Manual aspiration thrombectomy through balloon-tipped guide catheter for rapid clot burden reduction in endovascular therapy for ICA L/T occlusion

A Case of Carotid Sinus Reflex Caused by Manual Aspiration Thrombectomy Using a Balloon Guide Catheter

When starting a mechanical thrombectomy, manual aspiration with balloon guide catheters inserted into the internal carotid artery (ICA) is an efficient method for thrombus aspiration. However, no complications associated with this procedure have been reported. This study describes the case of a 76-year-old man who presented to our hospital with total aphasia and complete right-sided paralysis due to chronic atrial fibrillation and left occlusion of the ICA. When the balloon guide catheter was inserted and inflated at the origin of the left ICA, the patient's systolic blood pressure suddenly decreased from 114 mm Hg to 44 mm Hg. This sudden hypotension may have been caused by the carotid sinus reflex. Hypotension improved following balloon deflation. The procedure was continued, resulting in complete recanalization of the left ICA. The patient died from acute exacerbation of interstitial pneumonia. Although this complication is rare, similar phenomena have been recognized in carotid artery stenting and the use of flow-diverting devices. To the best of our knowledge, this is the first report of a case wherein the carotid sinus reflex was induced by manual aspiration using a balloon guide catheter placed in the ICA. Clinicians should recognize the importance of ensuring that the proximal end of the balloon crosses the carotid sinus when dilating and occluding the ICA with a balloon to avoid the carotid sinus reflex.

Basilar artery recanalization by proximal balloon occlusion and aspiration in a single vessel vertebrobasilar system: A case report

The authors present a case of a patient with a hypoplastic right vertebral artery (VA) ending in the posterior inferior cerebellar artery who sustained an acute onset basilar artery occlusion. A balloon-guided catheter was used to proximally occlude the dominant left VA, and aspiration was applied until reversal of flow was achieved in the basilar artery. Thus, basilar artery reperfusion was achieved without the need for stent-retrieval thrombectomy. We believe this represents the first described case of successful thrombectomy in the vertebrobasilar system using only proximal artery occlusion and aspiration. This novel technique may decrease the time to recanalization and improve outcomes for patients with acute basilar artery occlusion in the setting of a hypoplastic contralateral VA.

A multiscale computational framework to evaluate flow alterations during mechanical thrombectomy for treatment of ischaemic stroke

The treatment of ischaemic stroke increasingly relies upon endovascular procedures known as mechanical thrombectomy (MT), which consists in capturing and removing the clot with a catheter-guided stent while at the same time applying external aspiration with the aim of reducing haemodynamic loads during retrieval. However, uniform consensus on procedural parameters such as the use of balloon guide catheters (BGC) to provide proximal flow control, or the position of the aspiration catheter is still lacking. Ultimately the decision is left to the clinician performing the operation, and it is difficult to predict how these treatment options might influence clinical outcome. In this study we present a multiscale computational framework to simulate MT procedures. The developed framework can provide quantitative assessment of clinically relevant quantities such as flow in the retrieval path and can be used to find the optimal procedural parameters that are most likely to result in a favorable clinical outcome. The results show the advantage of using BGC during MT and indicate small differences between positioning the aspiration catheter in proximal or distal locations. The framework has significant potential for future expansions and applications to other surgical treatments.

Mechanical Thrombectomy for Acute Common Carotid Artery Occlusion

Mechanical thrombectomy (MT) is the standard treatment for acute large occlusion of the cerebral artery. Evidence for the success of this procedure was based on the treatment of patients with internal carotid artery and middle cerebral artery thrombi. There are a few reports on thrombi extending to the common carotid artery (CCA). We document our endovascular procedure and the clinical outcome in seven consecutive patients who underwent MT for CCA thrombi between September 2016 and April 2021. Their mean National Institutes of Health Stroke Scale score was 20.0 (range, 9-30), and the mean diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score on magnetic resonance images was 8.7 (range, 7-10). In six patients, MT of the CCA occlusion was successful, and the mean puncture-to-reperfusion time was 84 minutes (range, 39-211 minutes). In five patients, successful reperfusion was obtained. The mean total pass number was 4.1 (range, 2-7). Due to large thrombi, we performed balloon guide catheter (BGC) occlusion in three patients. Sheath occlusion occurred in two, and thrombus migration into the femoral artery around the sheath was observed in two patients. The mean modified Rankin Scale score 3 months post-stroke was 3.6 (range, 2-5). When the removal of a large CCA thrombus is attempted in a single step, catheter and sheath occlusion may occur, and this increases the risk for critical systemic artery occlusion. Therefore, we suggest that MT be combined with the BGC technique and propose the use of a large aspiration catheter to decrease the volume of the thrombus.

Comparison of vacuum pressures and suction forces generated by different pump systems for aspiration thrombectomy

Objective

Aspiration thrombectomy is used to treat endovascular stroke treatment by clot removal through vacuum and suction forces. We aimed to investigate the pressures and suction forces generated by different pump systems for aspiration.

