Comparing different thrombectomy techniques in five large-volume centers: a 'real world' observational study

Optimal Catheter Selection for Patients with Acute Stroke with Type III Aortic Arch Based on Magnetic Resonance Angiography Road Mapping of the Para-Aortic Transfemoral Access Route Before Mechanical Thrombectomy

BACKGROUND

Although mechanical thrombectomy for acute ischemic stroke has a high recanalization rate, procedurally challenging lesions remain in approximately 10% of the cases. Type III aortic arches, due to their anatomical configuration, are a fundamental problem impacting this procedure. This study aimed to determine whether optimal catheter selection for type III aortic arches, using magnetic resonance angiography (MRA)-based road mapping of the para-aortic transfemoral access route, reduces the time required for mechanical thrombectomy.

METHODS

We retrospectively evaluated 203 consecutive patients who underwent mechanical thrombectomy at multiple centers between April 2018 and July 2022. 23 patients were diagnosed with a type III aortic arch using MRA-based road mapping performed to visualize the para-aortic access route before neuro-interventional procedures. Among the 23 patients with type III aortic arches, 10 received a Simmons-type catheter (initial Simmons group) and 13 received a JB-2-type catheter (initial JB-2 group) as their first inner catheter. The time required for mechanical thrombectomy was compared between the groups.

RESULTS

Compared with the initial JB-2 group, the initial Simmons group exhibited a significantly shorter "puncture-to-recanalization time" (105 vs. 53 minutes, P = 0.009) and "door-to-recanalization time" (164 vs. 129 minutes, P = 0.032).

CONCLUSIONS

Optimal catheter selection by identifying the aortic arch before mechanical thrombectomy using MRA-based road mapping effectively reduced the mechanical thrombectomy time. This suggests that even in type III aorta cases, appropriate catheter selection may shorten the mechanical thrombectomy time and improve acute ischemic stroke prognosis.

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.

Placing the balloon-guide catheter in the high cervical segment of the internal carotid artery is associated with improved recanalization

BACKGROUND

Mechanical thrombectomy (MT) is part of the standard of care for stroke treatment, and improving its efficacy is one of the main objectives of clinical investigation. Of importance is placement of the distal end of balloon-guided catheters (BGC). We aim to determine if this influences outcomes.

METHODS

We analyzed data from the ASSIST Registry, an international, multicenter prospective study of 1492 patients. We divided patients treated with BGC according to the placement of the BGC: low cervical (LCG (the lower 2/3 of cervical internal carotid artery (ICA)) or high cervical (HCG (upper 1/3 of cervical ICA, petro-lacerum or higher)). We analyzed characteristics and outcomes overall and stratified on the primary MT technique: Stent-Retriever only (SR Classic), Combined use of aspiration catheter and SR (Combined), and Direct Aspiration (ADAPT).

RESULTS

Our study included 704 subjects -323 in the low cervical and 381 in the high cervical groups. Statistical differences were seen in the proportion of females and tandem lesions (both higher for LCG). Placing the BGC in the high cervical segment is associated with better recanalization rates (expanded treatment in cerebral infarction (eTICI) score of 2c-3) at the end of the procedure (P<0.0001) and shorter procedures (P=0.0005). After stratifying on the three primary techniques (SR Classic, Combined, and ADAPT), placing the BGC in the high segment is associated with a better first-pass effect (FPE), less distal emboli, and better clinical outcomes in the SR Classic technique.

CONCLUSIONS

Placing the distal end of the BGC at the high cervical segment or higher is associated with better recanalization.

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.

Efficacy and safety of combined stent retriever and contact aspiration vs. stent retriever alone on revascularization in patients with acute ischemic stroke: a systematic review and meta-analysis

Objective

Whether the efficacy of combined stent retriever and contact aspiration (S + A) is superior to stent retriever (S) alone for revascularisation in patients with large vessel occlusive stroke remains uncertain. The aim of this meta-analysis was to assess the safety and efficacy of combined stent retriever and contact aspiration for the treatment of acute ischaemic stroke with large vessel occlusion by comparing it with stent retriever alone.

Methods

We systematically searched the PubMed, Embase, Web of Science, and The Cochrane Library databases for randomised controlled trials and observational studies (case-control and cohort studies) published before 1 October 2023 comparing the efficacy of combined stent retriever and contact aspiration versus tent retriever alone in patients with large vessel occlusive stroke. The end point of the primary efficacy observed in this meta-analysis study was the rate of first pass nearly complete or complete recanalisation (mTICI 2c-3). Secondary effectiveness nodes were: rate of first pass successful recanalisation (mTICI 2b-3), rate of near-complete or complete recanalisation of the postoperative vessel, rate of successful recanalisation of the postoperative vessel, and MRS 0-2 within 90 days. Safety endpoints were interoperative embolism, symptomatic intracranial haemorrhage, and mortality within 90 days.

Results

A total of 16 studies were included in the literature for this meta-analysis, with a total of 7,320 patients (S + C group: 3,406, S group: 3,914). A comprehensive analysis of the included literature showed that combined stent retriever and contact aspiration had a higher rate of near-complete or complete recanalisation of the postoperative vessel [OR = 1.53, 95% CI (1.24, 1.88), p < 0.0001] and rate of successful recanalisation of the postoperative vessel compared to stent retriever alone [OR = 1.83, 95% CI (1.55, 2.17), p < 0.00001]; there were no statistically significant differences between the two groups in terms of the rate of first pass nearly complete or complete recanalisation [OR = 1.00, 95% CI (0.83, 1.19), p = 0.96], rate of first pass successful recanalisation [OR = 1.02, 95% CI (0.85, 1.24), p = 0.81], interoperative embolism [OR = 0.93, 95% CI (0.72, 1.20), p = 0.56], symptomatic intracranial haemorrhage [OR = 1.14, 95% CI (0.87, 1.48), p = 0.33], MRS 0-2 within 90 days [OR = 0.89, 95% CI (0.76, 1.04), p = 0.14] and mortality within 90 days [OR = 1.11, 95% CI (0.94, 1.31), p = 0.22].

Conclusion

Combined stent retriever and contact aspiration has a higher rate of postprocedural revascularisation (mTICI 2c-3/mTICI 2b-3) compared with stent retriever alone in patients with large vessel occlusion stroke. In addition, it was not superior to stenting alone in terms of the rate of first pass recanalisation (mTICI 2c-3/mTICI 2b-3), interoperative embolisation, symptomatic intracranial haemorrhage, good functional prognosis within 90 days and mortality within 90 days.

Efficacy and safety of SOFIA aspiration catheter for mechanical thrombectomy via ADAPT and Solumbra echniques in acute ischemic stroke: A systematic review and meta-analysis

INTRODUCTION

SOFIA catheter is a relatively new and recently FDA-approved aspiration catheter. This systematic review aims to investigate the safety and efficacy of SOFIA catheter for treatment of acute ischemic stroke (AIS) via ADAPT and Solumbra techniques.

METHODS

Search of all studies evaluating the SOFIA catheter for mechanical thrombectomy (MT) for treatment of AIS via ADAPT and Solumbra techniques from inception through 2020 on Pubmed, PMC, and Embase was performed. We analyzed the angiographic and clinical outcomes of both techniques with SOFIA catheter using the random-effects model.

RESULTS

From 18 studies, 1836 patients were included with 1365 receiving MT using ADAPT and 471 with solumbra technique. The mean age was 69.8 years and 51.1% of the patients were women. The rate of rescue therapy was 30%. The outcomes rates of ADAPT group were as follows; mFPE (59.3%), FPE (34.4%) final TICI 2b/3 (89.3%), procedural complications (8%), embolization to new territory (ENT) (2.3%), symptomatic ICH (5.4%), mean NIHSS (8.97), 90-day-mRS 0-2 (48.8%), and mortality (15.3%). The outcomes rates of Solumbra group were as follows; mFPE (60.5%), FPE (46.7%), final TICI 2b/3 (93%), procedural complications (6.4%), ENT (2%), symptomatic ICH (6%), mean NIHSS (7.59), mRS 0-2 (53.8%), and mortality (10.8%). ICA and posterior circulation strokes, and tandem lesions had worse outcomes (P < .005). MCA strokes were associated with better outcomes (P = .005). ASPECT scores' association with the clinical outcomes was found statistically significant.

CONCLUSION

SOFIA catheter is effective and safe to treat acute ischemic stroke regardless of applied MT technique.

Comparison of 4 mm-sized and 3 mm-sized Stent Retrievers in Mechanical Thrombectomy for M2 Occlusion

INTRODUCTION

A stent retriever (SR) is widely used in mechanical thrombectomy (MT) for M2 segment occlusion. However, the suitable size of SR in M2 occlusion remains unclear. Therefore, we aimed to compare 4 mm-sized SR with 3 mm-sized SR in M2 occlusion.

METHODS

Patients who underwent MT with SR for M2 occlusion were dichotomized into 4×20 mm SR and 3×20 mm SR groups. Then, 1:1 propensity score matching was performed. The M2 segment was divided into proximal and distal segments according to the occlusion site. Subgroup analysis was then performed for each cohort.

RESULTS

A total of 111 patients were enrolled, with 4×20 mm SR and 3×20 mm SR applied in 72 (64.9%) and 39 (35.1%) cases, respectively. In propensity score matching, mean number of stent passages for reperfusion was significantly lower in the 4×20 mm SR group than in the 3×20 mm SR group (1.5 ± 0.8 vs. 2.1 ± 1.1; p = 0.004). First-pass reperfusion (FPR) was more highly achieved in the 4×20 mm SR group than in the 3×20 mm SR group (52.6% vs. 42.1%; p = 0.007). In both proximal and distal occlusion cohorts, the 4 mm SR group showed lower mean number of SR passage (p = 0.004 and p = 0.003, respectively) and higher FPR rate than the 3 mm SR group (p = 0.003 and p = 0.007, respectively).

