Distal M1 Research Articles

Image-based visualization of stents in mechanical thrombectomy for acute ischemic stroke: Preliminary findings from a series of cases.

Mechanical thrombectomy is the most effective treatment for great cerebral artery embolization within a set time window. Typically, an arteriogram does not show the localization of the stent after release and whether a thrombus is captured or not. Thus, improving the visualization of a stent in interventional therapy will be helpful for clinicians. To analyze stent imaging findings to enhance clinicians' understanding of a special circumstance, wherein a Solitaire AB retrievable stent was visible during the imaging of a thrombus capture that improved the success rate of stent-based mechanical thrombectomy. This was a retrospective study with four acute ischemic stroke (AIS) patients who underwent stent-based mechanical thrombectomy. Patient 1 was a 64-year-old man admitted after 5 h of confusion; angiography revealed basilar artery occlusion. We inserted a stent into the left posterior cerebral artery-P2 segment and visualized the expanded stent that successfully captured a thrombus. Patient 2 was a 74-year-old man admitted with confusion, which lasted approximately 3 h. Angiography revealed a left middle cerebral artery (MCA)-M1 segment occlusion. A stent was deployed in the distal M2 segment, and we could visualize the stent by capturing the thrombus. Patient 3 was a 74-year-old woman admitted after experiencing left hemiplegia for 3 h. We deployed a stent at the distal right MCA-M2 segment, and the developing stent captured a large thrombus. Patient 4 was an 82-year-old man who presented with confusion for 3 h. A developing stent was placed in the distal left MCA-M1 segment, which captured a large thrombus and several fragmented thrombi. To the best of our knowledge, this is the first report of stent imaging in patients with AIS. We demonstrated the usefulness and substantial potential of stent imaging in stent-based mechanical thrombectomy for AIS.

Effect of race/ethnicity on arterial recanalization following intravenous thrombolysis in acute ischemic stroke patients

IntroductionSeveral reports have identified that clinical outcomes such as death or disability in acute ischemic stroke (AIS) patients following intravenous (IV) tissue plasminogen activator (tPA) treatment can vary according to race and ethnicities. We determined the effect of race/ethnicity on rates of arterial recanalization in AIS patients with large vessel occlusion (LVO) after IV tPA. MethodsWe analyzed 234 patients with LVO detected on computed tomographic angiography (CTA) who received IV tPA and subsequently underwent angiography for potential thrombectomy. The primary occlusion sites on CTA and digital subtracted angiography (DSA) were compared and a score was given to the level of recanalization with values ranging from 1 (complete recanalization), 2 (partial recanalization), or 3 (no recanalization).The effect of race/ethnicity were assessed for predicting vessel recanalization using the covariates of age, gender, time since stroke onset, tPA dose received, NIHSS (National Institute of Health Stroke Scale) score at baseline, and location of the occlusion, using logistic regression analysis. ResultsFive patients (2.1%) were Hispanic or Latino, 8 (3.4%) Asian, 24 (10.3%) African American, and 197 (84.2%) White. A total of 50% had a distal ICA/proximal M1 occlusion, 20% distal M1 occlusion, and 16% single M2 occlusion. At the primary occlusion site, 44 (18.8%) had complete recanalization on post IV tPA angiogram, 17 (7.3%) had partial recanalization, and 165 (70.5%) had no recanalization. We did not find any association between race/ethnicity and vessel recanalization post IV tPA (Nonwhite combined [OR=1.49, p=0.351]; Asian [OR=1.460, p=0.650]; African American [OR=1.508, p=0.415]; White [OR=0.672, p=0.351]; ethnicity (Hispanic or Latino) [OR= 1.008, p=0.374]); Occlusion location (OR=0.189, p<0.001). Final TICI scores and mRS at 90 days were similar among the different groups. ConclusionApproximately 19% of patients had complete recanalization after IV tPA, but race and ethnicity did not seem to have an effect on arterial recanalization. Arterial recanalization was only affected by location of occlusion.

Disconnection of a stent retriever's pushwire caught by an accordion-like deformed aspiration catheter during mechanical thrombectomy: illustrative case.

