Stroke and transient ischaemic attack in over 16s: diagnosis and initial management

This guideline covers interventions in the acute stage of a stroke or transient ischaemic attack (TIA). It offers the best clinical advice on the diagnosis and acute management of stroke and TIA in the 48 hours after onset of symptoms. In April 2022, we reviewed the evidence and made new recommendations on blood pressure control for people with acute intracerebral haemorrhage.

Anaesthesia for mechanical thrombectomy: a narrative review.

Stroke is a leading cause of death and disability, and is associated with a huge societal and economic burden. Interventions for the immediate treatment of ischaemic stroke due to large vessel occlusion are dependent on recanalisation of the occluded vessel. Trials have provided evidence supporting the efficacy of mechanical thrombectomy in ischaemic stroke due to large vessel occlusion. This has resulted in changes in management and organisation of stroke care worldwide. Major determinants of effectiveness of thrombectomy include: time between stroke onset and reperfusion; location of occlusion and local collateral perfusion; adequacy of reperfusion; patient age; and stroke severity. The role of anaesthetic technique on outcome remains controversial with published research showing conflicting results. As a result, choice of conscious sedation or general anaesthesia for mechanical thrombectomy is often dependent on individual operator choice or institutional preference. More recent randomised controlled trials have suggested that protocol-driven general anaesthesia is no worse than conscious sedation and may even be associated with better outcomes. These and other studies have highlighted the importance of optimal blood pressure management as a major determinant of patient outcome. Anaesthetic management should be tailored to the individual patient and circumstances. Acute ischaemic stroke is a neurological emergency; clinicians should focus on minimising door-to-groin puncture time and the provision of high-quality periprocedural care with a particular emphasis on the maintenance of an adequate blood pressure.

MS CGPClin2: experiência em PIE

Priscilla Souza, CGPClin, sobre uso de Evidências em Saúde sobre o uso de Trombectomia em casos de AVC.

Scoping Review of Clinical Practice Guidelines for the Early Management of Stroke with Focus on Endovascular Treatment.

BACKGROUND: Stroke represents one of the major causes of death and long-term disability worldwide and, even when new treatment strategies have been identified, there is a need of quality clinical practice guidelines (CPGs) to guide and improve acute stroke care. We aim to describe the characteristics and assess the quality of CPGs in endovascular treatment for acute ischemic stroke due to anterior-circulation large-vessel occlusion. METHODS: We conducted a scoping review of CPGs that assessed stroke management. We searched the following databases: PubMed, TripDatabase, Scopus, and Google Scholar to identify CPGs published or updated in the last 3 years and used Appraisal of Guidelines Research and Evaluation II to assess the quality of the guidelines. RESULTS: We found a total of 9 CPGs published or updated between 2018 and 2020, from which only one third had adequate methodologic rigor. Guidelines presented pitfalls related to evidence search, assessment, and methods used to reach the recommendations. All the CPGs considered a 24-hour extended window of treatment and the CPGs considered the use of similar imaging techniques to diagnose and explore the extent of the stroke. However, there were variations regarding the selection criteria for thrombectomy. CONCLUSIONS: The quality of the CPGs varied widely, which issues around the identification and assessment of the evidence used to reach recommendations. Despite this, the recommendations regarding the use of thrombectomy were similar across the CPGs. Readers need to carefully assess the methodologic rigor of CPGs before applying them to their clinical practice.

Predicting 90-Day Outcome After Thrombectomy: Baseline-Adjusted 24-Hour NIHSS Is More Powerful Than NIHSS Score Change.

