Temporal Changes in Care Processes and Outcomes for Endovascular Treatment of Acute Ischemic Stroke: Retrospective Registry Data from Three Korean Centers

Nelonemdaz and Patients With Acute Ischemic Stroke and Mechanical Reperfusion: The RODIN Randomized Clinical Trial

Importance

Nelonemdaz selectively antagonizes the 2B subunit of the N-methyl-d-aspartate glutamate receptor and scavenges free radical species.

Objective

To evaluate whether nelonemdaz enhances the clinical outcomes of patients with acute ischemic stroke undergoing emergent reperfusion therapy.

Design, Setting, and Participants

This multicenter double-blind placebo-controlled randomized phase 3 trial (December 25, 2021, to June 30, 2023, in South Korea) recruited patients with acute ischemic stroke who met the following criteria: National Institutes of Health Stroke Scale score greater than or equal to 8, Alberta Stroke Program Early Computed Tomography score greater than or equal to 4, and endovascular thrombectomy within 12 hours after stroke onset.

Intervention

Patients were assigned in a 1:1 ratio to receive intravenous infusions of nelonemdaz twice a day for 5 days or a matching placebo.

Main Outcomes and Measures

The primary end point was a favorable shift in the modified Rankin scale (mRS) 12 weeks after stroke onset. The secondary end points included various composites of the mRS at 5 and 12 weeks, symptomatic intracranial hemorrhage, and infarct volume. Both intention-to-treat and per-protocol analyses were conducted.

Results

A total of 496 patients were enrolled across 24 Korean stroke centers, of whom 39 dropped out (254 men [55.6%]; mean [SD] age, 72.9 [12.1] years). Baseline characteristics of study participants did not significantly differ. For the primary end point, the distribution of the mRS scores at 12 weeks did not significantly differ between the nelonemdaz and placebo groups (common odds ratio, 0.95; 95% CI, 0.69-1.31). For the secondary end points, a median of mRS at 5 weeks (3 vs 3) and mRS 0 at 12 weeks (18.1% vs 18.2%) did not differ substantially between groups. The occurrence of symptomatic intracranial hemorrhage (2.7% vs 0.9%) and infarct volume within 24 hours of the last trial drug infusion (42 vs 38 mL) did not differ significantly between groups. No serious adverse events were reported regarding the trial drug and placebo.

Conclusions and Relevance

In this randomized clinical trial, nelonemdaz did not meet the primary efficacy end point compared with placebo.

Trial Registration

ClinicalTrials.gov Identifier: NCT05041010.

Intracranial hemorrhage risk in patients with cerebral microbleeds after mechanical thrombectomy for acute ischemic stroke: a systematic review and meta-analysis

Background and purpose intracranial hemorrhage risk in patients with cerebral microbleeds (CMBs) after mechanical thrombectomy for acute ischemic stroke (AIS) was investigated. We searched PubMed and Embase from inception to 29 August 2023 for relevant studies, calculated pooled odds ratio (ORs) of intracerebral hemorrhage (ICH) subtypes in AIS patients with CMB presence, 1-4 or ≥ 5 CMBs versus CMB absence, and with different CMB locations after mechanical thrombectomy. ICH subtypes included any ICH, symptomatic and asymptomatic ICH, hemorrhage outside infarct (including subarachnoid hemorrhage), hemorrhagic infarction, and parenchymal hemorrhage after mechanical thrombectomy. Five eligible studies enrolling 2051 patients were included. No significant association was shown between CMB locations (lobar, deep, infratentorial or mixed) and ICH risk. CMB presence or 1-4 CMBs did not significantly increase the risk of any ICH, symptomatic or asymptomatic ICH, ICH outside infarct, subarachnoid hemorrhage, hemorrhagic infarction, or parenchymal hemorrhage. CMBs ≥ 5 increased the risk of any ICH (OR 2.58, 95% CI 1.16-5.72), parenchymal hemorrhage (OR 3.38, 95% CI 1.43-7.97) and parenchymal hemorrhage-2 (OR 5.33, 2.05-13.86), without increasing hemorrhagic infarction or parenchymal haemorrhage-1 risk. After adjusted for possible confounding factors, increases in CMB burden were associated with hemorrhagic complications but not with symptomatic ICH. In AIS patients who received mechanical thrombectomy, no association was shown between CMB location and ICH risk. ICH risk was not significantly increased by CMB presence or 1-4 CMBs. ICH risk in patients with ≥ 5 CMBs requires further study.

