Contact Aspiration Versus Stent Retriever in Patients With Acute Ischemic Stroke With M2 Occlusion in the ASTER Randomized Trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization)

Incidence and clinical outcomes of perforations during mechanical thrombectomy for medium vessel occlusion in acute ischemic stroke: A retrospective, multicenter, and multinational study

BACKGROUND

Mechanical thrombectomy (MT) has revolutionized the treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO), but its efficacy and safety in medium vessel occlusion (MeVO) remain less explored. This multicenter, retrospective study aims to investigate the incidence and clinical outcomes of vessel perforations (confirmed by extravasation during an angiographic series) during MT for AIS caused by MeVO.

METHODS

Data were collected from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. A total of 1373 AIS patients with MeVO underwent MT. Baseline characteristics, procedural details, and clinical outcomes were analyzed.

RESULTS

The incidence of vessel perforation was 4.8% (66/1373). Notably, our analysis indicates variations in perforation rates across different arterial segments: 8.9% in M3 segments, 4.3% in M2 segments, and 8.3% in A2 segments (p = 0.612). Patients with perforation had significantly worse outcomes, with lower rates of favorable angiographic outcomes (TICI 2c-3: 23% vs 58.9%, p < 0.001; TICI 2b-3: 56.5% vs 88.3%, p < 0.001). Functional outcomes were also worse in the perforation group (mRS 0-1 at 3 months: 22.7% vs 36.6%, p = 0.031; mRS 0-2 at 3 months: 28.8% vs 53.9%, p < 0.001). Mortality was higher in the perforation group (30.3% vs 16.8%, p = 0.008).

CONCLUSION

This study reveals that while the occurrence of vessel perforation in MT for AIS due to MeVO is relatively rare, it is associated with poor functional outcomes and higher mortality. The findings highlight the need for increased caution and specialized training in performing MT for MeVO. Further prospective research is required for risk mitigation strategies.

Endovascular thrombectomy versus intravenous thrombolysis for primary distal, medium vessel occlusion in acute ischemic stroke

Introduction

In the absence of clinical trials, the benefit of endovascular therapy (EVT) on the treatment of acute ischemic stroke (AIS) with primary distal and medium vessel occlusions (DMVO) is still not well defined. The aim of the study is to evaluate EVT with or without intravenous thrombolysis (EVT ± IVT) in primary DMVO stroke in comparison with a control cohort treated with IVT alone.

Methods

We analysed all consecutive AIS with proven primary DMVO. Primary endpoints were excellent outcome, functional independence at 3 months follow-up, and early neurologic improvement at 1 day after treatment.

Results

One hundred and fourteen patients with DMVO strokes were included between 2019 and 2023. Propensity-weighted analysis showed no significant differences in EVT ± IVT vs IVT for the excellent outcome (adjusted OR [aOR], 1.575; 95% CI, 0.706-3.513), functional independence (aOR, 2.024; 95% CI, 0.845-4.848), early neurological improvement (aOR, 2.218; 95% CI, 0.937-5.247), mortality (aOR, 0.498; 95% CI, 0.177-1.406), symptomatic intracranial haemorrhage (aOR, 0.493; 95% CI, 0.102-2.385), and subarachnoid haemorrhage (aOR, 0.560; 95% CI, 0.143-2.187). The type of revascularization did not influence the percentage of cerebral volume lost (adjusted linear regression estimate, -19.171, t value, 11.562; p = 0.104).

Conclusions

This study supports the hypothesis that patients with primary DMVO stroke treated with EVT (±IVT) or IVT alone have comparable outcomes.

Endovascular treatment of distal medium vessel occlusions using microcatheter aspiration thrombectomy

BACKGROUND AND PURPOSE

Recent studies suggest that endovascular treatment (EVT) in distal medium vessel occlusion (DMVO) stroke is beneficial even beyond middle cerebral artery (MCA) - M2 segment. However, data about aspiration thrombectomy of DMVOs is scarce since common state-of-the-art aspiration catheters are usually too large for small distal intracranial arteries. We report our initial experiences using the microcatheter aspiration thrombectomy (MAT) technique as frontline therapy for acute DMVOs in the MCA territory.

METHODS

We retrospectively analyzed all acute ischemic stroke (AIS) patients that underwent MAT of a primary or secondary DMVO in the M3 or M4 segment between January 2019 and October 2021. Recanalization rates, procedural safety and outcome data were recorded.

RESULTS

MAT of acute M3 and M4 occlusions was performed in 19 patients with AIS. Six had isolated DMVO strokes, 13 had secondary DMVOs during EVT of a proximal large vessel occlusion. Successful revascularization to DMVO TICI ≥ 2b was achieved in 58% (11/19) with a single pass in all of them. The median National Institutes of Health Strokes Scale (NIHSS) score at admission and discharge was 12 and 3, respectively. 68% (13/19) of the patients had a good clinical outcome at discharge (modified Rankin Scale 0-2). No symptomatic complications related to MAT occurred.

CONCLUSIONS

MAT of DMVOs in the MCA territory is technically feasible and effective. Compared to stent retriever-based thrombectomy in DMVOs the hemorrhagic complication rate appears notably lower. Further studies are needed to validate the benefit of mechanical thrombectomy in the distal intracranial vasculature.

Reperfusion strategies in stroke with medium-to-distal vessel occlusion: a prospective observational study

INTRODUCTION

Medium vessel occlusion (MeVO) accounts for 30% of acute ischemic stroke cases. The risk/benefit profile of endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) or the combination of the two (bridging therapy (BT)) is still unclear in MeVO. Here, we compare reperfusion strategies in MeVO for clinical and radiological outcomes.

METHODS

This prospective single center study enrolled consecutive patients with AIS due to primary MeVO undergoing IVT, EVT, or BT at a comprehensive stroke center. Primary outcome was good functional status, defined as modified Rankin Scale (mRS) 0-2 at 3-month follow-up. Additional outcomes included mortality, successful recanalization, defined as mTICI ≥ 2b, stroke severity at discharge, and symptomatic intracerebral hemorrhage (sICH) according to SITS-MOST criteria. Logistic regression was modeled to define independent predictors of the primary outcome.

RESULTS

Overall, 180 consecutive people were enrolled (IVT = 59, EVT = 38, BT = 83), mean age 75. BT emerged as independent predictor of primary outcome (OR = 2.76, 95% CI = 1.08-7.07) together with age (OR = 0.94, 95% CI = 0.9-0.97) and baseline NIHSS (OR = 0.88, 95% CI = 0.81-0.95). BT associated with a 20% relative increase in successful recanalization compared to EVT (74.4 vs 56.4%, p = 0.049). Rates of sICH (1.1%) and procedural complications (vasospasm 4.1%, SAH in 1.7%) were very low, with no difference across groups.

DISCUSSION

BT may carry a higher chance of good functional outcome compared to EVT/IVT only in people with AIS due to MeVO, with marginally higher rates of successful recanalization. Randomized trials are needed to define optimal treatment tailoring for MeVO.

Safety and efficacy of endovascular thrombectomy for primary and secondary MeVO

BACKGROUND

Medium-vessel occlusions (MeVO) are emerging as a new target for endovascular treatment (EVT). Primary MeVO occur de novo, while secondary MeVO arise from large vessel occlusion (LVO) through clot migration or fragmentation - spontaneously, following intravenous thrombolysis or EVT. We aimed to evaluate efficacy and safety of EVT in primary and EVT-induced secondary MeVO.

METHODS

Retrospective single-center study on consecutive EVT-treated acute ischemic stroke, from 2019-to-2021. We considered: (1) exclusive-LVO, patients with LVO and - in case of residual distal occlusion - no rescue endovascular procedure; (2) primary MeVO: initial A2, A3, M2 non-dominant, M3, P2, P3 occlusions; (3) EVT-induced secondary MeVO, presenting LVO with subsequent (treated) EVT-induced MeVO. We compared (univariable/multivariable logistic regression) EVT efficacy (eTICI≥2b, 3-month modified Rankin Scale [mRS] 0-2) and safety (EVT-complications [vessel dissection, perforation, persistent-SAH], symptomatic ICH) in all MeVO versus exclusive-LVO, primary MeVO versus exclusive-LVO, EVT-induced secondary MeVO versus exclusive-LVO and EVT-induced secondary MeVO versus primary MeVO.

RESULTS

We included 335 patients: 221 (66.0 %) exclusive-LVO and 114 (34.0 %) MeVO (55 [48.2 %] primary, 59 [51.8 %] secondary). Compared to exclusive-LVO, primary MeVO had higher rates of EVT complications (aOR 3.77 [95%CI 1.58-9.00],p=0.003), lower rates of eTICI≥2b (aOR 0.32 [95%CI 0.12-0.88],p=0.027) and mRS 0-2 (aOR 0.28 [95%CI 0.13-0.63],p=0.002). EVT-induced secondary MeVO had no major differences in efficacy and safety outcomes compared to exclusive-LVO, but a better mRS 0-2 (aOR 8.00 [95%CI 2.12-30.17],p=0.002) compared to primary MeVO.

