Clinical outcomes of first-pass effect after mechanical thrombectomy for acute ischemic stroke: A systematic review and meta-analysis

Long-term functional outcomes for elderly patients treated with endovascular thrombectomy

BackgroundFunctional outcomes in elderly thrombectomy patients have been commonly reported up to 90 days, though long-term neurological status is not as well characterized. We studied 1-year outcomes in patients ≥ 80 years old and identified predictors of functional independence in elderly patients.MethodsRetrospective analysis of anterior circulation thrombectomy patients presenting from November 2016-August 2023 to a large health system. The primary outcome was 1-year modified Rankin Scale score (mRS) 0-2. Outcomes were compared between patients ≥ 80 and < 80 years old. Logistic regression was performed to identify predictors of 1-year functional independence in the elderly.Results957 patients were included, 220 (23%) of whom were ≥ 80 years old. A significantly lower proportion of patients ≥ 80 years old, compared to < 80 years, were functionally independent at 1-year (18.6% versus 45.9%, p < 0.001). In the elderly, predictors of functional independence included age (odds ratio (OR) 0.83, 95% confidence interval (CI) 0.74-0.93, p = 0.002), premorbid mRS score (OR 0.51, 95% CI 0.29-0.88, p = 0.016), presenting National Institutes of Health Stroke Scale score (OR 0.93, 95% CI 0.87-0.995, p = 0.035), cerebral blood volume index (OR 50.7, 95% CI 2.8-935, p = 0.008), and first-pass recanalization (OR 2.77, 95% CI 1.20-6.38, p = 0.017).ConclusionElderly thrombectomy patients had lower rates of functional independence at 1-year, though these are similar to previously reported rates at 90-days in octogenarians and nonagenarians. Factors associated with good outcomes in the elderly, including collateral status and single-pass revascularization, may be prognostically informative beyond the 90-day time window.

Endovascular recanalization of symptomatic chronic cerebral artery occlusion: predictors for successful recanalization and perioperative complications

Background and purpose

Endovascular recanalization and stenting has been used to treat patients with symptomatic chronic cerebral artery occlusion, including intracranial vertebrobasilar artery occlusion and internal carotid artery occlusion. Our challenge is to improve success rates and reduce the incidence of postoperative complications. This study sought to identify potential predictors for successful recanalization.

Methods

Our study included 103 consecutive patients between February 2021 and October 2024 with symptomatic chronic cerebral artery occlusion who were treated with endovascular recanalization. We recorded clinical information, laboratory and examination results, radiologic characteristics and procedural results of patients. Factors affecting surgical outcomes were analyzed by univariate and multivariate analyses.

Results

A total of 103 consecutive CCAO recanalization attempts were performed from February 2021 to October 2024 in 103 patients (78 men; age 61.1 ± 11.1 years; range: 32-81 years) with overall technical success rate 68.9%. Patients had chronic comorbidities such as hypertension (78, 75.7%), diabetes mellitus (32, 31.10%), and cardiac disease (12, 11.7%). 38 (36.9%) had a history of smoking, and 23 (22.3%) had a history of drinking. The rate of overall intraoperative complication was 10.7% (11/103). Multivariate analysis showed that stump morphology, smoking history, duration from last neurologic event (longer than 6 months or not), age, NLR were significantly associated with successful recanalization. According to the coefficients of the prediction model, the technical success rates were 100, 66.7 and 11.1% in patients with ≤6, 6-10, ≥10 points, respectively.

Conclusion

The morphology of occluded stumps, duration from last neurologic event, age, smoking history and NLR can be used to predict the outcome of vascular recanalization.

Tirofiban on First-Pass Recanalization in Acute Stroke Endovascular Thrombectomy: The OPTIMISTIC Randomized Clinical Trial

Importance

Tirofiban is a nonpeptide antagonist of the glycoprotein IIb/IIIa receptor that inhibits platelet aggregation selectively. Despite widespread use in acute ischemic stroke in conjunction with endovascular treatment, the role of tirofiban is uncertain.

Objective

To assess whether intravenous tirofiban initiated before endovascular thrombectomy improves thrombectomy outcomes by achieving first-pass recanalization without intracranial hemorrhagic risk.

Design, Setting, and Participants

This was a multicenter, prospective, open-label, blinded, end point phase 2 randomized clinical trial that enrolled patients from 7 Chinese hospital stroke centers between April 30, 2021, and July 16, 2023. Eligible patients were aged 18 to 85 years with large vessel occlusion (internal carotid artery or M1 or M2 segment of middle cerebral artery) and were considered for endovascular thrombectomy within 24 hours of ischemic stroke onset or last known well time. Patients with a history of atrial fibrillation or treated with intravenous thrombolysis were excluded.

