TICI 2b Research Articles

Clinical comparison of aspiration to stentriever-mediated aspiration thrombectomy for M2 occlusions

ObjectiveWhile revascularization for M2 occlusions is generally recommended and considered beneficial, the optimal approach (aspiration vs stentriever/combined) is less well defined in the literature. We sought to compare outcomes after thrombectomy with manual aspiration thrombectomy alone (MAT) or stentriever-mediated aspiration thrombectomy (SMAT) Materials and MethodsTo circumvent inter-operator technical variability, patients underwent thrombectomy for M2 occlusions by a single operator and were stratified by first pass approach: manual aspiration thrombectomy (MAT/aspiration alone) and stentriever-mediated manual aspiration thrombectomy (SMAT/combination). Efficacy outcomes included good reperfusion (mTICI score ≥2b) and a favorable 90-day functional outcome (mRS score of ≤2). Safety outcomes included 90-day mortality and symptomatic intracranial hemorrhage. ResultsOne hundred three patients were identified: 57 underwent MAT whereas 46 underwent SMAT. Good reperfusion (TICI 2b or greater) was comparable between groups (93.5 % vs. 87.7 %, P=0.33). The intracranial hemorrhage rate was higher with SMAT compared to MAT (13 % vs. 1.8 %, P=0.04). Puncture-to-recanalization time was longer in SMAT (34.4 vs. 19.9 minutes, P<0.001). In multivariable analysis, complete or good reperfusion was associated with shorter puncture-recanalization time (adjusted odds ratio [aOR], 0.85) or less total passes (aOR, 0.58), respectively. In a propensity score matched analysis of 66 patients with comparable baseline and technical efficiency, the safety outcomes were not different between SMAT and MAT groups. ConclusionsSMAT compared with MAT did not result in an improved revascularization rate or functional outcome, while it was related to more hemorrhagic complications and mortality. Given cost and time savings with manual aspiration alone, this approach may be optimal as first line for M2 occlusions.

Stent Retriever AssIsted Lysis Technique with Tirofiban: A Potential Bailout Alternative to Angioplasty and Stenting.

Angioplasty and stent placement have been described as a bailout technique in individuals with failed thrombectomy. We aimed to investigate Stent retriever AssIsted Lysis (SAIL) with tirofiban before angioplasty and stent placement. Patients from 2 comprehensive stroke centers were reviewed (2020-2023). We included patients with failed thrombectomy and/or underlying intracranial stenosis who received SAIL with tirofiban before the intended angioplasty and stent placement. SAIL consisted of deploying a stent retriever through the occluding lesion to create a bypass channel and infuse 10 mL of tirofiban for 10 minutes either intra-arterially or IV. The stent retriever was re-sheathed before retrieval. The primary end points were successful reperfusion (expanded TICI 2b-3) and symptomatic intracerebral hemorrhage. Additional end points included 90-day mRS 0-2 and mortality. After a median of 3 (interquartile range, 2-4) passes, 44 patients received the SAIL bridging protocol with tirofiban, and later they were considered potential candidates for angioplasty and stent placement bailout (43.2%, intra-arterial SAIL). Post-SAIL successful reperfusion was obtained in 79.5%. A notable residual stenosis (>50%) after successful SAIL was observed in 45.7%. No significant differences were detected according to post-SAIL: successful reperfusion (intra-arterial SAIL, 80.0% versus IV-SAIL, 78.9%; P = .932), significant stenosis (33.3% versus 55.0%; P = .203), early symptomatic re-occlusion (0% versus 8.0%; P = .207), or symptomatic intracerebral hemorrhage (5.3% versus 8.0%; P = .721). Rescue angioplasty and stent placement were finally performed in 15 (34.1%) patients (intra-arterial SAIL 21.0% versus IV-SAIL 44%; P = .112). At 90 days, mRS 0-2 (intra-arterial SAIL 50.0% versus IV-SAIL 43.5%; P = .086) and mortality (26.3% versus 12.0%; P = .223) were also similar. In patients with stroke in which angioplasty and stent placement are considered, SAIL with tirofiban, either intra-arterial or IV, seems to safely induce sustained recanalization, offering a potential alternative to definitive angioplasty and stent placement.

Predictors of symptomatic intracerebral hemorrhage after endovascular treatment for acute ischemic stroke due to tandem lesion in anterior circulation

BackgroundEndovascular treatment (EVT) of tandem lesion (TL) in the anterior circulation acute ischemic stroke (IS) usually requires periprocedural antithrombotic treatment and early initiation of dual antiplatelet therapy (DAPT) after carotid stenting. However, it may contribute to an occurrence of symptomatic intracerebral hemorrhage (SICH) in some cases. We investigated factors influencing the SICH occurrence and assessed the possible predictors of SICH after EVT. MethodsIS patients with TL in the anterior circulation treated with EVT were enrolled in the multicenter retrospective ASCENT study. A good three-month clinical outcome was scored as 0–2 points in modified Rankin Scale (mRS) and recanalization using the TICI scale. SICH was assessed using the SITS-MOST criteria. Logistic regression analysis was used for the assessment of possible predictors of SICH with adjustment for potential confounders. ResultsIn total, 300 (68.7 % males, mean age 67.3 ± 10.2 years) patients with median of admission NIHSS 17 were analyzed. Recanalization (TICI 2b-3) was achieved in 290 (96.7 %) patients and 176 (58.7 %) had mRS 0–2. SICH occurred in 25 (8.3 %) patients. Patients with SICH did not differ from those without SICH in the rate of periprocedural antithrombotic treatment (64 vs. 57.5 %, p = 0.526) and in the rate of DAPT started within the first 12 h after EVT (20 vs. 42.2 %, p = 0.087). After adjustment, admission NIHSS and admission glycemia were found as the only predictors of SICH after EVT. ConclusionAdmission NIHSS and glycemia were found as the only predictors of SICH after EVT for TL. No associations between periprocedural antithrombotic treatment, early start of DAPT after EVT and SICH occurrence were found.

