Effect of Mechanical Thrombectomy Without vs With Intravenous Thrombolysis on Functional Outcome Among Patients With Acute Ischemic Stroke: The SKIP Randomized Clinical Trial

Utility of tPA Administration in Acute Treatment of Internal Carotid Artery Occlusions

Background

Intravenous tissue plasminogen activator (IV-tPA) remains part of the guidelines for acute ischemic stroke treatment, yet internal carotid artery occlusions (ICAO) are known to be poorly responsive to IV-tPA. It is unknown whether bridging thrombolysis (BT) is beneficial in such cases.

Purpose

We sought to evaluate whether the use of IV-tPA improved overall clinical outcomes in patients undergoing endovascular thrombectomy (EVT) for ICA occlusions.

Methods

Data from 1367 consecutive stroke cases treated with EVT from 2012-2019 were prospectively collected from a single center. Univariate and multivariate logistic regression were used to assess the relationship between IV-tPA administration and clinical outcome.

Results

153 patients were found to have carotid terminus and tandem ICAO who received EVT and presented within 4.5h of last seen well. 50% (n = 82) received IV tPA. There were no differences between the groups with respect to age, NIHSS, time to EVT and ASPECTS score. 53% had tandem ICA-MCA occlusions. Rate of recanalization (≥ TICI 2B) and sICH did not significantly differ between the two groups. Regression analysis demonstrated no effect of IV-tPA on modified Rankin Score (mRS) at 90 days and overall mortality. Factors significantly associated with reduced mortality included lower age, lower NIHSS, and better rate of recanalization.

Conclusions

There was no significant difference in clinical outcomes in those receiving BT vs. direct EVT for ICAO. For centers with optimal door-to-puncture times, bypassing IV-tPA may expedite recanalization times and potentially yield more favorable outcomes. Patients with higher NIHSS and tandem lesions may have better outcomes with BT.

Cost-effectiveness analysis of endovascular treatment with or without intravenous thrombolysis in acute ischemic stroke

OBJECTIVE

Intravenous (IV) recombinant tissue plasminogen activator (r-tPA) may not provide additional benefit in terms of functional outcomes in patients with acute ischemic stroke (AIS) who undergo endovascular treatment (EVT). In this context, the cost-effectiveness of EVT alone compared with its application following IV r-tPA has not been evaluated.

METHODS

The authors determined the average rates of death or disability in each of the two treatment groups from four randomized clinical trials that enrolled patients with AIS within 4.5 hours of symptom onset and randomly assigned patients to EVT alone and IV r-tPA and EVT. By using three sources derived from previous studies, the authors determined the cost of IV r-tPA, cost of staff time for administration, cost of the EVT, cost of hospital stay, costs of supported discharge and community care, and cost of posthospitalization care and disability. They then assessed the cost-effectiveness of EVT alone using a decision tree for the 1st year after AIS and a Markov model with a 10-year horizon, including probabilistic assessment by Monte Carlo simulations.

RESULTS

The 1-year cost was higher with IV r-tPA and EVT compared with EVT alone (incremental cost ranging between $3554 and $13,788 per patient). The mean incremental cost-effectiveness ratios (ICERs) were -$1589, -$78,327, and -$15,471 per quality-adjusted life-year gained for cost sources 1, 2, and 3, respectively, for EVT alone compared with IV r-tPA and EVT at 10 years. The ceiling ICER (willingness to pay) for a probability of 100% that EVT alone was more cost-effective ranged between $25,000 and $100,000 in the three models.

CONCLUSIONS

EVT alone appears to be more cost-effective compared with EVT and IV r-tPA for the treatment of AIS patients presenting within 4.5 hours of symptom onset.

Effect of intravenous thrombolysis before endovascular therapy on outcome according to collateral status: insight from the ETIS Registry

BACKGROUND

It is unknown whether collateral status modifies the effect of pretreatment intravenous thrombolysis (IVT) on the outcomes of patients with large vessel occlusions treated with endovascular therapy (EVT). We aimed to assess whether collateral status modifies the effect of IVT on the outcomes of EVT in clinical practice.

METHODS

We used data from the ongoing prospective multicentric Endovascular Treatment in Ischemic Stroke (ETIS) Registry in France. Patients with anterior circulation proximal large vessel occlusions treated with EVT within 6 hours of symptom onset were enrolled. Patients were divided into two groups based on pretreatment with IVT. The two groups were matched based on baseline characteristics. We tested the interaction between collateral status and IVT in unadjusted and adjusted models.

RESULTS

A total of 1589 patients were enrolled in the study, of whom 55% received IVT. Using a propensity score matching method, 724 no IVT patients were matched to 549 IVT patients. In propensity score weighted analysis, IVT was associated with higher odds of early neurological improvement (OR 1.74; 95% CI 1.33 to 2.26), favorable functional outcome (OR 1.66; 95% CI 1.23 to 2.24), excellent functional outcome (OR 2.04; 95% CI 1.47 to 2.83), and successful reperfusion (OR 2.18; 95% CI 1.51 to 3.16). IVT was not associated with mortality or hemorrhagic complications. There was no interaction between collateral status and IVT association with any of the outcomes.

CONCLUSIONS

Collateral status does not modify the effect of pretreatment IVT on the efficacy and safety outcomes of EVT.

Predicting functional outcome in acute ischemic stroke patients after endovascular treatment by machine learning

Background

Endovascular therapy (EVT) was the standard treatment for acute ischemic stroke with large vessel occlusion. Prognosis after EVT is always a major concern. Here, we aimed to explore a predictive model for patients after EVT.

Method

A total of 156 patients were retrospectively enrolled. The primary outcome was functional dependence (defined as a 90-day modified Rankin Scale score ≤ 2). Least absolute shrinkage and selection operator and univariate logistic regression were used to select predictive factors. Various machine learning algorithms, including multivariate logistic regression, linear discriminant analysis, support vector machine, k-nearest neighbors, and decision tree algorithms, were applied to construct prognostic models.

Result

Six predictive factors were selected, namely, age, baseline National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early CT (ASPECT) score, modified thrombolysis in cerebral infarction score, symptomatic intracerebral hemorrhage (sICH), and complications (pulmonary infection, gastrointestinal bleeding, and cardiovascular events). Based on these variables, various models were constructed and showed good discrimination. Finally, a nomogram was constructed by multivariate logistic regression and showed a good performance.

Conclusion

Our nomogram, which was composed of age, baseline NIHSS score, ASPECT score, recanalization status, sICH, and complications, showed a very good performance in predicting outcome after EVT.

Intravenous Thrombolysis for Acute Ischemic Stroke in Patients with End-Stage Renal Disease on Hemodialysis: A Narrative Review

OBJECTIVES

Acute ischemic stroke (AIS) is a significant and devastating complication in patients with end-stage renal disease on hemodialysis (ESRD/HD). Since one-third of AIS in ESRD/HD patients occurs during or soon after dialysis, patients are more likely to present within the time window when intravenous thrombolysis (IVT) can be performed. IVT may improve prognosis in ESRD/HD patients with AIS. However, ESRD/HD patients have been excluded from large trials and may have been withheld from IVT due to concerns about bleeding complications. To date, there is no clear evidence and firm guidance on the safety and efficacy of IVT in ESRD/HD patients with AIS. This narrative review aimed to evaluate critical scientific data on the benefits and risks of IVT use in patients with ESRD/HD and AIS.

MATERIALS AND METHODS

We searched the electronic database of PubMed for studies evaluating the relationship between AIS, ESRD/HD, and IVT. Reference sections and additional publications were also searched manually. Studies on AIS in patients with ESRD/HD requiring maintenance dialysis that referred to IVT were included.

RESULTS

In total, 560 studies were found in the PubMed electronic database during the period covered, of which 10 met the selection criteria. IVT for AIS in ESRD/HD patients could improve neurological outcomes and be safely performed even with the possibility of hemorrhagic complications associated with hypertension. Despite the high complication and mortality rates in ESRD/HD patients with AIS after IVT, the association with IVT was unclear.

CONCLUSIONS

IVT for AIS in ESRD/HD patients may improve outcomes and should not be withheld based solely on ESRD/HD status.

Acute ischaemic stroke: recent advances in reperfusion treatment

During the last 5–7 years, tremendous progress was achieved in the reperfusion treatment of acute ischaemic stroke during its first few hours from symptom onset. This review summarizes the latest evidence from randomized clinical trials and prospective registries with a focus on endovascular treatment using stent retrievers, aspiration catheters, thrombolytics, and (in selected patients) carotid stenting. Novel approaches in prehospital (mobile interventional stroke teams) and early hospital (direct transfer to angiography) management are described, and future perspectives (‘all-in-one’ laboratories with angiography and computed tomography integrated) are discussed. There is reasonable chance for patients with moderate-to-severe acute ischaemic stroke to survive without permanent sequelae when the large-vessel occlusion is removed by means of modern pharmaco-mechanic approach. Catheter thrombectomy is now the golden standard of acute stroke treatment. The role of cardiologists in stroke is expanding from diagnostic help (to reveal the cause of stroke) to acute therapy in those regions where such up-to-date Class I. A treatment is not yet available.

