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Samaniego, Edgar A

0000-0003-2764-2268

A5051773233 | I126307644

Mayo Clinic

University of Iowa

Citations 49

Abstract 290: Treatment Strategies for Residual and Recurrent Aneurysms After Woven EndoBridge Therapy: A Multicenter Propensity‐Matched Analysis

Stroke: Vascular and Interventional Neurology | December 2, 2025 | Volume: 5 | Issue: S1 | Pages: No page available

10.1161/svi270000_290

Introduction Post‐market and multicenter studies report low complete occlusion rates (41‐49%) and higher retreatment rates (13%) following WEB deployment, compared to 3.8% with microsurgical clipping. While retreatment after WEB has been shown to be technically feasible, data on final angiographic outcomes remain limited. We performed a retrospective analysis of prospective databases from 14 cerebrovascular centers in the US to compare the safety and efficacy of retreatment versus continued observation for residual and recurrent aneurysms after initial WEB deployment. Materials/Methods Multinomial logistic regression was used to identify baseline characteristics of untreated and residual/recurrent aneurysms that may act as confounders, which then underwent propensity scored matching (PSM). Results Among 211 patients (125 observed, 86 retreated), retreatment was more common in initially ruptured aneurysms (p<0.001), which showed higher recurrence (p=0.036) and sac‐dominant residuals (p=0.004). These were primarily due to WEB compression on follow‐up (p=0.001), rather than incomplete occlusion with an appropriately sized device (p<0.001). Retreatment was associated with significantly higher rates of complete angiographic occlusion at last follow‐up compared to observation alone (p<0.001), a finding that remained consistent across subgroups defined by initial unruptured status, residual type, and recurrence patterns (all p<0.05). Clipping demonstrated higher, though statistically insignificant, rates of complete occlusion; flow diversion and stent‐assisted coil embolization yielded comparable complete occlusion rates at follow‐up. After propensity score matching, retreatment remained significantly associated with higher rates of complete angiographic occlusion (all p<0.05), with comparable outcomes observed between clipping and various endovascular approaches as above. Conclusion Retreatment improved complete occlusion rates; however, no aneurysmal hemorrhages occurred in either group. Further intervention may be unnecessary when the WEB device—whether compressed or intact (BOSS 0/1)—adequately protects the dome. In cases where WEB compression significantly exposes the aneurysm wall, stent‐assisted coiling or flow diversion can be performed safely and successfully, depending on vascular anatomy and surgeon preference. image image
Procedure duration predicts outcomes more than prehospital delay in endovascular stroke treatment

Journal of NeuroInterventional Surgery | September 19, 2025 | Volume: 18 | Issue: 6 | Pages: 1494-1502

10.1136/jnis-2025-023906 | PMID 40973492

Background Endovascular thrombectomy (EVT) has transformed acute ischemic stroke (AIS) care, with onset-to-puncture (OTP) time widely recognized as a critical determinant of outcome. However, emerging evidence suggests that in-hospital procedure time (PT)—from arterial puncture to final recanalization—may have an equally or more significant impact. This study examines the relative contribution of PT versus OTP to functional outcomes in patients with AIS undergoing EVT. Methods A retrospective analysis was conducted of 6644 patients with AIS treated at 44 international stroke centers from the Stroke Thrombectomy and Aneurysm Registry (STAR; 2016–2023). Multivariable regression, time-equivalence analysis, and marginal effects modeling were used to assess associations between PT, OTP, and 90-day modified Rankin Scale (mRS) outcomes. Centers were stratified by procedural efficiency and compared using propensity score matching (PSM). Mediation analysis evaluated whether PT accounted for inter-center differences. Results PT and OTP were independently associated with functional outcomes; however, PT had a significantly stronger effect (adjusted OR for mRS 0–2: PT=0.56 vs OTP=0.96 per hour). Each 5 min increase in PT was equivalent to 78–100 min of additional OTP in outcome impact. Centers with faster average PT had higher rates of functional independence (number needed to treat (NNT)=10), fewer complications, and lower symptomatic intracranial hemorrhage rates. PT significantly mediated the relationship between center tier and outcomes (Sobel’s P<0.001). Conclusion While minimizing OTP remains important, PT exerts a greater influence on outcomes after EVT. Procedural efficiency should be emphasized in stroke systems of care and included in center performance metrics to improve patient outcomes.
Conventional versus advanced imaging selection for endovascular treatment of basilar artery occlusion strokes

