Thrombectomy for Primary Distal Posterior Cerebral Artery Occlusion Stroke: The TOPMOST Study

Endovascular therapy versus best medical care for acute ischemic stroke with distal medium vessel occlusion: a systematic review and meta-analysis

BACKGROUND

With the refinement of catheter technology, distal medium vessel occlusions (DMVOs) are now viewed as amenable to endovascular treatment (EVT) but its efficacy and safety remains unclear in AIS patients with DMVO.

METHODS

We conducted a systematic search of PubMed, Embase databases and Cochrane Library up to December 2023 using keywords to identify studies comparing EVT versus BMT in AIS with DMVOs. The assessed clinical outcomes were excellent functional outcome, good functional outcome, 90-day mortality, symptomatic intracranial hemorrhage (sICH), and early neurological improvement (ENI) after treatment.

RESULTS

Overall, 31 studies were included. There were no significant differences in excellent functional outcome (OR: 1.21, 95% CI: 0.99-1.47), good functional outcome (OR: 1.03, 95% CI: 0.82-1.30) and 90-day mortality (OR: 1.17, 95% CI: 0.84-1.62). Additionally, EVT led to higher sICH (OR: 1.64, 95% CI: 1.09-2.47) and better ENI (OR: 1.50, 95% CI: 1.02-2.19) compared to BMT. In individuals with M2 occlusion receiving EVT showed better excellent functional outcomes (OR: 1.48, 95% CI: 1.07-2.03). Those patients with PCA occlusion showed no significant difference in functional outcomes. In individuals with ACA occlusion, EVT resulted in reduced functional independence (OR: 0.55, 95% CI: 0.31-0.98). For NIHSS < 6, BMT achieved better functional independence compared to EVT (OR: 0.71, 95% CI: 0.51-0.98) and EVT showed higher sICH (OR: 3.44, 95% CI: 1.42-8.31).

CONCLUSION

For patients with AIS and DMVO occlusion, EVT fails to improve functional prognosis while increasing sICH incidence. More randomized controlled trials are needed in the future to confirm these results.

Trevo 3 Mm and/or AXS Catalyst 5 for the Treatment of Medium Distal Vessel Occlusion Stroke-results from the ASSIST Registry

BACKGROUND

The effect of endovascular therapy (EVT) on the outcome of stroke patients with a medium distal vessel occlusion (MDVO) is unclear. We report the results of MDVO patients treated with the 3 mm Trevo stent retriever (SR) and/or the AXS Catalyst 5 distal access catheter.

METHODS

Data was derived from a prospective, multicenter global registry (ASSIST registry) which enrolled patients treated with operator preferred EVT technique at 71 sites from January 2019 to January 2022. Three techniques were assessed: SR classic, direct aspiration, and a combined approach. Additional inclusion criteria were (a) EVT performed with the 3 mm Trevo SR and/or AXS Catalyst 5 distal access catheter on the first pass and (b) an occlusion of the M2 segment or M3 segment of the middle cerebral artery or the A1, A2 or A3 segment of the anterior cerebral artery. The primary outcome was achieving an expanded Thrombolysis in Cerebral Infarction (eTICI) score of 2c or 3 on the first pass, with the primary technique as adjudicated by core lab. The primary clinical outcome measure was a 90-day modified Rankin Scale (mRS) score of 0-2.

RESULTS

A total of 155 patients (10.4% of the ASSIST population) were included. Most patients had an M2 occlusion (93.5%). First pass eTICI reperfusion was achieved in 43.1% of the patients. No modifying effect of the frontline technique was found. The rate of mRS 0-2 (overall 65.0%) did not significantly differ between groups.

CONCLUSION

The data suggests that the Trevo 3 mm SR and/or the AXS Catalyst 5 may be an option to treat medium distal vessel occlusion, but more data is needed to demonstrate safety and efficacy in this patient cohort. Further improvements are needed regarding materials and techniques to improve reperfusion results in this patient cohort in the future.

High Hypoperfusion Intensity Ratio Is Independently Associated with Very Poor Outcomes in Large Ischemic Core Stroke

BACKGROUND

Recent advances have highlighted the efficacy of endovascular thrombectomy (EVT) in patients with large ischemic core stroke, yet a significant portion still experience very poor outcomes, defined as a 90-day modified Rankin Score (mRS) of 5-6. This study aims to investigate the hypoperfusion intensity ratio (HIR) as a prognostic imaging parameter for these outcomes.

METHODS

In a multicenter retrospective cohort study, data from consecutive patients undergoing EVT for acute ischemic stroke with large vessel occlusion (AIS-LVO) at two comprehensive stroke centers were analyzed. The study included patients with an Alberta Stroke Program Early CT Score (ASPECTS) of 5 or less and utilized pretreatment perfusion imaging to calculate HIR. The primary outcome was very poor outcomes (90 days mRS 5-6).

RESULTS

Among 102 patients included, 59 (57.8%) had very poor outcome (90 days mRS 5-6). Multivariable logistic regression analysis adjusting for multiple covariates including admission National Institutes of Health Stroke Scale (NIHSS) and EVT revealed that higher admission NIHSS (adjusted odds ratio [aOR] 1.224, 95% CI 1.089-1.374, p = 0.001) and HIR (aOR per 0.1 incremental change, 1.34, 95% CI 1.02-1.82, P = 0.042) were independently associated with very poor outcomes.

CONCLUSION

This study demonstrates that admission NIHSS and HIR are independently associated with very poor outcome (90 days mRS 5-6) in patients with large ischemic core strokes. These findings highlight the importance of collateral status and perfusion imaging in predicting outcomes in this patient population, suggesting a potential role for HIR in the triage and management of large core stroke patients.

Mechanical thrombectomy failure in anterior and posterior circulation stroke: current results from a high-volume comprehensive center

BACKGROUND

Mechanical thrombectomy (MT) is an established therapy for acute ischemic stroke (AIS), but recanalization is not always achieved. Common reasons are inadequate removal at the thrombus site and difficulties with the access route. In order to identify risk factors for MT failure we conducted a retrospective study on a high-volume comprehensive stroke center.

METHODS

Evaluation of 552 thrombectomies (2019-23; anterior and posterior circulation, direct aspiration +/- stent retriever [SR]). MT failures (= modified Thrombolysis in Cerebral Infarction score 0 or 1) were analyzed for age, sex, pre- and post-MT modified Rankin Scale, bridging intravenous thrombolysis (IVT), occlusion site (anterior / posterior circulation, proximal / distal), the Kaesmacher classification and time trend results.

RESULTS

MT failure occurred in 56 patients (10.1%; median age 76; 53.6% female). Nineteen (33.9%) patients received IVT (p = 0.326). Logistic regression analysis did not show a significant association of age, sex or occlusion site with MT failure (p = 0.165, p = 0.738, p = 0.838). Distal MT generally demonstrated lower success rates (p < 0.01). According to the Kaesmacher classification SR failure was the most frequent cause of MT failure (category 2B: 48%, p < 0.001). Time trend analysis suggests improving recanalization rates in the further course (4 times in year-on-year comparison; p < 0.01).

CONCLUSION

MT failure occurs in AIS treatment, even in high-volume centers and occurs more frequently in distal occlusions. Improvements in device technology, particularly SR, and ongoing refinements in access route selection offer the prospect of better outcomes in the future.

Efficacy and safety outcomes of endovascular versus best medical treatment in posterior cerebral artery occlusion stroke

BACKGROUND

The management of acute ischemic stroke due to isolated posterior cerebral artery occlusion (iPCAO) remains a topic of debate. This study investigates the efficacy and safety of endovascular treatment (EVT) versus best medical treatment (BMT) in patients with iPCAO.

METHODS

A systematic search was conducted across electronic databases including PubMed, Embase, and the Cochrane Library. Controlled studies comparing EVT and BMT in patients with iPCAO were selected. The primary efficacy outcome assessed was excellent outcome, defined as a modified Rankin Scale (mRS) score of 0-1. The primary safety outcome was symptomatic intracranial hemorrhage (sICH). Secondary outcomes included functional independence (mRS 0-2), early neurological improvement (ENI), and mortality rates. Statistical analyses were conducted using random effects models.

RESULTS

Eleven retrospective cohort studies involving 1811 patients with EVT and 2871 patients with BMT were analyzed. Compared with BMT, EVT was associated with a higher likelihood of an excellent outcome (adjusted OR (aOR) 1.33, 95% CI 1.14 to 1.54) and ENI (aOR 1.66, 95% CI 1.39 to 1.98), but no significant difference in functional independence (aOR 1.02, 95% CI 0.88 to 1.18). Compared with BMT, EVT may not be associated with an increased risk of sICH in patients with iPCAO (aOR 1.34, 95% CI 0.60 to 3.02) or mortality (aOR 1.31, 95% CI 0.83 to 2.08), although heterogeneity was high.

CONCLUSIONS

EVT may improve the likelihood of an excellent outcome and ENI in patients with iPCAO. However, the potential risks of sICH and mortality warrant consideration. Randomized trials are required to establish the definitive efficacy and safety of EVT in this patient population.

Clinical outcomes of patients with unsuccessful mechanical thrombectomy versus best medical management of medium vessel occlusion stroke in the middle cerebral artery territory

BACKGROUND

Current randomized controlled trials are investigating the efficacy and safety of mechanical thrombectomy (MT) in patients with medium vessel occlusion (MeVO) stroke. Whether best medical management (MM) is more efficient than unsuccessful vessel recanalization during MT remains unknown.

METHODS

This was a retrospective cohort study using data from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. Only patients with occlusion of the distal branches (M2 and M3) of the middle cerebral artery territory were included. Unsuccessful MT was defined as a modified Thrombolysis in Cerebral Infarction score of 0-2a. Propensity score matching was used to control for confounders. The primary outcome was functional independence, defined as a modified Rankin Scale (mRS) score of 0-2 at 90 days after treatment. Multivariable regression analysis was used to assess factors associated with the primary outcome.

RESULTS

Of 2903 patients screened for eligibility, 532 patients were analyzed (266 per group) after propensity score matching. The MM group had superior functional outcomes, with 32% achieving mRS 0-1 at 90 days compared with 21% in the MT group (P=0.011). Patients in the MM group also had significantly lower rates of symptomatic intracranial hemorrhage (sICH) (3.4% vs 16%, P<0.001) and any hemorrhage (18% vs 48%, P<0.001). On multivariable regression, unsuccessful MT was associated with reduced odds of functional independence (OR 0.50, 95% CI 0.29 to 0.85, P=0.011) and increased odds of sICH (OR 4.32, 95% CI 1.84 to 10.10, P<0.001). Mortality rates were similar between groups (27% in MM vs 29% in MT, P=0.73).

CONCLUSION

Unsuccessful MT for MeVO was linked to worse outcomes than best MM. These findings highlight the risks of prolonged attempts and emphasize the importance of efficient procedural decision-making to reduce complications and improve patient outcomes.