Atrial Fibrillation and Reperfusion Therapy in Acute Ischaemic Stroke Patients: Prevalence and Outcomes-A Comprehensive Systematic Review and Meta-Analysis

Atrial fibrillation (AF) significantly contributes to acute ischaemic stroke (AIS), yet its precise influence on clinical outcomes post-intravenous thrombolysis (IVT) and post-endovascular thrombectomy (EVT) has remained elusive. Furthermore, the overall prevalence of AF in AIS patients undergoing reperfusion therapy has not been clearly determined. Employing random-effects meta-analyses, this research aimed to estimate the pooled prevalence of AF among AIS patients undergoing reperfusion therapy, while also examining the association between AF and clinical outcomes such as functional outcomes, symptomatic intracerebral haemorrhage (sICH) and mortality. Studies comparing AF and non-AF patient groups undergoing reperfusion therapy were identified and included following an extensive database search. Forty-nine studies (n = 66,887) were included. Among IVT patients, the prevalence of AF was 31% (Effect Size [ES] 0.31 [95%CI 0.28-0.35], p < 0.01), while in EVT patients, it reached 42% (ES 0.42 [95%CI 0.38-0.46], p < 0.01), and in bridging therapy (BT) patients, it stood at 36% (ES 0.36 [95%CI 0.28-0.43], p < 0.01). AF was associated with significantly lower odds of favourable 90-day functional outcomes post IVT (Odds Ratio [OR] 0.512 [95%CI 0.376-0.696], p < 0.001), but not post EVT (OR 0.826 [95%CI 0.651-1.049], p = 0.117). Our comprehensive meta-analysis highlights the varying prevalence of AF among different reperfusion therapies and its differential impact on patient outcomes. The highest pooled prevalence of AF was observed in EVT patients, followed by BT and IVT patients. Interestingly, our analysis revealed that AF was significantly associated with poorer clinical outcomes following IVT. Such an association was not observed following EVT.

The Rescue on Reperfusion Damage in Cerebral Infarction by Nelonemdaz (RODIN) Trial: Protocol for a Double-Blinded Clinical Trial of Nelonemdaz in Patients with Hyperacute Ischemic Stroke and Endovascular Thrombectomy

BACKGROUND AND PURPOSE

Nelonemdaz (Neu2000) has both selective antagonism against 2B subunit of N-methyl-D-aspartate receptor and antioxidant activity. This drug provides sufficient evidence of neuroprotection in acute cerebral ischemia/reperfusion models. This phase III trial aims to determine this effect in patients.

DESIGN

The Rescue on Reperfusion Damage in Cerebral Infarction by Nelonemdaz is a multicenter, double-blinded clinical trial. A total of 496 patients will be randomly assigned into the nelonemdaz (a total of 5,250 mg divided by 10 times for 5 days) and placebo groups. Patients will be included if they have an acute ischemic stroke (National Institutes of Health Stroke Scale score ≥8) caused by intracranial large vessel occlusion in the anterior circulation (Alberta Stroke Program Early CT Score ≥4), and if they are expected to undergo endovascular thrombectomy within 12 hours after stroke onset.

ENDPOINTS

The primary endpoint is a favorable shift in the modified Rankin Scale (mRS) score at 90 days after the first dose of drug. The data will be analyzed by the Cochran-Mantel-Haenszel shift test. The secondary endpoints include functional independence (mRS 0-2) at 35 and 90 days, the favorable shift of mRS at 35 days, the proportion of mRS 0 at 35 and 90 days, and the occurrence rates of symptomatic intracranial hemorrhage within 7 days.

CONCLUSION

This trial will clarify the efficacy and safety of nelonemdaz in patients with acute ischemic stroke and endovascular thrombectomy. This study has been registered at ClinicalTrials. gov (NCT05041010).

Nelonemdaz for Patients With Acute Ischemic Stroke Undergoing Endovascular Reperfusion Therapy: A Randomized Phase II Trial

BACKGROUND

Nelonemdaz is a multitarget neuroprotectant that selectively blocks N-methyl-D-aspartate receptors and scavenges free radicals, as proven in preclinical ischemia-reperfusion studies. We aimed to evaluate the safety and efficacy of nelonemdaz in patients with acute ischemic stroke receiving endovascular reperfusion therapy.

METHODS

This phase II randomized trial involved participants with large-artery occlusion in the anterior circulation at baseline who received endovascular reperfusion therapy <8 hours from symptom onset at 7 referral stroke centers in South Korea between October 29, 2016, and June 1, 2020. Two hundred thirteen patients were screened and 209 patients were randomly assigned at a 1:1:1 ratio using a computer-generated randomization system. Patients were divided into 3 groups based on the medication received-placebo, low-dose (2750 mg) nelonemdaz, and high-dose (5250 mg) nelonemdaz. The primary outcome was the proportion of patients with modified Rankin Scale scores of 0-2 at 12 weeks.

