Functional Outcome Following Stroke Thrombectomy in Clinical Practice

Endovascular thrombectomy in patients with anterior circulation stroke: an emulated real-world comparison

BACKGROUND

Endovascular thrombectomy (EVT) has been proven effective in anterior circulation stroke due to large vessel occlusion (LVO). However, translation from randomized clinical trials (RCTs) with highly selected patients to real-world requires confirmation, particularly to identify associations outside of strict selection criteria.

AIMS

This study aims to compare functional outcomes after EVT in real-world with those reported in RCTs, and to identify associations with functional outcome after EVT outside RCT-criteria.

METHODS

This study analyzed longitudinal German real-world data from the Stroke Research Consortium in Northern Bavaria (STAMINA) cohort from January, 2015 to June, 2019. We conducted a trial emulation, comparing patients with anterior circulation stroke and LVO meeting selection criteria for RCTs investigating EVT (1) predominantly within 6 hours with those from HERMES meta-analysis, and (2) within 6-24 hours with those from AURORA meta-analysis. We (3) analyzed treatment effects of EVT and association with functional outcome in patients treated outside RCT criteria.

RESULTS

Of 598 patients, 281 (47.0%) met RCT-criteria for treatment within 6 hours (hereinafter STAMINA-HERMES), 74 (12.4%) met RCT-criteria for treatment within 6-24 hours (STAMINA-AURORA), and 277 (46.3%) patients received EVT outside RCT-criteria. We observed no difference in rates of functional independence or mortality, comparing STAMINA-HERMES with HERMES meta-analysis (mRS 0-1: n=120/281 [43%] vs. 291/633 [46%], p=0.36; mortality: n=34/281 [12%] vs. 97/633 [15%], p=0.20), and STAMINA-AURORA with AURORA meta-analysis (mRS 0-1: n=26/74 [35%] vs. 122/266 [46%], p=0.10, mortality: n=10/74 [14%] vs. 45/266 [17%], p=0.48). Patients treated outside RCT-criteria had worse outcome (mRS 0-1: n=38/277 [14%], mortality: n=90/277 [32%], both p<0.001); possibly driven by pre-existing functional dependence (n=172/277 [62%]). Compared to matched controls, EVT outside of RCT-criteria was associated with lower mortality (absolute treatment effect: -14%, 95% Confidence Interval [CI] -23 to -5, p<0.01), but not with recovery to functional independence or premorbid functional status (treatment effect: 4%, CI -4 to 11, p=0.34), which was associated with lower NIHSS (Odds ratio [OR] 0.86, CI 0.80-0.92, p<0.001) and age (OR 0.95, CI 0.93-0.98, p=0.002).

CONCLUSIONS

Translation of EVT outcomes reported in RCTs into real-world is possible, however, almost half of patients did not meet trial criteria. Identification of patients who functionally benefit from frequently performed EVT outside RCT-criteria requires further investigation.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04357899.

Endovascular treatment of primary M3 occlusion stroke in clinical practice: analysis of the German Stroke Registry

BACKGROUND

Endovascular treatment (ET) options for acute stroke due to distal middle cerebral artery occlusions are rapidly evolving, but data on outcome and safety are sparse. We therefore performed an analysis of patients undergoing ET for primary M3 occlusions in routine clinical practice in a nationwide registry.

METHODS

Patients enrolled between 01/20 and 12/21 in the prospective, multicenter German Stroke Registry-Endovascular Treatment (GSR-ET) were screened for mechanical thrombectomy performed for primary M3 occlusion. We analyzed neurological deficit as measured by the National Institute of Health Stroke Scale (NIHSS), symptomatic intracranial hemorrhage (sICH), thrombectomy technique, successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score of 2b-3) and functional outcome as measured by the modified Rankin Scale (mRS) at discharge and 90 days.

RESULTS

Out of 5574 patients, 11 patients (0.2%, median age 80 years, 54.5% female) underwent ET for primary M3 occlusion. All patients had pre-admission mRS ≤ 1, median NIHSS on admission was 8, and successful reperfusion was achieved in 6/11 patients (54.5%). While no vasospasm, dissection or perforation was reported, symptomatic intracranial hemorrhage occurred in 2 patients (18.2%). Favorable outcome (mRS ≤ 2) was achieved in 6/11 patients (54.5%) at 90-day follow-up.

CONCLUSIONS

ET for primary M3 occlusions is rarely performed. While technically feasible, the procedure's potential benefits must be carefully weighed against its associated risks, including clinically relevant complications. Caution and further research is needed to optimize patient selection for this intervention.

TRIAL REGISTRATION

GSR-ET; ClinicalTrials.gov Identifier: NCT03356392; Trial Registration Date: 11/29/2017.

Incidence and outcome of perforations during medium vessel occlusion compared with large vessel occlusion thrombectomy

BACKGROUND

Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation.

METHODS

In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0-2) and all-cause mortality at 90 days. Binomial test, chi-squared test and t-test for unpaired samples were used for statistical analysis.

RESULTS

During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%, p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%, p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation.

CONCLUSIONS

In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

Periprocedural unfractionated heparin bolus during endovascular treatment in acute ischemic stroke does more harm than good

BACKGROUND

Unfractionated heparin (UFH) bolus is occasionally administered during endovascular treatment (EVT) to reduce thrombotic complications in acute ischemic stroke patients. However, the MR CLEAN-MED trial showed an increase in symptomatic intracranial hemorrhages (sICH) and a non-significant shift towards worse functional outcome with UFH administration. We aimed to analyze the impact of periprocedural UFH bolus in a real-world setting in anterior (ACS) and posterior circulation stroke (PCS) patients.

METHODS

We analyzed data from the German Stroke Registry-Endovascular Treatment using propensity score matching. Primary outcome was the modified Rankin Scale at 3 months, and secondary outcome measures included mortality, angiographic outcomes, post-EVT National Institute of Health Stroke Scale scores and ICH at 24 hours.

RESULTS

Among 13,082 patients, 7948 with ACS (UFH bolus use in 15%) and 841 with PCS (UFH bolus use in 16.3%) were included in the propensity score matching analysis. Applying MR CLEAN-MED study criteria, UFH bolus was associated with worse functional outcomes (odds ratio [OR] 1.44; 95% CI 1.06-1.96). Analyzing all ACS and PCS patients, UFH bolus did not provide any net benefit. In ACS patients treated with intravenous thrombolysis (IVT), UFH bolus use was associated with worse functional outcomes (OR 2.40; 95% CI 1.34 to 5.06).

CONCLUSION

Our findings show transferability of the MR CLEAN-MED results into a real-world setting, confirming a negative effect of periprocedural UFH on functional outcome in this subgroup of patients. Considering all ACS and PCS patients, periprocedural UFH did not provide a net benefit and appears to be harmful, particularly in IVT-treated patients.

Decoding Molecular Mechanisms Underlying Outcomes After Ischemic Stroke Thrombectomy by RNA Sequencing of Retrieved Clots

BACKGROUND

Transcriptomic profiling has emerged as a powerful tool for exploring the molecular landscape of ischemic stroke clots and providing insights into the pathophysiological mechanisms underlying stroke progression and recovery. In this study, we aimed to investigate the relationship between stroke clot transcriptomes and stroke thrombectomy outcome, as measured by early neurological improvement (ENI) 30 (i.e., a 30% reduction in NIHSS at 24 h post-thrombectomy).

HYPOTHESIS

We hypothesized that there exist distinct clot gene expression patterns between good and poor neurological outcomes.

METHODS

Transcriptomic analysis of 32 stroke clots retrieved by mechanical thrombectomy was conducted. Transcriptome data of these clots were analyzed to identify differentially expressed genes (DEGs), defined as those with a log(fold-change) ≥ 1.5 and q < 0.05 between samples with good and poor early neurological outcomes. Gene ontology and bioinformatics analyses were performed on genes with p < 0.01 to identify enriched biological processes and Ingenuity Pathway Analysis canonical pathways. Moreover, AUC analysis assessed the predictive power of DEGs for 90-day function outcome (mRS ≤ 2) and cellular composition of clot was predicted using CIBERSORT. We also assessed whether differential enrichment of immune cell types could indicate patient survival.

RESULTS

A total of 41 DEGs were identified. Bioinformatics showed that enriched biological processes and pathways emphasized the chronic immune response and matrix metalloproteinase inhibition. Moreover, 25 of the DEGs were found to be significant predictors of 90-day mRS. These genes were indicative of monocytes enrichment and neutrophil depletion in patients with poorer outcomes.

CONCLUSION

Our study revealed a distinct gene expression pattern and dysregulated biological pathways associated with ENI. This expression pattern was also predictive of long-term outcome, suggesting a biological link between those ENIs and 90-day mRS.

Endovascular therapy in patients with internal carotid artery occlusion and patent circle of Willis

BACKGROUND

Occlusion of the internal carotid artery (ICA) may extend into the middle or anterior cerebral artery (ICA-T) or be confined to the intracranial (ICA-I) or extracranial segment (ICA-E). While there is excellent evidence for endovascular therapy (EVT) in ICA-T occlusions, studies on EVT in non-tandem ICA-I or ICA-E occlusions are scarce.

OBJECTIVE

To characterize EVT-treated patients with ICA-I- and ICA-E occlusion by comparing them with ICA-T occlusions.

METHODS

The German Stroke Registry (GSR), a national, multicenter, prospective registry was searched for EVT-treated patients with isolated ICA occlusion between June 2015 and December 2021. We stratified patients by ICA occlusion site: (a) ICA-T, (b) ICA-I, (c) ICA-E. Baseline factors, procedural variables, technical (modified Thrombolysis in Cerebral Infarction (mTICI)), and functional outcomes (modified Rankin scale score at 3 months) were analyzed.

RESULTS

Of 13 082 GSR patients, 2588 (19.8%) presented with an isolated ICA occlusion, thereof 1946 (75.2%) ICA-T, 366 (14.1%) ICA-I, and 276 (10.7%) ICA-E patients. The groups differed in age (77 vs 76 vs 74 years, Ptrend=0.02), sex (53.4 vs 48.9 vs 43.1% female, Ptrend<0.01), and stroke severity (median National Institutes of Health Stroke Scale score at admission 17 vs 14 vs 13 points, Ptrend<0.001). In comparison with ICA-T occlusions, both ICA-I and ICA-E occlusions had lower rates of successful recanalization (mTICI 2b/3: 85.4% vs 80.4% vs 76.3%; aOR (95% CI for ICA-I vs ICA-T 0.71 (0.53 to 0.95); aOR (95% CI) for ICA-E vs ICA-T 0.57 (0.42 to 0.78)). In adjusted analyses, ICA-E occlusion was associated with worse outcome when compared with ICA-T occlusion (mRS ordinal shift, cOR (95% CI) 0.70 (0.52 to 0.93)).

