A standardized neurointerventional thrombectomy protocol leads to faster recanalization times

Investigating discharge predictors for stroke patients with active cancer after endovascular therapy

OBJECTIVE

Current cancer diagnosis is not an exclusion from treatment with endovascular therapy (EVT) in patients with acute ischemic stroke (AIS). There are insufficient studies to determine whether outcomes, based on modified Rankin Scale (mRS), differ for cancer and non-cancer patients, and what factors affect a favorable outcome. This study aims to identify predictors of discharge outcome in AIS patients with active cancer who have undergone EVT.

METHODS

This retrospective cohort study included patients (age ≥ 18) admitted from 07/01/2018-10/01/2020 with AIS and treated with EVT. Patients were grouped according to the presence or absence of active cancer diagnosis. Multivariable logistic regression determined independent predictors of favorable outcomes (discharge mRS 0-2) in patients with and without active cancer. The predictive utility of admission National Institutes of Health Stroke Scale (NIHSS) was further explored using receiver operating characteristic (ROC) curve analysis to determine area under the curve (AUC) and optimal cut points for favorable outcomes.

RESULTS

Of 463 patients who received EVT, 10 % had cancer. Patients with cancer had significantly higher rates of hypercoagulation-related stroke mechanisms, prior clots, renal failure, and thromboembolic events during hospitalization (all p < 0.01), compared to patients without cancer. Favorable discharge outcomes did not differ significantly between groups (24 % vs. 35 %, p = 0.13). In patients with cancer after adjustment, admission NIHSS independently predicted favorable discharge outcomes (adjusted odds ratio (AOR): 0.81, 95 % confidence interval (CI) 0.69-0.99, p = 0.01), with a 19 % decrease in odds per 1-unit increase in NIHSS. The optimal threshold for NIHSS was 6, with strong fit (AUC: 0.88, p = 0.002). For non-cancer patients, NIHSS (AOR: 0.91, 95 % CI 0.88-0.93, p < 0.001), age, and diabetes history were independent predictors, with a 9 % decrease in odds per unit increase for NIHSS. The threshold for NIHSS in non-cancer patients was 21, with moderate fit (AUC: 0.77, p < 0.001).

CONCLUSION

Admission NIHSS is an important predictor of favorable discharge outcomes in AIS patients with active cancer treated with EVT. Incorporating NIHSS into risk stratification, alongside patients' medical history, may improve the ability to assess the likelihood of favorable discharge outcomes.

Hybrid CT Angio Suite for Acute Ischemic Stroke: A New Time-Saving Workflow Model?

Objectives: Explore the effect of the introduction of a hybrid CT angio suite on the in-hospital workflow time of patients with acute ischemic stroke. Methods: This was a retrospective observational case-control study. All consecutive patients admitted to our emergency department with suspected ischemic stroke who underwent stroke imaging and mechanical thrombectomy (MT) in the new hybrid CT angio suite from October 2023 to March 2024 were included in the study. The primary outcome was the evaluation of in-hospital workflow times by the assessment of both the time from hospital admission to the beginning of the endovascular treatment (door-to-groin time, DTG) and the time from the interpretation of imaging to arterial puncture (CT-to-groin time, CTTG). The secondary aim was the evaluation of the clinical outcome through the evaluation of the mRS at 3 months. These data were compared to the control group. Results: Between October 2023 and March 2024, 50 consecutive patients with suspected ischemic stroke underwent neuroimaging and MT in the hybrid CT angio suite. We observed a significant reduction of the median DTG time from 71 min to 36 min (p < 0.001) and the median CT-to-groin time from 44 min to 12 min (p < 0.001) compared to the control group. Conclusions: The introduction of the hybrid CT angio suite dedicated to acute ischemic stroke has definitely reduced in-hospital delays, allowing better management of these patients.

Stress hyperglycemia is associated with futile recanalization in patients with anterior large vessel occlusion undergoing mechanical thrombectomy

INTRODUCTION

Mechanical thrombectomy (MT) is the standard treatment for acute ischemic stroke (AIS) due to anterior large vessel occlusion (LVO). Despite successful recanalization, some patients remain disabled after 3 months. Mechanisms that can cause futile recanalization (FR) are still largely unknown. We investigated if stress hyperglycemia might be associated with FR.

PATIENTS AND METHODS

This is a retrospective analysis of consecutive patients with successful recanalization treated in four participating centers between January 2021 and December 2022. According to the modified Rankin scale (mRS) status at 3 months, patients were divided into two groups: FR, if mRS score >2, and useful recanalization (UR), if mRS score ⩽2. Stress hyperglycemia was estimated by the glucose-to-glycated hemoglobin ratio (GAR) index.

RESULTS

A total of 691 subjects were included. At 3 months, 403 patients (58.3%) were included in the FR group, while the remaining 288 patients (41.7%) were included in the UR group. At the multivariate analysis, variables independently associated with FR were the following: age (OR 1.04, 95% CI 1.02-1.06, p < 0.001), GAR index (OR 1.08, 95% CI 1.03-1.14, p = 0.003), NIHSS at admission (OR 1.16, 95% CI 1.11-1.22; p < 0.001), and procedure length (OR 1.01, 95% CI 1.00-1.02; p = 0.009). We observed that the model combining age, GAR index, NIHSS at admission, and procedure length had good predictive accuracy (AUC 0.78, 95% CI 0.74-0.81).

