A retrieval thrombectomy technique with the Solitaire stent in a large cerebral artery occlusion

The effect of distal aspiration catheter position on collateral flow in mechanical thrombectomy - an in vitro study

INTRODUCTION

Endovascular mechanical thrombectomy for ischaemic stroke is one of the most effective treatments. Despite the devices and techniques that have been developed, thrombi are not always successfully retrieved. The incidence of futile reperfusion after successful clot retrieval also remains a major concern. We hypothesise that simply placing an aspiration catheter in the system compromises collateral flow which may have an impact on functional outcomes.

METHODS

An in vitro study was conducted using a physical pulsatile flow model designed in glass to mimic the anterior cerebral circulation with middle cerebral artery M1 segment occlusion. A 5Fr aspiration catheter was positioned at the supra-clinoid internal carotid (SC-ICA), carotid terminus (T-ICA) and M1. For each catheter position, the flow rate through the model's anterior cerebral (ACA) and posterior communicating (PCOM) arteries was measured (no aspiration applied).

RESULTS

Our results showed significant mean percentage flow reductions in the ACA and PCOM with the catheter positioned at the SC-ICA (PCOM 59.14% ± 0.93, ACA 59.52% ± 0.82, p < 0.001), T-ICA (PCOM 81.54% ± 0.55, ACA 85.65% ± 1.54) and M1 (PCOM 75.79% ± 0.98, ACA 84.20% ± 0.43) (Mann-Whitney U Test, p < 0.001).

CONCLUSION

These results indicate a significant reduction in collateral flow following the insertion of a wide bore catheter in an in vitro model. In a clinical setting, this could have an impact on patient outcome, particularly in prolonged procedures and those requiring several passes to achieve recanalisation.

Mechanical thrombectomy reduces the gap in treatment outcomes of ischemic stroke between hospital levels of care: analysis of a Korean nationwide data

Background

Mechanical thrombectomy (MT) of ischemic stroke was demonstrated to be effective in clinical trials and was reported to have favorable outcomes in real clinical settings since 2015. We aimed to determine the national trends of MT and compare the outcomes between the different levels of treating hospital.

Methods

We obtained data from the nationwide database from 2008 to 2017. Patients with ischemic stroke who received MT were identified using the International Classification of Disease Codes. Good outcome was defined as discharge to home, and a poor outcome was defined as cerebral hemorrhage, physical disability, or death. The study period was divided into three (off-label MT, transitional, MT period). Hospital groups where MT was performed were divided into tertiary and non-tertiary hospitals.

Results

In MT period, 47.0% of the MT procedures were performed in non-tertiary hospitals compared with 36.1% in off-label MT period. Comparison of the 3-month mortality between patients who were treated in tertiary vs. non-tertiary hospitals revealed significant lower mortality in tertiary hospital through all period. The incidence of cerebral hemorrhage and physical disability did not differ between hospital groups. However, the percentage of patients discharged home was 41.4% for tertiary hospitals and 42.4% for non-tertiary hospitals, which was not statistically different in MT period (P=0.4671).

Conclusions

Analysis of the nationwide data confirmed that the extent of increase in MT was higher in non-tertiary hospitals than tertiary hospitals. In addition, no significant difference was revealed in the number of favorable clinical outcome between the hospital groups during MT period.

Mass Spectrometry-Based Proteomic Profiling of Thrombotic Material Obtained by Endovascular Thrombectomy in Patients with Ischemic Stroke

Thrombotic material retrieved from acute ischemic stroke (AIS) patients represents a valuable source of biological information. In this study, we have developed a clinical proteomics workflow to characterize the protein cargo of thrombi derived from AIS patients. To analyze the thrombus proteome in a large-scale format, we developed a workflow that combines the isolation of thrombus by endovascular thrombectomy and peptide chromatographic fractionation coupled to mass-spectrometry. Using this workflow, we have characterized a specific proteomic expression profile derived from four AIS patients included in this study. Around 1600 protein species were unambiguously identified in the analyzed material. Functional bioinformatics analyses were performed, emphasizing a clustering of proteins with immunological functions as well as cardiopathy-related proteins with blood-cell dependent functions and peripheral vascular processes. In addition, we established a reference proteomic fingerprint of 341 proteins commonly detected in all patients. Protein interactome network of this subproteome revealed protein clusters involved in the interaction of fibronectin with 14-3-3 proteins, TGFβ signaling, and TCP complex network. Taken together, our data contributes to the repertoire of the human thrombus proteome, serving as a reference library to increase our knowledge about the molecular basis of thrombus derived from AIS patients, paving the way toward the establishment of a quantitative approach necessary to detect and characterize potential novel biomarkers in the stroke field.

Experience with A Direct Aspiration First Pass Technique (ADAPT) for Thrombectomy in Distal Cerebral Artery Occlusions Causing Acute Ischemic Stroke

BACKGROUND

Thromboembolic occlusion of distal branches in anterior and posterior circulation may produce severe clinical deficits. A Direct Aspiration at first Pass Technique (ADAPT) is a simple, fast method for achieving good angiographic and clinical outcomes using large-bore catheters in large vessel occlusions. We present our results using ADAPT with distal cerebral artery occlusions.

