Endovascular Treatment of Atherosclerotic Tandem Occlusions in Anterior Circulation Stroke: Technical Aspects and Complications Compared to Isolated Intracranial Occlusions

Repeated Re-occlusion during the Procedure of Mechanical Thrombectomy with Retrograde Approach for Tandem Occlusion Including T Occlusion: A Case Report

Objective

Two mechanical thrombectomy techniques are proposed for tandem occlusion of the anterior circulation: treating the extracranial carotid artery lesion first via an antegrade approach and treating the intracranial lesion first via a retrograde approach. Previous reports show that the retrograde approach has a shorter reperfusion time and a better prognosis, but re-occlusion of the intracranial lesion after recanalization may occur. We describe a case of tandem occlusion with repeated intracranial occlusions for mechanical thrombectomy using the retrograde approach and discuss possible countermeasures.

Case Presentation

A 94-year-old woman presented with acute cerebral ischemia due to tandem carotid T occlusion of the left internal carotid artery (ICA) and severe stenosis of the cervical carotid artery. Mechanical thrombectomy via a retrograde approach was performed using a stent retriever, resulting in complete recanalization of the anterior circulation through the ICA after 1 pass. The thrombus dispersed distally from the cervical artery and re-occluded the M1 twice, requiring thrombus re-retrieval each time.

Conclusion

The retrograde approach to tandem occlusion can result in repeated re-occlusion after recanalization of the intracranial lesion. Thrombi in cervical carotid lesions are usually fragile. Prior thrombus aspiration from the balloon guiding catheter at the carotid lesion may prevent re-occlusion after recanalization of the intracranial lesion without sacrificing the time advantage of early recanalization via the retrograde approach.

Platelet-Function-Monitoring-Guided Therapy After Emergent Carotid Artery Stenting

Background/Objectives: Antiplatelet therapy after emergent carotid stenting (eCAS) represents a challenge in balancing the risk of intracerebral hemorrhages (ICHs) and in-stent thrombosis (IST). Post-procedural platelet function monitoring may guide antiplatelet therapy and could potentially improve outcomes due to fewer post-procedural complications. Methods: Consecutive eCAS patients (2019-2021) were included in a single-center retrospective observational study. Patients treated with eCAS received peri-procedural eptifibatide followed by dual antiplatelet treatment with aspirin and clopidogrel. The effect of platelet ADP inhibition by clopidogrel was monitored using the Multiplate® Analyzer (Roche). Clopidogrel non-responders were changed to ticagrelor treatment. The primary outcome was defined as a favorable outcome at 90 days using the modified Rankin Scale (mRS) of 0-2 versus 3-6. Safety outcomes included ICH, IST, and mortality. Data were analyzed and compared in clopidogrel- and ticagrelor-treated patients using Fischer's exact test and multivariate logistic regression. Results: A total of 105 patients had eCAS, and 28 patients (27%) were clopidogrel non-responders and were changed to treatment with ticagrelor. The favorable outcome was more frequent in ticagrelor-treated patients, 23 (82%), than in clopidogrel-treated patients, 44 (57%), p = 0.036. Numerically, ICH, IST, and mortality were more frequent in clopidogrel-treated patients, but none of the differences were statistically significant. In multivariate analyses, ticagrelor treatment was significantly associated with the favorable outcome, OR = 3.89 (95% CI: 1.09-13.86), p = 0.036. Conclusions: One in four eCAS patients were clopidogrel non-responders. This study suggests that personalized antiplatelet treatment therapy was safe, and that changing treatment to ticagrelor in clopidogrel non-responders was associated with better outcomes in eCAS patients.

Some minutes matter more: Groin-to-recanalization is the main time-related predictor of outcome in acute ischemic stroke

INTRODUCTION

Endovascular thrombectomy (EVT) is the standard of care for selected patients with acute ischemic stroke (AIS) and large vessel occlusion (LVO), associated with intravenous thrombolysis, when indicated. While many studies focused on pre-hospital and in-hospital pathways, only few analyzed the relationship between groin-to-recanalization (GTR) time and functional outcome.

AIM

To explore whether GTR time is an independent predictor of outcome in patients undergoing EVT.

METHODS

All patients with anterior circulation stroke treated with EVT at a high-volume center from January 2021 to December 2023 were included. The cohort was divided into two groups according to GTR time shorter or longer than 30 min. Regression analysis assessed the association between GTR time and 3-month good outcome, defined as modified Rankin Scale 0-2.

RESULTS

The study included 419 patients. The groups had similar baseline characteristics and similar onset to recanalization (OTR) time. Regression analysis showed shorter GTR time is an independent predictor of favorable outcome (OR 2.49 [95% CI 1.26-4.94]). Age, baseline NIHSS, ASPECT score and bridging IVT were also found to be independently associated with outcome.

DISCUSSION AND CONCLUSIONS

Our study showed GTR time is an independent predictor of good outcome in patients undergoing EVT with similar OTR time, emphasizing procedural time as a key prognostic factor, even greater than other well-known pre-hospital and in-hospital time-dependent variables. These findings may raise the issue of developing alternative approaches or early "rescue" strategies for complicated procedures.

Acute carotid stenting versus non-stenting treatment of acute ischemic stroke due to tandem lesions: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness and safety of acute carotid stenting (ACS) in comparison to non-stenting interventions for patients experiencing acute ischemic stroke (AIS) caused by tandem lesions (TL).

METHODS

A systematic review of literature from PubMed, Embase, and Cochrane databases was conducted to identify relevant studies published up to October 10, 2023. The comparison between ACS and no stenting in patients with TL undergoing endovascular therapy (EVT) focused on outcomes, such as 90-day modified Rankin Scale (mRS) score, successful recanalization, symptomatic intracerebral hemorrhage (sICH), and 90-day mortality.

RESULTS

The final analysis encompassed a total of 3,187 patients from 21 studies, with 1,786 patients classified as ACS patients and 1,401 as non-stent patients. The overall treatment effect favored the ACS group, as evidenced by their association with improved functional independence at 90 days (mRS 0-2) [relative risk (RR) = 1.18; 95% confidence interval (CI) 1.05-1.34; P < 0.05; I2 = 44%] and a higher rate of successful recanalization [modified Thrombolysis in Cerebral Infarction (mTICI) ≥ 2b/3] (RR = 1.16; 95% CI 1.09-1.25; P < 0.05; I2 = 40%). The risk of sICH was not significantly different between the two groups (RR = 1.28; 95% CI 0.98-1.68; P > 0.05; I2 = 0%). Additionally, there was no significant difference in 90-day mortality between the two groups (RR = 0.78; 95% CI 0.58-1.07; P > 0.05; I2 = 45%).

CONCLUSION

Among TL patients undergoing EVT, ACS may be associated with better functional outcomes at 90 days compared with no stenting.

Mediation Analysis of Acute Carotid Stenting in Tandem Lesions: Effect on Functional Outcome in a Multicenter Registry

BACKGROUND AND OBJECTIVES

Current evidence suggests that acute carotid artery stenting (CAS) for cervical lesions is associated with better functional outcomes in patients with acute stroke with tandem lesions (TLs) treated with endovascular therapy (EVT). However, the underlying causal pathophysiologic mechanism of this relationship compared with a non-CAS strategy remains unclear. We aimed to determine whether, and to what degree, reperfusion mediates the relationship between acute CAS and functional outcome in patients with TLs.

METHODS

This subanalysis stems from a multicenter retrospective cohort study across 16 stroke centers from January 2015 to December 2020. Patients with anterior circulation TLs who underwent EVT were included. Successful reperfusion was defined as a modified Thrombolysis in Cerebral Infarction scale ≥2B by the local team at each participating center. Mediation analysis was conducted to examine the potential causal pathway in which the relationship between acute CAS and functional outcome (90-day modified Rankin Scale) is mediated by successful reperfusion.