BACKGROUND AND PURPOSE: The National Institutes of Health Stroke Scale (NIHSS) measured at an early time point is an appealing surrogate marker for long-term functional outcome of stroke patients treated with endovascular therapy. However, definitions and analytical methods for an early NIHSS-based outcome measure that optimize power and precision in clinical studies are not well-established. METHODS: In this post-hoc analysis of our prospective observational study that enrolled endovascular therapy-treated patients at 12 comprehensive stroke centers across the US, we compared the ability of 24-hour NIHSS, ΔNIHSS (baseline minus 24-hour NIHSS), and percentage change (NIHSS×100/baseline NIHSS), analyzed as continuous and dichotomous measures, to predict 90-day modified Rankin Scale (mRS) using logistic regression (adjusted for age, baseline NIHSS, glucose, hypertension, Alberta Stroke Program Early CT Score, time to recanalization, recanalization status, and intravenous thrombolysis) and Spearman ρ. RESULTS: Of 485 patients in the BEST (Blood Pressure After Endovascular Stroke Therapy) cohort, 446 (92%) with 90-day follow-up data were included. An absolute 24-hour NIHSS, adjusted for baseline in multivariable modeling, had the highest predictive power of all definitions evaluated (aR2 0.368 and adjusted odds ratio 0.79 [0.75-0.84], P<0.001 for mRS score 0-2; aR2 0.444 and adjusted odds ratio 0.84 [0.8-0.86] for ordinal mRS). For predicting mRS score of 0-2 with a cut point, the second most efficient approach, the optimal threshold for 24-hour NIHSS score was ≤7 (sensitivity 80.1%, specificity 80.4%; adjusted odds ratio 12.5 [7.14-20], P<0.001), followed by percent change in NIHSS (sensitivity 79%, specificity 58.5%; adjusted odds ratio 4.55 [2.85-7.69], P<0.001). CONCLUSIONS: Twenty-four-hour NIHSS, adjusted for baseline, was the strongest predictor of both dichotomous and ordinal 90-day mRS outcomes for endovascular therapy-treated patients. A dichotomous 24-hour NIHSS score of ≤7 was the second-best predictor. Although ΔNIHSS, continuous and dichotomized at ≥4, predicted 90-day outcomes, absolute 24-hour NIHSS definitions performed better.

The multidisciplinary management of hepatocellular carcinoma with portal vein tumor thrombus.

Portal vein tumor thrombus (PVTT) is one of the most common complications of hepatocellular carcinoma (HCC), which refers to the advanced stage of HCC and indicates an extremely poor prognosis. Monotherapy cannot effectively prolong the survival benefit of patients with HCC-PVTT characterized by a high recurrence rate. With great progress in the area of immune and molecular targeted therapy, there comes a promising era of multidisciplinary management of HCC. Survival benefits can be achieved based on accurate diagnosis, staging, and multidisciplinary management. Additionally, in terms of the presence of controversy about the standard treatment algorithm and the absence of universal treatment guidelines, a multidisciplinary management program may afford the best hope for HCC-PVTT patients via appropriate implement of various treatment protocols.

Stroke Microsurgical Thrombectomy Human Placenta Simulator.

BACKGROUND: Stroke microsurgical cerebrovascular thrombectomy reports are limited, although this technique could be used in many centers as a primary treatment or a salvage intervention option. It requires great ability, so our aim is to describe and validate a stroke microsurgical thrombectomy ex vivo simulator with operative nuances analysis. METHODS: Human placenta (HP) models simulated middle cerebral artery vessels with intraluminal thrombus to be microsurgically excised. Six neurosurgeons performed 1-mm and 2-mm longitudinal and transverse arteriotomy in different arteries to remove a 1.5-cm length thrombus. Validation through construct validity compared time to complete the task, complete vessel cleaning, vessel manipulation, vessel stenosis, and leakage in both techniques. RESULTS: All 6 HP models reproduced with fidelity stroke microsurgical thrombectomy, so participants completed 24 sessions, 4 for each neurosurgeon on the same model in different arteries. Construct validity highlighted microsurgical technical difficulties with positive results obtained by parameters variation during performance. Transverse arteriotomy with 1-mm length had best results (P < 0.05) allowing complete thrombus removal, less stenosis, and minor leakage in abbreviated time. CONCLUSIONS: A HP simulator can reproduce with high fidelity all stroke microsurgical thrombectomy part tasks. Transverse 1-mm arteriotomy followed by thrombectomy and 2 simple sutures can fulfill all quality assurance aspects in such intervention accordingly to training model, due to easier vessel opening, complete thrombus removal, no stenosis, and faster microsuture.

Evaluation of stroke thrombectomy including patients where IV thrombolysis is contraindicated or has failed: a randomized trial of two novel thrombectomy devices.

