STAIR XII (12th Stroke Treatment Academy Industry Roundtable) included a workshop to discuss the priorities for advancements in neuroimaging in the diagnostic workup of acute ischemic stroke. The ...workshop brought together representatives from academia, industry, and government. The participants identified 10 critical areas of priority for the advancement of acute stroke imaging. These include enhancing imaging capabilities at primary and comprehensive stroke centers, refining the analysis and characterization of clots, establishing imaging criteria that can predict the response to reperfusion, optimizing the Thrombolysis in Cerebral Infarction scale, predicting first-pass reperfusion outcomes, improving imaging techniques post-reperfusion therapy, detecting early ischemia on noncontrast computed tomography, enhancing cone beam computed tomography, advancing mobile stroke units, and leveraging high-resolution vessel wall imaging to gain deeper insights into pathology. Imaging in acute ischemic stroke treatment has advanced significantly, but important challenges remain that need to be addressed. A combined effort from academic investigators, industry, and regulators is needed to improve imaging technologies and, ultimately, patient outcomes.
Stent retriever thrombectomy is a pre-eminent treatment modality for large vessel ischaemic stroke. Simulation of thrombectomy could help understand stent and clot mechanics in failed cases and ...provide a digital testbed for the development of new, safer devices. Here, we present a novel,
thrombectomy method using a hybrid finite-element analysis (FEA) and smoothed particle hydrodynamics (SPH). Inspired by its biological structure and components, the blood clot was modelled with the hybrid FEA-SPH method. The Solitaire self-expanding stent was parametrically reconstructed from micro-CT imaging and was modelled as three-dimensional finite beam elements. Our simulation encompassed all steps of mechanical thrombectomy, including stent packaging, delivery and self-expansion into the clot, and clot extraction. To test the feasibility of our method, we simulated clot extraction in simple straight vessels. This was compared against
thrombectomies using the same stent, vessel geometry, and clot size and composition. Comparisons with benchtop tests indicated that our model was able to accurately simulate clot deflection and penetration of stent wires into the clot, the relative movement of the clot and stent during extraction, and clot fragmentation/embolus formation. In this study, we demonstrated that coupling FEA and SPH techniques could realistically model stent retriever thrombectomy.
Randomized controlled trials (RCTs) demonstrated a treatment effect of endovascular thrombectomy in acute ischemic stroke with large infarct, commonly defined as an Alberta Stroke Program Early CT ...Score (ASPECTS) of 3-5. However, data on endovascular thrombectomy in patients with very low ASPECTS of 0-2 remain scarce.
We conducted a systematic review and meta-analysis of RCTs comparing endovascular thrombectomy versus medical treatment alone in acute ischemic anterior circulation stroke with very large infarct, defined as ASPECTS of 0-2. The primary outcome was the shift toward better functional outcomes on the 90-day modified Rankin Scale (mRS). Random effects meta-analysis was performed using the generic inverse variance method.
Literature research identified four RCTs which evaluated the treatment effect of endovascular thrombectomy for large infarcts and provided a subgroup analysis of the mRS shift in patients with ASPECTS of 0-2. The pooled analysis showed a significant shift toward better 90-day mRS scores in favor of endovascular thrombectomy (pooled odds ratio, 1.62, 95% confidence interval, 1.29-2.04, P < 0.001).
This meta-analysis suggests a treatment effect of endovascular thrombectomy in specific patients with very low ASPECTS of 0-2, challenging the use of ASPECTS for treatment selection in acute ischemic stroke due to large vessel occlusion. An individual patient meta-analysis of RCTs would strengthen evidence in the treatment of patients with ASPECTS of 0-2.
Optimal anesthetic strategy for the endovascular treatment of stroke is still under debate. Despite scarce data concerning anesthetic management for medium and distal vessel occlusions (MeVOs) some ...centers empirically support a general anesthesia (GA) strategy in these patients.