Research progress on the role of hormones in ischemic stroke

Ischemic stroke is a major cause of death and disability around the world. However, ischemic stroke treatment is currently limited, with a narrow therapeutic window and unsatisfactory post-treatment outcomes. Therefore, it is critical to investigate the pathophysiological mechanisms following ischemic stroke brain injury. Changes in the immunometabolism and endocrine system after ischemic stroke are important in understanding the pathophysiological mechanisms of cerebral ischemic injury. Hormones are biologically active substances produced by endocrine glands or endocrine cells that play an important role in the organism's growth, development, metabolism, reproduction, and aging. Hormone research in ischemic stroke has made very promising progress. Hormone levels fluctuate during an ischemic stroke. Hormones regulate neuronal plasticity, promote neurotrophic factor formation, reduce cell death, apoptosis, inflammation, excitotoxicity, oxidative and nitrative stress, and brain edema in ischemic stroke. In recent years, many studies have been done on the role of thyroid hormone, growth hormone, testosterone, prolactin, oxytocin, glucocorticoid, parathyroid hormone, and dopamine in ischemic stroke, but comprehensive reviews are scarce. This review focuses on the role of hormones in the pathophysiology of ischemic stroke and discusses the mechanisms involved, intending to provide a reference value for ischemic stroke treatment and prevention.

Intravenous thrombolysis before thrombectomy in acute ischemic stroke: a dual centre retrospective cohort study

First pass effect (FPE) is a successful recanalization (mTICI ≥ 2b) after the first trial of thrombectomy. It is associated with good functional outcomes. Few studies discussed the effect of BT (bridging therapy: combined I.V. thrombolysis and mechanical thrombectomy) on FPE and clinical outcomes. In our study, we would like to report the effect of MT with or without preceding IVT on FPE and the functional outcome of AIS (Acute Ischemic Stroke) of anterior circulation in real practice. A dual-center retrospective cohort study enrolled 201 patients with AIS of anterior circulation and was divided into a bridging therapy (BT) group of 150 patients who received alteplase preceding thrombectomy, and a direct mechanical thrombectomy (dMT) group of 51 patients. Comparisons between both groups regarding the clinical and radiological outcome. Early better clinical outcome (mRS ≤ 2) at day seven with BT group (39.3%) rather than dMT (23.5%) with P value = 0.044. No significant differences as regard puncture to revascularization time, successful revascularization (mTICI) ≥ 2b and FPE between both groups (P value: 0.328, 0.538, and 0.708, respectively). No differences as regards hemorrhagic transformation, mortality rate, and 90-day favorable outcome between both groups (P value 0.091, 0.089, and 0.192, respectively). BT might have better early outcome than dMT but no difference as regards 90-day favorable outcomes, mortality, sICH, FPE, recanalization rate and procedure time. It might be reasonable to go directly to mechanical thrombectomy without IVT for AIS with large vessel occlusion.

National Institutes of Health Stroke Scale Score Less Than 10 at 24 hours After Stroke Onset Is a Strong Predictor of a Favorable Outcome After Mechanical Thrombectomy

BACKGROUND

There are a few accurate predictors of patient outcomes after mechanical thrombectomy (MT).

OBJECTIVE

To investigate whether the National Institutes of Health Stroke Scale (NIHSS) score 24 hours after stroke onset could predict favorable outcomes at 90 days in patients with acute stroke treated with MT.

METHODS

Patients from the SKIP study were enrolled in this study. Using receiver operating characteristic curves, the optimal cut-off NIHSS score 24 hours after stroke onset was calculated to distinguish between favorable (modified Rankin Scale score 0-2) and unfavorable (modified Rankin Scale score 3-6) outcomes at 90 days. These receiver operating characteristic curves were compared with those of previously reported predictors of favorable outcomes, such as the ΔNIHSS score (baseline NIHSS score-NIHSS score at 24 h), percent delta (ΔNIHSS score × 100/baseline NIHSS score), and early neurological improvement indices.

RESULTS

A total of 177 patients (median age, 72 years; female, 65 [37%]) were enrolled, and 109 (61.9%) had favorable outcomes. The respective sensitivity, specificity, and area under the curve values for an NIHSS of 10 were 92.6%, 80.7%, and .906; a ΔNIHSS score of 7 were 70.6%, 76.1%, and .797; and percent delta of 48.3% were 85.3%, 80.7%, and .890.

CONCLUSION

NIHSS score <10 at 24 hours after stroke onset is a strong predictor of favorable outcomes at 90 days in patients treated with MT.

Clinical Outcomes of Extracranial Carotid Artery-Related Stroke Eligible for Mechanical Reperfusion on Top of Per-Guidelines Thrombolytic Therapy: Analysis from a 6-Month Consecutive Patient Sample in 2 Centers

BACKGROUND Systemic intravenous thrombolysis and mechanical thrombectomy (MT) are guideline-recommended reperfusion therapies in large-vessel-occlusion ischemic stroke. However, for acute ischemic stroke of extracranial carotid artery origin (AIS-CA) there have been no specific trials, resulting in a data gap. MATERIAL AND METHODS We evaluated referral/treatment pathways, serial imaging, and neurologic 90-day outcomes in consecutive patients, presenting in a real-life series in 2 stroke centers over a period of 6 months, with AIS-CA eligible for emergency mechanical reperfusion (EMR) on top of thrombolysis as per guideline criteria. RESULTS Of 30 EMR-eligible patients (33.3% in-window for thrombolysis and thrombolysed, 73.3% male, age 39-87 years, median Alberta Stroke Program Early Computed Tomography Score (ASPECTS) 10, pre-stroke mRS 0-1 in all, tandem lesions 26.7%), 20 (66.7%) were EMR-referred (60% - endovascular, 6.7% - surgery referrals). Only 40% received EMR, nearly exclusively in stroke centers with carotid artery stenting (CAS) expertise (100% eligible patient acceptance rate, 100% treatment delivery involving CAS±MT with culprit lesion sequestration using micronet-covered stents). The emergency surgery rate was 0%. Baseline clinical and imaging characteristics did not differ between EMR-treated and EMR-untreated patients. Ninety-day neurologic status was profoundly better in EMR-treated patients: mRS 0-2 (91.7% vs 0%; P<0.001); mRS 3-5 (8.3% vs 88.9%; P<0.001), mRS 6 (0% vs 11.1%; P<0.001). CONCLUSIONS In a real-life AIS-CA setting, the referral rate of EMR-eligible patients for EMR was low, and the treatment rate was even lower. AIS-CA revascularization was delivered predominantly in stroke thrombectomy-capable cardioangiology centers, resulting in overwhelmingly superior patient outcome. Large vessel occlusion stroke referral and management pathways should involve centers with proximal-protected CAS expertise. AIS-CA, irrespective of any thrombolysis administration, is a hyperacute cerebral emergency and EMR-eligible patients should be immediately referred for mechanical reperfusion.

Safety and efficacy of low-cost alternative urokinase in acute ischemic stroke: A systematic review and meta-analysis

INTRODUCTION

Use of intravenous thrombolysis (IVT) for treatment of acute ischemic stroke (AIS) varies greatly between countries, ranging from 10% to 15% in high-income countries to less than 2% in low- and middle income countries (LMICs). This is because alteplase is expensive and has been cited as one of the most common barriers to IVT in LMICs. Urokinase (UK) is a thrombolytic agent which is almost 50 times cheaper with easier production and purification than alteplase. UK may become a cost-effective option for IVT in LMICs if it is found to be safe and effective. We conducted this study to assess the existing evidence on the safety and efficacy of UK vs alteplase for IVT in AIS.

METHODS

The study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-Analyses) guideline. Systematic literature search was done in PubMed, EMBASE, and Google Scholar for English literature published from 2010 to 2021.

RESULTS

A total of 4061 participants in the alteplase and 2062 participants in the UK group were included in the final statistical analysis. After IVT, a good functional outcome at last follow-up was found among 80.57 % of patients in the alteplase group compared to 73.79 % of patients in the UK group (OR: 1.11; 95 % CI: 0.95- 1.31; I2 = 0 %; P = 0.18). Symptomatic Intracerebral Hemorrhage (sICH) was found among 1.77 % of patients in the alteplase group compared to 2.83 % of patients in the UK group (OR: 0.84; 95 % CI: 0.56- 1.26; I2 = 0 %; P = 0.41). Similarly, mortality was found among 5.03 % of patients in the alteplase group compared to 5.42 % of patients in the UK group (OR: 0.87; 95 % CI: 0.66-1.14; I2 = 0 %; P = 0.30).