In mechanical thrombectomy for acute large vessel occlusion, a combined technique of using both a stent retriever and an aspiration catheter has been widely used. The authors report a case in which a stent retriever's pushwire and a microcatheter were caught and disconnected by an accordion-like deformed aspiration catheter. A 74-year-old man underwent mechanical thrombectomy for a left M1 occlusion. A stent retriever was deployed from the left M2 to the left distal M1, and an aspiration catheter was advanced to the left distal M1. When the stent retriever and microcatheter were pulled into the aspiration catheter at the distal M1 without releasing the deflection, traction resistance of the stent retriever occurred, and the aspiration catheter contracted and deformed like an accordion distal to the tip of the guiding catheter. The stent retriever's pushwire and the microcatheter were caught and disconnected. When a stent retriever is pulled into a flexible aspiration catheter in a case with vascular tortuosity, it may be caught by an accordion-like deformed aspiration catheter and disconnected. It is necessary to release the deflection of the aspiration catheter once traction resistance of the stent retriever and deflection of the aspiration catheter occur.

Ischemic stroke in the setting of supratherapeutic International Normalized Ratio following coronavirus disease 2019 infection: a case report

BackgroundSARS-CoV-19 infection is associated with an increased risk of thrombotic events. We present a case of acute middle cerebral artery ischemic stroke in a patient with SARS-CoV-19 infection despite being on warfarin with supratherapeutic INR (International Normalized Ratio).Case presentationA 68-year-old Caucasian female with multiple comorbidities was admitted to the hospital with symptoms of upper respiratory tract infection. A rapid antigen test confirmed the diagnosis of COVID-19 pneumonia, and intravenous remdesivir was initiated. On the fifth day of admission, the patient experienced sudden onset confusion, slurred speech, left-sided hemiplegia, right-sided eye deviation, and left-sided facial droop. Imaging studies revealed an occlusion of the distal anterior M2 segment of the right middle cerebral artery, and an MRI of the brain confirmed an acute right MCA infarction. Notably, the patient was receiving warfarin therapy with a supratherapeutic INR of 3.2.ConclusionsThis case report highlights the potential for thromboembolic events, including stroke, in patients with COVID-19 infection, even when receiving therapeutic anticoagulation therapy. Healthcare providers should be vigilant for signs of thrombosis in COVID-19 patients, particularly those with pre-existing risk factors. Further research is necessary to understand the pathophysiology and optimal management of thrombotic complications in COVID-19 patients.

Neurosarcoidosis Complicated by Systemic Vasculitis (P9-5.005)

<h3>Objective:</h3> To describe a rare case of a patient with neurosarcoidosis complicated by systemic vasculitis of medium-large vessels. <h3>Background:</h3> Sarcoidosis is an inflammatory systemic disease characterized by the presence of noncaseating granulomas in any organ, when it affects the nervous system is called neurosarcoidosis. Systemic vasculitis is an unusual complication of sarcoidosis but it has not been previously reported in neurosarcoidosis. <h3>Design/Methods:</h3> N/A <h3>Results:</h3> A 62-year-old woman with a past medical history of hypertension, diabetes mellitus, coronary artery disease, neurosarcoidosis, s/p craniotomy (right cavernous sinus mass resection) was transferred to the hospital due to worsening headaches, generalized weakness, vomiting, and decreased oral intake for the last two weeks. On admission repeat brain MRI showed interval worsening of the known inflammatory right cavernous noncaseating granuloma, now extending into the right tentorial leaflet, right middle cranial fossa, and pituitary region, repeat vasculitis panel was negative, the patient was started on IV steroids and mycophenolate. However, the hospital stay was complicated by a syncopal episode, CT Head was normal but EKG showed a new T wave inversion with troponin elevation. Later on, the patient had worsening mentation and left-sided hemiparesis, CT head showed acute hypodensity in the right MCA territory and CTA showed bilateral stenosis of the distal right M1 and left M1segments of the MCAs, the patient was out of the window for tPA and was not a candidate for mechanical thrombectomy, she was started on aspirin. TTE and TEE did not show any intracardiac shunting/thrombi. Later on, she developed signs of ischemia in her right 1st and 2nd toes, aortogram showed partial and complete obstructions of both superficial femoral, anterior tibial, and peroneal arteries, and vascular surgery performed RLE SFA stent placement and recommended clopidogrel. IV cyclophosphamide was added with no further thromboembolic events. <h3>Conclusions:</h3> Vasculitis although uncommon can also occur in patients with neurosarcoidosis. <b>Disclosure:</b> Dr. Carvajal- Gonzalez has nothing to disclose. Dr. Arevalo has nothing to disclose. Dr. Chernyshev has nothing to disclose.

Spatial CT perfusion data helpful in automatically locating vessel occlusions for acute ischemic stroke patients.

