New Class of Radially Adjustable Stentrievers for Acute Ischemic Stroke: Primary Results of the Multicenter TIGER Trial

Clinical characteristics of aneurysmal subarachnoid haemorrhage complicated by Takotsubo cardiomyopathy resulting in good neurological outcome

BACKGROUND

Takotsubo cardiomyopathy (TC) is a well-known complication of subarachnoid haemorrhage (SAH), often accompanied by neurogenic myocardial dysfunction. Although TC has been reported to be associated with higher morbidity and mortality among patients with aneurysmal SAH (aSAH), some patients have been reported to recover, the profiles and follow-up outcomes of these survivors remain unclear.

MATERIALS AND METHODS

To characterize the profiles of patients with aSAH complicated by TC who experienced favourable outcomes using long-term follow-up data, a consecutive series of patients with aSAH were enrolled and TC diagnosis was based on the revised version of the Mayo Clinic criteria. Clinical outcomes were assessed at 6 months according to modified Rankin Scale scores.

RESULTS

Among 165 consecutive patients with aSAH, 15 cases were complicated by TC, corresponding to an occurrence rate of 9.0%. Five patients with aSAH complicated by TC (33.3%) experienced a favourable outcome, and the mean value of systolic blood pressure on arrival was significantly lower than in those who experienced an unfavourable outcome (p = 0.032).

CONCLUSION

According to analysis, it is possible cardiac dysfunction with decreased cerebral perfusion pressure and catecholamine toxicity transiently worsens conscious disturbance in aSAH complicated by TC. Therefore, it is important to carefully screen patients with aSAH to identify those complicated by TC, and for close collaboration of the multidisciplinary team to design appropriate treatment strategies.

Initial clinical experience with a novel mechanical thrombectomy device-the ThrombX retriever

BACKGROUND AND PURPOSE

The ThrombX Retriever is a novel mechanical thrombectomy device that adjusts the distance between two mesh segments to axially hold thrombus. A post-market study assessed safety and performance in acute ischemic stroke patients with large artery occlusion.

METHODS

A single-arm prospective multi-center study enrolled patients at 5 European Centers. Patients had a symptomatic large-artery occlusion of the intracranial Internal Carotid or the Middle Cerebral Artery, M1 segment. The primary outcome measure was the modified treatment in cerebral infarction (mTICI) score, on the immediate post-procedure angiogram after up to three device passes. Key secondary outcome measures were the mTICI score after a single pass and functional independence, defined as an mRS score ≤ 2 at 90 days.

RESULTS

Thirty patients (16 Females, mean age 72 years), with NIHSS 4-25 (mean 15.5) were treated. Twenty-eight (93%) achieved mTICI 2b-3 within 3 passes, and 24 (80%) were with the first pass (FP). FP mTICI 2c-3 reperfusion was achieved in 19 (63%) cases. Seventeen of 24 (71%) patients treated with a balloon guide and the ThrombX Retriever had a FP mTICI 2c-3 reperfusion. After all interventions, mTICI 2b-3 was seen in 30 (100%) patients. Twenty-one of the 29 (73%) patients with 90-day follow-up were functionally independent (mRS≤2). No device-related serious adverse events were observed.

CONCLUSION

This preliminary study suggests the ThrombX Retriever is safe and has a high rate of substantial reperfusion. A larger prospective trial to assess the device effectiveness is planned.

RapidpulseTM cyclic aspiration system for acute ischemic stroke due to large vessel occlusions

BACKGROUND

The best strategy to achieve optimal reperfusion outcomes during mechanical thrombectomy remains to be defined. The RapidPulseTM Cyclic Aspiration System is a novel technology, delivering high-frequency pulsed vacuum forces to increase the efficiency of aspiration thrombectomy.

METHODS

Prospective, multicenter, open-label, core lab-adjudicated, two-arm study comparing safety and efficacy of a feasibility version of the RapidPulseTM system compared with contemporary controls. Primary endpoint was the rate of mTICI ≥ 2c after first-pass effect (FPE). Additional efficacy endpoints were the rates of mTICI ≥ 2b after first pass (modified FPE (mFPE)), last pass with study device defined as frontline technical success, and after all passes including rescue therapy. The primary safety endpoints included symptomatic ICH (sICH) within 24 h post-procedure.

RESULTS

Between February 2022 to December 2022, 80 subjects were consented and enrolled in the study (n = 40 treatment arm, n = 40 control arm). In the intent to treat (ITT) population, mean age was 67.8 ± 11.5 years; 19 (47.5%) were male. Median NIHSS score was 16 (IQR: 13-22). Median ASPECTS score was 9 (IQR: 8-10). The rate of mTICI ≥ 2c after first pass was 53.9% in ITT population (60.0% in per-protocol population) versus 38.5% in the corresponding control population. Functional independence (mRS 0-2) at 90 days was achieved in 61.1% (22/36) in the RapidPulseTM arm and 52.8% (19/36) in the control arm. In the RapidPulseTM arm, no sICH within 24 h and no device-related morbidity or mortality occurred.

