Intracranial Stenting Research Articles

Fabrication of the locally reinforced open-cell nitinol stents for intracranial vascular aneurysm

ABSTRACT Intracranial vascular stent-assisted coil embolization has been widely used for intracranial vascular aneurysm. However, there are serious complication risks, such as thromboembolism, stent migration and spring coil prolapse, due to the inappropriate radial force, poor wall apposition and oversized mesh. Therefore, a locally-reinforced intracranial vascular stent was designed to improve the radial force and wall apposition performance. Based on finite element analysis and substantial measurements, the local radial force has improved 38.9% and thestability of the coil embolism has been enhanced as well. The releasing test in vitro suggests the stent can adhere to the vascular wall very well without the ‘Gator backing’ phenomenon. Furthermore, the implanting test in vivo shows complete endothelialization without restenosis and hyperplasia in 4 weeks. The outcomes of this study provide optimal design of the locally reinforced nitinol stent used for intracranial aneurysm therapy with reduced risks of vascular embolism and haemorrhagic apoplexy after implantation.

Eptifibatide, an Older Therapeutic Peptide with New Indications: From Clinical Pharmacology to Everyday Clinical Practice

Therapeutic peptides are oligomers or short polymers of amino acids used for various medical purposes. Peptide-based treatments have evolved considerably due to new technologies, stimulating new research interests. They have been shown to be beneficial in a variety of therapeutic applications, notably in the treatment of cardiovascular disorders such as acute coronary syndrome (ACS). ACS is characterized by coronary artery wall damage and consequent formation of an intraluminal thrombus obstructing one or more coronary arteries, leading to unstable angina, non-ST elevated myocardial infarction, and ST-elevated myocardial infarction. One of the promising peptide drugs in the treatment of these pathologies is eptifibatide, a synthetic heptapeptide derived from rattlesnake venom. Eptifibatide is a glycoprotein IIb/IIIa inhibitor that blocks different pathways in platelet activation and aggregation. In this narrative review, we summarized the current evidence on the mechanism of action, clinical pharmacology, and applications of eptifibatide in cardiology. Additionally, we illustrated its possible broader usage with new indications, including ischemic stroke, carotid stenting, intracranial aneurysm stenting, and septic shock. Further research is, however, required to fully evaluate the role of eptifibatide in these pathologies, independently and in comparison to other medications.

Abstract Number ‐ 154: Outcomes of Rescue Intracranial Stenting vs Failed Recanalization during Mechanical Thrombectomy

Introduction Rescue stenting may be considered during mechanical thrombectomy (MT) if a newly recanalized intracranial vessel keeps re‐occluding, or recanalization is not achieved with conventional thrombectomy methods. There are multiple published case series with mixed results on safety and efficacy of this approach, and there are no available randomized trials. We aimed to compare the outcomes of rescue intracranial stenting with unsuccessful/poor reperfusion after MT. Methods Retrospective review of ischemic stroke patients who underwent MT from 2016–2021. Emergent intracranial stent patients were selected and compared with those who had poor/unsuccessful post‐procedural reperfusion (TICI 0–2a). Initial ASPECT score, NIHSS, number of passes, and MT method (aspiration vs stentriever) were recorded. Complications (intracranial hemorrhage, vessel perforation, groin or retroperitoneal hematoma, or distal embolization), final infarct size, 90‐day mRS, and mortality were analyzed. Results Sixteen patients underwent emergent intracranial stenting. Of the 89patients with failed MT, 34 had TICI 2a, 11 had TICI 1, and 44 had TICI 0 reperfusion. All 16 stenting patients achieved TICI 2B‐3 grade recanalization. Pre‐procedure ASPECT score was similar between both groups. Six patients had either intracranial vertebral or basilar artery stenting, and 10 had either intracranial ICA or MCA stenting. Patients with posterior compared to anterior circulation involvement were more likely to receive stenting (50% vs 11%, p = 0.003). There were no differences in the stenting versus non‐stenting group in 24‐hour post intervention NIHSS, post‐procedural complications, intracranial hemorrhage, infarct size, and mortality (75% vs 67%). The stenting group had better functional independence (mRS 0–2) at 90 days (33% vs 11%, p = 0.04). There were no outcome differences in anterior compared to posterior circulation stenting. Conclusions Rescue stenting was more often seen with posterior circulation strokes. In patients with failed or unsuccessful reperfusion after conventional MT, emergent stenting achieved better 90‐day functional independence without increasing rates of complications, intracranial hemorrhage, or mortality.

