Effect of balloon guide catheter utilization on contact aspiration thrombectomy

Comparison of Clinical and Radiological Outcomes Between Different (Balloon) Guide Catheter With and Without Inflated Balloon in Acute Ischemic Stroke Patients: A MaSQ-Registry Study

PURPOSE

Balloon guide catheters (BGCs) are used in endovascular treatment (EVT) for ischemic stroke. Previous literature did not distinguish between BGC use with and without inflated balloon. This study aims to compare outcomes between non-BCG and BGC use with and without inflated balloon during EVT.

METHODS

Patients who underwent EVT for anterior circulation ischemic stroke between September 2020 and February 2023 were analyzed. Patients were divided into three groups: non-BGC, BGC with inflated balloon, or BGC without inflated balloon. The primary outcome was the ordinal modified Rankin Scale (mRS) at 90-day follow-up. Secondary outcomes included expanded Thrombolysis In Cerebral Ischemia score (eTICI) and periprocedural complications. Regression analyses with BGC with inflated balloon as comparator were performed with adjustments. Subgroup analyses were conducted based on first-line thrombectomy technique.

RESULTS

Out of 511 patients, 428 patients were included. Compared to BCG with inflated balloon, the mRS at 90 days did not differ in the group without inflated balloon (adjusted common [ac]OR: 1.07, 95%CI 0.67-1.73) or non-BGC (acOR: 1.42, 95%CI 0.83-2.42). Compared to patients treated with a BGC with inflated balloon, those treated with BGC without inflated balloon had lower eTICI scores (acOR: 0.59, 95%CI 0.37-0.94), and patients treated with non-BGC had lower chances of periprocedural complications (aOR: 0.41, 95%CI 0.20-0.86).

CONCLUSIONS

This study shows no clinical differences in ischemic stroke patients treated with BGC with inflated balloon compared to non-BGC and BGC without inflated balloon, despite lower periprocedural complication rates in the non-BGC group and lower eTICI scores in the BGC without inflated balloon group.

LEVEL OF EVIDENCE

Level 3, non-controlled retrospective cohort study.

Current Approaches and Methods to Understand Acute Ischemic Stroke Treatment Using Aspiration Thrombectomy

Acute ischemic stroke occurs when a blood clot occludes a cerebral artery. Mechanical interventions, primarily stent retrievers and aspiration thrombectomy, are used currently for removing the occluding clot and restoring blood flow. Aspiration involves using a long catheter to traverse the cerebral vasculature to reach the blood clot, followed by application of suction through the catheter bore. Aspiration is also used in conjunction with other techniques such as stent retrievers and balloon guide catheters. Despite the wide use of aspiration, our physical understanding of the process and the causes of the failure of aspiration to retrieve cerebral clots in certain scenarios is not well understood. Experimental and computational studies can help develop the capability to provide deeper insights into the procedure and enable development of new devices and more effective treatment methods. We recapitulate the aspiration-based thrombectomy techniques in clinical practice and provide a perspective of existing engineering methods for aspiration. We articulate the current knowledge gap in the understanding of aspiration and highlight possible directions for future engineering studies to bridge this gap, help clinical translation of engineering studies, and develop new patient-specific stroke therapy.

Matched-pair analysis of patients with ischemic stroke undergoing thrombectomy using next-generation balloon guide catheters

BACKGROUND

Balloon guide catheters (BGCs) have not been widely adopted, possibly due to the incompatibility of past-generation BGCs with large-bore intermediate catheters. The next-generation BGC is compatible with large-bore catheters. We compared outcomes of thrombectomy cases using BGCs versus conventional guide catheters.

METHODS

We conducted a retrospective study of 110 thrombectomy cases using BGCs (n=55) and non-BGCs (n=55). Sixty consecutive thrombectomy cases in whom the BOBBY BGC was used at a single institution between February 2021 and March 2022 were identified. Of these, 55 BGC cases were 1:1 matched with non-BGC cases by proceduralists, age, gender, stent retriever + aspiration device versus aspiration-only, and site of occlusion. First-pass effect was defined as Thrombolysis In Cerebral Infarction 2b or higher with a single pass.

RESULTS

The BGC and non-BGC cohorts had similar mean age (67.2 vs 68.9 years), gender distribution (43.6% vs 47.3% women), median initial National Institutes of Health Stroke Scale score (14 vs 15), and median pretreatment ischemic core volumes (12 mL vs 11.5 mL). BGC and non-BGC cases had similar rates of single pass (60.0% vs 54.6%), first-pass effect (58.2% vs 49.1%), and complications (1.8% vs 9.1%). In aspiration-only cases, the BGC cohort had a significantly higher rate of first-pass effect (100% vs 50.0%, p=0.01). BGC was associated with a higher likelihood of achieving a modified Rankin Scale score of 2 at discharge (OR 7.76, p=0.02). No additional procedural time was required for BGC cases (46.7 vs 48.2 min).