METHODS

ADAPT was used to treat 35 patients (14 women, 21 men; average age 65.5 years ± 12.6) with acute ischemic stroke with thrombus in the distal middle cerebral artery, anterior cerebral artery, or posterior cerebral artery. Patients presented with a mean National Institutes of Health Stroke Scale score of 14.1 ± 6.9; 15 patients received intravenous tissue plasminogen activator. Mean time from onset to puncture was 7.1 hours ± 5.1. Of patients, 28 (80%) presented with isolated M2 segment occlusions, 1 (2.9%) presented with isolated A3 segment occlusion, and 6 (17.1%) presented with tandem occlusions.

RESULTS

Mean time to recanalization was 35.7 minutes ± 26.4. A thrombolysis in cerebral infarction grade 2B or better was achieved in 34 patients (97.1%), with 15 achieving a thrombolysis in cerebral infarction 3. Aspiration alone was successful in 26 cases (77.1%), whereas 7 (20%) required additional techniques. A 90-day modified Rankin Scale score was available in 32 patients; 59.4% had a 90-day score of 0-2. No patients had a modified Rankin Scale score of 6.

CONCLUSIONS

Acute distal anterior circulation thromboembolic occlusions may be treated safely with intraarterial thrombectomy. Prior studies have demonstrated the success of ADAPT in proximal large vessel occlusions. This series suggests that ADAPT is an effective, safe method for performing thrombectomy in distal branches of anterior and posterior circulation.

Quantitative assessment of device-clot interaction for stent retriever thrombectomy

PURPOSE

Rapid revascularization in emergent large vessel occlusion with endovascular embolectomy has proven clinical benefit. We sought to measure device-clot interaction as a potential mechanism for efficient embolectomy.

METHODS

Two different radiopaque clot models were injected to create a middle cerebral artery occlusion in a patient-specific vascular phantom. A radiopaque stent retriever was deployed within the clot by unsheathing the device or a combination of unsheathing followed by pushing the device (n=8/group). High-resolution cone beam CT was performed immediately after device deployment and repeated after 5 min. An image processing pipeline was created to quantitatively evaluate the volume of clot that integrates with the stent, termed the clot integration factor (CIF).

RESULTS

The CIF was significantly different for the two deployment variations when the device engaged the hard clot (p=0.041), but not the soft clot (p=0.764). In the hard clot, CIF increased significantly between post-deployment and final imaging datasets when using the pushing technique (p=0.019), but not when using the unsheathing technique (p=0.067). When we investigated the effect of time on CIF in the different clot models disregarding the technique, the CIF was significantly increased in the final dataset relative to the post-deployment dataset in both clot models (p=0.004-0.007).

CONCLUSIONS

This study demonstrates in an in vitro system the benefit of pushing the Trevo stent during device delivery in hard clot to enhance integration. Regardless of delivery technique, clot-device integration increased in both clot models by waiting 5 min.

Endovascular Treatment for Acute Ischemic Stroke Patients over 80 Years of Age

Objective

We evaluated the effect of endovascular treatment (EVT) for acute ischemic stroke in patients over 80 years of age.

Materials and Methods

The records of 156 acute stroke patients aged over 80 years who were considered as candidates for EVT were analyzed. Fifty-six patients (35.9%, EVT group) underwent EVT and 100 patients (64.1%, non-EVT group) did not. Outcomes, in terms of functional outcomes and rates of symptomatic hemorrhage, in-hospital morbidity and mortality, were compared between groups. Each comparison was adjusted for age, time from onset, initial National Institute of Health Stroke Scale, and pre-stroke modified Rankin Scale (mRS).

Results

More patients in the EVT group achieved good outcomes (mRS score of 0-2) at 3 months (35.7% vs. 11.0%, adjusted odds ratio [OR] 4.779 [95% confidence interval 1.972-11.579], p = 0.001) and 12 months (35.7% vs. 14.0%, adjusted OR 3.705 [1.574-8.722], p = 0.003) after stroke. During admission, rates of hospital-acquired infection including pneumonia (12.5% vs. 29.0%, adjusted OR 0.262 [0.098-0.703], p = 0.008) and urinary tract infection (16.0% vs. 34.0%, adjusted OR 0.256 [0.099-0.657], p = 0.005) were significantly lower in the EVT group. More symptomatic hemorrhages (10.7% vs. 2.0%, adjusted OR 6.859 [1.139-41.317], p = 0.036) occurred in the EVT group, but no significant difference was observed in in-hospital mortality rate (12.5% vs. 8.0%, adjusted OR 1.380 [0.408-4.664], p = 0.604).

Conclusion

EVT improved functional outcome and reduced the risk of hospital-acquired infections in acute stroke patients over 80 years of age without increasing the risk of in-hospital mortality, although symptomatic hemorrhage occurred more frequently after EVT.