Impact of cerebral small vessel disease on symptomatic in-stent restenosis in intracranial atherosclerosis.

Cerebral small vessel disease (CSVD) commonly coexists with intracranial atherosclerotic stenosis (ICAS). In-stent restenosis (ISR) affects the nonprocedural outcome of severe symptomatic ICAS after intracranial stenting. However, only 8%-27% of ISR patients are symptomatic, which highlights the importance of the investigation of risk factors associated with symptomatic ISR (SISR) to improve long-term functional outcome. Whether CSVD is associated with SISR remains unclear. The authors tested the hypothesis that CSVD is associated with SISR in ICAS patients after intracranial stenting. This retrospective study enrolled 97 patients who were symptomatic due to severe anterior circulation ICAS treated with intracranial stenting. SISR was evaluated with clinical and vascular imaging follow-up. CSVD subtypes, including white matter hyperintensities (WMHs), enlarged perivascular spaces, and chronic lacunar infarctions, were evaluated. Cox regression analysis was used to compare the incidence of SISR between patients with and without CSVD. Of the enrolled patients, 58.8% had CSVD. The 1- and 2-year ISR rates were 24.7% and 37.1%, respectively. Of the CSVD subtypes, SISR was associated with deep WMHs (DWMHs; HR 5.39, 95% CI 1.02-28.44). DWMH Fazekas scale grades 2 (HR 85.54, 95% CI 2.42-3018.93) and 3 (HR 66.24, 95% CI 1.87-2352.32) were associated with SISR, but DWMH Fazekas grades 0 and 1 were not. The proportions of SISR in patients with DWMH Fazekas grades 0, 1, 2, and 3 were 16.7%, 33.3%, 50%, and 100%, respectively. Patients with CSVD have a higher risk of SISR than those without CSVD. Of the CSVD subtypes, patients with DWMHs are associated with SISR. The DWMH Fazekas scale score is considered to be a predictor for SISR.

Abstract Number ‐ 187: Short‐term Clinical Outcomes Amongst Patients On Anticoagulation and DAPT Who Underwent Stenting and Mechanical Thrombectomy

Introduction Dual antiplatelet therapy has long been established as the preferred treatment option for patients with intracranial or extracranial stenting. Anticoagulation is the preferred treatment option for patients at high risk of stroke with embolic risk factors. There is no data currently available analyzing patients presenting with acute ischemic stroke on anticoagulation who require an intracranial and or extracranial stent (IC/EC), requiring DAPT and anticoagulation with mechanical thrombectomy. Our objective is toinvestigate differences in recanalization and outcomes as well as safety of DAPT and AC in the setting of AIS post MT with stenting when compared to patients without AC. Methods A retrospective search at a large comprehensive stroke center was conducted and data was analyzed from 2013 to 2022. Patients presenting with AIS on AC who had MT and required IC/EC stent were selected and compared to patients not on AC. Outcomes were measured as symptomatic ICH and mortality. Patient demographics, stroke risk factors and stroke severity were abstracted amongst other variables. Results There were 301 patients out of 917 (42.9% Female) who presented with anticoagulation use prior to mechanical thrombectomy requiring ic/ec stent placement and DAPT therapy. See Table 1 for baseline demographics. Symptomatic ICH was seen in 24 (7.9%) compared to 50 (8.1%), Odds ratio 0.86/ p‐value = 0.573, Mortality was seen in 51 (16.9%) patients who received DAPT and a/c compared to 129 (20.9%) (OR 0.67) p = 0.028. Logistic regression model did not show any significant difference (See Table 2). Conclusions There was no statistical difference in symptomatic ICH in acute ischemic stroke patients treated with mechanical thrombectomy and acute stenting on anticoagulation when compared to those without anticoagulation. There was statistical difference in mortality and DAPT/AC actually had lower mortality rates. This data suggests that performing intracranial and extracranial stenting in the acute stroke setting while on anticoagulation and adding DAPT is safe. A larger multicenter study with longer follow up is needed to further confirm these findings.

