Recommendations on angiographic revascularization grading standards for acute ischemic stroke: a consensus statement

Endovascular Therapy for Basilar Artery Occlusion in Sudden Onset to Maximal Deficit Ischemic Events

BACKGROUND

The presence of sudden onset to maximal deficit (SOTMD) in patients with acute basilar artery occlusion often results in more severe outcomes. However, the effect of endovascular therapy on SOTMD and whether the outcome is affected by onset-to-puncture time remain unclear.

METHODS AND RESULTS

This retrospective analysis was conducted using data from the prospective BASILAR (Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry). Consecutive patients with basilar artery occlusion receiving endovascular therapy were dichotomized into SOTMD and non-SOTMD cohorts. The primary outcomes included a favorable outcome (modified Rankin scale 0-3), recanalization, and mortality at 90 days. The outcomes of patients with SOTMD were analyzed using multivariable logistic regression. In the multivariate analysis, a favorable outcome was similar between the two cohorts (odds ratio [OR], 0.88 [95% CI, 0.58-1.34]; P=0.5), although the mortality of patients with SOTMD was higher than that of patients with non-SOTMD (OR, 1.67 [95% CI, 1.14-2.44]; P=0.008). The probability of mortality increased from 40.0% at 1 hour to 70.0% at 6 hours in the SOTMD cohort, and favorable outcomes of patients with non-SOTMD declined from 38.0% at 1 hour to 18.0% at 8 hours.

CONCLUSIONS

No significant difference was observed in favorable outcomes between the SOTMD and non-SOTMD groups, although mortality was higher in the SOTMD cohort. The patients with SOTMD had a stronger time dependence for endovascular therapy in terms of mortality, while the time dependency regarding favorable outcome in the NSOTMD group was even higher.

REGISTRATION

URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1800014759.

Pretreatment CT perfusion collateral parameters correlate with penumbra salvage in middle cerebral artery occlusion

BACKGROUND AND PURPOSE

Acute ischemic stroke due to large vessel occlusion (AIS-LVO) is a major cause of functional dependence. Collateral status (CS) is an important determinant of functional outcomes. Pretreatment CT perfusion (CTP) parameters serve as reliable surrogates of CS. Penumbra Salvage Index (PSI) is another parameter predictive of functional outcomes in AIS-LVO. The aim of this study is to assess the relationship of pretreatment CTP parameters with PSI.

METHODS

In this prospectively collected, retrospectively reviewed multicenter analysis, inclusion criteria were as follows: (1) CT angiography confirmed middle cerebral artery (MCA) M1-segment and proximal M2-segment occlusion from 9/1/2017 to 9/22/2022; (2) diagnostic CTP; and (3) available diagnostic Magnetic resonance Imaging (MRI) diffusion-weighted images. Pearson correlation analysis was performed to assess the association between cerebral blood volume (CBV) index and hypoperfusion intensity ratio (HIR) with PSI. p value ≤.05 was considered statistically significant.

RESULTS

In total, 131 patients (n = 86, M1 and n = 45, proximal M2 occlusion) met our inclusion criteria. CBV index showed a modest positive correlation with PSI (r = 0.34, p<.001) in patients with proximal MCA occlusion. Similar trends were noted in subgroup analysis of patients with M1 occlusion, and proximal M2 occlusion. Whereas, HIR did not have a strong trend or correlation with PSI.

CONCLUSION

CBV index correlates with PSI, whereas HIR does not. Future studies are needed to expand our understanding of the adjunct role of CBV index with other similar pretreatment CTP-based markers in clinical evaluation and decision-making in patients with MCA occlusion.

Incidence, severity and impact on functional outcome of persistent hypoperfusion despite large-vessel recanalization, a potential marker of impaired microvascular reperfusion: Systematic review of the clinical literature

The reported incidence of persistent hypoperfusion despite complete recanalization as surrogate for impaired microvascular reperfusion (IMR) has varied widely among clinical studies, possibly due to differences in i) definition of complete recanalization, with only recent Thrombolysis in Cerebral Infarction (TICI) grading schemes allowing distinction between complete (TICI3) and partial recanalization with distal occlusions (TICI2c); ii) operational definition of IMR; and iii) consideration of potential alternative causes for hypoperfusion, notably carotid stenosis, re-occlusion and post-thrombectomy hemorrhage. We performed a systematic review to identify clinical studies that carried out brain perfusion imaging within 72 hrs post-thrombectomy for anterior circulation stroke and reported hypoperfusion rates separately for TICI3 and TICI2c grades. Authors were contacted if this data was missing. We identified eight eligible articles, altogether reporting 636 patients. The incidence of IMR after complete recanalization (i.e., TICI3) tended to decrease with the number of considered alternative causes of hypoperfusion: range 12.5-42.9%, 0-31.6% and 0-9.1% in articles that considered none, two or all three causes, respectively. No study reported the impact of IMR on functional outcome separately for TICI-3 patients. Based on this systematic review, IMR in true complete recanalization appears relatively rare, and reported incidence highly depends on definition used and consideration of confounding factors.

No-reflow phenomenon in stroke patients: A systematic literature review and meta-analysis of clinical data

BACKGROUND

The no-reflow phenomenon refers to the absence of microvascular reperfusion despite macrovascular reperfusion.

AIM

The aim of this analysis was to summarize the available clinical evidence on no-reflow in patients with acute ischemic stroke.

METHODS

A systematic literature review and a meta-analysis of clinical data on definition, rates, and impact of the no-reflow phenomenon after reperfusion therapy was carried out. A predefined research strategy was formulated according to the Population, Intervention, Comparison, and Outcome (PICO) model and was used to screen for articles in PubMed, MEDLINE, and Embase up to 8 September 2022. Whenever possible, quantitative data were summarized using a random-effects model.

RESULTS

Thirteen studies with a total of 719 patients were included in the final analysis. Most studies (n = 10/13) used variations of the Thrombolysis in Cerebral Infarction scale to evaluate macrovascular reperfusion, whereas microvascular reperfusion and no-reflow were mostly assessed on perfusion maps (n = 9/13). In one-third of stroke patients with successful macrovascular reperfusion (29%, 95% confidence interval (CI), 21-37%), the no-reflow phenomenon was observed. Pooled analysis showed that no-reflow was consistently associated with reduced rates of functional independence (odds ratio (OR), 0.21, 95% CI, 0.15-0.31).

CONCLUSION

The definition of no-reflow varied substantially across studies, but it appears to be a common phenomenon. Some of the no-reflow cases may simply represent remaining vessel occlusions, and it remains unclear whether no-reflow is an epiphenomenon of the infarcted parenchyma or causes infarction. Future studies should focus on standardizing the definition of no-reflow with more consistent definitions of successful macrovascular reperfusion and experimental set-ups that could detect the causality of the observed findings.

Comparison between different referral strategies for acute ischemic stroke patients in a hub-spoke emergency stroke network: a real-world experience in south-east Lazio

AIM

To describe different referral strategies for acute ischemic stroke (AIS) patients in a Hub-Spoke emergency stroke network with their incidence, time metrics and related outcomes.

METHODS

Referral paradigms were defined as follows: primary transfer to the comprehensive stroke center (CSC) from a remote region, called mothership (MS); secondary transfer to the CSC from a primary stroke center where intravenous thrombolysis was available, called drip and ship (DS); secondary transfer to the CSC from a community hospital where no reperfusion therapy was available, called ship and drip (SD); primary transfer to the CSC from its catchment area, called direct CSC (dCSC).

RESULTS

Among 517 anterior circulation AIS patients treated with mechanical thrombectomy between 2015 and 2020, 16.6% of them were SD, in addition to the well-known referral paradigms of MS (21.8%) and DS (18.1%). This rate grew to 30% when only patients whose place of onset was outside the CSC catchment area were considered. In the SD group, onset to CSC and onset to groin were significantly longer (178±80 min vs. 102±60 min, p<0.001, and 277±77 min vs. 211±61 min, p<0.001, respectively), and the risk of any intracranial hemorrhage (ICH) was significantly higher (OR: 2.514; 95%CI: 1.18-5.35, p=0.017) compared to MS.

CONCLUSION

In this hub-spoke stroke network, a high proportion of SD paradigm was found, which was associated with longer times to treatment and higher rates of any ICH. A closer cooperation between hospital stroke physicians, national health system staff, and paramedics is warranted to identify the most appropriate referral strategy for each patient.

Association of Chinese visceral adiposity index with clinical outcome in patients after endovascular thrombectomy

BACKGROUND AND PURPOSE

The Chinese Visceral Adiposity Index (CVAI) is a reliable indicator of visceral adiposity dysfunction in the Chinese population. We aimed to evaluate the association between CVAI and clinical outcome in Chinese ischemic stroke patients who received endovascular thrombectomy (EVT).

METHODS

This study retrospectively included patients with large vessel occlusive stroke receiving EVT treatment in 2 China stroke centers. Baseline CVAI was calculated after admission. Patients with a modified Rankin scale score ≥ 3 at 3 months after ischemic stroke were defined as poor outcome. Binary multivariate logistic regression models were utilized to explore the association between CVAI and the risk of 90-day unfavorable outcome.

RESULTS

A total of 453 patients (mean age, 70.4  ± 12.1 years; 280 male) were included. During the 90-day follow-up, 236 (52.1 %) patients experienced poor outcome. After multivariable adjustment for potential confounders, increasing CVAI was associated with an increased risk of 90-day poor outcome (odds ratios, per-standard deviation increase: 1.521; 95 % confidence interval, 1.127-2.052; P = 0.006). Similar significant results were observed when the CVAI was analyzed as a categorical variable. Furthermore, the multiple-adjusted spline regression model showed an inverted J-shape association between CVAI and risk of unfavorable outcome (P = 0.048 for non-linearity).

CONCLUSIONS

This study demonstrated that CVAI is positively correlated with 90-day poor outcome in Chinese ischemic stroke patients after EVT.

"The microcatheter contrast injection technique": A novel technique to detect the proximal end of a thrombus in mechanical thrombectomy

Background: An aspiration catheter needs to attach to a thrombus in order to achieve first-pass recanalization by mechanical thrombectomy (MT) for acute ischemic stroke (AIS), particularly that using a direct aspiration first pass technique. The meniscus sign, which is defined as meniscoid contrast opacification indicating the proximal edge of a thrombus, has been suggested to contribute to successful recanalization. In some cases, the meniscus sign is not detected following an injection of contrast medium through a guiding catheter. To precisely identify the location of a thrombus, we use "the microcatheter contrast injection (MCI) technique," which accurately shows the proximal edge of a thrombus. We herein introduce this novel technique and discuss its efficacy in MT. Methods: In cases without the meniscus sign, a microcatheter was advanced to the distal end of contrast opacification, and contrast medium was injected through the microcatheter to detect the meniscus sign. An aspiration catheter was then advanced to the thrombus indicated by the meniscus sign and slowly withdrawn under aspiration. Results: 29 patients underwent MT for AIS using the MCI technique. Even in cases without the meniscus sign on initial angiography, the MCI technique accurately revealed the proximal edge of the thrombus. Moreover, middle cerebral artery occlusion due to atherosclerotic stenosis and displacement of the aspiration catheter and thrombus axis were detected using this technique. Conclusions: The MCI technique may effectively reveal the exact site of a thrombus and increase the success rate of first-pass recanalization.

