Long-term outcome of endovascular treatment for indirect carotid-cavernous fistulas.

OBJECTIVE: Endovascular treatment (EVT) is the primary approach used to treat indirect carotid-cavernous fistulas (CCFs). In this study, the authors evaluated the immediate and long-term efficacy and safety of different endovascular techniques for indirect CCFs. METHODS: The databases of two endovascular centers were retrospectively reviewed to collect the patients with indirect CCFs treated using endovascular techniques between 2013 and 2023. Demographics, clinical presentation, CCF features, EVT characteristics, and clinical and radiological outcomes were evaluated and analyzed. The analysis was performed to compare the clinical and radiological data between different endovascular approaches and different embolic materials. RESULTS: Ninety-eight patients were included in the study. EVT was successful in 95 patients (96.9%). Immediate complete obliteration of the CCF was achieved in 93.9% of patients, with 98% undergoing embolization with liquid embolic agents (LEAs) and 95.6% undergoing coiling alone. Complete CCF obliteration was higher in the transvenous than in the transarterial approach (94.3% vs 75%, p = 0.010). At ≥ 6 months follow-up, complete CCF obliteration was achieved in all patients (100%). The rate of procedure-related complications was higher following LEAs than with coiling alone (32.0% vs 15.6%). New cranial nerve (CN) palsy was diagnosed in 26.0% and 2.2% after embolization with LEAs and coiling alone, respectively (p = 0.001), with complete CN palsy recovery in 78.6%. Procedure-related intracranial hemorrhage occurred in 3 patients (3.1%). Two patients experienced an ischemic stroke following Onyx migration into the internal carotid artery. Ocular symptoms improved in 93% (83/89) of the patients who were followed. CONCLUSIONS: In this study, complete obliteration of an indirect CCF was achieved in more than 90% of patients. Despite the occurrence of some new postprocedural ocular CN palsy, ocular symptoms improved in most patients in long-term follow-up. The transvenous approach was the most effective method for treating the indirect CCF. Coiling was safer than LEAs for the embolization of the indirect CCF.

Treated unruptured cerebral aneurysm in elderly patients: a single center study.

INTRODUCTION: The increase in life expectancy raises the question of the treatment of unruptured intracranial aneurysms in extremely old patients (>80 years). We present results in terms of occlusion and complications in both symptomatic and asymptomatic aneurysm. METHODS: All patients aged >80 years admitted to the Foundation Adolphe de Rothschild between January 1, 2005 and March, 2023 were included. Aneurysms were grouped as compressive and non-compressive. Procedural complications were grouped as symptomatic (i.e., leading to any temporary or permanent neurological deficit) and severe (defined by modified Rankin Scale (mRS) ≥3 at follow-up). RESULTS: Forty-two aneurysms were treated in the study period. Coiling (with or without remodeling) was the treatment of choice in 30 patients. Eighteen patients had compressive aneurysm. Six complications occurred (14.2%), all ischemic. The majority of complications occurred in symptomatic aneurysms, in 4 patients (66.6%). One of the patients treated by flow-diverter had severe complications (mRs ≥3) with hemiplegia. CONCLUSION: In extremely specific cases, treatment of unruptured aneurysm in people older than 80 years may be considered. Compressive aneurysm is associated with a high risk of complications. Treatments can be endovascular. Further prospective studies are required to confirm this hypothesis.

Mutation of key signaling regulators of cerebrovascular development in vein of Galen malformations.

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and most severe of congenital brain arteriovenous malformations, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP (RASA1) harbored a genome-wide significant burden of loss-of-function de novo variants (2042.5-fold, p = 4.79 x 10-7). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 (EPHB4) (17.5-fold, p = 1.22 x 10-5), which cooperates with p120 RasGAP to regulate vascular development. Additional probands had damaging variants in ACVRL1, NOTCH1, ITGB1, and PTPN11. ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomic analysis defined developing endothelial cells as a likely spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant (Phe867Leu) exhibited disrupted developmental angiogenesis and impaired hierarchical development of arterial-capillary-venous networks, but only in the presence of a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have implications for patients and their families.

Genetic dysregulation of an endothelial Ras signaling network in vein of Galen malformations.

