Catheter navigation support for mechanical thrombectomy guidance: 3D/2D multimodal catheter-based registration with no contrast dye fluoroscopy.

PURPOSE: The fusion of pre-operative imaging and intra-operative fluoroscopy may support physicians during mechanical thrombectomy for catheter navigation from the aortic arch to carotids. Nevertheless, the aortic arch volume is too important for intra-operative contrast dye injection leading to a lack of common anatomical structure of interest that results in a challenging 3D/2D registration. The objective of this work is to propose a registration method between pre-operative 3D image and no contrast dye intra-operative fluoroscopy. METHODS: The registration method exploits successive 2D fluoroscopic images of the catheter navigating in the aortic arch. The similarity measure is defined as the normalized cross-correlation between a binary combination of catheter images and a pseudo-DRR resulting from the 2D binary projection of the pre-operative 3D image (MRA or CTA). The 3D/2D transformation is decomposed in out-plane and in-plane transformations to reduce computational complexity. The 3D/2D transformation is then obtained by maximizing the similarity measure through multiresolution exhaustive search. RESULTS: We evaluated the registration performance through dice score and mean landmark error. We evaluated the influence of parameters setting, aortic arch type and 2D navigation sequence duration. Results on a physical phantom and data from a patient who underwent a mechanical thrombectomy showed good registration accuracy with a dice score higher than 92% and a mean landmark error lower than the quarter of a carotid diameter (8-10 mm). CONCLUSION: A new registration method compatible with no contrast dye fluoroscopy has been proposed to guide the crossing from aortic arch to a carotid in mechanical thrombectomy. First evaluation showed the feasibility and accuracy of the method as well as its compatibility with clinical routine practice.

Longitudinal radiological follow-up of individual level non-ischemic cerebral enhancing lesions following endovascular aneurysm treatment.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions following aneurysm endovascular therapy are exceptionally rare, with unknown longitudinal evolution. OBJECTIVE: To evaluate the radiological behavior of individual NICE lesions over time. METHODS: Patients included in a retrospective national multicentric inception cohort were analyzed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm treatment, with no other confounding disease. Lesion burden and the longitudinal behavior of individual lesions were assessed. RESULTS: Twenty-two patients were included, with a median initial lesion burden of 36 (IQR 17-54) on the first MRI scan. Of the 22 patients with at least one follow-up MRI scan, 16 (73%) had new lesions occurring mainly within the first 200 weeks after the date of the procedure. The median number of new lesions per MRI was 6 (IQR 2-16). Among the same 22 patients, 7 (32%) had recurrent lesions. The median persistent enhancement of a NICE lesion was 13 weeks (IQR 6-30). No factor was predictive of early regression of enhancement activity with lesion regression kinetics mainly being patient-dependent. CONCLUSIONS: The behavior of individual NICE lesions was found to be highly variable with an overall patient-dependent regression velocity.

Rehearsals using patient-specific 3D-printed aneurysm models for simulation of endovascular embolization of complex intracranial aneurysms: 3D SIM study.

BACKGROUND: In neurovascular treatment planning, endovascular devices to manage complex intracranial aneurysms requiring intervention are often selected based on conventional measurements and interventional neuroradiologist experience. A recently developed technology allows a patient-specific 3D-printed model to mimic the navigation experience. The goal of this study was to assess the effect of pre-procedure 3D simulation on procedural and clinical outcomes for wide-neck aneurysm embolization. MATERIALS & METHODS: In this unblinded, non-randomized, prospective, multicenter study conducted from November 18 through December 20, patients with complex intracranial aneurysms (neck > 4 mm or ratio < 21) were treated by WEB or flow diverter stents (FDS). The primary endpoint was concordance between simulation and procedure, 3D-printed model accuracy as well as embolization outcomes including complications, procedure times, and radiation dose were also assessed. Secondary endpoint was to compare versus a retrospective WEB cohort. RESULTS: Twenty-one patients were treated, 76% of cases by WEB and 24% by FDS. Concordance between post-simulation and real procedure efficiency was 0.85 [0.69 - 1.00] for size device selection and 0.93 [0.79 - 1.00] for wall-apposition/aneurysm neck closure. Geometrical accuracy of the 3D-printed model showed a mean absolute shift of 0.11 mm. Two complications without major clinical impact were reported with a post-operative mRS similar to pre-procedure mRS for all patients. CONCLUSIONS: Rehearsal using accurate 3D-printed patient-specific aneurysm models enabled optimization of embolization strategy, resulting in reduced procedure duration and cumulative fluoroscopy time which translated to reduced radiation exposure compared to procedures performed without simulation.

