Effective use of balloon guide catheters in reducing incidence of mechanical thrombectomy related distal embolization

Placing the balloon-guide catheter in the high cervical segment of the internal carotid artery is associated with improved recanalization

BACKGROUND

Mechanical thrombectomy (MT) is part of the standard of care for stroke treatment, and improving its efficacy is one of the main objectives of clinical investigation. Of importance is placement of the distal end of balloon-guided catheters (BGC). We aim to determine if this influences outcomes.

METHODS

We analyzed data from the ASSIST Registry, an international, multicenter prospective study of 1492 patients. We divided patients treated with BGC according to the placement of the BGC: low cervical (LCG (the lower 2/3 of cervical internal carotid artery (ICA)) or high cervical (HCG (upper 1/3 of cervical ICA, petro-lacerum or higher)). We analyzed characteristics and outcomes overall and stratified on the primary MT technique: Stent-Retriever only (SR Classic), Combined use of aspiration catheter and SR (Combined), and Direct Aspiration (ADAPT).

RESULTS

Our study included 704 subjects -323 in the low cervical and 381 in the high cervical groups. Statistical differences were seen in the proportion of females and tandem lesions (both higher for LCG). Placing the BGC in the high cervical segment is associated with better recanalization rates (expanded treatment in cerebral infarction (eTICI) score of 2c-3) at the end of the procedure (P<0.0001) and shorter procedures (P=0.0005). After stratifying on the three primary techniques (SR Classic, Combined, and ADAPT), placing the BGC in the high segment is associated with a better first-pass effect (FPE), less distal emboli, and better clinical outcomes in the SR Classic technique.

CONCLUSIONS

Placing the distal end of the BGC at the high cervical segment or higher is associated with better recanalization.

Comparison of balloon guide catheter versus non-balloon guide catheter for mechanical thrombectomy in patients with distal medium vessel occlusion

BACKGROUND

Several studies have established the safety and efficacy of balloon guide catheters (BGCs) for large vessel occlusions. However, the utility of BGCs remains largely unexplored for distal medium vessel occlusions (DMVOs). In this study, we aim to compare the outcomes of BGC vs. Non-BGC in patients undergoing mechanical thrombectomy (MT) for DMVO.

METHOD

This retrospective study from the Stroke Thrombectomy and Aneurysm Registry (STAR) encompassed adult patients with acute anterior cerebral artery, posterior cerebral artery, and middle cerebral artery-M2-3-4 occlusions. Procedure times, safety, recanalization, and neurological outcomes were compared between the two groups, with subgroup analysis based on first-line thrombectomy techniques.

RESULTS

A total of 1508 patients were included, with 231 patients (15.3%) in the BGC group and 1277 patients (84.7%) in the non-BGC group. The BGC group had a lower modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2C (43.2% vs 52.7%, P=0.01), longer time from puncture to intracranial access (15 vs 8 min, P<0.01), and from puncture to final recanalization (97 vs 34 min, P<0.01). In the Solumbra subgroup, the first pass effect (FPE) rate was lower in the BGC group (17.4% vs 30.7%, P=0.03). Regarding clinical outcomes, the BGC group had a lower rate of distal embolization (8.8% vs 14.9%, P=0.03).

CONCLUSION

Our study found that use of BGC in patients with DMVO was associated with lower mTICI scores, decreased FPE rates, reduced distal embolization, and longer procedure times.

Comparison of Balloon Guide Catheters and Standard Guide Catheters for Acute Ischemic Stroke: An Updated Systematic Review and Meta-analysis

OBJECTIVE

The objective of this study was to update our 2021 systematic review and meta-analysis which reported that balloon guide catheters (BGC) are associated with superior clinical and angiographic outcomes compared to standard guide catheters for treatment of acute ischemic stroke.

METHODS

We conducted a systematic review of 7 electronic databases to identify literature published between January 2010 and September 2023 reporting BGC versus non-BGC approaches. Primary outcomes were final modified thrombolysis in cerebral infarction (mTICI) ≥2b, first-pass effect (mTICI ≥2c on first pass), and modified Rankin scale 0-2 at 90 days. The risk of bias was assessed using the Newcastle Ottawa Scale. A separate random effects model was fitted for each outcome. Subgroup analyses by first-line approach were conducted.

RESULTS

Twenty-four studies comprising 8583 patients were included (4948 BGC; 3635 non-BGC; 1561 BGC + Stent-retriever; 1297 non-BGC + Stent-retriever). Nine studies had low risk of bias, 3 were moderate risk, and 12 were high risk. Patients treated with BGCs had higher odds of achieving mTICI 2b/3, first-pass effect mTICI 2c/3, and modified Rankin scale 0-2 at 90 days (P < 0.001). The number of patients needed to treat in order to achieve one additional successful recanalization is 17. BGC + Stent-retriever was associated with higher odds of mTICI≥2b, 90-day modified Rankin scale 0-2, and reduced odds of 90-day mortality compared to non-BGC + Stent-retrievers. The main limitation was the absence of randomized trials.

CONCLUSIONS

These findings corroborate our previous results suggesting that MT using BGCs is associated with better safety and effectiveness outcomes for acute ischemic stroke, especially BGC + Stent-retrievers.

Predictive Factors of First-Pass Effect in Patients Who Underwent Successful Endovascular Thrombectomy for Emergent Large Vessel Occlusion

OBJECTIVE

The primary treatment goal of current endovascular thrombectomy (EVT) for emergent large-vessel occlusion (ELVO) is complete recanalization after a single maneuver, referred to as the 'first-pass effect' (FPE). Hence, we aimed to identify the predictive factors of FPE and assess its effect on clinical outcomes in patients with ELVO of the anterior circulation.

METHODS

Among the 129 patients who participated, 110 eligible patients with proximal ELVO (intracranial internal carotid artery and proximal middle cerebral artery) who achieved successful recanalization after EVT were retrospectively reviewed. A comparative analysis between patients who achieved FPE and all others (defined as a non-FPE group) was performed regarding baseline characteristics, clinical variables, and clinical outcomes. Multivariate logistic regression analyses were subsequently conducted for potential predictive factors with p<0.10 in the univariate analysis to determine the independent predictive factors of FPE.

RESULTS

FPE was achieved in 31 of the 110 patients (28.2%). The FPE group had a significantly higher level of functional independence at 90 days than did the non-FPE group (80.6% vs. 50.6%, p=0.002). Pretreatment intravenous thrombolysis (IVT) (odds ratio [OR], 3.179; 95% confidence interval [CI], 1.025-9.861; p=0.045), door-to-puncture (DTP) interval (OR, 0.959; 95% CI, 0.932-0.987; p=0.004), and the use of balloon guiding catheter (BGC) (OR, 3.591; 95% CI, 1.231-10.469; p=0.019) were independent predictive factors of FPE.