Intervention

Patients were randomly assigned (1:1) to intravenous tirofiban (10 μg/kg bolus plus 0.1 μg/kg per minute infusion for 24 hours) or standard care before endovascular thrombectomy using a web-based, computer-generated randomization procedure.

Main Outcomes and Measures

The primary outcome was the proportion of patients achieving first-pass recanalization without symptomatic intracranial hemorrhage. First-pass recanalization was assessed by reviewers blinded to treatment allocation and predefined as successful recanalization of a targeted vessel after a single pass of thrombectomy. The primary outcome was analyzed by modified Poisson regression with robust error estimation, adjusting for time from onset or last known well time to randomization and vessel occlusion site.

Results

Among 200 patients randomized (median age, 66 years [IQR, 58-72 years]; 146 male [73%]), 102 were allocated to receive intravenous tirofiban, and 98 were allocated to receive standard care before endovascular thrombectomy. In the intention-to-treat analysis, 64 of 99 patients receiving tirofiban (65%) and 46 of 95 control patients (48%) achieved the primary outcome of first-pass recanalization without symptomatic intracranial hemorrhage (adjusted risk ratio, 1.34 [95% CI, 1.04-1.73]; P = .03). Incidence of symptomatic intracranial hemorrhage was 0% (0 of 101 patients) in the tirofiban group vs 6% (6 of 98 patients) in the control group (unadjusted risk difference, -0.06 [95% CI, -0.11 to -0.01]).

Conclusions and Relevance

In this randomized clinical trial of patients who had acute ischemic stroke with no history of atrial fibrillation and no prior intravenous thrombolysis, intravenous tirofiban administered before endovascular thrombectomy increased the likelihood of first-pass recanalization without symptomatic intracranial hemorrhage. These findings suggest that neurointerventionalists may consider this pre-procedure antiplatelet treatment to facilitate endovascular thrombectomy.

Trial Registration

ClinicalTrials.gov Identifier: NCT04851457.

First pass effect in patients with large core infarcts undergoing mechanical thrombectomy: subgroup analysis of the prospective international ASSIST registry

BACKGROUND

Studies have described a first pass effect (FPE) where patients with successful recanalization after one pass experience better outcomes. Few studies have evaluated this in patients with large core infarctions.

OBJECTIVE

To determine whether patients with large core infarcts undergoing mechanical thrombectomy in which first pass reperfusion is achieved experience improved outcomes compared with those who undergo more than one pass.

METHODS

The ASSIST Registry, a prospective, global, multicenter registry of patients with anterior circulation large vessel occlusion (LVO) undergoing mechanical thrombectomy was used. Adults with internal carotid artery/M1/M2 occlusions and preprocedural Alberta Stroke Program Early CT Score (ASPECTS) <6 were included. The variable of interest was number of thrombectomy passes (dichotomized to 1 or >1) performed for the target occlusion. The primary outcome was 90-day good functional outcome defined as modified Rankin Scale (mRS) score 0-3.

RESULTS

150 patients with a mean age of 66 years were included. Most patients had ASPECTS of 4 (33%) or 5 (59%). 77 patients (51%) underwent one pass. Compared with patients with one pass, those with more than one pass had significantly lower odds of good functional outcome (OR=0.44, 95% CI 0.21 to 0.93; P=0.03). More than one pass was not significantly associated with 90-day mRS score 0-2 (OR=0.46, 95% CI 0.15 to 1.43; P=0.17) or mortality (OR=2.03, 95% CI 0.81 to 5.08; P=0.13). FPE (one pass eTICI≥2c) and modified FPE (one pass extended thrombolysis in cerebral infarction ≥2b50) were not significantly associated with 90-day mRS 0-3, mortality, or symptomatic intracranial hemorrhage.

CONCLUSION

This analysis suggests that use of multiple passes is associated with worse outcomes in patients with large core infarcts.

Effects of reperfusion grade and reperfusion strategy on the clinical outcome: Insights from ESCAPE-NA1 trial

BACKGROUND

We evaluated the association of reperfusion quality and different patterns of achieved reperfusion with clinical and radiological outcomes in the ESCAPE NA1 trial.