Methods

Vacuum pressure was measured using a vacuum gauge with a closed tip for a 60cc syringe and aspiration pumps. Using an artificial thrombus made from polyvinyl alcohol hydrogel and latex membrane, we assessed the catheter tip force generated on an artificial thrombus using 5Fr Sofia and 6Fr Sofia PLUS intermediate catheters combined with Penumbra Jet Engine or Stryker Medela AXS Universal Aspiration Set. Subsequently, we calculated the catheter tip forces based on the pressure [catheter tip size (force = area × pressure)], and compared with the measured catheter tip force.

Results

The 60cc syringe generated the highest vacuum pressure. Among the automatic pumps, the Penumbra jet engine generated the highest vacuum pressure. The catheter tip forces on the artificial thrombus and latex membrane were 18.5 ± 1.70 and 8.0 ± 1.23 gf, respectively, and 13.9 ± 1.37 and 5.6 ± 0.83 gf, respectively using the 5 Fr Sofia with the Penumbra Jet Engine and the Stryker Medela AXS Universal Aspiration Set, respectively. The corresponding values for the 6 Fr Sofia PLUS with the Penumbra Jet Engine and Stryker Medela AXS Universal Aspiration Set were 39.7 ± 3.88 and 20.7 ± 0.92 gf and 25.4 ± 4.96 and 18.0 ± 0.84 gf. For a constant catheter diameter and the automatic pump, the catheter tip force was significantly larger in the artificial thrombus than latex membrane (p < 0.001, ANOVA).

Conclusion

The catheter diameter, vacuum pressure, and clot softness are positively correlated with the catheter tip force.

Comparison of aspiration versus combined technique as first-line approach in terminal internal carotid artery occlusion: a multicenter experience

BACKGROUND

There is no consensus on the most effective endovascular technique to use in patients with acute ischemic stroke due to terminal internal carotid artery (ICA) occlusion. The aim of this study was to compare safety and efficacy of the aspiration technique (AT) and combined technique (CT) as first-line approach in terminal ICA occlusions.

METHODS

We performed a retrospective analysis of prospectively collected databases from seven Italian stroke centers. Patients were divided into two subgroups according to the first-line approach: AT group or CT group. We followed the STROBE guidelines for cohort studies. We used Chi-square test, one-way and multivariate ANOVA analysis, together with contrast analysis and post hoc tests, logistic regression and Pearson's bivariate correlation for the statistical analyses.

RESULTS

Between January 2018 and August 2020, 353 patients were treated for a terminal ICA occlusion, with either AT or CT. CT was associated with a higher Thrombolysis in Cerebral Infarction (TICI) 2B-3 after the first pass (51.0% vs 26.9%) and at the end of the procedure (84% vs 73.3%) and with an improved clinical outcome at discharge (modified Rankin Scale (mRs) 0-2 of 47.8% vs 34.0%) and at 3 months' follow-up (mRs 0-2 of 56.5% vs 38.9%) compared with AT.

CONCLUSION

Thrombectomy of terminal ICA occlusions obtained using CT as first-line approach demonstrated better technical and functional outcomes in comparison with AT.

Importance of Occlusion Site for Thrombectomy Technique in Stroke: Comparison Between Aspiration and Stent Retriever

BACKGROUND AND PURPOSE

Thrombectomy with stent retriever and direct aspiration are equally effective in the endovascular treatment of anterior circulation acute ischemic stroke. We report efficacy and safety of initial treatment technique per occlusion segment.

METHODS

For this study, we analyzed data from the MR CLEAN Registry, a prospective, observational study in all centers that perform endovascular therapy in the Netherlands. We used ordinal logistic regression analysis to compare clinical and technical results of first line direct aspiration treatment with that of stent retriever thrombectomy stratified for occlusion segment. Primary outcome measure was functional outcome at 3 months. Secondary outcome measures included reperfusion grade expressed as the extended Thrombolysis in Cerebral Infarction score, periprocedural complication risk, time to reperfusion, and mortality.

RESULTS

Of the 2282 included patients, 1658 (73%) were initially treated with stent retriever and 624 (27%) with aspiration. Four hundred sixty-two patients had an occlusion of the intracranial part of the carotid artery, 1349 of the proximal middle cerebral artery, and 471 of the distal parts of the middle cerebral artery. There was no difference in functional outcome between aspiration and stent retriever thrombectomy (odds ratio, 1.0 [95% CI, 0.9-1.2]) in any of the occlusion segments (P value for interaction=0.2). Reperfusion rate was higher in the aspiration group (odds ratio, 1.4 [95% CI, 1.1-1.6]) and did not differ between occlusion segments (P value for interaction=0.6). Procedure times were shorter in the aspiration group (minutes 50 versus 65 minutes; P<0.0001). There was no difference in periprocedural complications or mortality.

CONCLUSIONS

In unselected patients with anterior circulation infarcts, we observed equal functional outcome of aspiration and stent retriever thrombectomy in all occlusion segments. When aspiration was the first line treatment modality, reperfusion rates were higher and procedure times shorter in all occlusion segments.