BACKGROUND: Study was a PROBE design phase II randomized controlled trial (RCT). We assessed trial feasibility and technical efficacy and safety of two novel thrombectomy devices - ERIC (a retriever device) and SOFIA (a distal access catheter) - used alone or in combination depending on operator preference. METHODS: Four UK neuroscience centers enrolled adults with proximal large artery occlusion (LAO) stroke on imaging where arterial puncture was achievable within 5.5 hours (8.5 hours for posterior circulation) of symptom onset; National Institutes of Health Stroke Scale (NIHSS) ≥6 with limited ischemic change on CT imaging. Randomization was 2:1 into intervention arm (ERIC and/or SOFIA). Patients and core lab were blinded to allocation. Primary outcome was independent core lab adjudication of reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) scale). Secondary outcomes were modified Rankin score (mRS) at 90 and 365 days (independence and shift analysis), 30-day mortality, symptomatic intracranial hemorrhage (sICH), procedural complications and NIHSS change. RESULTS: Sixty-six patients were enrolled. TICI 2B/3 reperfusion was achieved in 72% in intervention compared with 90% in control arm on intention to treat (ITT) analysis (P=0.2) and 78% compared with 86% on per protocol analysis (P=0.7). Functional independence at 90 days was 40% (intervention) compared with 43% (control) on ITT analysis (P=1.0). sICH rates were low at 0% and 5%, respectively (P=0.3). The 30-day mortality was 9% intervention compared with 14% control (P=0.7). CONCLUSIONS: Study indicated feasibility of a phase II RCT trial approach for assessing new thrombectomy devices. In a broad LAO stroke population ERIC and SOFIA were not statistically different from control devices. Larger trials are needed.

Choosing an Effective and Safe Direct Aspiration Setup for Tortuous Anatomy in Acute Ischemic Stroke: In vitro Study in a Physiological Flow Model.

PURPOSE: A direct aspiration first pass technique (ADAPT) is an effective thrombectomy option in patients with acute ischemic stroke. Balloon guide catheters (BGC) seem to improve the efficacy of stent retrievers and ADAPT. The last generation 6F aspiration catheters require 9F BGCs, which are rigid devices that are challenging to position in a tortuous anatomy. In this experimental study the efficacy of 6F ADAPT alone and 5F ADAPT combined with 8F BGC was evaluated. MATERIALS AND METHODS: Either a fibrin rich (white) clot or an RBC rich (red) clot was placed in the M1 segment of a transparent silicon phantom. Physiological hemodynamic conditions were maintained. The clots were retrieved by 6F aspiration catheter via 8F long sheath or 5F aspiration catheter via a flexible 8F BGC. Thrombectomy was performed under direct visual control. The primary endpoints were the number of passes and the number of distal emboli. RESULTS: Ten experiments were made with each clot model and thrombectomy technique (n = 40). Full recanalization could be achieved in every experiment. First pass mTICI 3 could be achieved by 6F ADAPT in 80 % of red clots and 90 % of white clots. Distal emboli were caused in 10 % and 20 %, respectively. When using 5F ADAPT combined with BGC, a first pass mTICI 3 rate of 90 % in red clots and 100 % in white clots could be achieved. A 10 % rate of distal emboli occurred in both groups. In almost all experiments (both techniques), the thrombi clogged the aspiration catheter. No statistically significant differences could be found between the techniques and clot models. CONCLUSION: 6F ADAPT without BGC was as effective as 5F ADAPT combined with a flexible 8F BGC, with both techniques showing high first-pass recanalization rates and low distal emboli rates. Especially in the case of a tortuous anatomy, these setups should be considered as alternatives to a rigid 9F BGC. The thrombus compositions seemed to be irrelevant in this setting. KEY POINTS: · 6F ADAPT with no BGC and 5F ADAPT with BGC were very effective and performed equally.. · Both techniques should be considered in tortuous anatomy.. · In this setting the clot composition showed no effect on the recanalization rate.. CITATION FORMAT: · Madjidyar J, Nerkada L, Larsen N et al. Choosing an Effective and Safe Direct Aspiration Setup for Tortuous Anatomy in Acute Ischemic Stroke: In vitro Study in a Physiological Flow Model. Fortschr Röntgenstr 2021; 193: 544 - 550.

Management of cardiovascular emergencies during the COVID-19 pandemic.

