may be useful in promoting preventive interventions. Key-Words: stroke; reperfusion injury; thrombectomy; ultrasonography; middle cerebral artery

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Lopes, Mariana Fernandes Diz. "Microemboli After Successful Thrombectomy Do Not Affect Outcome But Predict New Embolic Events." Dissertação, 2019. https://hdl.handle.net/10216/128932.

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Contexto e Objetivo: Determinar se o microembolismo após trombectomia mecânica se correlaciona com resultados desfavoráveis apesar de uma recanalização bem sucedida. Métodos: Trata-se de um estudo prospetivo multicêntrico com pacientes consecutivos após AVC com oclusão da circulação anterior (artéria carótida interna terminal ou segmento M1/M2 da artéria cerebral média) após trombectomia bem sucedida (grau 2b-3 na escala modificada Treatment in Cerebral Ischemia). Os sinais microembólicos (SME) foram avaliados por Doppler Transcraniano (DTC) durante 30 minutos e dentro de 72 horas após o último momento em que os doentes foram vistos assintomáticos. Os outcomes principais incluíam o valor da escala de Rankin modificada (ERM) aos 90 dias e o volume de enfarte avaliado na TAC cerebral às 24 horas. Adicionalmente, avaliámos outcomes secundários baseados na variação da escala de NIHSS e também a recorrência de AVC, AIT ou embolia sistémica dentro de 90 dias. Resultados: Dentro dos 111 pacientes, foram detetados SME em 43 (39%), com uma taxa mediana de 4/hora (intervalo interquartil 2-12). A ocorrência de SME não foi associada com uma diferença significativa na ERM (regressão ordinal, odds ratio ajustado =1.06 (IC 95% 0.48-2.34), p=0.85) nem na independência funcional (ERM 0-2: odds ratio ajustado =0.52 (IC 95% 0.19-1.39), p=0.19). Os pacientes com e sem SME tinham volumes de enfarte semelhantes (beta ajustado= 11.2 (IC 95% -46.6- +22.9), p=0.51) na TAC às 24 horas. Os SME podem prever novos eventos embólicos (Cox hazard ratio ajustado 6.78 (IC 95% 1.63-27.8), p=0.01). Conclusões: Os sinais microembólicos detetados por DTC após tratamento endovascular de oclusão da circulação anterior não podem prever outcomes clínicos ou radiológicos. No entanto, o microembolismo é um marcador independente de eventos embólicos recorrentes dentro de 90 dias. Background and Purpose: To determine if microemboli after endovascular thrombectomy correlate with unfavorable outcomes despite successful recanalization. Methods: This is a prospective multicenter study of consecutive patients with ischemic stroke and occlusion of anterior circulation vessels (terminal internal carotid or M1/M2 segments of middle cerebral artery) after successful thrombectomy (modified Treatment In Cerebral Ischemia grades 2b-3). Microembolic signals (MES) were assessed by 30-minutes of transcranial Doppler (TCD) monitoring within 72 hours of the last-seen-well time. Major outcomes included modified Rankin scale at 90 days and infarct volume on head CT at 24 hours. We also assessed early outcomes based on NIHSS variation and recurrence of stroke, TIA, or systemic embolism within 90 days. Results: Among 111 patients, MES were detected in 43 (39%), with a median rate of 4 counts/hour (interquartile range 2 - 12). The occurrence of MES was not associated with a significant difference in mRS (ordinal shift analysis, adjusted odds ratio 1.06 (95% CI 0.48 - 2.34), p = 0.85) nor in functional independence (mRS 0 - 2: adjusted odds ratio = 0.52 (95% CI 0.19 - 1.39), p = 0.19). Patients with and without MES had similar infarct volumes (adjusted beta = 11.2 (95% CI - 46.6 - +22.9), p = 0.51) on 24-hour CT. MES did predict new embolic events (adjusted Cox hazard ratio 6.78 (CI 95% 1.63 - 27.8), p=0.01). Conclusions: Microembolic signals detected by TCD following endovascular treatment of anterior circulation occlusions do not predict clinical or radiological outcome. However, such emboli are an independent marker of recurrent embolic events within 90 days.

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Lopes, Mariana Fernandes Diz. "Microemboli After Successful Thrombectomy Do Not Affect Outcome But Predict New Embolic Events." Master's thesis, 2020. https://hdl.handle.net/10216/128932.