CONCLUSION

In MT for M2 occlusion, 4×20 mm SR enables an effective procedure with lesser SR passage for reperfusion and a higher rate of FPR than 3×20 mm SR.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Intracranial Carotid Occlusions : ADAPT versus SAVE and the role of Balloon Guide Catheters

PURPOSE

Specific decisions made by neurointerventionists are often lost behind the data of large-scale trials, and many of these studies have taken place before the development of new techniques and devices. This study compares the stent-retriever assisted vacuum-locked extraction (SAVE) technique with a direct aspiration first pass (ADAPT), as well as the use of a balloon guide catheter (BGC), in intracranial internal carotid artery (IC-ICA) occlusions.

METHODS

Observational and retrospective study from an Italian hospital, including patients who underwent thrombectomy for IC-ICA occlusion between 1 January 2019 and 31 March 2021.

RESULTS

Out of 91 IC-ICA occlusions, the ADAPT was the first choice in 20 (22%) and the SAVE in 71 (78%). A BGC was used in 32 (35%) cases, always in conjunction with the SAVE technique. The use of SAVE technique without BGC was associated with the least risk of distal embolization (DE) in the territory occluded (44% vs. 75% when ADAPT technique was used; p = 0.03) and achieved first pass effect (FPE) more frequently (51% vs. 25%, p = 0.09). When the SAVE technique was used, BGC (BGC-SAVE) compared to no BGC (NoBGC-SAVE) was associated with a tendency for less DE (31% vs. 44%, p = 0.3), more FPE (63% vs. 51%, p = 0.5), the same median number of passes (1, p = 0.8) and similar groin-to-recanalization times (36.5 vs. 35.5 min, p = 0.5), none of which reached statistical significance.

CONCLUSION

Our findings support the use of SAVE technique for IC-ICA occlusions; the added benefit of BGC compared to long sheaths was not remarkable in this sample.

Mechanical thrombectomy with combined stent retriever and contact aspiration versus stent retriever alone for acute large vessel occlusion: data from ANGEL-ACT registry

BACKGROUND AND PURPOSE

An analysis of the ASTER 2 trial revealed similar final recanalisation levels and clinical outcomes in acute large vessel occlusion (LVO) stroke between stent retrieval (SR) alone as a first-line mechanical thrombectomy (MT) technique (SR alone first-line) and concomitant use of contact aspiration (CA) plus SR as a first-line MT technique (SR+CA first-line). The purpose of the present study was to compare the safety and efficacy of SR+CA first-line with those of SR alone first-line for patients with LVO in China.

METHODS

We conducted the present study by using the data from the ANGEL-ACT registry. We divided the selected patients into SR+CA first-line and SR alone first-line groups. We performed logistic regression and generalised linear models with adjustments to compare the angiographic and clinical outcomes, including successful/complete recanalisation after the first technique alone and all procedures, first-pass successful/complete recanalisation, number of passes, 90-day modified Rankin Scale, procedure duration, rescue treatment and intracranial haemorrhage within 24 hours.

RESULTS

Of the 1233 enrolled patients, 1069 (86.7%) received SR alone first-line, and 164 (13.3%) received SR+CA first-line. SR+CA first-line was associated with more thrombectomy passes (3 (2-4) vs 2 (1-2); β=1.77, 95% CI=1.55 to 1.99, p<0.001), and longer procedure duration (86 (60-129) min vs 80 (50-122) min; β=10.76, 95% CI=1.08 to 20.43, p=0.029) than SR alone first-line group. Other outcomes were comparable (all p>0.05) between the two groups.

CONCLUSIONS

Patients undergoing SR+CA first-line had more thrombectomy passes and longer procedure duration than patients undergoing SR alone first-line. Additionally, we suggested that SR+CA first-line was not superior to SR alone first-line in final recanalisation level, first-pass recanalisation level and 90-day clinical outcomes in the Chinese population.

Different types of percutaneous endovascular interventions for acute ischemic stroke

BACKGROUND

Acute ischemic stroke (AIS) is the abrupt reduction of blood flow to a certain area of the brain which causes neurologic dysfunction. Different types of percutaneous arterial endovascular interventions have been developed, but as yet there is no consensus on the optimal therapy for people with AIS.

OBJECTIVES

To compare the safety and efficacy of different types of percutaneous arterial endovascular interventions for treating people with AIS.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4 of 12, 2022), MEDLINE Ovid (1946 to 13 May 2022), Embase (1947 to 15 May 2022), Science Citation Index Web of Science (1900 to 15 May 2022), Scopus (1960 to 15 May 2022), and China Biological Medicine Database (CBM; 1978 to 16 May 2022). We also searched the ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 16 May 2022.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing one percutaneous arterial endovascular intervention with another in treating adult patients who have a clinical diagnosis of AIS due to large vessel occlusion and confirmed by imaging evidence, including thrombo-aspiration, stent-retrieval thrombectomy, aspiration-retriever combined technique, and thrombus mechanical fragmentation.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the literature searches, identified eligible trials, and extracted data. A third review author participated in discussions to reach consensus decisions when any disputes occurred. We assessed risk of bias and applied the GRADE approach to evaluate the quality of the evidence. The primary outcome was rate of modified Rankin Scale (mRS) of 0 to 2 at three months. Secondary outcomes included the rate of modified Thrombolysis In Cerebral Infarction (mTICI) of 2b to 3 postprocedure, all-cause mortality within three months, rate of intracranial hemorrhage on imaging at 24 hours, rate of symptomatic intracranial hemorrhage at 24 hours, and rate of procedure-related adverse events within three months.

MAIN RESULTS

Four RCTs were eligible. The current meta-analysis included two trials with 651 participants comparing thrombo-aspiration with stent-retrieval thrombectomy. We judged the quality of evidence to be high in both trials according to Cochrane's risk of bias tool RoB 2. There were no significant differences between thrombo-aspiration and stent-retrieval thrombectomy in rate of mRS of 0 to 2 at three months (risk ratio [RR] 0.97, 95% confidence interval [CI] 0.82 to 1.13; P = 0.68; 633 participants; 2 RCTs); rate of mTICI of 2b to 3 postprocedure (RR 1.01, 95% CI 0.95 to 1.07; P = 0.77; 650 participants; 2 RCTs); all-cause mortality within three months (RR 1.01, 95% CI 0.74 to 1.37; P = 0.95; 633 participants; 2 RCTs); rate of intracranial hemorrhage on imaging at 24 hours (RR 1.03, 95% CI 0.86 to 1.24; P = 0.73; 645 participants; 2 RCTs); rate of symptomatic intracranial hemorrhage at 24 hours (RR 0.90, 95% CI 0.49 to 1.68; P = 0.75; 645 participants; 2 RCTs); and rate of procedure-related adverse events within three months (RR 0.98, 95% CI 0.68 to 1.41; P = 0.90; 651 participants; 2 RCTs). Another two included studies reported no differences for the comparisons of combined therapy versus stent-retrieval thrombectomy or thrombo-aspiration. One RCT is ongoing.

AUTHORS' CONCLUSIONS

This review did not establish any difference in safety and effectiveness between the thrombo-aspiration approach and stent-retrieval thrombectomy for treating people with AIS. Furthermore, the combined group did not show any obvious advantage over either intervention applied alone.

MASTRO I: Meta-Analysis and Systematic Review of thrombectomy stent retriever outcomes: comparing functional, safety and recanalization outcomes between EmboTrap, Solitaire and Trevo in acute ischemic stroke

Aim: Stent-retriever (SR) thrombectomy has demonstrated superior outcomes in patients with acute ischemic stroke compared with medical management alone, but differences among SRs remain unexplored. We conducted a Systematic Review/Meta-Analysis to compare outcomes between three SRs: EmboTrap®, Solitaire™, and Trevo®. Methods: We conducted a PRISMA-compliant Systematic Review among English-language studies published after 2014 in PubMed/MEDLINE that reported SRs in ≥25 patients. Functional and safety outcomes included 90-day modified Rankin scale (mRS 0-2), mortality, symptomatic intracranial hemorrhage (sICH), and embolization to new territory (ENT). Recanalization outcomes included modified thrombolysis in cerebral infarction (mTICI) and first-pass recanalization (FPR). We used a random effects Meta-Analysis to compare outcomes; subgroup and outlier-influencer analysis were performed to explore heterogeneity. Results: Fifty-one articles comprising 9,804 patients were included. EmboTrap had statistically significantly higher rates of mRS 0-2 (57.4%) compared with Trevo (50.0%, p = 0.013) and Solitaire (45.3%, p < 0.001). Compared with Solitaire (20.4%), EmboTrap (11.2%, p < 0.001) and Trevo (14.5%, p = 0.018) had statistically significantly lower mortality. Compared with Solitaire (7.7%), EmboTrap (3.9%, p = 0.028) and Trevo (4.6%, p = 0.049) had statistically significantly lower rates of sICH. There were no significant differences in ENT rates across all three devices (6.0% for EmboTrap, 5.3% for Trevo, and 7.7% for Solitaire, p = 0.518). EmboTrap had numerically higher rates of recanalization; however, no statistically significant differences were found. Conclusion: The results of our Systematic Review/Meta-Analysis suggest that EmboTrap may be associated with significantly improved functional outcomes compared with Solitaire and Trevo. EmboTrap and Trevo may be associated with significantly lower rates of sICH and mortality compared with Solitaire. No significant differences in recanalization and ENT rates were found. These conclusions are tempered by limitations of the analysis including variations in thrombectomy techniques in the field, highlighting the need for multi-arm RCT studies comparing different SR devices to confirm our findings.

Operator assessment versus core laboratory adjudication of recanalization following endovascular treatment of acute ischemic stroke: a systematic review and meta-analysis

BACKGROUND

Successful recanalization after endovascular thrombectomy serves as the primary endpoint in clinical trials and is a crucial predictor of long-term outcomes. Radiographic outcomes for various interventions have been shown to vary based on the type of interpreter, including the site interventionalist compared with an independent reader.

OBJECTIVE

To compare angiographic outcomes in stroke thrombectomy procedures based on the type of reader.