Outcomes of mechanical thrombectomy in M1 occlusion patients with or without hyperdense middle cerebral artery sign: A systematic review and meta-analysis

BACKGROUND

The comparison of mechanical thrombectomy (MT) outcomes between patients with the hyperdense middle cerebral artery sign (HMCAS) and non-HMCAS is important to evaluate the impact of this radiological finding on treatment efficacy. This meta-analysis aimed to assess the association between HMCAS and clinical outcomes in patients undergoing thrombectomy, comparing the outcomes over non-HMCAS.

METHODS

A systematic literature search was conducted in PubMed, Ovid Embase, Google Scholar, and Cochrane Library to identify studies on MT outcomes for M1 occlusions of HMCAS over non-HMCAS. Inclusion criteria encompassed modified Rankin Scale (mRS) score, mortality, symptomatic intracranial hemorrhage (sICH), and successful recanalization. Using R software version 4.1.2, we calculated pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI).

RESULTS

The meta-analysis was performed for 5 studies with 724 patients. There was no association found between presence of HMCAS and achieving mRS 0-2 (OR = 0.65, 95% CI: 0.29-1.47; p = .544). Mortality analysis also showed no significant association with presence of HMCAS (OR = 0.78, 95% CI: 0.37-1.65; p = .520). No significant difference in sICH risk (OR = 1.54, 95% CI: 0.24-9.66; p = .646) was found between groups. Recanalization analysis showed a non-significant positive association (OR = 1.23, 95% CI: 0.67-2.28; p = .501). Heterogeneity was observed in all analyses.

CONCLUSION

Our findings showed that there is no statistically significant difference in mRS scores, mortality, sICH, and recanalization success rates between the HMCAS and non-HMCAS groups.

Outcome of endovascular thrombectomy in patients with end-stage renal disease undergoing dialysis

BACKGROUND

Patients with end-stage renal disease (ESRD) are often excluded from clinical trials of endovascular thrombectomy (EVT). This study investigated the outcome in these patients.

METHODS

From September 2014 to July 2021, all patients undergoing EVT for anterior circulation stroke in two stroke centers in Taiwan were included. They were divided into no renal dysfunction (non-RD, estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2), RD (eGFR <60 mL/min/1.73 m2 but no dialysis), and ESRD undergoing dialysis (ESRD-dialysis). The clinical features and outcomes were compared.

RESULTS

Of 482 patients included, there were 20 ESRD-dialysis, 110 RD, and 352 non-RD patients. The Alberta Stroke Program Early CT Score (ASPECTS), National Institutes of Health Stroke Scale (NIHSS), use of intravenous thrombolysis, EVT-related time metrics, and successful recanalization rates were comparable among the three groups. However, the ESRD-dialysis patients had more symptomatic intracerebral hemorrhage (ICH, 15% vs 3.6% vs 3.7%), more contrast-induced encephalopathy (15% vs 1.8% vs 0.9%), and a higher mortality at 90 days (35% vs 18% vs 11%) than the other groups. Multivariable analysis revealed that ESRD-dialysis was associated with a less favorable outcome (OR 0.21, 95% CI 0.04 to 0.77) and more severe disability or mortality (modified Rankin Scale 5 or 6; OR 13.1, 95% CI 3.93 to 48.1) at 90 days. In the ESRD-dialysis group, the patients with premorbid functional dependence had a significantly higher mortality than those without (75% vs 8.3%; P=0.004).

CONCLUSION

ESRD-dialysis patients were associated with symptomatic ICH and less favorable outcome at 90 days. Patients with premorbid functional dependency had an excessively high mortality.

Futile reperfusion of endovascular treatment for acute anterior circulation large vessel occlusion in the ANGEL-ACT registry

BACKGROUND

Some patients with large vessel occlusion (LVO) still cannot achieve functional independence despite successful reperfusion after endovascular treatment (EVT), named futile reperfusion. We aimed to explore the incidence and predictors of futile reperfusion of EVT for anterior circulation LVO in the Chinese population based on a nationwide prospective multicenter registry.

METHODS

We selected patients from the ANGEL-ACT (Endovascular Treatment Key Technique and Emergency Workflow Improvement of Acute Ischemic Stroke) registry. Successful reperfusion was defined as modified Treatment In Cerebral Ischemia (mTICI) 2b-3 after EVT, and functional independence was defined as 90-day modified Rankin Scale (mRS) 0-2. A multivariable regression model was performed to identify the independent predictors of futile reperfusion in anterior circulation LVO patients.

RESULTS

A total of 1158 anterior circulation LVO patients were included in our study. 600 of the 1158 patients (51.8%) suffered futile reperfusion. Age ≥69 (adjusted OR (aOR) 1.69, 95% CI 1.21 to 2.35, P=0.002), baseline National Institutes of Health Stroke Scale (NIHSS) ≥14 (aOR 2.36, 95% CI 1.71 to 3.27, P<0.001), baseline serum glucose ≥6.5 mmol/L (aOR 1.73, 95% CI 1.27 to 2.36, P=0.001), drip and ship (aOR 1.56, 95% CI 1.11 to 2.18, P=0.011), and general anesthesia (aOR 2.28, 95% CI 1.66 to 3.14, P<0.001) were associated with a high risk of futile reperfusion in the anterior LVO patients after EVT, whereas baseline Alberta Stroke Program Early CT Score (ASPECTS) ≥8 (aOR 0.65, 95% CI 0.47 to 0.91, P=0.011) and complete reperfusion (aOR 0.62, 95% CI 0.43 to 0.89, P=0.010) were associated with a low risk of futile reperfusion in the anterior LVO patients after EVT.

CONCLUSIONS

In the ANGEL-ACT registry, 51.8% of anterior circulation LVO patients suffered futile reperfusion after EVT. Age ≥69 years, baseline NIHSS ≥14, baseline serum glucose ≥6.5 mmol/L, drip and ship, general anesthesia, baseline ASPECTS <8, and incomplete reperfusion were the independent predictors of futile reperfusion.

Thrombectomy in M2 occlusion compared to M1 occlusion: treatment effects of Thrombolysis In Cerebral Infarction (TICI) 2b and TICI 3 recanalization on functional outcome

BACKGROUND

Emerging data suggest that mechanical thrombectomy (MT) might also be safe and efficient for medium and distal occlusions. This study aims to compare average treatment effects on functional outcome of different degrees of recanalization after MT in patients with M2 occlusion and M1 occlusion.

METHODS

All patients enrolled in the German Stroke Registry (GSR) between June 2015 and December 2021 were analyzed. Inclusion criteria were stroke with primary M1 occlusion or M2 occlusion, and availability of relevant clinical data. 4259 patients were included, thereof 1353 with M2 occlusion and 2906 with M1 occlusion. Treatment effects were analyzed using double-robust inverse-probability-weighted regression-adjustment (IPWRA) estimators to control for confounding covariates. Binarized endpoint metrics were defined as good outcome with modified Rankin Scale (mRS) ≤2 at 90 days, and linearized endpoint metrics were defined as mRS shift pre-stroke to 90 days. Effects were evaluated for near complete recanalization (Thrombolysis In Cerebral Infarction scale (TICI) 2b) and complete recanalization (TICI 3).

RESULTS

Treatment effect estimation for TICI ≥2b versus TICI <2b in M2 occlusions showed an increase in the probability of a good outcome from 27% to 47% with a number-needed-to-treat (NNT) of 5. For M1 occlusions the probability of a good outcome increased from 16% to 38% with NNT 4.5. TICI 3 versus TICI 2b increased the probability of a good outcome by 7 percentage points in M1 occlusions; for M2 occlusions the beneficial effect was not significant.

CONCLUSIONS

Results suggest that successful recanalization with TICI ≥2b versus TICI <2b after MT in M2 occlusions provides significant patient benefit with treatment effects comparable to M1 occlusions. The probability of functional independence increased by 20 percentage points (NNT 5) and stroke-related mRS increase was reduced by 0.9 mRS points. In contrast to M1 occlusions, complete recanalization TICI 3 versus TICI 2b had lower additional beneficial effect.

Postoperative blood glucose increase is associated with futile recanalization in patients with successful thrombectomy: a retrospective study

BACKGROUND

Timely recognition of futile recanalization might enable a prompt response and an improved outcome in post-thrombectomy patients. This study aims to evaluate whether postoperative blood glucose increase (BGI) could act as an indicator of futile recanalization in patients receiving a successful thrombectomy.

METHODS

This is a single-center, retrospective analysis of patients with anterior circulation large-vessel occlusion and successful thrombectomy between February 2019 and June 2022. BGI was defined as a higher level of blood glucose at the first postoperative morning than at admission. Futile recanalization was defined as patients with a modified Rankin Scale score of 3-6 at 90 days after onset. Multivariable binary logistic regression was used to assess the association of BGI with futile recanalization.

RESULTS

A total of 276 patients were enrolled, amongst which 120 patients (43.5%) had BGI. Futile recanalization was more prevalent among patients with BGI compared to those without (70.0 vs. 49.4%, P = 0.001). After adjusting for potential confounders, BGI was associated with a higher likelihood of futile recanalization (adjusted OR: 2.97, 95%CI: 1.50-5.86, P = 0.002). This association was consistently observed regardless of diabetes history, occlusion site, time from symptom onset to groin puncture, or reperfusion status.

CONCLUSION

Our findings support BGI serving as an indicator of futile recanalization in patients with anterior circulation large-vessel occlusion and successful thrombectomy.

Shorter Reperfusion Time in Stroke is Associated with Better Cognition

BACKGROUND

Cognitive changes that result from cerebrovascular disease contribute to a poor functional outcome with reduced quality of life. Among patients undergoing endovascular therapy (EVT), we aim to assess cognitive function and evaluate the impact of reperfusion time in cognitive performance.

METHODS

Patients with acute right anterior circulation strokes that underwent EVT between January 2018 and August 2020 at Centro Hospitalar de Vila Nova de Gaia/Espinho, participated in the study. Modified treatment in cerebral infarction (mTICI) assessed the level of recanalization. Cognitive evaluation was assessed with Addenbrooke's Cognitive Examination revised (ACE-R). Multiple linear regression analyses were used to determine the association between time for recanalization and ACE-R. The level of significance adopted was 0.05.