CONCLUSION

BGCs may be safely adopted with comparable procedural efficacy, benefits to aspiration-only techniques, and earlier functional improvement compared with conventional guide catheters.

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.

Predictors of Angiographic Outcome After Failed Thrombectomy for Large Vessel Occlusion: Insights from the Stroke Thrombectomy and Aneurysm Registry

BACKGROUND

Mechanical thrombectomy failure (MTF) occurs in approximately 15% of cases.

OBJECTIVE

To investigate factors that predict MTF.

METHODS

This was a retrospective review of prospectively collected data from the Stroke Thrombectomy and Aneurysm Registry. Patients who underwent mechanical thrombectomy (MT) for large vessel occlusion (LVO) were included. Patients were categorized by mechanical thrombectomy success (MTS) (≥mTICI 2b) or MTF (

RESULTS

A total of 6780 patients were included, and 1001 experienced anterior circulation MTF. Patients in the MTF group were older (73 vs 72, P = .044) and had higher poor premorbid modified Rankin Scale (mRS) (10.8% vs 8.4%, P = .017). Onset to puncture time was greater in the MTF group (273 vs 260 min, P = .08). No significant differences were found between the access site, use of balloon guide catheter, frontline technique, or first-pass devices between the MTF and MTS groups. More complications occurred in the MTF group (14% vs 5.8%), including symptomatic intracerebral hemorrhage (9.4% vs 6.1%) and craniectomies (10% vs 2.8%) ( P < .001). On UVA, age, poor pretreatment mRS, increased number of passes, and increased procedure time were associated with MTF. Internal carotid artery, M1, and M2 occlusions had decreased odds of MTF. Poor preprocedure mRS, number of passes, and procedure time remained significant on MVA. A subgroup analysis of posterior circulation LVO revealed that number of passes and total procedure time correlated with increased odds of MTF ( P < .001) while rescue stenting was associated with less odds of MTF (odds ratio 0.20, 95% CI 0.06-0.63). Number of passes remained significant on MVA of posterior circulation occlusion subgroup analysis.

CONCLUSION

Anterior circulation MTF is associated with more complications and worse outcomes. No differences were found between techniques or devises used for the first pass during MT. Rescue intracranial stenting may decrease the likelihood of MTF for posterior circulation MT.

Collapse

Key Words Collapse

MESH Headings

• Humans
• Stroke/surgery
• Thrombectomy/methods
• Cerebral Hemorrhage
• Retrospective Studies
• Aneurysm
• Registries
• Treatment Outcome
• Brain Ischemia/therapy

Collapse

Grants Collapse

Affiliation(s)

Matthew Webb Department of Neurosurgery, University of Texas Health Science Center San Antonio, San Antonio , Texas , USA
Muhammed Amir Essibayi Medical University of South Carolina, Charleston , South Carolina , USA
Sami Al Kasab Medical University of South Carolina, Charleston , South Carolina , USA
Ilko L Maier University Medical Center Göttingen, Göttingen , Germany
Marios-Nikos Psychogios University Hospital Basel, Basel , Switzerland
Jonathan A Grossberg Emory University, Atlanta , Georgia , USA
Ali Alawieh Emory University, Atlanta , Georgia , USA
Stacey Quintero Wolfe Wake Forest University, Winston-Salem , North Carolina , USA
Adam Arthur University of Tennessee Health Science Center, Memphis , Tennessee , USA
Travis Dumont Bannner University of Arizona Medical Center, Tucson , Arizona , USA
Peter Kan University of Texas Medical Branch, Galveston , Texas , USA
Joon-Tae Kim Chonnam National University Hospital, Gwangju , South Korea
Reade De Leacy Mount Sinai Health System, New York , New York , USA
Joshua Osbun Washington University in St. Louis, St. Louis , Missouri , USA
Ansaar Rai Department of Neuroradiology, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
Pascal Jabbour Department of Neuroradiology, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
Min S Park Thomas Jefferson University Hospital, Philadelphia , Pennsylvania , USA
Roberto Crosa University of Virginia, Charlottesville , Virginia , USA
Michael R Levitt Centro Endovascular Neurológico, Médica Uruguaya, Montevideo , Uruguay
Adam Polifka University of Washington, Seattle , Washington , USA
Shinichi Yoshimura University of Florida, Gainesville , Florida , USA
Charles Matouk Hyogo College of Medicine, Nishinomiya , Japan
Richard W Williamson Yale School of Medicine, New Haven , Connecticut , USA
Isabel Fragata Allegheny General Hospital, Pittsburgh , Pennsylvania , USA
Shakeel A Chowdhry Centro Hospitalar Universitário de Lisboa Central, Lisboa , Portugal
Robert M Starke NorthShore University Health System, Evanston , Illinois , USA
Edgar A Samaniego University of Miami Health System, Miami , Florida , USA
Hugo Cuellar University of Iowa, Iowa City , Iowa , USA
Alejandro Spiotta Medical University of South Carolina, Charleston , South Carolina , USA
Justin Mascitelli Department of Neurosurgery, University of Texas Health Science Center San Antonio, San Antonio , Texas , USA

Collapse

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.