METHODS

A systematic literature search was conducted in Medline, EMBASE, Scopus, and Web-of-Science through February 2022. We included primary studies that reported core laboratory-read and operator angiographic outcomes after mechanical thrombectomy for ischemic stroke. Furthermore, study-defined successful recanalization data were collected.

RESULTS

Eight studies were included with 4797 patients, 51.2% of whom were male. Four thousand, four hundred and thirty-one patients had core readings, and 4211 had operator readings. Study-defined successful recanalization was significantly higher for operator (84%, 3543/4211) examinations than for core laboratory-read (78.4%, 3476/4431) examinations (p<0.001; OR=1.462, 95% CI 1.175 to 1.819). The modified Thrombolysis in Cerebral Infarction (mTICI) scale score of ≥2 b was higher for operator (85%, 3341/3929) examinations than for core laboratory-read (78.6%, 3107/3952) examinations (p<0.001; OR=1.349, 95% CI 1.071 to 1.701). mTICI 3 was significantly higher for operator (54.6%, 1000/1832) examinations than for core laboratory-read (39.9%, 731/1832) examinations (p<0.001; OR=1.823, 95% CI 1.598 to 2.081).

CONCLUSION

Operator angiographic reads are statistically significantly higher than core laboratory-read readings following stroke thrombectomy, especially for complete recanalization. These differences should be considered when interpreting reports of angiographic outcomes after thrombectomy.

Frontline thrombectomy strategy and outcome in acute basilar artery occlusion

BACKGROUND

Novel thrombectomy strategies emanate expeditiously day-by-day counting on access system, clot retriever device, proximity to and integration with the thrombus, and microcatheter disengagement. Nonetheless, the relationship between native thrombectomy strategies and revascularization success remains to be evaluated in basilar artery occlusion (BAO).

PURPOSE

To compare the safety and efficacy profile of key frontline thrombectomy strategies in BAO.

METHODS

Retrospective analyses of prospectively maintained stroke registries at two comprehensive stroke centers were performed between January 2015 and December 2019. Patients with BAO selected after MR imaging were categorized into three groups based on the frontline thrombectomy strategy (contact aspiration (CA), stent retriever (SR), or combined (SR+CA)). Patients who experienced failure of clot retrieval followed by an interchanging strategy were categorized as a fourth (switch) group. Clinicoradiological features and procedural variables were compared. The primary outcome measure was the rate of complete revascularization (modified Thrombolysis in Cerebral Infarction (mTICI) grade 2c-3). Favorable outcome was defined as a 90 day modified Rankin Scale score of 0-2.

RESULTS

Of 1823 patients, we included 128 (33 underwent CA, 35 SR, 35 SR +CA, and 25 switch techniques). Complete revascularization was achieved in 83/140 (59%) primarily analyzed patients. SR +CA was associated with higher odds of complete revascularization (adjusted OR 3.04, 95% CI 1.077 to 8.593, p=0.04) which was an independent predictor of favorable outcome (adjusted OR 2.73. 95% CI 1.152 to 6.458, p=0.02). No significant differences were observed for symptomatic intracranial hemorrhage, functional outcome, or mortality rate.

CONCLUSION

Among BAO patients, the combined technique effectively contributed to complete revascularization that showed a 90 day favorable outcome with an equivalent complication rate after thrombectomy.

Efficacy of Balloon Guide Catheter-Assisted Thrombus Repair in Stroke Treatment: A Retrospective Survey in China

Background

The first-pass (FP) effect, defined by successful cerebral reperfusion from a single pass of an endovascular stentriever, was associated with shorter procedural times and possible improved outcomes in patients with ischemic stroke secondary to large vessel occlusion. The adjunctive use of balloon guide catheter (BGC) may increase the rates of the first-pass effect. In this retrospective study we examined the impact of BGC on the first-pass effect in acute stroke patients.

Methods

We included patients with acute ischemic stroke with large vessel occlusion treated by endovascular thrombectomy from 2018 to 2019. We categorized the cases into BGC and non-BGC groups. Differences in time metrics and outcomes were compared.

Result

One hundred and thirty-two patients were included, and sixty-two were in BGC group (47.0%). The median procedural time was shorter (83.0 minutes vs 120.0 minutes, P = 0.000), and FP rate was higher in BGC group (58.1% vs 32.9%, P = 0.004) compared with non-BGC group. Proportion of modified Thrombolysis in Cerebral Infarction (mMTICI) 3 was higher (66.1% vs 37.1%, P = 0.001), and modified Rankin Scale (mRS) 0 to 2 was higher (59.7% vs 41.4%, P = 0.036) in BGC group compared with non-BGC group. In addition, BGC was associated with successful reperfusion odds ratio, 0.383; 95% confidence interval: 0.174-0.847; P = 0.018). The FP rate of BGC in the distal ICA was higher than that in the proximal ICA (87.5% vs 39.5%, P = 0.000), and the good clinical outcome rate at 90 days in the distal ICA was also higher than that in the proximal ICA (91.7% vs 39.5%, P = 0.000).

Conclusion

We showed that BGC shortened the procedural time and increased the rate of the successful FP. We recommend that BGC could be considered the preferred technique for endovascular intervention in stroke.

Mechanical thrombectomy for acute ischemic stroke in COVID-19 patients: multicenter experience in 111 cases

BACKGROUND

Data on the frequency and outcome of mechanical thrombectomy (MT) for large vessel occlusion (LVO) in patients with COVID-19 is limited. Addressing this subject, we report our multicenter experience.

METHODS

A retrospective cohort study was performed of consecutive acute stroke patients with COVID-19 infection treated with MT at 26 tertiary care centers between January 2020 and November 2021. Baseline demographics, angiographic outcome and clinical outcome evaluated by the modified Rankin Scale (mRS) at discharge and 90 days were noted.

RESULTS

We identified 111 out of 11 365 (1%) patients with acute or subsided COVID-19 infection who underwent MT due to LVO. Cardioembolic events were the most common etiology for LVO (38.7%). Median baseline National Institutes of Health Stroke Scale score and Alberta Stroke Program Early CT Score were 16 (IQR 11.5-20) and 9 (IQR 7-10), respectively. Successful reperfusion (mTICI ≥2b) was achieved in 97/111 (87.4%) patients and 46/111 (41.4%) patients were reperfused completely. The procedure-related complication rate was 12.6% (14/111). Functional independence was achieved in 20/108 (18.5%) patients at discharge and 14/66 (21.2%) at 90 days follow-up. The in-hospital mortality rate was 30.6% (33/108). In the subgroup analysis, patients with severe acute COVID-19 infection requiring intubation had a mortality rate twice as high as patients with mild or moderate acute COVID-19 infection. Acute respiratory failure requiring ventilation and time interval from symptom onset to groin puncture were independent predictors for an unfavorable outcome in a logistic regression analysis.

CONCLUSION

Our study showed a poor clinical outcome and high mortality, especially in patients with severe acute COVID-19 infection undergoing MT due to LVO.

Predictors of first-pass reperfusion for mechanical thrombectomy in acute ischemic stroke

BACKGROUND AND OBJECTIVE

Rapid reperfusion of ischemic penumbra in patients with acute stroke is critical to neurological recovery. Achieving reperfusion after first-pass mechanical thrombectomy has been associated with improved patient outcomes. However, the predictors for obtaining first-pass reperfusion are not well known.

METHODS

A single-institution retrospective study of all patients who underwent mechanical thrombectomy at a tertiary care center from January 2010 until March 2019 was conducted to assess for predictors of first-pass reperfusion.

RESULTS

A total of 257 patients were reviewed. Successful reperfusion was obtained in 63.4% of patients, and in 38% of patients on the first pass. On multivariate analysis, increasing door-to-puncture time was a negative predictor of FPR (OR 0.989, 95% CI = 0.980-0.997) and use of combined thrombectomy technique with stent-retriever and aspiration was a positive predictor of FPR compared to aspiration or stent-retriever alone (OR 4.441, 95% CI = 1.001-19.699).

CONCLUSIONS

Combination therapy using stent-retriever and aspiration may increase the chance of obtaining FPR, whereas delays in starting the procedure after patient arrival may decrease the odds of FPR. Rapid thrombectomy initiation and procedural technique may play in optimizing rates of FPR and ultimately patient outcomes, however, randomized controlled trials assessing these variables are necessary to determine optimal treatment strategies.

A Meta-analysis of Combined Aspiration Catheter and Stent Retriever versus Stent Retriever Alone for Large-Vessel Occlusion Ischemic Stroke

BACKGROUND

The efficacy of combined aspiration catheter and stent retriever compared with stent retriever alone for the treatment of large-vessel occlusion acute ischemic stroke is unclear.

PURPOSE

Our aim was to conduct a systematic literature review and meta-analysis on several metrics of efficacy comparing aspiration catheter and stent retriever with stent retriever alone.

DATA SOURCES

MEDLINE and the Cochrane Library Databases were searched. Randomized controlled trials and case-control and cohort studies were included.

STUDY SELECTION

Ten comparative studies were included detailing a combined 1495 patients with aspiration catheter and stent retriever and 1864 with stent retrievers alone.

DATA ANALYSIS

Data on first pass effect (TICI 2b/2c/3 after first pass), final successful reperfusion (modified TICI ≥2b), and 90-day functional independence (mRS ≤ 2) were collected. Meta-analysis was performed using a random-effects model.

DATA SYNTHESIS

There was a pooled composite first pass effect of 40.8% (611/1495) versus 32.6% (608/1864) for aspiration catheter and stent retriever and stent retriever alone, respectively (P < .0001). Similarly, on a meta-analysis, aspiration catheter and stent retriever were associated with a higher first pass effect compared with stent retriever alone (OR = 1.63; 95% CI, 1.20-2.21; P = .002; I² = 72%). There was no significant difference in composite rates of successful reperfusion between aspiration catheter and stent retriever (72.8%, 867/1190) and stent retriever alone (70.8%, 931/1314) (P = .27) or on meta-analysis (OR = 1.31; CI, 0.81-2.12; P = .27; I² = 82%). No difference was found between aspiration catheter and stent retriever and stent retriever alone on 90-day functional independence (OR = 1.02; 95% CI, 0.77-1.36; P = .88; I² = 40%).

