Rescue Stent Placement for Acute Ischemic Stroke with Large Vessel Occlusion Refractory to Mechanical Thrombectomy: A Multiethnic Middle Eastern/African/Asian Cohort

PURPOSE

To investigate the safety and effectiveness of rescue stent placement in patients who experienced acute stroke in whom mechanical thrombectomy failed.

METHODS

This was a retrospective review of a multiethnic stroke database. After stent placement, an aggressive antiplatelet protocol was followed with glycoprotein IIb/IIIa infusion. The primary outcomes were incidence of intracerebral hemorrhage (ICH), recanalization score, and favorable prognosis (modified Rankin score ≤ 2) at 90 days. A comparison was made between patients from the Middle East and North Africa (MENA) region and those from other regions.

RESULTS

Fifty-five patients were included, with 87% being men. The mean age was 51.3 years (SD ±11.8); 32 patients (58%) were from South Asia, 12 (22%) from MENA, 9 (16%) from Southeast Asia, and 2 (4%) from elsewhere. Successful recanalization (modified Thrombolysis in Cerebral Infarction score = 2b/3) was achieved in 43 patients (78%), and symptomatic ICH occurred in 2 patients (4%). A favorable outcome at 90 days was seen in 26 of the 55 patients (47%). Apart from significantly older age-mean, 62.8 years (SD ±13; median, 69 years) versus 48.1 years (SD ±9.3; median, 49 years)-and coronary artery disease burden-4 (33%) versus 1 (2%) (P < .05), patients from MENA had risk factors, stroke severity, recanalization rates, ICH rates, and 90-day outcomes similar to those from South and Southeast Asia.

CONCLUSION

Rescue stent placement showed good outcomes and a low risk of clinically significant bleeding in a multiethnic cohort of patients from MENA and South and Southeast Asia, similar to that in published literature.

The Need for Structured Strategies to Improve Stroke Care in a Rural Telestroke Network in Northern New South Wales, Australia: An Observational Study

Introduction: A telestroke network in Northern New South Wales, Australia has been developed since 2017. We theorized that the telestroke network development would drive a progressive improvement in stroke care metrics over time.

Aim: This study aimed to describe changes in acute stroke workflow metrics over time to determine whether they improved with network experience.

Methods: We prospectively collected data of patients assessed by telestroke who received multimodal computed tomography (mCT) and were diagnosed with ischemic stroke or transient ischemic attack from January 2017 to July 2019. The period was divided into two phases (phase 1: January 2017 – October 2018 and phase 2: November 2018 – July 2019). We compared median door-to-call, door-to-image, and door-to-decision time between the two phases.

Results: We included 433 patients (243 in phase 1 and 190 in phase 2). Each spoke site treated 1.5–5.2 patients per month. There were Door-to-call time (median 39 in phase 1, 35 min in phase 2, p = 0.18), and door-to-decision time (median 81.5 vs. 83 min, p = 0.31) were not improved significantly. Similarly, in the reperfusion therapy subgroup, door-to-call time (median 29 vs. 24.5 min, p = 0.12) and door-to-decision time (median 70.5 vs. 67.5 min, p = 0.75) remained substantially unchanged. Regression analysis showed no association between time in the network and door-to-decision time (coefficient 1.5, p = 0.32).

Conclusion: In our telestroke network, acute stroke timing metrics did not improve over time. There is the need for targeted education and training focusing on both stroke reperfusion competencies and the technical aspects of telestroke in areas with limited workforce and high turnover.

Medical Management vs Mechanical Thrombectomy for Mild Strokes: An International Multicenter Study and Systematic Review and Meta-analysis

Importance

The benefit of mechanical thrombectomy (MT) in patients with stroke presenting with mild deficits (National Institutes of Health Stroke Scale [NIHSS] score <6) owing to emergency large-vessel occlusion (ELVO) remains uncertain.

Objective

To assess the outcomes of patients with mild-deficits ELVO (mELVO) treated with MT vs best medical management (bMM).

Data Sources

We retrospectively pooled patients with mELVO during a 5-year period from 16 centers. A meta-analysis of studies reporting efficacy and safety outcomes with MT or bMM among patients with mELVO was also conducted. Data were analyzed between 2013 and 2017.

