Angiographical Identification of Intracranial, Atherosclerosis-Related, Large Vessel Occlusion in Endovascular Treatment

Pre-treatment radiological factors associated with poor functional outcome in an Asian cohort of large vessel occlusion acute ischemic stroke patients undergoing mechanical thrombectomy

Background and aims

Endovascular thrombectomy (EVT) is the current standard of care for large vessel occlusion (LVO) acute ischemic stroke (AIS); however, up to two-thirds of EVT patients have poor functional outcomes despite successful reperfusion. Many radiological markers have been studied as predictive biomarkers for patient outcomes in AIS. This study seeks to determine which clinico-radiological factors are associated with outcomes of interest to aid selection of patients for EVT for LVO AIS.

Methods

A retrospective study of patients who underwent EVT from 2016 to 2020 was performed. Data on various radiological variables, such as anatomical parameters, clot characteristics, collateral status, and infarct size, were collected alongside traditional demographic and clinical variables. Univariate and multivariate analysis was performed for the primary outcomes of functional independence at 3 months post-stroke (modified Rankin Scale 0-2) and secondary outcomes of in-hospital mortality and symptomatic intracranial hemorrhage.

Results

The study cohort comprised 325 consecutive patients with anterior circulation LVO AIS (54.5% male) with a median age of 68 years (interquartile range 57-76). The median NIHSS was 19. Age, hypertension, hyperlipidaemia, National Institutes of Health Stroke Scale (NIHSS), Alberta mCTA score, ASPECTS, clot length, thrombus HU and mTICI score and the angle between ICA and CCA were associated with functional outcomes at 3 months on univariate analysis. On multivariate analysis, age, Alberta mCTA collaterals and NIHSS were significantly associated with functional outcomes, while ASPECTS approached significance.

Conclusion

Among the many proposed radiological markers for patients in the hyperacute setting undergoing EVT, the existing well-validated clinico-radiological measures remain strongly associated with functional status.

Balloon angioplasty as first-choice recanalization strategy for intracranial atherosclerosis-related emergent large vessel occlusion with small clot burden

PURPOSE

The optimal primary recanalization strategy for intracranial atherosclerosis-related emergent large vessel occlusion (ICAS-ELVO) remains controversial. We aimed to explore the safety and efficacy of balloon angioplasty as the first-choice recanalization strategy for ICAS-ELVO with small clot burden.

METHODS

Consecutive ICAS-ELVO patients presenting with microcatheter "first-pass effect" during endovascular treatment (EVT) were retrospectively analyzed. Patients were divided into preferred balloon angioplasty (PBA) and preferred mechanical thrombectomy (PMT) groups based on the first-choice recanalization strategy. The reperfusion and clinical outcomes between the two groups were compared.

RESULTS

Seventy-six patients with ICAS-ELVO involving the microcatheter "first-pass effect" during EVT were enrolled. Compared with patients in the PMT group, those in the PBA group were associated with (i) a higher rate of first-pass recanalization (54.0% vs. 28.9%, p = .010) and complete reperfusion (expanded thrombolysis in cerebral ischemia ≥ 2c; 76.0% vs. 53.8%, p = .049), (ii) shorter puncture-to-recanalization time (49.5 min vs. 89.0 min, p < .001), (iii) lower operation costs (¥48,499.5 vs. ¥ 99,086.0, p < .001), and (iv) better 90-day functional outcomes (modified Rankin scale:0-1; 44.0% vs. 19.2%, p = .032). Logistic regression analysis revealed that balloon angioplasty as the first-choice recanalization strategy was an independent predictor of 90-day excellent functional outcomes for ICAS-ELVO patients with microcatheter "first-pass effect" (adjusted odds ratio = 6.01, 95% confidence interval: 1.15-31.51, p = .034).

CONCLUSION

Direct balloon angioplasty potentially improves 90-day functional outcomes for ICAS-ELVO patients with small clot burden, and may be a more appropriate first-choice recanalization strategy than mechanical thrombectomy for these patients.

Association of Early Longitudinal Changes in the Neutrophil-to-Lymphocyte Ratio With Adverse Clinical Outcomes in Acute Ischemic Stroke Patients After Endovascular Treatment

BACKGROUND

We aim to elucidate the contribution of early dynamic changes in the neutrophil-to-lymphocyte ratio (NLR) to poor clinical outcomes in acute ischemic stroke patients after endovascular treatment (EVT).

METHODS

Acute ischemic stroke patients who underwent EVT were consecutively recruited from January 2019 to July 2022. Blood cell counts were sampled at admission and at following 24 hours after EVT. Clinical outcome measures included 3-month functional dependence (modified Rankin scale of 3-6), symptomatic intracranial hemorrhage, and mortality at 7 days and 30 days. Multinomial logistic regressions were used to evaluate the association of changes in the NLR with unfavorable outcomes.

