Renieri, Leonardo

Abstract Purpose Although the Woven EndoBridge (WEB) device is increasingly used for the treatment of wide-neck intracranial aneurysms, including in the acute rupture setting, comparative evidence assessing the impact of rupture status remains limited. This study compared angiographic, safety, and clinical outcomes between ruptured and unruptured intracranial aneurysms treated with WEB. Methods We conducted a retrospective analysis of prospectively collected data from the multicenter cohort registry WorldWideWEB, including consecutive adult patients with intracranial aneurysms treated with the WEB. Patients were stratified into groups of ruptured and unruptured aneurysms. Propensity score matching was used to balance baseline characteristics between both groups. Retreatment rate was the primary outcome. Secondary outcomes included mRS, safety events (thromboembolic complications) and angiographic outcomes (periprocedurally and last follow-up). Results Among 1,220 patients, 342 (28.0%) presented with ruptured aneurysms. There was no significant difference in the rate of thromboembolic complications between groups (11.8% vs 5.9%, p = 0.056). At follow-up, adequate occlusion was lower (82.2% vs 93.3%, p < 0.002) and functional outcomes were worse (mRS ≥2 in 34.1% vs 21.9%, p = 0.012) among patients with ruptured aneurysms. Periprocedural adequate occlusion (53.3% vs 53.8%, p>0.9) and retreatment rates (11.8% vs 7.1%, p = 0.14) did not differ between groups after matching. Conclusion Ruptured aneurysms demonstrated expected inferior follow-up functional and angiographic outcomes when compared with unruptured aneurysms, but no difference in retreatment rate and procedural safety. These findings support WEB as a safe and effective treatment option for appropriately selected ruptured intracranial aneurysms in routine clinical practice.

Background The Woven EndoBridge (WEB) device represents an innovative solution for cerebral aneurysm occlusion, particularly for challenging wide-neck bifurcation aneurysms. However, factors affecting sustained occlusion remain poorly understood. We utilized machine learning to attempt to identify predictors of favorable long-term outcomes following WEB treatment. Methods In this multicenter retrospective study, we collected patient demographics, aneurysm characteristics, procedural details, and clinical outcomes. The primary endpoint was improvement in occlusion status, defined as maintained Raymond-Roy Occlusion Classification (RROC) grade 1, or improvement from grade 2 to 1, or from grade 3 to either 2 or 1 on final angiographic follow up. The dataset was split into training (75%) and validation (25%) sets. The CatBoost algorithm was selected based on performance metrics, with Shapley Additive exPlanations (SHAP) values calculated to determine feature importance. Furthermore, a multivariable binomial logistic regression model was performed to validate machine learning findings. Results Among 720 aneurysms from 36 hospitals, 84% showed improvement in occlusion at follow up. Both machine learning and multivariable logistic regression identified aneurysm height as the most consistent correlate of nonimprovement (odds ratio (OR) 0.90 per mm, p = 0.022). In the CatBoost model, the highest-ranking features by SHAP included aneurysm height, patient age, treatment acuity, ACom location, WEB-SLS device, bifurcation anatomy, aneurysm multiplicity, baseline modified Rankin Scale, access route, and partial thrombosis. Conclusions Machine-learning and regression analyses identified consistent predictors of occlusion improvement after WEB treatment, with aneurysm height most strongly linked to nonimprovement. These insights may guide patient selection and follow up. Findings require cautious interpretation and external validation in larger cohorts.

Background: Patients with acute ischemic stroke secondary to distal and medium vessel occlusion (AIS-DMVO) and minor strokes present a challenge in determining the most appropriate emergent treatment. Factors leading to early neurological deterioration (END) in this patient population are understudied, but END is known to result in poor functional outcomes. Therefore, we aimed to investigate the factors contributing to END in minor AIS-DMVO cases. Methods: We included patients with AIS-DMVO and minor strokes from 37 sites across North America, Asia, and Europe. Minor stroke was defined as a baseline National Institutes of Health Stroke Scale (NIHSS) score of ⩽5. The primary outcome measure, END, was defined as a shift of ⩾4 points in the NIHSS score at day one after treatment compared to baseline. Univariable and multivariable logistic regression analyses were performed to identify factors associated with END. Results: Among 559 consecutive patients with DMVO and minor strokes, END was reported in 68 patients. In multivariable analysis, mechanical thrombectomy (MT) was independently associated with higher odds of END (adjusted odds ratio [aOR] 2.37, 95% CI 1.12–5.02, p = 0.02), while intravenous thrombolysis (IVT) was associated with lower odds of END (aOR 0.46, 95% CI 0.26–0.81, p = 0.008). However, the association between MT and END was no longer statistically significant in the IPTW-adjusted analysis (OR 1.65, 95% CI 0.69–3.98, p = 0.26). Hypertension and antiplatelet use at baseline were also independently associated with END. Among MT-treated patients, successful and excellent recanalization and first-pass effect were protective against END. Conclusion: MT was associated with END in patients with minor AIS-DMVO, although this association was not significant after IPTW adjustment. IVT was independently associated with reduced risk of END. These findings support careful patient selection and further study in randomized trials.

