Objective
This study was undertaken to investigate whether adjunct alteplase improves brain reperfusion following successful thrombectomy.
Methods
This single‐center, randomized, double‐blind, ...placebo‐controlled study included 36 patients (mean standard deviation = 70.8 13.5 years old, 18 50% women) with large vessel occlusion undergoing thrombectomy resulting in near‐normal (expanded Thrombolysis in Cerebral Infarction eTICI b50/67/2c, n = 23, 64%) or normal angiographic reperfusion (eTICI 3, n = 13, 36%). Seventeen patients were randomized to intra‐arterial alteplase (0.225mg/kg), and 19 received placebo. At 48 hours, patients had brain perfusion/diffusion‐weighted magnetic resonance imaging (MRI) and MRI‐spectroscopy. The primary outcome was the difference in the proportion of patients with areas of hypoperfusion on MRI. Secondary outcomes were the infarct expansion ratio (final to initial infarction volume), and the N‐acetylaspartate (NAA) peak relative to total creatine as a marker of neuronal integrity.
Results
The prevalence of hypoperfusion was 24% with intra‐arterial alteplase, and 58% with placebo (adjusted odds ratio = 0.20, 95% confidence interval CI = 0.04–0.91, p = 0.03). Among 14 patients with final eTICI 3 scores, hypoperfusion was found in 1 of 7 (14%) in the alteplase group and 3 of 7 (43%) in the placebo group. Abnormal brain perfusion was associated with worse functional outcome at day 90. Alteplase significantly reduced the infarct expansion ratio compared with placebo (median interquartile range (IQR) = 0.7 0.5–1.2 vs 3.2 1.8–5.7, p = 0.01) and resulted in higher NAA peaks (median IQR = 1.13 0.91–1.36 vs 1.00 0.74–1.22, p < 0.0001).
Interpretation
There is a high prevalence of areas of hypoperfusion following thrombectomy despite successful reperfusion on angiography. Adjunct alteplase enhances brain reperfusion, which results in reduced expansion of the infarction and improved neuronal integrity. ANN NEUROL 2022;92:860–870
Summary Introduction Uric acid is an antioxidant with neuroprotective effects in experimental models of stroke. We assessed whether uric acid therapy would improve functional outcomes at 90 days in ...patients with acute ischaemic stroke. Methods URICO-ICTUS was a randomised, double-blind, placebo-controlled, phase 2b/3 trial that recruited patients with acute ischaemic stroke admitted to ten Spanish stroke centres. Patients were included if they were aged 18 years or older, had received alteplase within 4·5 h of symptom onset, and had an eligible National Institutes of Health Stroke Scale (NIHSS) score (>6 and ≤25) and premorbid (assessed by anamnesis) modified Rankin Scale (mRS) score (≤2). Patients were randomly allocated (1:1) to receive uric acid 1000 mg or placebo (both infused intravenously in 90 min during the infusion of alteplase), stratified by centre and baseline stroke severity. The primary outcome was the proportion of patients with excellent outcome (ie, an mRS score of 0–1, or 2 if premorbid score was 2) at 90 days, analysed in the target population (all randomly assigned patients who had been correctly diagnosed with ischaemic stroke and had begun study medication). The study is registered with ClinicalTrials.gov , number NCT00860366. Findings Between July 1, 2011, and April 30, 2013, we randomly assigned 421 patients, of whom 411 (98%) were included in the target population (211 received uric acid and 200 received placebo). 83 (39%) patients who received uric acid and 66 (33%) patients who received placebo had an excellent outcome (adjusted risk ratio 1·23 95% CI 0·96–1·56; p=0·099). No clinically relevant or statistically significant differences were reported between groups with respect to death (28 13% patients who received uric acid vs 31 16% who received placebo), symptomatic intracerebral haemorrhage (nine 4% vs six 3%), and gouty arthritis (one <1% vs four 2%). 516 adverse events occurred in the uric acid group and 532 in the placebo group, of which 61 (12%) and 67 (13%), respectively, were serious adverse events (p=0·703). Interpretation The addition of uric acid to thrombolytic therapy did not increase the proportion of patients who achieved excellent outcome after stroke compared with placebo, but it did not lead to any safety concerns. Funding Institute of Health Carlos III of the Spanish Ministry of Health and Fundación Doctor Melchor Colet.
BACKGROUND AND PURPOSE—Computed tomographic (CT) high attenuation (HA) areas after endovascular therapy for acute ischemic stroke are a common finding indicative of blood–brain barrier disruption. ...Dual-energy CT allows an accurate differentiation between HA areas related to contrast staining (CS) or to brain hemorrhage (BH). We sought to evaluate the prognostic significance of the presence of CS and BH after endovascular therapy.
METHODS—A prospective cohort of 132 patients treated with endovascular therapy was analyzed. According to dual-energy CT findings, patients were classified into 3 groupsno HA areas (n=53), CS (n=32), and BH (n=47). The rate of new hemorrhagic transformations was recorded at follow-up neuroimaging. Clinical outcome was evaluated at 90 days with the modified Rankin Scale (poor outcome, 3–6).