Role of Endovascular Thrombectomy in Improving the Functional Outcome in Acute Stroke Patients Presenting 6-12 Hours after Stroke Onset

Abstract Background Based on the World Health Organization (WHO) statistics, there are 15 million strokes annually. The aim of the treatment in acute ischemic stroke is rapid restoration of perfusion to the ischemic area by minimizing the time between the occurrence of symptoms and the treatment. This is crucial for saving the salvageable brain tissue (penumbra) by restoration of flow and metabolism to normal Aim of Work The aim of work is to evaluate the safety and efficacy of endovascular thrombectomy (EVT) in patients presenting 6-12 hours from onset of stroke symptoms secondary to large vessel occlusion. Patients and Methods 50 Patients presenting with acute ischemic stroke with causative occlusion of major vessels in anterior circulation, underwent mechanical thrombectomy Results Two-thirds of the patients had their intracranial arterial occlusion at M1 segment of the middle cerebral artery. The median baseline NIHSS score, ASPECTS, and mRS score of the studied patients was 16 (IQR 11-20), 8 (IQR 7-9) and 0 (IQR 0-1), respectively. The median final infarct volume, NIHSS score, ASPECTS post-intervention and mRS score at 90 days of the studied patients was 40 ml (IQR 26.5-70) (P &amp;lt; 0.001), 9 (IQR 4-16) (P &amp;lt; 0.001), 8(IQR 5-9) (P &amp;lt; 0.01), and 2 (IQR1-4) (P &amp;lt; 0.001), respectively and (90 %) of them had revascularization type TICI 2b- 3. More than half of the studied patients (52%) had mRS score at 90 days of ≤ 2 and mortality rate was 12%. Conclusions The current study showed that endovascular thrombectomy techniques are safe and effective in the treatment of acute ischemic stroke.

Impact and determinants of door in-door out time for stroke thrombectomy transfers in a large hub-and-spoke network.

The mantra "time is brain" cannot be overstated for patients suffering from acute ischemic stroke. This is especially true for those with large vessel occlusions (LVOs) requiring transfer to an endovascular thrombectomy (EVT) capable center. We sought to evaluate the spoke hospital door in-door out (DIDO) times for patients transferred to our hub center for EVT. Individuals who first presented with LVO to a spoke hospital and were then transferred to the hub for EVT were retrospectively identified from a prospectively maintained database from January 2019 to November 2022. DIDO was defined as the time between spoke hospital door in arrival and door out exit. Baseline characteristics, treatments, and outcomes were compared, dichotomizing DIDO at 90 minutes based in the American Heart Association goal for DIDO ≤90 minutes for 50% of transfers. Multivariable regression analyses were performed for determinants of the 90-day ordinal modified Rankin Scale (mRS) and DIDO. We identified 194 patients transferred for EVT with available DIDO. The median age was 67 years (IQR 57-80), and 46% were female. The median National Institutes of Health Stroke Scale (NIHSS) was 16 (10-20), 50% were treated with intravenous thrombolysis at a spoke, and TICI 2B-3 reperfusion was achieved in 87% at the hub. The median DIDO was 120 minutes (97-149), with DIDO ≤90 minutes achieved in 18%. DIDO was a significant determinant of 90-day ordinal mRS (B = 0.007, 95% CI = 0.001-0.012, p = 0.013), even when accounting for the last known well-to-spoke door in, spoke door out-to-hub arrival, hub arrival-to-puncture, puncture-to-first pass, age, NIHSS, intravenous thrombolysis, TICI 2B-3, and symptomatic intracranial hemorrhage. Importantly, determinants of DIDO included Black race or Hispanic ethnicity (B = 0.918, 95% CI = 0.010-1.826, p = 0.048), atrial fibrillation or heart failure (B = 0.793, 95% CI = 0.257-1.329, p = 0.004), and basilar LVO location (B = 2.528, 95% CI = 1.154-3.901, p < 0.001). Spoke DIDO was the most important period of time for long-term outcomes of LVO stroke patients treated with EVT. Targets were identified to reduce DIDO and improve patient outcomes.

