Alberta Stroke Program Early CT Research Articles

Acute ischemic stroke with or without asymptomatic intracranial hemorrhage after endovascular treatment: a propensity-score matching study

BackgroundThe long-term follow-up of asymptomatic intracranial hemorrhage (aICH) in patients with acute ischemic stroke after endovascular treatment (EVT) remains controversial.ObjectiveTo evaluate the potential effect of aICH in a real-world practice...

The impact of general anesthesia versus non-general anesthesia on thrombectomy outcomes by occlusion location: insights from the ETIS registry.

Identifying the optimal anesthetic technique for mechanical thrombectomy (MT) remains an unresolved issue. Prior research has not considered the influence of occlusion site when comparing general anesthesia (GA) with non-GA. This study evaluates the differential impacts of the anesthetic technique (GA vs non-GA) on outcomes according to the location of occlusion. This is a retrospective analysis of the ETIS (Endovascular Treatment in Ischemic Stroke) registry. Patients with anterior circulation large-vessel occlusion treated with MT were included. Patients were divided into groups according to the location of occlusion. Inverse propensity score weighting analysis was used. Among 2783 patients included in the propensity score analysis, 669 (24%) received GA. In the total cohort, GA was not associated with favorable outcome, excellent outcome, successful reperfusion, or complete reperfusion. GA was associated with higher odds of parenchymal hemorrhage (OR 1.42, 95% 1.05-1.92) but not symptomatic intracranial hemorrhage. GA was associated with Alberta Stroke Program Early CT Score progression (OR 1.36, 95% CI 1.11-1.68). In the internal carotid artery occlusion group, GA was associated with higher odds of mortality (OR 1.94, 95% CI 1.15-3.27). In the M1 group, GA was associated with lower odds of complications (OR 0.41, 95% CI 0.19-0.92). In the M2 group, GA was associated with successful reperfusion (OR 2.79, 95% CI 1.02-7.64). In addition, the complication rate was lower with GA (2.7% vs 7%), although the association was not significant in adjusted analysis. While GA and non-GA techniques did not differ significantly in functional outcomes, the influence of GA on angiographic and procedural safety outcomes was location dependent, underscoring the importance of a tailored anesthesia technique in MT procedures.

Haemorrhage after thrombectomy with adjuvant thrombolysis in unknown onset stroke depends on high early lesion water uptake

Background and purposeIn wake-up stroke, CT-based quantitative net water uptake (NWU) might serve as an alternative tool to MRI to guide intravenous thrombolysis with alteplase (IVT). An important complication after...

Role of mechanical thrombectomy among large vessel stroke patients during the coronavirus disease (COVID-19) pandemic

PurposeThe aim of our study is to provide insights derived from experience at multiple centers regarding the outcomes of mechanical thrombectomy (MT) for large vessel occlusion (LVO) in COVID-19 patients and compare them with those in non-COVID-19 patients during the coronavirus disease (COVID-19) pandemic.ResultsCOVID‐19 positive patients were younger than COVID‐19 negative patients (62.1 ± 2.69 versus 69.5 ± 2.2, P < 0.001). There was a significant difference between COVID-19 and non-COVID-19 groups in the median D-dimer levels (6 vs. 4.5; P < 0.001), median ESR levels (63 vs. 38; P < 0.001) and median CRP levels (110 vs. 48.5; P < 0.001), respectively. Median time from stroke symptoms onset to hospital admission was significantly higher among COVID-19 positive patients (366 vs. 155 min; P < 0.001). COVID‐19 positive patients with LVO presented with a higher median NIH Stroke Scale score at presentation (16 versus 8, P < 0.001) and lower median Alberta Stroke Program Early CT Score (ASPECTS) on admission (6 versus 8, P < 0.001). Patients with COVID-19 had significantly higher percentages of poor functional outcomes as scored using the mRS grades 3–5 in comparison to non-COVID-19 patients (69.2% vs. 13.6%; P = 0.002), but there was no significant difference between both groups in complications such as early cerebral re-occlusion, intracerebral hemorrhage, or in-hospital mortality (P > 0.05).ConclusionMechanical thrombectomy has effectively managed patients with LVO stroke. LVO stroke in COVID-19 patients occur at a young age, and have multi-territory vascular involvement. Poor functional outcomes post thrombectomy in COVID-19 patients, irrespective of timely, successful angiographic recanalization.