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and severe congenital brain arteriovenous malformation, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP ( RASA1 ) harbored a genome-wide significant burden of loss-of-function de novo variants (p=4.79×10 -7 ). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 ( EPHB4 ) (p=1.22×10 -5 ), which cooperates with p120 RasGAP to limit Ras activation. Other probands had pathogenic variants in ACVRL1 , NOTCH1 , ITGB1 , and PTPN11 . ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomics defined developing endothelial cells as a key spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant exhibited constitutive endothelial Ras/ERK/MAPK activation and impaired hierarchical development of angiogenesis-regulated arterial-capillary-venous networks, but only when carrying a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have clinical implications.

Proposed new classification for internal carotid artery segmental agenesis based on embryologic and angiographic correlation.

BACKGROUND AND PURPOSE: Internal carotid artery (ICA) agenesis is a rare anatomical variant that can involve different segments of the ICA. Although many authors proposed their own classifications of this variant basing on different criteria, none of these allows to include all the cases described in the literature. The aim of the authors is to propose a new classification that allows to include all cases of ICA agenesis described until now. MATERIALS AND METHODS: The study is based on the review of all the cases of ICA agenesis described in the literature and of the classifications already proposed. After the analysis of these cases, we looked for the limits of each classification to elaborate a new more complete one. RESULTS: We found 228 cases of ICA agenesis. Among them 40 were not includible in the existing classifications. For this reason, we proposed a new classification based on the type of flow compensation and on the embryological events that determine the different variants. The flow is compensated in Type I by the Circle of Willis; in Type II by the non-regression of an embryonic artery; in Type III by the presence of an arterio-arterial anastomosis and in Type IV by external-internal carotid arteries anastomoses. CONCLUSION: After the literature review, we proposed a new comprehensive classification based on the detailed analysis of arterial embryology. Even if all the embryological details that determine this complex variant are not completely understood yet, this classification allows to include all the cases described in literature.

High thrombus platelet content is associated with a lower rate of first pass effect in stroke treated by endovascular therapy.

Background and purpose: First pass effect (FPE), the occurrence of complete reperfusion after one pass with no rescue attempt during endovascular therapy (EVT), is associated with the best clinical outcome after an acute ischemic stroke (AIS). Previous studies evaluating FPE occurrence according to EVT technical strategies, occlusion locations, or thrombus composition have provided controversial results. Here, we performed a correlation analysis between FPE occurrence and AIS thrombus cellular composition, as assessed using quantitative biochemical assays. Patients and methods: Homogenates of AIS thrombi from 250 patients were prepared by mechanical grinding. Platelet, red blood cell (RBC), and leukocyte contents of AIS thrombi were respectively estimated by quantification of GP (glycoprotein) VI, heme, and DNA in thrombus homogenates. FPE was defined as a modified Thrombolysis in Cerebral Infraction (mTICI) score of 2C or 3 after a single EVT device pass. Results: AIS thrombi successfully removed after a single pass were poorer in GPVI (0.098 ± 0.023 vs 0.111 ± 0.024 ng/mg, p < 0.001) compared to those whose removal had required several passes. GPVI content was also significantly associated with a higher number of device passes and a longer procedure time. No such significant correlation was found with DNA and heme content. Discussion and conclusion: Thrombus platelet content may hamper thrombus removal by EVT. This result suggests that adjunctive therapies or functionalization of retrieval devices targeting platelets may improve EVT efficacy.

Arteriovenous Cerebral High Flow Shunts in Children: From Genotype to Phenotype.