RESULTS

A total of 590 patients were included in the final analysis. The multinomial logistic model indicated that the increasing changes in the NLR after EVT was an independent factor for poor outcomes; the adjusted odds ratio was 1.06 (95% confidence interval [CI] 1.03-1.10; P < 0.001) at poor 3-month functional outcomes, 1.07 (95% CI 1.04-1.10; P < 0.001) at symptomatic intracranial hemorrhage, 1.08 (95% CI 1.05-1.12; P < 0.001) at mortality at 7 days, and 1.04 (95% CI 1.02-1.07; P = 0.001) at mortality at 30 days. Areas under the curve of changes in NLR to discriminate adverse outcomes were 0.725, 0.687, 0.664, and 0.659, respectively. The optimal cutoff values were 5.77 (56.6% sensitivity, 81.0% specificity), 6.92 (60.0% sensitivity, 77.0% specificity), 8.64 (51.0% sensitivity, 82.0% specificity), and 8.64 (48.7% sensitivity, 83.0% specificity), respectively.

CONCLUSIONS

The NLR in acute ischemic stroke patients increased remarkably independent of successful reperfusion. Elevated changes in the NLR might predict malignant hemorrhagic transformation, adverse functional outcomes, and short-term mortality.

Prediction of Intracranial Atherosclerotic Disease-Related Large-Vessel Occlusion Stroke on the Basis of Novel Cerebral Blood Volume Parameters

BACKGROUND

Mechanical thrombectomy is an effective treatment method for large-vessel occlusion stroke (LVOS); however, it has limited efficacy for intracranial atherosclerotic disease (ICAD)-related LVOS. We investigated the use of cerebral blood volume (CBV) maps for identifying ICAD as the underlying cause of LVOS before the initiation of endovascular treatment (EVT).

METHODS AND RESULTS

We reviewed clinical and imaging data from patients who presented with LVOS and underwent endovascular treatment between January 2011 and May 2021. The CBV patterns were analyzed to identify an increase in CBV within the hypoperfused area and estimate infarct patterns within the area of decreased CBV. Comparisons were made between the patients with an increase in CBV and those without, and among the estimated infarct patterns: territorial, cortical wedge, basal ganglia-only, subcortical, and normal CBV. Overall, 243 patients were included. CBV increase in the hypoperfused area was observed in 23.5% of patients. A significantly higher proportion of ICAD was observed in those with increased CBV than in those without (56.4% versus 19.8%; P<0.001). Regarding the estimated infarct patterns on the CBV, ICAD was most frequently observed in the normal CBV group (territorial, 14.9%; cortical wedge, 10.0%; basal ganglia-only, 43.8%; subcortical, 35.7%; normal, 61.7%). CBV parameters, including "an increase in CBV," "normal CBV infarct pattern," and "an increase in CBV or normal CBV infarct pattern composite," were independently associated with ICAD.

CONCLUSIONS

An increased CBV or normal CBV pattern may be associated with ICAD LVOS on the pretreatment perfusion imaging.

Intracranial atherosclerotic disease: current management strategies

A stroke due to underlying intracranial large artery occlusion, which is atherosclerotic in nature, is known as intracranial atherosclerotic disease (ICAD). It is important to recognize that ischaemic stroke due to ICAD differs from extracranial disease and other stroke aetiologies and requires a nuanced approach. It is a significant cause of stroke worldwide, and severe symptomatic ICAD can present challenges from a therapeutic standpoint, including recurrent ischaemic stroke despite optimal management. Furthermore, exploring the underlying pathophysiological mechanisms responsible for the disease may be necessary while considering treatment options. This narrative review aims to provide an all-encompassing overview of this disease. Epidemiology and clinical pathophysiology will be explored in detail. The findings of large clinical trials will serve as a guide to finding the most optimized management strategies. Another critical question that arises is the treatment of acute ischaemic stroke due to large vessel occlusion with underlying intracranial atherosclerosis, is the treatment and clinical diagnosis the same as for other aetiologies of stroke (i.e. extracranial disease and nonvalvular atrial fibrillation)? Consequently, secondary prevention of patients with ischaemic stroke or transient ischaemic attack will be divided into medical therapy, risk factor control, and endovascular and surgical treatment options.

Rescue Intracranial Balloon Angioplasty with or without Stent Placement in Acute Strokes with Intracranial Atherosclerotic Disease

BACKGROUND

Optimal management of acute ischemic stroke (AIS) secondary to intracranial atherosclerotic disease (ICAD) refractory to conventional mechanical thrombectomy remains unclear. We aimed to investigate the clinical outcome of patients undergoing rescue intracranial balloon angioplasty with or without stent placement in the setting of AIS in our institution.