Deep learning-based automatic ASPECTS calculation can improve diagnosis efficiency in patients with acute ischemic stroke: a multicenter study.

The Alberta Stroke Program Early CT Score (ASPECTS), a systematic method for assessing ischemic changes in acute ischemic stroke using non-contrast computed tomography (NCCT), is often interpreted relying on expert experience and can vary between readers. This study aimed to develop a clinically applicable automatic ASPECTS system employing deep learning (DL). This study enrolled 1987 NCCT scans that were retrospectively collected from four centers between January 2017 and October 2021. A DL-based system for automated ASPECTS assessment was trained on a development cohort (N = 1767) and validated on an independent test cohort (N = 220). The consensus of experienced physicians was regarded as a reference standard. The validity and reliability of the proposed system were assessed against physicians' readings. A real-world prospective application study with 13,399 patients was used for system validation in clinical contexts. The DL-based system achieved an area under the receiver operating characteristic curve (AUC) of 84.97% and an intraclass correlation coefficient (ICC) of 0.84 for overall-level analysis on the test cohort. The system's diagnostic sensitivity was 94.61% for patients with dichotomized ASPECTS at a threshold of ≥ 6, with substantial agreement (ICC = 0.65) with expert ratings. Combining the system with physicians improved AUC from 67.43 to 89.76%, reducing diagnosis time from 130.6 ± 66.3 s to 33.3 ± 8.3 s (p < 0.001). During the application in clinical contexts, 94.0% (12,591) of scans successfully processed by the system were utilized by clinicians, and 96% of physicians acknowledged significant improvement in work efficiency. The proposed DL-based system could accurately and rapidly determine ASPECTS, which might facilitate clinical workflow for early intervention. The deep learning-based automated ASPECTS evaluation system can accurately and rapidly determine ASPECTS for early intervention in clinical workflows, reducing processing time for physicians by 74.8%, but still requires validation by physicians when in clinical applications. The deep learning-based system for ASPECTS quantification has been shown to be non-inferior to expert-rated ASPECTS. This system improved the consistency of ASPECTS evaluation and reduced processing time to 33.3 seconds per scan. 94.0% of scans successfully processed by the system were utilized by clinicians during the prospective clinical application.

Mechanical Thrombectomy in Ischemic Stroke with a Large Infarct Core: A Meta-Analysis of Randomized Controlled Trials.

Background/Objectives: Endovascular treatment (EVT) is recommended for acute ischemic stroke due to large-vessel occlusion (LVO) and an Alberta Stroke Program Early CT Score (ASPECTS) ≥ 6. Randomized controlled trials (RCTs) have recently become available on EVT effects in people with LVO-related large core stroke (ASPECTS 0-5). Here, we provide an updated meta-analysis of the EVT effect on functional neurological status in people with large-core stroke. Methods: The study followed the PRISMA guidelines. PubMed, EMBASE and Cochrane Central were searched for RCTs comparing EVT vs. best medical treatment (BMT) in large-core LVO stroke. The primary outcome was functional independence at 90 days (modified Rankin Scale; mRS 0-2). The secondary outcomes were symptomatic intracranial hemorrhage (sICH), good functional outcome (mRS 0-3) and excellent functional outcome (mRS 0-1). EVT vs. BMT was compared through random effect meta-analysis. Heterogeneity was assessed with the I2 and Q test and risk of bias reported according to the RoB2 tool. Results: Six RCTs were included (n = 1656 patients). All studies had a moderate risk of bias, with blinding bias due to the nature of the intervention, potential allocation bias and incomplete outcome reporting. Functional independence was significantly more frequent in the EVT vs. BMT group (OR = 2.47, 95% CI = 1.52-4.03, p < 0.001). sICH rates (OR = 1.77, 95% CI = 1.01-3.11, p = 0.04) and good functional outcome (OR = 2.20; 95% CI = 1.72-2.81, p < 0.001) were more frequent in the EVT vs. BMT group, while the rates of mRS 0-1 did not differ. Conclusions: In patients with large-core stroke and LVO, EVT plus BMT as compared to BMT alone carries a significant increase in independent ambulation and good functional outcome at 3 months despite the marginal increase in sICH.

