Risk of distal embolization with stent retriever thrombectomy and ADAPT

Post-procedural plasma D-dimer level may predict futile recanalization in stroke patients with endovascular treatment

OBJECTIVE

High d-dimer levels may increase the likelihood of unfavorable clinical outcomes in patients with acute ischemic stroke. However, the impacts of serum d-dimer levels on outcomes of reperfusion treatment in patients with acute ischemic stroke have not been evaluated. This study aims to assess a possible relationship between serum d-dimer and functional outcomes in stroke patients with endovascular treatment (EVT).

METHODS

Patients with acute ischemic stroke who underwent successful EVT were enrolled. Plasma d-dimer was measured before and within 6 h after endovascular procedures. Futile recanalization was defined as a modified Rankin Scale score of 3-6 at 90 days of stroke onset. Multivariable logistic regression analyses were performed to determine the relationships between d-dimer and futile recanalization.

RESULTS

Of the 161 enrolled patients, 78 (48.4 %) were classified as futile recanalization. After adjusting for potential confounders, high post-procedural d-dimer level was associated with futile recanalization (odds ratio, 1.25; 95 % CI, 1.05-1.51; P = 0.016). In patients with futile recanalization, change in serum d-dimer levels increased significantly after EVT (P < 0.001). Furthermore, change in d-dimer level after EVT was associated with futile recanalization (odds ratio, 1.33; 95 % CI, 1.11-1.65; P = 0.005) independently.

CONCLUSIONS

High post-procedural plasma d-dimer levels and a significant increase in d-dimer after EVT may predict futile recanalization in patients with acute ischemic stroke.

Thrombus enhancement sign predicts distal embolization in anterior circulation stroke treated with endovascular thrombectomy

BACKGROUND

Distal embolization (DE) is a concerning complication of endovascular treatment (EVT) that is linked to adverse clinical outcomes in acute ischemic stroke (AIS). The thrombus enhancement sign (TES) has been identified as a potential biomarker of occlusion; however, its predictive value for DE remains to be fully clarified.

METHODS

We retrospectively evaluated data of consecutive patients with large vessel occlusion (LVO) in anterior circulation who underwent EVT between January 2020 and December 2023. Each included patient was underwent baseline non-contrast computed tomography (CT) and CT angiography (CTA). We assessed the incidence of DE and its association with clinical and technical outcomes. The association of DE with patient characteristics, thrombus imaging, and composition features was assessed using univariable and multivariable logistic regression.

RESULTS

A total of 308 patients were included in the analysis. Distal embolization occurred in 21.1% (65/308) of patients. Patients with DE had longer recanalization time (58 min vs 46 min; p = 0.002), lower proportion achieving successful reperfusion (86% vs 95%; p = 0.022) and decreased frequency of functional independence (31% vs 45%; p = 0.041). TES was significantly more frequent in the DE group compared to the non-DE group (89% vs 70%, p = 0.001). Histopathological examination revealed that TES-positive thrombi contained a higher fibrin/platelet proportion (50.9% vs 48.2% in TES-negative thrombi, p = 0.009) and fewer erythrocytes (41.7% vs 43.5% in TES-negative thrombi, p = 0.043). In multivariable analysis, TES (OR, 2.76; 95% CI, 1.23-7.10; p = 0.022) was the only independent predictor of DE.

DISCUSSION AND CONCLUSION

Our study demonstrates that distal embolization is a prevalent complication of EVT that hinders full recanalization and favorable outcomes. The presence of TES on baseline CT imaging could serve as a reliable radiologic predictor of distal embolization after EVT.

Mechano-Lysis in Whole Blood Clots: On How Mechanics Affect Clot Lysis, and How Lysis Affects Clot Mechanics

Thromboembolic diseases are a significant cause of mortality and are clinically treated enzymatically with tissue plasminogen activator (tPA). Interestingly, prior studies in fibrin fibers and fibrin gels have demonstrated that thrombolysis may be mechanically sensitive. This study aims to expand mechano-lytic studies to whole blood clots. Furthermore, this study investigates not only how mechanics impacts lysis but also how lysis impacts mechanics. Therefore, clots made from whole human blood are exposed to tPA while the clots are either stretched or unstretched. After, the resulting degree of clot lysis is measured by weighing the clots and by measuring the concentration of D-dimer in the surrounding bath. Additionally, each clot's mechanical properties are measured. This study finds that mechanical stretch accelerates loss in clot weight but does not impact the lysis rate as measured by D-dimer. Moreover, lysis not only removes clot volume but also reduces the remaining clot's stiffness and toughness. In summary, tPA-induced lysis of whole clot appears mechanically insensitive, but stretch reduces clot weight. Furthermore, results show that thrombolysis weakens clot. This suggests that thrombolysis may increase the risk of secondary embolizations but may also ease clot removal during thrombectomy, for example.

Impact of thrombus composition on virtual thrombectomy procedures using human clot analogues mechanical data

Endovascular thrombectomy (EVT) aims at restoring blood flow in case of acute ischemic stroke by removing the thrombus occluding a large cerebral artery. During the procedure with stent-retriever, the thrombus is captured within the device, which is then retrieved, subjecting the thrombus to several forces, potentially leading to its fragmentation. In silico studies, along with mechanical characterisation of thrombi, can enhance our understanding of the EVT, helping the development of new devices and interventional strategies. Our group previously validated a numerical approach to study EVT able to account for thrombus fragmentation. In this study, the same methodology was employed to explore the applicability of the chosen failure criterion to EVT simulations and the impact of thrombus composition on the outcome of the in silico procedure. For the first time, human clot analogues experimental data were applied to this methodology. Clot analogues of three different compositions were tested, and a material model incorporating failure was calibrated, followed by a verification analysis. Finally, the calibrated material model was used to perform EVT simulations, combining the three tested thrombus compositions with three different stent retriever models. The experimental tests confirmed a compression-tension asymmetry in the stress-strain curves, showing decreasing stiffness with increasing the red blood cell (RBC) content. Applying the resulting material models to EVT simulations demonstrated: (i) the dependency of the failure criterion on the thrombus mesh size, (ii) a greater tendency for RBC-rich thrombi to fragment, and (iii) increased difficulty in retrieving RBC-poor thrombi compared to RBC-rich thrombi.

Effect of Proximal Blood Flow Arrest During Endovascular Thrombectomy (ProFATE): A Multicenter, Blinded-End Point, Randomized Clinical Trial

BACKGROUND

The effect of temporary blood flow arrest during endovascular thrombectomy for acute ischemic stroke is uncertain due to the lack of evidence from randomized controlled trials. We aimed to investigate whether temporary blood flow arrest during endovascular thrombectomy using a balloon guide catheter improves intracranial vessel recanalization compared with nonflow arrest.

METHODS

The ProFATE trial (Proximal Blood Flow Arrest During Endovascular Thrombectomy) was a multicenter, randomized, participant- and outcome-blinded trial at 4 thrombectomy centers in the United Kingdom. Adults with acute ischemic stroke due to anterior circulation large vessel occlusion were randomly assigned (1:1) by a central, Web-based program with a minimization algorithm to undergo thrombectomy with temporary proximal blood flow arrest or nonflow arrest during each attempt. The primary outcome was the proportion of participants achieving near-complete/complete vessel recanalization (expanded Thrombolysis in Cerebral Infarction score of 2c or 3) at the end of the thrombectomy procedure, adjudicated by a blinded independent imaging core laboratory. Analyses were performed on the intention-to-treat population, adjusted for age, IV thrombolysis, onset-to-randomization time, Alberta Stroke Program Early CT Score, occlusion site, randomization site, and National Institutes of Health Stroke Scale.

RESULTS

Between October 10, 2021, and June 27, 2023, we recruited 134 participants, of whom 131 participants (mean age, 75 years; 62 [47%] women and 69 [53%] men) were included in the final analysis. Sixty-six participants were allocated to the temporary blood flow arrest group and 65 to the nonflow arrest group. The proportion of participants with an expanded Thrombolysis in Cerebral Infarction 2c/3 score at the end of the endovascular procedure was 74.4% (49/66) in the flow arrest group and 70.8% (46/65) in the nonflow arrest group (adjusted odds ratio, 1.07 [95% CI, 0.45-2.55]; P=0.88). Among the prespecified secondary efficacy outcomes, a lower rate of emboli to a new vascular territory occurred in the blood flow arrest group compared with the nonflow arrest group (1.5% versus 12.3%; adjusted odds ratio, =0.04 [95% CI, 0.01-0.53]; P=0.014) and a higher rate of complete recanalization (expanded Thrombolysis in Cerebral Infarction score, 3) after the first attempt in the flow arrest group versus the nonflow arrest group (33.0% versus 15.3%; adjusted odds ratio, =3.80 [95% CI, 1.40-10.01]; P=0.007). No between-group differences were identified for the remaining procedural or clinical efficacy (modified Rankin Scale at 90 days) or safety outcomes (worsening of the stroke severity at 24 hours, adverse events, symptomatic intracranial hemorrhage, or mortality).

CONCLUSIONS

Among patients presenting with anterior circulation large vessel occlusion acute ischemic stroke, temporary proximal blood flow arrest during endovascular thrombectomy, compared with nonflow arrest, did not significantly improve the near-complete/complete vessel recanalization (expanded Thrombolysis in Cerebral Infarction score, 2c-3) at the end of the procedure. Larger randomized controlled trials are warranted to confirm or refute a clinically significant treatment effect of temporary flow arrest on the functional outcome following endovascular thrombectomy.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05020795.

Multicenter clinical trial evaluating the safety and efficacy of mechanical thrombectomy using the Versi Retriever

BACKGROUND

This study aimed to elucidate the safety and efficacy of mechanical thrombectomy using the Versi Retriever in patients with acute ischemic stroke (AIS).