METHODS

This is a retrospective single-arm observational study to evaluate the efficacy and safety of rescue balloon angioplasty with or without stent placement in emergent large vessel occlusion (EVLO) strokes with underlying ICAD. We included all patients undergoing such rescue intervention within 24 hours of AIS presentation with EVLO between 2017 and 2021. We further evaluated stent or vessel reocclusion.

RESULTS

Of 20 patients undergoing rescue intervention, 3 cases achieved adequate recanalization of artery using balloon angioplasty alone. Seventeen patients required stent placement. Fourteen (70%) procedures resulted in National Institutes of Health Stroke Scale improvement in postprocedure and upon discharge. Among 6 (30%) procedures with worsening neurological measures, 3 had reoccluded stent 24-48 hours after procedure, 2 had symptomatic hemorrhagic conversion, and 1 had perforator occlusion. Nine patients (45%) had favorable functional outcome (modified Rankin Scale ≤2) at discharge, unchanged or improved at 3-month follow-up. The median modified Rankin Scale score was 4 (Interquartile range: 1.75-4) at discharge, improving to 3 (Interquartile range: 0-4) at 3-month follow-up. Two patients (10%) died during hospital stay.

CONCLUSIONS

Rescue angioplasty with or without stenting can lead to significant clinical improvement in patients with ICAD presenting with ELVO and refractory to thrombectomy; however, this procedure is associated with a high rate of morbidity in acute setting.

Safety and Efficacy of Prasugrel Administration in Emergent Endovascular Treatment for Intracranial Atherosclerotic Disease

Objective

Intracranial atherosclerosis disease (ICAD) is one of the most common causes of acute ischemic stroke. In endovascular treatment (EVT) for acute large vessel occlusion stroke-related ICAD, reocclusion of the recanalized artery due to in situ thrombosis is problematic. In this study, the safety and efficacy of prasugrel administration to avoid reocclusion of emergent EVT for ICAD was investigated.

Methods

All consecutive emergent EVTs for ICAD between September 2019 and December 2022 were included in this study. The procedures were divided into two groups as receiving periprocedural prasugrel (PSG group) or not (non-PSG group). Target vessel patency on follow-up, postprocedural intracranial hemorrhage (ICH), and clinical outcome were compared between PSG and non-PSG groups.

Results

A total of 27 procedures were included in this analysis. Nineteen target vessels were patent on follow-up and eight were non-patent. Fifteen patients received prasugrel (18.75 mg: 11 cases, 11.25 mg: 4 cases), and twelve patients did not receive prasugrel. The target vessel patency rate was better in the PSG group vs. non-PSG group (100% vs. 33.3%, respectively; p = 0.0002). The postprocedural ICH rate was not different between the groups (PSG: 40.0% vs. non-PSG: 25.0%; p = 0.68), and all ICHs were asymptomatic. Good clinical outcome (modified Rankin Scale score of 0 to 3 at discharge) was more frequent in the PSG group than that in the non-PSG group (66.7% vs. 16.7%, respectively; p = 0.019).

Conclusion

Prasugrel administration was significantly associated with target vessel patency and good clinical outcome after emergent EVT for ICAD without increasing the symptomatic ICH rate. Prasugrel administration might be safe and effective to avoid reocclusion during and after emergent EVT for ICAD.

Endovascular Treatment for Acute Large Vessel Occlusion Due to Underlying Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is one of the most common causes of acute ischemic stroke worldwide. Patients with acute large vessel occlusion due to underlying ICAD (ICAD-LVO) often do not achieve successful recanalization when undergoing mechanical thrombectomy (MT) alone, requiring rescue treatment, including intra-arterial thrombolysis, balloon angioplasty, and stenting. Therefore, early detection of ICAD-LVO before the procedure is important to enable physicians to select the optimal treatment strategy for ICAD-LVO to improve clinical outcomes. Early diagnosis of ICAD-LVO is challenging in the absence of consensus diagnostic criteria on noninvasive imaging and early digital subtraction angiography. In this review, we summarize the clinical and diagnostic criteria, prediction of ICAD-LVO prior to the procedure, and EVT strategy of ICAD-LVO and provide recommendations according to the current literature.

