Kan, Peter

Introduction: While balloon guide catheters (BGCs) enhance safety and efficacy of mechanical thrombectomy in large vessel occlusions, their impact on distal medium vessel occlusion (DMVO) remains underexplored. This study aimed to compare the outcomes of BGC vs non-BGC in DMVO thrombectomy. Methods: This retrospective study focused on DMVO cases defined as occlusions in M2-M4 middle cerebral artery, anterior cerebral artery, and posterior cerebral artery. Baseline characteristics and technical and clinical outcomes were compared between the two groups, with subgroup analysis in first-line thrombectomy techniques, including ADAPT, stent retriever, and Solumbra. First pass effect (FPE) was defined as a modified Thrombolysis in Cerebral Infarction (mTICI) score ≥ 2C after the first pass. Results: A total of 1,508 patients were included, of whom 231 (15.3%) were in the BGC group and 1,277 (84.7%) were in the Non-BGC group. The BGC group was associated with a lower mTICI score ≥ 2C (overall: 43.2% vs. 52.7%, p = 0.01; ADAPT: 42.2% vs. 57.1%, p = 0.01; Solumbra: 32.4% vs. 51.4%, p = 0.005), longer puncture to intracranial access time (overall: 15 vs. 8 min, p < 0.001; ADAPT: 17 vs. 8 min, p < 0.001; Solumbra: 12 vs. 8 min, p = 0.02), and longer puncture to recanalization time (overall: 97 vs. 35 min, p < 0.001; ADAPT: 100 vs. 28 min, p < 0.001; Solumbra: 78 vs. 46 min, p < 0.001; Stent retriever: 95 vs. 45 min, p < 0.001 ). The BGC group also had a lower FPE rate (17.4% vs. 30.7%, p = 0.03) in the Solumbra subgroup. In terms of clinical outcomes, the BGC group had a lower rate of distal embolization (overall: 8.8% vs. 14.9%, p = 0.02), but there were no significant differences in other clinical outcomes between the two groups in first-line thrombectomy techniques. Conclusions: Our findings showed that the use of BGC in DMVO had a lower mTICI score, reduced FPE rates, decreased distal embolization, and longer procedure times. Figure 1: Figure 2:

Introduction: The efficacy of mechanical thrombectomy (MT) for tandem vertebrobasilar occlusion (tVBO) is not well established in patients with basilar artery occlusion (BAO). Objective: To investigate the treatment outcomes of MT in tVBO. Method: This international, multicenter, retrospective cohort included patients with MT for tVBO and isolated BAO from 2013 to 2023. The primary outcome was the 90-day modified Rankin Scale (mRS) score 0-2. Secondary outcomes included complete recanalization (modified Thrombolysis in Cerebral Ischemia [mTICI] ≥ 2C) and 90-day mortality rate. These outcomes were compared between tVBO and isolated BAO groups. Adjustment factors were age, sex, admission National Institutes of Health Stroke Scale (NIHSS), pre-morbid mRS, onset to groin duration, and intravenous tissue plasminogen activator. Results: Among 10,229 patients, 689 had BAO. Of those, 61 (9.7%) had a tVBO. Median age was 61 [IQR 53-74] years and 29 (47.5%) patients were female. Compared to isolated BAO, tVBO group had lower age (61 [53-74] versus 68 [58-79], P<0.001) and lower admission NIHSS (15 [7 - 22] versus 17 [9-26], P≤0.05). There was no significant difference in the rate of complete recanalization between the two groups (adjusted odds ratio [aOR]: 0.83; 95% CI: 0.39-1.79; P=0.60) However, the tVBO group had significantly lower odds of a favorable outcome compared to the isolated BAO group (aOR: 0.35; 95% CI: 0.13-0.83; P=0.023) and higher odds of 90-day mortality (aOR: 3.51; 95% CI: 1.59-7.85; P=0.002). Binary regression analysis revealed that age (OR 0.98; 95% CI 0.96 - 1.00; P=0.019), admission NIHSS (OR 0.90; 95% CI 0.87-0.93; P<0.001), premorbid mRS (OR 0.71; 95% CI 0.53-0.93; P=0.016), successful recanalization (OR 2.94; 95% CI 1.71-5.15; P<0.001), and tVBO (OR 0.33; 95% CI 0.11-0.86; P=0.031) were significant predictors of 90-day favorable outcome. Conclusion: tVBO was associated with poor outcomes. Further efforts should be aimed at improving outcomes for this subpopulation.