RESULTS

The mean age of participants was 71.5 (interquartile range [IQR] 62.0-78.2) years, and 50% (22) were women. The median time after stroke was 28.6 months (IQR 18.94-31.55). All patients in our sample had a successful level of recanalization with EVT (mTICI ≥ 2b). Time for recanalization showed an inverse association with the ACE-R (b = -0.0207, P = 0.0203). Also the mRS at 3 months had an inverse association with cognition (b = -5.2803, p = 0.0095). Level of education had a strong and direct relationship with ACE-R results (b = 3.0869, p < 0.0001).

CONCLUSIONS

Longer time between stroke symptoms and recanalization with EVT in patients with right hemisphere ischemic stroke lead to lower ACE-R scores. Measures to improve door-to-recanalization time are also important for cognitive performance after ischemic stroke.

Adhesion of vessel wall to stentriever during combined technique for mechanical thrombectomy in acute ischemic stroke: A histomorphological study

PURPOSE

Detection of vessel wall tissue in thrombus material in patients with ischemic stroke is judged as vascular injury. So far, several studies investigated components of the free clots after mechanical thrombectomy. The aim of this retrospective study was to investigate the involvement and role of the stentriever in vessel wall injury by analysis of the composition of adherent tissue to the stentriever during combined aspiration thrombectomy with stentriever.

METHODS

Stentriever with adherent tissue and free clots in aspiration samples from patients undergoing mechanical thrombectomy (aspiration plus stentriever) were separately assessed for the occurrence of parts of vascular tissue together with clinical and interventional data as well as clinical outcome data. Specimens were analyzed histomorphologically and immunohistochemically. Findings, focused on parts of vessel wall were reported together with clinical data.

RESULTS

Specimens from 21 identified patients were available. Parts of the vessel wall were detected in 7 out 21 (33%) samples. All specimens revealed fresh thrombus material without signs of organization or atheromatous tissue. In 90% of patients mTICI was greater than 2b without signs of secondary vessel injury. No vascular tissue was found in free clots of the aspiration samples.

CONCLUSION

The examination of adherent tissue to the stentriever instead of the examination of free clots may affect the number of detected parts of vessel wall. Further studies in combination with vessel wall imaging may elucidate the origin of remnants of vessel wall.

First pass effect of mechanical thrombectomy for acute vertebrobasilar artery occlusion: data from the ANGEL-ACT registry

BACKGROUND

To explore the incidence, predictors, and association of first pass effect (FPE) on clinical outcomes of mechanical thrombectomy (MT) for acute vertebrobasilar artery occlusion (VBAO) in the Asian population.

METHODS

We selected patients from the ANGEL-ACT registry. We defined FPE as complete recanalization after one MT attempt without rescue treatment, multiple pass effect (MPE) as complete recanalization after >1 MT attempt or after one MT attempt with rescue treatment, and incomplete recanalization (ICR) as a modified Thrombolysis in Cerebral Ischemia score of 2b, independent of the number of MT attempts. We conducted multivariable logistic analyses to identify the independent predictors of FPE and to compare the outcomes, including favorable outcome, mortality within 90 days, and intracranial hemorrhage (ICH) among the FPE, MPE, and ICR groups.

RESULTS

Two hundred and seventy-nine patients, 68 with FPE (24.4%), 114 with MPE (40.9%), and 83 with ICR (29.7%), were included. Underlying intracranial atherosclerosis disease (ICAD) (adjusted OR (aOR) 0.16, 95% CI 0.08 to 0.34, P<0.001) was independently associated with a low chance of FPE. Furthermore, FPE was associated with a favorable outcome compared with MPE and ICR (MPE vs FPE, aOR 0.49, 95% CI 0.25 to 0.97, P=0.040; ICR vs FPE, aOR 0.38, 95% CI 0.18 to 0.81, P=0.012), and decreased mortality (MPE vs FPE, aOR 2.57, 95% CI 1.04 to 6.36, P=0.041) compared with MPE but similar mortality to ICR (P=0.374). No difference was found for ICH among the three groups (P>0.05).

CONCLUSIONS

FPE occurred in 24.4% of patients with VBAO in our cohort, which was associated with improved clinical outcomes compared with MPE and ICR. VBAO with underlying ICAD was less likely to achieve FPE.

TRIAL REGISTRATION NUMBER

NCT03370939.

Endovascular thrombectomy for basilar-artery occlusion: A meta-analysis with trial sequential analysis

Background and purpose

Basilar-artery occlusion (BAO) usually accounts for devastating neurologic sequelae, poor prognosis, and even death. While endovascular thrombectomy (EVT) is the most successful treatment for anterior circulation stroke with large vessel occlusion, its effectiveness in treating acute BAO is still debatable. Our aim is to compare the efficacy and safety between EVT and conservative medical treatment (CMT) in BAO.

Methods

Up until May 2022, relevant literature was gathered using searches in Embase, PubMed, and the Cochrane Library. The primary outcomes were defined as good functional outcome (modified Rankin Scale 0-2) and favorable functional outcome (modified Rankin Scale 0-3) at 3 months between EVT and CMT groups. The secondary outcomes included mortality at 3 months, symptomatic intracerebral hemorrhage (ICH), and any ICH.

Results

Eight studies involving 3733 patients with BAO were enrolled 2573 individuals underwent EVT, and the remaining 1160 patients received CMT. Compared with CMT, EVT achieved more favorable functional outcome (odds ratio (OR) 1.26, 95% CI 1.03-1.55, I2 = 54%, p = 0.05) in BAO. The good functional outcome showed a similar tendency (OR 1.23, 95% CI 0.97-1.57, I2 = 63%, p = 0.02) as well. EVT decreased mortality at 3 months (OR 0.81, 95% CI 0.70-0.93, I2 = 31 %, p = 0.19), although having a tendency to cause symptomatic ICH (OR 2.91, 95% CI 1.38-6.18, I2 = 22 %, p = 0.27).

Conclusions

EVT in BAO provides superior functional outcomes and less mortality compared with CMT. Even though EVT has the propensity to cause symptomatic ICH, EVT nevertheless improved posterior circulation stroke.

Postoperative fibrinogen-to-albumin ratio acting as an indicator of futile recanalization in patients with successful thrombectomy

BACKGROUND

Timely recognition of futile recanalization might enable a prompter response and thus improve outcomes in patients receiving successful thrombectomy. This study aims to evaluate whether postoperative fibrinogen-to-albumin ratio (FAR) could act as an indicator of futile recanalization.

METHODS

This is a single-center, retrospective analysis of patients with acute anterior circulation large-vessel occlusion and successful thrombectomy between May 2019 and June 2022. FAR was defined as postoperative blood levels of fibrinogen divided by those of albumin, and dichotomized into high and low levels based on the Youden index. Futile recanalization was defined as patients achieving a successful recanalization with a modified Rankin Scale score of 3-6 at 90 days. Multivariable logistic regression was used to assess the association of FAR with futile recanalization.

RESULTS

A total of 255 patients were enrolled, amongst which 87 patients (34.1%) had high postoperative FAR. Futile recanalization was more prevalent among patients with high FAR compared to those with low FAR (74.7% vs. 53.0%, p = .001). After adjusting for potential confounders, high postoperative FAR was found to independently correspond with the occurrence of futile recanalization (adjusted OR 2.40, 95%CI 1.18-4.87, p = .015). This association was consistently observed regardless of prior antithrombotic therapy, treatment of intravenous thrombolysis, occlusion site, time from symptom onset to groin puncture, and reperfusion status.

CONCLUSION

Our findings support high postoperative FAR serving as an indicator of futile recanalization in patients with anterior circulation large-vessel occlusion and successful thrombectomy.

Outcome prediction value of critical area perfusion score for acute basilar artery occlusion

PURPOSE

To investigate the performance of the Critical Area Perfusion Score (CAPS), based on computed tomography perfusion (CTP) time to maximum (Tmax) > 10s maps, to predict the outcome in acute basilar artery occlusion (BAO) in patients undergoing endovascular treatment (EVT).

METHODS

We perform a retrospective analysis of a prospectively collected database of acute BAO treated with EVT in a comprehensive stroke center. The favorable outcome was defined as the 90-day modified Rankin Scale (mRS) ≤ 3. We performed the logistic regression analysis to find the independent predictors of the favorable outcome. Then, we used receiver operating characteristic analyses to assess the predictive value of the imaging parameters, including CAPS, Posterior Circulation Alberta Stroke Program Early CT Score (PC-ASPECTS), pons midbrain index (PMI), posterior circulation computed tomography angiography (PC-CTA) score, Basilar Artery on Computed Tomography Angiography (BATMAN) score, and CTP parameters. Finally, the Delong test was used to compare the area under the curve (AUC) of CAPS against the other imaging parameters.

RESULTS

Of the 65 enrolled patients, the incidence of the favorable outcome was 44.6% (29/65). Low CAPS (per 1- point increased odds ratio [OR], 0.43; 95% confidence interval [CI], 0.22-0.86; P = 0.017) and admission National Institutes of Health Stroke Scale (NIHSS) (per 1- point increased OR, 0.80; 95% CI, 0.70-0.91; P = 0.001) were independently associated with favorable outcome. The AUC of CAPS was 0.83 (95% CI, 0.74-0.93; P < 0.001) with ≤ 3 cut-off value, 89.66% sensitivity, 77.22% specificity, and 80.00% accuracy, which was greater than the other imaging parameters (All P for Delong test < 0.05).

CONCLUSIONS

CAPS was the most accurate imaging-based outcome predictor in acute BAO patients. Future large prospective multicenter studies are needed to verify these results.

Impact of atrial fibrillation on the treatment effect of bridging thrombolysis in ischemic stroke patients undergoing endovascular thrombectomy: a multicenter international cohort study

BACKGROUND

The role of bridging intravenous thrombolysis (IVT) before endovascular thrombectomy (EVT) in the treatment of acute ischemic stroke (AIS) remains debatable. Atrial fibrillation (AF) associated strokes may be associated with reduced treatment effect from IVT. This study compares the effect of bridging IVT in AF and non-AF patients.

METHODS

This retrospective cohort study comprised anterior circulation large vessel occlusion (LVO) AIS patients receiving EVT alone or bridging IVT plus EVT within 6 hours of symptom onset. Primary outcome was good functional outcome defined as modified Rankin Scale (mRS) 0-2 at 90 days. Secondary outcomes were successful reperfusion defined as expanded Thrombolysis In Cerebral Infarction (eTICI) grading ≥2b flow, symptomatic intracerebral hemorrhage (sICH), and in-hospital mortality.