Abstract Number ‐ 132: Stent‐assisted repair of the intracranial aneurysms with loading dose of antiplanets and perioperative events.

Introduction Introduction: Thromboemboembolic event (TEE) remains the mail perioperative challenge in addition to the potential intracranial hemorrhage (IH) in stent‐assisted repair of intracranial aneurysms (IA), and there are no standard antiplatelet strategies. Bases on the data, antiplatelets effects are more pronounce in first 4 hours after administration of antiplatelets. Objectives: To evaluate the effect of acute loading doses of aspirin and clopidogrel (LDAC) in TEE and hemorrhagic events associate with stent‐assisted repair of intracranial aneurysm. Additionally, to review the outcome of those patient who underwent stent‐assisted coiling using LDAC. Methods Consecutive patients underwent stent‐assisted repair of aneurysm using loading doses of aspirin 324 mg (4 baby aspirin) and clopidogrel 300 mg 2 to 4 hours before the procedure were enrolled from 2011 to 2022. Patients demographics including intra‐operative and post operative events were recorded. Outcome was measured using modified Rankin Scale (mRS) score. Results 96 patients (6 had baseline mRS 2) with mean age of 53 ± 13 underwent 98 stent‐assisted procedures including two Y‐stent neck reconstructions to treat 98 (6 ruptured and 41 symptomatic aneurysms) IA. Aneurysms are Right internal carotid artery (ICA) 25, left ICA 30, middle cerebral artery (MCA) 22, basilar artery 17 and anterior communicating artery 2.Stent deployment was achieved in all cases. Coil prolapsed and stretching occurred in one right ICA case, required deployment of additional 3 intracranial stents and one carotid artery stent with no clinical events. There was no intra‐operative rupture or IH. A small perioperative left hemispheric subarachnoid hemorrhage was observed on a right MCA aneurysm on day 3 after discharged, which resolved spontaneously without stopping antiplatelet. Intra‐operative stent thrombosis developed in one who had two aneurysms in right ICA with significant cerebrovascular risk factors; resolved with intraarterial integrilin followed by intravenous for infusion with no clinical consequences immediately and 12 months follow‐up; was resistant to clopidrogel and placed on ticagrelor.Post‐operative TEE were observed in 2 cases (2%); first event was observed on day 2 in a 42 years old woman with a giant right ICA giant aneurysm with NIHSS 6 and who recovered completely (NIHSS 0, mRS 1) in 90 days. The second event was visual distortion and diplopia (NIHSS 0) developed on day 2 in a 66 years old woman with basilar artery aneurysm. Her symptoms resolved completely and return to nursing job. All ruptured and symptomatic aneurysms were secure immediately and there are no subarachnoid hemorrhages during follow‐up. TEE was associated withperiorerative smoking. Immediate complete and near complete obliteration of aneurysm was observed in 66% and subtotal in 34%. There was no mortality or permanent disability in our series. 90 days mRankins 0 and 1 was observed in 96% and mRS 2 in 7% (baseline mRS) Conclusions Our study revealed that LDAC in stent‐assisted repair of IA is associated with a low TEE without added risk of IH with clinical good outcome. Our antiplatelets loading regimen may be an option in stent‐assisted repair of IA, especially when patients are unreliable and aneurysms are symptomatic. Further studies are required.

Therapeutic strategies for acute basilar-artery occlusion

Therapeutic strategies for acute basilar-artery occlusion

Abstract Number ‐ 145: Impact of Landmark Trials on Intracranial Stenting Utilization for Intracranial Atherosclerotic Disease in the US