CONCLUSION

Preliminary data suggests RapidPulseTM Aspiration System is highly effective and safe for recanalization of large vessel occlusions.

The Effect of Out-of-Hours Admission on Mortality in Patients Who Underwent Thrombectomy Due to Ischemic Stroke

Background

It is important to investigate the factors that may delay the diagnosis and treatment process of ischemic stroke. The aim of this study was to investigate whether in-hospital mortality increased in patients who presented to the emergency department out-of-hours and underwent thrombectomy.

Methods

A total of 59 patients who applied to the emergency department between January 1, 2018 and November 1, 2021 and underwent thrombectomy due to ischemic stroke were included in the study. Patient age, gender, thrombectomy success (successful recanalization), in-hospital mortality status, intracranial hemorrhage status after thrombectomy, and out-of-hours admission status were recorded and compared according to out-of-hours admission status.

Results

Twenty-seven (45.8%) patients were male, and the median age was 74 (61-81) years. Forty-two (71.2%) patients applied to the emergency department out-of-hours. In-hospital mortality occurred in 27 (45.8%) patients. There was no statistically significant difference in out-of-hours admission status between the non-survivor group and the survivor group (non-survivor: 24 [75%]; survivor: 18 [66.7%], p = 0.481). Nor was a statistically significant difference found in the intracranial hemorrhage complication rate of the patients admitted out-of-hours compared to the patients admitted during working hours (out-of-hours: 17 [40.5%]; during working hours: 6 [35.3%], p = 0.712).

Conclusion

No statistically significant difference was found in the rate of in-hospital mortality and intracranial bleeding complications in patients who underwent thrombectomy out of working hours compared to during working hours.

Competitive leptomeningeal flow impact on thrombectomy reperfusion grade rating

BACKGROUND

Competitive leptomeningeal flow (CLF) can be observed immediately after mechanical thrombectomy (MT) reperfusion with retrograde contrast clearing of the distal leptomeningeal branches from non-contrast opacified flow through different vascular territories. We aim to evaluate the frequency of the CLF phenomenon, to determine if it has an association with the degree of leptomeningeal collateral status, and to understand the potentia impact it may have on the final expanded Treatment in Cerebral Ischemia (eTICI) score rating.

METHODS

Retrospective analysis of a prospective MT database spanning November 2020 to December 2021. Consecutive cases of intracranial internal carotid (i-ICA) or middle cerebral artery (MCA) M1 occlusions were included. CLF was defined by the observation of retrograde clearing of distal MCA branches that were previously opacified by antegrade reperfusion. The clearance of the distal branches is presumed to occur due to CLF via non-contrast opacified posterior cerebral artery or anterior cerebral artery flow. The washout was considered CLF if it cleared abruptly with or without forward reconstitution of antegrade opacification.

RESULTS

A total of 125 patients met the inclusion criteria. The median age was 64 years (IQR 52.5-75) and 64 (51%) were men. The baseline median National Institutes of Health Stroke Scale score was 17 (IQR 12-22) and the Alberta Stroke Program Early CT Score was 9 (IQR 8-10). Median last known well time to puncture was 7 hours (IQR 4-13.1) and 30.4% received tissue plasminogen activator. Final eTICI 2c-3 was achieved in 80%. CLF was present in 32 (25.6%) patients, who had comparable baseline characteristics to patients without CLF. Twelve (37.5%) patients had regional CLF and 20 (62.5%) had focal CLF. The CLF arm had better leptomeningeal single-phase CTA collaterals than the non-CLF arm (P=0.01). The inter-rater agreement for the eTICI score was moderate when CLF was present and strong in its absence (Krippendorf's alpha=0.65 and 0.81, respectively). There was minimal agreement (Kappa=0.3) for the presence versus absence of CLF between the two operators, possibly related to reader experience.

CONCLUSION

CLF was observed in 32% of patients, was associated with better collateral flow, and impacted the reported procedural eTICI rating.

Thrombectomy With the pRESET vs Solitaire Stent Retrievers as First-Line Large Vessel Occlusion Stroke Treatment: A Randomized Clinical Trial

Importance

Stent retriever-based thrombectomy is highly beneficial in large vessel occlusion (LVO) strokes. Many stent retriever designs are currently available, but comparison of these technologies in well-conducted studies is lacking.

Objective

To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever.

Design, Setting, and Participants

This study was a multicenter, prospective, randomized, controlled, open-label, adaptive, noninferiority trial with blinded primary end point evaluation. Between October 2019 and February 2022, multicenter participation occurred across 19 research hospitals and/or universities in the US and 5 in Germany. Patients with LVO stroke were enrolled and included up to 8 hours after symptom onset.

Interventions

Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever.

Main Outcomes and Measures

The primary outcome was the difference in the rate of 90-day functional independence across the 2 devices, using a -12.5% noninferiority margin for the lower bound of the 1-sided 95% CI of the difference between pRESET and Solitaire retrievers.