Effect of early vs. delayed extubation on functional outcome among patients with acute ischemic stroke treated with endovascular thrombectomy under general anesthesia: the prospective, randomized controlled EDESTROKE trial study protocol

BackgroundRecent meta-analyses and randomized studies have shown that among patients with acute ischemic stroke undergoing endovascular thrombectomy, general anesthesia with mechanical ventilation is associated with better functional status compared to local anesthesia and sedation, and they recommend its use. But once the procedure is completed, when is the optimal moment for extubation? Currently, there are no guidelines recommending the optimal moment for extubation. Prolonged mechanical ventilation time could potentially be linked to increased complications such as pneumonia or disturbances in cerebral blood flow due to the vasodilatation produced by most anesthetic drugs. However, premature extubation in a patient who has suffered a stroke could led to complications such as agitation, disorientation, abolished reflexes, sudden fluctuations in blood pressure, alterations in cerebral blood flow, respiratory distress, bronchial aspiration, and the need for reintubation. We therefore designed a randomized study hypothesizing that early compared with delayed extubation is associated with a better functional outcome 3 months after endovascular thrombectomy treatment under general anesthesia for acute ischemic stroke.MethodsThis investigator-initiated, single-center, prospective, parallel, evaluated blinded, superiority, randomized controlled trial will include 178 patients with a proximal occlusion of the anterior circulation treated with successful endovascular thrombectomy (TICI 2b-3) under general anesthesia. Patients will be randomly allocated to receive early (< 6 h) or delayed (6–12 h) extubation after the procedure. The primary outcome measure is functional independence (mRS of 0–2) at 90 days, measured with the modified Rankin Score (mRS), ranging from 0 (no symptoms) to 6 (death).DiscussionThis will be the first trial to compare the effect of mechanical ventilation duration (early vs delayed extubation) after satisfactory endovascular thrombectomy for acute ischemic stroke under general anesthesia.Trial registrationThe study protocol was approved April 11, 2023, by the by the Santiago-Lugo Research Ethics Committee (CEI-SL), number 2023/127, and was registered into the clinicaltrials.gov clinical trials registry with No. NCT05847309. Informed consent is required. Participant recruitment begins on April 18, 2023. The results will be submitted for publication in a peer-reviewed journal and presented at one or more scientific conferences.

Utilizing a Guiding Catheter to Improve Endovascular Therapy Outcomes for Acute Vertebrobasilar Artery Occlusion in Patients with Tortuous Vessels.

Objective Stable and swift placement of a guiding catheter in endovascular therapies for acute vertebrobasilar artery occlusion is often difficult because of the tortuous bends of the vertebral or subclavian artery especially in older people. The use of a delivery assist guiding catheter (DAGC) shortens the time with stable support to deliver a therapeutic treatment catheter to the target lesions. Herein, we reported the clinical and radiographic outcomes in endovascular therapies utilizing the DAGC for acute vertebrobasilar artery occlusions in actual clinical settings. Materials and Methods Between January 2018 and December 2021, 33 consecutive patients (males, 20[60.6%]; median age, 78 years) using a DAGC for acute vertebrobasilar artery occlusion were analyzed retrospectively. Reperfusion was graded using postinterventional angiograms based on the "thrombolysis in cerebral infarction" (TICI) classification. Furthermore, the time from puncture to recanalization and the rate of effective recanalization achievement were investigated. Results Effective recanalization with TICI 2b or 3 was achieved in 28 (84.8%) patients, and the median time from puncture to recanalization was only 44 minutes, despite the high rate of older patients in our cohort. In contrast, asymptomatic intracranial hemorrhage as a complication was observed in only 3 (9.1%) patients. Conclusion The DAGC contributes to the shortening of recanalization time and improves the outcomes of endovascular therapies for acute vertebrobasilar artery occlusion.

Thrombectomy using Zoom Reperfusion System in pediatric acute ischemic strokes: Case series and literature review.

Zoom reperfusion system (Imperative Care, CA) has proven to be promising for use in adult mechanical thrombectomies (MTs) but has not been described in pediatrics. We present two cases of a 14-year-old with acute right middle cerebral artery (MCA) syndrome and a 10-year old with acute left MCA syndrome who underwent MT using Zoom Reperfusion System safely with TICI 2B and TICI 3 recanalization, respectively. Case report and literature review. A 14-year-old healthy boy with right supraclinoid internal carotid artery (ICA) occlusion (case 1) and a 10-year-old boy with left hypoplastic heart syndrome and left ICA terminus occlusion (case 2) were taken for MT after receiving alteplase at our institution. Through femoral access, an 8-French sheath was introduced into the right femoral artery through which a Zoom 88 catheter was introduced and parked at the right petrous ICA segment in case 1 and left ophthalmic ICA segment in case 2. Angiogram demonstrated complete ICA occlusion just past the ophthalmic artery origin in case 1 and at the ICA terminus in case 2. Zoom system (88 and 71) was then navigated to the face of clot with vacuum manifold engaged with the clot. TICI 2B (with the help of Trevo stent retriever [Stryker]) and TICI 3 recanalization were achieved in cases 1 and 2, respectively. The use of Zoom reperfusion system could potentially be feasible for use in pediatric age group. Larger pediatric patient population is needed to establish its safety.