Objective: To study the genotypes and phenotypes of cerebral arteriovenous fistulas that drain or do not drain through the vein of Galen, and true vein of Galen aneurysmal malformations, in order to determine whether genotyping could help improve classification of these malformations and their management. Methods: We carried out a retrospective review of genetic and phenotypic data in databases of four centers. All children with cerebral arteriovenous fistula or vein of Galen aneurysmal malformations aged below 18 years at onset were included. We recorded the nature of the genetic variant or absence of variant, age at onset, type of malformation, symptoms at onset (hemorrhage, neurological deficit, hydrocephalus, incidental, and heart failure), type of venous drainage and the long-term outcome. Results: One hundred and fifteen children were included. Autosomal dominant variants were identified in 39% of patients. The most frequent variant affected was the RASA1 gene (25%) followed by EPHB4 (8%) and the HHT-associated genes (5%). HHT gene variants were only observed in pial arteriovenous fistula not draining into the vein of Galen; on the contrary, EPHB4 variants were only seen in genuine vein of Galen aneurysmal malformation. RASA1 variants were identified in all types of shunts. Conclusions: EPHB4 variants seem specific to the vein of Galen aneurysmal malformation, RASA1 variants are associated with either pial arteriovenous fistulas or with genuine VGAM and HHT gene variants seem specific to pial arteriovenous fistulas. The genetic data helps to classify these malformations and to guide treatment toward lowest risk of post-operative cerebral ischemic-hemorrhagic complications.

Endovascular treatment of anterior cranial base dural arteriovenous fistulas as a first-line approach: a multicenter study.

OBJECTIVE: Anterior cranial fossa dural arteriovenous fistulas (DAVFs) have been almost exclusively considered as surgical lesions. However, new advances in endovascular technology have made the endovascular treatment (EVT) of ethmoidal DAVFs feasible. The aim of this study was to report the clinical and angiographic outcomes of patients harboring DAVFs of the anterior cranial fossa who had undergone EVT as a first-line approach. METHODS: This was a retrospective study of a consecutive series of patients harboring anterior cranial base DAVFs who had undergone EVT as a first-line approach at four institutions. Angiographic follow-up was performed at 6 months. Immediate and late serious clinical events were assessed during follow-up, including death and stroke. Special emphasis was given to visual status before and after the treatment. RESULTS: Between 2008 and 2020, 37 patients with ethmoidal DAVFs were admitted to the participating centers. In 2 patients, EVT was not attempted; therefore, 35 patients underwent EVT as a first-line procedure. An isolated transarterial approach was performed in 19 (54.3%) patients. The transvenous approach was performed exclusively in 12 (34.3%) patients, and combined access was used in 4 (11.4%) patients. The most frequently used arterial access route was the ophthalmic artery in 82.6% of the patients. Immediately, complete angiographic occlusion was achieved in 31 (91.2%) of 34 patients whose treatment was accomplished. Six-month control angiography revealed that 30 (88.2%) DAVFs were totally occluded. Complications occurred in 3 (8.8%) patients, including 1 (2.9%) patient who had central retinal artery occlusion. No significant difference in complications or occlusion rates was noted between the transarterial and transvenous approaches. CONCLUSIONS: Most anterior cranial base DAVFs can be successfully treated via an endovascular approach. Neurological and visual complications are rare, even if the ophthalmic artery is used as the primary access route. Efforts should be focused on prospectively comparing the results of EVT and surgical management.

Embryology of the anterior communicating artery complex: implications on possible adult variants.

The anterior cerebral artery (ACA) and the anterior communicating artery (AComA) are important arteries of the telencephalon and are prominent location for cerebral aneurysms. Their embryological development is closely linked, and explains the possible variants seen in adults. In this paper, we present details related to the development of these two arteries, focusing on some variants such as the infra-optic course of the ACA, the unpaired ACA, and the persistent primitive olfactory artery.

Paediatric intracranial dural arteriovenous shunts: types, clinical presentation and therapeutic management.

