Large Vessel Acute Stroke Research Articles

Clinical Manifestations.

Individuals diagnosed with mild cognitive impairment and dementia (MCI/Dem) are excluded from research on intervention for acute ischemic stroke; This research gap places stroke physicians worldwide in dilemmas while treating patients with cognitive decline. One example is acute stroke of large brain arteries, typically manifesting as immediate onset of severe neurological disability. Endovascular treatment (EVT), aka catheter-base clot removal, is considered the gold-standard treatment and when applied within hours after onset, can mitigate or reverse deficits and dramatically improve outcomes. Our goal was to evaluate efficacy and safety of EVT for acute stroke in MCI/Dem. This is a single site retrospective study from Rabin Medical Center,2019-2021. Inclusion criteria was new onset acute large vessel stroke receiving EVT treatment, ages 18-85 years. Pre-stroke cognitive status was assessed using previous diagnosis, assessments in geriatric / occupational therapy clinics, nurse functional questionnaire and rehabilitation interview. Individuals were dichotomized to MCI/Dem (any severity) and unimpaired via consensus between two behavioural neurologists. The MCI/Dem group was matched to unimpaired individuals for sex, age, pre-stroke functional independence, and stroke arterial territory, severity and time to EVT. The outcomes were retrospectively assessed 90 days after stroke and included mortality, intracranial haemorrhage, and pre to post stroke difference in the modified Rankin scale (mRS), commonly used instrument for stroke functional independence. We identified 306 individuals with acute large vessel stroke who underwent EVT, of which 32 with pre-stroke MCI/Dem. After matching, we saw no differences between non impaired group to MCI/Dem group in functional outcome measured by mRS change, (56% vs.53%, p = 0.8), brain hemorrhage(22% vs. 9%, p = 0.68) and mortality (25% vs. 12%,p = 0.2). To our knowledge this is the first study to report on EVT outcomes in individuals with MCI/Dem. Our results suggest interventions for acute large vessel stroke may have similar efficacy and safety profile in individuals with pre-stroke MCI/Dementia and thus challenge previous recommendations to exclude them from therapy. Our data is retrospective and thus of inadequate design to suggest change to clinical guidelines. Further research on stroke interventions in MCI/Dem is urgently needed to guide day-to-day clinical decision making.

Semi-automated mapping of occluded arterial segments in acute large vessel stroke from computed tomography angiography

Catheterisation of occluded artery is the most crucial step in the mechanical thrombectomy of large vessel occlusions. Being a blind procedure, potential major untoward events could be anticipated at this stage. In this study, we evaluated the feasibility of reconstruction of the occluded vascular segment from CT angiography, exploiting the attenuation difference between the clot and adjacent brain parenchyma. Twenty-five patients with large vessel occlusion who achieved TICI2B/3 recanalization were identified. The semi-automated reconstruction was done using an open-source 3D segmentation software by two observers. The generated arterial anatomy was categorized as congruent, if all the major arterial segments namely, internal carotid artery, M1 middle cerebral artery, bifurcation, and major divisions matched with post thrombectomy angiograms. The discrepancy of one or more than one arterial segment was classified as mild or total mismatch respectively. Congruent arterial mapping was possible in 88% and 92 % patients for observer 1 and observer 2 respectively, while mild mismatch was noted in two patients for both the observers. Mismatch mostly occurred in superior division for both observers(100% vs 66.6%). The interrater agreement was good (0.77) and the accuracy was not influenced by the length of the clot. The median time for reconstruction was 4 minutes for both the observers (p - 0.21). Delineation of the anatomy of the occluded major intracranial artery is possible and corresponds with the actual anatomy. It could be used as a guide during thrombectomy procedures.

Management and outcome of patients with acute ischemic stroke and tandem carotid occlusion in the ESCAPE-NA1 trial

BackgroundThe optimal treatment and prognosis for stroke patients with tandem cervical carotid occlusion are unclear. We analyzed outcomes and treatment strategies of tandem occlusion patients in the ESCAPE-NA1 trial.MethodsESCAPE-NA1 was...

