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Background and Aims: Besides the crucial role in the treatment of acute ischemic stroke (AIS), mechanical thrombectomy represents a unique opportunity for researchers to study the retrieved clots, with the possibility of unveiling biological patterns linked to stroke pathophysiology and etiology. We aimed to develop a shotgun proteomic approach to study and compare the proteome of formalin-fixed paraffin-embedded (FFPE) cardioembolic and large artery atherosclerotic (LAA) clots. Methods: We used 16 cardioembolic and 15 LAA FFPE thrombi from 31 AIS patients. The thrombus proteome was analyzed by label-free quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS). MaxQuant v1.5.2.8 and Perseus v.1.6.15.0 were used for bioinformatics analysis. Protein classes were identified using the PANTHER database and the STRING database was used to predict protein interactions. Results: We identified 1,581 protein groups as part of the AIS thrombus proteome. Fourteen significantly differentially abundant proteins across the two etiologies were identified. Four proteins involved in the ubiquitin-proteasome pathway, blood coagulation or plasminogen activating cascade were identified as significantly abundant in LAA clots. Ten proteins involved in the ubiquitin proteasome-pathway, cytoskeletal remodeling of platelets, platelet adhesion or blood coagulation were identified as significantly abundant in cardioembolic clots. Conclusion: Our results outlined a set of 14 proteins for a proof-of-principle characterization of cardioembolic and LAA FFPE clots, advancing the proteome profile of AIS human thrombi and understanding the pathophysiology of ischemic stroke. Copyright © 2022 Rossi, Mereuta, Barbachan e Silva, Molina Gil, Douglas, Pandit, Gilvarry, McCarthy, O'Connell, Tierney, Psychogios, Tsivgoulis, Szikora, Tatlisumak, Rentzos, Thornton, Ó Broin and Doyle.

Background and purpose: There is still much debate whether bridging-therapy [intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT)] might be beneficial compared to MT alone. We investigated the effect of IVT on size and histological composition of the clots retrieved from patients undergoing bridging-therapy or MT alone. Methods: We collected mechanically extracted thrombi from 1000 acute ischemic stroke (AIS) patients included in RESTORE registry. Patients were grouped according to the administration (or not) of IVT before thrombectomy. Gross photos of each clot were taken and Extracted Clot Area (ECA) was measured using ImageJ software. Martius Scarlett Blue stain was used to characterize the main histological clot components [red blood cells (RBCs), fibrin (FIB), platelets/other (PTL)] and Orbit Image Analysis was used for quantification. Additionally, we calculated the area of each main component by multiplying the component percent by ECA. Chi-squared and Kruskal–Wallis tests were used for statistical analysis. Results: 451 patients (45%) were treated with bridging-therapy while 549 (55%) underwent MT alone. When considering only percent histological composition, we did not find any difference in RBC% (P = 0.895), FIB% (P = 0.458) and PTL% (P = 0.905). However, bridging-therapy clots were significantly smaller than MT-alone clots [32.7 (14.8–64.9) versus 36.8 (20.1–79.8) mm2, N = 1000, H1 = 7.679, P = 0.006*]. A further analysis expressing components per clot area showed that clots retrieved from bridging-therapy cases contained less RBCs [13.25 (4.29–32.06) versus 14.97 (4.93–39.80) mm2, H1 = 3.637, P = 0.056] and significantly less fibrin [9.10 (4.62–17.98) versus 10.54 (5.57–22.48) mm2, H1 = 7.920, P = 0.005*] and platelets/other [5.04 (2.26–11.32) versus 6.54 (2.94–13.79) mm2, H1 = 9.380, P = 0.002*] than MT-alone clots. Conclusions: Our results suggest that previous IVT administration significantly reduces thrombus size, proportionally releasing all the main histological components. © 2021, The Author(s).

Objectives: There is a paucity of knowledge in the literature relating to the extent of clot burden and stroke etiology. In this study, we measured the Extracted Clot Area (ECA) retrieved during endovascular treatment (EVT) and investigated relationships with suspected etiology, administration of intravenous thrombolysis and recanalization. Materials and Methods: As part of the multi-institutional RESTORE registry, the ECA retrieved during mechanical thrombectomy was quantified using ImageJ. The effect of stroke etiology (Large-artery atherosclerosis (LAA), Cardioembolism, Cryptogenic and other) and recombinant tissue plasminogen activator (rtPA) on ECA and recanalization outcome (mTICI) was assessed. Successful recanalization was described as mTICI 2c-3. Results: A total of 550 patients who underwent EVT with any clot retrieved were included in the study. The ECA was significantly larger in the LAA group compared to all other etiologies. The average ECA size of each etiology was; LAA=109 mm2, Cardioembolic=52 mm2, Cryptogenic=47 mm2 and Other=52 mm2 (p=0.014*). LAA patients also had a significantly poorer rate of successful recanalization (mTICI 2c-3) compared to all other etiologies (p=0.003*). The administration of tPA was associated with a smaller ECA in both LAA (p=0.007*) and cardioembolic (p=0.035*) groups. Conclusion: The ECA of LAA clots was double the size of all other etiologies and this is associated with a lower rate of successful recanalization in LAA stroke subtype. rtPA administration prior to thrombectomy was associated with reduced ECA in LAA and CE clots. © 2020 The Authors