Intracranial aneurysms in patients with acute ischemic stroke prevalence and influence on mechanical thrombectomy over 14 years in a tertiary-care center

IntroductionThe prevalence of intracranial aneurysms (IA) in patients with acute ischemic stroke (AIS) requiring mechanical thrombectomy (MT) is unclear. ObjectiveTo describe the prevalence of IA in patients with AIS and their influence on MT. Materials & methodsThis is a retrospective cohort study on all patients admitted with a diagnosis of AIS from January 2008 to March 2022 at a tertiary academic center. The records were reviewed for demographic, clinical, imaging, and outcomes data. Only patients who had CTA at admission were included in this analysis. ResultsAmong 2265 patients admitted with AIS, this diagnosis was confirmed in 2113 patients (93.3 %). We included 1111 patients (52.6 %) who had head CTA and 321 (28.9 %) who underwent MT. The observed prevalence of aneurysms on CTA was 4.5 % (50/1111 patients), and 8 (16 %) had multiple aneurysms. MT was performed in 7 patients harboring IAs: 6 ipsilateral (5 proximal and 1 distal to the occlusion)and 1 contralateral aneurysm.. The patient with a contralateral aneurysm had a TICI 2B score In patients with ipsilateral aneurysms, TICI 2B or 3 was achieved in 3 cases (50 %), which is significantly lower than historical control of MT (91.6 %) without IA (p = 0.01). No aneurysms ruptured during MT. The aneurysm noted distal to the occlusion was mycotic. ConclusionIn this analysis, the observed prevalence of IA in patients with AIS was 4.5%. Ipsilateral aneurysms (proximal or distal to the occlusion site) deserve particular attention, given the potential risk of rupture during MT. Aneurysms located distal to the occlusion were mycotic and the rate of recanization in patients with ipsilateral aneurysms was low compared to historical controls. Further studies are needed to improve the outcomes in patients with IA requiring MT.

Hyperglycemia Is Associated With Computed Tomography Perfusion Core Volume Underestimation in Patients With Acute Ischemic Stroke With Large-Vessel Occlusion.

CT Perfusion (CTP) predictions of infarct core play an important role in the determination of treatment eligibility in large vessel occlusion (LVO) acute ischemic stroke (AIS). Prior studies have demonstrated that blood glucose can affect cerebral blood flow (CBF). Here we examine the influence of acute and chronic hyperglycemia on CTP estimations of infarct core. From our prospectively collected multi-center observational cohort, we identified patients with LVO AIS who underwent CTP with RAPID (IschemaView, Stanford, CA) post-processing, followed by endovascular therapy with substantial reperfusion (TICI 2b-3) within 90 minutes, and final infarct volume (FIV) determination by MRI 48-72 hours post-treatment. Core volume over- and under-estimations were defined as a difference of at least 20 mL between CTP-RAPID predicted infarct core and DWI FIV. Primary outcome was the association of presentation glucose and HgbA1c with underestimation (UE) of core volume and was measured using multivariable logistic regression adjusted for comorbidities and presentation characteristics. Secondary outcomes included frequency of overestimation (OE) of infarct core. Among 256 patients meeting inclusion criteria, median age was 67 [IQR 57-77], 51.6% were female, and 132 (51.6%) and 93 (36.3%) had elevated presentation glucose and elevated HgbA1c, respectively. Median CTP-predicted core was 6 mL [IQR 0-30], median DWI FIV was 14 mL [IQR 6-43] and median difference was 12 mL [IQR 5-35]. Twenty-eight (10.9%) patients had infarct core OE and 68 (26.6%) had UE. Compared to those with no UE, patients with UE had elevated blood glucose (median 119 [103-155] vs 138 [117-195], p=0.002) and HgbA1c (median 5.80 [5.40-6.40] vs 6.40 [5.50-7.90], p=0.009). In multivariable analysis, UE was independently associated with elevated glucose (aOR 2.10, p=0.038) and HgbA1c (aOR 2.37, p=0.012). OE was associated with lower presentation blood glucose (median 109 [ 99-132] in OE vs 127 [107-172] in no OE, p=0.003) and HgbA1c (5.6 [IQR 5.1 - 6.2] in OE vs 5.90 [5.50-6.70] in no OE, p=0.012). Acute and chronic hyperglycemia were strongly associated with CTP UE in patients with LVO AIS undergoing EVT. Glycemic state should be considered when interpreting CTP findings in patients with LVO AIS.

312 Mechanical Thrombectomy With or Without Intravenous Thrombolysis for Acute Ischemic Stroke Due to Distal and Medium Vessel Occlusions: A Propensity Score Matching of Patients From 41 Academic Centers

INTRODUCTION: To date, studies evaluating mechanical thrombectomy (MT) in distal and medium vessel occlusions (DMVOs) have failed to establish conclusive, high-quality evidence for its clinical benefit. METHODS: Between January 2017 and January 2022, characteristics and outcomes of patients with DMVOs treated with MT or MT + IVtPA were collected at 41 academic centers in North America, Asia, and Europe. Using R software version 4.2.3, propensity score matching using the nearest neighbor matching by controlling for all relevant variables, followed by appropriate descriptive statistics and multivariate logistic regression. RESULTS: After propensity score matching, all differences between groups were resolved, and there was a total of 577 patients included (315 MT alone and 262 MT +IVT). Patients treated with MT + IVT achieved greater rates of TICI 2b-3 (OR = 1.79, 95% CI = 1.02-3.15; P-value= 0.043) than those treated with MT alone, and the rate of modified Rankin score (mRS) 0-2 was greater in the MT + IVT group (n = 171, 65.3%) compared to the MT alone (n = 181, 57.5%) group (OR = 1.52, 95% CI= 1.03-2.24; p-value = 0.034). Sixty-nine patients experienced 90-day mortality, and the rate was comparable between the MT + IVtPA group (n = 30, 11.5%) and the MT alone (n = 39, 12.4%) group (OR = 0.9, 95% CI = 0.53-1.54; p-value = 0.71). Of note, the rate of intracranial hemorrhage (all types) was similar between the MT + IVtPA and MT alone group (OR = 0.85, 95% CI = 0.58-1.26; p-value = 0.43). CONCLUSIONS: MT + IVT showed higher efficacy than MT alone in patients with DMVOs, without higher risks.

