Acute Intracranial Large Artery Occlusion Research Articles

Association of baseline core volume and early midline shift in acute stroke patients with a large ischaemic core.

Midline shift (MLS) is troublesome problem that may occur in patients with a large infarct core (LIC) and may be related to the baseline infarct core volume. The purpose of this study was to explore the relationship between baseline infarct core volume and early MLS presence. Patients with acute intracranial large artery occlusion and a pretreatment relative cerebral blood flow (rCBF) <30% volume ≥50 ml on CT perfusion (CTP) were included, clinical outcomes following endovascular treatment (EVT) were retrospectively analyzed. The primary endpoint was MLS within 48 h (early MLS presence). The association between baseline ICV and early MLS presence was evaluated with multivariable regression. Ultimately, 95 patients were included, and 29.5% (28/95) of the patients had early MLS. The number of patients with a baseline rCBF < 15% volume (median [interquartile range], 46 [32-60] vs. 29 [19-40]; P < 0.001) was significantly larger in the early severe MLS presence group. A baseline rCBF < 15% volume showed significantly better predictive accuracy for early MLS presence than an rCBF < 30% volume (area under the curve, 0.74 vs. 0.64, P = 0.0023). In addition, an rCBF < 15% volume ≥40 ml (odds ratio, 4.34 [95% CI, 1.571-11.996]) was associated with early MLS presence after adjustment for sex, age, baseline National Institutes of Health Stroke Scale score, onset-to-recanalization time. In patients with an acute LIC following EVT, a pretreatment infarct core volume > 40 ml based on an rCBF < 15% showed good predictive value for early MLS occurrence.

Association Between Occlusion Type and Etiology of Acute Intracranial Large Artery Occlusion.

Objective: To investigate the diagnostic efficiency of truncal-type occlusion and branching-site occlusion in determining the etiology of intracranial large artery occlusion related acute ischemic stroke (AIS).Methods: Patients with intracranial large artery occlusion related AIS who received stent retriever (SR) thrombectomy from November 2014 to June 2019 were included in the study. All patients underwent angiography before SR thrombectomy, which was used to evaluate the occlusion type. Differences in the distribution of occlusion types in intracranial atherosclerosis (ICAS) and embolism were assessed, and the diagnostic indicators, including the area under the ROC curve (AUC), sensitivity, and specificity were calculated.Results: Of the 115 AIS patients with intracranial large artery occlusion, 42 were classified as having ICAS, and 73 having an embolism. In the ICAS group, branching-site occlusion was responsible for 3 (7%) cases and truncal-type occlusion for 39 (93%) cases, while in the embolism group, branching-site occlusion was responsible for 66 (90%) cases and truncal-type occlusion for 7 (10%) cases; the difference was statistically significant (all P < 0.01). The AUC for ICAS predicted by truncal-type occlusion was 0.916, with a sensitivity of 92.86%, and specificity of 90.41%.Conclusion: Truncal-type occlusion showed a high predictability of ICAS. Determine the etiology of intracranial large artery occlusion related AIS before SR thrombectomy may be most helpful in setting up optimal endovascular treatment strategies.

Antegrade Blood Flow on 4-Dimensional Computed Tomography Angiography Predict Stroke Subtype in Patients With Acute Large Artery Occlusion.

BackgroundThe purpose of this study was to determine whether the presence of antegrade blood flow was related to stroke subtype in patients with acute intracranial large artery occlusion.Methods and ResultsThe prospectively collected data for consecutive patients who had occlusion of the unilateral M1 segment of the middle cerebral artery with or without internal carotid artery and received reperfusion therapy were retrospectively reviewed. Stroke causes were determined according to the Trial of ORG 10172 in Acute Stroke Treatment standard. We defined antegrade flow as early opacification at the distal interface of the clot with subsequent distal extension on 4‐dimensional computed tomography angiography. A total of 387 large artery occlusion patients were analyzed (229 men and 158 women; mean age, 71±14 years), including 77 (19.9%) with large artery atherosclerosis (LAA), 206 (53.2%) with cardioembolism, and 104 (26.9%) with undetermined causes. Antegrade flow was found in 206 (53.2%) patients, and 181 (46.8%) presented with retrograde flow. The rate of antegrade flow was much higher in patients with LAA than in those with cardioembolism (85.7% versus 42.2%, P<0.001). Multivariable logistic regression revealed that presence of antegrade flow was significantly associated with cuse of LAA after adjusting for confounding factors, when setting cardioembolism as reference (odds ratio, 5.650; 95% confidence interval, 2.451–13.158; P<0.001). The sensitivity, specificity, and positive and negative predictive values of the antegrade flow for predicting LAA were 43.1%, 91.5%, 85.7%, and 57.8%, respectively.ConclusionsUsing 4‐dimensional computed tomography angiography, antegrade flow can be identified in more than half of acute anterior large artery occlusion patients and occurs more frequently in those with LAA as the cause of stroke.