METHODS

This was a prospective, multicenter, single-arm study conducted at 10 institutes in Japan from December 2018 to March 2021 on mechanical thrombectomy using the Versi Retriever in patients with AIS. The primary efficacy outcome was the modified Rankin scale (mRS) 0-2 at 90 days after the procedure. The primary safety outcome was mortality within 90 days after the procedure.

RESULTS

Fifty-eight patients with a mean age of 72.7 years were enrolled in the study. The primary efficacy outcome of mRS 0-2 at 90 days was 62.0% (95% CI 47.2-75.3%) in patients within 8 hours of stroke onset. The rate of immediate reperfusion of Thrombolysis in Cerebral Infarction (TICI) grade 2b-3 using the Versi Retriever in three passes was 78.0% (64.0-88.5%). The rate of final reperfusion of TICI 2b-3 was 100% (92.9-100%). The primary safety outcome of mortality within 90 days was 8.0% (2.2-19.2%) in patients within 8 hours of AIS onset. The incidence of intracranial hemorrhage within 24 hours was 12.0% (4.5-24.3%) for symptomatic cases and 32.0% (19.5-46.7%) for asymptomatic cases.

CONCLUSION

The Versi Retriever proved to be a safe and effective option for mechanical thrombectomy in patients with AIS.

SOFIA Aspiration System as first-line Technique (SOFAST): a prospective, multicenter study to assess the efficacy and safety of the 6 French SOFIA Flow Plus aspiration catheter for endovascular stroke thrombectomy

BACKGROUND

Mechanical thrombectomy (MT) is the standard of care for acute ischemic stroke (AIS) patients with large vessel occlusion (LVO). The SOFAST study collected clinical evidence on the safety and efficacy of the 6 French SOFIA Flow Plus aspiration catheter (SOFIA 6F) when used as first-line treatment.

METHODS

This was a prospective, multicenter investigation to assess the safety and efficacy of SOFIA 6F used for first-line aspiration. Anterior circulation LVO stroke patients were enrolled. The primary endpoint was the final modified Thrombolysis in Cerebral Infarction (mTICI)≥2b rate. Secondary endpoints included first-pass and first-line mTICI≥2b rates, times from arteriotomy to clot contact and mTICI≥2b, and 90-day modified Rankin Scale (mRS)≤2. First-line and final mTICI scores were adjudicated by an independent imaging core lab. Safety events were assessed by an independent clinical events adjudicator.

RESULTS

A total of 108 patients were enrolled across 12 centers from July 2020 to June 2022. Median age was 67 years, median National Institutes of Health Stroke Scale (NIHSS) was 15.5, and 56.5% of patients received intravenous thrombolytics. At the end of the procedure, 97.2%, 85.2%, and 55.6% of patients achieved mTICI≥2b, ≥2c, and 3, respectively. With SOFIA 6F first-line aspiration, 87.0%, 79.6%, and 52.8% achieved mTICI≥2b, ≥2c, and 3, respectively. After the first pass, 75.0%, 70.4%, and 50.9% achieved mTICI≥2b, ≥2c, and 3, respectively. Median times from arteriotomy to clot contact and successful revascularization were 12 and 17 min, respectively. At 90 days, 66.7% of patients achieved mRS≤2.

CONCLUSIONS

First-line aspiration with SOFIA 6F is safe and effective with high revascularization rates and short procedure times.

Triple Aspiration versus Conventional Aspiration Techniques: A Randomized In Vitro Evaluation

BACKGROUND AND PURPOSE

A single-aspiration maneuver using a large-volume syringe is a common and effective technique for aspiration thrombectomy. Multiple aspiration cycles using large aspiration syringes have been proposed as a means to improve the efficacy over single aspiration. In this study, we sought to investigate the efficacy of a "triple aspiration technique" in which a large-volume syringe is cycled 3 times before catheter retraction during aspiration thrombectomy.

MATERIALS AND METHODS

A 3D-printed adult vasculature was used as a benchtop thrombectomy platform. Fibrin-rich and red blood cell-rich clots were prepared in centrifuge tubes using human plasma, red blood cells, and calcium chloride. Next, clots were placed in the carotid terminus of the model, and the performances of 3 different aspiration techniques-triple syringe, single syringe, and continuous pump aspiration-were compared in a randomized manner (1:1:1). Outcomes of interest included first-pass efficacy (FPE), complete clot removal (final modified TICI 2c/3), the number of thrombectomy attempts to achieve modified TICI 2c/3, vacuum pressure, and distal embolization. The distal emboli were detected using a 70-μm cell strainer placed at the outflow of the model and quantified using an image-processing algorithm. The vacuum pressures were measured using a pressure transducer.

RESULTS

A total of 102 replicates were performed, 34 for each technique. The triple-aspiration technique provided a significantly higher rate of FPE than the syringe and pump aspiration techniques (67.6% versus 41.1%, P = .02). Additionally, the triple-aspiration technique achieved complete clot removal with a significantly lower mean number of thrombectomy attempts compared with single-syringe aspiration (1.2 [SD, 0.5] versus 1.8 [SD, 0.8], P = .005). The triple-aspiration technique generated significantly higher mean vacuum pressure than both the single-syringe and vacuum pump aspiration (28.3 [SD, 0.2] versus 27.2 [SD, 0.3], P = .002 and 26.2 [SD, 0.4], P = .001, respectively). The differences in complete clot removal and distal embolization parameters were not statistically significantly different across the groups.

CONCLUSIONS

Our findings suggest that the triple aspiration technique can improve FPE rates and vacuum pressure in aspiration thrombectomy. Further studies are needed to examine the safety and efficacy of triple aspiration in the clinical setting.

Cyclic Aspiration in Mechanical Thrombectomy: Influencing Factors and Experimental Validation

BACKGROUND AND PURPOSE

Mechanical thrombectomy is a fundamental intervention for acute ischemic stroke treatment. While conventional techniques are effective, cyclic aspiration (CyA) shows potential for better recanalization rates. We aim to investigate factors affecting CyA and compare them with static aspiration (StA).

MATERIALS AND METHODS

StA setup consisted of an aspiration pump connected to pressure transducer. CyA was tested with 5 subsequent iterations: single solenoid valve with air plus saline (i1) or saline alone (i2) as aspiration medium; 2 solenoid valves with air plus saline (i3) as aspiration medium; complete air removal and saline feeding (i4); and pressurized saline feeding (i5). To assess the efficacy of clot ingestion, the pressure transducer was replaced with a distal aspiration catheter. Moderately stiff clot analogs (15 mm) were used to investigate the ingestion quantified as clot relative weight loss. Additionally, the aspiration flow rate was assessed for each setup.

RESULTS

With CyA i1, the amplitude of the achieved negative pressure waves declined with increasing frequencies but progressively increased with each subsequent iteration, achieving a maximum amplitude of 81 kPa for i5 at 1 Hz. Relative clot weight loss was significantly higher with i5 at 5 Hz than with StA (100% versus 37.8%; P = .05). Aspiration flow rate was lower with CyA than with StA (i5 at 5 Hz: 199.8 mL/min versus StA: 311 mL/min; P < .01).

CONCLUSIONS

CyA with the appropriate setup may represent an encouraging innovation in mechanical thrombectomy, offering a promising pathway for improving efficacy in clot ingestion and recanalization. The observed benefits warrant confirmation in a clinical setting.

Iatrogenic emboli during mechanical thrombectomy for acute ischemic stroke: comparison between stent retriever technique and contact aspiration-a retrospective case-control study

BACKGROUND

Mechanical thrombectomy (MT) is an effective treatment for acute ischemic stroke from large vessel occlusion (LVO). While embolization to a new territory (ENT) after MT is well-documented, data on embolization in the same distal territory (EDT) are limited. Achieving modified Treatment In Cerebral Infarction (mTICI) 3 reperfusion presents significant clinical benefits over mTICI 2b/2c, necessitating strategies to reduce both ENT and EDT. Previous studies suggest higher rates of EDTs with contact aspiration compared with stentrievers. However, comprehensive comparison studies in clinical practice are scarce. This study compares the rates of overall clot emboli (OCE) between these MT strategies.

METHODS

A retrospective, multicenter observational study was conducted at four university hospitals in France from January 2015 to November 2019. Adult patients (≥18 years) with acute ischemic stroke due to LVO, treated with either contact aspiration (ADAPT, A Direct Aspiration First Pass Technique) or stentrievers, specifically using the Embotrap device to maintain sample homogeneity, were included. Digital subtraction angiography was used for imaging, with two independent, blinded reviewers assessing OCE post-first MT pass. Propensity score full matching and independent sample testing were employed to evaluate OCE after the first MT pass.

RESULTS

A significant difference in OCE rates was observed between contact aspiration and stentriever techniques, with the stentriever technique resulting in fewer embolic events compared with ADAPT, based on a propensity score analysis that accounts for key confounding factors.

CONCLUSION

A statistically significant reduction in embolic events was observed with the stentriever technique compared with contact aspiration. These results suggest that the stentriever method may offer a safer profile in terms of embolic risk for LVO interventions, and should be considered over contact aspiration when embolic risk is a primary concern, while also considering individual patient factors.

Evaluation of partial resheathing of EmboTrap III using the microcatheter (PREMIER) technique for fibrin-rich hard clots in an in vitro vessel model

Background and purpose

Despite the ongoing advancements in mechanical thrombectomy for large vessel occlusions causing acute ischemic stroke, successful recanalization is not achieved in all patients. One contributing factor is the presence of fibrin-rich hard clots. We proposed a new technique called the PREMIER technique, which aims to retrieve fibrin-rich clots. This study evaluated the efficacy of the PREMIER technique on fibrin-rich and erythrocyte-rich clots by comparing it with the simple use of EmboTrap III in an in vitro vessel model.

Methods

The PREMIER technique involves partially resheathing a fully deployed EmboTrap III (CERENOVUS, Johnson & Johnson Medical Devices, Irvine, California, USA) using a microcatheter to capture and retrieve a hard clot between the inner channel and outer cages of EmboTrap III. We compared recanalization rate of the PREMIER technique with the simple use of EmboTrap III in an in vitro vessel model, occluding the M1 segment with fibrin-rich hard clots (0% erythrocyte composition) and erythrocyte-rich clots (50% erythrocyte composition).