Evolution of Stroke Thrombectomy Techniques to Optimize First-Pass Complete Reperfusion

Since 2015, endovascular therapy (EVT) has become the standard of care for acute ischemic stroke (AIS) due to large vessel occlusion. It is a safe and highly effective treatment, and its number needed to treat of 2.6 is one of the highest throughout medicine. The ultimate goal when performing EVT is to maximize chances of good outcome through achievement of fast first-pass complete reperfusion, as incomplete and delayed reperfusion increases complication rates and negatively affects outcome. Since EVT has been established as standard of care, new devices have been developed and treatment techniques have been refined. This review provides a brief overview about the rationale for and history of EVT, followed by a detailed step-by-step description of how to perform EVT using the BADDASS (BAlloon guide with large bore Distal access catheter with Dual Aspiration with Stent-retriever as Standard approach), a combined technique, which is in our opinion the safest and most effective way to achieve fast first-pass complete reperfusion. We also discuss treatment strategies for patients with simultaneous high-grade carotid stenosis/pseudoocclusion/occlusion and gaining carotid access in challenging arch anatomy, as these are commonly encountered situations in AIS, and conclude with an outlook on new technologies and future directions of EVT.

Comparison of Aspiration versus Stent Retriever Thrombectomy as the Preferred Strategy for Patients with Acute Terminal Internal Carotid Artery Occlusion: A Propensity Score Matching Analysis

BACKGROUND AND PURPOSE

There is no consensus on endovascular treatment for terminal ICA. The purpose of this study was to evaluate the comparative safety and efficacy of preferred aspiration thrombectomy and stent retriever thrombectomy for revascularization in patients with isolated terminal ICA occlusion.

MATERIALS AND METHODS

We conducted a retrospective analysis of patients with terminal ICA occlusion treated with aspiration thrombectomy or stent retriever thrombectomy in our center, from September 2013 to November 2018. To minimize the case bias, propensity score matching was performed. The primary outcomes were successful reperfusion defined by expanded TICI grades 2b-3 at the end of all endovascular procedures and puncture-to-reperfusion time.

RESULTS

A total of 109 consecutive patients with terminal ICA occlusion were divided into the aspiration thrombectomy group (40 patients) and the stent retriever thrombectomy group (69 patients), and 30 patients were included in each group after propensity score matching. The proportion of complete reperfusion was significantly higher in the aspiration thrombectomy group (OR 4.75 [95% CI, 1.10-1.38]; P = .002). The median puncture-to-reperfusion time in the aspiration thrombectomy group was shorter than that in the stent retriever thrombectomy group (38  versus 69 minutes; P = .001). Fewer intracerebral hemorrhage events were recorded in the aspiration thrombectomy group (OR 0.29 [95% CI, 0.09-0.90]; P = .028). No significant differences were observed for good outcomes (OR 1.92 [95% CI, 0.86-4.25]) and mortality (OR 0.84 [95% CI, 0.29-2.44]) at 90 days.

CONCLUSIONS

For the treatment of terminal ICA occlusion, aspiration thrombectomy was technically superior to stent retriever thrombectomy in the absence of a balloon guide catheter in achieving successful reperfusion with shorter puncture-to-reperfusion time and procedure-related adverse events.

Role of Balloon Guide Catheter in Modern Endovascular Thrombectomy

Proximal flow control achieved with a balloon guide catheter (BGC) during endovascular treatment of acute ischemic stroke is reviewed in this article. In clinical practice, BGCs offer a multi-faceted approach for clot retrieval by creating proximal flow arrest, reducing embolic burden, and shortening procedure time. Evaluation of frontline thrombectomy procedures with BGCs revealed advantages of combined use over the conventional guide catheter (CGC), notably in the significant reduction of distal emboli to both the affected and previously unaffected territories. Recently, new measures of early and complete reperfusion at first thrombectomy pass have been identified as independent predictors of improved outcomes, which were consistently demonstrated with use of BGC as a safe and effective option to minimize number of passes during intervention. Prior randomized controlled trials reported the positive correlation between BGC-treated patients and a lower risk of mortality as well as shortened procedure time. While BGC use is more common in stent retriever-mediated mechanical thrombectomy, preliminary data has shown the potential benefit of device application during contact aspiration thrombectomy to achieve successful recanalization. However, the question of which major endovascular strategy reigns superior as a frontline remains to be answered. Along with clinical case assessments, BGC performance during in-vitro simulation was analyzed to further understand mechanisms for optimization of thrombectomy technique.