RESULTS

Two hundred eight patients were assigned to the placebo (n=70), low-dose (n=71), and high-dose (n=67) groups. The groups had similar baseline characteristics. The primary outcome was achieved in 183 patients, and it did not differ among the groups (33/61 [54.1%], 40/65 [61.5%], and 36/57 [63.2%] patients; P=0.5578). The common odds ratio (90% CI) indicating a favorable shift in the modified Rankin Scale scores at 12 weeks was 1.55 (0.92-2.60) between the placebo and low-dose groups and 1.61 (0.94-2.76) between the placebo and high-dose groups. No serious adverse events were reported.

CONCLUSIONS

The study arms showed no significant difference in the proportion of patients achieving modified Rankin Scale scores of 0-2 at 12 weeks. Nevertheless, nelonemdaz-treated patients showed a favorable tendency toward achieving these scores at 12 weeks, without serious adverse effects. Thus, a large-scale phase III trial is warranted.

REGISTRATION

URL: https://clinicaltrials.gov; Unique identifier: NCT02831088.

Influence of cerebral microbleeds on mechanical thrombectomy outcomes

In ischemic stroke patients undergoing endovascular treatment (EVT), we aimed to test the hypothesis that cerebral microbleeds (CMBs) are associated with clinical outcomes, while estimating the mediating effects of hemorrhagic transformation (HT), small-vessel disease burden (white matter hyperintensities, WMH), and procedural success. From a multicenter EVT registry, patients who underwent pretreatment MR imaging were analyzed. They were trichotomized according to presence of CMBs (none vs. 1–4 vs. ≥ 5). The association between CMB burden and 3-month mRS was evaluated using multivariable ordinal logistic regression, and mediation analyses were conducted to estimate percent mediation. Of 577 patients, CMBs were present in 91 (15.8%); 67 (11.6%) had 1–4 CMBs, and 24 (4.2%) had ≥ 5. Increases in CMBs were associated with hemorrhagic complications (β = 0.27 [0.06–0.047], p = 0.010) in multivariable analysis. The CMB effect on outcome was partially mediated by post-procedural HT degree (percent mediation, 14% [0–42]), WMH (23% [7–57]) and lower rates of successful reperfusion (6% [0–25]). In conclusion, the influence of CMBs on clinical outcomes is mediated by small-vessel disease burden, post-procedural HT, and lower reperfusion rates, listed in order of percent mediation size.

Predictors of Early Neurological Deterioration in Stroke Due to Vertebrobasilar Occlusion

Background and Aims: This study explores the predictors of early neurological deterioration (END) in patients with vertebrobasilar occlusion (VBO) in both primary endovascular therapy (EVT) and medical management (MM) groups. Methods: Patients diagnosed with VBO from 2010 to 2018 were included. Comparative and multivariate analyses were used to identify predictors of all-cause END in the EVT group, and END due to ischemia progression (END-IP) in the MM group. Results: In 174 patients with VBO, 43 had END. In the primary EVT group (N = 66), 17 all-cause END occurred. Distal basilar occlusion (odds ratio (OR), 14.5 [95% confidence interval (CI), 1.4-154.4]) and reperfusion failure (eTICI < 2b67 (OR, 5.0 [95% CI, 1.3-19.9]) were predictive of END in multivariable analysis. In the MM group (N=108), 17 END-IP occurred. Higher systolic blood pressure (SBP) at presentation (per 10 mmHg increase, OR, 1.5 [95% CI, 1.1-2.0]), stroke onset-to-door time <24 h (OR, 5.3 [95% CI, 1.1-2.0]), near-total occlusions (OR, 4.9 [95% CI, 1.2-19.6]), lower posterior circulation-Alberta Stroke Program Early CT scores (OR, 1.6 [95% CI, 1.0-2.5]), and lower BATMAN collateral scores (OR, 1.6 [95% CI, 1.1-2.2]) were predictive of END-IP. Conclusions: In patients with stroke due to VBO, potential predictors of END can be identified. In the primary EVT group, failure to achieve reperfusion and distal basilar occlusion were associated with all-cause END. In the MM group, higher SBP at presentation, onset-to-door time less than 24 h, incomplete occlusions, larger infarct cores, and poorer collaterals were associated with END-IP.

Factors Contributing to an Efficacious Endovascular Treatment for Acute Ischemic Stroke in Asian Population

Although randomized control trials about endovascular treatment (EVT) of emergent large vessel occlusion (LVO) have demonstrated the success of mechanical thrombectomy as the choice of treatment, a wide range of caveats remain unaddressed. Asian patients were rarely included in the trials, thereby raising the question of whether the treatment could be generalized. In addition, there remains a concern on the feasibility of the method with respect to its application against intracranial atherosclerosis (ICAS)-related LVO, frequently observed in the Asian population. It is important to include evidence on ICAS LVO from Asian countries in the future for a comprehensive understanding of LVO etiology. Besides the issues with EVT, prognostic concerns in diabetes patients, acute kidney injury following EVT, neuroprotective management against reperfusion injury, and other peri-EVT issues should be considered in clinical practice. In the current article, we present an in-depth review of the literature that revises information pertaining to such concerns.