CONCLUSION

Patient characteristics and outcomes differ substantially between ICA-T, ICA-I, and ICA-E occlusions. These results warrant further studies on EVT in ICA-I and ICA-E patients.

Initiation of mechanical thrombectomy in an insular setting with helicopter transfer: a 2-year experience from the first, complete, tertiary stroke center in the Caribbean

BACKGROUND

This is the first cohort study of patients treated with mechanical thrombectomy (MT) for acute ischemic stroke in the French West Indies, with a mothership center and helicopter transfer.

OBJECTIVE

To describe the population and to evaluate imaging, clinical, and time metric outcomes, in order to assess the feasibility and adjust the territorial organization.

METHODS

In this observational study, we retrospectively analyzed our prospectively collected data of a population of consecutive patients treated with MT for anterior and posterior circulation large vessel occlusions. Primary outcome was 3-month functional independence (modified Rankin Scale score ≤2). Secondary outcomes included aerial and terrestrial times of arrival, in-hospital delays, demographics, imaging and clinical data at onset, discharge, and at 3 months. We compared the results of the mothership and drip-and-ship paradigms.

RESULTS

Between January 2020 and December 2021, 223 patients were included (74% mothership, 26% drip-and-ship). Mean National Institutes of Health Stroke Scale (NIHSS) score of the population was 16 before MT, with significant reduction (NIHSS score 6) at discharge (9 mothership, 12 drip-and-ship, P=0.025). There was significant difference in onset-to-operation room times among the two centers (335 min mothership, 500 min drip-and-ship, P=0.004). Successful recanalization (modified Thrombolysis in Cerebral Infarction score 2b-3) was 80.3%. Functional independence at 3 months was 35%, symptomatic intracranial hemorrhage was 11%, and the complication rate was 9.4%, all without statistically significant difference between the two groups.

CONCLUSION

The population has distinct risk factors. MT with helicopter transfer is feasible in the French West Indies. Reduction of prehospital and in-hospital times is mandatory; evaluation of the territorial strategy is underway, to avoid over-selection of transferred patients.

Automated detection of early signs of irreversible ischemic change on CTA source images in patients with large vessel occlusion

PURPOSE

To create and validate an automated pipeline for detection of early signs of irreversible ischemic change from admission CTA in patients with large vessel occlusion (LVO) stroke.

METHODS

We retrospectively included 368 patients for training and 143 for external validation. All patients had anterior circulation LVO stroke, endovascular therapy with successful reperfusion, and follow-up diffusion-weighted imaging (DWI). We devised a pipeline to automatically segment Alberta Stroke Program Early CT Score (ASPECTS) regions and extracted their relative Hounsfield unit (rHU) values. We determined the optimal rHU cut points for prediction of final infarction in each ASPECT region, performed 10-fold cross-validation in the training set, and measured the performance via external validation in patients from another institute. We compared the model with an expert neuroradiologist for prediction of final infarct volume and poor functional outcome.

RESULTS

We achieved a mean area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity of 0.69±0.13, 0.69±0.09, 0.61±0.23, and 0.72±0.11 across all regions and folds in cross-validation. In the external validation cohort, we achieved a median [interquartile] AUC, accuracy, sensitivity, and specificity of 0.71 [0.68-0.72], 0.70 [0.68-0.73], 0.55 [0.50-0.63], and 0.74 [0.73-0.77], respectively. The rHU-based ASPECTS showed significant correlation with DWI-based ASPECTS (rS = 0.39, p<0.001) and final infarct volume (rS = -0.36, p<0.001). The AUC for predicting poor functional outcome was 0.66 (95%CI: 0.57-0.75). The predictive capabilities of rHU-based ASPECTS were not significantly different from the neuroradiologist's visual ASPECTS for either final infarct volume or functional outcome.

CONCLUSIONS

Our study demonstrates the feasibility of an automated pipeline and predictive model based on relative HU attenuation of ASPECTS regions on baseline CTA and its non-inferior performance in predicting final infarction on post-stroke DWI compared to an expert human reader.

Mechanical thrombectomy in anterior vs. posterior circulation stroke: A systematic review and meta-analysis

BACKGROUND

High-quality evidence exists for mechanical thrombectomy (MT) treatment of acute ischemic stroke (AIS) due to large vessel occlusion of the anterior circulation (AC-LVO). The evidence for MT treatment of posterior circulation large vessel occlusion (PC-LVO) is weaker, largely drawn from lower quality studies specific to PC-LVO and extrapolated from findings in AC-LVO, and ambiguous with regards to technical success. We performed a systematic review and meta-analysis to compare the technical success and functional outcomes of MT in PC-LVO versus AC-LVO patients.

METHODS

We identified comparative studies reporting on patients treated with MT in AC-LVO versus PC-LVO. The primary outcome of interest was thrombolysis in cerebral infarction (TICI) ≥ 2b. Secondary outcomes included rates of TICI 3, 90-day functional independence, first-pass-effect, average number of passes, and 90-day mortality. A separate random effects model was fit for each outcome measure.

RESULTS

Twenty studies with 12,911 patients, 11,299 (87.5%) in the AC-LVO arm and 1612 (12.5%) in the PC-LVO arm, were included. AC-LVO and PC-LVO patients had comparable rates of successful recanalization [OR = 1.02 [95% CI: 0.79-1.33], p = 0.848). However, the AC-LVO group had greater odds of 90-day functional independence (OR = 1.26 [95% CI: 1.00; 1.59], p = 0.050) and lower odds of 90-day mortality (OR = 0.58 [95% CI: 0.43; 0.79], p = 0.002).

CONCLUSIONS

MT achieves similar rates of recanalization with a similar safety profile in PC-LVO and AC-LVO patients. Patients with PC-LVO are less likely to achieve functional independence after MT. Future studies should identify PC-LVO patients who are likely to achieve favourable functional outcomes.

Thrombolysis treatment protected impairment of functional ability, quality of life and fatigue seven years after stroke

OBJECTIVES

We studied quality of life, functional outcome, depression, and fatigue of ischemic stroke patients treated with or without thrombolysis seven years post-stroke.

MATERIALS AND METHODS

A total of 204 ischemic stroke patients treated with or without thrombolysis during 2013-2015. After seven years the 136 survivors were assessed with telephone interview, which included questions about subjective quality of life (European Quality of Life-5 Dimensions), depression, fatigue with Fatigue Severity Scale, functional ability assessed with Barthel Index and Modified Rankin Scale, living conditions, need of care, and medical aids.

RESULTS

At admission patients with thrombolysis had higher National Institutes of Health Stroke Scale scores compared with those not treated with thrombolysis. At seven years post-stroke, 99% of alive patients answered the questionnaires. There were no group differences concerning functional outcome, quality of life, depression, fatigue, or insomnia. The Barthel Index was normal in both groups. The quality of life was good in both groups without group differences in any domains. Of all patients, 68% reported no problems in usual activities, and 61% were without pain. Anxiety or depression were experienced by 19% of all stroke patients, while fatigue was present in 32% of cases.

CONCLUSIONS

Seven years post-stroke the quality of life was good and functional outcome remained in good level in both study groups. One third experienced fatigue, while every fifth experienced depression. The thrombolysis treatment seems to protect from decreased quality of life, fatigue, and decreased mobility, self-care, and usual activities despite more severe stroke.

Whole Blood Viscosity and Cerebral Blood Flow in Acute Ischemic Stroke

Existing effective treatments for ischemic stroke restore blood supply to the ischemic region using thrombolysis or mechanical removal of clot. However, it is increasingly recognized that successful removal of occlusive thrombus from the large artery-recanalization, may not always be accompanied by successful restoration of blood flow to the downstream tissues-reperfusion. Ultimately, brain tissue survival depends on cerebral perfusion, and a functioning microcirculation. Because capillary diameter is often equal to or smaller than an erythrocyte, microcirculation is largely dependent on erythrocyte rheological (hemorheological) factors such as whole blood viscosity (WBV). Several studies in the past have demonstrated elevated WBV in stroke compared with healthy controls. Also, elevated WBV has shown to be an independent risk factor for stroke. Elevated WBV leads to endothelial dysfunction, decreases nitric oxide-dependent flow-mediated vasodilation, and promotes hemostatic alterations/thrombosis, all leading to microcirculation sludging. Compromised microcirculation further leads to decreased cerebral perfusion. Hence, modulating WBV through pharmacological agents might be beneficial to improve cerebral perfusion in stroke. This review discusses the effect of elevated WBV on endothelial function, hemostatic alterations, and thrombosis leading to reduced cerebral perfusion in stroke.

Hybrid Clot Histomic-Transcriptomic Models Predict Functional Outcome After Mechanical Thrombectomy in Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

Histologic and transcriptomic analyses of retrieved stroke clots have identified features associated with patient outcomes. Previous studies have demonstrated the predictive capacity of histology or expression features in isolation. Few studies, however, have investigated how paired histologic image features and expression patterns from the retrieved clots can improve understanding of clot pathobiology and our ability to predict long-term prognosis. We hypothesized that computational models trained using clot histomics and mRNA expression can predict early neurological improvement (ENI) and 90-day functional outcome (modified Rankin Scale Score, mRS) better than models developed using histological composition or expression data alone.

METHODS

We performed paired histological and transcriptomic analysis of 32 stroke clots. ENI was defined as a delta-National Institutes of Health Stroke Score/Scale > 4, and a good long-term outcome was defined as mRS ≤2 at 90 days after procedure. Clots were H&E-stained and whole-slide imaged at 40×. An established digital pathology pipeline was used to extract 237 histomic features and to compute clot percent composition (%Comp). When dichotomized by either the ENI or mRS thresholds, differentially expressed genes were identified as those with absolute fold-change >1.5 and q < 0.05. Machine learning with recursive feature elimination (RFE) was used to select clot features and evaluate computational models for outcome prognostication.

RESULTS

For ENI, RFE identified 9 optimal histologic and transcriptomic features for the hybrid model, which achieved an accuracy of 90.8% (area under the curve [AUC] = 0.98 ± 0.08) in testing and outperformed models based on histomics (AUC = 0.94 ± 0.09), transcriptomics (AUC = 0.86 ± 0.16), or %Comp (AUC = 0.70 ± 0.15) alone. For mRS, RFE identified 7 optimal histomic and transcriptomic features for the hybrid model. This model achieved an accuracy of 93.7% (AUC = 0.94 ± 0.09) in testing, also outperforming models based on histomics (AUC = 0.90 ± 0.11), transcriptomics (AUC = 0.55 ± 0.27), or %Comp (AUC = 0.58 ± 0.16) alone.

CONCLUSION

Hybrid models offer improved outcome prognostication for patients with stroke. Identified digital histology and mRNA signatures warrant further investigation as biomarkers of patient functional outcome after thrombectomy.