1249 Single-Center Outcomes of Onyx Frontier and Resolute Onyx Drug-Eluting Balloon Mounted Stents for Rescue Stenting for Acute Large Vessel Occlusion

INTRODUCTION: Mechanical thrombectomy (MT) is a common treatment for large vessel occlusions with recent literature expanding its indications. In cases where MT fails, rescue stenting may be necessary to achieve reperfusion; however, the absence of standardized techniques or devices poses a challenge. METHODS: A retrospective chart review was performed of all patients who underwent rescue stenting, in the setting of MT, using Onyx Frontier or Resolute Onyx stents at a single institution. Technical details, procedural complications, and patient outcomes were recorded for each case. RESULTS: In total, 21 Onyx Frontier and Resolute Onyx stents were deployed in 18 patients undergoing rescue stenting. Among these, 13 involved the use of Resolute Onyx stents, while 5 cases utilized Onyx Frontier stents. Stent locations included the middle cerebral artery (40%), internal carotid artery (15%), vertebral artery (20%), and basilar artery (25%). The average NIHSS score before MT was 13.83 (range 0-31). The median initial mRS score was 0, while the median mRS score at follow-up was 3. Successful reperfusion, as assessed by TICI scores, was achieved in 43.8% of patients for TICI 3, 43.8% for TICI 2C, and 12.5% for TICI 2B. The average proximal vessel diameter was 2.31 mm, and the most used stent length was 12 mm. Post-revascularization, 33% of patients experienced hemorrhage, of which only one patient (16.7%) had symptomatic hemorrhage due to vessel rupture necessitating hemicraniectomy. CONCLUSIONS: Onyx Frontier and Resolute Onyx stents are well-suited for rescue stenting in cases where aspiration and stentriever techniques fail during MT. These balloon-mounted drug-eluting stents exhibit excellent navigability, rendering them appropriate for rescue revascularization procedures. Our findings demonstrate that these stents confer a high degree of technical success and a low rate of intra- and post-procedural complications.

Assessment of the safety and efficacy of the Zoom 45 and 55 reperfusion catheters for medium and distal mechanical thrombectomies: A multi-institutional study

IntroductionThe Zoom aspiration catheters harbor novel dimensions and construction to enhance trackability and deliverability. In addition, a beveled tip may improve thrombus interaction and aspiration force for a set inner diameter. This study evaluates their utility in medium and distal vessel occlusions. ObjectiveTo evaluate the safety and efficacy of Zoom 45 and 55 aspiration catheters in medium and distal vessel thrombectomy. MethodsPatients treated for distal vessel occlusions via mechanical thrombectomy utilizing either the Zoom 45/55 catheter or a historical control catheter between 2021–2022 at two institutions were included in this study. Medium and distal occlusions were defined as any anterior or posterior cerebral artery branch as well as the M2-4 segment of the middle cerebral artery (MCA). Preprocedural, procedural, and postprocedural variables were obtained. ResultsThirty-eight patients underwent thrombectomy with Zoom 45 or 55 catheters; four had multiple occluded vessels. Occlusion location included the M2 in 32 cases, M3-4 in 7 cases, A2 in 2 cases and P2 in 1 case. The mean number of passes per occlusion was 1.6 and overall successful reperfusion (TICI 2b or greater) was achieved in 84 % of cases. There were no symptomatic procedure-related complications such as perforation or post-procedural symptomatic ICH. Modified Rankin scores rates of 0–2, 3–5, and 6 at three months post-procedure were 35.7 %, 21.4 %, and 42.9 %, respectively. ConclusionsThe Zoom beveled tip aspiration catheters are safe and effective for more challenging medium and distal vessel occlusions.

Incidence and clinical outcomes of perforations during mechanical thrombectomy for medium vessel occlusion in acute ischemic stroke: A retrospective, multicenter, and multinational study.

Mechanical thrombectomy (MT) has revolutionized the treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO), but its efficacy and safety in medium vessel occlusion (MeVO) remain less explored. This multicenter, retrospective study aims to investigate the incidence and clinical outcomes of vessel perforations (confirmed by extravasation during an angiographic series) during MT for AIS caused by MeVO. Data were collected from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. A total of 1373 AIS patients with MeVO underwent MT. Baseline characteristics, procedural details, and clinical outcomes were analyzed. The incidence of vessel perforation was 4.8% (66/1373). Notably, our analysis indicates variations in perforation rates across different arterial segments: 8.9% in M3 segments, 4.3% in M2 segments, and 8.3% in A2 segments (p = 0.612). Patients with perforation had significantly worse outcomes, with lower rates of favorable angiographic outcomes (TICI 2c-3: 23% vs 58.9%, p < 0.001; TICI 2b-3: 56.5% vs 88.3%, p < 0.001). Functional outcomes were also worse in the perforation group (mRS 0-1 at 3 months: 22.7% vs 36.6%, p = 0.031; mRS 0-2 at 3 months: 28.8% vs 53.9%, p < 0.001). Mortality was higher in the perforation group (30.3% vs 16.8%, p = 0.008). This study reveals that while the occurrence of vessel perforation in MT for AIS due to MeVO is relatively rare, it is associated with poor functional outcomes and higher mortality. The findings highlight the need for increased caution and specialized training in performing MT for MeVO. Further prospective research is required for risk mitigation strategies.