LIMITATIONS

This study is limited by high interstudy heterogeneity.

CONCLUSIONS

On meta-analysis, aspiration catheter and stent retriever are associated with a superior first pass effect compared with stent retriever alone, but they are not associated with statistically different final reperfusion or functional independence.

Repeated-Manual Aspiration with Maximum Pressure (r-MAX): A New Technique of Mechanical Thrombectomy Using Syringe Aspiration

Objective

We report a new contact aspiration technique using syringe aspiration called repeated-manual aspiration with maximum pressure (r-MAX).

Case Presentation

From January 2020 to May 2021, 18 patients underwent mechanical thrombectomy with r-MAX for occlusion of the internal carotid artery, the first division of the middle cerebral artery (M1), and basilar artery occlusion. In this method, the aspiration catheter is first guided to the occlusion site, and then, two VacLok syringes are connected to the aspiration catheter. Next, the three-way stopcock is released in one direction. After 15 seconds, the direction of the three-way stopcock is switched. In the meantime, negative pressure is reapplied through the syringe, and the direction of the three-way stopcock is switched again. After reapplying negative pressure through the syringe and switching the three-way stopcock two more times, the aspiration catheter is removed. First-pass thrombolysis in cerebral infarction (TICI) scale 3 recanalization was achieved in 11 out of 18 patients (61.1%). In all, 11 patients (61.1%) achieved modified Rankin Scale scores of 0-2 at 90 days. Asymptomatic hemorrhage was observed in two patients (11.1%), and no patients had symptomatic hemorrhage.

Conclusion

The r-MAX technique using syringe aspiration can be employed as one of the methods of contact aspiration.

Should the direct aspiration first pass technique be advocated over the stent-retriever technique for acute ischemic stroke? A systematic review and meta-analysis of 7692 patients

Background:

The present meta-analysis aimed to synthesize evidence from all published studies with head-to-head data on the outcomes of a direct aspiration first pass technique (ADAPT) and the stent-retriever (SR) in acute ischemic stroke (AIS) patients.

Methods:

We searched PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials from inception to March 2021 for relevant clinical trials and observational studies. Eligible studies were identified, and all relevant outcomes were pooled in the meta-analysis random-effects model of DerSimonian-Laird.

Results:

Thirty studies were included in the meta-analysis with a total of 7868 patients. Compared with the SR, the ADAPT provides slightly higher rates of successful recanalization (RR 1.06, 95% CI [1.02 to 1.10]) and complete recanalization (RR 1.20, 95% CI [1.01 to 1.43]) but with more need for rescue therapy (RR 1.81, 95% CI [1.29 to 2.54]). There were no significant differences between the two techniques in terms of mortality at discharge, mortality at 90 days, change in the National Institutes of Health Stroke Scale score, the favorable outcome (modified Rankin scale (mRS) of 0-2), time to the groin puncture, or frequency of complications as intracerebral hemorrhage (ICH), symptomatic intracranial hemorrhage (sICH), embolus in a new territory (ENT), hemorrhagic infarction, parenchymal hematoma, subarachnoid hemorrhage, or procedural complications (all P > 0.05).

Conclusion:

Current evidence supports the use of the ADAPT technique to achieve successful and complete recanalization while considering the higher need for rescue therapy in some patients.

Aspiration-Retriever Technique for Stroke with Large Bore Intermediate Catheter : A Single Center Experience

Objective

Early successful reperfusion is associated with favorable outcomes in acute ischemic stroke (AIS). The purpose of this study was to achieve successful recanalization by a combined mechanical thrombectomy technique, the Aspiration-Retriever Technique for Stroke (ARTS), which is composed of a flexible large lumen distal access catheter and a retrievable stent as the first-line strategy of mechanical thrombectomy.

Methods

We retrospectively reviewed 62 patients with AIS who underwent mechanical thrombectomy from 2018 to 2019 at our institute by a senior neurointerventionalist. Among them, patients who were treated using the ARTS technique with the soft torqueable catheter optimized for intracranial access (SOFIA^®; MicroVention-Terumo, Tustin, CA, USA) as the first-line treatment were included. Patients who had tandem occlusions or underlying intracranial artery stenosis were excluded. The angiographic and clinical outcomes were evaluated. The angiographic outcome was analyzed by the rate of successful recanalization, defined as a Thrombolysis in Cerebral Infarction score of 2b or 3 at the end of all procedures and the rate of successfully achieving the first pass effect (FPE), defined as complete recanalization with a single pass of the device. The clinical outcomes included the National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin Scale (mRS), and mortality.

Results

A total of 27 patients (mean age, 59.3 years) fulfilled the inclusion criteria. The successful recanalization rate was 96% (n=26) while the FPE rate was 41% (n=11). The mean post-procedural NIHSS change was -3.0. Thirteen patients (48%) showed good clinical outcomes after thrombectomy with the ARTS technique (mRS at 90 days ≤2). Postoperative complications occurred in seven of 25 patients : hemorrhagic transformation in six patients (22%) and distal embolization in one patient (4%). Mortality was 15% (n=4).

Conclusion

Although the clinical outcomes using the ARTS technique with a flexible large lumen distal access catheter performed as the frontline thrombectomy in patients with AIS were not significantly superior than those of other studies, this study showed a high rate of successful endovascular recanalization which was comparable to that of other studies. Therefore, ARTS using the SOFIA^® catheter can be considered as the first choice of treatment for AIS due to large vessel occlusion.

Combined Approach to Stroke Thrombectomy Using a Novel Short Flexible Aspiration Catheter with a Stent Retriever : Preliminary Clinical Experience

BACKGROUND

Large-bore aspiration catheters enabling greater flow rates and suction force for mechanical thrombectomy might improve outcomes in patients with stroke secondary to large-vessel occlusion. Complete or near-complete reperfusion after a single thrombectomy pass (first-pass effect) is associated with improved clinical outcomes. We assessed the efficacy and safety of novel MIVI Q™ aspiration catheters in combination with stent-retriever devices.

METHODS

We retrospectively analyzed demographics, procedure characteristics, and clinical data from consecutive patients with acute anterior large-vessel occlusion treated with a combined approach using MIVI Q™ aspiration catheters and stent retrievers. Reperfusion was defined according to the modified thrombolysis in cerebral infarction (mTICI) score. Clinical outcomes were measured by the National Institute of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) scores.

RESULTS

We included 52 patients (median age, 75 y IQR: 64-83); 31 (59.6%) women; 14 (26.9%) with terminal internal carotid artery occlusions, 26 (50%) middle cerebral artery (MCA) segment M1 occlusions, and 12 (23.1%) MCA segment M2 occlusions; median NIHSS score at admission was 19 (IQR: 13-22). After the first pass, 25 (48%) patients had mTICI ≥ 2c. At the end of the procedure, 47 (90.4%) had mTICI ≥ 2b and 35 (67.3%) had mTICI ≥ 2c. No serious device-related adverse events were observed. Symptomatic intracranial hemorrhage developed in 1 patient. Mean NIHSS score was 13 at 24 h and 5 at discharge. At 90 days, 24 (46.2%) patients were functionally independent (mRS 0-2).

CONCLUSION

This preliminary study found good efficacy and safety for MIVI Q™ aspiration catheters used in combination with stent-retriever devices.

Blind Exchange With Mini-Pinning Technique Using the Tron Stent Retriever for Middle Cerebral Artery M2 Occlusion Thrombectomy in Acute Ischemic Stroke

Introduction: The usefulness of the blind exchange with mini-pinning (BEMP) technique has recently been reported for mechanical thrombectomy in patients with stroke owing to medium vessel occlusion (MeVO). The Tron stent retriever can be delivered and deployed through a 0.0165-inch microcatheter. This retriever has potential as an effective and safe treatment for acute ischemic stroke (AIS) due to occlusion of the M2 segment of the middle cerebral artery (MCA). Here, we report the outcomes of the BEMP technique using Tron stent retrievers for M2 occlusion thrombectomy.

Methods: Consecutive patients with AIS owing to M2 occlusion who underwent the BEMP technique using 2 × 15-mm or 4 × 20-mm Tron stent retrievers were included. The technique involves deploying a Tron stent retriever through a 0.0165-inch microcatheter, followed by microcatheter removal and blind navigation of a 3MAX or 4MAX aspiration catheter over the bare Tron delivery wire until the aspiration catheter reaches the clot. A Tron stent retriever is inserted into the aspiration catheter like a cork and subsequently pulled as a unit. We assessed procedural outcomes [first-pass expanded thrombolysis in cerebral infarction (eTICI) score 2c/3 and 2b/2c/3], safety outcomes [symptomatic intracranial hemorrhage (sICH)], and clinical outcomes (good outcome rate defined as modified Rankin Scale score 0–2 at 90 days and mortality at 90 days).

Results: Eighteen M2 vessels were treated in 15 patients (six female, median age: 80 years, and median National Institutes of Health Stroke Scale score: 18). The BEMP technique was performed successfully in all cases. Whether to use a 3MAX or 4MAX catheter was determined by considering one of the following target vessels: dominant, non-dominant, or co-dominant M2 (3MAX, n = 9; 4MAX, n = 9). The first-pass eTICI 2c/3 and 2b/2c/3 rates were 47 (7/15) and 60% (9/15), respectively; sICH was not observed. Seven patients (47%) achieved good outcomes, and one patient (7%) died within 90 days.

Conclusions: The Tron stent retriever was safely and effectively used in the BEMP technique for acute MCA M2 occlusion and can be combined with a 0.0165-inch microcatheter, which may be useful for treating MeVO, in general.

Favorable first-pass recanalization rates with NeVa™ thrombectomy device in acute stroke patients: Initial clinical experience

BACKGROUND

The NeVa™ thrombectomy device (Vesalio LLC, Nashville, USA) has been reported to succeed in large vessel occlusion thrombectomy in animal, in-vitro, and clinical studies. Designed with Drop Zone technology, a closed distal tip, and strong expansive radial force, the device demonstrated particular efficiency in resistant "white" thrombi in preclinical research. Our goal is to determine the safety and performance of this novel stent retriever on first-pass rates and overall recanalization.