Effect of proximal blood flow arrest during endovascular thrombectomy (ProFATE): Study protocol for a multicentre randomised controlled trial

BACKGROUND

Observational studies have demonstrated improved outcomes with the adjunctive use of balloon guide catheters (BGC) during endovascular thrombectomy (EVT) for anterior circulation acute ischaemic stroke (AIS). However, the lack of high-level evidence and global practice heterogeneity justifies a randomised controlled trial (RCT) to investigate the effect of transient proximal blood flow arrest on the procedural and clinical outcomes of patients with AIS following EVT.

HYPOTHESIS

Proximal blood flow arrest in the cervical internal carotid artery during EVT for proximal large vessel occlusion is superior to no flow arrest in achieving complete vessel recanalisation.

METHODS

ProFATE is an investigator-initiated, pragmatic, multicentre RCT with blinding of participants and outcome assessment. An estimated 124 participants with an anterior circulation AIS due to large vessel occlusion, an NIHSS of ⩾2, ASPECTS ⩾ 5 and eligible for EVT using a first-line combined technique (contact aspiration and stent retriever) or contact aspiration only will be randomised (1:1) to receive BGC balloon inflation or no inflation during EVT.

OUTCOMES

The primary outcome is the proportion of patients achieving near-complete/complete vessel recanalisation (eTICI 2c-3) at the end of the EVT procedure. Secondary outcomes include the functional outcome (modified Rankin Scale at 90 days), new or distal vascular territory clot embolisation rate, near-complete/complete recanalisation after the first pass, symptomatic intracranial haemorrhage, procedure-related complications and death at 90 days.

DISCUSSION

This is the first RCT to investigate the effect of proximal blood flow arrest during EVT using a BGC on the procedural and clinical outcomes of patients with AIS due to large vessel occlusion.

Undeflatable balloon guide catheter (BGC) during endovascular procedure: Rescue strategy

The use of a balloon guide catheter (BGC) in the endovascular management of acute ischemic stroke is known to improve the efficacy and efficiency of the procedure by reducing the risk of distal embolization. During the procedure, the balloon of the catheter causes a temporary arrest of cerebral blood flow. However, failure of the balloon to deflate during the BGC procedure can result in catastrophic complications, including aggravated hypoxic damage.<br/> This paper aims to share the resolution and methodological analysis of our experience with BGC balloon deflation failure, which was confirmed by a reproducible experiment under similar conditions.

REACT Aspiration Catheters: Clinical Experience and Technical Considerations

Aspiration catheters are widely used in mechanical thrombectomy procedures to treat acute ischemic stroke due to large vessel occlusion. The key performance requirements for aspiration catheters are ease of navigation and effective aspiration. In this work, we review the clinical experience and in vitro studies of REACT aspiration catheters (Medtronic, Minneapolis, MN, USA). In vitro experiments showed that REACT catheters exhibit solid performance in navigation and aspiration. Previous studies reported that the recanalization capacity of the aspiration catheters can be influenced by the devices’ inner diameter and tip distensibility, the catheter-to-vessel diameter ratio, the negative pressure delivered by the vacuum generator, the cyclical aspiration mode, the proximal flow arrest, and the angle of interaction between catheter and clot. REACT catheters can be navigated through the vasculature without any support from a microcatheter/ microwire in favorable anatomical configurations. In challenging situations, mostly encountered when crossing the ophthalmic segment of the internal carotid artery, the use of the stentriever anchoring technique or delivery assist catheter can facilitate the navigation. Three clinical studies reporting on 299 patients who underwent mechanical thrombectomy with REACT catheters were included in this review. Successful recanalization (modified treatment in cerebral ischemia score 2b–3) was achieved in 89–96% of cases, no procedural complications related to REACT catheters were reported, and functional independence (modified Rankin Scale 0–2) at 90-days was 24–36%. In vitro experimental evaluations and clinical studies support the safety and effectiveness of the REACT catheters.