Hyperbaric oxygen therapy after acute ischemic stroke with large penumbra: a case report

BackgroundHyperbaric oxygen therapy (HBOT) for the treatment of acute stroke has been under the radar for a long time. Previous studies have not been able to prove efficacy. Several factors might have contributed to such inconsistent results. The timing of delivering the hyperbaric oxygen in relation to the stage of stroke evolution may be an important factor. This was not taken into account in the previous studies as there was no feasible and standardized method to assess the penumbra in the acute phase. Now with the perfusion scan appearing as a key player in the acute stroke management, precise stroke patient selection for hyperbaric oxygen therapy deserves a second chance similar to mechanical thrombectomy.Case presentationA 62-year-old female patient who presented with acute large vessel stroke was not eligible for chemical or mechanical thrombectomy. There was a large penumbra on imaging. She got treated with several sessions of hyperbaric oxygen over a 2-week period immediately after stroke. The patient showed significant improvement on the follow-up perfusion imaging as well as some clinical improvement. The more impressive radiological improvement was probably due to the presence of relatively large core infarction at baseline affecting functional brain areas. The patient continued to improve clinically on her 6-month follow up visit.ConclusionOur case demonstrates immediate stroke-related penumbra improvement associated with HBOT. Based on that, we anticipate a potential role for HBOT in acute stroke management considering precise patient selection. Future randomized controlled trials are needed and should take that in consideration.

A Unique Signature of Cardiac-Induced Cranial Forces During Acute Large Vessel Stroke and Development of a Predictive Model.

Cranial accelerometry is used to detect cerebral vasospasm and concussion. We explored this technique in a cohort of code stroke patients to see whether a signature could be identified to aid in the diagnosis of large vessel occlusion (LVO) stroke. A military-grade three-axis accelerometer was affixed to a headset. Accelerometer and electrocardiogram (ECG) outputs were digitized at 1.6kHz. We call the resulting digitized signals the "headpulse." Three-minute recordings were performed immediately after computed tomography (CT) angiography (CTA) and/or immediately before and after attempted mechanical thrombectomy in patents with suspected stroke. The resulting waveforms were inspected by eye and then subjected to supervised machine learning (MATLAB Classification Learner R2018a) to train a model using fivefold cross-validation. Of 42 code stroke subjects with recordings, 19 (45%) had LVO and 23 (55%) had normal CTAs. In patients without LVO, ECG-triggered waveforms followed a self-similar time course revealing that the headpulse is highly coupled to the cardiac contraction. However, in most patients with LVO, headpulses showed little cardiac contraction correlation. We term this abnormality "chaos" and parameterized it with 156 measures of trace-by-trace variation from the ECG-signal-averaged mean for machine learning model training. Selecting the best model, using biometric data only, we properly classified 15/19 LVOs and 20/23 non-LVO patients, with receiver operating characteristic curve area = 0.79, sensitivity of 73%, and specificity of 87%, P < 0.0001. Headpulse waveforms following thrombectomy showed return of cardiac contraction correlation. Headpulse recordings performed on patients with suspected acute stroke significantly identify those with LVO. The lack of temporal correlation of the headpulse with cardiac contraction and resolution to normal may reflect changes in cerebral blood flow and may provide a useful technique to triage stroke patients for thrombectomy using a noninvasive device.

Intrathrombus polymer coating deposition: a pilot study of 91 patients undergoing endovascular therapy for acute large vessel stroke. Part I: Histologic frequency

BackgroundPolymer coating embolism due to vascular medical device use is an increasingly recognized iatrogenic complication. This phenomenon has been linked with various adverse effects including neuroinflammation, acute ischemic stroke, cerebral...

Abstract WP74: Right Hemispheric Infarcts Have Higher CT Perfusion Penumbra Volume for Given NIH Stroke Scale: Results From BEST Prospective Cohort Study