Large Vessel Occlusion Stroke due to Intracranial Atherosclerotic Disease: Identification, Medical and Interventional Treatment, and Outcomes

Large vessel occlusion stroke due to underlying intracranial atherosclerotic disease (ICAD-LVO) is prevalent in 10 to 30% of LVOs depending on patient factors such as vascular risk factors, race and ethnicity, and age. Patients with ICAD-LVO derive similar functional outcome benefit from endovascular thrombectomy as other mechanisms of LVO, but up to half of ICAD-LVO patients reocclude after revascularization. Therefore, early identification and treatment planning for ICAD-LVO are important given the unique considerations before, during, and after endovascular thrombectomy. In this review of ICAD-LVO, we propose a multistep approach to ICAD-LVO identification, pretreatment and endovascular thrombectomy considerations, adjunctive medications, and medical management. There have been no large-scale randomized controlled trials dedicated to studying ICAD-LVO, therefore this review focuses on observational studies.

Angioplasty, stenting, or both - rescue maneuvers and reperfusion after endovascular therapy for intracranial atherosclerosis-related occlusion

PURPOSE

Data concerning reperfusion strategies of intracranial atherosclerosis-related occlusion (ICARO) and clinico-angiographic outcomes remain scarce, particularly in Caucasians. We aim to compare the reperfusion rate and functional outcome between reperfusion strategies in the setting of the ICARO.

METHODS

Retrospective analysis of prospectively maintained endovascular thrombectomy (EVT) registries at three high-volume stroke centers were retrospectively analyzed for consecutive ICARO patients from January 2015 to December 2019. We defined ICARO as any fixed high-degree (> 70%) focal narrowing or stenosis of any degree with a perpetual tendency for reocclusion. We categorized reperfusion strategies into four groups: EVT [group 1], balloon angioplasty [(BAp), group 2], placement of self-expandable stents [(SES), group 3], and BAp combined with implantation of SES; or direct placement of balloon mounted stents (BMS) [(BAp-SES/BMS), group 4]. We evaluated the association with the successful reperfusion [mTICI 2b - 3] and favorable outcome [mRS 0-2] with logistic regression analysis.

RESULTS

Out of 2550 EVT, 124 patients (median age, 70 (61-80) years; 76 men) with ICARO and 130 reperfusion attempts [36 EVT, 38 BAp, 17 SES, and 39 BAp + SES/BMS] were analyzed. SES implantation showed the highest frequency of post-procedural symptomatic intracranial hemorrhage [(18%, 3/17), p = .03]; however, we observed no significant differences in the mortality rate. Overall, we achieved successful reperfusion in 71% (92/130) and favorable outcomes in 42% (52/124) of the patients. BAp + SES/BMS was the only independent predictor of the final successful reperfusion [aOR, 4.488 (95% CI, 1.364-14.773); p = .01], which was significantly associated with the 90-day favorable outcome [aOR, 10.837 (95% CI, 3.609-32.541); p =  < .001] after adjustment for confounding variables between the reperfusion strategies.

CONCLUSION

Among patients with ICARO, the rescue angioplasty stenting effectively contributed to higher odds of successful reperfusion with no increased risk for intracranial hemorrhage.

Effect of Truncal-Type Occlusion Based on Multiphase or Single-Phase Computed Tomographic Angiography in Predicting Intracranial Atherosclerotic Stenosis-Related Acute Middle Cerebral Artery Occlusion

OBJECTIVE

To investigate whether truncal-type occlusion based on multiphase computed tomographic angiography (mpCTA) was more effective for predicting intracranial atherosclerotic stenosis-related occlusion (ICAS-O) than occlusion type based on single-phase computed tomographic angiography (spCTA) in patients with acute ischemic stroke with large-vessel occlusion (AIS-LVO) in the middle cerebral artery (MCA).

METHODS

Data were retrospectively collected from 72 patients with AIS-LVO in the MCA between January 2018 and December 2019. The occlusion types included truncal-type and branching-site occlusions. The association between ICAS-O and occlusion type based on the 2 computed tomographic angiography patterns was analyzed, and receiver operating characteristic curves were plotted for assessment. The areas under the curve were compared to determine the difference between the predictive powers of truncal-type occlusion based on mpCTA and spCTA.

RESULTS

Among the 72 patients, 16 were classified as having ICAS-O and 56 as having embolisms. In univariate analysis, truncal-type occlusion was significantly associated with ICAS-O (P < 0.001 for mpCTA and P = 0.001 for spCTA). After multivariable analysis, truncal-type occlusion based on both mpCTA and spCTA remained independently associated with ICAS-O (P = 0.002 for mpCTA and P = 0.029 for spCTA). The areas under the curve were 0.821 for mpCTA and 0.683 for spCTA; this difference was statistically significant (P = 0.024).

CONCLUSIONS

In patients with AIS-LVO in the MCA, truncal-type occlusion based on mpCTA enables more accurate detection of ICAS-O than that based on spCTA.