Usefulness of stent strut deformity during thrombectomy for predicting the stroke etiology in acute large artery occlusion

BackgroundStent retriever thrombectomy has been regarded as the standard treatment for acute intracranial large artery occlusion. As fast recanalization is the most important factor for favorable outcomes in patients with stroke, defining the etiology is important for the treatment of acute large vessel occlusion. We aimed to investigate whether full-length stent visibility during thrombectomy could provide information on the stroke etiology or the clot characteristics using the stent strut deformity during thrombectomy. Materials and methodsIntra-arterial thrombectomy was performed on 46 patients with Trevo stent as the first endovascular thrombectomy device. Patients were assigned to the full expansion group or the stent deformity group based on the shape of the stent strut during the endovascular procedure. The presence of stent deformity during the procedure, underlying intracranial atherosclerotic stenosis (ICAS), and residual stenosis at the occlusion site on the final conventional angiography, follow-up magnetic resonance angiography, or computed tomography angiography were retrospectively assessed. ResultsRecanalization without underlying arterial stenosis at the occlusion site was observed in 92.9 % (26/28 patients) and 50.0 % (8/16 patients) of the full expansion and stent deformity groups (p = 0.002), respectively. A significantly lower proportion of patients in the full expansion group demonstrated ICAS-related occlusion compared with that in the stent deformity group (3.6 % vs. 43.8 %, respectively; p = 0.002). ConclusionsThe degree of stent expansion during thrombectomy in acute large artery occlusion can be a useful predictor of the stroke etiology and potentially helpful to the operator for endovascular treatment planning.

Number of Stent Retriever Passes Associated With Futile Recanalization in Acute Stroke.

Background and Purpose- Stent retriever (SR) thrombectomy has become the mainstay of treatment of acute intracranial large artery occlusion. However, it is still not much known about the optimal limit of SR attempts for favorable outcome. We evaluated whether a specific number of SR passes for futile recanalization can be determined. Methods- Patients who were treated with a SR as the first endovascular modality for their intracranial large artery occlusion in anterior circulation were retrospectively reviewed. The recanalization rate for each SR pass was calculated. The association between the number of SR passes and a patient's functional outcome was analyzed. Results- A total of 467 patients were included. Successful recanalization by SR alone was achieved in 82.2% of patients. Recanalization rates got sequentially lower as the number of passes increased, and the recanalization rate achievable by ≥5 passes of the SR was 5.5%. In a multivariable analysis, functional outcomes were more favorable in patients with 1 to 4 passes of the SR than in patients without recanalization (odds ratio [OR] was 8.06 for 1 pass; OR 7.78 for 2 passes; OR 6.10 for 3 passes; OR 6.57 for 4 passes; all P<0.001). However, the functional outcomes of patients with ≥5 passes were not significantly more favorable than found among patients without recanalization (OR 1.70 with 95% CI, 0.42-6.90 for 5 passes, P=0.455; OR 0.33 with 0.02-5.70, P=0.445 for ≥6 passes). Conclusions- The likelihood of successful recanalization got sequentially lower as the number of SR passes increased. Five or more passes of the SR became futile in terms of the recanalization rate and functional outcomes.

Prediction of the Multisegment Clot Sign on Dynamic CT Angiography of Cardioembolic Stroke.