Objective Mechanical thrombectomy (MT) is well-established for the treatment of acute ischemic stroke (AIS) from large vessel occlusion (LVO), with growing data supporting the expansion to distal and medium vessel occlusions (DMVO). Despite successful recanalization in DMVO, certain patients still experience poor long-term clinical outcomes, prompting our study to comprehensively explore pre-MT factors influencing outcome despite excellent recanalization (final modified Thrombolysis in Cerebral Infarction [mTICI] score ≥2c). Methods We retrospectively examined data from patients who consecutively underwent MT for a primary middle cerebral artery (MCA) DMVO across 37 centers in North America, Asia, and Europe. We identified baseline clinical and imaging factors associated with poor clinical outcome (defined as a modified Rankin Scale [mRS] score of 3–6) at 3 months, despite excellent recanalization using a multivariable model. Results Between September 2017 and July 2021, 623 patients achieved mTICI > 2b and they were included in our study. Among them, 198 (32%) experienced a poor clinical outcome (mRS 3–6). Predictors of poor clinical outcome included higher age (OR 1.05 [1.03–1.07], p < 0.001), higher NIHSS at admission (OR 1.12 [1.08–1.15], p < 0.001), higher baseline mRS (OR 1.77 [0.96–3.26], p = 0.067), and diabetes (OR 1.59 [1.01–2.48], p = 0.044). Higher ASPECTS was associated with a decreased risk of poor clinical outcome (OR 0.82 [0.71–0.94], p = 0.006). Conclusion Older age, diabetes, higher baseline mRS, and NIHSS were associated with poor clinical outcome in MCA DMVO despite excellent recanalization. Conversely, a higher ASPECTS decreased the probability of such an outcome.

OBJECTIVE Mechanical thrombectomy (MT) is well established for large-vessel occlusion (LVO) strokes, but its safety in distal and medium-vessel occlusions (DMVOs) requires further investigation. This study analyzed the relationship between procedural approaches, petechial hemorrhage (PetH), and clinical outcomes in DMVO thrombectomy, with particular attention to technical considerations and the complex interplay between tissue injury and hemorrhagic complications. METHODS A retrospective cohort study was conducted on DMVO stroke patients treated with MT at 37 stroke centers worldwide from 2016 to 2024. Patients were categorized based on follow-up imaging into those with or without PetH. Four logistic regression models analyzed the association of PetH with favorable functional outcomes (modified Rankin Scale score ≤ 2) at 90 days, early neurological improvement (≥ 4-point National Institutes of Health Stroke Scale score decrease at 24 hours), all-cause mortality, and independent determinants of PetH. Adjusted odds ratios (aORs), 95% confidence intervals, and p values were reported. RESULTS Of 1428 patients, 439 (30.7%) developed PetH. Factors independently associated with PetH were multiple thrombectomy passes (aOR 1.58, 95% CI 1.21–2.06; p = 0.001), IV thrombolysis (aOR 1.31, 95% CI 1.01–1.69; p = 0.04), and the combined use of a stent retriever with aspiration as the first-line method compared with aspiration alone (aOR 1.66, 95% CI 1.15–2.38; p = 0.007). Conversely, general anesthesia (aOR 0.55, 95% CI 0.40–0.77; p < 0.001), higher Alberta Stroke Program Early CT Scores (aOR 0.76, 95% CI 0.69–0.83; p < 0.001), and successful recanalization (aOR 0.56, 95% CI 0.39–0.80; p = 0.002) were significantly associated with a lower odds of PetH. PetH was associated with a decreased odds of favorable functional outcomes (aOR 0.51, 95% CI 0.36–0.73; p < 0.001), reduced early neurological improvement (aOR 0.59, 95% CI 0.44–0.79; p < 0.001), and increased all-cause mortality (aOR 1.84, 95% CI 1.23–2.76; p < 0.001). CONCLUSIONS PetH is a frequent sequela following MT in DMVO strokes and is associated with poorer outcomes, likely reflecting underlying ischemic injury rather than direct causation. Procedural factors influence PetH risk, suggesting medical treatment as first-line therapy for DMVOs, with MT reserved for refractory cases using less aggressive approaches.