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Contexto e Objetivo: Determinar se o microembolismo após trombectomia mecânica se correlaciona com resultados desfavoráveis apesar de uma recanalização bem sucedida. Métodos: Trata-se de um estudo prospetivo multicêntrico com pacientes consecutivos após AVC com oclusão da circulação anterior (artéria carótida interna terminal ou segmento M1/M2 da artéria cerebral média) após trombectomia bem sucedida (grau 2b-3 na escala modificada Treatment in Cerebral Ischemia). Os sinais microembólicos (SME) foram avaliados por Doppler Transcraniano (DTC) durante 30 minutos e dentro de 72 horas após o último momento em que os doentes foram vistos assintomáticos. Os outcomes principais incluíam o valor da escala de Rankin modificada (ERM) aos 90 dias e o volume de enfarte avaliado na TAC cerebral às 24 horas. Adicionalmente, avaliámos outcomes secundários baseados na variação da escala de NIHSS e também a recorrência de AVC, AIT ou embolia sistémica dentro de 90 dias. Resultados: Dentro dos 111 pacientes, foram detetados SME em 43 (39%), com uma taxa mediana de 4/hora (intervalo interquartil 2-12). A ocorrência de SME não foi associada com uma diferença significativa na ERM (regressão ordinal, odds ratio ajustado =1.06 (IC 95% 0.48-2.34), p=0.85) nem na independência funcional (ERM 0-2: odds ratio ajustado =0.52 (IC 95% 0.19-1.39), p=0.19). Os pacientes com e sem SME tinham volumes de enfarte semelhantes (beta ajustado= 11.2 (IC 95% -46.6- +22.9), p=0.51) na TAC às 24 horas. Os SME podem prever novos eventos embólicos (Cox hazard ratio ajustado 6.78 (IC 95% 1.63-27.8), p=0.01). Conclusões: Os sinais microembólicos detetados por DTC após tratamento endovascular de oclusão da circulação anterior não podem prever outcomes clínicos ou radiológicos. No entanto, o microembolismo é um marcador independente de eventos embólicos recorrentes dentro de 90 dias. Background and Purpose: To determine if microemboli after endovascular thrombectomy correlate with unfavorable outcomes despite successful recanalization. Methods: This is a prospective multicenter study of consecutive patients with ischemic stroke and occlusion of anterior circulation vessels (terminal internal carotid or M1/M2 segments of middle cerebral artery) after successful thrombectomy (modified Treatment In Cerebral Ischemia grades 2b-3). Microembolic signals (MES) were assessed by 30-minutes of transcranial Doppler (TCD) monitoring within 72 hours of the last-seen-well time. Major outcomes included modified Rankin scale at 90 days and infarct volume on head CT at 24 hours. We also assessed early outcomes based on NIHSS variation and recurrence of stroke, TIA, or systemic embolism within 90 days. Results: Among 111 patients, MES were detected in 43 (39%), with a median rate of 4 counts/hour (interquartile range 2 - 12). The occurrence of MES was not associated with a significant difference in mRS (ordinal shift analysis, adjusted odds ratio 1.06 (95% CI 0.48 - 2.34), p = 0.85) nor in functional independence (mRS 0 - 2: adjusted odds ratio = 0.52 (95% CI 0.19 - 1.39), p = 0.19). Patients with and without MES had similar infarct volumes (adjusted beta = 11.2 (95% CI - 46.6 - +22.9), p = 0.51) on 24-hour CT. MES did predict new embolic events (adjusted Cox hazard ratio 6.78 (CI 95% 1.63 - 27.8), p=0.01). Conclusions: Microembolic signals detected by TCD following endovascular treatment of anterior circulation occlusions do not predict clinical or radiological outcome. However, such emboli are an independent marker of recurrent embolic events within 90 days.

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Ferreira, Francisca Isabel Barros. "The Impact of Very Short-term Variability of Blood Pressure in Outcome after Successful Thrombectomy." Dissertação, 2019. https://hdl.handle.net/10216/128810.