European Stroke Journal | August 28, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/23969873251364973 | PMID 40873294

Introduction: Endovascular thrombectomy (EVT) is an effective treatment for basilar artery occlusion (BAO) stroke in select patients. While there is a growing body of literature suggesting that advanced imaging modalities such as computed tomography perfusion (CTP) and magnetic resonance (MR) may not be necessary for selecting anterior circulation large vessel occlusion stroke patients for EVT, whether advanced imaging may be superior to conventional imaging (non-contrast CT and CT angiography) in identifying good treatment candidates among BAO patients is less clear. Patients and methods: This was a multicenter retrospective cohort study of BAO EVT patients treated from 2013 to 2022 in the Stroke Thrombectomy and Aneurysm Registry. Patients selected for EVT by advanced imaging (CTP or MR) were matched with those selected by conventional imaging using propensity score matching (PSM) accounting for possible confounders. Primary outcome was functional independence at 90 days. Other outcomes include bedridden state or death at 90-days and symptomatic intracranial hemorrhage (sICH). Results: 268 patients were included. 150 patients were selected for BAO EVT by conventional imaging, 86 by CTP, and 32 by MR. Patients selected by advanced imaging were significantly older than those selected by conventional imaging (median age 71 vs 64 years, p = 0.001); patient characteristics were otherwise similar between cohorts. After PSM, 90-day outcomes were similar between the two cohorts ( p = 0.56), with similar rates of functional independence (39.4% vs 35.1%, p = 0.65), bedridden state or death (40.4% vs 44.7%, p = 0.66), and sICH (3.3% vs 5.7%, p = 0.49) for conventional and advanced imaging groups, respectively. Results were similar across treatment time windows (all p > 0.05). Conclusions: Selecting patients for basilar EVT using conventional versus advanced imaging did not result in different clinical outcomes, regardless of treatment time windows. Conventional imaging appears sufficient as a first-line tool for selecting basilar EVT patients in routine clinical practice.
Hurting More Than Helping? Decompressive Craniectomy in Patients With Symptomatic Intracerebral Hemorrhage After Mechanical Thrombectomy in Acute Ischemic Stroke: Insights From Stroke Thrombectomy and Aneurysm Registry

Neurosurgery | June 9, 2025 | Volume: 98 | Issue: 2 | Pages: 345-357

10.1227/neu.0000000000003563 | PMID 40488514

BACKGROUND AND OBJECTIVES: It remains unclear whether decompressive craniectomy (DC) is beneficial in patients who suffer symptomatic intracerebral hemorrhage (sICH) after acute ischemic stroke (AIS). We sought to study the effect of DC on functional outcomes in patients with sICH after AIS who underwent mechanical thrombectomy (MT). METHODS: Patients with AIS from anterior circulation large vessel occlusion who underwent MT and subsequently developed sICH were identified from the Stroke Thrombectomy and Aneurysm Registry database. The primary outcome was acceptable 90-day functional neurological outcome, defined as modified Rankin scale (mRS) 0-3. Multivariable logistic regression and propensity-score matching were used to identify and quantify risk factors. RESULTS: Of 464 patients identified with sICH after AIS after MT, 97 patients (20.9%) underwent DC. Patients who underwent DC were more likely to be female ( P < .001), younger ( P < .001), have a measured medical comorbidity, have higher baseline mRS ( P = .02), and have higher-grade hemorrhages ( P = .01). At 90 days, 14% of patients had the primary outcome of mRS 0-3 and 56% had died. The primary outcome was observed in 11 patients who underwent DC (11%) and 55 (15%) of those without DC (odds ratio [OR] 0.7, 95% CI 0.4-1.4, P = .40). DC did not affect mRS shift at 90 days ( P = .10) but was associated with lower mortality (OR 0.5, 95% CI 0.3-0.8, P = .01). Multivariable analysis demonstrated that DC decreased the odds of primary outcome (adjusted OR 0.2, 95% CI 0.02-0.9, P = .045), but did not affect mortality ( P = .94), mRS shift ( P = .50), or length of stay ( P = .90). Propensity-matched analysis similarly demonstrated that non-DC patients were more likely to achieve the primary outcome (24% vs 8%, P = .045). CONCLUSION: In patients with sICH after AIS after MT, those selected for DC had less favorable outcomes and similar rates of mortality at 90 days.
Stereotactic radiosurgery versus observation for intracranial low-grade dural arteriovenous fistulas