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey.

BACKGROUND: Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France. METHODS: In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC). RESULTS: All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications. CONCLUSION: This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field.

Effect of intravenous thrombolysis before endovascular therapy on outcome according to collateral status: insight from the ETIS Registry.

BACKGROUND: It is unknown whether collateral status modifies the effect of pretreatment intravenous thrombolysis (IVT) on the outcomes of patients with large vessel occlusions treated with endovascular therapy (EVT). We aimed to assess whether collateral status modifies the effect of IVT on the outcomes of EVT in clinical practice. METHODS: We used data from the ongoing prospective multicentric Endovascular Treatment in Ischemic Stroke (ETIS) Registry in France. Patients with anterior circulation proximal large vessel occlusions treated with EVT within 6 hours of symptom onset were enrolled. Patients were divided into two groups based on pretreatment with IVT. The two groups were matched based on baseline characteristics. We tested the interaction between collateral status and IVT in unadjusted and adjusted models. RESULTS: A total of 1589 patients were enrolled in the study, of whom 55% received IVT. Using a propensity score matching method, 724 no IVT patients were matched to 549 IVT patients. In propensity score weighted analysis, IVT was associated with higher odds of early neurological improvement (OR 1.74; 95% CI 1.33 to 2.26), favorable functional outcome (OR 1.66; 95% CI 1.23 to 2.24), excellent functional outcome (OR 2.04; 95% CI 1.47 to 2.83), and successful reperfusion (OR 2.18; 95% CI 1.51 to 3.16). IVT was not associated with mortality or hemorrhagic complications. There was no interaction between collateral status and IVT association with any of the outcomes. CONCLUSIONS: Collateral status does not modify the effect of pretreatment IVT on the efficacy and safety outcomes of EVT.

Thrombectomy in basilar artery occlusions: impact of number of passes and futile reperfusion.

BACKGROUND: The number of mechanical thrombectomy (MT) passes is strongly associated with angiographic reperfusion as well as clinical outcomes in patients with anterior circulation ischemic stroke. However, these associations have not been analyzed in patients with basilar artery occlusion (BAO). We investigated the influence of the number of MT passes on the degree of reperfusion and clinical outcomes, and compared outcome after ≤3 passes versus >3 passes. METHODS: We used data from the prospective multicentric Endovascular Treatment in Ischemic Stroke (ETIS) Registry at 18 sites in France. Patients with BAO treated with MT were included. The primary outcome was a favorable outcome, defined as a modified Rankin Scale score of 0-3 at 90 days. We fit mixed multiple regression models, with center as a random effect. RESULTS: We included 275 patients. Successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) 2b-3) was achieved in 88.4%, and 41.8% had a favorable outcome. The odds ratio for favorable outcome with each pass above 1 was 0.41 (95% CI 0.23 to 0.73) and for recanalization (mTICI 2b-3) it was 0.70 (95% CI 0.57 to 0.87). In patients with ≤3 passes, the rate of favorable outcome in recanalized versus non-recanalized patients was 50.5% versus 10.0% (p=0.001), while in those with >3 passes it was 16.7% versus 15.2% (p=0.901). CONCLUSIONS: We found that BAO patients had a significant relationship between the number of MT passes and both recanalization and favorable functional outcome. We further found that the benefit of recanalization in BAO patients was significant only when recanalization was achieved within three passes, encouraging at least three passes before stopping the procedure.

Poor clinical outcome despite successful basilar occlusion recanalization in the early time window: incidence and predictors.