CONCLUSIONS

Primary and EVT-induced secondary MeVO showed different safety/efficacy EVT-related profiles. Dedicated randomized data are needed to identify the best acute reperfusion strategy in the two categories.

Multicenter investigation of technical and clinical outcomes after thrombectomy for distal vessel occlusion by frontline technique

BACKGROUND

Endovascular thrombectomy (EVT) is the standard-of-care for proximal large vessel occlusion (LVO) stroke. Data on technical and clinical outcomes in distal vessel occlusions (DVOs) remain limited.

METHODS

This was a retrospective study of patients undergoing EVT for stroke at 32 international centers. Patients were divided into LVOs (internal carotid artery/M1/vertebrobasilar), medium vessel occlusions (M2/A1/P1) and isolated DVOs (M3/M4/A2/A3/P2/P3) and categorized by thrombectomy technique. Primary outcome was a good functional outcome (modified Rankin Scale ≤2) at 90 days. Secondary outcomes included recanalization, procedure-time, thrombectomy attempts, hemorrhage, and mortality. Multivariate logistic regressions were used to evaluate the impact of technical variables. Propensity score matching was used to compare outcome in patients with DVO treated with aspiration versus stent retriever RESULTS: We included 7477 patients including 213 DVOs. Distal location did not independently predict good functional outcome at 90 days compared with proximal (p=0.467). In distal occlusions, successful recanalization was an independent predictor of good outcome (adjusted odds ratio (aOR) 5.11, p<0.05) irrespective of technique. Younger age, bridging therapy, and lower admission National Institutes of Health Stroke Scale (NIHSS) were also predictors of good outcome. Procedure time ≤1 hour or ≤3 thrombectomy attempts were independent predictors of good outcomes in DVOs irrespective of technique (aOR 4.5 and 2.3, respectively, p<0.05). There were no differences in outcomes in a DVO matched cohort of aspiration versus stent retriever. Rates of hemorrhage and good outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group and attempts in the stent retriever group.

CONCLUSIONS

Outcomes following EVT for DVO are comparable to LVO with similar results between techniques. Techniques may exhibit different futility metrics; stent retriever thrombectomy was influenced by attempts whereas aspiration was more dependent on procedure time.

A review of acute ischemic stroke caused by distal, medium vessel occlusions

Acute ischemic stroke (AIS) due to distal, medium vessel occlusion (DMVO) is increasingly recognized as the next frontier for mechanical thrombectomy. Distal, medium vessel occlusions are typically defined as an occlusion in the following arteries: anterior cerebral artery, M2-M4 segments of the middle cerebral artery, posterior cerebral artery, posterior inferior cerebellar artery, anterior inferior cerebellar artery, and superior cerebellar artery. It is estimated that 25-40% of all AIS is due to DMVO. Because of the large burden of DMVO, the frequency of literature published regarding these occlusions has greatly increased in recent years. Furthermore, treatment modalities have been created specifically for DMVOs. Due to the rapidly evolving literature on this topic, remaining up to date on DMVO definitions, anatomy, management, imaging, and clinical course is difficult. In this review article, we synthesized existing literature regarding the aforementioned topics and discussed future directions.

Aspiration Versus Stent‐Retriever as First‐Line Endovascular Therapy Technique for Primary Medium and Distal Intracranial Occlusions: A Propensity‐Score Matched Multicenter Analysis

BACKGROUND

For acute proximal intracranial artery occlusions, contact aspiration may be more effective than stent‐retriever for first‐line reperfusion therapy. Due to the lack of data regarding medium vessel occlusion thrombectomy, we evaluated outcomes according to first‐line technique in a large, multicenter registry.

METHODS

Imaging, procedural, and clinical outcomes of patients with acute proximal medium vessel occlusions (M2, A1, or P1) or distal medium vessel occlusions (M3, A2, P2, or further) treated at 37 sites in 10 countries were analyzed according to first‐line endovascular technique (stent‐retriever versus aspiration). Multivariable logistic regression and propensity‐score matching were used to estimate the odds of the primary outcome, expanded Thrombolysis in Cerebral Infarction score of 2b–3 (“successful recanalization”), as well as secondary outcomes (first‐pass effect, expanded Thrombolysis in Cerebral Infarction 2c‐3, intracerebral hemorrhage, and 90‐day modified Rankin scale, 90‐day mortality) between treatment groups.

RESULTS

Of the 440 included patients (44.5% stent‐retriever versus 55.5% aspiration), those treated with stent‐retriever had lower baseline Alberta Stroke Program Early Computed Tomography Scale scores (median 8 versus 9; P <0.01), higher National Institutes of Health Stroke Scale scores (median 13 versus 11; P =0.02), and nonsignificantly fewer medium‐distal occlusions (M3, A2, P2, or other: 17.4% versus 23.8%; P =0.10). Use of a stent‐retriever was associated with 15% lower odds of successful recanalization (odds ratio [OR], 0.85; [95% CI 0.74–0.98]; P =0.02), but this was not significant after multivariable adjustment in the total cohort (adjusted OR, 0.88; [95% CI 0.72–1.09]; P =0.24), or in the propensity‐score matched cohort (n=105 in each group) (adjusted OR, 0.94; [95% CI 0.75–1.18]; P =0.60). There was no significant association between technique and secondary outcomes in the propensity‐score matched adjusted models.

CONCLUSION

In this large, diverse, multinational medium vessel occlusion cohort, we found no significant difference in imaging or clinical outcomes with aspiration versus stent‐retriever thrombectomy.

Feasibility and safety of ADAPT in acute distal posterior cerebral artery occlusions

PURPOSE

The direct aspiration first pass technique (ADAPT) is an effective and safe endovascular treatment for distal medium vessel occlusions (DMVO) of the anterior circulation. Clinical experience with ADAPT in the distal posterior circulation, however, is still limited and published data is scarce. In this original work, feasibility, safety and efficacy of ADAPT with distal access catheters (DAC) for treatment of acute distal posterior cerebral artery occlusions (DPCAOs) is evaluated.

METHOD

All acute ischemic stroke patients between 2017 and 2022 with primary or secondary DPCAOs in the P2 or P3 segment, that underwent thrombectomy of the DPACO using ADAPT with DACs as frontline therapy, were identified. Demographic data, recanalization rates, procedural safety, and clinical outcome were assessed.

RESULTS

Twenty-four patients with primary (n = 6) or secondary (n = 18) DPCAOs (P2: 21/24; P3: 3/24) were included. Median NIHSS score at admission was 14.5 (IQR 9.5). In all cases, the DPCAO could be reached with the DAC. Successful revascularization (DMVO-p-TICI ≥ 2b) with ADAPT was achieved in 79.2% (19/24), including a first pass effect of 62.5% (15/24), leading to complete recanalization (DMVO-p-TICI 3). Median number of passes was 1 (range 1-2). No complications related to distal PCA aspiration thrombectomy occurred. Median NIHSS and mRS scores at discharge were 4 (IQR 8) and 3 (IQR 2), respectively.

CONCLUSIONS

ADAPT appears to be feasible, safe and effective for the treatment of acute DPCAOs in the setting of different occlusion patterns. High revascularization rates without procedural complications can be achieved. Further studies are needed to consolidate these results.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Strengthening the Description of Superior Mesenteric Artery Occlusions in Acute Mesenteric Ischaemia: Proposition for an Anatomical Classification

OBJECTIVE

The aim of this study was to propose computed tomography angiography (CTA) based anatomical segmentation of the superior mesenteric artery (SMA), in order to standardise the reporting of occlusive lesions in acute mesenteric ischaemia (AMI).

METHODS

A retrospective CTA evaluation of patients with occlusive AMI admitted between 2016 and 2021. After the screening of 468 patients, 95 were included. The SMA was segmented into proximal (S1, ostium to the inferior pancreaticoduodenal artery), middle (S2, from the inferior pancreaticoduodenal to the ileocolic artery), and distal (S3, downstream the ileocolic artery) sections. The jejunal arteries were labelled J1 to J6, and the middle, right, and ileocolic arteries C1, C2, and C3. Two radiologists independently applied the proposed segmentation to a cohort of patients with occlusive AMI to describe occlusive lesions. Intra- and inter-rater agreement was assessed with kappa statistics.

RESULTS

Occlusions involved one segment in 50 (53%) patients (S1, n = 27 [28%]; S2, n = 12 [13%]; S3, n = 11 [12%]); two segments in 37 (39%) patients (S2/S3, n = 31 [33%]; S1/S2, n = 3 [3%]; S1/S3, n = 3 [3%]); and all three segments in eight patients (S1/S2/S3, 8%). The median number of jejunal arteries was four (interquartile range 3, 4.5). C1 and C2 were present in 93 (98%) and 23 patients (24%), respectively. Almost perfect intra-rater agreement was obtained for S1 (91% agreement, κ = 0.82, 95% confidence interval [CI] 0.72 - 0.92); substantial agreement was obtained for S2 (90% agreement, κ = 0.80, 95% CI 0.68 - 0.92) and S3 (86% agreement, κ = 0.72, 95% CI 0.58 - 0.86). Almost perfect inter-rater agreement (with the second junior reading) was obtained for S1 (97% agreement, κ = 0.95, 95% CI 0.89 - 1.0), S2 (91% agreement, κ = 0.82, 95% CI 0.72 - 0.92), and S3 (agreement 96%, κ = 0.91, 95% CI 0.83 - 0.99).