Results

Of 340 randomized patients, 170 (50.0%) were female, and the median (IQR) age was 73.0 (64.0-82.0) years. The study procedure was completed in 322 of the 340 randomized patients. The primary end point of 90-day functional independence was achieved by 95 patients (54.9%; 95% CI, 48.7-61.1) in the pRESET group and in 96 (57.5%; 95% CI, 51.2-63.8) in the Solitaire group (absolute difference, -2.57%; 95% CI, -11.42 to 6.28). As the lower bound of the 95% CI was greater than -12.5%, the pRESET retriever was deemed noninferior to the Solitaire retriever. The noninferiority of pRESET over Solitaire was also observed in the secondary clinical end point (90-day shift in modified Rankin Scale score) and in both angiographic end points (Expanded Treatment in Cerebral Infarction [eTICI] score of 2b50 or greater within 3 passes: 146 of 173 [84.4%] vs 149 of 167 [89.2%]; absolute difference, -4.83%; 95% CI, -10.84 to 1.19; eTICI of 2c or greater following the first pass: 76 of 173 [43.7%] vs 74 of 167 [44.3%]; absolute difference, -0.63%; 95% CI, -9.48 to 8.21). Symptomatic intracranial hemorrhage occurred in 0 patients in the pRESET group and 2 (1.2%) in the Solitaire group. Mortality occurred in 25 (14.5%) in the pRESET group and in 24 (14.4%) in the Solitaire group at 90 days. Findings of the per-protocol and as-treated analyses were in concordance with findings of the intention-to-treat analysis.

Conclusions and Relevance

In this study, among patients with LVO stroke, thrombectomy with the pRESET stent retriever was noninferior to thrombectomy with the Solitaire stent retriever. Findings suggest that pRESET offers a safe and effective option for flow restoration and disability reduction in patients with LVO stroke.

Tigertriever in the treatment of acute ischemic stroke with underlying intracranial atherosclerotic disease

BACKGROUND

The Tigertriever device offers a unique feature that enables gradual control of the radial expansion. We sought to evaluate the safety and efficacy of the Tigertriever device in patients with large vessel occlusion (LVO) and underlying intracranial atherosclerotic disease (ICAD). The patients were part of the TIGER trial.

METHODS

The presence of underlying ICAD was determined by a core imaging laboratory using CT angiography and digital subtraction angiography. The primary outcomes included successful reperfusion, puncture to reperfusion time, and complications associated with the use of the Tigertriever device. Patients underwent mechanical thrombectomy with the Tigertriever device for up to three passes, and alternative devices were employed for subsequent passes.

RESULTS

A total of 160 patients were enrolled in the TIGER trial, and 32 patients had ICAD. Among the patients with ICAD, 78% achieved successful reperfusion within three passes of the Tigertriever device, without requiring rescue therapy. Additionally, a first pass effect was observed in 46.8%. The median time from puncture to reperfusion was 22 minutes. There were no device-related complications. The National Institutes of Health Stroke Scale (NIHSS) score at 24 hours was significantly reduced, from an average of 17 at baseline to 8. At the 3 month follow-up, 50% of patients achieved a modified Rankin Scale score of ≤2.

CONCLUSION

Endovascular therapy (EVT) with the Tigertriever device for LVO in patients with underlying ICAD is effective and safe. When compared with historical data from other devices employed in similar cases, we observed a high rate of successful reperfusion, along with a shorter puncture to reperfusion time.

Radially adjustable stent retriever for mechanical thrombectomy in acute ischemic stroke: Improved first-pass effect with rapid-inflation deflation technique

INTRODUCTION

Evidence for improved first-pass effect with the novel radially adjustable radio-opaque stent retriever Tigertriever is lacking.

OBJECTIVE

To compare improvement in first pass success with Tigertriever using two different techniques-rapid inflation deflation (RID) and suction thrombectomy (ST).

METHODS

Retrospective analysis of patients with acute ischemic stroke who underwent mechanical thrombectomy with Tigertriever at a single comprehensive stroke center.

RESULTS

Thirty patients were included. Mean age was 72.8 years. Twelve patients (48%) experienced successful first passes with Tigertriever. Successful revascularization (modified thrombolysis in cerebral infarction (mTICI) 2b/3) was achieved in all (100%) patients who received RID or ST technique for thrombectomy. Good clinical outcome (modified Rankin score = 0-2) was noted in 40% (n = 10). Total mortality in the cohort was 8% (n = 2). RID and ST groups comprised of 10 and 15 patients, respectively. Five patients underwent MT with Tigertriever as a rescue device.

RID VS ST

No difference was noted in mean age (p = 0.27), gender (p = 0.29), location of occlusion (p = 0.46), and device used for first pass (p = 0.57). A 70% first-pass success rate in RID group and 37.5% in ST group was noticed (p = 0.06). Mean time from groin puncture to reperfusion (TICI 2b//3) was statistically similar (p = 0.29, RID: 19.9 min vs ST: 25 min). Both groups noted a 100% complete recanalization rate. The rate of mortality between the two groups were not statistically different (p = 0.46).

CONCLUSION

The preliminary first-pass success rates of RID technique with Tigertriever compared to ST technique, are encouraging. Longitudinal studies with longer follow up are needed to elucidate the smaller learning curve with this device.