METHODS

The Interventional Neurology Database is a prospectively maintained database of anterior and posterior circulation stroke thrombectomy cases. We retrospectively analyzed cases where the NeVa™ thrombectomy device was used as the first-line treatment strategy. Data collection occurred between January 2019 and January 2020. First-pass recanalization, final recanalization, 90-day functional outcome, complication, and bleeding rates are reported.

RESULTS

One hundred eighteen patients were treated with the NeVa™ thrombectomy device. The mean patient age was 69 ± 14 years, the median baseline National Institutes of Health Stroke Scale was 14, and the median initial Alberta Stroke Program Early Computed Tomography score was 8. The median time from groin puncture to successful recanalization was 29 min (interquartile range (IQR): 20-40). First-pass recanalization rates were 56.8% (modified treatment in cerebral infarction (mTICI) 2b/3) and 44.9% (mTICI 2c/3). Final successful recanalization rate was 95.8% (thrombolysis in cerebral infarction 2b/3). Favorable functional outcome (modified Rankin Scale 0-2) was 53% in the "first-pass" subgroup and 42.4% in the total patient population. The median number of passes to achieve the final recanalization score was 1 (IQR 1-2). The rate of embolization into new territory was 1.7%. Four patients (3.3%) had symptomatic hemorrhage.

CONCLUSIONS

In our experience, the NeVa™ device demonstrated high first-pass and overall recanalization rates along with a good safety profile.

Systematic review and meta-analysis of current rates of first pass effect by thrombectomy technique and associations with clinical outcomes

BACKGROUND

First pass effect (FPE) in mechanical thrombectomy is thought to be associated with good clinical outcomes.

OBJECTIVE

To determine FPE rates as a function of thrombectomy technique and to compare clinical outcomes between patients with and without FPE.

METHODS

In July 2020, a literature search on FPE (defined as modified Thrombolysis in Cerebral Infarction (TICI) 2c-3 after a single pass) and modified FPE (mFPE, defined as TICI 2b-3 after a single pass) and mechanical thrombectomy for stroke was performed. Using a random-effects meta-analysis, we evaluated the following outcomes for both FPE and mFPE: overall rates, rates by thrombectomy technique, rates of good neurologic outcome (modified Rankin Scale score ≤2 at day 90), mortality, and symptomatic intracerebral hemorrhage (sICH) rate.

RESULTS

Sixty-seven studies comprising 16 870 patients were included. Overall rates of FPE and mFPE were 28% and 45%, respectively. Thrombectomy techniques shared similar FPE (p=0.17) and mFPE (p=0.20) rates. Higher odds of good neurologic outcome were found when we compared FPE with non-FPE (56% vs 41%, OR=1.78) and mFPE with non-mFPE (57% vs 44%, OR=1.73). FPE had a lower mortality rate (17% vs 25%, OR=0.62) than non-FPE. FPE and mFPE were not associated with lower sICH rate compared with non-FPE and non-mFPE (4% vs 18%, OR=0.41 for FPE; 5% vs 7%, OR=0.98 for mFPE).

CONCLUSIONS

Our findings suggest that approximately one-third of patients achieve FPE and around half of patients achieve mFPE, with equivalent results throughout thrombectomy techniques. FPE and mFPE are associated with better clinical outcomes.

A direct aspiration first-pass technique (ADAPT) versus stent retriever for acute ischemic stroke (AIS): a systematic review and meta-analysis

BACKGROUND AND PURPOSE

There is an ongoing debate about whether a direct aspiration first-pass technique (ADAPT) or stent retriever should be used as the first-pass mechanical thrombectomy device for patients with acute ischemic stroke (AIS). This meta-analysis aimed to compare the safety and efficacy of ADAPT versus stent retriever in patients with AIS.

METHODS

Structured searches on the PubMed, Embase, and Cochrane Library databases were conducted through July 2020. The primary outcomes of this study were: successful and complete recanalization; excellent and favorable outcomes; all-cause mortality at 90 days; and symptomatic intracerebral hemorrhage (sICH). The secondary outcomes of this study were: successful recanalization by primary chosen device; additional therapy; occurrence of emboli in a new territory; hemorrhagic complication; hemorrhagic infarction; parenchymatous hematoma; and subarachnoid hemorrhage. The odds ratios (ORs) with 95% confidence intervals (CIs) of the primary and secondary outcomes were calculated using a random-effects model. I² statistics were used to assess the heterogeneity for each outcome among the included studies.

RESULTS

Finally, 20 studies with a total of 6311 patients were included in our meta-analysis. There were no significant differences between the ADAPT group and the stent retriever group of the primary and secondary outcomes except additional therapy. Our pooled results indicated that patients in the ADAPT group needed more additional therapy than those in the stent retriever group (OR 2.24, 95% CI 1.41-3.57).

CONCLUSION

In conclusion, our meta-analysis showed similar clinical outcomes of ADAPT and stent retriever. However, patients in the ADAPT group had higher additional therapy rates than those in the stent retriever group. Due to several inevitable limitations of this meta-analysis, more large-scale randomized controlled trials are required to further investigate this topic.

Mechanical Thrombectomy in Acute Ischemic Stroke: A Meta-Analysis of Stent Retrievers vs Direct Aspiration vs a Combined Approach

BACKGROUND

Recent randomized control trials (RCTs) established that mechanical thrombectomy is superior to medical therapy for patients with stroke due to a large vessel occlusion.

OBJECTIVE

To compare the safety and efficacy profile of the different mechanical thrombectomy strategies.

METHODS

A random-effects meta-analysis was performed and the I2 statistic was used to assess heterogeneity according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

RESULTS

Nineteen studies with a total of 2449 patients were included. No differences were identified between the stent retrieval and direct aspiration groups in terms of modified Thrombolysis in Cerebral Infarction (mTICI) 2b/3 and mTICI 3 recanalization rates, and favorable outcomes (modified Rankin Scale [mRS] ≤ 2). Adverse event rates, including 90-d mortality, symptomatic intracerebral hemorrhage (sICH), and subarachnoid hemorrhage (SAH), were similar between the stent retrieval and direct aspiration groups. The use of the stent retrieval was associated with a higher risk of vasospasm (odds ratio [OR]: 2.98; 95% confidence interval [CI]: 1.10-8.09; I2: 0%) compared to direct aspiration. When compared with the direct aspiration group, the subgroup of patients who underwent thrombectomy with the combined approach as a first-line strategy had a higher likelihood of successful mTICI 2b/3 (OR: 1.47; 95% CI: 1.02-2.12; I2: 0%) and mTICI 3 recanalization (OR: 3.65; 95% CI: 1.56-8.54), although with a higher risk of SAH (OR: 4.33; 95% CI: 1.15-16.32).

CONCLUSION

Stent retrieval thrombectomy and direct aspiration did not show significant differences. Current available evidence is not sufficient to draw conclusions on the best surgical approach. The combined use of a stent retriever and aspiration as a first-line strategy was associated with higher mTICI 2b/3 and mTICI 3 recanalization rates, although with a higher risk of 24-h SAH, when compared with direct aspiration.

Y-Stent Rescue Technique for Failed Thrombectomy in Patients With Large Vessel Occlusion: A Case Series and Pooled Analysis

Objective: Y-stent thrombectomy is a recent rescue technique for failed thrombectomy in patients with emergent large vessel occlusion. We presented case series of using Y-stent rescue technique at different sites and investigate its feasibility and safety through pooled analysis of collected case report or series. Methods: Twenty-eight cases were screened from stroke databank who underwent thrombectomy between January 2015 and June 2019. Clinical, procedural, and follow-up data were investigated and pooled analysis of published literature was analyzed. Results: The occlusion sites include carotid terminus in 14 patients; siphon segment in 3; middle cerebral artery (MCA) in 4; basilar terminus in 7. The overall recanalization rate reached 85.7% (arterial occlusive lesion score 2-3); and final reperfusion rate 85.7% (modified Thrombolysis in Cerebral Infarction 2b-3). After literature review, totally, 52 cases were included. Good clinical outcome was achieved in 26 (50%) and mortality in 7 (17.3%). There is no significant difference on the SAH complication at different sites. Literature review shows no difference between each site in the reperfusion and complication rate. Conclusion: Our case series results suggest that high recanalization rate can be effectively achieved with Y-stent rescue technique for patients with refractory emergent large vessel occlusion. The safety of using this technique at different sites needs further investigation for patients.

Effectiveness and Technical Considerations of Solitaire Platinum 4×40 mm Stent Retriever in Mechanical Thrombectomy with Solumbra Technique

OBJECTIVE

The Solitaire Platinum 4×40 mm stent retriever contains radiopaque markers with a long length. We evaluated the effect of Solitaire Platinum 4×40 mm stent retriever in Solumbra technique thrombectomy, and compared it with shorter Solitaire stent retrievers.

METHODS

A total of 70 patients who underwent Solumbra technique thrombectomy with equal diameter (4 mm) and different length (40 vs. 20 mm) Solitaire stent retrievers were divided into two groups : the Solitaire Platinum 4×40 mm stent (4×40) group and the Solitaire FR 4×20 mm stent or Solitaire Platinum 4×20 mm stent (4×20) group. The clinical outcomes, Thrombolysis in Cerebral Infarction score, the first pass reperfusion status, and complications were evaluated and compared between the two groups. Multivariate analysis was performed to evaluate the predictive factors for reperfusion and complete reperfusion from the first pass.

RESULTS

Higher first-pass reperfusion and complete reperfusion were achieved in the 4×40 group (68.0% and 48.0%) than in the 4×20 group (46.7% and 33.3%; p=0.004 and 0.007, respectively). In multivariate analysis, radiopaque device and longer stent retriever were correlated with first-pass reperfusion (p=0.014 and 0.008, respectively) and first-pass complete reperfusion (p=0.022 and 0.012, respectively).