The multisegment clot sign has been observed at the site of large-artery occlusion in patients with acute ischemic stroke. This study aimed to assess its occurrence rate and relationship with stroke etiologies in patients with acute intracranial large-artery occlusion. We included consecutive patients with acute ischemic stroke who had acute intracranial large-artery occlusion and underwent perfusion CT within 8 hours after stroke onset. The multisegment clot sign was assessed on dynamic CT angiography derived from perfusion CT. The stroke etiologies were defined by the international Trial of Org 10172 in Acute Stroke Treatment criteria. Poisson regression analyses and diagnostic testing were used to investigate the relationship between the multisegment clot sign and stroke etiologies. Finally, 194 patients with intracranial large-artery occlusion were enrolled. According to the Trial of Org 10172 in Acute Stroke Treatment criteria, 110 (56.7%) patients were diagnosed with cardioembolism; 43 (22.2%), with large-artery atherosclerosis; and 41 (21.1%), with undetermined etiology. The multisegment clot sign was found in 74 (38%) patients. Poisson regression analysis showed that the presence of the multisegment clot sign was significantly higher in patients with cardioembolism than in those with large-artery atherosclerosis (52.7% versus 9.3%; prevalence ratio, 1.53; 95% confidence interval, 1.03-2.90; P = .037). For determined etiologies, the sensitivity, specificity, and positive and negative predictive values of the multisegment clot sign for predicting cardioembolism were 52.7%, 90.7%, 93.5%, and 42.9%, respectively. The presence of the multisegment clot sign on dynamic CTA specifically indicates intracranial large-artery occlusion caused by an embolism from a cardiac source, which may be useful for acute management and secondary prevention of stroke.

Acute basilar artery occlusion: Endovascular Interventions versus Standard Medical Treatment (BEST) Trial-Design and protocol for a randomized, controlled, multicenter study.

Rationale Endovascular treatment plus standard medical therapy is superior to standard medical therapy alone for acute anterior proximal intracranial large artery occlusion strokes. The benefit of endovascular treatment in acute ischemic stroke caused by basilar artery occlusion remains unproven. Aim This study compares the safety and efficacy of endovascular treatment plus standard medical therapy versus standard medical therapy alone in acute ischemic stroke due to basilar artery occlusion. Design The study is a multicenter randomized control trial with blinded outcome assessment. A projected total 344 subjects with acute basilar arterial occlusion within 8 h of estimated occlusion time will be enrolled over three years in China. Patients will be assigned to endovascular treatment plus standard medical therapy and standard medical therapy alone group in 1:1 ratio for study centers. Study outcomes The primary outcome measure is a favorable functional outcome, defined as a modified Rankin Score of 0-3 at 90 days. The primary safety measure is mortality at 90 days. Trial registration ClinicalTrials.gov (NCT 02441556). Summary The BEST trial will provide valuable insights into the safety and efficacy of endovascular treatment for acute ischemic stroke patients with basilar artery occlusion.

Importance of truncal-type occlusion in stentriever-based thrombectomy for acute stroke.

To investigate whether angiographically defined occlusion type could predict of the etiology of acute intracranial large artery occlusion and the stentriever response. We reviewed consecutive patients with acute intracranial large artery occlusion who underwent endovascular treatment and examined their workups for embolic sources. Patient demographics, laboratory findings, hyperdense artery sign, and angiographic occlusion type (truncal-type or branching-site occlusion) were compared between embolic sources (+) and (-) groups. These variables were also compared between stentriever failure and success groups. Details of endovascular procedures were also compared according to occlusion type. A total of 259 patients (mean age 70.3 years; M:F = 132:127) were finally included. Of these patients, 216 (83.4%) were assigned to the embolic sources (+) group after thorough evaluation. Young age, no coronary artery disease, and truncal-type occlusion (odds ratio [OR] 9.07; 95% confidence interval [CI] 3.74-22.0) were independently associated with the embolic source (-) group. Of the overall group, 224 patients (86.5%) underwent stentriever-based endovascular treatment. Hypertension, diabetes, high C-reactive protein level, and truncal-type occlusion (OR 32.2; 95% CI 7.78-133.0) were independent predictors of stentriever failure. Truncal-type occlusion was associated with more reocclusion (77.3% vs 5.0%), resulting in recanalization failure by the stentriever (81.8% vs 20.3%), a longer puncture-to-recanalization time (118.0 vs 49.5 minutes), and more rescue treatment for final successful recanalization (78.9% vs 7.0%). Angiographic occlusion type is an independent predictor of stentriever refractoriness and of the underlying stroke mechanism.

Primary stent retrieval for acute intracranial large artery occlusion due to atherosclerotic disease.