Outcomes Following Mechanical Thrombectomy in Different Etiological Subtypes of Acute Basilar Artery Occlusion : Stroke Etiology and Outcome after EVT in BAO

BACKGROUND AND PURPOSE

Vertebrobasilar occlusion stroke (VBOS) is innately associated with high morbimortality despite advances in endovascular thrombectomy (EVT). Nonetheless, notable outcome dissimilarities exist between angiographically categorized stroke subtypes. We aim to evaluate potential differences concerning clinical angiographic outcomes among etiological subtypes of VBOS based on the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria.

METHODS

We retrospectively reviewed prospective EVT databases at two tertiary care stroke centers for consecutive patients with VBOS who had preinterventional MRI and underwent EVT from January 2015 to December 2019. We identified three groups: large artery atherosclerosis (LAA), cardioembolic stroke (CES), and embolic stroke of undetermined source (ESUS). The primary endpoints were the rates of poor outcome (identified as 90-day modified Rankin scale score of 3-6) and mortality, while the secondary endpoint included the rates of incomplete reperfusion (identified as modified treatment in cerebral infarction scale mTICI 0-2b), and periprocedural symptomatic intracranial hemorrhage. We evaluated the association between the etiology and clinical angiographic outcomes through stepwise logistic regression analysis.

RESULTS

Out of 1823 patients, 139 (91 men; median age, 69 (61-76) years) with VBOS were qualified for the final analysis with incidence as follows: LAA (41%, n = 57), CES (35%, n = 48), and ESUS (24%, n = 34). Overall, incomplete reperfusion was realized in 41% (57/139) of the patients, a poor outcome in 65% (90/139), and mortality in 40% (55/139). Longer puncture to reperfusion interval (aOR 1.0182 [95% CI: 1.008-1.029]; p < 0.001) and utilization of combined aspiration-retriever technique (aOR 0.1998 [95% CI: 0.066-0.604]; p = 0.004) were associated with a greater likelihood of incomplete reperfusion (mTICI 0-2b) irrespective of the stroke etiology. After adjustment for confounding factors in the regression analysis, ESUS was an independent predictor of poor outcome (aOR 5.315 [95% CI: 1.646-17.163]; p = 0.005) and mortality (aOR 4.667 [95% CI: 1.883-11.564]; p < 0.001) at 90 days following EVT.

CONCLUSION

The functional outcome following EVT for VBOS might depend on stroke etiology. According to our results, ESUS seems to be associated with the worst outcome, which needs further investigation to tailor the appropriate therapeutic plan.

A comparison between different endovascular treatment strategies for acute large vessel occlusion due to intracranial artery atherosclerosis: data from ANGEL-ACT Registry

PURPOSE

The aim of our study is to compare the characteristics and clinical outcomes among the different endovascular treatment (EVT) strategies for large vessel occlusion underlying intracranial atherosclerosis (ICAS-LVO) in a recent nationwide registry.

METHODS

Patients with isolated ICAS-LVO were enrolled in our analysis and were categorized into three groups: first-line mechanical thrombectomy (MT) with rescue angioplasty and/or stenting (MT + RS), direct angioplasty and/or stenting without thrombectomy (DA), and MT alone. Baseline and periprocedural characteristics, successful recanalization, and 90-day functional outcomes were compared.

RESULTS

Of 396 patients with isolated ICAS-LVO in our study, successful recanalization was achieved in 94.5%, 100%, and 90.9% of patients in the MT + RS, DA, and MT groups, respectively. The 90-day functional independence in the three groups was 50.8%, 59.0%, and 45.1%. The main efficacy and safety outcomes showed no significant differences among the groups. First-pass recanalization (FPR) was more observed in the MT group (43.4%), the recanalization rate per attempt in the MT group gradually decreased until the fourth attempt, and further maneuvers showed recanalization rates of ≈0% per attempt. MT + RS (adjusted odds ratio [aOR] 0.10, p < 0.0001) and DA (aOR 0.18, p = 0.0013) were associated with lower FPR rate than MT alone in the multivariable logistic regression.

CONCLUSIONS

The technical feasibility and favorable outcomes of several EVT strategies for ICAS-LVO were established in our study. First-line MT with a bailout angioplasty is a reasonable option for ICAS-LVO, and DA is an effective option for the cases when ICAS-LVO is strongly suspected before EVT procedure.

Endovascular Treatment of Large Vessel Occlusion Strokes Due to Intracranial Atherosclerotic Disease

Mechanical thrombectomy (MT) has become the gold-standard for patients with acute large vessel occlusion strokes (LVOS). MT is highly effective in the treatment of embolic occlusions; however, underlying intracranial atherosclerotic disease (ICAD) represents a therapeutic challenge, often requiring pharmacological and/or mechanical rescue treatment. Glycoprotein IIb/IIIa inhibitors have been suggested as the best initial approach, if reperfusion can be achieved after thrombectomy, with angioplasty and/or stenting being reserved for the more refractory cases. In this review, we focus on the therapeutic considerations surrounding the endovascular treatment of ICAD-related acute LVOS.