Paediatric intracranial dural arteriovenous shunts have clinical presentations and evolutions, with angiographic characteristics that differ from those described in adults. We report our experience concerning their therapeutic management, emphasizing the relevance of early diagnosis and appropriate treatment for satisfactory neurocognitive development. Using a prospective database, we reviewed the clinical and radiological data of all children with dural arteriovenous shunts managed between 2002 and 2020. Dural shunts were categorized into three types: dural sinus malformations with arteriovenous shunts; infantile dural arteriovenous shunts; and adult-type dural arteriovenous shunts. Therapeutic strategies and outcomes were analysed depending on lesional subtypes. Modified Rankin Scale for the paediatric population was assessed pre-treatment and at last follow-up. Twenty-eight patients [16 girls (57.1%); 12 boys (42.9%)] were included: 17 dural sinus malformation [10 boys (58.8%); seven girls (41.2%)], three infantile shunts [three girls (100%)], eight adult-type shunts [four girls (50%)]; four boys (50%)], with a mean age of 19.2 ± 36.6 months at presentation. Twelve (42.9%) had a modified Rankin Scale score of 0-2, four (14.3%) had a score of 3, three (10.7%) had a score of 4 and eight (28.6%) had a score of 5. Embolization was performed in 22 children [78.6%; 12 girls (54.5%); 10 boys (45.5%)]. Fifteen patients could be cured (68.2%): 11 dural sinus malformations (73.3%), four adult-type lesions (100%) but no infantile shunt. Mean post-treatment follow-up was 39.5 months (max. 139 months): 14 patients (63.6%) presented a modified Rankin Scale score of 0-2 and eight (36.4%) had a score ≥3. In the dural sinus malformation group, the modified Rankin Scale score was improved in 11 patients (73.3%) and unchanged in three (20%). Only one patient with infantile subtype (33.3%) improved clinically. In the adult-subtype group, all children (100%) improved. Of six untreated patients [four girls (66.7%); two boys (33.3%)], four with adult-subtype shunts showed uneventful evolutions, one with dural sinus malformation died, and therapeutic abortion was conducted in an antenatally diagnosed dural sinus malformation. Paediatric dural fistulas comprise different subtypes with variable clinical courses. Proper diagnosis is mandatory for optimal therapeutic strategies within appropriate therapeutic windows.

Non-ischemic cerebral enhancing lesions after thrombectomy: a multicentric retrospective French national registry.

To report the occurrence of non-ischemic cerebral enhancing (NICE) lesions following mechanical thrombectomy (MT) through the retrospective French nationwide registry of NICE lesions. All thrombectomy capable stroke centers (TSC) in France were invited to fill out a questionnaire disseminated through a trainee-led research network (JENI-RC: Jeunes en Neuroradiologie Interventionnelle-Research Collaborative). NICE lesions were defined according to previous literature as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema and vascular distribution in the territory of the MT with no other confounding disease. All 43 TSC French centers responded. Three patients were reported by 3 different centers over a total of 34,824 MT (2015-2020). Patient no. 1 developed symptomatic NICE lesions 8 weeks after MT with combination of aspiration and stentriever for a right middle cerebral artery occlusion. Patient no. 2 developed asymptomatic NICE lesions 5 weeks after MT with direct thromboaspiration for a right middle cerebral artery occlusion. Patient no. 3 developed symptomatic NICE lesions 6 weeks after MT with direct thromboaspiration, and combination of aspiration and stentriever for a basilar artery occlusion. This study provides evidence that NICE lesions following MT are a possible rare complication with a similar presentation as previously described following endovascular aneurysm treatment. Both radiologists and neurologists should be aware of this adverse event and make use of MRI contrast agents in case of unexplained symptoms/images during follow-up after MT.

Intravenous abciximab as a rescue therapy for immediate reocclusion after successful mechanical thrombectomy in acute ischemic stroke patients.

Immediate reocclusion after mechanical thrombectomy (MT) for acute ischemic stroke (AIS) is a rare but devastating condition associated with poor functional outcome. The aim of this study was to gain insights into the mechanisms underlying immediate reocclusion, and to evaluate the efficacy and safety of the glycoprotein IIb/IIIa antagonist abciximab, for its treatment. Clinical data were collected from April 2015 to April 2019 in a monocentric prospective registry of AIS patients treated by MT. All patients with immediate reocclusion were retrospectively selected and subdivided into 2 groups according to abciximab treatment status. In vitro, the separate and combined effects of abciximab and alteplase on clot formation in whole blood under flow conditions were further investigated in microfluidic chambers. From 929 MT-treated patients, 21 had post-MT immediate reocclusion. Abciximab treatment in reocclusion patients (n = 10) led to higher rate of final recanalization (p < .001) while it did not increase bleeding complications. Flow chamber experiments revealed that, in contrast to alteplase, abciximab efficiently limits thrombus accretion from flowing blood by blocking platelet aggregation. Our results underscore a key role for platelet aggregation and the potential of Glycoprotein IIb/IIIa antagonists as a rescue therapy in post-MT immediate reocclusion.