Introduction The Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) trial published in 2010 showed aggressive medical therapy is superior to percutaneous transluminal angioplasty and stenting (PTAS) for intracranial atherosclerotic disease (ICAD). Following the pivotal positive mechanical thrombectomy (MT) trials in 2015, MT utilization in the United States (US) has increased. Rescue ICAD stenting may be needed in MT patients with underlying ICAD but it remains uncertain whether PTAS use for ICAD has changed over this time. The aim of this study is to describe national trends in the utilization of PTAS for ICAD in the US before and after SAMMPRIS and following the pivotal MT trials. Methods We used a constellation of International Classification of Diseases ninth and tenth revision diagnostic/procedural codes to identify all elective and non‐elective adult (> = 18 years) ICAD admissions with or without infarction containing concomitant codes for PTAS in the 2007–2019 National Inpatient Sample. Admissions containing codes for subarachnoid hemorrhage, unruptured intracranial aneurysms or benign intracranial hypertension were excluded. We combined weighted counts of PTAS admissions with annual US adult census data to obtain prevalence of PTAS. We used joinpoint regression to evaluate trends in PTAS use over time. Results Across the study period, there were 16,477 weighted admissions for ICAD undergoing PTAS in the US. 52.4% of these admissions were in patients 60–79years and 43.2% were in women. 74.3% of these admissions were non‐elective and this proportion increased over time (P = 0.019). 26.5% of all admissions had concurrent codes for MT but this proportion increased by almost ten‐fold over time from 4.3% in 2007 to 40.0% in 2019. On join point regression, PTAS utilization increased but insignificantly from 3.0/million population in 2007 to 5.7/million population in 2010 (Annualized percentage change, APC 11.2%, 95%CI ‐11.8 to 40.3, p = 0.290), declined also insignificantly from 2010–2013 (APC ‐13.2, 95%CI ‐48.4 to 45.8, p = 0.514) and increased significantly from 3.55/million in 2013 to 3.80/million in 2014 and exponentially across the rest of the period to 8.4 cases/million in 2019 (APC 15.4, 95%CI 9.2 to 22.0, p = 0.001). Upon stratification by admission type, most of the increase across the period 2013/2014 to 2019 occurred in non‐elective admissions (Figure 1). Utilization in elective admissions varied from 0.92 to 1.96 cases per million population but this did not change significantly across the study period. Conclusions PTAS utilization for ICAD declined in the US after SAMMPRIS but has increased following publication of pivotal MT trials mainly in non‐elective admissions. PTAS utilization increased significantly following publication of pivotal MT trials likely in ICAD patients who required rescue stenting.. Additional prospective studies are needed to determine the long‐term outcomes of concurrent PTAS and MT as this is not a group of patients that was studied in SAMMPRIS.

Comparison of three antithrombotic strategies for emergent carotid stenting during stroke thrombectomy: a multicenter study

BackgroundPeriprocedural antithrombotic treatment is a key determinant for the risk–benefit balance of emergent carotid artery stenting (eCAS) during stroke thrombectomy. We aimed to assess the safety and efficacy of three...

Abstract TP137: Rescue Angioplasty And/or Stenting For Acute Large Artery Occlusion Of Posterior Circulation With Underlying Intracranial Atherosclerosis

Background: Prior studies have shown rescue intracranial angioplasty and/or stenting (PTAS) is safe and efficacious in acute large vessel occlusion (LVO) of the anterior circulation with underlying intracranial atherosclerotic disease (ICAD). We investigated the safety and efficacy of acute intracranial angioplasty and/or stenting in patients with posterior circulation intracranial atherosclerosis-related occlusion (ICAS-O). Methods: Through the utilization of a prospectively collected endovascular database at a comprehensive stroke center between January 2016- May 2022, variables such as demographics, co-morbid conditions, symptomatic intracerebral hemorrhage (ICH), the mortality rate at discharge, and recanalization rate and favorable clinical outcome, modified thrombolysis in cerebral infarction score (mTICI) and favorable clinical outcome (modified Rankin Scale (mRS), were examined. The outcomes between acute PTAS + MT in the anterior and posterior circulation were compared. Results: There were a total of 75 acute ischemic stroke (AIS) patients who underwent rescue PTAS, of which 15 (20.0 %) were posterior circulation ICAS-O group. Baseline characteristics were similar between the groups except for gender (6.7 % vs 45.0) and atrial fibrillation (21.7% vs 0.0%). There was no statistical difference in discharge NIH Stroke Scale (mean, 18 vs 23%, P = 0.860) or favorable outcome (modified Rankin Scale ≤ 2) at 90 days (46.7% vs 38.7 %, P = 0.477) between the posterior and anterior ICAS-O groups respectively. Symptomatic ICH rate tended to be higher in the anterior group (11.7 vs 6.7%, P = 0.495). Conclusions: Rescue angioplasty and/or stenting seem safe treatment options for posterior circulation ICAS-related LVO. Further larger multicenter prospective studies are required to corroborate the results of our study.