BACKGROUND: Endovascular treatment (EVT) for basilar artery occlusions (BAO) is associated with a higher rate of futile recanalization compared with anterior circulation procedures. We aimed to identify the incidence and predictors of poor clinical outcome despite successful reperfusion in current clinical practice. METHODS: We used data from the ETIS (Endovascular Treatment in Ischemic Stroke) registry, a prospective multicenter observational registry of stroke treated with EVT in France. Patients undergoing EVT for acute BAO from January 2014 to May 2019 successfully treated within 8 hours from onset were included. Predictors of 90-day poor outcome (modified Rankin Scale (mRS) 4-6) were researched within patients with successful (modified Thrombolysis In Cerebral Infarction (mTICI 2b-3)) and excellent (mTICI 2c-3) reperfusion. RESULTS: Among 242 patients treated within 8 hours, successful reperfusion was achieved in 195 (80.5%) and excellent reperfusion in 120 (49.5%). Poor outcome was observed in 107 (54.8%) and 60 (50%) patients, respectively. In patients with successful early reperfusion, age, higher initial National Institutes of Health Stroke Scale (NIHSS) score, lower posterior circulation Alberta Stroke Programme Early CT Score (pc-ASPECTS), and absence of prior intravenous thrombolysis were independent predictors of poor outcome. The only treatment factor with an independent predictive value was first-pass mTICI 2b-3 reperfusion (adjusted OR 0.13, 95% CI 0.05 to 0.37, p<0.001). In patients with excellent early reperfusion, independent predictors were age, initial NIHSS score, first-pass mTICI 2c-3 reperfusion, and hemorrhagic transformation on post-interventional imaging. CONCLUSIONS: Early successful reperfusion with EVT occurred in 80.5% of patients, and the only treatment-related factor predictive of clinical outcome was first pass mTICI 2b-3 reperfusion. Further research is warranted to identify the optimal techniques and devices associated with first pass reperfusion in the posterior circulation.

Influence of prior intravenous thrombolysis in patients treated with mechanical thrombectomy for M2 occlusions: insight from the Endovascular Treatment in Ischemic Stroke (ETIS) registry.

BACKGROUND: Intravenous thrombolysis (IVT) for patients treated with mechanical thrombectomy (MT) for proximal occlusions has recently been questioned through randomized trials. However, few patients with M2 occlusions were included. We investigated the influence of prior IVT for patients presenting M2 occlusions treated with MT in comparison with MT alone. METHODS: We conducted a retrospective analysis of the Endovascular Treatment in Ischemic Stroke (ETIS) registry, a multicenter observational study. Data from consecutive patients treated with MT for M2 occlusions between January 2015 and January 2022 at 26 comprehensive stroke centers were analyzed. The primary endpoint was 90-day modified Rankin Scale score of 0-2. Outcomes were compared using propensity score approaches. We also performed sensitivity analysis in relevant subgroups of patients. RESULTS: Among 1132 patients with M2 occlusions treated with MT, 570 received prior IVT. The two groups were comparable after propensity analysis. The rate of favorable functional outcome was significantly higher in the IVT+MT group compared with the MT alone group (59.8% vs 44.7%; adjusted OR 1.38, 95% CI 1.10 to 1.75, P=0.008). Hemorrhagic and procedural complications were similar in both groups. In sensitivity analysis excluding patients with anticoagulation treatment, favorable recanalization was more frequent in the IVT+MT group (OR 1.37, 95% CI 1.11 to 1.70, P=0.004). CONCLUSIONS: In cases of M2 occlusions, prior IVT combined with MT resulted in better functional outcome than MT alone, without increasing the rate of hemorrhagic or procedural complications. These results suggest the benefit of IVT in patients undergoing MT for M2 occlusions.

First-line thrombectomy strategy for anterior large vessel occlusions: results of the prospective ETIS egistry.