CONCLUSION

A standardised CTA based anatomical segmental description of SMA occlusive lesions in AMI is proposed; it provided substantial to almost perfect intra- and inter-rater agreement for most anatomical segments.

Aspiration thrombectomy of M2 middle cerebral artery occlusion to treat acute ischemic stroke: A core lab–adjudicated subset analysis from the COMPLETE registry and literature review

Background

Although the benefits of aspiration thrombectomy for treating acute ischemic stroke caused by proximal large vessel occlusion have been established, fewer data are available for evaluating aspiration thrombectomy of distal occlusion. The objective of this study was to evaluate, by means of prospectively collected data, the safety and efficacy of aspiration thrombectomy in patients with M2 middle cerebral artery (MCA) occlusion.

Methods

This study is a subset analysis of a global prospective multicenter observational registry that included patients who presented with either anterior or posterior large vessel occlusion and were eligible for mechanical thrombectomy using the Penumbra System including the Penumbra 3D Revascularization Device. For this analysis, all patients in the registry with M2 MCA occlusion were included.

Results

Of the 650 patients in the registry, 113 (17.4%) had M2 MCA occlusion. The rate of a modified treatment in cerebral infarction score of 2b to 3 after the procedure was 79.6% (90/113), the rate of a modified Rankin Scale score of 0–2 at 90 days was 72.5% (79/109), and the all-cause mortality rate at 90 days was 8.8% (10/113). Device-related serious adverse events occurred in one patient (0.9%) within 24 h and in two patients (1.8%) overall. Procedure-related serious adverse events occurred in four patients (3.5%) within 24 h and in six patients (5.3%) overall (nine events).

Conclusion

For appropriately selected patients, aspiration thrombectomy for acute ischemic stroke due to M2 MCA occlusion was safe and effective, with high rates of technical success and good functional outcome.

Comparing Tigertriever 13 to other thrombectomy devices for distal medium vessel occlusion: A systematic review and meta-analysis

BACKGROUND

There is limited evidence on the optimal endovascular strategy for treatment of distal medium-vessel occlusions (DMVO). The low-profile Tigertriever 13 stent-triever shows early promise as an adaptable device that can navigate the distal vasculature without increasing complication risk in DMVO.

METHODS

Using Nested Knowledge, we screened literature for RCTs and cohort studies on the endovascular treatment of DMVO. The primary outcome was reperfusion success, as measured by thrombolysis in cerebral infarction (TICI) ≥ 2b and secondary outcomes included rate of symptomatic intracranial hemorrhage (sICH), mortality at 90 days, and modified Rankin scale (mRS) scores 0-2 at 90 days. A random-effects model was used to compute pooled prevalence rates and their corresponding 95% confidence intervals (CI).

RESULTS

Eleven studies with 1402 patients, 167 patients treated by Tigertriever 13 and 1235 patients treated by other devices, were included in the meta-analysis. The rate of reperfusion success was similar in patients treated by Tigertriever 13 (83.2% [95% CI: 71.5-96.7%]) versus other devices (81.6% [95% CI: 75.3-88.4%], p > 0.05). The rate of sICH was also similar in patients treated by Tigertriever 13 (7.2% [95% CI: 4.1-12.5%]) versus other devices (6.9% [95% CI: 5.5-8.8%]). There was significant heterogeneity in the reporting of mortality and mRS.

CONCLUSIONS

Tigertriever 13 had similar rates of reperfusion success and sICH as other devices used for the treatment of DMVO. Heterogeneity in data element reporting prevented further analyses. Further studies evaluating Tigertriever 13 and other potential devices in DMVO should attempt to harmonize data element reporting.

Stent Retriever or Aspiration Catheter Alone vs Their Combination as the First-Line Thrombectomy in Acute Stroke

BACKGROUND

The single-device simplicity for mechanical thrombectomy (MT) is now challenged by the complementary efficacy of dual-device first-line with a stent retriever and an aspiration catheter.

OBJECTIVE

To compare the outcomes after MT initiated with a single device vs dual devices in acute anterior circulation large vessel occlusion.

METHODS

Patients who underwent MT for acute internal carotid artery (ICA) or M1 occlusion between 2015 and 2020 were retrospectively analyzed. We divided patients into 2 groups: single-device first-line, defined as patients who underwent first-device pass with either a stent retriever or aspiration catheter, and dual-device first-line, defined as first-device pass with both devices.

RESULTS

One hundred forty-one patients were in the single-device group, and 119 were in the dual-device group. In the dual-device group, coiling or kinking of the extracranial ICA was more frequent ( P = .07) and the guide catheters were less frequently navigated to the ICA ( P < .001). 37% of the single-device group was converted to dual-device use. The proportions of mTICI ≥ 2c after the first pass were similar (33% vs 32%. adjusted odds ratio 0.91, 95% CI 0.51-1.62). An mRS score of 0 to 2 at 3 months was achieved similarly (53% vs 48%, P = .46). The total cost for thrombectomy devices was lower in the single-device group ( P < .001).

CONCLUSION

The proportions of first-pass mTICI ≥ 2c were not different between the 2 groups with similar functional outcomes, although the dual-device group more likely to have unfavorable vascular conditions.

Multicenter investigation of technical and clinical outcomes after thrombectomy for Proximal Medium Vessel Occlusion (pMeVO) by frontline technique

BACKGROUND

Endovascular thrombectomy(EVT) is the standard of care for large vessel occlusion(LVO) stroke. Data on technical and clinical outcome in proximal medium vessel occlusions(pMeVOs) comparing frontline techniques remain limited.

METHODS

We report an international multicenter retrospective study of patients undergoing EVT for stroke at 32 centers between 2015-2021. Patients were divided into LVOs(ICA/M1/Vertebrobasilar) or pMeVOs(M2/A1/P1) and categorized by thrombectomy technique. Primary outcome was 90-day good functional outcome(mRS ≤ 2). Multivariate logistic regressions were used to evaluate the impact of technical variables on clinical outcomes. Propensity score matching was used to compare outcome in patients with pMeVO treated with aspiration versus stent-retriever.

RESULTS

In the cohort of 5977 LVO and 1287 pMeVO patients, pMeVO did not independently predict good-outcome(p  =  0.55). In pMeVO patients, successful recanalization irrespective of frontline technique(aOR = 3.2,p < 0.05), procedure time ≤ 1-h(aOR = 2.2,p < 0.05), and thrombectomy attempts ≤ 4(aOR =  2.8,p < 0.05) were independent predictors of good-outcomes.In a propensity-matched cohort of aspiration versus stent-retriever pMeVO patients, there was no difference in good-outcomes. The rates of hemorrhage were higher(9%vs.4%,p < 0.01) and procedure time longer(51-min vs. 33-min,p < 0.01) with stent-retriever, while the number of attempts was higher with aspiration(2.5vs.2,p < 0.01). Rates of hemorrhage and good-outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group compared to attempts in the stent-retriever group.

CONCLUSIONS

Clinical outcomes following EVT for pMeVO are comparable to those in LVOs. The golden hour or 3-pass rules in LVO thrombectomy still apply to pMeVO thrombectomy. Different techniques may exhibit different futility metrics; SR thrombectomy was more influenced by attempts whereas aspiration was more dependent on procedure time.

First-line thrombectomy strategy for distal and medium vessel occlusions: a systematic review

BACKGROUND

The benefit of mechanical thrombectomy (MT) and efficacy of different first-line MT techniques remain unclear for distal and medium vessel occlusions (DMVOs). In this systematic review, we aimed to compare the performance of three first-line MT techniques in DMVOs.

METHODS

The PubMed database was searched for studies examining the utility of MT in DMVOs (middle cerebral artery M2-3-4, anterior cerebral artery, and posterior cerebral artery). Studies providing data for aspiration thrombectomy (ASP), stent retriever thrombectomy (SR), and combined SR+ASP technique were included. Non-comparative studies were excluded. Safety and efficacy data were collected for each technique. The Nested Knowledge AutoLit platform was utilized for literature search, screening, and data extraction. Pooled data were presented as descriptive statistics.

RESULTS

13 studies comprising 2422 MT procedures were identified. The overall successful recanalization rate was 77.0% (1513/1964) for DMVOs. SR+ASP had a successful recanalization rate of 83.7% (297/355), SR had a 75.6% rate (638/844), while ASP alone had a 74.2% rate (386/520). The overall functional independence rate was 51.3% (851/1659) among DMVOs. The ASP alone group had a functional independence rate of 46.9% (219/467), while functional independence rates of the SR and SR+ASP groups were 51.5% (372/723) and 61.7% (174/282), respectively. Finally, the subarachnoid hemorrhage rates were 1.8% (4/217) for the ASP group, 9.3% (26/281) for the SR group, and 11.9% (41/344) for the SR+ASP group.

