Impact of pretreatment with intravenous thrombolysis on reperfusion status in acute strokes treated with mechanical thrombectomy

Effect of Clot Burden Score on Safety and Efficacy of Intravenous Alteplase Prior to Mechanical Thrombectomy in Acute Ischemic Stroke: A Subgroup Analysis of a Randomized Phase 3 Trial

BACKGROUND AND PURPOSE

Whether thrombus burden in acute ischemic stroke modify the effect of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remains uncertain. We aim to investigate the treatment effect of stratified clot burden score (CBS) on the efficacy and safety of direct versus bridging MT.

MATERIALS AND METHODS

This is an exploratory subgroup analysis of a randomized trial evaluating the effect of CBS on clinical outcome in the DIRECT-MT trial. CBS was divided into 3 groups (0-3, 4-6, and 7-10) based on preoperative CTA, where higher scores indicated a lower clot burden. We report the adjusted common odds ratio for a shift toward better outcomes on the mRS after thrombectomy alone compared with combination treatment by stratified CBS groups.

RESULTS

No modification effect of mRS distribution was observed by CBS subgroups (CBS 0-3: adjusted common ratio odds 1.519 [95% CI, 0.928-2.486]; 4-6: 0.924 [0.635-1.345]; 7-10: 1.040 [0.481-2.247]). Patients with CBS 4-6 had a higher rate of early reperfusion (adjusted OR (aOR), 0.3 [95% CI, 0.1-0.9]), final reperfusion (aOR 0.5 [95% CI, 0.3-0.9]), and fewer thrombectomy attempts (aOR 0.4 [95% CI, 0.1-0.7]). Patients with CBS 7-10 had a higher rate of asymptomatic intracranial hemorrhage (14.9% versus 36.8%, P = .0197) for bridging MT. No significant difference was observed in other safety outcomes by trichotomized CBS.

CONCLUSIONS

The subgroup analysis of DIRECT-MT suggested that thrombus burden did not alter the treatment effect of IVT before MT on functional outcomes in CBS subgroups.

Thrombectomy versus combined thrombolysis and thrombectomy in patients with large vessel occlusion and chronic kidney disease

Background

Whether intravenous thrombolysis (IVT) should be bridged before mechanical thrombectomy (MT) remains uncertain in patients with large vessel occlusion (LVO) and chronic kidney disease (CKD).

Methods

This research systematically enrolled every patient with both acute ischemic stroke (AIS) and CKD who received MT and fulfilled the criteria for IVT from January 2015 to December 2022. According to whether they underwent IVT, the patients were categorized into two cohorts: MT and combined IVT + MT. A binary logistic regression model was used to adjust for potential confounders, and propensity score matching analysis was used to assess the efficacy and safety of IVT in AIS patients with CKD who underwent MT.

Results

A total number of 406 patients were ultimately included in this study, with 236 patients in the MT group and 170 in the combined group. After PSM, there were 170 patients in the MT group and 170 in the combined group, and the clinical characteristics between the two groups were well balanced. The MT + IVT group had better long-term functional outcomes than the MT group (35.9% versus 21.2%, P = 0.003) and more modified thrombolysis in cerebral infarction (mTICI) (2b-3) (94.1% versus 87.6%, P = 0.038), while no significant difference was found regarding symptomatic intracranial hemorrhage (sICH). In line with the results observed in the in the postmatched population, the logistic regression revealed that patients in the IVT + MT group demonstrated superior clinical outcomes (adjusted OR 0.440 [95% CI (0.267-0.726)], P = 0.001) in the prematched population.

Conclusion

For LVO patients with CKD and indications for IVT, IVT bridging MT improves their prognosis compared with direct MT.