Predictors of Balloon Guide Catheter Assistance Success in Stent-retrieval Thrombectomy for an Anterior Circulation Acute Ischemic Stroke

Introduction Mechanical thrombectomy has become the standard treatment for large vessel occlusion (LVO) in acute ischemic stroke (AIS) in well-selected patients. Although many devices and strategies exist, the use of a balloon-tip guide catheter (BGC) with stent-retriever (SR) may hold several advantages. We aim to assess the efficacy and identify predictors of technical success of this unique approach. Methods From our prospectively maintained database, we identified consecutive cases in which a BGC was used for stent-retriever thrombectomy in anterior circulation LVO between 2015 and 2016. Baseline and procedural characteristics were captured and analyzed. Predictors of technical and clinical outcomes were identified by multivariable logistic regression analysis. Results Ninety-three patients with AIS-LVO were treated with BGC-assisted mechanical thrombectomy. The mean age was 71 years old (SD 14), with 49.5% male (n=46). Pre-operative IV-tPA was administered in 55.9% (n=52) of cases. The most common location of occlusive thrombus was M1 (64.5%, n=60). Successful recanalization (mTICI=2b-3) was achieved in 86.0% (n=80) of cases while complete revascularization (mTICI-3) was achieved in 56.5% (n=52). There was a first-pass success rate of 52.7% (n=49). At discharge, 38.7% of the patients were functionally independent (mRS≤2). Multivariate analysis revealed that the middle cerebral artery location was strongly predictive of first-pass success, resulting in mTICI =2b revascularization (OR 7.10, p=0.018). Additionally, female gender (OR 2.85, p=0.042) and decreasing mTICI were associated with a poor clinical outcome (mRS≥4; OR 1.76, p=0.008). Conclusions BGC assistance in stent retrieval thrombectomy is safe and effective for AIS due to anterior circulation LVO. Further investigation is required to elucidate the optimal treatment strategy based on patient and disease characteristics.

Clot reduction prior to embolectomy: mSAVE as a first-line technique for large clots

Introduction

The “Stent retriever Assisted Vacuum-locked Extraction” (SAVE) technique is a promising embolectomy method for intracranial large vessel occlusion (LVO). We report our experience using a modified SAVE (mSAVE) approach for clot reduction prior to embolectomy in acute ischemic stroke patients with large clots.

Materials and methods

We retrospectively analyzed 20 consecutive patients undergoing mSAVE in our center due to intracranial LVO. Angiographic data (including first-pass and overall complete reperfusion, defined as an expanded Thrombolysis in Cerebral Infarction (eTICI) score of 3, rate of successful reperfusion (eTICI ≥2c), number of passes, time from groin puncture to reperfusion) and clinical data (favorable outcome at 90 days, defined as modified Rankin Scale (mRS) ≤2) were assessed.

Results

First-pass and overall eTICI 3 reperfusion was reached in 13/20 (65%) and 14/20 (70%), respectively. The rate of successful reperfusion (eTICI ≥2c) after one pass was 85% and on final angiogram 90% with an average number of 1.1 ± 0.3 attempts. Eight out of 11 (73%) ICA occlusions were reperfused successfully and 5 (46%) completely after a single pass. Median groin to reperfusion time was 33 minutes (IQR 25–46). A favorable clinical outcome was achieved in 9/20 (45%) patients at discharge and after 90 days, respectively.

Conclusion

Clot reduction followed by embolectomy (mSAVE) is feasible and may be an important tool in the treatment of large clots.

Balloon-Guide Catheters Are Needed for Effective Flow Reversal during Mechanical Thrombectomy

BACKGROUND AND PURPOSE

Blood flow management in the carotid artery during mechanical thrombectomy is crucial for safety and effectiveness. There is an ongoing discussion about whether balloon-guide catheters or large-bore sheaths are needed for effective flow management. We compared general flow characteristics of proximal aspiration through a large-bore sheath and a balloon-guide catheter in a porcine in vivo model.

MATERIALS AND METHODS

We investigated blood flow in a porcine common carotid artery with and without aspiration (VacLok syringe and Penumbra pump, Pump MAX) through an 8F-long sheath and an 8F balloon-guide catheter. Blood hemodynamics were assessed via continuous duplex sonography.

RESULTS

Average vessel diameter and baseline blood flow were 4.4 ± 0.2 mm and 244 ± 20 mL/min, respectively. For the 8F sheath, pump aspiration resulted in a significant flow reduction (225 ± 25 mL/min, P < .001), but with a persisting antegrade stream. Manual aspiration resulted in collapse of the vessel in 2 of 7 measurements and oscillatory flow with antegrade systolic and retrograde diastolic components in the remaining 5 measurements. Net flow was antegrade (52 ± 44 mL/min) in 3 and retrograde (-95 ± 52 mL/min) in the remaining 2 measurements. For balloon-guide catheters, balloon inflation always resulted in flow arrest. Additional pump or manual aspiration resulted in significant flow reversal of -1100 ± 230 and -468 ± 46 mL/min, respectively (both, P < .001).

CONCLUSIONS

Only balloon-guide catheters allow reliable blood flow arrest and flow reversal in combination with aspiration via syringes or high-flow pump systems. Aspiration through an 8F sheath results in either collapse of the vessel or oscillatory flow, which can result in a net antegrade or retrograde stream.