CONCLUSIONS

Our systematic review supports the proposition that MT is a safe and effective treatment option for DMVOs. Additionally, while the SR+ASP group had consistently high rates of clot clearance and good neurological outcomes, the SR and SR+ASP groups also had higher rates of subarachnoid hemorrhage, highlighting the need for improved DMVO treatment devices.

Endovascular treatment for acute ischaemic stroke due to medium vessel occlusion: data from ANGEL-ACT registry

OBJECTIVES

To investigate the safety and efficacy of endovascular treatment (EVT) for acute medium vessel occlusion (MeVO) in the anterior circulation and to explore the independent predictors of the 90-day good outcome for such patients.

METHODS

Data from ANGEL-ACT Registry were analysed in our study. The outcomes, such as the modified Rankin Scale (mRS) at 90 days, successful recanalisation rate and symptomatic intracranial haemorrhage (SICH) rate, were compared between MeVO and acute large vessel occlusions (LVO). Then, the independent predictors of the good outcome at 90 days in MeVO patients were determined by the logistic regression analyses.

RESULTS

We included 1032 subjects in the analysis, of which, 147 were MeVO and 885 were LVO. mRS at 90 days distribution (3 (0-4) vs 3 (0-5), common odds ratio (OR) =1.00, 95% confidence interval (CI) 0.73 to 1.38, p=0.994), SICH rate (4.8% vs 8.9%; OR=0.59, 95% CI 0.26 to 1.34, p=0.205) and successful recanalisation rate (89.8% vs 89.7%; OR=1.00 95% CI 0.51 to 1.93, p=0.992) were similar between the MeVO and LVO groups after adjusting for the confounders. We identified that baseline neutrophil-to-lymphocyte ratio ≤4.1 (OR=2.13, 95% CI 1.14 to 3.99, p=0.019), baseline National Institutes of Health Stroke Scale ≤14 (OR=1.96, 95% CI 1.02 to 3.80, p=0.045) and mechanical thrombectomy passes ≤1 (OR=2.16, 95% CI 1.14 to 4.11, p=0.021) were independent predictors of the 90-day good outcome in MeVO patients undergoing EVT.

CONCLUSIONS

Patients with MeVO achieved similar 90-day mRS, SICH rate and successful recanalisation rate after EVT compared with patients with LVO. Several independent predictors of 90-day good outcome in MeVO patients undergoing EVT were determined, which should be highly considered in MeVO stroke management.

First-line contact aspiration versus first-line stent retriever for acute ischemic stroke with M2 occlusion: A systematic review and meta-analysis

OBJECTIVE

Mechanical thrombectomy is widely used for acute ischemic stroke caused by middle cerebral artery M2 segment occlusion. However, the comparison between contact aspiration (CA) and stent retriever (SR) used as first-line techniques for acute M2 occlusion is still unclear. We aimed to perform a systematic review and meta-analysis on this issue.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement was followed. Three databases (Pubmed, Embase, and Cochrane) were searched. The Newcastle-Ottawa scale was used to assess the risk of bias for the included studies. We focused on two main outcomes, the final successful reperfusion (modified Thrombolysis in Cerebral Infarction mTICI 2b/3) and 90-day functional independence (modified Rankin Scale score 0-2). The meta-analyses were performed using the random-effects models.

RESULTS

Seven observational studies were included for systematic review. Only one study indicated a superiority of first-line SR in achieving final successful reperfusion, while the other six studies did not show significant difference between these two techniques. And all the seven studies showed comparable proportion of 90-day functional independence. Five studies were available for meta-analysis with 601 patients (239 received first-line CA, 362 received first-line SR). The pooled results also suggested that the proportion of final successful reperfusion (OR=1.18, 95%CI 0.72-1.93, I2 =0%) and 90-day functional independence (OR=1.18, 95%CI 0.82-1.68, I2 =0%) were comparable between these two strategies.

CONCLUSION

For patients with acute M2 occlusion, first-line CA and SR techniques could achieve similar final reperfusion outcomes and 90-day clinical prognosis. Further studies with randomized controlled design are needed.

Aspiration Versus Stent Retriever Thrombectomy for Distal, Medium Vessel Occlusion Stroke in the Posterior Circulation: A Subanalysis of the TOPMOST Study

BACKGROUND

The optimal endovascular strategy for reperfusing distal medium-vessel occlusions (DMVO) remains unknown. This study evaluates angiographic and clinical outcomes of thrombectomy strategies in DMVO stroke of the posterior circulation.

METHODS

TOPMOST (Treatment for Primary Medium Vessel Occlusion Stroke) is an international, retrospective, multicenter, observational registry of patients treated for DMVO between January 2014 and June 2020. This study analyzed endovascularly treated isolated primary DMVO of the posterior cerebral artery in the P2 and P3 segment. Technical feasibility was evaluated with the first-pass effect defined as a modified Thrombolysis in Cerebral Infarction Scale score of 3. Rates of early neurological improvement and functional modified Rankin Scale scores at 90 days were compared. Safety was assessed by the occurrence of symptomatic intracranial hemorrhage and intervention-related serious adverse events.

RESULTS

A total of 141 patients met the inclusion criteria and were treated endovascularly for primary isolated DMVO in the P2 (84.4%, 119) or P3 segment (15.6%, 22) of the posterior cerebral artery. The median age was 75 (IQR, 62-81), and 45.4% (64) were female. The initial reperfusion strategy was aspiration only in 29% (41) and stent retriever in 71% (100), both achieving similar first-pass effect rates of 53.7% (22) and 44% (44; P=0.297), respectively. There were no significant differences in early neurological improvement (aspiration: 64.7% versus stent retriever: 52.2%; P=0.933) and modified Rankin Scale rates (modified Rankin Scale score 0-1, aspiration: 60.5% versus stent retriever 68.6%; P=0.4). In multivariable logistic regression analysis, the time from groin puncture to recanalization was associated with the first-pass effect (adjusted odds ratio, 0.97 [95% CI, 0.95-0.99]; P<0.001) that in turn was associated with early neurological improvement (aOR, 3.27 [95% CI, 1.16-9.21]; P<0.025). Symptomatic intracranial hemorrhage occurred in 2.8% (4) of all cases.

CONCLUSIONS

Both first-pass aspiration and stent retriever thrombectomy for primary isolated posterior circulation DMVO seem to be safe and technically feasible leading to similar favorable rates of angiographic and clinical outcome.

Dose-Response Relationship and Threshold Drug Dosage Identification for a Novel Hybrid Mechanical-Thrombolytic System with an Ultra-Low Dose Patch

Introduction

Ischemic stroke treatment has advanced in the last two decades and intravenous thrombolysis is now considered the standard of care for selected patients. Recanalization can also be achieved by mechanical endovascular treatment for patients with large vessel occlusions. Complicating treatment-related symptomatic intracerebral hemorrhage and prolonged needle-to-recanalization times have been identified as major determinants of poor three-month functional outcomes. A hybrid mechanical-thrombolytic system with a patch imbued with an ultra-low dose of thrombolytic agents loaded onto a stent-retriever has been developed.

Methods

In this study, the in situ dose-response relationship of the thrombolytic patch imbued with up to 1000 IU of urokinase plasminogen activator (uPA) was quantified using Raman spectroscopy.

Results

Thrombi of up to 400 μm thickness dissolved within 15 min when patches imbued with < 1% of the conventional thrombolysis therapy dosage were applied. The results demonstrated that low-dose thrombolytic patches can dissolve normal clots compressed in the blood vessel in a short time. 500 IU is the threshold uPA dosage in the thrombolytic patch that most effectively dissolves the clots.

Conclusion

This study suggests that a novel endovascular stent-retriever loaded with an ultra-low drug dose fibrinolytic patch may be a suitable treatment for patients who are ineligible for conventional thrombolytic therapy.

Thrombus Histology as It Relates to Mechanical Thrombectomy: A Meta-Analysis and Systematic Review

BACKGROUND

Appropriate thrombus-device interaction is critical for recanalization. Histology can serve as a proxy for mechanical properties, and thus inform technique selection.

OBJECTIVE

To investigate the value of histologic characterization, we conducted a systematic review and meta-analysis on the relationship between thrombus histology and recanalization, technique, etiology, procedural efficiency, and imaging findings.

METHODS

In this meta-analysis, we identified studies published between March 2010 and March 2020 reporting findings related to the histologic composition of thrombi in large vessel occlusion stroke. Studies with at least 10 patients who underwent mechanical thrombectomy using stent retriever or aspiration were considered. Only studies in which retrieved thrombi were histologically processed were included. Patient-level data were requested when data could not be directly extracted. The primary outcome assessed was the relationship between thrombus histology and angiographic outcome.