Introduction: Right hemispheric strokes have a higher average infarct volume than left hemisphere strokes for the same severity of NIH stroke scale (NIHSS). This phenomenon, although well documented by CT and MRI based volume calculation of final infarct volume, is yet to be confirmed with automated acute CT/MR perfusion imaging in acute large vessel stroke setting. Additionally, penumbral volumes have not been well studied with regard to laterality of stroke. Methods: Data from the BEST prospective cohort study, a multicenter study that enrolled consecutive patients with anterior cerebral large vessel occlusion undergoing endovascular treatment were used for analysis. We determined the correlation between baseline NIHSS and CTP penumbra volume (CTPp; total volume of Tmax&gt;6sec) as well as core infarct volume (CTPc) for right sided and left sided strokes. We also determined the difference in CTPp and CTPc between right and left sided stroke for every 5-point increase in the baseline NIHSS. Results: Of the 443 enrolled patients, 165 (82 female, median age 69 [IQR 57, 81]) had complete data for baseline CTPp and CTPc; one patient with bilateral strokes was excluded. Median CTPp for right sided (n=74) strokes was 127.5 cc [IQR 83, 167] and for left sided (n=90) strokes was 93.0 cc [IQR 62, 155]. Median CTPc for right sided strokes was 15.0 cc [IQR 0, 35] and that for left sided strokes was 6.5 cc [0, 24]. After adjusting for baseline NIHSS, right sided strokes had significantly higher CTPp than did left sided (p=0.001), but no evidence of laterality for CTPc was observed (p=0.09). The correlation coefficient for NIHSS and CTPp was 0.23 and 0.33, and that for CTPc was 0.16 and 0.19 for right and left side, respectively. Highest difference in CTPp between sides was observed at NIHSS 16-25 (table). Conclusions: Right hemispheric strokes have higher CTPp but not CTPc as compared to the left. For a given NIHSS, right hemispheric strokes may have larger salvageable tissue.

Abstract WMP113: Translational Evaluation of Acid/Base and Electrolyte Alterations in Acute Large Vessel Stroke

Background and Purpose: Monitoring for hypotension, hyperglycemia, hypoxia, and dehydration is key to reducing early death in stroke patients. Evaluation of physiological predictors of infarct volume and mortality may provide opportunities for effective interventions to improve outcomes. The purpose of this study is: 1) to describe and compare the predictive effects of venous blood gas (VBG) on infarct volume and mortality in acute stroke in rats; 2) and we have begun to collect arterial blood gas (ABG) to compare differences obtained proximal and distal to the occluded intracranial thrombi in acute ischemic stroke patients. Methods: 3-month old Sprague-Dawey rats (n = 9) underwent permanent or transient middle cerebral artery occlusion (MCAO). Pre- and post-MCAO venous samples provided pH, pCO 2 , pO 2 , and electrolyte values (iCa 2+ , K + , and Na + ). Linear regression determined predictors of infarct volume from these values, and Cox regression analyzed VBG changes between tMCAO (n = 28) and pMCAO (n = 29) to determine predictors of mortality. We compared mean proximal and distal pH, pCO 2 , pO 2 , and electrolytes (iCa 2+ , K + , and Na + ) in stroke patients (n = 7) arterial samples using Wilcoxon Signed Ranks test. Results: Animal studies demonstrated pH and iCa 2+ are predictors of infarct volume, but not mortality. After pMCAO (n = 9), change in pH or iCa 2+ significantly predicted infarct volume [F(1,7) = 7.351, β = -0.716, p = 0.03] and [F(1, 7) = 6.782, β = -0.701, p = 0.035]; as pH and calcium decreased, infarct volume increased. These variables explained 44% and 42% of the total variance in these models. In human patients (n = 7), there were significant differences in blood samples proximal and distal to the intracranial thrombus for pCO 2 (p = 0.018), HCO 3- (p = 0.028), iCa 2+ (p = 0.043), K + (p = 0.028), and Na + (p = 0.044). Conclusions: In conclusion, there are acute changes in acid/base balance and electrolytes during stroke in rodent models and humans. In cross-species comparison ionized calcium changes were significant in both, with iCa 2+ changes predicting stroke volume in the rat model. These preliminary findings are novel, and warrant further exploration in human patients.