Etiological Approach to Understanding Recanalization Failure in Intracranial Large Vessel Occlusion and Thrombectomy: Close to Embolism but Distant From Atherosclerosis

Introduction: In patients with intracranial large vessel occlusion (LVO) who undergo endovascular treatment (EVT), recanalization failure may be related to intracranial atherosclerotic stenosis (ICAS). We evaluated whether the risk factors of recanalization failure could possibly be a marker of ICAS among various types of LVO.

Methods: From a multicenter registry, patients with middle cerebral artery M1 segment occlusions who underwent thrombectomy within 24 h were included. Based on the on-procedure and post-procedure angiographic findings, patients were classified into embolic, ICAS-related, tandem occlusion, and recanalization failure groups. Recanalization failure was defined if the occluded vessel could not be recanalized by stent retrieval, contact aspiration, or local lytics treatment. Risk factors, imaging markers, and EVT methods were compared between groups.

Results: Among 326 patients, 214 were classified as embolism, 76 as ICAS, 16 as tandem, and 20 as recanalization failure. The group with recanalization failure showed higher scores on the National Institutes of Health Stroke Scale (NIHSS) (median, 16.0 vs. 14.5 vs. 14.0 vs. 17.0, p = 0.097), frequent atrial fibrillation (59.3 vs. 18.4 vs. 0 vs. 40.0% p < 0.001), and elevation in erythrocyte sedimentation rate (ESR) (14.5 ± 15.7 vs. 15.0 ± 14.1 vs. 21.2 ± 19.5 vs. 36.0 ± 32.9, p < 0.001) among the groups. The rate of computed tomography angiography-based truncal-type occlusion in recanalization failure group was not as high as that in the ICAS group (8.1 vs. 37.5 vs. 0 vs. 16.7%, p < 0.001). Balloon guide catheters (BGC) were less frequently utilized in the recanalization failure group as compared to their use in the other groups (72.0 vs. 72.4 vs. 62.5 vs. 30.0%, p = 0.001). In the multivariable analysis, initial higher NIHSS [odds ratio (OR), 1.11 95% confidence interval (CI), 1.01–1.22 p = 0.027], higher ESR (OR, 1.03 CI, 1.01–1.05 p = 0.006), and non-use of BGCs (OR, 3.41 CI, 1.14–10.17 p = 0.028) were associated with recanalization failure. In M1 occlusions, the predominant mechanism of recanalization failure was presumed to be embolic in 80% and due to ICAS in 20%.

Conclusion: The analysis of recanalization failures does not suggest an underlying predominant ICAS mechanism. Sufficient utilization of thrombectomy devices and procedures may improve the rates of recanalization.

Predictors and prognoses of Willisian collateral failure during mechanical thrombectomy

During mechanical thrombectomy in the anterior cerebral circulation, thrombus embolization resulting in Willisian collateral failure may lead to critical stroke outcomes due to a shutdown of leptomeningeal collaterals. We hypothesized that the outcomes of dynamic Willisian collateral failure (DWF), induced during mechanical thrombectomy, would be associated with grave outcomes. We evaluated this hypothesis in consecutive patients, between January 2011 and May 2016, who underwent mechanical thrombectomy for anterior circulation occlusions, with an onset-to-puncture of 24 h. Patients with initial Willisian collateral failure (IWF) were identified first, with remaining patients classified into the DWF and Willisian collateral sparing (WCS) groups. Comparative and multivariable analyses were performed to predict grave outcomes (3-month modified Rankin Scale score of 5–6). Among 567 patients, 37 were in the IWF group, 38 in the DWF group, and 492 in the WCS group. Compared to the WCS and DWF groups, the IWF group had a higher baseline National Institute of Health Stroke Scale score and lower Alberta Stroke Program Early CT Score. The prevalence of grave outcomes was similarly high in the IWF (48.6%) and DWF (47.4%) groups, but lower in the WCS group (22.0%; p < 0.001). IWF and DWF were independent risk factors for a grave outcome.

The Clinical Usefulness of Targeted Temperature Management in Acute Ischemic Stroke with Malignant Trait After Endovascular Thrombectomy

BACKGROUND/OBJECTIVE

Targeted temperature management (TTM) may be more beneficial after endovascular treatment (EVT) in patients with a large ischemic core. Therefore, we assessed the usefulness of TTM for such patients from a multicenter endovascular registry.