Background and PurposeThe goal of stent retriever–based thrombectomy is removal of embolic clots in patients with intracranial large artery occlusion. However, outcomes of stent retrieval may differ between acute arterial occlusions due to intracranial atherosclerotic disease (IAD) and those due to embolism. This case series describes the outcomes of stent retriever–based thrombectomy and rescue treatments in 9 patients with IAD-related occlusion.MethodsAmong patients who underwent endovascular treatment for acute intracranial large artery occlusion, those in whom stent retrieval was attempted as first-line treatment were included in this review. IAD was defined as significant fixed focal stenosis at the occlusion site, which was evident on final angiographic assessment or observed during endovascular treatment.ResultsMedian number of stent retriever passes was 2 (range, 1-3), and temporary bypass was seen in all patients. Immediate partial recanalization (arterial occlusive lesion grade 2-3) was observed in 7 patients. Immediate modified thrombolysis in cerebral infarction grade 2b-3 was seen in 6 patients, but the lesions often required rescue treatment due to reocclusion or flow insufficiency. In terms of rescue treatments, angioplasty and intra-arterial tirofiban infusion seemed to be effective.ConclusionsOur findings suggest that stent retrieval can effectively remove thrombi from stenotic lesions and achieve partial recanalization despite the tendency toward reocclusion in most patients with IAD-related occlusion. Further research into the use of rescue treatments, such as tirofiban infusion and angioplasty, is warranted.

Endovascular Treatment in Two Cases of Bilateral Ischemic Stroke

Acute bilateral intracranial large artery occlusion is a rare occurrence that can lead to bihemispheric ischemia and potentially devastating functional consequences. We discuss two cases that initially presented with unilateral symptoms and did not show signs of bilateral arterial occlusions on the initial MRI imaging. This became evident while performing the angiographic study at the beginning of the endovascular procedure. Both patients were successfully treated with bilateral mechanical thrombectomy as a complement to intravenous thrombolysis. We describe our method of simultaneous sequential bilateral thrombectomy. To our knowledge, this is the first report of successful endovascular therapy in bilateral ischemic stroke.

Leukoaraiosis and Sex Predict the Hyperacute Ischemic Core Volume

Leukoaraiosis (LA) and male sex have been associated with decreased cerebrovascular reactivity, which potentially adversely affects tissue viability in acute stroke. Therefore, we aimed to elucidate the contribution of LA-severity and sex to the extent of the hyperacute ischemic core volume after intracranial large artery occlusion. We analyzed data from 87 patients with acute intracranial large artery occlusion who had acute multimodal computed tomography-imaging. LA-severity was assessed using the van Swieten scale on noncontrast computed tomography. Computed tomography perfusion data were analyzed using automatic calculation of the mean transit time and hyperacute cerebral blood volume defects. Multivariate linear and logistic regression analyses were used to identify independent predictors of the hyperacute infarct-volume. Severe LA (van Swieten Scale, 3-4; odds ratio, 43.22; 95% CI, 6.26-298.42; P<0.001) and male sex (odds ratio, 7.52; 95% CI, 1.38-40.86; P=0.020) were independently associated with a hyperacute cerebral blood volume-lesion >25 mL on multivariate logistic regression analysis. Multivariate linear regression analysis confirmed the association between severe LA (P<0.001) and male sex (P=0.01) with larger cerebral blood volume-lesions. There was no significant difference in the absolute or relative mean transit time-lesion volumes when stratified by LA-severity or sex. Women had significantly smaller cerebral blood volume-lesion volumes compared with men (P=0.036). Severe LA and male sex are associated with larger infarct cores, which adds to the notion that sex and LA alter the brain's intrinsic susceptibility to acute cerebral ischemia. Future, larger studies are needed to confirm our observation that women have smaller core volumes and its significance.

Leukoaraiosis Predicts Poor 90-Day Outcome after Acute Large Cerebral Artery Occlusion