CONCLUSION

In conclusion, pretreatment IVT, use of BGC, and a shorter DTP interval were positively associated with FPE, increasing the chance of acquiring better clinical outcomes.

Predictors of Emboli in Mechanical Thrombectomy for Anterior Circulation Stroke

OBJECTIVE

Emboli commonly occurs in mechanical thrombectomy (MT). The objective of this study was to analyze predicting factors of emboli after MT.

METHODS

Patients who underwent MT with successful reperfusion for anterior circulation occlusion were enrolled. Emboli included distal emboli at digital subtraction angiography (DSA) and unexpected embolic infarct on diffusion-weighted image (DWI) without distal emboli at DSA. Baseline characteristics, procedural details, angiographic outcomes, and clinical outcomes were reviewed. Multivariable analyses were performed to evaluate predictive factors for the occurrence of emboli.

RESULTS

Of 601 patients, 149 (24.8%) patients had distal emboli at DSA, and 169 (28.1%) patients had unexpected embolic infarction on DWI even without distal emboli at DSA. A total of 318 (52.9%) patients were enrolled in the embolic group, and 283 (47.1%) patients were assigned to the non-embolic group. In multivariate analysis, larger microcatheter (OR 1.26, 95% CI 1.12-1.94; p = 0.047), clot passage (OR 1.33, 95% CI 1.07-1.87; p = 0.041), use of balloon guide catheter (BGC) (OR 0.70, 95% CI 0.52-0.92; p = 0.014), early ballooning of BGC (OR 0.68, 95% CI 0.50-0.90; p = 0.009), and longer stent retriever (OR 0.72, 95% CI 0.54-0.90; p = 0.029) were associated with occurrence of emboli.

CONCLUSION

MT with only a stent retriever, use of a larger microcatheter, and clot passage might increase the risk of emboli. In contrast, contact aspiration thrombectomy, use of BGC, early ballooning of BGC, and use of longer stent retrievers could reduce the chance of emboli.

Distal placement of balloon guide catheter facilitates stent-retriever mechanical thrombectomy for acute ischemic stroke in the anterior circulation

PURPOSE

Although balloon guide catheters (BGCs) have been demonstrated to improve recanalization and functional outcomes by enabling proximal flow control and forced aspiration during mechanical thrombectomy (MT), the significance of the BGC location has been overlooked. We evaluated the impact of BGC location during MT for anterior circulation acute ischemic stroke (AIS).

METHODS

Patients were divided into the proximal and distal BGC groups according to the BGC tip location relative to the lower margin of the C1 vertebral body. Endovascular and clinical outcomes were compared between the two groups, including subgroup analyses of the two types of extracranial internal carotid artery (ICA) anatomy, categorized based on cerebral angiography.

RESULTS

A total of 124 patients were analyzed, with 62 each in the proximal and distal BGC placement groups. The distal BGC group had higher rates of first-pass recanalization (FPR) (38.7% vs. 17.7%, P = 0.009) and favorable outcomes (64.5% vs. 46.8%, P = 0.047) with shorter procedure time (47.5 min vs. 65 min, P = 0.001) and fewer distal embolization (3.2% vs. 12.9%, P = 0.048) than the proximal BGC group. FPR was also more frequently achieved in the distal BGC group of patients with tortuous ICA (37.0% vs. 12.5%, P = 0.029). Multivariate analysis showed that distal BGC placement was an independent predictor of FPR (odds ratio, 3.092; 95% confidence interval, 1.326-7.210; P = 0.009).

CONCLUSION

Distal BGC placement facilitates MT for AIS in the anterior circulation. Therefore, we suggest distal BGC placement to maximize the effect of thrombectomy, even for tortuous extracranial ICA.

The balloon occlusion sheath for stroke (BOSS) balloon guide catheter for stroke intervention: Safety and technical success

BACKGROUND

We describe the first-in-human experience using the Balloon Occlusion Stroke Sheath (BOSSTM) balloon-guide catheter to perform stroke thrombectomy in 50 consecutive patients enrolled in the Flow Arrest Safety and Technical success with balloon-guide catheters trial. This aspiration system includes a novel 9.4F balloon-guide catheter conduit for the insertion and guidance of catheters with a balloon providing temporary flow arrest.

METHODS

The Flow Arrest Safety and Technical success with balloon-guide catheter trial is a single-arm, prospective, multi-center, non-randomized, observational registry evaluating the use of the market-released BOSSTM balloon-guide catheter in adult patients diagnosed with an acute ischemic stroke attributable to large vessel occlusion. The purpose of the current trial was to assess the safety and technical success associated with the use of the BOSSTM balloon-guide catheter.

RESULTS

Fifty patients met inclusion criteria with a mean baseline National Institutes of Health Stroke Scale (NIHSS) of 16. Treatment devices, including aspiration and stent retriever devices, were used in a total of 88 passes. The BOSSTM balloon-guide catheter was compatible with all stroke thrombectomy treatment devices used in 98% (49/50) of procedures. Balloon inflation and flow arrest were achieved in 100% (50/50) and 98% (49/50) of cases, respectively. Balloon deflation and retraction were observed in 100% (50/50) of cases. Successful reperfusion (modified thrombolysis in cerebral infarction score > 2b) was achieved in 100% of cases with single-pass reperfusion achieved in 62% (31/50) of cases.

CONCLUSIONS

The BOSSTM balloon-guide catheter is a safe and technically effective adjunctive device for mechanical thrombectomy of acute ischemic stroke due to large vessel occlusion.

A review of mechanical thrombectomy techniques for acute ischemic stroke

Mechanical thrombectomy is established as standard of care in the management of acute ischemic stroke due to large vessel occlusion and evidence-based guidelines for mechanical thrombectomy have been defined. As research continues to further expand the eligibility criteria for thrombectomy and the number of thrombectomy procedures increase worldwide, there is also growing focus on innovation of thrombectomy devices, procedural techniques, and related outcomes. Thrombectomy primarily involves use of stent retrievers and distal aspiration techniques, but variations and different combinations of techniques have been reported. As this is a rapidly evolving area in stroke management, there is debate as to which, if any, of these techniques leads to improved clinical outcomes over another and there is a lack of data comparing them. In this review, currently published and distinct techniques of mechanical thrombectomy are described methodically along with illustrations to aid in understanding the subtle differences between the techniques. The perceived benefits of each variation are discussed.

CT-based thrombus radiomics nomogram for predicting secondary embolization during mechanical thrombectomy for large vessel occlusion

Background and aims

Secondary embolization (SE) during mechanical thrombectomy (MT) for cerebral large vessel occlusion (LVO) could reduce the anterior blood flow and worsen clinical outcomes. The current SE prediction tools have limited accuracy. In this study, we aimed to develop a nomogram to predict SE following MT for LVO based on clinical features and radiomics extracted from computed tomography (CT) images.