Endovascular thrombectomy for DAWN- and DEFUSE-3 ineligible acute ischemic stroke patients: a systematic review and meta-analysis.

Endovascular therapy (EVT) has been proven beneficial for treating acute ischemic strokes (AIS) with large vessel occlusion (LVO). Recent trials of DAWN and DEFUSE-3 have extended the treatment window to 6-24 h, sparking investigations into EVT outcomes for patients not eligible for DAWN/DEFUSE-3 criteria. To assess the outcomes of endovascular therapy (EVT) for late-window anterior circulation large vessel occlusion (LVO) in acute ischemic stroke patients, comparing DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND) groups. This systematic review and meta-analysis examined EVT outcomes for patients with late-window anterior circulation LVO beyond 6 h. We categorized patients as DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND). Our search covered PubMed, Embase, Web of Science, and Scopus. A total of 464 records were initially identified. After duplicate removal, 298 studies were screened. Nine studies were included and analyzed. Our analysis focused on study characteristics, baseline comparisons, risk of bias, and outcomes. Baseline characteristics showed comparable age, gender, most comorbidities, NIHSS score, and ASPECTS between DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND) patients. NDND patients' history showed a higher rate of atrial fibrillation and larger infarct volumes on baseline imaging. Successful reperfusion rates (TICI 2b-3) were similar between DD and NDND with 354 out of 469 in the DD group and 364 out of 459 in the NDND group (OR = 0.86; 95% CI 0.40, 1.84; p = 0.689), though with significant heterogeneity (I2 = 73%; P = 0.002). The proportion of patients with distal occlusions was significantly higher in the NDND group as compared to the DD group (137 (39.4%) of 347 patients versus 47 (11%) of 428 patients, respectively), with significant heterogeneity across studies (I2 = 85%, p = 0.023). Functional independence at 90 days (mRS 0-2) showed no significant difference between groups with 259 out of 802 in the DD group and 197 out of 668 in the NDND group (OR = 1.12; 95% CI 0.77, 1.63; p = 0.552) but also exhibited notable heterogeneity (I2 = 46%, p = 0.063). Symptomatic intracranial hemorrhage (sICH) rates were lower in DD with 14 out of 309 in the DD group and 47 out of 400 in NDND group (OR = 0.49; 95% CI 0.25, 0.93; p = 0.029) as compared to the NDND patients, showing no heterogeneity (I2 = 0%, p = 0.552). 90-day mortality was lower in DD with 43 out of 304 in the DD group and 107 out of 399 in the NDND group (OR = 0.55; 95% CI 0.37, 0.82; p = 0.004) as compared to NDND patients, with no significant heterogeneity (I2 = 0%, p = 0.536). This meta-analysis demonstrates equivalent rates of functional independence between DD and NDND patients. However, the high proportion of distal occlusions and higher rates of sICH and mortality in NDND patients suggest caution in offering mechanical thrombectomy to DAWN/DEFUSE-3 ineligible patients. A more flexible approach to EVT eligibility criteria could benefit select patients in real-world practice. Nonetheless, further research is needed to identify which patients would benefit from expanded EVT eligibility criteria.

Abstract TP212: 2b or Not 2b? TICI 2b Reperfusion Score in Endovascular Thrombectomy for Acute Ischemic Stroke Carries a Poor Functional Outcome

Background: Endovascular thrombectomy (EVT) for treatment of acute ischemic stroke (AIS) in the proximal cerebrovasculature has, since its inception, become part of the standard of care when addressing AIS. Overall, one in six individuals treated has improved neurologic and functional outcomes. Reperfusion following thrombectomy in the anterior cerebral circulation has long been graded by the modified Thrombolysis in Cerebral Infarction (mTICI) scale-and the score of mTICI (2b, or, “partial filling of more than 50% of the affected vascular territory” is considered the benchmark for “good” outcomes in EVT. It remains unclear whether this score at time of reperfusion reliably predicts a sustained improvement in neurologic or functional outcome. Method: This is a retrospective review of all anterior AIS patients with large vessel occlusion (LVO) at Barrow Neurological Institute between 01/01/2018 and 12/31/2022 who underwent EVT with mTICI 2b or greater. The study was approved by the local IRB. Demographic data of patients between the ages of 18 and 95 who had AIS with LVO in the anterior Circle of Willis or its supplying vessels were collected. Other variables collected and analyzed include mTICI score, and modified Rankin Score (mRS) at discharge and 90 days. The TICI grade was obtained via digital cerebral angiography post EVT. Descriptive statistics was used to examine the differences of mRS scores at 90 days. Results: Of 81 cases reviewed, 52 (65%) had a TICI 2b score and their average mRS was 3.7, 20 (25%) had a TICI 2c and their average mRS was 3.6, and 4 (5%) had a TICI 3 with mRS 3 at discharge. At 90 days, the average mRS for TICI 2b patients was 3.2, for TICI 2c patients 2.9 and for TICI 3 patients 2.3. No difference in the rate of intracerebral hemorrhage (ICH) following reperfusion between the TICI 2 and 3 groups (17%). Conclusion: Our results demonstrated that patients with a mTICI of 2b had a higher mean mRS at discharge and minimal improvement of mRS at 90 days compared against patients with a mTICI of 2c or 3 (average change in score was -0.6, -0.7 and -1.3 in the TICI 2b, 2c and 3 groups respectively). Therefore, a reperfusion score of mTICI 2b may not be sufficient to indicate a high probability of a good functional outcome. With EVT, reaching a TICI 3 should be attempted.