First-Line Contact Aspiration vs. Stent Retriever for Acute Large-Vessel Ischemic Stroke

Most patients in recent mechanical thrombectomy trials were treated with stent retrievers. But the large-bore catheter that is required to deploy a

Abstract WP392: The Experiences of Young Adult Stroke Survivors Who Go Directly Home From Acute Care

Introduction: Young adults are the fastest growing population of stroke patients. Current treatments enable physicians to reverse ischemic stroke, and young adult stroke survivors (YASS) are increasingly discharged directly home with few to no neurological deficits. Without acute rehabilitation needs, there are limited opportunities to identify and address the psychosocial issues that may result from this significant health event. The purpose of this study was to explore the experiences of YASS who went home from acute care with few to no neurological deficits. Method: Qualitative research methods were used. YASS &lt;55 years who received intravenous/intra-arterial treatment for a large vessel acute stroke and discharged directly home from a metropolitan hospital were recruited. Participants were interviewed in person using in-depth, semi-structured one hour interviews. They were asked about post-stroke discharge experiences and what it is like to be a YASS. Interviews were audio-recorded, transcribed verbatim by the interviewer and analyzed with a level one summary to discern themes. Results: Three YASS, one female and two males, age 34-55 years and 3-7 years post-stroke participated. Analysis of the data identified six overarching themes: stress as a precursor to stroke, experiencing invisible symptoms, fear and anxiety of future stroke, emotional responses, no personal frame of reference for the event, and sources of strength to recover. Discussion: YASS that did exceptionally well following a treated stroke still experienced emotional and cognitive changes. All participants spoke of experiencing high levels of life stress preceding their strokes which they perceived as a “hidden” risk factor. They felt their outward appearances and functional levels were incongruent with inner symptoms of feeling “not themselves”. They expressed fear and anxiety of having another stroke. Perceptions of their experiences were based on their healthcare providers that used positive expressions for their outcomes (i.e. “lucky” and “miraculous”). The YASS talked about family support and faith that helped recovery. Conclusion: Further research is needed to explore this emerging population of YASS to take steps toward optimizing their experiences and recovery.

Advances in minimally invasive treatment of hemorrhagic and ischemic stroke.

Advances in minimally invasive treatment of hemorrhagic and ischemic stroke.

Differences in Factors Predicting Outcome and Mortality after Mechanical Thrombectomy for Acute Large Vessel Stroke Between Patients over and Under 70 Years of Age: A Five Year Retrospective Study

Differences in Factors Predicting Outcome and Mortality after Mechanical Thrombectomy for Acute Large Vessel Stroke Between Patients over and Under 70 Years of Age: A Five Year Retrospective Study

Complex interventional treatment in a patient with atrial fibrillation and stroke caused by large carotid artery thrombus: a case report

BackgroundThe treatment option for acute ischaemic stroke depends on the duration of symptoms, the dynamics of neurological condition changes, the aetiology, type of stroke, as well as the results of angiographic and neuroimaging tests.Case presentationA 60-year-old male patient presented with progressive left hemisphere stroke caused by extensive cardiogenic embolism of the common carotid artery and a thrombus closing the internal carotid artery from its ostium to the level of its intracranial division. The complex revascularisation therapy involving surgical embolectomy of the common carotid artery, thrombectomy of the internal carotid artery and intra-arterial thrombolysis has led to the improvement of arterial patency and has countered the progression of acute cerebral ischaemia.ConclusionEmergency carotid embolectomy together with thrombectomy and local thrombolytic rt-PA treatment may be a reasonable rescue therapy for carefully selected patients with large-vessel acute stroke. Further research is needed to establish the advantages and safety of surgical thrombectomy in patients with acute embolic occlusion of the carotid artery and ineffectiveness of or contraindications for systemic thrombolytic treatment.

Abstract W MP16: Introducing the Imaging the Collaterals in Acute Stroke (iCAS) Multicenter MRI Trial