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Objetivos: Determinar se a variabilidade da pressão arterial a muito curto prazo após trombectomia mecânica eficaz em doentes com acidente vascular cerebral (AVC) isquémico tem um impacto relevante no prognóstico clínico destes doentes. Métodos: Este é um estudo prospectivo com inclusão consecutiva de doentes com AVC isquémico por oclusão de vasos da circulação intracraniana anterior, que realizaram trombectomia mecânica e atingiram recanalização completa (modified Treatment In Cerebral Ischemia graus 2b-3). A variabilidade da pressão arterial foi avaliada por análise espectral das oscilações espontâneas da pressão arterial sistólica no período pós trombectomia. Os outcomes avaliados foram a independência funcional aos 90 dias (escala Rankin modificada 0-2) e a resposta clínica inicial à trombectomia mecânica. Resultados: Foram incluídos 121 doentes. O aumento da variabilidade da pressão arterial a altas frequências (oscilações rápidas) mostrou-se independentemente associado a pior outcome funcional aos 90 dias (unidades normalizadas, odds ratio (OR) = 0.56, 95% intervalo de confiança (CI) 0.35 - 0.88, p=0.01; rácio baixas/altas frequências OR = 0.67, CI 0.46 - 0.98, p=0.04) em análise multivariada. Conclusão: A magnitude das oscilações rápidas da pressão arterial tem um impacto significativo na recuperação neurológica precoce e outcome funcional tardio nos doentes com AVC isquémico após recanalização completa. A variabilidade da pressão arterial a muito curto prazo pode ser avaliada rapidamente durante o período pós-intervencional e contribuir potencialmente para um controlo da pressão arterial mais eficaz nestes doentes, com um impacto prognóstico importante. Background and Purpose: We aim to determine if the very short-term blood pressure variability (BPV) after successful endovascular treatment of acute ischemic stroke has a relevant impact in the clinical outcome. Methods: This is a prospective multicenter study with inclusion of consecutive AIS patients with occlusion of intracranial anterior circulation vessels who achieved successful recanalization (modified Treatment In Cerebral Ischemia grades 2b-3) after thrombectomy. Very short-term BPV was assessed by spectral analysis of spontaneous fluctuations of beat-to-beat systolic blood pressure values recorded by finger plethysmography with Finometer device. Outcomes included independence at 90 days (modified Rankin scale 0-2) and the initial clinical response to mechanical thrombectomy. Results: We included 121 patients. Increased BPV at high frequencies (rapid oscillations) was independently associated with poor functional outcome at 90 days (normalized units, odds ratio (OR) = 0.56, 95% confidence interval (CI) 0.35 - 0.88, p=0.01; low/high frequency ratio OR = 1.38, CI 1.09 - 1.76, p<0.01) and early neurological recovery (normalized units, OR = 0.67, CI 0.46 - 0.98, p=0.04) in multivariate analysis. Conclusions: The magnitude of rapid oscillations of blood pressure has a significant impact in early neurological recovery and late functional outcome of ischemic stroke patients after successful recanalization. Very short-term BPV can be assessed quickly throughout the post intervention period and potentially contribute to a more efficient blood pressure control in AIS patients submitted to endovascular treatment.

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Ferreira, Francisca Isabel Barros. "The Impact of Very Short-term Variability of Blood Pressure in Outcome after Successful Thrombectomy." Master's thesis, 2020. https://hdl.handle.net/10216/128810.