Journal of Neurology, Neurosurgery & Psychiatry | June 6, 2025 | Volume: 96 | Issue: 11 | Pages: 1117-1125

10.1136/jnnp-2024-335675 | PMID 40480804

Background Given the low haemorrhagic risk of intracranial low-grade dural arteriovenous fistulas (dAVFs), the benefits of routine intervention remain controversial. This study compares patient outcomes treated with stereotactic radiosurgery (SRS) versus conservative management. Method Multicentre retrospective analysis of the Consortium for Dural Arteriovenous Fistula Outcomes Research and the International Radiosurgery Research Foundation data. Inclusion criteria were (1) intracranial low-grade dAVF diagnosed by catheter-based angiography, (2) no prior dAVF-related haemorrhage and (3) management with upfront SRS (intervention group) or conservative management (observation group). The primary outcome was symptomatic improvement. Secondary outcomes included dAVF obliteration, up-conversion, haemorrhage, improvement and favourable modified Rankin Scale (mRS) at follow-up. Results 304 patients with a mean age of 56 years (SD 13.5) and a follow-up of 46.7 months (SD 45.5) were included. 135 (44.4%) were managed conservatively and 169 (55.6%) had upfront SRS. Compared with the observation group, symptomatic and mRS Score improvement (≥1-point decrease in baseline score) was more likely in the intervention group (95.1% vs 58.5%; OR=13.75 (5.61–33.69) and 37.0% vs 24.0%; OR=1.85 (1.09–3.15), respectively). These findings remained significant after multiple imputation and propensity score matching. Remaining outcomes were similar between groups. The all-cause mortality rate was 5.4% (n=16), unrelated to the dAVF or treatment. Five (3.0%) SRS-related complications were reported and resolved during the follow-up period. Conclusions SRS was associated with increased symptomatic and mRS Score improvement for low-grade dAVFs compared with conservative management. SRS had a low complication risk and did not appear to alter dAVF obliteration or haemorrhage. Future prospective trials on SRS as a first-line intervention for symptomatic low-grade dAVFs should be considered.
Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection: The STOP-CAD Study

Stroke | June 4, 2025 | Volume: 55 | Issue: 4 | Pages: 908-918

10.1161/strokeaha.123.045731 | PMID 38335240

BACKGROUND: Small, randomized trials of patients with cervical artery dissection showed conflicting results regarding optimal stroke prevention strategies. We aimed to compare outcomes in patients with cervical artery dissection treated with antiplatelets versus anticoagulation. METHODS: This is a multicenter observational retrospective international study (16 countries, 63 sites) that included patients with cervical artery dissection without major trauma. The exposure was antithrombotic treatment type (anticoagulation versus antiplatelets), and outcomes were subsequent ischemic stroke and major hemorrhage (intracranial or extracranial hemorrhage). We used adjusted Cox regression with inverse probability of treatment weighting to determine associations between anticoagulation and study outcomes within 30 and 180 days. The main analysis used an as-treated crossover approach and only included outcomes occurring with the above treatments. RESULTS: The study included 3636 patients (402 [11.1%] received exclusively anticoagulation and 2453 [67.5%] received exclusively antiplatelets). By day 180, there were 162 new ischemic strokes (4.4%) and 28 major hemorrhages (0.8%); 87.0% of ischemic strokes occurred by day 30. In adjusted Cox regression with inverse probability of treatment weighting, compared with antiplatelet therapy, anticoagulation was associated with a nonsignificantly lower risk of subsequent ischemic stroke by day 30 (adjusted hazard ratio [HR], 0.71 [95% CI, 0.45–1.12]; P =0.145) and by day 180 (adjusted HR, 0.80 [95% CI, 0.28–2.24]; P =0.670). Anticoagulation therapy was not associated with a higher risk of major hemorrhage by day 30 (adjusted HR, 1.39 [95% CI, 0.35–5.45]; P =0.637) but was by day 180 (adjusted HR, 5.56 [95% CI, 1.53–20.13]; P =0.009). In interaction analyses, patients with occlusive dissection had significantly lower ischemic stroke risk with anticoagulation (adjusted HR, 0.40 [95% CI, 0.18–0.88]; P interaction =0.009). CONCLUSIONS: Our study does not rule out the benefit of anticoagulation in reducing ischemic stroke risk, particularly in patients with occlusive dissection. If anticoagulation is chosen, it seems reasonable to switch to antiplatelet therapy before 180 days to lower the risk of major bleeding. Large prospective studies are needed to validate our findings.
The effect of aspirin on aneurysm wall enhancement: A study in rabbits and humans

Interventional Neuroradiology | May 28, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15910199251341035 | PMID 40356451

Objective Aneurysm wall enhancement (AWE) is a potential biomarker of inflammation within the aneurysm wall that has been correlated with a higher risk of rupture. Aspirin (ASA) may decrease AWE due to its anti-inflammatory properties. We aimed to assess the effect of ASA on AWE in an animal model and a cohort of patients with unruptured intracranial aneurysms (UIAs). Methods Three rabbits with elastase-induced aneurysms were exposed to ASA for 8 weeks and three rabbits were used as controls. 3 T high-resolution magnetic resonance imaging (HR-MRI) was performed at 7 days and 8 weeks to evaluate changes in AWE through histological and immunohistological analyses. Additionally, we evaluated AWE in patients who underwent imaging with a 3 T HR-MRI protocol. ASA exposure was defined as daily intake of 81 mg for at least six months prior to HR-MRI. AWE was quantified using three-dimensional AWE maps and histograms. Results Among rabbits exposed to ASA, the mean AWE was lower at 8 weeks compared to the controls (2.11 vs 2.15, p = 0.13). Immunostaining of the aneurysm wall in rabbits that received ASA revealed a reduced expression of CD68 + or cyclooxygenase-2 + cells, compared to the controls. A total of 99 patients with 120 UIAs were included in the HR-MRI analysis of UIAs. UIAs exposed to ASA (22/120) had significantly lower median AWE than those that were not exposed (0.60 vs 0.72, p = 0.032). Conclusion ASA therapy is associated with an objective reduction in AWE, suggesting a potential role in lowering the risk of aneurysm rupture.
Factors Associated With Stroke Recurrence After Initial Diagnosis of Cervical Artery Dissection