Results

Among the 40 procedures (10 each for the PREMIER technique and the simple use of EmboTrap III for two different clots) for fibrin-rich clots, the PREMIER technique achieved successful recanalization in all 10 cases, with a significantly higher recanalization rate than the EmboTrap III (100% vs. 50%, p = 0.03). For erythrocyte-rich clots, the recanalization rate was not significantly different in the PREMIER technique compared with the simple use of EmboTrap III (80% vs. 70%, p = 1.00).

Conclusion

The PREMIER technique is a novel technique for acute large-vessel occlusions caused by fibrin-rich hard clots that hinders successful recanalization during mechanical thrombectomy.

In vitro evaluation of how the presence of the stent retriever and microcatheter influences aspiration parameters in thrombectomy according to their position inside the aspiration catheter

BACKGROUND

Several variations of the combined thrombectomy technique for acute ischemic stroke using a stent retriever and aspiration catheter have been described. The aim of our study was to assess how the presence of the microcatheter and stent retriever affect the basic aspiration parameters, namely, flow rate and aspiration force, depending on their position within the aspiration catheter.

METHODS

Two experimental set-ups were designed to assess changes in flow rate and aspiration force according to the position of the stent retriever and microcatheter within the aspiration catheter.

RESULTS

The transition of the stent retriever and microcatheter from the distal to proximal position resulted in a progressive increase in the flow rate, but with no impact on aspiration force. Additionally, the size of the stent retriever had no significant effect on flow rate changes and the reduction in flow rate was related to the microcatheter diameter. Negative pressure generated inside the aspiration catheter impacted on its distal segment located beyond the radiopaque marker, thus leading to its partial collapse. As a consequence, the measured aspiration force was lower than the theoretical aspiration force level for all tested aspiration catheters.

CONCLUSIONS

In our experimental model, the position of the stent retriever and microcatheter within the aspirator catheter affected the flow rate, but not the aspiration force. Negative pressure generated within the aspiration catheter appeared to determine a partial collapse of the distal segment that resulted in a less effective aspiration force than the theoretical aspiration force level.

Initial experience with a novel stent-based mechanical thrombectomy device for management of acute myocardial infarction cases with large thrombus burden

BACKGROUND

Patients with acute myocardial infarction (AMI) and large thrombus burden (LTB) still represent a challenge. Afflicted patients have a high morbidity and mortality. Aspiration thrombectomy is often ineffective in those cases. Mechanical thrombectomy devices (MTDs), which are effective for management of ischemic strokes, were recently CE-approved for treatment of thrombotic coronary lesions. Real-world data about their performance in AMI cases with LTB are scarce. This study sought to summarize our early experience with a novel MTD device in this context.

METHODS

We analyzed consecutive patients from the prospective OPTIMISER registry (NCT04988672), who have been managed with the NeVa™ MTD (Vesalio, USA) for AMI with LTB at a tertiary cardiology facility. Outcomes of interest included, among others, periprocedural complications, target lesion failure (TLF), target lesion revascularization (TLR) and target vessel myocardial infarction (TV-MI).

RESULTS

Overall, 15 patients underwent thrombectomy with the NeVa™ device. Thrombectomy was successfully performed in 14 (93%) patients. Final TIMI 3 flow was achieved in 13 (87%) patients, while 2 (13%) patients had TIMI 2 flow. We encountered no relevant periprocedural complications, especially no stroke, stent thrombosis or vessel closure. After a mean follow-up time of 26 ± 2.9 months, 1 (7%) patient presented with TLR due to stent thrombosis (10 months after treatment with the MTD and stenting).

CONCLUSIONS

In AMI patients with LTB, the deployment of the novel NeVa™ MTD seems efficient and safe. Further randomized trials are warranted to assess whether the use of the NeVa™ device in cases with LTB improves procedural and clinical outcomes.

Current Approaches and Methods to Understand Acute Ischemic Stroke Treatment Using Aspiration Thrombectomy

Acute ischemic stroke occurs when a blood clot occludes a cerebral artery. Mechanical interventions, primarily stent retrievers and aspiration thrombectomy, are used currently for removing the occluding clot and restoring blood flow. Aspiration involves using a long catheter to traverse the cerebral vasculature to reach the blood clot, followed by application of suction through the catheter bore. Aspiration is also used in conjunction with other techniques such as stent retrievers and balloon guide catheters. Despite the wide use of aspiration, our physical understanding of the process and the causes of the failure of aspiration to retrieve cerebral clots in certain scenarios is not well understood. Experimental and computational studies can help develop the capability to provide deeper insights into the procedure and enable development of new devices and more effective treatment methods. We recapitulate the aspiration-based thrombectomy techniques in clinical practice and provide a perspective of existing engineering methods for aspiration. We articulate the current knowledge gap in the understanding of aspiration and highlight possible directions for future engineering studies to bridge this gap, help clinical translation of engineering studies, and develop new patient-specific stroke therapy.

Optimal Angiographic Goal and Number of Passes for Octogenarians Undergoing Endovascular Stroke Thrombectomy

BACKGROUND

The optimal recanalization goal and number of endovascular thrombectomy (EVT) passes for elderly patients with large vessel occlusion strokes is unclear.

METHODS

Consecutive patients 80 years or older undergoing EVT were identified from 2016 to 2022 at a single center. Clinical information, procedural details, and modified treatment in cerebral ischemia (mTICI) scores were collected. Primary outcome was modified Rankin scale (mRS) at 90 days. Bivariate and multivariable analyses were conducted to assess associations between mTICI scores, EVT passes, and 90-day outcomes.

RESULTS

One hundred twenty-six patients were identified. At 90 days, mTICI 2b recanalization resulted in high rates of poor outcomes (8.7% functional independence and 60.9% mortality) not significantly different from mTICI 0, 1 or 2a (median mRS 6 vs. 6, P = 0.61). Complete recanalization (mTICI 2c or 3) led to significantly better mRS outcomes at 90 days compared to mTICI 2b (median mRS 4 vs. 6, adjusted P = 0.038), with 26.8% functional independence and 37.8% mortality. In multivariable analysis, complete recanalization was significantly associated with better 90-day outcomes than mTICI 2b or lower recanalization (odds ratio 4.24 [95% Confidence interval 1.46-12.3]; P = 0.002), while the number of passes was not independently associated with worse outcomes (P = 0.98).

CONCLUSIONS

For octogenarians, mTICI 2b recanalization yields limited clinical benefit and results in poor 90-day outcomes. In contrast, complete recanalization is independently associated with significantly better outcomes. Thus, once the decision is made to pursue EVT in the elderly, mTICI 2c or better recanalization should be the angiographic goal. Providers should not withhold thrombectomy passes based on age alone.

Intra-arterial tenecteplase during thrombectomy for acute stroke (BRETIS-TNK II): rationale and design

BACKGROUND

Our recent pilot study suggests intra-arterial tenecteplase (TNK) during the first pass of endovascular treatment (EVT) seems safe, may increase first-pass reperfusion and good outcome in acute ischaemic stroke (AIS) patients with large-vessel occlusion (LVO).

AIMS

To determine the efficacy and safety of intra-arterial TNK administration during EVT in AIS-LVO patients presenting up to 24 hours from symptom onset.

SAMPLE SIZE ESTIMATES

A maximum of 380 patients are required to test the superiority hypothesis with 80% power according to a two-side 0.05 level of significance, stratified by age, gender, baseline systolic blood pressure, prestroke modified Rankin Scale (mRS), baseline National Institute of Health stroke scale, baseline ASPECTS, time from onset to groin puncture, intravenous thrombolysis before EVT, stroke territory and stroke aetiology.

DESIGN

Intra-arterial TNK during thrombectomy for acute stroke (BRETIS-TNK II) study is a prospective, randomised, adaptive enrichment, open-label, blinded end point, multicentre study. Eligible AIS-LVO patients are randomly assigned into the experimental group and control group with a ratio of 1:1. The experimental group will be treated with intra-arterial infusion of TNK during EVT. The control group will be treated with standard EVT.

OUTCOME

The primary end point is a favourable outcome, defined as an mRS score of 0-2 at 90 days. The primary safety end point is symptomatic intracranial haemorrhage within 48 hours, which is defined as an increase in the National Institutes of Health Stroke Scale score of ≥4 points as a result of the intracranial haemorrhage.

CONCLUSIONS

The results of BRETIS-TNK II will provide evidence for the efficacy and safety of intra-arterial TNK administration during EVT in AIS patients with LVO.

Comparison between transradial and transfemoral mechanical thrombectomy for ICA and M1 occlusions: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

The role for the transradial approach for mechanical thrombectomy is controversial. We sought to compare transradial and transfemoral mechanical thrombectomy in a large multicenter database of acute ischemic stroke.

METHODS

The prospectively maintained Stroke Thrombectomy and Aneurysm Registry (STAR) was reviewed for patients who underwent mechanical thrombectomy for an internal carotid artery (ICA) or middle cerebral artery M1 occlusion. Multivariate regression analyses were performed to assess outcomes including reperfusion time, symptomatic intracerebral hemorrhage (ICH), distal embolization, and functional outcomes.

RESULTS

A total of 2258 cases, 1976 via the transfemoral approach and 282 via the transradial approach, were included. Radial access was associated with shorter reperfusion time (34.1 min vs 43.6 min, P=0.001) with similar rates of Thrombolysis in Cerebral Infarction (TICI) 2B or greater reperfusion (87.9% vs 88.1%, P=0.246). Patients treated via a transradial approach were more likely to achieve at least TICI 2C (59.6% vs 54.7%, P=0.001) and TICI 3 reperfusion (50.0% vs 46.2%, P=0.001), and had shorter lengths of stay (mean 9.2 days vs 10.2, P<0.001). Patients treated transradially had a lower rate of symptomatic ICH (8.0% vs 9.4%, P=0.047) but a higher rate of distal embolization (23.0% vs 7.1%, P<0.001). There were no significant differences in functional outcome at 90 days between the two groups.

