Comparison of the efficacy and safety of thrombectomy devices in acute stroke : a network meta-analysis of randomized trials

Comparative efficacy and safety of various mechanical thrombectomy strategies for patients with acute ischemic stroke: a Bayesian network meta-analysis

Background

Stent retriever, contact aspiration, and combined treatment are crucial mechanical thrombectomy strategies for patients with acute ischemic stroke (AIS).

Objectives

The aim of this study was to compare and rank three different mechanical thrombectomy strategies for AIS due to large vessel occlusion by means of a Bayesian network meta-analysis.

Design

A systematic review and Bayesian network meta-analysis based on PRISMA guidelines.

Data sources and methods

Relevant randomized controlled trials (RCTs) were identified in Embase, MEDLINE, the Cochrane Library database, and Clinicaltrials.gov from inception to 15 March 2022. We used random effect models to estimate corresponding odds ratios (ORs) and rank probabilities using pairwise and Bayesian network meta-analysis. We applied the grading of recommendations assessment, development, and evaluation (GRADE) methodology to rate the certainty of evidence.

Results

We identified 10 RCTs enrolling 2098 participants. As for modified Rankin Scale (mRS) 0-2, moderate certainty evidence established all mechanical thrombectomy strategies that were more effective than standard medical treatment [combined: log OR 0.9288, 95% credibility intervals (CrI) 0.1268-1.7246; contact aspiration: log OR 0.9507, 95% CrI 0.3361-1.5688; stent retriever: log OR 1.0919, 95% CrI 0.6127-1.5702]. The same applied to mRS 0-3 (combined: log OR 0.9603, 95% CrI 0.2122-1.7157; contact aspiration: log OR 0.7554, 95% CrI 0.1769-1.3279; stent retriever: log OR 1.0046, 95% CrI 0.6001-1.4789). Combined treatment was superior to stent retriever in substantial reperfusion (log OR 0.8921, 95% CrI 0.2105-1.5907, high certainty). Stent retriever had the highest probability of being optimal for mRS 0-2 and mRS 0-3. Standard medical treatment had the lowest risk of subarachnoid hemorrhage. For all other outcomes, combined treatment was most likely the best treatment.

Conclusion

Our results indicated that, with the exception of functional outcome, combined treatment might be the outstanding strategy. Apart from subarachnoid hemorrhage, all three mechanical thrombectomy strategies proved better strategies than standard medical treatment.

Registration

PROSPERO (CRD42022351878).

MASTRO I: Meta-Analysis and Systematic Review of thrombectomy stent retriever outcomes: comparing functional, safety and recanalization outcomes between EmboTrap, Solitaire and Trevo in acute ischemic stroke

Aim: Stent-retriever (SR) thrombectomy has demonstrated superior outcomes in patients with acute ischemic stroke compared with medical management alone, but differences among SRs remain unexplored. We conducted a Systematic Review/Meta-Analysis to compare outcomes between three SRs: EmboTrap®, Solitaire™, and Trevo®. Methods: We conducted a PRISMA-compliant Systematic Review among English-language studies published after 2014 in PubMed/MEDLINE that reported SRs in ≥25 patients. Functional and safety outcomes included 90-day modified Rankin scale (mRS 0-2), mortality, symptomatic intracranial hemorrhage (sICH), and embolization to new territory (ENT). Recanalization outcomes included modified thrombolysis in cerebral infarction (mTICI) and first-pass recanalization (FPR). We used a random effects Meta-Analysis to compare outcomes; subgroup and outlier-influencer analysis were performed to explore heterogeneity. Results: Fifty-one articles comprising 9,804 patients were included. EmboTrap had statistically significantly higher rates of mRS 0-2 (57.4%) compared with Trevo (50.0%, p = 0.013) and Solitaire (45.3%, p < 0.001). Compared with Solitaire (20.4%), EmboTrap (11.2%, p < 0.001) and Trevo (14.5%, p = 0.018) had statistically significantly lower mortality. Compared with Solitaire (7.7%), EmboTrap (3.9%, p = 0.028) and Trevo (4.6%, p = 0.049) had statistically significantly lower rates of sICH. There were no significant differences in ENT rates across all three devices (6.0% for EmboTrap, 5.3% for Trevo, and 7.7% for Solitaire, p = 0.518). EmboTrap had numerically higher rates of recanalization; however, no statistically significant differences were found. Conclusion: The results of our Systematic Review/Meta-Analysis suggest that EmboTrap may be associated with significantly improved functional outcomes compared with Solitaire and Trevo. EmboTrap and Trevo may be associated with significantly lower rates of sICH and mortality compared with Solitaire. No significant differences in recanalization and ENT rates were found. These conclusions are tempered by limitations of the analysis including variations in thrombectomy techniques in the field, highlighting the need for multi-arm RCT studies comparing different SR devices to confirm our findings.