BACKGROUND: The best recanalization strategy for mechanical thrombectomy (MT) remains unknown as no randomized controlled trial has simultaneously evaluated first-line stent retriever (SR) versus contact aspiration (CA) versus the combined approach (SR+CA). OBJECTIVE: To compare the efficacy and safety profiles of SR, CA, and SR+CA in patients with acute ischemic stroke (AIS) treated by MT. METHODS: We analyzed data of the Endovascular Treatment in Ischemic Stroke (ETIS) Registry, a prospective, multicenter, observational study of patients with AIS treated by MT. Patients with M1 and intracranial internal carotid artery (ICA) occlusions between January 2015 and March 2020 in 15 comprehensive stroke centers were included. We assessed the association of first-line strategy with favorable outcomes at 3 months (modified Rankin Scale score 0-2), successful recanalization rates (modified Thrombolysis In Cerebral Infarction (mTICI) 2b/3), and safety outcomes. RESULTS: We included 2643 patients, 406 treated with SR, 1126 with CA, and 1111 with SR+CA. CA or SR+CA achieved more successful recanalization than SR for M1 occlusions (aOR=2.09, (95% CI 1.39 to 3.13) and aOR=1.69 (95% CI 1.12 to 2.53), respectively). For intracranial ICA, SR+CA achieved more recanalization than SR (aOR=2.52 (95% CI 1.32 to 4.81)), no differences were observed between CA and SR+CA. SR+CA was associated with lower odds of favorable outcomes compared with SR (aOR=0.63 (95% CI 0.44 to 0.90)) and CA (aOR=0.71 (95% CI 0.55 to 0.92)), higher odds of mortality at 3 months (aOR=1.56 (95% CI 1.22 to 2.0)) compared with CA, and higher odds of symptomatic intracranial hemorrhage (aOR=1.59 (95% CI 1.1 to 2.3)) compared with CA. CONCLUSIONS: Despite high recanalization rates, our results question the safety of the combined approach, which was associated with disability and mortality. Randomized controlled trials are needed to evaluate the efficacy and safety of these techniques.

Influence of prior intravenous thrombolysis on outcome after failed mechanical thrombectomy: ETIS registry analysis.

BACKGROUND: Despite constant improvements in recent years, sufficient reperfusion after mechanical thrombectomy (MT) is not reached in up to 15% of patients with large vessel occlusion stroke (LVOS). The outcome of patients with unsuccessful reperfusion after MT especially after intravenous thrombolysis (IVT) use is not known. We investigated the influence of initial IVT in this particular group of patients with failed intracranial recanalization. METHODS: We conducted a retrospective analysis of the Endovascular Treatment in Ischemic Stroke (ETIS) registry from January 2015 to December 2019. Patients presenting with LVOS of the anterior circulation and final modified Thrombolysis in Cerebral Infarction score (mTICI) of 0, 1 or 2a were included. Posterior circulation, isolated cervical carotid occlusions and successful reperfusions (mTICI 2b, 2c or 3) were excluded. The primary endpoint was favorable outcome (modified Rankin Scale score of 0-2) after 3 months. Secondary endpoints were safety outcomes including mortality, any intracranial hemorrhage (ICH), parenchymal hematoma (PH) and symptomatic intracranial hemorrhage (sICH) rates. RESULTS: Among 5076 patients with LVOS treated with MT, 524 patients with insufficient recanalization met inclusion criteria, of which 242 received IVT and 282 did not. Functional outcome was improved in the MT+IVT group compared with the MT alone group, although the difference did not reach statistical significance (23.0% vs 12.9%; adjusted OR=1.82; 95% CI 0.98 to 3.38; p=0.058). However, 3 month mRS shift analysis showed a significant benefit of IVT (adjusted OR=1.68; 95% CI 1.56 to 6.54). ICH and sICH rates were similar in both groups, although PH rate was higher in the MT+IVT group (adjusted OR=3.20; 95% CI 1.56 to 6.54). CONCLUSIONS: Among patients with LVOS in the anterior circulation and unsuccessful MT, IVT was associated with improved functional outcome even after unsuccessful MT. Despite recent trials questioning the place of IVT in the LVOS reperfusion strategy, these findings emphasize a subgroup of patients still benefiting from IVT.