METHODS

Data are from the ESCAPE-NA1 trial. Good clinical outcome [90-day modified Rankin Scale (mRS) 0-2], excellent outcome (90-day mRS0-1), isolated subarachnoid hemorrhage, symptomatic hemorrhage (sICH) on follow-up imaging, and death were compared across different levels of reperfusion defined by expanded Treatment in Cerebral Infarction (eTICI) Scale. Comparisons were also made between patients with (a) first-pass eTICI 2c3 reperfusion vs multiple-pass eTICI 2c3; (b) final eTICI 2b reperfusion vs eTICI 2b converted-to-eTICI 2c3; (c) sudden reperfusion vs gradual reperfusion if >1 pass was required. Multivariable logistic regression was used to test associations of reperfusion grade and clinical outcomes.

RESULTS

Of 1037 included patients, final eTICI 0-1 was achieved in 46 (4.4%), eTICI 2a in 76 (7.3%), eTICI 2b in 424 (40.9%), eTICI 2c in 284 (27.4%), and eTICI 3 in 207 (20%) patients. The odds for good and excellent clinical outcome gradually increased with improved reperfusion grades (adjOR ranging from 5.7-29.3 and 4.3-17.6) and decreased for sICH and death. No differences in outcomes between first-pass versus multiple-pass eTICI 2c3, eTICI 2b converted-to-eTICI 2c3 versus unchanged eTICI 2b and between sudden versus gradual eTICI 2c3 reperfusion were observed.

CONCLUSION

Better reperfusion degrees significantly improved clinical outcomes and reduced mortality, independent of the number of passes and whether eTICI 2c3 was achieved suddenly or gradually.

Optimizing suction force in mechanical thrombectomy: Priming the aspiration tubing with air versus saline

OBJECTIVE

We sought to investigate how priming the tube between air versus air mixed with saline ex vivo influenced suction force. We examined how priming the tube influenced peak suction force and time to achieve peak suction force between both modalities.

METHODS

Using a Dwyer Instruments (Dwyer Instruments Inc., Michigan City, IN, USA), INC Digitial Pressure Gauge, we were able to connect a .072 inch aspiration catheter to a rotating hemostatic valve and to aspiration tubing. We recorded suction force measured in negative inches of Mercury (inHg) over 10 iterations between having the aspiration tube primed with air alone versus air mixed with saline. A test was used to compare results between both modalities.

RESULTS

Priming the tube with air alone compared to air mixed with saline was found to have an increased average max suction force (-28.60 versus -28.20 in HG, p<0.01). We also identified a logarithmic curve of suction force across time in which time to maximal suction force was more prompt with air compared with air mixed with saline (13.8 seconds versus 21.60 seconds, p<0.01).

CONCLUSIONS

Priming the tube with air compared to air mixed with saline suggests that not only is increased maximal suction force achieved, but also the time required to achieve maximal suction force is less. This data suggests against priming the aspiration tubing with saline and suggests that the first pass aspiration primed with air may have the greatest suction force.

Benefits of First Pass Recanalization in Basilar Strokes Based on Initial Clinical Severity

PURPOSE

Randomized trials demonstrating the benefits of thrombectomy for basilar artery occlusions have enrolled an insufficient number of patients with a National Institutes for Health Stroke Scale (NIHSS) score < 10 and shown discrepant results for patients with an NIHSS > 20. Achieving a first pass recanalization (FPR) improves clinical outcomes in stroke. We aimed to evaluate the effect of the FPR on outcomes among basilar artery occlusion patients, characterized by prethrombectomy initial NIHSS score.

METHODS

We retrospectively analyzed the Endovascular Treatment in Ischemic Stroke (ETIS) registry of 279 basilar artery occlusion patients treated with thrombectomy from 6 participating centers. We compared the 90-day clinical outcomes of achieving a FPR versus no FPR, categorized by initial clinical severity: mild (NIHSS < 10), moderate (NIHSS 10-20) and severe (NIHSS > 20). We used Poisson regression with robust error variance to determine the effect of the NIHSS score on the association between FPR and outcomes.

RESULTS

The FPR patients with NIHSS < 10 or NIHSS 10-20 were more likely to have a favorable clinical outcome (modified Rankin scale, mRS 0-3) than non-FPR patients (relative risk, RR = 1.32, 95% confidence interval, CI: 1.04, 1.66, p-value = 0.0213, and RR = 1.79, 95% CI: 1.26, 2.53, p-value = 0.0011, respectively). A similar benefit was not found in patients with severe symptoms. We found a significantly lower risk of poor clinical outcome (mRS 4-6) in FPR patients with NIHSS 10-20, but not among patients with an NIHSS > 20.