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.

Common Data Elements Reported in Mechanical Thrombectomy for Acute Ischemic Stroke: A Systematic Review of Active Clinical Trials

BACKGROUND

New trials are planned regularly to provide the highest quality of evidence and invade new occlusion territories, which requires a pre-defined reporting strategy with consistent, common data elements for more straightforward collective evidence synthesis. We sought to review all active endovascular thrombectomy trials to investigate their patient selection criteria, intervention description, and reported outcomes.

METHODS

A literature search was systematically conducted on clinicaltrials.gov for active trials and all intervention, inclusion criteria, and outcomes reported were extracted. A qualitative synthesis of the frequency of study design types and data elements are graphically and narratively presented.

RESULTS

A total of 32 studies were tagged and included in the final qualitative analysis. The inclusion criteria were highly variable, including different cut-offs for the last well-known baseline National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, and modified Rankin scale (mRS). Half of the studies (16/32) mentioned "thrombectomy" without defining which technique or device was used, and the final thrombolysis in cerebral infarction scale was provided in 19 (59.4%) studies. Heterogeneity was also present among the studies reporting a first-pass effect, both in how studies defined the outcome and in used ranges for mRS. Mortality and intracerebral hemorrhage (ICH) were more homogenous in their presentation and follow-up.

CONCLUSIONS

There is a great degree of heterogeneity in the active thrombectomy trials concerning inclusion criteria, interventions used, and how outcomes are being reported.

Predictors of first-pass reperfusion for mechanical thrombectomy in acute ischemic stroke

BACKGROUND AND OBJECTIVE

Rapid reperfusion of ischemic penumbra in patients with acute stroke is critical to neurological recovery. Achieving reperfusion after first-pass mechanical thrombectomy has been associated with improved patient outcomes. However, the predictors for obtaining first-pass reperfusion are not well known.

METHODS

A single-institution retrospective study of all patients who underwent mechanical thrombectomy at a tertiary care center from January 2010 until March 2019 was conducted to assess for predictors of first-pass reperfusion.

RESULTS

A total of 257 patients were reviewed. Successful reperfusion was obtained in 63.4% of patients, and in 38% of patients on the first pass. On multivariate analysis, increasing door-to-puncture time was a negative predictor of FPR (OR 0.989, 95% CI = 0.980-0.997) and use of combined thrombectomy technique with stent-retriever and aspiration was a positive predictor of FPR compared to aspiration or stent-retriever alone (OR 4.441, 95% CI = 1.001-19.699).

CONCLUSIONS

Combination therapy using stent-retriever and aspiration may increase the chance of obtaining FPR, whereas delays in starting the procedure after patient arrival may decrease the odds of FPR. Rapid thrombectomy initiation and procedural technique may play in optimizing rates of FPR and ultimately patient outcomes, however, randomized controlled trials assessing these variables are necessary to determine optimal treatment strategies.

RECO Flow Restoration Device Versus Solitaire FR With the Intention for Thrombectomy Study (REDIRECT): a prospective randomized controlled trial

OBJECTIVE

The RECO flow restoration (FR) device is a new stent retriever designed for rapid flow restoration in acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). Here, the authors compared the efficacy and safety of the RECO device with the predicate Solitaire FR stent retriever.