CONCLUSIONS

Stress hyperglycemia predicts FR in patients with successful recanalization after MT. Further studies should explore if managing stress hyperglycemia may reduce futile recanalization. Additionally, we recommend paying close attention to AIS patients with a GAR index greater than 24.8 who exhibit a high risk of FR.

Standardized approach to direct first pass aspiration technique for endovascular thrombectomy: Description and initial experience with CANADAPT

BACKGROUND

Endovascular thrombectomy (EVT) is standard of care for acute ischemic stroke. Stent assisted EVT with aspiration (SOLUMBRA) technique has remained a mainstay approach. There is growing evidence that A Direct Aspiration First Pass Technique (ADAPT) is a safe, efficient and effective approach for EVT, offering several advantages. This study describes and reports initial institutional experience in the use of a standardized scientific based aspiration only technique: CANADAPT.

METHODS

Single center prospective cohort study was performed on consecutive patients treated for large/medium vessel ischemic stroke with CANADAPT. Intravenous thrombolytics were administered according to routine practice, independent of the decision to proceed with EVT. A sequential stepwise aspiration only technique was then applied, CANADAPT, consisting of three maneuvers, A, B and C. The reperfusion success rate, number of passes, use of rescue technique, complication rate and procedural cost were determined.

RESULTS

Twenty-two patients were included in this case series representing M1 (17, 77%), M1/2 (2, 9%), carotid-T (2, 9%) and basilar (1, 5%) occlusions. First pass recanalization was achieved in 11 (50%) of patients. A further four patients had successful reperfusion with a second pass of CANADAPT (total 68% success rate). Only one patient had successful reperfusion with the aspiration catheter at the clot interface (CANADAPT A). All others required some withdrawal of the aspiration catheter for reperfusion (CANADAPT B and C). Seven patients had SOLUMBRA rescue. Of these, five patients (22% of total patients) had further successful reperfusion. Overall median procedural time was 23 min for first recanalization and 30 min for final recanalization. The cost per procedure was $6630 ± 1069 for CANADAPT, and $13,530 ± 2706 for SOLUMBRA techniques.

CONCLUSIONS

CANADAPT represents a standardized scientific-based approach to aspiration only thrombectomy intervention. This initial study demonstrates the safety, efficiency and efficacy of this technique for use in EVT.

Recent developments in pre-hospital and in-hospital triage for endovascular stroke treatment

Triage describes the assignment of resources based on where they can be best used, are most needed, or are most likely to achieve success. Triage is of particular importance in time-critical conditions such as acute ischemic stroke. In this setting, one of the goals of triage is to minimize the delay to endovascular thrombectomy (EVT), without delaying intravenous thrombolysis or other time-critical treatments including patients who cannot benefit from EVT. EVT triage is highly context-specific, and depends on availability of financial resources, staff resources, local infrastructure, and geography. Furthermore, the EVT triage landscape is constantly changing, as EVT indications evolve and new neuroimaging methods, EVT technologies, and adjunctive medical treatments are developed and refined. This review provides an overview of recent developments in EVT triage at both the pre-hospital and in-hospital stages. We discuss pre-hospital large vessel occlusion detection tools, transport paradigms, in-hospital workflows, acute stroke neuroimaging protocols, and angiography suite workflows. The most important factor in EVT triage, however, is teamwork. Irrespective of any new technology, EVT triage will only reach optimal performance if all team members, including paramedics, nurses, technologists, emergency physicians, neurologists, radiologists, neurosurgeons, and anesthesiologists, are involved and engaged. Thus, building sustainable relationships through continuous efforts and hands-on training forms an integral part in ensuring rapid and efficient EVT triage.

Viz.ai Implementation of Stroke Augmented Intelligence and Communications Platform to Improve Indicators and Outcomes for a Comprehensive Stroke Center and Network

BACKGROUND AND PURPOSE

Comprehensive stroke centers continually strive to narrow neurointerventional time metrics. Although process improvements have been put in place to streamline workflows, complex pathways, disparate imaging locations, and fragmented communications all highlight the need for continued improvement.

MATERIALS AND METHODS

This Quality Improvement Initiative (VISIION) was implemented to assess our transition to the Viz.ai platform for immediate image review and centralized communication and their effect on key performance indicators in our comprehensive stroke center. We compared periods before and following deployment. Sequential patients having undergone stroke thrombectomy were included. Both direct arriving large-vessel occlusion and Brain Emergency Management Initiative telemedicine transfer large-vessel occlusion cases were assessed as were subgroups of OnHours and OffHours. Text messaging thread counts were compared between time periods to assess communications. Mann-Whitney U and Student t tests were used.

RESULTS

Eighty-two neurointerventional cases were analyzed pre vs. post time periods: (DALVO-OnHours 7 versus 7, DALVO-OffHours 10 versus 5, BEMI-OnHours 13 versus 6, BEMI-OffHours 17 versus 17). DALVO-OffHours had a 39% door-to-groin reduction (157 versus 95 minutes, P = .009). DALVO-All showed a 32% reduction (127 versus 86 minutes, P = .006). BEMI-All improved 33% (42 versus 28 minutes, P = .036). Text messaging thread counts improved 30% (39 versus 27, P = .04).