Randomized Clinical Trials in Cerebrovascular Neurosurgery From 2018 to 2022

There has been an exponential increase in randomized controlled trials (RCTs) on cerebrovascular disease within neurosurgery. The goal of this study was to review, outline the scope, and summarize all phase 2b and phase 3 RCTs impacting cerebrovascular neurosurgery practice since 2018. We searched PubMed, MEDLINE, Embase, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases for relevant RCTs published between January 1, 2018, and July 1, 2022. We searched for studies related to eight major cerebrovascular disorders relevant to neurosurgery, including acute ischemic stroke, cerebral aneurysms and subarachnoid hemorrhage, intracerebral hemorrhage, subdural hematomas, cerebral venous thrombosis, arteriovenous malformations, Moyamoya disease and extracranial-intracranial bypass, and carotid and intracranial atherosclerosis. We limited our search to phase 2b or 3 RCTs related to cerebrovascular disorders published during the study period. The titles and abstracts of all relevant studies meeting our search criteria were included. Pediatric studies, stroke studies related to rehabilitation or cardiovascular disease, study protocols without published results, prospective cohort studies, registry studies, cluster randomized trials, and nonrandomized pivotal trials were excluded.  From an initial total of 2,797 records retrieved from the database searches, 1,641 records were screened after duplicates and studies outside of our time period were removed. After screening, 511 available reports within our time period of interest were assessed for eligibility. Pediatric studies, stroke studies related to rehabilitation or cardiovascular disease, study protocols without published results, prospective cohort studies, registry studies, cluster randomized trials, and nonrandomized pivotal trials were excluded. We found 80 unique phase 2b or 3 RCTs that fit our criteria, with 165 topic-relevant articles published within the study period.  Numerous RCTs in cerebrovascular neurosurgery have been published since 2018. Ischemic stroke, including mechanical thrombectomy and thrombolysis, accounted for a majority of publications, but there were large trials in intracerebral hemorrhage, subdural hemorrhage, aneurysms, subarachnoid hemorrhage, and cerebral venous thrombosis, among others. This review helps define the scope of the large RCTs published in the last four years to guide future research and clinical care.

Primary results from the CLEAR study of a novel stent retriever with drop zone technology

BACKGROUND

Challenges to revascularization of large vessel occlusions (LVOs) persist. Current stent retrievers have limited effectiveness for removing organized thrombi. The NeVa device is a novel stent retriever designed to capture organized thrombi within the scaffold during retrieval.

OBJECTIVE

To evaluate the safety and effectiveness of revascularization of acute LVOs with the NeVa device.

METHODS

Prospective, international, multicenter, single-arm, Investigational Device Exemption study to evaluate the performance of the NeVa device in recanalizing LVOs including internal carotid artery, M1/M2 middle cerebral artery, and vertebrobasilar arteries, within 8 hours of onset. Primary endpoint was rate of expanded Treatment in Cerebral Ischemia (eTICI) score 2b-3 within 3 NeVa passes, tested for non-inferiority against a performance goal of 72% with a -10% margin. Additional endpoints included first pass success and 90-day modified Rankin Scale (mRS) score 0-2. Primary composite safety endpoint was 90-day mortality and/or 24-hour symptomatic intracranial hemorrhage (sICH).

RESULTS

From April 2021 to April 2022, 139 subjects were enrolled at 25 centers. Median National Institutes of Health Stroke Scale (NIHSS) score was 16 (IQR 12-20). In the primary analysis population (n=107), eTICI 2b-3 within 3 NeVa passes occurred in 90.7% (97/107; non-inferiority P<0.0001; post hoc superiority P<0.0001). First pass eTICI 2b-3 was observed in 73.8% (79/107), with first pass eTICI 2b67-3 in 69.2% (74/107) and eTICI 2c-3 in 48.6% (52/107). Median number of passes was 1 (IQR 1-2). Final eTICI 2b-3 rate was 99.1% (106/107); final eTICI 2b67-3 rate was 91.6% (98/107); final eTICI 2c-3 rate was 72.9% (78/107). Good outcome (90-day mRS score 0-2) was seen in 65.1% (69/106). Mortality was 9.4% (13/138) with sICH in 5.0% (7/139).

CONCLUSIONS

The NeVa device is highly effective and safe for revascularization of LVO strokes and demonstrates superior first pass success compared with a predicate performance goal.

TRIAL REGISTRATION NUMBER

NCT04514562.

Outcomes with Endovascular Treatment of Patients with M2 Segment MCA Occlusion in the Late Time Window

BACKGROUND AND PURPOSE

Randomized trials in the late window have demonstrated the efficacy and safety of endovascular thrombectomy in large-vessel occlusions. Patients with M2-segment MCA occlusions were excluded from these trials. We compared outcomes with endovascular thrombectomy in patients with M2-versus-M1 occlusions presenting 6-24 hours after symptom onset.