Recanalization and Reperfusion Therapies of Acute Ischemic Stroke: What have We Learned, What are the Major Research Questions, and Where are We Headed?

Two placebo-controlled trials have shown that early administration of intravenous recombinant tissue plasminogen activator (rt-PA) after ischemic stroke improves outcomes up to 4.5 h after symptoms onset; however, six other trials contradict these results. We also know from analysis of the pooled data that benefits from treatment decrease as time from stroke onset to start of treatment increases. In addition to time, another important factor is patient selection through multimodal imaging, combining data from artery status, and salvageable tissue measures. Nonetheless, at the present time randomized controlled trials (RCTs) cannot demonstrate any beneficial outcomes for neuroimaging mismatch selection after 4.5 h from symptoms onset. By focusing on cases of large arterial occlusion, we know that recanalization is crucial, so endovascular treatment is an approach of interest. The use of intra-arterial thrombolysis was tested in two small RCTs that demonstrated clear benefits in terms of higher recanalization and also in clinical outcomes. But a new paradigm of stroke treatment may have begun with mechanical thrombectomy. In this field, Merci devices have been overtaken by fully deployed closed-cell self-expanding stents (stent-retrievers or “stent-trievers”). However, despite the high rate of recanalization achieved with stent-retrievers compared with other recanalization treatments, the use of these devices cannot clearly demonstrate better outcomes. Thus, futile recanalization occurs when successful recanalization fails to improve functional outcome. Recently, three RCTs, namely synthesis, IMS-III, and MR-rescue, have not been demonstrated any clear benefit for endovascular treatment. Most likely, these trials were not adequately designed to prove the superiority of endovascular treatment because they did not use optimal target populations, vascular status was not evaluated in all patients, relatively high rates of patients did not have enough mismatch, time from baseline neuroimaging to recanalization were too long or the devices used are now obsolete relative to stent-retrievers. Several RCTs currently underway are trying to determine whether bridging therapy is more effective than intravenous treatment and if mechanical thrombectomy is more effective than best medical treatment in patients ineligible for intravenous thrombolysis.

Endovascular treatment of severe acute basilar artery occlusion

Severe acute basilar artery occlusion (BAO) has a high mortality rate but as yet no effective treatment has been developed. This study aimed to evaluate the feasibility and safety of combined mechanical thrombectomy, intra-arterial thrombolysis, and emergent stent placement for patients with severe acute BAO. Eighteen patients who were unconscious after confirmed onset of BAO and who were given arterial interventional treatment from March 2011 to June 2013 at our department were included in this study. The mean age was 59.56 years (range: 31-76 years) and patients were in a critical physical condition upon admission, and had a mean National Institutes of Health Stroke Scale (NIHSS) score of 25.94 (range: 18-35). All patients were treated with mechanical thrombectomy, 10 of whom received mechanical thrombectomy only. Of the others, eight were also treated with intra-arterial thrombolysis, three were treated with emergent stent placement, and 17 were treated with recanalization with an achieved recanalized rate of 94.4%. The average number of passes through the stent was 1.5 (range: 1-3) and five patients died (27.8%). Thirteen patients survived, and the mean NIHSS score was 6.54 (range: 0-16). Seven patients showed a modified Rankin Scale score ⩽ 2, and the rate of good prognoses was 38.9%. In the treatment of patients with severe acute BAO, intra-arterial mechanical thrombectomy combined with thrombolysis or stent placement are effective strategies to restore blood flow and preserve life, and these strategies have a low incidence of complications.

Thrombectomy in patients with large cerebral artery occlusion: a single-center experience with a new stent retriever

INTRODUCTION

The Trevo device, a new stent retriever, may be utilized in patients with large cerebral artery occlusion.

METHODS

Fifty patients with large cerebral artery occlusion and treated with the Trevo device were analyzed. Patients may have received intravenous thrombolysis as a bridging concept in addition to thrombectomy. Outcome and recanalization parameters were documented using the National Institutes of Health Scale, the modified Ranking Scale (mRS) and Thrombolysis in Cerebral Infarction (TICI) score.

RESULTS

In all, 82% (95% confidence interval [CI]: 69%-91%) were documented with TICI 2b and 3. Good clinical outcome after 90 days (mRS ≤ 2) was assessed in 61% (95% CI: 46%-75%). Symptomatic intracerebral hemorrhage occurred in 6 patients (12%, 95% CI: 1%-17%). The overall mortality rate was 14% (95% CI: 6%-27%).

CONCLUSION

Thrombectomy with the new stent retriever device is feasible and effective and has an acceptable risk of intra-cerebral hemorrhage even in combination with pharmacological revascularization techniques.