RESULTS

We included 705 patients (314 AF and 391 non-AF patients). The mean age was 68.6 years and 53.9% were male. The odds of good functional outcomes with bridging IVT was higher in the non-AF (adjusted odds ratio (aOR) 2.28, 95% CI 1.06 to 4.91, P=0.035) compared with the AF subgroups (aOR 1.89, 95% CI 0.89 to 4.01, P=0.097). However, this did not constitute a significant effect modification by the presence of AF on bridging IVT (interaction aOR 0.12, 95% CI -1.94 to 2.18, P=0.455). The rate of successful reperfusion, sICH, and mortality were similar between bridging IVT and EVT for both AF and non-AF patients.

CONCLUSION

The presence of AF did not modify the treatment effect of bridging IVT. Further individual patient data meta-analysis of randomized trials may shed light on the comparative efficacy of bridging IVT in AF versus non-AF LVO strokes.

Reperfusion by endovascular thrombectomy and early cerebral edema in anterior circulation stroke: Results from the SITS-International Stroke Thrombectomy Registry

BACKGROUND

A large infarct and expanding cerebral edema (CED) due to a middle cerebral artery occlusion confers a 70% mortality unless treated surgically. There is still conflicting evidence whether reperfusion is associated with a lower risk for CED in acute ischemic stroke.

AIM

To investigate the association of reperfusion with development of early CED after stroke thrombectomy.

METHODS

From the SITS-International Stroke Thrombectomy Registry, we selected patients with occlusion of the intracranial internal carotid or middle cerebral artery (M1 or M2). Successful reperfusion was defined as mTICI ⩾ 2b. Primary outcome was moderate or severe CED, defined as focal brain swelling ⩾1/3 of the hemisphere on imaging scans at 24 h. We used regression methods while adjusting for baseline variables. Effect modification by severe early neurological deficits, as indicators of large infarct at baseline and at 24 h, were explored.

RESULTS

In total, 4640 patients, median age 70 years and median National Institutes of Health Stroke Score (NIHSS) 16, were included. Of these, 86% had successful reperfusion. Moderate or severe CED was less frequent among patients who had reperfusion compared to patients without reperfusion: 12.5% versus 29.6%, p < 0.05, crude risk ratio (RR) 0.42 (95% confidence interval (CI): 0.37-0.49), and adjusted RR 0.50 (95% CI: 0.44-0.57). Analysis of effect modification indicated that severe neurological deficits weakened the association between reperfusion and lower risk of CED. The RR reduction was less favorable in patients with severe neurological deficits, defined as NIHSS score 15 or more at baseline and at 24 h, used as an indicator for larger infarction.

CONCLUSION

In patients with large artery anterior circulation occlusion stroke who underwent thrombectomy, successful reperfusion was associated with approximately 50% lower risk for early CED. Severe neurological deficit at baseline seems to be a predictor for moderate or severe CED also in patients with successful reperfusion by thrombectomy.

Distal placement of balloon guide catheter facilitates stent-retriever mechanical thrombectomy for acute ischemic stroke in the anterior circulation

PURPOSE

Although balloon guide catheters (BGCs) have been demonstrated to improve recanalization and functional outcomes by enabling proximal flow control and forced aspiration during mechanical thrombectomy (MT), the significance of the BGC location has been overlooked. We evaluated the impact of BGC location during MT for anterior circulation acute ischemic stroke (AIS).

METHODS

Patients were divided into the proximal and distal BGC groups according to the BGC tip location relative to the lower margin of the C1 vertebral body. Endovascular and clinical outcomes were compared between the two groups, including subgroup analyses of the two types of extracranial internal carotid artery (ICA) anatomy, categorized based on cerebral angiography.

RESULTS

A total of 124 patients were analyzed, with 62 each in the proximal and distal BGC placement groups. The distal BGC group had higher rates of first-pass recanalization (FPR) (38.7% vs. 17.7%, P = 0.009) and favorable outcomes (64.5% vs. 46.8%, P = 0.047) with shorter procedure time (47.5 min vs. 65 min, P = 0.001) and fewer distal embolization (3.2% vs. 12.9%, P = 0.048) than the proximal BGC group. FPR was also more frequently achieved in the distal BGC group of patients with tortuous ICA (37.0% vs. 12.5%, P = 0.029). Multivariate analysis showed that distal BGC placement was an independent predictor of FPR (odds ratio, 3.092; 95% confidence interval, 1.326-7.210; P = 0.009).

CONCLUSION

Distal BGC placement facilitates MT for AIS in the anterior circulation. Therefore, we suggest distal BGC placement to maximize the effect of thrombectomy, even for tortuous extracranial ICA.

Priorities for Advancements in Neuroimaging in the Diagnostic Workup of Acute Stroke

STAIR XII (12th Stroke Treatment Academy Industry Roundtable) included a workshop to discuss the priorities for advancements in neuroimaging in the diagnostic workup of acute ischemic stroke. The workshop brought together representatives from academia, industry, and government. The participants identified 10 critical areas of priority for the advancement of acute stroke imaging. These include enhancing imaging capabilities at primary and comprehensive stroke centers, refining the analysis and characterization of clots, establishing imaging criteria that can predict the response to reperfusion, optimizing the Thrombolysis in Cerebral Infarction scale, predicting first-pass reperfusion outcomes, improving imaging techniques post-reperfusion therapy, detecting early ischemia on noncontrast computed tomography, enhancing cone beam computed tomography, advancing mobile stroke units, and leveraging high-resolution vessel wall imaging to gain deeper insights into pathology. Imaging in acute ischemic stroke treatment has advanced significantly, but important challenges remain that need to be addressed. A combined effort from academic investigators, industry, and regulators is needed to improve imaging technologies and, ultimately, patient outcomes.

Regulatory T cells: A suppressor arm in post-stroke immune homeostasis

The activation of the immune system and the onset of pro- and anti-inflammatory responses play crucial roles in the pathophysiological processes of ischaemic stroke (IS). CD4+ regulatory T (Treg) cells is the main immunosuppressive cell population that is studied in the context of peripheral tolerance, autoimmunity, and the development of chronic inflammatory diseases. In recent years, more studies have focused on immune modulation after IS, and Treg cells have been demonstrated to be essential in the remission of inflammation, nerve regeneration, and behavioural recovery. However, the exact effects of Treg cells in the context of IS remain controversial, with some studies suggesting a negative correlation with stroke outcomes. In this review, we aim to provide a comprehensive overview of the current understanding of Treg cell involvement in post-stroke homeostasis. We summarized the literature focusing on the temporal changes in Treg cell populations after IS, the mechanisms of Treg cell-mediated immunomodulation in the brain, and the potential of Treg cell-based therapies for treatment. The purposes of the current article are to address the importance of Treg cells and inspire more studies to help physicians, as well as scientists, understand the whole map of immune responses during IS.

Safety Outcomes of Antiplatelet Therapy During Endovascular Treatment of Tandem Lesions in Acute Ischemic Stroke Patients

Risk of hemorrhage remains with antiplatelet medications required with carotid stenting during endovascular therapy (EVT) for tandem lesion (TLs). We evaluated the safety of antiplatelet regimens in EVT of TLs. This multicenter study included anterior circulation TL patients from 2015 to 2020, stratified by periprocedural EVT antiplatelet strategy: (1) no antiplatelets, (2) single oral, (3) dual oral, and (4) intravenous IV (in combination with single or dual oral). Primary outcome was symptomatic intracranial hemorrhage (sICH). Secondary outcomes were any hemorrhage, favorable functional status (mRS 0-2) at 90 days, successful reperfusion (mTICI score ≥ 2b), in-stent thrombosis, and mortality at 90 days. Of the total 691 patients, 595 were included in the final analysis. One hundred and nineteen (20%) received no antiplatelets, 134 (22.5%) received single oral, 152 (25.5%) dual oral, and 196 (31.9%) IV combination. No significant association was found for sICH (ref: no antiplatelet: 5.7%; single:4.2%; aOR 0.64, CI 0.20-2.06, p = 0.45, dual:1.9%; aOR 0.35, CI 0.09-1.43, p = 0.15, IV combination: 6.1%; aOR 1.05, CI 0.39-2.85, p = 0.92). No association was found for parenchymal or petechial hemorrhage. Odds of successful reperfusion were significantly higher with dual oral (aOR 5.85, CI 2.12-16.14, p = 0.001) and IV combination (aOR 2.35, CI 1.07-5.18, p = 0.035) compared with no antiplatelets. Odds of excellent reperfusion (mTICI 2c/3) were significantly higher for cangrelor (aOR 4.41; CI 1.2-16.28; p = 0.026). No differences were noted for mRS 0-2 at 90 days, in-stent thrombosis, and mortality rates. Administration of dual oral and IV (in combination with single or dual oral) antiplatelets during EVT was associated with significantly increased odds of successful reperfusion without an increased rate of symptomatic hemorrhage or mortality in patients with anterior circulation TLs.

First-in-human trial of a self-expandable, temporary dilation system for intracranial atherosclerotic disease in patients presenting with acute ischemic stroke

BACKGROUND

Intracranial atherosclerotic disease (ICAD) significantly contributes to ischemic stroke, especially among Asian populations. Large vessel occlusion (LVO) due to underlying ICAD accounts for 15-35% of acute ischemic stroke cases requiring endovascular therapy. However, the successful recanalization rate of ICAD-related LVO remains lower. The TG dilator is a self-expandable device, temporarily dilating ICAD-related blocked blood vessels.

OBJECTIVE

To demonstrate TG dilator safety and efficacy for ICAD-related acute ischemic stroke.

METHODS

This was a single-arm, open-label, non-randomized, prospective, multicenter, and investigator-initiated trial that involved patients undergoing TG dilator application for acute ischemic stroke caused by ICAD-related LVO or severe stenosis.

RESULTS

We enrolled 10 patients in this trial between November 2022 and April 2023. The median (IQR) age was 68 (59.3-75.3) years. Before using the dilator, seven patients received stent retriever treatment. All 10 patients were prescribed a loading dose of aspirin with prasugrel. The median application time was 10 (10-12) min. At the end of the procedure, we achieved significant recanalization immediately in all patients. The stenosis/occlusion decreased from 100% (100-100) to 68% (56.3-75.3). No patient experienced recurrent ischemic stroke or reocclusion within 90 days. We achieved a modified Rankin scale score of 0-2 in 8 patients by day 90. We detected no cases of intracranial hemorrhage, equipment failure, distal embolism, vasospasm, dissection, or perforation requiring intervention.

CONCLUSIONS

Acute revascularization using the TG dilator on patients with ICAD-related LVO or severe stenosis did not cause any significant adverse event, and consistently improved blood flow at 90 days.