Locating a vessel occlusion is important for clinical decision support in stroke healthcare. The advent of endovascular thrombectomy beyond proximal large vessel occlusions spurs alternative approaches to locate vessel occlusions. We explore whether CT perfusion (CTP) data can help to automatically locate vessel occlusions. We composed an atlas with the downstream regions of particular vessel segments. Occlusion of these segments should result in the hypoperfusion of the corresponding downstream region. We differentiated between seven-vessel occlusion locations (ICA, proximal M1, distal M1, M2, M3, ACA, and posterior circulation). We included 596 patients from the DUtch acute STroke (DUST) multicenter study. Each patient CTP data set was processed with perfusion software to determine the hypoperfused region. The downstream region with the highest overlap with the hypoperfused region was considered to indicate the vessel occlusion location. We assessed the indications from CTP against expert annotations from CTA. Our atlas-based model had a mean accuracy of 86% and could achieve substantial agreement with the annotations from CTA according to Cohen's kappa coefficient (up to 0.68). In particular, anterior large vessel occlusions and occlusions in the posterior circulation could be located with an accuracy of 80 and 92%, respectively. The spatial layout of the hypoperfused region can help to automatically indicate the vessel occlusion location for acute ischemic stroke patients. However, variations in vessel architecture between patients seemed to limit the capacity of CTP data to distinguish between vessel occlusion locations more accurately.

Abstract Number ‐ 227: Retrograde embolism from a Subclavian Thrombus causing Acute Ischemic Stroke in the Middle Cerebral Artery

Introduction Intracranial embolism to the middle cerebral artery usually occurs because of embolization from the heart, carotid artery or the aorta. Here we describe a case of a subclavian thrombus, embolizing to the middle cerebral artery. Retrograde embolism is a rarely described mechanism of acute ischemic stroke. Methods A 49‐year‐old gentleman with a history of hyperlipidemia, peripheral artery disease, smoking, prior stroke, previously treated arteriovenous malformation (AVM) in the left parieto‐occipital region and active methamphetamine use presented with sudden onset dysarthria and left facial weakness (NIH stroke scale–3). CT angiogram (CTA) head and neck demonstrated a right M2 inferior division occlusion and noted nonocclusive thrombus attached to right subclavian artery atherosclerotic plaque, proximal to the origin of the right vertebral artery and otherwise minimal extracranial, and intracranial atherosclerotic disease. He was not a candidate for IV thrombolysis due to his AVM, or mechanical thrombectomy (MT) due to low NIHSS. Apixaban was started. Trans‐esophageal echocardiogram (TEE) demonstrated a grade 2 PFO. Venous doppler ultrasound performed of his upper and lower extremities was negative. On day 2 of hospitalization, his left hemiparesis and dysarthria worsened. Repeat CTA head and neck showed absence of the right subclavian thrombus and new distal M1‐MCA thrombus, suggestive of retrograde embolism from the right subclavian artery. The patient was started on IV heparin and aspirin. A stroke in young work‐up was sent including antinuclear antibodies (ANA), antineutrophil cytoplasmic antibodies (ANCA), homocysteine, hexagonal phase phospho proteins, antiphospholipid antibodies, HIV, rheumatoid factor, cryoglobulin, hepatitis B antibodies, hepatitis C antibodies, sickle cell screen, Sjogren’s syndrome antibodies, drug screen, and was negative. Results Embolism (cardioembolism and artery–artery embolism) to the intracranial vasculature is an important cause of acute ischemic stroke. Retrograde embolization is rarely described as a cause of ischemic stroke. Our patient presented initially with distal right M2 occlusion and subocclusive thrombus of the right subclavian artery, associated with focal atherosclerosis but otherwise patent extracranial and intracranial cerebral vessels. Work‐up including transesophageal echocardiogram, and hypercoagulable work‐up was unrevealing. Repeat CT angiogram obtained in view of worsening deficits revealed absence of his right subclavian thrombus and new distal M1‐MCA occlusion presumed retrograde embolism from the right subclavian artery. This is may represent the consequence of local turbulence and retrograde flow during diastole. Conclusions When considering sources of embolic stroke, retrograde embolism should be considered in patients with focal atherosclerosis.

Abstract TMP68: Core/perfusion Mismatch In Acute Ischemic Stroke With M2 Occlusion: Prevalence And Associated Factors.