CONCLUSIONS

There was an immediate improvement following Viz.ai implementation for both direct arriving and telemedicine transfer thrombectomy cases. In the greatest opportunity subset (direct arriving large-vessel occlusion-OffHours: direct arriving cases requiring team mobilization off-hours), we noted a 39% improvement. With Viz.ai, we noted that immediate access to images and streamlined communications improved door-to-groin time metrics for thrombectomy. These results have implications for future care processes and can be a model for centers striving to optimize workflow and improve thrombectomy timeliness.

Does Weekends Effect Exist in Asia? Analysis of Endovascular Thrombectomy for Acute Ischemic Stroke in A Medical Center

BACKGROUND

Discussing the quality measurements based on interrupted time series in ischemic stroke, delays are often attributed to weekends effect. This study compared the metrics and outcomes of emergent endovascular thrombectomy (EST) during working hours versus non-working hours in the emergency department of an Asian medical center.

METHODS

A total of 297 patients who underwent EST between January 2015 and December 2018 were retrospectively included, with 52.5% of patients presenting during working hours and 47.5% presenting during nights, weekends, or holidays.

RESULTS

Patients with diabetes were more in non-working hours than in working hours (53.9% vs. 41.0%; p=0.026). It took longer during nonworking hours than working hours in door-to -image times (13 min vs. 12 min; p=0.04) and door-to-groin puncture times (median: 112 min vs. 104 min; p=0.042). Significant statistical differences were not observed between the two groups in neurological outcomes, including successful reperfusion and complications such as intracranial hemorrhage and mortality. However, the change in National Institute of Health Stroke Scale (NIHSS) scores in 24 hours was better in the working-hour group than in the nonworking-hour group (4 vs. 2; p=0.058).

CONCLUSION

This study revealed that nonworking-hour effects truly exist in patients who received EST. Although delays in door-to-groin puncture times were noticed during nonworking hours, significant differences in neurological functions and mortality were not observed between working and non-working hours. Nevertheless, methods to improve the process during non-working hours should be explored in the future.

Optimizing Door-to-Groin Puncture Time: The Mayo Clinic Experience

OBJECTIVES

To provide a better understanding of methods that can be used to improve patient outcomes by reducing the door-to-groin puncture (DTP) time and present the results of a stroke quality improvement project (QIP) conducted by Mayo Clinic Arizona's stroke center.

METHODS

We conducted a systematic literature search of Ovid MEDLINE(R), Ovid EMBASE, Scopus, and Web of Science for studies that evaluated DTP time reduction strategies. Those determined eligible for the purpose of this analysis were assessed for quality. The strategies for DTP time reduction were categorized on the basis of modified Target: Stroke Phase III recommendations and analyzed using a meta-analysis. The Mayo Clinic QIP implemented a single-call activation system to reduce DTP times by decreasing the time from neurosurgery notification to case start.

RESULTS

Fourteen studies were selected for the analysis, consisting of 2277 patients with acute ischemic stroke secondary to large-vessel occlusions. After intervention, all the studies showed a reduction in the DTP time, with the pooled DTP improvement being the standardized mean difference (1.37; 95% confidence interval, 1.20-1.93; τ²=1.09; P<.001). The Mayo Clinic QIP similarly displayed a DTP time reduction, with the DTP time dropping from 125.1 to 82.5 minutes after strategy implementation.

CONCLUSION

Computed tomography flow modifications produced the largest and most consistent reduction in the DTP time. However, the reduction in the DTP time across all the studies suggests that any systematic protocol aimed at reducing the DTP time can produce a beneficial effect. The relative novelty of mechanical thrombectomy and the consequential lack of research call for future investigation into the efficacy of varying DTP time reduction strategies.

The effectiveness of systemic and endovascular intra-arterial thrombectomy protocol for decreasing door-to-recanalization time duration

Objective

Variable treatment strategies and protocols have been applied to reduce time durations in the process of acute stroke management. The aim of this study is to investigate the effectiveness of our intra-arterial thrombectomy (IAT) protocol for decreasing door-to-recanalization time duration and improve successful recanalization.

Methods

A systemic and endovascular protocol included door-to-image, image-to-puncture and puncture-to-recanalization. We retrospectively analyzed the patients of pre- (Sep 2012–Apr 2014) and post-IAT protocol (May 2014–Jul 2018). Univariate analysis was used for the statistical significance according to variable factors (age, gender, the location of occluded vessel, successful recanalization TICI 2b-3). Independent t-test was used to compare the time duration.

Results

Among all 267 patients with acute stroke of anterior circulation, there were 50 and 217 patients with pre- and post-IAT protocol. Age, gender, and the location of occluded vessel have no statistical significance (p＞0.05). In pre- and post-IAT group, successful recanalization was 39 of 50 (78.0%) and 185/217 (85.3%), respectively (p＜0.05). Post-IAT (48.8%, 106/217) group had a higher tendency of good outcome than pre-IAT group (36.0%, 18/50) (p＞0.05). Pre- and post-IAT group showed 61.7±21.4 vs. 25±16.0 (p＜0.05), 102.0±29.8 vs. 82.7±30.4 (min) (p＜0.05), and 79.1±47.5 vs. 58.4±75.3 (p＜0.05) in three steps, respectively.