BACKGROUND: It has been reported that patients attending the emergency department with other pathologies may not have received optimal medical care due to the lockdown measures in the early phase of the COVID-19 pandemic. METHODS: This was a retrospective study of patients presenting with cardiovascular emergencies to four tertiary regional emergency departments in western India during the government implementation of complete lockdown. RESULTS: 25.0% of patients during the lockdown period and 17.4% of patients during the pre-lockdown period presented outside the window period (presentation after 12 hours of symptom onset) compared with only 6% during the pre-COVID period. In the pre-COVID period, 46.9% of patients with ST elevation myocardial infarction underwent emergent catheterisation, while in the pre-lockdown and lockdown periods, these values were 26.1% and 18.8%, respectively. The proportion of patients treated with intravenous thrombolytic therapy increased from 18.4% in the pre-COVID period to 32.3% in the post-lockdown period. Inhospital mortality for acute coronary syndrome (ACS) increased from 2.69% in the pre-COVID period to 7.27% in the post-lockdown period. There was also a significant decline in emergency admissions for non-ACS conditions, such as acute decompensated heart failure and high degree or complete atrioventricular block. CONCLUSION: The COVID-19 pandemic has led to delays in patients seeking care for cardiac problems and also affected the use of optimum therapy in our institutions.

Current Recommendations for the Management of Stroke Patients in the Middle East in the Era of COVID-19 Pandemic; Statement from the MENA SINO.

COVID-19 pandemic has led to a change in the way we manage acute medical illnesses. This pandemic had a negative impact on stroke care worldwide. The World Stroke Organization (WSO) has raised concerns due to the lack of available care and compromised acute stroke services globally. The numbers of thrombolysis and thrombectomy therapies are declining. As well as, the rates and door-to treatment times for thrombolysis and thrombectomy therapies are increasing. The stroke units are being reallocated to serve COVID-19 patients, and stroke teams are being redeployed to COVID-19 centers. Covid 19 confirmed cases and deaths are rising day by day. This pandemic clearly threatened and threatening all stroke care achievements regionally. Managing stroke patients during this pandemic is even more challenging at our region. The Middle East and North Africa Stroke and Interventional Neurotherapies Organization (MENA-SINO) is the main stroke organization regionally. MENA-SINO urges the need to developing new strategies and recommendations for stroke care during this pandemic. This will require multiple channels of interventions and create a protective code stroke with fast triaging path. Developing and expanding the tele-stroke programs are urgently required. There is an urgent need for enhancing collaboration and cooperation between stroke expertise regionally and internationally. Integrating such measures will inevitably lead to an improvement and upgrading of the services to a satisfactory level.

Reperfusion therapies in pulmonary embolism-state of the art and expert opinion: A position paper from the "Unité de Soins Intensifs de Cardiologie" group of the French Society of Cardiology.

Acute pulmonary embolism is a frequent cardiovascular emergency with an increasing incidence. The prognosis of patients with high-risk and intermediate-high-risk pulmonary embolism has not improved over the last decade. The current treatment strategies are mainly based on anticoagulation to prevent recurrence and reduce pulmonary vasculature obstruction. However, the slow rate of thrombus lysis under anticoagulation is unable to acutely decrease right ventricle overload and pulmonary vasculature resistance in patients with severe obstruction and right ventricle dysfunction. Therefore, patients with high-risk and intermediate-high-risk pulmonary embolism remain a therapeutic challenge. Reperfusion therapies may be discussed for these patients, and include systemic thrombolysis, catheter-directed therapies and surgical thrombectomy. High-risk patients require systemic thrombolysis, but may have contraindications as a result of the high risk of bleeding. In addition, intermediate-high-risk patients should not receive systemic thrombolysis, despite its high efficacy, because of prohibitive bleeding complications. Recently, percutaneous reperfusion techniques have been developed to acutely decrease pulmonary vascular obstruction with lower-dose or no thrombolytic agents and, thus, potentially higher safety than systemic thrombolysis. Some of these techniques improve key haemodynamic variables. Cardiac surgical techniques and venoarterial extracorporeal membrane oxygenation as temporary circulatory support may be useful in selected cases. The development of pulmonary embolism centres with multidisciplinary pulmonary embolism teams is mandatory to enable adequate use of reperfusion and improve outcomes. We aim to present the state of the art regarding reperfusion therapies in pulmonary embolism, but also to provide guidance on their indications and patient selection.

Endovascular Treatment of Acute Ischemic Stroke.