We conducted an international retrospective study of MeVO cases. A propensity score matching algorithm was used to mitigate potential differences across patients undergoing GA and conscious sedation (CS). Comparisons in clinical and safety outcomes were performed between the two study groups GA and CS. The favourable outcome was defined as a modified Rankin Scale (mRS) 0-2 at 90 days. Safety outcomes were 90-days mortality and symptomatic intracranial hemorrhage (sICH). Predictors of a favourable outcome and sICH were evaluated with backward logistic regression.
After propensity score matching 668 patients were included in the CS and 264 patients in the GA group. In the matched cohort, either strategy CS or GA resulted in similar rates of good functional outcomes (50.1% vs. 48.4%), and successful recanalization (89.4% vs. 90.2%). The GA group had higher rates of 90-day mortality (22.6% vs. 16.5%, p < 0.041) and sICH (4.2% vs. 0.9%, p = 0.001) compared to the CS group. Backward logistic regression did not identify GA vs CS as a predictor of good functional outcome (OR for GA vs CS = 0.95 (0.67-1.35)), but GA remained a significant predictor of sICH (OR = 5.32, 95% CI 1.92-14.72).
Anaesthetic strategy in MeVOs does not influence favorable outcomes or final successful recanalization rates, however, GA may be associated with an increased risk of sICH and mortality.
Rationale:
Mechanical thrombectomy (MT), the standard of care for acute ischemic stroke (AIS) secondary to large vessel occlusion (LVO), is generally not offered to patients with large baseline ...infarct (core). Recent studies demonstrated MT benefit in patients with anterior circulation stroke and large core (i.e. Alberta Stroke Program Early Computed Tomography Score, ASPECTS 3–5). However, its benefit in patients with the largest core (ASPECTS 0–2) remains unproven.
Aim:
To compare the efficacy and safety of MT plus best medical treatment (BMT) and of BMT alone in patients with ASPECTS 0–5 (baseline computed tomography (CT) or magnetic resonance imaging (MRI)) and anterior circulation LVO within 7 h of last-seen-well.
Sample size estimate:
To detect with a two-sided test at 5% significance level (80% power) a common odds ratio of 1.65 for 1-point reduction in the 90-day modified Rankin Scale (mRS) score in the MT + BMT arm versus BMT arm and to anticipate 10% of patients with missing primary endpoint, 450 patients are planned to be included by 36 centers in France, Spain, and the United States.
Methods and design:
LArge Stroke Therapy Evaluation (LASTE) is an international, multicenter, Prospectively Randomized into two parallel (1:1) arms, Open-label, with Blinded Endpoint (PROBE design) trial. Eligibility criteria are diagnosis of AIS within 6.5 h of last-seen-well (or negative fluid-attenuated inversion recovery (FLAIR) if unknown stroke onset time), ASPECTS 0–5 (ASPECTS 4–5 for ⩾80-year-old patients), and LVO in the anterior circulation (intracranial internal carotid artery (ICA) and M1 or M1–M2 segment of the middle cerebral artery (MCA)).
Study outcomes:
The primary endpoint is the day-90 mRS score distribution (shift analysis) with mRS categories 5 and 6 coalesced into one category. Secondary endpoints include day-180 mRS score, rates of 90-day and 180-day mRS score = 0–2 and 0–3, rate of decompressive craniectomy, the National Institutes of Health Stroke Scale (NIHSS) score change, revascularization and infarct volume growth at 24 h, and quality of life at day 90 and 180. Safety outcomes (90-day all-cause mortality, procedural complications, symptomatic intracerebral hemorrhage, and early NIHSS score worsening) are recorded. A dynamic balanced randomization (1:1) is used to distribute eligible patients into the experimental arm and control arm, by incorporating the center and these pre-specified factors: baseline ASPECTS (0–3 vs 4–5), age (⩽70 vs >70 years), baseline NIHSS (<20 vs ⩾20), intravenous thrombolysis (no vs yes), admission mode (Drip-and-Ship vs Mothership), occlusion site (intracranial ICA vs MCA—M1 or M1–M2), intravenous fibrinolysis (no vs yes), and last-seen-well to randomization time (0–4.5 vs >4.5–6.5 h).
Discussion:
The LASTE trial will determine MT efficacy and safety in patients with ASPECTS 0–5 and LVO in the anterior circulation.