Objective: To determine whether first pass effect (FPE) after mechanical thrombectomy (MT) for anterior circulation large vessel occlusion acute ischemic stroke (LVO-AIS) is modified by procedural time (PT). Methods: The Stroke Thrombectomy and Aneurysm Registry (STAR), a multi-center international dataset, was retrospectively analyzed for anterior circulation LVO-AIS treated by MT who achieved excellent reperfusion (TICI 2c/3). The primary outcome was good functional outcome as defined by a 90-day modified Rankin Scale (mRS) 0-2. The primary study exposure was first pass success (FPS, 1 pass vs ≥2 passes) and the secondary exposure was PT. Logistic regression models were fit-adjusted and marginal effects used to assess the interaction of PT (≤30 vs >30 minutes) and FPS, adjusting for potential confounders including time from last known well to start of MT. Results: A total of 1,310 patients had excellent reperfusion. These patients were divided into two cohorts based on PT: ≤30 minutes (777 patients, 59.3%) and > 30 minutes (533 patients, 40.7%). Good functional outcome was observed in 658 patients (50.2%). The interaction term between FPS and PT was significant (p=0.018). Individuals with FPS in ≤30 minutes had 11.5% higher adjusted predicted probability of good outcome compared with those who required ≥2 passes (58.2% vs. 46.7%, p=0.001). However, there was no significant difference in the adjusted predicted probability of good outcome based on FPS in individuals with PT >30 minutes (p=0.763). This relationship appeared identical in models with PT treated as a continuous variable. Conclusion: In a large, real-world, multi-national dataset, we find that FPE is importantly modified by PT. The added clinical benefit of FPE is lost in longer procedures (>30 minutes). These data argue for a new metric for MT procedures, namely, FPE 30 , that better represents the ideal of fast, complete reperfusion with a single pass of a thrombectomy device.

Background As the number of thrombectomy passes increases during endovascular therapy (EVT) for acute stroke, neurointerventionalists must weigh the risks of potential complications against the risk of failing to recanalize the affected vessel. Thus, we investigated the effectiveness and safety of EVT for patients with acute stroke in which ≥5 EVT passes were performed. Methods This retrospective cohort study from January 2013 to December 2022 included 31 thrombectomy‐capable centers. Patients in whom ≥5 EVT passes were made were included in the analysis. The patients with successful recanalization defined as modified Thrombolysis in Cerebral Infarction ≥2b at 5, 6, 7, or more passes were compared with unsuccessful recanalization. We also compared procedure time, separated by 30 minutes. Primary outcome was a favorable 90‐day outcome (modified Rankin scale score of 0–2). Secondary outcomes were intracranial hemorrhage and death. Results A total of 407 patients met the inclusion criteria, of which 175 were women (43.1%); the mean age was 67.3 years. In 265 (65.1%) patients, successful recanalization was achieved: 134 patients with 5 passes, 67 patients with 6 passes, and 64 with ≥7 passes. Intravenous recombinant tissue plasminogen activator administration was more common in the unsuccessful recanalization group (successful recanalization with 5, 6, and ≥7 EVT passes and unsuccessful recanalization: 35.3%, 30.3%, 18.8%, and 45.4%, respectively). Successful recanalization with 5, 6, and ≥7 EVT passes was associated with favorable outcome compared with unsuccessful recanalization group (adjusted odds ratio successful recanalization with 5, 6, and ≥7 EVT passes to unsuccessful recanalization [95% CIs]: 8.29 [2.13–32.3]; 14.0 [3.27–60.3]; and 5.26 [1.12–24.8], respectively). However, symptomatic intracranial hemorrhage was not significantly different between the groups. Regarding procedure time, favorable outcome was not significantly different in each group, while symptomatic intracranial hemorrhage occurred more frequently in the 60 to 89 minutes group compared with the <30 minutes group (adjusted odds ratio, 60–89 minutes group to <30 minutes group [95% CI]: 5.86 [1.09–31.6]). Conclusion These findings suggest that a benefit in outcome persists for recanalization, without significant increase in complications. In addition, there was no significant difference in favorable outcomes among procedure time.