Neurothrombectomy in the treatment of acute ischaemic stroke

Major ischaemic stroke is a leading cause of morbidity and mortality in industrialized countries. For patients with acute stroke, fast and effective vessel recanalization is important for successful treatment. Neurothrombectomy--that is, angiographically performed mechanical thrombus removal from intracranial arteries--results in higher recanalization rates than with pharmaceutical thrombolysis alone, but the value of this treatment in terms of clinical outcome remains to be established. This article summarizes the history of intra-arterial stroke treatment, outlines the recent developments and the different techniques used, and discusses the results of current studies on neurothrombectomy. Owing to the high morphological and clinical variability of stroke, careful patient selection in future randomized controlled trials will be crucial for assessment of the true potential of neurothrombectomy.

Recanalization of acute intracranial artery occlusion using temporary endovascular bypass technique

PURPOSE

The purpose of this study is to present our preliminary experience of the temporary endovascular bypass (TEB) technique using an Enterprise stent for recanalization of acute intracranial artery (IA) occlusion.

MATERIALS AND METHODS

Patients treated by TEB were enrolled in this retrospective study from January 2009 to May 2010. All the procedures consist of temporary partial deployment and subsequent retrieval of Enterprise stent, supplemented by intra-arterial infusion of urokinase (UK) and/or tirofiban. According to the thrombolysis in cerebral infarction (TICI) classification, recanalization was evaluated with initial and postprocedural angiography. Safety was evaluated related to the procedure and clinical outcomes were assessed by National Institute of Health Stroke Scale (NIHSS) score at discharge and modified Rankin scale (mRS) score at 3 months.

RESULTS

Eleven patients (median NIHSS 12.8, mean age 61.6 years, male: female = 8:3) with acute IA occlusion were treated with TEB. All the patients presented with TICI 0, and the occluded vessel was the middle cerebral artery (n=7), the basilar artery (n=1), and the distal ICA occlusion (n = 3). IV infusion of tissue plasminogen activator (tPA) was done in 4 patients and mechanical thrombolysis with intra-arterial UK was performed in 9. Recanalization was achieved in 73% (8 patients; TICI ≥ 2). There were no procedure-related complications except for two asymptomatic intracranial hemorrhages. Improvement (≥ 4 points on the NIHSS) and good outcome (mRS ≤2) after 90 days was shown in six patients (55%). One patient died 6 days after procedure.

CONCLUSION

TEB may be a valuable treatment option in acute thromboembolic IA occlusion without stent implantation.

Retrievable stent thrombectomy in the treatment of acute ischemic stroke: analysis of a revolutionizing treatment technique

Acute ischemic stroke resulting from intracranial vessel occlusion is associated with high morbidity and mortality. The mainstays of therapy are fibrinolytics and mechanical thrombectomy in properly selected patients. A new Food and Drug Administration-approved technology to perform thrombectomy, retrievable stenting, may provide superior revascularization rates and improved patient outcomes. We analyzed the cumulative human experience reported for the Trevo Pro Retrieval System (Stryker, Kalamazoo, MI, USA) and the Solitaire FR Revascularization Device (ev3, Irvine, CA, USA) as the definitive treatment for acute ischemic stroke. A literature search was undertaken to identify studies using the retrievable stents published up to September 2012. Nineteen studies identified a total of 576 patients treated with either the Trevo (n=221) or Solitaire (n=355) devices. Pooled data analysis identified median baseline National Institutes of Health Stroke Scale scores of 18.5 ± 0.289 (standard error of the mean) and 17.9 ± 0.610, and time to recanalization of 53.9 ± 23.6 minutes and 59.0 ± 8.0 minutes for the Trevo and Solitaire groups, respectively. Recanalization was variably defined by individual studies, most commonly achieving at least a thrombolysis in cerebral infarction score of 2a-3 or a thrombolysis in myocardial infarction score of 2-3. Revascularization (83%, 82%), mortality (31%, 14%), hemorrhage (8%, 6%), device complications (5%, 6%), and good patient outcomes (51%, 47%) were found with the Trevo and Solitaire devices, respectively. Preliminary analysis reveals excellent clinical outcomes for retrievable stent technology. This may be attributable to both high rates of revascularization with a relatively short time to perfusion restoration.

Efficacy and safety of an early Solitaire stent retrieval technique for acute ischemic stroke

PURPOSE

The aim of this study was to retrospectively evaluate the efficacy and safety of early pull-back of a Solitaire stent as a thrombectomy device in patients with acute ischemic stroke.

METHODS

The study group comprised 23 consecutive cases presenting with acute ischemic stroke who were treated with intra-arterial therapy using the Solitaire device as a first-line endovascular procedure. The stent was deployed to cover the thrombus and then left in place for 1-2 min. Immediate angiographic results are presented. Neurologic status was assessed according to the NIH Stroke Scale score (NIHSS) and the modified Rankin Scale (mRS) score.

RESULTS

Successful recanalization (TICI grade ≥ 2b) was achieved in 21 of the 23 (91.3 %) treated vessels, and 6 of the patients showed immediate flow restoration after the deployment of the first stent. The mean number of passes for maximal recanalization was 1.96. There were no symptomatic procedure-related complications. Of the cases, 34.8 % improved by >10 points on the NIHSS at discharge; 30.4 % of cases revealed good functional outcome (mRS score 0-2) at 90 days.