Effect of heart rate on poor outcome in stroke patients treated with intra-arterial thrombectomy

BACKGROUND AND PURPOSE

The relationship between heart rate and the prognosis of patients with large vessel occlusion strokes treated with mechanical thrombectomy (MT) is not well established. This study aimed to evaluate the association of mean heart rate and heart rate variability (HRV) with the clinical outcomes after MT therapy.

METHODS

Acute ischemic stroke patients undergoing MT therapy were prospectively recruited from March 2020 to November 2022. Their heart rate was collected every hour for the initial 72 h after MT procedure, and the variability of heart rate was measured by standard deviation (SD) and coefficient of variation (CV). All-cause mortality and worsening of functional outcome (change in modified Rankin Scale (mRS) score) at 3-month were captured. Binary logistic regression was used to evaluate the association between heart rate indicators and all-cause mortality. Ordinal logistic regression was used to evaluate the association between heart rate indicators and worsening of functional outcome.

RESULTS

Among 191 MT-treated patients, 51(26.7%) patients died at 3-month after stroke. Increased mean heart rate per 10-bpm, heart rate SD and CV per 5-unit were all associated with the increased risk of mortality (adjusted hazard ratio [aHR] with 95% CI: 1.29 [1.09-1.51], 1.19 [1.07-1.32], 1.14 [1.03-1.27]; respectively). Patients in the highest tertile of heart rate SD had an increased risk of mortality (4.62, 1.70-12.52). After using mRS as a continuous variable, we found increased mean heart rate per 10-bpm, heart rate SD and CV per 5-unit were associated with the worsening of functional outcome (adjusted odds ratio [aOR] with 95% CI: 1.35 [1.11-1.64], 1.27 [1.05-1.53], 1.19 [1.02-1.40]; respectively). A linear relationship was observed between mean heart rate or heart rate SD and mortality; while all of the heart rate measures in this study showed a linear relationship with the worsening of functional outcome.

CONCLUSIONS

Higher mean heart rate and HRV were associated with the increased risk of 3-month all-cause mortality and worse functional outcome after MT therapy for AIS patients.

Aspiration only versus stent retriever only thrombectomy in basilar artery occlusion: a propensity score-matched analysis of the German Stroke Registry

BACKGROUND

Endovascular treatment has become the standard care for acute basilar artery occlusion (BAO). Uncertainty persists about the optimal thrombectomy technique.

OBJECTIVE

To compare aspiration thrombectomy with stent retriever thrombectomy in patients with BAO in a multicenter real-world patient population.

METHODS

We analyzed data from the German Stroke Registry-Endovascular Treatment (GSR-ET). Patients with isolated BAO who underwent either aspiration or stent retriever thrombectomy were compared, including propensity score matching (PSM). The primary outcome measure was the modified Rankin Scale shift analysis at 90 days. Secondary outcomes included symptomatic intracranial hemorrhage (sICH), procedure complications, and metrics.

RESULTS

Of 13 082 patients in the GSR-ET, 387 patients (mean age 72.0±13.1 years; 45.0% female) fulfilled the inclusion criteria. The thrombectomy technique was aspiration only in 195 (50.4%) and stent retriever only in 192 (49.6%) patients. Functional outcome did not differ between the groups, either before (common OR (cOR) 0.94; 95% CI 0.64 to 1.38) or after PSM (cOR=1.37; 95% CI 0.90 to 2.09). There was no significant difference in sICH (2.6 vs 5.5%; P=0.231; OR=0.46; 95% CI 0.14 to 1.47), but aspiration thrombectomy demonstrated fewer procedure-related complications (4.6% vs 12.5%; P=0.017), a shorter procedure duration (24 vs 48 min; P<0.001), and higher first pass recanalization rates (75.1% vs 44.8%; P<0.001).

CONCLUSIONS

In this study both aspiration and stent retriever thrombectomy showed equal efficacy in terms of functional outcome in patients with BAO. However, procedure complications and metrics might favor aspiration over stent retriever thrombectomy.

How much of the outcome improvement after successful recanalization is explained by follow-up infarct volume reduction?

BACKGROUND

Follow-up infarct volume (FIV) is used as surrogate for treatment efficiency in mechanical thrombectomy (MT). However, previous works suggest that MT-related FIV reduction has only limited association with outcome comparing MT independently of recanalization success versus medical care. It remains unclear to what extent the relationship between successful recanalization versus persistent occlusion and functional outcome is explained by FIV reduction.

OBJECTIVE

To determine whether FIV mediates the relationship between successful recanalization and functional outcome.

METHODS

All patients from our institution enrolled in the German Stroke Registry (May 2015-December 2019) with anterior circulation stroke; availability of the relevant clinical data, and follow-up-CT were analyzed. The effect of FIV reduction on functional outcome (90-day modified Rankin Scale (mRS) score ≤2) after successful recanalization (Thrombolysis in Cerebral Infarction ≥2b) was quantified using mediation analysis.

RESULTS

429 patients were included, of whom, 309 (72 %) had successful recanalization and 127 (39%) had good functional outcome. Good outcome was associated with age (OR=0.89, P<0.001), pre-stroke mRS score (OR=0.38, P<0.001), FIV (OR=0.98, P<0.001), hypertension (OR=2.08, P<0.05), and successful recanalization (OR=3.57, P<0.01). Using linear regression in the mediator pathway, FIV was associated with Alberta Stroke program Early CT Score (coefficient (Co)=-26.13, P<0.001), admission National Institutes of Health Stroke Scale score (Co=3.69, P<0.001), age (Co=-1.18, P<0.05), and successful recanalization (Co=-85.22, P<0.001). Successful recanalization increased the probability of good outcome by 23 percentage points (pp) (95% CI 16pp to 29pp). 56% (95% CI 38% to 78%) of the improvement in good outcome was explained by FIV reduction.

CONCLUSION

56% (95% CI 38% to 78%) of outcome improvement after successful recanalization was explained by FIV reduction. Results corroborate pathophysiological assumptions and confirm the value of FIV as an imaging endpoint in clinical trials. 44% (95% CI 22% to 62%) of the improvement in outcome was not explained by FIV reduction and reflects the remaining mismatch between radiological and clinical outcome measures.

The effect of anesthesia on hemodynamics and outcome of patients undergoing thrombectomy after acute ischemic stroke: a retrospective analysis

BACKGROUND

Anesthesia during thrombectomy remains a matter of debate. We retrospectively investigated the influence of intraprocedural blood pressure and type of anaesthetic agent on 3-month functional outcome and mortality in stroke patients undergoing mechanical thrombectomy under general anesthesia in a single center study.

METHODS

All patients suffering from stroke who presented between January 2019 and July 2021 at Ziekenhuis Oost-Limburg Genk, Belgium and who received thrombectomy were included. Patient's characteristics and outcome data had been collected for benchmarking. Detailed perioperative data were exported from the electronic anesthesia records and clinically validated. Patients were stratified by peri-operative presence of hypotension (MAP < 65 mmHg at any time point) versus no-hypotension (MAP ≥ 65 mmHg).

RESULTS

All 98 patients received mechanical thrombectomy under general anesthesia. Thirty-six percent (n = 35) was hypotensive peri-operatively at any time point. Proportion of sevoflurane use was higher in non-hypotensive patients compared to hypotensive patients (73% (n = 45) vs. 51% (n = 18), p = 0.04). Peri-operative use of vasopressors was higher in the hypotensive group compared to non-hypotensive (88% (n = 30) vs. 63% (n = 39), p = 0.008). Proportion of patients with good functional outcome at 3 months (mRS 0-2) was higher in non-hypotensive patients compared to hypotensive patients 44% (n = 27) vs. 24% (n = 8), p < 0.05. 90-day mortality was lower in non-hypotensive patients compared to hypotensive patients 21% (n = 13) vs. 43% (n = 15), (p = 0.02).

CONCLUSION

Patients who are hypotensive at any given time during thrombectomy under general anesthesia may have worse neurological outcome compared to non-hypotensive patients. The best anaesthetic management for mechanical thrombectomy needs to be clarified prospectively in large multicenter studies.

Endovascular thrombectomy for acute ischemic stroke in Saudi Arabia: A single-center experience

PURPOSE

This study aimed to investigate the outcomes of endovascular thrombectomy-treated patients in King Fahad Medical City, Riyadh, Saudi Arabia.

METHODS

A retrospective cohort study of acute ischemic stroke patients treated with endovascular thrombectomy. Patients were included in the study between January 2015 and December 2022. Good outcomes were defined as a modified Rankin Scale (mRS) of 0-2 at 90 days. Multivariate logistic regression analysis was performed to identify the independent factors associated with good outcomes.

RESULTS

During the study period, 369 patients with acute ischemic stroke (mean ± SD age, 61/- 15.1 yrs; 55.4 % male) underwent mechanical thrombectomy. Median National Institute of Health Stroke Scale (NIHSS) 15. Intravenous thrombolysis was administered to 34.5 % of the patients. Successful recanalization in the anterior circulation was achieved in 84.8 % of patients. Data from mRS performed after 90 days in the anterior circulation were available for 71.2 % of the patients. Of these, 41 % showed a good outcome, and the mortality rate was 22.4 %. The significant factors associated with good outcomes were age, NIHSS score, Alberta Stroke Program Early Computed Tomography Score (ASPECTS), and short arterial puncture to recanalization.

CONCLUSION

The number of patients who underwent endovascular thrombectomy has increased over time. The treatment outcomes and mortality were comparable with those of previous endovascular thrombectomy registries despite the high prevalence of DM, lower ASPECT score, and prolonged onset-to-recanalization time.

Prediction of tissue outcome in acute ischemic stroke based on single-phase CT angiography at admission

Introduction

In acute ischemic stroke, prediction of the tissue outcome after reperfusion can be used to identify patients that might benefit from mechanical thrombectomy (MT). The aim of this work was to develop a deep learning model that can predict the follow-up infarct location and extent exclusively based on acute single-phase computed tomography angiography (CTA) datasets. In comparison to CT perfusion (CTP), CTA imaging is more widely available, less prone to artifacts, and the established standard of care in acute stroke imaging protocols. Furthermore, recent RCTs have shown that also patients with large established infarctions benefit from MT, which might not have been selected for MT based on CTP core/penumbra mismatch analysis.

Methods

All patients with acute large vessel occlusion of the anterior circulation treated at our institution between 12/2015 and 12/2020 were screened (N = 404) and 238 patients undergoing MT with successful reperfusion were included for final analysis. Ground truth infarct lesions were segmented on 24 h follow-up CT scans. Pre-processed CTA images were used as input for a U-Net-based convolutional neural network trained for lesion prediction, enhanced with a spatial and channel-wise squeeze-and-excitation block. Post-processing was applied to remove small predicted lesion components. The model was evaluated using a 5-fold cross-validation and a separate test set with Dice similarity coefficient (DSC) as the primary metric and average volume error as the secondary metric.