International audience; ABSTRACT: After five positive randomized controlled trials showed benefit of mechanical thrombectomy in the management of acute ischemic stroke with emergent large-vessel occlusion, a multi-society meeting was organized during the 17th Congress of the World Federation of Interventional and Therapeutic Neuroradiology in October 2017 in Budapest, Hungary. This multi-society meeting was dedicated to establish standards of practice in acute ischemic stroke intervention aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing medical thrombectomy for acute ischemic stroke, but not for other neurovascular diseases (level 2 centers). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (level 3 centers). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The multi-society group provides recommendations and a framework for the development of medical thrombectomy services worldwide.; RÉSUMÉ : Les normes de pratique recommandées à l’échelle internationale lors d’interventions consécutives à un accident ischémique cérébral aigu . En octobre 2017, à Budapest, une rencontre pluridisciplinaire de spécialistes s’est organisée dans le cadre du 17 e congrès de la World Federation of Interventional and Therapeutic Neuroradiology . Cette rencontre portait sur l’établissement de normes relatives aux interventions consécutives à des accidents ischémiques aigus. Elle a eu lieu, précisons-le, après que cinq essais randomisés contrôlés (ERC) ont montré les avantages de la thrombectomie mécanique dans la prise en charge de patients victimes d’un accident ischémique cérébral aigu montrant des signes naissants d’occlusion des plus gros vaisseaux sanguins. Les normes dont il a été alors question visaient aussi à atteindre un consensus quant aux exigences minimales auxquelles devaient se conformer les établissements de santé offrant la thrombectomie mécanique. Dans l’idéal, tous les patients devraient être traités dans un établissement offrant un éventail complet de soins neuro-endovasculaires (de niveau 1). Toutefois, en raison de l’éloignement géographique, quelques patients demeurent incapables de se rendre dans un tel établissement dans des délais raisonnables. Dans cette optique, le groupe réuni à Budapest a défini de façon particulière des recommandations définissant les aspects permettant aux autres établissements (de niveau 2) d’organiser en amont des soins en thrombectomie destinés à des patients victimes d’accidents ischémiques cérébraux aigus mais pas d’autres maladies neurovasculaires. Enfin, d’autres établissements (de niveau 3) pourront compter sur une unité de traitement des AVC, notamment au moyen de la thrombolyse intraveineuse; toutefois, ils ne pourront offrir aucune autre thérapie endovasculaire. Réunis, l’ensemble de ces établissements de niveaux 1, 2 et 3 constitue un réseau complet de soins destinés aux patients victimes d’un AVC. Le groupe multidisciplinaire réuni lors de cette rencontre a ainsi élaboré des recommandations et un cadre de référence visant le développement de la thrombectomie dans le monde entier.

After the five positive randomized controlled trials showing the benefit of mechanical thrombectomy (MT) in the management of acute ischemic stroke (AIS) with emergent large vessel occlusion (ELVO), a multisociety meeting was organized during the 16th Congress of the World Federation of Interventional and Therapeutic Neuroradiology (WFITN), October 2015, Gold Coast (Australia). This meeting was dedicated to the training of physicians performing MT, and recommendations were published thereafter in multiple scientific journals.1 The same group of scientific societies decided to organize a similar meeting during the 17th WFITN Congress, October 2017, Budapest (Hungary). This multisociety meeting was dedicated to standards of practice in acute ischemic stroke intervention (AISI), aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing MT for AIS, but not for other neurovascular diseases (a level 2 center). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (a level 3 center). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The requirements for these centers are summarized in table 1. View this table: Table 1 General summary of capabilities of level 1, 2, and 3 centers Due to the relatively short time elapsed since the evidence in favor of MT has been published, some organizational aspects still require scientific validation. However, considering the extremely fast growth of such activities around the world, the multisociety group considered it timely and rational to set-up recommendations and a framework for …