Japan Trevo Registry: Real-world Registry of Stent Retriever Alone or in Combined Therapy with Aspiration Catheter for Acute Ischemic Stroke in Japan

Endovascular therapy (EVT) for real-world patients after extended time frames is associated with concerns about its efficacy and safety. We conducted a prospective registry at 77 centers between November 2019 and October 2020. The registry criteria included patients treated with Trevo Retriever alone or in combined therapy with an aspiration catheter. The primary outcome was effective reperfusion (thrombolysis in cerebral infarction grade ≥ 2b), the secondary outcome was a modified Rankin scale 0-2 at 90 days, and the safety outcomes were worsening of neurologic symptoms within 24 h postoperatively, intracranial hemorrhage (ICH) within 24 h after EVT and mortality. We also exlpored the difference between patients whose last known well time (LKWT) to a puncture was less than 6 h (0-6 h) and those whose LKWT was 6 h or more but less than 24 h (6-24 h). Among the 1041 patients registered, 1025 patients were analyzed. The mean age was 76.9 years, and 53.6% of the participants were males. The 6-24 h group was 206/998 (20.6%), the median National Institute of Health Stroke Scale (NIHSS) score at admission was 18, and the median Alberta Stroke Program Early CT score was 8. Combined technique as the first pass was used on 817 (79.7%) patients. The primary outcome was 934 (91.1%). The secondary outcome was 433/1021 (42.4%). Symptomatic ICH, any ICH, and mortality were 10/1019 (1.0%), 311/1019 (30.5%), and 75 (7.3%). In the subanalysis, the 6-24 h group was lower in NIHSS (median;18 vs 16), and the secondary outcome was not significantly different in the <6 h group. Even after treatment time expansion, this result was comparable to other Trevo-based trials and nationwide registries.

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 2023; DOI: 10.1055/a-2175-4029.

Prognostic Value of Histopathological Thrombus Age in Large Vessel Occlusion-Related Stroke

INTRODUCTION

Acute mechanical thrombectomy (MT) is the preferred treatment for large vessel occlusion-related stroke. Histopathological research on the obtained occlusive embolic thrombus may provide information regarding the aetiology and pathology of the lesion to predict prognosis and propose possible future acute ischaemic stroke therapy.

METHODS

A total of 75 consecutive patients who presented to the Amphia Hospital with acute large vessel occlusion-related stroke and underwent MT were included in the study. The obtained thrombus materials were subjected to standard histopathological examination. Based on histological criteria, they were considered fresh (<1 day old) or old (>1 day old). Patients were followed for 2 years for documentation of all-cause mortality.

RESULTS

Thrombi were classified as fresh in 40 patients (53%) and as older in 35 patients (47%). Univariate Cox regression analysis showed that thrombus age, National Institutes of Health Stroke Scale at hospital admission, and patient age were associated with long-term mortality (p < 0.1). Multivariable Cox hazards and Kaplan-Meier analysis demonstrated that after extensive adjustment for clinical and procedural variables, thrombus age persisted in being independently associated with higher long-term mortality (hazard ratio: 3.34; p = 0.038, log-rank p = 0.013).

CONCLUSION

In this study, older thromboemboli are responsible for almost half of acute large ischaemic strokes. Moreover, the presence of an old thrombus is an independent predictor of mortality in acute large vessel occlusion-related stroke. More research is warranted regarding future therapies based on thrombus composition.

Effect of the anastomosis between the posterior inferior cerebellar artery and the superior cerebellar artery on outcomes of acute basilar artery occlusion after endovascular treatment

BACKGROUND

The effects of secondary collateral compensation on outcomes remain unclear in patients with acute basilar artery occlusion (BAO) after endovascular treatment (EVT). This study aimed to evaluate the benefits of the anastomosis between the posterior inferior cerebellar artery (PICA) and the superior cerebellar artery (SCA) in BAO after EVT.

METHODS

This cohort study was conducted using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry. Patients with acute BAO and treated with EVT were included. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (SICH) and 90-day mortality.

RESULTS

Of the 646 patients included in the study, 196 (30.3%) patients had a PICA-SCA anastomosis. The PICA-SCA anastomosis was significantly associated with independent functional outcome at 90 days (67/196 (34.2%) vs 109/450 (24.2%), adjusted OR (aOR) 1.80 (95% CI 1.13 to 2.86), p=0.01) and was significantly associated with a decreased rate of SICH (40/442 (9.0%) vs 5/193 (2.6%), aOR 0.29 (95% CI 0.11 to 0.76), p=0.01). No significant difference was found between PICA-SCA anastomosis and 90-day mortality (219/450 (48.7%) vs 80/196 (40.8%), aOR 0.72 (95% CI 0.48 to 1.08), p=0.11). Subgroup analysis showed that the association between independent functional outcome and PICA-SCA anastomosis was strongest in patients with middle BAO (27/77 (35.1%) vs 22/118 (18.6%), aOR 2.64 (95% CI 1.13 to 6.15), p=0.03).

CONCLUSIONS

The PICA-SCA anastomosis is significantly associated with better functional outcomes in patients with acute BAO after EVT, especially in those with middle BAO.

Risk factors and predictors of intracranial hemorrhage after mechanical thrombectomy in acute ischemic stroke: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

Reducing intracranial hemorrhage (ICH) can improve patient outcome in acute ischemic stroke (AIS) intervention. We sought to identify ICH risk factors after AIS thrombectomy.

METHODS

This is a retrospective review of the Stroke Thrombectomy and Aneurysm Registry (STAR) database. All patients who underwent AIS thrombectomy with available ICH data were included. Multivariable regression models were developed to identify predictors of ICH after thrombectomy. Subgroup analyses were performed stratified by symptom status and European Cooperative Acute Stroke Study (ECASS) grade.

RESULTS

The study cohort comprised 6860 patients. Any ICH and symptomatic ICH (sICH) occurred in 25% and 7% of patients, respectively. Hemorrhagic infarction 1 (HI1) occurred in 36%, HI2 in 24%, parenchymal hemorrhage 1 (PH1) in 22%, and PH2 in 17% of patients classified by ECASS grade. Intraprocedural complications independently predicted any ICH (OR 3.8083, P<0.0001), PH1 (OR 1.9053, P=0.0195), and PH2 (OR 2.7347, P=0.0004). Race also independently predicted any ICH (black: OR 0.5180, P=0.0017; Hispanic: OR 0.4615, P=0.0148), sICH (non-white: OR 0.4349, P=0.0107), PH1 (non-white: OR 3.1668, P<0.0001), and PH2 (non-white: OR 1.8689, P=0.0176), with white as the reference. Primary mechanical thrombectomy technique also independently predicted ICH. ADAPT (A Direct Aspiration First Pass Technique) was a negative predictor of sICH (OR 0.2501, P<0.0001), with stent retriever as the reference.

CONCLUSIONS

This study identified ICH risk factors after AIS thrombectomy using real-world data. There was a propensity towards a reduced sICH risk with direct aspiration. Procedural complications and ethnicity were predictors congruent between categories of any ICH, sICH, PH1, and PH2. Further investigation of technique and ethnicity effects on ICH and outcomes after AIS thrombectomy is warranted.

Association of intravenous thrombolysis and pre-interventional reperfusion: a post hoc analysis of the SWIFT DIRECT trial

BACKGROUND

A potential benefit of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) is pre-interventional reperfusion. Currently, there are few data on the occurrence of pre-interventional reperfusion in patients randomized to IVT or no IVT before MT.

METHODS

SWIFT DIRECT (Solitaire With the Intention For Thrombectomy Plus Intravenous t-PA vs DIRECT Solitaire Stent-retriever Thrombectomy in Acute Anterior Circulation Stroke) was a randomized controlled trial including acute ischemic stroke IVT eligible patients being directly admitted to a comprehensive stroke center, with allocation to IVT with MT versus MT alone. The primary endpoint of this analysis was the occurrence of pre-interventional reperfusion, defined as a pre-interventional expanded Thrombolysis in Cerebral Infarction score of ≥2a. The effect of IVT and potential treatment effect heterogeneity were analyzed using logistic regression analyses.

RESULTS

Of 396 patients, pre-interventional reperfusion occurred in 20 (10.0%) patients randomized to IVT with MT, and in 7 (3.6%) patients randomized to MT alone. Receiving IVT favored the occurrence of pre-interventional reperfusion (adjusted OR 2.91, 95% CI 1.23 to 6.87). There was no IVT treatment effect heterogeneity on the occurrence of pre-interventional reperfusion with different strata of Randomization-to-Groin-Puncture time (p for interaction=0.33), although the effect tended to be stronger in patients with a Randomization-to-Groin-Puncture time >28 min (adjusted OR 4.65, 95% CI 1.16 to 18.68). There were no significant differences in rates of functional outcomes between patients with and without pre-interventional reperfusion.

CONCLUSION

Even for patients with proximal large vessel occlusions and direct access to MT, IVT resulted in an absolute increase of 6% in rates of pre-interventional reperfusion. The influence of time strata on the occurrence of pre-interventional reperfusion should be studied further in an individual patient data meta-analysis of comparable trials.

TRIAL REGISTRATION NUMBER

clinicaltrials.gov NCT03192332.

The Charlotte Large artery occlusion Endovascular therapy Outcome Score predicts independent outcome after thrombectomy

BACKGROUND AND PURPOSE

Predicting functional outcomes after endovascular thrombectomy (EVT) is of interest to patients and families as they navigate hospital and post-acute care decision-making. We evaluated the prognostic ability of several scales to predict good neurological function after EVT.

METHODS

We retrospectively analyzed records from a health system's code stroke registry, including consecutive successful thrombectomy patients from August 2020 to February 2023 presenting with an anterior circulation large vessel occlusion who were evaluated with pre-EVT CT perfusion. Primary and secondary outcomes were 90-day modified Rankin Scale (mRS) scores 0-2 and 0-1, respectively. Logistic regression was performed to evaluate the ability of each scale to predict the outcomes. Scales were compared by calculating the area under the curve (AUC).

RESULTS

A total of 465 patients (mean age 68.1 [±14.9] years, median National Institutes of Health Stroke Scale [NIHSS] 16 [11-21]) met inclusion criteria. In the logistic regression, the Charlotte Large artery occlusion Endovascular therapy Outcome Score (CLEOS), Totaled Health Risks in Vascular Events, Houston Intra-Arterial Therapy-2, Pittsburgh Response to Endovascular therapy, and Stroke Prognostication using Age and NIHSS were significant in predicting the primary and secondary outcomes. CLEOS was superior to all other scales in predicting 90-day mRS 0-2 (AUC .75, 95% confidence interval [CI] .70-.80) and mRS 0-1 (AUC .74, 95% CI .69-.78). Twenty of 22 patients (90.9%) with CLEOS <315 had 90-day mRS 0-2.

CONCLUSIONS

CLEOS predicts independent and excellent neurological function after anterior circulation EVT.