Background: The benefit of mechanical thrombectomy (MT) in acute ischemic stroke (AIS) patients with M2 occlusion is uncertain. Observational studies suggest that perfusion imaging may help select optimal M2 candidates for MT. We aimed to study the prevalence and factors associated with core/perfusion mismatch, as assessed by both CT and MRI, in an unselected population of AIS with M2 occlusion. Methods: Retrospective observational study including AIS patients with M2 occlusion and baseline perfusion imaging (MRI or CT) performed within 24hrs from last seen well. To avoid selection bias, patients were selected from the prospective registries of 3 centers with systematic use of perfusion imaging, including both MT-treated and untreated patients. Core/perfusion mismatch was defined as mismatch ratio (Tmax&gt;6s/ core volume) &gt;1.8 and mismatch volume (Tmax&gt;6s - core volume) &gt;15mL. Results: Overall, 156 and 196 patients were included in the MRI and CT cohorts, respectively. Last-seen-well to imaging time was 5.6hrs (IQR 3.9-9.7) and 3.5hrs (1.5-9.8) in the MRI and CT cohorts, and 103/156 (66%) and 134/196 (68%) had proximal M2 occlusions (the remainder had distal M2 occlusions). Median ASPECT score was 7 (5-8) and 8 (7-9), and core/perfusion mismatch was present in 70/156 (45%) and 167/196 (85%) patients. In both cohorts, mismatch was less frequent in distal M2 occlusions and among patients with lower ASPECTS (Figure). Multivariable analysis showed higher ASPECT scores (OR=3.09, 95%CI=2.11-4.52, P &lt;0.001 and OR=2.41, 95%CI 1.63-3.58, P &lt;0.001 in the MRI and CT cohorts) and proximal M2 occlusion (with distal M2 as a reference: OR=3.94, 95%CI=1.68-9.26, P =0.002 and OR=32.78, 95%CI 8.36-128.47, P &lt;0.001 in the MRI and CT cohorts) were independently associated with core/perfusion mismatch. Conclusion: Perfusion imaging may be useful in triaging M2 patients, particularly for those with ASPECT score &lt;8 and distal M2 occlusions. This has implication for trials.

Abstract 92: Tenecteplase Treatment And Thrombus Characteristics Associated With Early Reperfusion - An EXTEND-IA TNK Trials Analysis

Background: Intracranial occlusion site, contrast permeability, and clot burden are thrombus characteristics that influence alteplase-associated reperfusion. In this study, we assessed the reperfusion efficacy of tenecteplase and alteplase in subgroups based on these characteristics in a pooled analysis of the EXTEND-IA TNK trials. Methods: Patients with large vessel occlusion (LVO) were randomized to treatment with tenecteplase (0.25mg/kg or 0.4mg/kg) or alteplase (0.9mg/kg) prior to thrombectomy. The primary outcome, early reperfusion, was defined as the absence of retrievable thrombus or &gt;50% reperfusion on initial angiographic assessment. We compared the treatment effect of tenecteplase versus alteplase overall, and in subgroups based on intracranial occlusion site, the presence of contrast permeability (measured via residual flow grades), and clot burden (measured via clot burden scores), whilst adjusting for relevant covariates using mixed effects logistic regression models. Results: Among the 465 patients in the primary analysis, early reperfusion occurred in 18% (84/465). Tenecteplase was associated with a higher odds of early reperfusion (tenecteplase: 75/369 [20%] vs. alteplase: 9/96 [9%], aOR: 2.18 [95%CI: 1.03-4.63]). The difference between thrombolytics was most notable in distal M1 or M2 occlusions (tenecteplase: 53/176 [30%] vs. alteplase: 4/42 [10%], aOR: 3.73 [95%CI: 1.25-11.11]), thrombi with contrast permeability (tenecteplase: 38/160 [24%] vs. alteplase: 5/48 [10%], aOR: 2.83 [95%CI: 1.00-8.05]), and in low clot burden occlusions (tenecteplase: 66/261 [25%] vs. alteplase: 5/67 [7%], aOR: 3.93 [95%CI: 1.50-10.33]). Both thrombolytics had limited early reperfusion efficacy in proximal occlusions (ICA: tenecteplase 1/73 [1%] vs. alteplase 1/19 [5%]) and in high clot burden occlusions (tenecteplase: 9/108 [8%] vs. alteplase: 4/29 [14%], aOR: 0.58 [95%CI: 0.16-2.06]). Conclusions: Tenecteplase demonstrates superior early reperfusion versus alteplase in distal LVO, in contrast-permeable thrombi, and in lesions with low clot burden. Reperfusion efficacy remains limited in ICA occlusions and lesions with high clot burden. Further improvements in intravenous thrombolytics are required.