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Objetivos: Determinar se a variabilidade da pressão arterial a muito curto prazo após trombectomia mecânica eficaz em doentes com acidente vascular cerebral (AVC) isquémico tem um impacto relevante no prognóstico clínico destes doentes. Métodos: Este é um estudo prospectivo com inclusão consecutiva de doentes com AVC isquémico por oclusão de vasos da circulação intracraniana anterior, que realizaram trombectomia mecânica e atingiram recanalização completa (modified Treatment In Cerebral Ischemia graus 2b-3). A variabilidade da pressão arterial foi avaliada por análise espectral das oscilações espontâneas da pressão arterial sistólica no período pós trombectomia. Os outcomes avaliados foram a independência funcional aos 90 dias (escala Rankin modificada 0-2) e a resposta clínica inicial à trombectomia mecânica. Resultados: Foram incluídos 121 doentes. O aumento da variabilidade da pressão arterial a altas frequências (oscilações rápidas) mostrou-se independentemente associado a pior outcome funcional aos 90 dias (unidades normalizadas, odds ratio (OR) = 0.56, 95% intervalo de confiança (CI) 0.35 - 0.88, p=0.01; rácio baixas/altas frequências OR = 0.67, CI 0.46 - 0.98, p=0.04) em análise multivariada. Conclusão: A magnitude das oscilações rápidas da pressão arterial tem um impacto significativo na recuperação neurológica precoce e outcome funcional tardio nos doentes com AVC isquémico após recanalização completa. A variabilidade da pressão arterial a muito curto prazo pode ser avaliada rapidamente durante o período pós-intervencional e contribuir potencialmente para um controlo da pressão arterial mais eficaz nestes doentes, com um impacto prognóstico importante. Background and Purpose: We aim to determine if the very short-term blood pressure variability (BPV) after successful endovascular treatment of acute ischemic stroke has a relevant impact in the clinical outcome. Methods: This is a prospective multicenter study with inclusion of consecutive AIS patients with occlusion of intracranial anterior circulation vessels who achieved successful recanalization (modified Treatment In Cerebral Ischemia grades 2b-3) after thrombectomy. Very short-term BPV was assessed by spectral analysis of spontaneous fluctuations of beat-to-beat systolic blood pressure values recorded by finger plethysmography with Finometer device. Outcomes included independence at 90 days (modified Rankin scale 0-2) and the initial clinical response to mechanical thrombectomy. Results: We included 121 patients. Increased BPV at high frequencies (rapid oscillations) was independently associated with poor functional outcome at 90 days (normalized units, odds ratio (OR) = 0.56, 95% confidence interval (CI) 0.35 - 0.88, p=0.01; low/high frequency ratio OR = 1.38, CI 1.09 - 1.76, p<0.01) and early neurological recovery (normalized units, OR = 0.67, CI 0.46 - 0.98, p=0.04) in multivariate analysis. Conclusions: The magnitude of rapid oscillations of blood pressure has a significant impact in early neurological recovery and late functional outcome of ischemic stroke patients after successful recanalization. Very short-term BPV can be assessed quickly throughout the post intervention period and potentially contribute to a more efficient blood pressure control in AIS patients submitted to endovascular treatment.

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LLien, Mei-Hua, and 練美華. "Cost Effectiveness Analysis of Thrombolysis For Therapy and Intraarterial Thrombectomy Acute Ischemic Stroke:Systematic Literature Rreview and Meta-Analysis." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ev5vbp.

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碩士 高雄醫學大學 醫務管理暨醫療資訊學系碩士在職專班 106 There is no consistent conclusion regarding whether Intra-arterial embolectomy (IAT) is better than Intravenous thrombolytic therapy (IV r-tPA). Therefore, this study is to examine the differences in cost, effectiveness and cost-effectiveness between IAT and IB r-tPA. Materials and methods This study was conducted using systemic review and meta-analysis.Different combinations of key words were used in searching eight databases. After being through PRISMA for stages and flow diagram, 18 articles were selected and further analyzed using CMAIII meta-analysis software. Meta-analysis tools used included I2, Q-value, p value, funnel plot, fail-safe number, summary effect size and forest plot. Results The difference of cost and effectiveness between IAT and IV r-tPA were analyzed using meta-analysis whereas incremental cost-effectiveness(ICER)was presented using descriptive statistics. The results sowed that the cost of IAT is higher than that of IV r-tPA. In terms of effectiveness, more patients in IAT group after 90 day primary efficacy end point modified Rankin Scale score (mRS) in comparison to IV r-tPA group. There was no difference in other complications, including mortality rate, Intracranial hemorrhage rate. Furthermore, ICER of IAT compared with IV r-tPA was considered very cost-effective. Conclusions Both IAT and IV r-tPA were deemed cost-effective.IAT was more expensive than IAT. Nevertheless, none of those studies were carried out in Taiwan hence equivalent studies on Taiwanese is expectel in order to provide our people better options.

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LI, PEI-XUAN, and 李佩軒. "Predicting Modified Rankin Scale of Stroke Patients after Intra-arterial thrombectomy using machine learning with models correcting Imbalanced Small Data Sets." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/43f53r.

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碩士 國立臺北科技大學 資訊與財金管理系 107 With the rapid development of information, artificial intelligence and machine learning have begun to occupy a central position in emerging technologies. Data analysis has been widely used in various fields, and it is inevitable to encounter unbalanced small data with severely skewed categories, so that classifier performance falling may also cause overfitting. In this study, Borderline-SMOTE and SMOTE were used to achieve data balance, and proposed a model for solving imbalanced small data. SMOTE random oversampling to increase the number of samples can prevent overfitting and improve the performance of the classifier. However, the process of synthesizing new samples does not fully consider the information of a few neighboring samples. It often leads to serious sample overlapping, and Borderline-SMOTE considers the distribution of data and eliminates noise instance and safe instance so that the classifier can pay more attention to the nearest neighbor sample information of a few types of sample ,which can strengthen the minority sample and most sample. The boundary is different from SMOTE in that it does not consider the distribution of data. Therefore, this model improved the Borderline-SMOTE and combined with the generative adversarial network, named GAN-BLSMOTE. The study sample used 34 patients’s data from the Medical Center between 2016 and 2018 to perform intra-arterial thrombectomy. Using computer tomography to check the patients who have hemorrhage or not, and establish different machine learning models, including decision tree algorithm, random forest algorithm, support vector machine regression in stroke scale score prediction model, the accuracy of the balanced data method GAN-BLSMOTE can be as high as 94%, providing a method for doctors to diagnose the severity of stroke, as a reference for medical decision-making, solving the problem of medically imbalanced small data. And compared different data sets and imbalance ratios