Endovascular thrombectomy for distal medium vessel occlusions: A literature review

BACKGROUND

There is a lack of substantial evidence supporting the safety and effectiveness of endovascular thrombectomy in treating distal medium vessel occlusions (DMVOs).

OBJECTIVE

To summarize the current evidence regarding endovascular thrombectomy for DMVOs.

METHODS

We conducted a narrative review of key articles related to the diagnosis and management of DMVOs. We manually searched PubMed and Google Scholar from January 2010 to July 2023, and only included articles published in the English language.

RESULTS

While diagnosing and treating DMVOs is tricky due to access limitations and potential limited benefit from mechanical clot removal, recent improvements in catheter and retrieval technology suggest that endovascular thrombectomy might be a potential treatment option. However, more high-quality research is needed to confirm its effectiveness for DMVOs.

CONCLUSION

Experts disagree on how to classify DMVOs and what the best mode of endovascular treatment is.

EnDovascular therapy plus best medical treatment (BMT) versus BMT alone for medIum distal veSsel occlusion sTroke (DISTAL): An international, multicentre, randomized-controlled, two-arm, assessor-blinded trial

RATIONALE

Whether endovascular therapy (EVT) in addition to best medical treatment (BMT) in people with acute ischemic stroke (AIS) due to a medium distal vessel occlusion (MDVO) is beneficial remains unclear.

AIM

To determine if people experiencing an AIS due to an isolated MDVO (defined as the co- or non-dominant M2 segment, the M3 or M4 segment of the middle cerebral artery, the A1, A2, or A3 segment of the anterior cerebral artery or the P1, P2 or P3 segment of the posterior cerebral artery) will have superior outcome if treated with EVT in addition to BMT compared to BMT alone.

SAMPLE SIZE

To randomize 526 participants 1:1 to EVT plus BMT or BMT alone.

METHODS AND DESIGN

A multicentre, international, prospective, randomized, open-label, blinded-endpoint (PROBE) superiority trial.

OUTCOMES

The primary efficacy endpoint is the distribution of disability levels on the modified Rankin Scale at 90 days. Secondary clinical efficacy outcomes include normalized change in National Institutes of Health Stroke Scale score from baseline to day 1, cognitive outcome at 90 days, and health-related quality of life at 90 days. Safety outcomes include all serious adverse events, symptomatic intracranial hemorrhage within 24 h, and all-cause mortality up to 90 days. Secondary imaging outcomes include successful reperfusion at end of EVT procedure and recanalization of target artery at 24 h.

DISCUSSION

DISTAL will inform physicians whether EVT in addition to BMT in people with AIS due to a MDVO is more efficacious than BMT alone.

Pretreatment predictors of very poor clinical outcomes in medium vessel occlusion stroke patients treated with mechanical thrombectomy

BACKGROUND

Acute ischemic stroke (AIS) from primary medium vessel occlusions (MeVO) is a prevalent condition associated with substantial morbidity and mortality. Despite the common use of mechanical thrombectomy (MT) in AIS, predictors of poor outcomes in MeVO remain poorly characterized.

METHODS

In this prospectively collected, retrospectively reviewed, multicenter, multinational study, data from the MAD-MT (Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy) registry were analyzed. The study included 1568 patients from 37 academic centers across North America, Asia, and Europe, treated with MT, with or without intravenous tissue plasminogen activator (IVtPA), between September 2017 and July 2021.

RESULTS

Among the 1568 patients, 347 (22.2%) experienced very poor outcomes (modified Rankin score (mRS), 5-6). Key predictors of poor outcomes were advanced age (odds ratio (OR): 1.03; 95% confidence interval (CI): 1.02 to 1.04; p < 0.001), higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (OR: 1.07; 95% CI: 1.05 to 1.10; p < 0.001), pre-operative glucose levels (OR: 1.01; 95% CI: 1.00 to 1.02; p < 0.001), and a baseline mRS of 4 (OR: 2.69; 95% CI: 1.25 to 5.82; p = 0.011). The multivariable model demonstrated good predictive accuracy with an area under the receiver-operating characteristic (ROC) curve of 0.76.

CONCLUSIONS

This study demonstrates that advanced age, higher NIHSS scores, elevated pre-stroke mRS, and pre-operative glucose levels significantly predict very poor outcomes in AIS-MeVO patients who received MT. These findings highlight the importance of a comprehensive risk assessment in primary MeVO patients for personalized treatment strategies. However, they also suggest a need for cautious patient selection for endovascular thrombectomy. Further prospective studies are needed to confirm these findings and explore targeted therapeutic interventions.

Vessel deviation during stent retrieval predicts successful recanalization in stent-based mechanical thrombectomy for M2 occlusion

PURPOSE

This study aimed to clarify whether there is a relationship between vessel deviation during stent retrieval and successful recanalization in stent-based mechanical thrombectomy (MT) for M2 occlusion.

METHODS

The video of the MT was reviewed for each of the 25 included patients with M2 occlusion. The vertical distance of vessel deviation at the time of stent retrieval was defined as D, and the diameter of the balloon guide catheter shown on the same screen was defined as B. The D/B ratio was calculated as an index of the vessel deviation. The presence or absence of successful recanalization (thrombolysis in cerebral infarction (TICI) score of 2b/3) was compared based on the D/B ratio and clinical factors.

RESULTS

Of the 25 patients, successful recanalization was achieved in 18 (72%). The median D/B ratio with successful recanalization was 0.9, which was significantly lower than that without successful recanalization (2.5, p < 0.001, Mann-Whitney U test). Combined aspiration catheters were used in 24 cases. In nine (36%) cases, the tip of the aspiration catheter was in M2 during stent retrieval. The median D/B ratio with the position of the aspiration catheter tip in M1 or the internal carotid artery was 1.5, which was significantly higher than that with the position in M2 (0, p = 0.003, Mann-Whitney U test).

CONCLUSION

In stent-based MT for M2 occlusion, cases in which successful recanalization was achieved showed less vessel deviation during stent retrieval. To reduce vessel deviation, advancing the combined aspiration catheter up to M2 is useful.

Mechanical thrombectomy for the treatment of primary and secondary anterior cerebral artery occlusions: insights from STAR

BACKGROUND

The safety and efficacy of mechanical thrombectomy (MT) for the treatment of acute anterior cerebral artery (ACA) occlusions have not clearly been delineated. Outcomes may be impacted based on whether the occlusion is isolated to the ACA (primary ACA occlusion) or occurs in conjunction with other cerebral arteries (secondary).

METHODS

We performed a retrospective review of the multicenter Stroke Thrombectomy and Aneurysm (STAR) database. All patients with MT-treated primary or secondary ACA occlusions were included. Baseline characteristics, procedural outcomes, complications, and clinical outcomes were collected. Primary and secondary ACA occlusions were compared using the Mann-Whitney U test and Kruskal-Willis test for continuous variables and the χ2 test for categorical variables.

RESULTS

The study cohort comprised 238 patients with ACA occlusions (49.2% female, median (SD) age 65.6 (16.7) years). The overall rate of successful recanalization was 75%, 90-day good functional outcome was 23%, and 90-day mortality was 35%. There were 44 patients with a primary ACA occlusion and 194 patients with a secondary ACA occlusion. When adjusted for baseline variables, the rates of successful recanalization (68% vs 76%, P=0.27), 90-day good functional outcome (41% vs 19%, P=0.38), and mortality at 90 days (25% vs 38%, P=0.12) did not differ between primary and secondary ACA occlusion groups.

CONCLUSION

Clinical and procedural outcomes are similar between MT-treated primary and secondary ACA occlusions for select patients. Our findings demonstrate the need for established criteria to determine ideal patient and ACA stroke characteristics amenable to MT treatment.

Perfusion imaging predicts short-term clinical outcome in isolated posterior cerebral artery occlusion stroke

BACKGROUND AND PURPOSE

Ischemic strokes due to isolated posterior cerebral artery (PCA) occlusions represent 5% of all strokes but have significant impacts on patients' quality of life, primarily due to visual deficits and thalamic involvement. Current guidelines for acute PCA occlusion management are sparse, and the prognostic value of perfusion imaging parameters remains underexplored.

METHODS

We conducted a retrospective analysis of 32 patients with isolated PCA occlusions treated at Johns Hopkins Medical Institutions between January 2017 and March 2023. Patients underwent pretreatment perfusion imaging, with perfusion parameters analyzed using RAPID software. The primary outcome was short-term clinical outcome as measured by the National Institutes of Health Stroke Scale (NIHSS) at discharge.

RESULTS

The median age of the cohort was 70 years, with 34% female and 66% male. Significant correlations were found between NIHSS at discharge and various perfusion parameters, including time-to-maximum (Tmax) >6 seconds (ρ = .55, p = .004), Tmax >8 seconds (ρ = .59, p = .002), Tmax >10 seconds (ρ = .6, p = .001), mismatch volume (ρ = .51, p = .008), and cerebral blood volume (CBV) < 34% (ρ = .59, p = .002).

CONCLUSIONS

Tmax and CBV volumes significantly correlated with discharge NIHSS with marginal superiority of Tmax >10 seconds and CBV <42% volumes. These findings suggest that CT and MR perfusion imaging can play a crucial role in the acute management of PCA strokes, though larger, standardized studies are needed to validate these results and refine imaging thresholds specific to posterior circulation infarcts.

Efficacy and safety of thrombectomy with or without intravenous thrombolysis in the treatment of acute basilar artery occlusion ischemic stroke: an updated systematic review and meta-analysis

Background

Mechanical thrombectomy (MT) is a well-established treatment for acute basilar artery occlusion (BAO)-induced posterior circulation ischemic stroke.

Objective

The objective of the study was to compare the outcomes of endovascular therapy (EVT) with and without bridging intravenous thrombolysis (IVT) in patients with acute BAO, using an updated meta-analysis.

Methods

A systematic literature search was conducted to identify studies that compared the efficacy and safety of EVT with and without IVT in the treatment of acute BAO ischemic stroke. The extracted data included sample size, patient age, National Institutes of Health Stroke Scale (NIHSS) scores, 90-day modified Rankin Scale (mRS) scores of 0-2 and 0-3, mortality rates, symptomatic intracranial hemorrhage (sICH), and occurrence of subarachnoid hemorrhage (SAH).

Results

Five studies that included a total of 1,578 patients (594 IVT + EVT vs. 984 EVT), met the inclusion criteria and were analyzed. The meta-analysis demonstrated that bridging IVT was associated with a higher likelihood of achieving a 90-day mRS score of 0-2 (41% vs. 34%; OR = 1.35, 95% CI 1.09-1.68, p = 0.006). Furthermore, the mortality rate was significantly lower in the IVT + EVT group than in the direct EVT group (25% vs. 30%; OR = 0.70, 95% CI 0.55-0.89, p = 0.003), with low heterogeneity observed (I 2 = 0.0%, p = 0.78). However, there were no significant differences between the groups regarding the rates of sICH (5% vs. 6%; OR = 0.85, 95% CI: 0.52-1.39, p = 0.53), SAH (3% vs. 3%; OR = 0.93, 95% CI: 0.39-2.22, p = 0.87), perforation (2% vs. 3%; OR = 0.71, 95% CI 0.26-1.95, p = 0.51), and dissection (3% vs. 2%; OR = 0.97, 95% CI: 0.13-7.14, p = 0.98).