MATERIALS AND METHODS

Analyses were on pooled data from studies enrolling patients with stroke treated with endovascular thrombectomy 6-24 hours after symptom onset. We compared 90-day functional independence (mRS ≤ 2), mortality, symptomatic intracranial hemorrhage, and successful reperfusion (expanded TICI = 2b-3) between patients with M2 and M1 occlusions. The benefit of successful reperfusion was then assessed among patients with M2 occlusion.

RESULTS

Of 461 patients, 367 (79.6%) had M1 occlusions and 94 (20.4%) had M2 occlusions. Patients with M2 occlusions were older and had lower median baseline NIHSS scores. Patients with M2 occlusion were more likely to achieve 90-day functional independence than those with M1 occlusion (adjusted OR = 2.13; 95% CI, 1.25-3.65). There were no significant differences in the proportion of successful reperfusion (82.9% versus 81.1%) or mortality (11.2% versus 17.2%). Symptomatic intracranial hemorrhage risk was lower in patients with M2-versus-M1 occlusions (4.3% versus 12.2%, P = .03). Successful reperfusion was independently associated with functional independence among patients with M2 occlusions (adjusted OR = 2.84; 95% CI, 1.11-7.29).

CONCLUSIONS

In the late time window, patients with M2 occlusions treated with endovascular thrombectomy achieved better clinical outcomes, similar reperfusion, and lower symptomatic intracranial hemorrhage rates compared with patients with M1 occlusion. These results support the safety and benefit of endovascular thrombectomy in patients with M2 occlusions in the late window.

Desired Qualities of Endovascular Tools and Barriers to Treating Medium Vessel Occlusion MeVO : Insights from the MeVO-FRONTIERS International Survey

BACKGROUND

Endovascular treatment (EVT) for stroke due to medium vessel occlusion (MeVO) can be technically challenging and specific endovascular tools are needed to safely and effectively recanalize these relatively small and fragile vessels. We aimed to gain insight into availability and desired qualities of endovascular devices used in MeVO stroke and examined barriers to adoption of MeVO EVT in clinical practice on a global scale.

METHODS

We conducted a case-based international survey among neurointerventionalists. As a part of the survey, participants were asked whether they felt appropriate endovascular tools for MeVO stroke exist and are available to them in their clinical practice. We then examined barriers to adopting MeVO EVT and analyzed them by geographic regions.

RESULTS

A total of 263 neurointerventionists participated, of which 178 (67.7%) and 83 (31.6%) provided responses on desired qualities of MeVO EVT tools and on barriers to their adoption in local practice, respectively. The majority 121/178 (68%) felt there was substantial room for improvement regarding existing tools. A large proportion 131/178 (73.6%) felt they had appropriate access to existing tools. The most commonly mentioned barrier for adopting MeVO EVT in North America was "awaiting better tools" (9/28 responses, 32.1%), while "awaiting better evidence" (8/26 responses, 30.8%), and the need for improved "funding" (7/26 responses, 26.9%) were important barriers in Europe.

CONCLUSION

The majority of surveyed neurointerventionalists felt that dedicated MeVO EVT tools can be substantially improved upon. Different regions face various challenges in adoption of MeVO EVT, but overall, physicians are mostly awaiting better MeVO EVT tools.

Mechanical thrombectomy of large vessel occlusion using adjustable vs. self-expanding stent-retriever-Comparison of Tigertriever device with stent-like stent-retrievers: A propensity score analysis

Background

Stent-retrievers used for mechanical thrombectomy are self-expanding tubular stent-like devices with modified mesh structures for clot removal. Tigertriever is designed to provide manual control of its diameter and curvature.

Methods

A retrospective single-center study was performed to compare Tigertriever with SolitaireX and pRESET (stent-like stent-retrievers group) using propensity score analysis. Patients treated in a comprehensive stroke center due to large vessel occlusion between January 2016 and August 2021 were evaluated. Baseline characteristics and treatment results were compared between these groups before and after pair matching.

Results

There were 140 patients (60 in Tigertriever and 80 in the stent-like stent-retriever group). In propensity score analysis, 52 matched pairs were selected in Tigertriever and stent-like stent-retriever groups. The Tigertriever group had a better successful first pass revascularization rate [46 vs. 23%, OR (95% CI): 1.7 (1.1-2.9), p = 0.013] and 14-min shorter groin-to-revascularization time (51 vs. 65 min. p = 0.017). There were no significant differences between Tigertriever and stent-like stent-retriever groups in the following: favorable mRS 3 months, favorable recanalization rate, and symptomatic intracerebral hemorrhages. There were no observed periprocedural adverse events related to Tigertriever, SolitaireX, or pRESET.

Conclusion

Tigertriever had a significantly better successful first pass revascularization rate and shorter groin-to-revascularization time in the analysis done before and after propensity score matching with stent-like stent-retrievers. Tigertriever is comparable to stent-like stent-retrievers regarding mortality at 3 months, favorable mRS at 3 months, favorable recanalization rate, or symptomatic cerebral hemorrhagic events.

The initial experience with the Embotrap III stent-retriever in a real world setting

MATERIALS AND METHODS

We performed a retrospective review of our prospectively maintained database to identify all patients treated with the Embotrap 3 stent-retriever between January 2021 and January 2022. We recorded the baseline demographics, NIHSS, ASPECT score and clot characteristics, first pass and final eTICI scores, complications and 90 day mRS.