CONCLUSIONS

The early retrieval technique with the Solitaire stent appears to be a safe and effective method in patients with acute ischemic stroke.

The combined use of mechanical thrombectomy devices is feasible for treating acute carotid terminus occlusion

BACKGROUND

Mechanical thrombectomy devices have recently been developed and approved for recanalization of intracranial arterial occlusion. Here, we investigated the feasibility of combined stent-assisted and clot aspiration mechanical thrombectomy for effective recanalization of acute carotid terminus occlusion (CTO).

METHODS

Ten consecutive patients with acute ischemic stroke secondary to CTO who underwent intra-arterial (IA) treatment with both stent retrieval and negative-pressured clot aspiration systems were enrolled. Periprocedural and radiologic findings and clinical outcomes were evaluated.

RESULTS

The median age was 69 years (range, 47-86 years), and the median initial NIHSS score was 17.5 (range, 12-33). Mechanical thrombectomy was performed using a combination of the Solitaire stents and Penumbra system. Thrombolysis in cerebral ischemia [TICI] grade II-III was achieved in eight patients (80.0 %); complete recanalization of the CTO (TICI III) was achieved in three of those patients. Any type of intracranial hemorrhages occurred in four patients (40.0 %), but parenchymal hematoma type 2 was not observed. Four patients died within 3 months (40.0 %).

CONCLUSIONS

Combined mechanical thrombectomy treatment was effective for recanalization of acute CTO. The combination of Solitaire and Penumbra devices can be considered as a treatment option for CTO.

Reduction in distal emboli with proximal flow control during mechanical thrombectomy: a quantitative in vitro study

BACKGROUND AND PURPOSE

To evaluate the impact of proximal flow control on efficacy and safety of mechanical thrombectomy in an in vitro middle cerebral artery occlusion.

METHODS

Three independent variables, including clot type, device (Merci Retriever, Solitaire FR, and Trevo devices), and use of a balloon guide catheter, were used to ascertain the impact of proximal flow control on the size and number of distal emboli generated during thrombectomy. Secondary end points were the recanalization rate and amount of flow restored.

RESULTS

Use of the balloon guide catheter during thrombectomy of the fragile, hard clot significantly reduced the formation of large distal emboli with a diameter >1 mm, regardless of the device used (P<0.01). Applying aspiration via the balloon guide catheter in place of the conventional guide catheter resulted in a significant increase of flow reversal (P<0.0001). Prior to thrombectomy, deployment of the stent-trievers produced immediate flow restoration through the soft and hard clot occlusions, 69.2 ± 27.3 and 45.5 ± 22.8 mL/min, respectively, that was preserved after the balloon inflation because of collateral flow via the posterior communication artery. After deployment but before thrombectomy, no flow was restored when using the Merci Retriever. After thrombectomy, complete flow restoration was achieved in a majority of cases. The Merci Retriever required more thrombectomy attempts to achieve hard clot removal compared with the stent-trievers when the conventional guide catheter was used (1.5 versus 1.1).

CONCLUSIONS

The risk of distal embolization was significantly reduced with the use of the balloon guide catheter.

Critical use of balloon angioplasty after recanalization failure with retrievable stent in acute cerebral artery occlusion

OBJECTIVE

Sudden major cerebral artery occlusion often resists recanalization with currently available techniques or can results in massive symptomatic intracranial hemorrhage (sICH) after thrombolytic therapy. The purpose of this study was to examine mechanical recanalization with a retrievable self-expanding stent and balloon in acute intracranial artery occlusions.

METHODS

Twenty-eight consecutive patients with acute intracranial artery occlusions were treated with a Solitaire retrievable stent. Balloon angioplasty was added if successful recanalization was not achieved after stent retrieval. The angiographic outcome was assessed by Thrombolysis in Cerebral Infarction (TICI) and the clinical outcomes were assessed by the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS).

RESULTS

At baseline, mean age was 69.4 years and mean initial NIHSS score was 12.5. A recanalization to TICI 2 or 3 was achieved in 24 patients (85%) after stent retrieval. Successful recanalization was achieved after additional balloon angioplasty in 4 patients. At 90-day follow-up, 24 patients (85%) had a NIHSS improvement of ≥4 and 17 patients (60%) had a good outcome (mRS ≤2). Although there was sICH, there was one death associated with the procedure.

CONCLUSION

Mechanical thromboembolectomy with a retrievable stent followed by additional balloon angioplasty is a safe and effective first-line therapy for acute intracranial artery occlusions especially in case of unsuccessful recanalization after stent thrombectomy.

Clinical outcome of neurointerventional emergency treatment of extra- or intracranial tandem occlusions in acute major stroke: antegrade approach with wallstent and solitaire stent retriever

BACKGROUND

Acute large cerebral artery occlusions respond poorly to systemic thrombolysis with recombinant tissue plasminogen activator (rTPA) alone. The value of stent retriever-based mechanical thrombectomy in patients with additional extracranial occlusion of the internal carotid artery (ICA), who require acute a priori extracranial stenting in order to reach the intracranial obstruction site, is not well known. We determined the outcome after emergency revascularization in acute stroke with tandem occlusions of the anterior circulation.