Complete recanalization predicts favorable outcome in patients with distal M2-M3 middle cerebral artery occlusions following endovascular thrombectomy

Background— scanty articles illustrate the prognostic factors for favorable outcome after endovascular thrombectomy (EVT) in distal vessel occlusion (DMVO). Moreover, the current literature is diversified; conglomerating both primary, secondary, and anterior, posterior circulations embolic strokes in the same shell. Purposeto identify the association between complete reperfusion and favorable outcome following EVT for DMVO in the middle cerebral artery (MCA) territory. Methods—we performed a retrospective analysis of prospectively maintained EVT registries at two comprehensive stroke centers between January 2015 and December 2019 for consecutive stroke patients with MCA-DMVO. DMVO was defined as an occlusion of distal M2 and M3 segments of the MCA. Only patients with primary isolated occlusions were included. A multivariate logistic regression was utilized to identify clinical and procedural-related factors associated with the 90-day favorable clinical outcome [defined as modified Rankin score (mRS) 0-2] after EVT. Results—Out of 1823 within the registries; 66 patients (median age was 72 (60-78) and 59% were males) with primary isolated DMVO of the MCA were eligible for inclusion in the current study. Complete reperfusion was achieved in 56% (37/66) of the patients with no difference among the reperfusion strategies while the favorable outcome was observed in 68% (45/66). In the multivariate analysis, final complete reperfusion [modified Thrombolysis In Cerebral Infarction (mTICI) score 2c-3] was significantly associated with favorable outcome [aOR=7.69; (95% CI 1.73-34.17); p=.01], while higher baseline NIHSS score [aOR=0.82; (95% CI 0.69-0.98); p=.03] and increased imaging to puncture interval [aOR=0.99; (95% CI 0.98, 1.00); p=.01] decreased the probability of the favorable outcome. Conclusionaccording to our results, complete reperfusion was the most significant predictor of the favorable outcome, while higher baseline NIHSS and longer imaging to puncture interval decreased the probability of the favorable outcome.

Predictors and Impact of Sulcal SAH after Mechanical Thrombectomy in Patients with Isolated M2 Occlusion.

Data on SAH after M2 mechanical thrombectomy are limited. We aimed to determine the prevalence of sulcal SAH after mechanical thrombectomy for M2 occlusion, its associated predictors, and the resulting clinical outcome. The study retrospectively reviewed the data of patients with acute ischemic stroke who underwent mechanical thrombectomy for isolated M2 occlusion. The patients were divided into 2 groups according to the presence of sulcal SAH after M2 mechanical thrombectomy. Angiographic and clinical outcomes were compared. Multivariable analysis was performed to identify independent predictors of sulcal SAH and unfavorable outcome (90-day mRS, 3-6). Of the 209 enrolled patients, sulcal SAH was observed in 33 (15.8%) patients. The sulcal SAH group showed a higher rate of distal M2 occlusion (69.7% versus 22.7%), a higher of rate of superior division occlusion (63.6% versus 43.8%), and a higher M2 angulation (median, 128° versus 106°) than the non-sulcal SAH group. Of the 33 sulcal SAH cases, 23 (66.7%) were covert without visible intraprocedural contrast extravasation. Distal M2 occlusion (OR, 12.04; 95% CI, 4.56-35.67; P < .001), superior division (OR, 3.83; 95% CI, 1.43-11.26; P = .010), M2 angulation (OR, 1.02; 95% CI, 1.01-1.04; P < .001), and the number of passes (OR, 1.58; 95% CI, 1.22-2.09; P < .001) were independent predictors of sulcal SAH. However, covert sulcal SAH was not associated with an unfavorable outcome (P = .830). After mechanical thrombectomy for M2 occlusion, sulcal SAH was not uncommon and occurred more frequently with distal M2 occlusion, superior division, acute M2 angulation, and multiple thrombectomy passes (≥3). The impact of covert sulcal SAH was mostly benign and was not associated with an unfavorable outcome.

Effects of endovascular therapy for mild stroke due to proximal or M2 occlusions: meta-analysis

ObjectiveTo conduct a meta-analysis to evaluate the effect of endovascular therapy (EVT) in mild acute ischemic stroke (AIS) due to proximal versus distal occlusions.MethodsWe searched PubMed, Embase, the Cochrane Library,...

Early Exposure of the Dorsal Surface of M1 Segment via the Distal Transsylvian Approach for Clipping of Anteroinferior-Projecting Middle Cerebral Artery Bifurcation Aneurysms.