CONCLUSIONS

Radial and femoral thrombectomy resulted in similar clinical outcomes. In multivariate analysis, the radial approach had improved revascularization rates, fewer cases of symptomatic ICH, and faster reperfusion times, but higher rates of distal emboli. Further studies on the optimal approach are necessary based on patient and disease characteristics.

Effects of intravenous thrombolysis on stent retriever and aspiration thrombectomy outcomes: a systematic review and meta-analysis of the randomized controlled trials

BACKGROUND

Risks and benefits of intravenous thrombolysis (IVT) in patients undergoing mechanical thrombectomy (MT) have been a topic of interest. However, IVT's specific effects on stent retriever (SR) and aspiration thrombectomy (ASP) outcomes remain largely unexplored. In this meta-analysis, we aimed to investigate the effects of IVT on SR and ASP thrombectomy outcomes.

METHODS

In accordance with PRISMA guidelines, a systematic literature review was conducted using Medline, Embase, Scopus, Web of Science, and Cochrane Center of Clinical Trials databases. Outcomes of interest included successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b), modified first pass efficacy (mFPE), functional independence (modified Rankin Scale (mRS) ≤2), symptomatic intracranial hemorrhage (sICH), and embolization to new territories (ENT).

RESULTS

Four randomized controlled trials with 1176 patients were included. SR and ASP resulted in similar mTICI ≥2b, mFPE, and mRS 0-2 rates in patients with and without IVT administration. SR without IVT was associated with a significantly lower rate of mFPE compared with the SR+IVT (RR 0.85, 95% CI 0.74 to 0.97). Furthermore, ASP without IVT resulted in a lower rate of mRS 0-2 than the ASP+IVT with a strong trend towards significance (RR 0.78, 95% CI 0.60 to 1.01). Finally, bridging therapy did not increase sICH and ENT rates after ASP or SR thrombectomy.

CONCLUSIONS

Our findings suggest that SR and ASP thrombectomy have comparable safety and efficacy profiles, regardless of prior IVT administration. Additionally, our results indicate that the addition of IVT may improve certain efficacy outcomes based on the employed first-line MT technique.

Pre-navigation balloon technique: Distal emboli protection during stent retriever thrombectomy

OBJECTIVE

During stent retriever thrombectomy, a balloon guide catheter reduces distal emboli and consequently improves clinical outcomes. Because balloons are usually used before stent retrieval, these can affect the thrombus including the distal emboli while performing microcatheter navigation. This study aimed to evaluate the usefulness and safety of the pre-navigation balloon technique during microcatheter and microwire navigation.

METHODS

Patients who underwent stent retriever thrombectomy secondary to an anterior circulation large-artery occlusion were retrospectively evaluated. The pre-navigation balloon technique was used, and the number of retrievals, procedure time, final recanalization, presence of distal emboli, first-pass effect (FPE), symptomatic intracranial hemorrhage including procedure-related complications, and clinical outcomes at 3 months were evaluated.

RESULTS

In total 123 patients were analyzed, and occurrence of distal emboli was lesser in the pre-navigation balloon than in the non-preballoon group (4.4% vs. 11.5%, p = 0.02). No statistical difference was found in successful recanalization, mortality, and procedure-related complications. Moreover, the pre-navigation balloon group had a higher FPE than the non-balloon group (37.8% vs. 20.5%, p = 0.004). Although no statistical difference was found in the pre-navigation balloon group, a trend toward a higher rate of good clinical outcomes was observed (mRS 0-2 at 3 months, 55.6% vs. 48.7%, p = 0.09). For ICA occlusion(n = 35), significant effects were seen in decreasing distal embolism (0(0%) vs 3(16%), p = 0.01), increasing FPE (8(50%) vs 6(32%), p = 0.003), and improving clinical outcomes (mRS 0-2 at 3 months, 9(56%) vs 7(37%), p = 0.03) in the pre-navigation balloon group. In the multivariate analysis, lesser distal embolism (0.91 [0.80-1.00], p = 0.02), higher successful recanalization (3.52 [1.11-7.03], p = 0.016), and higher FPE (3.17 [1.83-7.37], p = 0.001) secondary to the procedure was a predictor of favorable clinical outcomes.

CONCLUSIONS

The pre-navigation balloon technique significantly reduced occurrence of distal embolism and increased the FPE.

In vitro models for the experimental evaluation of mechanical thrombectomy devices in acute ischemic stroke

Mechanical thrombectomy has become an important method for the treatment of acute ischemic stroke for large vessel occlusions. The current hotspots of mechanical thrombectomy are optimizing the treatment methods, improving the recanalization rate and reducing complications. The in vitro model has become a common and convenient method for mechanical thrombectomy research. This review summarizes the in vitro model in the following aspects: the preparation of clot analogues; the experimental platform; the application of the in vitro model in the testing of thrombectomy devices; and the advantages, limitations and future trends of the in vitro experimental model. This review describes the characteristics and applications of the in vitro experimental model with the hope that the in vitro experimental model will be further improved and play a more effective role in the study of mechanical thrombectomy.

Clinical Benefit of First-Pass Recanalization Is Time-Dependent in Endovascular Treatment of Acute Ischemic Stroke

Clinical benefit can be time-dependent even after first-pass recanalization (FPR) in endovascular treatment of acute stroke. This study aimed to evaluate the association between favorable outcome and FPR under a specific time frame. Patients who underwent mechanical thrombectomy were retrospectively reviewed. Recanalization status was categorized into four groups based on FPR and dichotomized time from groin puncture to recanalization (P-to-R time). Favorable outcomes were compared between groups. A total of 458 patients were included. As the cutoff of P-to-R time for favorable outcome was 30 min, recanalization status was categorized into FPR (+) with a P-to-R time ≤ 30 min (Group 1), FPR (-) with a P-to-R time ≤ 30 min (Group 2), FPR (+) with a P-to-R time > 30 min (Group 3), and FPR (-) with a P-to-R time > 30 min (Group 4). Favorable outcomes in Group 3 (37.5%) were significantly less frequent than those in Group 1 (60.4%, p = 0.029) and Group 2 (59.5%, p = 0.033) but were not significantly different from those in Group 4 (35.7%, p = 0.903). Compared to Group 1, Group 3 (adjusted odds ratio, 0.30 [95% confidence interval, 0.12-0.76]; p = 0.011) and Group 4 (0.25 [0.14-0.48]; p < 0.001) were adversely associated with favorable outcomes. FPR was associated with functional outcome in a time-dependent manner. Even for patients who have achieved FPR, their functional outcome might not be favorable if the P-to-R time is >30 min.

Peri-procedural decrease in hemoglobin following mechanical thrombectomy for ischemic stroke

BACKGROUND

Peri-procedural blood loss and hemodilution occur in patients undergoing mechanical thrombectomy (MT) for ischemic stroke; however, its relationships with thrombectomy passes, procedure times, and clinical outcomes are unknown.

METHODS

Consecutive patients undergoing MT for anterior circulation large-vessel occlusion ischemic strokes were identified at a Comprehensive Stroke Center. Clinical information, modified treatment in cerebral ischemia (mTICI) scores, and modified Rankin Scores (mRS) at 90 days were prospectively collected from 2012 to 2021. Hemoglobin measurements before and after MTs were collected retrospectively via chart review, and changes were quantified. Patients with new-onset severe anemia (defined as post-MT hemoglobin less than 10g/dL) were identified. Modified Rankin scale (mRS) at 90 days was used to measure clinical outcomes.

RESULTS

Four-hundred and forty-five patients were identified. Hemoglobin decreased 1.27 ± 1.05 g/dL after MT on average. Greater number of thrombectomy passes and longer procedure times were associated with larger decreases in hemoglobin (p < 0.001 and p = 0.002, respectively). 11.5% (51 of 445) of patients had new-onset severe anemia, and this incidence was significantly higher with more thrombectomy passes (6.4% for one pass, 11.9% for two passes, and 17.4% for three or more passes; p = 0.010). In multivariable analyses, new-onset severe anemia was associated with significantly higher odds of 90-day poor outcomes (mRS 3-6, OR 2.70 [95%CI 1.12-6.51], p = 0.027) and death (OR 2.73 [95%CI 1.06-7.04], p = 0.037) compared to mild post-MT anemia.

CONCLUSIONS

More thrombectomy passes and longer procedure times were significantly associated with larger peri-procedural decreases in hemoglobin. Patients with new-onset hemoglobin less than 10 g/dL are at risk of poor outcomes.

Impact of vessel tortuosity and radiological thrombus characteristics on the choice of first-line thrombectomy strategy: Results from the ESCAPE-NA1 trial

INTRODUCTION

Despite improvements in device technology, only one-third of stroke patients undergoing endovascular thrombectomy (EVT) achieve first-pass effect (FPE). We investigated the effect of arterial tortuosity and thrombus characteristics on the relationship between first-line EVT strategy and angiographic outcomes.

PATIENTS AND METHODS

Patients with thin-slice baseline CT-angiography from the ESCAPE-NA1 trial (Efficacy and safety of nerinetide for the treatment of acute ischemic stroke) were included. Tortuosity was estimated using the tortuosity index extracted from catheter pathway, and radiological thrombus characteristics were length, non-contrast density, perviousness and hyperdense artery sign. We assessed the association of first-line EVT strategy (stent-retriever [SR] versus contact aspiration [CA] versus combined SR+CA) with FPE (eTICI score 2c/3 after one pass), final eTICI 2b/3, number of passes and procedure duration using multivariable regression. Interaction of tortuosity and thrombus characteristics with first-line technique were assessed using interaction terms.