METHODS

According to specific inclusion/exclusion criteria, eligible stroke patients with large artery occlusions underwent mechanical recanalization with the Solitaire stent retriever. In case of a tandem occlusion, we performed an acute stenting with the Wallstent before thrombectomy. From October 2009 to March 2011, 50 patients were treated according to this protocol; time frames, clinical data, recanalization rates, and midterm outcome were recorded.

RESULTS

Forty-one patients had a large artery occlusion in the anterior circulation and nine in the posterior circulation. Mechanical recanalization was successful in 35/41 cases (85 %). Six of 41 patients (15 %) died in the acute phase. In 17/41 patients (42 %), thrombectomy was preceded by an emergency stenting in the extracranial portion of the internal carotid artery (ICA). National Institutes of Health Stroke Scale (NIHSS)/modified Rankin Scale (mRS) scores showed significant improvement in both the stenting group and the nonstenting group; there were no significant differences between the groups. At 90 days, 54 % of patients with emergency stenting had a good outcome.

CONCLUSIONS

Acute extracranial stenting with the Wallstent combined with intracranial Solitaire-based thrombectomy is safe and may lead to an improvement in neurological outcome in patients with an otherwise poor prognosis under i.v. thrombolysis alone.

Mechanical thrombectomy with solitaire stent retrieval for acute ischemic stroke in a Brazilian population

OBJECTIVE

Large vessel occlusion in acute ischemic stroke is associated with low recanalization rates under intravenous thrombolysis. We evaluated the safety and efficacy of the Solitaire AB stent in treating acute ischemic stroke.

METHODS

Patients presenting with acute ischemic stroke were prospectively evaluated. The neurological outcomes were assessed using the National Institutes of Health Stroke Scale and the modified Rankin Scale. Time was recorded from the symptom onset to the recanalization and procedure time. Recanalization was assessed using the thrombolysis in cerebral infarction score.

RESULTS

Twenty-one patients were evaluated. The mean patient age was 65, and the National Institutes of Health Stroke Scale scores ranged from 7 to 28 (average 17 ± 6.36) at presentation. The vessel occlusions occurred in the middle cerebral artery (61.9%), distal internal carotid artery (14.3%), tandem carotid occlusion (14.3%), and basilarartery (9.5%). Primary thrombectomy, rescue treatment and a bridging approach represented 66.6%, 28.6%, and 4.8% of the performed procedures, respectively. The mean time from symptom onset to recanalization was 356.5 ± 107.8 minutes (range, 80-586 minutes). The mean procedure time was 60.4 ± 58.8 minutes (range, 14-240 minutes). The overall recanalization rate (thrombolysis in cerebral infarction scores of 3 or 2b) was 90.4%, and the symptomatic intracranial hemorrhage rate was 14.2%. The National Institutes of Health Stroke Scale scores at discharge ranged from 0 to 25 (average 6.9 ± 7). At three months, 61.9% of the patients had a modified Rankin Scale score of 0 to 2, with an overall mortality rate of 9.5%.

CONCLUSIONS

Intra-arterial thrombectomy with the Solitaire AB device appears to be safe and effective. Large randomized trials are necessary to confirm the benefits of this approach in acute ischemic stroke.

Mechanical thrombectomy using a solitaire stent in acute ischemic stroke; initial experience in 40 patients

OBJECTIVE

This study was conducted in order to demonstrate the initial experience of the Solitaire AB stent in mechanical intracranial thrombectomy.

METHODS

We conducted a retrospective review of 40 consecutive patients who underwent intra-arterial Solitaire AB stent thrombectomy for treatment of acute ischemic strokes between October 2010 and November 2011. Demographic, clinical, and radiological presentations and outcomes were studied.

RESULTS

Twenty six men and 14 women with a mean initial National Institutes of Health Stroke Scale (NIHSS) score of 14.1 (range, 8-26) and a mean age of 65.4 (range, 32-89) years were included in this study. Occlusion sites were as follows: internal carotid artery (n = 11), middle cerebral artery M1 (n = 22), M2 (n = 5), and basilar artery (n = 2). Successful revascularization was achieved in 36 (90%) patients. The mean NIHSS score was 11.6 (range, 1-23) at 24 hours after the procedure, and 42.5% of patients showed a modified Rankin scale score of ≤ 2 at 90 days. New occlusion by migrated emboli was observed in one (2.5%) case. Post-procedural intracerebral hemorrhage occurred in only one case (2.5%), with an all-cause mortality of two (5%).

CONCLUSION

The Solitaire AB device is a relatively safe and effective tool for use in performance of mechanical thrombectomy in patients with acute ischemic stroke.