Materials and methods

A total of 61 patients with LVO stroke treated by MT at Beijing Hospital were included in this retrospective study, of whom 27 developed SE during the MT procedure. The patients were randomly divided (7:3) into training (n = 42) and testing (n = 19) cohorts. The thrombus radiomics features were extracted from the pre-interventional thin-slice CT images, and the conventional clinical and radiological indicators associated with SE were recorded. A support vector machine (SVM) learning model with 5-fold cross-verification was used to obtain the radiomics and clinical signatures. For both signatures, a prediction nomogram for SE was constructed. The signatures were then combined using the logistic regression analysis to construct a combined clinical radiomics nomogram.

Results

In the training cohort, the area under the receiver operating characteristic curve (AUC) of the nomograms was 0.963 for the combined model, 0.911 for the radiomics, and 0.891 for the clinical model. Following validation, the AUCs were 0.762 for the combined model, 0.714 for the radiomics model, and 0.637 for the clinical model. The combined clinical and radiomics nomogram had the best prediction accuracy in both the training and test cohort.

Conclusion

This nomogram could be used to optimize the surgical MT procedure for LVO based on the risk of developing SE.

Retrograde Angiography to Detect Dropped Thrombus in Mechanical Thrombectomy

OBJECTIVE

The risk of embolization to distal territory or to new territory in mechanical thrombectomy remains a major issue despite advancements in technological device. This condition can be caused by a large and firm dropped thrombus without passing through a guiding catheter during stent retriever or aspiration catheter withdrawal. This report introduced a novel technique referred to as retrograde angiography to detect dropped thrombus.

METHODS

The retrograde angiography to detect dropped thrombus technique is a kind of retrograde angiography that consists of a contrast medium injection via a distal microcatheter and aspiration through an inflated balloon-guiding catheter. This method was used to detect dropped thrombus at the balloon-guiding catheter tip when back flow was blocked from the balloon-guiding catheter after stent retriever or aspiration catheter withdrawal. We retrospectively reviewed four consecutive patients who underwent the retrograde angiography to detect dropped thrombus technique during mechanical thrombectomy for acute ischemic stroke due to large vessel occlusion in the anterior circulation between January 2018 and January 2021.

RESULTS

Three of four patients had dropped thrombus, which was diagnosed with the technique and retrieved completely with subsequent procedures while maintaining the balloon-guiding catheter inflated. None of the patients experienced embolization to distal territory/embolization to new territory, and a successful reperfusion was achieved in all four cases.

CONCLUSIONS

The retrograde angiography to detect dropped thrombus is a technique to detect a dropped thrombus at the balloon-guiding catheter tip and allows us to retrieve it with subsequent mechanical thrombectomy procedures while maintaining the balloon-guiding catheter inflated and it may be useful for reducing the risk of embolization to distal territory/embolization to new territory.

Comparing the Conventional and Balloon-Guided Catheter-Assisted SWIM Technology for the Treatment of Acute Ischemic Stroke

Objective

Acute ischemic stroke is common in elder patients. This study investigates whether using the balloon-guided catheter (BGC) would improve the effect of stent thrombectomy (Solitaire FR With Intracranial Support Catheter for Mechanical Thrombectomy, SWIM) for patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO).

Method

The data of 209 patients with AIS-LVO underwent SWIM were collected retrospectively from January 2017 to June 2021. These patients were divided into two groups based on whether they used of BGC or not. The propensity score matching (PSM) analysis was used to compare the differences in the first pass effect (FPE), successful recanalization, embolus escape rate, symptomatic intracranial hemorrhage (sICH), 90-day clinical favorable outcome, 90-day all-cause mortality, and complications in the patients treated with SWIM combined with balloon-guided catheter or conventional catheter.

Results

Among the 209 patients, 44 patients were treated with BGC and 165 patients were not. After matching, a total of 111 patients were included. The results showed that there was no statistical difference in FPE (35.1% in non-BGC group compared to 24.3% in BGC group, matched RR, 0.59; 95% CI, 0.24–1.44), successful recanalization (89.2 vs. 91.9%, matched RR, 1.37; 95%CI, 0.34–5.51), embolus escape (6.8 vs. 8.1%, matched RR, 1.22; 95%CI, 0.28–5.40), sICH (8.1 vs. 13.5%; matched RR, 1.77; 95%CI 0.50–6.24), 90-day clinical favorable outcome (48.7 vs. 54.1%, matched RR, 1.11; 95%CI 0.51–2.46), 90-day all-cause mortality (17.6 vs. 21.6%, matched RR, 1.29; 95%CI 0.48–3.47), and the incidence of complications (6.8 vs. 5.4%, matched RR, 0.79 95%CI 0.15–4.27). These results indicate that using SWIM as the first-line treatment for patients with AIS-LVO, there is no statistical significance in FPE, final successful recanalization, distal emboli, sICH, procedural time, 90-day favorable outcome, 90-day mortality, and complications with or without BGC.

Conclusion

Balloon-guided catheter does not affect the result of using SWIM as the first-line treatment for patients with AIS-LVO. Our results will guide daily practice, with the adoption of the use of a guided catheter without a balloon.

Effectiveness of Anchoring with Balloon Guide Catheter and Stent Retriever in Difficult Mechanical Thrombectomy for Large Vessel Occlusion

Objective

A distal navigation of a large bore aspiration catheter during mechanical thrombectomy (MT) is important. However, delivering a large bore aspiration catheter is difficult to a tortuous or atherosclerotic artery. We report the experience of anchoring with balloon guide catheter (BGC) and stent retriever to facilitate the passage of an aspiration catheter in MT.

Methods

When navigating an aspiration catheter failed with a conventional co-axial microcatheter delivery, an anchoring technique was used. Two types of anchoring technique were applied to facilitate distal navigation of a large bore aspiration catheter during MT. First, a passage of aspiration catheter was attempted with a proximal BGC anchoring technique. If this technique also failed, another anchoring technique with distal stent retriever was tried. Consecutive patients who underwent MT with an anchoring technique were identified. Details of procedure, radiologic outcomes, and safety variables were evaluated.

Results

A total of 67 patients underwent MT with an anchoring technique. Initial trial of aspiration catheter passage with proximal BGC anchoring technique was successful for 35 patients (52.2%) and the second trial with distal stent retriever anchoring was successful for 32 patients (47.8%). Overall, navigation of a large bore aspiration catheter was successful for all patients (100%) without any procedure related complications.

Conclusion

Our study showed the usefulness of anchoring technique with proximal BGC and distal stent retriever during MT, especially in those with an unfavorable anatomical structure. This technique could be an alternative option for delivering an of aspiration catheter to a distal location.