RESULTS

Among 520 included patients, SR as a first-line modality was used in 165 (31.7%) patients, CA in 132 (25.4%), and combined SR+CA in 223 (42.9%). FPE was observed in 166 patients (31.9%). First-line strategy was not associated with FPE. Tortuosity had a significant effect on FPE only in the CA group (aOR = 0.90 [95% CI 0.83-0.98]) compared with stent-retrievers and combined first-line approach (p interaction = 0.03). There was an interaction between thrombus length and first-line strategy for number of passes (p interaction = 0.04). Longer thrombi were associated with higher number of passes only in the CA group (acOR 1.03 [95% CI 1.00-1.06]).

CONCLUSION

Our study suggests that vessel tortuosity and longer thrombi may negatively affect the performance of first-line contact aspiration catheters in acute stroke patients undergoing EVT.

Effect of proximal blood flow arrest during endovascular thrombectomy (ProFATE): Study protocol for a multicentre randomised controlled trial

BACKGROUND

Observational studies have demonstrated improved outcomes with the adjunctive use of balloon guide catheters (BGC) during endovascular thrombectomy (EVT) for anterior circulation acute ischaemic stroke (AIS). However, the lack of high-level evidence and global practice heterogeneity justifies a randomised controlled trial (RCT) to investigate the effect of transient proximal blood flow arrest on the procedural and clinical outcomes of patients with AIS following EVT.

HYPOTHESIS

Proximal blood flow arrest in the cervical internal carotid artery during EVT for proximal large vessel occlusion is superior to no flow arrest in achieving complete vessel recanalisation.

METHODS

ProFATE is an investigator-initiated, pragmatic, multicentre RCT with blinding of participants and outcome assessment. An estimated 124 participants with an anterior circulation AIS due to large vessel occlusion, an NIHSS of ⩾2, ASPECTS ⩾ 5 and eligible for EVT using a first-line combined technique (contact aspiration and stent retriever) or contact aspiration only will be randomised (1:1) to receive BGC balloon inflation or no inflation during EVT.

OUTCOMES

The primary outcome is the proportion of patients achieving near-complete/complete vessel recanalisation (eTICI 2c-3) at the end of the EVT procedure. Secondary outcomes include the functional outcome (modified Rankin Scale at 90 days), new or distal vascular territory clot embolisation rate, near-complete/complete recanalisation after the first pass, symptomatic intracranial haemorrhage, procedure-related complications and death at 90 days.

DISCUSSION

This is the first RCT to investigate the effect of proximal blood flow arrest during EVT using a BGC on the procedural and clinical outcomes of patients with AIS due to large vessel occlusion.

Distal medium vessel occlusions in acute ischaemic stroke - Stent retriever versus direct aspiration: A systematic review and meta-analysis

BACKGROUND

Acute ischaemic stroke due to distal medium vessel occlusion (AIS-DMVO) causes significant morbidity. Endovascular thrombectomy advancement has made treating AIS-DMVO with stent retrievers (SR) and aspiration catheters (AC) possible, however the optimal technique remains unknown. We performed a systematic review and meta-analysis to investigate the efficacy and safety of SR use compared to purely AC use in patients with AIS-DMVO.

METHODS

We systematically searched PubMed, Cochrane Library and EMBASE, from inception to 2nd September 2022, for studies comparing SR or primary combined (SR/PC) against AC in AIS-DMVO. We adopted the Distal Thrombectomy Summit Group's definition of DMVO. Efficacy outcomes were functional independence (modified Rankin Scale (mRS) 0-2 at 90 days), first pass effect (modified Thrombolysis in Cerebral Infarction scale (mTICI) 2c-3 or expanded Thrombolysis in Cerebral Infarction scale (eTICI) 2c-3 at first pass), successful final recanalisation (mTICI or eTICI 2b-3), and excellent final recanalisation (mTICI or eTICI 2c-3). Safety outcomes were symptomatic intracranial haemorrhage (sICH) and 90-day mortality.

RESULTS

12 cohort studies and 1 randomised-controlled trial were included, involving 1881 patients with 1274 receiving SR/PC and 607 receiving AC only. SR/PC achieved higher odds of functional independence (odds ratio (OR) 1.33, 95% confidence interval (CI) 1.06-1.67) and lower odds of mortality (OR 0.69, 95% CI 0.50-0.94) than AC. Odds of successful/excellent recanalisation and sICH were similar between both groups. Stratified to compare only SR and only AC, the use of only SR, achieved significantly higher odds of successful recanalisation as compared to only AC (OR 1.80, 95% CI 1.17-2.78).

CONCLUSION

There is potential for efficacy and safety benefits in SR/PC use as compared to AC only in AIS-DMVO. Further trials are necessary to validate the efficacy and safety of SR use in AIS-DMVO.

CT-based thrombus radiomics nomogram for predicting secondary embolization during mechanical thrombectomy for large vessel occlusion

Background and aims

Secondary embolization (SE) during mechanical thrombectomy (MT) for cerebral large vessel occlusion (LVO) could reduce the anterior blood flow and worsen clinical outcomes. The current SE prediction tools have limited accuracy. In this study, we aimed to develop a nomogram to predict SE following MT for LVO based on clinical features and radiomics extracted from computed tomography (CT) images.

Materials and methods

A total of 61 patients with LVO stroke treated by MT at Beijing Hospital were included in this retrospective study, of whom 27 developed SE during the MT procedure. The patients were randomly divided (7:3) into training (n = 42) and testing (n = 19) cohorts. The thrombus radiomics features were extracted from the pre-interventional thin-slice CT images, and the conventional clinical and radiological indicators associated with SE were recorded. A support vector machine (SVM) learning model with 5-fold cross-verification was used to obtain the radiomics and clinical signatures. For both signatures, a prediction nomogram for SE was constructed. The signatures were then combined using the logistic regression analysis to construct a combined clinical radiomics nomogram.

Results

In the training cohort, the area under the receiver operating characteristic curve (AUC) of the nomograms was 0.963 for the combined model, 0.911 for the radiomics, and 0.891 for the clinical model. Following validation, the AUCs were 0.762 for the combined model, 0.714 for the radiomics model, and 0.637 for the clinical model. The combined clinical and radiomics nomogram had the best prediction accuracy in both the training and test cohort.

Conclusion

This nomogram could be used to optimize the surgical MT procedure for LVO based on the risk of developing SE.

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.

Initial Experience Using the New pHLO 0.072-inch Large-Bore Catheter for Direct Aspiration Thrombectomy in Acute Ischemic Stroke

PURPOSE

A direct aspiration, first pass technique (ADAPT) has been introduced as a rapid and safe thrombectomy strategy in patients with intracranial large vessel occlusion (LVO). The aim of the study is to determine the technical feasibility, safety, and functional outcome of ADAPT using the newly released large bore pHLO 0.072-inch aspiration catheter (AC; Phenox).

MATERIALS AND METHODS

We performed a retrospective analysis of data collected prospectively (October 2019-November 2021) from 2 comprehensive stroke centers. Accessibility of the thrombus, vascular recanalization, time to recanalization, and procedure-related complications were evaluated. National Institutes of Health stroke scale scores at presentation and discharge and the modified Rankin scale (mRS) score at 90 days post-procedure were recorded.

RESULTS

Twenty-five patients (14 female, 11 male) with occlusions of the anterior circulation were treated. In 84% of cases, ADAPT led to successful recanalization with a median procedure time of 28 minutes. In the remaining cases, successful recanalization required (to a total of 96%; modified thrombolysis in cerebral infarction score 2b/3) the use of stent retrievers. No AC-related complications were reported. Other complications included distal migration of the thrombus, requiring a stent-retriever, and symptomatic PH2 hemorrhage in 16% and 4%, respectively. After 3 months, 52% of the patients had mRS scores of 0-2 with an overall mortality rate of 20%.

CONCLUSION

Results from our retrospective case series revealed that thrombectomy of LVOs with pHLO AC is safe and effective in cases of large-vessel ischemic stroke. Rates of complete or near-complete recanalization after the first pass with this method might be used as a new benchmark in future trials.

Successful reperfusion in relation to the number of passes: comparing outcomes of first pass expanded Treatment In Cerebral Ischemia (eTICI) 2B with multiple-pass eTICI 3

BACKGROUND

Higher expanded Treatment In Cerebral Ischemia (eTICI) reperfusion scores after endovascular treatment (EVT) are associated with better outcomes. However, the influence of the number of passes on this association is unclear. We aimed to compare outcomes of single-pass good reperfusion (eTICI 2B) with multiple-pass excellent/complete reperfusion (eTICI 2C/3) in daily clinical practice.

METHODS

We compared outcomes of patients in the MR CLEAN Registry with good reperfusion (eTICI 2B) in a single pass to those with excellent/complete reperfusion (eTICI 2C/3) in multiple passes. Regression models were used to investigate the association of single-pass eTICI 2B versus multiple-pass eTICI 2C/3 reperfusion with 90-day functional outcome (modified Rankin Scale (mRS)), functional independence (mRS 0-2), per-procedural complications and safety outcomes.

RESULTS

We included 699 patients: 178 patients with single-pass eTICI 2B, and 242 and 279 patients with eTICI 2C/3 after 2 and ≥3 passes, respectively. Patients with eTICI 2C/3 after 2 or ≥3 passes did not achieve significantly better functional outcomes compared with patients with single-pass eTICI 2B (adjusted common OR (acOR) 1.06, 95% CI 0.75 to 1.50 and acOR 0.88, 95% CI 0.74 to 1.05 for 90-day mRS, and adjusted OR (aOR) 1.24, 95% CI 0.78 to 1.97 and aOR 0.79, 95% CI 0.52 to 1.22 for functional independence).

CONCLUSIONS

Our results did not show better outcomes for patients who achieved eTICI 2C/3 in multiple, that is, two or more, passes when compared with patients with single-pass eTICI 2B. However, this concerns observational data. Further research is necessary to investigate the per-pass effect in relation to reperfusion and functional outcome.