RESULTS

A total of 22 studies encompassing 1623 patients met inclusion criteria. Clots associated with good angiographic outcome had higher red blood cell (RBC) content (mean difference [MD] 9.60%, 95% CI 3.85-15.34, P = .008). Thrombi retrieved by aspiration had less fibrin (MD -11.39, 95% CI -22.50 to -0.27, P = .046) than stent-retrieved thrombi. Fibrin/platelet-rich clots were associated with longer procedure times (MD 13.20, 95% CI 1.30-25.10, P = .037). Hyperdense artery sign was associated with higher RBC content (MD 14.17%, 95% CI 3.07-25.27, P = .027). No relationship was found between composition and etiology.

CONCLUSION

RBC-rich thrombi were associated with better recanalization outcomes and shorter procedure times, suggesting that preinterventional compositional characterization may yield important prognostic and therapeutic guidance.

Stent-retriever alone versus combined use of stent-retriever and contact aspiration technique for middle cerebral artery M2 occlusions: a propensity score analysis

BACKGROUND

The optimal endovascular treatment (EVT) technique for middle cerebral artery (MCA) M2 segment occlusions remains unknown. We aim to analyze whether reperfusion rate, procedure times, procedure-related complications, and clinical outcome differed between patients with isolated M2 occlusions who underwent stent-retriever (SR) alone versus combined SR and contact aspiration (CA) as a front-line EVT.

METHODS

Patients who underwent EVT for isolated MCA-M2 occlusion were recruited from the prospectively ongoing ROSSETTI registry. Patients were divided regarding the EVT approach into SR alone versus SR+CA and propensity score matching was used to achieve baseline balance. Demographic, procedural, safety, and clinical outcomes were compared between groups. Multivariable logistic regression analysis was performed to identify independent predictors of first-pass effect (FPE) and 90-day modified Rankin scale (mRS) 0-2.

RESULTS

214 patients underwent EVT for M2 occlusion, 125 treated with SR alone and 89 with SR+CA. Propensity score matchnig analysis selected 134 matched patients. The rates of FPE (42% vs 40%, p=1.000) and 90-day mRS 0-2 (60% vs 51%, p=0.281) were comparable between groups. Patients treated with SR alone had lower need of rescue therapy (p=0.006), faster times to reperfusion (p<0.001), and lower procedure-related complications (p=0.031). Higher initial Alberta Stroke Program Early CT Score was an independent predictor of FPE. Age, baseline National Institutes of Health Stroke Scale score, and procedure duration were significant predictors of good clinical outcome at 3 months.

CONCLUSIONS

As front-line modality in M2 occlusions, the SR alone approach results in similar rates of reperfusion and good clinical outcomes to combined SR+CA and might be advantageous due to faster reperfusion times and fewer adverse events.

Mechanical thrombectomy for acute ischemic stroke with occlusion of the M2 segment of the middle cerebral artery: A literature review

Thanks to new generation devices, mechanical thrombectomy (MT) has substantially evolved and become the standard treatment for patients with acute occlusion of the internal carotid artery or proximal middle cerebral artery (MCA) (M1 segment). However, the role and benefit of MT in patients with distal MCA (M2 segment) occlusion remain unclear. Therefore, there is a need for further studies. To evaluate the efficacy and safety of MT for M2 occlusion, this article reviews the natural course of M2 occlusion, the evidence regarding MT for M2 segment occlusion, clinical outcomes of MT for M2 occlusion, and treatment outcomes according to device type.

Middle Cerebral Artery M2 Thrombectomy in the STRATIS Registry

BACKGROUND AND PURPOSE

The safety and benefit of mechanical thrombectomy in the treatment of acute ischemic stroke patients with M2 segment middle cerebral artery occlusions remain uncertain. Here, we compare clinical and angiographic outcomes in M2 versus M1 occlusions in the STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) Registry.

METHODS

The STRATIS Registry was a prospective, multicenter, nonrandomized, observational study of acute ischemic stroke large vessel occlusion patients treated with the Solitaire stent-retriever as the first-choice therapy within 8 hours from symptoms onset. Primary outcome was defined as functional disability at 3 months measured by dichotomized modified Rankin Scale. Secondary outcomes included reperfusion rates and rates of symptomatic intracranial hemorrhage.

RESULTS

A total of 984 patients were included, of which 538 (54.7%) had M1 and 170 (17.3%) had M2 occlusions. Baseline demographics were well balanced within the groups, with the exception of mean baseline National Institutes of Health Stroke Scale score which was significantly higher in the M1 population (17.3±5.5 versus 15.7±5.0, P≤0.001). No difference was seen in mean puncture to revascularization times between the cohorts (46.0±27.8 versus 45.1±29.5 minutes, P=0.75). Rates of successful reperfusion (modified Thrombolysis in Cerebral Infarction≥2b) were similar between the groups (91% versus 95%, P=0.09). M2 patients had significantly increased rates of symptomatic ICH at 24 hours (4% versus 1%, P=0.01). Rates of good functional outcome (modified Rankin Scale score of 0-2; 58% versus 59%, P=0.83) and mortality (15% versus 14%, P=0.75) were similar between the 2 groups. There was no difference in the association of outcome and onset to groin puncture or onset to successful reperfusion in M1 and M2 occlusions.

CONCLUSIONS

In the STRATIS Registry, M2 occlusions achieved similar rates of successful reperfusion, good functional outcome, and mortality, although increased rates of symptomatic ICH were demonstrated when compared with M1 occlusions. The time dependence of benefit was also similar between the 2 groups. Further studies are needed to understand the benefit of mechanical thrombectomy for M2 occlusions.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239640.

Stroke thrombectomy complication management

Endovascular mechanical thrombectomy (EVT) is widely accepted as the first-line treatment for acute ischemic stroke in patients with large vessel occlusion. Being an invasive treatment, this method is associated with various preoperative, perioperative, and postoperative complications. These complications may influence peri-interventional morbidity and mortality and therefore treatment efficacy and clinical outcome. The aim of this review is to discuss the most common types of complications associated with EVT, the probable mechanisms of injury, and effective methods to manage and prevent complications.

Endovascular reperfusion of M2 occlusions in acute ischemic stroke reduced disability and mortality: ETIS Registry results

BACKGROUND

The predictors of successful reperfusion and the effect of reperfusion after endovascular treatment (EVT) for M2 occlusions have not been well studied. We aimed to identify predictors of successful reperfusion and the effect of reperfusion on outcomes of EVT for M2 occlusions in current practice.

METHODS

Patients with acute ischemic stroke due to isolated M2 occlusions who were enrolled in the prospective multicenter Endovascular Treatment in Ischemic Stroke (ETIS) Registry in France between January 2015 and March 2020 were included. The primary outcome was a favorable outcome, defined as modified Rankin Scale (mRS) score of 0-2 at 90 days. Successful reperfusion was defined as an improvement of ≥1 points in the modified Thrombolysis In Cerebral Infarction score between the first and the last intracranial angiogram.

RESULTS

A total of 458 patients were included (median National Institutes of Health Stroke Scale (NIHSS) score 14; 61.4% received prior intravenous thrombolysis). Compared with the non-reperfused patients, reperfused patients had an increased rate of excellent outcome (OR 2.3, 95% CI 0.98 to 5.36; p=0.053), favorable outcome (OR 2.79, 95% CI 1.31 to 5.93; p=0.007), and reduced 90-day mortality (OR 0.39, 95% CI 0.19 to 0.79; p<0.01). Admission NIHSS score was the only predictor of successful reperfusion. First-line strategy was not a predictor of successful reperfusion or favorable outcome, but the use of a stent retriever, alone or with an aspiration catheter, was associated with higher rates of procedural complications and 90-day mortality.

CONCLUSIONS

Successful reperfusion of M2 occlusions reduced disability and mortality. However, safety is a concern, especially if the procedure failed.

Subarachnoid Hemorrhage in Mechanical Thrombectomy for Acute Ischemic Stroke: Analysis of the STRATIS Registry, Systematic Review, and Meta-Analysis

Background: The indications for mechanical thrombectomy in acute ischemic stroke continue to broaden, leading neurointerventionalists to treat vessel occlusions at increasingly distal locations farther in time from stroke onset. Accessing these smaller vessels raises the concern of iatrogenic subarachnoid hemorrhage (SAH) owing to increasing complexity in device navigation and retrieval. This study aims to determine the prevalence of SAH following mechanical thrombectomy, associated predictors, and resulting functional outcomes using a multicenter registry and compare this with a systematic review and meta-analysis of the literature. Methods: Data from STRATIS (The Systematic Evaluation of Patients Treated with Neurothrombectomy Devices for Acute Ischemic Stroke) registry were analyzed dichotomized by the presence or absence of SAH after thrombectomy. Only patients with 24-h post-procedural neuroimaging were included (n = 841). Multivariable logistic regression was performed to identify significant predictors of SAH. A systematic review and random-effects meta-analysis was also conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) protocol. Results: The prevalence of post-thrombectomy SAH was 5.23% in STRATIS with 15.9% (1.84% overall) experiencing neurological decline. Distal location of vessel occlusion (OR 3.41 [95% CI: 1.75-6.63], p < 0.001) and more than 3 device passes (OR 1.34 [95% CI: 1.09-1.64], p = 0.01) were associated with a higher probability of SAH in contrast to a reduction with administration of intravenous tissue plasminogen activator (tPA) (OR 0.48 [95% CI: 0.26-0.89], p = 0.02). There was a trend toward a higher discharge NIHSS (8.3 ± 8.7 vs. 5.3 ± 6.6, p = 0.07) with a significantly reduced proportion achieving functional independence at 90 days (modified Rankin Score 0-2: 32.5% vs. 57.8%, p = 0.002) in SAH patients. Pooled analysis of 10,126 patients from 6 randomized controlled trials and 64 observational studies demonstrated a prevalence of 5.85% [95% CI: 4.51-7.34%, I ²: 85.2%]. Only location of vessel occlusion was significant for increased odds of SAH at distal sites (OR 2.89 [95% CI: 1.14, 7.35]). Conclusions: Iatrogenic SAH related to mechanical thrombectomy is more common with treatment of distally-situated occlusions and multiple device passes. While low in overall prevalence, its effect is not benign with fewer patients reaching post-procedural functional independence, particularly if symptomatic.

