Endovascular treatment in anterior circulation stroke beyond 6.5 hours after onset or time last seen well:results from the MR CLEAN Registry

BACKGROUND: Randomised controlled trials with perfusion selection have shown benefit of endovascular treatment (EVT) for ischaemic stroke between 6 and 24 hours after symptom onset or time last seen well. However, outcomes after EVT in these late window patients without perfusion imaging are largely unknown. We assessed their characteristics and outcomes in routine clinical practice. METHODS: The Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry, a prospective, multicentre study in the Netherlands, included patients with an anterior circulation occlusion who underwent EVT between 2014 and 2017. CT perfusion was no standard imaging modality. We used adjusted ordinal logistic regression analysis to compare patients treated within versus beyond 6.5 hours after propensity score matching on age, prestroke modified Rankin Scale (mRS), National Institutes of Health Stroke Scale, Alberta Stroke Programme Early CT Score (ASPECTS), collateral status, location of occlusion and treatment with intravenous thrombolysis. Outcomes included 3-month mRS score, functional independence (defined as mRS 0–2), and death. RESULTS: Of 3264 patients who underwent EVT, 106 (3.2%) were treated beyond 6.5 hours (median 8.5, IQR 6.9–10.6), of whom 93 (87.7%) had unknown time of stroke onset. CT perfusion was not performed in 87/106 (80.2%) late window patients. Late window patients were younger (mean 67 vs 70 years, p<0.04) and had slightly lower ASPECTS (median 8 vs 9, p<0.01), but better collateral status (collateral score 2–3: 68.3% vs 57.7%, p=0.03). No differences were observed in proportions of functional independence (43.3% vs 40.5%, p=0.57) or death (24.0% vs 28.9%, p=0.28). After matching, outcomes remained similar (adjusted common OR for 1 point improvement in mRS 1.04, 95% CI 0.56 to 1.93). CONCLUSIONS: Without the use of CT perfusion selection criteria, EVT in the 6.5–24-hour time window was not associated with poorer outcome in selected patients with favourable clinical and CT/CT angiography characteristics. randomised controlled trials with lenient inclusion criteria are needed to identify more patients who can benefit from EVT in the late window

Observer variability of absolute and relative thrombus density measurements in patients with acute ischemic stroke

Introduction: Thrombus density may be a predictor for acute ischemic stroke treatment success. However, only limited data on observer variability for thrombus density measurements exist. This study assesses the variability and bias of four common thrombus density measurement methods by expert and non-expert observers. Methods: For 132 consecutive patients with acute ischemic stroke, three experts and two trained observers determined thrombus density by placing three standardized regions of interest (ROIs) in the thrombus and corresponding contralateral arterial segment. Subsequently, absolute and relative thrombus densities were determined using either one or three ROIs. Intraclass correlation coefficient (ICC) was determined, and Bland–Altman analysis was performed to evaluate interobserver and intermethod agreement. Accuracy of the trained observer was evaluated with a reference expert observer using the same statistical analysis. Results: The highest interobserver agreement was obtained for absolute thrombus measurements using three ROIs (ICCs ranging from 0.54 to 0.91). In general, interobserver agreement was lower for relative measurements, and for using one instead of three ROIs. Interobserver agreement of trained non-experts and experts was similar. Accuracy of the trained observer measurements was comparable to the expert interobserver agreement and was better for absolute measurements and with three ROIs. The agreement between the one ROI and three ROI methods was good. Conclusion: Absolute thrombus density measurement has superior interobserver agreement compared to relative density measurement. Interobserver variation is smaller when multiple ROIs are used. Trained non-expert observers can accurately and reproducibly assess absolute thrombus densities using three ROIs

Acute Endovascular Treatment of Patients With lschemic Stroke From Intracranial Large Vessel Occlusion and Extracranial Carotid Dissection