METHODS

Anterior circulation stroke patients who underwent endovascular recanalization were included; acute ischemic stroke with malignant traits was designated as (1) baseline Alberta Stroke Program Early CT Score (ASPECTS) below 6 and (2) diffusion-weighted imaging (DWI) lesion volume measurement (> 82 ml) or National Institutes of Health Stroke Scale score > 20 and item Ia > 0. TTM (34.5 °C) was maintained for at least 48 h.

RESULTS

We evaluated baseline demographics, risk factors, EVT parameters, and clinical outcomes between the TTM and non-TTM groups. Among the 548 patients, the TTM group (n = 91) significantly had a lower baseline ASPECTS (p < 0.001) and a higher DWI volume (p < 0.001) than the non-TTM group (n = 457). TTM group had a lower prevalence of favorable outcome (0-2 of modified Rankin Scale at 3 months; p = 0.008) than the non-TTM group. In a subgroup analysis of malignant trait patients (n = 80), TTM patients (n = 28) had more favorable outcome (32.1% vs. 7.7% p = 0.009) and less hemorrhagic transformation (none vs. any hemorrhage, p = 0.007) than non-TTM patients (n = 52). After adjusting for potential outcome predictors, TTM (odds ratio [OR] 4.63; confidence interval [CI] 1.20-17.89; p = 0.026) and hypertension (OR 0.18; CI 0.04-0.74; p = 0.018) were found to be independent determinants.

CONCLUSIONS

Our data suggest that TTM attenuates impending hemorrhagic transformation and leads to favorable clinical outcomes in EVT patients with malignant trait.

Direct Stenting of Intracranial Atherosclerosis-related Acute Large Vessel Occlusion

PURPOSE

Endovascular reperfusion therapy (ERT) in patients with intracranial atherosclerosis (ICAS)-related acute large vessel occlusion (ALVO) may require different strategies based on the underlying culprit plaque lesion. This study investigated the effectiveness and safety of direct stent placement in ICAS-related ALVO compared with initially attempted mechanical thrombectomy (MT) with or without rescue treatment.

METHODS

Direct stenting for ICAS-related ALVO was performed in 30 consecutive patients between January 1, 2012, and December 31, 2018. As a control for comparison, MT with or without rescue stenting for patients with ICAS-related ALVO was performed in 73 consecutive patients during the same period. Clinical outcomes were assessed by measuring modified Rankin Scale (mRS) at 90 days.

RESULTS

Patients who underwent direct stenting and those who underwent MT with or without rescue stenting showed no significant differences in baseline characteristics. There was a higher proportion of patients with mRS 0-2 at 90 days in the direct stenting group than in the MT with or without rescue stenting group [24 (80.0%) vs. 34 (46.6%); p = 0.004]. Successful recanalization to modified thrombolysis in cerebral infarction category 2b or 3 was achieved in 93.3% of patients who underwent direct stenting, and in 90.4% of patients who underwent MT with or without rescue stenting.

CONCLUSION

Direct stenting is an effective and safe option for ICAS-related ALVO. Further studies are needed to confirm that endovascular treatments are effective and safe in patients with ALVO and underlying ICAS.

Local tirofiban infusion for remnant stenosis in large vessel occlusion: tirofiban ASSIST study

BACKGROUND

Compared with embolic occlusions, intracranial atherosclerotic stenosis (ICAS)-related large vessel occlusions (LVOs) often require rescue treatment following mechanical thrombectomy (MT). Herein, we hypothesized that local tirofiban infusion can be effective and safe for remnant stenosis in LVO during endovascular treatment and can improve clinical outcomes.

METHODS

This observational multicenter registry study (January 2011 to February 2016) included patients with ICAS who underwent endovascular treatment for LVO within 24 h after stroke onset. An underlying fixed focal stenosis at the occlusion site observed on cerebral angiography during and after MT was retrospectively determined as a surrogate marker of ICAS. Procedural and clinical outcomes were compared between the tirofiban and non-tirofiban groups.

RESULTS

Of 118 patients, 59 received local tirofiban infusion. Compared to the non-tirofiban group, patients were older (non-tirofiban group versus tirofiban group; median, 63 years vs. 71 years, p = 0.015) and the onset-to-puncture time was longer (median, 275 min vs. 395 min, p = 0.036) in the tirofiban group. The median percent of residual stenosis prior to rescue treatment tended to be higher in the tirofiban group (80 [71-86] vs. 83 [79-90], p = 0.056). Final reperfusion success (modified Treatment In Cerebral Ischemic 2b-3) was more frequent (42.4%vs. 86.4%, p = 0.016) and post-procedure parenchymal hematoma type 2 and/or thick subarachnoid hemorrhages were less frequent (15.3%vs. 5.1%, p = 0.068) in the tirofiban group. The frequency of favorable outcomes 3 months after endovascular treatment (modified Rankin Scale 0-2) was significantly higher in the tirofiban group (32.2% vs. 52.5%, p = 0.025), and tirofiban administration was an independent predictor of favorable outcomes (odds ratio, 2.991; 95% confidence interval, 1.011-8.848; p = 0.048).