Introduction: imaging Collaterals in Acute Stroke (iCAS) is an NIH-funded, multicenter study to determine if non-contrast arterial spin label (ASL) MRI can characterize collateral flow in patients presenting with acute large vessel stroke and whether it can identify patients who benefit from endovascular therapy. It also enables direct comparison with current state-of-the-art clinical perfusion imaging, bolus perfusion-weighted imaging (PWI). Hypotheses: (1) ASL identifies collaterals with high sensitivity and specificity compared to digital subtraction angiography (DSA). (2) Increasing collateral grade determined by either ASL or DSA is associated with higher CBF. (3) ASL collateral grade independently predicts reduced infarct growth. (4) Patients with a “target mismatch” based on PWI(Tmax&gt;6) can be identified using ASL. (5) Only patients with intermediate grade collaterals will benefit from early reperfusion. Methods: 180 patients will be recruited from up to 6 sites over 5 yrs. Current sites include Stanford, Swedish Hospital Seattle, and UPMC. Inclusion criteria: &gt;18 yrs; NIHSS &gt;=5; planned endovascular therapy (primary or adjuvant therapy following IV tPA); planned MR imaging with ASL &amp; PWI; IA therapy &lt;60 min from MR completion and &lt;12 hrs of symptom onset. Exclusion criteria: mRS&gt;=2 prior to the qualifying stroke; Cr clearance &lt;40 ml/min; contrast allergy; pregnancy; MRI contraindications. MRI will be obtained at 3 time points (&lt;12 hrs, 18-36 hrs later, 5 d), with clinical data at 30 &amp; 90 days. Results: 7 patients have been recruited. While formal image analysis has not been performed, initial review suggests that ASL has similar performance to PWI in this patient population (Fig). Conclusion: It is feasible to acquire ASL during an acute stroke MRI workup, enabling comparison of both collateral measures with DSA and perfusion metrics with PWI. It will provide a framework to account for the crucial role of collaterals in endovascular triage strategy.

Quantitative T2'-mapping in acute ischemic stroke.

Quantitative T2'-mapping detects regional changes in the relation of oxygenated and deoxygenated haemoglobine and might reflect areas with increased oxygen extraction. T2'-mapping in conjunction with an elaborate algorithm for motion correction was performed in patients with acute large-vessel stroke, and quantitative T2'-values were determined within the diffusion-weighted imaging lesion and perfusion-restricted tissue. Eleven patients (median age, 71 years) with acute middle cerebral or internal carotid artery occlusion underwent MRI before scheduled endovascular treatment. MR-examination included diffusion- and perfusion-weighted imaging and quantitative, motion-corrected mapping of T2'. Time-to-peak maps were thresholded for different degrees of perfusion delays (eg, ≥0 s, ≥ 2s) when compared with a reference time-to-peak value from healthy contralateral tissue. Mean T2'-values in areas with reduced apparent diffusion coefficient and in areas with impaired perfusion were compared with T2'-values in corresponding contralateral areas. Median time between symptom onset and MRI was 238 minutes. T2'-values were significantly reduced within the apparent diffusion coefficient -lesion when compared with contralateral healthy tissue (83 ms [67, 97] versus 97 ms [91, 111]; P<0.003). In perfusion-restricted tissue, T2'-values were also significantly lower when compared with contralateral healthy tissue (ie, for time to peak, ≥0 s 93 ms [86, 102] versus 104 [90, 110]; P=0.008) but were significantly higher than within the apparent diffusion coefficient lesion. The severity of the perfusion impairment had no influence on median T2'-values. Motion-corrected T2'-mapping reveals significant and gradually declining values from healthy to perfusion-disturbed to apparent diffusion coefficient-restricted tissue. Current T2'-mapping can differentiate between the ischemic core and the perfusion-impaired areas but not on its own between penumbral and oligemic tissue.

P-016 High Specificity Identification of Acute Large Vessel Stroke: Maximising Cohort Selection for Potential Mechanical Thrombectomy

Background and purposeWith mechanical thrombectomy (MT), 0–4.5hr patients ineligible for IV tPA likely benefit from recanalization therapy, and >4.5 hr patients may also benefit. However, limited centers provide MT. To...

Successful recanalization with multimodality endovascular interventional therapy in acute ischemic stroke

Stroke is an important cause of death and disability in adults. However, effective treatments for patients with acute ischemic stroke are limited. Intravenous recombinant tissue plasminogen activator (iv rtPA) within 4.5 h after onset has been approved as a standard treatment for patients with acute ischemic stroke. However, due to time constraints, less than one percent of acute ischemic stroke patients in Thailand are able to obtain iv rtPA. Although endovascular interventional therapy has not yet been approved as standard treatment in acute ischemic stroke, it is the one of the potentially effective treatment options. There are several reliable methods of endovascular therapy for acute ischemic stroke patients. Endovascular interventional therapy has rarely been done in Thailand. We report seven patients with successful recanalization after endovascular treatment in acute large vessel stroke from a single stroke center in Thailand. Patient screening and selection with multimodal imaging protocol and multimodality methods of endovascular interventional therapy are described.

