Samaniego, Edgar A

Introduction Dural arteriovenous fistulas (dAVFs) have been associated with rapidly progressive dementia in relatively young patients. However, the specific angioarchitecture and characteristics of these dAVFs remain to be fully described. To better understand the specific characteristics of dAVFs associated with cognitive impairment (dAVF‐CI), we utilized the CONDOR multicenter database, which provides a large cohort of dAVF available. By analyzing data from patients with dAVFs‐ CI, we aimed to identify the key features distinguishing these cases and elaborate on the pathophysiology of dAVF‐CI. Methods CONDOR is an international multicenter database comprising 1077 (dAVFs) from 14 international centers. We conducted a retrospective analysis of the CONDOR database, focusing on patients diagnosed with dAVFs‐CI. Propensity score matching analysis was performed to compare Borden type II and type III dAVFs with and without cognitive impairment as control groups. Only dAVFs with cortical venous drainage were included as this aggressive subtype can present with non‐hemorrhagic neurologic deficits. Additionally, logistic regression was then employed to identify significant characteristics associated with dAVF‐CI. Results A total of 60 patients with dAVF‐CI and 60 control dAVFs were included in the analysis. The patients with dAVF‐CI had a mean age of 58 ± 18 years. It was found that all cases of dAVF‐CI exhibited venous hypertension. Additionally, there was a significant association between sinus stenosis and dAVF‐CI (OR: 2.85, 95% CI: 1.16‐7.55, p = 0.027). Moreover, dAVF‐CI cases were characterized by the presence of multiple arteriovenous shunts, with more arterial feeders (OR 1.56, 95% CI 1.22‐2.05, p <0.001) and draining veins (OR 2.05, 95% CI 1.05‐4.46, p = 0.004) compared to the control dAVFs. Venous ectasia was also found to be associated with dAVF‐CI (OR 2.38, 95% CI 1.13‐5.11, p= 0.024). Finally, some patients in which successful dAVF closure was achieved had symptom resolution during follow‐up (OR 2.86, 95% CI 0.85‐9.56, p = 0.09). Conclusion dAVFs‐CI tend to occur in relatively young patients and are characterized by the presence of venous hypertension. The development of sinus stenosis and venous ectasia further hinders proper drainage, contributing to the persistence of venous hypertension. Venous hypertension may impair critical structures such as the thalamus or the cortex leading to rapid cognitive impairment. Successful treatment of dAVFs‐CI can potentially reverse symptoms. Nonetheless, some dAVF‐CI may have persistent symptoms due to chronic hypertension and infarction.

OBJECTIVE Borden-Shucart type I dural arteriovenous fistulas (dAVFs) lack cortical venous drainage and occasionally necessitate intervention depending on patient symptoms. Conversion is the rare transformation of a low-grade dAVF to a higher grade. Factors associated with increased risk of dAVF conversion to a higher grade are poorly understood. The authors hypothesized that partial treatment of type I dAVFs is an independent risk factor for conversion. METHODS The multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research database was used to perform a retrospective analysis of all patients with type I dAVFs. RESULTS Three hundred fifty-eight (33.2%) of 1077 patients had type I dAVFs. Of those 358 patients, 206 received endovascular treatment and 131 were not treated. Two (2.2%) of 91 patients receiving partial endovascular treatment for a low-grade dAVF experienced conversion to a higher grade, 2 (1.5%) of 131 who were not treated experienced conversion, and none (0%) of 115 patients who received complete endovascular treatment experienced dAVF conversion. The majority of converted dAVFs localized to the transverse-sigmoid sinus and all received embolization as part of their treatment. CONCLUSIONS Partial treatment of type I dAVFs does not appear to be significantly associated with conversion to a higher grade.