CONCLUSION

Our study demonstrated the usefulness of the Solitaire Platinum 4×40 mm stent retriever, which led to higher firstpass reperfusion and complete reperfusion rates than the Solitaire FR 4×20 mm stent or the Solitaire Platinum 4×20 mm stent, especially in Solumbra technique thrombectomy.

Tandem stents thrombectomy as a rescue treatment for refractory large vessel occlusions

BACKGROUND

Mechanical thrombectomy with a stent retriever (SR) and/or aspiration is the 'gold standard' for the treatment of acute ischemic stroke due to large vessel occlusion (LVO). However, sometimes clots may not be retrievable with a single SR alone or combined with aspiration.

OBJECTIVE

To assess the safety and efficacy of a novel tandem stents thrombectomy (TST) technique as a rescue treatment for acute LVO that is refractory to conventional attempts.

METHODS

All patients treated with the TST technique as rescue treatment after failure of conventional attempts were retrospectively reviewed. The postprocedural angiographic and clinical outcome, including modified Thrombolysis in Cerebral infarction (mTICI) grade, National Institutes of Health Stroke Scale (NIHSS) score, and modified Rankin Scale (mRS) score, was assessed.

RESULTS

Nine patients (mean age, 65.2 years; median NIHSS score 18) with middle cerebral artery M1 segment (n=6) and terminal internal carotid artery (n=3) occlusions were included in the study. The TST technique was performed as a rescue treatment after unsuccessful stent thrombectomy alone (four cases) and stent thrombectomy plus aspiration (five cases). Successful recanalization (mTICI 2b/3) was achieved in all patients. No procedure-related complications occurred except reversible vasospasms were observed in three patients and one patient developed hemorrhage transformation after the procedure, but was asymptomatic. Three patients had good clinical outcome (mRS score 0-2 at 90 days). Two patients (22.2%) died.

CONCLUSIONS

The TST technique seems to be a safe and effective rescue treatment for acute LVO that is refractory to conventional attempts.

Direct aspiration stroke thrombectomy: a comprehensive review

Mechanical thrombectomy is now the standard of care for acute ischemic stroke patients with large vessel occlusions, and can be performed with several devices and techniques. One of these techniques, direct aspiration (DA), consists of navigating a large-bore catheter up to the face of the clot and initiating forceful suction. This comprehensive review has three objectives: (1) to describe the direct aspiration technique; (2) to present the available evidence regarding predictive factors of DA success and performance compared with other techniques; and (3) to discuss the forthcoming improvements in distal aspiration.

Repeated mechanical thrombectomy in short-term large vessel occlusion recurrence: multicenter study and systematic review of the literature

BACKGROUND

Data on the frequency and outcome of repeated mechanical thrombectomy (MT) in patients with short-term re-occlusion of intracranial vessels is limited. Addressing this subject, we report our multicenter experience with a systematic review of the literature.

METHODS

A retrospective analysis was conducted of consecutive acute stroke patients treated with MT repeatedly within 30 days at 10 tertiary care centers between January 2007 and January 2020. Baseline demographics, etiology of stroke, angiographic outcome and clinical outcome evaluated by the modified Rankin Scale (mRS) at 90 days were noted. Additionally, a systematic review of reports with repeated MT due to large vessel occlusion (LVO) recurrence was performed.

RESULTS

We identified 30 out of 7844 (0.4%) patients who received two thrombectomy procedures within 30 days due to recurrent LVO. Through systematic review, three publications of 28 participants met the criteria for inclusion. Combined, a total of 58 participants were analyzed: cardioembolic events were the most common etiology for the first (65.5%) and second LVO (60.3%), respectively. Median baseline NIHSS (National Institutes of Health Stroke Scale) was 13 (IQR 8-16) before the first MT and 15 (IQR 11-19) before the second MT (p=0.031). Successful reperfusion was achieved in 91.4% after the first MT and in 86.2% patients after the second MT (p=0.377). The rate of functional independence (mRS 0-2) was 46% at 90 days after the second procedure.

CONCLUSION

Repeated MT in short-term recurrent LVO is a rarity but appears to be safe and effective. The second thrombectomy should be pursued with the same extensive effort as the first procedure as these patients may achieve similar good outcomes.

Impact of early division of the middle cerebral artery on outcome following mechanical thrombectomy

BACKGROUND

Mechanical thrombectomy has become the standard care for acute ischemic stroke caused by large vessel occlusion. However, complete reperfusion cannot be achieved in all cases, and several factors influencing the results of mechanical thrombectomy have been investigated. Among others, a tortuous anatomy is associated with lower rates of complete reperfusion. We aimed to investigate whether an early division of the middle cerebral artery has an impact on reperfusion results in mechanical thrombectomy.

METHODS

Retrospective review of consecutive patients with M1 occlusion treated endovascularly between January 2016 and December 2019 at three tertiary care centers. The study group was dichotomized based on the length of the M1 segment. Early division of the middle cerebral artery was defined as a maximum length of 10 mm of the M1 segment. Primary endpoints were first-pass mTICI scores of 3, ≥2c, and ≥2b. Secondary endpoints contained final reperfusion, number of device-passes, time interval from groin puncture to reperfusion, rate of postinterventional symptomatic intracranial hemorrhage, and frequency of emboli of new territory.

RESULTS

Among 284 included patients, 70 presented with an early division of the M1 segment (25%). Reperfusion results did not differ significantly between early and late division of M1. A higher rate of symptomatic intracranial hemorrhage was found in the group with an early M1 division treated with aspiration only (14.3% vs. 0%; p = 0.013). Patients with late M1 division had a significantly higher rate of large artery sclerosis (19.2% vs. 8.6%, p = 0.039).

CONCLUSION

The anatomic variant of an early division of the middle cerebral artery was not a predictor for incomplete reperfusion.

Initial Results of Management for Acute Ischemic Stroke due to Large Vessel Occlusion by a Direct Aspiration First Pass Technique at a Vietnamese Hospital

Background:

The development of novel revascularization devices has improved procedural and clinical outcomes in acute ischemic stroke (AIS). A direct aspiration first pass technique (ADAPT) has been introduced as a rapid simple method for achieving good recanalization and clinical outcomes using large bore aspiration catheters in the treatment of AIS due to large vessel occlusion (LVO).

Objectives:

The aim of this study was to assess the safety and efficacy of ADAPT in the treatment of AIS due to LVO in the Vietnamese patient population.

Materials and Methods:

A retrospective analysis of a hospital database was conducted on all patients undergoing stroke therapy with the ADAPT technique at the institution from January 2017 to December 2017. Efficacy and safety were evaluated by the variables: revascularization rates (thrombolysis in cerebral infarction [TICI] score), time to revascularization, procedural complications, and clinical outcomes (modified Rankin scale [mRS] score) at the 90-day follow-up visit.

Results:

From the database review, 37 AIS patients treated with ADAPT were identified. The mean NIHSS score at presentation was 17.3 and improved to 8.9 at discharged. The average time arterial puncture to revascularization was 32.5 min. TICI 2b/3 revascularization was achieved in 30/37 (81.1%) patients, good clinical outcomes were achieved (mRS 0–2) in 21/37 (56.7%) patients, and mortality rate was 6/37 (16.2%) during follow-up.

Conclusions:

ADAPT utilizing large bore aspiration catheters appears to be a fast, simple, safe, and effective method for the management of AIS in the Vietnamese patient population.

Mechanical Thrombectomy: Answering Unanswered

The stroke physician community witnessed a major “breakthrough” in acute stroke therapeutics when the results of the first of the many positive trials, “MR CLEAN,” were published showing a significant absolute benefit in favor of mechanical thrombectomy in patients with large vessel occlusion (LVO). Thereafter, the investigators of ESCAPE, SWIFT PRIME, REVASCAT, THRACE, and PISTE concluded the same. Based on the initial studies, the American Stroke Association amended the 2013 guidelines in 2015 to include mechanical thrombectomy as the standard of care in patients with LVO presenting within six hours. In the past year, the horizon was further expanded when two major landmark trials, DAWN and DEFUSE 3, established the benefit of mechanical thrombectomy in the delayed window period in a select group of patients. It further led to the inclusion of the delayed window period treatment strategies in the 2018 guidelines. However, there are many unanswered questions in scenarios like small deficit with LVO, borderline large core, wake-up stroke (WUS), tandem occlusion, imaging of choice, conscious sedation (CS) versus general anesthesia (GA), and choice of technique. In our review, we aim to answer these questions along with a schematic representation of current techniques used in stroke thrombectomy.

Endovascular Thrombectomy of Calcified Emboli in Acute Ischemic Stroke: A Multicenter Study

BACKGROUND AND PURPOSE

Large intracranial vessel occlusion due to calcified emboli is a rare cause of major stroke. We assessed the prevalence, imaging appearance, the effectiveness of mechanical thrombectomy, and clinical outcome of patients with large-vessel occlusion due to calcified emboli.

MATERIALS AND METHODS

We performed a retrospective analysis of clinical and procedural data of consecutive patients who underwent mechanical thrombectomy due to calcified emboli in 7 European stroke centers.

RESULTS

We screened 2969 patients, and 40 patients matched the inclusion criteria, accounting for a prevalence of 1.3%. The mean maximal density of the thrombus was 327 HU (range, 150-1200 HU), and the mean thrombus length was 9.2 mm (range, 4-20 mm). Four patients had multiple calcified emboli, and 2 patients had an embolic event during an endovascular intervention. A modified TICI score of ≥2b was achieved in 57.5% (23/40), with minimal-to-no reperfusion (modified TICI 0-1) in 32.5% (13/40) and incomplete reperfusion (modified TICI 2a) in 10% (4/40). Excellent outcome (mRS 0-1) was achieved in only 20.6%, functional independence (mRS 0-2) in 26.5% and 90-day mortality was 55.9%.

CONCLUSIONS

Acute ischemic stroke with large-vessel occlusion due to calcified emboli is a rare entity in patients undergoing thrombectomy, with considerably worse angiographic outcome and a higher mortality compared with patients with noncalcified thrombi. Good functional recovery at 3 months can still be achieved in about a quarter of patients.

