Cyclical aspiration using a novel mechanical thrombectomy device is associated with a high TICI 3 first pass effect in large-vessel strokes

Impact of obesity-related indicators on first-pass effect in patients with ischemic stroke receiving mechanical thrombectomy

PURPOSE

The first-pass effect (FPE), defined as complete revascularization after a single thrombectomy pass in large vessel occlusion, is a predictor of good prognosis in patients with acute ischemic stroke (AIS) receiving mechanical thrombectomy (MT). We aimed to evaluate obesity-related indicators if possible be predictors of FPE.

METHODS

We consecutively enrolled patients with AIS who were treated with MT between January 2019 and December 2021 at our institution. Baseline characteristics, procedure-related data, and laboratory test results were retrospectively analyzed. A multivariable logistic regression analysis was performed to evaluate the independent predictors of FPE.

RESULTS

A total of 151 patients were included in this study, of whom 47 (31.1%) had FPE. After adjusting for confounding factors, the independent predictors of achieving FPE were low levels of body mass index (BMI) (OR 0.85, 95% CI 0.748 to 0.971), non-intracranial atherosclerotic stenosis (OR 4.038, 95% CI 1.46 to 11.14), and non-internal carotid artery occlusion (OR 13.14, 95% CI 2.394 to 72.11). Patients with lower total cholesterol (TC) (< 3.11 mmol/L) were more likely to develop FPE than those with higher TC (≥ 4.63 mmol/L) (OR 4.280; 95% CI 1.24 to 14.74) CONCLUSION: Lower BMI, non-intracranial atherosclerotic stenosis, non-internal carotid artery occlusion, and lower TC levels were independently associated with increased rates of FPE in patients with AIS who received MT therapy. FPE was correlated with better clinical outcomes after MT.

Experimental evaluation of the plunger technique: A method of cyclic manual aspiration thrombectomy for treatment of acute ischemic stroke

BACKGROUND

Mechanical thrombectomy via direct aspiration is a rapid treatment for acute ischemic stroke. This method often results in the partial ingestion of the clot or "corking" of the catheter tip. Cyclic aspiration may take advantage of the mechanical properties of the clot, resulting in greater clot ingestion and overall procedure success.

METHODS

An in vitro analysis was performed comparing static and cyclic (plunger technique) aspiration. Embolus analogs were used to create occlusions in a mock circulatory flow loop, and one aspiration attempt (first pass effect) using either a static or plunger technique was performed. The percent ingestion of each embolus analog was recorded for each trial.

RESULTS

Static aspiration for 0% and 50% hematocrit embolus analogs resulted in ingestions of 12.8 ± 4.6% and 15.1 ± 10.0%, respectively, while plunger technique (cyclic) aspiration resulted in 15.8 ± 7.3% and 34.4 ± 19.5% ingestion. Complete ingestion was observed only with 50% hematocrit analogs, occurring in 30% of plunger and 10% of static cases. Statistical differences were determined between the two aspiration techniques for the 50% hematocrit samples, with the plunger technique yielding significantly more ingestion. In addition, the plunger technique was shown to maintain a negative vacuum pressure throughout the duration of cyclic plunging.

CONCLUSIONS

The plunger technique for manual cyclic aspiration resulted in higher rates of complete ingestion and greater average % ingestions when compared to static aspiration. Increased clot ingestion can result in a higher rate of complete reperfusion during the first aspiration attempt, maximizing the number of patients with good clinical outcomes.

The 'plunger' technique for direct aspiration thrombectomy

Direct aspiration thrombectomy is often employed for endovascular treatment of acute ischemic stroke because it rapidly achieves recanalization. Ideally, the clot is completely or nearly completely ingested into the aspiration catheter. Static aspiration is typically used, either with an electrical pump1 or with a handheld syringe, which applies a fixed vacuum. However, cyclic or oscillating aspiration may lead to additional deformation of the clot, which allows for additional ingestion into the catheter.2-4 This video describes the use of the 'plunger' technique, wherein a 60 mL locking syringe is used to apply on/off vacuum force to the occlusive clot. This technique provides a simple, manual approach to cyclic aspiration for stroke thrombectomy (video 1).neurintsurg;jnis-2023-021067v2/V1F1V1Video 1.