Conclusion

Bridging IVT in conjunction with EVT was associated with better functional outcomes and reduced mortality rates in patients with acute ischemic stroke (AIS) due to BAO compared to EVT alone, without an increased risk of sICH, SAH, perforation, and dissection. In addition, the benefit of bridging IVT to EVT appeared to be more pronounced in European patients than in Asian patients compared to EVT alone. However, the conclusions of this study are not definitive and require validation through large-scale randomized controlled trials (RCTs) to draw more robust conclusions.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024531363.

Endovascular therapy versus medical management in isolated posterior cerebral artery acute ischemic stroke: A multinational multicenter propensity score-weighted study

BACKGROUND

Despite the proven effectiveness of endovascular therapy (EVT) in acute ischemic strokes (AIS) involving anterior circulation large vessel occlusions, isolated posterior cerebral artery (PCA) occlusions (iPCAo) remain underexplored in clinical trials. This study investigates the comparative effectiveness and safety of EVT against medical management (MM) in patients with iPCAo.

METHODS

This multinational, multicenter propensity score-weighted study analyzed data from the Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy (MAD-MT) registry, involving 37 centers across North America, Asia, and Europe. We included iPCAo patients treated with either EVT or MM. The primary outcome was the modified Rankin Scale (mRS) at 90 days, with secondary outcomes including functional independence, mortality, and safety profiles such as hemorrhagic complications.

RESULTS

A total of 177 patients were analyzed (88 MM and 89 EVT). EVT showed a statistically significant improvement in 90-day mRS scores (OR = 0.55, 95% CI = 0.30-1.00, p = 0.048), functional independence (OR = 2.52, 95% CI = 1.02-6.20, p = 0.045), and a reduction in 90-day mortality (OR = 0.12, 95% CI = 0.03-0.54, p = 0.006) compared to MM. Hemorrhagic complications were not significantly different between the groups.

CONCLUSION

EVT for iPCAo is associated with better neurological outcomes and lower mortality compared to MM, without an increased risk of hemorrhagic complications. Nevertheless, these results should be interpreted with caution due to the study's observational design. The findings are hypothesis-generating and highlight the need for future randomized controlled trials to confirm these observations and establish definitive treatment guidelines for this patient population.

The Vecta 46 intermediate catheter for mechanical thrombectomy of distal medium vessel occlusions: A single-center experience

INTRODUCTION

With emerging evidence supporting the clinical efficacy and safety of mechanical thrombectomy (MT) for distal medium vessel occlusions (DMVOs), MT devices specifically designed to navigate through smaller caliber and more delicate tortuous distal cerebrovasculature are required. This study describes our single-center experience using the AXS Vecta 46 intermediate catheter for first-line thromboaspiration of DMVOs.

METHODS

We identified all patients who underwent MT using the Vecta 46 for first-line thromboaspiration for primary or secondary DMVOs. We collected baseline clinical data, angiographic and clinical outcomes, as well as procedural complications. The primary outcome in question was the rate of successful recanalization, which was defined as a modified Thrombolysis in Cerebral Infarction score of ≥2b.

RESULTS

We identified 43 patients who underwent MT using the Vecta 46 catheter for thromboaspiration of 54 DMVOs. Intervened vessels included the M2 (23/54), M3 (19/54), and M4 (6/54) branches of the middle cerebral artery, A2 (1/54), A3 (1/54), and A4 (1/54) branches of the anterior cerebral artery, and P1 (1/54), P2 (1/54), and P4 (1/54) branches of the posterior cerebral artery. The median number of passes for primary DMVOs was 2 (IQR: 1-3) and 1 (IQR: 1-1.25) for secondary DMVOs. The rate of successful recanalization was 100% (18/18) for primary DMVOs and 80.6% (29/36) for secondary DMVOs. First-pass effect (FPE) was noted in 55.6% (30/54) of all primary and secondary DMVO cases. Improved short-term clinical outcomes were observed in both the primary (National Institute of Health Stroke Scale [NIHSS] shift: -5 [IQR: -14.25 to -0.25]) and secondary (NIHSS shift: -5 [IQR: -10 to -2]) DMVO groups. A total of six patients died during their hospitalization, though none were deemed procedural-related.

CONCLUSIONS

Our study demonstrates the safety and efficacy of the Vecta 46 intermediate catheter for thromboaspiration of both primary and secondary DMVOs, achieving high rates of successful recanalization and FPE.

Derivation and validation of a predictive scale to expedite endovascular intervention for acute stroke patients with an intervenable vessel occlusion

BACKGROUND

Early endovascular intervention team mobilization may reduce reperfusion times and improve clinical outcomes for patients with acute ischemic stroke (AIS) with a possible intervenable vessel occlusion (IVO). In an emergency department or mobile stroke unit, incorporating rapidly available non-contrast CT (NCCT) information with examination findings may improve the accuracy of arterial occlusion prediction scales. For this purpose, we developed a rapid and straightforward IVO predictive instrument-the T3AM2PA1 scale.

METHODS

The T3AM2PA1 scale was retrospectively derived from our 'Get with the Guidelines' database. We included all patients with acute stroke alert between January 2017 and August 2018 with a National Institutes of Health Stroke Scale (NIHSS) score between 5 and 25 inclusive. Different pre-intervention variables were collected, including itemized NIHSS and NCCT information. The T3AM2PA1 scale was also compared with other commonly used scales and was validated in a separate sequential retrospective cohort of patients with a full range of NIHSS scores.

RESULTS

574 eligible patients from 2115 acute stroke alerts were identified. The scale was established with five items (CT hyperdense sign, parenchymal hypodensity, lateralizing hemiparesis, gaze deviation, and language disturbance), with a total score of 9. To minimize unnecessary angiography, a cut-off of ≥5 for IVO detection yielded a sensitivity of 52%, a specificity of 90%, and a positive predictive value of 76%.

CONCLUSIONS

The T3AM2PA1 scale accurately predicts the presence of clinical IVO in patients with AIS. Adopting the T3AM2PA1 scale could reduce revascularization times, improve treatment outcomes, and potentially reduce disability.

Endovascular thrombectomy versus medical management for moderate-to-severe anterior cerebral artery occlusion stroke

BACKGROUND

There are no established patient selection criteria for endovascular thrombectomy (EVT) for anterior cerebral artery (ACA) stroke.

METHODS

This was a retrospective cohort study of the 2016-2020 National Inpatient Sample in the United States. Isolated ACA-occlusion stroke patients with moderate-to-severe stroke symptoms (NIH stroke scale [NIHSS] ≥ 6) were included. Primary outcome was hospital discharge to home with self-care. Secondary outcomes include in-hospital mortality and intracranial hemorrhage (ICH). Confounders were accounted for by multivariable logistic regression.

RESULTS

6685 patients were included; 335 received EVT. Compared to medical management (MM), EVT patients were younger (mean 67.2 versus 72.2 years; p = 0.014) and had higher NIHSS (mean 16.0 versus 12.5; p < 0.001). EVT was numerically but not statistically significantly associated with higher odds of home discharge compared to MM (aOR 2.26 [95%CI 0.99-5.17], p = 0.053). EVT was significantly associated with higher odds of home discharge among patients with NIHSS 10 or greater (aOR 3.35 [95%CI 1.06-10.58], p = 0.039), those who did not receive prior thrombolysis (aOR 3.96 [95%CI 1.53-10.23], p = 0.005), and those with embolic stroke etiology (aOR 4.03 [95%CI 1.21-13.47], p = 0.024). EVT was not significantly associated with higher rates of mortality (aOR 1.93 [95%CI 0.80-4.63], p = 0.14); however, it was significantly associated with higher rates of ICH (22.4% vs. 8.5%, p < 0.001).

CONCLUSION

EVT was associated with higher odds of favorable short-term outcomes for moderate-to-severe ACA-occlusion stroke in select patients. Future studies are needed to confirm the efficacy of EVT in terms of longer term neurological outcomes.

Multicenter evaluation of mechanical thrombectomy for distal medium vessel occlusions with National Institute of Health Stroke Scale Scores ≥ 6 and ≤ 6

BACKGROUND

While mechanical thrombectomy is considered standard of care for large vessel occlusions, scientific evidence to support treatment for distal and medium vessel occlusions remains scarce.

PURPOSE

To evaluate feasibility, safety, and outcomes in patients with low National Institute of Health Stroke Scale scores undergoing mechanical thrombectomy for treatment of distal medium vessel occlusions.

MATERIALS AND METHODS

Retrospective data review and analysis of prospectively maintained databases at 41 academic centers in North America, Asia, and Europe between January 2017 and January 2022. Characteristics and outcomes were compared between groups with low stroke scale score (≤ 6) versus and higher stroke scale scores (> 6). Propensity score matching using the optimal pair matching method and 1:1 ratio was performed.

RESULTS

Data were collected on a total of 1068 patients. After propensity score matching, there were a total of 676 patients included in the final analysis, with 338 patients in each group. High successful reperfusion rates were seen in both groups, 90.2% in ≤ 6 and 88.7% in the > 6 stroke scale groups. The frequency of excellent and good functional outcome was seen more common in low versus higher stroke scale score patients (64.5% and 81.1% versus 39.3% and 58.6%, respectively). The 90-day mortality rate observed in the ≤ 6 stroke scale group was 5.3% versus 13.3% in the > 6 stroke scale group.

CONCLUSION

Mechanical thrombectomy in distal and medium vessel occlusions, specifically in patients with low stroke scale scores is feasible, though it may not necessarily improve outcomes over IVT.

Combining the deployment of only the distal basket segment of the EMBOTRAP III and an aspiration catheter for M2 occlusions: the ONE-SEG technique

Background

Endovascular therapy (EVT) for distal medium vessel occlusions requires prioritizing effectiveness and safety. We developed a technique combining the deployment of only the distal basket segment of the EMBOTRAP III and an aspiration catheter (AC) for M2 occlusions, called the "ONE-SEG technique," and evaluated its clinical and technical impacts.

Methods

This was a retrospective review of 30 consecutive patients with M2 segment middle cerebral artery occlusion treated using the ONE-SEG technique. This method involves deploying the EMBOTRAP III through a microcatheter in only one segment and guiding the AC to the M2 origin or distal M1. The rates of final-pass expanded thrombolysis in cerebral infarction (eTICI) scores of 2c/3 or 2b/2c/3, safety (symptomatic intracranial hemorrhage [sICH]), and clinical outcomes (modified Rankin Scale [mRS] score 0-2, 0-3 at 90 days, and mortality at 90 days) were evaluated.