No-reflow after stroke reperfusion therapy: An emerging phenomenon to be explored

In the field of stroke thrombectomy, ineffective clinical and angiographic reperfusion after successful recanalization has drawn attention. Partial or complete microcirculatory reperfusion failure after the achievement of full patency of a former obstructed large vessel, known as the "no-reflow phenomenon" or "microvascular obstruction," was first reported in the 1960s and was later detected in both experimental models and patients with stroke. The no-reflow phenomenon (NRP) was reported to result from intraluminal occlusions formed by blood components and extraluminal constriction exerted by the surrounding structures of the vessel wall. More recently, an emerging number of clinical studies have estimated the prevalence of the NRP in stroke patients following reperfusion therapy, ranging from 3.3% to 63% depending on its evaluation methods or study population. Studies also demonstrated its detrimental effects on infarction progress and neurological outcomes. In this review, we discuss the research advances, underlying pathogenesis, diagnostic techniques, and management approaches concerning the no-reflow phenomenon in the stroke population to provide a comprehensive understanding of this phenomenon and offer references for future investigations.

Ischemia-reperfusion injury: molecular mechanisms and therapeutic targets

Ischemia-reperfusion (I/R) injury paradoxically occurs during reperfusion following ischemia, exacerbating the initial tissue damage. The limited understanding of the intricate mechanisms underlying I/R injury hinders the development of effective therapeutic interventions. The Wnt signaling pathway exhibits extensive crosstalk with various other pathways, forming a network system of signaling pathways involved in I/R injury. This review article elucidates the underlying mechanisms involved in Wnt signaling, as well as the complex interplay between Wnt and other pathways, including Notch, phosphatidylinositol 3-kinase/protein kinase B, transforming growth factor-β, nuclear factor kappa, bone morphogenetic protein, N-methyl-D-aspartic acid receptor-Ca2+-Activin A, Hippo-Yes-associated protein, toll-like receptor 4/toll-interleukine-1 receptor domain-containing adapter-inducing interferon-β, and hepatocyte growth factor/mesenchymal-epithelial transition factor. In particular, we delve into their respective contributions to key pathological processes, including apoptosis, the inflammatory response, oxidative stress, extracellular matrix remodeling, angiogenesis, cell hypertrophy, fibrosis, ferroptosis, neurogenesis, and blood-brain barrier damage during I/R injury. Our comprehensive analysis of the mechanisms involved in Wnt signaling during I/R reveals that activation of the canonical Wnt pathway promotes organ recovery, while activation of the non-canonical Wnt pathways exacerbates injury. Moreover, we explore novel therapeutic approaches based on these mechanistic findings, incorporating evidence from animal experiments, current standards, and clinical trials. The objective of this review is to provide deeper insights into the roles of Wnt and its crosstalk signaling pathways in I/R-mediated processes and organ dysfunction, to facilitate the development of innovative therapeutic agents for I/R injury.

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

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

Mechanical thrombectomy combined with intravenous thrombolysis for acute ischemic stroke: a systematic review and meta-analyses