Case report: Utilization and efficacy of large-bore catheters in mechanical thrombectomies

Thrombotic strokes are caused by occlusion of flow in a blood vessel by a clot or thrombus, resulting in disruption of oxygen and nutrients to the brain that can result in neurological deficits. There are many devices now available for safe and effective removal of thrombi from large blood vessels. This report focuses on the Zoom 0.088" large-bore catheter, which has the potential to be navigated into a large vessel for thrombus removal via aspiration, and weigh the risks and benefits of its utilization in thrombectomy patients. In this case, we discuss the use of this device for thrombectomy of a left M1 middle cerebral artery occlusion that resulted in a distal left MCA dissection and eventual loss of access to the site of the thrombus. Ultimately, the patient died from a large stroke in the left MCA territory. In light of this occurrence, we seek to explore the utility and feasibility of large-bore catheters and their risks in thrombectomy candidates.

Intra-arterial tenecteplase is safe and may improve the first-pass recanalization for acute ischemic stroke with large-artery atherosclerosis: the BRETIS-TNK trial

Background and purpose

The first-pass recanalization of endovascular treatment (EVT) is closely correlated with clinical outcome of patients with large vessel occlusion (LVO) stroke. The aim of the study was to explore whether intra-arterial tenecteplase (TNK) during the first pass of EVT can increase first-pass successful reperfusion and improve the neurological outcome in AIS-LVO patients.

Materials and methods

The BRETIS-TNK trial (ClinicalTrials.gov Identifier: NCT04202458) was a prospective, single-arm, single center study. Twenty-six eligible AIS-LVO patients with large-artery atherosclerosis etiology were consecutively enrolled from December 2019 to November 2021. Intra-arterial TNK (4 mg) after microcatheter navigation through the clot was administered, followed by TNK (0.4  mg/min) given continuously for 20  min after the first retrieval attempt of EVT without confirmation of the reperfusion status by DSA. The 50 control patients comprised of a historical cohort before the BRETIS-TNK trial (from March 2015 to November 2019). Successful reperfusion was defined as modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b.

Results

The first-pass successful reperfusion rate was higher in the BRETIS-TNK vs. control group (53.8% vs. 36%, p = 0.14), and the difference became statistically significant after propensity score matching (53.8% vs. 23.1%, p = 0.03). There was no difference in symptomatic intracranial hemorrhage between the BRETIS-TNK and control groups (7.7% vs. 10.0%, p = 0.92). There was a trend toward higher proportion of functional independence at 90 days in the BRETIS-TNK comparing with the control group (50% vs. 32%, p = 0.11).

Conclusion

This is the first study to report that intra-arterial TNK during the first pass of EVT seems safe and feasible in AIS-LVO patients.

Mild and moderate cardioembolic stroke patients may benefit more from direct mechanical thrombectomy than bridging therapy: A subgroup analysis of a randomized clinical trial (DIRECT-MT)

Background

The benefit of intravenous alteplase before endovascular thrombectomy is unclear in patients with acute cardioembolic stroke.

Methods

We collected cardioembolic (CE) stroke patient data from the multicentre randomized clinical trial of Direct Intra-arterial Thrombectomy to Revascularize Acute Ischaemic Stroke Patients with Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals (DIRECT-MT). The primary outcome was the 90-day modified Rankin Scale (mRS) score. Five subgroups of cardioembolic stroke patients were analyzed. A multivariable ordinal logistic regression analysis analyzed the difference in the primary outcome between the direct mechanical thrombectomy (MT) and bridging therapy groups. An interaction term was entered into the model to test for subgroup interaction. The DIRECT-MT trial is registered with clinicaltrials.gov Identifier: NCT03469206.

Results

A total of 290 CE stroke patients from the DIRECT-MT trial were enrolled in this study: 146 patients in the direct MT group and 144 patients in the bridging therapy group. No difference between the two treatment groups in the primary outcome was found (adjusted common odds ratio, 1.218; 95% confidence interval, 0.806 to 1.841; P = 0.34). In the subgroup analysis, CE stroke patients with an NIHSS ≤ 15 in the direct MT group were associated with better outcomes (47 vs. 53, acOR, 3.14 [1.497, 6.585]) and lower mortality (47 vs. 53, aOR, 0.16 [0.026, 0.986]) than those in the bridging therapy group, while there were no significant differences between the two treatment groups in the outcome and mortality of CE stroke patients with an NIHSS >15.

Conclusion

Mild and moderate cardioembolic stroke patients may benefit more from direct mechanical thrombectomy than bridging therapy. This need to be confirmed by further prospective studies in a larger number of patients.

Support and guide performance comparison of balloon guide catheters

Background:

Several types of balloon guide catheters (BGCs) are used in mechanical thrombus retrieval. However, direct comparisons of their supporting and guiding performance have not been reported. We compared the supporting and guiding performance of the Branchor, Flowgate, and Optimo BGCs using a type 3 aorta artificial vascular model.

Methods:

An inner catheter was pushed into the artificial vascular model using a linear actuator for the supporting performance evaluation. A previously placed BGC in the internal carotid artery was then intentionally caused to slip. Supporting performance was evaluated by measuring the distance the BGC slipped and generated maximum resistance during Inner catheter insertion. For the guiding performance experiment, a linear actuator was used to guide the BGC into the internal carotid artery of the artificial vessel model. The guiding performance was evaluated by measuring the distance reached by the BGC, maximum resistance generated during insertion of the guiding catheter, and distance the inner catheter slipped. Each experiment was replicated 5 times.

Results:

No statistically significant differences were observed in the results of the five supporting performance experiments. However, the results of the first and second experiments suggested that the Optimo offers better supporting performance. In the guiding performance experiment, significant differences were observed, suggesting that the Branchor and Flowgate have superior guiding performance in comparison with the Optimo.

Conclusion:

The Optimo offered superior supporting performance, while the Branchor and Flowgate showed better guiding performance than the Optimo.

Clot Morphology in Acute Ischemic Stroke Decision Making

Stroke is a leading cause of death and disability in the world, and the provision of reperfusion therapy and endovascular therapy, in particular, have revolutionized the treatment of patients with stroke and opened opportunities to look at brain clots retrieved after the procedure. The use of histopathology and molecular profiling of clots is of growing research and clinical interest. However, its clinical implications and incorporation within stroke workflows remain suboptimal. Recent studies have indicated that the study of brain clots may inform the mechanism of stroke and hence guide treatment decision-making in select groups of patients, especially patients without a defined cause or known mechanism. This article provides a comprehensive overview of various clot histopathological examinations in acute stroke-care settings, their clinical utility, and existing gaps and opportunities for further research. We also provide targeted recommendations to improve clot analysis workflow, hence standardizing its incorporation into clinical practice.

What You Always Wanted to Know about Endovascular Therapy in Acute Ischemic Stroke but Never Dared to Ask: A Comprehensive Review

In 2015, mechanical thrombectomy (MT) in combination with intravenous thrombolysis was demonstrated to be superior to best medical treatment alone in patients with anterior circulation stroke. This finding resulted in an unprecedented boost in endovascular stroke therapy, and MT became widely available. MT was initially approved for patients presenting with large vessel occlusion in the anterior circulation (intracranial internal carotid artery or proximal middle cerebral artery) within a 6-hour time window. Eventually, it was shown to be beneficial in a broader group of patients, including those without known symptom-onset, wake-up stroke, or patients with posterior circulation stroke. Technical developments and the implementation of novel thrombectomy devices further facilitated endovascular recanalization for acute ischemic stroke. However, some aspects remain controversial. Is MT suitable for medium or very distal vessel occlusions? Should emergency stenting be performed for symptomatic stenosis or recurrent occlusion? How should patients with large vessel occlusion without disabling symptoms be treated? Do certain patients benefit from MT without intravenous thrombolysis? In the era of personalized decision-making, some of these questions require an individualized approach based on comorbidities, imaging criteria, and the severity or duration of symptoms. Despite its successful development in the past decade, endovascular stroke therapy will remain a challenging and fascinating field in the years to come. This review aims to provide an overview of patient selection, and the indications for and execution of MT in patients with acute ischemic stroke.

Cavitation-assisted sonothrombolysis by asymmetrical nanostars for accelerated thrombolysis

Sonothrombolysis with recombinant tissue plasminogen activator (rtPA) and microbubbles has been widely studied to enhance thrombolytic potential. Here, we report different sonothrombolysis strategy in nanoparticles using microbubbles cavitation. We found that different particles in shape exhibited different reactivity toward the cavitation, leading to a distinct sonothrombolytic potential. Two different gold nanoparticles in shape were functionalized with the rtPA: rtPA-functionalized gold nanospheres (NPt) and gold nanostars (NSt). NPt could not accelerate the thrombolytic potential with a sole acoustic stimulus. Importantly, NSt enhanced the potential with acoustic stimulus and microbubble-mediated cavitation, while NPt were not reactive to cavitation. Coadministration of NSt and microbubbles resulted in a dramatic reduction of the infarcts in a photothrombotic model and recovery in the cerebral blood flow. Given the synergistic effect and in vivo feasibility of this strategy, cavitation-assisted sonothrombolysis by asymmetrical NSt might be useful for treating acute ischemic stroke.

Age and composition of the thrombus retrieved by mechanical thrombectomy from patients with acute ischemic stroke are associated with revascularization and clinical outcomes

INTRODUCTION

Understanding the composition of stroke thrombi retrieved by mechanical thrombectomy is essential to clarify the pathogenesis of stroke. However, it is difficult to evaluate thrombus composition precisely and objectively. Immunohistochemical staining was used to evaluate thrombus composition and age.

MATERIALS AND METHODS

Consecutive thrombi (n = 108) retrieved from patients who underwent mechanical thrombectomy for acute large-vessel ischemic stroke were retrospectively analyzed. Lytic features of granulocytes and CD163 were estimated as indicators of the age of the cardioembolic (CE) thrombus.