Endovascular Management of Intracranial Atherosclerosis-Related Large Vessel Occlusion With the A Direct Aspiration First-Pass Thrombectomy Compared With Solumbra Technique

Background: To investigate the effect of the A Direct Aspiration First-Pass Thrombectomy (ADAPT) vs. Solumbra technique in the treatment of acute intracranial atherosclerosis-related large vessel occlusion (LVO).

Methods: Patients with acute atherosclerosis-related LVO who had undergone endovascular treatment were retrospectively enrolled into two groups: The Solumbra and ADAPT groups. The clinical data were analyzed.

Results: Patients (104) were enrolled with 48 in the Solumbra and 56 in the ADAPT group. The mean time from femoral access to recanalization was significantly (P < 0.05) shorter in the ADAPT than in the Solumbra group. The recanalization time at the first line was significantly shorter in the ADAPT group than in the Solumbra group (17 ± 10.21 vs. 26 ± 15.55 min, P = 0.02). However, the rate of switching to the alternative was significantly higher in the ADAPT group than that in the Solumbra group (46.42 vs. 33.33%, P = 0.01). Eighty-two patients had eventual recanalization, resulting in a final recanalization rate of 78.85%. At 3-month clinical follow-up for all patients, the good prognosis rate reached 51.92% with good prognosis in 24 patients (50%) in the Solumbra and 30 (53.57%) in the ADAPT group. The rate of symptomatic intracranial hemorrhage was 18.75% (n = 9) in the Solumbra and 19.64% (n = 11) in the ADAPT group. The mortality rate was 21.15% (22/104). Among 80 (76.92%) patients who had angiographic follow-up (3–30 months), five (6.25%) patients experienced in-stent stenosis, and two (2.5%) experienced asymptomatic stent occlusion.

Conclusion: In patients with acute intracranial atherosclerosis-related LVO, clinical outcomes treated using the ADAPT technique are comparable with those using the Solumbra technique, and more patients need additional remedial measures if treated with the ADAPT technique.

A review of endovascular treatment for medium vessel occlusion stroke

Medium-vessel occlusions (MeVOs), that is, occlusions of the M2/3 middle cerebral artery, A2/3 anterior cerebral artery, and P2/3 posterior cerebral artery segments, account for 25%-40% of all acute ischemic stroke cases. Clinical outcomes of MeVO stroke with intravenous thrombolysis, which is the current standard of care, are moderate at best. With improving imaging technologies and a growing literature, MeVOs are increasingly recognized as a target for endovascular treatment (EVT). For the time being, there is limited but promising evidence for the safety and efficacy of MeVO EVT, and many neurointerventionists are already routinely offering EVT for MeVO stroke, despite the lack of clear guideline recommendations. In this article, we review the evidence on endovascular treatment for MeVO stroke and summarize the available literature on current imaging strategies, commonly used EVT selection criteria, EVT techniques, and outcome assessment for MeVO stroke.

Experimental evaluation of direct thromboaspiration efficacy according to the angle of interaction between the aspiration catheter and the clot

Background

Successful direct thromboaspiration (DTA) is related to several factors such as clot consistency, size, and location. It has also been demonstrated recently that the angle of interaction (AOI) formed by the aspiration catheter and the clot is related to DTA efficacy. The aims of this study were three-fold: (a) to confirm the clinical finding that the AOI formed by the aspiration catheter and the clot influence DTA efficacy; (b) to evaluate to what extent this influence varies according to differences in clot consistency and size; and (c) to validate stent retriever thrombectomy as an effective rescue treatment after DTA failure in the presence of an unfavorable AOI.

Methods

A rigid vascular phantom designed to reproduce a middle cerebral artery trifurcation anatomy with three M2 segments forming different angles with M1 and thrombus analog of different consistencies and sizes was used.

Results

DTA was highly effective for AOIs >125.5°, irrespective of thrombus analog features. However, its efficacy decreased for acute AOIs. Rescue stent retriever thrombectomy was effective in 92.6% of cases of DTA failure.

Conclusions

This in vitro study confirmed that the AOI formed by the aspiration catheter and the thrombus analog influenced DTA efficacy, with an AOI >125.5° related to an effective DTA. Stent retriever thrombectomy was an effective rescue treatment after DTA failure, even in the presence of an unfavorable AOI.

Safety and Efficacy of Mechanical Thrombectomy Using Tigertriever as a Rescue Device After Failed Aspiration-Single Center Experience

Introduction: We evaluated the safety and efficacy of a new stent retriever-Tigertriever-after failed aspiration. Materials and Methods: Patients with acute ischemic stroke treated with Tigertriever between January 2018 and March 2020 were included in the study. Treatment results of Tigertriever in rescue therapy (after failed aspiration) were evaluated. Periprocedural data were retrospectively analyzed. Results: Thirty patients were treated with Tigertriever (14M/16F). There were 20 rescue thrombectomies after failed aspiration. Tigertriver successful recanalization rate (mTICI ≥ 2B) was 70%: 65% in rescue therapy and 80% in first-line therapy. The type of first line treatment had no impact on mRS after 1 month and 3 months (ns). There was significant improvement in NIHSS in all patients (mean NIHSS: 17 vs. 10, p = 0.028), in rescue treatment (mean NIHSS: 17 vs. 11, p = 0.048) and in first line treatment (mean NIHSS: 16 vs. 8, p = 0.0005). Better results in NIHSS at discharge were linked with first pass success (p = 0.002), better mTICI at the end of the procedure (p = 0.0006), and administration of rtPA (p = 0.013). Conclusions: The new stent retriever Tigertriever is an efficient and safe tool to be used as a rescue device after an unsuccessful first line aspiration technique.

Similarities and Differences Between Primary Percutaneous Coronary Intervention and Mechanical Thrombectomy

Acute ischemic stroke is among the leading causes of mortality and disability worldwide. Since 2015, as was the case for primary percutaneous coronary intervention for acute myocardial infarction, catheter-based reperfusion via mechanical thrombectomy (MT) has become the gold-standard treatment for acute ischemic stroke caused by large-vessel occlusion. Despite that, only a fraction of the world's population currently would be able to undergo MT in time, mostly because of the scarcity of 24/7 coverage by neurointerventionalists to deal with this enormous burden. Interventional cardiologists have thus been considered a logical option to aid in combating this vast demand to diminish the burden of acute ischemic stroke. However, despite some seemingly evident similarities between primary percutaneous coronary intervention and MT, for interventional cardiologists to enter this new field, they must be well trained and fully aware of all the clinical, technical, and environmental differences between these two scenarios. The main objective of this state-of-the-art paper is to serve as an introductory and comprehensive guide to familiarize the interventional cardiology community with the most critical technical aspects of MT.

Emergent surgical embolectomy for middle cerebral artery occlusion related to cerebral angiography followed by neck clipping for an unruptured aneurysm in the anterior communicating artery

Background:

Intracranial embolism related to cerebral angiography is rare but one of the complications of the procedure. However, the standard management of acute intracranial embolism for this etiology has not been established, and there have been very few reports in the past.

Case Description:

A 68-year-old male was incidentally found to have an unruptured aneurysm of anterior communicating artery (ACoA). Immediately after the cerebral angiography for the purpose of detailed examination of the aneurysm, the right partial hemiparalysis and mild aphasia developed. Magnetic resonance imaging/angiography (MRI/A) revealed an occlusion in the peripheral part of the left middle cerebral artery (MCA). Due to the existence of magnetic resonance angiography-diffusion mismatch, emergent craniotomy was immediately performed to remove intra-arterial thrombus. We also performed clipping for an unruptured ACoA aneurysm with this approach. Postoperative MRI/A showed that the occluded artery was recanalized and a slight infarction was observed in the left cerebral hemisphere. The patient was discharged on foot and followed at outpatient clinic over 4 years without no neurological deficit.

Conclusion:

Emergent surgical embolectomy for distal MCA occlusion related to cerebral angiography followed by neck clipping for an unruptured aneurysm of the ACoA was successful in treating acute occlusion of the peripheral part of the MCA in a patient with an unruptured aneurysm. As there are few similar cases, there is controversy about the best management, but this surgical method can be a safe and effective treatment.