METHODS

The RECO Flow Restoration Device Versus Solitaire FR With the Intention for Thrombectomy Study (REDIRECT) was a multicenter, prospective, open randomized controlled trial. Patients with acute LVO at 7 Chinese stroke centers participated in the study. The primary efficacy endpoint was defined as a modified thrombolysis in cerebral infarction (mTICI) reperfusion grade ≥ 2 within three passes. The primary safety endpoint comprised any serious adverse device effect, symptomatic intracerebral hemorrhage (sICH), and any serious adverse event (SAE; defined as cerebral palsy or death) within 24 hours after the procedure. The secondary efficacy endpoints consisted of functional independence (modified Rankin Scale score 0-2), procedure duration, and 90-day all-cause mortality.

RESULTS

Between January 2014 and August 2016, 67 patients were randomly allocated to the RECO group and 69 patients to the Solitaire FR group. The primary efficacy endpoint (mTICI grade ≥ 2 within three passes) was similar in the two treatment groups (91% vs 87%, respectively, p = 0.5861), and the rate of reperfusion with an mTICI grade 2b/3 was 87% versus 75% (p = 0.1272). There were no serious adverse device effects in any patient. The rates of sICH (1.5% vs 7.2%, p = 0.1027) and SAEs (6.0% vs 1.4%, p = 0.2050) within 24 hours after the procedure were similar in the two treatment groups. There was no significant difference in the rate of functional independence (63% vs 46%, p = 0.0609) or 90-day all-cause mortality (13% vs 23%, p = 0.1848) or in procedure duration (85.39 ± 47.01 vs 89.94 ± 53.34 minutes, p = 0.5986) between the two groups.

CONCLUSIONS

The RECO stent retriever is effective and safe as a mechanical thrombectomy device for AIS due to LVO. Clinical trial registration no.: NCT01983644 (clinicaltrials.gov).

Clinical effectiveness of endovascular stroke treatment in the early and extended time windows

BACKGROUND

The clinical efficacy of mechanical thrombectomy has been unequivocally demonstrated in multiple randomized clinical trials. However, these studies were performed in carefully selected centers and utilized strict inclusion criteria.

AIM

We aimed to assess the clinical effectiveness of mechanical thrombectomy in a prospective registry.

METHODS

A total of 2008 patients from 76 sites across 12 countries were enrolled in a prospective open-label mechanical thrombectomy registry. Patients were categorized into the corresponding cohorts of the SWIFT-Prime, DAWN, and DEFUSE 3 trials according to the basic demographic and clinical criteria without considering specific parenchymal imaging findings. Baseline and outcome variables were compared across the corresponding groups.

RESULTS

As compared to the treated patients in the actual trials, registry-derived patients tended to be younger and had lower baseline ASPECTS. In addition, time to treatment was earlier and the use of intravenous tissue plasminogen activator (IV-tPA) and general anesthesia were higher in DAWN- and DEFUSE-3 registry derived patients versus their corresponding trials. Reperfusion rates were higher in the registry patients. The rates of 90-day good outcome (mRS0-2) in registry-derived patients were comparable to those of the patients treated in the corresponding randomized clinical trials (SWIFT-Prime, 64.5% vs. 60.2%; DAWN, 50.4% vs. 48.6%; Beyond-DAWN: 52.4% vs. 48.6%; DEFUSE 3, 52% vs. 44.6%, respectively; all P > 0.05). Registry-derived patients had significant less disability than the corresponding randomized clinical trial controls (ordinal modified Rankin Scale (mRS) shift odds ratio (OR), P < 0.05 for all).

CONCLUSION

Our study provides favorable generalizability data for the safety and efficacy of thrombectomy in the "real-world" setting and supports that patients may be safely treated outside the constraints of randomized clinical trials.

Favorable first-pass recanalization rates with NeVa™ thrombectomy device in acute stroke patients: Initial clinical experience

BACKGROUND

The NeVa™ thrombectomy device (Vesalio LLC, Nashville, USA) has been reported to succeed in large vessel occlusion thrombectomy in animal, in-vitro, and clinical studies. Designed with Drop Zone technology, a closed distal tip, and strong expansive radial force, the device demonstrated particular efficiency in resistant "white" thrombi in preclinical research. Our goal is to determine the safety and performance of this novel stent retriever on first-pass rates and overall recanalization.