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Yung-Ming and 張永明. "Analysis of AngioJet Thrombectomy on Myocardial Perfusion and Six-month Survival for Patients with Acute ST-elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/84058014995863347486.

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碩士 中山醫學大學 醫學研究所 100 Objective: Patients with acute ST-elevation myocardial infarction may have persistent impairment of microvascular blood flow even after successful primary percutaneous coronary intervention ( PCI ). Distal embolization is a possible mechanism of microvascular dysfunction and impaired myocardial perfusion. There has been increasing interest in adjunctive mechanical thrombectomy to improve outcomes in primary PCI. The aim of the present report is to study the role of AngioJet thrombectomy in primary PCI for acute ST-elevation myocardial infarction . Method and Materials: This is a retrospective cohort study. Patients presented with acute ST-elevation myocardial infarction and received primary PCI in ChangHua Christian Hospital between Jan. 2003 and Oct. 2007 were enrolled. Totally 313 patients were included, 219 patients are in the AngioJet group and the other 94 patients are in the control group. The baseline characteristics, angiographic findings and 6-months survival in these two groups were recorded. Results: Patients in the AngioJet group have more male, cardiac enzymes elevation and angiographically visible thrombus. The angiographic findings showed that 94.1% in the AngioJet group have TIMI 3 flow after primary PCI, but only 80.9% in the control group have the same TIMI 3 flow. Besides, we also find the similar MBG flow between two groups. MBG 3 flow was achieved in 56.2% of the AngioJet group and 39% of the control group. The 6-months survival did not show significant difference between groups ( 93.2% versus 91.5% ). Conclusion and Suggestion: AngioJet thrombectomy in primary PCI for patients with acute ST-elevation MI can improve TIMI flow and MBG flow. But it remains to be established weather the device improves outcomes. The current evidence does not support the routine use of the AngioJet system in primary PCI. But in selected patients with large burden of thrombus, it still can provide clinical benefit as an adjunct to primary PCI.

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Aires, Fátima Aurora Lima. "TC perfusão na seleção de doentes com avc agudo candidatos a terapêutica de revascularização endovascular." Master's thesis, 2017. http://hdl.handle.net/10316/82623.