Results

The mean ± standard deviation test set DSC over all folds after post-processing was 0.35 ± 0.2 and the mean test set average volume error was 11.5 mL. The performance was relatively uniform across models with the best model according to the DSC achieved a score of 0.37 ± 0.2 after post-processing and the best model in terms of average volume error yielded 3.9 mL.

Conclusion

24 h follow-up infarct prediction using acute CTA imaging exclusively is feasible with DSC measures comparable to results of CTP-based algorithms reported in other studies. The proposed method might pave the way to a wider acceptance, feasibility, and applicability of follow-up infarct prediction based on artificial intelligence.

Spontaneous Behavioural Recovery Following Stroke Relates to the Integrity of Parietal and Temporal Regions

Stroke is a devastating disease that results in neurological deficits and represents a leading cause of death and disability worldwide. Following a stroke, there is a degree of spontaneous recovery of function, the neural basis of which is of great interest among clinicians in their efforts to reduce disability following stroke and enhance rehabilitation. Conventionally, work on spontaneous recovery has tended to focus on the neural reorganization of motor cortical regions, with comparably little attention being paid to changes in non-motor regions and how these relate to recovery. Here we show, using structural neuroimaging in a macaque stroke model (N = 31) and by exploiting individual differences in spontaneous behavioural recovery, that the preservation of regions in the parietal and temporal cortices predict animal recovery. To characterize recovery, we performed a clustering analysis using Non-Human Primate Stroke Scale (NHPSS) scores and identified a good versus poor recovery group. By comparing the preservation of brain volumes in the two groups, we found that brain areas in integrity of brain areas in parietal, temporal and somatosensory cortex were associated with better recovery. In addition, a decoding approach performed across all subjects revealed that the preservation of specific brain regions in the parietal, somatosensory and medial frontal cortex predicted recovery. Together, these findings highlight the importance of parietal and temporal regions in spontaneous behavioural recovery.

Cortical atrophy on baseline computed tomography imaging predicts clinical outcome in patients undergoing endovascular treatment for acute ischemic stroke

OBJECTIVE

Multiple variables beyond the extent of recanalization can impact the clinical outcome after acute ischemic stroke due to large vessel occlusions. Here, we assessed the influence of small vessel disease and cortical atrophy on clinical outcome using native cranial computed tomography (NCCT) in a large single-center cohort.

METHODS

A total of 1103 consecutive patients who underwent endovascular treatment (EVT) due to occlusion of the middle cerebral artery territory were included. NCCT data were visually assessed for established markers of age-related white matter changes (ARWMC) and brain atrophy. All images were evaluated separately by two readers to assess the inter-observer variability. Regression and machine learning models were built to determine the predictive relevance of ARWMC and atrophy in the presence of important baseline clinical and imaging metrics.

RESULTS

Patients with favorable outcome presented lower values for all measured metrics of pre-existing brain deterioration (p < 0.001). Both ARWMC (p < 0.05) and cortical atrophy (p < 0.001) were independent predictors of clinical outcome at 90 days when controlled for confounders in both regression analyses and led to a minor improvement of prediction accuracy in machine learning models (p < 0.001), with atrophy among the top-5 predictors.

CONCLUSION

NCCT-based cortical atrophy and ARWMC scores on NCCT were strong and independent predictors of clinical outcome after EVT.

CLINICAL RELEVANCE STATEMENT

Visual assessment of cortical atrophy and age-related white matter changes on CT could improve the prediction of clinical outcome after thrombectomy in machine learning models which may be integrated into existing clinical routines and facilitate patient selection.

KEY POINTS

• Cortical atrophy and age-related white matter changes were quantified using CT-based visual scores. • Atrophy and age-related white matter change scores independently predicted clinical outcome after mechanical thrombectomy and improved machine learning-based prediction models. • Both scores could easily be integrated into existing clinical routines and prediction models.

A Study of Factors Affecting Functional Outcomes in Patients With Successful Recanalization by Mechanical Thrombectomy

BACKGROUND AND PURPOSE

Reperfusion therapy is typically performed in cases with acute cerebral infarction. Mechanical thrombectomy (MT) achieves superior recanalization and favorable outcomes. However, some patients have poor functional prognosis despite successful recanalization. We investigated factors affecting functional prognosis after MT with good reperfusion.

METHODS

Among the 205 consecutive cases with ischemic stroke treated with MT at our center from January 1, 2019 to March 31, 2021, 168 with successful recanalization were included. Factors affecting early neurological improvement (ENI) and modified Rankin Scale (mRS) scores were reviewed retrospectively.

RESULTS

There were 93 (55%) cases with ENI and 75 (45%) without ENI. The times from onset to recombinant tissue-type plasminogen activator administration and recanalization in ENI cases were shorter than those in non-ENI cases. However, non-ENI cases had significantly higher Fazekas grades for white matter lesions. In multivariate analysis, the Fazekas grade was related to ENI (odds ratio [OR]=0.572, 95% confidence interval [CI]=0.345-0.948). The mRS score at discharge was 0-2 in 64 cases (good outcome) and 3-6 in 104 cases (poor outcome). Patients with a poor outcome had a significantly higher age, National Institutes of Health Stroke Scale (NIHSS) score, and Fazekas grade. Multivariate analysis revealed that the NIHSS score (OR=1.073, 95% CI=1.020-1.129) and Fazekas grade (OR=2.162, 95% CI=1.458-3.205) at hospitalization affected the mRS score at discharge.

CONCLUSION

There is a correlation of greater severity of white matter lesions with poorer ENI and clinical outcomes at discharge post-MT.

Soluble PD-L1 reprograms blood monocytes to prevent cerebral edema and facilitate recovery after ischemic stroke

Acute cerebral ischemia triggers a profound inflammatory response. While macrophages polarized to an M2-like phenotype clear debris and facilitate tissue repair, aberrant or prolonged macrophage activation is counterproductive to recovery. The inhibitory immune checkpoint Programmed Cell Death Protein 1 (PD-1) is upregulated on macrophage precursors (monocytes) in the blood after acute cerebrovascular injury. To investigate the therapeutic potential of PD-1 activation, we immunophenotyped circulating monocytes from patients and found that PD-1 expression was upregulated in the acute period after stroke. Murine studies using a temporary middle cerebral artery (MCA) occlusion (MCAO) model showed that intraperitoneal administration of soluble Programmed Death Ligand-1 (sPD-L1) significantly decreased brain edema and improved overall survival. Mice receiving sPD-L1 also had higher performance scores short-term, and more closely resembled sham animals on assessments of long-term functional recovery. These clinical and radiographic benefits were abrogated in global and myeloid-specific PD-1 knockout animals, confirming PD-1+ monocytes as the therapeutic target of sPD-L1. Single-cell RNA sequencing revealed that treatment skewed monocyte maturation to a non-classical Ly6Clo, CD43hi, PD-L1+ phenotype. These data support peripheral activation of PD-1 on inflammatory monocytes as a therapeutic strategy to treat neuroinflammation after acute ischemic stroke.

Simulation of transportation of acute stroke patients in border regions

Determining the optimal transportation for each stroke patient is critically important to achieve the best possible outcomes. In border regions the next comprehensive stroke center may be just across an international border, but bureaucratic and financial hurdles may prevent a simple transfer to the next stroke center. We hypothesized that in regions close to international borders, patients may benefit from an "open border, closed transfer scenario", meaning that patients in whom a large vessel occlusion (LVO) is detected in the primary stroke center will benefit from a transfer to the nearest stroke center offering endovascular thrombectomy-even if this may be across a national border. We used the Swiss-German-French trinational region as an example for a region with several international borders within close proximity to one another, and compared two feasible scenarios; (a) a "closed borders, open transfer" scenario, where the patient is transported to any center in the same country, (b) an "open border, closed transfer" scenario, where patients are always transported to the nearby primary stroke center first and then to the nearest comprehensive stroke center in either the same or a neighboring country and (c) and "open borders, open transfer" scenario. The outcome of interest was the predicted probability of acute ischemic stroke patients to achieve a good outcome using a conditional probability model which predicts the likelihood of excellent outcome (modified Rankin scale score of 0-1 at 90 days post-stroke) for patients with suspected LVO. Results were modeled in a virtual map from which the ideal transport concept emerged. For an exemplary LVO stroke patient in Germany, the probability of a good outcome was higher in an open border, closed transfer scenario than with closed borders, open transfer (33.1 vs. 30.1%). Moreover, time to EVT would decrease from 232 min in the first scenario to 169 min in an open border, closed transfer scenario. The catchment area of the University Hospital Basel was almost double the size in an open border, closed transfer scenario compared to closed borders (1674 km2 vs. 2897 km2) and would receive transfers from 3 primary stroke centers in other countries (2 in Germany and 1 in France). Stroke patients showed a higher likelihood of good outcome in the "open border" scenarios without transfer restrictions to a specific healthcare system. This probably has implications for stroke treatment in all border regions where EVT eligible stroke patients may benefit from transport to the closest EVT capable center whenever possible, regardless of whether this hospital is located in the same or a neighboring country/jurisdiction.

Oral health and functional outcomes following mechanical thrombectomy for ischemic stroke

BACKGROUND

An association between poor dentition and the risk of ischemic stroke has previously been reported in the literature. In this study we assessed oral hygiene (OH), including tooth loss and the presence of dental disease, to determine if an association exists with functional outcomes following mechanical thrombectomy (MT) for large-vessel ischemic stroke.

METHODS

A retrospective review was conducted of consecutive adult patients at a single comprehensive stroke center who underwent MT from 2012 to 2018. Inclusion criteria included availability of CT imaging to radiographically assess OH. A multivariate analysis was performed, with the primary outcome being 90-day post-thrombectomy modified Rankin Scale (mRS) score >2.

RESULTS

A total of 276 patients met the inclusion criteria. The average number of missing teeth was significantly higher in patients with a poor functional outcome (mean (SD) 10 (11) vs 4 (6), p<0.001). The presence of dental disease was associated with poor functional outcome, including cavities (21 (27%) vs 13 (8%), p<0.001), periapical infection (18 (23%) vs 11 (6.7%), p<0.001), and bone loss (27 (35%) vs 11 (6.7%), p<0.001). Unadjusted, missing teeth was a univariate predictor of poor outcome (OR 1.09 (95% CI 1.06 to 1.13), p<0.001). After adjustment for recanalization scores and use of tissue plasminogen activator (tPA), missing teeth remained a predictor of poor outcome (OR 1.07 (95% CI 1.03 to 1.11), p<0.001).

CONCLUSION

Missing teeth and the presence of dental disease are inversely correlated with functional independence following MT, independent of thrombectomy success or tPA status.

Emergency admission plasma D-dimer: a novel predictor for symptomatic intracranial hemorrhage after thrombectomy in acute ischemic stroke

BACKGROUND

Symptomatic intracranial hemorrhage (sICH) is a common and severe complication in patients with acute ischemic stroke (AIS) after treatment with thrombectomy.