Background Endovascular therapy (EVT) for stroke due to distal or medium vessel occlusion (DMVO) is safe. Due to the distinct anatomical characteristics of DMVOs, further evaluation of EVT is crucial to determine which devices may yield better outcomes. Methods A retrospective analysis of adults with DMVO treated in 37 centers (11 countries) was queried. The primary outcome of favorable shift in 90-day modified Rankin Scale (mRS) was compared between patients treated with Trevo versus other devices on first pass using 1:1 propensity score matching (PSM) with multivariable adjustment. Secondary outcomes included the number of pass attempts, final thrombolysis in cerebral infarction (TICI) score 2b-3, symptomatic intracranial hemorrhage (sICH), improvement in National Institutes of Health Stroke Scale (NIHSS) at 24h, and 90-day mortality. Results Of the 1115 included patients, 264 (24%) were treated with Trevo (PSM cohort of 261 per group). Trevo use was not associated with a favorable 90-day mRS shift (proportional odds ratio [OR] 1.10, 95% confidence interval [CI] 0.80–1.51). Trevo was associated with fewer passes (adjusted β=-0.25, 95% CI −0.48 - −0.03), higher odds of TICI 2b-3 (adjusted OR 1.97, 95% CI 1.11–3.49), and a greater 24h NIHSS improvement (adjusted β= −1.74, 95% CI −3.11 - −0.36), with no difference in sICH or mortality (p>0.05). Results were similar in sensitivity analyses. Conclusions We observed no safety concerns with Trevo as compared to other EVT devices for DMVO recanalization. There was a signal of better technical efficacy and early clinical improvement.

Background The Woven EndoBridge (WEB) device is a prevalent treatment for intracranial aneurysms. While many studies have assessed the obliteration rate post-WEB embolization, few have focused on long-term outcomes in partially thrombosed aneurysms. Objective To assess whether partially thrombosed aneurysms are at higher risk of recurrence or retreatment following WEB embolization compared with non-thrombosed aneurysms. Methods We evaluated data from 22 academic institutions, focusing on previously untreated cerebral aneurysms treated with the WEB device. Logistic regression was utilized to analyze factors predicting long-term aneurysm obliteration and retreatment necessity. Results Among 1303 patients, 26 presented with a partially thrombosed aneurysm. In the partially thrombosed group, the mean aneurysm maximal diameter was 10.7±4 mm with a neck ratio of 1.99±1.19 mm, larger than in the control group where the mean aneurysm maximal diameter was 6.81±2.37 mm with a neck ratio of 1.64±0.51 mm (P<0.001 for both maximal diameter and neck ratio). At the final follow-up, partially thrombosed aneurysms treated by the WEB device had a 38.5% retreatment rate, compared with 7.0% for non-thrombosed aneurysms (P<0.001). Among partially thrombosed aneurysms, the Raymond-Roy type IIIa/b occlusion rate was higher (38.5% vs 9.9%, P<0.001). On multivariate analysis, partially thrombosed aneurysms compared with non-thrombosed aneurysms had an increased rate of retreatment (OR 3.64, 95% CI 1.28 to 10.1). Conclusion Partially thrombosed aneurysms are associated with a poorer occlusion rate and a higher rate of retreatment following WEB embolization. For partially thrombosed aneurysms, the WEB device appears suboptimal as a first-line treatment, and therefore alternative techniques should be prioritized.