To assess the clinical value of mechanical thrombectomy (MT) combined with intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) by comparing it with the MT alone. In this study, we conducted a comprehensive meta-analysis of both observational and randomized controlled studies (RCTs) to investigate various outcomes. Our search for relevant studies was conducted between January 2011 and June 2022 in four major databases: PubMed, Embase, WOS, and Cochrane Library. We collected data on several outcomes, including functional independence (FI; defined as modified Rankin Scale score of 0 to 2), excellent outcomes (mRS 0-1), successful recanalization (SR), symptomatic intracerebral hemorrhage (sICH), any intracerebral hemorrhage (aICH), and mortality at three months or discharge. The primary efficacy outcome and safety outcome were FI and sICH, respectively, whereas excellent outcomes and SR were considered secondary efficacy outcomes. Additionally, mortality and aICH were analyzed as secondary safety outcomes. We employed the Mantel-Haenszel fixed-effects model for RCTs when I² < 50%, otherwise the random-effects model was utilized. For observational studies and subgroup analyses, we used the random-effects model to minimize potential bias. A total of 55 eligible studies (nine RCTs and 46 observational studies) were included. For RCTs, the MT + IVT group was superior in FI (OR: 1.27, 95% CI: 1.11-1.46), excellent outcomes (OR: 1.21, 95% CI: 1.03-1.43), SR (OR: 1.23, 95% CI: 1.05-1.45), mortality (OR: 0.72, 95% CI: 0.54-0.97) in crude analyses. In adjusted analyses, the MT + IVT group reduced the risk of mortality (OR: 0.65, 95% CI: 0.49-0.88). However, the difference in FI between the MT + IVT group and the MT alone group was not significant (OR: 1.17, 95% CI: 0.99-1.38, Fig. 3a). For observational studies, the results of FI (OR: 1.34, 95% CI: 1.16-1.33), excellent outcomes (OR: 1.30, 95% CI: 1.09-1.54), SR (OR: 1.23, 95% CI: 1.05-1.44), mortality (OR: 0.70, 95% CI: 0.64-0.77) in the MT + IVT group were better. Additionally, the MT + IVT group increased the risk of hemorrhagic transformation (HT) including sICH (OR: 1.16, 95% CI: 1.11-1.21) and aICH (OR: 1.24, 95% CI: 1.05-1.46) in crude analyses. In adjusted analyses, significant better outcomes were seen in the MT + IVT group on FI (OR: 1.36, 95% CI: 1.21-1.52), excellent outcomes (OR: 1.49, 95% CI: 1.26-1.75), and mortality (OR: 0.73, 95% CI: 0.56-0.94). The MT + IVT therapy did improve the prognosis for AIS patients and did not increase the risk of HT compared with MT alone therapy.

Computational analysis of effects of clot length on Acute ischemic stroke recanalization under different cyclic aspiration loading conditions

Acute ischemic stroke, the second leading cause of death worldwide, results from occlusion of a cerebral artery by a blood clot. Application of cyclic aspiration using an aspiration catheter is a current therapy for the removal of lodged clots. In this study, we perform finite element simulations to analyze deformation of long clots, having length to radius ratio of 2-10, which corresponds to clot-length of 2.85-14.25 mm, under peak-to-peak cyclic aspiration pressures of 10-50 mmHg, and frequencies of 0.5, 1, and 2 Hz. Our computational system comprises of a nonlinear viscoelastic solid clot, a hyperelastic artery, and a nonlinear viscoelastic cohesive zone, the latter modeling the clot-artery interface. We observe that clots having length-to-radius ratio approximately greater than two separate from the inner arterial surface somewhere between the axial and distal ends, irrespective of the cyclic aspiration loading conditions. The stress distribution within the clot shows large tensile stresses in the clot interior, indicating the possibility of simultaneous fragmentation of the clot. Thus, this study shows us the various failure mechanisms simultaneously present in the clot during cyclic aspiration. Similarly, the stress distribution within the artery implies a possibility of endothelial damage to the arterial wall near the end where the aspiration pressure is applied. This framework provides a foundation for further investigation to clot fracture and adhesion characterization.

Nomogram-Based Prediction of the Futile Recanalization Risk Among Acute Ischemic Stroke Patients Before and After Endovascular Therapy: A Retrospective Study

Background and Purpose

Futile recanalization (FRC) is common among large artery occlusion (LAO) patients after endovascular therapy (EVT). We developed nomogram models to identify LAO patients at a high risk of FRC pre- and post-EVT to help neurologists select the optimal candidates for EVT.

Methods

From April 2020 to July 2022, EVT and mTICI score ≥2b LAO patients were recruited. Nomogram models was developed by two-step approach for predicting the outcomes of LAO patients. First, the least absolute shrinkage and selection operator (LASSO) regression analysis was to optimize variable selection. Then, a multivariable analysis was to construct an estimation model with significant indicators from the LASSO. The accuracy of the model was verified using receiver operating characteristic (ROC), calibration curve, and decision curve analyses (DCA), along with validation cohort (VC).