Conclusions

We suggest that the application of systemic and endovascular IAT protocols showed a significant time reduction for faster recanalization in patients with LVO. To build-up the well-designed IAT protocol through puncture-to-recanalization can be needed to decrease time duration and improve clinical outcome in recanalization therapy in acute stroke patients.

Implementing the SNIS recommendations for neurointerventional emergent care in the setting of COVID-19: impact on stroke metrics and patient outcomes

Background

It is not clear whether the COVID-19 pandemic and subsequent Society of Neurointerventional Surgery (SNIS) recommendations affected hospital stroke metrics.

Methods

This retrospective cohort study compared stroke patients admitted to a comprehensive stroke center during the COVID-19 pandemic April 1 2020 to June 30 2020 (COVID-19) to patients admitted April 1 2019 to June 30 2019. We examined stroke admission volume and acute stroke treatment use.

Results

There were 637 stroke admissions, 52% in 2019 and 48% during COVID-19, with similar median admissions per day (4 vs 3, P=0.21). The proportion of admissions by stroke type was comparable (ischemic, P=0.69; hemorrhagic, P=0.39; transient ischemic stroke, P=0.10). Acute stroke treatment was similar in 2019 to COVID-19: tPA prior to arrival (18% vs, 18%, P=0.89), tPA treatment on arrival (6% vs 7%, P=0.85), and endovascular therapy (endovascular therapy (ET), 22% vs 25%, P=0.54). The door to needle time was also similar, P=0.12, however, the median time from arrival to groin puncture was significantly longer during COVID-19 (38 vs 43 min, P=0.002). A significantly higher proportion of patients receiving ET were intubated during COVID-19 due to SNIS guideline implementation (45% vs 96%, P<0.0001). There were no differences by study period in discharge mRS, P=0.84 or TICI score, P=0.26.

Conclusions

The COVID-19 pandemic did not significantly affect stroke admission volume or acute stroke treatment utilization. Outcomes were not affected by implementing SNIS guidelines. Although there was a statistical increase in time to groin puncture for ET, it was not clinically meaningful. These results suggest hospitals managing patients efficiently can implement practices in response to COVID-19 without impacting outcomes.

In-hospital acute stroke workflow in acute stroke - Systems-based approaches

Clinical outcomes of acute ischaemic stroke patients have significantly improved with the advent of reperfusion therapy. However, time continues to be a critical factor. Reducing treatment delays by improving workflows can improve the efficacy of acute reperfusion therapy. Systems-based approaches have improved in-hospital temporal parameters, maximizing the utility of reperfusion therapies and improving clinical benefit to patients. However, studies aimed at optimizing and hence reducing treatment delays in emergency department (ED) settings are limited. The aim of this article is to discuss existing systems-based approaches to optimize ED acute stroke workflows and its value in reducing treatment delays and identify gaps in existing workflows that need optimization. Identifying gaps in acute stroke workflow, variations in processes and challenges in implementation, in the in-hospital settings, is essential for systems-based interventions to be effective in delivering improved outcomes for patients with acute ischaemic stroke.

Emerging stroke systems of care in Germany

In order to reduce intrahospital times for stroke patients, we have implemented various strategies throughout the last 4 years. Swift restoration of cerebral perfusion is essential for the outcomes of patients with acute ischemic stroke. Endovascular treatment (EVT) has become the standard of care to accomplish this in patients with acute stroke due to large vessel occlusion (LVO). To achieve reperfusion of ischemic brain regions as fast as possible, all in-hospital time delays have to be avoided. Therefore management of patients with acute ischemic stroke was optimized with an interdisciplinary standard operating procedure (SOP). Stroke neurologists, diagnostic as well as interventional neuroradiologists, and anesthesiologists streamlined all necessary processes from patient admission and diagnosis to EVT of eligible patients. In a second step we established a one-stop management of stroke patients, meaning that imaging was acquired with the same angiography suite use for treatment of patients with LVO. In the last section of this chapter we discuss the latest trials on stroke therapy and their implications for our current triage systems and imaging patterns.

Triage and systems of care in stroke

There has been increasing adoption of endovascular stroke treatment in the United States following multiple clinical trials demonstrating superior efficacy. Next steps in enhancing this treatment include an analysis and development of stroke systems of care geared toward efficient delivery of endovascular and comprehensive stroke care. The chapter presents epidemiological data and an overview of the current state of stroke delivery and potential improvements for the future in the light of clinical data.