Introduction: Carotid artery dissection (CAD) and atherosclerotic carotid artery occlusion (ACAO) are major causes of a tandem occlusion in patients with intracranial large vessel occlusion (LVO). Presence of tandem occlusions may hamper intracranial access and potentially increases the risk of procedural complications of endovascular treatment (EVT). Our aim was to assess neurological, functional and technical outcome and complications of EVT for intracranial LVO in patients with CAD in comparison to patients with ACAO and to patients without CAD or ACAO. Methods: We analyzed data of the MR CLEAN trial intervention arm and MR CLEAN Registry, acquired in 16 Dutch EVT-centers. Primary outcome was the change in stroke severity by comparing the National Institute of Health Stroke Scale (NIHSS) score at 24-48 h after treatment vs. baseline. Secondary outcomes included reperfusion rate and symptomatic intracranial hemorrhage (sICH). We compared outcomes and complications between patients with CAD vs. patients with ACAO and patients without CAD or ACAO. Results: In total, we identified 74 (4.7%) patients with CAD, 92 (5.9%) patients with ACAO and 1398 (89.4%) patients without CAD or ACAO. Neurological improvement at short-term after EVT in patients with CAD was significantly better compared to ACAO (raw mean -5 vs. mean -1 NIHSS point; p = 0.03) and did not differ compared to patients without CAD or ACAO (-4 NIHSS points; p = 0.62). Rates of successful reperfusion in patients with CAD (47%) was comparable to patients with ACAO (47%; p = 1.00), but was less often achieved compared to patients without CAD or ACAO (58%; p = 0.08). Occurrence of sICH did not differ significantly between CAD patients (5%) and ACAO (11%; p = 0.33) or without CAD/ACAO (6%; p = 1.00). Conclusion: EVT in patients with intracranial LVO due to CAD results in neurological improvement comparable to patients without tandem occlusions. Therefore, carotid artery dissection by itself should not be a contraindication for endovascular treatment in stroke patients with intracranial large vessel occlusion. Although more challenging endovascular procedures are to be suspected in both patients with CAD or ACAO, accurate distinction between CAD and ACAO might influence clinical decision making as better clinical outcome can be expected in patients with CAD

Emergence of surfactant-​free micelles from ternary solutions

Curious effects ranging from enzyme activity to anomalies in evapn. rates that have been known for over fifty years suggest the existence and thermodn. stability of surfactant-free micelles. Only recently, joint X-ray, light and neutron scattering expts. have demonstrated that aggregates and bulk pseudo-phases coexist in presumably normal solns., in which a water insol. component is solubilized in a certain domain of concn. of a hydrotrope component like ethanol. Nevertheless, nothing is known about the mol.-level shape and structure of such aggregates. In this work we characterize mixts. of octanol, ethanol, and water by mol. dynamics simulations. For compns. in the "pre-ouzo" region (close to the single phase stability limit) we observe micelle-like aggregates that are clearly distinct from simple crit. d. fluctuations. We define an ethanol partition in the pseudo-phase from an integral of the van der Waals dispersion energy term. From this partition, octanol-rich aggregates swollen with ethanol appear with an emerging interface. Ethanol is present in the water pseudo-phase with an exponential decay similar to the one predicted by Marcelja and Radic forty years ago

Workflow Intervals of Endovascular Acute Stroke Therapy During On- Versus Off-Hours The MR CLEAN Registry

Background and Purpose-Endovascular treatment (EVT) of patients with acute ischemic stroke because of large vessel occlusion involves complicated logistics, which may cause a delay in treatment initiation during off-hours. This might lead to a worse functional outcome. We compared workflow intervals between endovascular treatment-treated patients presenting during off- and on-hours. Methods-We retrospectively analyzed data from the MR CLEAN Registry, a prospective, multicenter, observational study in the Netherlands and included patients with an anterior circulation large vessel occlusion who presented between March 2014 and June 2016. Off-hours were defined as presentation on Monday to Friday between 17:00 and 08:00 hours, weekends (Friday 17:00 to Monday 8:00) and national holidays. Primary end point was first door to groin time. Secondary end points were functional outcome at 90 days (modified Rankin Scale) and workflow time intervals. We stratified for transfer status, adjusted for prognostic factors, and used linear and ordinal regression models. Results-We included 1488 patients of which 936 (62.9%) presented during off-hours. Median first door to groin time was 140 minutes (95% CI, 110-182) during off-hours and 121 minutes (95% CI, 85-157) during on-hours. Adjusted first door to groin time was 14.6 minutes (95% CI, 9.3-20.0) longer during off-hours. Door to needle times for intravenous therapy were slightly longer (3.5 minutes, 95% CI, 0.7-6.3) during off-hours. Groin puncture to reperfusion times did not differ between groups. For transferred patients, the delay within the intervention center was 5.0 minutes (95% CI, 0.5-9.6) longer. There was no significant difference in functional outcome between patients presenting during off- and on-hours (adjusted odds ratio, 0.92; 95% CI, 0.74-1.14). Reperfusion rates and complication rates were similar. Conclusions-Presentation during off-hours is associated with a slight delay in start of endovascular treatment in patients with acute ischemic stroke. This treatment delay did not translate into worse functional outcome or increased complication rates

Balloon Guide Catheter in Endovascular Treatment for Acute Ischemic Stroke: Results from the MR CLEAN Registry