CONCLUSION

Achieving a FPR in basilar artery occlusion patients with mild (NIHSS < 10) or moderate (NIHSS 10-20) symptoms is associated with better clinical outcomes, but not in patients with severe symptoms. These results support the importance of further clinical trials on the benefits of thrombectomy in severe strokes.

A Deep Learning Approach to Predict Recanalization First-Pass Effect following Mechanical Thrombectomy in Patients with Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Following endovascular thrombectomy in patients with large-vessel occlusion stroke, successful recanalization from 1 attempt, known as the first-pass effect, has correlated favorably with long-term outcomes. Pretreatment imaging may contain information that can be used to predict the first-pass effect. Recently, applications of machine learning models have shown promising results in predicting recanalization outcomes, albeit requiring manual segmentation. In this study, we sought to construct completely automated methods using deep learning to predict the first-pass effect from pretreatment CT and MR imaging.

MATERIALS AND METHODS

Our models were developed and evaluated using a cohort of 326 patients who underwent endovascular thrombectomy at UCLA Ronald Reagan Medical Center from 2014 to 2021. We designed a hybrid transformer model with nonlocal and cross-attention modules to predict the first-pass effect on MR imaging and CT series.

RESULTS

The proposed method achieved a mean 0.8506 (SD, 0.0712) for cross-validation receiver operating characteristic area under the curve (ROC-AUC) on MR imaging and 0.8719 (SD, 0.0831) for cross-validation ROC-AUC on CT. When evaluated on the prospective test sets, our proposed model achieved a mean ROC-AUC of 0.7967 (SD, 0.0335) with a mean sensitivity of 0.7286 (SD, 0.1849) and specificity of 0.8462 (SD, 0.1216) for MR imaging and a mean ROC-AUC of 0.8051 (SD, 0.0377) with a mean sensitivity of 0.8615 (SD, 0.1131) and specificity 0.7500 (SD, 0.1054) for CT, respectively, representing the first classification of the first-pass effect from MR imaging alone and the first automated first-pass effect classification method in CT.

CONCLUSIONS

Results illustrate that both nonperfusion MR imaging and CT from admission contain signals that can predict a successful first-pass effect following endovascular thrombectomy using our deep learning methods without requiring time-intensive manual segmentation.

Double Stent Retriever Technique for Mechanical Thrombectomy: A Systematic Review and Meta-Analysis

BACKGROUND

Mechanical thrombectomy using a double stent retriever technique has recently been described for the treatment of acute ischemic stroke, but its efficacy and safety are not well-established.

PURPOSE

The aim of this systematic review and meta-analysis was to evaluate reports of the use of a double stent retriever technique during the endovascular treatment of patients with ischemic stroke.

DATA SOURCES

The PubMed, EMBASE, Web of Science, and Scopus databases were searched to identify all studies (clinical trials, cohort series, and case reports) investigating the utility of a double stent retriever technique for the treatment of stroke. The study is reported in accordance with PRISMA 2020 guidelines and was prospectively registered in PROSPERO (CRD42023482691).

STUDY SELECTION

Seventeen studies involving a total of 128 patients with large-vessel occlusions predominantly in the anterior circulation (93.0%) were identified.

DATA ANALYSIS

Outcomes of interest were the prevalence of successful recanalization (modified TICI ≥2b) and a first-pass effect following the double stent retriever technique as well as complications such as iatrogenic dissections and SAH. Data were pooled using a random effects model.

DATA SYNTHESIS

The double stent retriever technique was used as a rescue strategy in occlusions refractory to conventional endovascular treatment in 68.7% (88/128) of patients and as a first-line strategy in 31.3% (40/128) of patients. The double stent retriever technique achieved an overall final modified TICI ≥2b in 92.6% cases, with a first-pass effect of 76.6%. The complication rate remained low, with 0.37% dissection and 1.56% SAH.

LIMITATIONS

Limitations of the study include the following: 1) a large number of case reports or small series, 2) a meta-analysis of proportions with no statistical comparison with a control group, and 3) the lack of access to patient-level data.

CONCLUSIONS

Our findings suggest that double stent retriever thrombectomy may be safe and associated with good recanalization outcomes, but prospective comparative studies are needed to determine which patients may benefit from this endovascular procedure.