RESULTS—Poor outcome was associated with the presence of CS (odds ratio OR, 11.3; 95% confidence interval, 3.34–38.95) and BH (OR, 10.4; 95% confidence interval, 3.42–31.68). The rate of poor outcome despite complete recanalization was also significantly higher in CS (OR, 9.7; 95% confidence interval, 2.55–37.18) and BH (OR, 15.1; 95% confidence interval, 3.85–59.35) groups, compared with the no-HA group. Patients with CS disclosed a higher incidence of delayed hemorrhagic transformation at follow-up (OR, 4.5; 95% confidence interval, 1.22–16.37) compared with no-HA patients.
CONCLUSIONS—Blood–brain barrier disruption, defined as CS and BH on dual-energy CT, was associated with poor clinical outcomes in patients with stroke treated with endovascular therapies. Moreover, isolated CS was associated with delayed hemorrhagic transformation. These results support the clinical relevance of blood–brain barrier disruption in acute stroke.
Revascularization after endovascular therapy for acute ischemic stroke is measured by the Thrombolysis In Cerebral Infarction (TICI) scale, yet variability exists in scale definitions. We examined ...the degree of reperfusion with the expanded TICI (eTICI) scale and association with outcomes in the HERMES collaboration of recent endovascular trials.
The HERMES Imaging Core, blind to all other data, evaluated angiography after endovascular therapy in HERMES. A battery of TICI scores (mTICI, TICI, TICI2C) was used to define reperfusion of the initial target occlusion defined by non-invasive imaging and conventional angiography.
Angiography of 801 subjects was available, including 797 defined by non-invasive imaging (154 internal carotid artery (ICA), 583 M1, 60 M2) and 748 by conventional angiography (195 ICA, 459 M1, 94 M2). Among 729 subjects in whom the reperfusion grade could be established, using eTICI (3=100%, 2C=90-99%, 2b67=67-89%, 2b50=50-66%) of the conventional angiography target occlusion, there were 63 eTICI 3 (9%), 166 eTICI 2c (23%), 218 eTICI 2b67 (30%), 103 eTICI 2b50 (14%), 100 eTICI 2a (14%), 19 eTICI 1 (3%), and 60 eTICI 0 (8%). Modified Rankin Scale shift analyses from baseline to 90 days showed that increasing TICI grades were linked with better outcomes, with significant distinctions between TICI 0/1 versus 2a (p=0.028), 2a versus 2b50 (p=0.017), and 2b50 versus 2b67 (p=0.014).
The benefit of endovascular therapy in HERMES was strongly associated with increasing degrees of reperfusion defined by eTICI. The eTICI metric identified meaningful distinctions in clinical outcomes and may be used in future studies and routine practice.
Anatomical labeling of the cerebral arteries forming the Circle of Willis (CoW) enables inter-subject comparison, which is required for geometric characterization and discovering risk factors ...associated with cerebrovascular pathologies. We present a method for automated anatomical labeling of the CoW by detecting its main bifurcations. The CoW is modeled as rooted attributed relational graph, with bifurcations as its vertices, whose attributes are characterized as points on a Riemannian manifold. The method is first trained on a set of pre-labeled examples, where it learns the variability of local bifurcation features as well as the variability in the topology. Then, the labeling of the target vasculature is obtained as maximum a posteriori probability (MAP) estimate where the likelihood of labeling individual bifurcations is regularized by the prior structural knowledge of the graph they span. The method was evaluated by cross-validation on 50 subjects, imaged with magnetic resonance angiography, and showed a mean detection accuracy of 95%. In addition, besides providing the MAP, the method can rank the labelings. The proposed method naturally handles anatomical structural variability and is demonstrated to be suitable for labeling arterial segments of the CoW.
Whether reperfusion into infarcted tissue exacerbates cerebral edema has treatment implications in patients presenting with extensive irreversible injury. We investigated the effects of endovascular ...thrombectomy and reperfusion on cerebral edema in patients presenting with radiological evidence of large hemispheric infarction at baseline.
In a systematic review and individual patient-level meta-analysis of 7 randomized controlled trials comparing thrombectomy versus medical therapy in anterior circulation ischemic stroke published between January 1, 2010, and May 31, 2017 (Highly Effective Reperfusion Using Multiple Endovascular Devices collaboration), we analyzed the association between thrombectomy and reperfusion with maximal midline shift (MLS) on follow-up imaging as a measure of the space-occupying effect of cerebral edema in patients with large hemispheric infarction on pretreatment imaging, defined as diffusion-magnetic resonance imaging or computed tomography (CT)-perfusion ischemic core 80 to 300 mL or noncontrast CT-Alberta Stroke Program Early CT Score ≤5. Risk of bias was assessed using the Cochrane tool.