Consensus Statements by Korean Society of Interventional Neuroradiology and Korean Stroke Society: Hyperacute Endovascular Treatment Workflow to Reduce Door-to-Reperfusion Time

Recent clinical trials demonstrated the clinical benefit of endovascular treatment (EVT) in patients with acute ischemic stroke due to large vessel occlusion. These trials confirmed that good outcome after EVT depends on the time interval from symptom onset to reperfusion and that in-hospital delay leads to poor clinical outcome. However, there has been no universally accepted in-hospital workflow and performance benchmark for rapid reperfusion. Additionally, wide variety in workflow for EVT is present between each stroke centers. In this consensus statement, Korean Society of Interventional Neuroradiology and Korean Stroke Society Joint Task Force Team propose a standard workflow to reduce door-to-reperfusion time for stroke patients eligible for EVT. This includes early stroke identification and pre-hospital notification to stroke team of receiving hospital in pre-hospital phase, the transfer of stroke patients from door of the emergency department to computed tomography (CT) room, warming call to neurointervention (NI) team for EVT candidate prior to imaging, NI team preparation in parallel with thrombolysis, direct transportation from CT room to angiography suite following immediate decision of EVT and standardized procedure for rapid reperfusion. Implementation of optimized workflow will improve stroke time process metrics and clinical outcome of the patient treated with EVT.

Consensus Statements by Korean Society of Interventional Neuroradiology and Korean Stroke Society: Hyperacute Endovascular Treatment Workflow to Reduce Door-to-Reperfusion Time

Recent clinical trials demonstrated the clinical benefit of endovascular treatment (EVT) in patients with acute ischemic stroke due to large vessel occlusion. These trials confirmed that good outcome after EVT depends on the time interval from symptom onset to reperfusion and that in-hospital delay leads to poor clinical outcome. However, there has been no universally accepted in-hospital workflow and performance benchmark for rapid reperfusion. Additionally, wide variety in workflow for EVT is present between each stroke centers. In this consensus statement, Korean Society of Interventional Neuroradiology and Korean Stroke Society Joint Task Force Team propose a standard workflow to reduce door-to-reperfusion time for stroke patients eligible for EVT. This includes early stroke identification and pre-hospital notification to stroke team of receiving hospital in pre-hospital phase, the transfer of stroke patients from door of the emergency department to computed tomography (CT) room, warming call to neurointervention team for EVT candidate prior to imaging, neurointervention team preparation in parallel with thrombolysis, direct transportation from CT room to angiography suite following immediate decision of EVT and standardized procedure for rapid reperfusion. Implementation of optimized workflow will improve stroke time process metrics and clinical outcome of the patient treated with EVT.

Simple aspiration with balloon catheter technique (simple ABC technique) against proximal internal carotid artery occlusion in cases of cardiogenic cerebral embolism

Background In cases of acute ischemic stroke, manual aspiration of the thrombus is commonly performed with a balloon guiding catheter placed in the cervical segment of the internal carotid artery (ICA). However, most manual aspirations using a balloon guiding catheter are combined with inner catheters, as in the direct aspiration first pass technique (ADAPT). We experienced some cases of acute ischemic stroke with proximal ICA occlusion due to cardiogenic thrombus where we obtained sufficient recanalization by simple manual aspiration from inflated Optimo 9F balloon catheters (Tokai Medical Products, Japan) placed in the origin of the cervical segment of the ICA without any inner catheter or stent retriever. We perform by preference this procedure, named the simple Aspiration with Balloon Catheter (simple ABC) technique. Herein, we report two recent cases and discuss this procedure. Case presentation Case 1: An 80-year-old man with paroxysmal atrial fibrillation developed left ICA occlusion. We performed the simple ABC technique and obtained a large amount of dark red and white thrombus. Puncture-to-reperfusion time was 14 minutes with Thrombolysis in Cerebral Infarction (TICI) grade 3. Case 2: A 69-year-old man with chronic atrial fibrillation developed left internal carotid occlusion. We performed the simple ABC technique and obtained a large amount of dark red thrombus. Puncture-to-reperfusion time was 15 minutes with TICI grade 2b. Conclusion The simple ABC technique is useful to deal with a large amount of thrombus, shortens procedure time, enables less invasive thrombectomy, and can shift immediately to subsequent procedures such as delivering a stent retriever or ADAPT.

Mechanical thrombectomy in acute ischaemic stroke: a review of the different techniques

Endovascular mechanical thrombectomy (MT) is reserved for acute ischaemic stroke secondary to large vessel occlusion. The various MT techniques employed in the treatment of hyperacute strokes are constantly evolving with new devices and improvisation of existing technology (Wahlgren, et al 2016). In this review, we describe a variety of MT techniques gained from our experience of performing over 350 procedures in 7 years of providing a 24/7 service within the national framework of a hyperacute stroke centre. We outline a number of endovascular techniques, procedure limitations, and potential complications.

Endovascular management of extracranial occlusions at the hyperacute phase of stroke with tandem occlusions

BACKGROUND AND PURPOSE

The management of cervical artery occlusions in hyperacute stroke with tandem cervical/intracranial occlusions has not yet become standardized, especially when the circle of Willis is effective.