RESULTS

A total of 570 patients were included, with a median age (interquartile range) of 68 (59-76), among whom 180 (31.6%) were female. Among these patients, 354 (62.1%) underwent acute CAS and 244 (47.4%) had a favorable functional outcome. The remaining 216 (37.9%) patients were in the non-CAS group. The CAS group had significantly higher rates of successful reperfusion (91.2% vs 85.1%; p = 0.025) and favorable functional outcomes (52% vs 29%; p = 0.003) compared with the non-CAS group. Successful reperfusion was a strong predictor of functional outcome (adjusted common odds ratio [acOR] 4.88; 95% CI 2.91-8.17; p < 0.001). Successful reperfusion partially mediated the relationship between acute CAS and functional outcome, as acute CAS remained significantly associated with functional outcome after adjustment for successful reperfusion (acOR 1.89; 95% CI 1.27-2.83; p = 0.002). Successful reperfusion explained 25% (95% CI 3%-67%) of the relationship between acute CAS and functional outcome.

DISCUSSION

In patients with TL undergoing EVT, successful reperfusion predicted favorable functional outcomes when CAS was performed compared with non-CAS. A considerable proportion (25%) of the treatment effect of acute CAS on functional outcome was found to be mediated by improvement of successful reperfusion rates.

Outcomes in acute carotid-related stroke eligible for mechanical reperfusion: SAFEGUARD-STROKE Registry

BACKGROUND

Carotid-related strokes (CRS) are largely unresponsive to intravenous thrombolysis and are often large and disabling. Little is known about contemporary CRS referral pathways and proportion of eligible patients who receive emergency mechanical reperfusion (EMR).

METHODS

Referral pathways, serial imaging, treatment data, and neurologic outcomes were evaluated in consecutive CRS patients presenting over 18 months in catchment area of a major carotid disease referral center with proximal-protected CAS expertise, on-site neurology, and stroke thrombectomy capability (Acute Stroke of CArotid Artery Bifurcation Origin Treated With Use oF the MicronEt-covered CGUARD Stent - SAFEGUARD-STROKE Registry; companion to SAFEGUARD-STROKE Study NCT05195658).

RESULTS

Of 101 EMR-eligible patients (31% i.v.-thrombolyzed, 39.5% women, age 39-89 years, 94.1% ASPECTS 9-10, 90.1% pre-stroke mRS 0-1), 57 (56.4%) were EMR-referred. Referrals were either endovascular (Comprehensive Stroke Centre, CSC, 21.0%; Stroke Thrombectomy-Capable CAS Centre, STCC, 70.2%) or to vascular surgery (VS, 1.8%), with >1 referral attempt in 7.0% patients (CSC/VS or VS/CSC or CSC/VS/STCC). Baseline clinical and imaging characteristics were not different between EMR-treated and EMR-untreated patients. EMR was delivered to 42.6% eligible patients (emergency carotid surgery 0%; STCC rejections 0%). On multivariable analysis, non-tandem CRS was a predictor of not getting referred for EMR (OR 0.36; 95%CI 0.14-0.93, P=0.03). Ninety-day neurologic status was profoundly better in EMR-treated patients; mRS 0-2 (83.7% vs. 34.5%); mRS 3-5 (11.6% vs. 53.4%), mRS 6 (4.6% vs. 12.1%); P<0.001 for all.

CONCLUSIONS

EMR-treatment substantially improves CRS neurologic outcomes but only a minority of EMR-eligible patients receive EMR. To increase the likelihood of brain-saving treatment, EMR-eligible stroke referral and management pathways, including those for CSC/VS-rejected patients, should involve stroke thrombectomy-capable centres with endovascular carotid treatment expertise.

Elective carotid stenting fulfills quality standards defined in guidelines

PURPOSE

According to evidence from randomized trials and current guidelines, elective carotid artery stenting (CAS) is still considered second-line therapy compared with carotid endarterectomy (CEA). However, the publication of randomized comparative trials for patients with symptomatic stenoses occurred well over 10 years ago. In view of problems regarding German quality assurance when differentiating elective from emergency interventions and low case numbers for CAS indications, it seemed reasonable to present neurologically controlled CAS results and to investigate whether elective CAS consistently fulfills the strict quality criteria and what differences exist with respect to emergency CAS interventions in acute ischemic stroke.

MATERIALS AND METHODS

Between 01/2012 and 07/2022, 141 elective CAS procedures were performed to treat patients with symptomatic (n = 123) and asymptomatic (n = 18) stenoses. Protection by a filter system was achieved in 134 of these elective procedures (95 %). During the same period, 158 patients underwent carotid stenting for acute stroke. Complication rates were determined using neurologically controlled data. CAS-related complications (stent thrombosis, stent-associated vascular damage, thromboembolism, and symptomatic hemorrhage) were extracted from emergency interventions, and clinical outcome (NIHSS progression) was determined during the inpatient stay.

RESULTS

The rate of stroke and death determined during the inpatient stay for elective symptomatic patients was 0.8 %. Early treatment within the first 7 days after the index event, age > 70 years, and operator experience were not significant risk factors for the occurrence of complications. No complications were observed after CAS of asymptomatic stenoses. The procedure-related complication rate for emergency procedures was 7.8 %, which was significantly higher than after elective CAS, as expected (p < 0.006).

CONCLUSION

Even with limited indications and limited case numbers, compliance with the strict quality criteria of the current S3 Guideline 2022 for elective CAS interventions is possible for both symptomatic and asymptomatic stenoses in an experienced center. Emergency CAS interventions have significantly higher complication rates under other conditions and must be considered separately with regard to quality assurance.

KEY POINTS

· Elective carotid stenting fulfills the strict quality criteria of the current S3 guideline 2022.. · Emergency carotid stenting has significantly higher complication rates than elective procedures.. · Elective and emergency carotid stenting cannot be meaningfully compared..

CITATION FORMAT

· Keil F, Stahn S, Reitz SC et al. Elective carotid stenting fulfills quality standards defined in guidelines. Fortschr Röntgenstr 2024; 196: 471 - 481.

Development of a Novel Statistical Model for Predicting Clinical Outcomes in Stroke Patients With Tandem Occlusions After Endovascular Therapy

BACKGROUND

Tandem occlusions are intracranial large vessel occlusions (LVOs) with a concomitant ipsilateral extracranial internal carotid artery occlusion and can cause more severe stroke symptoms.

AIM

To develop a simple, rigorously cross-validated novel tool to predict clinical outcomes following tandem occlusion in patients with acute LVO stroke, based on data that are easily available to clinicians. To have used machine learning approaches to utilize the available information from clinical and angiographic data to make predictive models able to distinguish between mortality versus survival and good (modified Rankin Scale (mRS) ≤ 2) versus unfavorable neurological outcomes (mRs ≥ 3) Materials and methods: Retrospective data from 87 consecutive patients with anterior circulation stroke and tandem occlusions who underwent mechanical thrombectomy and stenting between December 2009 and January 2020 were analyzed. Patients were stratified into three groups based on the location of their LVO, and these groups were compared using statistical tests. Predictive models were built and cross-validated 1000 times to estimate their predictive power, measured by accuracy and area under the receiver operating curve (AUROC).

RESULTS

For distinguishing good outcome (mRS ≤ 2) versus poor outcome (mRS ≥ 3), the model comprised age, initial National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early CT Score (ASPECTS), NIHSS at 24 hours, NIHSS at discharge and intracranial haemorrhage and yielded an accuracy of 83% and the AUROC of 0.91. For mortality prediction, the model comprised age, initial NIHSS, intravenous thrombolysis, NIHSS at 24 hours and NIHSS at discharge and yielded an accuracy of 91% and an AUROC of 0.94.

CONCLUSIONS

Models developed exhibit strong predictive performance and can distinguish between both the instances of survival versus mortality and good versus poor outcome with an aim to support clinicians in deciding on optimal management for these complex patients. The developed model will help identify those at risk of poorer outcomes and the prospective better selection of patients with acute ischaemic large vessel stroke secondary to tandem occlusions.