Results

Of the 30 cases, 36.7% were female, and the mean age was 75.6 ± 11.0 years. The ONE-SEG technique was used for 17 cases (56.7%, median NIHSS 10 [5-15.5]) with primary M2 occlusion and 13 cases (43.3%, median NIHSS 20 [14-22.5]) with secondary M2 occlusion after proximal thrombus removal. The successful final reperfusion rate (eTICI 2b/2c/3) was 90% overall (27/30 cases). One case (3.3%) developed sICH with secondary M2 occlusion. At 3 months, mRS scores 0-2 were seen in 64.7% of patients with primary M2 occlusion (11/17 cases) and in 23.1% (3/13 cases) with secondary M2 occlusion.

Conclusion

EVT using the ONE-SEG technique appears to be safe and effective for M2 occlusion.

Post-Thrombectomy Subarachnoid Hemorrhage: Incidence, Predictors, Clinical Relevance, and Effect Modulators

BACKGROUND

Subarachnoid hemorrhage (SAH) following endovascular thrombectomy (EVT) is a poorly understood phenomenon, and whether it is associated with clinical detriment is unclear.

METHODS

This was an explorative analysis of a national database of real-world hospitalizations in the United States. Patients who underwent EVT were included. Patients were divided into SAH and non-SAH groups, and hospitalization outcomes were compared using multivariable logistic regression models. Regression models were also used to identify significant predictors for post-EVT SAH, and significant modulators of SAH's association with hospitalization outcomes were also assessed.

RESULTS

A total of 99,219 EVT patients were identified; 6174 (6.2%) had SAH. Overall, SAH was independently associated with increased odds of in-hospital mortality (21.5% vs. 10.6%, adjusted OR 2.53 [95%CI 2.23-2.87], p < 0.001) and lower odds of routine discharge to home with self-care (18.2% vs. 28.0%, aOR 0.58 [95%CI 0.52-0.65], p < 0.001). Distal/medium vessel occlusion (DMVO), coagulopathy, angioplasty or stenting, concurrent intraparenchymal hemorrhage (IPH), and female sex were associated with higher odds of SAH. DMVO was associated with particularly heightened risk of death (31.8% vs. 7.9%, aOR 6.99 [95%CI 2.99 to 16.3], p < 0.001), which was an effect size significantly larger than other sites of vascular occlusion (interaction p > 0.05).

CONCLUSION

SAH is an uncommon but likely clinically detrimental post-EVT complication. DMVO, coagulopathy, angioplasty or stenting, concurrent IPH, and female sex were independently associated with higher odds of post-EVT SAH. SAH associated with DMVO-EVT may be particularly harmful.

Endovascular therapy of isolated posterior cerebral artery occlusion stroke with and without general anesthesia

BACKGROUND

The optimal anesthetic strategy for endovascular therapy (EVT) in acute ischemic stroke is still under debate. The aim of this study was to compare the clinical outcomes of patients with isolated posterior cerebral artery (PCA) occlusion stroke undergoing EVT by anesthesia modality with conscious sedation (non-GA) versus general anesthesia (GA).

METHODS

Patients from the Posterior CerebraL Artery Occlusion (PLATO) study were analyzed with regard to anesthetic strategy. GA was compared with non-GA using multivariable logistic regression and inverse probability of weighting treatment (IPTW) methods. The primary endpoint was the 90-day distribution of the modified Rankin Scale (mRS) score. Secondary outcomes included functional independence or return to Rankin at day 90, and successful reperfusion, defined as expanded Thrombolysis in Cerebral Infarction (eTICI) 2b to 3. Safety endpoints were symptomatic intracranial hemorrhage and mortality.

RESULTS

Among 376 patients with isolated PCA occlusion stroke treated with EVT, 183 (49%) had GA. The treatment groups were comparable, although the GA group contained more patients with severe stroke and lower posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS). On IPTW analysis, there was no difference between groups with regard to ordinal mRS shift analysis (common OR 0.89, 95% CI 0.53 to 1.51, P=0.67) or functional independence (OR 0.84, 95% CI 0.50 to 1.39, P=0.49). There were greater odds for successful reperfusion with GA (OR 1.70, 95% CI 1.17 to 2.47, P=0.01). Safety outcomes were comparable between groups.

CONCLUSION

In patients with isolated PCA occlusion undergoing EVT, patients treated with GA had higher reperfusion rates compared with non-GA. Both GA and non-GA strategies were safe and functional outcomes were similar.

Clinical and radiographic outcomes after mechanical thrombectomy in medium-vessel posterior cerebral artery occlusions: Subgroup analysis from STAR

BACKGROUND

Whereas mechanical thrombectomy (MT) has become standard-of-care treatment for patients with salvageable brain tissue after acute stroke caused by large-vessel occlusions, the results of MT in patients with medium-vessel occlusions (MEVOs), particularly in the posterior cerebral artery (PCA), are not well known.

METHODS

Using data from the international Stroke Thrombectomy and Aneurysm Registry (STAR), we assessed presenting characteristics and clinical outcomes for patients who underwent MT for primary occlusions in the P2 PCA segment. As a subanalysis, we compared the PCA MeVO outcomes with STAR's anterior circulation MeVO outcomes, namely middle cerebral artery (MCA) M2 and M3 segments.

RESULTS

Of the 9812 patients in STAR, 43 underwent MT for isolated PCA MeVOs. The patients' median age was 69 years (interquartile range 61-79), and 48.8% were female. The median NIH Stroke Scale score was 9 (range 6-17). After recanalization, 67.4% of patients achieved successful recanalization (modified treatment in cerebral infarction score [mTICI] ≥ 2b), with a first-pass success rate of 44.2%, and 39.6% achieved a modified Rankin score of 0-2 at 90 days. Nine patients (20.9%) had died by the 90-day follow-up. In comparison with M2 and M3 MeVOs, there were no differences in presenting characteristics among the three groups. Patients with PCA MeVOs were less likely to undergo intra-arterial thrombolysis (4.7% PCA vs. 10.1% M2 vs. 16.2% M3, p = 0.046) or to achieve successful recanalization (mTICI ≥ 2b, 67.4%, 86.7%, 82.3%, respectively, p < 0.001); however, there were no differences in the rates of successful first-pass recanalization (44.2%, 49.8%, 52.3%, respectively, p = 0.65).

CONCLUSIONS

We describe the STAR experience performing MT in patients with PCA MeVOs. Our analysis supports that successful first-pass recanalization can be achieved in PCA MEVOs at a rate similar to that in MCA MeVOs, although further study and possible innovation may be necessary to improve successful PCA MeVO recanalization rates.

Meta-analysis of clinical and safety profiles after reperfusion therapy in acute posterior circulation strokes: insights and implications

BACKGROUND

Posterior circulation stroke (PCS) accounts for approximately 20% of all acute ischemic strokes. The optimal reperfusion therapy for PCS management remains uncertain.

PURPOSE

To evaluate the prevalence and outcomes of intravenous thrombolysis (IVT), endovascular thrombectomy (EVT), and bridging therapy in PCS patients.

MATERIAL AND METHODS

We conducted a meta-analysis of 19 studies examining reperfusion therapy outcomes in PCS patients, including 9765 individuals. We pooled prevalence data and assessed associations between reperfusion therapies and clinical, safety, and recanalization outcomes using random-effects models.

RESULTS

The pooled prevalence of reperfusion therapies post-acute PCS was 39% for IVT, 54% for EVT, and 48% for bridging therapy. EVT was associated with significantly higher odds of favorable functional outcomes (modified Rankin Score [mRS] 0-3) at 90 days compared to standard medical therapy (odds ratio [OR] = 5.68; 95% confidence interval [CI]=2.07-15.59; P = 0.001). Conversely, bridging therapy was linked to reduced odds of favorable functional outcomes at 90 days compared to EVT (OR = 0.35; 95% CI=0.26-0.47; P < 0.001). Bridging therapy was also significantly associated with lower odds of good functional outcomes (mRS 0-2) (OR = 0.25; 95% CI=0.11-0.54; P < 0.001), reduced risk of symptomatic intracranial hemorrhage (OR = 0.26; 95% CI=0.07-0.68; P = 0.009), lower mortality (OR = 0.13; 95% CI=0.04-0.44; P = 0.001), and less successful recanalization (OR = 0.35; 95% CI=0.13-0.94; P = 0.038) relative to EVT.

CONCLUSION

Our meta-analysis underscores the favorable outcomes associated with EVT in PCS cases. With notable reperfusion rates, understanding factors influencing PCS outcomes can inform patient selection and prognostic considerations.

Endovascular Versus Medical Therapy in Posterior Cerebral Artery Stroke: Role of Baseline NIHSS Score and Occlusion Site

BACKGROUND

Acute ischemic stroke with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO acute ischemic stroke is modified by initial stroke severity (baseline National Institutes of Health Stroke Scale [NIHSS]) and arterial occlusion site.

METHODS

Based on the multicenter, retrospective, case-control study of consecutive iPCAO acute ischemic stroke patients (PLATO study [Posterior Cerebral Artery Occlusion Stroke]), we assessed the heterogeneity of EVT outcomes compared with medical management (MM) for iPCAO, according to baseline NIHSS score (≤6 versus >6) and occlusion site (P1 versus P2), using multivariable regression modeling with interaction terms. The primary outcome was the favorable shift of 3-month modified Rankin Scale (mRS). Secondary outcomes included excellent outcome (mRS score 0-1), functional independence (mRS score 0-2), symptomatic intracranial hemorrhage, and mortality.

RESULTS

From 1344 patients assessed for eligibility, 1059 were included (median age, 74 years; 43.7% women; 41.3% had intravenous thrombolysis): 364 receiving EVT and 695 receiving MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (Pinteraction=0.312) but did with functional independence (Pinteraction=0.010), with a similar trend on excellent outcome (Pinteraction=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS score >6 (mRS score 0-1, 30.6% versus 17.7%; adjusted odds ratio [aOR], 2.01 [95% CI, 1.22-3.31]; mRS score 0 to 2, 46.1% versus 31.9%; aOR, 1.64 [95% CI, 1.08-2.51]) but not in those with NIHSS score ≤6 (mRS score 0-1, 43.8% versus 46.3%; aOR, 0.90 [95% CI, 0.49-1.64]; mRS score 0-2, 65.3% versus 74.3%; aOR, 0.55 [95% CI, 0.30-1.0]). EVT was associated with more symptomatic intracranial hemorrhage regardless of baseline NIHSS score (Pinteraction=0.467), while the mortality increase was more pronounced in patients with NIHSS score ≤6 (Pinteraction=0.044; NIHSS score ≤6: aOR, 7.95 [95% CI, 3.11-20.28]; NIHSS score >6: aOR, 1.98 [95% CI, 1.08-3.65]). Arterial occlusion site did not modify the association of EVT with outcomes compared with MM.

CONCLUSIONS

Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS score >6) had more favorable disability outcomes with EVT than MM, despite increased mortality and symptomatic intracranial hemorrhage.