Results

Using LASSO, age, sex, hypertension history, baseline NIHSS, ASPECTS and baseline SBP upon admission were identified from the pre-EVT variables. Model 1 (pre-EVT) showed good predictive performance, with an area under the ROC curve (AUC) of 0.815 in the training cohort (TrC) and 0.904 in VC. Under the DCA, the generated nomogram was clinically applicable where risk cut-off was between 15%-85% in the TrC and 5%-100% in the VC. Moreover, age, ASPECTS upon admission, onset duration, puncture-to-recanalization (PTR) duration, and lymphocyte-to-monocyte ratio (LMR) were screened by LASSO. Model 2 (post-EVT) also demonstrated good predictive performance with AUCs of 0.888 and 0.814 for TrC and VC, respectively. Under the DCA, the generated nomogram was clinically applicable if the risk cut-off was between 13-100% in the TrC and 22-85% of VC.

Conclusion

In this study, two nomogram models were generated that showed good discriminative performance, improved calibration, and clinical benefits. These nomograms can potentially accurately predict the risk of FRC in LAO patients pre- and post-EVT and help to select appropriate candidates for EVT.

Internal Carotid Artery Occlusion: Management

PURPOSE OF REVIEW

Acute internal carotid artery occlusion (ICAO) is associated with high rates of morbidity and mortality, whereas chronic ICAO can present insidiously with recurrent strokes. In this review, we discuss the medical and surgical management approaches among patients with acute, subacute, and chronic ICAO.

RECENT FINDINGS

We reviewed the recent literature regarding clinical presentation of acute and chronic cases of ICAO, and discuss the current data, accepted guidelines, and prospects. Surgical, endovascular, or a combination (hybrid) revascularization has been shown to be effective in recanalization with improved functional outcomes in patients with ICAO in comparison to systemic thrombolysis or medical therapy alone. Future prospective or randomized clinical trials are warranted to elucidate the procedural superiority for revascularization of patients with ICAO.

The End of Tissue-Type Plasminogen Activator's Reign?

Mechanical thrombectomy is a highly effective treatment for acute ischemic stroke caused by large-vessel occlusion in the anterior cerebral circulation, significantly increasing the likelihood of recovery to functional independence. Until recently, whether intravenous thrombolysis before mechanical thrombectomy provided additional benefits to patients with acute ischemic stroke-large-vessel occlusion remained unclear. Given that reperfusion is a key factor for clinical outcome in patients with acute ischemic stroke-large-vessel occlusion and the efficacy of both intravenous thrombolysis and mechanical thrombectomy is time-dependent, achieving complete reperfusion with a single pass should be the primary angiographic goal. However, it remains undetermined whether extending the procedure with additional endovascular attempts or local lytics administration safely leads to higher reperfusion grades and whether there are significant public health and cost implications. Here, we outline the current state of knowledge and research avenues that remain to be explored regarding the consistent therapeutic benefit of intravenous thrombolysis in anterior circulation strokes and the potential place of adjunctive intra-arterial lytics administration, including alternative thrombolytic agent place.

Does prior administration of rtPA influence acute ischemic stroke clot composition? Findings from the analysis of clots retrieved with mechanical thrombectomy from the RESTORE registry

BACKGROUND AND PURPOSE

There is still much debate whether bridging-therapy [intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT)] might be beneficial compared to MT alone. We investigated the effect of IVT on size and histological composition of the clots retrieved from patients undergoing bridging-therapy or MT alone.

METHODS

We collected mechanically extracted thrombi from 1000 acute ischemic stroke (AIS) patients included in RESTORE registry. Patients were grouped according to the administration (or not) of IVT before thrombectomy. Gross photos of each clot were taken and Extracted Clot Area (ECA) was measured using ImageJ software. Martius Scarlett Blue stain was used to characterize the main histological clot components [red blood cells (RBCs), fibrin (FIB), platelets/other (PTL)] and Orbit Image Analysis was used for quantification. Additionally, we calculated the area of each main component by multiplying the component percent by ECA. Chi-squared and Kruskal-Wallis tests were used for statistical analysis.