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

BACKGROUND AND PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Benefit of endovascular thrombectomy for M2 middle cerebral artery occlusion in the ARISE II study

Background

The benefit of endovascular thrombectomy for acute ischemic stroke with M2 segment middle cerebral artery occlusion remains controversial, with uncertainty and paucity of data specific to this population.

Objective

To compare outcomes between M1 and M2 occlusions in the Analysis of Revascularization in Ischemic Stroke with EmboTrap (ARISE II) trial.

Methods

We performed a prespecified analysis of the ARISE II trial with the primary outcome of 90-day modified Rankin Scale score of 0–2, which we termed good outcome. Secondary outcomes included reperfusion rates and major adverse events. The primary predictor was M2 occlusion, which we compared with M1 occlusion.

Results

We included 183 patients, of whom 126 (69%) had M1 occlusion and 57 (31%) had M2 occlusion. There was no difference in the reperfusion rates or adverse events between M2 and M1 occlusions. The rate of good outcome was not different in M2 versus M1 occlusions (70.2% vs 69.7%, p=0.946). In a logistic regression model adjusted for age, sex, and baseline National Institutes of Health Stroke Scale score, M2 occlusions did not have a significantly different odds of good outcome compared with M1 occlusions (OR 0.94, 95% CI 0.47 to 1.88, p=0.87).

Conclusion

In ARISE II, M2 occlusions achieved a 70.2% rate of good outcome at 90 days, which is above published rates for untreated M2 occlusions and superior to prior reports of M2 occlusions treated with endovascular thrombectomy. We also report similar rates of good outcome, successful reperfusion, death, and other adverse events when comparing the M1 and M2 occlusions.

Thrombectomy for Distal, Medium Vessel Occlusions: A Consensus Statement on Present Knowledge and Promising Directions

Endovascular thrombectomy (EVT) is well established as a highly effective treatment for acute ischemic stroke (AIS) due to proximal, large vessel occlusions (PLVOs). With iterative further advances in catheter technology, distal, medium vessel occlusions (DMVOs) are now emerging as a promising next potential EVT frontier. This consensus statement integrates recent epidemiological, anatomic, clinical, imaging, and therapeutic research on DMVO-AIS and provides a framework for further studies. DMVOs cause 25% to 40% of AISs, arising as primary thromboemboli and as unintended consequences of EVT performed for PLVOs, including emboli to new territories (ENTs) and emboli to distal territories (EDTs) within the initially compromised arterial field. The 6 distal medium arterial arbors (anterior cerebral artery [ACA], M2–M4 middle cerebral artery [MCA], posterior cerebral artery [PCA], posterior inferior cerebellar artery [PICA], anterior inferior cerebellar artery [AICA], and superior cerebellar artery [SCA]) typically have 25 anatomic segments and give rise to 34 distinct arterial branches nourishing highly differentiated, largely superficial cerebral neuroanatomical regions. DMVOs produce clinical syndromes that are highly heterogenous but frequently disabling. While intravenous fibrinolytics are more effective for distal than proximal occlusions, they fail to recanalize one-half to two-thirds of DMVOs. Early clinical series using recently available, smaller, more navigable stent retriever and thromboaspiration devices suggest EVT for DMVOs is safe, technically efficacious, and potentially clinically beneficial. Collaborative investigations are desirable to enhance imaging recognition of DMVOs; advance device design and technical efficacy; conduct large registry studies using harmonized, common data elements; and complete formal randomized trials, improving treatment of this frequent mechanism of stroke.

Microcatheter infusion of bolus-dose tirofiban for acute ischemic stroke due to distal intracranial artery occlusion

The utility of endovascular thrombectomy for acute occlusion of the distal intracranial artery (A2/A3/M2/M3/P2/P3) is unclear, and aspiration and stent thrombectomy are associated with risk of bleeding. We analyzed patients with acute occlusion of the distal intracranial artery to assess the safety and efficacy of microcatheter-based tirofiban infusion.We retrospectively reviewed data of the endovascular thrombectomy registry of our center between January 2018 and June 2019. Patients with distal intracranial artery occlusion who underwent endovascular thrombectomy with microcatheter-based infusion of tirofiban were recruited.Of 13 patients included, 1 presented with anterior cerebral artery occlusion, 2 with posterior cerebral artery occlusion, 2 with posterior inferior cerebellar artery occlusion, and 7 with middle cerebral artery M2 occlusion. The mean National Institute of Health Stroke scale score was 10.1 (3-19). Three patients (23.1%) underwent bridging treatment of intravenous thrombolysis with recombinant plasminogen activator and endovascular thrombectomy. The arithmetic mean onset-to-recanalization time was 696.3 minutes (140-1440) and average operating time was 47.1 minutes (30-80). After treatment, 10 patients (76.9%) underwent revascularization. No operative complications were observed in any case. All patients underwent angiography and were reviewed 7 to 14 days after surgery. Imaging revealed significant improvements in recanalization compared with the immediate postoperative period, with no reoccurrence of occlusion. The mean modified Rankin scale score at the 3-month follow-up was 0.54 (0-2).Microcatheter-based infusion of bolus-dose tirofiban can result in safe and effective recanalization of acute occlusion of the distal artery in the case of a relatively light thrombotic load.

Clinical considerations and assessment of risk factors when choosing endovascular thrombectomy for acute stroke

INTRODUCTION

The advent of endovascular thrombectomy (EVT) has been a game changer for the management of acute ischemic stroke due to large vessel occlusion. However, the selection of suitable candidates for EVT remains a significant challenge.

AREAS COVERED

This review focuses on the clinical, radiological, and procedural considerations for EVT in acute stroke that assist in optimal patient selection.

EXPERT OPINION

All patients presenting with significant clinical deficits with treatable occlusions, who have salvageable brain tissue at presentation might benefit from treatment up to twenty-four hours from symptom onset. Neuroimaging tools form the backbone for this decision making.

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.

Aspiration thrombectomy as the first-line treatment of M2 occlusions

PURPOSE

The aim of the present study was (i) to evaluate the safety and efficacy of aspiration thrombectomy in patients with M2 occlusions and (ii) to compare outcome of treatment of occlusion of different M2 segments.

MATERIALS AND METHODS

Between March 2016 and June 2019, 82 patients with acute ischemic stroke and isolated M2 occlusions were treated in cerebrovascular stroke center with aspiration thrombectomy as the first-line treatment. Functional outcomes of patients with different types of M2 occlusions were statistically compared. Multivariable logistic regression analysis was performed to determine the factors associated with good clinical outcome.

RESULTS

The mean age was 71.9 ± 13.4 years, 47.6% were men. Aspiration thrombectomy alone was utilized in 72.5% of patients, with 27.5% of patients being treated with a combination of aspiration thrombectomy and stent retriever. At the three-month follow-up, there was no statistically significant difference in functional outcome between different types of M2 occlusions (p = 0.662), however in the underpowered analysis because of the small sample size of patients, with good clinical outcome mRS 0-2 in 50% of all treated patients. Symptomatic intracranial hemorrhage was found in 6.1% of patients. Lower age (OR 0.932, 95% CI 0.878-0.988) and lower NIHSS score upon admission (OR 0.893, 95% CI 0.805-0.991) were independent predictors of good clinical outcome.

CONCLUSION

Aspiration thrombectomy appeared to be a safe and effective first-line treatment option for patients with M2 occlusion, being the first-line option for almost three-quarters of patients.

Management of acute ischemic stroke

Stroke is the leading cause of long term disability in developed countries and one of the top causes of mortality worldwide. The past decade has seen substantial advances in the diagnostic and treatment options available to minimize the impact of acute ischemic stroke. The key first step in stroke care is early identification of patients with stroke and triage to centers capable of delivering the appropriate treatment, as fast as possible. Here, we review the data supporting pre-hospital and emergency stroke care, including use of emergency medical services protocols for identification of patients with stroke, intravenous thrombolysis in acute ischemic stroke including updates to recommended patient eligibility criteria and treatment time windows, and advanced imaging techniques with automated interpretation to identify patients with large areas of brain at risk but without large completed infarcts who are likely to benefit from endovascular thrombectomy in extended time windows from symptom onset. We also review protocols for management of patient physiologic parameters to minimize infarct volumes and recent updates in secondary prevention recommendations including short term use of dual antiplatelet therapy to prevent recurrent stroke in the high risk period immediately after stroke. Finally, we discuss emerging therapies and questions for future research.

ADAPT with New Catalyst 5 Reperfusion Catheter for Distal M2 Ischemic Stroke: Preliminary Experience

OBJECTIVE

We sought to assess preliminary technical and clinical outcomes of Catalyst 5 (CAT 5) as front-line aspiration treatment for M2-M3 occlusion in acute ischemic stroke.

METHODS

Patients with symptomatic stroke and distal M2 or M3 occlusions were enrolled retrospectively. A direct aspiration first-pass technique was used as the first treatment option for absolute contraindication to intravenous fibrinolytic therapy. Time to recanalization, first attempt recanalization, and number of attempts were recorded. Successful recanalization was defined as a modified thrombolysis in cerebral infarction score ≥2b; incidence of procedure-related complications was recorded. National Institutes of Health Stroke Scale at discharge and modified Rankin Scale score at 90 days were evaluated by a dedicated neurologist.