Trial registration:
LASTE Trial NCT03811769.
Background and purpose
Although mechanical thrombectomy (MT) appears to be superior in stroke patients with extracranial carotid disease (ECD) compared to thrombolysis alone, the impact of emergent ...carotid stenting during MT remains unclear. The MT outcomes were assessed in anterior stroke patients with ECD, especially when combined with carotid stenting.
Methods
A retrospective analysis of our registry was performed and an update of a systematic review and meta‐analysis of MT studies with or without stenting for anterior circulation stroke with ECD published between November 2010 and April 2017 was conducted.
Results
In our registry, 46 patients with ECD underwent MT. In the meta‐analysis including 13 primary studies plus our prospective registry data (590 patients in total), the successful reperfusion rate (modified thrombolysis in cerebral infarction score ≥2b) reached 75% 95% confidence interval (CI) 69%–81%. The rate of symptomatic intracranial haemorrhage (sICH) was 8% (95% CI 6%–11%), 90‐day favourable outcome was achieved in 50% (95% CI 42%–59%) and mortality rate was 16% (95% CI 11%–22%). When using carotid stenting, rates of successful reperfusion, sICH, 90‐day favourable outcome and mortality were 80% (95% CI 73%–87%), 7% (95% CI 4%–12%), 53% (95% CI 43%–62%) and 14% (95% CI 9%–19%), respectively.
Conclusions
Our data report an association between acute stenting and successful reperfusion rates in stroke patients with tandem lesion treated with MT. Further studies are warranted to determine the intracranial bleeding risk after MT and stenting according to the antiplatelet therapy.
Background and Purpose- Novel endovascular thrombectomy (EVT) devices for acute ischemic stroke are often cleared by regulatory agencies on the basis of noninferiority trials. The relation between ...the noninferiority margins used in trials and the minimal clinically important differences (MCIDs) determined by experts have not been systematically investigated. Methods- Systematic searches were performed to identify (1) all noninferiority design or noninferiority-presented stroke-EVT trials for acute ischemic stroke, (2) all studies determining the MCIDs for the same outcomes, and (3) all noninferiority coronary revascularization trials. Stroke-EVT trial results were reanalyzed using the broad noninferiority margins originally used and narrower noninferiority margins derived from formal MCID studies. Results- We identified 7 noninferiority-designed or noninferiority-interpreted stroke-EVT controlled trials, enrolling 1766 patients, variously comparing coil retrievers, first- and second-generation stent retrievers, and aspiration devices. In 6 trials, the primary outcome was achievement of reperfusion, using noninferiority margins of 15% (3 trials), 10% (2 trials), and 8% (1 trial). In contrast, a stroke expert survey identified the MCID for reperfusion as 3.1% to 5%, and cardiac trials used noninferiority margins of 3.5% to 4.4%. In one stroke-EVT trial, the primary outcome was functional independence, using a noninferiority margin of 15%. However, 2 stroke expert survey studies identified MCIDs for functional independence as having lower values, 5% and 1% to 1.5%. For both reperfusion and functional independence outcomes, all 7 trials demonstrated noninferiority with the broadest noninferiority margin, but only 4 and 3 trials demonstrated noninferiority with actual expert-derived margins for reperfusion and functional independence, respectively. Conclusions- Noninferiority margins used in EVT device trials have regularly exceeded the MCIDs determined by stroke experts, as well as margins used for cardiac devices. New approaches, such as the use of reasonably adequate performance margins, rather than noninferiority margins, are needed to optimize stroke-EVT trial design integrity and trial performance feasibility.
Purpose:
The purpose of this study is to evaluate the safety and efficacy of the mechanical thrombectomy with the Indigo System in the treatment of thrombosed arteriovenous fistulas and grafts.
...Methods:
A retrospective search of endovascular procedures performed from November 2018 to June 2020 was conducted. Inclusion criteria were: acute arteriovenous fistula or graft thrombosis that underwent endovascular mechanical thrombectomy with Indigo System. The following information was collected from each case: sex, age, fistula modality, fistula location, treatment modality, and outcomes. Endpoints evaluated were: technical and clinical success rates; primary, assisted primary, and secondary patency rates; complication rates.