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Trabalho de Projeto do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina Introdução: Persistem dúvidas sobre a possibilidade de a tomografia computorizada com perfusão (TCP) adicionar informação clinicamente relevante à obtida na tomografia computorizada crânio-encefálica não contrastada (TCNC) e na angiotomografia computorizada (TCA), na seleção de doentes com acidente vascular cerebral isquémico (AVCi) por oclusão de artéria intracraniana de grande calibre candidatos a trombectomia. O objetivo deste estudo é avaliar a importância da utilização da TCP neste grupo específico de doentes.Materiais e Métodos: Neste estudo observacional, de coorte histórica, foram incluídos todos os doentes avaliados no contexto de Via Verde do AVC e admitidos na Unidade de UAVC/Serviço de Neurologia do Centro Hospitalar e Universitário de Coimbra (CHUC), com diagnóstico de AVCi e documentação, por TCA, de oclusão de artéria intracraniana de grande calibre da circulação anterior (artéria carótida interna e/ou segmento M1 e/ou M2 proximal da artéria cerebral média) no período compreendido entre 01 de janeiro de 2015 e 31 de dezembro de 2015. Foram recolhidos e analisados dados clínicos, demográficos e imagiológicos, tempos de atuação, eficácia do tratamento e prognóstico aos três meses. Consideraram-se dois grupos: um em que foi realizada TCP e outro em que este exame não foi efectuado. Nos doentes com TC multimodal completa foi avaliada, com ocultação de decisão terapêutica e resultado clínico, a potencialidade do estudo por TCP modificar a seleção de doentes fundamentada em TCNC e TCA.Resultados: Dos 94 doentes incluídos, 68 (72.3%) realizaram TCP e 26 (27.7%) não realizaram TCP. Os dois grupos mostraram-se homogéneos em relação às características demográficas e a presença de fatores de risco e comorbilidades foi moderada em ambos. Na TCNC inicial, o grupo de doentes que não realizou estudo de perfusão apresentou valores de ASPECTS superiores – 9.0 vs 8.0. Os tempos de atuação foram semelhantes para os dois grupos, exceto no tempo TC-punção com uma mediana de 79.5 minutos (Aiq 46.25) para o grupo de doentes com TCP e 60.0 minutos (Aiq 31.5) para o grupo de doentes sem TCP. Não encontrámos diferenças estatisticamente significativas na taxa de recanalização, 77.9% e 61.5% para o grupo com TCP e sem TCP, respetivamente, (p>0.05), ou na transformação hemorrágica (1.5% e 0.0% para o grupo com TCP e sem TCP, respetivamente, p>0.05). Do mesmo modo, a realização da TCP não demonstrou ser preditor independente de prognóstico aos três meses – OR 0.446 (p>0.05). No estudo de inclusão da TCP e potencial modificação da decisão clínica, a adição do estudo de perfusão não alterou a decisão terapêutica baseada na TCNC e TCA, no que se refere à terapêutica endovascular dos dois grupos de investigadores (83.8% e 77.9%, concordância elevada na equipa um – k = 0.673, e moderada na equipa dois - k = 0.434). Além disto, a concordância entre as equipas foi moderada-elevada com a adição de TCP e fraca sem TCP, k = 0.510 e k = 0.397, respetivamente. Conclusão: Na seleção de doentes com AVCi, a realização de TCP associa-se ao alargamento dos tempos de atuação para terapêutica endovascular sem benefício imediato - taxa de recanalização ou transformação hemorrágica - ou melhoria do prognóstico funcional aos três meses. O estudo adicional por TCP parece não modificar a decisão clínica inicial após TCNC e TCA, mas pode contribuir para a homogeneização da decisão clínica. Introduction: Doubts remain about whether computed tomography with perfusion (CTP) adds clinically relevant information to that obtained in noncontrast computed tomography (NCCT) and computerized angiotomography (CTA) in the selection of patients with acute ischemic stroke (AIS) due to occlusion of large intracranial artery and candidates for thrombectomy. The purpose of this work is to evaluate the usefulness of CTP in this specific group of patients.Materials and Methods: In this historical cohort observational study, we included patients who were evaluated in the context AIS and admitted to stroke unit or neurology ward of University Hospital with a diagnosis of stroke and CTA documentation of occlusion of a large intracranial arteries in the anterior circulation (internal carotid artery and/or M1 and/or M2 proximal segments of the middle cerebral artery) during the period from January 1, 2015 to December 31, 2015. Clinical, demographic and imaging data were collected and analyzed, as performance times, treatment efficacy and functional prognosis at three months. Two groups were considered, one that performed CTP and other that did not perform CTP. Evaluation of the potentiality of CTP modify the selection of patients based on NCCT and CTA was assessed in patients with complete multimodal CT, with the concealment of therapeutic decision and clinical result.Results: In this study, 94 patients were included. Of those 68 (72.3%) performed CTP and 26 (27.7%) did not perform CTP. These were the two study groups, that were homogeneous in relation to the demographic characteristics and the presence of risk factors and comorbidities (moderate in both).In the initial NCCT, the group of patients who did not perform perfusion study had higher ASPECTS values - 9.0 vs 8.0. Performance times were similar for both groups, except for the CT to groin puncture time with a median of 79.5 minutes (IQR 46.25) for the CTP patient group and 60.0 minutes (IQR 31.5) for the group of patients without CTP. We did not find statistically significant differences in the recanalization rate, 77.9% and 61.5% for the group with TCP and without TCP, respectively (p> 0.05), or in the hemorrhagic transformation (with 1.5% and 0.0% for the group with CTP and without CTP, respectively (p> 0.05)) - as well as CTP imaging did not prove to be an independent predictor of prognosis at three months - OR 0.446 (p> 0.05). In the study of inclusion of CTP and potential modification of the clinical decision, perfusion study did not change the therapeutic decision based on the NCCT and CTA, regarding the endovascular treatment, of the two groups of researchers (83.8% and 77.9%, high agreement in team one - k = 0.673, and moderate in team two - k = 0.434). Furthermore, agreement between the teams was moderate-high with the addition of CTP and weak without CTP, k = 0.510 and k = 0.397, respectively.Conclusion: In AIS patients, CTP is associated with longer periods of time to endovascular therapy without immediate benefit – recanalization rate or hemorrhagic transformation – or better functional prognosis at three months.CTP study does not seem change the initial orientation after CT and CTA, but it may contribute to a homogenization of the clinical decision.