Background Middle cerebral artery bifurcation (MCAB) aneurysms are common intracranial aneurysms. Anteroinferior-projecting MCAB aneurysms, with M1 segment usually embedded into the deep part of the Sylvian fissure, cause some surgical challenges. The distal transsylvian approach (DTSA) allows M1 exposure from the dorsal surface for proximal control in the early step. Therefore, this study aimed to demonstrate the efficacy and safety of DTSA for clipping anteroinferior-projecting MCAB aneurysms. Methods Among 97 patients with MCA aneurysms, 13 with anteroinferior-projecting MCAB aneurysms who underwent aneurysm clipping via the DTSA between June 2018 and January 2021 were retrospectively evaluated for the aneurysm obliteration rate, surgical complications, and outcomes. Results Ten patients (76.9%) had ruptured MCAB aneurysms and three (23.1%) had incidentally discovered unruptured MCAB aneurysms. Favorable outcome was achieved in 100% of patients with good grade. The complete aneurysm obliteration rate was 100% without intraoperative lenticulostriate artery injury. Twelve (92.3%) patients had early identified distal M1 segment for proximal control, and one (7.7%) patient had premature rupture of aneurysm that achieved favorable outcome at 3 months postoperatively. Difficult M1 exposure and premature rupture occurred in the patient with MCAB located above the Sylvian fissure line. Permanent postoperative neurological deficit was detected in one patient due to severe vasospasm. Conclusion DTSA, which simplify the early exposure of the dorsal surface of distal M1, is safe and effective for clipping anteroinferior-projecting MCAB aneurysms without extensive Sylvian fissure dissection. High-positioned MCAB requires careful dissection of the aneurysm neck with consideration of tentative clipping preparation.

Artificial intelligence software for diagnosing intracranial arterial occlusion in patients with acute ischemic stroke.

To evaluate the diagnostic performance of AI software in diagnosing intracranial arterial occlusions in the proximal anterior circulation at CT angiography (CTA) and to compare it to manual reading performed in clinical practice. Patients with acute ischemic stroke underwent CTA to detect arterial occlusion in the proximal anterior circulation. Retrospective review of CTA scans by two neuroradiologists served as reference standard. Sensitivity and specificity of AI software (StrokeViewer) were compared to those of manual reading using the McNemar test. The proportions of correctly detected occlusions in the distal internal carotid artery and/or M1 segment of the middle cerebral artery (large vessel occlusion [LVO]) and in the M2 segment of the middle cerebral artery (medium vessel occlusion [MeVO]) were calculated. Of the 474 patients, 75 (15.8%) had an arterial occlusion in the proximal anterior circulation according to the reference standard. Sensitivity of StrokeViewer software was not significantly different compared to that of manual reading (77.3% vs. 78.7%, P = 1.000). Specificity of StrokeViewer software was significantly lower than that of manual reading (88.5% vs. 100%, P < 0.001). StrokeViewer software correctly identified 40 of 42 LVOs (95.2%) and 18 of 33 MeVOs (54.5%). StrokeViewer software detected 8 of 16 (50%) intracranial arterial occlusions which were missed by manual reading. The current AI software detected intracranial arterial occlusion with moderate sensitivity and fairly high specificity. The AI software may detect additional occlusions which are missed by manual reading. As such, the use of AI software may be of value in clinical stroke care.

Abstract WP160: First-Pass Effect Modification In Proximal Vs Distal M1 Occlusion Thrombectomy

Modified first pass effect (mFPE) of TICI 2B or greater is an independent predictor of clinical outcome in patients who undergo mechanical thrombectomy (MT). Location of the occlusion in the M1 segment may affect the mFPE and may influence clinical outcomes. A comparison of mFPE between occlusions of the proximal and distal (sparing lenticulostriate branches) M1 segments of the MCA has yet to be performed. We aim to examine the interaction between first pass effect and clinical outcomes in proximal versus distal M1 occlusions. We performed retrospective analysis of patients who underwent MT between 2014 and 2020. Patients were included if they were treated for M1 occlusion within 24 hours from last seen normal, and achieved successful recanalization (TICI2b or greater). Patients were excluded if they were not successfully recanalized, or if they had other intracranial or multifocal occlusions. A total of 264 patients were included in this analysis. Ninety two patients had proximal M1 occlusions and 172 had distal M1 occlusions. Patients with proximal M1 occlusions had higher NIHSS (median 18 vs. 16, p=0.003), lower ASPECTS (mean 8.5 vs 9, p=0.02), and were less likely to be females (44.6% vs. 62.8%, p=0.006). Modified first pass effect was achieved in 45.3% of distal M1 occlusions compared to 31.9% of proximal (p=0.047). Excellent clinical outcome, defined as mRS of 0-1 at 90 days was higher in distal occlusion group (38.8% vs. 24.7%, p=0.03). Additionally, the proximal occlusion group was more likely to experience any grade of hemorrhagic transformation (HT) (37.4 vs. 23.3, p=0.02). Other baseline characteristics and time metrics did not differ between the two groups. In a multivariate analysis of predictors of excellent outcome in the overall cohort, ASPECTS (OR=1.39, p = 0.026) and proximal occlusion site (OR=0.485, p=0.037) were the only two independent predictors. Therefore, mFPE was not a predictor of excellent outcome when adjusted for exact location of occlusion.