Enhancing Education to Avoid Complications in Endovascular Treatment of Unruptured Intracranial Aneurysms: A Neurointerventionalist's Perspective

It is of utmost importance to avoid errors and subsequent complications when performing neurointerventional procedures, particularly when treating low-risk conditions such as unruptured intracranial aneurysms. We used endovascular treatment of unruptured intracranial aneurysms as an example and took a survey-based approach in which we reached out to 233 neurointerventionalists. They were asked what they think are the most important points staff should teach their trainees to avoid errors and subsequent complications in endovascular treatment of unruptured intracranial aneurysms. One hundred twenty-one respondents (51.9%) provided answers in the form of free text responses, which were thematically clustered in an affinity diagram and summarized in this Practice Perspectives. The article is primarily intended for neurointerventional radiology fellows and junior staff and will hopefully provide them the opportunity to learn from the mistakes of their more experienced colleagues.

Strategies to reduce the impact of demand for concurrent endovascular thrombectomy

BACKGROUND

The rise in demand for endovascular thrombectomy (EVT) has increased the possibility that multiple patients with acute ischemic stroke may present concurrently and exceed local capacity to provide timely treatment. In this work, we quantitatively compared the efficacy of various strategies to mitigate demand in excess of capacity (DEC).

METHODS

Strategies evaluated included a backup neurointerventional team for 3 hours, 8 hours, or 24 hours per day; a separate pre-intervention imaging team; and a 30% decrease in procedure duration. For each strategy, empirical distributions were used to probabilistically generate arrival time and case duration for 16 000 independent trials repeated across a range of annual case volumes. DEC was calculated from time series representing the number of concurrent cases at each minute of the year for each trial at each case volume.

RESULTS

All strategies decreased DEC compared with baseline. At a representative volume of 250 cases per year, availability of a backup team for 3 hours, 8 hours, and 24 hours per day reduced DEC by 27.0%, 60.3%, and 97.2%, respectively, compared with baseline. Similarly, availability of a pre-intervention imaging team and a 30% decrease in procedure duration reduced DEC by 26.6% and 17.7%, respectively, compared with baseline.

CONCLUSIONS

A backup neurointerventional team, even if available only part time, was an effective strategy for decreasing DEC for EVT. Understanding the actual quantitative benefit of each strategy can facilitate rational cost-benefit analyses underlying the development of efficient and sustainable models of care.

Simultaneous patient presentation for endovascular thrombectomy in acute ischemic stroke

BACKGROUND

Increased demand for endovascular thrombectomy has increased the likelihood of simultaneous patient presentation leading to competing demand for time-critical treatment that could adversely impact patient outcomes. We aimed to quantify the occurrence of simultaneous patient presentation at different patient volumes.

METHODS

Empirical distributions for time of patient presentation and case duration were used to probabilistically generate arrival time and case duration for a set annual patient volume, ranging from 1 to 500 cases per year, for 16 000 independent trials at each volume. Time series were generated for each trial to represent the number of cases being performed at each minute of the year. Time series were used to calculate daily thrombectomy demand, annual concurrent demand, and hourly excess demand.

RESULTS

The patient volumes at which at least one annual occurrence of concurrent demand by two patients was 50% and 97.5% likely were 45 and 101, respectively. The volumes at which at least one annual occurrence of concurrent demand by three patients was 50% and 97.5% likely were 216 and 387, respectively. There was dramatic variation in the occurrence of excess demand by two or more patients throughout the day.

CONCLUSIONS

The occurrence of simultaneous presentation by multiple patients for endovascular thrombectomy varies with annual patient volume and time of day. Understanding these trends and the associated patient impact can inform intelligent strategies at regional and national levels for optimizing patient care within real-world financial and operational constraints.

An interdisciplinary approach to inhospital stroke improves stroke detection and treatment time

BACKGROUND

Inhospital stroke (IHS) is associated with high morbidity and mortality, likely related to multiple factors, including delayed time to recognition, associated comorbidities, and initial care from non-stroke trained providers. We hypothesized that guided revision of a formalized 'stroke code' system can improve diagnosis and time to thrombolysis and thrombectomy.

METHODS

IHS activations occurring at a comprehensive stroke center between 2013 and 2016 were retrospectively analyzed to guide revisions of an established stroke code protocol to improve provider communication and time to imaging, reduce stroke mimic rate, and improve the use of parallel processing. After protocol implementation, we prospectively collected data between 2016 and 2017 for comparison with the pre-implementation group, including diagnostic accuracy and relevant time points (code call to examination, examination to imaging, and imaging to intervention). We report descriptive statistics for comparison of patient characteristics and time metrics (time to imaging and reperfusion after IHS activation). Multivariable regression analysis was performed to identify independent predictors of stroke mimics and time metrics.

RESULTS

There were 136 cases in the pre-implementation group and 69 in the post-implementation group. A reduction in stroke mimics (52% vs 33%, P=0.01) occurred after protocol initiation. Mean time to imaging after stroke code call was 7.6 min shorter (P=0.026) and mean time from imaging to acute reperfusion therapy was 45.7 vs 19.8 min (P=0.05) in the pre- versus the post-implementation group.

CONCLUSION

Revision of an existing IHS protocol was associated with a lower rate of stroke mimics, and a shorter time to intravenous and intra-arterial intervention.