RESULTS

451 patients (45%) were treated with bridging-therapy while 549 (55%) underwent MT alone. When considering only percent histological composition, we did not find any difference in RBC% (P = 0.895), FIB% (P = 0.458) and PTL% (P = 0.905). However, bridging-therapy clots were significantly smaller than MT-alone clots [32.7 (14.8-64.9) versus 36.8 (20.1-79.8) mm², N = 1000, H1 = 7.679, P = 0.006*]. A further analysis expressing components per clot area showed that clots retrieved from bridging-therapy cases contained less RBCs [13.25 (4.29-32.06) versus 14.97 (4.93-39.80) mm², H1 = 3.637, P = 0.056] and significantly less fibrin [9.10 (4.62-17.98) versus 10.54 (5.57-22.48) mm², H1 = 7.920, P = 0.005*] and platelets/other [5.04 (2.26-11.32) versus 6.54 (2.94-13.79) mm², H1 = 9.380, P = 0.002*] than MT-alone clots.

CONCLUSIONS

Our results suggest that previous IVT administration significantly reduces thrombus size, proportionally releasing all the main histological components.

Thrombectomy Versus Combined Thrombolysis and Thrombectomy in Patients With Acute Stroke: A Matched-Control Study

[Figure: see text].

In-Hospital Intravenous Thrombolysis Offers No Benefit in Mechanical Thrombectomy in Optimized Tertiary Stroke Center Setting

Purpose

Mechanical thrombectomy (MT) is the first-line treatment in acute stroke patients presenting with large vessel occlusion (LVO). The efficacy of intravenous thrombolysis (IVT) prior to MT is being contested. The objective of this study was to evaluate the efficacy of MT without IVT in patients with no contraindications to IVT presenting directly to a tertiary stroke center with acute anterior circulation LVO.

Materials and Methods

We collected the data of 106 acute stroke patients who underwent MT in a single high-volume stroke center. Patients with anterior circulation LVO eligible for IVT and directly admitted to our institution who subsequently underwent MT were included. We recorded baseline clinical, laboratory, procedural, and imaging variables and technical, imaging, and clinical outcomes. The effect of intravenous thrombolysis on 3-month clinical outcome (mRS) was analyzed with univariate tests and binary and ordinal logistic regression analysis.

Results

Fifty-eight out of the 106 patients received IVT + MT. These patients had 2.6-fold higher odds of poorer clinical outcome in mRS shift analysis (p = 0.01) compared to MT-only patients who had excellent 3-month clinical outcome (mRS 0–1) three times more often (p = 0.009). There were no significant differences between the groups in process times, mTICI, or number of hemorrhagic complications. A trend of less distal embolization and higher number of device passes was observed among the MT-only patients.

Conclusions

MT without prior IVT was associated with an improved overall three-month clinical outcome in acute anterior circulation LVO patients.

Supplementary Information

The online version of this article (10.1007/s00270-020-02727-8) contains supplementary material, which is available to authorized users.

Differential effect of mechanical thrombectomy and intravenous thrombolysis in atrial fibrillation associated stroke

BACKGROUND

Atrial fibrillation (AF) associated ischemic stroke has worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications after intravenous thrombolysis (IVT). Limited data exist about the effect of AF on procedural and clinical outcomes after mechanical thrombectomy (MT).

OBJECTIVE

To determine whether recanalization efficacy, procedural speed, and clinical outcomes differ in AF associated stroke treated with MT.

METHODS

We performed a retrospective cohort study of the Stroke Thrombectomy and Aneurysm Registry (STAR) from January 2015 to December 2018 and identified 4169 patients who underwent MT for an anterior circulation stroke, 1517 (36.4 %) of whom had comorbid AF. Prospectively defined baseline characteristics, procedural outcomes, and clinical outcomes were reported and compared.