Feasibility and Clinical Outcome Predictors of Mechanical Thrombectomy in Distal Arterial Occlusion Causing Acute Ischemic Stroke: A Monocentric Retrospective Study

BACKGROUND

The feasibility and clinical outcome predictors of mechanical thrombectomy (MT) for strokes caused by distal arterial occlusion (DAO) remain the subject of debate.

METHODS

A retrospective analysis was conducted of patients with consecutive acute ischemic stroke treated using MT. Clinical and procedural-associated factors were studied to compare the efficacy, safety, and short-term and long-term outcomes of MT between the proximal arterial occlusion (PAO) and DAO groups. The predictors of a good functional outcome in the DAO group were also identified.

RESULTS

A total of 116 patients were included in this study, of whom 23 (19.8%) underwent MT for DAO. A higher complete recanalization rate was independently associated with PAO in adjusted models [adjusted odds ratio, 0.596; 95% CI, 0.377-0.941]. The measures of safety and clinical outcome showed no significant differences between the DAO and PAO groups. The National Institute of Health stroke scale (NIHSS) score on admission, hybrid technique use, and complete recanalization rate emerged as independent predictors of a good functional outcome in the DAO group.

CONCLUSIONS

The efficacy, safety, and short-term and long-term outcomes of DAO thrombectomy were similar to those of PAO thrombectomy. The good functional outcome predictors of MT in DAO included NIHSS on admission, hybrid technique use, and complete recanalization. Overall, the findings lead us to propose that MT may be considered a feasible option for treating DAO after a careful risk-benefit analysis.

Derivation and Validation of a Scoring System for Predicting Poor Outcome After Posterior Circulation Ischemic Stroke in China

BACKGROUND AND OBJECTIVES

Guidelines for posterior circulation ischemic stroke (PCIS) treatment are lacking and outcome prediction is crucial for patients and clinicians. We aimed to develop and validate a prognostic score to predict the poor outcome for patients with PCIS.

METHODS

The score was developed from a prospective derivation cohort named the Third China National Stroke Registry (August 2015-March 2018) and validated in a spatiotemporal independent validation cohort (December 2017-March 2023) in China. Patients with PCIS with acute infarctions defined as hyperintense lesions on diffusion-weighted imaging were included in this study. The poor outcome was measured as modified Rankin scale (mRS) score 3-6 at 3 months after PCIS. Multivariable logistic regression analysis was used to identify predictors for poor outcome. The prognostic score, namely PCIS Outcome Score (PCISOS), was developed by assigning points to variables based on their relative β-coefficients in the logistic model.

RESULTS

The PCISOS was derived from 3,294 patients (median age 62 [interquartile range (IQR) 55-70] years; 2,250 [68.3%] men) and validated in 501 patients (median age 61 [IQR 53-68] years; 404 [80.6%] men). Among them, 384 (11.7%) and 64 (12.8%) had poor outcome 3 months after stroke in respective cohorts. Age, mRS before admission, NIH Stroke Scale on admission, ischemic stroke history, infarction distribution, basilar artery, and posterior cerebral artery stenosis or occlusion were identified as independent predictors for poor outcome and included in PCISOS. This easy-to-use integer scoring system identified a marked risk gradient between 4 risk groups. PCISOS performed better than previous scores, with an excellent discrimination (C statistic) of 0.80 (95% CI 0.77-0.83) in the derivation cohort and 0.81 (95% CI 0.77-0.84) in the validation cohort. Calibration test showed high agreement between the predicted and observed outcomes in both cohorts.

DISCUSSION

PCISOS can be applied for patients with PCIS with acute infarctions to predict functional outcome at 3 months post-PCIS. This simple tool helps clinicians to identify patients with PCIS with higher risk of poor outcome and provides reliable outcome expectations for patients. This information might be used for personalized rehabilitation plan and patient selection for future clinical trials to reduce disability and mortality.

Endovascular therapy for posterior cerebral artery occlusion: systematic review with meta-analysis

Endovascular therapy (EVT) is a highly effective stroke treatment, but trials validating this intervention did not include patients with posterior cerebral artery (PCA) occlusion. The aim of this systematic review with meta-analysis was to assess the efficacy and safety of EVT for acute PCA occlusion. PubMed, Scopus, ISI, and CENTRAL were searched for studies assessing EVT in adult patients with PCA occlusion. Outcomes of interest were recanalization, symptomatic intracerebral haemorrhage (sICH), mortality, functional independence, and excellent functional outcome at 90 days. Frequencies and odds ratios (ORs) were pooled using random effect models and heterogeneity was measured using the I2 statistic and explored by means of meta-regression. Fifteen studies were included, all observational. Recanalization rates were high [81%, 95% CI (73-88%)] and sICH rates low [2%, 95% CI (1-4%)]. Heterogeneity was high for recanalization (I2 = 80%) but not for sICH, and not accounted for by any of the moderators tested. Compared to best medical treatment, EVT was associated with higher chances of sICH [OR = 2.04, 95% CI (1.12-3.71)] and no effect in functional independence [OR = 0.98, 95% CI (0.63-1.54)], with a tendency to higher chances of excellent functional outcome [OR = 1.29, 95% CI (0.90-1.86)] and mortality [OR = 1.56, 95% CI (0.84-2.90)]. EVT for acute PCA occlusion is technically feasible but associated with higher chance of sICH. There is no evidence to support this treatment to achieve higher rates of functional independence, but other gains that can impact patients' quality of life cannot be excluded. More studies are required with robust design, better patient selection, and comprehensive outcome evaluation.

Endovascular Versus Medical Management in Distal Medium Vessel Occlusion Stroke: The DUSK Study

BACKGROUND

Endovascular treatment (EVT) is part of the usual care for proximal vessel occlusion strokes. However, the safety and effectiveness of EVT for distal medium vessel occlusions remain unclear. We sought to compare the clinical outcomes of EVT to medical management (MM) for isolated distal medium vessel occlusions.

METHODS

This is a retrospective analysis of prospectively collected data from seven comprehensive stroke centers. Patients were included if they had isolated distal medium vessel occlusion strokes due to middle cerebral artery M3/M4, anterior cerebral artery A2/A3, or posterior cerebral artery P1/P2 segments. Patients treated with EVT or MM were compared with multivariable logistic regression and inverse probability of treatment weighting. The primary outcome was the shift in the degree of disability as measured by the modified Rankin Scale (mRS) at 90 days. Secondary outcomes included 90-day good (mRS score, 0-2) and excellent (mRS score, 0-1) outcomes. Safety measures included symptomatic intracranial hemorrhage and 90-day mortality.

RESULTS

A total of 321 patients were included in the analysis (EVT, 179; MM, 142; 40.8% treated with intravenous thrombolysis). In the inverse probability of treatment weighting model, there were no significant differences between EVT and MM in terms of the overall degree of disability (mRS ordinal shift; adjusted odds ratio [aOR], 1.25 [95% CI, 0.95-1.64]; P=0.110), rates of good (mRS score, 0-2; aOR, 1.32 [95% CI, 0.97-1.80]; P=0.075) and excellent (aOR, 1.32 [95% CI, 0.94-1.85]; P=0.098) outcomes, or mortality (aOR, 1.20 [95% CI, 0.78-1.85]; P=0.395) at 90 days. The multivariable regression model showed similar findings. Moreover, there was no difference between EVT and MM in rates of symptomatic intracranial hemorrhage in the multivariable regression model (aOR, 0.57 [95% CI, 0.21-1.58]; P=0.277), but the inverse probability of treatment weighting model showed a lower likelihood of symptomatic intracranial hemorrhage (aOR, 0.46 [95% CI, 0.24-0.85]; P=0.013) in the EVT group.

CONCLUSIONS

This multicenter study failed to demonstrate any significant outcome differences among patients with isolated distal medium vessel occlusions treated with EVT versus MM. These findings reinforce clinical equipoise. Randomized clinical trials are ongoing and will provide more definite evidence.

Anesthesia modality in endovascular treatment for distal medium vessel occlusion stroke: intention-to-treat propensity score-matched analysis

BACKGROUND

The optimal anesthesia modality during endovascular treatment (EVT) for distal medium vessel occlusion (DMVO) stroke is uncertain. We aimed to evaluate the association of the anesthesia modality with procedural and clinical outcomes following EVT for DMVO stroke.

METHODS

This is a multicenter retrospective analysis of a prospectively collected database. Patients were included if they had DMVO involving the middle cerebral artery-M3/4, anterior cerebral artery-A2/3, or posterior cerebral artery-P1/P2-3, and underwent EVT. The cohort was divided into two groups, general anesthesia (GA) and non-general anesthesia (non-GA), and compared based on the intention-to-treat principle as primary analysis. We used propensity scores to balance the two groups. The primary outcome was the shift in the degree of disability as measured by the 90-day modified Rankin Scale (mRS). Secondary outcomes included successful reperfusion, as well as excellent (mRS 0-1) and good (mRS 0-2) clinical outcomes at 90 days. Safety measures included procedural complications, symptomatic intracerebral hemorrhage (sICH), and 90-day mortality.

RESULTS

Among 366 DMVO thrombectomies, 61 matched pairs were eligible for analysis. Median age and National Institutes of Health Stroke Scale score as well as other baseline demographic and clinical characteristics were balanced between both groups. The GA group had no difference in the overall degree of disability (common OR 1.19, 95% CI 0.52 to 2.86, P=0.67) compared with the non-GA arm. Likewise, the GA group had comparable rates of successful reperfusion (OR 2.38, 95% CI 0.80 to 7.07, P=0.12), good/excellent clinical outcomes (OR 1.14, 95% CI 0.44 to 2.96, P=0.79/(OR 0.65, 95% CI 0.24 to 1.81, P=0.41), procedural complications (OR 1.00, 95% CI 0.19 to 5.16, P>0.99), sICH (OR 3.24, 95% CI 0.83 to 12.68, P=0.09), and 90-day mortality (OR 1.43, 95% CI 0.48 to 4.27, P=0.52) compared with the non-GA group.

CONCLUSIONS

In patients with DMVO, our study showed that GA and non-GA groups had similar procedural and clinical outcomes, as well as safety measures. Further larger controlled studies are warranted.

Endovascular thrombectomy versus intravenous thrombolysis for primary distal, medium vessel occlusion in acute ischemic stroke

Introduction

In the absence of clinical trials, the benefit of endovascular therapy (EVT) on the treatment of acute ischemic stroke (AIS) with primary distal and medium vessel occlusions (DMVO) is still not well defined. The aim of the study is to evaluate EVT with or without intravenous thrombolysis (EVT ± IVT) in primary DMVO stroke in comparison with a control cohort treated with IVT alone.

Methods

We analysed all consecutive AIS with proven primary DMVO. Primary endpoints were excellent outcome, functional independence at 3 months follow-up, and early neurologic improvement at 1 day after treatment.