METHODS

The Interventional Neurology Database is a prospectively maintained database of anterior and posterior circulation stroke thrombectomy cases. We retrospectively analyzed cases where the NeVa™ thrombectomy device was used as the first-line treatment strategy. Data collection occurred between January 2019 and January 2020. First-pass recanalization, final recanalization, 90-day functional outcome, complication, and bleeding rates are reported.

RESULTS

One hundred eighteen patients were treated with the NeVa™ thrombectomy device. The mean patient age was 69 ± 14 years, the median baseline National Institutes of Health Stroke Scale was 14, and the median initial Alberta Stroke Program Early Computed Tomography score was 8. The median time from groin puncture to successful recanalization was 29 min (interquartile range (IQR): 20-40). First-pass recanalization rates were 56.8% (modified treatment in cerebral infarction (mTICI) 2b/3) and 44.9% (mTICI 2c/3). Final successful recanalization rate was 95.8% (thrombolysis in cerebral infarction 2b/3). Favorable functional outcome (modified Rankin Scale 0-2) was 53% in the "first-pass" subgroup and 42.4% in the total patient population. The median number of passes to achieve the final recanalization score was 1 (IQR 1-2). The rate of embolization into new territory was 1.7%. Four patients (3.3%) had symptomatic hemorrhage.

CONCLUSIONS

In our experience, the NeVa™ device demonstrated high first-pass and overall recanalization rates along with a good safety profile.

Efficacy and Safety of Recanalization Therapy for Acute Ischemic Stroke With Large Vessel Occlusion

Background and Purpose:

The optimal recanalization strategy for acute ischemic stroke with large vessel occlusion continues to be an area of active interest. Network meta-analysis can provide insight when direct comparative evidence is lacking.

Methods:

A systematic review of the literature using PubMed, Embase, the Cochrane Central Register of Controlled Trials, and SinoMed was performed, and a search was conducted for clinical trials on ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform, and StrokeCenter.org. Four independent reviewers conducted the study selection, data abstraction, and quality assessments.

Results:

The literature review identified 17 trials including 3236 patients and 8 ongoing clinical trials. Sample sizes ranged from 7 to 656 participants. Intravenous thrombolysis (IVT) was the most common intervention, followed by IVT plus mechanical thrombectomy (MT), IVT plus intraarterial thrombolysis, intraarterial thrombolysis alone, and MT alone. In the pooled network meta-analysis, IVT+MT was associated with a higher rate of independent functioning. In contrast, IVT was ranked as the most ineffective treatment strategy with respect to neurological functions, while direct MT was ranked as the least safe intervention with respect to all-cause mortality. Also, irrespective of assessment tools, endovascular treatment plus IVT led to higher successful recanalization rate than thrombolysis alone.

Conclusions:

Compared with other recanalization treatments, IVT+MT seems to be the most effective strategy, without increasing detrimental effects, for thrombolysis-eligible patients with large vessel occlusion-acute ischemic stroke. To improve the current evidentiary basis for recanalization treatment, future trials and real-world studies are warranted and should use unified definitions of symptomatic intracranial hemorrhage and recanalization.

Stent-retriever assisted vacuum-locked extraction (SAVE) versus a direct aspiration first pass technique (ADAPT) for acute stroke: data from the real-world

BACKGROUND

Embolectomy is the standard of care in acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). Aim of this study was to compare two techniques: A Direct Aspiration First Pass Technique (ADAPT) and Stent-retriever Assisted Vacuum-locked Extraction (SAVE) stratified by the occluded vessel.

METHODS

One hundred seventy-one patients (71 male) treated between January 2014 and September 2017 with AIS due to LVO of the anterior circulation (55 carotid T, 94 M1, 22 M2) were included. Treatment techniques were divided into two categories: ADAPT and SAVE. Primary endpoints were successful reperfusion (mTICI ≥2b), near-perfect reperfusion (mTICI ≥2c) and groin puncture to reperfusion time. Secondary endpoints were the number of device-passes, first-pass reperfusion, the frequency of emboli to new territory (ENT), clinical outcome at 90 days, and the frequency of symptomatic intracranial hemorrhage (sICH). Analysis was performed on an intention to treat basis.