RESULTS

AF predicted faster procedural times, fewer passes, and higher rates of first pass success on multivariate analysis (p<0.01). AF had no effect on intracranial hemorrhage (aOR 0.69, 95% CI 0.43 to 1.12) or 90-day functional outcomes (aOR 1.17, 95% CI 0.91 to 1.50) after MT, although patients with AF were less likely to receive IVT (46% vs 54%, p<0.0001).

CONCLUSIONS

In patients treated with MT, comorbid AF is associated with faster procedural time, fewer passes, and increased rates of first pass success without increased risk of intracranial hemorrhage or worse functional outcomes. These results are in contrast to the increased hemorrhage rates and worse functional outcomes observed in AF associated stroke treated with supportive care and or IVT. These data suggest that MT negates the AF penalty in ischemic stroke.

Bridging Thrombolysis Achieved Better Outcomes Than Direct Thrombectomy After Large Vessel Occlusion: An Updated Meta-Analysis

The utility and necessity of pretreatment with intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remains an issue of strong debate. This study aims to compare the outcomes of bridging thrombolysis (BT, IVT+MT) with direct MT (d-MT) after large vessel ischemic stroke based on the most up-to-date evidence. MEDLINE, EMBASE, Scopus, and the Cochrane Library from January 2017 to June 2020 were searched for studies that directly compared the outcomes of the 2 strategies. Methodological quality was assessed using the Quality in Prognostic Studies tool. Combined estimates of odds ratios (ORs) of BT versus d-MT were derived. Multiple subgroup analyses were performed, especially for IVT-eligible patients. Thirty studies involving 7191 patients in the BT group and 4891 patients in the d-MT group were included. Methodological quality was generally high. Compared with patients in the d-MT group, patients in the BT group showed significantly better functional independence (modified Rankin Scale score 0-2) at 90 days (OR=1.43 [95% CI, 1.28-1.61]), had lower mortality at 90 days (OR=0.67 [95% CI, 0.60-0.75]), and achieved higher successful recanalization (modified Thrombolysis in Cerebral Ischemia score 2b-3) rate (OR=1.23 [95% CI, 1.07-1.42]). No significant difference was detected in the occurrence of symptomatic intracranial hemorrhage between 2 groups (OR=1.01 [95% CI, 0.86-1.19]). Subgroup analysis showed that functional independence frequency remained significantly higher in BT group regardless of IVT eligibility or study design. Compared with d-MT, bridging with IVT led to better clinical outcomes, lower mortality at 90 days, and higher successful recanalization rates, without increasing the risk of near-term hemorrhagic complications. The benefits of BT based on this most recent literature evidence support the current guidelines of using BT.

Impact of off-hour endovascular therapy on outcomes for acute ischemic stroke: insights from STAR

BACKGROUND

The off-hour effect has been observed in the medical care of acute ischemic stroke. However, it remains unclear if time of arrival affects revascularization rates and outcomes after endovascular therapy (EVT) for emergent large vessel occlusion (ELVO). We aimed to investigate the clinical outcomes of EVT between on-hour and off-hour admissions.

METHODS

Patients who underwent EVT for ELVO from January 2013 to June 2019 from the STAR Registry were included. Patients were grouped based on time of groin puncture: on-hour period (Monday through Friday, 7:00 am-4:59 pm) and off-hour period (overnight 5:00pm-6:59am and the weekends). Primary outcome was final modified Rankin Scale (mRS) at 90 days on mRS-shift analysis.

RESULTS

A total of 1919 patients were included in the study from six centers. The majority of patients (1169, 60.9%) of patients presented during the off-hour period. The mean age was 68.1 years and 50.5% were women. Successful reperfusion, as defined by a Thrombolysis In Cerebral Infarction (TICI) score of ≥2B, was achieved in 88.8% in the on-hour group and 88.0% in the off-hour group. Good clinical outcome (mRS 0-2) was obtained in 34.4% of off-hour patients and 37.7% of on-hour patients. On multivariable ordinal logistic regression analysis, time of presentation was not associated with worsened outcome (OR 1.150; 95% CI 0.96 to 1.37; P=0.122). Age, admission National Institutes of Health Stroke Scale (NIHSS), baseline mRS, and final TICI score were significantly associated with worse outcomes.