Background: To date limited information regarding outcome-modifying factors in patients with acute intracranial large artery occlusion (ILAO) in the anterior circulation is available. Leukoaraiosis (LA) is a common finding among patients with ischemic stroke and has been associated with poor post-stroke outcomes but its association with ILAO remains poorly characterized. This study sought to clarify the contribution of baseline LA and other common risk factors to 90-day outcome (modified Rankin Scale, mRS) after stroke due to acute anterior circulation ILAO. Methods: We retrospectively analyzed 1,153 consecutive patients with imaging-confirmed ischemic stroke during a 4-year period (2007–2010) at a single academic institution. The final study cohort included 87 patients with acute ILAO subjected to multimodal CT imaging within 24 h of symptom onset. LA severity was assessed using the van Swieten scale on non-contrast CT. Leptomeningeal collaterals were graded using CT angiogram source images. Hemorrhagic transformation (HT) was determined on follow-up CT. Multivariate logistic regression controlling for HT, treatment modality, demographic, as well as baseline clinical and imaging characteristics was used to identify independent predictors of a poor outcome (90-day mRS >2). Results: The median National Institutes of Health Stroke Scale (NIHSS) at baseline was 15 (interquartile range 9–21). Twenty-four percent of the studied patients had severe LA. They were more likely to have hypertension (p = 0.028), coronary artery disease (p = 0.015), poor collaterals (p < 0.001), higher baseline NIHSS (p = 0.003), higher mRS at 90 days (p < 0.001), and were older (p = 0.002). Patients with severe LA had a uniformly poor outcome (p < 0.001) irrespective of treatment modality. Poor outcome was independently associated with higher baseline NIHSS (p < 0.001), worse LA (graded and dichotomized, p < 0.001), reduced leptomeningeal collaterals (graded and dichotomized, p < 0.001), presence of HT (p < 0.001), presence of parenchymal hemorrhages (p = 0.01), baseline mRS (p = 0.002), and older age (p = 0.043). The association between severe LA (p = 0.0056; OR 13.86; 95% CI 1.94–∞) and baseline NIHSS (p = 0.0001; OR 5.11; 95% CI 2.07–14.49 for each 10-point increase) with poor outcome maintained after adjustment for confounders in the final regression model. In this model, there was no significant association between presence of HT and poor outcome (p = 0.0572). Conclusion: Coexisting LA may predict poor functional outcome in patients with acute anterior circulation ILAO independent of other known important outcome predictors such as comorbid state, admission functional deficit, collateral status, hemorrhagic conversion, and treatment modality.

Abstract 2269: Leukoaraiosis Predicts 90-day Outcome After Intracranial Large Artery Occlusion

Background: Intracranial large artery occlusion (ILAO) accounts for a significant number of ischemic strokes and predicts a poor outcome. However, factors modifying the outcome following ILAO remain incompletely characterized. Leukoaraiosis (LA), which is a frequent finding in stroke patients, has been associated with poor post-stroke outcomes. However, its contribution to patient outcome after ILAO remains to be clarified. We sought to determine the association between LA-severity and 90-day outcomes in patients following anterior circulation ILAO. Methods: We retrospectively analyzed 1153 consecutive patients with imaging confirmed ischemic stroke during a 4-year period (2007-2010). The final study cohort included 87 patients with acute ILAO subjected to multimodal CT-imaging within 24 hours of symptom onset. LA-severity was assessed using the van Swieten scale on non-contrast CT. Leptomeningeal collaterals were graded using CT-angiogram source images. Hemorrhagic infarction was determined on follow-up CT. Multivariate logistic regression controlling for hemorrhagic infarction, treatment modality, demographic, as well as baseline clinical and imaging characteristics was used to identify independent predictors for outcome. Results: Factors independently associated with poor outcome (90-day mRS≥3) were admission NIHSS (p=0.0001; OR 5.11; 95% CI, 2.07-14.49 for each 10-point increase) and severe LA (p=0.0056; OR 13.86; 95% CI, 1.94-∞; Figure ). There was a trend for an association between presence of hemorrhagic conversion and poor outcome (p=0.0572; OR 4.82; CI 0.96-32.65). Compared to patients with none-to-moderate LA, patients with severe LA were more likely to have hypertension (p=0.027), coronary artery disease (p=0.008), poor collaterals (p&lt;0.001), higher admission NIHSS (p=0.003), higher mRS at 90 days (p&lt;0.001), and they were older (p=0.002). Patients with severe LA had a uniformly poor outcome (p&lt;0.001). Conclusion: In addition to NIHSS, the severity of pre-existing LA has substantial impact on outcome in patients with acute ILAO and may prove to be an important factor to guide clinical decision making. Figure: Functional outcome by Leukoaraiosis grades Functional outcome at 90 days (modified Rankin Score, mRS) stratified by severity of Leukoaraiosis (LA) grades (van Swieten Score 0-2 vs. 3-4, P&lt;0.001). Numbers indicate n per mRS-category.