CONCLUSIONS

Local tirofiban infusion can be a feasible adjuvant treatment option for patients with ICAS-LVO.

Predicting Endovascular Treatment Outcomes in Acute Vertebrobasilar Artery Occlusion: A Model to Aid Patient Selection from the ASIAN KR Registry

Background The decision to perform endovascular treatment (EVT) for stroke related to vertebrobasilar occlusion (VBO) remains controversial. Purpose To identify preprocedural predictors of good outcomes and to develop a model to aid patient selection for VBO. Materials and Methods For this retrospective study using a Korean multicenter registry, a predictive model for good outcomes (modified Rankin scale score, 0-2) was generated based on a derivation sample of patients with VBO (January 2011-February 2016). Preprocedural parameters, including onset-to-puncture time, infarct volume, occlusion type as a surrogate marker of intracranial atherosclerotic stenosis-related occlusion or embolic occlusion (truncal-type occlusion vs branching site occlusion), and collateral status, were analyzed. Continuous variables were dichotomized based on receiver operating characteristic analysis. Multiple logistic regression analysis was performed to generate a predictive model. The model was internally validated with the bootstrap method and was externally validated with a single-center sample (April 2016-December 2018). Results A predictive model was generated from 71 patients (mean age, 67 years ± 11 [standard deviation]; 41 [58%] men) and was externally validated in 32 patients (mean age, 72 years ± 13; 19 [59%] men). The composite of initial DW imaging volume of less than 10 mL (odds ratio [OR], 19.3; 95% confidence interval [CI]: 3.0, 126.4; P = .002), onset-to-puncture time of less than 8 hours (OR, 8.7; 95% CI: 1.8, 42.0; P = .007), and branching-site occlusion (OR, 6.1; 95% CI: 1.5, 26.0; P = .01) could be used to predict good outcomes, with a median area under the receiver operating characteristic curve of 0.86 (interquartile range [IQR], 0.77-0.95; bootstrap optimism-corrected C statistic, 0.837) in the derivation sample and 0.78 (IQR, 0.62-0.95) in the validation sample. Results failed to show an association between collateral status and outcome (P = .67). Conclusion When selecting patients with vertebrobasilar occlusion for endovascular treatment, the combination of onset-to-puncture time of less than 8 hours, initial infarct volume of less than 10 mL, and presence of branching-site occlusions is indicative of a good outcome. © RSNA, 2020 Online supplemental material is available for this article.

Optimal Multiphase Computed Tomographic Angiography-based Infarct Core Estimations for Acute Ischemic Stroke

We evaluated the best methods for predicting various infarct core thresholds for endovascular treatment of ischemic stroke using parameters obtained by multiphase computed tomographic angiography (mCTA). Consecutive patients evaluated for endovascular treatment who concomitantly underwent mCTA and stroke magnetic resonance imaging (MRI) were analyzed. The ability of CTA-based collaterals (single-phase [sCTAc] and multiphase [mCTAc]) and ASPECTS or their combined interpretation for the selection of patients with cores of <31 ml and <70 ml, and ≥100 ml, were compared. In the total 142 patients, the combined interpretation of collateral scores and ASPECTS score indicated significant added benefit for the prediction of smaller infarct volume thresholds (<31 ml) compared to ASPECTS alone. Selection of cases that satisfied both sCTAc 3–5 and ASPECTS 6–10 had the optimal predictive capability and inter-rater reliability. While the combined interpretation did not provide a significant added benefit for the prediction of larger infarct volume thresholds, sCTAc 0–2 and mCTAc 0–2 performed as well as ASPECTS 0–5 in prediction of core volumes ≥100 ml with better inter-rater reliability. sCTA and mCTA can improve the selection of patients for EVT by more accurately predicting lower infarct core volume cutoffs. When excluding patients with large infarct cores, they can improve inter-rater reliability.

Clinical Impact of Intracerebral Hemorrhage after Hyperacute Extracranial Stenting in Patients with Ischemic Stroke

PURPOSE

Emergent intracranial occlusions causing acute ischemic stroke are often related to extracranial atherosclerotic stenosis. This study aimed to investigate the association between post-procedure intracerebral hemorrhage (ICH) and emergent extracranial artery stenting and assess their effects on clinical outcomes in patients with acute ischemic stroke.

