Stent Retriever-based Thrombectomy Research Articles

Thrombectomy With the pRESET vs Solitaire Stent Retrievers as First-Line Large Vessel Occlusion Stroke Treatment

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. To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever. 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. Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever. 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. 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. 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.

Rationale and Design of a Randomized Controlled Pilot Trial to Assess Stent Retriever Thrombectomy for Thrombus Burden Reduction in Patients with Acute Myocardial Infarction: The RETRIEVE-AMI Study

BackgroundST-elevation myocardial infarction (STEMI) is typically caused by thrombotic occlusion of a coronary artery with subsequent hypoperfusion and myocardial necrosis. In approximately half of patients with STEMI, despite successful restoration of epicardial coronary patency, downstream myocardium perfusion remains impeded. Coronary microvascular injury is one of the key mechanisms behind suboptimal myocardial perfusion and it is primarily, yet not exclusively, related to distal embolization of atherothrombotic material following recanalization of the culprit artery. Routine manual thrombus-aspiration has failed to show clinical efficacy in this scenario. This could be related with limitations in technology adopted as well as patients' selection. To this end, we set out to explore the efficacy and safety of stent retriever-assisted thrombectomy based on clot-removal device routinely used in stroke intervention. Study design and objectivesThe stent RETRIEVEr thrombectomy for thrombus burden reduction in patients with Acute Myocardial Infarction (RETRIEVE-AMI) study has been designed to establish whether stent retriever-based thrombectomy is safe and more efficacious in thrombus modification than the current standard of care: manual thrombus aspiration or stenting. The RETRIEVE-AMI trial will enrol 81 participants admitted for primary PCI for inferior STEMI. Participants will be 1:1:1 randomised to receive either standalone PCI, thrombus aspiration and PCI, or retriever-based thrombectomy and PCI. Change in thrombus burden will be assessed via optical coherence tomography imaging. A telephone follow-up at 6 months will be arranged. ConclusionsIt is anticipated by the investigators that stent retriever thrombectomy will more effectively reduce the thrombotic burden compared to current standard of care whilst being clinically safe.

Aspiration versus Stent Retriever Thrombectomy in Posterior Circulation Stroke: A Systematic Review and Meta-Analysis

Introduction: The management of posterior circulation stroke is primarily carried out by endovascular approaches including aspiration or stent retrevier thrombectomy. Existing reviews have attempted to comparatively evaluate their efficacy in terms of morbidity and mortality-related outcomes, however, with several limitations. Therefore, in this review, we attempt to address the gap in the existing literature by evaluating the comparative impact of stent retriever-based and aspiration-based thrombectomy interventions in posterior circulation stroke patients on the following parameters: overall procedure duration, recanalization time, rescue therapy usage, complication risk, and mortality risk. Methods: A systematic search of the academic literature was performed according to PRISMA guidelines across five databases. We conducted a random-effect meta-analysis to evaluate comparative outcomes, including procedural duration, time to recanalization, risk of complications, use of rescue therapy, and risk of mortality in patients with posterior circulation stroke undergoing stent retriever- and aspiration-based thrombectomies. We also performed comparative subgroup analyses to evaluate differences in outcomes between contact and manual aspiration interventions. Results: From 963 studies, we found nine eligible studies containing data on 840 patients. Meta-analysis revealed a large-to-medium size positive effect for stent retriever-based thrombectomy on overall procedure duration and recanalization compared to aspiration-based thrombectomy. Additional analysis revealed higher risk of complications and mortality in posterior circulation stroke patients undergoing stent retriever-based thrombectomy as compared to aspiration-based thrombectomy. We also observed that the use of rescue therapy was elevated in patients undergoing aspiration-based thrombectomy compared to stent retriever-based thrombectomy. Conclusion: This study provides preliminary evidence for improved morbidity and mortality outcomes in posterior circulation stroke patients undergoing aspiration-based thrombectomies as compared to stent retriever-based thrombectomy. The study also provides evidence for improved endovascular outcomes for patients undergoing aspiration-based thrombectomies. The findings from this study can have implications in developing awareness among neurosurgeons for stratifying patients to manage posterior circulation stroke according to the risks associated with aspiration and stent retriever-based thrombectomies.