Among 1764 patients, 177 presented with large hemispheric infarction. Thrombectomy and reperfusion were associated with functional improvement (thrombectomy common odds ratio =2.30 95% CI, 1.32–4.00; reperfusion common odds ratio =4.73 95% CI, 1.66–13.52) but not MLS (thrombectomy β=−0.27 95% CI, −1.52 to 0.98; reperfusion β=−0.78 95% CI, −3.07 to 1.50) when adjusting for age, National Institutes of Health Stroke Score, glucose, and time-to-follow-up imaging. In an exploratory analysis of patients presenting with core volume >130 mL or CT-Alberta Stroke Program Early CT Score ≤3 (n=76), thrombectomy was associated with greater MLS after adjusting for age and National Institutes of Health Stroke Score (β=2.76 95% CI, 0.33–5.20) but not functional improvement (odds ratio, 1.71 95% CI, 0.24–12.08).
In patients presenting with large hemispheric infarction, thrombectomy and reperfusion were not associated with MLS, except in the subgroup with very large core volume (>130 mL) in whom thrombectomy was associated with increased MLS due to space-occupying ischemic edema. Mitigating cerebral edema-mediated secondary injury in patients with very large infarcts may further improve outcomes after reperfusion therapies.
We sought to explore the safety and efficacy of the new TREVO stent-like retriever in consecutive patients with acute stroke.
We conducted a prospective, single-center study of 60 patients (mean age, ...71.3 years; male 47%) with stroke lasting <8 hours in the anterior circulation (n=54) or <12 hours in the vertebrobasilar circulation (n=6) treated if CT perfusion/CT angiography confirmed a large artery occlusion, ruled out a malignant profile, or showed target mismatch if symptoms >4.5 hours. Successful recanalization (Thrombolysis In Cerebral Infarction 2b-3), good outcome (modified Rankin Scale score 0-2) and mortality at Day 90, device-related complications, and symptomatic hemorrhage (parenchymal hematoma Type 1 or parenchymal hematoma Type 2 and National Institutes of Health Stroke Scale score increment ≥ 4 points) were prospectively assessed.
Median (interquartile range) National Institutes of Health Stroke Scale score on admission was 18 (12-22). The median (interquartile range) time from stroke onset to groin puncture was 210 (173-296) minutes. Successful revascularization was obtained in 44 (73.3%) of the cases when only the TREVO device was used and in 52 (86.7%) when other devices or additional intra-arterial tissue-type plasminogen activator were also required. The median time (interquartile range) of the procedure was 80 (45-114) minutes. Good outcome was achieved in 27 (45%) of the patients and the mortality rate was 28.3%. Seven patients (11.7%) presented a symptomatic intracranial hemorrhage. No other major complications were detected.
The TREVO device was reasonably safe and effective in patients with severe stroke. These results support further investigation of the TREVO device in multicentric registries and randomized clinical trials.
Current guidelines for ischaemic stroke treatment recommend a strict, but arbitrary, upper threshold of 185/110 mm Hg for blood pressure before endovascular thrombectomy. Nevertheless, whether ...admission blood pressure influences the effect of endovascular thrombectomy on outcome remains unknown. Our aim was to study the influence of admission systolic blood pressure (SBP) on functional outcome and on the effect of endovascular thrombectomy.
We used individual patient data from seven randomised controlled trials (MR CLEAN, ESCAPE, EXTEND-IA, SWIFT PRIME, REVASCAT, PISTE, and THRACE) that randomly assigned patients with anterior circulation ischaemic stroke to endovascular thrombectomy (predominantly using stent retrievers) or standard medical therapy (control) between June 1, 2010, and April 30, 2015. We included all patients for whom SBP data were available at hospital admission. The primary outcome was functional outcome (modified Rankin Scale) at 90 days. We assessed the association of SBP with outcome in both the endovascular thrombectomy group and the control group using multilevel regression analysis and tested for non-linearity and for interaction between SBP and effect of endovascular thrombectomy, taking into account treatment with intravenous thrombolysis.
We included 1753 patients (867 assigned to endovascular thrombectomy, 886 assigned to control) after excluding 11 patients for whom SBP data were missing. We found a non-linear association between SBP and functional outcome with an inflection point at 140 mm Hg (732 42% of 1753 patients had SBP <140 mm Hg and 1021 58% had SBP ≥140 mm Hg). Among patients with SBP of 140 mm Hg or higher, admission SBP was associated with worse functional outcome (adjusted common odds ratio acOR 0·86 per 10 mm Hg SBP increase; 95% CI 0·81–0·91). We found no association between SBP and functional outcome in patients with SBP less than 140 mm Hg (acOR 0·97 per 10 mm Hg SBP decrease, 95% CI 0·88–1·05). There was no significant interaction between SBP and effect of endovascular thrombectomy on functional outcome (p=0·96).
In our meta-analysis, high admission SBP was associated with worse functional outcome after stroke, but SBP did not seem to negate the effect of endovascular thrombectomy. This finding suggests that admission SBP should not form the basis for decisions to withhold or delay endovascular thrombectomy for ischaemic stroke, but randomised trials are needed to further investigate this possibility.
Medtronic.