Protocols for Endovascular Stroke Treatment Diminish the Weekend Effect Through Improvements in Off-Hours Care

Introduction: The weekend effect is a well-recognized phenomenon in which patient outcomes worsen for acute strokes presenting outside routine business hours. This is attributed to non-uniform availability of services throughout the week and evenings and, though described for intravenous thrombolysis candidates, is poorly understood for endovascular stroke care. We evaluated the impact of institutional protocols on the weekend effect, and the speed and outcome of endovascular therapy as a function of time of presentation.

Method: This study assesses a prospective observational cohort of 129 consecutive patients. Patients were grouped based on the time of presentation during regular work hours (Monday through Friday, 07:00–19:00 h) vs. off-hours (overnight 19:00–07:00 h and weekends) and assessed for treatment latency and outcome.

Results: Treatment latencies did not depend on the time of presentation. The door to imaging interval was comparable during regular and off-hours (median time 21 vs. 19 min, respectively, p < 0.50). Imaging to groin puncture was comparable (71 vs. 71 min, p < 1.0), as were angiographic and functional outcomes. Additionally, treatment intervals decreased with increased protocol experience; door-to-puncture interval significantly decreased from the first to the fourth quarters of the study period (115 vs. 94 min, respectively, p < 0.006), with the effect primarily seen during off-hours with a 28% reduction in median door-to-puncture times.

Conclusions: Institutional protocols help diminish the weekend effect in endovascular stroke treatment. This is driven largely by improvement in off-hours performance, with protocol adherence leading to further decreases in treatment intervals over time.

Neuro-Interventional Management of Acute Ischemic Stroke

Restoration of cerebral blood flow is the most important step in preventing irreversible damage to hypoperfused brain cells after ischemic stroke from large-vessel occlusion. For those patients who do not respond to (or are not eligible for) intravenous thrombolysis, endovascular therapy has become standard of care. A shift is currently taking place from rigid time windows for intervention (time is brain) to physiology-driven paradigms that rely heavily on neuroimaging. At this time, one can reasonably anticipate that more patients will be treated, and that outcomes will keep improving. This article discusses in detail recent advances in endovascular stroke therapy.

First-Line A Direct Aspiration First-Pass Technique vs. First-Line Stent Retriever for Acute Ischemic Stroke Therapy: A Meta-Analysis

Background: Recent trials have proved the efficacy of mechanical thrombectomy over medical treatment for patients with acute ischemic stroke, with the balance of equivalent rates of adverse events. Stent retrievers were applied predominantly in most trials; however, the role of other thrombectomy devices has not been well validated. A direct aspiration first-pass technique (ADAPT) is proposed to be a faster thrombectomy technique than the stent retriever technique. This meta-analysis investigated and compared the efficacy and adverse events of first-line ADAPT with those of first-line stent retrievers in patients with acute ischemic stroke.

Methods: A structured search was conducted comprehensively. A total of 1623 papers were found, and 4 articles were included in our meta-analysis. The Critical Appraisal Skills Programme tools were applied to evaluate the quality of studies. The primary outcome was defined as the proportion of patients with the Thrombolysis in Cerebral Ischemia (TICI) scale of 2b/3 at the end of all procedures. Secondary outcomes were the proportion of patients with functional independence (modified Rankin scale of 0–2) at the third month, the proportion of patients with the Thrombolysis in Cerebral Ischemia (TICI) scale of 2b/3 by primary chosen device, and the proportion of patients who received rescue therapies. Safety outcomes were the symptomatic intracranial hemorrhage (sICH) rate and the mortality rate within 3 months.

Results: One randomized controlled trial, one prospective cohort study, and two retrospective cohort studies were included. No significant difference between these 2 strategies of management were observed in the primary outcome (TICI scale at the end of all procedures, odds ratio [OR] = 0.78), two secondary outcomes (functional independence at the third month, OR = 1.16; TICI scale by primary chosen device, OR = 1.25), and all safety outcomes (sICH rate, OR = 1.56; mortality rate, OR = 0.91). The proportion of patients who received rescue therapies was higher in the first-line ADAPT group (OR = 0.64).

Conclusions: Among first-line thrombectomy devices for patients with ischemic stroke, ADAPT with the latest thrombosuction system was as efficient and safe as stent retrievers.

Unfavorable Vascular Anatomy Is Associated with Increased Revascularization Time and Worse Outcome in Anterior Circulation Thrombectomy

BACKGROUND

Reperfusion time influences patient outcome in mechanical thrombectomy for large vessel occlusion. We analyzed anatomic features that could be used to make preoperative and intraoperative decisions to minimize revascularization time.

METHODS

We reviewed a prospectively maintained database for patients with stroke evaluated from February 2015 to July 2016. Patients received a score based on bovine arch, aortic arch, and internal carotid artery dolichoarteriopathy (B.A.D. score), which we correlated with procedural times and outcomes. Univariate analysis was performed to identify predictors of procedural times, revascularization, complications, and outcome. Relevant variables were assessed via multivariate regression.