Sexual dimorphism in peripheral blood cell characteristics linked to recanalization success of endovascular thrombectomy in acute ischemic stroke

Endovascular thrombectomy (EVT) success to treat acute ischemic stroke varies with factors like stroke etiology and clot composition, which can differ between sexes. We studied if sex-specific blood cell characteristics (BCCs) are related to recanalization success. We analyzed electronic health records of 333 EVT patients from a single intervention center, and extracted 71 BCCs from the Sapphire flow cytometry analyzer. Through Sparse Partial Least Squares Discriminant Analysis, incorporating cross-validation and stability selection, we identified BCCs associated with successful recanalization (TICI 3) in both sexes. Stroke etiology was considered, while controlling for cardiovascular risk factors. Of the patients, successful recanalization was achieved in 51% of women and 49% of men. 21 of the 71 BCCs showed significant differences between sexes  (pFDR-corrected < 0.05). The female-focused recanalization model had lower error rates than both combined [t(192.4) = 5.9, p < 0.001] and male-only models [t(182.6) = - 15.6, p < 0.001]. In women, successful recanalization and cardioembolism were associated with a higher number of reticulocytes, while unsuccessful recanalization and large artery atherosclerosis (LAA) as cause of stroke were associated with a higher mean corpuscular hemoglobin concentration. In men, unsuccessful recanalization and LAA as cause of stroke were associated with a higher coefficient of variance of lymphocyte complexity of the intracellular structure. Sex-specific BCCs related to recanalization success varied and were linked to stroke etiology. This enhanced understanding may facilitate personalized treatment for acute ischemic stroke.

Intravenous tirofiban following successful reperfusion in intracranial large artery atherosclerotic stroke: A secondary analysis of a randomized clinical trial

OBJECTIVE

This study aimed to investigate whether treatment with adjunct intravenous tirofiban is associated with improved outcomes following successful reperfusion in patients with intracranial atherosclerotic stroke.

METHODS

Patients with intracranial large artery atherosclerotic (LAA) stroke and an expanded Treatment in Cerebral Ischemia angiographic score of 2b50 to 3 from the Effect of Intravenous Tirofiban versus Placebo Before Endovascular Thrombectomy on Functional Outcomes in Large Vessel Occlusion Stroke (RESCUE BT) trial were included. The primary outcome was the difference in proportion of independent functional outcome (modified Rankin score of 0-2 at 90 days). Safety outcomes included the rates of symptomatic intracranial hemorrhage (sICH) and 90-day mortality.

RESULTS

Among the 382 patients with intracranial LAA stroke and successful reperfusion, 175 patients (45.8%) were treated with intravenous tirofiban and 207 (54.2%) with placebo. The proportion of patients with independent functional outcome at 90 days was 54.3% (95 out of 175) with tirofiban and 44.0% (91 out of 207) with placebo (adjusted odds ratio [aOR], 1.58; 95% CI, 1.02-2.44; p = 0.04). Intravenous tirofiban was not significantly associated with an increased risk of sICH (12/175 [6.9%] vs. 11/207 [5.3%]; aOR, 1.41; 95% CI, 0.59-3.34; p = 0.44) or 90-day mortality (21/175 [12.0%] vs. 34/207 [16.4%]; aOR, 0.71; 95% CI, 0.38-1.31; p = 0.27).

INTERPRETATION

Among patients with acute intracranial LAA stroke and successful reperfusion following endovascular thrombectomy, adjunct intravenous tirofiban was associated with a higher rate of independent functional outcome, without higher rates of sICH or mortality. Confirmatory randomized trials in these patients are desirable.

Effect of mechanical thrombectomy with and without intravenous thrombolysis on the functional outcome of patients with different degrees of thrombus perviousness

PURPOSE

This study aimed to investigate the long-term functional outcome of patients with different degrees of thrombus perviousness (TP) undergoing mechanical thrombectomy alone and those undergoing combined intravenous thrombolysis (IVT) plus mechanical thrombectomy.

METHODS

We conducted a retrospective analysis of consecutive patients with acute ischemic stroke due to large vessel occlusion who underwent mechanical thrombectomy alone or bridging therapy between January 2016 and October 2020. TP was quantified by thrombus attenuation increase (TAI) on admission computed tomography angiography compared with non-contrast computed tomography. After dichotomization of TAI as higher or lower perviousness, Fisher exact tests were performed to estimate the associations of different therapies with favorable functional outcomes [Modified Ranking Scale score at 90 days (90-day mRS) of 0 to 2].

RESULTS

A total of 73 patients were included in our study. 35 (47.9%) thrombi were classified as higher-perviousness clots with TAI of ≥ 24 HU, and the other 38 thrombi were lower-perviousness clots. A favorable outcome with a 90-day mRS of 0 to 2 was observed in 32 patients. In patients with thrombi of lower perviousness, favorable outcome was more common in the bridging therapy group than in the thrombectomy-alone group (p = 0.013), whereas in patients with thrombi of higher perviousness, the long-term neurological outcome did not significantly differ between two therapy groups (p = 0.094).

CONCLUSION

Patients with thrombi of lower perviousness were recommended to undergo intravenous alteplase followed by endovascular thrombectomy, and those with thrombi of higher perviousness could undergo thrombectomy alone.

Intravenous thrombolysis upon flow restoration improves outcome in endovascular thrombectomy

BACKGROUND

We hypothesized that ongoing IV thrombolysis (IVT) at flow restoration in patients with acute ischemic stroke (AIS) treated with IVT and endovascular thrombectomy (ET) is associated with improved outcome.

METHODS

We included patients with IVT and successful recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b) after ET from an observational multicenter cohort, the German Stroke Registry - Endovascular Treatment trial. Procedural characteristics and functional outcome at discharge and 90 days were compared between patients with and without ongoing IVT at flow restoration. To determine associations with functional outcome, adjusted ORs were calculated using ordinal multivariable logistic regression models adjusted for potential baseline confounder variables.

RESULTS

Among 1303 patients treated with IVT and ET who achieved successful recanalization, IVT was ongoing in 13.8% (n=180) at flow restoration. Ongoing IVT was associated with better functional outcome at discharge (adjusted OR 1.61; 95% CI 1.13 to 2.30) and at 90 days (adjusted OR 1.52; 95% CI 1.06 to 2.18).

CONCLUSION

These results provide preliminary evidence for a benefit of ongoing IVT at flow restoration in patients with AIS treated with ET.

Improving the Reachability of Contact Aspiration for Acute Ischemic Stroke Using a New Delivery Assist Catheter

OBJECTIVE

This study aimed to improve the reachability of large lumen catheter for contact aspiration during acute ischemic stroke by a new delivery assist catheter.

METHODS

This study included 58 patients with large-vessel stroke treated using endovascular procedures at our institution and affiliated hospitals between July 2021 and January 2023. Contact aspiration, especially contact aspiration using nonpenetrating of thrombus (CANP) technique, was adopted as first-line thrombectomy for localized internal carotid artery, middle cerebral artery proximal (M1 segment), and basilar artery without tandem occlusion in acute stroke. The new delivery assist catheter (AXS Offset catheter, Stryker, Fremont, CA, USA) was standardized after its release. Results of this improved contact aspiration technique using the new delivery assist catheter, including reachability, procedure time, and first-pass effect, were compared with conventional catheters.

RESULTS

Of the 58 patients, 43 underwent only thrombectomy for acute embolic stroke. CANP technique was attempted on 25 patients (25/43, 58.1%). Of these, a normal inner catheter (inner diameter: 0.021 or 0.027 inches) and the new delivery assist catheter were used on 10 (10/25, 40%) and 15 (15/25, 60%) patients, respectively. An aspiration catheter reached the thrombus for 5 patients (5/10, 50%) and 14 patients (14/15 93.3%) in the normal and new delivery assist catheter groups, respectively (P = 0.023). There was no significant difference in the results of contact aspiration due to the delivery catheter.

CONCLUSIONS

The new delivery assist catheter improved the reachability of the aspiration catheter to the thrombus and is an effective device for performing CANP technique.

Microvascular reperfusion during endovascular therapy: the balance of supply and demand

BACKGROUND

Endovascular therapy (EVT) has revolutionized the treatment of acute stroke, but large vessel recanalization does not always result in tissue-level reperfusion. Cerebral blood flow (CBF) is not routinely monitored during EVT. We aimed to leverage diffuse correlation spectroscopy (DCS), a novel transcranial optical imaging technique, to assess the relationship between microvascular CBF and post-EVT outcomes.

METHODS

Frontal lobe CBF was monitored by DCS in 40 patients undergoing EVT. Baseline CBF deficit was calculated as the percentage of CBF impairment on pre-EVT CT perfusion. Microvascular reperfusion was calculated as the percentage increase in DCS-derived CBF that occurred with recanalization. The adequacy of reperfusion was defined by persistent CBF deficit, calculated as: baseline CBF deficit - microvascular reperfusion. A good functional outcome was defined as 90-day modified Rankin Scale score ≤2.

RESULTS

Thirty-six of 40 patients achieved successful recanalization, in whom microvascular reperfusion in itself was not associated with infarct volume or functional outcome. However, patients with good functional outcomes had a smaller persistent CBF deficit (median 1% (IQR -11%-16%)) than patients with poor outcomes (median 28% (IQR 2-50%)) (p=0.02). Smaller persistent CBF deficit was also associated with smaller infarct volume (p=0.004). Multivariate models confirmed that persistent CBF deficit was independently associated with infarct volume and functional outcome.

CONCLUSIONS

CBF augmentation alone does not predict post-EVT outcomes, but when microvascular reperfusion closely matches the baseline CBF deficit, patients experience favorable clinical and radiographic outcomes. By recognizing inadequate reperfusion, bedside CBF monitoring may provide opportunities to personalize post-EVT care aimed at CBF optimization.

Intravenous alteplase before endovascular therapy for acute large vessel occlusion with large ischemic core: subanalysis of a randomized clinical trial

BACKGROUND

The efficacy of endovascular therapy (EVT) in patients with large ischemic core has been reported, but it remains unclear whether IV alteplase (IVT) has beneficial effects in addition to EVT in such patients. We evaluated the efficacy and safety of EVT with or without IVT.

METHODS

The RESCUE-Japan LIMIT was an open-label, prospective, multicenter, randomized clinical trial to evaluate the efficacy and safety of EVT in stroke patients with large ischemic core, defined as Alberta Stroke Program Early CT Score (ASPECTS) 3-5. This subanalysis evaluated the differences in the effects of EVT with medical care (EVT group) compared with medical care alone (No-EVT group) between those who received IVT (IVT stratum) and those who did not (No-IVT stratum) before EVT.

RESULTS

Among 202 enrolled patients, 147 (73%) did not receive IVT. In the No-IVT stratum, the modified Rankin Scale (mRS) score of 0-3 at 90 days was significantly higher in the EVT group than in the No-EVT group (31.1% vs 12.3%, OR 3.21 (95% CI 1.37 to 7.53)). In the IVT stratum, the mRS score of 0-3 was 30.8% in the EVT group and 13.8% in the No-EVT group (OR 2.78 (95% CI 0.72 to 10.7)) (interaction p=0.77). The incidence of symptomatic intracranial hemorrhage was not different between the two groups in the No-IVT stratum (OR 1.20 (95% CI 0.35 to 4.12)), but it was significantly higher in the EVT group than in the No-EVT group in the IVT stratum (11.5% vs 0%, p=0.03).