Endovascular Treatment for Acute Basilar Artery Occlusion: A Comparison of Arteriosclerotic, Embolic and Tandem Lesions

PURPOSE

To evaluate the safety and efficacy of endovascular treatment (EVT) for patients with acute ischemic stroke (AIS) due to intracranial atherosclerosis-related basilar artery occlusion (ICAS-related BAO) by comparison with embolic and tandem occlusion.

METHODS

We retrospectively reviewed consecutive patients with AIS due to BAO who underwent EVT. Patients were assigned to the ICAS-related group and embolic group, and tandem group based on the etiology. Baseline data, procedural details, and clinical outcomes were compared between the three groups.

RESULTS

A total of 100 patients (ICAS-related group: 31; embolic group: 41; tandem group: 28) were included. No significant difference was observed in the successful reperfusion (mTICI 2b or 3), but the procedural time differed significantly (60 min vs. 43 min vs. 60 min, P = 0.010). There were no differences in the different intracranial hemorrhage grades among the three groups (P = 0.134). After adjusting for baseline differences, there was no significant difference in pairwise comparisons regarding favorable outcome (mRS 0-2), moderate outcome (mRS 0-3), and mortality.

CONCLUSIONS

Endovascular treatment for patients with acute ICAS-related BAO had equal efficacy and safety compared with embolic BAO and tandem BAO. Primary endovascular treatment and rescue modalities were effective treatments for acute ICAS-related BAO.

Combination of Rescue Stenting and Antiplatelet Infusion Improved Outcomes for Acute Intracranial Atherosclerosis-Related Large-Vessel Occlusion

Background and Purpose: Intracranial atherosclerosis-related large-vessel occlusion caused by in situ thrombo-occlusion (ICAS-LVO) has been regarded an important reason for refractoriness to mechanical thrombectomy (MT). To achieve better outcomes for ICAS-LVO, different endovascular strategies should be explored. We aimed to investigate an optimal endovascular strategy for ICAS-LVO.

Methods: We retrospectively reviewed three prospective registries of acute stroke underwent endovascular treatment. Among them, patients with ICAS-LVO were assigned to four groups based on their endovascular strategy: (1) MT alone, (2) rescue intracranial stenting after MT failure (MT-RS), (3) glycoprotein IIb/IIIa inhibitor infusion after MT failure (MT-GPI), and (4) a combination of MT-RS and MT-GPI (MT-RS+GPI). Baseline characteristics and outcomes were compared among the groups. To evaluate whether the endovascular strategy resulted in favorable outcome, multivariable analysis was also performed.

Results: A total of 184 patients with ICAS-LVO were included. Twenty-four patients (13.0%) were treated with MT alone, 25 (13.6%) with MT-RS, 84 (45.7%) with MT-GPI, and 51 (27.7%) with MT-RS+GPI. The MT-RS+GPI group showed the highest recanalization efficiency (98.0%). Frequency of patent arteries on follow-up (98.0%, p < 0.001) and favorable outcome (84.3%, p < 0.001) were higher in the MT-RS+GPI group than other groups. The MT-RS+GPI strategy remained an independent factor for favorable outcome (odds ratio, 20.4; 95% confidence interval, 1.97–211.4; p = 0.012).

Conclusion: Endovascular strategy was significantly associated with procedural and clinical outcomes in acute stroke by ICAS-LVO. A combination of RS and GPI infusion might be an optimal rescue modality when frontline MT fails.

Quantitative Assessment of Hyperdense Sign Measured by Hounsfield Units is Associated with Unsuccessful Mechanical Thrombectomy

PURPOSE

Despite advancement in mechanical thrombectomy (MT) techniques, 10-30% of MT for large vessel occlusions (LVO) are unsuccessful. Current prediction models fail to address the association between patient-specific factors and reperfusion. We aimed to evaluate objective, easily reproducible, admission clinical and radiological biomarkers that predict unsuccessful MT.

METHODS

We analyzed consecutive anterior LVO MT patients at two comprehensive stroke centers. The primary outcome was unsuccessful reperfusion defined by a modified thrombolysis in cerebral infarction (mTICI) score of 0-2a. We quantitatively assessed the hyperdense vessel sign by measuring Hounsfield units (HU) on admission computed tomography (CT). Receiver operating characteristic (ROC) curves were plotted to estimate the predictive value of quantitative hyperdense middle cerebral artery (MCA) measurements (delta and ratio) and of the final model for mTICI scores. We performed multivariable logistic regression to analyze associations with outcomes.