OBJECTIVE

To explore the ability of admission plasma D-dimer levels to predict sICH after thrombectomy.

METHODS

Between February 2018 and August 2021, consecutive patients with AIS who underwent thrombectomy at our single comprehensive stroke center were retrospectively enrolled. sICH was defined according to the criterion of the Heidelberg Bleeding Classification. Logistic regression analysis was performed to determine the risk factors of sICH. The overall discriminative ability of D-dimer levels in predicting sICH was evaluated by adopting a receiver operating characteristic (ROC) curve.

RESULTS

Of the 395 enrolled patients, 48 (12.2%) had sICH. Patients with sICH were older (72.9 vs 69.3 years, P=0.037), more often female (62.5% vs 45.5%, P=0.027), had higher D-dimer levels (2.70 vs 0.74 mg/L, P<0.001), higher National Institutes of Health Stroke Scale score (20 vs 15, P<0.001), lower Alberta Stroke Program Early CT Score (8 vs 9, P<0.001), a higher proportion of internal carotid artery occlusions (56.2% vs 30.3%, P<0.001), and less commonly had large-artery atherosclerosis stroke etiology (12.5% vs 32.3%, P=0.010) than patients without sICH. After adjustment for potential confounders, D-dimer levels (adjusted OR=2.45, 95% CI 1.75 to 3.43, P<0.001) remained significantly associated with sICH. Based on the ROC, the D-dimer as a predictor for predicting sICH, presented with a specificity of 86.2%, a negative predictive value of 94.6%, and an area under the curve of 0.774.

CONCLUSION

Elevated admission D-dimer levels are an independent predictor of sICH in patients with AIS after thrombectomy.

Thrombectomy in M2 occlusion compared to M1 occlusion: treatment effects of Thrombolysis In Cerebral Infarction (TICI) 2b and TICI 3 recanalization on functional outcome

BACKGROUND

Emerging data suggest that mechanical thrombectomy (MT) might also be safe and efficient for medium and distal occlusions. This study aims to compare average treatment effects on functional outcome of different degrees of recanalization after MT in patients with M2 occlusion and M1 occlusion.

METHODS

All patients enrolled in the German Stroke Registry (GSR) between June 2015 and December 2021 were analyzed. Inclusion criteria were stroke with primary M1 occlusion or M2 occlusion, and availability of relevant clinical data. 4259 patients were included, thereof 1353 with M2 occlusion and 2906 with M1 occlusion. Treatment effects were analyzed using double-robust inverse-probability-weighted regression-adjustment (IPWRA) estimators to control for confounding covariates. Binarized endpoint metrics were defined as good outcome with modified Rankin Scale (mRS) ≤2 at 90 days, and linearized endpoint metrics were defined as mRS shift pre-stroke to 90 days. Effects were evaluated for near complete recanalization (Thrombolysis In Cerebral Infarction scale (TICI) 2b) and complete recanalization (TICI 3).

RESULTS

Treatment effect estimation for TICI ≥2b versus TICI <2b in M2 occlusions showed an increase in the probability of a good outcome from 27% to 47% with a number-needed-to-treat (NNT) of 5. For M1 occlusions the probability of a good outcome increased from 16% to 38% with NNT 4.5. TICI 3 versus TICI 2b increased the probability of a good outcome by 7 percentage points in M1 occlusions; for M2 occlusions the beneficial effect was not significant.

CONCLUSIONS

Results suggest that successful recanalization with TICI ≥2b versus TICI <2b after MT in M2 occlusions provides significant patient benefit with treatment effects comparable to M1 occlusions. The probability of functional independence increased by 20 percentage points (NNT 5) and stroke-related mRS increase was reduced by 0.9 mRS points. In contrast to M1 occlusions, complete recanalization TICI 3 versus TICI 2b had lower additional beneficial effect.

Predicting outcome in acute stroke with large vessel occlusion-application and validation of MR PREDICTS in the ESCAPE-NA1 population

BACKGROUND

Predicting outcome after endovascular treatment for acute ischemic stroke is challenging. We aim to investigate differences between predicted and observed outcomes in patients with acute ischemic stroke treated with endovascular treatment and to evaluate the performance of a validated outcome prediction score.

PATIENTS AND METHODS

MR PREDICTS is an outcome prediction tool based on a logistic regression model designed to predict the treatment benefit of endovascular treatment based on the MR CLEAN and HERMES populations. ESCAPE-NA1 is a randomized trial of nerinetide vs. placebo in patients with acute stroke and large vessel occlusion. We applied MR PREDICTS to patients in the control arm of ESCAPE-NA1. Model performance was assessed by calculating its discriminative ability and calibration.

RESULTS

Overall, 556/1105 patients (50.3%) in the ESCAPE-NA1-trial were randomized to the control arm, 435/556 (78.2%) were treated within 6 h of symptom onset. Good outcome (modified Rankin scale 0-2) at 3 months was achieved in 275/435 patients (63.2%), the predicted probability of good outcome was 52.5%. Baseline characteristics were similar in the study and model derivation cohort except for age (ESCAPE-NA1: mean: 70 y vs. HERMES: 66 y), hypertension (72% vs. 57%), and collaterals (good collaterals, 15% vs. 44%). Compared to HERMES we observed higher rates of successful reperfusion (TICI 2b-3, ESCAPE-NA1: 87% vs. HERMES: 71%) and faster times from symptom onset to reperfusion (median: 201 min vs. 286 min). Model performance was good, indicated by a c-statistic of 0.76 (95%confidence interval: 0.71-0.81).

CONCLUSION

Outcome-prediction using models created from HERMES data, based on information available in the emergency department underestimated the actual outcome in patients with acute ischemic stroke and large vessel occlusion receiving endovascular treatment despite overall good model performance, which might be explained by differences in quality of and time to reperfusion. These findings underline the importance of timely and successful reperfusion for functional outcomes in acute stroke patients.

Impact of atrial fibrillation on the treatment effect of bridging thrombolysis in ischemic stroke patients undergoing endovascular thrombectomy: a multicenter international cohort study

BACKGROUND

The role of bridging intravenous thrombolysis (IVT) before endovascular thrombectomy (EVT) in the treatment of acute ischemic stroke (AIS) remains debatable. Atrial fibrillation (AF) associated strokes may be associated with reduced treatment effect from IVT. This study compares the effect of bridging IVT in AF and non-AF patients.

METHODS

This retrospective cohort study comprised anterior circulation large vessel occlusion (LVO) AIS patients receiving EVT alone or bridging IVT plus EVT within 6 hours of symptom onset. Primary outcome was good functional outcome defined as modified Rankin Scale (mRS) 0-2 at 90 days. Secondary outcomes were successful reperfusion defined as expanded Thrombolysis In Cerebral Infarction (eTICI) grading ≥2b flow, symptomatic intracerebral hemorrhage (sICH), and in-hospital mortality.

RESULTS

We included 705 patients (314 AF and 391 non-AF patients). The mean age was 68.6 years and 53.9% were male. The odds of good functional outcomes with bridging IVT was higher in the non-AF (adjusted odds ratio (aOR) 2.28, 95% CI 1.06 to 4.91, P=0.035) compared with the AF subgroups (aOR 1.89, 95% CI 0.89 to 4.01, P=0.097). However, this did not constitute a significant effect modification by the presence of AF on bridging IVT (interaction aOR 0.12, 95% CI -1.94 to 2.18, P=0.455). The rate of successful reperfusion, sICH, and mortality were similar between bridging IVT and EVT for both AF and non-AF patients.

CONCLUSION

The presence of AF did not modify the treatment effect of bridging IVT. Further individual patient data meta-analysis of randomized trials may shed light on the comparative efficacy of bridging IVT in AF versus non-AF LVO strokes.

Ischemic stroke patients with low DWI ASPECTS scores require puncture to recanalization within 30 min for large vessel occlusion

BACKGROUND

The clinical benefits of faster recanalization in acute large vessel occlusion are well recognized, but the optimal procedure time remains uncertain. The aim of this study was to identify patient characteristics that necessitate puncture-to-recanalization (P-R) time within 30 min to achieve favorable outcome.

METHODS

We evaluated the patients from a prospective, multicenter, observational registry of acute ischemic stroke patients. The study included patients who underwent endovascular therapy for ICA or MCA M1 occlusion and achieved successful recanalization. Patients were categorized into subgroups based on pre-treatment characteristics and the frequency of favorable outcomes was compared between P-R time < 30 min and ≥ 30 min. Interaction terms were incorporated into the models to assess the correlation between each patient characteristic and P-R time.

RESULTS

A total of 1053 patients were included in the study. Univariate analysis within each subgroup revealed a significant association between P-R < 30 min and favorable outcomes in patients with DWI ASPECTS ≤6, age > 85 and NIHSS ≥16. In the multivariable analysis, NIHSS, age, time from symptom recognition to puncture, and DWI ASPECTS were significant independent predictors of favorable outcomes. Notably, only DWI ASPECTS exhibited interaction terms with P-R < 30 min. The multivariable analysis indicated that P-R < 30 min was an independent predictor for favorable outcome in DWI ASPECTS ≤6 group, whereas not in DWI ≥7.

CONCLUSIONS

P-R time < 30 min is predictive of favorable outcomes; however, the effect depends on DWI ASPECTS. Target P-R time < 30 min is appropriate for patients with DWI ASPECTS ≤6.

Thrombus migration in ischemic stroke due to large vessel occlusion: a question of time

BACKGROUND

Thrombus migration (TM) is frequently observed in large vessel occlusion (LVO) ischemic stroke to be treated by endovascular thrombectomy (EVT). TM may impede complete recanalization and hereby worsen clinical outcomes. This study aimed to delineate factors associated with TM and clarify its impact on technical and functional outcome.

METHODS

All patients undergoing EVT due to LVO in the anterior circulation at two tertiary stroke centers between October 2015 and December 2020 were included. Source imaging data of all individuals were assessed regarding occurrence of TM by raters blinded to clinical data. Patient data were gathered as part of the German Stroke Registry, a multicenter, prospective registry assessing real-world outcomes. Technical outcome was assessed by modified Thrombolysis in Cerebral Infarction scale (mTICI). Functional outcome was assessed by modified Rankin Scale (mRS) at 3 months.

RESULTS

The study consisted of 512 individuals, of which 71 (13.8%) displayed TM. In adjusted analyses, TM was associated with longer time from primary imaging to reassessment in the angio suite (aOR 2.37 (1.47 to 3.84) per logarithmic step) and intravenous thrombolysis (IVT; aOR 4.07 (2.17 to 7.65)). In individuals with IVT, a needle-to-groin time >1 hour was associated with higher odds for TM (aOR 2.60 (1.20 to 5.99)). TM was associated with lack of complete recanalization (aORmTICI3 0.46 (0.24 to 0.90)) but TM did not worsen odds for good clinical outcome (aORmRS≤2_d90 0.89 (0.47 to 1.68)).