Age and Stroke Severity Matter Most for Clinical Outcome in Acute Arteriosclerotic Tandem Lesions

Background: Tandem lesions (TLs) cause up to 15-30% of all acute ischemic strokes (AISs). Endovascular treatment (EVT) is regarded as the first-line treatment; however, uncertainties remain with respect to the treatment and predictive outcome parameters. Here, we aimed to identify the clinical and demographic factors associated with functional short- and long-term outcomes in AIS patients with arteriosclerotic TLs undergoing EVT. Methods: This was a retrospective, mono-centric cohort study of 116 consecutive AIS patients with arteriosclerotic TLs who were endovascularly treated at a stroke center, with analysis of the relevant demographic, procedural, and imaging data. Results: A total of 116 patients were included in this study, with a median age of 72 years (IQR 63-80), 31% of whom were female (n = 36). The median NIHSS on admission was 14 (IQR 7-19), with a median ASPECT score of 9 (IQR 8-10) and median NASCET score of 99% (IQR 88-100%). A total of 52% of the patients received intravenous thrombolysis. In 77% (n = 89) of the patients, an antegrade EVT approach was used, with a good recanalization (mTICI2b3) achieved in 83% of patients (n = 96). Symptomatic intracerebral hemorrhage occurred in 12.7% (n = 15) of patients. A favorable outcome (mRS0-2) and mortality at 3 months were obtained for 40% (n = 47) and 28% of patients (n = 32), respectively. Age and NIHSS on admission were strongly associated with outcome parameters. Diabetes mellitus and previous neurological disorders were independently associated with long-term mortality (median 11 months, IQR 0-42). Conclusions: Younger age, lower stroke severity, and good recanalization were found to be independently associated with a favorable outcome. In contrast, older age, higher stroke severity, previous neurological disorders, and diabetes were correlated with mortality. The endovascular treatment of acute arteriosclerotic tandem lesions is feasible and relatively safe.

Endovascular revascularization of vertebrobasilar tandem occlusions in comparison to isolated basilar artery occlusions: A multi-center experience

BACKGROUND

Acute basilar artery occlusion (BAO) is a severe disease that is associated with an 85% mortality rate if untreated. Several studies have analyzed the use of mechanical thrombectomy (MT) in the different scenarios of BAO. However, the results remain conflicting and the role of MT as standard of care for vertebrobasilar tandem occlusions (VBTO) has not been confirmed. Our goal was to assess technical feasibility, safety, and functional outcome of endovascular treatment of VBTO in comparison to isolated BAO (IBAO).

METHODS

We retrospectively reviewed all prospectively collected patients with acute BAO from six tertiary centers between September 2016 and November 2021. Patients were subsequently divided into two groups: VBTO and IBAO. Baseline data, procedural details, and outcomes were compared between groups.

RESULTS

A total of 190 patients were included, 55 presenting with a VBTO and 135 with IBAO. Successful recanalization was equally common in both groups (89.1% and 86.0%). Rates of favorable functional outcome (modified Rankin Scale: 0-2) were higher in patients with VBTO compared to IBAO (36.4% vs. 25.2%, p = 0.048) and mortality was lower (29.1% vs. 33.3%). However, these associations faded after adjustment for confounders (adjusted odds ratio [aOR] 0.86, 95% CI 0.35-2.05; aOR 0.93, 95% CI 0.35-2.45). Rates of symptomatic intracranial hemorrhage did not differ between the groups (VBTO: 7.3% vs. IBAO: 4.2%; p = 0.496).

CONCLUSION

Endovascular treatment of VBTO is technically feasible and safe with similar rates of successful recanalization, favorable functional outcome, and mortality to those in patients with IBAO.

Antithrombotic regimen in emergent carotid stenting for acute ischemic stroke due to tandem occlusion: a meta-analysis of aggregate data

BACKGROUND

The periprocedural antithrombotic regimen might affect the risk-benefit profile of emergent carotid artery stenting (eCAS) in patients with acute ischemic stroke (AIS) due to tandem lesions, especially after intravenous thrombolysis. We conducted a systematic review and meta-analysis to evaluate the safety and efficacy of antithrombotics following eCAS.

METHODS

We followed PRISMA guidelines and searched MEDLINE, Embase, and Scopus from January 1, 2004 to November 30, 2022 for studies evaluating eCAS in tandem occlusion. The primary endpoint was 90-day good functional outcome. Secondary outcomes were symptomatic intracerebral hemorrhage, in-stent thrombosis, delayed stent thrombosis, and successful recanalization. Meta-analysis of proportions and meta-analysis of odds ratios were implemented.

RESULTS

34 studies with 1658 patients were included. We found that the use of no antiplatelets (noAPT), single antiplatelet (SAPT), dual antiplatelets (DAPT), or glycoprotein IIb/IIIa inhibitors (GPI) yielded similar rates of good functional outcomes, with a marginal benefit of GPI over SAPT (OR 1.88, 95% CI 1.05 to 3.35, Pheterogeneity=0.31). Sensitivity analysis and meta-regression excluded a significant impact of intravenous thrombolysis and Alberta Stroke Program Early CT Score (ASPECTS). We observed no increase in symptomatic intracerebral hemorrhage (sICH) with DAPT or GPI compared with noAPT or SAPT. We also found similar rates of delayed stent thrombosis across groups, with acute in-stent thrombosis showing marginal, non-significant benefits from GPI and DAPT over SAPT and noAPT.

CONCLUSIONS

In AIS due to tandem occlusion, the periprocedural antithrombotic regimen of eCAS seems to have a marginal effect on good functional outcome. Overall, high intensity antithrombotic therapy may provide a marginal benefit on good functional outcome and carotid stent patency without a significant increase in risk of sICH.

A propensity score-matched comparative study of balloon guide catheters versus conventional guide catheters for concurrent mechanical thrombectomy with carotid stenting in tandem strokes: comparison of first pass effect, symptomatic intracranial hemorrhage, and 90-day functional outcomes

BACKGROUND

Extensive clot burden in tandem strokes accounts for poor mechanical thrombectomy (MT) outcomes. Several studies have shown the benefit of balloon guide catheters (BGCs) in MT and carotid artery stenting.

OBJECTIVE

In view of this potential benefit, to investigate the safety and effectiveness of proximal flow arrest using a BGC during concurrent MT and carotid revascularization for tandem stroke treatment in a comparative, propensity score-matched (PSM) study.

METHODS

Patients with a tandem stroke identified from our endovascular database were dichotomized into groups treated with BGCs versus conventional guide catheters. One-to-one PSM adjustment for baseline demographics and treatment selection bias using nearest-neighbor matching was performed. Patient demographics, presentation characteristics, and procedural details were recorded. Outcomes assessed were final modified Thrombolysis in Cerebral Infarction (mTICI) grade, periprocedural symptomatic intracranial hemorrhage (sICH) rate, in-hospital mortality, and 90-day modified Rankin Scale (mRS) score. Mann-Whitney U test and multivariate logistic regression were performed to compare procedural parameters and clinical outcomes.

RESULTS

Concurrent carotid revascularization (stenting with/without angioplasty) and MT was performed in 125 cases (BGC: 85; no BGC: 40). After PSM (40 patients/group), the BGC group had a significantly shorter procedure duration (77.9 vs 61.5 min; OR=0.996; P=0.006), lower discharge National Institutes of Health Stroke Scale score (8.0 vs 11.0; OR=0.987; P=0.042), and higher odds of 90-day mRS 0-2 score (52.3% vs 27.5%; OR=0.34; P=0.040). On multivariate regression, the BGC group had a significantly higher first pass effect rate (mTICI 2b or 3)(OR=1.115, 95% CI 1.015 to 1.432; P=0.013) and lower periprocedural sICH rate (OR=0.615, 95% CI 0.406 to 0.932; P=0.025). No difference in in-hospital mortality was observed (OR=1.591, 95% CI 0.976 to 2.593; P=0.067).

CONCLUSION

BGCs used for concurrent MT-carotid revascularization with flow arrest were safe and resulted in superior clinical and angiographic outcomes in patients with a tandem stroke.

Statistical analysis plan for the multicenter, open, randomized controlled clinical trial to assess the efficacy and safety of intravenous tirofiban vs aspirin in acute ischemic stroke due to tandem lesion, undergoing recanalization therapy by endovascular treatment (ATILA trial)

RATIONALE

In-stent reocclusion after endovascular therapy has a negative impact on outcomes in acute ischemic stroke (AIS) due to tandem lesions (TL). Optimal antiplatelet therapy approach in these patients to avoid in-stent reocclusion is yet to be elucidated.

AIMS

To assess efficacy and safety of intravenous tirofiban versus intravenous aspirin in patients undergoing MT plus carotid stenting in the setting of AIS due to TL.

SAMPLE SIZE ESTIMATES

Two hundred forty patients will be enrolled, 120 in every treatment arm.