METHODS

We retrospectively analyzed the safety and accuracy of current approaches to manage the cervical occlusion in consecutive patients with tandem occlusions addressed for intracranial mechanical thrombectomy (MT) in our department from January 2012 to May 2017. The different approaches that could be performed in a same patient during the same procedure or hospitalization were analyzed separately.

RESULTS

We reported 64 approaches to manage the cervical occlusion in 49 patients with tandem occlusion (14% of MT): medical treatment alone in 16/64 (25%), stenting/angioplasty in 16/64 (25%), occlusion with coils in 12/64 (19%), angioplasty alone in 9/64 (14%), stent-retriever in 8/64 (12%), and/or thromboaspiration in 3/64 (5%). Early ipsilateral embolic recurrence occurred after 9/64 (14%) of them. It was strongly associated with the presence of a cervical intraluminal thrombus (P=0.001) and was then lower after occlusion with coils and stent-retriever compared to medical treatment alone and thromboaspiration (P=0.002). Occlusion with coils had a lower rate of radiological intracranial hemorrhage at 48-hour compared to other approaches (P=0.009). The 3-month rates of favorable outcome (P=0.806) and mortality (P=0.878) were similar. One delayed stroke was imputable to an occlusion with coils, for a median (Q1-Q3) follow-up of 10 (3-20) months.

CONCLUSIONS

Cervical occlusion with coils and thrombectomy with stent-retrievers may be relevant to prevent early embolic recurrence in cervical occlusions with intraluminal thrombus. Stent-retrievers should be further assessed as a first-line approach, since delayed stroke may occur following occlusion with coils. Medical treatment alone may be sufficient when no cervical intraluminal thrombus is present, the Willis polygon is effective, and the cervical occlusion can be crossed easily to perform the intracranial thrombectomy.

Endovascular suction thrombectomy for severe cerebral venous sinus thrombosis: A report of two cases

Cerebral venous sinus thrombosis (CVST) is a severe clinical condition that manifests with diverse symptoms that can be mild, taking the form of a headache, or can be life-threatening, with raised intracranial pressure and herniation. Despite systemic anticoagulation treatment, CVST still carries a mortality risk of approximately 10% because of the failure of venous recanalization by anticoagulants alone. This paper describes two cases with extensive CVST who presented with progressive neurological deterioration despite adequate systemic anticoagulation treatment. Both patients were successfully treated with endovascular clot removal using suction thrombectomy techniques with immediate recanalization of the sinuses and rapid radiographic improvement. The described therapy appears effective and safe; however, further studies are needed to validate the effectiveness of this treatment.

Novel and emerging technologies for endovascular thrombectomy

Endovascular thrombectomy device improvements in recent years have served a pivotal role in improving the success and safety of the thrombectomy procedure. As the intervention gains widespread use, developers have focused on maximizing the reperfusion rates and reducing procedural complications associated with these devices. This has led to a boom in device development. This review will cover novel and emerging technologies developed for endovascular thrombectomy.

Efficacy of Balloon-Guiding Catheter for Mechanical Thrombectomy in Patients with Anterior Circulation Ischemic Stroke

Objective

To evaluate the efficacy of balloon guiding catheter (BGC) during thrombectomy in anterior circulation ischemic stroke.

Methods

Sixty-two patients with acute anterior circulation ischemic stroke were treated with thrombectomy using a Solitaire stent from 2011 to 2016. Patients were divided into the BGC group (n=24, 39%) and the non-BGC group (n=38, 61%). The number of retrievals, procedure time, thrombolysis in cerebral infarction (TICI) grade, presence of distal emboli, and clinical outcomes at 3 months were evaluated.

Results

Successful recanalization was more frequent in BGC than in non-BGC (83% vs. 66%, p=0.13). Distal emboli occurred less in BGC than in non-BGC (23.1% vs. 57.1%, p=0.02). Good clinical outcome was more frequent in BGC than in non-BGC (50% vs. 16%, p=0.03). The multivariate analysis showed that use of BGC was the only independent predictor of good clinical outcome (odds ratio, 5.19: 95% confidence interval, 1.07–25.11). More patients in BGC were successfully recanalized in internal carotid artery (ICA) occlusion with small retrieval numbers (<3) than those in non-BGC (70% vs. 24%, p=0.005). In successfully recanalized ICA occlusion, distal emboli did not occur in BGC, whereas nine patients had distal emboli in non-BGC (0% vs. 75%, p=0.001) and good clinical outcome was superior in BGC than in non-BGC (55.6% vs. 8.3%, p=0.01).

Conclusion

A BGC significantly reduces the number of retrievals and the occurrence of distal emboli, thereby resulting in better clinical outcomes in patients with anterior circulation ischemic stroke, particularly with ICA occlusion.

Efficacy of Proximal Aspiration Thrombectomy for Using Balloon-Tipped Guide Catheter in Acute Intracranial Internal Carotid Artery Occlusion

Objective

Mechanical thrombectomy (MT) for acute intracranial internal carotid artery (ICA) occlusion is often complicated by difficult revascularization and non-involved territory embolization possibly related with larger clot-burden. This study aims to evaluate the efficacy of proximal aspiration thrombectomy (PAT) using a balloon-tipped guide catheter for clot-burden reduction in such cases with period-to-period analysis (period 1 : standard MT without PAT; period 2 : PAT first, then standard MT for the remaining occlusion).