Predictors of hyperperfusion syndrome after stent implantation in symptomatic intracranial atherosclerotic stenosis.

Hyperperfusion syndrome (HPS) is a serious complication after stent implantation in symptomatic intracranial atherosclerotic stenosis (ICAS). This study aims to explore the predictive value of preprocedural computed tomography perfusion (CTP) for HPS after intracranial stenting. In this retrospective case-control study we collected data from consecutive patients from June 2012 to September 2019 who underwent stent implantation due to severe symptomatic ICAS. Patients who underwent CTP before the procedure were enrolled. CTP was postprocessed using the automated RAPID software to assess the preoperative cerebral perfusion. According to the presence or absence of HPS, the patients were classified into two groups: the HPS group and the non-HPS group. The baseline data, lesion characteristics, and preoperative CTP parameters between the two groups were compared. The receiver operating characteristic (ROC) curve analysis was performed to determine the optimal predictor of HPS. Among the 170 eligible patients, 6 patients (3.53%) had HPS, including 3 who presented with intracranial hemorrhages (ICHs), 1 who had dysphoria, 1 who had delirium, and 1 who had a headache. There were no significant differences in baseline and lesion characteristics between the HPS and non-HPS groups. Compared with the non-HPS group, the HPS group had a significantly higher volume of time-to-maximum (Tmax) >4 s (429.5 vs. 93 mL; P=0.006) and Tmax >6 s (200 vs. 0 mL; P=0.003). The optimal volume threshold for maximizing sensitivity in predicting HPS was 65.5 mL with Tmax >4 s [area under the curve (AUC), 0.832; 95% confidence interval (CI): 0.650 to 1.000; P=0.006]. Tmax >4 s volume may be a predictor of HPS after stent implantation in symptomatic ICAS. Further prospective studies should be conducted to confirm our conclusion.

Abstract WP97: Routine MRI Reveals Prior Stroke In The Same Vascular Territory In Half Of Patients Presenting With Acute Ischemic Stroke Due To Intracranial Atherosclerotic Disease

Introduction: In 2012, after SAMMPRIS demonstrated worse 30-day outcomes with Wingspan intracranial stent placement for intracranial atherosclerotic disease (ICAD), the FDA narrowed the “on-label” indication to a very specific subset of patients with symptomatic ICAD. The updated criteria require a prior stroke in the territory of the symptomatic vessel based on clinical history. Limitations in the accuracy of diagnosis of clinical stroke may be overcome with the use of MRI to identify any prior stroke - whether clinical or subclinical - which could expand the number of patients who are eligible for stenting. Methods: This was a retrospective analysis of consecutive cases of acute ischemic stroke attributable to ICAD with 50-99% stenosis in the symptomatic vessel from July 2019 - June 2022. MRI FLAIR sequences were reviewed for imaging evidence of prior infarction in the vascular territory of the symptomatic vessel. Subgroup analysis was performed based on stroke location, infarct pattern, degree of stenosis, and premorbid medication use. Results: 73 patients met inclusion criteria. Mean age was 72, and 41% were women. 37 patients (51%) exhibited MRI evidence of prior stroke in the same vascular territory. Of these, only 18/37 (49%) reported a prior clinical stroke. The frequency of prior stroke on MRI was similar with anterior (51%) and posterior (50%) circulation ICAD. Frequency of prior stroke based on infarct pattern was 64% for border zone infarction, 42% for thromboembolism, and 55% for branch atheromatous disease. Of the 31 patients who had degree of stenosis quantified on DSA, the frequency of prior infarction was 63% in patients with 70-99% stenosis versus 48% in those with <70% stenosis. Only 1 patient (1.4%) met FDA on-label criteria for intracranial stenting. The most common reason for ineligibility was absent history of clinical stroke in the territory of the symptomatic vessel (75%). Conclusions: In patients presenting with acute stroke due to symptomatic ICAD, half exhibit MRI evidence of a prior stroke in the symptomatic arterial territory, and half of these prior strokes are not reported from clinical history. Routine MRI can be a valuable tool to identify prior stroke in the symptomatic territory, which may in turn expand therapeutic options for ICAD.