Background Flow-diverter stents (FDS) have become the standard of care for a wide range of intracranial aneurysms, but their efficacy/safety in the context of recurrent/recanalized aneurysms following stent-assisted coiling (SAC) is not well established. We evaluate the outcomes of FDS retreatment in a large multicenter cohort. Methods We retrospectively analyzed data from 118 patients across 22 institutions who underwent FDS retreatment for recurrent/persistent aneurysms after SAC (2008–22). The primary outcome was angiographic occlusion status at last follow-up, categorized as complete (100%), near-complete (90–99%), or incomplete (<90%) occlusion. Secondary outcomes included procedural complications and clinical outcomes measured by the modified Rankin Scale (mRS). Results A total of 118 patients (median age 57, 74.6% female) with median follow-up of 15.3 months were identified. Complete occlusion was achieved in 62.5% and near-complete occlusion in 25%. FDS deployment within the pre-existing stent was successful in 98.3% of cases. Major complications occurred in 3.4% of cases, including postoperative aneurysmal rupture with resultant mortality (1.6%) and thromboembolic events with long-term disability (1.6%). Favorable clinical outcomes (mRS 0–2) were observed in 95.1% of patients. Wider aneurysm neck diameter was a significant predictor of incomplete occlusion (adjusted OR (aOR) 1.23 per mm, P=0.044), with male sex trending towards association with non-occlusion (aOR 3.2, P=0.07), while baseline hypertension was associated with complete occlusion (aOR 0.32, P=0.048). Conclusions FDS treatment for recurrent/residual aneurysms after SAC represents a viable treatment option for these challenging cases with acceptable safety and reasonable occlusion rates, although lower than de novo FDS occlusion rates.

Background Mechanical thrombectomy (MT) is established as an effective treatment for large vessel occlusion strokes, but its efficacy and safety for medium vessel occlusions (MeVOs) remain less clear. This study examines the impact of periprocedural embolization to a new vascular territory (ENT) on clinical outcomes in patients with MeVO stroke treated with MT. Methods A multicenter, retrospective analysis was conducted using the MAD-MT (Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy) registry, including 2122 patients with MeVO stroke w­ho underwent MT between September 2017 and July 2023. ENT was defined as filling defects in previously unaffected territories, excluding embolization near the original occlusion, observed on final angiographic runs after retrieval of the primary thrombus. The associations between ENT, procedural variables, and 90-day clinical outcomes were evaluated, including functional independence (modified Rankin Scale (mRS) scores of 0–2), excellent outcomes (mRS 0–1), mortality, and hemorrhagic complications. Results ENT occurred in 2.9% (63/2122) of patients. Longer onset-to-arterial puncture time (adjusted OR 1.03; 95% CI 1.01 to 1.05; P=0.002) and a greater number of passes (adjusted OR 1.15; 95% CI 1.01 to 1.32; P=0.032) were associated with increased ENT risk, while excellent recanalization (thrombolysis in cerebral infarction (TICI) scale score 2c–3) was associated with reduced ENT risk (adjusted OR 0.41; 95% CI 0.23 to 0.72; P=0.002). ENT was not associated with poorer functional independence, mortality, or hemorrhagic complications. Conclusions ENT during MT for MeVO stroke occurs infrequently and does not significantly affect the clinical outcomes. These findings suggest ENT risk should not deter clinicians from performing MT in patients with MeVO. Further prospective studies are needed to validate these results.

OBJECTIVE Tobacco smoking is among the factors known to significantly augment the risk of untreated intracranial aneurysm (IA) growth and rupture. Smoking appears to have a variable effect on different endovascular treatment modalities. The impact of smoking on the safety, efficacy, and outcomes of Woven EndoBridge (WEB) device use for wide-neck IAs has not been evaluated. This study aimed to investigate the outcomes of WEB devices by smoking status. METHODS A retrospective multicenter analysis was conducted on the data of patients from 36 sites worldwide treated with the WEB device for intracranial saccular aneurysms. Patients were stratified based on smoking status (current, former, and never smokers). The Student t-test and chi-square test were performed for continuous and categorical variables, respectively. Multivariable logistic regression was used to adjust for confounders. RESULTS Of 1376 patients with available smoking status, 504 were current smokers, 358 were former smokers, and 514 were never smokers. Upon adjusting for significant confounders, no association was found between smoking and recurrence outcomes (OR 1.39, 95% CI 0.69–2.80; p = 0.36), thromboembolic and hemorrhagic complications, and mortality among IAs treated with the WEB device. There was no statistically significant difference in outcomes between former and never smokers (OR 1.23, 95% CI 0.70–2.18; p = 0.46). The location of aneurysms differed between smoking groups, with former smokers having more anterior circulation aneurysms compared with current and never smokers (99.0% vs 96.9% vs 95.3%; p = 0.01). In terms of clinical symptoms, headache and dizziness were more common in the never smokers compared with current and former smokers (13.9% vs 8.9% vs 7.7%, p = 0.01). CONCLUSIONS This large-scale study suggests no significant correlation between smoking and the recurrence of IAs treated with the WEB device. Biological studies are warranted to better understand the biological impact of smoking on the growth and rupture of treated IAs.