RESULTS

One hundred and ten patients met the inclusion criteria, average age 69 ± 14 years, 50% were male (n = 55). The median NIHSS at presentation was 18 (range 3-30) and 58.2% received IV tPA prior to MT. The median ASPECT score on plain CT was 8 with average clot length 20.2 ± 14.8 mm (n = 93). The first pass effect (FPE) was seen in 41.8% of cases with modified FPE seen in 59.1%. A 24-hour CT scan (n = 97) showed median ASPECTs of 7. 43.8% of patients achieve mRS ≤ 2 at 90-day mRS (n = 64).

CONCLUSION

The Embotrap 3 stent-retriever has a high rate of FPE and final recanalization in this real world cohort of patients.

First Experience with the Nimbus Stentretriever

Purpose

To share our first experience with the Nimbus stentretriever, a multizone device designed to assist neurointerventionalists in handling fibrin-rich clots in endovascular stroke treatment.

Methods

We retrospectively analyzed the data of patients who were treated with the Nimbus stentretriever at our high-volume stroke center between May 2021 and May 2022. We evaluated the number of passes before Nimbus was used, the number of passes with nimbus, as well as the recanalization success before and after Nimbus according to the modified treatment in cerebral ischemia (mTICI) scale. Also, patient characteristics, procedural times and clinical outcomes were documented.

Results

A total of 21 consecutive patients were included in the study. An mTICI 2b/3 could be achieved in 76.2% and mTICI 2c/3 could be achieved in 57.1%. The mean number of passes was 3.4 before the use of Nimbus, 2.2 with Nimbus, and 5.4 for all passes with and without Nimbus and 4 occlusions (19.0%) were successfully recanalized with direct aspiration after the use of Nimbus. We observed seven subarachnoid hemorrhages (33.3%) and two cases of vasospasm.

Conclusion

In our series, the use of Nimbus resulted in successful recanalization in half of the patients after otherwise unsuccessful thrombectomy maneuvers; therefore, it should be considered as a rescue option if the maneuver with conventional stent retrievers was unsuccessful.

Patient and procedure selection for mechanical thrombectomy: Toward personalized medicine and the role of artificial intelligence

Mechanical thrombectomy (MT) for ischemic stroke due to large vessel occlusion is standard of care. Evidence-based guidelines on eligibility for MT have been outlined and evidence to extend the treatment benefit to more patients, particularly those at the extreme ends of a stroke clinical severity spectrum, is currently awaited. As patient selection continues to be explored, there is growing focus on procedure selection including the tools and techniques of thrombectomy and associated outcomes. Artificial intelligence (AI) has been instrumental in the area of patient selection for MT with a role in diagnosis and delivery of acute stroke care. Machine learning algorithms have been developed to detect cerebral ischemia and early infarct core, presence of large vessel occlusion, and perfusion deficit in acute ischemic stroke. Several available deep learning AI applications provide ready visualization and interpretation of cervical and cerebral arteries. Further enhancement of AI techniques to potentially include automated vessel probe tools in suspected large vessel occlusions is proposed. Value of AI may be extended to assist in procedure selection including both the tools and technique of thrombectomy. Delivering personalized medicine is the wave of the future and tailoring the MT treatment to a stroke patient is in line with this trend.

Clinical Results of the Advanced Neurovascular Access Catheter System Combined With a Stent Retriever in Acute Ischemic Stroke (SOLONDA)

BACKGROUND

The Advanced Neurovascular Access (ANA) thrombectomy system is a novel stroke thrombectomy device comprising a self-expanding funnel designed to reduce clot fragmentation by locally restricting flow while becoming as wide as the lodging artery. Once deployed, the ANA device allows distal aspiration combined with a stent retriever to mobilize the clot into the funnel where it remains copped during extraction. We investigated the safety and efficacy of ANA catheter system.

METHODS

SOLONDA (Solitaire in Combination With the ANA Catheter System as Manufactured by Anaconda) was a prospective, open, single-arm, multicenter trial with blinded assessment of the primary outcome by an independent core lab. Patients with anterior circulation vessel occlusion admitted within 8 hours from symptom onset were eligible. The primary end point was successful reperfusion (modified Thrombolysis in Cerebral Infarction score 2b-3) with ≤3 passes of the ANA device in combination with stent retriever, before the use of rescue therapy in the intention to treat population. Primary predefined analysis was noninferiority as compared to the performance end point observed in HERMES (High Effective Reperfusion Using Multiple Endovascular Devices).