OBJECTIVE The Woven EndoBridge (WEB) device is an intrasaccular flow disruptor designed for wide-necked bifurcation aneurysms. These aneurysms may require the use of a concomitant stent. The objective of this study was to determine the clinical and radiological outcomes of patients undergoing stent-assisted WEB treatment. In addition, the authors also sought to determine the predictors of a concomitant stent in aneurysms treated with the WEB device. METHODS The data for this study were taken from the WorldWideWEB Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups based on treatment: stent-assisted WEB and WEB device alone. The authors compared clinical and radiological outcomes of both groups. Univariable and multivariable binary logistic regression analyses were performed to determine factors that predispose to stent use. RESULTS The study included 691 intracranial aneurysms (31 with stents and 660 without stents) treated with the WEB device. The adequate occlusion status did not differ between the two groups at the latest follow-up (83.3% vs 85.6%, p = 0.915). Patients who underwent stenting had more thromboembolic (32.3% vs 6.5%, p < 0.001) and procedural (16.1% vs 3.0%, p < 0.001) complications. Aneurysms treated with a concomitant stent had wider necks, greater heights, and lower dome-to-neck ratios. Increasing neck size was the only significant predictor for stent use. CONCLUSIONS This study demonstrates that there is no difference in the degree of aneurysm occlusion between the two groups; however, complications were more frequent in the stent group. In addition, a wider aneurysm neck predisposes to stent assistance in WEB-treated aneurysms.

Background For acute proximal intracranial artery occlusions, contact aspiration may be more effective than stent‐retriever for first‐line reperfusion therapy. Due to the lack of data regarding medium vessel occlusion thrombectomy, we evaluated outcomes according to first‐line technique in a large, multicenter registry. Methods Imaging, procedural, and clinical outcomes of patients with acute proximal medium vessel occlusions (M2, A1, or P1) or distal medium vessel occlusions (M3, A2, P2, or further) treated at 37 sites in 10 countries were analyzed according to first‐line endovascular technique (stent‐retriever versus aspiration). Multivariable logistic regression and propensity‐score matching were used to estimate the odds of the primary outcome, expanded Thrombolysis in Cerebral Infarction score of 2b–3 (“successful recanalization”), as well as secondary outcomes (first‐pass effect, expanded Thrombolysis in Cerebral Infarction 2c‐3, intracerebral hemorrhage, and 90‐day modified Rankin scale, 90‐day mortality) between treatment groups. Results Of the 440 included patients (44.5% stent‐retriever versus 55.5% aspiration), those treated with stent‐retriever had lower baseline Alberta Stroke Program Early Computed Tomography Scale scores (median 8 versus 9; P <0.01), higher National Institutes of Health Stroke Scale scores (median 13 versus 11; P =0.02), and nonsignificantly fewer medium‐distal occlusions (M3, A2, P2, or other: 17.4% versus 23.8%; P =0.10). Use of a stent‐retriever was associated with 15% lower odds of successful recanalization (odds ratio [OR], 0.85; [95% CI 0.74–0.98]; P =0.02), but this was not significant after multivariable adjustment in the total cohort (adjusted OR, 0.88; [95% CI 0.72–1.09]; P =0.24), or in the propensity‐score matched cohort (n=105 in each group) (adjusted OR, 0.94; [95% CI 0.75–1.18]; P =0.60). There was no significant association between technique and secondary outcomes in the propensity‐score matched adjusted models. Conclusion In this large, diverse, multinational medium vessel occlusion cohort, we found no significant difference in imaging or clinical outcomes with aspiration versus stent‐retriever thrombectomy.