Intracranial Artery Calcifications Profile as a Predictor of Recanalization Failure in Endovascular Stroke Treatment.

Acute ischemic stroke with large or medium-vessel occlusion associated with intracranial artery calcification (IAC) is an infrequent phenomenon presumably associated with intracranial atherosclerotic disease. We aimed to characterize IAC and its impact on endovascular treatment outcomes. We performed a retrospective cross-sectional study of consecutive patients with stroke treated with thrombectomy from January 2020 to July 2021 in our institution. We described IAC findings (length, density, and location pattern) on baseline noncontrast computed tomography. Patients were divided into 3 groups: IAC related to the occlusion location (symptomatic-IAC group), unrelated to the occlusion (asymptomatic-IAC group), and absence of any IAC (non-IAC group). We analyzed the association between the IAC profile and outcomes using logistic regression models. Intracranial angioplasty and stenting were considered rescue treatments. Of the 393 patients included, 26 (6.6%) patients presented a symptomatic-IAC, 77 (19.6%) patients an asymptomatic-IAC, and in 290 (73.8%) patients no IAC was observed. The rate of failed recanalization (expanded Thrombolysis in Cerebral Infarction 0-2a) before rescue treatment was higher in symptomatic-IAC (65.4%) than in asymptomatic-IAC (15.6%; P<0.001) or non-IAC (13.4%; P<0.001). Rescue procedures were more frequently performed in symptomatic-IAC (26.9%) than in asymptomatic-IAC (1.3%; P<0.001) and non-IAC (4.1%; P<0.001). After adjusting for identifiable clinical and radiological confounders, symptomatic-IAC emerged as an independent predictor of failed recanalization (odds ratio, 11.89 [95% CI, 3.94-35.91]; P<0.001), adoption of rescue procedures (odds ratio, 12.38 [95% CI, 2.22-69.09]; P=0.004), and poor functional outcome (90-day modified Rankin Scale score ≥3; odds ratio, 3.51 [95% CI, 1.02-12.00]; P=0.046). The presence of IAC related to the occlusion location is associated with worse angiographic and functional outcomes. Therefore, identification of symptomatic-IAC on baseline imaging may guide optimal endovascular treatment strategy, predicting the need for intracranial stenting and angioplasty.

Abstract 138: Hypoperfusion Delay Volume Predicts Early Stroke Recurrence Risk In Symptomatic Anterior Circulation Intracranial Atherosclerotic Disease

Introduction: Data on predictors of early stroke recurrence in patients with symptomatic intracranial atherosclerotic disease (sICAD) is limited. We hypothesized that hypoperfusion delay predicts stroke recurrence within 90-days. Methods: We retrospectively collected all patients hospitalized with anterior circulation sICAD over 3 years (April 2019-April 2022) at a comprehensive stroke center. We collected demographics, clinical risk factors, radiological variables, and treatment strategies. Patients with an indication for anticoagulation such as atrial fibrillation and those with intracranial stenting or angioplasty were excluded. The outcome (verified by two independent reviewers) was recurrent stroke within 90 days in the affected artery. We assessed factors associated with stroke recurrence. We measured the effect of hypoperfusion delay volume on stroke recurrence using Cox-regression models. Results: Out of 131 sICAD hospitalizations during the study period, 66 involved the middle cerebral artery (MCA) M1 segment or intracranial internal carotid artery (ICA) and 44 patients met the inclusion criteria. The mean age was 71 years and 41% were women; 75% were treated with best medical management (dual antiplatelet therapy/high intensity statin therapy); and 75% had baseline perfusion imaging performed. Over 90 days, 11/44 (25%) patients had recurrent stroke. Factors associated with recurrence stroke were no best medical management (15.2% vs. 54.5%, p = 0.02), hypoperfusion Tmax&gt;4 sec mismatch volume (p = 0.003), and hypoperfusion delay Tmax&gt;6 sec mismatch volume (p=0.01). Using Youden’s cutoff for Tmax&gt;4 sec mismatch (13 mL) and for Tmax&gt;6 sec mismatch (5 mL), the risk of recurrent stroke at 90 days in separate models was higher in patients with Tmax&gt;4 sec delay mismatch volume &gt; 13 mL (HR 11.98 95% CI 1.48-96.96 p=0.02) and Tmax&gt;6 sec mismatch volume &gt; 5 mL (HR 4.37 95% CI 1.02-18.82, p=0.048). Effect size of the associations did not meaningfully change after adjusting for best medical management. Conclusion: Hypoperfusion delay is associated with an increased recurrent stroke risk within 90 days in patients with sICAD, despite best medical management. Validation by large prospective studies is warranted.