Endovascular Treatment for Posterior Circulation Stroke: Ways to Maximize Therapeutic Efficacy

The efficacy of endovascular treatment (EVT) in patients with posterior circulation stroke has not been proven. Two recent randomized controlled trials failed to show improved functional outcomes after EVT for posterior circulation stroke (PC-EVT). However, promising results for two additional randomized controlled trials have also been presented at a recent conference. Studies have shown that patients undergoing PC-EVT had a higher rate of futile recanalization than those undergoing EVT for anterior circulation stroke. These findings call for further identification of prognostic factors beyond recanalization. The significance of baseline clinical severity, infarct volume, collaterals, time metrics, core-penumbra mismatch, and methods to accurately measure these parameters are discussed. Furthermore, their interplay on EVT outcomes and the potential to individualize patient selection for PC-EVT are reviewed. We also discuss technical considerations for improving the treatment efficacy of PC-EVT.

Repeated-Manual Aspiration with Maximum Pressure (r-MAX): A New Technique of Mechanical Thrombectomy Using Syringe Aspiration

Objective

We report a new contact aspiration technique using syringe aspiration called repeated-manual aspiration with maximum pressure (r-MAX).

Case Presentation

From January 2020 to May 2021, 18 patients underwent mechanical thrombectomy with r-MAX for occlusion of the internal carotid artery, the first division of the middle cerebral artery (M1), and basilar artery occlusion. In this method, the aspiration catheter is first guided to the occlusion site, and then, two VacLok syringes are connected to the aspiration catheter. Next, the three-way stopcock is released in one direction. After 15 seconds, the direction of the three-way stopcock is switched. In the meantime, negative pressure is reapplied through the syringe, and the direction of the three-way stopcock is switched again. After reapplying negative pressure through the syringe and switching the three-way stopcock two more times, the aspiration catheter is removed. First-pass thrombolysis in cerebral infarction (TICI) scale 3 recanalization was achieved in 11 out of 18 patients (61.1%). In all, 11 patients (61.1%) achieved modified Rankin Scale scores of 0-2 at 90 days. Asymptomatic hemorrhage was observed in two patients (11.1%), and no patients had symptomatic hemorrhage.

Conclusion

The r-MAX technique using syringe aspiration can be employed as one of the methods of contact aspiration.

Reperfusion Therapies for Children With Arterial Ischemic Stroke

ABSTRACT

Modern hyperacute reperfusion therapies including intravenous thrombolysis and mechanical thrombectomy have transformed the management of arterial ischemic stroke (AIS) in adults. Multiple randomized clinical trials have demonstrated that these therapies enable remarkable improvements in clinical outcome for properly selected patients with AIS. Because pediatric patients were excluded from predicate clinical trials, there is a conspicuous lack of data to guide selection of therapies and inform age-adjusted and pathology-oriented treatment modifications for children. Specifically, technical guidance concerning treatment eligibility, drug dosing, and device implementation is lacking. This review aims to outline important features that differentiate pediatric AIS from adult AIS and provide practical strategies that will assist the stroke specialist with therapeutic decision making.

Addition of intracranial aspiration to balloon guide catheter does not improve outcomes in large vessel occlusion anterior circulation stent retriever based thrombectomy for acute stroke

BACKGROUND

Balloon guide catheter (BGC) in stent retriever based thrombectomy (BGC+SR) for patients with large vessel occlusion strokes (LVOS) improves outcomes. It is conceivable that the addition of a large bore distal access catheter (DAC) to BGC+SR leads to higher efficacy. We aimed to investigate whether the combined BGC+DAC+SR approach improves angiographic and clinical outcomes compared with BGC+SR alone for thrombectomy in anterior circulation LVOS.

METHODS

Consecutive patients with anterior circulation LVOS from June 2019 to November 2020 were recruited from the ROSSETTI registry. Demographic, clinical, angiographic, and outcome data were compared between patients treated with BGC+SR alone versus BGC+DAC+SR. The primary outcome was first pass effect (FPE) rate, defined as near complete/complete revascularization (modified Thrombolysis in Cerebral Infarction (mTICI) 2c-3) after single device pass.

RESULTS

We included 401 patients (BGC+SR alone, 273 (66.6%) patients). Patients treated with BGC+SR alone were older (median age 79 (IQR 68-85) vs 73.5 (65-82) years; p=0.033) and had shorter procedural times (puncture to revascularization 24 (14-46) vs 37 (24.5-63.5) min, p<0.001) than the BGC+DAC+SR group. Both approaches had a similar FPE rate (52% in BGC+SR alone vs 46.9% in BGC+DAC+SR, p=0.337). Although the BGC+SR alone group showed higher rates for final successful reperfusion (mTICI ≥2b (86.8% vs 74.2%, p=0.002) and excellent reperfusion, mTICI ≥2 c (76.2% vs 55.5%, p<0.001)), there were no significant differences in 24 hour National Institutes of Health Stroke Scale score or rates of good functional outcome (modified Rankin Scale score of 0-2) at 3 months across these techniques.

CONCLUSIONS

Our data showed that addition of distal intracranial aspiration catheters to BGC+SR based thrombectomy in patients with acute anterior circulation LVO did not provide higher rates of FPE or improved clinical outcomes.

Clinical and Procedural Outcomes with or without Balloon Guide Catheters during Endovascular Thrombectomy in Acute Ischemic Stroke: A Systematic Review and Meta-analysis with First-line Technique Subgroup Analysis

BACKGROUND

Balloon guide catheters are increasingly used to improve clot retrieval by temporarily stopping proximal blood flow during endovascular thrombectomy.

PURPOSE

Our aim was to provide a summary of the literature comparing the procedural and clinical outcomes of endovascular thrombectomy with or without balloon guide catheters, depending on the first-line technique used.

DATA SOURCES

We used PubMed/MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews.

STUDY SELECTION

We chose studies that compared using balloon guide catheters with not using them.

DATA ANALYSIS

Random effects meta-analysis was performed to compare the procedural outcomes measured as the first-pass effect, successful reperfusion, number of passes, procedural duration, arterial puncture to reperfusion time, distal emboli, and clinical outcomes.

DATA SYNTHESIS

Overall, a meta-analysis of 16 studies (5507 patients, 50.8% treated with balloon guide catheters and 49.2% without them) shows that the use of balloon guide catheters increases the odds of achieving a first-pass effect (OR = 1.92; 95% CI, 1.34-2.76; P < .001), successful reperfusion (OR = 1.85; 95% CI, 1.42-2.40; P < .001), and good functional outcome (OR =1.48; 95% CI, 1.27-1.73; P < .001). Balloon guide catheters reduce the number of passes (mean difference = -0.35; 95% CI, -0.65 to -0.04; P = .02), procedural time (mean difference = -19.73; 95% CI, -34.63 to -4.83; P = .009), incidence of distal or new territory emboli (OR = 0.5; 95% CI, 0.26-0.98; P = .04), and mortality (OR = 0.72; 95% CI, 0.62-0.85; P < .001). Similar benefits of balloon guide catheters are observed when the first-line technique was a stent retriever or contact aspiration, but not for a combined approach.