RESULTS

After enrollment of 74 patients, an interim analysis was conducted, and the trial Steering Committee decided to terminate recruitment due to safety and performance objectives were reached. Mean age was 71.6 (SD 8.9) years, 46.6% women and median National Institutes of Health Stroke Scale on admission 14 (interquartile range, 10-19). Successful reperfusion within 3 passes before rescue therapy was achieved in 60/72 (83.3% [95% CI, 74.7%-91.9%]) with a rate of complete reperfusion (modified Thrombolysis in Cerebral Infarction score 2c-3) of 60% (95% CI, 48.4%-71.1%; 43/72 patients). After noninferiority was confirmed (P<0.01), the ANA device also showed superiority in the rate of successful reperfusion with ≤3 passes (P=0.02). First-pass successful recanalization rate was 55.6% (95% CI, 44.1%-67.0%), with a first-pass complete recanalization rate of 38.9% (95% CI, 27.6%-50.1%). Rescue therapy to obtain a modified Thrombolysis in Cerebral Infarction score 2b-3 was needed in 12/72 (17%) patients. At 90 days, the rate of favorable functional outcome (modified Rankin Scale score 0-2) was 57.5% (95% CI, 46.2%-68.9%), and the rate of excellent functional outcome (modified Rankin Scale score 0-1) was 45.2% (95% CI, 33.8%-56.6%). The rate of severe adverse device related was 1.4%.

CONCLUSIONS

In this clinical experience, the ANA device achieved a high rate of complete recanalization with a preliminary good safety profile and favorable 90 days clinical outcomes.

The Tigertriever 13 for mechanical thrombectomy in distal and medium intracranial vessel occlusions

PURPOSE

To report our two-center initial experience using the Tigertriever 13 in the treatment of acute stroke of distal, medium vessel occlusions (DMVO).

METHODS

We performed a retrospective analysis of all patients treated by mechanical thrombectomy using the Tigertriever 13 device (a manually expandable low profile stent retriever) due to an acute DMVO. Locations included the anterior, middle, and posterior cerebral artery in the A2 and A3, the M3 and M4, and the P2 or P3 segment and the superior cerebellar artery.

RESULTS

Forty-three patients with 45 DMVOs underwent MTE using the Tigertriever 13 with the intention-to-treat approach between May 2019 and December 2020. After a median of two thrombectomy maneuvers, the successful recanalization rate (mTICI 2b-3) was 84.4% (38/45) with a first pass effect of 26.7% (12/45). The rate of symptomatic intracranial hemorrhages (sICH) and subarachnoid hemorrhages (SAH) was 7.0% (3/43) and 14.0% (6/43), respectively. At discharge, 53.5% (23/43) of the patients had a favorable clinical outcome (mRS 0-2).

CONCLUSION

Mechanical thrombectomy in DMVOs using the Tigertriever 13 leads to high recanalization rates. The incidence of mostly asymptomatic hemorrhagic events appears higher compared to MTE procedures in LVOs. Further studies will help to identify anatomic and clinical criteria to define a guideline for MTE in DMVOs.

Evidence-Based Updates to Thrombectomy: Targets, New Techniques, and Devices

Endovascular thrombectomy (EVT) has been validated in several randomized controlled trials in recent years for its efficacy in the treatment of acute ischemic strokes (AIS) and is now the standard of care according to international guidelines. However, in about 20% of EVT procedures, recanalization is not achieved, and over 50% of patients who undergo EVT still do not have good functional outcome. In this article, we provide an extensive review of the latest evidence and developments in the field of EVT, with particular focus on the factors that improve patient outcomes. These factors include new and adjunctive techniques such as combination of direct aspiration and stent retriever, intra-arterial urokinase or 2b/3a inhibitors, rescue stenting, as well as novel devices including balloon guide catheters and the newer generations of aspiration catheters and stent retrievers. We also examined the latest notion of using first-pass effect (FPE) as the target to achieve during EVT, which has been associated with an improved functional outcome. While the field of EVT has been rapidly evolving, further research is required in specific AIS patient populations such as those with large ischemic core, late presentation beyond 24 h, posterior circulation strokes, and with distal medium vessel occlusion or tandem lesions to better assess its efficacy and safety.

Efficacy and Safety of a Novel Thrombectomy Device in Patients With Acute Ischemic Stroke: A Randomized Controlled Trial

Purpose: The Tonbridge stent is a novel retriever with several design improvements which aim to achieve promising flow reperfusion in the treatment of acute ischemic stroke (AIS). We conducted a randomized controlled, multicenter, non-inferiority trial to compare the safety and efficacy of the Tonbridge stent with the Solitaire FR. Methods: AIS patients aged 18-85 years with large vessel occlusion in anterior circulation who could undergo puncture within 6 h of symptom onset were included. Randomization was performed on a 1:1 ratio to thrombectomy with either the Tonbridge stent or the Solitaire FR. The primary efficacy endpoint was successful reperfusion using a modified thrombolysis in cerebral infarction score (mTICI) of 2b/3. Safety outcomes were symptomatic intracranial hemorrhage (sICH) within 24 ± 6 h and all-cause mortality within 90 days. A clinically relevant non-inferiority margin of 12% was chosen as the acceptable difference between groups. Secondary endpoints included time from groin puncture to reperfusion, National Institutes of Health Stroke Scale (NIHSS) score at 24 h and at 7 days, and a modified Rankin Scale (mRS) score of 0-2 at 90 days. Results: A total of 220 patients were enrolled; 104 patients underwent thrombectomy with the Tonbridge stent and 104 were treated with the Solitaire FR. In all test group patients, the Tonbridge was used as a single retriever without rescuing by other thrombectomy devices. Angioplasty with balloon and/or stent was performed in 26 patients in the Tonbridge group and 16 patients in the Solitaire group (p = 0.084). Before angioplasty, 86.5% of those in the Tonbridge group and 81.7% of those in the Solitaire group reached successful reperfusion (p = 0.343). Finally, more patients in the Tonbridge group achieved successful reperfusion (92.3 vs. 84.6%, 95% CI of difference value 0.9-16.7%, p < 0.0001). There were no significant differences on sICH within 24 ± 6 h between the two groups. All-cause mortality within 90 days was 13.5% in the Tonbridge group and 16.3% in the Solitaire group (p = 0.559). We noted no significant differences between groups on the NIHSS at either 24 h or 7 days and the mRS of 0-2 at 90 days. Conclusion: The trial indicated that the Tonbridge stent was non-inferior to the Solitaire FR within 6 h of symptom onset in cases of large vessel occlusion stroke. Clinical Trial Registration:ClinicalTrials.gov, number: NCT03210623.