Abstract WP191: Impact and Determinants of Door In-Door Out Time for Stroke Thrombectomy Transfers: Real World Analysis of a Large Hub-and-Spoke Network

Introduction: The mantra ‘time is brain’ cannot be overstated for patients suffering from acute ischemic stroke. This is especially true for those with large vessel occlusions (LVO) requiring transfer to an endovascular thrombectomy (EVT) capable center. We sought to evaluate the spoke hospital door in-door out (DIDO) times for patients transferred to our hub center for EVT. Methods: Individuals who first presented with LVO to a spoke hospital and were then transferred to the hub for EVT were retrospectively identified from a prospectively maintained database from January 2019 to November 2022. DIDO was defined as the time between spoke hospital door in arrival and door out exit. Baseline characteristics, treatments, and outcomes were compared, dichotomizing DIDO at 90 min based in the American Heart Association goal for DIDO ≤90 min for 50% of transfers. Multivariable regression analyses were performed for determinants of 90-day ordinal modified Ranking Scale (mRS) and DIDO. Results: We identified 194 patients transferred for EVT with available DIDO. The median age was 67 (IQR 57-80), and 46% were female. The median NIHSS was 16 (10-20), 50% were treated with intravenous thrombolysis at a spoke, and TICI 2B-3 reperfusion was achieved in 87% at the hub. The median DIDO was 120 min (97-149), with DIDO ≤90 min achieved in 18%. DIDO was a significant determinant of 90-day ordinal mRS (B=0.007, 95%CI=0.001-0.012, p=0.013), even when accounting for last known well-to-spoke door in, spoke door out-to-hub arrival, hub arrival-to-puncture, puncture-to-first pass, age, NIHSS, intravenous thrombolysis, TICI 2B-3, and symptomatic intracranial hemorrhage. Importantly, determinants of DIDO included Black race or Hispanic ethnicity (B=0.918, 95%CI=0.010-1.826, p=0.048), atrial fibrillation or heart failure (B=0.793, 95%CI=0.257-1.329, p=0.004), and basilar LVO location (B=2.528, 95%CI=1.154-3.901, p&lt;0.001). Conclusion: In this real-world analysis of a large hub-and-spoke network, spoke DIDO was the most important period of time for long term outcomes of LVO stroke patients treated with EVT. Determinants of DIDO were identified which require further investigation and motivate system changes that may reduce DIDO and improve patient outcomes.

Abstract WP193: Endovascular Thrombectomy for DAWN- and DEFUSE 3 Ineligible Acute Ischemic Stroke Patients: A Systematic Review and Meta-Analysis

Background: The current evidence supports the benefits of endovascular treatment (EVT) in acute ischemic stroke (AIS) with large vessel occlusion (LVO). The DAWN and DEFUSE-3 trials expanded the EVT window up to 24 hours. A few real-world studies explored EVT outcomes in DAWN/DEFUSE-3 ineligible (NDND) patients. Methods: This meta-analysis investigated EVT outcomes in patients with late-window anterior circulation LVO, including both DAWN/DEFUSE-3 eligible (DD) and NDND patients. Nine studies were included, focusing on study characteristics, risk of bias, and outcomes. Results: Baseline characteristics showed comparable age, gender, comorbidities, NIHSS score, and ASPECTS between DD and NDND patients. NDND patients exhibited larger infarct volumes and higher atrial fibrillation rate. Successful reperfusion rates (TICI 2b-3) were comparable between the two groups (OR= 0.86; 95% CI= 0.40, 1.84; p = 0.689), with significant heterogeneity (I 2 = 73%; P = 0.002). Functional independence (90-day mRS score 0-2) was not significantly different between the two groups (OR= 1.12; 95% CI= 0.77, 1.63; p = 0.552) with notable heterogeneity (I 2 = 46%, p = 0.063). Symptomatic intracranial hemorrhage (sICH) rate was lower in the DD group as compared to NDND patients (OR= 0.49; 95% CI= 0.25, 0.93; p = 0.029) with no heterogeneity (I 2 = 0%, p = 0.552). 90-day mortality was lower in the DD group than in the NDND group (OR= 0.55; 95%-CI= 0.37, 0.82; p = 0.004) with no significant heterogeneity (I 2 = 0%, p = 0.536). Conclusion: While this meta-analysis showed comparable rates of functional independence between DD and NDND patients, the potential bias introduced by the higher rates of sICH and mortality in the latter group should prompt great care when offering EVT to NDND patients. Less restricted EVT eligibility criteria might yield positive outcomes in real-world practice in specific patients. However, increased risks of sICH and mortality in NDND patients warrant further investigation to optimize the risk-benefit balance in expanding EVT eligibility criteria.