CONCLUSION

Our meta-analysis found that intravenous UK is not inferior to alteplase in terms of safety and efficacy and can be a viable alternative for IVT in AIS patients in LMICs.

Timing of symptomatic intracranial hemorrhage after endovascular stroke treatment

INTRODUCTION

Little is known about the timing of occurrence of symptomatic intracranial hemorrhage (sICH) after endovascular therapy (EVT) for acute ischemic stroke. A better understanding could optimize in-hospital surveillance time points and duration. The aim of this study was to delineate the probability of sICH over time and to identify factors associated with its timing.

PATIENTS AND METHODS

We retrospectively analyzed data from the Dutch MR CLEAN trial and MR CLEAN Registry. We included adult patients who underwent EVT for an anterior circulation large vessel occlusion within 6.5 h of stroke onset. In patients with sICH (defined as ICH causing an increase of ⩾4 points on the National Institutes of Health Stroke Scale [NIHSS]), univariable and multivariable linear regression analysis was used to identify factors associated with the timing of sICH. This was defined as the time between end of EVT and the time of first CT-scan on which ICH was seen as a proxy.

RESULTS

SICH occurred in 205 (6%) of 3391 included patients. Median time from end of EVT procedure to sICH detection on NCCT was 9.0 [IQR 2.9-22.5] hours, with a rapidly decreasing incidence after 24 h. None of the analyzed factors, including baseline NIHSS, intravenous alteplase treatment, and poor reperfusion at the end of the procedure were associated with the timing of sICH.

CONCLUSION

SICHs primarily occur in the first hours after EVT, and less frequently beyond 24 h. Guidelines that recommend to perform frequent neurological assessments for at least 24 h after intravenous alteplase treatment can be applied to ischemic stroke patients treated with EVT.

Intravenous thrombolysis plus mechanical thrombectomy versus mechanical thrombectomy alone for acute ischemic stroke: A systematic review and updated meta-analysis of clinical trials

BACKGROUND

Mechanical thrombectomy (MT) is the gold standard treatment for large vessel occlusion (LVO). A vital factor that might influence MT outcomes is the use of intravenous thrombolysis (IVT). A few clinical trials in this domain thus far have not yielded consistent outcomes. We conducted this meta-analysis to synthesize collective evidence in this regard.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines were followed, and we performed a comprehensive literature search of four databases (PubMed, Scopus, Web of Science, Cochrane CENTRAL). For outcomes constituting continuous data, the mean difference (MD) and its standard deviation (SD) were pooled. For outcomes constituting dichotomous data, the frequency of events and the total number of patients were pooled as the risk ratio (RR).

RESULTS

Seven clinical trials with a total of 2317 patients are included in this meta-analysis. Six trials are randomized, and one trial was nonrandomized. No significant differences were found between MT plus IVT and MT alone in successful recanalization (RR 1.04, 95% Confidence Interval (CI) [0.92 to 1.17], P = 0.53), 90-day functional independence (RR 1.03, 95% CI [0.90 to 1.19], P = 0.65), symptomatic intracranial hemorrhage (sICH) (RR 1.22, 95% CI [0.84 to 1.75], P = 0.30), or mortality (RR 0.94, 95% CI [0.76 to 1.18], P = 0.61).

CONCLUSION

The current evidence does not favor either MT plus IVT or MT alone for LVO except for the procedural time. More trials are needed in this regard, and certain factors should be considered when comparing the two approaches.

Predictors of Symptomatic Intracranial Hemorrhage after Endovascular Thrombectomy in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

INTRODUCTION

This meta-analysis assessed the predictors of symptomatic intracranial hemorrhage (sICH) after endovascular thrombectomy (EVT) for patients with acute ischemic stroke.

METHODS

PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science were searched for studies published from inception to February 16, 2021. We included studies that evaluated the predictors of sICH after EVT. The random-effect model or fixed-effect model was used to pool the estimates according to the heterogeneity.

RESULTS

A total of 25 cohort studies, involving 15,324 patients, were included in this meta-analysis. The total incidence of sICH was 6.72 percent. Age (MD = 2.57, 95% CI: 1.53-3.61; p < 0.00001), higher initial NIHSS score (MD = 1.71, 95% CI: 1.35-2.08, p < 0.00001), higher initial systolic blood pressure (MD = 7.40, 95% CI: 5.11-9.69, p < 0.00001), diabetes mellitus (OR = 1.36, 95% CI: 1.10-1.69, p = 0.005), poor collaterals (OR = 3.26, 95% CI: 2.35-4.51; p < 0.0001), internal carotid artery occlusion (OR = 1.55, 95% CI: 1.26-1.90; p < 0.0001), longer procedure time (MD = 18.92, 95% CI: 11.49-26.35; p < 0.0001), and passes of retriever >3 (OR = 3.39, 95% CI: 2.45-4.71; p < 0.0001) were predictors of sICH, while modified thrombolysis in cerebral infarction score ≥2b (OR = 0.61, 95% CI: 0.46-0.79; p = 0.0002) was associated with a decreased risk of sICH. There were no significant differences in the female gender, initial serum glucose, initial ASPECT score, atrial fibrillation, oral anticoagulants, antiplatelet therapy, intravenous thrombolysis, general anesthesia, neutrophil-to-lymphocyte ratio, and emergent stenting.

CONCLUSIONS

This study identified many predictors of sICH. Some of the results lack robust evidence given the limitations of the study. Therefore, larger cohort studies are needed to confirm these predictors.

No sex difference was found in the safety and efficacy of intravenous alteplase before endovascular therapy

Background and purpose

Prior studies on sex disparities were post-hoc analyses, had limited treatment modalities, and had controversial findings. Our study aimed to examine whether sex difference modifies the effect of intravenous alteplase before endovascular therapy.

Methods

We conducted a multicenter prospective cohort study of 850 eligible patients with acute ischemic stroke who underwent endovascular therapy. A propensity score was utilized as a covariate to achieve approximate randomization of alteplase pretreatment. The baseline characteristics of women and men were compared. Logistic regression with interaction terms, adjusted for potential confounders, was used to investigate the effect of sex on the prognosis of bridging therapy.

Results

In comparison to men, women were older [78.00 (70.00–84.00) vs. 67 (61.00–74.00), P &lt; 0.001], had more atrial fibrillation (61.4 vs. 35.2%, P &lt; 0.001), had a lower ASPECTS [10.00 (8.00–10.00) vs. 10 (9.00–10.00), P = 0.0047], and had a higher NIHSS score [17.00 (14.00–20.00) vs. 16 (13.00–19.00), P = 0.005]. Women tended to receive less bridging therapy (26.3 vs. 33%, P = 0.043) and more retrieval attempts [2.00 (1.00–2.00) vs. 1 (1.00–2.00), P = 0.026]. There was no sex difference in functional independence at 90 days after bridging therapy (OR 0.968, 95% CI 0.575–1.63), whereas men benefited more after EVT alone (OR 0.654, 95% CI 0.456–0.937). There were no sex-treatment interactions observed regardless of the location of the occlusion. There were no significant sex differences in all safety outcomes.

Conclusion

Our study could not confirm that sex modifies the treatment effect of intravenous alteplase before endovascular therapy. At the same time, we advocate for women to seek timely medical treatment.

[Neurothrombectomy 2022-Extension of indications and technical innovations]

For advanced territorial ischemia numerous retrospective and prospective studies have shown a positive effect of mechanical thrombectomy (MT) compared to best medicinal treatment alone. For patients with minor stroke (NIHSS < 6) there is currently a lack of evidence for MT. Appropriate study protocols must differentiate between patients with large vessel occlusion with disproportionately mild symptoms and more distal vascular occlusion and therefore correspondingly fewer clinical symptoms. The role of intravenous lysis treatment before MT as bridging lysis also currently retains its general recommendation, as large studies could not show a uniform noninferiority of MT alone. In addition, the use of intra-arterial lysis after successful MT offers a promising approach, which still needs to be evaluated. Novel aspiration catheters and stent-retrievers as well as competing thrombectomy techniques can be compared by the first pass effect, the successful recanalization with only one attempt at thrombectomy. Contact aspiration and stent-retriever thrombectomy under aspiration are equivalent and established thrombectomy procedures. For the latter, several detailed maneuver tactics are described for improvement of thrombectomy success. Also, in retrospective studies the combination with a balloon-guided catheter promises a further improvement of recanalization results. In the case of failure of supra-aortic vessel probing with inguinal access, radial access and direct carotid puncture are alternative access routes. Recent studies on ICA stenting with tandem occlusions showed a benefit of stents without an increased risk for symptomatic intracranial hemorrhage. The retrograde approach, to first treat the intracranial vessel occlusion and then the carotid stenosis, seems to be advantageous.