RESULTS

We identified 61 patients (31 men) who underwent transfemoral thrombectomy. Mean puncture to reperfusion time was 46 minutes. Age >75 years (odds ratio [OR] = 3.98; 95% confidence interval [CI], 1.17-13.54; P = 0.027) and high B.A.D. score (OR = 2.55; 95% CI, 1.17-5.57; P = 0.019) were significant predictors of puncture to reperfusion time >40 minutes. Mean puncture to first-pass time was 24 ± 14.2 minutes. Age >65 years (OR = 4.68; 95% CI, 1.07-20.55; P = 0.041) and high B.A.D. score (OR = 2.84; 95% CI, 1.18-6.85; P = 0.020) were independently predictive of time to first pass >20 minutes. Lower scores predicted higher Thrombolysis In Cerebral Infarction score (OR = 0.07; 95% CI, 0.01-0.81; P = 0.033). Higher scores predicted hemorrhagic transformation (OR = 4.8; 95% CI, 1.19-12.29; P = 0.024) and modified Rankin Scale score >4 (OR = 3.0; 95% CI, 1.15-7.92; P = 0.025) after thrombectomy.

CONCLUSIONS

Bovine variation, aortic arch type, and internal carotid artery dolichoarteriopathy are associated with increased revascularization time and poor outcomes in thrombectomy. We developed the B.A.D. score to predict reperfusion time and outcomes, demonstrating need for preoperative anatomic evaluation to guide treatment.

Consensus Statements by Korean Society of Interventional Neuroradiology and Korean Stroke Society: Hyperacute Endovascular Treatment Workflow to Reduce Door-to-Reperfusion Time

Recent clinical trials demonstrated the clinical benefit of endovascular treatment (EVT) in patients with acute ischemic stroke due to large vessel occlusion. These trials confirmed that good outcome after EVT depends on the time interval from symptom onset to reperfusion and that in-hospital delay leads to poor clinical outcome. However, there has been no universally accepted in-hospital workflow and performance benchmark for rapid reperfusion. Additionally, wide variety in workflow for EVT is present between each stroke centers. In this consensus statement, Korean Society of Interventional Neuroradiology and Korean Stroke Society Joint Task Force Team propose a standard workflow to reduce door-to-reperfusion time for stroke patients eligible for EVT. This includes early stroke identification and pre-hospital notification to stroke team of receiving hospital in pre-hospital phase, the transfer of stroke patients from door of the emergency department to computed tomography (CT) room, warming call to neurointervention (NI) team for EVT candidate prior to imaging, NI team preparation in parallel with thrombolysis, direct transportation from CT room to angiography suite following immediate decision of EVT and standardized procedure for rapid reperfusion. Implementation of optimized workflow will improve stroke time process metrics and clinical outcome of the patient treated with EVT.

ADAPT technique with ACE68 and ACE64 reperfusion catheters in ischemic stroke treatment: results from the PROMISE study

Background and purpose

The recent randomized trials demonstrated the benefit of mechanical thrombectomy in stroke therapy. However, treatment using different strategies is an ongoing area of investigation. The PROMISE study analyzed the safety and effectiveness of the Penumbra System with the ACE68 and ACE64 reperfusion catheters in aspiration thrombectomy of stroke, using A Direct Aspiration First Pass Technique (ADAPT).

Methods

PROMISE was a prospective study which enrolled 204 patients with intracranial anterior circulation large vessel occlusion (LVO) ischemic stroke in 20 centers from February 2016 to May 2017. Initial treatment was with the ACE68/ACE64 catheters within 6 hours of symptom onset. Imaging and safety review was performed by an independent Core Laboratory and a Clinical Events Committee. The primary angiographic outcome was revascularization to mTICI 2b-3 at immediate post-procedure and the primary clinical outcome was 90-day modified Rankin Scale (mRS) score ≤2. Safety assessment included device- and procedure-related serious adverse events (SAEs), symptomatic intracranial hemorrhage (sICH), mortality, and embolization of new territory (ENT).

Results

Enrolled patients had a median age of 74 (IQR 65–80) years and a median admission NIHSS of 16 (IQR 11–20). The post-procedure mTICI 2b-3 revascularization rate was 93.1% and the 90-day mRS 0–2 rate was 61%. Device- and procedure-related SAEs at 24 hours occurred in 1.5% and 3.4%, respectively, 90-day mortality was 7.5%, sICH occurred in 2.9% while ENT occurred in 1.5%.

Conclusions

For frontline therapy of LVO stroke, the ACE68/ACE64 catheters for aspiration thrombectomy were found to be safe and showed similar efficacy to randomized trials using other revascularization techniques.

Clinical Trial Registration

NCT02678169; Pre-results.

Consensus Statements by Korean Society of Interventional Neuroradiology and Korean Stroke Society: Hyperacute Endovascular Treatment Workflow to Reduce Door-to-Reperfusion Time

Recent clinical trials demonstrated the clinical benefit of endovascular treatment (EVT) in patients with acute ischemic stroke due to large vessel occlusion. These trials confirmed that good outcome after EVT depends on the time interval from symptom onset to reperfusion and that in-hospital delay leads to poor clinical outcome. However, there has been no universally accepted in-hospital workflow and performance benchmark for rapid reperfusion. Additionally, wide variety in workflow for EVT is present between each stroke centers. In this consensus statement, Korean Society of Interventional Neuroradiology and Korean Stroke Society Joint Task Force Team propose a standard workflow to reduce door-to-reperfusion time for stroke patients eligible for EVT. This includes early stroke identification and pre-hospital notification to stroke team of receiving hospital in pre-hospital phase, the transfer of stroke patients from door of the emergency department to computed tomography (CT) room, warming call to neurointervention team for EVT candidate prior to imaging, neurointervention team preparation in parallel with thrombolysis, direct transportation from CT room to angiography suite following immediate decision of EVT and standardized procedure for rapid reperfusion. Implementation of optimized workflow will improve stroke time process metrics and clinical outcome of the patient treated with EVT.