Cost-effectiveness of thrombectomy in patients with minor stroke and large vessel occlusion: effect of thrombus location on cost-effectiveness and outcomes

BackgroundTo evaluate the cost-effectiveness of endovascular thrombectomy (EVT) to treat large vessel occlusion (LVO) in patients with acute, minor stroke (National Institute of Health Stroke Scale (NIHSS) <6) and impact...

Endovascular Thrombectomy for Distal Medium Vessel Occlusions of the Middle Cerebral Artery: A Safe and Effective Procedure

Distal medium vessel occlusions (DMVOs) are increasingly recognized as a next target for endovascular thrombectomy (EVT). Our objective was to investigate safety and clinical outcomes of EVT for DMVO of the middle cerebral artery (MCA). We analyzed data of the Lille Reperfusion Registry from January 2017 to September 2020. Patients with a primary or secondary DMVO of the MCA seen on pretreatment angiogram were included. Only patients with a eTICI score 2b50-2b67 on initial angiogram were considered. Baseline characteristics, angiographic clinical, and safety outcomes were compared between patientstreated with EVT or standard medical treatment (no-EVT). Of the 171 patients included, 96 received EVT (46.9% male, 68.7 ± 15.8 years) and 75 received standard medical treatment (44% male, 73.9 ± 13.1 years). EVT patientshad a better improvement of the NIHSS score atdischarge (adjusted mean difference: 3.71; 95% CI: 1.18-6.24). In the distal M2 occlusions subgroup, EVT was significantly associated with a higher rate of early neurologic improvement (adjusted OR: 3.62 95% CI: 1.31-10.03), NIHSS improvement at discharge (adjusted mean difference: 5.23; 95% CI: 2.18-8.29), and improved modified Rankin Scale score at 3 months (adjusted common OR for 1 point improvement: 3.06; 95% CI: 1.30 to 7.23). Symptomatic intracranial hemorrhage occurred in 3.1% in the EVT group and in 9.5% in the no-EVT group. EVT for DMVO of the MCA appears to be safe and may lead to improved clinical outcomes. This effect was especially pronounced in patients with distal M2 occlusions, warranting randomized trials to validate this result.

A Case Report: A 37 Years-old Women with Takayasu Arteritis

Background: A rarity of form of vasculitis, also known as TAK, induces inflammation in the walls of the major arteries in the body: the aorta and its main branches. The disease results from a body attack and inflammation of the walls of the arteries caused by the body's own immune system.&#x0D; Case Presentation: A 37-years-old women had complaints of fever, giddiness, weakness of right upper limb and lower limb since1 day. After undergoing whole blood count, liver function examination, renal and MRI function checks, CT scan, angiography, etc. was studied. She was diagnosed with takayasu arteritis. She had past medical history of neck pain and numbness since January 2020. For these complaints her family members referred her in private hospital. There is no significant history of surgery in present, lower segment caesarean section and piles operation was done previously. Physical findings were normal except the Glasgow Coma Scale score was 11 that is, patient was semi-conscious, In General appearance patient activity was dull and weak due disease condition, Patient’s all routine investigations were normal except few like Total WBC count was increased (21,500cell /cm) due to increased infection, Granulocytes were increased that is 75 % due to infection and autoimmune disease, ESR was increased that is52mm/h. Angiography showed block in the right common carotid artery, MRI- showed Acute infract in left fronto temporo parietal region involving insular par ventricular white matter, absent flow in distal M1 segment of MCA.&#x0D; Conclusion: The most frequently involved arteries and the angiographic trends in this Takayasu Arteritis study were subclavian arteries and carotid arteries. The difference between angiographic characteristics may lead to clinical differences. Operations and surgery should be carried out at various points in the course of the disease.

Early Exposure of the Dorsal Surface of M1 Segment via the Distal Transsylvian Approach for Clipping of Anteroinferior-Projecting Middle Cerebral Artery Bifurcation Aneurysms.