LIMITATIONS

The analysis was based on nonrandomized trials with a moderate risk of bias.

CONCLUSIONS

Current literature suggests improved clinical and procedural outcomes associated with the use of balloon guide catheters during endovascular thrombectomy, especially when using the first-line stent retriever.

Comparison of Balloon Guide Catheters and Standard Guide Catheters for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Balloon guide catheters (BGCs) are designed to induce flow arrest during mechanical thrombectomy procedures for acute ischemic stroke due to large-vessel occlusion and have been associated with improved clinical and angiographic outcomes. We conducted a systematic review and meta-analysis evaluating the relative technical and clinical outcomes associated with BGC versus non-BGC approaches.

METHODS

A systematic review of clinical literature using the PubMed database was undertaken to identify multiarm studies published between 2010 and 2021 reporting the use of BGC versus non-BGC approaches for stroke treatment. Data collected included complete recanalization (thrombolysis in cerebral infarction, TICI), first-pass effect TICI 3, puncture-to recanalization time, number of endovascular attempts, distal embolization, symptomatic intracerebral hemorrhage, 90-day modified Rankin Scale score 0-2, and 90-day mortality. Subgroup analyses assessed the impact of treatment device (stent-retrievers, contact aspiration, combination therapy, and not specified/other). A random effects model was fit for each outcome measure.

RESULTS

Fifteen studies were included. Compared with non-BGC approaches, patients treated with BGCs had greater odds of TICI 3 (odds ratio [OR] 1.57; 95% confidence interval [95% CI] 1.08-2.29) and first-pass effect TICI 3 (OR 3.63; 95% CI 2.34-5.62), reduced puncture-to-revascularization time (mean difference -7.8; 95% CI -13.3 to -2.2), fewer endovascular attempts (mean difference -0.47; 95% CI -0.68 to -0.26), reduced odds of distal emboli (OR 0.34; 95% CI 0.17-0.71) and symptomatic intracerebral hemorrhage (OR 0.66; 95% CI 0.51-0.86), greater odds of 90-day modified Rankin Scale score 0-2 (OR 1.51; 95% CI 1.27-1.79), and reduced odds of mortality (OR 0.69; 95% CI 0.57-0.82).

CONCLUSIONS

BGCs yield superior technical and clinical outcomes while reducing patient complications.

Walrus Balloon Guide Catheter for Stroke Intervention: Technical Considerations and Clinical Outcomes

BACKGROUND

The use of balloon guide catheters (BGCs) for proximal flow arrest during neurointerventional procedures has been limited owing to the incompatibility of BGCs with large-bore aspiration catheters and difficulty in device navigation. The objective of our study was to describe the use of the Walrus catheter (Q'Apel Medical, Fremont, California, USA), a new 8F BGC, with a variety of aspiration catheters and procedures requiring flow arrest.

METHODS

Consecutive cases using Walrus BGCs for proximal flow arrest during mechanical thrombectomy for acute stroke cases were recorded. The procedure indication, vessel occlusion site, technique, first-pass effect (modified thrombolysis in cerebral infarction score of 2C or 3 after the first recanalization attempt), and complications were recorded and evaluated statistically.

RESULTS

Our study included 57 patients who had undergone mechanical thrombectomy. In addition to mechanical thrombectomy, the Walrus BGC was used in conjunction with the following techniques: stent retrieval in 2 patients (3.5%), stent retrieval followed by aspiration (Solumbra technique) in 41 (71.9%), and aspiration followed by stent retrieval in 14 patients (24.6%). Eight different aspiration catheters were used in 56 of these 57 procedures. The first-pass effect (modified thrombolysis in cerebral infarction score of 2C and 3) was achieved in 36 (63.2%) of 57 procedures. Two patients (3.5%) had experienced intraoperative complications (symptomatic intracerebral hemorrhage) and one patient (1.8%) had died in-hospital.

CONCLUSIONS

Our results have demonstrated that the Walrus BGC is a highly navigable 8F guide catheter compatible with most available aspiration catheters. Owing to its compatibility with most available aspiration catheters and ease of use, the Walrus BGC is a valuable addition to the tools available for mechanical thrombectomy.

Walrus large bore guide catheter impact on recanalization first pass effect and outcomes: the WICkED study

BACKGROUND

The use of a balloon-guide catheter (BGC) in acute stroke treatment has been widely adopted after demonstrating optimized procedure metrics and outcomes. Initial technical constraints of previous devices included catheter stiffness and smaller inner diameters. We aim to evaluate the performance and safety of the Walrus BGC, a variable stiffness catheter with a large bore 0.087 inch inner diameter (ID), via the the WICkED study (Walrus Large Bore guide Catheter Impact on reCanalization first pass Effect anD outcomes).

METHODS

This is a retrospective, site adjudicated, multicenter study on consecutive patients with large vessel occlusion treated with the Walrus BGC. Baseline characteristics, procedural outcomes and functional outcomes were analyzed.

RESULTS

A total of 338 patients met the inclusion criteria. The Walrus was successfully tracked into distal vasculature and allowed therapeutic device delivery in all but 3 cases (0.9%). Large aspiration catheters ≥0.070 inch ID were used in 71.9% of cases. Stent retriever thrombectomy was used as the first-line modality in 59.2% and thromboaspiration in 40.8% of cases. The successful recanalization rate (modified treatment in cerebral ischemia (mTICI) 2b/3) was 94.4%, with 64.8% of the patients achieving mTICI 2b/3 after the first pass. The Walrus-related adverse event rate was 0.6%, corresponding to two vessel dissections. Functional independence was 50% (126/252) and mortality 25% (63/252). Unfavorable outcomes were more likely in older patients, who had unsuccessful reperfusion, longer procedure times, and a higher mean number of passes.

CONCLUSION

In acute ischemic stroke patients presenting with large vessel occlusion, the Walrus BGC demonstrated excellent navigability and safety profile, allowed the accommodation of leading large bore aspiration catheters, and demonstrated high vessel recanalization rates.

Maximizing the catheter-to-vessel size optimizes distal flow control resulting in improved revascularization in vitro for aspiration thrombectomy

Background

Balloon guide catheters (BGCs) achieve proximal flow control during thrombectomy but antegrade intracranial flow often persists via the Circle of Willis. Closely sizing an aspiration catheter to the target vessel might achieve greater flow control and improve technical performance. Our objective was to measure the impact of aspiration catheter size on distal flow control and flow reversal with and without the use of BGCs. Clot retrieval testing was performed to establish the impact of these parameters on revascularization.

Methods

An in vitro thrombectomy model replicated in vivo conditions. Flow was measured continuously using ultrasonic flow sensors placed 20 cm distal to the catheter tip in the middlel cerebral artery (MCA). Four aspiration catheters of increasing size were evaluated: ACE 60 and 64 (Penumbra), SOFIA Plus (MicroVention), and Millipede 088 (Perfuze). Two clot analog types (red blood cell-rich and fibrin/platelet-rich) were used for clot retrieval testing.