PURPOSE OF REVIEW: This article reviews the actual indications for mechanical thrombectomy in patients with acute ischemic stroke and how the opportunities for endovascular therapy can be expanded by using the concept of clinical-imaging or perfusion-imaging mismatch (as a surrogate for salvageable tissue) rather than time of ischemia. RECENT FINDINGS: Six randomized controlled trials undoubtedly confirmed the benefits of using endovascular thrombectomy on the clinical outcome of patients with stroke with large vessel occlusion within 6 hours from symptom onset compared with those receiving only standard medical care. In a meta-analysis of individual patient data, the number needed to treat with endovascular thrombectomy to reduce disability by at least one level on the modified Rankin Scale for one patient was 2.6. Recently, the concept of "tissue window" versus time window has proved useful for selecting patients for mechanical thrombectomy up to 24 hours from symptom onset. The DAWN (DWI or CTP Assessment With Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention) trial included patients at a median of 12.5 hours from onset and showed the largest effect in functional outcome ever described in any acute stroke treatment trial (35.5% increase in functional independence). In DEFUSE 3 (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution 3), patients treated with mechanical thrombectomy at a median of 11 hours after onset had a 28% increase in functional independence and an additional 20% absolute reduction in death or severe disability. SUMMARY: For patients with acute ischemic stroke and a large vessel occlusion in the proximal anterior circulation who can be treated within 6 hours of stroke symptom onset, mechanical thrombectomy with a second-generation stent retriever or a catheter aspiration device should be indicated regardless of whether the patient received treatment with intravenous (IV) recombinant tissue plasminogen activator (rtPA) in patients with limited signs of early ischemic changes on neuroimaging. Two clinical trials completely disrupted the time window concept in acute ischemic stroke, showing excellent clinical outcomes in patients treated up to 24 hours from symptom onset. Time of ischemia is, on average, a good biomarker for tissue viability; however, the window of opportunity for treatment varies across different individuals because of a range of compensatory mechanisms. Adjusting time to the adequacy of collateral flow leads to the concept of tissue window, a paradigm shift in stroke reperfusion therapy.

Workflow patterns and potential for optimization in endovascular stroke treatment across the world: results from a multinational survey.

BACKGROUND: The benefit of endovascular treatment (EVT) is highly time-dependent, and treatment delays reduce patients' chances to achieve a good outcome. In this survey-based study, we aimed to evaluate current in-hospital EVT workflow characteristics across different countries and hospital settings, and to quantify the time-savings that could be achieved by optimizing particular workflow steps. METHODS: In a multinational survey, neurointerventionalists were asked to provide specific information about EVT workflows in their current working environment. Workflow characteristics were summarized using descriptive statistics and stratified by country and physician characteristics, such as age, career stage, personal and institutional caseload. RESULTS: Among 248 respondents from 48 countries, pre-notification of the neurointerventional team was used in 70% of cases. The emergency department (ED) and CT scanner, and the CT scanner and neuroangiography suite, were on different floors in 23% and 38%, respectively. Redundant procedures in the ED were often routinely performed, such as chest x-rays (in 6%). General anesthesia was the most frequently used anesthesia protocol for EVT (42%), and an anesthesiologist was available in 82% for this purpose. 52% of the participants used a pre-prepared EVT kit. CONCLUSION: The current structure of EVT workflows offers possibilities for improvement. While some bottlenecks, such as the spatial department set-up, cannot easily be resolved, pre-notification tools and pre-prepared EVT kits are more straightforward to implement and could help to reduce treatment delays, and thereby improve patient outcomes.

Decreasing Door-to-Groin Puncture Times in a Nonacademic Comprehensive Stroke Center.

BACKGROUND AND PURPOSE: Our organization was experiencing a delay in treatment of large vessel occlusions. With a goal of door-to-groin puncture in less than 90 minutes, our organization was averaging a door-to-groin puncture time of greater than 100 minutes and identified the need for a process change. METHODS: A multidisciplinary group was formed to process map current state and define future state. Lean methodology was used to implement rapid cycle change and create standard work. Because this was an improvement on a current process, institutional review board approval was not needed. RESULTS: The result was achieving door-to-groin puncture times less than 90 minutes and a subsequent decrease in door-to-groin puncture goal to less than 80 minutes. In addition, improved communication was seen between multiple departments responsible for the care of large vessel occlusion patients. CONCLUSION: Using Lean methodology with a multidisciplinary team is effective for implementing and sustaining process change.

Safety and Effectiveness of Neuro-thrombectomy on Single compared to Biplane Angiography Systems.