RESULTS

The stroke subtypes were as follows: CE, 74 cases; large artery atherosclerosis, 11; undetermined etiology, 12; and other determined etiology, 11. There were no statistical differences in thrombi composition according to stroke subtypes. The fibrin area was positively correlated with the red blood cell (RBC) and platelet areas. The following analysis was performed using CE only. Regarding age, the thrombus was judged as fresh in 30.0 % and older in 70.0 % based on the lytic features. The RBC areas of older thrombi were smaller than those of fresh thrombi. The puncture-to-reperfusion time of older thrombi was longer than that of fresh thrombi. Platelet-rich thrombi were associated with a greater number of maneuvers, a smaller prevalence of TICI 3, and unfavorable functional outcomes compared to platelet-poor thrombi. The number of CD163 positive cells in thrombi with anticoagulants was higher than in those without anticoagulants.

CONCLUSION

Thrombus composition correlated with revascularization and clinical outcomes. The composition of an acute ischemic thrombus may reflect the pathophysiology of stroke and influence treatment efficacy.

Safety of Sheathless Transradial Balloon Guide Catheter Placement for Acute Stroke Thrombectomy

BACKGROUND

Transradial access has been described for mechanical thrombectomy in acute stroke, and proximal balloon occlusion has been shown to improve recanalization and outcomes. However, sheathed access requires a larger total catheter diameter at the access site. We aimed to characterize the safety of sheathless transradial balloon guide catheter use in acute stroke intervention.

METHODS

Consecutive patients who underwent sheathless right-sided transradial access for thrombectomy with a balloon guide catheter were identified in a prospectively collected dataset from 2019 to 2021. Demographics, procedure details, and short-term outcomes were collected and reported with descriptive statistics.

RESULTS

A total of 48 patients (20 women) with a mean age of 72.3 years were identified. Of patients, 56.3% had occlusions in the left-sided circulation; 35 (72.9%) had M1 occlusions, 7 (14.6%) had M2 occlusions, and 6 (12.5%) had internal carotid artery occlusions. Tissue plasminogen activator was administered to 16 (33.3%) patients. Five (10.4%) patients underwent intraprocedural carotid stenting. The cohort had successful reperfusion after a median of 1 (interquartile range: 1, 2) pass. Median time from access to recanalization was 31 (interquartile range: 25, 53) minutes. A postprocedural Thrombolysis In Cerebral Infarction score of ≥2b was achieved in 46 (95.8%) patients. Five patients had wrist access site hematomas. All hematomas resolved with warm compresses, and no further intervention was required.

CONCLUSIONS

Sheathless radial access using a balloon guide catheter may be safely performed for acute ischemic stroke with excellent radiographic outcomes. Further investigation is warranted to evaluate the comparative effectiveness of sheathless compared with sheathed transradial balloon guide access.

3D-Printed Disease Models for Neurosurgical Planning, Simulation, and Training

Spatial insight into intracranial pathology and structure is important for neurosurgeons to perform safe and successful surgeries. Three-dimensional (3D) printing technology in the medical field has made it possible to produce intuitive models that can help with spatial perception. Recent advances in 3D-printed disease models have removed barriers to entering the clinical field and medical market, such as precision and texture reality, speed of production, and cost. The 3D-printed disease model is now ready to be actively applied to daily clinical practice in neurosurgical planning, simulation, and training. In this review, the development of 3D-printed neurosurgical disease models and their application are summarized and discussed.

A prospective, first-in-human use of the NeVa mechanical thrombectomy device for patients with acute coronary syndromes

BACKGROUND

There is no established technique for managing large thrombus burden (LTB) in patients with acute coronary syndrome (ACS).

AIMS

The aim of this study was to assess the safety and efficacy of the NeVa (Vesalio) mechanical thrombectomy device (MTD) in ACS patients with LTB.

METHODS

Consecutive patients with ACS and LTB were treated with the NeVa MTD as the primary vessel recanalisation and thrombus removal modality, followed by conventional intervention. We further developed a bench model and applied to a subset of patients, a vacuum-assisted aspiration technique, exploiting 6 Fr-compatible conventional guiding catheter extensions, as an adjudicative manoeuvre to the use of stent-based MTD. A core laboratory reviewed the angiographic images for procedural complications, Thrombolysis In Myocardial Infarction (TIMI) flow, myocardial blush grade (MBG) and TIMI thrombus grade (TTG).

RESULTS

Between November 2019 and March 2021, 61 patients underwent thrombectomy with the NeVa device. Non-flow limiting and reversible coronary spasm occurred in 14 (23%) patients. One patient (#10) suffered from side branch embolisation, which was successfully treated with the NeVa, triggering the development of a vacuum-assisted aspiration technique in a bench model, which was then applied to the subsequent 51 patients. No other device-related complications occurred. After NeVa use, TIMI flow <3 decreased from 68.3% at baseline to 10.3% (p<0.001), MBG <2 from 65% to 27.6% (p<0.001), TTG ≥3 from 96.7% to 43.2% (p<0.001), respectively.

CONCLUSIONS

In patients with LTB, the NeVa MTD was safe and associated with high rates of vessel recanalisation and thrombus removal. The concomitant use of vacuum-assisted aspiration has potential to improve the effectiveness and safety of the technique.

Super large-bore ingestion of clot (SLIC) leads to high first pass effect in thrombectomy for large vessel occlusion

BACKGROUND

Super large-bore aspiration (SLBA) has shown high rates of complete clot ingestion.

OBJECTIVE

To report the initial clinical feasibility, safety, and efficacy of this novel SLBA insert combination-super large-bore ingestion of clot (SLIC) technique for stroke.

METHODS

We performed a retrospective review of three comprehensive stroke center databases. The SLIC technique entails a triaxial assembly of an 8 Fr 0.106″ Base Camp catheter, 0.088″ catheter extender (HiPoint), and an insert catheter (Tenzing 8) that completely consumes the inner diameter of the 0.088″ SLBA catheter. The HiPoint catheter is delivered over the Tenzing 8 to the face of the embolus, which is withdrawn, while aspirating through the Base Camp and HiPoint catheters as a single assembly.

RESULTS

Thirty-three consecutive patients with large vessel occlusion were treated with SLIC. The median age was 70 years (30-91) and 17 were male (51.5%). The median presenting National Institutes of Health Stroke Scale score and Alberta Stroke Program Early CT score was 21 (1-34) and 8 (5-10), respectively. There was 100% success in delivering the 0.088″ catheter to the site of the occlusion. The successful revascularization rate (modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2B) was 100% within a single pass in most cases (82%). Final mTICI ≥2C was achieved in 94.1% of occlusions, with 73.5% mTICI 3 recanalization. The rate of first pass effect in achieving excellent reperfusion (mTICI ≥2C) was 70.5%. There were no adverse events or postprocedural symptomatic hemorrhages.

CONCLUSIONS

Our initial experience with the SLIC technique resulted in achieving a first pass effect (mTICI ≥2C) in 70.5%. Navigation of the SLBA catheter extender over the Tenzing insert was successful and safe in this early experience.

A Review of the Advancements in the in-vitro Modelling of Acute Ischemic Stroke and Its Treatment

In-vitro neurovascular models of large vessel occlusions (LVOs) causing acute ischemic stroke (AIS) are used extensively for pre-clinical testing of new treatment devices. They enable physicians and engineers to examine device performance and the response of the occlusion to further advance design solutions for current unmet clinical needs. These models also enable physicians to train on basic skills, to try out new devices and new procedural approaches, and for the stroke team to practice workflows together in the comfort of a controlled environment in a non-clinical setting. Removal of the occlusive clot in its entirety is the primary goal of the endovascular treatment of LVOs via mechanical thrombectomy (MT) and the medical treatment via thrombolysis. In MT, recanalization after just one pass is associated with better clinical outcomes than procedures that take multiple passes to achieve the same level of recanalization, commonly known as first pass effect (FPE). To achieve this, physicians and engineers are continually investigating new devices and treatment approaches. To distinguish between treatment devices in the pre-clinical setting, test models must also be optimized and expanded become more nuanced and to represent challenging patient cohorts that could be improved through new technology or better techniques. The aim of this paper is to provide a perspective review of the recent advancements in the in-vitro modeling of stroke and to outline how these models need to advance further in future. This review provides an overview of the various in-vitro models used for the modeling of AIS and compares the advantages and limitations of each. In-vitro models remain an extremely useful tool in the evaluation and design of treatment devices, and great strides have been made to improve replication of physiological conditions. However, further advancement is still required to represent the expanding indications for thrombectomy and thrombolysis, and the generation of new thrombectomy devices, to ensure that smaller treatment effects are captured.

Per-pass analysis of recanalization and good neurological outcome in thrombectomy for stroke: Systematic review and meta-analysis

BACKGROUND AND AIM

First pass effect (FPE) is defined as achieving a complete recanalization with a single thrombectomy device pass. Although clinically desired, FPE is reached in less than 30% of thrombectomy procedures. Multiple device passes are often necessary to achieve successful or complete recanalization. We performed a systematic review and meta-analysis to determine the recanalization rate after each pass of mechanical thrombectomy and its association with good neurological outcome.

METHODS

A literature search was performed for studies reporting the number of device passes required for either successful (mTICI 2b or higher) or complete (mTICI 2c or higher) recanalization. Using random-effect meta-analysis, we evaluated the likelihood of recanalization and good neurological outcome (measured with the modified Rankin Score <2 at 90 days) after each device pass.

RESULTS

Thirteen studies comprising 4197 patients were included. Among cases with failed first pass, 24% of them achieved final complete recanalization and 45% of them achieved final successful recanalization. Independently to the total number of previously failed attempts, the likelihood of achieving successful recanalization was 30% per pass, and the likelihood to achieve complete recanalization was about 20% per pass. The likelihood of good neurological outcome in patients with final successful recanalization decreased after each device pass: 55% after the first pass, 48% after the second pass, 42% after the third pass, 36% after the fourth pass, and 26% for 5 passes or more.