Safety and efficacy of tirofiban combined with intravenous thrombolysis and endovascular treatment in acute large vessel occlusion stroke

ObjectiveThis study assesses the safety and efficacy of tirofiban for patients with large vessel occlusion stroke after intravenous thrombolysis. MethodsThis study data was from SUSTAIN, DEVT, and RESCUE BT trials. According to whether the use of tirofiban who underwent endovascular treatment and preceding intravenous thrombolysis was divided into the tirofiban group and the no-tirofiban group. The safety outcomes were symptomatic intracranial hemorrhage, any intracranial hemorrhage within 48 h, and 3-month mortality. The efficacy outcome was defined as a score of 0–2 on the modified Rankin Scale scores at 3 months. ResultsA total of 372 patients with intravenous thrombolysis were included in these SUSTAIN, DEVT, and RESCUE BT trials. Adjusted multivariate analysis showed that tirofiban with intravenous thrombolysis was not associated with symptomatic intracranial hemorrhage (aOR, 0.87; 95 % CI, 0.49–1.57; P=0.65), any intracranial hemorrhage within 48 h (aOR, 1.00; 95 % CI, 0.60–1.66; P=1.00), 3-month mortality (aOR, 1.10; 95 % CI, 0.56–2.19; P=0.78) and 3-month modified Rankin Scale scores 0–2 (aOR, 0.72; 95 % CI, 0.42–1.25; P=0.25) in patients with acute large vessel occlusion. In the subgroup analysis, we found that tirofiban was not recommended for females (aOR, 0.34; 95 % CI, 0.12–0.93), baseline Alberta Stroke Program Early CT Score≤9 (aOR, 0.37; 95 % CI, 0.18–0.76), and cardiogenic embolism (aOR, 0.36; 95 % CI, 0.14–0.97). ConclusionTirofiban combined with intravenous thrombolysis in patients with acute large vessel occlusion may be safe. Further studies need to confirm the effectiveness of tirofiban after intravenous thrombolysis in different stroke etiology.

Collaterals at angiography guide clinical outcomes after endovascular stroke therapy in HERMES

BackgroundRobust collateral circulation has been linked with better reperfusion and clinical outcomes. It remains unclear how individual assessments of collateral circulation may be translated into clinical practice.MethodsThe pooled Highly Effective...

Functional Outcome and Hemorrhage Rates After Bridging Therapy With Tenecteplase or Alteplase in Patients With Large Ischemic Core.

IV tenecteplase is an alternative to alteplase before mechanical thrombectomy (MT) in patients with large-vessel occlusion (LVO) ischemic stroke. Little data are available on its use in patients with large ischemic core. We aimed to compare the efficacy and safety of both thrombolytics in this population. We conducted a retrospective analysis of patients with anterior circulation LVO strokes and diffusion-weighed imaging Alberta Stroke Program Early CT Score (DWI-ASPECTS) ≤5 treated with tenecteplase or alteplase before MT from the TETRIS (tenecteplase) and ETIS (alteplase) French multicenter registries. Primary outcome was reduced disability at 3 months (ordinal analysis of the modified Rankin scale [mRS]). Safety outcomes were 3-month mortality, parenchymal hematoma (PH), and symptomatic intracranial hemorrhage (sICH). We used propensity score overlap weighting to reduce baseline differences between treatment groups. We analyzed 647 patients (tenecteplase: n = 194; alteplase: n = 453; inclusion period 2015-2022). Median (interquartile range) age was 71 (57-81) years, with NIH Stroke Scale score 19 (16-22), DWI-ASPECTS 4 (3-5), and last seen well-to-IV thrombolysis and puncture times 165 minutes (130-226) and 260 minutes (203-349), respectively. After MT, the successful reperfusion rate was 83.1%. After propensity score overlap weighting, all baseline variables were well balanced between both treatment groups. Compared with patients treated with alteplase, patients treated with tenecteplase had better 3-month mRS (common odds ratio [OR] for reduced disability: 1.37, 1.01-1.87, p = 0.046) and lower 3-month mortality (OR 0.52, 0.33-0.81, p < 0.01). There were no significant differences between thrombolytics for PH (OR 0.84, 0.55-1.30, p = 0.44) and sICH incidence (OR 0.70, 0.42-1.18, p = 0.18). Our data are encouraging regarding the efficacy and reassuring regarding the safety of tenecteplase compared with that of alteplase in bridging therapy for patients with LVO strokes and a large ischemic core in routine clinical care. These results support its consideration as an alternative to alteplase in bridging therapy for patients with large ischemic cores. NCT03776877 (ETIS registry) and NCT05534360 (TETRIS registry). This study provides Class III evidence that patients with anterior circulation LVO stroke and DWI-ASPECTS ≤5 treated with tenecteplase vs alteplase before MT experienced better functional outcomes and lower mortality at 3 months.