Optimized Management of Endovascular Treatment for Acute Ischemic Stroke

This manuscript describes a streamlined protocol for the management of patients with acute ischemic stroke, which aims at the minimization of time from hospital admission to reperfusion. Rapid restoration of cerebral blood flow is essential for the outcomes of patients with acute ischemic stroke. Endovascular treatment (EVT) has become the standard of care to accomplish this in patients with acute stroke due to large vessel occlusion (LVO). To achieve reperfusion of ischemic brain regions as fast as possible, all in-hospital time delays have to be carefully avoided. Therefore, management of patients with acute ischemic stroke was optimized with an interdisciplinary standard operating procedure (SOP). Stroke neurologists, diagnostic as well as interventional neuroradiologists, and anesthesiologists streamlined all necessary processes from patient admission and diagnosis to EVT of eligible patients. Target times for every step were established. Actually achieved times were prospectively recorded along with clinical data and imaging scores for all endovascularly treated stroke patients. These data were regularly analyzed and discussed in interdisciplinary team meetings. Potential issues were evaluated and all staff involved was trained to adhere to the SOP. This streamlined patient management approach and enhanced interdisciplinary collaboration reduced time from patient admission to reperfusion significantly and was accompanied by a beneficial effect on clinical outcomes.

Improving mechanical thrombectomy time metrics in the angiography suite: Stroke cart, parallel workflows, and conscious sedation

Purpose Earlier reperfusion of large-vessel occlusion (LVO) stroke improves functional outcomes. We hypothesize that use of a stroke cart in the angiography suite, containing all commonly used procedural equipment in a mechanical thrombectomy, combined with parallel staff workflows, and use of conscious sedation when possible, improve mechanical thrombectomy time metrics. Methods We identified 47 consecutive LVO patients who underwent mechanical thrombectomy at our center, retrospectively and prospectively from implementation of these three workflow changes (19 pre- and 28 post-). For each patient, last known normal, NIHSS, angiography suite in-room time, type of anesthesia, groin puncture time, on-clot time, recanalization time, LVO location, number of passes, device(s) used, mTICI score, and outcome (mRS) were recorded. Between-group comparisons of time metrics and multivariate regression were performed. Results Stroke cart, parallel workflows, and primary use of conscious sedation decreased in-room time to groin puncture (-21.3 min, p < 0.0001), in-room to on-clot time (-24.1 min, p = 0.001), and in-room to reperfusion time (-29.5 min, p = 0.01). In a multivariate analysis, endotracheal intubation and general anesthesia were found to significantly increase in-room to on-clot time ( p = 0.01), in-room to reperfusion time ( p = 0.01), and groin puncture to on-clot time ( p = 0.05). The number of patients achieving a good outcome (mRS 0-2), however, did not significantly differ between the two groups (9/18 (47%) vs 14/28 (50%), p = 0.60). Conclusions Use of a stroke cart, parallel workflows by neurointerventionalists, technologists, and nursing staff, and use of conscious sedation may be useful to other institutions in efforts to improve procedural times.

Latest generation of flat detector CT as a peri-interventional diagnostic tool: a comparative study with multidetector CT

Background and purpose

Flat detector CT (FDCT) has been used as a peri-interventional diagnostic tool in numerous studies with mixed results regarding image quality and detection of intracranial lesions. We compared the diagnostic aspects of the latest generation FDCT with standard multidetector CT (MDCT).

Materials and methods

102 patients were included in our retrospective study. All patients had undergone interventional procedures. FDCT was acquired peri-interventionally and compared with postinterventional MDCT regarding depiction of ventricular/subarachnoidal spaces, detection of intracranial hemorrhage, and delineation of ischemic lesions using an ordinal scale. Ischemic lesions were quantified with the Alberta Stroke Program Early CT Scale (ASPECTS) on both examinations. Two neuroradiologists with varying grades of experience and a medical student scored the anonymized images separately, blinded to the clinical history.

Results

The two methods were of equal diagnostic value regarding evaluation of the ventricular system and the subarachnoidal spaces. Subarachnoidal, intraventricular, and parenchymal hemorrhages were detected with a sensitivity of 95%, 97%, and 100% and specificity of 97%, 100%, and 99%, respectively, using FDCT. Gray–white differentiation was feasible in the majority of FDCT scans, and ischemic lesions were detected with a sensitivity of 71% on FDCT, compared with MDCT scans. The mean difference in ASPECTS values on FDCT and MDCT was 0.5 points (95% CI 0.12 to 0.88).

Conclusions

The latest generation of FDCT is a reliable and accurate tool for the detection of intracranial hemorrhage. Gray–white differentiation is feasible in the supratentorial region.