Introduction: Despite comparable outcomes for different frontline techniques in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), there are sparse data regarding if and when to switch techniques if the first pass is unsuccessful. We aimed to investigate the impact of converting from one MT technique to another on the second MT attempt for AIS among patients with large vessel occlusion (LVO). Methods: This was a retrospective observational study using data from the large multicenter international Stroke Thrombectomy and Aneurysm Registry (STAR). Data from 29 stroke centers for 10,229 AIS patients treated with MT for LVO between January 2010 and December 2022 was investigated. The primary outcome measure was successful recanalization defined as modified Thrombolysis in Cerebral Ischemia (mTICI) score of 2b or higher. 90-day modified Rankin score (mRS) 0-2, mortality and symptomatic hemorrhage were used as secondary outcomes. Clinical and technical outcomes after the second MT attempt were compared between those with or without technique conversion. Results: Among 10,229 AIS patients, 1,797 AIS patients with LVO failed first pass recanalization and were included in this retrospective analysis. 927 patients were female (52%) and median (interquartile range) age was 72 (61-81) years. Converting to alternative techniques following a first failed attempt was more likely to be associated with successful recanalization at the second attempt (adjusted odds ratio 2.30, 95% CI: 1.37-3.86, P = 0.002) and 90-day good clinical outcome (adjusted odds ratio 2.10, 95% CI: 1.15-3.85, P = 0.02) after multivariate adjustment. Conclusions: This study demonstrates better clinical and technical outcomes with conversion of MT technique for the second attempt in AIS patients with LVO who failed first pass recanalization.

Introduction: The benefits of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients with unsuccessful mechanical thrombectomy (MT) are not well established. Methods: This study included patients from the Stroke Thrombectomy and Aneurysm Registry (STAR) who underwent MT for ICA, M1, or M2 occlusions with unsuccessful MT (mTICI score ≤ 2a). Patients who received IVT prior to MT were compared to those who received MT alone. Propensity score (PS) matching was performed using age, sex, premorbid modified Rankin Scale (mRS), admission National Institute of Health Stroke Scale (NIHSS), occluded vessel, ASPECTS score, mTICI score, and symptom onset to groin puncture time. The primary outcome was favorable 90-day outcomes (mRS 0-2). Results: Of 610 patients with unsuccessful MT, 219 were matched in each group. Median ages were 70 [IQR: 61 - 80] and 73 [IQR: 62 - 81] in the IVT + MT and MT alone groups, respectively. In the IVT + MT group. Final TICI scores of 0, 1, and 2a were achieved in 92 (42.0%), 33 (15.1%), and 94 (42.9%) patients, respectively, compared to 76 (34.7%), 29 (13.2%), and 114 (52.1%) in the MT alone group. The IVT + MT group showed a significantly. higher 90-day mRS of 0-2 (aOR: 2.54, 95% CI: 1.53-4.32) and mRS of 0-3 (aOR: 2.05, 95% CI: 1.36-3.12). There were no significant differences between the groups in intracranial hemorrhage (ICH), symptomatic ICH, or 90-day mortality rates. Conclusions: IVT is associated with improved functional outcomes in patients with unsuccessful MT. Ensuring that IVT is provided to all eligible stroke patients should remain a priority.

Introduction: Up to 50% of acute ischemic stroke (AIS) patients who undergo successful mechanical thrombectomy (MT) fail to achieve favorable outcomes (futile recanalization). In this study we aim to develop a machine learning (ML) model to predict futile recanalization (FR) in AIS patients who undergo MT. Methods: We used data from an ongoing large, multicenter database from 2013 to 2023. We included AIS patients treated with MT for ICA, M1, or M2 occlusion with successful recanalization (modified Thrombolysis in Cerebral Infarction [mTICI] score ≥ 2C) and procedure durations under 60 minutes. FR was defined as successful recanalization with 90-day modified Rankin Scale (mRS) 3-6. The dataset was divided into 75% for training and 25% for external validation. Using the Caret Package in R, multiple models were tested, and their performances were evaluated by the area under the curve (AUC) of receiver operating. Both baseline and pre-interventional characteristics were incorporated into the model. The selected model was then externally validated on a 25% validation dataset. Results: Among 2,546 qualified patients, FR occurred in 1,342 (52.7%). In univariate analysis, baseline characteristics were significantly different between FR and non-FR groups. The M5P model demonstrated the highest performance (AUC: 0.833; 95% CI: 0.7989-0.852; PPV: 0.8101) in comparison to other tested models such as logistic regression (AUC: 0.74), RF (AUC: 0.78), J48 (AUC: 0.78), SVM (AUC: 0.79), and GB (AUC: 0.79). The external validation of the model showed satisfactory results (AUC: 75.25; 95% CI: 70-80; PPV: 76.87). Conclusion: Utilizing clinical, pre-procedural, and imaging parameters, the M5P model can efficiently predict F) in AIS patients before attempting MT. This tool can assist neurointerventionalists in adequately choosing their MT candidates.