Thrombus age does not differentiate between cardiogenic and atherosclerotic strokes

ObjectiveInterventional stroke therapy made thrombi available for histological analysis. Unfortunately, simple composition aspects such as erythrocyte versus fibrin/platelet rich did not allow a feasible allocation to thrombi’s cardiac or carotid...

Neurological outcomes for patients meeting radiographic criteria for DEFUSE 3 and SELECT2

BackgroundThe DEFUSE 3 and SELECT2 thrombectomy trials included some patients with similar radiographic profiles, although the rates of good functional outcomes differed widely between the studies.ObjectiveTo report neurological outcomes for...

Days Alive and Out of Hospital as an Outcome Measure in Patients Receiving Hyperacute Stroke Intervention.

Patient outcome after stroke is frequently assessed with clinical scales such as the modified Rankin Scale score (mRS). Days alive and out of hospital at 90 days (DAOH-90), which measures survival, time spent in hospital or rehabilitation settings, readmission and institutionalization, is an objective outcome measure that can be obtained from large administrative data sets without the need for patient contact. We aimed to assess the comparability of DAOH with mRS and its relationship with other prognostic variables after acute stroke reperfusion therapy. Consecutive patients with ischemic stroke treated with intravenous thrombolysis or endovascular thrombectomy were analyzed. DAOH-90 was calculated from a national minimum data set, a mandatory nationwide administrative database. mRS score at day 90 (mRS-90) was assessed with in-person or telephone interviews. The study included 1278 patients with ischemic stroke (714 male, median age 70 [59-79], median National Institutes of Health Stroke Scale score 14 [9-20]). Median DAOH-90 was 71 [29-84] and median mRS-90 score was 3 [2-5]. DAOH-90 was correlated with admission National Institutes of Health Stroke Scale score (Spearman rho -0.44, P<0.001) and Alberta Stroke Program Early CT [Computed Tomography] Score (Spearman rho 0.24, P<0.001). There was a strong association between mRS-90 and DAOH-90 (Spearman rho correlation -0.79, P<0.001). Area under receiver operating curve for predicting mRS score >0 was 0.86 (95% CI, 0.84-0.88), mRS score >1 was 0.88 (95% CI, 0.86-0.90) and mRS score >2 was 0.90 (95% CI, 0.89-0.92). In patients with stroke treated with reperfusion therapies, DAOH-90 shows reasonable comparability to the more established outcome measure of mRS-90. DAOH-90 can be readily obtained from administrative databases and therefore has the potential to be used in large-scale clinical trials and comparative effectiveness studies.

Safety of acute internal carotid artery stenting during endovascular thrombectomy in patients with acute ischemic stroke: a retrospective analysis of the OPTIMISE registry

BackgroundThe optimal management of tandem carotid lesions during endovascular thrombectomy (EVT) remains uncertain. The safety and efficacy of acute carotid artery stenting (aCAS) are debated, including safety concerns such as...