Limited data exist on clot composition and detailed characteristics of arterial thrombi associated with large vessel occlusion in acute ischemic stroke. Advances in endovascular thrombectomy and related imaging modalities have created a unique opportunity to analyze thrombi removed from cerebral arteries. Insights into thrombus composition, etiology, physical properties and neurovascular interactions may lead to future advancements in acute ischemic stroke treatment and improved clinical outcomes. Advances in imaging techniques may enhance clot characterization and inform therapeutic decision-making prior to treatment and reveal stroke etiology to guide secondary prevention. Current imaging techniques can provide some information about thrombi, but there remains much to evaluate about relationships that may exist among thrombus composition, occlusion characteristics and treatment outcomes. Improved pathophysiological characterization of clot types, their properties and how these properties change over time, together with clinical correlates from ongoing studies, may facilitate revascularization with thrombolysis and thrombectomy. Interdisciplinary approaches covering clinical, engineering and scientific aspects of thrombus research will be key to advancing the understanding of thrombi and improving acute ischemic stroke therapy. This consensus statement integrates recent research on clots and thrombi retrieved from cerebral arteries and provides a rationale for further analyses, including current opportunities and limitations.

Item does not contain fulltext BACKGROUND AND PURPOSE: Incomplete occlusion and recanalization of large and wide-neck brain aneurysms treated by endovascular therapy remains a challenge. We present preliminary clinical and angiographic results of an experimentally optimized Surpass flow diverter for treatment of intracranial aneurysms in a prospective, multicenter, nonrandomized, single-arm study. MATERIALS AND METHODS: At 24 centers, 165 patients with 190 intracranial aneurysms of the anterior and posterior circulations were enrolled. The primary efficacy end point was the percentage of intracranial aneurysms with 100% occlusion on 6-month DSA. The primary safety end point was neurologic death and any stroke through a minimum follow-up of 6 months. RESULTS: Successful flow-diverter delivery was achieved in 161 patients with 186 aneurysms (98%); the mean number of devices used per aneurysm was 1.05. Clinical follow-up (median, 6 months) of 150 patients (93.2%), showed that the primary safety end point occurred in 18 subjects. Permanent neurologic morbidity and mortality were 6% and 2.7%, respectively. Morbidity occurred in 4% and 7.4% of patients treated for aneurysms of the anterior and posterior circulation, respectively. Neurologic death during follow-up was observed in 1.6% and 7.4% of patients with treated intracranial aneurysms of the anterior and posterior circulation, respectively. Ischemic stroke at 30 days or SAH at >7 days occurred. New or worsening cranial nerve deficit was observed in 2.7%. Follow-up angiography available in 158 (86.8%) intracranial aneurysms showed 100% occlusion in 75%. CONCLUSIONS: Clinical outcomes of the Surpass flow diverter in the treatment of intracranial aneurysms show a safety profile that is comparable with that of stent-assisted coil embolization. Angiographic results showed a high rate of intracranial aneurysm occlusion.

International audience; Background and purpose Flow disruption with the WEB-DL device has been used safely for the treatment of wide-necked bifurcation aneurysms but the stability of aneurysm occlusion after this treatment is unknown. This retrospective multicenter European study analyzed short- and midterm data in patients treated with WEB-DL.Methods Twelve European neurointerventional centers participated to the study. Clinical data, pre- and post-operative, short-, and midterm images were collected. An experienced interventional neuroradiologist independently analyzed images. Aneurysm occlusion was classified in 4 grades: complete occlusion, opacification of the proximal recess of the device, neck remnant, and aneurysm remnant.Results Forty-five patients (34 females and 11 males) aged 35 to 74 years (mean: 56.3 +/- 9.6 years) harbouring 45 aneurysms treated with the WEB device were included. Aneurysm locations were middle cerebral artery in 26 patients, posterior circulation in 13, anterior communicating artery in 5, and internal carotid artery terminus in 1. Forty-two aneurysms were unruptured. Good clinical outcome (mRS < 2) was observed in 93.3% of patients. Adequate occlusion (Complete occlusion, opacification of the proximal recess, or neck remnant) was observed in 30/37 patients (81.1%) in short-term follow-up (median 6 months) and in 26/29 patients (89.7%) in midterm follow-up (median 13 months). Worsening of aneurysm occlusion was observed in 2/28 patients (7.1%) in midterm follow-up.Conclusions The results suggest WEB treatment of wide-neck bifurcation aneurysms offers stable occlusion in aneurysms that are usually unstable. Additionally, our data show that opacification of the WEB recess can be delineated from true neck or aneurysm remnant.