Non-ischemic cerebral enhancing lesions after intracranial aneurysm endovascular repair: a retrospective French national registry.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions are exceptionally rare following aneurysm endovascular therapy (EVT). OBJECTIVE: To investigate the presenting features and longitudinal follow-up of patients with NICE lesions following aneurysm EVT. METHODS: Patients included in a retrospective national multicentre inception cohort were analysed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm EVT, with no other confounding disease. RESULTS: From a pool of 58 815 aneurysm endovascular treatment procedures during the study sampling period (2006-2019), 21/37 centres identified 31 patients with 32 aneurysms of the anterior circulation who developed NICE lesions (mean age 45±10 years). Mean delay to diagnosis was 5±9 months, with onset occurring a month or less after the index EVT procedure in 10 out of 31 patients (32%). NICE lesions were symptomatic at time of onset in 23 of 31 patients (74%). After a mean follow-up of 25±26 months, 25 patients (81%) were asymptomatic or minimally symptomatic without disability (modified Rankin Scale (mRS) score 0-1) at last follow-up while 4 (13%) presented with mild disability (mRS score 2). Clinical follow-up data were unavailable for two patients. Follow-up MRI (available in 27 patients; mean time interval after onset of 22±22 months) demonstrated persistent enhancement in 71% of cases. CONCLUSIONS: The clinical spectrum of NICE lesions following aneurysm EVT therapy spans a wide range of neurological symptoms. Clinical course is most commonly benign, although persistent long-term enhancement is frequent.

Patient and aneurysm factors associated with aneurysm recanalization after coiling.

BACKGROUND: One limitation of the endovascular treatment of intracranial aneurysms is aneurysm recanalization. The Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) study is a prospective multicenter cohort study evaluating the factors associated with recanalization after endovascular treatment. METHODS: The current analysis is focused on patients treated by coiling or balloon-assisted coiling (BAC). Postoperative, mid-term vascular imaging, and evolution of aneurysm occlusion were independently evaluated by two neuroradiologists. A 3-grade scale was used for aneurysm occlusion (complete occlusion, neck remnant, and aneurysm remnant) and for occlusion evolution (improved, stable, and worsened). Recanalization was defined as any worsening of aneurysm occlusion. RESULTS: Between December 2013 and May 2015, 16 French neurointerventional departments enrolled 1289 patients. A total of 945 aneurysms in 908 patients were treated with coiling or BAC. The overall rate of aneurysm recanalization at mid-term follow-up was 29.5% (95% CI 26.6% to 32.4%): 28.9% and 30.3% in the coiling and BAC groups, respectively. In multivariate analyses factors independently associated with recanalization were current smoking (36.6% in current smokers vs 24.5% in current non-smokers (OR 1.8 (95% CI 1.3 to 2.4); p=0.0001), ruptured status (31.9% in ruptured aneurysms vs 25.1% in unruptured (OR 1.5 (95% CI 1.1 to 2.1); p=0.006), aneurysm size ≥10 mm (48.8% vs 26.5% in aneurysms <10 mm (OR 2.6 (95% CI 1.8 to 3.9); p<0.0001), wide neck (32.1% vs 25.8% in narrow neck (OR 1.5 (95% CI 1.1 to 2.1); p=0.02), and MCA location (34.3% vs 28.3% in other locations (OR 1.5 (95% CI 1.0 to 2.1); p=0.04). CONCLUSIONS: Several factors are identified by the ARETA study as playing a role in aneurysm recanalization after coiling: current smoking, aneurysm status (ruptured), aneurysm size (≥10 mm), neck size (wide neck), and aneurysm location (middle cerebral artery). This finding has important consequences in clinical practice. TRIAL REGISTRATION NUMBER: URL: http://www. CLINICALTRIALS: gov; Unique Identifier: NCT01942512.

Collateral status reperfusion and outcomes after endovascular therapy: insight from the Endovascular Treatment in Ischemic Stroke (ETIS) Registry.