An increasing number of centers not necessarily equipped with biplane (BP) angiosuites are performing mechanical thrombectomy (MT) in acute ischemic stroke patients. We assessed whether MT performed on single-plane (SP) is equivalent in terms of safety, effectiveness, radiation and contrast agent exposure. Consecutive patients treated by MT in four high volume centers between January 2014 and May 2017 were included. Demographic and MT characteristics were assessed and compared between SP and BP. Of 906 patients treated by MT, 576 (64%) were handled on a BP system. After multivariate analysis, contrast load and fluoroscopy duration were significantly lower in the BP group [100vs200mL, relative effect 0.85 (CI: 0.79-0.92), p = 0.0002; 22 vs 27 min, relative effect 0.84 (CI: 0.76-0.93), p = 0.0008, respectively]. There was no difference in recanalization (modified Thrombolysis-In-Cerebral-Infarction 2b-3), good clinical outcome (modified Rankin Scale 0-2), complications rates, procedure duration or radiation exposure. A three-vessel diagnostic angiogram performed prior to MT led to a significant increase in procedure duration (15% increase, p = 0.05), radiation exposure (33% increase, p < 0.0001) and contrast load (125% increase, p < 0.0001). Mechanical neuro-thrombectomy seems equally safe and effective on a single or biplane angiography system despite increased contrast load and fluoroscopy duration on the former.

Endovascular Thrombectomy for Acute Ischemic Strokes: Current US Access Paradigms and Optimization Methodology.

Background and Purpose- Timely access to endovascular thrombectomy (EVT) centers is vital for best acute ischemic stroke outcomes. Methods- US stroke-treating centers were mapped utilizing geo-mapping and stratified into non-EVT or EVT if they reported ≥1 acute ischemic stroke thrombectomy code in 2017 to Center for Medicare and Medicaid Services. Direct EVT-access, defined as the population with the closest facility being an EVT-center, was calculated from validated trauma-models adapted for stroke. Current 15- and 30-minute access were described nationwide and at state-level with emphasis on 4 states (TX, NY, CA, IL). Two optimization models were utilized. Model-A used a greedy algorithm to capture the largest population with direct access when flipping 10% and 20% non-EVT to EVT-centers to maximize access. Model-B used bypassing methodology to directly transport patients to the nearest EVT centers if the drive-time difference from the geo-centroid to hospital was within 15 minutes from the geo-centroid to the closest non-EVT center. Results- Of 1941 stroke-centers, 713 (37%) were EVT. Approximately 61 million (19.8%) Americans have direct EVT access within 15 minutes while 95 million (30.9%) within 30 minutes. There were 65 (43%) EVT centers in TX with 22% of the population currently within 15-minute access. Flipping 10% hospitals with top population density improved access to 30.8%, while bypassing resulted in 45.5% having direct access to EVT centers. Similar results were found in NY (current, 20.9%; flipping, 34.7%; bypassing, 50.4%), CA (current, 25.5%; flipping, 37.3%; bypassing, 53.9%), and IL (current, 15.3%; flipping, 21.9%; bypassing, 34.6%). Nationwide, the current direct access within 15 minutes of 19.8% increased by 7.5% by flipping the top 10% non-EVT to EVT-capable in all states. Bypassing non-EVT centers by 15 minutes resulted in a 16.7% gain in coverage. Conclusions- EVT-access within 15 minutes is limited to less than one-fifth of the US population. Optimization methodologies that increase EVT centers or bypass non-EVT to the closest EVT center both showed enhanced access. Results varied by states based on the population size and density. However, bypass showed more potential for maximizing direct EVT-access. National and state efforts should focus on identifying gaps and tailoring solutions to improve EVT-access.

Preclinical evaluation of the ANCD thrombectomy device: safety and efficacy in a swine clot model.