RESULTS

Overall, SAVE resulted in significant higher rates of successful reperfusion (mTICI≥2b) compared to ADAPT (93.5% vs 75.0%; p = 0.006). After stratification for the occluded vessel only the carotid T remained significant with higher rates of near-perfect reperfusion (mTICI≥2c) (55.2% vs 15.4%; p = 0.025), while for successful reperfusion a trend remained (93.1% vs 65.4%; p = 0.10). Groin to reperfusion times were not significantly different. Secondary analysis revealed higher rates of first-pass successful reperfusion (59.6% vs 33.3%; p = 0.019), higher rates of first-pass near-perfect reperfusion in the carotid T (35.4% vs 16.7%; p = 0.038) and a lower number of device-passes overall (median 1 IQR 1-2 vs 2 IQR 2-3; p <  0.001) and in the carotid T (median 2 IQR 1.3 vs 3 IQR 2-5; p <  0.001) for SAVE. Clinical outcome and safety parameters were comparable between groups.

CONCLUSIONS

Embolectomy using SAVE appears superior to ADAPT, especially for carotid T occlusions with regard to reperfusion success.

Initial experience with the novel EmboTrap II clot-retrieving device for the treatment of ischaemic stroke

INTRODUCTION

We report our experience with the novel stent-type clot-retrieval device EmboTrap II for the revascularization of large artery occlusions in acute ischaemic stroke.

MATERIALS AND METHODS

Twenty-nine patients with acute ischaemic stroke due to large artery occlusion underwent mechanical thrombectomy with the new EmboTrap II in two Italian centres. Clinical, procedural and radiological data were collected. Angiographic results and neurological outcomes were analysed.

RESULTS

Only large vessel occlusions were included. Intravenous thrombolysis was administered in 72% of patients. Successful reperfusion (TICI 2b-3) was obtained in 76% of patients treated exclusively with EmboTrap II. No device-related permanent complications occurred.

CONCLUSION

In our experience, mechanical thrombectomy with EmboTrap II is safe and effective. Reperfusion rate was comparable to that obtained with other stent retrievers.

Anesthesia for endovascular treatment in anterior circulation stroke: A systematic review and meta-analysis

BACKGROUND

Endovascular treatment in patients with acute anterior circulation stroke could be performed under either conscious sedation (CS) or general anesthesia (GA). Although several studies have investigated the association between the clinical outcomes and the two anesthesia methods, consensus is lacking.

METHODS

PubMed and EMBASE searches were used to select full-text articles comparing the effects of GA and CS on functional outcome and complications in patients with anterior circulation ischemic stroke. Enrolled patients were assigned to receive endovascular treatment with CS or GA, with a primary outcome of functional independency within 90 days. Secondary outcomes included intracranial hemorrhage, all-cause mortality at 90 days, pneumonia, and intraprocedural complications.

RESULTS

Thirteen studies (3 RCTs and 10 observational studies), which included 3,857 patients (CS = 2,129, GA = 1,728), were eligible for the analysis. The overall analysis including the RCTs and observational studies demonstrated that the functional independence within 90 days occurred more frequently among patients with CS compared with GA (OR, 1.42; 95% CI, 1.05-1.92, p = 0.02); and the risk of mortality was higher with GA compared with CS; furthermore, CS was associated with lower rate of intracranial hemorrhage. In RCTs, GA was associated with increased functional independence (OR, 0.55; 95% CI, 0.34-0.89, p = 0.01) and successful reperfusion (OR, 0.51; 95% CI, 0.30-0.89, p = 0.02).

CONCLUSIONS

In the overall analysis and observational studies, CS was associated with improved functional outcomes and relatively safe for anterior ischemic stroke compared with GA. While the pooled data from RCTs suggested that GA was associated with improved outcomes. The inconsistency indicated that more large-scale RCTs are required to evaluate what factors influenced the effect of the anesthesia methods on clinical outcomes.