Blind exchange with mini-pinning technique for distal occlusion thrombectomy

Introduction

Technical improvements to enhance distal occlusion thrombectomy are desirable. We describe the blind catheter exchange technique and report the pinning technique with small devices (‘mini-pinning’) for distal occlusions.

Methods

A retrospective review of a prospective database from January 2015 to August 2018 was performed for cases of distal occlusion in which the ‘blind exchange/mini-pinning’ (BEMP) techniques were used. The technique involves the deployment of a 3 mm Trevo retriever followed by microcatheter removal and blind advancement of a 3MAX aspiration catheter over the bare retriever delivery wire (‘blind exchange’) until clot contact under aspiration. The retriever is subsequently partially recaptured in order to ‘cork’ the thrombus (‘mini-pinning’) and the system pulled as a unit. Patients with distal occlusions treated with BEMP and standard techniques (either 3 mm Trevo or 3MAX) were compared.

Results

Twenty-five vessels were treated in 22 patients. The majority of patients had isolated distal occlusions predominantly in the distal middle cerebral artery (MCA) segments, half of which involved the superior division. The comparison between BEMP (n=25 vessels) and standard techniques (n=144 vessels) revealed balanced groups. One of the highlighted differences was the more distal MCA occlusions among those who underwent BEMP (M3 occlusions 52% vs 22%; p=0.001). Otherwise, the vessel, segments, divisions and luminal diameter were comparable. There was a higher rate of first-pass modified Thrombolysis in Cerebral Infarction 2b–3 (80% vs 56%; p=0.03) and a trend towards higher rates of first-pass full reperfusion (60% vs 40%; p=0.07) with BEMP compared with standard techniques. Final reperfusion and clinical outcomes were comparable.

Conclusion

BEMP appears to be a safe and effective technique for the treatment of distal occlusions. Additional studies are warranted.

Beyond the first pass: revascularization remains critical in stroke thrombectomy

BACKGROUND

The first pass effect has been recently reported as a predictor of good clinical outcome after stroke thrombectomy. We evaluate the first pass effect on outcome and the influence of revascularization in these and other patients.

METHODS

We performed a retrospective analysis of a prospectively maintained database on anterior cerebral circulation stroke thrombectomy cases from April 2012 to April 2018. Data compiled included patient demographics, presenting National Institutes of Health Stroke Scale score, vessel occlusion site, thrombectomy procedural details, and 90 day modified Rankin Scale scores.

RESULTS

205 patients were included. The numbers of patients who underwent one, two, three, four, five, and six passes were 69, 70, 55, 9, 1, and 1, respectively. Successful revascularization was achieved in 87%, 83%, and 64% of patients in the one, two, and 3 or more passes groups, respectively (p=0.002). Good functional outcome was inversely correlated with number of passes when comparing the one, two, and three or more passes groups (54%, 43%, 29%; P=0.014). In patients with full revascularization, there was no significant difference in good functional outcomes between the one, two, and three or more passes groups (64%, 65%, 50%; P=0.432). Number of passes was not an independent negative predictor of good clinical outcome (OR 1.66, 95% CI 0.82 to 3.39; P=0.165).

CONCLUSIONS

First pass thrombectomy patients have better functional outcomes compared with beyond-first pass patients. This effect is related at least in part to a higher rate of revascularization in one pass patients. Revascularization beyond the first pass should continue to be the goal of stroke thrombectomy.

Endovascular treatment of acute ischaemic stroke in octogenarians and nonagenarians compared with younger patients

Purpose: Endovascular therapy for emergent large vessel occlusion has been established as the standard approach for acute ischaemic stroke. However, the effectiveness and safety of endovascular therapy in the very elderly population has not been proved. Objective: To determine the safety and effectiveness of endovascular therapy in octogenarians and nonagenarians. Methods: We retrospectively reviewed all patients who underwent endovascular therapy at two stroke centres between April 2012 and July 2018. Functional outcome was assessed using the modified Rankin scale at 90 days after stroke or at discharge. A favourable outcome was defined as a modified Rankin scale score of 0-2 or not worsening of the modified Rankin scale score before stroke. Outcome was compared between younger patients (aged 46-79 years, n = 40) and octogenarians and nonagenarians (aged 80-97 years, n = 19). Results: Octogenarian and nonagenarian patients had pre-stroke functional deficit (modified Rankin scale score >1) more frequently than younger patients (57.9% vs. 20.0%, respectively, P = 0.0059). No difference was observed between very elderly and younger patients in the rate of successful reperfusion (89.5% vs. 67.5%, respectively, P = 0.11), favourable functional outcome (47.4% vs. 45.0%, respectively, P = 1.00) and mortality (21.1% vs. 27.5%, respectively, P = 1.00). On multiple regression analysis, successful reperfusion, concomitant use of intravenous thrombolysis, and out-of-hospital onset were independent predictors of favourable outcome (P = 0.0003, 0.015 and 0.028, respectively). Conclusions: Successful reperfusion, concomitant use of intravenous thrombolysis, and out-of-hospital onset were clinical predictors of favourable outcome. However, we did not observe an age-dependent effect of clinical outcome after endovascular therapy.

Stent-retriever assisted vacuum-locked extraction (SAVE) versus a direct aspiration first pass technique (ADAPT) for acute stroke: data from the real-world

BACKGROUND

Embolectomy is the standard of care in acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). Aim of this study was to compare two techniques: A Direct Aspiration First Pass Technique (ADAPT) and Stent-retriever Assisted Vacuum-locked Extraction (SAVE) stratified by the occluded vessel.

METHODS

One hundred seventy-one patients (71 male) treated between January 2014 and September 2017 with AIS due to LVO of the anterior circulation (55 carotid T, 94 M1, 22 M2) were included. Treatment techniques were divided into two categories: ADAPT and SAVE. Primary endpoints were successful reperfusion (mTICI ≥2b), near-perfect reperfusion (mTICI ≥2c) and groin puncture to reperfusion time. Secondary endpoints were the number of device-passes, first-pass reperfusion, the frequency of emboli to new territory (ENT), clinical outcome at 90 days, and the frequency of symptomatic intracranial hemorrhage (sICH). Analysis was performed on an intention to treat basis.

RESULTS

Overall, SAVE resulted in significant higher rates of successful reperfusion (mTICI≥2b) compared to ADAPT (93.5% vs 75.0%; p = 0.006). After stratification for the occluded vessel only the carotid T remained significant with higher rates of near-perfect reperfusion (mTICI≥2c) (55.2% vs 15.4%; p = 0.025), while for successful reperfusion a trend remained (93.1% vs 65.4%; p = 0.10). Groin to reperfusion times were not significantly different. Secondary analysis revealed higher rates of first-pass successful reperfusion (59.6% vs 33.3%; p = 0.019), higher rates of first-pass near-perfect reperfusion in the carotid T (35.4% vs 16.7%; p = 0.038) and a lower number of device-passes overall (median 1 IQR 1-2 vs 2 IQR 2-3; p <  0.001) and in the carotid T (median 2 IQR 1.3 vs 3 IQR 2-5; p <  0.001) for SAVE. Clinical outcome and safety parameters were comparable between groups.

CONCLUSIONS

Embolectomy using SAVE appears superior to ADAPT, especially for carotid T occlusions with regard to reperfusion success.

Factors impacting on technical success in stroke thrombectomy: experience of a UK neuro-interventional unit

AIM

To investigate factors that could impact on recanalisation and reperfusion in patients undergoing mechanical thrombectomy and to assess the technical success over time.

MATERIALS AND METHODS

Two hundred consecutive patients who underwent thrombectomy for a proximal anterior circulation occlusion were dichotomised into equal groups (groups 1 and 2) based on the date that immediate access to emergency general anaesthesia (GA) commenced.

RESULTS

Recanalisation success using thrombolysis in cerebral infarction (TICI) 2b/3 or TICI 2c/3 significantly improved in group 2 (67% versus 93%, p<0.0001; 52% versus 78%, p=0.0002). Symptomatic haemorrhage also reduced from 9% to 4%. Despite similar presentation Alberta Stroke Program Early (computed tomography) CT Scores (ASPECTS), post-procedural ASPECTS was significantly increased in group 2 (7; [interquartile range {IQR} 4-9] versus 8 [IQR 7-9]; p=0.0034). The number of patients with a post procedural ASPECTS of 8-10 increased (46% versus 64%, p=0.0155) and the difference in ASPECTS between pre- and post-thrombectomy CT was significantly lower (2 [IQR 1-4] versus 1 [IQR 0-2], p<0.0001). GA use increased from 8% to 56% (p=0.0001) as did use of distal aspiration (59% versus 87%, p=0.0001) mostly in combination with a stent-retriever. Failed access fell from 8% to 3%. When GA was used, successful recanalisation (TICI 2b/3) was achieved more frequently (90.5% versus 76.7%; OR 3.04, 1.2-7.69, p=0.0187).

CONCLUSION

Technical results for thrombectomy are improving over time. Technique modification, operator experience, and judicious use of GA may be contributing.

First-line contact aspiration vs stent-retriever thrombectomy in acute ischemic stroke patients with large-artery occlusion in the anterior circulation: Systematic review and meta-analysis

BACKGROUND

In acute ischemic stroke patients with large-artery occlusion, uncertainties remain about whether clinically important outcomes are comparable between first-line contact aspiration and stent-retriever thrombectomy, although two trials have investigated whether one strategy should be preferred over another.

PURPOSE

The purpose of this article is to compare the efficacy and safety of first-line contact aspiration and stent-retriever thrombectomy in stroke patients with anterior circulation large-artery occlusion.

METHODS

We undertook a systematic review of studies of patients treated for large-artery occlusion, with the latest devices of either strategy, within six hours of stroke onset. We determined rates of final complete reperfusion (defined as modified Thrombolysis In Cerebral Infarction score = 3), periprocedural complications and 90-day functional independence (defined as modified Rankin Scale (mRS) score 0-2), and excellent outcome (defined as mRS score 0-1) after contact aspiration and after stent-retriever thrombectomy using random-effects meta-analyses. Any differential effects in rates between the two strategies were assessed using random-effects meta-regressions.