Communicating Arteries and Leptomeningeal Collaterals: A Synergistic but Independent Effect on Patient Outcomes after Stroke

The collateral system is a compensatory mechanism activated in the acute phase of an ischemic stroke. It increases brain perfusion to the hypoperfused area. Arteries of the Willis' circle supply antegrade blood flow, while pial (leptomeningeal) arteries direct blood via retrograde flow. The aim of our retrospective study was to investigate the relationship between both collateral systems, computed tomography perfusion (CTP) values, and functional outcomes in acute stroke patients. Overall, 158 patients with anterior circulation stroke who underwent mechanical thrombectomy were included in the study. We analyzed the presence of communicating arteries and leptomeningeal arteries on computed tomography angiography. Patients were divided into three groups according to their collateral status. The main outcomes were the rate of functional independence 3 months after stroke (modified Rankin scale score, mRS) and mortality rate. Our study suggests that the collateral status, as indicated by the three groups (unfavorable, intermediate, and favorable), is linked to CT perfusion parameters, potential recuperation ratio, and stroke outcomes. Patients with favorable collateral status exhibited smaller core infarct and penumbra volumes, higher mismatch ratios, better potential for recuperation, and improved functional outcomes compared to patients with unfavorable or intermediate collateral status.

The effect of actuation frequency on clot integration with the Tigertriever device: A preliminary in vitro study

BACKGROUND

The Tigertriever stent retriever (Rapid Medical) can be actively expanded and contracted by the operator, which allows for several actuation-related parameters to be optimized to potentially improve device efficacy. These parameters have not yet been evaluated. We conducted a benchtop study to evaluate the effect of actuation frequency on clot integration within the stent.

METHODS

A Tigertriever 17 device was deployed within a biological clot analog placed in a straight tube. The device was actuated between the maximally contracted and maximally expanded states with three different frequencies: passive (one-time opening, n = 6), slow (20 s/cycle, n = 6), and fast (5 s/cycle, n = 7). A flat-detector CT scan was acquired, the clot and stent wires were segmented, and the boundaries of the clot and stent wires were calculated on each axial slice. The intersection between the stent and clot boundaries throughout the volume was defined as the volume of clot integrated within the stent. The clot integration factor (ratio of integrated clot volume to total clot volume) was then statistically compared between the three frequencies as an estimate of clot capture efficiency.

RESULTS

The clot integration factor was significantly higher (23% increase, p = 0.01) with the fast actuation as compared to the passive and slow actuations, with a post hoc test showing no difference (p > 0.05) between the passive and slow groups.

CONCLUSIONS

Faster actuation frequencies may result in improved clot integration with the Tigertriever device. This effect needs to be validated by clinical data.

Regression analysis of bleeding factors and the correlation between FPE and NLR after mechanical thrombectomy for acute anterior circulation large vessel occlusion

Acute anterior circulation large vessel occlusion refers to a blockage in the blood flow of one of the major blood vessels in the anterior (front) part of the brain. Acute anterior circulation large vessel occlusion can lead to a range of symptoms, including sudden headache, difficulty speaking or understanding speech, weakness or numbness on one side of the body and loss of vision in one eye. According to relevant data, mechanical thrombectomy in the treatment of the large vessel recanalization rate can reach 70%. However, hemorrhage is one of the serious complications after mechanical thrombectomy, and it is the main factor leading to the deterioration of neurological function and death of patients after large blood vessels. Therefore, the risk factors of bleeding in patients were analyzed before surgery, and effective prevention during and after surgery had positive significance for patients undergoing mechanical thrombectomy. This study uses regression analysis to analyze the correlation between bleeding factors and FPE and NLR after mechanical thrombectomy for acute anterior circulation large vessel occlusion. We retrospectively analyzed 81 patients with acute anterior circulation large vessel occlusion who underwent mechanical embolization in our hospital from September 2019 to January 2022 and separated them into a bleeding group (46 patients) and a non-bleeding group (35 patients) based on the presence or absence of bleeding after surgery.

Impact of Procedure Time on First Pass Effect in Mechanical Thrombectomy for Anterior Circulation Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

First pass effect (FPE) is a metric increasingly used to determine the success of mechanical thrombectomy (MT) procedures. However, few studies have investigated whether the duration of the procedure can modify the clinical benefit of FPE. We sought to determine whether FPE after MT for anterior circulation large vessel occlusion acute ischemic stroke is modified by procedural time (PT).