Results

The larger area of the ‘superbore’ Millipede 088 catheter resulted in a larger reduction in antegrade flow than standard aspiration catheters, even when the latter were combined with a BGC. During aspiration, 6Fr catheters were unable to cause flow reversal in the distal MCA while the Millipede 088 achieved significant distal flow reversal (−146 mL/min) (P<0.0001*) (*denotes significance). The solo use of Millipede 088 resulted in better recanalization outcomes and significantly reduced distal emboli for internal carotid artery (P=0.015*) and MCA (P=0.014*) occlusions compared with all other devices and combinations.

Conclusions

Maximizing the catheter-to-vessel size facilitates near flow-arrest on catheter insertion, potentially negating the need for a BGC. A 0.088 inch aspiration catheter enables significant flow reversal in the distal MCA during aspiration.

Balloon guide catheter improvements in thrombectomy outcomes persist despite advances in intracranial aspiration technology

BACKGROUND

First-pass effect (FPE) has been established as a key metric for technical success and strongly correlates with better clinical outcomes. Most data supporting improved outcomes with the use of a balloon guide catheter (BGC) predate the advent of last-generation large-bore intracranial aspiration catheters. We aim to evaluate the impact of BGC in FPE and clinical outcomes in a large cohort of patients treated with contemporary technology.

METHODS

Patients were recruited from the prospectively ongoing ROSSETTI registry. This registry includes all consecutive patients with anterior circulation large-vessel occlusion (LVO) from 10 comprehensive stroke centers in Spain. Demographic, clinical, angiographic, and clinical outcome data were compared between BGC and non-BGC groups. FPE was defined as the achievement of mTICI2c-3 after a single device pass.

RESULTS

426 patients were included out of which 271 (63.62%) used BCG. BGC-treated patients had higher FPE rate (45.8% vs 27.7%; P<0.001), higher final mTICI ≥2 c recanalization rate (76.8% vs 50.3%, respectively; P<0.001), shorter procedural time [median (IQR), 30 (19-58) vs 43 (33-71) min; P<0.001], higher NIHSS difference from admission to 24 hours [median (IQR), 8 (2-12) vs 3 (0-10); P=0.001], and lower mortality rate (17.6% vs 29.8%, P=0.026) compared with non-BGC patients. BGC use was an independent predictor of FPE (OR 2.197, 95% CI 1.436 to 3.361; P<0.001), and excellent clinical outcome at 3 months (OR 0.34, 95% CI 0.17 to 0.68; P=0.002).

CONCLUSIONS

Our results support the benefit of BGC use on angiographic and clinical outcomes in anterior circulation LVO ischemic stroke remain significant even when considering recent improvements in intracranial aspiration technology.

Predictors and prognoses of Willisian collateral failure during mechanical thrombectomy

During mechanical thrombectomy in the anterior cerebral circulation, thrombus embolization resulting in Willisian collateral failure may lead to critical stroke outcomes due to a shutdown of leptomeningeal collaterals. We hypothesized that the outcomes of dynamic Willisian collateral failure (DWF), induced during mechanical thrombectomy, would be associated with grave outcomes. We evaluated this hypothesis in consecutive patients, between January 2011 and May 2016, who underwent mechanical thrombectomy for anterior circulation occlusions, with an onset-to-puncture of 24 h. Patients with initial Willisian collateral failure (IWF) were identified first, with remaining patients classified into the DWF and Willisian collateral sparing (WCS) groups. Comparative and multivariable analyses were performed to predict grave outcomes (3-month modified Rankin Scale score of 5–6). Among 567 patients, 37 were in the IWF group, 38 in the DWF group, and 492 in the WCS group. Compared to the WCS and DWF groups, the IWF group had a higher baseline National Institute of Health Stroke Scale score and lower Alberta Stroke Program Early CT Score. The prevalence of grave outcomes was similarly high in the IWF (48.6%) and DWF (47.4%) groups, but lower in the WCS group (22.0%; p < 0.001). IWF and DWF were independent risk factors for a grave outcome.

Balloon Guide Catheter is Not Superior to Conventional Guide Catheter when Stent Retriever and Contact Aspiration are Combined for Stroke Treatment

BACKGROUND

The effectiveness of balloon guide catheter (BGC) use has not been prospectively studied and its added value for improving reperfusion in acute ischemic stroke (AIS) treatment has only been reported in studies in which no contact aspiration was combined with the stent retriever (CA + SR).

OBJECTIVE

To compare the reperfusion results and clinical outcomes with and without BGC use when a combined CA + SR strategy is employed in first line to treat AIS.

METHODS

From January 2016 to April 2019, data from the ETIS registry (Endovascular Treatment in Ischemic Stroke) were reviewed. We included patients having undergone endovascular treatment with a combined CA + SR strategy and use or not of a BGC according to the operator's discretion. We compared BGC and nonBGC populations with matching and inverse probability of treatment weighting propensity scores. Primary outcome was the final near-complete/complete revascularization (mTICI2c/3) rate. Secondary outcomes included clinical outcomes and safety considerations.

RESULTS

Among 607 included patients, BGC was used in 32.9% (n = 200), and 190 matched pairs could be found. We found no significant difference in final mTICI2c/3 between patients with and without BGC (60.1% in BGC group compared to 62.7% in nonBGC group (matched RR, 0.92; 95%CI, 0.80 to 1.14)), first-pass mTICI2c/3 (35.1% vs 37.3%, matched RR, 0.94; 95%CI, 0.68 to 1.30), clinical outcome (matched RR of 1.12 (95%CI, 0.85 to 1.47) for favorable outcome.

CONCLUSION

The reperfusion and clinical results with and without BGC use are not significantly different when combined CA + SR are used as a first-line strategy for large vessel occlusion in the setting of AIS.

Comparison of FlowGate2 and Merci as balloon guide catheters used in mechanical thrombectomies for stroke intervention

The present study reports on the usefulness of FlowGate² (FG2) as a novel balloon guide catheter (BGC) for mechanical thrombectomy (MT) treatment. MT using a BGC device was performed on 255 patients at the authors' institution (St. Vincent's hospital, Suwon, Korea and Hangang Sacred Heart Hospital, Seoul, Korea) between January 2014 and September 2018. A total of 235 patients underwent successful application of BGCs and were divided into two groups; an FG2 and a Merci group, and a comparative analysis was performed. The failure rate in the FG2 group (2.5%) was significantly lower than that in the Merci group (10.8%; P=0.016). Occurrence of distal emboli was significantly lower in the FG2 group (4.7%) than in the Merci group (7.3%; P=0.012). According to subgroup analysis of the BGC and the intermediate catheter, the incidence rate of the distal emboli in the FG2 with an intermediate catheter (2.3%) was significantly lower than that of the Merci with an intermediate catheter (6.6%; P=0.038). The ratio of thrombolysis in cerebral infarction (TICI) 3 recanalization in the first pass was higher in the FG2 group than in the Merci group, in both total (44.7 vs. 34.7%; P=0.033) and subgroup patients (46.5 vs. 34.4%; P=0.029). In the multivariate analysis, use of an intermediate catheter [odds ratio (OR), 0.75; 95% confidence interval (CI), 0.66-0.94; P=0.029] and FG2 application (OR, 0.59; 95% CI, 0.25-0.93; P=0.020) were the predictive factors for fewer distal emboli. In summary, FG2 BGC enables an effective MT with less application failures and occurrence of distal emboli, and higher TICI 3 recanalization at the first stent passage, compared with Merci BGC.