BACKGROUND: Studies have suggested that collateral status modifies the effect of successful reperfusion on functional outcome after endovascular therapy (EVT). We aimed to assess the association between collateral status and EVT outcomes and to investigate whether collateral status modified the effect of successful reperfusion on EVT outcomes. METHODS: We used data from the ongoing, prospective, multicenter Endovascular Treatment in Ischemic Stroke (ETIS) Registry. Collaterals were graded according to the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) guidelines. Patients were divided into two groups based on angiographic collateral status: poor (grade 0-2) versus good (grade 3-4) collaterals. RESULTS: Among 2020 patients included in the study, 959 (47%) had good collaterals. Good collaterals were associated with favorable outcome (90-day modified Rankin Scale (mRS) 0-2) (OR 1.5, 95% CI 1.19 to 1.88). Probability of good outcome decreased with increased time from onset to reperfusion in both good and poor collateral groups. Successful reperfusion was associated with higher odds of favorable outcome in good collaterals (OR 6.01, 95% CI 3.27 to 11.04) and poor collaterals (OR 5.65, 95% CI 3.32 to 9.63) with no significant interaction. Similarly, successful reperfusion was associated with higher odds of excellent outcome (90-day mRS 0-1) and lower odds of mortality in both groups with no significant interaction. The benefit of successful reperfusion decreased with time from onset in both groups, but the curve was steeper in the poor collateral group. CONCLUSIONS: Collateral status predicted functional outcome after EVT. However, collateral status on the pretreatment angiogram did not decrease the clinical benefit of successful reperfusion.

Endovascular reperfusion of M2 occlusions in acute ischemic stroke reduced disability and mortality: ETIS Registry results.

BACKGROUND: The predictors of successful reperfusion and the effect of reperfusion after endovascular treatment (EVT) for M2 occlusions have not been well studied. We aimed to identify predictors of successful reperfusion and the effect of reperfusion on outcomes of EVT for M2 occlusions in current practice. METHODS: Patients with acute ischemic stroke due to isolated M2 occlusions who were enrolled in the prospective multicenter Endovascular Treatment in Ischemic Stroke (ETIS) Registry in France between January 2015 and March 2020 were included. The primary outcome was a favorable outcome, defined as modified Rankin Scale (mRS) score of 0-2 at 90 days. Successful reperfusion was defined as an improvement of ≥1 points in the modified Thrombolysis In Cerebral Infarction score between the first and the last intracranial angiogram. RESULTS: A total of 458 patients were included (median National Institutes of Health Stroke Scale (NIHSS) score 14; 61.4% received prior intravenous thrombolysis). Compared with the non-reperfused patients, reperfused patients had an increased rate of excellent outcome (OR 2.3, 95% CI 0.98 to 5.36; p=0.053), favorable outcome (OR 2.79, 95% CI 1.31 to 5.93; p=0.007), and reduced 90-day mortality (OR 0.39, 95% CI 0.19 to 0.79; p<0.01). Admission NIHSS score was the only predictor of successful reperfusion. First-line strategy was not a predictor of successful reperfusion or favorable outcome, but the use of a stent retriever, alone or with an aspiration catheter, was associated with higher rates of procedural complications and 90-day mortality. CONCLUSIONS: Successful reperfusion of M2 occlusions reduced disability and mortality. However, safety is a concern, especially if the procedure failed.

Carotid artery direct access for mechanical thrombectomy: the Carotid Artery Puncture Evaluation (CARE) study.

BACKGROUND: In acute ischemic stroke due to anterior large vessel occlusion (AIS-LVO), accessing the target occluded vessel for mechanical thrombectomy (MT) is sometimes impossible through the femoral approach. We aimed to evaluate the safety and efficacy of direct carotid artery puncture (DCP) for MT in patients with failed alternative vascular access. METHODS: We retrospectively analyzed data from 45 stroke centers in France, Switzerland and Germany through two research networks from January 2015 to July 2019. We collected physician-centered data on DCP practices and baseline characteristics, procedural variables and clinical outcome after DCP. Uni- and multivariable models were conducted to assess risk factors for complications. RESULTS: From January 2015 to July 2019, 28 149 MT were performed, of which 108 (0.39%) resulted in DCP due to unsuccessful vascular access. After DCP, 77 patients (71.3%) had successful reperfusion (modified Thrombolysis In Cerebral Infarction (mTICI) score ≥2b) and 28 (25.9%) were independent (modified Rankin Scale (mRS) score 0-2) at 3 months. 20 complications (18.5%) attributed to DCP occurred, all of them during or within 1 hour of the procedure. Complications led to extension of the intubation time in the intensive care unit in 7 patients (6.4%) and resulted in death in 3 (2.8%). The absence of use of a hemostatic closure device was associated with a higher complication risk (OR 3.04, 95% CI 1.03 to 8.97; p=0043). CONCLUSION: In this large multicentric study, DCP was scantly performed for vascular access to perform MT (0.39%) in patients with AIS-LVO and had a high rate of complications (18.5%). Our results provide arguments for not closing the cervical access by manual compression after MT.