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Tsogkas, Ioannis. "Wert des CBV-ASPECTS im Vergleich zum CTA-ASPECTS bei Patienten mit akutem ischämischem Schlaganfall." Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1503-0.

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Monteiro, João Pedro Mendes. "Prognostic value of cerebral perfusion CT on stroke: correlation between the size of stoke within the territory of the Middle Cerebral Artery and the area of hypoperfusion on patients with acute stage stroke without intra-arterial thrombectomy." Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/76502.

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Monteiro, João Pedro Mendes. "Prognostic value of cerebral perfusion CT on stroke: correlation between the size of stoke within the territory of the Middle Cerebral Artery and the area of hypoperfusion on patients with acute stage stroke without intra-arterial thrombectomy." Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/76502.

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Reinhardt, Lars. "Anwendbarkeit des Alberta Stroke Program Early CT Score (ASPECTS) anhand multimodaler CT-Bildgebung in der Schlaganfallfrühdiagnostik und dessen Fähigkeit zur Vorhersage des klinischen Behandlungsergebnisses für Patienten, welche durch Thrombusextraktion durch Aspiration behandelt werden." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-002B-7CDF-2.

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Der ischämische Schlaganfall ist ein ernstzunehmendes Ereignis, welches rascher Rekanalisationstherapie bedarf. Hierfür stehen mehrere Therapieansätze zur Verfügung. Bildgebungsgestützte Patientenselektion zur individuell geeigneten Therapie kann das abschließende klinische Behandlungsergebnis des einzelnen Patienten maßgeblich verbessern. Der Alberta Stroke Program Early CT Score (ASPECTS), eine einfach und schnell anwendbare 10-Punkte-Skala zur Auswertung von Schädel-CT-Untersuchungen, wurde bereits als hilfreicher Prädiktor für das klinische Behandlungsergebnis nach erfolgreicher thrombolytischer Therapie identifiziert. Ein Nachteil der nativen Schädel-CT ist, dass der Infarktkern erst mit mehreren Stunden Verzögerung erkennbar wird. Das aktuelle Ausmaß des Infarktkerns kann durch Bestimmung des zerebralen Blutvolumens (CBV) anhand von Perfusions-CT-Untersuchungen schneller ermittelt werden. Diese Studie analysiert retrospektiv multimodale CT-Bildgebung einer Patientenkohorte von 51 Patienten mit akutem ischämischen Schlaganfall aufgrund eines Verschlusses im M1-Segment der Arteria cerebri media bezüglich des Behandlungsergebnisses nach endovaskulärer Therapie. Die CT-Daten wurden mit kommerzieller Computersoftware nachverarbeitet. Zwei erfahrene Neuroradiologen werteten getrennt voneinander Nativ- und Perfusions-CT-Daten mithilfe des ASPECTS aus. Die Befunde der Patientengruppe mit schlechtem klinischen Behandlungsergebnis wurden mit denen der Gruppe mit gutem Ergebnis verglichen. Variablen, welche statistisch signifikante Unterschiede aufwiesen, wurden daraufhin untersucht. Zwischen den Ergebnissen der Rekanalisationstherapie, den Zeitintervallen oder den nativen CT-ASPECTS-Ergebnissen beider Gruppen bestand kein signifikanter Unterschied. Signifikant unterschieden sich die Gruppen im Hinblick auf das Patientenalter. Die übrigen Basischarakteristika der beiden Patientengruppen unterschieden sich nicht signifikant. Es ergaben sich weiterhin signifikante Unterschiede im Bezug auf den ASPECTS für zerebralen Blutfluss (CBF-ASPECTS) und die Differenz zwischen ASPECTS für zerebrales Blutvolumen (CBV-ASPECTS) und CBF-ASPECTS [Δ(CBV - CBF)-ASPECTS]. Für CBV-ASPECTS > 7 konnte die höchste Sensitivität (84 %) und Spezifität (79 %) zur Voraussage eines guten klinischen Behandlungsergebnisses ermittelt werden. Diese Studie zeigt, dass durch ASPECTS ausgewertete CT-Perfusionsparameter eine optimale Voraussagekraft für das klinische Behandlungsergebnis nach erfolgreicher Rekanalisationstherapie besitzen und diese sensitiver und spezifischer als der native CT-ASPECTS sind. Der ASPECTS erlaubt einen einfachen und schnellen quantitativen Überblick über die tatsächliche aktuelle Situation des einzelnen Patienten. Die Berücksichtigung dieser Parameter bei Therapieentscheidungen könnte helfen, Patienten der geeigneten Therapie zuzuführen und die Anzahl vergeblicher Rekanalisationsbehandlungen zu reduzieren.