METHODS AND DESIGN

A multicenter, prospective, randomized, controlled (aspirin group), assessor-blinded clinical trial will be conducted. Patients fulfilling the inclusion criteria will be randomized at MT onset to the experimental or control group (1:1). Intravenous aspirin will be administered at a 500-mg single dose and tirofiban at a 500-mcg bolus followed by a 200-mcg/h infusion during the first 24 h. All patients will be followed for up to 3 months.

STUDY OUTCOMES

Primary efficacy outcome will be the proportion of patients with carotid in-stent thrombosis within the first 24 h after MT. Primary safety outcome will be the rate of symptomatic intracranial hemorrhage.

DISCUSSION

This will be the first clinical trial to assess the best antiplatelet therapy to avoid in-stent thrombosis after MT in patients with TL.

TRIAL REGISTRATION

The trial is registered as NCT05225961. February, 7th, 2022.

Immediate Carotid Artery Stenting or Deferred Treatment in Patients With Tandem Carotid Lesions Treated Endovascularly for Acute Ischaemic Stroke

Fifteen to 20% of patients with an acute ischaemic stroke have a tandem lesion defined by the combination of an intracranial large vessel thrombo-embolic occlusion and a high grade stenosis or occlusion of the ipsilateral internal carotid artery. These patients tend to have worse outcomes than patients with isolated intracranial occlusions, with higher rates of disability and death. The introduction of endovascular thrombectomy to treat the intracranial lesion clearly improved the outcome compared with treatment with intravenous thrombolysis alone. However, the best treatment strategy for managing the extracranial carotid artery lesion in patients with tandem lesions remains unknown. Current guidelines recommend carotid endarterectomy for patients with transient ischaemic attack or non-disabling stroke and moderate or severe stenosis of the internal carotid artery, within two weeks of the initial event, to prevent major stroke recurrence and death. Alternatively, the symptomatic carotid artery could be treated by endovascular placement of a stent during endovascular thrombectomy (EVT). This would negate the need for a second procedure, immediately reduce the risk of stroke recurrence, increase patient satisfaction, and could be cost effective. However, the administration of dual antiplatelet therapy could potentially increase the risk of symptomatic intracranial haemorrhage in patients with acute ischaemic stroke. Randomised controlled trials evaluating the efficacy and safety of immediate carotid artery stenting during EVT in acute stroke patients with tandem lesions are currently ongoing and will impact the current guidelines regarding the treatment of patients with acute ischaemic stroke due to these tandem lesions.

Rendezvous intervention using combined surgical carotid endarterectomy followed by endovascular thrombectomy in patients with acute tandem occlusions: a proof-of-concept experience at a tertiary care center

BACKGROUND

Endovascular thrombectomy (EVT) is highly effective in acute stroke patients with intracranial large vessel occlusion (LVO), however, presence of concomitant cervical occlusion of the internal carotid artery (ICA) may limit the endovascular access. This study describes feasibility and efficacy of a surgical carotid access (cutdown) to perform interdisciplinary recanalization therapy including carotid endarterectomy (CEA) followed by EVT for recanalization of intracranial LVO in stroke patients with tandem occlusions.

METHODS

We identified stroke patients with tandem occlusions who underwent a combined surgical-endovascular approach over a 5-year period. Surgical cutdown was provided by a cardiovascular surgery team at the angio-suite followed by EVT performed by the neuroradiological team. Demographics, stroke characteristics, treatments including antithrombotic management, procedure times, and clinical follow-up were assessed.

RESULTS

Four patients with acute stroke because of tandem occlusions received CEA followed by EVT (two patients after frustrating femoral catheterization, two as first-line approach). Successful recanalization (TICI ≥ 2b) via endovascular thrombectomy was achieved in all patients at a median of 28 min after successful surgical CEA. Intraprocedural complication was observed in one case (25%; i.e. ICA dissection).

CONCLUSIONS

This small study provides evidence that a combined interdisciplinary approach of CEA followed by EVT in the angio-suite in acute stroke patients with tandem occlusions is a feasible procedure in patients otherwise not accessible to endovascular recanalizing therapy and, therefore, high likelihood of developing large hemispheric infarction. Prospective data are warranted to identify patients who benefit from this combined approach as first-line therapy.

Diagnosis and management of tandem occlusion in acute ischemic stroke

Approximately 20-30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Differences in risk factors and outcome after acute stroke in patients with tandem occlusion and those with isolated intracranial occlusion after endovascular treatment

OBJECTIVE

This study aimed to compare the clinical features, treatment, and clinical outcome of patients with tandem occlusion and isolated intracranial occlusion through endovascular treatment (EVT).

METHODS

Patients with acute cerebral infarction who received EVT in two stroke centers were retrospectively included. According to MRI or CTA results, the patients were divided into tandem occlusion group or isolated intracranial occlusion group. The baseline data, etiological classification, treatment, post-stroke complications, image features, and clinical outcome were compared. Multivariate logistic regression analysis was used to evaluate the related factors affecting the prognosis of patients with EVT.

RESULTS

Among 161 patients with acute cerebral infarction, there were 33 cases (20.5%) in the tandem occlusion group and 128 cases (79.5%) in the isolated intracranial occlusion group. Compared with isolated intracranial occlusion, the patients with tandem occlusion had higher rates of large artery atherosclerosis (P = 0.028), symptomatic intracerebral hemorrhage (sICH) (P = 0.023), bilateral infarction (P = 0.042), and longer time for endovascular procedure (P = 0.026). There was no significant statistical difference in 90-day mRS score between the two groups (P = 0.060). Multivariate logistic regression identified the following independent predictors of poor functional outcome: older age, high fasting blood glucose, infarction area > 1/3, and hemorrhagic transformation.

CONCLUSIONS

Compared with isolated intracranial occlusion, there was not a worse prognosis among patients with tandem occlusion who received EVT.

Emergent carotid stenting versus no stenting for acute ischemic stroke due to tandem occlusion: a meta-analysis

BACKGROUND

Emergent carotid artery stenting (eCAS) is performed during mechanical thrombectomy for acute ischemic stroke due to tandem occlusion. However, the optimal management strategy in this setting is still unclear.

OBJECTIVE

To carry out a systematic review and meta-analysis to investigate the safety and efficacy of eCAS in patients with tandem occlusion.

METHODS

Systematic review followed the PRISMA guidelines. Medline, EMBASE, and Scopus were searched from January 1, 2004 to March 7, 2022 for studies evaluating eCAS and no-stenting approach in patients with stroke with tandem occlusion. Primary endpoint was the 90-day modified Rankin Scale score 0-2; secondary outcomes were (1) symptomatic intracerebral hemorrhage (sICH), (2) recurrent stroke, (3) successful recanalization (Thrombolysis in Cerebral Infarction score 2b-3), (4) embolization in new territories, and (5) restenosis rate. Meta-analysis was performed using the Mantel-Haenszel method and random-effects modeling.

RESULTS

Forty-six studies reached synthesis. eCAS was associated with higher good functional outcome compared with the no-stenting approach (OR=1.52, 95% CI 1.19 to 1.95), despite a significantly increased risk of sICH (OR=1.97, 95% CI 1.23 to 3.15), and higher successful recanalization rate (OR=1.91, 95% CI 1.29 to 2.85). Restenosis rate was lower in the eCAS group than in the no-stenting group (2% vs 9%, p=0.001). Recanalization rate was higher in retrograde than antegrade eCAS (OR=0.51, 95% CI 0.28 to 0.93). Intraprocedural antiplatelets during eCAS were associated with higher rate of good functional outcome (60% vs 46%, p=0.016) and lower rate of sICH (7% vs 11%; p=0.08) compared with glycoprotein IIb/IIIa inhibitors.

CONCLUSIONS

In observational studies, eCAS seems to be associated with higher good functional outcome than no-stenting in patients with acute ischemic stroke due to tandem occlusion, despite the higher risk of sICH. Dedicated trials are needed to confirm these results.

Safety and Efficacy of Carotid Artery Stenting with the CGuard Double-layer Stent in Acute Ischemic Stroke

BACKGROUND

Double-layer stents show promising results in preventing periinterventional and postinterventional embolic events in elective settings of carotid artery stenting (CAS). We report a single-center experience with the CGuard stent in the treatment of acute ischemic stroke (AIS) due to symptomatic internal carotid artery (ICA) stenosis or occlusion with or without intracranial occlusion.