Results

One hundred and fourteen patients with DMVO strokes were included between 2019 and 2023. Propensity-weighted analysis showed no significant differences in EVT ± IVT vs IVT for the excellent outcome (adjusted OR [aOR], 1.575; 95% CI, 0.706-3.513), functional independence (aOR, 2.024; 95% CI, 0.845-4.848), early neurological improvement (aOR, 2.218; 95% CI, 0.937-5.247), mortality (aOR, 0.498; 95% CI, 0.177-1.406), symptomatic intracranial haemorrhage (aOR, 0.493; 95% CI, 0.102-2.385), and subarachnoid haemorrhage (aOR, 0.560; 95% CI, 0.143-2.187). The type of revascularization did not influence the percentage of cerebral volume lost (adjusted linear regression estimate, -19.171, t value, 11.562; p = 0.104).

Conclusions

This study supports the hypothesis that patients with primary DMVO stroke treated with EVT (±IVT) or IVT alone have comparable outcomes.

Thrombectomy vs Medical Management for Posterior Cerebral Artery Stroke: Systematic Review, Meta-Analysis, and Real-World Data

BACKGROUND AND OBJECTIVES

There is a paucity of high-level evidence for endovascular thrombectomy (EVT) in posterior cerebral artery (PCA) strokes.

METHODS

The MEDLINE, Embase, and Web of Science databases were queried for well-conducted cohort studies comparing EVT vs medical management (MM) for PCA strokes. Outcomes of interest included 90-day functional outcomes, symptomatic intracranial hemorrhage (sICH), and death. The level of evidence was determined per the Oxford Centre for Evidence-Based Medicine criteria. We also conducted a propensity score matched (PSM) analysis of the 2016-2020 National Inpatient Sample (NIS) to provide support for our findings with real-world data.

RESULTS

A total of 2,095 patients (685 EVT and 1,410 MM) were identified across 5 well-conducted cohort studies. EVT was significantly associated with higher odds of no disability at 90 days (odds ratio [OR] 1.25, 95% CI 1.04-1.50, p = 0.015) but not functional independence (OR 0.87, 95% CI 0.72-1.07, p = 0.18). EVT was also associated with higher odds of sICH (OR 2.48, 95% CI 1.55-3.97, p < 0.001) and numerically higher odds of death (OR 1.32, 95% CI 0.73-2.38; p = 0.35). PSM analysis of 95,585 PCA stroke patients in the NIS showed that EVT (n = 1,540) was associated with lower rates of good discharge outcomes (24.4% vs 30.7%, p = 0.037), higher rates of in-hospital mortality (8.8% vs 4.9%, p = 0.021), higher rates of ICH (18.2% and 11.7%, p = 0.008), and higher rates of subarachnoid hemorrhage (3.9% vs 0.6%, p < 0.001). Among patients with moderate to severe strokes (NIH Stroke Scale 5 or greater), EVT was associated with significantly higher rates of good outcomes (21.7% vs 13.8%, p = 0.023) with similar rates of mortality (7.6% vs 6.6%, p = 0.67) and ICH (17.8% vs, 13.1%, p = 0.18).

DISCUSSION

Our meta-analysis revealed that while EVT may be effective in alleviating disabling deficits due to PCA strokes, it is not associated with different odds of functional independence and may be associated with higher odds of sICH. These findings were corroborated by our large propensity score matched analysis of real-world data in the United States. Thus, the decision to pursue PCA thrombectomies should be carefully individualized for each patient. Future randomized trials are needed to further explore the efficacy and safety of EVT for the treatment of PCA strokes.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that in patients with acute PCA ischemic stroke, treatment with EVT compared with MM alone was associated with higher odds of no disabling deficit at 90 days and higher odds of sICH.

Endovascular thrombectomy for treatment of isolated posterior cerebral artery occlusion: a real-world analysis of hospitalizations in the United States

BACKGROUND

Despite renewed interest and recently demonstrated efficacy for endovascular thrombectomy (EVT) for treatment of acute ischemic stroke (AIS) of the posterior circulation, to date, no randomized clinical trials have been conducted to evaluate EVT for isolated occlusions of the posterior cerebral artery (IPCA).

METHODS

Hospitalizations for adult patients with primary admission diagnoses of IPCA occlusion were identified in the National Inpatient Sample registry during the period of 2016-2020. The study exposure was treatment with EVT, and primary clinical endpoints included favorable functional outcome (defined as discharge disposition to home without services, previously shown to have high concordance with modified Rankin scale scores 0-2), in-hospital mortality, and any intracranial hemorrhage (ICH). Inverse probability of treatment weighting (IPTW) was performed to balance baseline clinical characteristics between those receiving EVT or medical management (MM).

RESULTS

This analysis identified 34,880 IPCA occlusion hospitalizations, 730 (2.1%) of which documented treatment with EVT. Following IPTW adjustment, EVT was associated with favorable outcome in IPCA patients presenting with mild deficits (M-D) (NIHSS < 6) [adjusted odds ratio (aOR) 2.36, 95% confidence interval (CI) 2.27, 2.45; p < 0.001] and in those presenting with moderate-to-severe deficits (M-S-D) (NIHSS 6-42) (aOR 2.00, 95% CI 1.86, 2.15; p < 0.001). Mortality rates did not differ among those with M-S-D [EVT 4.8% vs. MM 4.7%, p = 0.742], while ICH rates were lower.

CONCLUSION

Retrospective analysis of a large administrative registry in the Unites States demonstrates an association of EVT with favorable outcomes following IPCA occlusion, without concomitant risk of hemorrhagic transformation or mortality.

Successful Thrombectomy of the Posterior Cerebral Artery P2 Segment in a 61-Year-Old Man with Acute Ischaemic Stroke: A Case Report

BACKGROUND Acute ischemic stroke in the posterior cerebral artery (PCA) territory can lead to persistent disabling deficits. The PCA is divided into 4 segments. The P2 segment begins at the posterior communicating artery and curves around the midbrain and above the tentorium cerebelli. This report is of a 61-year-old man with acute ischemic stroke involving the left hippocampus treated with direct thrombectomy of the P2 segment of the PCA. CASE REPORT A 61-year-old white man presented with transient amnesia, aphasia, right-sided hemianopia, dizziness, and persistent acute memory deficits. Magnetic resonance imaging (MRI) showed a left hippocampal acute ischemic stroke with left PCA occlusion in the P2 segment. Despite a low National Institutes of Health Stroke Scale (NIHSS) score and the already-formed lesion in the hippocampus, successful stent retriever thrombectomy was performed due to a considerable perfusion-diffusion mismatch and a persistent potentially disabling neurocognitive deficit. Due to partial thrombus dislocation, occlusion of the common origin of the right posterior inferior cerebellar artery (PICA) and anterior inferior cerebellar artery (AICA) occurred and was immediately treated by thrombectomy to prevent severe cerebellar infarction. His clinical symptoms completely resolved and a neuropsychological exam showed no residual deficits. CONCLUSIONS Thrombectomy of the P2 segment of the PCA is feasible and can be considered to treat patients with acute occlusion at risk for persistent disabling deficits, based on clinical estimation of the impact of such deficits and the presence of potentially salvageable brain tissue. Potential procedural complications should be sought out and immediately treated, if technically feasible.

First pass effect as an independent predictor of functional outcomes in medium vessel occlusions: An analysis of an international multicenter study

INTRODUCTION

First pass effect (FPE), achievement of complete recanalization (mTICI 2c/3) with a single pass, is a significant predictor of favorable outcomes for endovascular treatment (EVT) in large vessel occlusion stroke (LVO). However, data concerning the impact on functional outcomes and predictors of FPE in medium vessel occlusions (MeVO) are scarce.

PATIENTS AND METHODS

We conducted an international retrospective study on MeVO cases. Multivariable logistic modeling was used to establish independent predictors of FPE. Clinical and safety outcomes were compared between the two study groups (FPE vs non-FPE) using logistic regression models. Good outcome was defined as modified Rankin Scale 0-2 at 3 months.

RESULTS

Eight hundred thirty-six patients with a final mTICI ⩾ 2b were included in this analysis. FPE was observed in 302 patients (36.1%). In multivariable analysis, hypertension (aOR 1.55, 95% CI 1.10-2.20) and lower baseline NIHSS score (aOR 0.95, 95% CI 0.93-0.97) were independently associated with an FPE. Good outcomes were more common in the FPE versus non-FPE group (72.8% vs 52.8%), and FPE was independently associated with favorable outcome (aOR 2.20, 95% CI 1.59-3.05). 90-day mortality and intracranial hemorrhage (ICH) were significantly lower in the FPE group, 0.43 (95% CI, 0.25-0.72) and 0.55 (95% CI, 0.39-0.77), respectively.

CONCLUSION

Over 2/3 of patients with MeVOs and FPE in our cohort had a favorable outcome at 90 days. FPE is independently associated with favorable outcomes, it may reduce the risk of any intracranial hemorrhage, and 3-month mortality.

Endovascular therapy versus best medical management for isolated posterior cerebral artery occlusion: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Isolated posterior cerebral artery occlusions (iPCAO) were underrepresented in pivotal randomized clinical trial (RCTs) of endovascular thrombectomy (EVT) in ischemic stroke, and the benefit of EVT in this population is still indeterminate. We performed a systematic review and a meta-analysis to compare the safety and efficacy of EVT compared to best medical management (BMM) in patients with iPCAO.

METHODS

We searched Medline/PubMed, Embase, Web of Science, and the Cochrane databases up to May 2023 for eligible studies reporting outcomes of patients with iPCAO treated with EVT or BMM. We pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI) using a random-effects model.

RESULTS

Seven studies involving 2560 patients were included. EVT was associated with significantly higher likelihood of early neurological improvement (OR, 2.31 [95% CI, 1.38-2.91]; p < 0.00001) and visual field normalization (OR, 3.08 [95% CI, 1.76-5.38]; p < 0.0001) compared to BMM. Rates of good functional outcomes (mRS 0-2) were comparable between the two arms (OR, 0.88 [95% CI, 0.70-1.10]; p = 0.26). Symptomatic intracranial hemorrhage (sICH) was comparable between the two groups (OR, 1.94 [95% CI, 0.96-3.93]; p = 0.07). Mortality was also similar between the two groups (OR, 1.36; [95% CI, 0.77-2.42]; p = 0.29).

CONCLUSIONS

In patients with iPCAO, EVT was associated with visual and early neurological improvement but with a strong trend toward increased sICH. Survival and functional outcomes may be slightly poorer. The role of EVT in iPCAO remains uncertain.

Effect of anesthetic strategies on distal stroke thrombectomy in the anterior and posterior cerebral artery

BACKGROUND

Numerous questions regarding procedural details of distal stroke thrombectomy remain unanswered. This study assesses the effect of anesthetic strategies on procedural, clinical and safety outcomes following thrombectomy for distal medium vessel occlusions (DMVOs).