Abstract WP2: Natural History of Large Vessel Occlusion Patients Presenting With Minor Stroke Symptoms

Background: Acute ischemic stroke is a leading cause of mortality and disability in the US, with 50% of patients with minor stroke symptoms (MSS). Large vessel occlusion (LVO) is found in 10% of MSS cases and predicts poor neurological outcomes. However, treatment strategies for MSS-LVO lack consensus, and a deeper understanding of the natural history of MSS-LVO is needed. Methods: We screened all patients presenting to a large stroke network, from May 2017 to August 2023, for intracranial anterior circulation LVO and MSS (NIHSS %lt 6). Descriptive statistics were applied to demographic, clinical, radiographic, and neurological outcomes data, including early neurological deterioration (END) (NIHSS gain 3+). Results: Ninety patients participated in the study, averaging 64.5 years old, with 58.8% male, 48.8% white, 22.2% black, and 16.2% Hispanic. Comorbidities included diabetes (23%), hypertension (67.7%), atrial fibrillation (22%), hyperlipidemia (53%), and smoking (40%). Patients arrived with mean 7 hours (SE 1.6) from LKW, and a mean NIHSS 3.95 (SE 0.40). The majority of patients had baseline mRS of 0-2 (92.6%). Occlusion sites included M1 (38.9%), M2 (40%), and ICA terminus (2.2%). The mean ASPECTS score was 9.4 (SE 0.13). Immediate thrombolytic treatment was delivered to 34% of patients. Out of 90 patients, 31 (34%) suffered END, with mean NIHSS at END of 9.17 (SE 0.85), necessitating rescue endovascular thrombectomy (EVT). Collateral vessel failure caused 87.1% of END cases, clot migration 9.7%, and additional strokes 3.2%. Of the 31 EVT cases, 29 (93%) achieved TICI 2b-3, averaging 3.1 (SE 0.35) passes. ICH occurred in 5 patients; 2 had undergone EVT, although none were symptomatic. At 24 hours and 5 days from presentation, the mean NIHSS were 3.15 and 2.86 respectively, worse in END patients (6.16 vs 1.55, p=0.00, and 6.28 vs 1.14, p=0.00). After 30 days, only 66% of END patients had mRS of 0-2 compared to 84% of non-END patients (p=0.02). Similarly, at 90 days, only 65% of END patients, versus 86% of non-END patients, had mRS of 0-2 (p=0.02). Conclusion: The study details the natural history of MSS-LVO, showing a prominent incidence of EVT-requiring END due to collateral failure. Future research should identify high-risk END patients for tailored treatment.

Abstract WP208: Infarction Size Affects Clinical Outcomes in Emergent Carotid Artery Stenting With Mechanical Thrombectomy

Background: Management of large vessel occlusion with extensive ipsilateral internal carotid artery (ICA) occlusion is unknown. We evaluated patients who underwent emergent carotid artery stenting (CAS) of the ICA with mechanical thrombectomy (MT). Methods: We retrospectively collected baseline demographic, clinical, and radiographic data on 27 patients who presented as a stroke alert within 24 hours of symptoms and had extensive (from bifurcation to distal ICA) occlusion by computerized tomography angiography from 2019-2023 at our institution. All patients underwent CAS with MT and received dual antiplatelet therapy. We measured outcomes by: (1) development of symptomatic ICH at 24 hours, (2) mortality, (3) Modified Rankin Scale (mRS) at 90 days, and (4) change in NIHSS at 24 hours. Baseline characteristics were reported by descriptive statistics. Statistical analyses were completed using Fisher’s exact test, Wilcoxon rank sum test, and logistic regression. Differences were statistically significant at p &lt; 0.05. Results: The mean age for our cohort was 64.5 ± 10.62 and nine patients were females (33.3%). Sixteen had M1 (59.3%) while 10 had M2 occlusion (37%), 14 patients received IV tPA (51.9%), and mean NIHSS at presentation was 15.6 ± 5.99. All patients achieved TICI 2b or TICI 3 recanalization. In our cohort, patients with lower ASPECT score 7.4 ± 1.8 compared to those with higher ASPECT score 9.0 ± 1.0 were more likely to have symptomatic ICH ( p = 0.032), and higher odds of mortality OR = 0.496, 95% CI (0.261-0.945). The development of symptomatic ICH at 24 hours following procedure was associated with severe disability (mRS 4-6) at 90 days ( p = 0.032). Administration of intravenous tPA was significantly associated with improvement of 4 or more points on NIHSS at 24 hours ( p = 0.032), but not with symptomatic ICH ( p = 0.419). Age, NIHSS at presentation, systolic blood pressure, and diabetes mellitus were not associated with mortality or symptomatic ICH. Conclusion: The area of infarction at the time of presentation (ASPECT score) is an essential factor in stratifying patient selection for emergent CAS during MT in extensive internal carotid artery occlusion. Further studies are needed to evaluate infarction size for safe interventions.