Methods

Eighty-six patients who underwent MT for acute intracranial ICA occlusion were included in this analysis from the prospectively maintained stroke registry (33 patients in period 1 and 53 in period 2). In period 2, 'responder' was defined as a case where some amount of clot was retrieved by PAT and the following angiography showed partial or full recanalization.

Results

Fifteen of fifty-three patients in period 2 (28.3%) were 'responders' to PAT. There was a significantly higher incidence of atrial fibrillation in the 'responder' subgroup. Period 2 showed a significantly shorter puncture-to-reperfusion time (94.5 minutes vs. 56.0 minutes; p=0.002), a significantly higher Thrombolysis in Cerebral Infarction of 2b-3 reperfusion (45.5% vs. 73.6%; p=0.009), but only a trend for better 3-month favorable outcome (mRS 0–2; 36.4% vs. 54.7%; p=0.097). There was no increase in the incidence of procedure-related complications or intracranial hemorrhage in period 2.

Conclusion

A strategy of PAT before standard MT may result in shorter puncture-to-reperfusion time and better angiographic outcome than a strategy of standard MT for acute intracranial ICA occlusion.

Chronic innominate artery occlusion with hyperacute intracranial thromboembolism: Revascularization with simultaneous local thromboaspiration and mechanical thrombectomy

Chronic innominate artery occlusion with acute right internal carotid terminus thromboembolism and successful revascularization using simultaneous local thromboaspiration and mechanical thrombectomy has not been previously described. A 51-year-old male presented with transient left hemiparesis. A CT angiogram of the head and neck demonstrated chronic occlusion of the right innominate artery with no intracranial thromboembolism. More profound symptoms recurred twelve hours after admission. A diagnostic catheter-based angiogram confirmed occlusion of the innominate artery and identified hyper-acute right carotid terminus thromboembolism. Angioplasty of the innominate artery was followed by simultaneous mechanical and aspiration thrombectomy of the right internal carotid artery terminus. Combination local thromboaspiration and mechanical thrombectomy was shown in this case to be effective in achieving a favorable clinical outcome.

Endovascular treatment for Small Core and Anterior circulation Proximal occlusion with Emphasis on minimizing CT to recanalization times (ESCAPE) trial: methodology

ESCAPE is a prospective, multicenter, randomized clinical trial that will enroll subjects with the following main inclusion criteria: less than 12 h from symptom onset, age > 18, baseline NIHSS >5, ASPECTS score of >5 and CTA evidence of carotid T/L or M1 segment MCA occlusion, and at least moderate collaterals by CTA. The trial will determine if endovascular treatment will result in higher rates of favorable outcome compared with standard medical therapy alone. Patient populations that are eligible include those receiving IV tPA, tPA ineligible and unwitnessed onset or wake up strokes with 12 h of last seen normal. The primary end-point, based on intention-to-treat criteria is the distribution of modified Rankin Scale scores at 90 days assessed using a proportional odds model. The projected maximum sample size is 500 subjects. Randomization is stratified under a minimization process using age, gender, baseline NIHSS, baseline ASPECTS (8-10 vs. 6-7), IV tPA treatment and occlusion location (ICA vs. MCA) as covariates. The study will have one formal interim analysis after 300 subjects have been accrued. Secondary end-points at 90 days include the following: mRS 0-1; mRS 0-2; Barthel 95-100, EuroQOL and a cognitive battery. Safety outcomes are symptomatic ICH, major bleeding, contrast nephropathy, total radiation dose, malignant MCA infarction, hemicraniectomy and mortality at 90 days.

Lessons learnt from recent endovascular stroke trials: finding a way to move forward

The advent of stentrievers provided momentum for endovascular stroke therapy. Hopes were dampened after three randomized trials showed no clear benefit of endovascular therapy. This review discusses the results of these trials results and shortcomings. A detailed discussion will follow on the design, conduct and analysis of current and future endovascular stroke trials. Steps to improve the workflow of acute stroke cases from the time they enter the emergency department until endovascular reperfusion is achieved can significantly shorten the time from onset to successful reperfusion. These factors in addition to using novel approaches to analyze data and minimize delays caused by the consent process are perceived to be sufficient to demonstrate the efficacy of endovascular stroke therapy.

Optimal Workflow and Process-Based Performance Measures for Endovascular Therapy in Acute Ischemic Stroke

Background and Purpose—

We report on workflow and process-based performance measures and their effect on clinical outcome in Solitaire FR Thrombectomy for Acute Revascularization (STAR), a multicenter, prospective, single-arm study of Solitaire FR thrombectomy in large vessel anterior circulation stroke patients.