The ARTISSE intrasaccular device for intracranial aneurysm treatment: short-term, mid-term and long-term clinical and angiographic results.

BACKGROUND: The concept of intra-aneurysmal flow disruption has emerged as a new paradigm for the treatment of primarily bifurcation aneurysms. The purpose of this study was to determine the clinical and angiographic outcomes of patients treated with the new ARTISSE intrasaccular device (ISD). METHODS: Selected patients with bifurcation aneurysms that matched the indications of the ARTISSE ISD defined by the manufacturer were treated in a single center. Clinical and angiographic follow-up was conducted at 6 and 36 months. Aneurysm occlusion was assessed using the Raymond-Roy classification scale. RESULTS: Nine subjects with nine unruptured bifurcation aneurysms were enrolled. Mean aneurysm size was 7.2±1.2 mm (range 5.5-9.7 mm). An adequate aneurysm occlusion (defined as a complete occlusion or a neck remnant) was achieved in 6/9 patients (66.7%) at 6 months and 4/7 patients (57.1%) at 36 months follow-up. Two of the nine subjects experienced a major stroke (22.2%), including one on postoperative day 1 due to a procedure-related parent vessel occlusion and subsequent ischemic stroke. The other major stroke occurred within the 36-month follow-up period during treatment of a separate aneurysm with coils, leading to perforation with hemorrhagic stroke causing a permanent neurological deficit. CONCLUSION: The ARTISSE ISD was successfully deployed in all nine cases. There were, however, several procedure-related complications and results in terms of angiographic aneurysm occlusion were modest.

Association of Hypotension During Thrombectomy and Outcomes Differs With the Posterior Communicating Artery Patency.

BACKGROUND AND PURPOSE: Hypotension during endovascular therapy for acute ischemic stroke is associated with worse functional outcomes (FO). Given its important role in intracranial hemodynamics, we investigated whether hypotension during endovascular therapy had the same effect on FO according to the posterior communicating artery (PComA) patency. METHODS: We performed a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). Patients were included if they had middle cerebral artery occlusions. Primary outcome was favorable FO, defined by a modified Rankin Scale scores between 0 and 2 at 3 months. RESULTS: One hundred forty-eight patients with middle cerebral artery occlusion were included. In patients with no PComA, an increase in minimum mean arterial pressure was positively associated with favorable FO (odds ratio per 10 mm Hg increase, 1.59 [95%CI, 1.11-2.25]; P=0.010), whereas no association was found in patients with a PComA (odds ratio, 0.77 [95% CI, 0.54-1.08]; P=0.12). Patients with no PComA and longer cumulative time with mean arterial pressure <90 mm Hg or systolic blood pressure <140 mm Hg had significantly lower rates of favorable FO, with an odds ratio per 10-minute increase of 0.75 (95% CI, 0.59-0.94; P=0.010) and 0.74 (95% CI, 0.60-0.91; P=0.003), but not in patients with a PComA. CONCLUSIONS: Hypotension during endovascular therapy for middle cerebral artery occlusion is consistently associated with worse FO in patients with no PComA but not in those with a PComA. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02523261.

Timing and Spectrum of Neurological Complications After Flow Diverter Implantation for Intracranial Aneurysms.

Background and Purpose: The aim of this study was to characterize neurological complications after flow diverter (FD) treatment on a long follow-up cohort and identify predictive factors associated with these complications. Methods: This study was conducted on a monocentric cohort of patients treated for intracranial aneurysms by FD. Results: Between September 2008 and July 2018, 413 patients were treated for 514 aneurysms: 18% of the patients presented with at least one neurological complication during a median follow-up of 446 days (IQR 186-1,210). Sixty-one patients presented with ischemic complications, 13 with hemorrhagic ones and 10 with compressive processes. Among 89 neurological complications 64.5% were peri-operative (occurring within the 30 days following the procedure) and 35.5% were delayed after 1 month. Conclusions: Overall, neurological complications after FD implantation were overrepresented by cerebrovascular ischemic events occurring during the peri-operative period, but also in a delayed manner after 1 year. Long-term follow-up is relevant after aneurysm intervention using FD.

Safety and efficacy of intensive blood pressure lowering after successful endovascular therapy in acute ischaemic stroke (BP-TARGET): a multicentre, open-label, randomised controlled trial.