METHODS

A multicenter, international data set was retrospectively analyzed for anterior circulation large vessel occlusion acute ischemic stroke treated by MT who achieved excellent reperfusion (thrombolysis in cerebral infarction 2c/3). The primary outcome was good functional outcome defined by 90-day modified Rankin scale scores of 0-2. The primary study exposure was first pass success (FPS, 1 pass vs ≥2 passes) and the secondary exposure was PT. We fit-adjusted logistic regression models and used marginal effects to assess the interaction between PT (≤30 vs >30 minutes) and FPS, adjusting for potential confounders including time from stroke presentation.

RESULTS

A total of 1310 patients had excellent reperfusion. These patients were divided into 2 cohorts based on PT: ≤30 minutes (777 patients, 59.3%) and >30 minutes (533 patients, 40.7%). Good functional outcome was observed in 658 patients (50.2%). The interaction term between FPS and PT was significant ( P = .018). Individuals with FPS in ≤30 minutes had 11.5% higher adjusted predicted probability of good outcome compared with those who required ≥2 passes (58.2% vs 46.7%, P = .001). However, there was no significant difference in the adjusted predicted probability of good outcome in individuals with PT >30 minutes. This relationship appeared identical in models with PT treated as a continuous variable.

CONCLUSION

FPE is modified by PT, with the added clinical benefit lost in longer procedures greater than 30 minutes. A comprehensive metric for MT procedures, namely, FPE 30 , may better represent the ideal of fast, complete reperfusion with a single pass of a thrombectomy device.

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.

The Landscape of Biomimetic Nanovesicles in Brain Diseases

Brain diseases, such as brain tumors, neurodegenerative diseases, cerebrovascular diseases, and brain injuries, are caused by various pathophysiological changes, which pose a serious health threat. Brain disorders are often difficult to treat due to the presence of the blood-brain barrier (BBB). Biomimetic nanovesicles (BNVs), including endogenous extracellular vesicles (EVs) derived from various cells and artificial nanovesicles, possess the ability to penetrate the BBB and thus can be utilized for drug delivery to the brain. BNVs, especially endogenous EVs, are widely distributed in body fluids and usually carry various disease-related signal molecules such as proteins, RNA, and DNA, and may also be analyzed to understand the etiology and pathogenesis of brain diseases. This review covers the exhaustive classification and characterization of BNVs and pathophysiological roles involved in various brain diseases, and emphatically focuses on nanotechnology-integrated BNVs for brain disease theranostics, including various diagnosis strategies and precise therapeutic regulations (e.g., immunity regulation, disordered protein clearance, anti-neuroinflammation, neuroregeneration, angiogenesis, and the gut-brain axis regulation). The remaining challenges and future perspectives regarding the nanotechnology-integrated BNVs for the diagnosis and treatment of brain diseases are also discussed and outlined.

First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study

OBJECTIVE

We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes.

MATERIALS AND METHODS

In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months.

RESULTS

Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004).

CONCLUSION

Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Intravenous thrombolysis before thrombectomy in acute ischemic stroke: a dual centre retrospective cohort study

First pass effect (FPE) is a successful recanalization (mTICI ≥ 2b) after the first trial of thrombectomy. It is associated with good functional outcomes. Few studies discussed the effect of BT (bridging therapy: combined I.V. thrombolysis and mechanical thrombectomy) on FPE and clinical outcomes. In our study, we would like to report the effect of MT with or without preceding IVT on FPE and the functional outcome of AIS (Acute Ischemic Stroke) of anterior circulation in real practice. A dual-center retrospective cohort study enrolled 201 patients with AIS of anterior circulation and was divided into a bridging therapy (BT) group of 150 patients who received alteplase preceding thrombectomy, and a direct mechanical thrombectomy (dMT) group of 51 patients. Comparisons between both groups regarding the clinical and radiological outcome. Early better clinical outcome (mRS ≤ 2) at day seven with BT group (39.3%) rather than dMT (23.5%) with P value = 0.044. No significant differences as regard puncture to revascularization time, successful revascularization (mTICI) ≥ 2b and FPE between both groups (P value: 0.328, 0.538, and 0.708, respectively). No differences as regards hemorrhagic transformation, mortality rate, and 90-day favorable outcome between both groups (P value 0.091, 0.089, and 0.192, respectively). BT might have better early outcome than dMT but no difference as regards 90-day favorable outcomes, mortality, sICH, FPE, recanalization rate and procedure time. It might be reasonable to go directly to mechanical thrombectomy without IVT for AIS with large vessel occlusion.