03:09 PM Abstract No. 161 6-French/088 distal guide sheath access into the petrocavernous internal carotid artery to optimize mechanical thrombectomy

Modern stent retriever-based thrombectomy techniques for emergent large vessel occlusions contributed to the successful clinical trials on endovascular acute ischemic stroke intervention. Various adjunctive techniques have been described including the use of a balloon guide catheter (BGC) and/or distal access catheter (DAC) aspiration to improve first pass recanalization, complete reperfusion, and clinical outcomes. We describe a novel technique using a flexible 6French/088 distal guide sheath (DGS), defined as advancement into the petrocavernous internal carotid artery (ICA), to limit antegrade flow without a BGC and reduce the distance/tortuosity for clot extraction. We studied the relative safety and efficacy of DGS placement during standard stent retriever with DAC aspiration thrombectomy A retrospective review of 85 consecutive patients with intracranial ICA or M1-M2 middle cerebral artery (MCA) occlusions underwent stent retriever with DAC aspiration thrombectomy over a 30-month period. Patients were divided based on thrombectomy techniques, conventional stent retriever with DAC aspiration group (traditional group) and using an adjunctive DGS technique (target group). We compared recanalization efficiency (procedure time and passes), reperfusion efficacy using the modified Thrombolysis in Cerebral Ischemia (mTICI) scale, and clinical outcomes of functional independence at 90 days (modified Rankin score 0-2). We identified 36 patients (median age 69 years with NIHSS 18) in the target group and 49 patients (median age 73 years with NIHSS 20) in the traditional group (p=0.11 and 0.12 respectively). There was a trend towards lower groin to revascularization time (53 minutes vs 61 minutes) and lower mean number of thrombectomy attempts in the target group (2.2 vs 2.6), yet those trends did not reach statistical significance. The target group offered higher rates of TICI ≥2 b reperfusion (97% vs 84%; P-value 0.046) that corresponded with increased functional independence at 90 days (65% vs 38%; P=0.03). Optimizing mechanical thrombectomy techniques by advancing a DGS into the petro-cavernous ICA may confer higher reperfusion rates and improved clinical outcomes.

Introducing the New 3.5/28 Microstent Retriever for Recanalization of Distal Cerebral Arteries in Acute Stroke: Preliminary Results.

To describe our first experience using a small stent retriever specifically designed for thrombectomy in cerebral arteries with a small caliber (Acandis APERIO® 3.5/28) in patients with acute ischemic stroke. All patients with an acute ischemic stroke, who underwent endovascular recanalization using the APERIO® thrombectomy device with a diameter of 3.5mm, were identified in retrospect and included in the present analysis. Demographic and clinical data as well as data on the procedures performed were collected (patient sex, mean age, NIHSS, mRS, TICI score, and complications). Stent retriever-based thrombectomy with the Aperio® 3.5/28 alone (n = 10 vessels) or in combination with other devices (n = 13 vessels) was performed in 22 acute stroke patients with embolic occlusions of distal branches of the anterior and posterior circulations (median NIHSS = 8.5). For vessels treated with the Aperio® 3.5/28, we achieved a TICI 2b/3 reperfusion rate of 73.9%. One patient suffered a symptomatic intracerebral hemorrhage after thrombectomy; otherwise, no procedure-related complications were seen. Our data suggest that mechanical thrombectomy of distal cerebral artery occlusions with the Aperio® 3.5/28 is feasible and in general safe, thus offering a promising option for endovascular stroke therapy. However, multicentric studies with larger patient cohorts are necessary to evaluate the clinical benefit.

Endovascular Stroke Treatment of Patients Over 80 Years Old: Cumulative Evidence from the “Real World”

Evidence on stent retriever-based thrombectomy (SRT) efficacy in elderly patients is controversial. This study aimed to analyze safety and efficacy outcomes in octogenarians submitted to SRT. Analysis was based on a prospective observational registry of patients with stroke because of anterior circulation large-vessel occlusion treated with SRT at our center between January 2015 and September 2016. Patients were dichotomized into 2 age groups: ≤80 and >80 years old. Outcomes at 90 days were assessed: "excellent outcome" (a modified Rankin scale [mRs] score of 0-1) and "good outcome" (a mRs score of 0-2). A total of 141 patients were included: 35 (24.8%) >80 years old and 106 (71.2%) ≤80 years old; 43.4% of patients in the younger group and 25.7% of patients in the older group achieved an "excellent outcome." A "good outcome" was achieved in 65.1% of patients in the younger group, and 60% of patients in the older group; crude odds ratio (OR) for "excellent outcome" was 0.452 (P = .067). Crude OR for "good outcome" was 0.804 (P = .587). After adjusting for gender, National Institutes of Health Stroke Scale score at admission, Alberta Stroke Program Early CT Score, and thrombolysis, the OR was 0.450 (P = .100) and 1.217 (P = .686) for "excellent" and "good" outcomes, respectively. In this cohort, 60% of elderly patients regained functional independence at 3 months after SRT. Although age may be a prognostic factor, patients should not be excluded from SRT based on age criteria.

Effect of Baseline Characteristics on the Outcome of Stent Retriever-Based Thrombectomy in Acute Basilar Artery Occlusions: A Single-Center Experience and Pooled Data Analysis.

To explore the association of baseline characteristics and the outcome of patients with acute basilar artery occlusion (BAO) after stent retriever-based thrombectomy (SRT). Clinical and imaging information of consecutive SRT-treated patients with BAO from a comprehensive stroke center and up-to-date literature were reviewed respectively. The impact of baseline variables toward favorable outcome was evaluated using subgroup analysis and odds ratio (OR) extracted from published data together with single-center records using pooled analysis. Nineteen cases from our center and 15 published studies involving 487 cases were included. Estimated pooled favorable outcome rate was 0.3746 (95% confidence interval [CI], 0.3165-0.4327), mortality was 0.2950 (95% CI, 0.2390-0.3510). Pooled estimates showed that successful reperfusion (modified thrombolysis in cerebral ischemia scale 2b or 3) gained by SRT alone was 0.7317 (95% CI, 0.6532-0.8102) and final successful reperfusion rate with or without additional reperfusion procedures was 0.8834 (95% CI, 0.8279-0.9390). Univariate analysis indicated that patients with successful reperfusion (OR, 2.05; P= 0.05), distal segment occlusion (OR, 2.03; P= 0.03), and cardioembolus origin (OR, 2.13; P=0.01) were more likely to have favorable outcome (modified Rankin Scale score ≤2 at 3 months). Study series that applied intra-arterial thrombolysis, angioplasty, or stenting as rescuing therapy had higher successful reperfusion rate but they did not show a higher rate of favorable outcome. SRT with or without additional treatment appeared to be effective for the treatment of BAO. Successful reperfusion, distal segment occlusion, and cardiac embolism were associated with favorable outcome. The overall benefit of lesions requiring additional reperfusion therapy was unclear.

Aspiration thrombectomy in clinical routine interventional stroke treatment

The aim of our study was the technical evaluation of afirst pass approach of primary thrombus aspiration (AST) in patients with emergency large intracerebral vessel occlusions (ELVO) under routine clinical conditions. We collected procedural and clinical data of 104 patients who underwent mechanical thrombectomy due to ELVO between June 2014 and January 2016 with intentional first-line thrombus aspiration. Procedures were conducted due to occlusions of the distal internal carotid artery, middle cerebral artery, anterior cerebral artery, basilar artery and posterior cerebral artery and were performed with the patient under either conscious sedation or general anesthesia. If the AST technique failed completely or to some extent, stent retriever-based thrombectomy (SRT) was performed. As astand-alone method AST was successful in achieving TICI (Thrombolysis in Cerebral Infarction) score 2b or3 results in 29cases (27.8%). After additional use of SRT successful recanalization was achieved in atotal of 95cases (91.3%, p= 0.048). If AST was performed exclusively, median procedure time until TICI2b/3 was 15 min, in cases of combined procedures 35 min (p= 0.001). Subarachnoid hemorrhage (SAH) after thrombectomy appeared only if additional SRT was performed (12.0%) and not in cases of AST maneuvers alone (p= 0.09). When used as afirst pass attempt AST is afast and safe approach for patients suffering from stroke due to ELVO. Nonetheless, early conversion to SRT is needed in most cases and leads to overall excellent procedural results with low complication rates.

Continuous aspiration prior to intracranial vascular embolectomy (CAPTIVE): a technique which improves outcomes

BackgroundModern stent retriever-based embolectomy for patients with emergent large vessel occlusion improves outcomes. Techniques aimed at achieving higher rates of complete recanalization would benefit patients.ObjectiveTo evaluate the clinical impact of...

Stent Retriever-Based Thrombectomy in Octogenarians

Background and Aims: Stent retriever-based thrombectomy (SRT) may be beneficial in patients with large hemispheric stroke. Previous studies concluded that favorable outcomes are far less frequent after endovascular therapy in older patients but have not explored outcomes in the era of newer-generation stent retrievers. Materials and Methods: Consecutive patients with large hemispheric stroke treated with SRT were included. We compared neurological and functional outcomes between patients younger and older than 80. Results: We included 16 patients older than 80 (22.5%, mean age 84.1 ± 4.4, 56% females) and compared them to 55 patients that were younger than 80 (77.5%, mean age 63.1 ± 12.5, 51% females). Risk factor profile, admission neurological severity, stroke etiology and procedure-related variables including excellent target vessel recanalization did not differ between the groups. Favorable outcome at 90 days (modified Rankin score ≤2) was more common in younger patients (77 vs. 23%; p = 0.031). In contrast, mortality rates were higher in octogenarians (40 vs. 7%; p = 0.01). Logistic regression analysis adjusting for neurological severity and collateral state identified age over 80 (odds ratio, OR 0.15, 95% CI 0.03-0.75; p = 0.02) and reperfusion state (OR 7.4, 95% CI 1.1-49.9; p = 0.04) as significant modifiers of favorable outcome. Similarly, age over 80 was identified as a positive predictor of mortality (OR 8.1, 95% CI 1.8-36.7; p = 0.007). Conclusions: Octogenarians have higher chances of mortality and lower probability of achieving functional independence even after SRT. Nevertheless, because some elderly patients do achieve favorable outcomes, the cost-effectiveness of SRT in this population needs to be further studied.

Mechanical Thrombectomy of M2-Occlusion

There is growing evidence for the efficacy of mechanical thrombectomy in acute stroke patients with large-vessel occlusions in the anterior circulation. Although distal occlusions of the middle cerebral artery (MCA) can cause severe clinical symptoms, endovascular therapy is not considered here as the first choice. The aim of our study was to prove the efficacy and safety of mechanical thrombectomy for distal occlusion types in the anterior circulation (M2-segment). Stentretriever-based thrombectomy was performed in 119 patients with acute MCA occlusions between October 2011 and April 2013: 104 (87.4%) were M1- and 15 (12.6%) M2-occlusions. These groups were compared with regard to recanalization success, periprocedural complications, hemorrhage, and modified Rankin Scale (mRS) at 90 days. Thrombolysis in cerebral infarction 2b/3 reperfusion was more frequent in M2- than in M1-occlusions (93.3% versus 76.0%; P = .186). There was no significant difference in the mean National Institutes of Health Stroke Scale between the M1- and the M2-group both at admission and at discharge (16.18 ± 7.30 versus 13.73 ± 8.30, P = .235; 9.36 ± 8.60 versus 7.43 ± 9.84, P = .446). A good clinical outcome (mRS 0-2) at 3 months was more frequent in the M2-group (60% versus 43.3%; P = .273) and mortality was higher in the M1-group (21.2% versus 6.7%; P = .297). There were 3 periprocedural complications in the M1- and none in the M2-group. Endovascular treatment of M2-occlusions in severely affected patients is not associated with a higher procedural risk or postprocedural hemorrhage. Compared with M1-occlusions, there was a greater chance for a good angiographic and clinical result in our case series. Therefore, stentretriever-based thrombectomy should also be considered for patients with severe symptoms because of an acute M2-occlusion.

La pyélonéphrite emphysémateuse

To explore the association of baseline characteristics and the outcome of patients with acute basilar artery occlusion (BAO) after stent retriever–based thrombectomy (SRT).Clinical and imaging information of consecutive SRT-treated patients with BAO from a comprehensive stroke center and up-to-date literature were reviewed respectively. The impact of baseline variables toward favorable outcome was evaluated using subgroup analysis and odds ratio (OR) extracted from published data together with single-center records using pooled analysis.Nineteen cases from our center and 15 published studies involving 487 cases were included. Estimated pooled favorable outcome rate was 0.3746 (95% confidence interval [CI], 0.3165–0.4327), mortality was 0.2950 (95% CI, 0.2390–0.3510). Pooled estimates showed that successful reperfusion (modified thrombolysis in cerebral ischemia scale 2b or 3) gained by SRT alone was 0.7317 (95% CI, 0.6532–0.8102) and final successful reperfusion rate with or without additional reperfusion procedures was 0.8834 (95% CI, 0.8279–0.9390). Univariate analysis indicated that patients with successful reperfusion (OR, 2.05; P = 0.05), distal segment occlusion (OR, 2.03; P = 0.03), and cardioembolus origin (OR, 2.13; P = 0.01) were more likely to have favorable outcome (modified Rankin Scale score ≤2 at 3 months). Study series that applied intra-arterial thrombolysis, angioplasty, or stenting as rescuing therapy had higher successful reperfusion rate but they did not show a higher rate of favorable outcome.SRT with or without additional treatment appeared to be effective for the treatment of BAO. Successful reperfusion, distal segment occlusion, and cardiac embolism were associated with favorable outcome. The overall benefit of lesions requiring additional reperfusion therapy was unclear.