Use of stentrievers in acute stroke: tips, tricks, and current results

Stentrievers are stent-like devices used in the treatment of acute ischemic stroke. They have demonstrated efficacy in restoring the intracranial blood flow with low procedural times. This article is a synopsis of the available devices and different techniques. An extensive review of the literature summarizing all the data that have been published demonstrating their clinical impact and complications is also presented.

Retrospective multicenter study of Solitaire FR for revascularization in the treatment of acute ischemic stroke

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate safety and efficacy of the Solitaire FR device in the treatment of patients with acute ischemic stroke secondary to large artery occlusion.

METHODS

We conducted a retrospective study of consecutive patients presenting with acute ischemic stroke treated with Solitaire FR as the first-line device to restore blood flow in 6 experienced European centers. This study was entirely funded and supported by Coviden Neurovascular. An independent Corelab determined modified Thrombolysis in Cerebral Infarction scores on the preprocedure and postprocedure angiograms. Complete revascularization was defined as modified Thrombolysis in Cerebral Infarction 2b or 3 post-Solitaire FR device use. Symptomatic intracranial hemorrhage was defined as parenchymal hemorrhage Type 2 associated with a decline of ≥ 4 points in the National Institutes of Health Stroke Scale score within 24 hours or causing death. Favorable functional outcome was considered as modified Rankin Scale score ≤ 2 at Day 90.

RESULTS

We studied 141 patients (mean age, 66 years; median National Institutes of Health Stroke Scale, 18); 74 patients received intravenous tissue-type plasminogen activator before endovascular treatment. Complete revascularization was achieved in 120 of 142 occlusion sites (85%) and good outcome in 77 of 141 (55%) patients. Good outcome was more frequent in patients treated with intravenous tissue-type plasminogen activator than in those without (66% versus 42%; P<0.01). Symptomatic intracranial hemorrhage was reported in 5 patients (4%) and 29 of 141 (20%) patients died or were lost during follow-up (3 cases).

CONCLUSIONS

This retrospective study with centralized evaluation shows that the use of Solitaire FR is safe and achieves good revascularization rates and functional outcomes in patients with acute ischemic stroke and large artery occlusion.

Comparison of stent-retriever devices versus the Merci retriever for endovascular treatment of acute stroke

BACKGROUND AND PURPOSE

Revascularization of large cerebral artery occlusion is the therapeutic goal in stroke therapy. Currently, many recanalization devices are in clinical use. This study compares the outcome parameters, efficacy, and safety of the new generation of stent-retriever devices with the well-established Merci retriever.

MATERIALS AND METHODS

All patients who received endovascular mechanical recanalization therapy were prospectively registered. One hundred twenty-two patients were treated with either new stent retrievers, including the Trevo and Solitaire devices, or the Merci retriever system. Recanalization of the occluded vessel was assessed in accordance with the modified TICI score, and outcome parameters, including the NIHSS and mRS scores, were documented. Clinical status was recorded after neurointervention, at time of discharge, and after 90 days.

RESULTS

The mean age of all patients was 68 years; 54% were male, with no statistical differences in demographics between both groups. Successful recanalization (TICI 3 and TICI 2b) was achieved in 82% of patients treated with stent retrievers compared with 62% of patients treated with Merci retrievers (P = .016). In the 90-day follow-up, 65% of patients treated with stent retrievers and 35% of those treated with the Merci had achieved a good (mRS = 0-2) clinical outcome (P = .002). Patients treated with stent retrievers had a significantly shorter treatment time (72 versus 122 minutes, P < .01) and less severe intracerebral hemorrhages (10% versus 28%, P < .01).

CONCLUSIONS

Patients treated with Trevo and Solitaire stents had a better revascularization rate, better clinical outcome, and lower complication rate than patients treated with the Merci retriever.

Technical feasibility and application of mechanical thrombectomy with the Solitaire FR Revascularization Device in acute basilar artery occlusion

BACKGROUND AND PURPOSE

Acute BAO is a devastating neurological condition associated with a poor clinical outcome and a high mortality rate. Recanalization has been identified as a major prognostic factor for good outcome in BAO. Mechanical thrombectomy using retrievable stents is an emerging treatment option for acute stroke. First clinical trials using stent retrievers have shown promising high recanalization rates. However, these studies mainly included large artery occlusions in the anterior circulation with only a few or single cases of BAO. Therefore, the purpose of this study was to evaluate technical feasibility, safety, and efficacy of mechanical thrombectomy using retrievable stent in the treatment of acute BAO.

MATERIALS AND METHODS

Fourteen consecutive patients with BAO undergoing endovascular therapy using retrievable stents (Solitaire FR Revascularization Device) were included. Additional multimodal treatment approaches included thromboaspiration, intravenous and/or intra-arterial thrombolysis, and PTA/ permanent stent placement. Recanalization rates after multimodal therapy and stent retrieval were determined. Clinical outcome and mortality were assessed 3 months after treatment.