Study Selection

We identified studies that enrolled patients with stroke (within 24 hours of symptom onset) with mELVO treated with MT or bMM.

Main Outcomes and Measures

Efficacy outcomes included 3-month favorable functional outcome and 3-month functional independence that were defined as modified Rankin Scale scores of 0 to 1 and 0 to 2, respectively. Safety outcomes included 3-month mortality and symptomatic and asymptomatic intracranial hemorrhage (ICH).

Results

We evaluated a total of 251 patients with mELVO who were treated with MT (n = 138; 65 women; mean age, 65.2 years; median NIHSS score, 4; interquartile range [IQR], 3-5) or bMM (n = 113; 51 women; mean age, 64.8; median NIHSS score, 3; interquartile range [IQR], 2-4). The rate of asymptomatic ICH was lower in bMM (4.6% vs 17.5%; P = .002), while the rate of 3-month FI (after imputation of missing follow-up evaluations) was lower in MT (77.4% vs 88.5%; P = .02). The 2 groups did not differ in any other efficacy or safety outcomes. In multivariable analyses, MT was associated with higher odds of asymptomatic ICH (odds ratio [OR], 11.07; 95% CI, 1.31-93.53; P = .03). In the meta-analysis of 4 studies (843 patients), MT was associated with higher odds of symptomatic ICH in unadjusted analyses (OR, 5.52; 95% CI, 1.91-15.49; P = .002; I2 = 0%). This association did not retain its significance in adjusted analyses including 2 studies (OR, 2.06; 95% CI, 0.49-8.63; P = .32; I2 = 0%). The meta-analysis did not document any other independent associations between treatment groups and safety or efficacy outcomes.

Conclusions and Relevance

Our multicenter study coupled with the meta-analysis suggests similar outcomes of MT and bMM in patients with stroke with mELVO, but no conclusions about treatment effect can be made. The clinical equipoise can further be resolved by a randomized clinical trial.

Air vs. Road Decision for Endovascular Clot Retrieval in a Rural Telestroke Network

Background and Purpose: Telestroke aims to increase access to endovascular clot retrieval (ECR) for rural areas. There is limited information on transfer workflow for ECR in rural settings. We sought to describe the transfer metrics for ECR in a rural telestroke network with respect to decision making.

Methods: A retrospective cohort study was employed on consecutive patients transferred to the comprehensive stroke center (CSC) for ECR in a rural hub-and-spoke telestroke network between April 2013 and October 2019, by road or air. Key time-based metrics were analyzed.

Results: Sixty-two patients were included. Mean age was 66 years [standard deviation (SD), 14] and median National Institutes of Health Stroke Scale 13 [interquartile range (IQR), 8–18]. Median rural-hospital-door-to-CSC-door (D2D) was 308 min (IQR, 254–351), of which 68% was spent at rural hospitals [door-in-door-out (DIDO); 214 min; IQR, 171–247]. DIDO was longer for air transfers than road (P = 0.004), primarily because of a median 87 min greater decision-to-departure time (Decision-DO, P < 0.001). In multiple linear regression analysis, intubation but not thrombolysis was associated with significantly longer DIDO. The distance at which the extra speed of an aircraft made up for the delays involved in booking an aircraft was 299 km from the CSC.

Conclusions: DIDO is longer for air retrievals compared with road. Decision-DO represents the most important component of DIDO, being longer for air transfers. Systems for rapid transportation of rural ECR candidates need optimization for best patient outcomes, with decision support seen as a potential tool to achieve this.

Intravenous thrombolysis for large vessel or distal occlusions presenting with mild stroke severity

BACKGROUND AND PURPOSE

We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points.

METHODS

The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding.

RESULTS

We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy.

CONCLUSIONS

Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.