BACKGROUND: The Advanced Thrombectomy System (ANCD) provides a new funnel component designed to reduce clot fragmentation and facilitate retrieval in patients with stroke by locally restricting flow, allowing distal aspiration in combination with a stent retriever (SR). OBJECTIVE: To evaluate the preclinical efficacy and safety of the ANCD in a swine clot model. METHODS: Soft and firm clots were implanted in the lingual and cervical arteries of 11 swine to obtain Thrombolysis in Cerebral Infarction (TICI) 0 blood flow. Mechanical thrombectomy was performed with either a balloon guide catheter+Solitaire 2 stent retriever (BGC+SR, n=13) or ANCD+SR (n=13). TICI flow was evaluated and successful revascularization was defined as TICI 3 (normal perfusion). To characterize safety, a total of 3 passes were performed in each vessel independent of recanalization. Tissues were explanted for histopathological analysis after 3 and 30 days, respectively. RESULTS: First pass reperfusion rates were ANCD+SR: 69% and BGC+SR: 46%. Reperfusion increased after the third pass in both groups (ANCD+SR: 100%, vs BGC+SR: 77%). Recanalization was achieved after an average of 1.4 and 1.9 passes in ANCD+SR and BGC+SR (p=0.095), respectively. Vessel injury was comparable in both groups; endothelial loss at 3 days was the most common injury seen (ANCD+SR: 1.78±1.22; BGC+SR: 2.03±1.20; p=0.73), while other histopathological markers were absent or minimal. Tissues downstream from targeted vessels also showed absence or minimal lesions across both groups. CONCLUSIONS: Results in a swine clot model support the high efficacy of the ANCD+SR without causing clinically significant vessel injury potentially related to the new funnel component.

Development of an in vitro model of calcified cerebral emboli in acute ischemic stroke for mechanical thrombectomy evaluation.

: ​ BACKGROUND: Calcified cerebral emboli (CCEs) are a rare cause of acute ischemic stroke (AIS) and are frequently associated with poor outcomes. The presence of dense calcified material enables reliable identification of CCEs using non-contrast CT. However, recanalization rates with the available mechanical thrombectomy (MT) devices remain low. OBJECTIVE: To recreate a large vessel occlusion involving a CCE using an in vitro silicone model of the intracranial vessels and to demonstrate the feasability of this model to test different endovascular strategies to recanalize an occlusion of the M1 segment of the middle cerebral artery (MCA). : ​ METHODS: An in vitro model was developed to evaluate different endovascular treatment approaches using contemporary devices in the M1 segment of the MCA. The in vitro model consisted of a CCE analog placed in a silicone neurovascular model. Development of an appropriate CCE analog was based on characterization of human calcified tissues that represent likely sources of CCEs. Feasibility of the model was demonstrated in a small number of MT devices using four common procedural techniques. : ​ RESULTS: CCE analogs were developed with similar mechanical behavior to that of ex vivo calcified material. The in vitro model was evaluated with various MT techniques and devices to show feasibility of the model. In this limited evaluation, the most successful retrieval approach was performed with a stent retriever combined with local aspiration through a distal access catheter, and importantly, with flow arrest and dual aspiration using a balloon guide catheter. : ​ CONCLUSION: Characterization of calcified tissues, which are likely sources of CCEs, has shown that CCEs are considerably stiffer than thrombus. This highlights the need for a different in vitro AIS model for CCEs than those used for thromboemboli. Consequentially, an in vitro AIS model representative of a CCE occlusion in the M1 segment of the MCA has been developed.

Using G-FAST to recognize emergent large vessel occlusion: a training program for a prehospital bypass strategy.

INTRODUCTION: The shorter the time between the onset of symptoms and reperfusion using endovascular thrombectomy, the better the functional outcome of patients. A training program was designed for emergency medical technicians (EMTs) to learn the gaze-face-arm-speech-time test (G-FAST) score for initiating a prehospital bypass strategy in an urban city. This study aimed to evaluate the effect of the training program on EMTs. METHODS: All EMTs in the city were invited to join the training program. The program consisted of a 30 min lecture and a 20 min video which demonstrated the G-FAST evaluation. The participants underwent tests before and after the program. The tests included (1) a questionnaire of knowledge, attitudes, confidence, and behaviors towards stroke care; and (2) watching 10 different scenarios in a video and answering questions, including eight sub-questions of G-FAST parameters, and choosing a suitable receiving hospital. RESULTS: In total, 1058 EMTs completed the training program. After the program, significant improvement was noted in knowledge, attitudes, and confidence, as well as scenario judgement. The performance of the EMTs in evaluating G-FAST criteria in comatose patients was relatively poor in the pre-test and improved significantly after the training course. Although the participants answered the G-FAST items correctly, they tended to overtriage the patients and refer them to higher-level hospitals. CONCLUSIONS: A short training program can improve the ability to identify stroke patients and choose a suitable receiving hospital. A future training program could put further emphasis on how to evaluate comatose patients and choose a suitable receiving hospital.