CONCLUSIONS

There was no difference in efficacy of EVT with or without IVT, while IVT before EVT might increase symptomatic intracranial hemorrhage in patients with large ischemic core.

TRIAL REGISTRATION INFORMATION

NCT03702413.

Blood Oxygenation Level-Dependent Cerebrovascular Reactivity-Derived Steal Phenomenon May Indicate Tissue Reperfusion Failure After Successful Endovascular Thrombectomy

In acute ischemic stroke due to large-vessel occlusion (LVO), the clinical outcome after endovascular thrombectomy (EVT) is influenced by the extent of autoregulatory hemodynamic impairment, which can be derived from blood oxygenation level-dependent cerebrovascular reactivity (BOLD-CVR). BOLD-CVR imaging identifies brain areas influenced by hemodynamic steal. We sought to investigate the presence of steal phenomenon and its relationship to DWI lesions and clinical deficit in the acute phase of ischemic stroke following successful vessel recanalization.From the prospective longitudinal IMPreST (Interplay of Microcirculation and Plasticity after ischemic Stroke) cohort study, patients with acute ischemic unilateral LVO stroke of the anterior circulation with successful endovascular thrombectomy (EVT; mTICI scale ≥ 2b) and subsequent BOLD-CVR examination were included for this analysis. We analyzed the spatial correlation between brain areas exhibiting BOLD-CVR-associated steal phenomenon and DWI infarct lesion as well as the relationship between steal phenomenon and NIHSS score at hospital discharge.Included patients (n = 21) exhibited steal phenomenon to different extents, whereas there was only a partial spatial overlap with the DWI lesion (median 19%; IQR, 8-59). The volume of steal phenomenon outside the DWI lesion showed a positive correlation with overall DWI lesion volume and was a significant predictor for the NIHSS score at hospital discharge.Patients with acute ischemic unilateral LVO stroke exhibited hemodynamic steal identified by BOLD-CVR after successful EVT. Steal volume was associated with DWI infarct lesion size and with poor clinical outcome at hospital discharge. BOLD-CVR may further aid in better understanding persisting hemodynamic impairment following reperfusion therapy.

Temporal progression of functional independence after mechanical thrombectomy in acute vertebrobasilar artery occlusions

BACKGROUND

Neurological recovery after endovascular treatment (EVT) for large vessel occlusion stroke often has diverse timelines. Understanding the temporal progression of functional independence after EVT, especially delayed functional independence (DFI) and highly delayed functional independence (HDFI), in patients who do not improve early is essential for prognostication and rehabilitation. We aimed to analyze the prevalence and predictors of DFI and HDFI after EVT in acute vertebrobasilar artery occlusions (VBAO).

METHODS

Patients with VBAO who received EVT in China were retrospectively enrolled. Early functional independence (EFI) was defined as a modified Rankin Scale (mRS) score of 0-2 at discharge. The incidence and predictors of DFI (mRS score 0-2 at 90 days in non-EFI patients) and HDFI (mRS score 0-2 at 1 year in non-DFI patients) were analyzed.

RESULTS

2422 patients met the study criteria. EFI was observed in 20% (483) of patients. Among non-EFI patients, DFI was observed in 21% (395/1880). HDFI was observed in 13% (191/1439) of non-DFI patients. Younger age (P=0.006), lower pre-EVT National Institutes of Health Stroke Scale (NIHSS) score (P<0.001), higher posterior circulation-Alberta Stroke Program Early CT Score (PC-ASPECTS) (P=0.012), and absence of symptomatic intracranial hemorrhage (sICH) (P<0.001) were predictors of DFI. Predictors of HDFI were younger age (P<0.001) and lower pre-EVT NIHSS score (P<0.001).

CONCLUSION

A considerable proportion of patients have DFI and HDFI. The independent predictors of DFI were younger age, lower pre-EVT NIHSS score, higher PC-ASPECTS, and absence of sICH. Predictors of HDFI included younger age and lower pre-EVT NIHSS score.

Effect of edaravone on symptomatic intracranial hemorrhage in patients with acute large vessel occlusion on apixaban for non-valvular atrial fibrillation

BACKGROUND

Edaravone administration was associated with lower incidence of symptomatic intracranial hemorrhage (sICH) in patients with acute large vessel occlusion (LVO). However, its protective effect on sICH in patients with LVO who receive direct oral anticoagulants for non-valvular atrial fibrillation (NVAF) is uncertain.

OBJECTIVES

To explore the effect of edaravone administration on the incidence of sICH in patients with acute LVO receiving apixaban for NVAF.

METHODS

A Japanese multicenter registry of apixaban on clinical outcome of the patients with LVO or stenosis (ALVO study) included patients who were admitted within 24 h after stroke onset and were received apixaban within 14 days of stroke onset. Patients were divided into two groups according to edaravone administration (Edaravone and No-Edaravone groups). The incidence of sICH within one year and infarct growth before apixaban administration were compared between these groups.

RESULTS

Of the 686 enrolled patients, 622 were included and edaravone was administered to 407 (65.4%). The incidences of sICH in Edaravone and No-Edaravone groups were 1.3% and 5.0%, respectively (p = 0.01). The inverse probability of treatment-weighting (IPTW) hazard ratio (HR) (95% confidence interval [CI]) of Edaravone group for sICH within one year was 0.36 (0.15-0.80) compared to No-Edaravone group. The incidences of infarct growth in Edaravone and No-Edaravone groups were 35.3% and 42.0%, respectively (p = 0.13). IPTW HR (95% CIs) for infarct growth was 0.76 (0.60-0.97).

CONCLUSIONS

Edaravone administration was associated with a lower incidence of sICH in patients with LVO and NVAF who administrated apixaban.

Using deep learning for an automatic detection and classification of the vascular bifurcations along the Circle of Willis

Most of the intracranial aneurysms (ICA) occur on a specific portion of the cerebral vascular tree named the Circle of Willis (CoW). More particularly, they mainly arise onto fifteen of the major arterial bifurcations constituting this circular structure. Hence, for an efficient and timely diagnosis it is critical to develop some methods being able to accurately recognize each Bifurcation of Interest (BoI). Indeed, an automatic extraction of the bifurcations presenting the higher risk of developing an ICA would offer the neuroradiologists a quick glance at the most alarming areas. Due to the recent efforts on Artificial Intelligence, Deep Learning turned out to be the best performing technology for many pattern recognition tasks. Moreover, various methods have been particularly designed for medical image analysis purposes. This study intends to assist the neuroradiologists to promptly locate any bifurcation presenting a high risk of ICA occurrence. It can be seen as a Computer Aided Diagnosis scheme, where the Artificial Intelligence facilitates the access to the regions of interest within the MRI. In this work, we propose a method for a fully automatic detection and recognition of the bifurcations of interest forming the Circle of Willis. Several neural networks architectures have been tested, and we thoroughly evaluate the bifurcation recognition rate.

Endovascular Thrombectomy Outcomes with and without Intravenous Thrombolysis for Large Ischemic Cores Identified with CT or MRI

Background Whether intravenous thrombolysis (IVT) prior to endovascular thrombectomy (EVT) provides additional benefits in patients with acute ischemic stroke (AIS) and a large infarct core (LIC) remains unclear. Purpose To examine whether treatment with IVT before EVT is beneficial in patients with LIC identified with CT or MRI (Alberta Stroke Program Early CT score 0-5). Materials and Methods This retrospective study included consecutive adult patients diagnosed with AIS due to large vessel occlusion (LVO) and LIC treated with EVT who were enrolled in the ETIS (Endovascular Treatment in Ischemic Stroke) Registry in France between January 2015 and January 2022. The primary outcome measure was a favorable outcome (modified Rankin Scale [mRS] score 0-3) at 90 days. Secondary outcomes included functional independence (mRS score 0-2) at 90 days, improvement in degree of disability (ordinal shift in mRS score toward a better outcome) at 90 days, early neurologic improvement at 24 hours, and successful reperfusion (modified Thrombolysis in Cerebral Infarction score of 2b or higher). Safety outcomes included symptomatic intracerebral hemorrhage within 24 hours and mortality at 90 days. Inverse probability of treatment weighting (IPTW)-adjusted analysis was used to assess the treatment effect of IVT adjusted for baseline variables. Results Of 1408 patients (mean age, 68.3 years ± 15.4 [SD]; 789 men), 654 (46.4%) were treated with IVT prior to EVT. In the IPTW-adjusted data set, IVT plus EVT was associated with a higher rate of favorable outcome at 90 days (odds ratio [OR], 1.24 [95% CI: 1.05, 1.46]; P = .01), functional independence at 90 days (OR, 1.47 [95% CI: 1.22, 1.77]; P < .001), improvement in degree of disability at 90 days (common OR, 1.30 [95% CI: 1.13, 1.49]; P < .001), early neurologic improvement (OR, 1.26 [95% CI: 1.07, 1.49]; P = .005), and successful reperfusion (OR, 1.43 [95% CI: 1.14, 1.79]; P = .002) than EVT alone. Rates of brain hemorrhage within 24 hours and mortality at 90 days were similar between groups. Conclusion In patients with AIS due to LVO with LIC identified with CT or MRI, treatment with IVT before EVT appeared to provide a clinical benefit over EVT alone. Clinical trial registration no. NCT03776877 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Kallmes and Rabinstein in this issue.

Good collaterals and better outcomes after EVT for basilar artery occlusion: A systematic review and meta-analysis

BACKGROUND

Stroke caused by acute basilar artery occlusion (BAO) is devastating with high dependency and mortality. Recent trials have demonstrated the efficacy of endovascular treatment (EVT) for acute BAO, while pretreatment collaterals may be a valuable prognostic indicator for post-EVT outcomes.

AIMS

To systematically review and synthesize evidence on the associations between pretreatment collateral status and outcomes after EVT in acute BAO.

METHODS

We retrieved relevant full-text articles published in English since 1 January 2010, reporting associations between pretreatment collateral status and outcomes after EVT for BAO, by searching MEDLINE and Embase. The primary outcome was favorable or good 90-day functional outcome (modified Rankin Scale [mRS] 0-2 or 0-3); secondary outcomes included successful recanalization, symptomatic intracranial hemorrhage, final infarct volume, and 90-day mortality. Risk ratios (RRs) with 95% confidence intervals (CIs) for good versus poor collaterals on the outcomes were synthesized using random-effects models. Subgroup and sensitivity analyses were conducted for the primary outcome.