RESULTS

Median patient age was 64.5 years (range 55-85). Median NIHSS score at presentation was 21 (range 5-36). Overall, successful recanalization (TICI 3 or 2b) was achieved in all patients (TICI 3 in 78.6%, 11/14). In 4 patients (28.6%), insufficient recanalization after stent retrieval was due to an underlying atherosclerotic stenosis. Additional deployment of a permanent intracranial stent was performed in 3 patients (21.4%) and PTA alone in 1 patient (7.1%), resulting in final TICI 3 in 1 patient and TICI 2b in 3 patients. Stent retrieval alone was performed in 4 patients (28.6%). Average number of device passes was 1.3 (range 1-3). Median procedure time to maximal recanalization was 47 minutes (range 10-252). No device-related complications or thromboembolic occlusion of a previously unaffected artery occurred. There was no symptomatic intracranial hemorrhage. At 3 months, good functional outcome (mRS 0-2) was observed in 28.6% (4/14); overall mortality was 35.7% (5/14).

CONCLUSIONS

A multimodal endovascular approach using retrievable stents in BAO has high recanalization rates, with very low complication rates. Underlying atherothrombotic stenotic lesions of the basilar artery may still necessitate additional permanent stent placement to achieve complete recanalization.

Safety and efficacy of mechanical thrombectomy with solitaire stent retrieval for acute ischemic stroke: a systematic review

Purpose

In recent years, mechanical thrombectomy using Solitaire stent retrieval has been tried for treating acute ischemic stroke with a large artery occlusion. We systematically reviewed published articles to appraise the evidence that supports the safety and efficacy of the mechanical thrombectomy in acute strokes with Solitaire stent.

Materials and Methods

Systematic searches using Medline and Scopus were performed for studies evaluating mechanical thrombectomy using a Solitaire stent in acute ischemic stroke. Articles were included if they were published since 2008, contained at least 5 subjects, and provided clinical results.

Results

Thirteen articles (262 cases) were included in this review. The mean time of the procedures ranged from 37 to 95.6 minutes in 10 studies. The success of recanalization was achieved in 89.7% and the recanalization rate varied from 66.7% to 100% in all 13 studies. The overall rates of the symptomatic hemorrhagic complications and mortality were 6.8% and 11.1%, respectively. A favorable outcome of mRS 2 or under was 47.3%. Procedure-induced complications developed in 3.4%.

Conclusion

The present review suggested that mechanical thrombectomy using a Solitaire stent in acute ischemic stroke was effective in recanalizing the occluded artery. The rate of procedural complications was small.

Endovascular mechanical recanalisation after intravenous thrombolysis in acute anterior circulation stroke: the impact of a new temporary stent

PURPOSE

Treatment of acute stroke by endovascular mechanical recanalisation (EMR) has shown promising results and continues to be further refined. We evaluated the impact of a temporary stent compared with our results using other mechanical devices.

MATERIALS AND METHODS

We analysed clinical and radiological data of all patients who were treated by EMR after intravenous thrombolysis for acute carotid T- and middle-cerebral artery (M1) occlusions at our centre between 2007 and 2011. A comparison was performed between those patients in whom solely the stent-retriever was applied (group S) and those treated with other devices (group C).

RESULTS

We identified 14 patients for group S and 16 patients for group C. Mean age, National Institute of Health Stroke Scale score, and time to treatment were 67.1 years and 16.5 and 4.0 h for group S and 61.1 years and 17.6 and 4.5 h for group C, respectively. Successful recanalisation (thrombolysis in cerebral infarction scores ≥IIb) was achieved in 93% of patients in group S and 56% of patients in group C (P < 0.05). Mean recanalisation times for M1 occlusions were 23 min (group S) and 29 min (group C) and for carotid-T occlusions were 39 min (group S) and 50 min (group C), and 45% of the patients in group S and 33% in group C had a favourable outcome (Modified Rankin Scale score ≤2).

CONCLUSION

The findings suggest an improvement in recanalisation success by the application of a temporary stent compared with previously used devices. These results are to be confirmed by larger studies.

Intra-arterial therapy for acute ischemic stroke

Intra-arterial therapy (IAT) for acute ischemic stroke refers to endovascular catheter-based approaches to achieve recanalization using mechanical clot disruption, locally injected thrombolytic agents or both. IAT may be used in addition to intravenous tissue plasminogen activator (tPA) or in patients who do not qualify for tPA, usually because they are outside the approved 3-h timeframe window or have contraindications, such as elevated international normalized ratio or partial thromboplastin time. Recanalization rates correlate with clinical improvement, and with the newest catheters it is possible to achieve recanalization in roughly 80% of patients treated. However, while the catheters are approved by the Food and Drug Administration, there are still no randomized trial data demonstrating the role of current IAT therapy vs either tPA or standard management. IAT is reserved for patients with large artery occlusions in the basilar, distal carotid, or proximal middle cerebral arteries. Imaging the penumbra using magnetic resonance imaging or computed tomographic perfusion is currently the most frequently used way to identify patients who might benefit. However, the imaging and clinical criteria for identifying which patients benefit, and perhaps more importantly those who will do poorly despite IAT, remain unclear.