Results:
Twenty-six mechanical thrombectomy procedures for declotting of arteriovenous fistula thrombosis, using the Indigo System, were performed in 22 patients. Technical and clinical success was achieved in 23/26 cases (88%). Mean follow-up was 9 months (range 11–539 days). The 6-month primary, primary assisted, and secondary patency rates were 71%, 86%, 93% and the 12-month primary, primary assisted, and secondary patency rates were 71%, 72%, 80%, respectively. No technical or device-related complications were observed during thrombectomy, however two venous ruptures occurred on the angioplasty of the underlying stenosis.
Conclusion:
In conclusion, vacuum-assisted thrombectomy of acutely thrombosed arteriovenous fistulas and grafts with Indigo System is safe and effective, providing good short term patency rates.
Mechanical thrombectomy is beneficial for patients with acute ischemic stroke and a proximal anterior occlusion, but it is unclear if these results can be extrapolated to patients with an M2 ...occlusion. The purpose of this study was to examine the technical aspects, safety, and outcomes of mechanical thrombectomy with a stent retriever in patients with an isolated M2 occlusion who were included in 3 large multicenter prospective studies.
We included patients from the Solitaire Flow Restoration Thrombectomy for Acute Revascularization (STAR), Solitaire With the Intention For Thrombectomy (SWIFT), and Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME) studies, 3 large multicenter prospective studies on thrombectomy for ischemic stroke. We compared outcomes and technical details of patients with an M2 with those with an M1 occlusion. All patients were treated with a stent retriever. Imaging data and outcomes were scored by an independent core laboratory. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction score of 2b/3.
We included 50 patients with an M2 and 249 patients with an M1 occlusion. Patients with an M2 occlusion were older (mean age, 71 versus 67 years; P = .04) and had a lower NIHSS score (median, 13 versus 17; P < .001) compared with those with an M1 occlusion. Procedural time was nonsignificantly shorter in patients with an M2 occlusion (median, 29 versus 35 minutes; P = .41). The average number of passes with a stent retriever was also nonsignificantly lower in patients with an M2 occlusion (mean, 1.4 versus 1.7; P = .07). There were no significant differences in successful reperfusion (85% versus 82%, P = .82), symptomatic intracerebral hemorrhages (2% versus 2%, P = 1.0), device-related serious adverse events (6% versus 4%, P = .46), or modified Rankin Scale score 0-2 at follow-up (60% versus 56%, P = .64).
Endovascular reperfusion therapy appears to be feasible in selected patients with ischemic stroke and an M2 occlusion.
Elevated systolic blood pressure (SBP) after mechanical thrombectomy (MT) correlates with worse outcome. However, the association between SBP reduction (SBPr) and outcome after successful reperfusion ...with MT is not well established.
To investigate the association between SBPr in the first 24 hours after successful reperfusion and the functional and safety outcomes of MT.
A multicenter retrospective study, which included 10 comprehensive stroke centers, was carried out. Patients with acute ischemic stroke and anterior circulation large vessel occlusions who achieved successful reperfusion via MT were included. SBPr was calculated using the formula 100×(admission SBP-mean SBP/admission SBP). Poor outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 90 days. Safety endpoints included symptomatic intracerebral hemorrhage, mortality, and requirement for hemicraniectomy during admission. A generalized mixed linear model was used to study the association between SBPr and outcomes.
A total of 1361 patients were included in the final analysis. SBPr as a continuous variable was inversely associated with poor outcome (OR=0.97; 95% CI 0.95 to 0.98; p<0.001) but not with the safety outcomes. Subanalysis based on reperfusion status showed that SBPr was associated with lower odds of poor outcome only in patients with complete reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI 3)) but not in patients with incomplete reperfusion (mTICI 2b). When SBPr was divided into categories (<1%, 1%-10%, 11%-20%, >20%), the rate of poor outcome was highest in the first group.
SBPr in the first 24 hours after successful reperfusion was inversely associated with poor outcome. No association between SBPr and safety outcome was found.
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