CONCLUSIONS

TM is associated with IVT and longer time between sequential assessments of thrombus location. Consequently, TM may be of high relevance in patients with drip-and-ship treatment.

Predictors of functional outcome after thrombectomy for M2 occlusions: a large scale experience from clinical practice

Mechanical thrombectomy (MT) for acute ischemic stroke with medium vessel occlusions is still a matter of debate. We sought to identify factors associated with clinical outcome after MT for M2-occlusions based on data from the German Stroke Registry-Endovascular Treatment (GSR-ET). All patients prospectively enrolled in the GSR-ET from 05/2015 to 12/2021 were analyzed (NCT03356392). Inclusion criteria were primary M2-occlusions and availability of relevant clinical data. Factors associated with excellent/good outcome (modified Rankin scale mRS 0-1/0-2), poor outcome/death (mRS 5-6) and mRS-increase pre-stroke to day 90 were determined in multivariable logistic regression. 1348 patients were included. 1128(84%) had successful recanalization, 595(44%) achieved good outcome, 402 (30%) had poor outcome. Successful recanalization (odds ratio [OR] 4.27 [95% confidence interval 3.12-5.91], p < 0.001), higher Alberta stroke program early CT score (OR 1.25 [1.18-1.32], p < 0.001) and i.v. thrombolysis (OR 1.28 [1.07-1.54], p < 0.01) increased probability of good outcome, while age (OR 0.95 [0.94-0.95], p < 0.001), higher pre-stroke-mRS (OR 0.36 [0.31-0.40], p < 0.001), higher baseline NIHSS (OR 0.89 [0.88-0.91], p < 0.001), diabetes (OR 0.52 [0.42-0.64], p < 0.001), higher number of passes (OR 0.75 [0.70-0.80], p < 0.001) and intracranial hemorrhage (OR 0.26 [0.14-0.46], p < 0.001) decreased the probability of good outcome. Additional predictors of mRS-increase pre-stroke to 90d were dissections, perforations (OR 1.59 [1.11-2.29], p < 0.05) and clot migration, embolization (OR 1.67 [1.21-2.30], p < 0.01). Corresponding to large-vessel-occlusions, younger age, low pre-stroke-mRS, low severity of acute clinical disability, i.v. thrombolysis and successful recanalization were associated with good outcome while diabetes and higher number of passes decreased probability of good outcome after MT in M2 occlusions. Treatment related complications increased probability of mRS increase pre-stroke to 90d.

Association of the time of day of EVT with clinical outcomes and benefit from successful recanalization after stroke

Experimental and neuroimaging studies suggest an influence of the time of day on acute infarct growth, but whether this could inform patient selection for acute treatments is uncertain. In a multicenter cohort of 9357 stroke patients undergoing endovascular treatment, morning treatment (05:00-10:59) was associated with lowest 90-day mRS scores (adjusted odds ratio, 1.27 [95% CI, 1.08-1.47]; p = 0.004). The association between successful recanalization and outcome was stronger in morning compared to evening-treated patients (pia  = 0.046) with treatment benefit persisting until 24 h for morning-treated compared to 11.5 h for evening-treated patients suggesting that the time of day might inform patient selection for EVT.

Demonstrating the Value of Routine Anesthesiologist Involvement in Acute Stroke Care: A Retrospective Chart Review

INTRODUCTION

The value of routine involvement of anesthesiologists during endovascular thrombectomy (EVT) for acute ischemic stroke has not been clearly demonstrated. At some institutions, anesthesiologists are involved only as needed, while at other institutions, anesthesiologists are involved from the beginning for every EVT.

METHODS

We retrospectively analyzed the workflow, intraprocedural variables and complications, and outcomes in acute ischemic stroke patients undergoing EVT at a comprehensive stroke center after implementation of routine involvement of an anesthesia team and compared this cohort with patients who received care from sedation-trained nurses working under the supervision of neurointerventionalists with the involvement of anesthesiologists on an as-needed basis.

RESULTS

Routine involvement of anesthesiologists was associated with improved workflow performance measures, including decreased median door-to-arterial puncture time (68 min; interquartile range (IQR), 15.5-94.5 min vs. 81 min; IQR, 53-104 min; P =0.001), in-room to arterial puncture time (11 min; IQR, 8-14 min vs. 15 min; IQR, 9-21 min; P <0.0001), and procedure time (51 min; IQR, 40-64 min vs. 60 min; IQR, 40-88.5 min; P =0.007). It was also associated with a nonsignificant trend towards lower rates of desaturation events (8.2% vs. 3.4%; P =0.082) and lower rates of conversion to general anesthesia (1.7% vs. 0%; P =0.160). Ninety-day modified Rankin scores were similar regardless of provider type.

CONCLUSION

Implementation of routine involvement of an anesthesia team during EVT was not associated with improved outcomes but was associated with improved efficiency and greater adherence to guidelines-based physiological parameters, supporting the routine involvement of anesthesiologists during EVT.

Aspiration thrombectomy with the Penumbra System for patients with stroke and late onset to treatment: a subset analysis of the COMPLETE registry

Background

The purpose of this study was to report the safety and performance of aspiration thrombectomy with the Penumbra System for patients with acute ischemic stroke (AIS) due to anterior circulation large vessel occlusion (LVO) and late onset to treatment.

Methods

This is a retrospective subset analysis of a global prospective multicenter registry (COMPLETE) that enrolled adults with AIS due to LVO and a pre-stroke modified Rankin Scale score (mRS) of 0 or 1 who were treated first-line with aspiration thrombectomy either alone (A Direct Aspiration First Pass Technique [ADAPT]) or in combination with the 3D Revascularization Device (ADAPT + 3D). This subset analysis included all patients in the registry who had anterior circulation LVO, an Alberta Stroke Program Early CT Score of at least 6, and late onset to treatment (>6 h from stroke onset to puncture).

Results

Of the 650 patients in the COMPLETE registry, 167 were included in this subset analysis. The rate of successful revascularization (modified thrombolysis in cerebral infarction score 2b-3 achieved) at the end of the procedure was 83.2%, the rate of good functional outcome (mRS 0-2) at 90 days was 55.4%, and the all-cause mortality rate at 90 days was 14.4%. No device-related serious adverse events (SAEs) occurred. Procedure-related SAEs occurred in 9 patients (5.4%) within 24 h and in 12 patients (7.2%) overall. The rate of successful revascularization was higher for patients treated first-line with ADAPT (88.0%) than for patients treated first-line with ADAPT + 3D (75.0%; p = 0.035); no significant difference was observed between the ADAPT and ADAPT + 3D groups for any other primary or secondary outcome.

Conclusion

For patients with AIS due to anterior circulation LVO and with late onset to treatment, aspiration thrombectomy with the Penumbra System appears to be safe and effective. The rates of good functional outcome and all-cause mortality from this study compared favorably with those rates from the medical management arms of the DAWN and DEFUSE-3 studies.

Clinical trial registration

https://www.clinicaltrials.gov, NCT03464565.

Endovascular treatment of acute tandem lesions in patients with mild anterior circulation stroke

BACKGROUND

In patients with mild strokes the risk-benefit ratio of endovascular treatment (EVT) for tandem lesions has yet to be evaluated outside of current guideline recommendations. This study investigates the frequency as well as procedural and safety outcomes in daily clinical practice.

METHODS

Using data from the German Stroke Registry-Endovascular Treatment (GSR-ET) we analyzed patients with anterior circulation stroke due to tandem-lesions and mild deficits. These patients were defined as ≤5 on the National Institutes of Health Stroke Scale (NIHSS). Recanalization was assessed with the modified Thrombolysis in Cerebral Infarction Scale (mTICI). Early neurological and long-term functional outcomes were assessed with the NIHSS change and modified Rankin scale (mRS), respectively. Safety assessment included periprocedural complications and the rate of symptomatic intracerebral hemorrhage (sICH).

RESULTS

A total of 61 patients met the inclusion criteria and were treated endovascularly for tandem lesions. The median age was 68 (IQR:59-76) and 32.9% (20) were female. Patients were admitted to the hospital with a median NIHSS score of 4 (IQR:2-5) and a median Alberta Stroke Programme Early CT Score (ASPECTS) of 9 (IQR:8-10). Successful recanalization (mTICI 2b-3) was observed in 86.9% (53). NIHSS decreased non-significantly (p=0.382) from baseline to two points (IQR:1-9) at discharge. Excellent (mRS≤1) and favorable (mRS≤2) long-term functional outcome at 90-days was 55.8% (29) and 69.2% (36), respectively. Mortality rates at 90-days were 9.6% (5) and sICH occurred in 8.2% (5).

CONCLUSIONS

EVT for tandem lesions in patients with mild anterior circulation stroke appears to be feasible but may lead to increased rates of sICH. Further studies comparing endovascular with best medical treatment (BMT) especially investigating the risk of periprocedural hemorrhagic complications, are needed.

Mechanical thrombectomy in ischemic stroke after cardiovascular procedures: a propensity-matched cohort analysis

BACKGROUND

Stroke after a cardiovascular procedure (CVP) is a devastating complication adversely affecting outcome. Mechanical thrombectomy (MT) has not been investigated systematically in this population.

OBJECTIVE

To carry out a retrospective study in patients undergoing MT for early stroke after CVP, aiming to further characterize this cohort of patients, and to evaluate the efficacy, safety, procedural characteristics, and outcome of MT.

METHODS

A single-center stroke registry of patients who received MT was analyzed. Baseline and procedural parameters, mortality, functional outcome, recanalization rates, and complications were evaluated. Propensity score matching was carried out, identifying a control cohort with non-periprocedural large vessel occlusion (LVO).

RESULTS

Overall 913 patients were included (mean age 73.0 (±13.0) years, 52.5% female, median National Institutes of Health Stroke Scale score 15 (10-19)). Eleven patients with a LVO after a recent (<30 days postoperatively) CVP were identified (n=3 transcatheter aortic valve and n=1 surgical aortic valve replacements (SAVR), n=3 coronary bypass grafting (CABG) surgeries, n=2 SAVR+CABG, and n=2 aortic surgeries). After matching, 8 patients in the CVP group were compared with 16 patients in the matched cohort. Comparable rates of reperfusion were achieved. Time from symptom onset to groin puncture (171.5 min (136.3, 178.3) vs 284.0 min (215.0, 490.5); p=0.039), as well as recanalization (195.0 min (146.0, 201.0) vs 419.0 min (274.0, 613.0); p=0.028) was faster in the CVP group. However, this was not reflected by an improved outcome (modified Rankin Scale score after 90 days: 5.5 (3.3, 6.0) vs 5.0 (4.0, 6.0), mortality after 90 days 50.0% vs 37.5%). Complications did not differ between the groups.