RESULTS

A total of 11 acute occlusions of distal M2-M3 segment were treated with a direct aspiration first-pass technique using CAT 5 (mean age 69.3 years). Tandem occlusion was present in 2 cases. Intracranial preocclusive mean vessel diameter was 1.9 mm. Overall modified thrombolysis in cerebral infarction score ≥2b was obtained in 72.7% of patients with mean time to recanalization of 36.4 minutes and a mean of 1.9 attempts. First-attempt recanalization with CAT 5 was obtained in 54% of patients with a mean time to recanalization of 29.2 minutes. A stent retriever with proximal aspiration was incorporated as a rescue device in 2 cases. Embolization of new territories was reported after CAT 5 aspiration in 1 patient. No intracranial hemorrhage was detected on follow-up computed tomography. The median National Institutes of Health Stroke Scale score at discharge was 3. At 90 days, a modified Rankin Scale score of 0-2 was achieved in 90.9% of patients.

CONCLUSIONS

Preliminary experience using CAT 5 in distal occlusions demonstrates that it may be safe and effective in acute stroke treatment.

ADAPT technique in ischemic stroke treatment of M2 middle cerebral artery occlusions in comparison to M1 occlusions: Post hoc analysis of the PROMISE study

Background/purpose

The benefit of endovascular thrombectomy in acute ischemic stroke (AIS) therapy of proximal large vessel occlusions (LVO) is established. However, there are few prospective studies evaluating the use of a direct aspiration first pass technique in distal vessel occlusions. This post hoc analysis of the PROMISE study examines the safety and effectiveness of the Penumbra System with the ACE68 and ACE64 Reperfusion Catheters for aspiration thrombectomy in the M1 and M2 segments of the middle cerebral artery.

Methods

PROMISE is a prospective, multicenter study that enrolled 204 patients with anterior circulation LVO AIS-treated frontline with ACE68/ACE64 catheters. We compared clinical and angiographic outcomes, complications, and mortality in patients with M1 and M2 occlusions. The association of M1 and M2 location and functional independence or mTICI 2b-3 reperfusion was described in univariable and multivariable analyses.

Results

One hundred sixty-one patients (124 M1 and 37 M2 locations) met the study criteria. Post procedure mTICI 2b-3 reperfusion (93% vs. 92%, p = 1.00), functional independence (57% vs. 70%, p = 0.18), symptomatic intracranial hemorrhage (1.6% vs. 2.7%, p = 0.55), device- or procedure-related serious adverse events at 30 days (4.0% vs. 8.1%, p = 0.39), and mortality at 90 days (6.6% vs. 2.7%, p = 0.69) were comparable between M1 and M2 occlusions. In multivariable analysis, lower age, lower baseline NIHSS, and shorter time from onset to admission were independent predictors of functional independence.

Conclusions

For frontline aspiration thrombectomy of stroke, use of large-bore ACE68/ACE64 catheters for treatment of M2 occlusions appeared as safe and effective as for M1 occlusions.

Mechanical thrombectomy with second-generation devices for acute cerebral middle artery M2 segment occlusion: A meta-analysis

BACKGROUND

The benefit of mechanical thrombectomy for an acute ischemic stroke involving M2 segment occlusion is not clear, especially when performed with second-generation thrombectomy devices.

METHOD

We reviewed the literature to investigate clinical outcomes and the rates of recanalization, symptomatic intracerebral hematoma, and mortality in mechanical thrombectomy performed using second-generation thrombectomy devices. We compared the outcomes between patients treated for M2 and M1 occlusions.

RESULTS

Seven studies involving 805 patients with M2 thrombectomy were included in this meta-analysis. The functional independence rate 90 days after thrombectomy (modified Rankin Scale 0-2) was 59.3% (OR 1.81, 95% CI 1.74-1.88). The recanalization rate (thrombolysis in cerebral infarction 0-2) was 84.16% (OR 2.32, 95% CI 2.08-2.29). The symptomatic intracerebral hematoma rate was 4.9% (OR 1.05, 95% CI 1.03-1.09). The mortality was 7.7% (OR 1.08, 95% CI 1.03-1.13). The outcomes were better in patients with M2 occlusion than in those with M1 occlusion. In a subgroup analysis, we found that among patients with hypertension, mechanical thrombectomy achieved better functional outcomes and recanalization in M2 occlusion than M1 occlusion.

CONCLUSION

Mechanical thrombectomy performed with second-generation thrombectomy devices for M2 occlusion can provide a good functional outcome as well as satisfying recanalization. Moreover, there was no significant difference in the symptomatic intracerebral hematoma and mortality rates, suggesting this procedure is as safe in M2 occlusion as in M1 occlusion.

Mechanical Thrombectomy of Distal Occlusions Using a Direct Aspiration First Pass Technique Compared with New Generation of Mini-0.017 Microcatheter Compatible-Stent Retrievers: A Meta-Analysis

BACKGROUND

There are no current evidence-based recommendations on mechanical thrombectomy (MT) in M2 or other distal occlusions. The objective of this paper was to investigate clinical and radiologic outcomes of MT in distal locations using the new generation of mini-0.017 microcatheter compatible-stent retrievers (SRs) compared with a direct aspiration first pass technique (ADAPT) MT.

METHODS

A systematic search was performed for studies published from January 2016 to March 2019. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies that reported clinical and radiologic outcomes of patients undergoing MT using new generation of SRs or ADAPT in distal locations. The cumulative prevalence was estimated for each outcome. Heterogeneity of the data was assessed by the Higgins index (I²), and a random-effects model was applied.

RESULTS

Fifteen studies and 494 patients were included; 7 studies reported on patients treated with a new SR and 8 studies analyzed patients treated with ADAPT. The rate of thrombolysis in cerebral infarction score 2b-3 after MT for distal occlusions was 80.6% (383 of 494; 95% confidence interval [CI], 74.8%-86.3%; I² = 64.4%). Successful recanalization was comparable after SR use with low-profile devices and ADAPT (176 of 226; 82%; 95% CI, 72.6%-1.5%; I² = 70.5% vs. 207 of 268; 79.4%; 95% CI, 71.8%-86.9%; I² = 60.8%, respectively; P = 0.4). The rate of the modified Rankin scale score of 0-2 at 3 months was higher in the ADAPT group (160 of 251; 68.9%; 95% CI, 51.8%-85.9%; I² = 92.2%) than the SR group (92 of 177; 58.7%; 95% CI, 37.3%-80%; I² = 58.7%; P = 0.01). The mortality rate was lower among the ADAPT group (20 of 251; 5.4%; 95% CI, 1.4%-9%; I² = 63%) than the SR group (16 of 108; 13%; 95% CI, 6%-19%; I² = 13%; P = 0.008).

CONCLUSIONS

MT in distal locations using the new generation of SR yields comparable results compared with ADAPT in terms of recanalization; however, the use of SR is associated with lower functional independence and higher mortality rate.

Stent Retriever-Assisted Continuous Aspiration for Distal Intracranial Vessel Embolectomy: The Distal Combined Technique

OBJECTIVE

We investigated the efficacy of a combined approach with stent retriever-assisted aspiration catheter for distal intracranial vessel occlusion (distal combined technique [DCT]).

METHODS

We evaluated consecutive patients with acute ischemic stroke with distal occlusion in anterior circulation, including occlusions of the M2/M3 or A2/A3 segments, who received endovascular therapy (EVT) in a single center. Modified Thrombolysis in Cerebral Infraction (mTICI) score including TICI 2C category, processing time from puncture to reperfusion, proportion of a favorable clinical outcome at discharge (modified Rankin Scale [mRS] score ≤2), and incidence of symptomatic intracranial hemorrhage (sICH) were compared between the DCT and single device approach technique (non-DCT) groups.

RESULTS

Of 65 patients, 28 were treated with EVT using the DCT and 37 were treated with EVT with a single device approach (non-DCT). In the DCT group, a higher reperfusion rate at the first pass (mTICI score ≥2B, 92% vs. 54%; P = 0.0008; mTICI score ≥2C, 71% vs. 16%; P < 0.0001; mTICI score 3, 57% vs. 14%; P = 0.0004) and shorter time from puncture to successful reperfusion (median, 31 vs. 43 minutes; P = 0.0006) were achieved, respectively. The final successful reperfusion rate was also higher in the DCT group than in the non-DCT group (mTICI score ≥2C, 85% vs. 51%; P = 0.004; mTICI score 3, 75% vs. 43%; P = 0.012), respectively. sICH occurred in 2 patients in the non-DCT group. Patients with mRS score ≤2 at discharge were more prevalent in the DCT than in the non-DCT group (57% vs. 27%, respectively; P = 0.021).

CONCLUSIONS

This retrospective analysis indicated that the DCT is a useful and safe strategy for patients with distal anterior intracranial vessel occlusion.