RESULTS

Overall, 29 primary studies (2995 participants) were included in qualitative review, among which 16 studies (1447 participants) were meta-analyzed. With different imaging modalities and methods to grade the collateral status, good collaterals were found in 33-85% of patients in the individual primary studies (I2 = 95.2%, p < 0.001), with a pooled proportion of 51% (95% CI: 40-62%) across all studies. Good pretreatment collaterals were associated with a doubled rate of favorable/good 90-day functional outcome (RR = 2.03, 95% CI: 1.63-2.51, p < 0.001), a higher rate of successful recanalization (RR = 1.23, 95% CI: 1.04-1.45, p = 0.015), and reduced 90-day mortality (RR = 0.59, 95% CI: 0.43-0.81, p = 0.001) after EVT for BAO. None of the primary studies reported the associations of good collaterals with the other secondary outcomes. Subgroup analyses revealed possibly more prominent protective effect of good pretreatment collaterals over the primary outcome, in studies with longer time windows in patient eligibility criteria for EVT (p = 0.028 for between-subgroup heterogeneity).

CONCLUSIONS

In patients with BAO receiving EVT, good pretreatment collateral status was associated with a higher chance of favorable 90-day functional outcome, despite the various methods in grading the collateral circulation. Efforts are needed for more standardized collateral assessment in BAO, for more reliable and generalizable investigations of its clinical implications.

High-resolution magnetic resonance imaging of acute intracranial artery thrombus

BACKGROUND AND PURPOSE

The development of high-resolution magnetic resonance imaging (HR-MRI) has enabled submillimeter-level evaluation of intracranial artery plaque and luminal thrombus. We sought to investigate the value of HR-MRI in assessing the pathogenesis of acute intracranial artery thrombus.

METHODS

We examined the presence of intracranial thrombus on three-dimensional T1-weighted HR-MRI in acute ischemic stroke patients with intracranial artery occlusion on magnetic resonance angiography. We defined two thrombus-related HR-MRI features (peri-thrombus plaque and distal residual flow beyond the thrombus) and analyzed their association with potential embolic sources.

RESULTS

Luminal thrombus and a shrunken artery without luminal thrombus were detected in 162 (96.4%) and six (3.6%) of 168 patients with intracranial artery occlusion, respectively. Among 111 patients with culprit major artery thrombus, peri-thrombus plaques were observed in 46.8% and distal residual flow beyond the thrombus in 64.0%. Patients with peri-thrombus plaque had a higher prevalence of diabetes (44.2% vs. 25.4%; p = 0.037), a lower prevalence of potential sources of cardioembolism (0% vs. 16.9%; p = 0.002), and a nonsignificantly lower prevalence of potential embolic sources from extracranial arteries (9.6% vs. 20.3%; p = 0.186) than those without. Patients with distal residual flow beyond the thrombus had a lower prevalence of potential sources of cardioembolism (1.4% vs. 22.5%; p < 0.001) and smaller infarct volumes (5.0 [1.4-12.7] mL vs. 16.6 [2.4-94.6] mL; p = 0.012) than those without.

CONCLUSIONS

Our study showed that HR-MRI helps clarify the pathogenesis of acute intracranial artery thrombus. The presence of peri-thrombus plaque and distal residual flow beyond the thrombus favor the stroke mechanism of atherosclerosis rather than cardioembolism.

Combined technique as first approach in mechanical thrombectomy: Efficacy and safety of REACT catheter combined with stent retriever

INTRODUCTION

Mechanical thrombectomy (MT) with combined treatment including both a stent retriever and distal aspiration catheter may improve recanalization rates in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Here, we evaluated the effectiveness and safety of the REACT aspiration catheter used with a stent retriever.

METHODS

This prospective study included consecutive adult patients who underwent MT with a combined technique using REACT 68 and/or 71 between June 2020 and July 2021. The primary endpoints were final and first pass mTICI 2b-3 and mTICI 2c-3 recanalization. Analysis was performed after first pass and after each attempt. Secondary safety outcomes included procedural complications, symptomatic intracranial hemorrhage (sICH) at 24 h, in-hospital mortality, and 90-day functional independence (modified Rankin Scale [mRS] 0-2).

RESULTS

A total of 102 patients were included (median age 78; IQR: 73-87; 50.0% female). At baseline, median NIHSS score was 19 (IQR: 11-21), and ASPECTS was 9 (IQR: 8-10). Final mTICI 2b-3 recanalization was achieved in 91 (89.2%) patients and mTICI 2c-3 was achieved in 66 (64.7%). At first pass, mTICI 2b-3 was achieved in 55 (53.9%) patients, and mTICI 2c-3 in 37 (36.3%). The rate of procedural complications was 3.9% (4/102), sICH was 6.8% (7/102), in-hospital mortality was 12.7% (13/102), and 90-day functional independence was 35.6% (36/102).

CONCLUSION

A combined MT technique using a stent retriever and REACT catheter resulted in a high rate of successful recanalization and first pass recanalization in a sample of consecutive patients with AIS due to LVO in clinical use.

Predictive Value of a Novel Baseline Diffusion-Weighted Imaging Posterior Circulation Score in Endovascular Treatment of Patients with Acute Vertebrobasilar Occlusion

RATIONALE AND OBJECTIVES

To investigate the predictive value of a novel posterior circulation score (novel-PC score) based on baseline posterior circulation diffusion-weighted imaging (DWI) for functional independence after endovascular treatment (EVT) in patients with acute vertebral-basilar artery occlusion (VBAO).

MATERIALS AND METHODS

The baseline DWI brain stem score (BSS), posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS), and the novel-PC score were evaluated separately. A modified Rankin scale (mRS) ≤2 at 90 days was defined as a prognostic indicator of functional independence. Modified Thrombolysis in Cerebral Infarction grade 2b or 3 was defined as surgical success.

RESULTS

A total of 64 eligible patients were enrolled and divided into good and poor functional prognosis groups based on the mRS. The novel-PC score, BSS, and pc-ASPECTS (all P ≤ .001) were significantly better in the good functional prognosis group. The novel-PC score had a higher predictive value than BSS and pc-ASPECTS for 90-day functional independence (area under the receiver operating characteristic curve, 0.87 vs. 0.73 vs. 0.71; P < .05). Univariate binary logistic regression analysis showed that age (P = .006), Posterior National Institutes of Health Stroke Scale ≤18 (P < .001), BSS ≤2 (P = .008), pc-ASPECTS >7 (P = .002), and novel-PC score ≤5 (P = .001) were independently associated with function.

CONCLUSION

Our novel-PC score, based on DWI, can independently predict functional prognosis in patients with acute VBAO after EVT.

CLINICAL RELEVANCE

The novel-PC score based on baseline DWI was shown to be an independent predictor of function in patients with acute BVAO who are treated with EVT.

Comparison of Thrombolysis In Cerebral Infarction (TICI) 2b and TICI 3 reperfusion in endovascular therapy for large ischemic anterior circulation strokes

BACKGROUND

Landmark thrombectomy trials have provided evidence that selected patients with large ischemic stroke benefit from successful endovascular therapy, commonly defined as incomplete (modified Thrombolysis In Cerebral Infarction (mTICI) 2b) or complete reperfusion (mTICI 3). We aimed to investigate whether mTICI 3 improves functional outcomes compared with mTICI 2b in large ischemic strokes.

METHODS

This retrospective multicenter cohort study was conducted to compare mTICI 2b versus mTICI 3 in large ischemic strokes in the anterior circulation. Patients enrolled in the German Stroke Registry between 2015-2021 were analyzed. Large ischemic stroke was defined as an Alberta Stroke Program Early CT Score (ASPECTS) of 3-5. Patients were matched by final mTICI grade using propensity score matching. Primary outcome was the 90-day modified Rankin Scale (mRS) score.

RESULTS

After matching, 226 patients were included. Baseline and imaging characteristics were balanced between mTICI 2b and mTICI 3 patients. There was no shift on the mRS favoring mTICI 3 compared with mTICI 2b in large ischemic strokes (adjusted common odds ratio (acOR) 1.12, 95% confidence interval (95% CI) 0.64 to 1.94, P=0.70). The rate of symptomatic intracranial hemorrhage was higher in mTICI 2b than in mTICI 3 patients (12.6% vs 4.5%, P=0.03). Mortality at 90 days did not differ between mTICI 3 and mTICI 2b (33.6% vs 37.2%; adjusted OR 0.69, 95% CI 0.33 to 1.45, P=0.33).

CONCLUSIONS

In endovascular therapy for large ischemic strokes, mTICI 3 was not associated with better 90-day functional outcomes compared with mTICI 2b. This study suggests that mTICI 2b might be warranted as the final angiographic result, questioning the benefit/risk ratio of additional maneuvers to seek for mTICI 3 in large ischemic strokes.

TRIAL REGISTRATION NUMBER

NCT03356392.

Higher Procedural Volumes Are Associated with Faster Treatment Times, Better Functional Outcomes, and Lower Mortality in Patients Undergoing Endovascular Treatment for Acute Ischemic Stroke

OBJECTIVE

We aimed to characterize the association of hospital procedural volumes with outcomes among acute ischemic stroke (AIS) patients undergoing endovascular therapy (EVT).

METHODS

This was a retrospective, observational cohort study using data prospectively collected from January 1, 2016 to December 31, 2019 in the Get with the Guidelines-Stroke registry. Participants were derived from a cohort of 60,727 AIS patients treated with EVT within 24 hours at 626 hospitals. The primary cohort excluded patients with pretreatment National Institutes of Health Stroke Scale (NIHSS) < 6, onset-to-treatment time > 6 hours, and interhospital transfers. There were 2 secondary cohorts: (1) the EVT metrics cohort excluded patients with missing data on time from door to arterial puncture and (2) the intravenous thrombolysis (IVT) metrics cohort only included patients receiving IVT ≤4.5 hours after onset.

RESULTS

The primary cohort (mean ± standard deviation age = 70.7 ± 14.8 years; 51.2% female; median [interquartile range] baseline NIHSS = 18.0 [13-22]; IVT use, 70.2%) comprised 21,209 patients across 595 hospitals. The EVT metrics cohort and IVT metrics cohort comprised 47,262 and 16,889 patients across 408 and 601 hospitals, respectively. Higher procedural volumes were significantly associated with higher odds (expressed as adjusted odds ratio [95% confidence interval] for every 10-case increase in volume) of discharge to home (1.03 [1.02-1.04]), functional independence at discharge (1.02 [1.01-1.04]), and lower rates of in-hospital mortality (0.96 [0.95-0.98]). All secondary measures were also associated with procedural volumes.

INTERPRETATION

Among AIS patients primarily presenting to EVT-capable hospitals (excluding those transferred from one facility to another and those suffering in-hospital strokes), EVT at hospitals with higher procedural volumes was associated with faster treatment times, better discharge outcomes, and lower rates of in-hospital mortality. ANN NEUROL 2023.