The Q and A-The MIVI Q Catheters for Aspiration Thrombectomy-Initial Experience from London

Background: Aspiration thrombectomy is a widely accepted treatment option for large vessel occlusion (LVO). The MIVI aspiration system has a novel design to maximize the lumen size. We present the results of our initial experience with this innovative aspiration thrombectomy system. Materials and Methods: Retrospectively, we reviewed our database to find all cases of LVO treated with the MIVI Q system (February 2019 and July 2020). In addition, we recorded the baseline demographics, NIHSS, ASPECT, mTICI scores, procedural time, complications, and 90 day mRS. Results: Herein, we identified 25 patients with an average age of 65.3 ± 19.3 years (range 19–89), majority of whom were female (n = 14, 56%). The average NIHSS was 16.9 ± 6.7 (range 6–30), and the average CT ASPECT was 7.9 ± 1.4 (range 5–10). The most common clot location was the M1 segment of the MCA (n = 16, 64%). Four of the patients had tandem lesions (16%). The average clot length was 21.7 ± 31 mm (range 2–130 mm). Of the 23 cases where the Q catheter reached the proximal clot face, mTICI ≥ 2b was achieved on the first pass in 11 cases (44%), and at the end of the ‘Q aspiration’ only the procedures with 16 patients achieved mTICI ≥ 2b recanalization (64%). Stent-retrievers were used in 13 cases (52%). At the end of the procedure, 24 patients (96%) achieved mTICI ≥ 2b with 18 patients (72%) achieving mTICI ≥ 2c. The average number of passes with the Q catheter, including when it was used for SOLUMBRA, was 2.1 ± 2.2 (range 1–10). The mean procedure time was 69 ± 32 mins (range 7–116 mins). No complications were associated with the MIVI Q. Conclusions: The MIVI aspiration system is a novel technology with regards to aspiration mechanical thrombectomy. The system is easy to use with early results comparable to other large-bore catheter systems. However, further studies are needed.

Endovascular Treatment for Acute Basilar Artery Occlusion: A Comparison of Arteriosclerotic, Embolic and Tandem Lesions

PURPOSE

To evaluate the safety and efficacy of endovascular treatment (EVT) for patients with acute ischemic stroke (AIS) due to intracranial atherosclerosis-related basilar artery occlusion (ICAS-related BAO) by comparison with embolic and tandem occlusion.

METHODS

We retrospectively reviewed consecutive patients with AIS due to BAO who underwent EVT. Patients were assigned to the ICAS-related group and embolic group, and tandem group based on the etiology. Baseline data, procedural details, and clinical outcomes were compared between the three groups.

RESULTS

A total of 100 patients (ICAS-related group: 31; embolic group: 41; tandem group: 28) were included. No significant difference was observed in the successful reperfusion (mTICI 2b or 3), but the procedural time differed significantly (60 min vs. 43 min vs. 60 min, P = 0.010). There were no differences in the different intracranial hemorrhage grades among the three groups (P = 0.134). After adjusting for baseline differences, there was no significant difference in pairwise comparisons regarding favorable outcome (mRS 0-2), moderate outcome (mRS 0-3), and mortality.

CONCLUSIONS

Endovascular treatment for patients with acute ICAS-related BAO had equal efficacy and safety compared with embolic BAO and tandem BAO. Primary endovascular treatment and rescue modalities were effective treatments for acute ICAS-related BAO.

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.

Balloon guide catheters: use, reject, or randomize?

Thrombectomy devices played an important role in the success of endovascular treatment trials over the past five years. A balloon guide catheter (BGC) is an adjunctive device used to arrest and reverse flow by inflating the balloon at its tip, which allows for flow reversal in intracranial arteries during retrieval of thrombectomy devices by applying concomitant aspiration through its lumen. Thereby, it can decrease the risk of clot fragmentation and distal embolization. Despite the numerous benchtop and clinical observational studies showing the superiority of BGC to conventional guide catheters in improving reperfusion quality and clinical outcome, its use is still low in clinical practice. The reasons behind this reluctance might be related to technical and cost issues. Therefore, high level evidence data, i.e., a randomized clinical trial, are needed to increase its implementation in thrombectomy procedures. Nonetheless, several obstacles and challenges can prevent the completion of such a trial, and efforts are needed to overcome them. We provide an overview of the current opinions about BGCs in the neurointerventional community and discuss the feasibility and challenges of a possible randomized trial to answer the question "should a BGC be routinely used in endovascular treatment of acute ischemic stroke?"

Effect of distal access catheter tip position on angiographic and clinical outcomes following thrombectomy using the combined stent-retriever and aspiration approach

Purpose

Mechanical thrombectomy using the stent-retriever in conjunction with the distal access catheter may improve the rates of successful revascularization and clinical outcomes in patients with acute stroke. We aimed to compare two different thrombectomy techniques, according to the position of the distal access catheter tip in the combined stent-retriever and aspiration approach.

Methods

In this retrospective study, patients with middle cerebral artery occlusion treated with the combined technique were divided into two groups based on the tip position of the distal access catheter: distal group (catheter placed adjacent to the thrombus) and proximal group (catheter placed in the cavernous segment of the internal carotid artery below the ophthalmic artery). Baseline characteristics, angiographic results, and clinical outcomes were compared.