Introduction: Impact of race on outcomes in the treatment of intracranial aneurysm (IA) remains unclear. We aimed to investigate the relationship between race classified into White, Black, Hispanic, and other ("other" includes Native American or Alaska Native, Asian or Pacific Islander, and other race) and treatment outcomes in patients with ruptured and unruptured IAs. Methods: Stroke Thrombectomy and Aneurysm Registry (STAR) was a retrospective observational study. Data from 9 centers in the United States, Europe, and Asia for IA patients who undertook endovascular treatment (EVT) or microsurgical treatment (MST) between January 2016 and December 2020 were included for analysis. The primary outcome was 90-day mRS 0-2. Secondary outcomes included periprocedural cerebral infarction and intracranial hemorrhage, perioperative symptomatic cerebral vasospasm in ruptured IA and mortality, and all causes of mortality within 90 days. Results: 2,836 IA patients treated with EVT or MST were included. Among these 2,836 patients, 1,053 patients were White, 350 were Black, 264 were Hispanic, and 1,169 were other. The primary outcome in Hispanic patients was significantly lower than White patients (adjusted odds ratio [aOR] 0.36, 95% CI, 0.23-0.56, P < .001). The periprocedural cerebral infarction, perioperative mortality, and all causes of mortality in Hispanic patients were significantly higher than White patients (aOR 2.53, 95% CI, 1.40-4.58, P = .002, aOR 1.84, 95% CI, 1.00-3.38, P = .049, aOR 1.83, 95% CI, 1.06-3.17, P = .03, respectively). However, these outcomes were not significantly different in Black and other patients compared to White patients. Conclusions: This study demonstrates Hispanic IA patients are more likely to have a poor outcome at 90 days following EVT or MST than White patients.

Introduction: The first-pass effect (FPE), defined as a complete or near-complete recanalization after a single pass of a mechanical thrombectomy (MT) device, has been linked to favorable clinical outcomes. However, its effectiveness in acute ischemic stroke (AIS) patients with low ASPECTS (Alberta Stroke Program Early CT Score 2-5) has not been validated. Method: We utilized data from STAR, a multicenter database of 84 centers worldwide, to conduct a retrospective, cohort study on patients who underwent MT for internal carotid artery (ICA) or M1 occlusion presenting with ASPECTS 2-5. We compared the outcomes of patients who achieved FPE (successful recanalization with an mTICI score of 2c or higher in one pass) to those who did not. The primary outcome was a 90-day favorable outcome, defined as mRS 0-3. Secondary outcomes included any intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Results: Out of 10,229 patients in the STAR database, 250 patients met our inclusion criteria. Among those, 60 (24%) achieved FPE. There were no significant differences between the two groups in baseline, imaging, and procedural characteristics. FPE was significantly associated with higher odds of 90-day mRS 0-3 (adjusted odds ratio (aOR): 2.17, 95% confidence interval (CI): 1.04 - 4.20; P-value: 0.04) and lower rates of ICH (OR: 0.49, 95% CI: 0.25 - 0.93, P-value: 0.03). However, there was no significant difference in sICH rates (OR: 0.84, 95% CI: 0.31 - 2.04, P-value: 0.70). Conclusion: Achieving FPE in AIS stroke patients with low ASPECTS was associated with significantly higher rates of good functional outcomes and lower rates of ICH.