Safety and efficacy of the SeparGate™ balloon-guiding catheter in neurointerventional surgery: Study protocol of a prospective multicenter single-arm clinical trial

Background

The balloon-guiding catheter (BGC) reportedly reduces the number of retrievals and occurrence of distal emboli, achieving superior revascularization results and improved clinical outcomes in acute stroke. This study will aim to examine the efficacy and safety of the new SeparGate™ BGC.

Design

This prospective multicenter single-arm clinical trial will aim to include 128 patients who fulfill its inclusion and exclusion criteria. All patients will receive endovascular interventional therapy with BGC assistance. The primary endpoint will be the immediate surgical success rate, while the secondary endpoint will be product performance. The safety evaluation will include serious adverse events such as puncture site hematoma and bleeding, cerebral vasospasm, vessel dissection, vessel perforation, air embolism, thrombus (acute or subacute), vessel occlusion, distal embolization, infection, adverse reaction to antiplatelet and anticoagulant drugs, intracranial hemorrhage, stroke, death, and device defect.

Discussion

The prospective multicenter trial will provide safety and efficacy information for the SeparGate™ BGC. Its findings will provide a clinical reference for endovascular adjuvant therapy of cerebrovascular disease.

Trial registration

ChiCTR1800014459.

Role of Balloon Guide Catheter in Modern Endovascular Thrombectomy

Proximal flow control achieved with a balloon guide catheter (BGC) during endovascular treatment of acute ischemic stroke is reviewed in this article. In clinical practice, BGCs offer a multi-faceted approach for clot retrieval by creating proximal flow arrest, reducing embolic burden, and shortening procedure time. Evaluation of frontline thrombectomy procedures with BGCs revealed advantages of combined use over the conventional guide catheter (CGC), notably in the significant reduction of distal emboli to both the affected and previously unaffected territories. Recently, new measures of early and complete reperfusion at first thrombectomy pass have been identified as independent predictors of improved outcomes, which were consistently demonstrated with use of BGC as a safe and effective option to minimize number of passes during intervention. Prior randomized controlled trials reported the positive correlation between BGC-treated patients and a lower risk of mortality as well as shortened procedure time. While BGC use is more common in stent retriever-mediated mechanical thrombectomy, preliminary data has shown the potential benefit of device application during contact aspiration thrombectomy to achieve successful recanalization. However, the question of which major endovascular strategy reigns superior as a frontline remains to be answered. Along with clinical case assessments, BGC performance during in-vitro simulation was analyzed to further understand mechanisms for optimization of thrombectomy technique.

Preprocedure Intravenous Recombinant Tissue Plasminogen Activator and Risk of Distal Embolization with Thrombectomy in Acute Ischemic Stroke

BACKGROUND

Intravenous recombinant tissue plasminogen activator (IV rt-PA) prior to thrombectomy may reduce the risk of intraprocedural distal embolization in acute ischemic stroke patients.

METHODS

We analyzed the diffusion-weighted imaging acquired with 1.5- or 3-T magnetic resonance imaging (MRI) scans obtained within 24 hours of thrombectomy in consecutive acute ischemic stroke patients. An independent physician identified distal embolization, defined as discrete foci of restricted diffusion independent of the primary area of infarction on MRI scan. Patients were stratified based on whether they had or did not receive IV rt-PA prior to thrombectomy.

RESULTS

Distal embolization was seen in 59 (ipsilateral in 56) of 63 patients (mean age ± SD; 64.6 ± 15.3 years) who underwent thrombectomy (mean number 8.6; range 0-32). There was no difference in mean number of ipsilateral hemispheric distal embolization between the 2 groups (7.9 ± 6.1 versus 7.5 ± 7.6, P = .82). After adjusting for age, admission National Institutes of Health Stroke Scale score, the time interval between symptom onset and thrombectomy, there was no association between receiving IV rt-PA prior to thrombectomy and number of ipsilateral distal emboli (P = .90). There was no relationship between the number of ipsilateral emboli and rates of favorable outcome after adjusting for other confounders (adjusted odds ratio 1.0; 95% confidence interval .89 - 1.0; P = .40).

CONCLUSIONS

Although distal embolization is very common after thrombectomy, IV rt-PA prior to procedure does not reduce the risk of intraprocedural distal embolization.

Predictors of Balloon Guide Catheter Assistance Success in Stent-retrieval Thrombectomy for an Anterior Circulation Acute Ischemic Stroke

Introduction Mechanical thrombectomy has become the standard treatment for large vessel occlusion (LVO) in acute ischemic stroke (AIS) in well-selected patients. Although many devices and strategies exist, the use of a balloon-tip guide catheter (BGC) with stent-retriever (SR) may hold several advantages. We aim to assess the efficacy and identify predictors of technical success of this unique approach. Methods From our prospectively maintained database, we identified consecutive cases in which a BGC was used for stent-retriever thrombectomy in anterior circulation LVO between 2015 and 2016. Baseline and procedural characteristics were captured and analyzed. Predictors of technical and clinical outcomes were identified by multivariable logistic regression analysis. Results Ninety-three patients with AIS-LVO were treated with BGC-assisted mechanical thrombectomy. The mean age was 71 years old (SD 14), with 49.5% male (n=46). Pre-operative IV-tPA was administered in 55.9% (n=52) of cases. The most common location of occlusive thrombus was M1 (64.5%, n=60). Successful recanalization (mTICI=2b-3) was achieved in 86.0% (n=80) of cases while complete revascularization (mTICI-3) was achieved in 56.5% (n=52). There was a first-pass success rate of 52.7% (n=49). At discharge, 38.7% of the patients were functionally independent (mRS≤2). Multivariate analysis revealed that the middle cerebral artery location was strongly predictive of first-pass success, resulting in mTICI =2b revascularization (OR 7.10, p=0.018). Additionally, female gender (OR 2.85, p=0.042) and decreasing mTICI were associated with a poor clinical outcome (mRS≥4; OR 1.76, p=0.008). Conclusions BGC assistance in stent retrieval thrombectomy is safe and effective for AIS due to anterior circulation LVO. Further investigation is required to elucidate the optimal treatment strategy based on patient and disease characteristics.