BACKGROUND: High systolic blood pressure after successful endovascular therapy for acute ischaemic stroke is associated with increased risk of intraparenchymal haemorrhage. However, no randomised controlled trials are available to guide optimal management. We therefore aimed to assess whether an intensive systolic blood pressure target resulted in reduced rates of intraparenchymal haemorrhage compared with a standard systolic blood pressure target. METHODS: We did a multicentre, open-label, randomised controlled trial at four academic hospital centres in France. Eligible individuals were adults (aged ≥18 years) with an acute ischaemic stroke due to a large-vessel occlusion that was successfully treated with endovascular therapy. Patients were randomly assigned (1:1) to either an intensive systolic blood pressure target group (100-129 mm Hg) or a standard care systolic blood pressure target group (130-185 mm Hg), by means of a central web-based procedure, stratified by centre and intravenous thrombolysis use before endovascular therapy. In both groups, the target systolic blood pressure had to be achieved within 1 h after randomisation and maintained for 24 h with intravenous blood pressure lowering treatments. The primary outcome was the rate of radiographic intraparenchymal haemorrhage at 24-36 h and the primary safety outcome was the occurrence of hypotension. Analyses were done on an intention-to-treat basis. BP-TARGET is registered with ClinicalTrials.gov, number NCT03160677, and the trial is closed at all participating sites. FINDINGS: Between June 21, 2017, and Sept 27, 2019, 324 patients were enrolled in the four participating stroke centres: 162 patients were randomly assigned to the intensive target group and 162 to the standard target group. Four (2%) of 162 patients were excluded from the intensive target group and two (1%) of 162 from the standard target group for withdrawal of consent or legal reasons. The mean systolic blood pressure during the first 24 h after reperfusion was 128 mm Hg (SD 11) in the intensive target group and 138 mm Hg (17) in the standard target group. The primary outcome was observed in 65 (42%) of 154 patients in the intensive target group and 68 (43%) of 157 in the standard target group on brain CT within 24-36 h after reperfusion] (adjusted odds ratio 0·96, 95% CI 0·60-1·51; p=0·84). Hypotensive events were not significantly different between both groups and occurred in 12 (8%) of 158 patients in the intensive target and five (3%) of 160 in the standard target group. Mortality within the first week after randomisation occurred in 11 (7%) of 158 patients in the intensive target group and in seven (4%) of 160 in the standard target group. INTERPRETATION: An intensive systolic blood pressure target of 100-129 mm Hg after successful endovascular therapy did not reduce radiographic intraparenchymal haemorrhage rates at 24-36 h as compared with a standard care systolic blood pressure target of 130-185 mm Hg. Notably, these results are applicable to patients with successful reperfusion and systolic blood pressures of more than 130 mm Hg at the end of procedure. Further studies are needed to understand the association between blood pressure and outcomes after reperfusion. FUNDING: French Health Ministry.

Modeling Large Vessel Occlusion Stroke for the Evaluation of Endovascular Therapy According to Thrombus Composition.

More than 40% of endovascular therapy (EVT) fail to achieve complete reperfusion of the territory of the occluded artery in patients with acute ischemic stroke (AIS). Understanding factors influencing EVT could help overcome its limitations. Our objective was to study the impact of thrombus cell composition on EVT procedures, using a simulation system for modeling thrombus-induced large vessel occlusion (LVO) in flow conditions. In an open comparative trial, we analyzed the behavior of size-standardized platelet-rich and red blood cells (RBC)-rich thrombi during simulated stent retriever-mediated EVT procedures. Sixteen simulated EVT procedures were performed (8 RBC- vs. 8 platelet-rich thrombi). Platelet-rich thrombi were associated with a higher number of stent retriever passes (p = 0.03) and a longer procedure duration (p = 0.02) compared to RBC-rich thrombi. Conversely, RBC-rich thrombi released more embolic fragments than platelet-rich thrombi (p = 0.004). Both RBC-rich and platelet-rich thrombi underwent drastic compaction after being injected into the in vitro circulation model, and histologic analyses showed that these EVT-retrieved thrombi displayed features comparable to those previously observed in thrombi from patients with AIS patients having LVO, including a marked structural dichotomy between RBC- and platelet-rich areas. Our results show that the injection of in vitro-produced thrombi in artificial cerebrovascular arterial networks is suitable for testing recanalization efficacy and the risk of embolization of EVT devices and strategies in association with thrombus cell composition.