Introduction: Real-world data showed that less than half of the acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) presenting with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (2-5) achieved favorable outcomes at 90 days after mechanical thrombectomy (MT). In this study, we aim to investigate the relationship between the number of MT passes at which successful recanalization is obtained and outcomes in LVO-related AIS patients with low ASPECTS. Methods: This retrospective cohort study was performed on the data from 31 thrombectomy-capable centers between 2013 to 2022. Successful recanalization was defined as modified Thrombolysis in Cerebral Ischemia Score≥ 2b. The primary outcome was a 90-day modified Rankin Scale (mRS) of 0-3. Secondary outcomes were symptomatic intracranial hemorrhage and intracranial hemorrhage within 24 hours and mortality at 90 days. Outcomes were compared among patients with unsuccessful recanalization, and successful recanalization at first, second, third, and more than four passes. Results: A total of 297 patients with a median age of 70 [IQR 59-78] years were included and 140 (47.1%) were female. In 239 (80.4%) patients, successful recanalization was achieved: 88 patients (29.6 %) with 1 pass, 59 patients (19.9 %) with 2 passes, 35 patients(11.8%) with 3 passes, and 57 patients (19.2%) with more than 4 passes. Compared to unsuccessful recanalization, successful recanalization at first pass (adjusted OR 5.25, 95% CI 1.78 - 17.1), second passes (adjusted OR 5.20, 95% CI 1.68 - 17.6), and passes 4 (adjusted OR 4.90, 95% CI 1.68 - 17.6) was related to 90-day mRS 0-3. Recanalization status and MT attempt number were not related to secondary outcomes except for 90-day mortality. Compared to unsuccessful recanalization, successful recanalization at second and third passes were inversely related to 90-day mortality (adjusted OR 0.37, 95% CI 0.14 - 0.93; adjusted OR 0.33, 95% CI 0.11 - 0.95, respectively). Conclusion: The present results indicated that successful recanalization was related to 90-day good outcome regardless of the number of MT passes but the odds of achieving favorable outcome declines with each pass.

Introduction: The combination of intravenous or intra-arterial thrombolysis with mechanical thrombectomy (MT) for acute ischemic stroke (AIS) has been thoroughly investigated. However, no study has explored the outcomes of combining both intravenous and intra-arterial thrombolysis with MT. Methods: Data from Stroke Thrombectomy and Aneurysm Registry (STAR) from 2013 to 2023 was utilized. We compared AIS patients with LVO who underwent MT with combined intra-venous and intra-arterial thrombolysis (IV+IA) and with intra-venous thrombolysis alone (IV). We performed propensity score (PS) matching between the two groups using age, sex, premorbid mRS, admission NIHSS, occluded vessel, ASPECTS score, time from symptoms onset to arterial puncture, and frontline technique. Primary outcomes were any intracranial hemorrhage (ICH) and symptomatic ICH (sICH). Secondary outcomes included successful recanalization (mTICI ≥2C), early neurological improvement (defined as 4 or more points improvement in NIHSS score in 24 hours), 90-day modified Rankin Scale (mRS) 0-2, mRS 0-1, and mortality. Results: A total of 2495 LVO-related AIS patients were included, consisting of the IA+IV group (n = 266) and the IV group (n = 2228). Propensity matching yielded 192 well-matched patients in each group. No significant differences were observed between the groups in either ICH or sICH (odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.61-1.52, p = 0.60; OR: 0.92, 95% CI: 0.42-2.03, p > 0.90, respectively). The IA+IV group had a significantly lower proportion of successful recanalization (OR: 0.41, 95% CI: 0.27-0.62, p < 0.001), and early neurological improvement (OR: 0.55, 95% CI: 0.30-1.00). However, 90-day mRS 0-2, mRS 0-1, and mortality rates showed no significant differences between the two groups. Conclusion: The findings of this study suggest that the combined use of IA and IV thrombolysis in AIS patients undergoing MT is safe. Although the IA+IV group demonstrated lower rates of recanalization and early neurological improvement, long-term functional outcomes and mortality rates were comparable to the IV-thrombolysis group, indicating a potential delayed benefit of additional IA thrombolysis therapy.

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: