scholarly journals Biomechanics and hemodynamics of stent-retrievers

2020 ◽  
Vol 40 (12) ◽  
pp. 2350-2365
Author(s):  
Anna Luisa Kühn ◽  
Zeynep Vardar ◽  
Afif Kraitem ◽  
Robert M King ◽  
Vania Anagnostakou ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Randomized Clinical Trials ◽  
Intravenous Thrombolysis ◽  
Stent Retriever ◽  
Large Artery ◽  
Level Of Evidence ◽  
Standard Medical Therapy ◽  
Stent Retrievers

In 2015, multiple randomized clinical trials showed an unparalleled treatment benefit of stent-retriever thrombectomy as compared to standard medical therapy for the treatment of a large artery occlusion causing acute ischemic stroke. A short time later, the HERMES collaborators presented the patient-level pooled analysis of five randomized clinical trials, establishing class 1, level of evidence A for stent-retriever thrombectomy, in combination with intravenous thrombolysis when indicated to treat ischemic stroke. In the years following, evidence continues to mount for expanded use of this therapy for a broader category of patients. The enabling technology that changed the tide to support endovascular treatment of acute ischemic stroke is the stent-retriever. This review summarizes the history of intra-arterial treatment of stroke, introduces the biomechanics of embolus extraction with stent-retrievers, describes technical aspects of the intervention, provides a description of hemodynamic implications of stent-retriever embolectomy, and proposes future directions for a more comprehensive, multi-modal endovascular approach for the treatment of acute ischemic stroke.

scholarly journals Endovascular Treatment for Acute Ischemic Stroke: Updates and Future Implications

2015 ◽  
Vol 4 (1-2) ◽  
pp. 43-47 ◽  
Author(s):  
Jie Gao ◽  
Qiliang Dai ◽  
Xinfeng Liu
Keyword(s):  
Ischemic Stroke ◽  
Endovascular Treatment ◽  
Acute Ischemic Stroke ◽  
Randomized Clinical Trials ◽  
Intravenous Thrombolysis ◽  
Professional Organizations ◽  
Infarct Core ◽  
The Past ◽  
Proximal Occlusion ◽  
Positive Results

Stroke constitutes the primary cause of acquired disability in adults and is a second leading cause of death worldwide. The low recanalization rate after intravenous thrombolysis calls for an alternate therapy for acute ischemic stroke. The methodology for endovascular treatment has evolved greatly over the past two decades. The past 6 months have seen great progress in this area, with several randomized clinical trials all proving the efficacy and safety of endovascular treatment. Three key factors are important for good functional outcome after endovascular treatment: fast imaging to prove proximal occlusion and to exclude large infarct core, using mainly the stent retriever thrombectomy devices and establishing an efficient workflow to achieve fast reperfusion. Although positive results of RCTs are encouraging and bring what is urgently needed in the field, transforming these positive results into clinical practice will be both a challenge and opportunity of the next 5 years. It will need hard work, leadership and cooperation of all members involved in the chain of treating a stroke patient. In the wake of these positive trials, hospitals and professional organizations are working together to save every minute when fighting against this devastating disease.

Thrombectomy of calcified emboli in stroke. Does histology of thrombi influence the effectiveness of thrombectomy?

2017 ◽  
Vol 10 (4) ◽  
pp. 345-350 ◽  
Author(s):  
Tomas Dobrocky ◽  
Eike Piechowiak ◽  
Alessandro Cianfoni ◽  
Felix Zibold ◽  
Luca Roccatagliata ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Ischemic Stroke ◽  
Clinical Practice ◽  
Adverse Events ◽  
Acute Ischemic Stroke ◽  
Endovascular Therapy ◽  
Stent Retriever ◽  
Complication Rates ◽  
Peripheral Vessel ◽  
Stent Retrievers

Background and purposeThrombus composition has been postulated to affect the success of endovascular therapy. Calcified clots are composed of large amounts of calcium phosphate which influences their mechanical properties and may serve as a model for testing this hypothesis. The aim of this study was to evaluate the recanalization and complication rates of calcified thromboemboli in patients with acute ischemic stroke who underwent thrombectomy.Material and methodsA retrospective analysis was performed of all calcified intracranial thromboemboli in patients suffering an acute ischemic stroke, referred for endovascular therapy at two centers between January 2013 and July 2016.ResultsEight patients with a calcified intracranial clot underwent stent retriever thrombectomy (five women; mean age 80 years). Mean clot attenuation was 305 HU (range 150–640 HU). Successful reperfusion defined, as Thrombolysis in Cerebral Infarction grade 2b–3 was achieved in only one patient (12.5%). Two periprocedural adverse events occurred: one peripheral vessel perforation which was coiled and one inadvertent stent retriever detachment due to fracture of the stent retriever wire.ConclusionStent retriever thrombectomy of calcified thromboemboli seems less effective than with other types of clots. Different mechanical properties of calcified clots may render them stiffer and less accessible for stent retrievers. When faced with a calcified intracranial thromboembolus in clinical practice, a more contained approach may be warranted in view of low recanalization rates, and the potential for periprocedural adverse events.

scholarly journals Correlation between clot density and recanalization success or stroke etiology in acute ischemic stroke patients

2017 ◽  
Vol 23 (3) ◽  
pp. 274-278 ◽  
Author(s):  
Manoj Jagani ◽  
David F Kallmes ◽  
Waleed Brinjikji
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Region Of Interest ◽  
Hounsfield Unit ◽  
Stent Retriever ◽  
Large Artery ◽  
Stroke Etiology ◽  
Significant Difference ◽  
The Mean ◽  
Axial Slice

Background Predicting recanalization success for patients undergoing endovascular treatment for acute ischemic stroke is of significant interest. Studies have previously correlated the success of recanalization with the density of the clot. We evaluated clot density and its relationship to revascularization success and stroke etiology. Methods We conducted a retrospective review of 118 patients undergoing intra-arterial therapy for acute ischemic stroke. Mean and maximum thrombus density was measured by drawing a circular region of interest on an axial slice of a non-contrast computed tomography scan. T-tests were used to compare clot density to recanalization success or to stroke etiology, namely large artery atherosclerosis and cardioembolism. Recanalization success was compared in four device groups: aspiration, stent retriever, aspiration and stent retriever, and all other. Results There was no significant difference in the mean clot density in patients with successful ( n = 80) versus unsuccessful recanalization ( n = 38, 50.1 ± 7.4 Hounsfield unit (HU) vs. 53 ± 12.7 HU; P = 0.17). Comparing the large artery thromboembolism ( n = 35) to the cardioembolic etiology group ( n = 56), there was no significant difference in mean clot density (51.5 ± 7.7 HU vs. 49.7 ± 8.5 HU; P = 0.31). A subgroup analysis of middle cerebral artery occlusions ( n = 65) showed similar, non-statistically significant differences between groups. There was no difference in the rate of recanalization success in patients with a mean clot density greater than 50 HU or less than 50 HU in each of the four device groups. Conclusions There was no relationship between clot density and revascularization success or stroke etiology in our study. More research is needed to determine if clot density can predict recanalization rates or indicate etiology.

scholarly journals Comparison of non–stent retriever and stent retriever mechanical thrombectomy devices for the endovascular treatment of acute ischemic stroke

2017 ◽  
Vol 126 (4) ◽  
pp. 1123-1130 ◽  
Author(s):  
Kate A. Hentschel ◽  
Badih Daou ◽  
Nohra Chalouhi ◽  
Robert M. Starke ◽  
Shannon Clark ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Mechanical Thrombectomy ◽  
Independent Predictor ◽  
Univariate Analysis ◽  
Standard Of Care ◽  
Stent Retriever ◽  
Radiographic Outcomes ◽  
Scale Scores ◽  
Stent Retrievers

OBJECTIVE Mechanical thrombectomy is standard of care for the treatment of acute ischemic stroke. However, limited data are available from assessment of outcomes of FDA-approved devices. The objective of this study is to compare clinical outcomes, efficacy, and safety of non–stent retriever and stent retriever thrombectomy devices. METHODS Between January 2008 and June 2014, 166 patients treated at Jefferson Hospital for Neuroscience for acute ischemic stroke with mechanical thrombectomy using Merci, Penumbra, Solitaire, or Trevo devices were retrospectively reviewed. Primary outcomes included 90-day modified Rankin Scale (mRS) score, recanalization rate (thrombolysis in cerebral infarction [TICI score]), and incidence of symptomatic intracranial hemorrhages (ICHs). Univariate analysis and multivariate logistic regression determined predictors of mRS Score 3–6, mortality, and TICI Score 3. RESULTS A total of 99 patients were treated with non–stent retriever devices (Merci and Penumbra) and 67 with stent retrievers (Solitaire and Trevo). Stent retrievers yielded lower 90-day NIH Stroke Scale scores and higher rates of 90-day mRS scores ≤ 2 (22.54% [non–stent retriever] vs 61.67% [stent retriever]; p < 0.001), TICI Score 2b–3 recanalization rates (79.80% [non–stent retriever] vs 97.01% [stent retriever]; p < 0.001), percentage of parenchyma salvaged, and discharge rates to home/rehabilitation. The overall incidence of ICH was also significantly lower (40.40% [non–stent retriever] vs 13.43% [stent retriever]; p = 0.002), with a trend toward lower 90-day mortality. Use of non–stent retriever devices was an independent predictor of mRS Scores 3–6 (p = 0.002), while use of stent retrievers was an independent predictor of TICI Score 3 (p < 0.001). CONCLUSIONS Stent retriever mechanical thrombectomy devices achieve higher recanalization rates than non–stent retriever devices in acute ischemic stroke with improved clinical and radiographic outcomes and safety.

scholarly journals “Y-stent retriever”: a new rescue technique for refractory large-vessel occlusions?

2018 ◽  
Vol 128 (5) ◽  
pp. 1349-1353 ◽  
Author(s):  
Roberto Crosa ◽  
Alejandro M. Spiotta ◽  
Matías Negrotto ◽  
Alejandra Jaume ◽  
Walter Casagrande
Keyword(s):  
Ischemic Stroke ◽  
Mechanical Thrombectomy ◽  
Stent Retriever ◽  
Large Vessel ◽  
Positive Trial ◽  
Large Artery ◽  
Anterior Circulation ◽  
Vessel Occlusion ◽  
Flow Restoration ◽  
Stent Retrievers

Long-awaited positive trial data have shown the efficacy of endovascular treatment in patients with ischemic stroke who arrive at the hospital within the first 6 hours with large-vessel occlusion of the anterior circulation. With the introduction of stent retrievers (SRs) for mechanical thrombectomy, efficient and safe large-artery recanalization treatment can be achieved. However, sometimes there are patients who do not attain complete flow restoration following attempts with traditional maneuvers. The authors present the case of a 57-year-old man with acute ischemic stroke due to an M1 embolus that extended into both M2 trunks. This patient was successfully treated with an innovative technique in which a Solitaire SR (Covidien) and a Catch SR (Balt) were used in a “Y” configuration, for which the authors coined the term “Y-stent retriever.”

Direct endovascular treatment versus bridging therapy in patients with acute ischemic stroke eligible for intravenous thrombolysis: systematic review and meta-analysis

2021 ◽  
pp. neurintsurg-2021-017928
Author(s):  
Jian Zhang ◽  
Shijian Chen ◽  
Shengliang Shi ◽  
Yueling Zhang ◽  
Deyan Kong ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Intracranial Hemorrhage ◽  
Observational Studies ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Intravenous Thrombolysis ◽  
Cochrane Library ◽  
Bridging Therapy ◽  
Excellent Outcome

ObjectiveIn this review and meta-analysis we sought to compare the efficacy and safety of direct endovascular thrombectomy (EVT) and bridging therapy for intravenous thrombolysis (IVT)-eligible patients with acute ischemic stroke caused by large vessel occlusions (AIS-LVO).MethodsWe searched Medline, Embase, and the Cochrane Library for published randomized clinical trials (RCTs) and observational studies providing outcomes of patients with IVT-eligible AIS-LVO who have undergone EVT with or without IVT. The primary outcome was the proportion of patients achieving a modified Rankin Scale (mRS) score of 0–2 at 90 days. The secondary outcomes included the rates of (1) an excellent outcome defined as an mRS score of 0 or 1 at 90 days, (2) mortality at 90 days, (3) symptomatic intracranial hemorrhage (sICH), (4) any type of intracranial hemorrhage (ICH), (5) successful recanalization, and (6) clot migration.ResultsWe included three RCTs and six observational studies (4 of which were propensity score-adjusted studies) with a total of 3133 patients. In unadjusted and adjusted analyses, no differences in the rates of mRS scores 0–2, mRS scores 0–1, mortality at 90 days, sICH or successful recanalization were detected between patients with AIS-LVO who underwent direct EVT or bridging therapy. The patients treated with direct EVT had a lower risk ratio for any type of ICH and clot migration than did the patients treated with bridging therapy.ConclusionCompared with bridging therapy, direct EVT may be equally effective and yield a lower rate of ICH and clot migration in patients with AIS.Trail registration numberPROSPERO: CRD42021236691.

scholarly journals Endovascular thrombectomy without versus with intravenous thrombolysis in acute ischemic stroke: a non-inferiority meta-analysis of randomized clinical trials

2021 ◽  
pp. neurintsurg-2021-017667
Author(s):  
Chun-Hsien Lin ◽  
Jeffrey L Saver ◽  
Bruce Ovbiagele ◽  
Wen-Yi Huang ◽  
Meng Lee
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Randomized Trials ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Intravenous Thrombolysis ◽  
Functional Independence ◽  
Risk Difference ◽  
Endovascular Thrombectomy ◽  
Symptomatic Intracranial Hemorrhage

ObjectiveTo conduct a meta-analysis of randomized trials to comprehensively compare the effect of endovascular thrombectomy (EVT) versus intravenous thrombolysis (IVT) plus EVT on functional independence (modified Rankin Scale (mRS) 0–2) after acute ischemic stroke due to large vessel occlusions (AIS-LVO).MethodsWe searched Pubmed, EMBASE, CENTRAL, and clinicaltrials.gov from January 2000 to February 2021 and abstracts presented at the International Stroke Conference in March 2021 to identify trials comparing EVT alone versus IVT plus EVT in AIS-LVO. Five non-inferiority margins established in the literature were assessed: −15%, −10%, −6.5%, −5%, and −1.3% for the risk difference for functional independence at 90 days.ResultsFour trials met the selection criteria, enrolling 1633 individuals, with 817 participants randomly assigned to EVT alone and 816 to IVT plus EVT. Crude cumulative rates of 90-day functional independence were 46.0% with EVT alone versus 45.5% with IVT plus EVT. Pooled results showed the risk difference of functional independence was 1% (95% CI −4% to 5%) between EVT alone versus IVT plus EVT. The lower 95% CI bound of −4% fell within the non-inferiority margins of −15%, −10%, −6.5%, and −5%, but not −1.3%. Pooled results also showed the risk difference between EVT alone versus IVT plus EVT was 1% (95% CI −3% to 5%) for mRS 0–1, and 1% (95% CI −1% to 3%) for symptomatic intracranial hemorrhage.ConclusionsThis meta-analysis suggests that EVT alone is non-inferior to IVT plus EVT for several, but not the most stringent, non-inferiority margins.

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