BACKGROUND: Dural arteriovenous fistulas (dAVFs) located at craniocervical junction are extremely rare (1%-2% of intracranial/spinal dAVFs). Their angio-architectural complexity renders endovascular embolization to be challenging given multiple small feeders with risk of embolysate reflux into vertebral artery and limited transvenous access. The available literature discussing microsurgery for these lesions is limited to few case reports. OBJECTIVE: To report a multicenter experience assessing microsurgery safety/efficacy. METHODS: Prospectively maintained registries at 13 North American centers were queried to identify craniocervical junction dAVFs treated with microsurgery (2006-2021). RESULTS: Thirty-eight patients (median age 59.5 years, 44.7% female patients) were included. The most common presentation was subarachnoid/intracranial hemorrhage (47.4%) and myelopathy (36.8%) (92.1% of lesions Cognard type III-V). Direct meningeal branches from V3/4 vertebral artery segments supplied 84.2% of lesions. All lesions failed (n = 5, 13.2%) or were deemed inaccessible/unsafe to endovascular treatment. Far lateral craniotomy was the most used approach (94.7%). Intraoperative angiogram was performed in 39.5% of the cases, with angiographic cure in 94.7% of cases (median imaging follow-up of 9.2 months) and retreatment rate of 5.3%. Favorable last follow-up modified Rankin Scale of 0 to 2 was recorded in 81.6% of the patients with procedural complications of 2.6%. CONCLUSION: Craniocervical dAVFs represent rare entity of lesions presenting most commonly with hemorrhage or myelopathy because of venous congestion. Microsurgery using a far lateral approach provides robust exposure and visualization for these lesions and allows obliteration of the arterialized draining vein intradurally as close as possible to the fistula point. This approach was associated with a high rate of angiographic cure and favorable clinical outcomes.

Background The Woven EndoBridge (WEB) device is a novel intrasaccular flow disruptor tailored for bifurcation aneurysms. We aim to describe the degree of aneurysm occlusion at the latest follow-up, and the rate of complications of aneurysms treated with the WEB device stratified according to rupture status. Methods Our data were taken from the WorldWideWeb Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups: ruptured and unruptured. We compared clinical and radiologic outcomes of both groups. Propensity score matching (PSM) was done to match according to age, gender, bifurcation, location, prior treatment, neck, height, dome width, daughter sac, incorporated branch, pretreatment antiplatelets, and last imaging follow-up. Results The study included 676 patients with 691 intracranial aneurysms (529 unruptured and 162 ruptured) treated with the WEB device. The PSM analysis had 55 pairs. In both the unmatched (85.8% vs 84.3%, p=0.692) and matched (94.4% vs 83.3%, p=0.066) cohorts there was no significant difference in the adequate occlusion rate at the last follow-up. Likewise, there were no significant differences in both ischemic and hemorrhagic complications between the two groups. There was no documented aneurysm rebleeding after WEB device implantation. Conclusion There was no significant difference in both the radiologic outcomes and complications between unruptured and ruptured aneurysms. Our findings support the feasibility of treatment of ruptured aneurysms with the WEB device.

Abstract BACKGROUND Open surgery has traditionally been preferred for the management of bifurcation middle cerebral artery (MCA) aneurysms. Flow diverting stents present a novel endovascular strategy for aneurysm treatment. OBJECTIVE To add to the limited literature describing the outcomes and complications in the use of flow diverters for the treatment of these complex aneurysms. METHODS This is a multicenter retrospective review of MCA bifurcation aneurysms undergoing flow diversion. We assessed post-treatment radiological outcomes and both thromboembolic and hemorrhagic complications. RESULTS We reviewed the outcomes of 54 aneurysms treated with flow diversion. Four (7.4%) of the aneurysms had a history of rupture (3 remote and 1 acute). Fourteen (25.9%) of the aneurysms already underwent either open surgery or coiling prior to flow diversion. A total of 36 out of the 45 aneurysms (80%) with available follow-up data had adequate aneurysm occlusion with a median follow-up time of 12 mo. There were no hemorrhagic complications but 16.7% (9/54) had thromboembolic complications. CONCLUSION Flow diverting stents may be a viable option for the endovascular treatment of complex bifurcation MCA aneurysms. However, compared to published series on the open surgical treatment of this subset of aneurysms, flow diversion has inferior outcomes and are associated with a higher rate of complications.

Abstract Carotid artery angioplasty and stenting (CAS) has been shown to be equally effective as carotid endarterectomy (CEA) for carotid stenosis in both symptomatic and asymptomatic disease. 1 In patients who are considered high risk for endarterectomy, CAS is safe and effective. 2 While this is a common procedure, proper technique is crucial to ensure that the procedure is safe with minimal risk of stroke. This patient consented to treatment. The following is a video detailing the CAS procedure in a 77-yr-old male with a symptomatic 65% carotid stenosis (by NASCET criteria 3 ) in a patient with prior CEA.