Effect of Admission Hyperglycemia on Safety and Efficacy of Intravenous Alteplase Before Thrombectomy in Ischemic Stroke: Post-hoc Analysis of the DIRECT-MT trial

Hyperglycemia is associated with decreased recanalization probability and increased risk of hemorrhagic complications for stroke patients treated with intravenous alteplase. However, whether hyperglycemia modifies alteplase treatment effect on clinical outcome in patients with large vessel occlusion stroke undergoing endovascular thrombectomy is uncertain. We conducted this study to determine a possible interaction effect between admission hyperglycemia and intravenous alteplase prior to thrombectomy in patients with large vessel occlusion stroke. In this post-hoc analysis of a randomized trial (DIRECT-MT) comparing intravenous alteplase before endovascular treatment vs. endovascular treatment only, 649 with available baseline glucose measurements were included. The treatment-by-admission hyperglycemia (defined as plasma glucose levels ≥ 7.8 mmol/L [140 mg/dL]) interaction was assessed using logistic regression models. As a result, among 649 patients included, 224 (34.5%) were hyperglycemic at admission. There was evidence of alteplase treatment effect modification by hyperglycemia (Pinteraction = 0.025). In patients without hyperglycemia, combination therapy was associated with better outcomes compared to mechanical thrombectomy alone (adjusted common odd ratio [acOR] 1.46, 95% CI [1.04-2.07]), but not in hyperglycemic patients (acOR 0.74, 95% CI [0.46-1.20]). Combination therapy led to an absolute increase of 6% excellent outcome (mRS 0-1) in non-hyperglycemic patients (aOR 1.71, 95% CI [1.05-2.79]), but resulted in a 12.3% absolute decrease (aOR 0.42 [95% CI, 0.19-0.95] in hyperglycemic patients (Pinteraction = 0.003). In conclusion, for large vessel occlusion patients directly presenting to a thrombectomy-capable hospital, hyperglycemia modified combination treatment effect on clinical outcome. Combination therapy was beneficial in patients without hyperglycemia, while thrombectomy alone may be preferred in hyperglycemic patients. Further studies are needed to confirm this result.Trial Registration Information: clinicaltrials.gov Identifier: NCT03469206.

Endovascular thrombectomy or bridging therapy in minor ischemic stroke with large vessel occlusion

BACKGROUND

Whether direct endovascular thrombectomy (EVT) is non-inferior to bridging therapy (intravenous thrombolysis [IVT] followed by EVT) in minor acute ischemic stroke due to large vessel occlusions (AIS-LVO) is not clear. Therefore, this study aimed to assess whether direct EVT is non-inferior to bridging therapy in minor AIS-LVO.

METHODS

903 patients with acute ischemic stroke due to large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) score <6 receiving EVT treatment were enrolled at Bigdata Observatory Platform for Stroke of China in China from January 1, 2019, to December 31, 2020, with final follow-up on March 31, 2021. The primary efficacy endpoint was a favorable outcome defined as a modified Rankin Scale score of 0 to 2 at three months. In addition, there were three prespecified secondary efficacy endpoints, including symptomatic intracerebral hemorrhage (ICH), in-hospital mortality, and mortality by month 3.

RESULTS

A total of 662 patients treated with direct EVT (age 65.9 ± 10.5 years, 71.5 % male, NIHSS score 2.4 [standard deviation {SD}. 1.8]) were compared to 241 bridging-treated patients (age 65.7 ± 10.8, 75.9 % female, NIHSS score 2.5 [1.8]). The rate of symptomatic ICH in the EVT group was lower than in the bridging group (4.2 % vs. 8.3 %; P = 0.02). The in-hospital mortality was not different between the two groups (EVT vs. bridging group: adjusted hazard ratio {HR}, 0.9 [95 % confidence interval {CI}, 0.5 to 1.9]; P = 0.93). There was no significant difference in 3-month poor functional outcome rate (EVT vs. bridging group: 17.1 % vs. 16.2 % [absolute difference, 0.9 % {95 % CI, -0.8 % to 2.4 %}, P = 0.75; adjusted hazard ratio {HR}, 1.0 {95 % CI, 0.6 to 1.7}, P = 0.83]) and mortality rate (13.0 % vs. 11.2 % [absolute difference, 1.5 % {95 % CI, -3.9 % to 6.8 %}, P = 0.47; adjusted HR, 1.1 {95 % CI, 0.8 to 1.9}, P = 0.55]) between those two groups.

CONCLUSION

Among patients with minor AIS-LVO, direct EVT, compared with bridging therapy, met the prespecified statistical threshold for noninferiority for the 3-month prognosis.

Endovascular thrombectomy and intravenous alteplase in patients with acute ischemic stroke due to large vessel occlusion: A clinical practice guideline

AIM

Whether or not use of intravenous alteplase in combination with endovascular thrombectomy (EVT) improves outcomes versus EVT alone, for acute stroke patients with large vessel occlusion presenting directly to a comprehensive stroke center, is uncertain.

METHODS

Six randomized trials exploring this issue were published, and we synthesized this evidence to inform a rapid guideline based on the Guidelines International Network principles and guided by the GRADE approach.

RESULTS

We enlisted an international panel that included 4 patient partners and 1 caregiver, individuals from 6 countries. The panel considered low certainty evidence that EVT alone, relative to EVT with intravenous alteplase, possibly results in a small decrease in the proportion of patients that achieve functional independence and possibly a small increase in mortality. Both effect estimates were downgraded twice due to very serious imprecision. The panel also considered moderate certainty evidence that EVT alone probably decreases symptomatic intracranial hemorrhage, versus EVT with alteplase, and combination therapy was more costly than EVT alone. As a result of the low certainty for improved recovery without impairment and mortality for combination therapy versus EVT alone, and moderate certainty for increased harm with combination therapy, the panel made a weak recommendation in favor of EVT alone for stroke patients eligible for both treatments, and initially presenting directly to a comprehensive stroke center that provides both treatments.

CONCLUSIONS

Consistent with this weak recommendation, optimal patient management will likely often include co-treatment with intravenous alteplase, depending on local circumstances and patient presentation.

Effect of Tetrahedral Framework Nucleic Acids on Neurological Recovery via Ameliorating Apoptosis and Regulating the Activation and Polarization of Astrocytes in Ischemic Stroke

Astrocytes, as the most plentiful subtypes of glial cells, play an essential biphasic function in ischemic stroke (IS). However, although having beneficial effects on stroke via promoting nerve restoration and limiting lesion extension, astrocytes can unavoidably cause exacerbated brain damage due to their participation in the inflammatory response. Therefore, seeking an effective and safe drug/strategy for protecting and regulating astrocytes in stroke is urgent. Here, we employ tetrahedral framework nucleic acid (tFNA) nanomaterials for astrocytes in stroke, considering their excellent biological properties and outstanding biosafety. In vitro, tFNA can inhibit calcium overload and ROS regeneration triggered by oxygen-glucose deprivation/reoxygenation (OGD/R), which provides a protective effect against astrocytic apoptosis. Furthermore, morphological changes such as hyperplasia and hypertrophy of reactive astrocytes are restrained, and the astrocytic polarization from the proinflammatory A1 phenotype to the neuroprotective A2 phenotype is facilitated by tFNA, which further alleviates cerebral infarct volume and facilitates the recovery of neurological function in transient middle cerebral artery occlusion (tMCAo) rat models. Moreover, the TLRs/NF-κB signaling pathway is downregulated by tFNA, which may be the potential mechanism of tFNA for protecting astrocytes in stroke. Collectively, we demonstrate that tFNA can effectively mediate astrocytic apoptosis, activation, and polarization to alleviate brain injury, which represents a potential intervention strategy for IS.

Need for a Paradigm Shift in the Treatment of Ischemic Stroke: The Blood-Brain Barrier

Blood-brain barrier (BBB) integrity is essential to maintaining brain health. Aging-related alterations could lead to chronic progressive leakiness of the BBB, which is directly correlated with cerebrovascular diseases. Indeed, the BBB breakdown during acute ischemic stroke is critical. It remains unclear, however, whether BBB dysfunction is one of the first events that leads to brain disease or a down-stream consequence. This review will focus on the BBB dysfunction associated with cerebrovascular disease. An added difficulty is its association with the deleterious or reparative effect, which depends on the stroke phase. We will first outline the BBB structure and function. Then, we will focus on the spatiotemporal chronic, slow, and progressive BBB alteration related to ischemic stroke. Finally, we will propose a new perspective on preventive therapeutic strategies associated with brain aging based on targeting specific components of the BBB. Understanding BBB age-evolutions will be beneficial for new drug development and the identification of the best performance window times. This could have a direct impact on clinical translation and personalised medicine.