No Evidence of the "Weekend Effect" in the Northern New South Wales Telestroke Network

Background: Admission outside normal business hours has been associated with prolonged door-to-treatment times and poorer patient outcomes, the so called "weekend effect. " This is the first examination of the weekend effect in a telestroke service that uses multi-modal computed tomography. Aims: To examine differences in workflow and triage between in-hours and out-of-hours calls to a telestroke service. Methods: All patients assessed using the Northern New South Wales (N-NSW) telestroke service from April 2013 to January 2019 were eligible for inclusion (674 in total; 539 with complete data). The primary outcomes measured were differences between in-hours and out-of-hours in door-to-call-to-decision-to-needle times, differences in the proportion of patients confirmed to have strokes or of patients selected for reperfusion therapies or patients with a modified Rankin Score (mRS ≤ 2) at 90 days. Results: There were no significant differences between in-hours and out-of-hours in any of the measured times, nor in the proportions of patients confirmed to have strokes (67.6 and 69.6%, respectively, p = 0.93); selected for reperfusion therapies (22.7 and 22.6%, respectively, p = 0.56); or independent at 3 months (34.8 and 33.6%, respectively, p = 0.770). There were significant differences in times between individual hospitals, and patient presentation more than 4.5 h after symptom onset was associated with slower times (21 minute delay in door-to-call, p = 0.002 and 22 min delay in door-to-image, p = 0.001). Conclusions: The weekend effect is not evident in the Northern NSW telestroke network experience, though this study did identify some opportunities for improvement in the delivery of acute stroke therapies.

Baseline Occlusion Angiographic Appearance on Mechanical Thrombectomy Suggests Underlying Etiology and Outcome

Background: Etiology of a large vessel occlusion is relevant in the management of acute ischemic stroke patients and often difficult to determine in the acute phase.

Aims: We aim to investigate whether the angiographic appearance of the occlusion is related to its etiology and outcome.

Materials and Methods: Patients without cervical carotid occlusions who underwent mechanical thrombectomy in our center from April 2015 to September 2018 were studied. Demographics, clinical and radiological variables and outcome measures, including etiological classification of stroke, were collected. Underlying intracranial atherosclerosis was estimated according to the presence of stenosis after recanalization. Patients were assigned to groups based on the appearance of the occlusion observed in the first angiogram as “tapered” or “non-tapered.” Differences were searched amongst them.

Results: 131 patients met inclusion criteria. 31 (23.6%) were “tapered” and 100 (76.3%) non-tapered. Tapered presented lower mean baseline NIHSS (10.3 ± 6.2 vs. 16.1 ± 7.2; p < 0.001), smaller acute infarct cores as CTP CBV ASPECTS (8.6 ± 1.6 vs. 7.2 ± 2.4; p = 0.003), higher proportion of instant re-occlusions (26.7 vs. 8.2%; p = 0.025), fewer complete recanalization (45.2 vs. 71.0%; p = 0.028), and more persistent occlusions (37.5 vs. 10.6%; p = 0.011) on follow up MRA. There were no differences in reperfusion rates (83.9 vs. 84.0%; p = 0.986) nor in good long term functional outcome (50.0 vs. 51.1%; p = 0.921). Intracranial atherosclerosis etiology was more common in tapered than in non-tapered occlusions (54.8 vs. 18.0%; p < 0.001).

Conclusion: The angiographic appearance of an occlusion in mechanical thrombectomy patients may determine its etiology, predict likelihood of successful recanalization, and risk of reocclusion.

The Impact of Diabetes on Outcomes After Acute Ischemic Stroke: A Prospective Observational Study

BACKGROUND

Stroke in diabetics may delay recovery and increases the risk of early recurrence of stroke. We compared the outcomes of patients (with and without diabetes) admitted with an acute ischemic stroke (AIS) in the state of Qatar.

PATIENTS AND METHODS

We prospectively compared the clinical presentation, complications, discharge outcome, and stroke recurrence at 90 days in patients with and without diabetes.