METHODS

We retrospectively analyzed all patients who received a CGuard stent in the setting of AIS at our institution. Neuroimaging and clinical data were analyzed with the following primary endpoints: technical feasibility, acute and delayed stent occlusion or thrombosis, distal embolism, symptomatic intracranial hemorrhage (sICH) and functional outcome at 3 months.

RESULTS

In 33 patients, stenting with the CGuard was performed. Stent deployment was successful in all patients (28 with tandem occlusions, 5 with isolated ICA occlusion). Transient acute in-stent thrombus formation occurred in three patients (9%) without early stent occlusion. Delayed, asymptomatic stent occlusion was seen in 1 patient (3%) after 49 days. Asymptomatic periinterventional distal emboli occurred in 2 patients (6%), 1 patient experienced a transient ischemic attack 79 days after the procedure and 1 patient (3%) developed sICH. Favorable clinical outcome (mRS 0-2) at 3 months was achieved in 12 patients (36%) and the mortality rate was 24%.

CONCLUSION

The CGuard use in emergencies was technically feasible, the safety has to be confirmed by further multicentric studies.

Effectiveness of Guiding Catheter Retrieval Balloon Technique in the Treatment of Acute Anterior Circulation Tandem Occlusion: A Retrospective Study

BACKGROUND

Tandem occlusion accounts for 10%-20% of all large vessel occlusion strokes and often yields a poor recanalization rate. The endovascular treatment of tandem lesions is still controversial. This study uses an endovascular treatment strategy, "guided catheter recovery balloon (GRB)" for the treatment of acute anterior circulation tandem occlusion.

METHODS

A retrospective design was adopted. The population included patients with acute tandem occlusion who received emergency GRB endovascular treatment. And the choice of stenting was made based on intraoperative radiography imaging. Recanalization was evaluated by the thrombolysis in cerebral infarction score after the operation. Three-month modified Rankin Scale follow-up results were recorded, and modified Rankin Scale ≤2 was considered favorable recovery.

RESULTS

A total of 55 patients aged 66.9 ± 8.5 years were enrolled, 37 of whom received stenting. The mean overall recanalization time was 46 minutes. Fifty (90.9%) patients achieved successful recanalization with a thrombolysis in cerebral infarction score of 2b-3. At the 3-month follow-up, the number of patients with favorable functional recovery was 28 (50.9%). The presence of hypertension was correlated with a favorable recovery outcome: 82.1% of the favorable recovery population had hypertension, and 55.6% of the unfavorable outcome population had hypertension (P = 0.033). There was no statistically significant association between stent application and favorable recovery outcomes (P = 0.504).

CONCLUSIONS

GRB technique showed a high recanalization rate when applied to the treatment of acute anterior circulation tandem occlusion.

Safety and efficacy of tirofiban in acute ischemic stroke due to tandem lesions undergoing mechanical thrombectomy: A multicenter randomized clinical trial (ATILA) protocol

Background

In-stent thrombosis after mechanical thrombectomy (MT) worsen outcomes in acute ischemic stroke (AIS) due to tandem lesions (TL). Although an optimal antiplatelet therapy is needed, the best approach to avoid in-stent thrombosis is yet to be elucidated.

Hypothesis

Low-dose intravenous tirofiban is superior to intravenous aspirin in avoiding in-stent thrombosis in patients undergoing MT plus carotid stenting in the setting of AIS due to TL.

Methods

The ATILA-trial is a multicenter, prospective, phase IV, randomized, controlled (aspirin group as control), assessor-blinded clinical trial. Patients fulfilling inclusion criteria (AIS due to TL, ASPECTS ⩾ 6, pre-stroke modified Rankin Scale ⩽2 and onset <24 h) will be randomized (1:1) at MT onset to experimental (intravenous tirofiban) or control group (intravenous aspirin). Intravenous aspirin will be administered at a 500 mg single dose and tirofiban at a 500 µg bolus followed by a 200 µg/h infusion during first 22 h. All patients will be followed up to 3 months. Sample size estimated is 240 patients.

Outcomes

The primary efficacy outcome is the proportion of patients with carotid in-stent thrombosis within the first 24 h after MT. The primary safety outcome is the rate of symptomatic intracranial hemorrhage. Secondary outcomes include functional independence defined as modified Rankin Scale 0-2, proportion of patients undergoing rescue therapy due to in-stent aggregation during MT and carotid reocclusion at 30 days.

Discussion

ATILA-trial will be the first clinical trial regarding the best antiplatelet therapy to avoid in-stent thrombosis after MT in patients with TL.

Trial registration

NCT0522596.

Outcome and risk of hemorrhage in patients with tandem lesions after endovascular treatment: A propensity score-matched case-control study

Objectives

Endovascular treatment of acute stroke patients with large vessel occlusions is well established. But tandem lesions of the internal carotid artery and the intracranial anterior circulation remain a challenge regarding the technical conditions and the putative higher risk of hemorrhage due to often required antiplatelet therapy.This study aims to evaluate the clinical outcome and the risk of hemorrhage after endovascular treatment of tandem lesions, with special regard to the periprocedural antiplatelet regimen.

Materials and Methods

In this retrospective study, we included 63 consecutive stroke patients with endovascular treated tandem lesions. One hundred eleven patients with a solitary intracranial occlusion were matched using a "propensity score-matched analysis" with the covariates sex, age, wake-up stroke, iv-thrombolysis and NIHSS.

Results

Rates of successful recanalization (mTICI 2b/3) and periprocedural complications were equal in both groups (P = 0.19; P = 0.35). The rate of good clinical outcome (mRS≤2) was similar, and the incidence of symptomatic hemorrhages was not significantly different (7.9% tandem lesions vs. 5.4% isolated intracranial occlusion, P = 0.51). Even intensified antiplatelet therapy in patients with tandem lesions did not increase the rate of symptomatic intracranial hemorrhages (P = 0.87).

Conclusions

Clinical outcome and symptomatic intracranial hemorrhages did not differ significantly between endovascular treated patients with tandem lesions and matched patients with solitary intracranial occlusions, regardless of the antiplatelet regimen. Therefore, the complex technical requirements for recanalization of a tandem lesion and the putative higher risk should not result in reluctant treatment that would decrease the chance of a good clinical outcome.

Acute Ischemic Stroke caused by Internal Carotid Artery Occlusion: Impact of Occlusion Type on the Prognosis

METHODS

We retrospectively reviewed 67 AIS patients who had an ICA occlusion on computed tomography angiography (CTA) and underwent MT in a single tertiary center. ICA occlusion types were categorized as 1) true cervical ICA (cICA) occlusion (true occlusion), 2) pseudo-occlusion of the cICA (pseudo-occlusion), and 3) distal ICA (dICA) occlusion. We compared the clinical characteristics and their outcomes according to the ICA occlusion type.

RESULTS

Fourteen patients were diagnosed with true occlusion, 32 with pseudo-occlusion, and 21 with dICA occlusion. The main etiologies were atherothrombotic in true occlusion (64.3%) and cardioembolic in pseudo-occlusion (81.3%) and dICA occlusion (71.4%) (p<0.001). Pseudo-occlusion showed lower rates of successful reperfusion (37.5%, p=0.009, 78.6% in true occlusion and 71.4% in dICA occlusion and poor functional outcome at 3 months (18.8%, p=0.037, 50% in true occlusion and 47.6% in dICA occlusion) with statistical significance. The infarction volume (169.4±154.4 mL, p=0.004, 29.2±52.7mL in true occlusion and 105.8±13.4mL in dICA occlusion) was significantly higher in pseudo-occlusion. On multivariate logistic analysis, pseudo-occlusion (OR: 4.84, 95% CI: 1.02-22.87, p=0.023) was an independent risk factor for poor reperfusion, which was significantly associated with a poor functional prognosis (odds ratio [OR]: 22.04, 95% confidence interval [CI]: 1.99-243.83, p=0.012).

CONCULSIONS

Patients with pseudo-occlusion showed poorer clinical outcomes compared to other ICA occlusion types, possibly due to a poor reperfusion rate after MT.