In Vitro Blood Clot Formation and Dissolution for Testing New Stroke-Treatment Devices

Strokes are among the leading causes of death worldwide. Ischemic stroke, due to plaque or other buildup blocking blood flow to the brain, is the most common type. Although ischemic stroke is treatable, current methods have severe shortcomings with high mortality rates. Clot retrieval devices, for example, can result in physically damaged vessels and death. This study aims to create blood clots that are representative of those found in vivo and demonstrate a new method of removing them. Static blood clots were formed using a 9:1 ratio of whole sheep blood and 2.45% calcium chloride solution. This mixture was heated in a water bath at 37 °C for approximately one hour until solidified. Following clot solidification, human plasmin was introduced by various methods, including soaking, injection, and membrane perfusion, and the resulting dissolution percentages were determined. Different clot types, representative of the wide range found physiologically, were also manufactured and their dissolution characteristics evaluated. A method to reproducibly create blood clots, characteristic of those found in vivo, is essential for the production of stroke retrieval devices that can efficiently and effectively remove clots from patients with low mortality rates and little/no damage to the surrounding vessels.

Bridging intravenous thrombolysis in patients with atrial fibrillation

Background and purpose

40% of acute ischemic stroke patients treated by mechanical thrombectomy (MT) have a clinical history of atrial fibrillation (AF). The safety of bridging intravenous thrombolysis (IVT) (MT + IVT) is currently being discussed. We aimed to analyze the interaction between oral anticoagulation (OAC) status or AF with bridging IVT, regarding the occurrence of symptomatic intracranial hemorrhage (sICH) and functional outcome.

Materials and Methods

Multicentric observational cohort study (BEYOND-SWIFT registry) of consecutive patients undergoing MT between 2010 and 2018 (n = 2,941). Multinomial regression models were adjusted for prespecified baseline and plausible pathophysiological covariates identified on a univariate analysis to assess the association of AF and OAC status with sICH and good outcomes (90-day modified Rankin Scale score 0–2).

Results

In the total cohort (median age 74, 50.6% women), 1,347 (45.8%) patients had AF. Higher admission National Institutes of Health Stroke Scale (NIHSS) score (aOR 1.04 [95% 1.02–1.06], per point of increase) and prior medication with Vitamin K antagonists (VKA) (aOR 2.19 [95% 1.27–3.66]) were associated with sICH. Neither AF itself (aOR 0.71 [95% 0.41–1.24]) nor bridging IVT (aOR 1.08 [0.67–1.75]) were significantly associated with increased sICH. Receiving bridging IVT (aOR 1.61 [95% 1.24–2.11]) was associated with good 90-day outcome, with no interaction between AF and IVT (p = 0.92).

Conclusion

Bridging IVT appears to be a reasonable clinical option in selected patients with AF. Given the increased sICH risk in patients with VKA, subgroup analysis of the randomized controlled trials should analyze whether patients with VKA might benefit from withholding bridging IVT.

Registration

clinicaltrials.gov; Unique identifier: NCT03496064.

Alteplase or tenecteplase for thrombolysis in ischemic stroke: An illustrated review

Intravenous thrombolysis is a standard of care treatment for patients with acute ischemic stroke. Tissue plasminogen activator (tPA) has been the main thrombolytic agent used since the publication of the seminal National Institutes of Neurological Disorders and Stroke trial in 1995. There is now mounting evidence to support the routine use of Tenecteplase (TNK) to treat acute ischemic stroke. TNK is a genetically modified tPA with higher fibrin specificity, longer half‐life, and reduced systemic coagulopathy. In this illustrated review, we compare the indications, doses, mechanisms of action, efficacy and safety of TNK and tPA. We provide an overview of published clinical trials studying TNK in acute ischemic stroke, including dose‐escalation studies and head‐to‐head comparisons with tPA. Finally, we summarize current acute stroke guideline recommendations and suggest treatment algorithms to manage the two main complications of intravenous thrombolysis: symptomatic intracerebral hemorrhage and angioedema.

Predictors of symptomatic intracranial hemorrhage after endovascular treatment for acute large vessel occlusion: data from ANGEL-ACT registry

Symptomatic intracranial hemorrhage (SICH) is a catastrophic complication of endovascular treatment (EVT) for large vessel occlusion (LVO). We aimed to investigate the incidence and predictors of SICH after EVT. Patients were selected from the ANGEL-ACT registry. We diagnosed SICH according to the Heidelberg Bleeding Classification. Logistic regression analyses were performed to determine the independent predictors of SICH. Of the 1283 patients, SICH was observed in 116 patients (9.0%). On multivariable analysis, admission National Institutes of Health Stroke Scale (NIHSS) > 12 (odds ratio [OR] = 1.86, 95% confidence interval [CI]: 1.11-3.11, P = 0.018), admission Alberta Stroke Program Early CT Score (ASPECTS) < 6 (OR = 2.98, 95%CI: 1.68-5.29, P < 0.001), general anesthesia (OR = 1.81, 95%CI: 1.20-2.71, P = 0.004), prior intravenous thrombolysis (OR = 1.58, 95%CI: 1.04-2.40, P = 0.031), number of mechanical thrombectomy passes > 2 (OR = 1.68, 95%CI: 1.10-2.57, P = 0.016), and procedure duration > 96 min (OR = 1.82, 95%CI: 1.20-2.77, P = 0.005) were associated with high risk of SICH, whereas SICH was negatively associated with underlying intracranial atherosclerotic disease (OR = 0.45, 95%CI: 0.26-0.79, P = 0.021). The incidence of SICH after EVT for anterior LVO was 9.0% in ANGEL-ACT registry. Our study identified some predictors, which may assist doctors in identifying LVO patients with a high risk of SICH and making the optimal peri-procedural management strategies for such patients.

CT Hyperdense Artery Sign and the Effect of Alteplase in Endovascular Thrombectomy after Acute Stroke

Background Recent evidence suggests that presence of an intracranial arterial thrombus with a hyperdense artery sign (HAS) at noncontrast CT (NCCT) is associated with better response to intravenous alteplase. Patients with HAS may benefit more from combined intravenous alteplase and endovascular treatment (EVT). Purpose To investigate whether HAS at NCCT modifies the treatment effect of adding intravenous alteplase on clinical outcome in patients with acute large-vessel occlusion undergoing EVT. Materials and Methods This study is a secondary analysis of a prospective randomized trial (Direct Intra-arterial thrombectomy in order to Revascularize AIS patients with large-vessel occlusion Efficiently in Chinese Tertiary hospitals: A Multicenter randomized clinical Trial [DIRECT-MT]), which compared adding alteplase to EVT versus EVT alone in participants with acute large-vessel occlusion between February 2018 and July 2019. Participants with catheter angiograms and adequate NCCT for HAS evaluation were included. HAS was determined visually by two independent investigators at baseline NCCT. Treatment effect of intravenous alteplase administration according to presence of HAS on the primary clinical outcome (modified Rankin Scale [mRS] score at 90 days) and secondary and safety outcomes were assessed using adjusted multivariable regression models. Results Among 633 included participants (356 men [56%]; median age, 69 years), HAS was observed in 283 participants (45%): 142 of 313 participants (45%) in the EVT-only group and 141 of 320 participants (44%) in the group with added intravenous alteplase. Treatment-by-HAS interaction was observed for the primary outcome (P < .001), whereby a shift in favor of better outcomes with added intravenous alteplase occurred in participants with HAS (adjusted odds ratio [OR]: 1.82; 95% CI: 1.18, 2.79), while an adverse effect was seen in participants without HAS (adjusted OR: 0.62; 95% CI: 0.42, 0.91). This also held true for three secondary outcomes (excellent outcome [mRS score of 0-1 at 90 days], P = .005; good outcome [mRS score of 0-2 at 90 days], P = .008; final successful reperfusion, P = .04) in the adjusted models. Conclusion After acute ischemic stroke, presence of hyperdense artery sign (HAS) at baseline noncontrast CT indicated better outcomes when alteplase was added to endovascular treatment, but adding alteplase to endovascular treatment resulted in worse outcomes in participants without HAS. Clinical trial registration no. NCT03469206 © RSNA, 2022 Online supplemental material is available for this article.