CONCLUSION

Each pass is associated with a stable likelihood of recanalization but a decreased likelihood of good neurological outcome.

Flow control in the middle cerebral artery during thrombectomy: the effect of anatomy, catheter size and tip location

BACKGROUND

Catheter size, location and circle of Willis anatomy impact the flow conditions during interventional stroke therapy. The aim of the study was to systematically investigate the influence of these factors on flow control in the middle cerebral artery by means of a computational model based on 100 patients with stroke who received endovascular treatment.

METHODS

The dimensions of the cervical and intracranial cerebral arteries of 100 patients who received endovascular mechanical thrombectomy for acute ischemic stroke were measured and a three-dimensional model of the circle of Willis was created based on these data. Flow control in the middle cerebral artery with variations in catheter size, catheter location and configurations of collateral vessels was determined using a computational model. A total of 48 scenarios were analyzed.

RESULTS

Flow reversal with a distal aspiration catheter alone was not possible in the internal carotid artery and only sometimes possible in the middle cerebral artery (14 of 48 cases). The Catalyst 7 catheter was more often successful in achieving flow reversal than Catalyst 5 or 6 catheters (p<0.001). In a full circle of Willis anatomy, flow reversal was almost never possible. The absence of one or more communicating arteries significantly influenced flow direction compared with the full anatomy with all communicating arteries present (p=0.028).

CONCLUSION

Choosing the biggest possible aspiration catheter and locating it in the middle cerebral artery significantly increases the chances of successful flow control. Flow through the collaterals may impair the flow, and circle of Willis anatomy should be considered during aspiration thrombectomy.

Effect of first pass reperfusion on outcome in patients with posterior circulation ischemic stroke

BACKGROUND

First pass reperfusion (FPR), that is, excellent reperfusion (expanded treatment in cerebral ischemia (eTICI) 2C-3) in one pass, after endovascular treatment (EVT) of an occluded artery in the anterior circulation, is associated with favorable clinical outcome, even when compared with multiple pass excellent reperfusion (MPR). In patients with posterior circulation ischemic stroke (PCS), the same association is expected, but currently unknown. We aimed to assess characteristics associated with FPR and the influence of FPR versus MPR on outcomes in patients with PCS.

METHODS

We used data from the MR CLEAN Registry, a prospective observational study. The effect of FPR on 24-hour National Institutes of Health Stroke Scale (NIHSS) score, as percentage reduction, and on modified Rankin Scale (mRS) scores at 3 months, was tested with linear and ordinal logistic regression models.

RESULTS

Of 224 patients with PCS, 45 patients had FPR, 47 had MPR, and 90 had no excellent reperfusion (eTICI <2C). We did not find an association between any of the patient, imaging, or treatment characteristics and FPR. FPR was associated with better NIHSS (-45% (95% CI: -65% to -12%)) and better mRS scores (adjusted common odds ratio (acOR): 2.16 (95% CI: 1.23 to 3.79)) compared with no FPR. Outcomes after FPR were also more favorable compared with MPR, but the effect was smaller and not statistically significant (NIHSS: -14% (95% CI: -51% to 49%), mRS acOR: 1.50 (95% CI: 0.75 to 3.00)).

CONCLUSIONS

FPR in patients with PCS is associated with favorable clinical outcome in comparison with no FPR. In comparison with MPR, the effect of FPR was no longer statistically significant. Nevertheless, our data support the notion that FPR should be the treatment target to pursue in every patient treated with EVT.

Clot Meniscus Sign Is Associated With Thrombus Permeability and Choice of Mechanical Thrombectomy Technique in Acute Middle Cerebral Artery Occlusion

Background and Purpose

The method of mechanical thrombectomy (MT) is related to vascular anatomy and stroke etiology. Meniscus sign and thrombus permeability as imaging markers may be instructive for the selection of MT. This study aims to clarify the relationship among meniscus sign, thrombus permeability, and choice of MT in patients with acute middle cerebral artery occlusion.

Materials and Methods

A total of 111 patients with acute middle cerebral artery occlusion (MCAO) who underwent MT were retrospectively analyzed. Clot meniscus sign was defined as the appearance of meniscoid/edge-like or single- or double-wall contrast channels besides or around insular blood clots. The radiographic, clinical, and surgical data of patients with MCAO with or without meniscus sign were compared.

Results

The meniscus sign positive group (n = 26) has higher thrombus permeability (HUs) (26.92 ± 9.69 vs. 22.84 ± 7.88, p = 0.031) than those without it. Shorter puncture-to-recanalization (P2R) time (65.5 vs. 88, p = 0.012), higher complete recanalization rate (85.71 vs. 33.33%, p &lt; 0.01), and better clinical outcome (p &lt; 0.01) were obtained by selecting contact aspiration (CA) over stent retriever (SR) in patients with positive meniscus sign. In patients with negative meniscus sign, there was no significant difference in clinical outcome after receiving CA or SR.

Conclusion

Patients with MCAO with positive meniscus sign have higher thrombus permeability and are more suitable for CA to acquire better clinical outcomes.

Clot evaluation and distal embolization risk during mechanical thrombectomy in anterior circulation stroke

INTRODUCTION

Clot features along with patients' clinical features may influence thrombus compactness predisposing at distal embolization during thrombectomy. The aim of this study was to evaluate thrombus features assessed by radiological and histopathological analysis along with patient-related features to predict distal embolization during thrombectomy.

METHODS

We performed a retrospective analysis of a prospectively maintained dataset of a tertiary stroke center inclusive of all cases of endovascular treatment for acute ischemic stroke involving anterior circulation occlusion. All patients underwent head and neck CT-angiography (CTA) at baseline. Patients were enrolled if thrombus material was suitable for histopathologic analyses.

RESULTS

A total of 327 patients underwent mechanical thrombectomy between March 2017 and May 2020. Among them, 133 (40.7%) had thrombus material suitable for histopathological analysis but 11 patients were excluded due to posterior circulation occlusion. A total of 122 patients were included in the analysis. A distal embolism was documented in 27 patients (28.4%). Multivariable analysis with distal embolism as dependent variable showed an adjusted OR of 2.64 (95%CI: 0.9-7.73; p-value: 0.08) for anticoagulant therapy, an adjusted OR of 1.38 (95%CI: 1.01-1.91; p-value 0.05) each 5-mm increasing of thrombus length at CTA. No association was found with age, sex, thrombolysis and first thrombectomy technique used.

CONCLUSION

The combined effect of anticoagulant therapy and thrombus length may have a potentially harmful effect on reperfusion during mechanical recanalization, causing distal embolization and this aspect should be taken into account in patient's risk assessment and when planning treatment strategy.

Influence of single pass recanalization in acute ischemic stroke with large vessel occlusion in patients of Asian ethnicity

BACKGROUND AND PURPOSE

A previous report revealed single pass recanalization was associated with better functional outcome for patients with acute ischemic stroke with large vessel occlusion in real-world settings. However, the effect of single pass recanalization in acute large vessel occlusion based on the largest registry in real-world settings in Asian population are not well scrutinized.

MATERIALS AND METHODS

RESCUE-Japan Registry-2 was a physician-initiated prospective multicenter registry that enrolled consecutive patients with acute large vessel occlusion who were admitted within 24 h of onset. We compared patients who underwent endovascular therapy and achieved good recanalization in single or multiple device passes (single-pass group and multiple-passes group, respectively) in terms of the good outcome defined as modified Rankin Scale of 0-2 at 90 days after onset. We estimated the odds ratios, safety and mortality adjusting for confounders.

RESULTS

Among 2420 patients registered, 1281 patients treated with endovascular therapy. 829 patients were analyzed (557 patients in single-pass and 272 patients in multiple-passes group). Patient characteristics were almost similar between two groups. The good outcome was more observed of patients in the single groups (51.5% vs 39.3%). The adjusted odds ratio of single pass of good outcome was 1.92 (95% confidence interval, 1.37-2.69). The frequencies of symptomatic intracranial hemorrhage were similar between the two groups.

CONCLUSION

Single pass recanalization was associated with good clinical outcome on real-world settings in Asian population.

The Q and A-The MIVI Q Catheters for Aspiration Thrombectomy-Initial Experience from London

Background: Aspiration thrombectomy is a widely accepted treatment option for large vessel occlusion (LVO). The MIVI aspiration system has a novel design to maximize the lumen size. We present the results of our initial experience with this innovative aspiration thrombectomy system. Materials and Methods: Retrospectively, we reviewed our database to find all cases of LVO treated with the MIVI Q system (February 2019 and July 2020). In addition, we recorded the baseline demographics, NIHSS, ASPECT, mTICI scores, procedural time, complications, and 90 day mRS. Results: Herein, we identified 25 patients with an average age of 65.3 ± 19.3 years (range 19–89), majority of whom were female (n = 14, 56%). The average NIHSS was 16.9 ± 6.7 (range 6–30), and the average CT ASPECT was 7.9 ± 1.4 (range 5–10). The most common clot location was the M1 segment of the MCA (n = 16, 64%). Four of the patients had tandem lesions (16%). The average clot length was 21.7 ± 31 mm (range 2–130 mm). Of the 23 cases where the Q catheter reached the proximal clot face, mTICI ≥ 2b was achieved on the first pass in 11 cases (44%), and at the end of the ‘Q aspiration’ only the procedures with 16 patients achieved mTICI ≥ 2b recanalization (64%). Stent-retrievers were used in 13 cases (52%). At the end of the procedure, 24 patients (96%) achieved mTICI ≥ 2b with 18 patients (72%) achieving mTICI ≥ 2c. The average number of passes with the Q catheter, including when it was used for SOLUMBRA, was 2.1 ± 2.2 (range 1–10). The mean procedure time was 69 ± 32 mins (range 7–116 mins). No complications were associated with the MIVI Q. Conclusions: The MIVI aspiration system is a novel technology with regards to aspiration mechanical thrombectomy. The system is easy to use with early results comparable to other large-bore catheter systems. However, further studies are needed.