RESULTS

Out of 348 patients 87 had unsuccessful MT. Smoking, difficult arch, vessel tortuosity, vessel calcification, diminutive vessels, truncal M1 occlusion, delta HU and HU ratio were significantly associated with unsuccessful MT in the univariate analysis. When we fitted two separate multivariate models including all significant variables and a HU measurement; delta HU <6 (odds ratio, OR = 2.07, 95% confidence intervals, CI 1.09-3.92) and HU ratio ≤1.1 (OR = 2.003, 95% CI 1.05-3.81) were independently associated with failed MT after adjustment for smoking, diminutive vessels, vessel tortuosity, and difficult arch. The area under the curve AUC<9 of the final model was 0.717.

CONCLUSION

Novel radiological biomarkers on CT, CT angiography (CTA) and digital subtraction angiography (DSA) may help identify patients refractory to standard MT and prepare interventionalists for using additional alternative methods. Quantitative assessment of HU (delta and ratio) may be important in developing objective prediction tools for unsuccessful MT.

Prediction of Infarct Growth and Neurological Deterioration in Patients with Vertebrobasilar Artery Occlusions

We aimed to identify predictors of infarct growth and neurological deterioration (ND) in vertebrobasilar occlusions (VBOs) with a focus on clinical-core mismatch. From 2010 to 2018, VBO patients were selected from a university hospital registry. In total, 138 VBO patients were included. In these patients, a posterior circulation Alberta Stroke Program Early CT score (PC-ASPECTS) less than 6 was associated with futile outcome. Within patients with feasible cores, a decrease in PC-ASPECTS score of 2 or more on follow-up imaging was classified as infarct growth and could be predicted by a National Institutes of Health Stroke Scale (NIHSS) mental status subset of 1 or higher (odds ratio (OR): 3.34, 95% confidence interval (CI) (1.19-9.38), p = 0.022). Among the 73 patients who did not undergo reperfusion therapy, 13 patients experienced ND (increase in discharge NIHSS score of 4 or more compared to the initial presentation). Incomplete occlusion (vs. complete occlusion, OR 6.17, 95% CI (1.11-34.25), p = 0.037), poorer collateral status (BATMAN score, OR: 1.91, 95% CI (1.17-3.48), p = 0.009), and larger infarct cores (PC-ASPECTS, OR: 1.96, 95% CI (1.11-3.48), p = 0.021) were predictive of ND. In patients with VBO, an initial PC-ASPECTS of 6 or more, but with a decrease in the mental status subset of 1 or more can predict infarct growth, and may be used as a criterion for clinical-core mismatch. ND in VBO patients presenting with milder symptoms can be predicted by incomplete occlusion, poor collaterals, and larger infarct cores.

Direct angioplasty for acute ischemic stroke due to intracranial atherosclerotic stenosis-related large vessel occlusion

BACKGROUND

Intracranial artery atherosclerotic stenosis (ICAS) is among the causes of intracranial large artery occlusion (LVO). The optimal treatment strategy for patients with ischemic stroke due to ICAS-related LVO remains unclear. In this retrospective case series, we discussed our experience with direct angioplasty as frontline therapy for ICAS-related LVO.

METHODS

We extracted data for patients who had a known pre-existing ICAS and undergone direct angioplasty as frontline therapy for ICAS-related LVO in the anterior circulation at our institution between January 2019 and December 2019. We analysed procedural details, the degree of reperfusion, functional outcomes, and complications. Successful reperfusion was defined as a modified Treatment in Cerebral Ischemia (mTICI) score of 2 b - 3. Functional outcomes at 90 days were assessed using modified Rankin Scale (mRS) scores (good outcome: mRS of 0-2).

RESULTS

We analysed data for five patients (mean age: 51.6 ± 11 years). The mean time from symptom onset to recanalization was 371 ± 38.6 min. Occlusions involved the first segment of the middle cerebral artery in four patients and the intracranial internal carotid artery in one patient. Successful reperfusion was achieved in four (80%) patients. The remaining patient (20%) underwent intracranial stenting as rescue therapy, achieving a final mTICI of 2a. No re-occlusion was observed on follow-up images. Four patients (80%) achieved good outcomes at 90 days. There were no cases of symptomatic intracranial hemorrhage, although asymptomatic intracranial haemorrhage was observed in one patient.

CONCLUSION

Direct angioplasty may represent an alternative treatment strategy in patients with acute ischemic stroke due to known ICAS-related LVO.

Immediate effects of first-line thrombectomy devices for intracranial atherosclerosis-related occlusion: stent retriever versus contact aspiration

BACKGROUND

Although stent retriever (SR) is recommended as a frontline device of endovascular treatment (EVT) for embolic large artery occlusion causing acute ischemic stroke, contact aspiration (CA) device showed similar efficacy in the recent trials. However, the efficacy of the both devices as first-line therapy for intracranial atherosclerotic stenosis (ICAS)-related large vessel occlusion has not yet been established. Therefore, we compared the immediate effects and final outcomes of SR and CA as first-line devices for treating ICAS-related occlusions.