Clinical Importance of the Persistent Primitive Trigeminal Artery in Vascular Lesions and Its Role in Endovascular Treatment

The persistent primitive trigeminal artery (PPTA) extends from the internal carotid artery to the basilar artery between the origins of the anterior inferior cerebellar artery and superior cerebellar artery. PPTAs have complex anatomical characteristics. Salas and Saltzman classifications are most often used in PPTAs. The PPTA can play many roles in vascular lesions, including intracranial aneurysms, brain arteriovenous malformations, trigeminal artery-cavernous fistulas, Moyamoya disease, and large vessel occlusion. For these lesions, surgical treatment is difficult due to the deep location and complex anatomy of the PPTA, but endovascular treatment (EVT) has emerged as a good alternative. Currently, a complete review of the clinical importance of the PPTA in terms of its role in the development and EVT of vascular lesions is lacking. Therefore, we conducted a PubMed search, performed a review of the relevant extracted literature and cataloged our experience with PPTAs. By review, we found that a thorough understanding of the anatomical and angiographic features of this PPTA is of utmost importance when making therapeutic decisions for any of these pathological conditions.

Thrombectomy alone versus intravenous alteplase plus thrombectomy in patients with stroke: an open-label, blinded-outcome, randomised non-inferiority trial

BACKGROUND

Whether thrombectomy alone is equally as effective as intravenous alteplase plus thrombectomy remains controversial. We aimed to determine whether thrombectomy alone would be non-inferior to intravenous alteplase plus thrombectomy in patients presenting with acute ischaemic stroke.

METHODS

In this multicentre, randomised, open-label, blinded-outcome trial in Europe and Canada, we recruited patients with stroke due to large vessel occlusion confirmed with CT or magnetic resonance angiography admitted to endovascular centres. Patients were randomly assigned (1:1) via a centralised web server using a deterministic minimisation method to receive stent-retriever thrombectomy alone or intravenous alteplase plus stent-retriever thrombectomy. In both groups, thrombectomy was initiated as fast as possible with any commercially available Solitaire stent-retriever revascularisation device (Medtronic, Irvine, CA, USA). In the combined treatment group, intravenous alteplase (0·9 mg/kg bodyweight, maximum dose 90 mg per patient) was administered as early as possible after randomisation for 60 min with 10% of the calculated dose given as an initial bolus. Personnel assessing the primary outcome were masked to group allocation; patients and treating physicians were not. The primary binary outcome was a score of 2 or less on the modified Rankin scale at 90 days. We assessed the non-inferiority of thrombectomy alone versus intravenous alteplase plus thrombectomy in all randomly assigned and consenting patients using the one-sided lower 95% confidence limit of the Mantel-Haenszel risk difference, with a prespecified non-inferiority margin of 12%. The main safety endpoint was symptomatic intracranial haemorrhage assessed in all randomly assigned and consenting participants. This trial is registered with ClinicalTrials.gov, NCT03192332, and is closed to new participants.

FINDINGS

Between Nov 29, 2017, and May 7, 2021, 5215 patients were screened and 423 were randomly assigned, of whom 408 (201 thrombectomy alone, 207 intravenous alteplase plus thrombectomy) were included in the primary efficacy analysis. A modified Rankin scale score of 0-2 at 90 days was reached by 114 (57%) of 201 patients assigned to thrombectomy alone and 135 (65%) of 207 patients assigned to intravenous alteplase plus thrombectomy (adjusted risk difference -7·3%, 95% CI -16·6 to 2·1, lower limit of one-sided 95% CI -15·1%, crossing the non-inferiority margin of -12%). Symptomatic intracranial haemorrhage occurred in five (2%) of 201 patients undergoing thrombectomy alone and seven (3%) of 202 patients receiving intravenous alteplase plus thrombectomy (risk difference -1·0%, 95% CI -4·8 to 2·7). Successful reperfusion was less common in patients assigned to thrombectomy alone (182 [91%] of 201 vs 199 [96%] of 207, risk difference -5·1%, 95% CI -10·2 to 0·0, p=0·047).

INTERPRETATION

Thrombectomy alone was not shown to be non-inferior to intravenous alteplase plus thrombectomy and resulted in decreased reperfusion rates. These results do not support omitting intravenous alteplase before thrombectomy in eligible patients.

FUNDING

Medtronic and University Hospital Bern.

Endovascular thrombectomy versus standard bridging thrombolytic with endovascular thrombectomy within 4·5 h of stroke onset: an open-label, blinded-endpoint, randomised non-inferiority trial

BACKGROUND

The benefit of combined treatment with intravenous thrombolysis before endovascular thrombectomy in patients with acute ischaemic stroke caused by large vessel occlusion remains unclear. We hypothesised that the clinical outcomes of patients with stroke with large vessel occlusion treated with direct endovascular thrombectomy within 4·5 h would be non-inferior compared with the outcomes of those treated with standard bridging therapy (intravenous thrombolysis before endovascular thrombectomy).

METHODS

DIRECT-SAFE was an international, multicentre, prospective, randomised, open-label, blinded-endpoint trial. Adult patients with stroke and large vessel occlusion in the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or basilar artery, confirmed by non-contrast CT and vascular imaging, and who presented within 4·5 h of stroke onset were recruited from 25 acute-care hospitals in Australia, New Zealand, China, and Vietnam. Eligible patients were randomly assigned (1:1) via a web-based, computer-generated randomisation procedure stratified by site of baseline arterial occlusion and by geographic region to direct endovascular thrombectomy or bridging therapy. Patients assigned to bridging therapy received intravenous thrombolytic (alteplase or tenecteplase) as per standard care at each site; endovascular thrombectomy was also per standard of care, using the Trevo device (Stryker Neurovascular, Fremont, CA, USA) as first-line intervention. Personnel assessing outcomes were masked to group allocation; patients and treating physicians were not. The primary efficacy endpoint was functional independence defined as modified Rankin Scale score 0-2 or return to baseline at 90 days, with a non-inferiority margin of -0·1, analysed by intention to treat (including all randomly assigned and consenting patients) and per protocol. The intention-to-treat population was included in the safety analyses. The trial is registered with ClinicalTrials.gov, NCT03494920, and is closed to new participants.

FINDINGS

Between June 2, 2018, and July 8, 2021, 295 patients were randomly assigned to direct endovascular thrombectomy (n=148) or bridging therapy (n=147). Functional independence occurred in 80 (55%) of 146 patients in the direct thrombectomy group and 89 (61%) of 147 patients in the bridging therapy group (intention-to-treat risk difference -0·051, two-sided 95% CI -0·160 to 0·059; per-protocol risk difference -0·062, two-sided 95% CI -0·173 to 0·049). Safety outcomes were similar between groups, with symptomatic intracerebral haemorrhage occurring in two (1%) of 146 patients in the direct group and one (1%) of 147 patients in the bridging group (adjusted odds ratio 1·70, 95% CI 0·22-13·04) and death in 22 (15%) of 146 patients in the direct group and 24 (16%) of 147 patients in the bridging group (adjusted odds ratio 0·92, 95% CI 0·46-1·84).

INTERPRETATION

We did not show non-inferiority of direct endovascular thrombectomy compared with bridging therapy. The additional information from our study should inform guidelines to recommend bridging therapy as standard treatment.

FUNDING

Australian National Health and Medical Research Council and Stryker USA.

Acute Neurointervention for Ischemic Stroke

Acute ischemic stroke (AIS) is one of the major causes of death worldwide and a leading cause of disability. Until recently treatment of AIS was supportive, and in a minority of patients intravenous thrombolysis was available but with marginal clinical benefit. With the advent of stent retrievers, distal aspiration catheters as well as improved patient selection neurologic outcomes have greatly improved. However, the care of patients with AIS is still challenging and requires the early recognition of stroke symptoms, extensive diagnostic testing, early intervention, and advanced nursing and critical care.

A Presurgical Unfavorable Prediction Scale of Endovascular Treatment for Acute Ischemic Stroke

Objective

To develop a prognostic prediction model of endovascular treatment (EVT) for acute ischemic stroke (AIS) induced by large-vessel occlusion (LVO), this study applied machine learning classification model light gradient boosting machine (LightGBM) to construct a unique prediction model.

Methods

A total of 973 patients were enrolled, primary outcome was assessed with modified Rankin scale (mRS) at 90 days, and favorable outcome was defined using mRS 0–2 scores. Besides, LightGBM algorithm and logistic regression (LR) were used to construct a prediction model. Then, a prediction scale was further established and verified by both internal data and other external data.

Results

A total of 20 presurgical variables were analyzed using LR and LightGBM. The results of LightGBM algorithm indicated that the accuracy and precision of the prediction model were 73.77 and 73.16%, respectively. The area under the curve (AUC) was 0.824. Furthermore, the top 5 variables suggesting unfavorable outcomes were namely admitting blood glucose levels, age, onset to EVT time, onset to hospital time, and National Institutes of Health Stroke Scale (NIHSS) scores (importance = 130.9, 102.6, 96.5, 89.5 and 84.4, respectively). According to AUC, we established the key cutoff points and constructed prediction scale based on their respective weightings. Then, the established prediction scale was verified in raw and external data and the sensitivity was 80.4 and 83.5%, respectively. Finally, scores &gt;3 demonstrated better accuracy in predicting unfavorable outcomes.