RESULTS

Five thousand two hundred twenty-eight stroke patients were admitted between January 2014 and December 2017. Two thousand nine hundred sixty-one had confirmed AIS, 1695 (57.2%) had diabetes, 429 (14.5%) had prediabetes and 873 (29.5%) had no diabetes. Comparing diabetic patients to prediabetic and nondiabetics, they were significantly older (58.5 ± 11.9 versus 54.0 ± 12.9 versus 49.5 ± 13.8, P = .0001), had higher rates of hypertension (80.8% versus 67.4% versus 59.2%), previous stroke (18.0% versus 5.4% versus 6.2%), and coronary artery disease (12.9% versus 5.6% versus 5.0%; P = .001 for all). The percentage of patients with modified Rankin scale 3-6 at discharge (39.7% versus 32.6% versus 30.2%; P = .0001) and 90 days (26.7% versus 18.8% versus 21.4%, P = .001); 90-day mortality (6.2% versus 2.2% versus 5.2%; P = .03) and stroke recurrence (4.2% versus .7% versus 2.2%; P = .005) was significantly higher in diabetic patients.

CONCLUSIONS

Patients with diabetes and AIS have more in-hospital complications, worse discharge outcomes, higher mortality and stroke recurrence at 90 days, compared to prediabetes and no diabetes.

Evaluation of hyperacute infarct volume using ASPECTS and brain CT perfusion core volume

OBJECTIVE

To compare the accuracy of Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and CT perfusion to detect established infarction in acute anterior circulation stroke.

METHODS

We performed an observational study in 59 acute anterior circulation ischemic stroke patients who underwent brain noncontrast CT, CT perfusion, and MRI within 100 minutes from CT imaging. ASPECTS scores were calculated by 4 blinded vascular neurologists. The accuracy of ASPECTS and CT perfusion core volume to detect an acute MRI diffusion lesion of ≥70 mL was evaluated using receiver operating characteristics analysis and optimum cutoff values were calculated using Youden J.

RESULTS

Median ASPECTS score was 8 (interquartile range [IQR] 5-9). Median CT perfusion core volume was 22 mL (IQR 10.4-71.9). Median MRI diffusion lesion volume was 24.5 mL (IQR 10-63.9). No significant difference was found between the accuracy of CT perfusion and ASPECTS (c statistic 0.95 vs 0.87, p value for difference = 0.17). The optimum ASPECTS cutoff score to detect a diffusion-weighted imaging lesion ≥70 mL was <7 (sensitivity 0.74, specificity 0.86, Youden J = 0.60) and the optimum CT perfusion core volume cutoff was ≥50 mL (sensitivity 0.86, specificity 0.97, Youden J = 0.84). The CT perfusion core lesion covered a median of 100% (IQR 86%-100%) of the acute MRI lesion volume (Pearson R = 0.88; R² = 0.77).

CONCLUSIONS

We found no significant difference between the accuracy of CT perfusion and ASPECTS to predict hyperacute MRI lesion volume in ischemic stroke.

Abstract 38: Brain CT Perfusion is Superior to Non-contrast CT Aspects in the Evaluation of Hyperacute Infarct Volume

Objective: To compare the predictive capacity to detect established infarct in acute anterior circulation stroke between the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on non-contrast computed tomography (CT) and CT perfusion.

Methods: Fifty-nine acute anterior circulation ischemic stroke patients received brain non-contrast CT, CT perfusion and hyperacute magnetic resonance imaging (MRI) within 100 minutes from CT imaging. ASPECTS scores were calculated by 4 independent vascular neurologists, blinded from CT perfusion and MRI data. CT perfusion infarct core volumes were calculated by MIStar software. The accuracy of commonly used ASPECTS cut-off scores and a CT perfusion core volume of ≥ 70 mL to detect a hyperacute MRI diffusion lesion of ≥ 70 ml was evaluated.

Results: Median ASPECTS score was 9 (IQR 7-10). Median CT perfusion core volume was 22 ml (IQR 10.4-71.9). Median MRI diffusion lesion volume was 24,5 ml (IQR 10-63.9). ASPECTS score of < 6 had a sensitivity of 0.37, specificity of 0.95 and c-statistic of 0.66 to predict an acute MRI lesion ≥ 70 ml. In comparison, a CT perfusion core lesion of ≥ 70 ml had a sensitivity of 0.76, specificity of 0.98 and c-statistic of 0.92. The CT perfusion core lesion covered a median of 100% of the acute MRI lesion volume (IQR 86-100%).