Abstract TP151: Predictors Of Mechanical Thrombectomy Failure

Background: Mechanical thrombectomy is standard of care for acute ischemic stroke secondary to LVO however MT failure (MTF) occurs in approximately 15% of cases. Objective: Investigate patient and procedural characteristics that predict MTF. Methods: Retrospective review of prospectively collected, Stroke Thrombectomy and Aneurysm Registry. Patients who underwent MT for LVO were included and categorized by MT Success (MTS) or MTF, defined as mTICI≥2b or &lt;mTICI2b, respectively. Demographics, pretreatment, and treatment information were included in UVA and MVA for prediction of MTF. Results: A total of 8452 patients were analyzed, and 1301(15.4%) experienced MTF.MTF patients were older(73 vs.71, p=0.008)had higher poor premorbid mRS(10.8% vs 8.4%, p=0.17).Onset to puncture was greater in MTF group(442 vs.411 min, p=0.006).There were more ICA occlusions(15.6% vs. 13.5%)and basilar occlusions(7.8% vs.6.2%)in the MTF group and more M1 occlusions(42.2%vs.37.5%)in the MTS group (p&lt;0.001).More patients underwent aspiration as the final technique in the MTS group(35.3% vs 32.9%).Number of passes(3 vs 2)and procedure time (77.3 vs 46.1 min) were higher in the MTF group (p&lt;0.001). More patients in the MTF group required IA thrombolytic(14.7% vs. 8.3%, p&lt;0.001).More patients in the MTS group had rescue stenting(7.9% vs 4.8%).There were more complications (14.7% vs 6.2%) and more symptomatic ICH(9.9% vs 5.7%, p&lt;0.001)in the MTF group. Favorable outcome at 90 days was greater in the MTS group(42.6% vs 18.3%, P&lt;0.001).On UVA, age, poor pretreatment mRS, posterior circulation occlusion, final technique SR, increased number of passes, increased procedure time were associated with increased odds of MTF, while M1-M2 occlusions and rescue intracranial stenting with decreased odds of MTF. These correlations remained significant on MVA for final technique SR, rescue intracranial stenting, number of passes, and procedure time. Conclusion: MTF is associated with more complications and worse outcome. Final use of aspiration and rescue intracranial stenting may increase chances of recanalization.

Abstract 95: High Proportion Of Granulocytes Form Intracranial Thrombus Is Associated With Increased Stiffness And Resistance To Endovascular Recanalization

Hypothesis: We aim to identify a profile of intracranial thrombus resistant to recanalization by standard mechanical thrombectomy (MT) in acute stroke treatment. Methods: First extracted clot of each MT were analyzed by Flow Cytometry obtaining composition of main leukocyte populations: granulocytes, monocytes and lymphocytes. Demographics, reperfusion treatment and grade of recanalization were registered. MT Failure ( MTF) was defined as final Thrombolysis in Cerebral Infarction score IIa or lower and/ or need of permanent intracranial stenting as a rescue therapy after standard MT. In other cohort of cases, unconfined compression tests were performed to explore stiffness of retrieved clots . We looked for correlation between mechanical characterization tests and clot composition. Results: Among 225 patients, there were 13 % of MTF that were significantly associated to atherosclerosis etiology ( 33.3% vs. 15.9% ; p 0.021) , more passes ( 3 vs. 2; p &lt;0.001), higher proportion of clot granulocytes ( 82.46% vs. 68.90% ; p &lt;0.001) and lower proportion of clot monocytes ( 9.18% vs.17.34% ; p&lt;0.001). The proportion of clot granulocytes (aOR 1.07; 95% CI 1.01-1.14) remained as an independent marker of MTF. Among Thirty eight clots tested by unconfined compression median clot stiffness was 30.2 (IQR, 18.9-42.7) kPa. There was a positive correlation between granulocyte proportion and thrombi stiffness (Pearson’s r=0.35, p=0.032). Conclusions: There is a positive correlation between granulocyte proportion and thrombi stiffness that may explain endovascular resistance to recanalization. Influence of granulocytes within thrombus may be a target for future reperfusion treatments.