A review of mechanical thrombectomy techniques for acute ischemic stroke

Mechanical thrombectomy is established as standard of care in the management of acute ischemic stroke due to large vessel occlusion and evidence-based guidelines for mechanical thrombectomy have been defined. As research continues to further expand the eligibility criteria for thrombectomy and the number of thrombectomy procedures increase worldwide, there is also growing focus on innovation of thrombectomy devices, procedural techniques, and related outcomes. Thrombectomy primarily involves use of stent retrievers and distal aspiration techniques, but variations and different combinations of techniques have been reported. As this is a rapidly evolving area in stroke management, there is debate as to which, if any, of these techniques leads to improved clinical outcomes over another and there is a lack of data comparing them. In this review, currently published and distinct techniques of mechanical thrombectomy are described methodically along with illustrations to aid in understanding the subtle differences between the techniques. The perceived benefits of each variation are discussed.

Clinical outcome of patients with mild pre-stroke morbidity following endovascular treatment: a HERMES substudy

BACKGROUND

Analyses of the effect of pre-stroke functional levels on the outcome of endovascular therapy (EVT) have focused on the course of patients with moderate to substantial pre-stroke disability. The effect of complete freedom from pre-existing disability (modified Rankin Scale (mRS) 0) versus predominantly mild pre-existing disability/symptoms (mRS 1-2) has not been well delineated.

METHODS

The HERMES meta-analysis pooled data from seven randomized trials that tested the efficacy of EVT. We tested for a multiplicative interaction effect of pre-stroke mRS on the relationship between treatment and outcomes. Ordinal regression was used to assess the association between EVT and 90-day mRS (primary outcome) in the subgroup of patients with pre-stroke mRS 1-2. Multivariable regression modeling was then used to test the effect of mild pre-stroke disability/symptoms on the primary and secondary outcomes (delta-mRS, mRS 0-2/5-6) compared with patients with pre-stroke mRS 0.

RESULTS

We included 1764 patients, of whom 199 (11.3%) had pre-stroke mRS 1-2. No interaction effect of pre-stroke mRS on the relationship between treatment and outcome was observed. Patients with pre-stroke mRS 1-2 had worse outcomes than those with pre-stroke mRS 0 (adjusted common OR (acOR) 0.53, 95% CI 0.40 to 0.70). Nonetheless, a significant benefit of EVT was observed within the mRS 1-2 subgroup (cOR 2.08, 95% CI 1.22 to 3.55).

CONCLUSIONS

Patients asymptomatic/without disability prior to onset have better outcomes following EVT than patients with mild disability/symptoms. Patients with pre-stroke mRS 1-2, however, more often achieve good outcomes with EVT compared with conservative management. These findings indicate that mild pre-existing disability/symptoms influence patient prognosis after EVT but do not diminish the EVT treatment effect.

The pioneering past and cutting-edge future of interventional neuroradiology

This review provides a thorough understanding of the developments in the field of interventional neuroradiology (INR). A concise overview of the pioneering past and current state of this field is presented first, followed by a greater emphasis on its future. Five main aspects predicted to undergo significant developments are identified and discussed. These include changes in 'education and training', 'clinical practice and logistics', 'devices and equipment', 'techniques and procedures', and 'relevant diagnostic imaging'. INR is at the crossroads of neuroradiology, neurosurgery, neurology, and the neurosciences. To progress we must value the uniqueness and vitality of this multidisciplinary aspect. While minimal access techniques offer very good anatomical accessibility to treat multiple pathologies of the central nervous system, it is also important to recognise its limitations. Medical, surgical, and radiosurgery modalities retain an important role in the management of some complex neuropathology. This review is certainly not exhaustive of all ongoing and predicted developments, but it is an important update for INR specialists and other interested professionals.

The Charlotte large artery occlusion endovascular therapy outcome score predicts outcome after basilar artery thrombectomy

BACKGROUND AND PURPOSE

The Charlotte Large artery occlusion Endovascular therapy Outcome Score (CLEOS) and Totaled Health Risks in Vascular Events (THRIVE) predict functional outcomes after anterior circulation endovascular thrombectomy (EVT). We evaluated the performance of CLEOS and THRIVE in patients presenting with an acute basilar artery occlusion (BAO) treated with EVT.