Results

Eighty-three patients (distal group, n = 45; proximal group, n = 38) were included. Higher complete reperfusion was observed in the distal group (unweighted analysis: 66.7% vs. 42.1%, p = 0.025; weighted analysis: 74.0% vs. 28.8%; p = 0.002). In the multivariate analysis, the distal tip position was independently associated with complete reperfusion (unweighted analysis: aOR, 4.10; 95% CI, 1.40–11.98; p = 0.01; weighted analysis: aOR, 5.20; 95% CI, 1.72–15.78; p = 0.004). The distal group also showed more favorable clinical outcomes and early neurological improvement (unweighted analysis: 62.2% vs. 55.3%; p = 0.521, 60% vs. 50%; p = 0.361, respectively; weighted analysis: 62.7% vs. 61.1%; p = 0.877, 66% vs. 45.7%; p = 0.062, respectively). However, more arterial dissections were observed in the distal group (8.9%, n = 4 vs. 2.6%, n = 1; p = 0.36). In the distal group, one patient with vascular injury died due to complications. No cases of emboli in new territory were observed.

Conclusions

Distal tip position of the distal access catheter has a significant impact on reperfusion in patients with acute ischemic stroke. However, there was also a higher rate of vascular injury as the catheter was advanced further. If advancement to the target lesion is too difficult, placing it in the cavernous internal carotid artery may be a viable method without complications.

Usefulness of combination usage of balloon guide catheter with contact aspiration thrombectomy

BACKGROUND

Angiographic outcomes of contact aspiration thrombectomy (CAT), a frontline thrombectomy strategy, can vary depending on balloon guide catheter (BGC) usage, stroke etiology, and occlusion location. The purpose of this study was to analyze conditional outcomes of CAT to determine which result in maximum angiographic benefits.

METHODS

Patients who received CAT for anterior circulation occlusive stroke between January 2017 and December 2018 were included. Angiographic and clinical outcomes were compared relative to BGC use, stroke etiology, and occlusion location. Multivariable analyses for first-pass reperfusion (FPR) and favorable clinical outcome were performed.

RESULTS

Of 160 included patients, the rates of FPR, successful reperfusion after CAT, final successful reperfusion, and favorable clinical outcome were 43.1%, 58.1%, 81.9%, and 60.6%, respectively. BGC use was associated with a higher rate of FPR, successful reperfusion after CAT, a lower rate of distal embolization, and faster reperfusion. Based on subgroup analysis, BGC usage in ICA, MCA M1 occlusion, and cardioembolism were associated with higher FPR, successful reperfusion after CAT, and lower distal embolization. Faster reperfusion was achieved in ICA occlusions and cardioembolisms. BGC usage was an independent predictor of FPR. Favorable clinical outcome was associated with male gender, low initial NIHSS score, fast onset to reperfusion, and FPR.

CONCLUSIONS

In CAT, BGC usage was associated with better angiographic outcomes, including higher FPR, successful reperfusion after CAT, prevention of distal embolization, and faster reperfusion, especially in proximal occlusions and cardioembolisms. These conditions may play a role in maximizing the benefits of CAT.

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.

Clot imaging characteristics predict first pass effect of aspiration-first approach to thrombectomy

BACKGROUND

The value of clot imaging in patients with emergent large vessel occlusion (ELVO) treated with thrombectomy is unknown.

METHODS

We performed retrospective analysis of clot imaging (clot density, perviousness, length, diameter, distance to the internal carotid artery (ICA) terminus and angle of interaction (AOI) between clot and the aspiration catheter) of consecutive cases of middle cerebral artery (MCA) occlusion and its association with first pass effect (FPE, TICI 2c-3 after a first attempt).

RESULTS

Patients (n = 90 total) with FPE had shorter clot length (9.9 ± 4.5 mm vs. 11.7 ± 4.6 mm, P = 0.07), shorter distance from ICA terminus (11.0 ± 7.1 mm vs. 14.7 ± 9.8 mm, P = 0.048), higher perviousness (39.39 ± 29.5 vs 25.43 ± 17.6, P = 0.006) and larger AOI (153.6 ± 17.6 vs 140.3 ± 23.5, P = 0.004) compared to no-FPE patients. In multivariate analysis, distance from ICA terminus to clot ≤13.5 mm (odds ratio (OR) 11.05, 95% confidence interval (CI) 2.65-46.15, P = 0.001), clot length ≤9.9 mm (OR 7.34; 95% CI 1.8-29.96, P = 0.005), perviousness ≥ 19.9 (OR 2.54, 95% CI 0.84-7.6, P = 0.09) and AOI ≥ 137°^ (OR 6.8, 95% CI 1.55-29.8, P = 0.011) were independent predictors of FPE. The optimal cut off derived using Youden's index was 6.5. The area under the curve of a score predictive of FPE success was 0.816 (0.728-0.904, P < 0.001). In a validation cohort (n = 30), sensitivity, specificity, positive and negative predictive value of a score of 6-10 were 72.7%, 73.6%, 61.5% and 82.3%.