Prognostic value of combining 24-hour ASPECTS and hemoglobin to red cell distribution width ratio to the THRIVE score in predicting in-hospital mortality among ischemic stroke patients treated with intravenous thrombolysis.

Acute ischemic stroke (AIS) is a significant global health issue, directly impacting mortality and disability. The Totaled Health Risks in Vascular Events (THRIVE) score is appreciated for its simplicity and ease of use to predict stroke clinical outcomes; however, it lacks laboratory and neuroimaging data, which limits its ability to predict outcomes precisely. Our study evaluates the impact of integrating the 24-hour Alberta Stroke Program Early CT Score (ASPECTS) and hemoglobin-to-red cell distribution width (HB/RDW) ratio into the THRIVE score using the multivariable fractional polynomial (MFP) method (combined THRIVE-MFP model) compared to the THRIVE-c model. We aim to assess their added value in predicting in-hospital mortality (IHM) prognosis. A retrospective study from January 2015 to July 2022 examined consecutive AIS patients receiving intravenous thrombolysis. Data on THRIVE scores, 24-hour ASPECTS, and HB/RDW levels were collected upon admission. The model was constructed using logistic regression and the MFP method. The prognostic value was determined using the area under the receiver operating characteristic curve (AuROC). Ischemic cerebral lesions within the middle cerebral artery territory were evaluated with non-contrast computed tomography (NCCT) after completing 24 hours of intravenous thrombolysis (24-hour ASPECTS). Among a cohort of 345 patients diagnosed with AIS who received intravenous thrombolysis, 65 individuals (18.8%) experienced IHM. The combined THRIVE-MFP model was significantly superior to the THRIVE-c model in predicting IHM (AuROC 0.980 vs. 0.876, p<0.001), 3-month mortality (AuROC 0.947 vs. 0.892, p<0.001), and 3-month poor functional outcome (AuROC 0.910 vs. 0.853, p<0.001). The combined THRIVE-MFP model showed excellent predictive performance, enhancing physicians' ability to stratify patient selection for intensive neurological monitoring and guiding treatment decisions. Incorporating 24-hour ASPECTS on NCCT and HB/RDW proved valuable in mortality prediction, particularly for hospitals with limited access to advanced neuroimaging resources.

Dual-Energy CT in Acute Stroke: Could Non-Contrast CT Be Replaced by Virtual Non-Contrast CT? A Feasibility Study.

Purpose: We aimed to evaluate whether virtual non-contrast cerebral computed tomography (VNCCT) reconstructed from intravenous contrast-enhanced dual-energy CT (iv-DECT) could replace non-contrast CT (NCCT) in patients with suspected acute cerebral ischemia. Method: This retrospective study included all consecutive patients in whom NCCT followed by iv-DECT were performed for suspected acute ischemia in our emergency department over a 1-month period. The Alberta Stroke Program Early CT Score (ASPECTS) was used to determine signs of acute ischemia in the anterior and posterior circulation, the presence of hemorrhage, and alternative findings, which were randomly evaluated via the consensus reading of NCCT and VNCCT by two readers blinded to the final diagnosis. An intraclass correlation between VNCCT and NCCT was calculated for the ASPECTS values. Both techniques were evaluated for their ability to detect ischemic lesions (ASPECTS <10) when compared with the final discharge diagnosis (reference standard). Results: Overall, 148 patients (80 men, mean age 64 years) were included, of whom 46 (30%) presented with acute ischemia, 6 (4%) presented with intracerebral hemorrhage, 11 (7%) had an alternative diagnosis, and 85 (59%) had no pathological findings. The intraclass correlation coefficients of the two modalities were 0.97 (0.96-0.98) for the anterior circulation and 0.77 (0.69-0.83) for the posterior circulation. The VNCCT's sensitivity for detecting acute ischemia was higher (41%, 19/46) than that of NCCT (33%, 15/46). Specificity was similar between the two techniques, at 94% (97/103) and 98% (101/103), respectively. Conclusions: Our results show that VNCCT achieved a similar diagnostic performance as NCCT and could, thus, replace NCCT in assessing patients with suspected acute cerebral ischemia.

Endovascular thrombectomy with or without intravenous alteplase in large-core ischemic stroke: a systematic review and meta-analysis.