Endovascular treatment of ischemic stroke due to isolated internal carotid artery occlusion: ETIS registry data analysis

BACKGROUND

The best treatment for acute ischemic stroke (AIS) due to isolated cervical internal carotid artery occlusion (CICAO) (i.e., without associated occlusion of the circle of Willis) is still unknown. In this study, we aimed to describe EVT safety and clinical outcome in patients with CICAO.

METHODS

We analyzed data of all consecutive patients, included in the Endovascular Treatment in Ischemic Stroke (ETIS) Registry between 2013 and 2020, who presented AIS and proven CICAO on angiogram and underwent EVT. We assessed carotid recanalization, procedural complications, National Institutes of Health Stroke Scale (NIHSS) at 24 h post-EVT, and 3-month favorable outcome (modified Rankin Scale, mRS ≤ 2 or equal to the pre-stroke value).

RESULTS

Forty-five patients were included (median age: 70 years; range: 62-82 years). The median NIHSS before EVT was 14 (9-21). Carotid stenting was performed in 23 (51%) patients. Carotid recanalization at procedure end and on control imaging was observed in 37 (82%) and 29 (70%) patients, respectively. At day 1 post-EVT, the NIHSS remained stable or decreased in 25 (60%) patients; 12 (29%) patients had early neurologic deterioration (NIHSS ≥ 4 points). The rate of procedural complications was 36%, including stent thrombosis (n = 7), intracranial embolism (n = 7), and symptomatic intracranial hemorrhage (n = 1). At 3 months, 18 (40%) patients had a favorable outcome, and 10 (22%) were dead.

CONCLUSION

Our study suggests that EVT in AIS patients with moderate/severe initial deficit due to CICAO led to high rate of recanalization at day 1, and a 40% rate of favorable outcome at 3 months. There was a high rate of procedural complication which is of concern. Randomized controlled trials assessing the superiority of EVT in patients with CICAO and severe deficits are needed.

Antegrade or Retrograde Approach for the Management of Tandem Occlusions in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Background: Acute ischemic stroke (AIS) caused by tandem intracranial and extracranial occlusions is not rare. However, optimal strategy between antegrade (extracranial first) or retrograde (intracranial first) approaches still remains elusive. This systematic review and meta-analysis aim to compare the two approaches to provide updated clinical evidence of strategy selection. Methods: PubMed, Ovid, Web of Science, and the Cochrane Library were searched for literature comparing antegrade and retrograde approaches for patients with AIS with concomitant tandem occlusions. Outcomes including successful reperfusion [Throbolysis in Cerebral Infarction (TICI) 2b-3] and 90-day favorable outcome [modified Rankin Scale (mRS) 0-2], any intracerebral hemorrhage, symptomatic intracerebral hemorrhage, procedural complications, and mortality were evaluated. The risk of bias was assessed using the Newcastle-Ottawa Scale and illustrated in the Funnel plot. Heterogeneity was assessed by I ² statistic. Subgroup and sensitivity analyses were also performed. Results: A total of 11 studies accounting 1,517 patients were included. 831 (55%) patients were treated with an antegrade approach and 686 (45%) patients were treated with the retrograde approach. A higher successful reperfusion rate was achieved in retrograde group than that of antegrade group [83.8 vs. 78.0%; odds ratio (OR): 0.63, 95% CI: 0.40-0.99, p = 0.04]. 90-day favorable outcome (mRS 0-2 at 90 days) also showed significantly higher in retrograde group compared with antegrade group (47.3 vs. 40.2%; OR: 0.72, 95% CI: 0.58-0.89, p = 0.002). The incidence of any intracranial hemorrhage (ICH), symptomatic intracranial hemorrhage, 90-day mortality, and other complications did not differ between two groups. Conclusion: In AIS with tandem occlusions, the retrograde approach might achieve a higher successful reperfusion rate and better functional outcome with a comparable safety profile when compared with an antegrade approach. Further prospective controlled studies with more meticulous design and a higher level of evidence are needed to confirm these results. Systematic Review Registration: "PROSPERO" database (CRD 42020199093), https://www.crd.york.ac.uk/PROSPERO/.

Acute Carotid Artery Stenting Versus Balloon Angioplasty for Tandem Occlusions: A Systematic Review and Meta-Analysis

Background Despite thrombectomy having become the standard of care for large-vessel occlusion strokes, acute endovascular management in tandem occlusions, especially of the cervical internal carotid artery lesion, remains uncertain. We aimed to compare efficacy and safety of acute carotid artery stenting to balloon angioplasty alone on treating the cervical lesion in tandem occlusions. Similarly, we aimed to explore those outcomes' associations with technique approaches and use of thrombolysis. Methods and Results We performed a systematic review and meta-analysis to compare functional outcomes (modified Rankin Scale), reperfusion, and symptomatic intracranial hemorrhage and 3-month mortality. We explored the association of first approach (anterograde/retrograde) and use of thrombolysis with those outcomes as well. Two independent reviewers performed the screening, data extraction, and quality assessment. A random-effects model was used for analysis. Thirty-four studies were included in our systematic review and 9 in the meta-analysis. Acute carotid artery stenting was associated with higher odds of modified Rankin Scale score ≤2 (odds ratio [OR], 1.95 [95% CI, 1.24-3.05]) and successful reperfusion (OR, 1.89 [95% CI, 1.26-2.83]), with no differences in mortality or symptomatic intracranial hemorrhage rates. Moreover, a retrograde approach was significantly associated with modified Rankin Scale score ≤2 (OR, 1.72 [95% CI, 1.05-2.83]), and no differences were found on thrombolysis status. Conclusions Carotid artery stenting and a retrograde approach had higher odds of successful reperfusion and good functional outcomes at 3 months than balloon angioplasty and an anterograde approach, respectively, in patients with tandem occlusions. A randomized controlled trial comparing these techniques with structured antithrombotic regimens and safety outcomes will offer definitive guidance in the optimal management of this complex disease.

A clinical perspective on endovascular stroke treatment biomechanics

Acute ischemic stroke (AIS) is caused by blockage of an arterial blood vessel in the brain by a thrombus, which interrupts oxygen supply to the brain parenchyma. The goal of endovascular stroke treatment (mechanical thrombectomy) is to restore blood flow as quickly and completely as possible. There are numerous factors that influence endovascular treatment success. They can be broadly grouped into a) factors related to blood vessels, b) factors related to the thrombus, c) factors related to endovascular treatment technique and tools and d) operator-related factors. While blood vessel and tgthro thrombus-related factors are mostly non-modifiable in the acute setting, operator and technique-related factors can be modified, and extensive research is currently being done to investigate the complex interplay of all these variables, and to optimize the modifiable factors to the maximum possible extent. In this review, we will describe these factors and how they interact with each other in detail, and outline some of their practical implications. We will conclude with a short summary and outlook on future directions for optimizing endovascular treatment success.

Mechanical thrombectomy in acute ischemic stroke with tandem occlusions: impact of extracranial carotid lesion etiology on endovascular management and outcome

OBJECTIVE

Different etiologies of extracranial internal carotid artery steno-occlusive lesions (ECLs) in patients with acute ischemic stroke (AIS) and tandem occlusion (TO) have been pooled together in randomized trials. However, carotid atherosclerosis (CA) and carotid dissection (CD), the two most common ECL etiologies, are distinct nosological entities. The authors aimed to determine if ECL etiology has impacts on the endovascular management and outcome of patients with TO.

METHODS

A multicenter, retrospective study of prospectively collected data was conducted. AIS patients were included who had TO due to internal CA or CD and ipsilateral M1 middle cerebral artery occlusion and underwent endovascular treatment (EVT). Comparative analyses including demographic data, safety, successful recanalization rates, and clinical outcome were performed according to EVT and ECL etiology.

RESULTS

In total, 214 AIS patients with TOs were included (77.6% CA related, 22.4% CD related). Patients treated with a retrograde approach were more often functionally independent at 3 months than patients treated with an antegrade approach (OR 0.6, 95% CI 0.4-0.9). Patients with CD-related TOs achieved 90-day clinical independence more often than patients with CA-related TOs (OR 1.4, 95% CI 1.1-2.0). Emergency stenting use was associated with good 3-month clinical outcome only in patients with CA-related TOs (OR 1.4, 95% CI 1.1-2.1). Symptomatic intracranial hemorrhage (sICH) occurred in 10.7% of patients, without differences associated with ECL etiology.