METHODS

We conducted a retrospective analysis of a health system's stroke registry. Patients presenting with an acute BAO treated with EVT and evaluated with pre-thrombectomy CT perfusion (CTP) from January 2017 to December 2021 were included. CLEOS = (5 × age) + (10 × National Institutes of Health Stroke Scale [NIHSS]) + Glucose - (150 × CTP cerebral blood volume index) and THRIVE (0-9 points) = age 60-79 years, 1 point; age ≥ 80 years, 2 points; NIHSS 11-20, 2 points; NIHSS ≥ 21, 4 points; hypertension, diabetes mellitus, atrial fibrillation, 1 point each. Multivariable logistic regression was performed for the ability of CLEOS and THRIVE to predict the primary outcome, modified Rankin Scale score 3-6.

RESULTS

Fifty-seven patients had mean age 66.6 (± 14.9) years and median NIHSS 15.5 (5-24). In the multivariable regression analysis, increased CLEOS was associated with significantly higher odds of a poor functional outcome (odds ratio [OR] = 1.0011, 95% confidence interval [CI]: 1.0003-1.0019, p = .008), whereas THRIVE was not (OR = 1.0326, 95% CI: 0.9478-1.1250, p = .466). CLEOS &gt; 503 best predicted poor outcomes.

CONCLUSIONS

A higher CLEOS score was associated with elevated odds of a poor 90-day functional outcome in our cohort of acute BAO patients treated with EVT.

REACT Aspiration Catheters: Clinical Experience and Technical Considerations

Aspiration catheters are widely used in mechanical thrombectomy procedures to treat acute ischemic stroke due to large vessel occlusion. The key performance requirements for aspiration catheters are ease of navigation and effective aspiration. In this work, we review the clinical experience and in vitro studies of REACT aspiration catheters (Medtronic, Minneapolis, MN, USA). In vitro experiments showed that REACT catheters exhibit solid performance in navigation and aspiration. Previous studies reported that the recanalization capacity of the aspiration catheters can be influenced by the devices’ inner diameter and tip distensibility, the catheter-to-vessel diameter ratio, the negative pressure delivered by the vacuum generator, the cyclical aspiration mode, the proximal flow arrest, and the angle of interaction between catheter and clot. REACT catheters can be navigated through the vasculature without any support from a microcatheter/ microwire in favorable anatomical configurations. In challenging situations, mostly encountered when crossing the ophthalmic segment of the internal carotid artery, the use of the stentriever anchoring technique or delivery assist catheter can facilitate the navigation. Three clinical studies reporting on 299 patients who underwent mechanical thrombectomy with REACT catheters were included in this review. Successful recanalization (modified treatment in cerebral ischemia score 2b–3) was achieved in 89–96% of cases, no procedural complications related to REACT catheters were reported, and functional independence (modified Rankin Scale 0–2) at 90-days was 24–36%. In vitro experimental evaluations and clinical studies support the safety and effectiveness of the REACT catheters.

Patient and procedure selection for mechanical thrombectomy: Toward personalized medicine and the role of artificial intelligence

Mechanical thrombectomy (MT) for ischemic stroke due to large vessel occlusion is standard of care. Evidence-based guidelines on eligibility for MT have been outlined and evidence to extend the treatment benefit to more patients, particularly those at the extreme ends of a stroke clinical severity spectrum, is currently awaited. As patient selection continues to be explored, there is growing focus on procedure selection including the tools and techniques of thrombectomy and associated outcomes. Artificial intelligence (AI) has been instrumental in the area of patient selection for MT with a role in diagnosis and delivery of acute stroke care. Machine learning algorithms have been developed to detect cerebral ischemia and early infarct core, presence of large vessel occlusion, and perfusion deficit in acute ischemic stroke. Several available deep learning AI applications provide ready visualization and interpretation of cervical and cerebral arteries. Further enhancement of AI techniques to potentially include automated vessel probe tools in suspected large vessel occlusions is proposed. Value of AI may be extended to assist in procedure selection including both the tools and technique of thrombectomy. Delivering personalized medicine is the wave of the future and tailoring the MT treatment to a stroke patient is in line with this trend.

Benefit of successful reperfusion achieved by endovascular thrombectomy for patients with ischemic stroke and moderate pre-stroke disability (mRS 3): results from the MR CLEAN Registry

BACKGROUND

Pre-stroke dependent patients (modified Rankin Scale score (mRS) ≥3) were excluded from most trials on endovascular treatment (EVT) for acute ischemic stroke (AIS) in the anterior circulation. Therefore, little evidence exists for EVT in those patients. We aimed to investigate the safety and benefit of EVT in pre-stroke patients with mRS score 3.