CONCLUSIONS

Clot imaging predicts the likelihood of achieving FPE in patients with MCA ELVO treated with the aspiration-first approach.

Catheter tip distensibility substantially influences the aspiration force of thrombectomy devices

BACKGROUND

A direct aspiration first pass thrombectomy (ADAPT) is a fast-growing technique for which a broad catalog of catheters that provide a wide range of aspiration forces can be used. We aimed to characterize different catheters' aspiration performance on stiff clots in an in vitro vascular model. We hypothesized that labeled catheter inner diameter (labeled-ID) is not the only parameter that affects the aspiration force (asp-F) and that thrombus-catheter tip interaction and distensibility also play a major role.

METHODS

We designed an experimental setup consisting of a 3D-printed carotid artery immersed in a water deposit. We measured asp-F and distensibility of catheter tips when performing ADAPT on a stiff clot analog larger than catheter labeled-ID. Correlations between asp-F, catheter ID, and tip distensibility were statistically assessed.

RESULTS

Experimental asp-F and catheter labeled-ID were correlated (r=0.9601; P<0.01). The relative difference between experimental and theoretical asp-F (obtained by the product of the tip's section area by the vacuum pressure) correlated with tip's distensibility (r=0.9050; P<0.01), evidencing that ADAPT performance is highly influenced by catheter tip shape-adaptability to the clot and that the effective ID (eff-ID) may differ from the labeled-ID specified by manufacturers. Eff-ID showed the highest correlation with experimental asp-F (r=0.9944; P<0.01), confirming that eff-ID rather than labeled-ID should be considered to better estimate the device efficiency.

CONCLUSIONS

Catheter tip distensibility can induce a significant impact on ADAPT performance when retrieving a stiff clot larger than the device ID. Our findings might contribute to optimizing thrombectomy strategies and the design of novel aspiration catheters.

Factors Contributing to an Efficacious Endovascular Treatment for Acute Ischemic Stroke in Asian Population

Although randomized control trials about endovascular treatment (EVT) of emergent large vessel occlusion (LVO) have demonstrated the success of mechanical thrombectomy as the choice of treatment, a wide range of caveats remain unaddressed. Asian patients were rarely included in the trials, thereby raising the question of whether the treatment could be generalized. In addition, there remains a concern on the feasibility of the method with respect to its application against intracranial atherosclerosis (ICAS)-related LVO, frequently observed in the Asian population. It is important to include evidence on ICAS LVO from Asian countries in the future for a comprehensive understanding of LVO etiology. Besides the issues with EVT, prognostic concerns in diabetes patients, acute kidney injury following EVT, neuroprotective management against reperfusion injury, and other peri-EVT issues should be considered in clinical practice. In the current article, we present an in-depth review of the literature that revises information pertaining to such concerns.

Etiological Approach to Understanding Recanalization Failure in Intracranial Large Vessel Occlusion and Thrombectomy: Close to Embolism but Distant From Atherosclerosis

Introduction: In patients with intracranial large vessel occlusion (LVO) who undergo endovascular treatment (EVT), recanalization failure may be related to intracranial atherosclerotic stenosis (ICAS). We evaluated whether the risk factors of recanalization failure could possibly be a marker of ICAS among various types of LVO.

Methods: From a multicenter registry, patients with middle cerebral artery M1 segment occlusions who underwent thrombectomy within 24 h were included. Based on the on-procedure and post-procedure angiographic findings, patients were classified into embolic, ICAS-related, tandem occlusion, and recanalization failure groups. Recanalization failure was defined if the occluded vessel could not be recanalized by stent retrieval, contact aspiration, or local lytics treatment. Risk factors, imaging markers, and EVT methods were compared between groups.

Results: Among 326 patients, 214 were classified as embolism, 76 as ICAS, 16 as tandem, and 20 as recanalization failure. The group with recanalization failure showed higher scores on the National Institutes of Health Stroke Scale (NIHSS) (median, 16.0 vs. 14.5 vs. 14.0 vs. 17.0, p = 0.097), frequent atrial fibrillation (59.3 vs. 18.4 vs. 0 vs. 40.0% p < 0.001), and elevation in erythrocyte sedimentation rate (ESR) (14.5 ± 15.7 vs. 15.0 ± 14.1 vs. 21.2 ± 19.5 vs. 36.0 ± 32.9, p < 0.001) among the groups. The rate of computed tomography angiography-based truncal-type occlusion in recanalization failure group was not as high as that in the ICAS group (8.1 vs. 37.5 vs. 0 vs. 16.7%, p < 0.001). Balloon guide catheters (BGC) were less frequently utilized in the recanalization failure group as compared to their use in the other groups (72.0 vs. 72.4 vs. 62.5 vs. 30.0%, p = 0.001). In the multivariable analysis, initial higher NIHSS [odds ratio (OR), 1.11 95% confidence interval (CI), 1.01–1.22 p = 0.027], higher ESR (OR, 1.03 CI, 1.01–1.05 p = 0.006), and non-use of BGCs (OR, 3.41 CI, 1.14–10.17 p = 0.028) were associated with recanalization failure. In M1 occlusions, the predominant mechanism of recanalization failure was presumed to be embolic in 80% and due to ICAS in 20%.