Mechanical Thrombectomy in Acute Terminal Internal Carotid Artery Occlusions Using a Large Manually Expandable Stentretriever (Tiger XL Device): Multicenter Initial Experience

Background: The recently introduced Tigertriever XL Device for treatment of cerebral vessel occlusions combines manual adjustability and maximum length in one device. In this study, we report our initial experience with the Tigertriever XL in terminal ICA occlusions. Methods: Retrospective multicenter analysis of acute terminal ICA occlusions treated by mechanical thrombectomy using the Tigertriever XL Device. Results: 23 patients were treated using the Tigetriever XL due to an acute occlusion of the terminal ICA. The overall successful reperfusion rate after a median of two maneuvers using the Tigertriever XL Device was 78.3% (mTICI 2b-3). In 43.5% (10/23) additional smaller devices were applied to treat remaining occlusions in downstream territories, which resulted in a final successful reperfusion rate of 95.7%. Device related complications did not occur. Two symptomatic intracerebral hemorrhages (sICH) were observed. Conclusions: The Tigertriever XL Device might be a helpful tool in the treatment of ICA terminus occlusions with large clot burden resulting in high reperfusion rates. This is mainly related to the manual adjustability of the device combined with the maximum length.

Initial Experience With the Trevo NXT Stent Retriever

Background: The application of a new coating to the delivery wire of the Trevo retriever has the potential to improve its handling. We therefore report our initial experience with this new stent retriever for mechanical thrombectomy of large and medium vessel occlusions. Methods: We pooled data of four high-volume European stroke centers over the time period from October 2020 to February 2021. Patients were included in our study if the Trevo NXT stent retriever was used as a first-line device. Primary endpoints were first-pass near-complete or complete reperfusion, defined as mTICI score of ≥2c. Secondary endpoints were final reperfusion, National Institutes of Health Stroke Scale (NIHSS) at 24 h and discharge, device malfunctions, complications during the procedure, and subjective ratings of the interventionalists regarding device functionality. Results: Eighty patients (39 women, mean age 74 ± 14 years) were eligible for our study. Median NIHSS at admission was 15 (IQR, 8-19), and median Alberta Stroke Program Early CT Score at baseline was 9 (IQR, 8-10). In 74 (93%) patients a primary combined approach was used as first-line technique. First-pass near-complete reperfusion was achieved in 43 (54%) and first-pass complete reperfusion in 34 (43%) patients. Final near-complete reperfusion was achieved in 66 (83%) patients after a median of 1.5 (1-3) passes, while final successful reperfusion was observed in 96% of our cases. We observed no device malfunctions. Median NIHSS at discharge was 2 (IQR, 0-5), and 3 patients (4%) suffered a symptomatic intracranial hemorrhage. Conclusions: Based on our initial data, we conclude that the Trevo NXT is an effective and safe tool for mechanical thrombectomy especially when used for combined approaches.

How to Improve the Management of Acute Ischemic Stroke by Modern Technologies, Artificial Intelligence, and New Treatment Methods

Stroke remains one of the leading causes of death and disability in Europe. The European Stroke Action Plan (ESAP) defines four main targets for the years 2018 to 2030. The COVID-19 pandemic forced the use of innovative technologies and created pressure to improve internet networks. Moreover, 5G internet network will be helpful for the transfer and collecting of extremely big databases. Nowadays, the speed of internet connection is a limiting factor for robotic systems, which can be controlled and commanded potentially from various places in the world. Innovative technologies can be implemented for acute stroke patient management soon. Artificial intelligence (AI) and robotics are used increasingly often without the exception of medicine. Their implementation can be achieved in every level of stroke care. In this article, all steps of stroke health care processes are discussed in terms of how to improve them (including prehospital diagnosis, consultation, transfer of the patient, diagnosis, techniques of the treatment as well as rehabilitation and usage of AI). New ethical problems have also been discovered. Everything must be aligned to the concept of “time is brain”.