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Antunes, Edgar Coelho. "AVC isquémico agudo em Portugal: a relação entre o volume e os resultados em trombectomia mecânica nos hospitais públicos portugueses em 2017." Master's thesis, 2020. http://hdl.handle.net/10362/119984.

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RESUMO - Enquadramento: Inúmeros estudos realizados desde há vários anos reforçam a premissa de que o volume hospitalar influência os resultados em saúde. Apesar de se verificar em muitos procedimentos, esta premissa não é válida para todos os procedimentos analisados, sendo um tema até à data parco em estudos realizados em Portugal. O objetivo da corrente investigação foi de avaliar a relação entre o volume hospitalar de trombectomias mecânicas e os resultados em saúde nos hospitais públicos de Portugal continental no ano de 2017, particularmente da mortalidade intra-hospitalar, a presença de pelo menos uma complicação e a duração do internamento. Metodologia: Foi realizado um estudo observacional, transversal, analítico com recolha de informação retrospetiva através da base de dados de morbilidade hospitalar cedida pela Administração Central do Sistema de Saúde (ACSS). Selecionaram-se todos os episódios correspondentes à presença de trombectomia mecânica e aplicados critérios de exclusão. Os hospitais abrangidos por este estudo foram categorizados tendo em conta o volume anual de trombectomias mecânicas. Resultados: Analisaram-se 1535 episódios de utentes submetidos a trombectomia mecânica em 12 hospitais públicos portugueses. Após a análise bivariável e respetivo ajustamento pelo risco, apenas a duração do internamento é influenciada pelo volume hospitalar, sendo que com o aumento do volume hospitalar o tempo de internamento diminui. Conclusão: Apesar de não ser um tema novo, não existem estudos realizados em Portugal avaliando a existência de uma relação entre o volume hospitalar de trombectomias mecânicas e os resultados em saúde. Sendo importante não retirar conclusões precipitadas face aos resultados obtidos neste tipo de estudos, sem antes considerar todos os fatores que podem fazer variar os resultados em saúde avaliados. É imperativo desenvolver o tema não só para o caso da trombectomia mecânica, mas também para outros procedimentos que podem beneficiar deste tipo de análise. ABSTRACT - Background: Countless studies carried out for several years reinforce the premise that hospital volume influences health outcome. Despite this relationship being found in many procedures, this premise is not valid for all the analyzed procedures, being a scarce topic in studies carried out in Portugal. The objective of the current investigation was to asess the relationship between the hospital volume of mechanical thrombectomies and the health outcomes in mainland Portugal in 2017, particularly in-hospital mortality, the presence of at least one complication and the duration of internment. Methods: An observational, cross-sectional, analytical study was carried out with the collection of retrospective information through the hospital morbidity database provided by the Central Administration of the Health System (ACSS). All episodes corresponding to the presence of mechanical thrombectomy were selected and exclusion criteria were applied. The hospitals covered by this study were categorized taking into account the annual volume of mechanical thrombectomies. Results: 1535 episodes of patients undergoing mechanical thrombectomy were analyzed in 12 Portuguese public hospitals. After the bivariate analysis and respective risk adjustment, only the length of hospital stay is influenced by the hospital volume, and with the increase in hospital volume, the length of hospital stay decreases. Conclusion: Although not a new topic, there are no studies carried out in Portugal evaluating the existence of a relationship between the hospital volume of mechanical thrombectomies and health outcomes. It is important not to jump to conclusions in view of the results obtained in this type of studies, without first considering all the factors that may vary the health outcomes evaluated. It is imperative to develop the theme not only for the case of mechanical thrombectomy, but also for other procedures that can benefit from this type of analysis.

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Dissertations / Theses on the topic 'Thrombectomie'

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