Stroke | March 27, 2025 | Volume: 56 | Issue: 6 | Pages: 1413-1421

10.1161/strokeaha.124.048215 | PMID 40143807

BACKGROUND: Patients presenting with cervical artery dissection (CAD) are at risk for subsequent ischemic events. We aimed to identify characteristics that are associated with increased risk of ischemic stroke after initial presentation of CAD and to evaluate the differential impact of anticoagulant versus antiplatelet therapy in these high-risk individuals. METHODS: This was a preplanned secondary analysis of the STOP-CAD study (Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection), a multicenter international retrospective observational study (63 sites from 16 countries in North America, South America, Europe, Asia, and Africa) that included patients with CAD predominantly between January 2015 and June 2022. The primary outcome was subsequent ischemic stroke by day 180 after diagnosis. Clinical and imaging variables were compared between those with versus without subsequent ischemic stroke. Significant factors associated with subsequent stroke risk were identified using stepwise Cox regression. Associations between subsequent ischemic stroke risk and antithrombotic therapy type (anticoagulation versus antiplatelets) among patients with identified risk factors were explored using adjusted Cox regression. RESULTS: In all, 4023 patients (mean age was 47.4 years; 44.5% were women) were included. By day 180, subsequent ischemic stroke occurred in 5.3% of the cohort. In adjusted Cox regression, factors associated with increased risk of subsequent ischemic stroke were prior history of ischemic stroke (adjusted hazard ratio [aHR], 7.31 [95% CI, 1.61–33.13]; P =0.010), presentation within 7 days from first symptoms (aHR, 3.04 [95% CI, 1.04–8.91]; P =0.043), infarct on baseline imaging (aHR, 9.85 [95% CI, 3.65–26.58]; P <0.001), and occlusive dissection (aHR, 2.34 [95% CI, 1.03–5.34]; P =0.043). Only patients with occlusive dissection demonstrated a reduced risk of subsequent ischemic stroke when treated with anticoagulation versus antiplatelets (aHR, 0.36 [95% CI, 0.16–0.80]; P =0.01). CONCLUSIONS: In this post hoc analysis of the STOP-CAD study, several factors associated with subsequent ischemic stroke were identified among patients with CAD. Furthermore, we identified a potential benefit of anticoagulation in patients with CAD with occlusive dissection. These findings require validation by meta-analyses of prior studies to formulate optimal treatment strategies for specific high-risk CAD subgroups.
The influence of prestroke disability on outcome in patients with a low Alberta Stroke Program Early CT Score who underwent endovascular thrombectomy

Journal of Neurosurgery | February 7, 2025 | Volume: 143 | Issue: 1 | Pages: 266-273

10.3171/2024.10.jns24888 | PMID 39919282

OBJECTIVE The definitive influence of prestroke disability on outcomes in patients with a low Alberta Stroke Program Early CT Score (ASPECTS) treated with endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO) remains unknown. This study aimed to investigate the impact of prestroke disability on outcomes in this specific population. METHODS Data from 32 international centers for AIS-LVO patients with a low ASPECTS who underwent EVT between January 2013 and December 2022 were analyzed retrospectively. Low ASPECTS and prestroke disability were defined as ASPECTS values of 2–5 and prestroke modified Rankin Scale (mRS) score ≥ 2. The primary outcome was a return to the prestroke mRS score at 90 days. Secondary outcomes were independent ambulation (mRS scores of 0–3) or a return to the prestroke mRS score at 90 days, good functional outcome (mRS scores of 0–2) or a return to the prestroke mRS score at 90 days, successful recanalization, and 90-day mortality. Safety outcomes were any intracranial hemorrhage or symptomatic intracranial hemorrhage. A symptomatic intracranial hemorrhage was defined as an intracranial hemorrhage with an associated worsening of ≥ 4 points in the National Institutes of Health Stroke Scale score. Outcomes were compared between patients with and without prestroke disability. RESULTS Of 293 patients, 50 (17.1%) had a prestroke disability. Of 50 patients, 20 (40.0%), 24 (48.0%), and 6 (12.0%) had prestroke mRS scores of 2, 3, and 4, respectively. The primary outcome showed no significant difference between the two groups. Compared with patients without prestroke disability, those with prestroke disability had a significantly smaller proportion of independent ambulation or return to prestroke mRS score (adjusted OR 0.13, 95% CI 0.03–0.53) and good functional outcome or return to prestroke mRS score (adjusted OR 0.21, 95% CI 0.05–0.91). Other secondary and safety outcomes showed no significant difference between the two groups. CONCLUSIONS The present study indicated that prestroke disability was not associated with a return to the prestroke mRS score at 90 days or intracranial hemorrhage. Physicians should not routinely exclude AIS-LVO patients with a low ASPECTS who have prestroke disability from EVT based on prestroke disability alone.
Abstract 153: The Effect of Aspirin on Aneurysm Wall Enhancement: A Study in Rabbits and Humans

Stroke: Vascular and Interventional Neurology | January 15, 2025 | Volume: 4 | Issue: S1 | Pages: No page available

10.1161/svin.04.suppl_1.153