Rescue carotid puncture for ischemic stroke treated by endovascular therapy: a multicentric analysis and systematic review.

BACKGROUND: Endovascular therapy (EVT) for acute ischemic stroke (AIS) can be challenging in older patients with supra-aortic tortuosity. Rescue carotid puncture (RCP) can be an alternative in case of supra-aortic catheterization failure by femoral access, but data regarding RCP are scarce. We sought to investigate the feasibility, effectiveness and safety of RCP for AIS treated by EVT. METHODS: Patients treated by EVT with RCP were included from January 2012 to December 2019 in the Endovascular Treatment in Ischemic Stroke (ETIS) multicentric registry. Main outcomes included reperfusion rates ( ≥ TICI2B), 3 month functional outcome (modified Rankin Scale) and 3 month mortality. We also performed an additional systematic review of the literature according to the PRISMA checklist to summarize previous studies on RCP. RESULTS: 25 patients treated by EVT with RCP were included from the ETIS registry. RCP mainly concerned elderly patients (median age 85 years, range 73-92) with supra-aortic tortuosity (n=16 (64%)). Intravenous thrombolysis (IVT) was used for nine patients (36%). Successful reperfusion was achieved in 64%, 87.5% of patients were dependent at 3 months, and 3 month mortality was 45.8%. The systematic review yielded comparable results. In pooled individual data, there was a shift toward better functional outcome in patients with successful reperfusion (median (IQR) 4 (2-6) vs 6 (4-6), p=0.011). CONCLUSION: RCP mainly concerned elderly patients admitted for AIS with anterior LVO with supra-aortic tortuosity. The procedure seemed feasible, notably for patients treated with IVT, and led to significant reperfusion rates at the end of procedure, but with pronounced unfavorable outcomes at 3 months. RCP should be performed under general anesthesia to avoid life-threatening complications and ensure airways safety. Finally, RCP led to low rates of closure complications, emphasizing that this concern should not withhold RCP, if indicated.

Endovascular treatment as the main approach for Spetzler-Martin grade III brain arteriovenous malformations.

BACKGROUND: Because Spetzler-Martin (SM) grade III brain arteriovenous malformations (bAVMs) constitute a heterogeneous group of lesions with various combination of sizes, eloquence, and venous drainage patterns, their management is usually challenging. The aim of this study is to evaluate the clinical/imaging outcomes and the procedural safety of endovascular approach as the main treatment for the cure of SM grade III bAVMs. METHODS: In this retrospective study, prospectively collected data of SM grade III bAVMs treated by endovascular techniques between 2010 and 2018 at our hospital were reviewed. Patients older than 16 years with angiographic follow-up of at least 6 months after endovascular treatment were entered in the study. The patients had a mean follow-up of 12 months. The data were assessed for clinical outcome (modified Rankin Scale), permanent neurological deficit, post-operative complications, and optimal imaging outcome, defined by complete exclusion of AVM. The independent predictive variables of poor outcome or hemorrhagic complication were assessed using binary logistic regression. RESULTS: Sixty-five patients with 65 AVMs were included in the study. Mean age of the patients was 40.0±14.4. Most common presentation was hemorrhage (61.5%). The patients underwent one to eight endovascular procedures (median=2). Mean nidus diameter was 30.2±13.0. A complete obliteration of AVM was achieved in 57 patients (87.7%). Post-procedure significant hemorrhagic and ischemic complications were seen in 13 (20%) and five (7.7%) patients respectively, leading to five (7.7%) transient and four (6.2%) permanent neurological deficits. Eight patients (12.3%) experienced worsening of mRS after embolization. Ten patients (15.4%) had poor outcome (mRS 3-5) at follow-up and two (3%) died. CONCLUSIONS: Endovascular treatment can achieve a high rate of complete exclusion of grade III AVM but may be associated (as in other treatment modalities) with significant important complications. CLINICAL TRIAL REGISTRATION NUMBER: NCT02879071.