Abstract 2974: Sex Differences in Correlation of Cerebral Infarction Volume with Functional Outcome

Background: Studies have suggested worse functional outcomes in women after acute ischemic stroke. Following intravenous thrombolysis, they have higher recanalization rates; however, sex-based differential outcomes are poorly studied in large vessel occlusion +− intra-arterial therapy. We sought to ascertain the correlation between infarcted brain tissue volume and functional outcome in women as compared to men who were potential neurointerventional therapy candidates. Methods: We retrospectively queried our prospectively maintained acute potential neurointerventional candidate and neuroimaging patient database (n=283) and correlated final DWI cerebral infarction volume with functional outcomes as measured by the modified Rankin Scale [MRS] at hospital discharge and 30 days. Results: Median age was 69 [56,79] and 185 patients received intra-arterial therapy including 103 women (55.7%). There were no differences in age or admission NIHSS score, initial or final DWI infarction volumes, premorbid MRS, site of large vessel occlusion, pre-intervention collateral grade, TIMI or TICI grade, or recanalization rate between the sexes. Spearman correlation coefficients (r 2 ) between final DWI infarction volume and functional outcomes for neurointerventionally treated men as compared to women were 0.45 [men, p=.0009] versus (vs) 0.12 [women, p=.41] for discharge MRS; 0.78 [men, p&lt;.0001] vs -0.27 [women, p=.17] for 30 day MRS, and 0.78 [men, p&lt;.001] vs -0.26 (women, p=.26]. For all women vs men irrespective of treatment, the r 2 values were 0.53 [men, p&lt;.0001] vs 0.35 [women, p=.009] for discharge MRS; 0.60 [men, p&lt;.0001] vs 0.05 [women, p=.73] for 30 day MRS; and 0.68 [men, p&lt;.001] vs -0.078 [women, p=.66]. These differences were confirmed by an ordinal logistic regression analysis. Conclusions: Despite comparable baseline functional status, treatment rate, occlusion site, initial and final infarction volumes, and recanalization rates, final infarction volume correlates strongly with functional outcome in men but not in women. This data suggests fundamental differences in neurophysiological or social factors between men and women in response to acute large vessel stroke, the nature of which deserves to be more fully investigated.

Abstract 2907: Endostroke-Registry: An International Multicenter Registry for Mechanical Recanalization Procedures in Acute Stroke

Mechanical recanalization prodecures are increasingly used to treat acute large-vessel stroke. High recanalization rates in patients with proximal vessel occlusions and the direct control of therapeutic success are its major strengths. On the other hand, its clinical benefit as well as the risk/benefit ratio are not well defined by now. Randomized trials comparing endovascular approaches with systemic thrombolysis are still ongoing and present-day evidence is based on non-controlled single arm trials and case series. Within the larger studies (Penumbra Pivotal Stroke Trial, MERCI-trials) a discrepancy between favourable angiographic results and poor clinical outcomes was noticeable with high rates (up to 70%) of patients with “futile recanalization”, leading to a “clinical-angiographic mismatch”. Many factors may contribute to this paradox finding, e.g. patient selection bias (inclusion of patients with contraindications for systemic thrombolysis), too long treatment time windows and periprocedural measures (e.g. general anaesthesia). Amongt these, many other factors need clarification before mechanical recanalization therapies can be used in a broader clinical fashion. To adress some of these questions, we launched an international, investigator-driven, multicenter registry (ENDOSTROKE) to accumulate robust data on clinical outcome, complication rates and procedural issues. Its primary main outcome measure is the clinical status 90 days (or later) after intervention assessed by the MRS. Important clinical, angiographic and procedural parameters, especially time-aspects (e.g. periprocedural time loss or duration of mechanical recanalization procedures) will be analyzed with respect to their influence on clinical outcome. The registry is completely independent from industrial sponsoring and is registered at www.clinicaltrials.gov with NCT01399762 . The registry is currently recruiting patients. 13 mostly academic centers participate in the registry, 120 patients were entered by now in the database with the intention to include approximately 500 patients. At the International Stroke Conference the structure and goals of ENDOSTROKE will be presented.