Conclusion

Presurgical prediction scale is feasible and accurate in identifying unfavorable outcomes of AIS after EVT.

Predictive Factors for Clinical Outcome After Direct Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion Within 4.5 h

Background

Recent trials including DIRECT-MT, DEVT, and SKIP have found that direct mechanical thrombectomy (MT) is equally effective as the combination of MT and intravenous thrombolysis. However, the results of the other trials, namely MR-CLEAN NO-IV and the SWIFT-DIRECT trial have failed to confirm the non-inferiority of direct MT vs. the combination therapy.

Aim

We aimed to identify prognostic factors of direct MT for anterior circulation large vessel occlusion within 4.5 h.

Materials and Methods

Data from January 2018 to January 2022 were retrospectively collected and analyzed. Adult patients with confirmed anterior circulation large vessel occlusion within 4.5 h of onset with baseline NIHSS of ≥6 and baseline ASPECTS of ≥6 treated using direct MT within 6 h were recruited.

Results

A total of 140 patients were enrolled in the study with a median age of 65.5 years [interquartile range (IQR), 59–76.5], median baseline NIHSS of 13.5 (IQR, 11–16), and median baseline ASPECTS of 8 (IQR, 7–8). Direct MT was feasible in all patients (100%). Successful reperfusion (mTICI 2b-3) was achieved in 124/140 patients (88.6%) with a low rate of complications (8/140, 5.7%). Any type of intracranial hemorrhage (ICH) and symptomatic ICH occurred in 44/140 (31.4%) and 5/140 (3.6%), respectively. Overall, a good outcome (mRS 0–2) was achieved in 93/140 (66.4%), and the mortality rate was 9.3% (13/140 patients). Using multivariate analysis, lower age [odds ratio (OR), 0.96; 95% CI, 0.92–1.00; P = 0.05], low baseline NIHSS (OR, 0.82; 95% CI, 0.74–0.92; P = 0.00), and absence of ICH (OR, 0.29; 95% CI, 0.10–0.81; P = 0.02) were independently associated with favorable outcome. Independent predictors of mortality were baseline NIHSS (OR, 1.21; 95% CI, 1.01–1.46; P = 0.04), successful reperfusion (OR, 0.02; 95% CI, 0.00–0.58; P = 0.02), and ICH (OR, 0.12; 95% CI, 0.02–0.75; P = 0.02). Further analysis showed that the median mRS at 90 days was significantly better in the MCA occlusion group compared to the ICA plus M1 occlusion group [1 (IQR 0–3) vs. 2 (IQR 1–4); P = 0.05].

Conclusions

Our findings suggest that direct thrombectomy may be an adequate clinical option for younger patients (≤70) experiencing proximal middle artery occlusion within 4.5 h and who have low baseline NIHSS (≤14).

Safety and Efficacy of Intravenous Alteplase before Endovascular Thrombectomy: A Pooled Analysis with Focus on the Elderly

Current guidelines advocate intravenous thrombolysis (IVT) prior to endovascular thrombectomy (EVT) for all patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). We evaluated outcomes with and without IVT pretreatment. Our institutional protocols allow AIS patients presenting early (<4 h from onset or last seen normal) who have an Alberta Stroke Program Early CT Score (ASPECTS) ≥6 to undergo EVT without IVT pretreatment if the endovascular team is in the hospital (direct EVT). Rates of recanalization and hemorrhagic transformation (HT) and neurological outcomes were retrospectively compared in consecutive patients undergoing IVT+EVT vs. direct EVT with subanalyses in those ≥80 years and ≥85 years. In the overall cohort (IVT+EVT = 147, direct EVT = 162), and in subsets of patients ≥80 years (IVT+EVT = 51, direct EVT = 50) and ≥85 years (IVT+EVT = 19, direct EVT = 32), the IVT+EVT cohort and the direct EVT group had similar baseline characteristics, underwent EVT after a comparable interval from symptom onset, and reached similar rates of target vessel recanalization. No differences were observed in the HT frequency, or in disability at discharge or after 90 days. Patients receiving direct EVT underwent more stenting of the carotid artery due to stenosis during the EVT procedure (22% vs. 6%, p = 0.001). Direct EVT and IVT+EVT had comparable neurological outcomes in the overall cohort and in the subgroups of patients ≥80 and ≥85 years, suggesting that direct EVT should be considered in patients with an elevated risk for HT.

Intravenous tPA (Tissue-Type Plasminogen Activator) Correlates With Favorable Venous Outflow Profiles in Acute Ischemic Stroke

BACKGROUND

Intravenous tPA (tissue-type plasminogen activator) is often administered before endovascular thrombectomy (EVT). Recent studies have questioned whether tPA is necessary given the high rates of arterial recanalization achieved by EVT, but whether tPA impacts venous outflow (VO) is unknown. We investigated whether tPA improves VO profiles on baseline computed tomography (CT) angiography (CTA) images before EVT.

METHODS

Retrospective multicenter cohort study of patients with acute ischemic stroke due to large vessel occlusion undergoing EVT triage. Included patients underwent CT, CTA, and CT perfusion before EVT. VO profiles were determined by opacification of the vein of Labbé, sphenoparietal sinus, and superficial middle cerebral vein on CTA as 0, not visible; 1, moderate opacification; and 2, full. Pial arterial collaterals were graded on CTA, and tissue-level collaterals were assessed on CT perfusion using the hypoperfusion intensity ratio. Clinical and demographic data were determined from the electronic medical record. Using multivariable regression analysis, we determined the correlation between tPA administration and favorable VO profiles.

RESULTS

Seven hundred seventeen patients met inclusion criteria. Three hundred sixty-five patients received tPA (tPA+), while 352 patients were not treated with tPA (tPA-). Fewer tPA+ patients had atrial fibrillation (n=128 [35%] versus n=156 [44%]; P=0.012) and anticoagulants/antiplatelet treatment before acute ischemic stroke due to large vessel occlusion onset (n=130 [36%] versus n=178 [52%]; P<0.001) compared with tPA- patients. One hundred eighty-five patients (51%) in the tPA+ and 100 patients (28%) in the tPA- group exhibited favorable VO (P<0.001). Multivariable regression analysis showed that tPA administration was a strong independent predictor of favorable VO profiles (OR, 2.6 [95% CI, 1.7-4.0]; P<0.001) after control for favorable pial arterial CTA collaterals, favorable tissue-level collaterals on CT perfusion, age, presentation National Institutes of Health Stroke Scale, antiplatelet/anticoagulant treatment, history of atrial fibrillation and time from symptom onset to imaging.

CONCLUSIONS

In patients with acute ischemic stroke due to large vessel occlusion undergoing thrombectomy triage, tPA administration was strongly associated with the presence of favorable VO profiles.

Clinical Value of Combined Detection of UA and MMP-9 in Evaluating Bleeding Transformation and Prognosis After Thrombolysis in Acute Cerebral Infarction

This paper presents an in-depth study and analysis of the assessment of hemorrhagic transformation and prognostic outcome after thrombolysis in acute cerebral infarction using a combined test and evaluates its clinical value. The ischemic tissue hemodynamic changes were compared and analyzed by the combined application of magnetic resonance conventional examination. Single-factor and multi-factor Logistic regression analysis was applied to the model group samples to determine the independent influencing factors of hemorrhage and to construct a risk prediction model. The Hosmer-Lemeshow chi-square test was used to test the fit of the model, and the area under the ROC curve was used to test the discriminatory ability of the model. The area under the ROC curve was used to test the discriminatory ability of the model. The main purpose of this study was to investigate the clinical diagnostic value of the combined D-D and Hcy and test for the early detection of patients with acute cerebral infarction disease. There was no significant correlation between single PWI-ASPECTS and clinical prognostic MRS score, which may be related to the site and volume of initial diffusion restriction; the percentage of the mismatched area between DWI-PWI and clinical prognostic mRS score was significantly correlated, which helps clinicians to assess the therapeutic effect of non-thrombolytic therapy and provide an important basis for clinical selection of appropriate interventions in the subacute phase of stroke. The sensitivity of D-D, Hcy, and cTnI in the acute cerebral infarction group was 59.4%, 79.6%, and 49.5%, and the specificity was 73.5%, 70.5%, and 91.1%, respectively, with the area under the curve of 0.606, 0.729, and 0.521. The sensitivity, specificity, and area under the curve of the combined assay were higher than those of the single assay. The detection level of high-risk group was the highest, followed by the low-risk group. Pearson correlation analysis suggests that there is a significant correlation between serum UA and MM-9 level and grace score.