METHODS

We used data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic stroke in the Netherlands (MR CLEAN) Registry. All patients treated with EVT for anterior circulation AIS with pre-stroke mRS 3 were included. We assessed causes for dependence and compared patients with successful reperfusion (defined as expanded Thrombolysis in Cerebral Ischemia scale (eTICI) 2b-3) to patients without successful reperfusion. We used regression analyses with pre-specified adjustments. Our primary outcome was 90-day mRS 0-3 (functional improvement or return to baseline).

RESULTS

A total of 192 patients were included, of whom 82 (43%) had eTICI <2b and 108 (56%) eTICI ≥2b. The median age was 80 years (IQR 73-87). Fifty-one of the 192 patients (27%) suffered from previous stroke and 36/192 (19%) had cardiopulmonary disease. Patients with eTICI ≥2b more often returned to their baseline functional state or improved (n=26 (26%) vs n=15 (19%); adjusted odds ratio (aOR) 2.91 (95% CI 1.08 to 7.82)) and had lower mortality rates (n=49 (49%) vs n=50 (64%); aOR 0.42 (95% CI 0.19 to 0.93)) compared with patients with eTICI <2b.

CONCLUSIONS

Although patients with AIS with pre-stroke mRS 3 comprise a heterogenous group of disability causes, we observed improved outcomes when patients achieved successful reperfusion after EVT.

A fully radiopaque hybrid stent retriever versus a precursor device: Outcome, efficacy, and safety in large vessel stroke

BACKGROUND AND PURPOSE

The aim of this multicenter study was to compare the clinical outcome, safety, and efficacy of the full-length radiopaque Aperio Hybrid stent retriever (APH) with the precursor Aperio thrombectomy device (AP).

METHODS

Multicentric retrospective analysis of patients with stroke, treated with the APH and AP due to an acute ischemic stroke by large vessel occlusions in the anterior or posterior circulation, was performed. We focused on the comparison of favorable clinical outcome (modified Rankin Scale, 0-2) after 3 months, favorable reperfusion rates (thrombolysis in cerebral infarction scale ≥ 2b), and the complication rate.

RESULTS

A total of 51 patients (female: n = 33, 64.7%, mean age 73 ± 16 years) with a median baseline National Institutes of Health Stroke Scale: 15 were treated with the APH or AP. Favorable outcome in patients treated with APH was excellent (44.0%) and comparable to the AP (36.8%). The rate of final favorable reperfusion for both devices was outstanding (APH 31/31 and AP 20/20). The overall complication rate for the APH was slightly higher compared to the AP (32.3%/15.0%). Symptomatic intracranial hemorrhage was recorded in 0 of 51 cases. The all-cause mortality rate at 90 days was 20.0% for the APH and comparable for the AP (21.1%).

CONCLUSIONS

Comparable clinical outcome, efficacy, and safety of the AP and the recently introduced APH were demonstrated. Both devices appeared feasible, efficient, and safe with regard to endovascular treatment in large vessel occlusion.

Evidence-Based Updates to Thrombectomy: Targets, New Techniques, and Devices

Endovascular thrombectomy (EVT) has been validated in several randomized controlled trials in recent years for its efficacy in the treatment of acute ischemic strokes (AIS) and is now the standard of care according to international guidelines. However, in about 20% of EVT procedures, recanalization is not achieved, and over 50% of patients who undergo EVT still do not have good functional outcome. In this article, we provide an extensive review of the latest evidence and developments in the field of EVT, with particular focus on the factors that improve patient outcomes. These factors include new and adjunctive techniques such as combination of direct aspiration and stent retriever, intra-arterial urokinase or 2b/3a inhibitors, rescue stenting, as well as novel devices including balloon guide catheters and the newer generations of aspiration catheters and stent retrievers. We also examined the latest notion of using first-pass effect (FPE) as the target to achieve during EVT, which has been associated with an improved functional outcome. While the field of EVT has been rapidly evolving, further research is required in specific AIS patient populations such as those with large ischemic core, late presentation beyond 24 h, posterior circulation strokes, and with distal medium vessel occlusion or tandem lesions to better assess its efficacy and safety.