Conclusion: The analysis of recanalization failures does not suggest an underlying predominant ICAS mechanism. Sufficient utilization of thrombectomy devices and procedures may improve the rates of recanalization.

Preliminary experience with 088 large bore intracranial catheters during stroke thrombectomy

BACKGROUND AND PURPOSE

Thromboaspiration technology continues to evolve at an accelerated pace with increasing availability of larger and more navigable devices. Herein, we provide our initial experience with the intracranial navigation of a large-bore (.088" inner diameter) catheters during mechanical thrombectomy (MT).

METHODS

Retrospective review of consecutive large vessel occlusion stroke patients in whom a TracStar™ or Zoom 88™ (Imperative Care, Campbell, CA) large-bore catheters were utilized in MT. The primary outcome was successful reperfusion (eTICI2b-3) at the end of the procedure. Safety measures included procedural complications and rates of symptomatic intracranial hemorrhage.

RESULTS

Five patients (age,∼50-85 years; baseline NIHSS,17-23) were treated. The .088" catheters were used as the primary tool for contact aspiration in two patients (distal basilar artery and proximal MCA occlusions) with complete thrombus ingestion (eTICI3) during the first pass. In two patients, the .088" catheter was used for flow control where it was placed in the distal M1-segment of a patient with M2 occlusion treated with a combination of stent-retriever and .070" aspiration catheter and in the proximal M1 in a patient with distal M1 occlusion treated with .071" aspiration catheter resulting in eTICI3 reperfusion in both cases. In the fifth patient, the .088" catheter was navigated into the cavernous ICA to support .071" aspiration catheter treatment of an M2 occlusion resulting in eTCI2b67 reperfusion. Procedural duration ranged between 14 and 33 minutes. There were no adverse events.

CONCLUSION

Intracranial navigation of .088" large-bore catheters in MT appears technically feasible and safe. Larger prospective studies are warranted.

Comparison of First-Pass Efficacy Among Four Mechanical Thrombectomy Techniques: A Single-Center Experience

BACKGROUND

First-pass efficacy (FPE) is an established marker of technical and clinical efficacy among mechanical thrombectomy (MT) techniques. It is unclear what the optimal approach is in achieving FPE. We present a single-center experience comparing rates of FPE among 2 MT techniques and evaluate the potential predictors of FPE among other outcomes.

METHODS

A single-center retrospective analysis was carried out of patients with consecutive large-vessel occlusion strokes (LVOS) of anterior circulation from September 2015 to April 2019 who underwent MT and for whom data were available on the status of FPE. Four MT techniques were identified: ADAPT (a direct first-pass aspiration), SrADAPT (stent retriever with aspiration), SRBG (stent retriever with balloon guide catheter), and STRAP (stent retriever-aspiration and proximal flow arrest). The primary outcome was FPE and secondary outcomes included the rate of successful reperfusion.

RESULTS

Among 226 patients with LVOS of the anterior circulation who underwent MT, data were available for 164 on FPE for the 4 MT techniques. SRBG was the most prevalent technique. No significant difference was found in rates of FPE among the 4 MT techniques (P = 0.332). No independent predictors of FPE were identified on multivariable analysis. STRAP had the highest rate of successful reperfusion compared with the other techniques (P = 0.049) and was the only independent predictor of that outcome (P = 0.027).

CONCLUSIONS

Among patients with LVOS of the anterior circulation, the rate of FPE did not differ among the 4 MT techniques. There were no predictors of FPE among the studied variables. STRAP was the only predictor of successful reperfusion.

Predictors of Successful First-Pass Thrombectomy with a Balloon Guide Catheter: Results of a Decision Tree Analysis

Complete recanalization after a single retrieval maneuver is an interventional goal in acute ischemic stroke and an independent factor for good clinical outcome. Anatomical biomarkers for predicting clot removal difficulties have not been comprehensively analyzed and await unused. We retrospectively evaluated 200 consecutive patients who suffered acute stroke and occlusion of the anterior circulation and were treated with mechanical thrombectomy through a balloon guide catheter (BGC). The primary objective was to evaluate the influence of carotid tortuosity and BGC positioning on the one-pass Modified Thrombolysis in Cerebral Infarction Scale (mTICI) 3 rate, and secondarily, the influence of communicating arteries on the angiographic results. After the first-pass mTICI 3, recanalization fell from 51 to 13%. The regression models and decision tree (supervised machine learning) results concurred: carotid tortuosity was the main constraint on efficacy, reducing the likelihood of mTICI 3 after one pass to 30%. BGC positioning was relevant only in carotid arteries without elongation: BGCs located in the distal internal carotid artery (ICA) had a 70% probability of complete recanalization after one pass, dropping to 43% if located in the proximal ICA. These findings demonstrate that first-pass mTICI 3 is influenced by anatomical and interventional factors capable of being anticipated, enabling the BGC technique to be adapted to patient’s anatomy to enhance effectivity.