METHODS

Patients with isolated DMVO stroke from the TOPMOST registry were analyzed with regard to anesthetic strategies (ie, conscious sedation (CS), local (LA) or general anesthesia (GA)). Occlusions were in the P2/P3 or A2-A4 segments of the posterior and anterior cerebral arteries (PCA and ACA), respectively. The primary endpoint was the rate of complete reperfusion (modified Thrombolysis in Cerebral Infarction score 3) and the secondary endpoint was the rate of modified Rankin Scale score 0-1. Safety endpoints were the occurrence of symptomatic intracranial hemorrhage and mortality.

RESULTS

Overall, 233 patients were included. The median age was 75 years (range 64-82), 50.6% (n=118) were female, and the baseline National Institutes of Health Stroke Scale score was 8 (IQR 4-12). DMVOs were in the PCA in 59.7% (n=139) and in the ACA in 40.3% (n=94). Thrombectomy was performed under LA±CS (51.1%, n=119) and GA (48.9%, n=114). Complete reperfusion was reached in 73.9% (n=88) and 71.9% (n=82) in the LA±CS and GA groups, respectively (P=0.729). In subgroup analysis, thrombectomy for ACA DMVO favored GA over LA±CS (aOR 3.07, 95% CI 1.24 to 7.57, P=0.015). Rates of secondary and safety outcomes were similar in the LA±CS and GA groups.

CONCLUSION

LA±CS compared with GA resulted in similar reperfusion rates after thrombectomy for DMVO stroke of the ACA and PCA. GA may facilitate achieving complete reperfusion in DMVO stroke of the ACA. Safety and functional long-term outcomes were comparable in both groups.

Revascularization of arterial occlusions in posterior circulation acute ischemic stroke

PURPOSE OF REVIEW

This review highlights the latest advancements achieved in the revascularization of arterial occlusions associated with an acute ischemic stroke affecting the posterior circulation. It delves into the frequency and outcomes based on specific arterial segments and presents current evidence supporting revascularization treatments, including intravenous thrombolysis and endovascular thrombectomy.

RECENT FINDINGS

Comprehensive evidence for treatment across major arterial segments of the posterior circulation -- vertebral artery, basilar artery, posterior cerebral artery, cerebellar arteries, and multilevel posterior occlusions -- is provided. Additionally, the latest findings from randomized clinical trials on basilar artery occlusion are explored alongside results from extensive retrospective analyses of isolated vertebral and posterior cerebral artery occlusions.

SUMMARY

Current research supports the treatment decision in acute ischemic strokes of the posterior circulation using both intravenous thrombolysis and endovascular thrombectomy. This review also emphasizes existing knowledge gaps in the management of these strokes and advocates for more randomized clinical trials, notably concerning the posterior cerebral artery (currently ongoing), isolated vertebral artery, and multilevel posterior circulation occlusions.

Endovascular thrombectomy for posterior cerebral artery strokes in the national inpatient sample (EaT PeCANpIeS) study

BACKGROUND

Posterior cerebral arteries with acute ischemic strokes (PCA-AISs) comprise around 2% of all acute ischemic strokes and may result in significant long-term deficits. Current guidance regarding endovascular thrombectomy (EVT) for PCA-AIS is insufficient as no published randomized trials exist.

METHODS

An analysis of the National Inpatient Sample database compared medical management versus EVT for PCA-AIS. Propensity score matching was applied to adjust for nonrandomization.

RESULTS

The study included 19,655 patients. Before matching, the EVT cohort had significantly higher National Institutes of Health Stroke Scale (NIHSS) (10.21 vs. 4.67, p < 0.001), had lower rates of favorable functional outcomes, functional independence, and higher rates of intracranial hemorrhage (ICH) and inpatient mortality. After matching, no differences in functional outcomes were identified, but revealed a higher proportion of ICH in the EVT group (17.45% vs. 8.98%, p < 0.001). However, NIHSS subgroup analysis identified improved functional outcomes associated with the EVT group who presented with an NIHSS between 10 and 19 both in terms of rates of favorable functional outcomes (35.56% vs. 12.09%, p < 0.001) and rates of functional independence (26.67% vs. 9.34%, p < 0.01). On further investigation, the clinical benefit, in the NIHSS 10-19 subgroup, was driven by patients receiving EVT in combination with intravenous thrombolysis (IVT).

CONCLUSIONS

This analysis shows that current national practices utilize EVT for more severe PCA strokes. Clinical benefit was only detected in patients with moderate stroke severity (NIHSS 10-19) who were treated with combined EVT and IVT. Further work is needed to investigate the features of PCA-AIS that might benefit from EVT the most.

Cineangiography versus standard digital subtraction angiography in mechanical thrombectomy: lowering the radiation exposure without sacrificing the outcome

BACKGROUND

Endovascular thrombectomy has become a standard procedure for the treatment of acute ischemic stroke caused by large vessel occlusion. Radiation exposure to the patient and operators during mechanical thrombectomy procedures is a concern.

METHODS

The use of a high frames per second unmasked protocol-cineangiography (CINE)-derived from cardiac intervention could mitigate radiation exposure without sacrificing procedural and clinical outcomes.

RESULTS

The analysis of a prospective-maintained monocentric database of 131 patients who underwent mechanical thrombectomy (65 with the CINE protocol and 66 with the conventional digital subtraction angiography (DSA) protocol) showed a significant reduction in radiation exposure for both air kerma (AK) and dose-area product (DAP) indicators (AK 463.7 mGy vs 772 mGy, P<0.01; DAP 41.35 Gy/cm2 CINE vs 83.77 Gy/cm2 DSA, P<0.01), with no differences regarding both safety and efficacy outcomes (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b 78.4% CINE and 81.5% DSA, P=0.79; overall complications rate both intracranial and extracranial 23% CINE and 19.6% DSA, P=0.65). There were no significant differences in post-thrombectomy radiographic hemorrhagic conversion rate (P=0.77) or functional independence on discharge defined as modified Rankin Scale score ≤2 (P=0.39). A post-hoc image assessment of vessel point occlusion and recanalization mTICI score performed by three experienced interventional neuroradiologists not involved in the procedure showed a non-significant difference between the two groups regarding occlusion point (0.928 vs 0.953, P=0.31) and recanalization grade (0.814 vs 0.847, P=0.62).

CONCLUSIONS

Our initial experience demonstrated that reduction of the quality of CINE images caused no modifications in safety and efficacy and should fit within the context of diagnostic requests in an intracranial revascularization procedure.

Common design and data elements reported in active mechanical thrombectomy trials focusing on distal medium vessel occlusions and minor strokes: a systematic review

BACKGROUND

Distal medium vessel occlusions (DMVOs) and minor strokes represent emerging frontiers in mechanical thrombectomy (MT). Although several randomized clinical trials (RCTs) are underway, the design characteristics of these trials and the specific questions they aim to address have not been extensively explored. This current study sought to investigate the design and data elements reported in active prospective DMVO and minor stroke studies.

METHODS

The ClinicalTrials.gov database was searched for ongoing prospective studies assessing the role of MT in patients with DMVOs or minor strokes. The Nested Knowledge AutoLit platform was utilized to categorize reported outcomes and inclusion/exclusion criteria. Frequencies of reported data elements were extracted from study protocols.

RESULTS

A total of 10 (8 DMVO and 2 minor stroke) studies enrolling 3520 patients were included. All DMVO studies employ different criteria regarding target occlusion locations. Five DMVO studies use stent retrievers as the first-line thrombectomy technique (62.5%, 5/8), while three studies allow any MT techniques, generally at the operator's discretion. Four DMVO studies permit intravenous thrombolysis (IVT) utilization in both intervention and control arms (50%, 4/8). The DISTALS trial excludes patients receiving IVT, while the DUSK trial and Tigertriever registry only enroll patients who are ineligible for IVT or for whom IVT failed to achieve reperfusion. DMVO studies exhibit notable heterogeneity in symptom onset duration thresholds for inclusion (<6 hours: 2 studies; <12 hours: 2 studies; <24 hours: 3 studies). Minor stroke trials employ similar inclusion criteria and outcome measures except for symptom duration thresholds for inclusion (8 hours for ENDOLOW and 23 hours for MOSTE).

CONCLUSIONS

There is considerable heterogeneity among active DMVO trials regarding potential target DMVO locations and time thresholds for inclusion based on the last known well time. Furthermore, our review indicates that the utility of aspiration thrombectomy in DMVOs and the advantages of MT without IVT over IVT alone will remain largely unexplored even after completion of active DMVO trials.

Safety and efficacy of endovascular thrombectomy for primary and secondary MeVO

BACKGROUND

Medium-vessel occlusions (MeVO) are emerging as a new target for endovascular treatment (EVT). Primary MeVO occur de novo, while secondary MeVO arise from large vessel occlusion (LVO) through clot migration or fragmentation - spontaneously, following intravenous thrombolysis or EVT. We aimed to evaluate efficacy and safety of EVT in primary and EVT-induced secondary MeVO.

METHODS

Retrospective single-center study on consecutive EVT-treated acute ischemic stroke, from 2019-to-2021. We considered: (1) exclusive-LVO, patients with LVO and - in case of residual distal occlusion - no rescue endovascular procedure; (2) primary MeVO: initial A2, A3, M2 non-dominant, M3, P2, P3 occlusions; (3) EVT-induced secondary MeVO, presenting LVO with subsequent (treated) EVT-induced MeVO. We compared (univariable/multivariable logistic regression) EVT efficacy (eTICI≥2b, 3-month modified Rankin Scale [mRS] 0-2) and safety (EVT-complications [vessel dissection, perforation, persistent-SAH], symptomatic ICH) in all MeVO versus exclusive-LVO, primary MeVO versus exclusive-LVO, EVT-induced secondary MeVO versus exclusive-LVO and EVT-induced secondary MeVO versus primary MeVO.

RESULTS

We included 335 patients: 221 (66.0 %) exclusive-LVO and 114 (34.0 %) MeVO (55 [48.2 %] primary, 59 [51.8 %] secondary). Compared to exclusive-LVO, primary MeVO had higher rates of EVT complications (aOR 3.77 [95%CI 1.58-9.00],p=0.003), lower rates of eTICI≥2b (aOR 0.32 [95%CI 0.12-0.88],p=0.027) and mRS 0-2 (aOR 0.28 [95%CI 0.13-0.63],p=0.002). EVT-induced secondary MeVO had no major differences in efficacy and safety outcomes compared to exclusive-LVO, but a better mRS 0-2 (aOR 8.00 [95%CI 2.12-30.17],p=0.002) compared to primary MeVO.

CONCLUSIONS

Primary and EVT-induced secondary MeVO showed different safety/efficacy EVT-related profiles. Dedicated randomized data are needed to identify the best acute reperfusion strategy in the two categories.

Mechanical thrombectomy for the treatment of primary and secondary distal medium-vessel occlusion stroke: systematic review and meta-analysis

BACKGROUND

There is limited evidence on the indication and role of mechanical thrombectomy (MT) in patients with distal medium-vessel occlusions (DMVOs). The aim of this systematic review and meta-analysis was to evaluate all the evidence available on the efficacy and safety of MT techniques (stent retriever, aspiration) in primary and secondary DMVOs.