Purpose: To compare outcomes after endovascular treatment (EVT) for acute ischemic stroke with and without the use of a balloon guide catheter (BGC) in clinical practice. Materials and Methods: Data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN) Registry were used, in which all patients who underwent EVT for anterior-circulation stroke in The Netherlands between 2014 and 2016 were enrolled. Primary outcome was modified Rankin scale (mRS) score at 90 days. Secondary outcomes included reperfusion grade (extended Thrombolysis In Cerebral Infarction [eTICI] score) and National Institutes of Health Stroke Scale (NIHSS) score 24–48 hours after intervention. The association between the use of a BGC and outcomes was estimated with logistic regression adjusted for age, sex, prestroke mRS score, NIHSS score, collateral grade, and time from onset to EVT. Results: A total of 887 patients were included. Thrombectomy was performed with the use of a BGC in 528 patients (60%) and without in 359 patients (40%). There was no significant association between use of a BGC and a shift on the mRS toward better outcome (adjusted common odds ratio, 1.17; 95% confidence interval [CI], 0.91–1.52). Use of a BGC was associated with higher eTICI score (adjusted common OR, 1.33; 95% CI, 1.04–1.70) and improvement of ≥ 4 points on the NIHSS (adjusted OR, 1.40; 95% CI, 1.04–1.88). Conclusions: In clinical practice, use of a BGC was associated with higher reperfusion grade and early improvement of neurologic deficits, but had no positive effect on long-term functional outcome

Admission Glucose and Effect of Intra-Arterial Treatment in Patients With Acute Ischemic Stroke

Hyperglycemia on admission is common after ischemic stroke. It is associated with unfavorable outcome after treatment with intravenous thrombolysis and after intra-arterial treatment. Whether hyperglycemia influences the effect of reperfusion treatment is unknown. We assessed whether increased admission serum glucose modifies the effect of intra-arterial treatment in patients with acute ischemic stroke. We used data from the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). Hyperglycemia was defined as admission serum glucose >7.8 mmol/L. The primary outcome measure was the adjusted common odds ratio for a shift in the direction of a better outcome on the modified Rankin Scale at 90 days, estimated with ordinal logistic regression. Secondary outcome variable was symptomatic intracranial hemorrhage. We assessed treatment effect modification of hyperglycemia and admission serum glucose levels with multiplicative interaction factors and adjusted for prognostic variables. Four hundred eighty-seven patients were included. Mean admission serum glucose was 7.2 mmol/L (SD, 2.2). Fifty-seven of 226 patients (25%) randomized to intra-arterial treatment were hyperglycemic compared with 61 of 261 patients (23%) in the control group. The interaction of either hyperglycemia or admission serum glucose levels and treatment effect on modified Rankin Scale scores was not significant (P=0.67 and P=0.87, respectively). The same applied for occurrence of symptomatic hemorrhage (P=0.39 for hyperglycemia, P=0.39 for admission serum glucose). We found no evidence for effect modification of intra-arterial treatment by admission serum glucose in patients with acute ischemic stroke. URL: www.isrctn.com. Unique identifier: ISRCTN1088875

Safety and Outcome of Endovascular Treatment in Prestroke-Dependent Patients Results From MR CLEAN Registry

Background and Purpose- Prestroke dependence is an exclusion criterion in most trials of endovascular treatment (EVT) for acute ischemic stroke. Little is known about outcomes after EVT in these patients. We compared outcome and safety of EVT between prestroke-dependent and prestroke-independent patients. Methods- We report patients with an anterior circulation occlusion who were included between March 2014 and June 2016 in the MR CLEAN registry (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke)-a prospective, multicenter, observational study for stroke intervention centers in the Netherlands. Prestroke dependence was defined as modified Rankin Scale score of 3 to 5 before onset of current stroke. Primary outcome was favorable outcome at 90 days, defined as modified Rankin Scale of 0 to 2 or not worsening of the modified Rankin Scale score. Secondary outcomes included National Institutes of Health Stroke Scale score post-intervention, reperfusion grade, and safety outcomes. Logistic regression analyses (adjusted for age, baseline National Institutes of Health Stroke Scale score, collaterals, time to EVT, and intravenous thrombolysis before EVT) were used to assess the association between prestroke dependence and outcomes. Results- One thousand four hundred forty-one patients were included in the present study, of whom 157 (11%) were prestroke dependent. Favorable outcome was seen in 27% prestroke-dependent patients, compared with 42% prestroke-independent patients ( P<0.05). After adjustment, prestroke dependence was not associated with less-favorable outcome (ORadjusted, 0.90; 95% CI, 0.58-1.39). The occurrence of symptomatic intracranial hemorrhage and ischemic stroke progression was similar in both groups. Conclusions- A substantial proportion of prestroke-dependent patients will reach prestroke modified Rankin Scale scores after EVT, and complication rates are comparable with prestroke-independent patients. Therefore, prestroke-dependent patients should not be routinely excluded from EVT