Comparison of Gelatin/Polylysine- and Silk Fibroin/SDF-1α-Coated Mesenchymal Stem Cell-Seeded Intracranial Stents.

Endothelialization of the aneurysmal neck is essential for aneurysm healing after endovascular treatment. Mesenchymal stem cell (MSC)-seeded stents can promote aneurysm repair. The biological effects of coated and uncoated nitinol intracranial stents seeded with MSCs on vascular cells and macrophage proliferation and inflammation are investigated. Two stent coatings that exert pro-aggregation effects on MSCs via different mechanisms are examined: gelatin/polylysine (G/PLL), which enhances cell adhesion, and silk fibroin/SDF-1α (SF/SDF-1α), which enhances chemotaxis. The aim is to explore the feasibility of MSC-seeded coated stents in the treatment of intracranial aneurysms. The G/PLL coating provides the highest cytocompatibility and blood compatibility substrate for MSCs and vascular cells and promotes cell adhesion and proliferation. Moreover, it enhances MSC secretion and regulation of vascular cell and macrophage proliferation and chemotaxis. Although the SF/SDF-1α coating promotes MSC secretion and vascular cell chemotaxis, it induces a greater degree of macrophage proliferation, chemotaxis, and secretion of pro-inflammatory factors. MSC-seeded stents coated with G/PLL may benefit stent surface endothelialization and reduce the inflammatory response after endovascular treatment of intracranial aneurysm. These effects may improve aneurysm healing and increase the cure rate.

Intracranial venous stenting for idiopathic intracranial hypertension.

There is increasing evidence in the literature to support venous sinus stenting in patients with idiopathic intracranial hypertension who fail first-line therapy. Venous sinus stenting is a safe and successful technique compared with cerebrospinal fluid diversion procedures. This study examines the clinical outcomes of patients post intracranial venous stenting for intracranial hypertension across three tertiary hospitals in Western Australia. A retrospective analysis was performed on 83 consecutive patients treated with intracranial venous stenting for IIH at three tertiary hospitals from October 2013 to March 2020. Data were collected from outpatient clinic letters, electronic discharge letters, electronic radiological imaging and procedural reports. 89.2% patients were able to cease Acetazolomide post stenting. 78.3% patients reported resolution of headaches. 84.3% patients demonstrated resolution of their papilloedema. 91.6% patients demonstrated improvement of their visual acuity. Compared with a recent meta-analysis by Satti and Chaudry in 2015, our results demonstrated a higher technical success rate and lower complication rates. Our study findings support the paradigm shift from CSF diversion procedures to venous sinus stenting in patients with IIH who fail first-line therapy. Venous sinus stenting has a high technical success rate and significantly lower complication rates than other invasive treatments.

Long-Term Cangrelor Administration in Neurology Intensive Care: A Case Series.

Cangrelor is a P2Y12 inhibitor antiplatelet agent, with a rapid onset and offset. The available literature only reviews short-term administration over a few hours. We describe 5 patients who received cangrelor for >1 month in a neurosurgical intensive care unit due to a very high likelihood of requiring emergency revision surgery. Despite multiple therapeutic interruptions for surgical procedures, no hemorrhagic events occurred, and there was only one transient ischemic event, which occurred during transition from cangrelor to ticagrelor. Cangrelor can be a therapeutic option for patients with a high likelihood of requiring revision neurosurgery after intracranial stenting.

Preclinical model of anterior circulation intracranial stenting

BackgroundPreclinical testing of intracranial stents is currently performed in the peripheral circulation, and rarely in the basilar artery of the dog.ObjectiveTo test the feasibility of intracranial stenting in the middle...