Endovascular thrombectomy with or without intravenous alteplase for acute ischemic stroke due to large vessel occlusion: a systematic review and meta-analysis of randomized trials

BACKGROUND

Among patients who had an ischaemic stroke presenting directly to a stroke centre where endovascular thrombectomy (EVT) is immediately available, there is uncertainty regarding the role of intravenous thrombolysis agents before or concurrently with EVT. To support a rapid guideline, we conducted a systematic review and meta-analysis to examine the impact of EVT alone versus EVT with intravenous alteplase in patients who had an acute ischaemic stroke due to large vessel occlusion.

METHODS

In November 2021, we searched MEDLINE, Embase, PubMed, Cochrane, Web of Science, clincialtrials.gov and the ISRCTN registry for randomised controlled trials (RCTs) comparing EVT alone versus EVT with alteplase for acute ischaemic stroke. We conducted meta-analyses using fixed effects models and assessed the certainty of evidence using the GRADE approach.

RESULTS

In total 6 RCTs including 2334 participants were eligible. Low certainty evidence suggests that, compared with EVT and alteplase, there is possibly a small decrease in the proportion of patients independent with EVT alone (risk ratio (RR) 0.97, 95% CI 0.89 to 1.05; risk difference (RD) -1.5%; 95% CI -5.4% to 2.5%), and possibly a small increase in mortality with EVT alone (RR 1.07, 95% CI 0.88 to 1.29; RD 1.2%, 95% CI -2.0% to 4.9%) . Moderate certainty evidence suggests that there is probably a small decrease in symptomatic intracranial haemorrhage (sICH) with EVT alone (RR 0.75, 95% CI 0.52 to 1.07; RD -1.0%; 95%CI -1.8% to 0.27%).

CONCLUSIONS

Low certainty evidence suggests that there is possibly a small decrease in the proportion of patients that achieve functional independence and a small increase in mortality with EVT alone. Moderate certainty evidence suggests that there is probably a small decrease in sICH with EVT alone. The accompanying guideline provides contextualised guidance based on this body of evidence.

PROSPERO REGISTRATION NUMBER

CRD42021249873.

Outcomes After Endovascular Thrombectomy With or Without Alteplase in Routine Clinical Practice

Importance

The effectiveness and safety of intravenous alteplase given before or concurrently with endovascular thrombectomy (EVT) is uncertain. Randomized clinical trials suggest there is little difference in outcomes but with only modest precision and insufficient power to analyze uncommon outcomes including symptomatic intracranial hemorrhage (sICH).

Objective

To determine whether 8 prespecified outcomes are different in patients with acute ischemic stroke treated in routine clinical practice with EVT with alteplase compared with patients treated with EVT alone without alteplase. It was hypothesized that alteplase would be associated with higher risk of sICH.

Design, Setting, and Participants

This was an observational cohort study conducted from February 1, 2019, to June 30, 2020, that included adult patients with acute ischemic stroke treated with EVT within 6 hours of time last known well, after excluding patients without information on discharge destination and patients with in-hospital stroke. Participants were recruited from Get With The Guidelines-Stroke, a large nationwide registry of patients with acute ischemic stroke from 555 hospitals in the US.

Exposures

Intravenous alteplase or no alteplase.

Main Outcomes and Measures

Prespecified outcomes were discharge destination, independent ambulation at discharge, modified Rankin score at discharge, discharge mortality, cerebral reperfusion according to modified Thrombolysis in Cerebral Infarction grade, and sICH.

Results

There were 15 832 patients treated with EVT (median [IQR] age, 72.0 [61.0-82.0] years; 7932 women [50.1%]); 10 548 (66.7%) received alteplase and 5284 (33.4%) did not. Patients treated with alteplase were younger, arrived via Emergency Medical Services sooner, were less likely to have certain comorbidities, including atrial fibrillation, hypertension, and diabetes, but had similar National Institutes of Health Stroke Severity (NIHSS) scores. Compared with patients who did not receive alteplase treatment, patients treated with alteplase were less likely to die (11.1% [1173 of 10 548 patients] vs 13.9% [734 of 5284 patients]; adjusted odds ratio [aOR] 0.83; 95% CI, 0.77-0.89; P < .001), more likely to have no major disability based on modified Rankin scale of 2 or less at discharge (28.5% [2415 of 8490 patients] vs 20.7% [894 of 4322 patients]; aOR, 1.36; 95% CI, 1.28-1.45; P < .001), and to have better reperfusion based on modified Thrombolysis in Cerebral Infarction grade 2b or greater (90.9% [8474 of 9318 patients] vs 88.0% [4140 of 4705 patients]; aOR, 1.39; 95% CI, 1.28-1.50; P < .001). However, alteplase treatment was associated with higher risk of sICH (6.5% [685 of 10 530 patients] vs 5.3% [279 of 5249 patients]; OR, 1.28; 95% CI, 1.16-1.42; P < .001).

Conclusions and Relevance

In this observational cohort study of patients treated with EVT, intravenous alteplase treatment was associated with better in-hospital survival and functional outcomes but higher sICH risk after adjusting for other covariates.

Determinants of Symptomatic Intracranial Hemorrhage After Endovascular Stroke Treatment: A Retrospective Cohort Study

Symptomatic intracranial hemorrhage (sICH) is a serious complication after endovascular treatment for ischemic stroke. We aimed to identify determinants of its occurrence and location.

Efficacy and safety of endovascular treatment with or without intravenous alteplase in acute anterior circulation large vessel occlusion stroke: a meta-analysis of randomized controlled trials

OBJECTIVE

The current meta-analysis aimed to investigate the efficacy and safety of direct endovascular treatment (EVT) and bridging therapy (EVT with prior intravenous thrombolysis (IVT)) in patients with acute anterior circulation large vessel occlusion (LVO) stroke.

METHODS

This meta-analysis followed PRISMA guidelines. Eligible RCTs were identified through a systemic search of electronic databases (PubMed, Ovid, Web of Science, and Cochrane Library) from the inception dates to January 10, 2022. The pooled analyses were performed using RevMan 5.3 software. The primary outcome was functional outcome on the modified Rankin Scale (mRS) (range 0 to 5) at 90 days. The secondary outcomes included successful reperfusion, intracranial hemorrhage, and mortality (mRS 6) within 90 days.

RESULTS

A total of 4 RCTs involving 1633 patients were finally included. Findings of pooled analyses indicated that neither the primary outcomes (no disability (mRS 0), no significant disability despite some symptoms (mRS 1), slight disability (mRS 2), moderate disability (mRS 3), moderately severe disability (mRS 4), severe disability (mRS 5), excellent outcome (mRS 0-1), functional independence outcome (mRS 0-2), and poor outcome (mRS 3-5)) nor the secondary outcomes (successful reperfusion, intracranial hemorrhage, and mortality) in the EVT groups were not statistically significant compared with the IVT plus EVT groups (P > 0.05). In addition, the outcomes of sensitivity analysis implied that the findings of meta-analysis were credible.

CONCLUSIONS

Among patients with acute ischemic stroke due to LVO of anterior circulation, EVT alone yielded efficacy and safety outcomes similar to IVT plus EVT.

Role of Intravenous Thrombolytics Prior to Endovascular Thrombectomy

Intravenous thrombolytics and endovascular thrombectomy for ischemic stroke have evolved in parallel. However, the best approach to combine these reperfusion therapies in patients eligible for both strategies remains uncertain. Initial randomized trials of endovascular thrombectomy included administration of intravenous thrombolytics to all eligible patients. However, whether that is of net benefit has been questioned and parallels drawn with treatment of ST-segment-elevation myocardial infarction, where intravenous thrombolytics are only given if first medical contact to percutaneous intervention is expected to be >90 minutes. Six randomized trials of a direct thrombectomy approach versus intravenous thrombolytics followed by endovascular thrombectomy have now reported their results. With exception of a minority of patients in one trial, the trials all used alteplase rather than potentially more effective tenecteplase. This review examines the current state of evidence and implications for clinical practice. Importantly, these trials only apply to patients who present to a hospital with immediate access to endovascular thrombectomy and are not relevant to patients who receive thrombolytic and are then transferred to an endovascular-capable hospital. Although 2 of the 6 randomized trials met their prespecified noninferiority margin, these margins were large compared with the absolute benefit of alteplase. Overall, functional outcome was similar, with slight trends favoring bridging thrombolytics and a significant increase in final reperfusion. Symptomatic hemorrhage was increased by ≈1.8% in the bridging group but death was nonsignificantly lower. The workflow in direct thrombectomy trials involved delaying thrombolytic administration until eligibility for thrombectomy and the trials was established and randomization completed. This reduced the time available for thrombolytics to occur prethrombectomy compared with standard practice. We conclude that, pending individual-patient data meta-analyses, intravenous thrombolytics retain an important role alongside endovascular thrombectomy. Further efforts to accelerate and enhance reperfusion with thrombolytics and perform individual patient-level pooled subgroup analyses are warranted.