Background:Middle cerebral artery bifurcation (MCAB) aneurysms are common intracranial aneurysms. Anteroinferior-projecting MCAB aneurysms, with the M1 segment usually embedded into the deep part of the Sylvian fissure, cause some surgical challenges. The distal transsylvian approach (DTSA) allows M1 exposure from the dorsal surface for proximal control in the early step. Therefore, this study aimed to demonstrate the efficacy and safety of DTSA for clipping anteroinferior-projecting MCAB aneurysms.Materials and Methods:Among 97 patients with MCA aneurysms, 13 with anteroinferior-projecting MCAB aneurysms who underwent aneurysm clipping via the DTSA between June 2018 and January 2021 were retrospectively evaluated for the aneurysm obliteration rate, surgical complications, and outcomes.Results:Ten patients (76.9%) had ruptured MCAB aneurysms and three (23.1%) had incidentally discovered unruptured MCAB aneurysms. Favorable outcome was achieved in 100% of patients with good grade. The complete aneurysm obliteration rate was 100% without intraoperative lenticulostriate artery injury. Twelve (92.3%) patients had early identified distal M1 segment for proximal control, and one (7.7%) patient had premature rupture of aneurysm that achieved favorable outcome at 3 months postoperatively. Difficult M1 exposure and premature rupture occurred in the patient with MCAB located above the Sylvian fissure line. Permanent postoperative neurological deficit was detected in one patient due to severe vasospasm.Conclusions:DTSA, which simplify the early exposure of the dorsal surface of distal M1, is safe and effective for clipping anteroinferior-projecting MCAB aneurysms without extensive Sylvian fissure dissection. High-positioned MCAB requires careful dissection of the aneurysm neck with consideration of tentative clipping preparation.

Abstract 1122‐000005: Plasminogen Activator Inhibitor‐1 5G/5G Polymorphism – Do We Know All About It?

Introduction : The etiology of ischemic stroke is heterogeneous, and it has been proposed that different stroke subtypes might have different genetic architecture 1,2. The plasminogen activator inhibitor‐1 (PAI‐1) has been of particular interest due to its role in thrombotic diseases. Several polymorphisms have been found for this gene, with some having protective effect while others increase the risk of ischemic and hemorrhagic strokes 3,4. The protective role appears to be due to the role of PAI‐1 in fibrinolytic cascade and that PAI‐1 also inhibit plasmin‐dependent metalloproteinases activation. We hereby, present a case of ischemic stroke in young adult and its association with our gene of interest. Methods : Case: We present a case of 43‐year‐old woman with past medical history significant for Acetylcholine Receptor (AChR) antibody positive Myasthenia Gravis diagnosed in 1993 status post thymectomy (1994), currently on prednisone and intravenous immunoglobulin every two weeks (failed cyclosporine and mycophenolate mofetil). She had two events in 2018 where she reported episodic right sided numbness and weakness that lasted for few hours. Stroke workup was done, and she was found to have focal moderate to severe stenosis of the left middle cerebral artery (MCA) on CT angiography (figure 1) with very subtle left hypoperfusion in the MCA on the brain single‐photon emission computerized tomography scan. She underwent catheter angiogram (figure 1) showing severe stenosis involving the mid and distal M1 segment of the left MCA and nondominant proximal A1 segment left anterior cerebral artery (ACA). There were robust leptomeningeal collaterals from the left anterior and left posterior cerebral arteries. She also reported history of two miscarriages in the first trimester. Hypercoagulable workup was done and all of those were negative including: SLE profile, Lupus anticoagulant, ANA comprehensive panel, Cryoglobulin, Anticardiolipin antibody, Antithrombin III, Antithrombin antigen, protein C, protein S, Factor VIII activity, Factor V Leiden. She also had rheumatoid arthritis factor, Homocysteine, sedimentation rate, and C‐reactive protein done which were unremarkable. Genetic workup showed that she is PAI‐1 5G/5G homozygous. She has been stable since 2018 without new focal neurological events and is on Aspirin monotherapy and Statin. Results : The genetics for stroke disease are very complicated and yet to be discovered fully. The association between PA‐1 5G/5G and intracranial stenosis has not been reported previously. New genetic associations will need to be increasingly considered as we assess our cerebrovascular diseases and stroke patients Conclusions : • With the current knowledge, ischemic stroke have polygenic basis but no single common “stroke gene” has been identified yet. • Here we present a case suggesting that PAI‐1 5G/5G genotype is may be associated with an independent risk of intracranial atherosclerosis.