CONCLUSIONS

ECL etiology impacts both EVT approach and clinical outcome in patients with TOs. Patients with CD-related TO achieved higher 3-month functional independence rates than patients with CA-related TOs. A retrograde approach can be desirable for both CA- and CD-related TOs, and emergency stenting is likely better justified in CA-related TOs.

Acute Stenting and Concomitant Tirofiban Administration for the Endovascular Treatment of Acute Ischemic Stroke Related to Intracranial Artery Dissections: A Single Center Experience and Systematic Review of the Literature

BACKGROUND

Intracranial artery dissection is an uncommon cause of acute ischemic stroke. Although acute stenting of the dissected arterial segment is a therapeutic option, the associated antiplatelet regimen remains a matter of debate.

OBJECTIVES

To evaluate the efficacy and safety of acute intracranial stenting together with concomitant intravenous administration of tirofiban and to perform a systematic review of the literature.

MATERIALS AND METHODS

A single-center, retrospective study of the clinical and radiological records of all patients treated at our center by intracranial stenting in the setting of acute ischemic stroke between January 2010 and December 2020. A systematic review of the literature was conducted according to the PRISMA-P guidelines for relevant publications from January 1976 to December 2020 on intracranial artery dissection treated by stent.

RESULTS

Seven patients with intracranial artery dissections underwent acute stenting with concomitant tirofiban during the study period. Mid-term follow-up showed parent artery patency in 6/7 cases (85.7%). The modified Rankin Score was ≤ 0-2 at 3 months in 5/7 cases (71.4%). The literature review identified 22 patients with intracranial artery dissection treated with acute stenting in association with different antithrombotic therapies. Complete revascularization was obtained in 86.3% of cases with a modified Rankin Score of ≤ 0-2 in 68% of patients at 3-month follow-up.

CONCLUSIONS

Acute intracranial stenting together with intravenous tirofiban administration could be a therapeutic option in patients with intracranial artery dissection and a small ischemic core.

Delayed Contrast-Enhanced MR Angiography for the Assessment of Internal Carotid Bulb Patency in the Context of Acute Ischemic Stroke: An Accuracy, Interrater, and Intrarater Agreement Study

BACKGROUND AND PURPOSE

CTA has shown limited accuracy and reliability in distinguishing tandem occlusions and pseudo-occlusions on initial acute stroke imaging. The utility of early and delayed contrast-enhanced MRA in this setting is unknown. We aimed to assess the accuracy and reliability of early and delayed contrast-enhanced MRA for carotid bulb patency in patients with acute ischemic stroke.

MATERIALS AND METHODS

We retrospectively reviewed patients who had ICA occlusion and underwent thrombectomy with preprocedural early and delayed contrast-enhanced MRA in a single comprehensive stroke center. During 2 sessions, 10 raters independently assessed 32 cases with early contrast-enhanced MRA (with an additional delayed contrast-enhanced MRA sequence during the second reading session). Their judgments were compared with DSA as a reference standard. Accuracy and interrater agreement were measured. Five raters undertook a third reading session to assess intrarater agreement.

RESULTS

Accuracy for the assessment of carotid bulb patency with early contrast-enhanced MRA was limited (69%; 95% CI, 59%-79%), with moderate interrater agreement (κ = 0.42; 95% CI, 0.27-0.55). The second reading with an additional delayed contrast-enhanced MRA sequence improved both accuracy (82%; 95% CI, 73%-91%; P < .001) (raters corrected 43%-77% of incorrect diagnoses with early contrast-enhanced MRA alone; mean = 59%) and interrater agreement (κ = 0.56; 95% CI, 0.41-0.73; P = .07). Intrarater agreement was almost perfect, substantial, and moderate for 3, 1, and 1 raters.

CONCLUSIONS

Early contrast-enhanced MRA has limited accuracy and repeatability for the evaluation of carotid bulb patency in acute ischemic stroke. The additional delayed contrast-enhanced MRA sequence may improve accuracy and reliability.

Learning Curve for Endovascular Treatment of Anterior Circulation Large Vessel Occlusion at a Single Center

Background and purpose: Data concerning the learning curve for endovascular treatment (EVT) of anterior circulation large vessel occlusion are scarce. This study aimed to investigate the relationship between operator experience and the outcome of EVT and to further identify the number of cases needed to acquire the ability to perform successful reperfusion.

Materials and methods: Four hundred and thirty-four patients who underwent EVT by seven operators at a single center from January 2016 to September 2019 were enrolled. Procedural experience was defined by the number of cases performed by each operator. Multivariable backward regression analyses were used to investigate the association between procedural experience and functional independence (defined as a modified Rankin Scale score of 0–2), 90-days mortality, successful reperfusion (defined as a modified Thrombolysis in Cerebral Infarction score of 2b-3), and puncture-to-reperfusion time after adjusting for covariates. A risk-adjusted cumulative sum (RA-CUSUM) chart was utilized to identify the number of caseloads needed to overcome the learning curve effect.

Results: Procedural experience was independently associated with functional independence, 90-days mortality, successful reperfusion, and puncture-to-reperfusion time reduction (per 10-case increment: OR 1.219, 95% CI: 1.079–1.383, P < 0.001; OR 0.847, 95% CI: 0.738–0.968, P = 0.016; OR 1.553, 95% CI: 1.332–1.830, P < 0.001 and β 8.087 min, 95% CI: 6.184–9.991, P < 0.001, respectively). The RA-CUSUM chart indicated that at least 29 cases were required to overcome the learning curve effect.

Conclusions: There was a dose-response relationship between operator case volume and clinical outcome, procedure time, and successful reperfusion. The experience needed for successful EVT was at least 29 cases.

Considerations for Antiplatelet Management of Carotid Stenting in the Setting of Mechanical Thrombectomy: A Delphi Consensus Statement

BACKGROUND AND PURPOSE

There are only few data and lack of consensus regarding antiplatelet management for carotid stent placement in the setting of endovascular stroke treatment. We aimed to develop a consensus-based algorithm for antiplatelet management in acute ischemic stroke patients undergoing endovascular treatment and simultaneous emergent carotid stent placement.

MATERIALS AND METHODS

We performed a literature search and a modified Delphi approach used Web-based questionnaires that were sent in several iterations to an international multidisciplinary panel of 19 neurointerventionalists from 7 countries. The first round included open-ended questions and formed the basis for subsequent rounds, in which closed-ended questions were used. Participants continuously received feedback on the results from previous rounds. Consensus was defined as agreement of ≥70% for binary questions and agreement of ≥50% for questions with >2 answer options. The results of the Delphi process were then summarized in a draft manuscript that was circulated among the panel members for feedback.

RESULTS

A total of 5 Delphi rounds were performed. Panel members preferred a single intravenous aspirin bolus or, in jurisdictions in which intravenous aspirin is not available, a glycoprotein IIb/IIIa receptor inhibitor as intraprocedural antiplatelet regimen and a combination therapy of oral aspirin and a P2Y12 inhibitor in the postprocedural period. There was no consensus on the role of platelet function testing in the postprocedural period.

CONCLUSIONS

More and better data on antiplatelet management for carotid stent placement in the setting of endovascular treatment are urgently needed. Panel members preferred intravenous aspirin or, alternatively, a glycoprotein IIb/IIIa receptor inhibitor as an intraprocedural antiplatelet agent, followed by a dual oral regimen of aspirin and a P2Y12 inhibitor in the postprocedural period.

Efficacy and Safety of Endovascular Treatment in Acute Tandem Carotid Occlusions: Analysis of a Single-Center Cohort

Introduction

Acute ischemic strokes with tandem occlusions, which represent 10–20% of all ischemic strokes, have a particularly poor prognosis. Since emergent treatment of tandem lesions has not been specifically addressed in randomized trials, there is an absence of standardized management.

Objective

We sought to assess the efficacy and safety of acute endovascular treatment in stroke due to tandem occlusions in our center and compare the results with previous reports.