Conclusions: CT perfusion is superior to ASPECTS to predict hyperacute MRI lesion volume in ischemic stroke.

Preliminary experience with the Pipeline Flex Embolization Device: technical note

BACKGROUND

Clinical experience with the Pipeline Embolization Device (PED) has been widely described in the literature since it obtained its European CE and FDA approvals in 2008 and 2011, respectively. The new generation of PED, the Pipeline Flex Embolization Device, received the CE mark of approval in March 2014. While the implant composition has not changed, its new delivery system has some differences. One of the main changes from the previous generation is a new delivery system that makes the device resheathable until deployed over 90% of its length. We present our preliminary experience using this device.

METHODS

Between May and June 2014, six patients with six aneurysms were treated with the Pipeline Flex device.

RESULTS

All devices were placed properly, without technical difficulties. We successfully resheathed and repositioned the device in two cases. Minor and major intraprocedural or periprocedural events were noted.

CONCLUSIONS

The Pipeline Flex device allows more precise and controlled deployment than the current PED device. Although this preliminary experience seems positive, multicenter larger series will be needed to confirm the safety and durability of this new device.

[Perfusion computed tomography makes it possible to overcome important SITS-MOST exclusion criteria for the endovenous thrombolysis of cerebral infarction]

AIM. To study the frequency, safety and efficacy of perfusion computed tomography (PCT), through identification of brain tissue-at-risk, to guide intravenous thrombolysis in stroke patients with regulatory exclusion criteria (SITS-MOST and ECASS-3). PATIENTS AND METHODS. We studied consecutive acute non-lacunar ischemic stroke patients. After conventional CT was considered eligible, PCT was performed in the following circumstances: 4.5 to 6 h window, wake-up stroke or unknown time of onset; extent early infarct signs on CT; minor or severe stroke; seizures or loss of consciousness. Intravenous 0.9 mg/kg alteplase was indicated if: cerebral blood volume lesion covered < 1/3 of middle cerebral artery territory; mismatch > 20% between mean transit time and cerebral blood volume maps existed; and informed consent. SITS-MOST safety-efficacy parameters were used as endpoint variables. RESULTS. Between May 2009-April 2010, 66 hyperacute ischemic stroke patients a priori not eligible for intravenous thrombolysis underwent PCT. Indications were: > 4.5 h in 18 patients, wake up stroke or unknown onset in 25, extent infarct signs in 6, seizures at onset in 11, and minor stroke (NIHSS < 4) in 6. Twenty-nine (44%) of them finally received intravenous thrombolysis. Symptomatic hemorrhagic transformation occurred in 2 (6.9%) patient and 18 (62.1%) achieved a modified Rankin scale score equal or less than 2 on day 90. CONCLUSION. A high proportion of acute stroke patients with SITS-MOST and ECASS-3 exclusion criteria can be safely and efficaciously treated with intravenous thrombolysis using a PCT selection protocol. However randomized control trials will be needed to confirm our results.

[Some reflections on the pathophysiology of abnormal movements]

INTRODUCTION

The field of abnormal movements is an area that is in continual expansion within Neurology and treatment is currently available for many of them, at least as far as the symptoms are concerned. Yet, the exact mechanisms of operation of the neurological structures involved in movement are not fully understood.

DEVELOPMENT

It seems clear that the basal ganglia play an important role, fundamentally in pseudo-automatic movements, but because they are interconnected with many other structures it is difficult to gain a precise understanding of their individual functions. There are theories based solely on anatomical data, which are not enough to account for everything. The theory of the existence of neuronal circuits seems to explain a wider part of movement, although it still has a number of shortcomings. Another theory of movement disorders is that based on neurochemistry, according to which the imbalance of certain neurotransmitters would be the causation of the disease, but this theory does not enable us to explain all the pathologies related to movement either. A number of clinical observations and the use of animal models, however, have made it possible to draw up pathophysiological hypotheses about the generation of some abnormal movements.

CONCLUSIONS

All these approaches have enabled researchers to find symptomatic treatments for certain diseases, but our knowledge of the pathophysiology involved is still far from complete and the chances of enhancing the therapeutic capacity available in such cases in the future are therefore immense.