MATERIALS AND METHODS

We retrospectively analyzed patients undergoing hyperacute endovascular treatment for cervicocephalic vascular occlusion in three Korean hospitals between January 2011 and February 2016. Patients who had extracranial artery involvement and were treated from 24 hours of symptom onset to puncture were included in this study, and they were divided into the extracranial stenting (ES) and non-ES groups. Any type of petechial hemorrhages and parenchymal hematoma was defined as ICH for the current study.

RESULTS

In total, 76 patients were included in this study. Among them, 56 patients underwent ES, and 20 patients did not. Baseline characteristics, risk factors, laboratory data, treatment methods, successful reperfusion rates, and baseline stenotic degrees of extracranial internal carotid artery did not differ between these two groups. However, atrial fibrillation was more frequent in patients without than with ES (P=0.002), and post-procedure ICH was more frequent in patients with than without ES (P=0.035). Logistic regression models revealed that ES was independently associated with post-procedure ICH (odds ratio [OR], 7.807; 95% confidence interval [CI], 1.213-50.248; P=0.031), and ICH was independently associated with poor clinical outcomes (OR, 0.202; 95% CI, 0.054-0.759; P=0.018); however, ES itself was not associated with clinical outcomes (OR, 0.530; 95% CI, 0.117-2.395; P=0.409). Notably, ICH and ES had interaction for predicting good outcomes (P=0.041).

CONCLUSION

Post-procedure ICH was associated with ES and poor clinical outcomes. Therefore, ES should be cautiously considered in patients with hyperacute stroke.

CTA-Based Truncal-Type Occlusion Is Best Matched With Postprocedural Fixed Focal Stenosis in Vertebrobasilar Occlusions

Background: Differentiation of embolic and atherosclerotic occlusions is difficult prior to endovascular treatment (EVT) of acute ischemic stroke due to intracranial large artery occlusions. CTA-determined occlusion type has been reported to be associated with a negative cardiac embolic source and stent retriever failure, a potential of intracranial atherosclerosis (ICAS)-related occlusions. In this study, we evaluated the agreement between preprocedural identification of CTA-determined truncal-type occlusion (TTO) and postprocedural evaluation of underlying fixed focal stenosis (FFS) in the occlusion site.

Methods: Patients who underwent intracranial EVT for acute ischemic stroke within 24 h of onset and who had baseline CTA were identified from a multicenter registry collected between January 2011 and May 2016. Preprocedural occlusion type was classified as TTO (target artery bifurcation saved) or branching-site occlusion (bifurcation involved) on CTA. As for postprocedural identification, FFS was evaluated by stepwise analyses of procedural and postprocedural angiographies. The agreement between TTO and FFS was evaluated in respective intracranial vascular beds. Receiver operating characteristics analyses were also performed.

Results: A total of 509 patients were included [intracranial internal carotid artery (ICA): 193, middle cerebral artery (MCA) M1: 256, and vertebrobasilar artery (VBA): 60]. In preprocedural identification, 33 (17.1%), 41 (16.0%), and 29 patients (48.3%) had TTOs, respectively. TTOs had good agreement with angiographic FFS in M1 (positive predictive value: 63.4%, negative predictive value: 83.2%, likelihood ratio: 5.42, P_multivariate < 0.001) and VBA (72.4%, 96.8%, and 4.54, respectively, P_multivariate = 0.004), but not in intracranial ICA occlusions (P_multivariate = 0.358). The area under the receiver operating characteristics curve was the largest for VBA (0.872, p < 0.001), followed by MCA M1 (0.671, p < 0.001), and intracranial ICA (0.551, p = 0.465).

Conclusions: Agreement between preprocedural TTO and postprocedural FFS, both of which are surrogate markers for ICAS-related occlusions, is highest for VBA, followed by MCA M1 occlusions. There is no significant association in intracranial ICA.

Solitaire Thrombectomy for Acute Stroke Due to Intracranial Atherosclerosis-Related Occlusion: ROSE ASSIST Study

Background: Solitaire, a representative stent retriever, has shown high performance in removing embolic clots. However, its reperfusion potential in intracranial atherosclerotic stenosis (ICAS)-related occlusions has rarely been reported. In this ROSE ASSIST study, we hypothesized that Solitaire device is as effective and safe for removing in situ thrombi in ICAS-related occlusions as it is for removal of embolic occlusions.