Methods

From a prospective registry we analyzed data of 99 consecutive patients (males: 77.7%, mean age ± SD: 67.5 ± 9.5 years) with stroke due to tandem occlusions who underwent treatment with emergent carotid stenting and intracranial mechanical thrombectomy. Successful recanalization was defined as a TICI score of 2b-3 and a good functional outcome was defined as a modified Rankin scale score ≤2 at 90 days. Symptomatic intracranial hemorrhage (sICH) was considered when associated with worsening on the National Institutes of Health Stroke Scale (≥4 points).

Results

A successful recanalization rate was achieved in 87.8 and 48.5% of the patients had a good functional outcome. sICH and mortality rates were 12.1 and 20.2%, respectively, and 21.2% of the patients received combined treatment with intravenous thrombolysis, which did not affect neither the prognosis nor the recanalization or sICH rates. The time from symptom onset to recanalization and the degree of recanalization were the main factors associated with prognosis and the occurrence of sICH.

Conclusions

Our results suggest that endovascular treatment with emergent carotid stenting and intracranial thrombectomy in patients with acute stroke due to tandem occlusions is an effective and safe procedure.

Acute carotid stenting in patients undergoing thrombectomy: a systematic review and meta-analysis

BACKGROUND

The benefit of acute carotid stenting compared with no acute stenting on clinical outcomes among patients with tandem lesions (TL) undergoing endovascular thrombectomy (EVT) remains unknown.

METHODS

We conducted a a systematic review and meta-analysis of studies comparing acute carotid stenting versus no stenting among TL patients undergoing EVT with regards to 90 day modified Rankin Scale (mRS) score, symptomatic intracerebral hemorrhage (sICH), and mortality. Four reviewers screened citations for eligibility and two assessed retained studies for risk of bias and data extraction. A random effects model was used for the synthesis of aggregated data.

RESULTS

21 studies (n=1635 patients) were identified for the systematic review; 19 were cohort studies, 1 was a post-hoc analysis of an EVT trial, and 1 was a pilot randomized controlled trial. 16 studies were included in the meta-analysis. Acute stenting was associated with a favorable 90 day mRS score: OR 1.43 (95% CI 1.07, 1.91). No significant heterogeneity between studies was found for this outcome (I²=17.0%; χ²=18.07, p=0.26). There were no statistically significant differences for 3 month mortality (OR 0.80 (95% CI 0.50, 1.28)) or sICH (OR 1.41 (95% CI 0.91, 2.19)).

CONCLUSIONS

This meta-analysis suggests that among TL patients undergoing EVT, acute carotid stenting is associated with a greater likelihood of favorable outcome at 90 days compared with no stenting.

Tandem Carotid Lesions in Acute Ischemic Stroke: Mechanisms, Therapeutic Challenges, and Future Directions

Approximately 15% of patients undergoing endovascular thrombectomy for anterior circulation acute ischemic stroke have a tandem lesion, defined as a severe stenosis or occlusion of the cervical internal carotid artery ipsilateral to its intracranial occlusion. Patients with tandem lesions have worse outcomes than patients with isolated intracranial occlusions, but the optimal management of their carotid lesions during endovascular thrombectomy remains controversial. The main options commonly used in current practice include acute stent placement in the carotid lesion versus thrombectomy alone without definitive revascularization of the carotid artery. While treatment decisions for these patients are often complex and strategies vary according to clinical, anatomic, and technical considerations, only results from randomized trials comparing these approaches are likely to strengthen current recommendations and optimize patient care.

Treatment Strategies for Tandem Occlusions in Acute Ischemic Stroke

There is no consensus for the treatment of a tandem occlusion (TO) in a patient presenting with an acute ischemic stroke. In this review article, we will focus on the controversial treatment strategies for TOs. First, we will discuss treatment options including retrograde, antegrade, and delayed approaches. Second, the role of carotid stent placement versus balloon angioplasty for the extracranial occlusion will be presented. Third, anticoagulation and antiplatelet regimens for the treatment TOs published in the literature will be reviewed. Finally, we will discuss whether there is a role for coil occlusion of the cervical carotid artery or whether staged carotid revascularization days after mechanical thrombectomy of the intracranial occlusion maybe appropriate. The optimal treatment strategy of TO has not been established and further larger trials need to be performed to answer the question.

Factors Associated with Failure of Reperfusion in Endovascular Therapy for Acute Ischemic Stroke : A Multicenter Analysis

Aim

In acute large vessel occlusions, endovascular therapy (EVT) achieves flow restoration in the majority of cases; however, EVT fails to achieve sufficient reperfusion in a substantial minority of patients. This study aimed to identify predictors of failed reperfusion.

Methods

In this study 2211 patients from the German Stroke Registry who received EVT for anterior circulation stroke were retrospectively analyzed. Failure of reperfusion was defined as thrombolysis in cerebral infarction (TICI) grades 0/1/2a, and sufficient reperfusion as TICI 2b/3. In 1629 patients with complete datasets, associations between failure of reperfusion and baseline clinical data, comorbidities, location of occlusion, and procedural data were assessed with multiple logistic regression.

Results

Failure of reperfusion occurred in 371 patients (16.8%) and was associated with the following locations of occlusion: cervical internal carotid artery (ICA, adjusted odds ratio, OR 2.01, 95% confidence interval, CI 1.08–3.69), intracranial ICA without carotid T occlusion (adjusted OR 1.79, 95% CI 1.05–2.98), and M2 segment (adjusted OR 1.86, 95% CI 1.21–2.84). Failed reperfusion was also associated with cervical ICA stenosis (>70% stenosis, adjusted OR 2.90, 95% CI 1.69–4.97), stroke of other determined etiology by TOAST (Trial of ORG 10172 in acute stroke treatment) criteria (e.g. nonatherosclerotic vasculopathies, adjusted OR 2.73, 95% CI 1.36–5.39), and treatment given outside the usual working hours (adjusted OR 1.41, 95% CI 1.07–1.86). Successful reperfusion was associated with higher Alberta stroke program early CT score (ASPECTS) on initial imaging (adjusted OR 0.85, 95% CI 0.79–0.92), treatment with the patient under general anesthesia (adjusted OR 0.72, 95% CI 0.54–0.96), and concomitant ICA stenting in patients with ICA stenosis (adjusted OR 0.20, 95% CI 0.11–0.38).

Conclusion

Several factors are associated with failure of reperfusion, most notably occlusions of the proximal ICA and low ASPECTS on admission. Conversely, stent placement in the proximal ICA was associated with reperfusion success.

Electronic supplementary material

The online version of this article (10.1007/s00062-020-00880-8) contains supplementary material, which is available to authorized users.

Acute thromboses and occlusions of dual layer carotid stents in endovascular treatment of tandem occlusions

PURPOSE

To evaluate the occurrence and risk factors of acute in-stent thrombosis or stent occlusion in patients with tandem occlusions receiving intracranial mechanical thrombectomy and emergent extracranial internal carotid artery stenting with a dual layer carotid stent.

METHODS

Multicenter retrospective data collection and analysis of stroke databases of seven comprehensive stroke centers from three European countries.

RESULTS

Overall, 160 patients (mean (SD) age 66 (12) years; 104 men (65%); median (IQR) baseline NIHSS 14 (9-18); IV lysis, n=97 (60.6%)) were treated for a cervical carotid artery occlusion or stenosis using a CASPER stent (MicroVention), and received mechanical thrombectomy for an intracranial occlusion between April 2014 and November 2018. During the procedure or within 72 hours, formation of thrombus and complete occlusion of the CASPER stent was observed in 33/160 (20.8%) and in 12/160 patients (7.5%), respectively. In 25/33 (75.8%) and in 9/12 patients (75%), respectively, this occurred during the procedure. No statistically significant difference was observed between patients with and without thrombus formation with regard to pre-existing long term medication with anticoagulants or intraprocedural administration of heparin, acetylsalicylic acid (ASA), or heparin and ASA. Favorable early neurological outcome was similar in patients with (n=15; 45.5%) and without (n=63; 49.6%) thrombus formation at the CASPER stent.

CONCLUSION

Acute thrombosis or occlusion of CASPER stents in thrombectomy patients receiving emergent extracranial internal carotid artery stenting for tandem occlusions were observed more often during the procedure than within 72 hours of follow-up, were less frequent then previously reported, and showed no impact on early neurological outcome.