CONCLUSIONS

Use of MT for LVO stroke in patients after a recent CVP is a safe and efficient treatment in comparison with patients with a non-periprocedural LVO undergoing MT.

Decline of thrombolysis rates before endovascular therapy in patients with acute anterior circulation large vessel occlusion ischemic stroke: A multicenter analysis from the German Stroke Registry

INTRODUCTION

In recent years, the role of intravenous thrombolysis (IVT) before endovascular stroke treatment (EVT) has been discussed intensively. Whether the discussion was accompanied by changing rates of bridging IVT is unknown.

METHODS

Data were extracted from the prospectively maintained German Stroke Registry, including patients treated with EVT at one of 28 stroke centers in Germany between 2016 and 2021. Primary outcome parameters were the rate of bridging IVT (a) in the entire registry cohort and (b) in patients without formal contraindications to IVT (i.e. recent oral anticoagulants, time window ⩾4.5 h, extensive early ischemic changes) adjusted for demographic and clinical confounders.

RESULTS

10,162 patients (52.8% women, median age 77 years, median National Institutes of Health Stroke Scale score 14) were analyzed. In the entire cohort, the rate of bridging IVT decreased from 63.8% in 2016 to 43.6% in 2021 (average absolute annual decrease 3.1%, 95% CI 2.4%-3.8%), while the proportion of patients with at least one formal contraindication increased by only 1.2% annually (95% CI 0.6%-1.9%). Among 5460 patients without record of formal contraindications, the rate of bridging IVT decreased from 75.5% in 2016 to 63.2% in 2021 and was significantly associated with admission date in a multivariable model (average absolute annual decrease 1.4%, 95% CI 0.6%-2.2%). Clinical factors associated with lower odds of bridging IVT included diabetes mellitus, carotid-T-occlusion, dual antiplatelet therapy, and direct admission to a thrombectomy center.

CONCLUSION

We observed a substantial decline in bridging IVT rates independent of demographic confounders and not explained by an increase in contraindications. This observation deserves further exploration in independent populations.

Clinical significance and prevalence of subarachnoid hyperdensities on flat detector CT after mechanical thrombectomy: does it really matter?

BACKGROUND

Subarachnoid hyperdensities after mechanical thrombectomy (MT) are a common finding. However, it is often regarded as clinically insignificant.

OBJECTIVE

With this single-center investigation, to identify the prevalence of subarachnoid hyperdensities following MT, associated predictors, and the impact on the clinical outcome of the patients.

METHODS

383 patients from the stroke registry were analyzed for the presence of subarachnoid hyperdensities on flat detector CT (FDCT) directly after the completion of MT, and on follow-up dual-energy CT, then classified according to a visual grading scale. 178 patients were included with anterior circulation occlusions. Regression analysis was performed to identify significant predictors, and Kruskal-Wallis analysis and Χ2 test were performed to test the variables among the different groups. The primary outcome was the modified Rankin Scale (mRS) score at 90 days and was analyzed with the Wilcoxon-Mann-Whitney rank-sum test.

RESULTS

The prevalence of subarachnoid hyperdensities on FDCT was (66/178, 37.1%) with patients experiencing a significant unfavorable outcome (P=0.035). Significantly fewer patients with subarachnoid hyperdensities achieved a mRS score of ≤3 at 90 days 25/66 (37.9%) vs 60/112 (53.6%), P=0.043). In addition, mortality was significantly higher in the subarachnoid hyperdensities group (34.8% vs 19.6%, P=0.024). Distal occlusions and a higher number of device passes were significantly associated with subarachnoid hyperdensities (P=0.026) and (P=0.001), respectively. Patients who received intravenous tissue plasminogen activator had significantly fewer subarachnoid hyperdensities (P=0.029).

CONCLUSIONS

Postinterventional subarachnoid hyperdensities are a frequent finding after MT and are associated with neurological decline and worse functional outcome. They are more common with distal occlusions and multiple device passes.

Mechanoresponsive Drug Delivery Systems for Vascular Diseases

Mechanoresponsive drug delivery systems (DDS) have emerged as promising candidates to improve the current effectiveness and lower the side effects typically associated with direct drug administration in the context of vascular diseases. Despite tremendous research efforts to date, designing drug delivery systems able to respond to mechanical stimuli to potentially treat these diseases is still in its infancy. By understanding relevant biological forces emerging in healthy and pathological vascular endothelium, it is believed that better-informed design strategies can be deduced for the fabrication of simple-to-complex macromolecular assemblies capable of sensing mechanical forces. These responsive systems are discussed through insights into essential parameter design (composition, size, shape, and aggregation state) , as well as their functionalization with (macro)molecules that are intrinsically mechanoresponsive (e.g., mechanosensitive ion channels and mechanophores). Mechanical forces, including the pathological shear stress and exogenous stimuli (e.g., ultrasound, magnetic fields), used for the activation of mechanoresponsive DDS are also introduced, followed by in vitro and in vivo experimental models used to investigate and validate such novel therapies. Overall, this review aims to propose a fresh perspective through identified challenges and proposed solutions that could be of benefit for the further development of this exciting field.

DEEP MOVEMENT: Deep learning of movie files for management of endovascular thrombectomy

OBJECTIVES

Treatment and outcomes of acute stroke have been revolutionised by mechanical thrombectomy. Deep learning has shown great promise in diagnostics but applications in video and interventional radiology lag behind. We aimed to develop a model that takes as input digital subtraction angiography (DSA) videos and classifies the video according to (1) the presence of large vessel occlusion (LVO), (2) the location of the occlusion, and (3) the efficacy of reperfusion.

METHODS

All patients who underwent DSA for anterior circulation acute ischaemic stroke between 2012 and 2019 were included. Consecutive normal studies were included to balance classes. An external validation (EV) dataset was collected from another institution. The trained model was also used on DSA videos post mechanical thrombectomy to assess thrombectomy efficacy.

RESULTS

In total, 1024 videos comprising 287 patients were included (44 for EV). Occlusion identification was achieved with 100% sensitivity and 91.67% specificity (EV 91.30% and 81.82%). Accuracy of location classification was 71% for ICA, 84% for M1, and 78% for M2 occlusions (EV 73, 25, and 50%). For post-thrombectomy DSA (n = 194), the model identified successful reperfusion with 100%, 88%, and 35% for ICA, M1, and M2 occlusion (EV 89, 88, and 60%). The model could also perform classification of post-intervention videos as mTICI < 3 with an AUC of 0.71.

CONCLUSIONS

Our model can successfully identify normal DSA studies from those with LVO and classify thrombectomy outcome and solve a clinical radiology problem with two temporal elements (dynamic video and pre and post intervention).

KEY POINTS

• DEEP MOVEMENT represents a novel application of a model applied to acute stroke imaging to handle two types of temporal complexity, dynamic video and pre and post intervention. • The model takes as an input digital subtraction angiograms of the anterior cerebral circulation and classifies according to (1) the presence or absence of large vessel occlusion, (2) the location of the occlusion, and (3) the efficacy of thrombectomy. • Potential clinical utility lies in providing decision support via rapid interpretation (pre thrombectomy) and automated objective gradation of thrombectomy outcomes (post thrombectomy).

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

Association of inpatient rehabilitation with functional outcome in patients with stroke receiving mechanical thrombectomy

INTRODUCTION

Patients with ischemic strokes that have undergone mechanical thrombectomy (MT) can still have poor functional outcomes. Limited research exists on factors that impact functional outcomes in these patients who are discharged to inpatient rehabilitation. We examined patient characteristics correlated with 90-day outcomes in ischemic stroke patients having undergone MT and undergo acute rehabilitation.

METHODS

This is a retrospective study of patients (≥18 years) who were consecutively admitted to inpatient rehabilitation after undergoing MT following an ischemic stroke event from 2015 through 2018. Functional outcomes at 90-days were determined by the modified Rankin Score (mRS). Binary logistic regression models were used to measure the association of meaningful Functional Independence Measure (FIM) change with poor-outcome (mRS >2).

RESULTS

Out of 56 stroke patients undergoing MT, 36 had poor outcome (mRS >2) at 90-days. One unit increase in discharge FIM significantly decreased the likelihood of poor outcome by 4% [aOR = 0.96; 95% CI = 95% CI = 0.92, 0.99]. Admission FIM [aOR = 0.95; 95% CI = 0.90, 1.00] and change in FIM [aOR = 0.97; 95% CI = 0.93, 1.02] were not significantly associated poor outcome in the adjusted models.

CONCLUSION

Patients with ischemic stroke who received MT who have a worse disability, particularly at discharge, while undergoing inpatient rehabilitation have higher odds of having poor future functional outcomes. This was regardless of age, sex, or race. Future research is needed to understand the mechanisms that can improve functional performance in our patient population at the IRF.

Association Between Intravenous Thrombolysis and Clinical Outcomes Among Patients With Ischemic Stroke and Unsuccessful Mechanical Reperfusion

Importance

Clinical evidence of the potential treatment benefit of intravenous thrombolysis preceding unsuccessful mechanical thrombectomy (MT) is scarce.

Objective

To determine whether intravenous thrombolysis (IVT) prior to unsuccessful MT improves functional outcomes in patients with acute ischemic stroke.

Design, Setting, and Participants

Patients were enrolled in this retrospective cohort study from the prospective, observational, multicenter German Stroke Registry-Endovascular Treatment between May 1, 2015, and December 31, 2021. This study compared IVT plus MT vs MT alone in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion in whom mechanical reperfusion was unsuccessful. Unsuccessful mechanical reperfusion was defined as failed (final modified Thrombolysis in Cerebral Infarction grade of 0 or 1) or partial (grade 2a). Patients meeting the inclusion criteria were matched by treatment group using 1:1 propensity score matching.

Interventions

Mechanical thrombectomy with or without IVT.

Main Outcomes and Measures

Primary outcome was functional independence at 90 days, defined as a modified Rankin Scale score of 0 to 2. Safety outcomes were the occurrence of symptomatic intracranial hemorrhage and death.

Results

After matching, 746 patients were compared by treatment arms (median age, 78 [IQR, 68-84] years; 438 women [58.7%]). The proportion of patients who were functionally independent at 90 days was 68 of 373 (18.2%) in the IVT plus MT and 42 of 373 (11.3%) in the MT alone group (adjusted odds ratio [AOR], 2.63 [95% CI, 1.41-5.11]; P = .003). There was a shift toward better functional outcomes on the modified Rankin Scale favoring IVT plus MT (adjusted common OR, 1.98 [95% CI, 1.35-2.92]; P < .001). The treatment benefit of IVT was greater in patients with partial reperfusion compared with failed reperfusion. There was no difference in symptomatic intracranial hemorrhages between treatment groups (AOR, 0.71 [95% CI, 0.29-1.81]; P = .45), while the death rate was lower after IVT plus MT (AOR, 0.54 [95% CI, 0.34-0.86]; P = .01).