ANCD thrombectomy device: in vitro evaluation

Introduction

Endovascular treatment of stroke, although highly effective, may fail to reach complete recanalization in around 20% of cases. The Advanced Thrombectomy System (ANCD) is a novel stroke thrombectomy device designed to reduce clot fragmentation and facilitate retrieval by inducing local flow arrest and allowing distal aspiration in combination with a stent retriever. We aimed to assess the preclinical efficacy of ANCD.

Methods

Soft red blood cell (RBC)-rich (n=20/group) and sticky fibrin-rich (n=30/group) clots were used to create middle cerebral artery (MCA) occlusions in two vascular phantoms. Three different treatment strategies were tested: (1) balloon guide catheter + Solitaire (BGC+SR); (2) distal access catheter + SR (DAC+SR); and (3) ANCD+SR, until complete recanalization was achieved or to a maximum of three passes. The recanalization rate was determined after each pass.

Results

After one pass, ANCD+SR resulted in an increased recanalization rate (94%) for all clots together compared with BGC+SR (66%; p<0.01) or DAC+SR (80%; p=0.04). After the final pass the recanalization rate increased in all three groups but remained higher with ANCD+SR (100%) than with BGC+SR (74%; p<0.01) or DAC+SR (90%; p=0.02). The mean number of passes was lower with ANCD+SR (1.06) than with BGC+SR (1.46) or DAC+SR (1.25) (p=0.01). A logistic regression model adjusted for treatment arm, clot type, and model used showed that both RBC-rich clots (OR 8.1, 95% CI 1.6 to 13.5) and ANCD+SR (OR 3.9, 95% CI 1.01 to 15.8) were independent predictors of first-pass recanalization.

Conclusion

In in vitro three-dimensional models replicating MCA-M1 occlusion, ANCD+SR showed significantly better recanalization rates in fewer passes than other commonly used combinations of devices.

The Effects of Balloon-Guide Catheters on Outcomes after Mechanical Thrombectomy in Acute Ischemic Strokes : A Meta-Analysis

Objective

Mechanical thrombectomies with balloon-guide catheters (BGC) are thought to improve successful recanalization rates and to decrease the incidence of distal emboli compared to thrombectomies without BGC. We aimed to assess the effects of BGC on the outcomes of mechanical thrombectomy in acute ischemic strokes.

Methods

Studies from PubMed, EMBASE, and the Cochrane library database from January 2010 to February 2018 were reviewed. Random effect model for meta-analysis was used. Analyses such as meta-regression and the “trim-and-fill” method were additionally carried out.

Results

A total of seven articles involving 2223 patients were analyzed. Mechanical thrombectomy with BGC was associated with higher rates of successful recanalization (odds ratio [OR], 1.632; 95% confidence interval [CI], 1.293–2.059). BGC did not significantly decrease distal emboli, both before (OR, 0.404; 95% CI, 0.108–1.505) and after correcting for bias (adjusted OR, 1.165; 95% CI, 0.310–4.382). Good outcomes were observed more frequently in the BGC group (OR, 1.886; 95% CI, 1.564–2.273). Symptomatic intracranial hemorrhage and mortality did not differ significantly with BGC use.

Conclusion

Our meta-analysis demonstrates that BGC enhance recanalization rates. However, BGC use did not decrease distal emboli after mechanical thrombectomies. This should be interpreted with caution due to possible publication bias and heterogeneity. Additional meta-analyses based on individual patient data are needed to clarify the role of BGC in mechanical thrombectomies.

Endovascular recanalization for symptomatic subacute and chronic intracranial large artery occlusion of the anterior circulation: initial experience and technical considerations

PURPOSE

This study aimed to report the clinical findings and initial clinical experience of endovascular recanalization for symptomatic subacute/chronic intracranial large artery occlusion (ILAO) of the anterior circulation.

METHODS

From October 2015 to December 2017, 13 patients with symptomatic subacute/chronic ILAO of the anterior circulation were enrolled in this study and underwent endovascular recanalization. We collected the initial procedural results, including the rate of successful recanalization and periprocedural complications, and data pertaining to angiographic and clinical follow-up.

RESULTS

Recanalization was successful in 11 of 13 patients (84.6%). Intraoperative complications occurred in four cases, including symptomatic distal embolism in three cases; one of which was simultaneously complicated with artery dissection. Intracerebral hemorrhage occurred in one case. Eleven patients underwent angiographic follow-up, and 12 patients underwent clinical follow-up. The results of the angiography follow-up (mean 6 ± 3.29 months) showed that in-stent restenosis occurred in one of the 11 successfully recanalized patients. However, the artery was occluded again in the patient who achieved thrombolysis in cerebral infarction (TICI) grade of 2a after treatment. Clinical follow-up (mean 5.8 ± 2.25 months) showed no recurrence of transient ischemic attack (TIA) or stroke in ten successfully recanalized cases. However, the patient who developed in-stent stenosis suffered TIA.

CONCLUSIONS

Endovascular recanalization for symptomatic subacute/chronic ILAO of anterior circulation is feasible, relatively safe, and efficacious in highly selected cases, improving patients' symptoms in the short-term. However, further larger scale pilot studies are needed to determine the efficacy and long-term outcome associated with this treatment.

Experience of the New FlowGate2 Device as a Balloon Guide Catheter for Ischemic Stroke Intervention

BACKGROUND

We report the experience of the FlowGate² (FG2) as a new balloon guide catheter in endovascular stroke intervention.

METHODS

We evaluated the various outcomes and complications of patients with intracranial large artery occlusion undergoing endovascular stroke intervention with FG2 at our center. Baseline characteristics (failure rate of device application, sex, age, risk factors, arterial occlusion sites, and time intervals) were reviewed. Outcomes were evaluated according to National Institutes of Health Stroke Scale score, modified Rankin Scale (mRS) score, number of stent passages required, and Thrombolysis in Cerebral Infarction score. The incidence of hemorrhage, vessel damage, distal emboli, and mortality rate were evaluated as indicators of complications.

RESULTS

Overall, 70 patients were enrolled, except the 2 patients with application failure of FG2. Seventy patients with a median age of 69 years were treated with FG2. Arterial occlusion involved the M1 (50%) and M2 (14.3%) segments, internal carotid artery (25.7%), and posterior circulation (10%). Median value of mRS at 90 days was 2.8, and 37 patients (52.8%) had a mRS score ≤2. The recanalization rate in patients with a Thrombolysis in Cerebral Infarction score of 2b or 3 was 91.4%. The hemorrhage rate was 5.7%, but none were symptomatic. In terms of complications, distal emboli occurred in 4.3% of cases.

CONCLUSIONS

Endovascular stroke intervention with the FG2 is safe and effective with good accessibility and less occurrence of distal emboli. Its trackability, stability, and luminal size make the FG2 suitable for stroke intervention.