Embolus Retriever with Interlinked Cages (ERIC) versus conventional stent retrievers for thrombectomy: a propensity score-based analysis.

BACKGROUND: The Embolus Retriever with Interlinked Cages (ERIC) is one of the latest devices for thrombectomies. It has several architectural features that are supposed to enhance its ability to remove clots and prevent distal emboli. We aimed to compare ERIC with standard stent retrievers (SRs) using propensity score (PS) matching. METHODS: The clinical and radiological data of all consecutive patients treated with ERIC or standard FDA-approved stent retrievers were collected from a prospective multicenter registry. We compared procedural outcomes (recanalization rates according to the modified Thrombolysis In Cerebral Infarction (mTICI) score and procedural complications) and clinical outcomes (modified Rankin Scale (mRS) and mortality at 3 months). Matching of the populations with PS was performed to account for differences in baseline characteristics. RESULTS: A total of 1230 patients were included. In both the PS-matched cohort (195 ERIC patients, 630 SR patients) and the inverse probability of treatment weighting PS-adjusted cohort (206 ERIC patients, 1024 SR patients) there was no difference in terms of successful recanalization (modified TICI score ≥2b), good clinical outcome (mRS=0-2 or equal to pre-stroke mRS), or mortality at 3 months. Patients treated with first-line ERIC had a higher rate of complete recanalization (mTICI 3); however, they also required more passes and more frequent rescue therapy than the SR patient group. CONCLUSION: In a large multicenter registry with PS matching, the ERIC device provided equivalent angiographic and clinical results to conventional SRs. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov Unique identifier: NCT03776877.

Genome-wide association study of intracranial aneurysms identifies 17 risk loci and genetic overlap with clinical risk factors.

Rupture of an intracranial aneurysm leads to subarachnoid hemorrhage, a severe type of stroke. To discover new risk loci and the genetic architecture of intracranial aneurysms, we performed a cross-ancestry, genome-wide association study in 10,754 cases and 306,882 controls of European and East Asian ancestry. We discovered 17 risk loci, 11 of which are new. We reveal a polygenic architecture and explain over half of the disease heritability. We show a high genetic correlation between ruptured and unruptured intracranial aneurysms. We also find a suggestive role for endothelial cells by using gene mapping and heritability enrichment. Drug-target enrichment shows pleiotropy between intracranial aneurysms and antiepileptic and sex hormone drugs, providing insights into intracranial aneurysm pathophysiology. Finally, genetic risks for smoking and high blood pressure, the two main clinical risk factors, play important roles in intracranial aneurysm risk, and drive most of the genetic correlation between intracranial aneurysms and other cerebrovascular traits.

Inter- and intraobserver reliability for angiographic leptomeningeal collateral flow assessment by the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) scale.

BACKGROUND: The adequacy of leptomeningeal collateral flow has a pivotal role in determining clinical outcome in acute ischemic stroke. The American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) collateral score is among the most commonly used scales for measuring this flow. It is based on the extent and rate of retrograde collateral flow to the impaired territory on angiography. OBJECTIVE: To evaluate inter- and intraobserver agreementin angiographic leptomeningeal collateral flow assessment. MATERIALS AND METHODS: Thirty pretreatment angiogram video loops (frontal and lateral view), chosen from the randomized controlled trial THRombectomie des Artères CErebrales (THRACE), were sent for grading in an electronic file. 19 readers participated, including eight who had access to a training set before the first grading. 13 readers made a double evaluation, 3 months apart. RESULTS: Overall agreement among the 19 observers was poor (κ = 0,16 ± 6,5.10 -3), and not improved with prior training (κ = 0,14 ± 0,016). Grade 4 showed the poorest interobserver agreement (κ=0.18±0.002) while grades 0 and 1 were associated with the best results (κ=0.52±0.001 and κ=0.43±0.004, respectively). Interobserver agreement increased (κ = 0,27± 0,014) when a dichotomized score, 'poor collaterals' (score of 0, 1 or 2) versus 'good collaterals' (score of 3 or 4) was used. The intraobserver agreements varied between slight (κ=0.18±0.13) and substantial (κ=0.74±0.1), and were slightly improved with the dichotomized score (from κ=0.19±0.2 to κ=0.79±0.11). CONCLUSION: Inter- and intraobserver agreement of collateral circulation grading using the ASITN/SIR score was poor, raising concerns about comparisons among publications. A simplified dichotomized judgment may be a more reproducible assessment when images are rated by the same observer(s) in randomized trials.