CONCLUSION

There is no statistical difference in functional outcome in acute ischemic stroke patients who underwent EVT during on-hours versus off-hours.

Risk analysis of post-procedural intracranial hemorrhage based on STAY ALIVE Acute Stroke Registry

BACKGROUND

Intracranial hemorrhages (ICH) are classified as symptomatic or asymptomatic according to the presence of clinical deterioration. Here, we aimed to find predictive factors of symptomatic intracranial bleeding in a registry-based stroke research.

METHODS

Data of consecutive patients with acute ischemic stroke (AIS) were extracted from the prospective STAY ALIVE stroke registry. Analysis of the total population and treatment sugroups such as endovascular thrombectomy (EVT), intravenous thrombolysis (IVT), or their combination (IVT+EVT) were also done. Outcome measures were ICH, 30- and 90-day clinical outcome based on the modified Rankin Scale (mRS:0-2 as favorable outcome). The hemorrhage was captured by a non-enhanced CT of the skull within 24 h after procedure.

RESULTS

A total of 355 patients (mean age: 68±11; female N=177 (49.9%); EVT n=131 (36.9%); IVT n=157 (44.2%); IVT+EVT n=67 (18.9%) were included in the analysis. The total number of ICH was 47 (13%), symptomatic (sICH) 12 (3.4%) and asymptomatic (aICH) 35 (9.9%) in the whole population. NIHSS ≥15.5 at 24 post stroke hours predicted sICH with a sensitivity of 100% and a specificity of 92% (p<0.001). Furthermore, lower age, good collateral circulation on initial CT angiography and lower NIHSS score measured at 24 h independently associated with a favorable 90-day outcome, whereas baseline NIHSS and ASPECT score were not.

CONCLUSION

Although partial recanalization, ASPECT< 6, and poor collaterals were significantly associated with sICH, the only independent predictor was NIHSS ≥15.5 at 24 post stroke hours. This suggests a careful evaluation of patients with worsening NIHSS despite an adequate therapy.

Intravenous thrombolysis for large vessel or distal occlusions presenting with mild stroke severity

BACKGROUND AND PURPOSE

We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points.

METHODS

The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding.

RESULTS

We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy.

CONCLUSIONS

Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.

Outcome of patients with large vessel occlusion stroke after first admission in telestroke spoke versus comprehensive stroke center

Introduction

While telestroke allows early intravenous thrombolysis (IVT) for ischemic strokes in spoke centers, mechanical thrombectomy (MT) for large vessel occlusion (LVO) is mainly performed at comprehensive stroke centers (CSCs). We aimed to compare 3 month outcome in patients with LVO after admission to a spoke center using telestroke compared with first CSC admission in our large regional stroke network, irrespective of final treatment decision.

Methods

All consecutive LVO patients who were admitted to one of six spoke centers or to the regional CSC within 6 hours of symptom onset were prospectively included from September 1, 2015 to August 31, 2017. All patients admitted to spoke centers were assessed on site with cerebral and vessel imaging. Primary outcome was 3 month favorable outcome (modified Rankin Scale score of 0–2).

Results

Distances between spoke centers and CSC ranged from 36 to 77 miles. Among 207 included patients, 132 (63.8%) were first admitted to CSCs and 75 (36.2%) to spoke centers. IVT was administered more in spoke centers (81.3% vs 53.8%, p<0.0001) while MT was performed less (26.7% vs 49.2%, p=0.001) and with a longer time from onset (303 vs 200 min, p<0.0001). No difference was found in 3 month favorable outcome between spoke centers compared with CSCs (32.0% and 35.1%, respectively; OR=0.68; 95% CI 0.42 to 1.10; p=0.12).

Conclusions

Despite different distribution of reperfusion therapies for LVO patients managed by telemedicine, we could not demonstrate a difference in functional outcome according to admission location in a large area with long distances between centers.