METHODS

We retrospectively analyzed the data of patients who underwent EVT for acute ischemic stroke from the registry of three Korean hospitals. Patients with ICAS-related occlusion who were treated within 24 h of onset of the symptoms were included. We investigated immediate reperfusion performance, immediate safety outcomes, and 3-month clinical outcomes for the two first-line devices.

RESULTS

Of the 720 registered patients, 111 were eligible for this study. Forty-nine patients (44.1%) used SR and 62 (55.9%) used CA as the first-line device. Achieving successful reperfusion immediately after first-line thrombectomy was more frequent in the SR group than that in the CA group (77.6% vs. 43.5%, p = 0.001), with fewer additional rescue treatments (12.2% vs. 59.7%, p < 0.001). The incidence of iatrogenic dissection or rupture was lower in the SR group than that in the CA group (8.2% vs. 29.0%, p = 0.012). After additional rescue treatments, however, the final successful reperfusion rate did not differ between the two groups (SR 87.8% vs. CA 77.4%, p = 0.247), and there was no significant difference in the 3-month good outcomes (modified Rankin Scale, p = 0.524).

CONCLUSIONS

First-line SR thrombectomy showed higher immediate reperfusion and less vessel injury for ICAS-related occlusions than CA. However, there was no significant difference in the final reperfusion status or 3-month outcomes from additional rescue treatments.

Improving the Clinical Outcome in Stroke Patients Receiving Thrombolytic or Endovascular Treatment in Korea: from the SECRET Study

We investigated whether there was an annual change in outcomes in patients who received the thrombolytic therapy or endovascular treatment (EVT) in Korea. This analysis was performed using data from a nationwide multicenter registry for exploring the selection criteria of patients who would benefit from reperfusion therapies in Korea. We compared the annual changes in the modified Rankin scale (mRS) at discharge and after 90 days and the achievement of successful recanalization from 2012 to 2017. We also investigated the determinants of favorable functional outcomes. Among 1230 included patients, the improvement of functional outcome at discharge after reperfusion therapy was noted as the calendar year increased (p < 0.001). The proportion of patients who were discharged to home significantly increased (from 45.6% in 2012 to 58.5% in 2017) (p < 0.001). The successful recanalization rate increased over time from 78.6% in 2012 to 85.1% in 2017 (p = 0.006). Time from door to initiation of reperfusion therapy decreased over the years (p < 0.05). These secular trends of improvements were also observed in 1203 patients with available mRS data at 90 days (p < 0.05). Functional outcome was associated with the calendar year, age, initial stroke severity, diabetes, preadmission disability, intervals from door to reperfusion therapy, and achievement of successful recanalization. This study demonstrated the secular trends of improvement in functional outcome and successful recanalization rate in patients who received reperfusion therapy in Korea.

Effects of first pass recanalization on outcomes of contact aspiration thrombectomy

BACKGROUND

First pass recanalization (FPR, defined as achieving a modified Thrombolysis in Cerebral Ischemia (mTICI) grade 2c/3 with a single pass of a thrombectomy device) effect has not yet been evaluated in contact aspiration thrombectomy (CAT). We evaluated FPR effect on clinical outcomes and FPR predictors in CAT.

METHODS

All consecutive patients who underwent frontline CAT for anterior circulation large vessel occlusion with recanalization (mTICI 2b-3) were identified from registries at six stroke centers. The patients were dichotomized into FPR and non-FPR groups. Clinical features and outcomes were compared between the groups. Multivariate analyses were performed to determine whether FPR was independently associated with clinical outcomes and to identify predictors of FPR.

RESULTS

Of the 429 patients who underwent frontline CAT, recanalization was successful in 344 patients (80.2%; mean age 68.7±11.0 years; M:F ratio 179:165). The FPR group had a higher rate of good outcome (modified Rankin Scale score 0-2) than the non-FPR group. Furthermore, the good outcome rate was higher in the FPR group than in patients who achieved mTICI 2c/3 with multiple passes or rescue treatment. FPR (OR 2.587; 95% CI 1.237 to 5.413) remained independently associated with good outcomes, in addition to age, baseline National Institute Health Stroke Scale, and coronary artery disease. The use of a balloon guide catheter (OR 3.071; 95% CI 1.699 to 5.550) was the only predictor of FPR.

CONCLUSIONS

Patients in the FPR group had better clinical outcomes than the non-FPR group in CAT. FPR was independently associated with a good outcome. The use of a balloon guide catheter was the only predictor of FPR.