Methods—

Two hundred two patients were enrolled across 14 centers in Europe, Canada, and Australia. The following time intervals were measured: stroke onset to hospital arrival, hospital arrival to baseline imaging, baseline imaging to groin puncture, groin puncture to first stent deployment, and first stent deployment to reperfusion. Effects of time of day, general anesthesia use, and multimodal imaging on workflow were evaluated. Patient characteristics and workflow processes associated with prolonged interval times and good clinical outcome (90-day modified Rankin score, 0–2) were analyzed.

Results—

Median times were onset of stroke to hospital arrival, 123 minutes (interquartile range, 163 minutes); hospital arrival to thrombolysis in cerebral infarction (TICI) 2b/3 or final digital subtraction angiography, 133 minutes (interquartile range, 99 minutes); and baseline imaging to groin puncture, 86 minutes (interquartile range, 24 minutes). Time from baseline imaging to puncture was prolonged in patients receiving intravenous tissue-type plasminogen activator (32-minute mean delay) and when magnetic resonance–based imaging at baseline was used (18-minute mean delay). Extracranial carotid disease delayed puncture to first stent deployment time on average by 25 minutes. For each 1-hour increase in stroke onset to final digital subtraction angiography (or TICI 2b/3) time, odds of good clinical outcome decreased by 38%.

Conclusions—

Interval times in the STAR study reflect current intra-arterial therapy for patients with acute ischemic stroke. Improving workflow metrics can further improve clinical outcome.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01327989.

Mechanical thrombectomy with the Solitaire stent: is there a learning curve in achieving rapid recanalization times?

METHODS

In acute ischemic stroke, good outcome following successful recanalization is time dependent. In patients undergoing endovascular therapy at our institution, recanalization times with the Solitaire stent were retrospectively evaluated to assess for the presence of a learning curve in achieving rapid recanalization.

METHODS

We reviewed patients who presented to our stroke center and achieved successful recanalization with the Solitaire stent exclusively. Time intervals were calculated (CT to angiography arrival, angiography arrival to groin puncture, groin puncture to first deployment, and deployment to recanalization) from time stamped images and angiography records. Patients were divided into three sequential groups, with overall CT to recanalization time and subdivided time intervals compared.

RESULTS

83 patients were treated with the Solitaire stent from May 2009 to February 2012. Recanalization (Thrombolyis in Cerebral Infarction score 2A) occurred in 75 (90.4%) patients. CT to recanalization demonstrated significant improvement over time, which was greatest between the first 25 and the most recent 25 cases (161-94 min; p<0.01). The maximal contribution to this was from improvements in first stent deployment to recanalization time (p=0.001 between the first and third groups), with modest contributions from moving patients from CT to the angiography suite faster (p=0.02 between the first and third groups) and from groin puncture to first stent deployment (p=0.02 between the first and third groups).

CONCLUSIONS

There is a learning curve involved in the efficient use of the Solitaire stent in endovascular acute stroke therapy. Along with improvements in patient transfer to angiography and improved efficiency with intracranial access, mastering this device contributed significantly towards reducing recanalization times.

The outcome and efficacy of recanalization in patients with acute internal carotid artery occlusion

BACKGROUND AND PURPOSE

Acute occlusion of the ICA is often associated with poor outcomes and severe neurologic deficits. This study was conducted to evaluate outcome of the occluded ICA and efficacy of recanalization under protective flow arrest.

MATERIALS AND METHODS

Fifty consecutive patients who underwent endovascular treatment for acute ICA occlusion were identified from the prospectively collected data base. We assessed NIHSSo, occlusion type (cardioembolism vs atherosclerosis), occlusion level (supraclinoid-terminal, petrocavernous, or bulb-cervical), recanalization degree (TICI), and efficacy of recanalization (protective flow arrest vs nonprotection) leading to better outcome.

RESULTS

Successful recanalization (TICI ≥ 2) was obtained in 90% of patients and good recovery (mRS ≤ 2) in 60% of patients. Good outcome was related to National Institutes of Health Stroke Scale score on admission (P < .001), TICI (P < .007), occlusion type (P = .022), and occlusion level (P = .038). Poor initial patient status, less recanalization, cardioembolism, and supraclinoid-terminal occlusion were associated with poor prognosis. Application of protective flow arrest led to better outcome in the distal ICA segment than in the bulb-cervical segment.

CONCLUSIONS

In addition to the initial patient status and successful recanalization, the occlusion level or type of the occluded ICA could affect clinical outcome. In this study, treatment benefits of protective flow arrest were accentuated in patients with ICA occlusion above the bulb-cervical segment.

Future trials of endovascular mechanical recanalisation therapy in acute ischemic stroke patients - a position paper endorsed by ESMINT and ESNR : part II: methodology of future trials

Based on current data and experience, the joint working group of the European Society of Minimally Invasive Neurological Therapy (ESMINT) and the European Society of Neuroradiology (ESNR) make suggestions on trial design and conduct aimed to investigate therapeutic effects of mechanical thrombectomy (MT). We anticipate that this roadmap will facilitate the setting up and conduct of successful trials in close collaboration with our neighbouring disciplines.