Distal transradial access in the anatomical snuffbox for balloon guide-assisted stentriever mechanical thrombectomy: Technical note and case report

Recent trends in neuroendovascular surgery have seen a rise in alternative access utilization. Social media feeds such as #RadialFirst or #RadialForNeuro are the beacons of a growing movement among more and more endovascular neurosurgeons, as they venture away from the traditional femoral access gravitating toward radial access. We have previously shown our distal radial access technique utilizing the snuffbox to be a reliable means of endovascular access and in addition to traditional ventral radial access provides access to the entire cerebrum. Stroke thrombectomy often encounters reticence from those who prefer transfemoral access over the radial access. Thrombectomy has been performed radially in a few series and only once previously in a case report of distal radial access for thrombectomy. Hesitance to adopt radial access for mechanical thrombectomy is often related to perceived increased access times and a lack of suitable balloon guide catheters for radial techniques. Here, we present one of the first descriptions of a distal transradial access with balloon guide flow arrest for stentriever thrombectomy.

Safety and Efficacy of Intra-arterial Tirofiban Injection During Mechanical Thrombectomy for Large Artery Occlusion

Objective:

The safety and effect of intra-arterial (IA) tirofiban, a glycoprotein IIb/IIIa inhibitor, during the stent retriever mechanical thrombectomy (MT) was investigated.

Methods:

From January 2015 to May 2019, a total of 327 patients underwent mechanical thrombectomy of large artery occlusions (LAO). Patients were classified into two groups: MT with IA tirofiban (MTT) group and MT only (MTO, without IA tirofiban) group. Clinical outcomes, radiological results, and various complications, such as post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding, and hemorrhagic transformation of infarct were evaluated by comparing the MTT group and MTO group. In addition, subgroup analysis was performed for patients who underwent MT with prior intravenous (IV) tissue plasminogen activator (t-PA).

Results:

The MTT group needed a lower mean number of stent passes and showed a re-occlusion rate as compared with the MTO group (P=0.038 and 0.022, respectively). Between the two groups, there were no statistically significant differences in post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding complications, or hemorrhagic transformation of infarct (P = 0.511, 0.397, 0.429, and 0.355, respectively). In the subgroup analysis, similar findings were observed.

Conclusion:

The use of IA tirofiban during MT seems to be safe and potentially more effective than only MT without IA tirofiban, even in patients who used IV t-PA before MT.

Endovascular Treatment of Acute Ischemic Stroke

급성 허혈성 뇌졸중은 심각한 후유증이나 사망에 이르는 가장 큰 원인 질환들 중 하나이다. 제2세대 혈전제거기구가 도입된 이후로 급성 허혈성 뇌졸중에서 혈관 내 재개통 치료는 급속히 발전해 왔고, 최근에는 표준 치료 중의 하나가 되었다. 이 종설에서는 급성 허혈성 뇌졸중에서 혈관 내 치료와 고식적인 치료를 무작위 배정으로 비교한 임상 연구들의 결과를 간략히 기술하고, 새로이 개정된 급성 허혈성 뇌졸중에서의 혈관 내 치료의 적응증과, 현재 혈관내 치료에 쓰이는 기구들과 방법에 대해 알아보고자 한다.

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.

Frontline Contact Aspiration Treatment for Emergent Large Vessel Occlusion: A Review Focused on Practical Techniques

Endovascular thrombectomy (EVT) as the standard care for acute stroke due to large vessel occlusion has recently been validated through several randomized controlled trials (RCTs). Contact aspiration (CA) and stent retriever (SR) are the two major EVT methods currently used. Because the RCTs have mostly evaluated SR devices, there was a demand to test CA in relation to SR as a frontline EVT treatment method. Recently, the Contact Aspiration vs Stent Retriever for Successful Recanalization (ASTER) study, the first RCT to compare CA and SR, demonstrated similar efficacy between them as a frontline EVT for patients with large vessel occlusions. This facilitates further investigation to confirm better frontline EVT for patients with acute stroke. In this review, we discuss past and recent developments in CA techniques, focusing on related literature. Additionally, we describe practical skills to overcome technical difficulties that can be encountered during the CA procedure. Finally, we review the evolution of device technologies, including a newer version of using a large-bore aspiration catheter.