RESULTS

Fifteen studies (1817 patients) were included. There was no difference in rates of final complete reperfusion at the end of all endovascular procedures between contact aspiration and stent retrievers (51.1%, 95% confidence interval (CI) 39.3-62.9; vs 38.3%, 95% CI 28.6-48.0; p_int = 0.14), 90-day functional independence (45.0%, 40.7-49.2; vs 52.4%, 47.7-57.1; p_int = 0.45) and excellent outcome (32.1%, 25.7-38.5; vs 34.1%, 21.2-46.9; p_int = 0.94). Rates of periprocedural complications did not differ between the two strategies.

CONCLUSIONS

Current data suggest no difference in efficacy and safety between first-line contact aspiration and stent-retriever thrombectomy in stroke patients with large-artery occlusion.

Preventing vessel perforations in endovascular thrombectomy: feasibility and safety of passing the clot with a microcatheter without microwire: the wireless microcatheter technique

BACKGROUND

To place a stent retriever for thrombectomy in acute ischemic stroke, the clot has to be passed first. A microwire is usually used for this maneuver. As an alternative, a wireless microcatheter can be used to pass the clot.

OBJECTIVE

To analyze the feasibility and complication rates of passing the clot using either a microwire or a wireless microcatheter.

METHODS

A retrospective non-randomized analysis of 110 consecutive patients with acute ischemic stroke in the anterior circulation was performed, in whom video recordings of mechanical thrombectomies were available. In total, 203 attempts at mechanical recanalization were performed.

RESULTS

Successful recanalization (TICI 2b-3) was achieved in 97.3% of patients. In 71.8% of attempts the clot was successfully passed using a wireless microcatheter only. When a microwire was used initially, clot passage was successful in 95.3% of attempts. Complication rates for angiographically detectable subarachnoid hemorrhage were 6.1% when a microwire was used to pass the clot compared with 0% when a wireless microcatheter was used (p<0.001). Complication rates for angiographically occult circumscribed subarachnoid contrast extravasation observed on post-interventional CT scans were 18.2% when a microwire was used to pass the clot and 4.5% when a wireless microcatheter was used (p<0.001).

CONCLUSIONS

In most cases of mechanical recanalization the clot can be passed with a wireless microcatheter instead of a microwire. In our study this method significantly reduced the risk for vessel perforation and subarachnoid hemorrhage. We therefore recommend the use of this technique whenever possible.

A systematic review and meta-analysis of observational evidence for the use of bailout self-expandable stents following failed anterior circulation stroke thrombectomy

BACKGROUND

The crucial role of thrombectomy in the management of emergent large vessel occlusive stroke is not disputed but there is a technical failure rate in a significant minority of patients whose outcomes are often poor. Our objective was to perform a systematic review and meta-analysis to assess the safety and efficacy of permanent self-expandable stent deployment as a bailout procedure in cases of failed anterior circulation thrombectomy.

METHODS

Two independent reviewers searched the Pubmed (Medline) database for studies reporting outcomes following failed endovascular thrombectomy with subsequent rescue therapy employing self-expandable stents.

RESULTS

Eight studies (one prospective, seven retrospective) originating from Europe, Asia, and America comprising 160 patients met the inclusion criteria. Estimated baseline National Institutes of Health Stroke Scale score was 17.1 (95% CI 15.7 to 18.4). Following failed thrombetcomy and stent deployment, the rate of favorable outcome (modified Rankin Scale score 0-2) was 43% (95% CI 34% to 53%). Pooled mortality was 21% (95% CI 13% to 33%). Successful recanalization (Thrombolysis in Cerebral Infarction (TICI) 2b-3 or Thrombolysis in Myocardial Infarction (TIMI) 2-3) was 71% (95% CI 63% to 77%). Symptomatic intracerebral hemorrhage was seen in 12% (95% CI 7% to 18%). The Solitaire stent (Medtronic) was the most commonly deployed stent following failed thrombectomy attempts (66%; 95% CI 31% to 89%). Pre- or post-stent angioplasty was performed in 39%of patients (95% CI 29% to 48%). Glycoprotein IIb/IIIa inhibitors were used in 89% (95% CI 71% to 97%). 95% of patients received postprocedural antiplatelet therapy.

CONCLUSION

A rescue stent procedure seems reasonable as a last resort following failed thrombectomy but currently the level of evidence is limited. Prospective registries may aid in guiding future recommendations.

Outcomes of Stent Retriever versus Aspiration-First Thrombectomy in Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

There is ongoing debate regarding the optimal first-line thrombectomy technique for large-vessel occlusion.

PURPOSE

We performed a systematic review and meta-analysis of comparative studies on stent retriever-first and aspiration-first thrombectomy.

DATA SOURCES

We searched Ovid MEDLINE, PubMed, and EMBASE from 2009 to February 2018.

STUDY SELECTION

Two reviewers independently selected the studies. The primary end point was successful reperfusion (TICI 2b/3).

DATA ANALYSIS

Random-effects meta-analysis was used for analysis.

DATA SYNTHESIS

Eighteen studies including 2893 patients were included. There was no significant difference in the rate of final successful reperfusion (83.9% versus 83.3%; OR = 0.87; 95% CI, 0.62%-1.27%) or good functional outcome (mRS 0-2) at 90 days (OR = 1.07; 95% CI, 0.80-1.44) between the stent-retriever thrombectomy and aspiration groups. The stent-retriever thrombectomy-first group achieved a statistically significant higher TICI 2b/3 rate after the first-line device than the aspiration-first group (74.9% versus 66.4%; OR = 1.53; 95% CI, 1.14%-2.05%) and resulted in lower use of a rescue device (19.9% versus 32.5%; OR = 0.36; 95% CI, 0.14%-0.90%). The aspiration-first approach resulted in a statistically shorter groin-to-reperfusion time (weighted mean difference, 7.15 minutes; 95% CI, 1.63-12.67 minutes). There was no difference in the number of passes, symptomatic intracerebral hemorrhage, vessel dissection or perforation, and mortality between groups.

LIMITATIONS

Most of the included studies were nonrandomized. There was significant heterogeneity in some of the outcome variables.

CONCLUSIONS

Stent-retriever thrombectomy-first and aspiration-first thrombectomy were associated with comparable final reperfusion rates and functional outcome. Stent-retriever thrombectomy was superior in achieving reperfusion as a stand-alone first-line technique, with lower use of rescue devices but a longer groin-to-reperfusion time.

Crossing Y-Solitaire thrombectomy as a rescue treatment for refractory acute occlusions of the middle cerebral artery

Background

Mechanical thrombectomy using a stent retriever has become the standard of care for acute large-vessel occlusions in the anterior circulation. Clots that are refractory to single stent retriever thrombectomy remain a challenge for neurointerventionalists.

Objective

To assess the efficacy and safety of double stent retriever (crossing Y-Solitaire) thrombectomy as a rescue treatment for acute middle cerebral artery (MCA) occlusions that are refractory to single stent retriever thrombectomy.

Methods

We retrospectively reviewed the databases of our hospitals to identify patients who presented with an acute MCA occlusion and were treated with crossing Y-Solitaire thrombectomy. The angiographic (Thrombolysis in Cerebral Infarction (TICI) scale) and clinical outcomes (National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) scores) and complications were assessed.

Results

Ten patients were included in the study. The median initial NIHSS score and Alberta Stroke Program Early CT Score (ASPECTS) were 19.0 and 9.6, respectively. Crossing Y-Solitaire thrombectomy was performed as a rescue technique after unsuccessful single Solitaire thrombectomy passes in all cases. Successful recanalization (TICI 2b/3) was achieved in 8 (80%) patients. We observed asymptomatic reperfusion hemorrhages in 2 (20%) patients. No procedural related complications were seen other than reversible vasospasms in 5 (50%) patients. Sixty percent of the patients had a mRS score of between 2 and 0 at 90 days after the procedure. There was no mortality.

Conclusion

Crossing Y-Solitaire thrombectomy seems to be an effective and safe alternative rescue technique to treat refractory MCA bifurcation occlusions that are refractory to standard thrombectomy procedures.

Stent retriever placement in embolectomy: the choice of the post-bifurcational trunk influences the first-pass reperfusion result in M1 occlusions

Background

Embolectomy using Stent retriever Assisted Vacuum-locked Extraction (SAVE) is effective in intracranial large vessel occlusion. Which post-bifurcational trunk should be chosen for distal stent retriever placement in M1 occlusions is, however, elusive.

Methods

We conducted a retrospective analysis of prospectively collected data from a comprehensive stroke center between 2015 and 2017. Eighty-nine consecutive patients with M1 occlusions were treated with SAVE. Digital subtraction angiography (DSA) series were studied to determine the anatomy of middle cerebral artery division, the position of the stent retriever, and to measure vessel diameters. The primary endpoint was first-pass complete/near-complete reperfusion, defined as a modified Thrombolysis in Cerebral Infarction (mTICI) score of 2c or 3, after distal stent retriever placement in the inferior trunk.

Results

In 76/89 (85%) patients, microcatheter series were documented. A microcatheter was placed within the inferior trunk in 30/76 (40%) cases. First-pass near-complete/complete reperfusion was more likely to be achieved when the inferior trunk was used for stent retriever placement rather than the superior trunk (mTICI ≥2c: 22/30 (73%) vs 22/46 (48%), P=0.034; and mTICI 3: 20/30 (67%) vs 17/46 (37%), P=0.018). Median diameter of the inferior trunk was larger than the superior trunk (1.4 mm (IQR 1.26–1.62) vs 1.18 mm (IQR 0.98–1.43), P=0.011). The inferior trunk was dominant in 56/76 (74%) cases. Successful reperfusion was associated with placement within the dominant trunk (33/40 (83%) vs 22/36 (61%), P=0.044).

Conclusion

The choice of the inferior trunk for distal stent retriever placement in M1 occlusions is associated with a high rate of first-pass near-complete/complete reperfusion when using SAVE.