The role of bridging intravenous thrombolysis (IVT) with alteplase before endovascular thrombectomy (EVT) in treating large core ischemic stroke remains uncertain. We aimed to compare clinical outcomes and safety of EVT with or without bridging IVT in patients with anterior circulation large vessel occlusion (ACLVO) and baseline Alberta Stroke Program Early CT Score (ASPECTS) ≤ 5. We systematically searched PubMed, Web of Science, Cochrane Library, and Embase from inception until November 2023. The primary outcome was 90-day functional independence (modified Rankin Scale [mRS] 0-2). Secondary outcomes included 90-day independent ambulation (mRS 0-3), successful recanalization, any intracranial hemorrhage (ICH), symptomatic ICH (sICH) and 90-day mortality. A random-effects model was used for data pooling. Five high-quality studies, incorporating 2124 patients (41% treated with bridging IVT), were included. Across both unadjusted and adjusted analyses, no significant differences were found between the bridging IVT and EVT-alone groups in terms of functional independence (odds ratios [OR] = 1.36, 95% confidence interval [CI]: 0.90-2.07, P = 0.14; adjusted OR [aOR] = 1.19, 95% CI: 0.68-2.09, P = 0.53) or independent ambulation (OR = 1.14, 95% CI: 0.80-1.62, P = 0.47; aOR = 1.18, 95% CI: 1.00-1.39, P = 0.05) at 90days. Furthermore, no differences were observed in successful recanalization, any ICH, sICH, and 90-day mortality between the two treatment groups. Bridging IVT exhibits similar functional and safety outcomes compared to EVT alone in ACLVO patients with baseline ASPECTS ≤ 5. Further research is warranted to confirm these findings.

Nomogram established on account of Lasso-logistic regression for predicting hemorrhagic transformation in patients with acute ischemic stroke after endovascular thrombectomy

BackgroundHemorrhagic transformation (HT) is a common and serious complication in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). This study was performed to determine the predictive factors associated with HT in stroke patients with EVT and to establish and validate a nomogram that combines with independent predictors to predict the probability of HT after EVT in patients with AIS. MethodsAll patients were randomly divided into development and validation cohorts at a ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) regression was used to select the optimal factors, and multivariate logistic regression analysis was used to build a clinical prediction model. Calibration plots, decision curve analysis (DCA) and receiver operating characteristic curve (ROC) were generated to assess predictive performance. ResultsLASSO regression analysis showed that Alberta Stroke Program Early CT Scores (ASPECTS), international normalized ratio (INR), uric acid (UA), neutrophils (NEU) were the influencing factors for AIS with HT after EVT. A novel prognostic nomogram model was established to predict the possibility of HT with AIS after EVT. The calibration curve showed that the model had good consistency. The results of ROC analysis showed that the AUC of the prediction model established in this study for predicting HT was 0.797 in the development cohort and 0.786 in the validation cohort. ConclusionThis study proposes a novel and practical nomogram based on ASPECTS, INR, UA, NEU, which can well predict the probability of HT after EVT in patients with AIS.

Clinical and safety outcomes of acute stenting plus thrombectomy for carotid tandem lesions with large ischemic core

BackgroundWe evaluated the clinical and safety outcomes of emergent carotid artery stenting (eCAS) plus endovascular thrombectomy (EVT) among patients with anterior tandem lesion (TL) and large ischemic core (LIC).MethodsThis retrospective...

Endovascular therapy of isolated posterior cerebral artery occlusion stroke with and without general anesthesia

BackgroundThe optimal anesthetic strategy for endovascular therapy (EVT) in acute ischemic stroke is still under debate. The aim of this study was to compare the clinical outcomes of patients with...

Number of passes and outcome of endovascular treatment of anterior circulation large core ischemic stroke: insights from the Endovascular Treatment in Ischemic Stroke (ETIS) registry

BackgroundThe effect of multiple attempts on the outcome of endovascular treatment (EVT) of anterior circulation large ischemic core (LIC) stroke has not been fully explored.MethodsWe analyzed data from the Endovascular...