Conclusions and Relevance

These findings suggest that prior IVT was safe and improved functional outcomes at 90 days. Partial reperfusion was associated with a greater treatment benefit of IVT, indicating a positive interaction between IVT and MT. These results support current guidelines that all eligible patients with stroke should receive IVT before MT and add a new perspective to the debate on noninferiority of combined stroke treatment.

Endovascular thrombectomy in young patients with stroke

BACKGROUND

Endovascular treatment (ET) is standard of care in patients with acute ischemic stroke due to large vessel occlusion, but data on ET in young patients remain limited.

AIM

We aim to compare outcomes for young stroke patients undergoing ET in a matched cohort.

METHODS

We analyzed patients from an observational multicenter cohort with acute ischemic stroke and ET, the German Stroke Registry-Endovascular Treatment trial. Baseline characteristics, procedural parameters, and functional outcome at 90 days were compared between young (<50 years) and older (⩾50 years) patients with and without nearest-neighbor 1:1 propensity score matching.

RESULTS

Out of 6628 acute ischemic stroke patients treated with ET, 363 (5.5%) were young. Young patients differed with regard to prognostic outcome characteristics. Specifically, National Institutes of Health Stroke Scale (NIHSS) at admission was lower (median 13, interquartile range (IQR) 8-17 vs. 15, IQR 9-19, p < 0.001), and prestroke dependence was less frequent (2.9% vs. 12.2%, p < 0.001) than in older patients. Compared to a matched cohort of older patients, ET was faster (time from groin puncture to flow restoration, 35 vs. 45 min, p < 0.001) and intracranial hemorrhage was less frequent in young patients (10.0% vs. 25.9%, p < 0.001). Good functional outcome (modified Rankin Scale (mRS) 0-2) at 3 months was achieved more frequently in young patients (71.6% vs. 44.1%, p < 0.001), and overall mortality was lower (6.7% vs. 25.4%, p < 0.001). Among previously employed young patients (n = 177), 37.9% returned to work at 3-month follow-up, while 74.1% of the remaining patients were still undergoing rehabilitation.

CONCLUSION

Young stroke patients undergoing ET have better outcomes compared to older patients, even when matched for prestroke condition, comorbidities, and stroke severity. Hence, more liberal guidelines to perform ET for younger patients may have to be established by future studies.

Impact of width of susceptibility vessel sign on recanalization following endovascular therapy

BACKGROUND AND PURPOSE

We aimed to investigate the relationship between arterial recanalization following endovascular therapy and the susceptibility vessel sign (SVS) length and width on susceptibility-weighted imaging.

METHODS

We retrospectively evaluated consecutive patients with anterior circulation ischemic stroke who underwent magnetic resonance imaging preceded endovascular therapy, and measured the SVS length and width. Successful recanalization was defined as expanded thrombolysis in cerebral infarction grade of 2b to 3. Logistic regression analysis was executed to determine the independent predictors of successful recanalization and first-pass reperfusion (FPR) after endovascular therapy.

RESULTS

Among 100 patients, successful recanalization and FPR were observed in 77 and 34 patients, respectively. The median SVS length and width were 10.3 mm (interquartile range, 6.8-14.1 mm) and 4.2 mm (interquartile range, 3.1-5.2 mm), respectively. In multivariate logistic regression analysis, SVS width was associated with successful recanalization (odds ratio, 1.88; 95% confidence interval, 1.14-3.07; p = 0.005) and FPR (odds ratio, 1.38; 95% confidence interval, 1.01-1.89; p = 0.039). The optimal cutoff value for the SVS width to predict successful recanalization and FPR were 4.2 mm and 4.0 mm, respectively.

CONCLUSIONS

Larger SVS width may predict successful recanalization and FPR following endovascular therapy.

Outcome of Stroke Patients with Unknown Onset and Unknown Time Last Known Well Undergoing Endovascular Therapy

PURPOSE

Endovascular treatment (ET) in patients with large vessel occlusion stroke (LVOS) with unknown onset or an extended time window can be safe and effective if patients are selected by defined clinical and imaging criteria; however, it is unclear if these criteria should also be applied to patients with unknown onset and unknown time last known well. In this study, we aimed to assess whether absent information on the time patients were last known to be well impacts outcome in patients with unknown onset LVOS.

METHODS

We analyzed patients who were enrolled in the German Stroke Registry-Endovascular Treatment between 2015 and 2019. Patients with unknown onset and unknown time last known well (LKWu) were compared to patients with known onset (KO) and to patients with unknown onset but known time last known well (LKWk) regarding clinical and imaging baseline characteristics and outcome.

RESULTS

Out of 5909 patients, 561 presented with LKWu (9.5%), 1849 with LKWk (31.3%) and 3499 with KO (59.2%). At 90 days, functional independency was less frequent in LKWu (27.0%) compared to KO (42.6%) and LKWk patients (31.8%). These differences were not significant after adjusting for confounders. A main confounder was the initial Alberta stroke program early CT score.

CONCLUSION

The LKWu patients had a similar outcome after ET as KO and LKWk patients after adjusting for confounders. Thus, ET should not be withheld if the time last known well is unknown. Instead, LKWu patients may be selected for ET using the same criteria as in LKWk patients.

Pooled blood volume measured by final flat-panel detector computed tomography predicts outcome after endovascular thrombectomy for acute ischemic stroke

Background

Pooled blood volume (PBV), measured in real-time in the angiography room using an angiography system, correlates with cerebral blood volume (CBV). We examined the usefulness of PBV in endovascular thrombectomy (EVT) for acute ischemic stroke (AIS).

Methods

EVT for AIS in the anterior circulation (internal carotid artery (ICA) and middle cerebral artery (MCA)) was performed in 31 cases (13 males, 18 females, average age 75.7 years). PBV was acquired using a biplane flat-panel detector (FD) angiographic system. Then, we measured the average PBV value in the M1-6 regions similar to the Alberta Stroke Program Early CT score (ASPECTS) before and after EVT. We investigated factors associated with favorable outcome at 90 days after EVT.

Results

There were 13 patients (41.9%) in the good outcome group (mRS (modified Rankin Scale) ≦2) and 18 patients (58.1%) in the poor outcome group (mRS>2). In univariate analysis, NIHSS (National Institutes of Health Stroke Scale) (odds ratio [OR] 0.74, 95% CI 0.57-0.87, p < 0.0001) and post PBV value (odds ratio [OR] 1.13, 95% CI 1.03-1.29, p = 0.0086) were significantly associated with good outcome. The good outcome group had significantly higher post-thrombectomy PBV value (3.69 ± 0.32 ml/100 g versus 2.78 ± 0.93 ml/100 g, P = 0.002) compared to that of the poor outcome group. The relationship between pre-thrombectomy PBV value and outcome at 90 days was not significant.

Conclusions

Post-operative PBV value measured by FD-CT (computed tomography) correlated with 90-day outcome after EVT for AIS. FD-CT-PBV would be one of the good predictors of clinical outcome.

Impact of Time to Treatment on Endovascular Thrombectomy Outcomes in the Early Versus Late Treatment Time Windows

BACKGROUND

The impact of time to treatment on outcomes of endovascular thrombectomy (EVT) especially in patients presenting after 6 hours from symptom onset is not well characterized. We studied the differences in characteristics and treatment timelines of EVT-treated patients participating in the Florida Stroke Registry and aimed to characterize the extent to which time impacts EVT outcomes in the early and late time windows.

METHODS

Prospectively collected data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from January 2010 to April 2020 were reviewed. Participants were EVT patients with onset-to-puncture time (OTP) of ≤24 hours and categorized into early window treated (OTP ≤6 hours) and late window treated (OTP >6 and ≤24 hours). Association between OTP and favorable discharge outcomes (independent ambulation, discharge home and to acute rehabilitation facility) as well as symptomatic intracerebral hemorrhage and in-hospital mortality were examined using multilevel-multivariable analysis with generalized estimating equations.

RESULTS

Among 8002 EVT patients (50.9% women; median age [±SD], 71.5 [±14.5] years; 61.7% White, 17.5% Black, and 21% Hispanic), 34.2% were treated in the late time window. Among all EVT patients, 32.4% were discharged home, 23.5% to rehabilitation facility, 33.7% ambulated independently at discharge, 5.1% had symptomatic intracerebral hemorrhage, and 9.2% died. As compared with the early window, treatment in the late window was associated with lower odds of independent ambulation (odds ratio [OR], 0.78 [0.67-0.90]) and discharge home (OR, 0.71 [0.63-0.80]). For every 60-minute increase in OTP, the odds of independent ambulation reduced by 8% (OR, 0.92 [0.87-0.97]; P<0.001) and 1% (OR, 0.99 [0.97-1.02]; P=0.5) and the odds of discharged home reduced by 10% (OR, 0.90 [0.87-0.93]; P<0.001) and 2% (OR, 0.98 [0.97-1.00]; P=0.11) in the early and late windows, respectively.

CONCLUSIONS

In routine practice, just over one-third of EVT-treated patients independently ambulate at discharge and only half are discharged to home/rehabilitation facility. Increased time from symptom onset to treatment is significantly associated with lower chance of independent ambulation and ability to be discharged home after EVT in the early time window.

Start, Stop, Continue? The Benefit of Overlapping Intravenous Thrombolysis and Mechanical Thrombectomy : A Matched Case-control Analysis from the German Stroke Registry

OBJECTIVE

Here we compare the procedural and clinical outcome of patients undergoing thrombectomy with running thrombolysis to matched controls with completed intravenous therapy and an only marginally overlapping activity.

METHODS

Patients from 25 sites in Germany were included, who presented with an acute ischemic stroke. Patients' baseline characteristics (including ASPECTS, NIHSS and mRS), grade of reperfusion, and functional outcome 24 h and at day 90 after intervention were extracted from the German Stroke Registry (n = 2566). In a case-control design we stepwise matched the groups due to age, sex and time to groin puncture and time to flow restoration.

RESULTS

In the initial cohort (overlap group n = 864, control group n = 1702) reperfusion status (median TICI in overlap group vs. control group: 3 vs. 2b), NIHSS after 24 h, early neurological improvement parameters, mRS at 24 h and at day 90 were significantly better in the overlap group (p < 0.001) with a similar risk of bleeding (2.9% vs. 2.4%) and death (18% vs. 22%). After adjustment mRS at day 90 still showed a trend for lower disability scores in the overlap group (3 IQR 1-5 vs. 3 IQR 1-6, p = 0.09). While comparable bleeding risk could be maintained (4% in both groups), there were significantly more deaths in the control group (18% vs. 30%, p = 0.006).

CONCLUSION

The presented results support the approach of continuing and completing a simultaneous administration of intravenous thrombolysis during mechanical thrombectomy procedures.