Methods: Data from ASIAN KR, an observational multicenter registry (n = 720) enrolling patients who have undergone endovascular treatment for acute cervicocephalic artery occlusions, were retrospectively reviewed. Through blinded evaluations, occlusions were classified as ICAS-related (significant fixed focal stenosis observed at the occlusion site during endovascular treatment) or embolic (no or minimal stenosis observed). Among patients treated within 720 min after stroke onset, those who undertook Solitaire thrombectomy and whose underlying etiology was ICAS-related or embolic were included. The primary endpoint was immediate successful reperfusion (modified Treatment In Cerebral Ischemia 2b−3) after Solitaire stent retrieval. The safety endpoint included intracerebral hemorrhagic transformation and subarachnoid hemorrhage. Comparative analyses were performed between embolic and ICAS-related occlusions with 2:1 propensity score matching.

Results: In total, 303 patients (embolic, 228; ICAS-related, 75) were included in the analyses. As for the primary endpoint, the immediate successful reperfusion rate following Solitaire thrombectomy did not differ between the two etiologic groups after propensity score matching (73.1% embolic vs. 65.8% ICAS-related, p = 0.261). The final successful reperfusion grade was also similar in the two groups (79.3 vs. 72.0%, p = 0.219). The grades and frequencies of intracerebral hemorrhagic transformation and subarachnoid hemorrhage did not differ between groups (p = 0.134 and p = 0.269, respectively).

Conclusions: The immediate reperfusion performance in terms of thrombus removal of Solitaire thrombectomy for ICAS-related occlusions was similar to that for embolic occlusions.

Prognosis of Acute Intracranial Atherosclerosis-Related Occlusion after Endovascular Treatment

Background and Purpose

Little is known about prognosis after endovascular therapy (EVT) for acute large artery occlusion (LAO) caused by underlying intracranial atherosclerotic stenosis (ICAS). Therefore, we investigated the prognosis following EVT according to the underlying etiology of LAO.

Methods

Patients from the Acute Stroke due to Intracranial Atherosclerotic occlusion and Neurointervention-Korean Retrospective (ASIAN KR) registry (n=720) were included if their occlusion was in the intracranial anterior circulation and their onset-to-puncture time was <24 hours. Occlusion was classified according to etiology as follows: no significant stenosis after recanalization (Embolic group), and fixed significant focal stenosis in the occlusion site with flow impairment or re-occlusion observed during EVT (ICAS group). Patients were excluded when significant extracranial carotid lesions existed, and when the intracranial occlusion was intractable to EVT so that the etiology was undetermined. The effect of angiographic etiologic classification on outcomes was evaluated using multivariable analysis that was adjusted for potential confounders.

Results

Among eligible patients (n=520), 421 and 99 were classified in the Embolic and ICAS groups, respectively. Patients in the Embolic and ICAS groups had similar successful reperfusion rates with EVT (79.6% vs. 76.8%, P=0.537) and 3-month functional independence (54.5% vs. 45.5%, P=0.104). In multivariable analysis, ICAS-related occlusion (odds ratio, 0.495; 95% confidence interval, 0.269 to 0.913; P=0.024) showed poorer 3-month functional independence compared to embolic occlusion.

Conclusions

After EVT, patients with acute ICAS-related occlusion have relatively poor functional outcomes compared to those with embolic occlusion. Novel strategies need to be developed to improve EVT outcomes for ICAS occlusion.

Impact of varying levels of hyperglycemia on clinicoradiographic outcomes after endovascular reperfusion treatment

We evaluated the effects of admission hyperglycemia with different cut-off levels on 3-month outcomes, infarct growth, and hemorrhagic transformation in acute stroke patients with large artery occlusion of anterior circulation who received endovascular treatment (EVT). Between January 2011 and May 2016, patients that underwent EVT with pre-procedural and post-procedural diffusion-weighted imaging were identified from a multicenter registry. Normoglycemia was defined as a glucose level ≤ 110 mg/dL, moderate hyperglycemia as >110 and ≤170 mg/dL, and overt hyperglycemia as >170 mg/dL. Its effects on poor outcomes (3-month modified Rankin Scale score 3-6), infarct growth, and parenchymal hematoma type 2 were analyzed. Of 720 patients encountered, 341 patients were eligible. There was a statistically significant difference in glycated hemoglobin levels between the normoglycemia/moderate hyperglycemia and overt hyperglycemia groups (p < 0.001). Moderate hyperglycemia (odds ratio 2.37 [95% confidence interval 1.26-4.45], p = 0.007) and overt hyperglycemia (2.84 [1.19-6.81], p = 0.019) were associated with poor outcomes. Post-procedural infarct volumes were significantly greater in hyperglycemic patients (p_adjusted = 0.003). Only overt hyperglycemia (9.28 [1.66-51.88], p = 0.011) was associated with parenchymal hematoma type 2. Overall hyperglycemia was associated with poor outcomes and infarct growth, whereas overt hyperglycemia was associated with parenchymal hematoma type 2.