METHODS

Five databases were searched from inception to January 2023 for studies of MT in primary and secondary DMVOs. Outcomes of interest included favorable functional outcome (90-day modified Rankin scale (mRS) 0-2), successful reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2b-3), symptomatic intracerebral hemorrhage (sICH), and 90-day mortality. Prespecified subgroup meta-analyses according to the specific MT technique and to the vascular territory (distal M2-M5, A2-A5, P2-P5) were also performed.

RESULTS

A total of 29 studies with 1262 patients were included. For primary DMVOs (n=971 patients), pooled rates of successful reperfusion, favorable outcome, 90-day mortality and sICH were 84% (95% confidence interval (CI) 76 to 90%), 64% (95% CI 54 to 72%), 12% (95% CI 8 to 18%), and 6% (95% CI 4 to 10%), respectively. For secondary DMVOs (n=291 patients), pooled rates of successful reperfusion, favorable outcome, 90-day mortality and sICH were 82% (95% CI 73 to 88%), 54% (95% CI 39 to 69%), 11% (95% CI 5 to 20%), and 3% (95% CI 1 to 9%), respectively. Subgroup analyses by MT technique and by vascular territory showed no differences in primary and secondary DMVOs.

CONCLUSION

Our findings suggest that MT using aspiration or stent retriever techniques appears to be effective and safe in primary and secondary DMVOs. However, given the level of evidence of our results, further confirmation in well-designed randomized controlled trials is needed.

Endovascular therapy for acute ischemic stroke with distal medium vessel occlusion: a systematic review and meta-analysis

AIMS

Endovascular therapy (EVT) for distal medium vessel occlusions (DMVOs) is a potential frontier of acute ischemic stroke (AIS) treatment, but its efficacy against best medical therapy (BMT) remains unknown. We performed a systematic review and meta-analysis evaluating the efficacy and safety of EVT versus BMT in primary DMVO.

METHODS

We systematically searched PubMed, Cochrane Library and Embase, from inception to August 14, 2022, for studies comparing EVT with BMT in DMVO-AIS. We adopted the Distal Thrombectomy Summit Group's definition of DMVO. Efficacy outcomes were functional independence (90-day modified Rankin Scale (mRS) 0-2) and excellent functional outcomes (90-day mRS 0-1). Safety outcomes were symptomatic intracranial hemorrhage (sICH) and 90-day mortality.

RESULTS

Fourteen observational and two randomized-controlled studies were included, with 1202 patients receiving EVT and 1267 receiving BMT. After trim-and-fill correction, EVT achieved significantly better odds of functional independence than BMT (adjusted OR 1.61, 95% CI 1.06 to 2.43). There were no significant differences in overall excellent functional outcomes (OR 1.23, 95% CI 0.88 to 1.71), sICH (OR 1.44, 95% CI 0.78 to 2.66), and mortality (OR 1.03, 95% CI 0.73 to 1.45). Stratified by EVT method, mechanical thrombectomy±intra-arterial thrombolysis achieved more excellent functional outcomes than BMT (OR 1.59, 95% CI 1.13 to 2.23). In mild strokes (National Institutes of Health Stroke Scale score <6), EVT caused significantly more sICH (OR 6.30, 95% CI 1.55 to 25.64).

CONCLUSIONS

EVT shows promising efficacy benefit over BMT for primary DMVO-AIS. Further randomized controlled trials are necessary to evaluate the efficacy and safety of EVT in DMVO-AIS.

Endovascular therapy versus medical management for mild strokes due to medium and distal vessel occlusions

BACKGROUND

Distal and medium vessel occlusion (DMVO) strokes account for up to 40% of all acute ischemic strokes, many of which have a low initial deficit severity. Increasingly, endovascular treatment (EVT) is considered for these patients. However, there is a paucity of data comparing potential safety and efficacy of EVT versus best medical management (BMT) in these patients, particularly when presenting with mild symptoms.

METHODS

We retrospectively analyzed consecutive DMVO patients with NIHSS ≤6 who presented between January 2018 and December 2021 within 24 h from last seen well. We compared early and late clinical outcomes, as well as safety outcomes using multivariable linear and logistic regression analyses to determine whether EVT was independently associated with the outcomes of interest.

RESULTS

We included 80 subjects that fulfilled our study criteria (n = 41 BMT and n = 39 EVT). On adjusted analyses, when comparing EVT and BMT groups, there was no statistical difference in the NIHSS at discharge (Coefficient = -0.6, 95%-CI = -3.45-2.26, p = 0.678) or in the modified Rankin scale (mRS) at discharge (Coefficient = 0.37, 95%-CI = -0.52-1.25, p = 0.408). Furthermore, there was no difference in the 3-month mRS defined as good (mRS 0-2) (OR = 0.56, 95%-CI = 0.17-1.83, p = 0.341) or excellent (mRS 0-1) (OR = 0.45, 95%-CI = 0.15-1.34, p = 0.152). Finally, there was no difference in the incidence of all-type parenchymal hemorrhage (OR = 0.9, 95%-CI = 0.22-3.62, p = 0.879).

CONCLUSIONS

We found that among DMVO patients with low admission NIHSS treatment with EVT versus BMT was associated with similar outcomes. Larger prospective studies are required to confirm these findings.

Epidemiology, organization, diagnosis and treatment of acute ischemic stroke

The management of acute ischemic stroke is changing. Over the period of 2010-2050, the number of incident strokes is expected to be more than double. Rapid access to mechanical thrombectomy for patients with large vessel occlusion is critically associated with their functional outcome. Moreover, patients with first pass effect had a better clinical outcome, lower mortality, and fewer procedural adverse events. We discuss some advances in acute ischemic stroke regarding the organization, the diagnosis and the treatment.

Current and future trends in acute ischemic stroke treatment: direct-to-angiography suite, middle vessel occlusion, large core, and minor strokes

Since the publication of the landmark thrombectomy trials in 2015, the field of endovascular therapy for ischemic stroke has been rapidly growing. The very low number needed to treat to provide functional benefits shown by the initial randomized trials has led clinicians and investigators to seek to translate the benefits of endovascular therapy to other patient subgroups. Even if the treatment effect is diminished, currently available data has provided sufficient information to extend endovascular therapy to large infarct core patients. Recently, published data have also shown that sophisticated imaging is not necessary for late time- window patients. As a result, further research into patient selection and the stroke pathway now focuses on dramatically reducing door-to-groin times and improving outcomes by circumventing classical imaging paradigms altogether and employing a direct-to-angio suite approach for selected large vessel occlusion patients in the early time window. While the results of this approach mainly concern patients with severe deficits, there are further struggles to provide evidence of the efficacy and safety of endovascular treatment in minor stroke and large vessel occlusion, as well as in patients with middle vessel occlusions. The current lack of good quality data regarding these patients provides significant challenges for accurately selecting potential candidates for endovascular treatment. However, current and future randomized trials will probably elucidate the efficacy of endovascular treatment in these patient populations.

Pearls for the Emergency Clinician: Posterior Circulation Stroke

BACKGROUND

Posterior circulation (PC) stroke in adults is a rare, frequently misdiagnosed, serious condition that carries a high rate of morbidity.

OBJECTIVE OF THE REVIEW

This review evaluates the presentation, diagnosis, and management of PC stroke in the emergency department (ED) based on current evidence.

DISCUSSION

PC stroke presents most commonly with dizziness or vertigo and must be distinguished from more benign diagnoses. Emergency clinicians should consider this condition in patients with dizziness, even in younger patients and those who do not have traditional stroke risk factors. Neurologic examination for focal neurologic deficit, dysmetria, dysarthria, ataxia, and truncal ataxia is essential, as is the differentiation of acute vestibular syndrome vs. spontaneous episodic vestibular syndrome vs. triggered episodic vestibular syndrome. The HINTS (head impulse, nystagmus, and test of skew) examination can be useful for identifying dizziness presentations concerning for stroke when performed by those with appropriate training. However, it should only be used in patients with continuous dizziness who have ongoing nystagmus. Contrast tomography (CT), CT angiography, and CT perfusion have limited sensitivity for identifying PC strokes, and although magnetic resonance imaging is the gold standard, it may miss some PC strokes early in their course. Thrombolysis is recommended in patients presenting within the appropriate time window for thrombolytic therapy, and although some data suggest endovascular therapy for basilar artery and posterior cerebral artery infarcts is beneficial, its applicability for all PC strokes remains to be determined.

CONCLUSIONS

An understanding of PC stroke can assist emergency clinicians in diagnosing and managing this disease.

(VISIION-S): Viz.ai Implementation of Stroke augmented Intelligence and communications platform to improve Indicators and Outcomes for a comprehensive stroke center and Network - Sustainability

OBJECTIVES

As Comprehensive Stroke Centers (CSCs) strive to improve neuro-intervention (NIR) times, process improvements are put in place to streamline workflows. Our prior publication (VISIION) demonstrated improvements in key performance indicators (KPIs). The purpose VISIION-S was to analyze whether those results were sustainable.

MATERIALS AND METHODS

Consecutive Direct Arriving LVO (DALVO) and telemedicine transfer LVO (BEMI) stroke NIR cases were assessed, including subgroups of DALVO-OnHours, DALVO-OffHours, BEMI-OnHours, and BEMI-OffHours. We analyzed times for the original 6 months pre (6/10/20-1/15/21) and compared them to a 17 month post-implementation period (1/16/21- 6/25/22) to evaluate for sustainability. Mann-Whitney U was utilized.

RESULTS

150 NIR cases were analyzed pre (n = 47) v. post (n = 103) implementation (DALVO-OnHours 7 v. 20, DALVO-OffHours 10 v. 25, BEMI-OnHours 13 v. 20, BEMI-OffHours 17 v. 38). For Door-to-groin (DTG), improvement was noted for DALVO-OffHours 39%(157 min,96 min;p < 0.001), DALVO-ALL 25%(127 min,95 min;p = 0.006), BEMI-OffHours 46%(45 min,25 min;p = 0.023), and BEMI-ALL 40%(42 min,25 min;p = 0.005). Activation-to-groin (ATG), door-to-device (DTD), and door-to-recanalization (DTR) also showed statistical improvements. For DALVO-OffHours, there were reductions in door to CT (DTC) 80%(26 min,5 min;p < 0.001), ATG 32%(90 min,61 min;p = 0.036), DTG 39%(157 min,96 min;p < 0.001), DTD 31%(178 min,123 min;p = 0.002), and DTR 32%(197 min,135 min;p = 0.003).

CONCLUSIONS

We noted sustainability over a 17 month period with sustained reduction in KPIs for even more NIR time interval comparisons. In the greatest opportunity subgroup (DALVO-OffHours), we noted a reduction in all 5 time interval metrics. Our sustainability finding is important to show that process improvements continued even after the immediate period, adding credibility to the results. Models such as this could be useful for other centers striving to optimize workflow and improve times.