Is bridging therapy still required in stroke due to carotid artery terminus occlusions?

INTRODUCTION: Studies comparing endovascular stroke treatment using mechanical thrombectomy (MT) with or without prior IV tissue plasminogen activator (tPa) have included only 30% of internal carotid artery terminus occlusions (ICA-O), a known predictor of recanalization failure with IV tPa. OBJECTIVE: To carry out a retrospective multicenter analysis of prospectively collected data of consecutive patients to investigate the impact of intravenous thrombolysis on ICA-O by comparing patients treated with MT alone or bridging therapy (BT). MATERIAL AND METHODS: Patients with ICA-O treated with MT alone or BT were retrospectively examined and compared. Demographic data, vascular risk factors, treatment modalities, complications, technical and clinical outcomes were recorded. A propensity score (PS) analysis was used to compare modified Rankin Scale (mRS) score at 3 months and intracerebral hemorrhage (ICH) between groups. RESULTS: 141 consecutive patients (60% BT/40% MT) were included between January 2014 and June 2016. Baseline characteristics did not differ between the groups. There was no significant difference in the rate of Thrombolysis in Cerebral Infarction 2b/3, distal emboli, and median number of passes between the groups. There was a significant difference between BT and MT groups in the median time between imaging and groin puncture (median 97 min vs 75, p=0.007), the rate of ICH (44% vs 27%, p=0.05), but not for symptomatic ICH (18% vs 13%, p=0.49). With PS, there was a trend towards a higher rate of ICH (OR=2.3, 95% CI 0.9 to 5.9, p=0.09) in the BT group compared with the MT alone group, with no difference in mRS score ≤2 at 3 months (OR=1.6, 95% CI 0.7 to 3.7, p=0.29). CONCLUSION: There was no significant difference in clinical outcomes between patients receiving bridging therapy versus direct thrombectomy. Bridging therapy delayed time to groin puncture and increased ICH rate.

Mechanical thrombectomy with the ERIC retrieval device: initial experience.

OBJECTIVE: To report our experience with the Embolus Retriever with Interlinked Cage (ERIC) stentriever for use in mechanical endovascular thrombectomy (MET). METHODS: Thirty-four consecutive patients with acute stroke (21 men and 13 women; median age 66 years) determined appropriate for MET were treated with ERIC and prospectively included over a 6-month period at three different centers. The ERIC device differs from typical stentrievers in that it is designed with a series of interlinked adjustable nitinol cages that allow for fast thrombus capture, integration, and withdrawal. The evaluated endpoints were successful revascularization (Thrombolysis in Cerebral Infarction (TICI) 2b-3) and good clinical outcomes at 3 months (modified Rankin Scale (mRS) 0-2). RESULTS: Locations of the occlusions included the middle cerebral artery (13 patients), terminal carotid artery (11 patients), basilar artery (1 patient), and tandem occlusions (9 patients). IV thrombolysis was performed in 20/34 (58.8%) patients. Median times from symptom onset to recanalization and from puncture to recanalization were 325.5 min (180-557) and 78.5 min (14-183), respectively. Used as the first-line device, ERIC achieved a successful recanalization in 20/24 (83.3%) patients. Successful recanalization was associated with lower National Institutes of Health Stroke Scale scores at 24 h (8±6.5 vs 21.5±2.1; p=0.008) and lower mRS at 3 months (2.7±2.1 vs 5.3±1.1; p=0.04). Three procedural complications and four asymptomatic hemorrhages were recorded. Good clinical outcomes at 3 months were seen in 15/31 (48.4%) patients. CONCLUSIONS: The ERIC device is an innovative stentriever allowing fast, effective, and safe MET.