Clinical deterioration following improvement in the NINDS rt-PA Stroke Trial

Outcomes of antiplatelet therapy before endovascular treatment of acute large vessel occlusion: Data from the ANGEL-ACT registry

OBJECTIVES

To investigate whether single or dual antiplatelet therapy (SAPT or DAPT) within 24 hours before endovascular treatment (EVT) could improve the clinical outcomes of patients with large vessel occlusion (LVO).

METHODS

Patients from the ANGEL-ACT registry were divided into antiplatelet therapy (APT) and non-APT groups. The APT group was divided into SAPT and DAPT groups. Outcome measurement included 90-day modified Rankin Scale (mRS) distribution, change in the NIHSS at 7 days or discharge, number of passes, modified first pass effect (mFPE), symptomatic intracranial hemorrhage (SICH), and mortality within 90 days. To compare the outcomes, we performed multivariable analyses by adjusting for the propensity score calculated by the logistic regression model.

RESULTS

Of 1611 patients, 1349 were in the non-APT group, while 262 (16.3 %) were in the APT group (122 [46.6 %] received SAPT, 140 [53.4 %] received DAPT). APT, SAPT or DAPT were not associated with a shift to better outcomes (non-APT vs. APT, 3[0-5] vs. 3[0-5], common odds ratio [OR], 1.04, 95 %confidence interval [CI]:0.82-1.34, P = 0.734). DAPT was associated with mFPE (OR,2.05, 95 %CI:1.39-3.01, P<0.001), more NIHSS reduction at 7 days or discharge (β, -2.13, 95 %CI: -4.02--0.24, P = 0.028), lower number of passes (β, -0.40, 95 %CI: -0.68--0.12, P=0.006), and shorter procedure duration (β, -12.4, 95 %CI: -23.74--1.05, P = 0.032) without increasing odds of successful recanalization, PH within 24 hours and mortality with 90 days .

CONCLUSIONS

APT before MT for AIS due to LVO does not affect clinical outcome in 90 days despite a tendency to reduce MT procedure time and number of passes. APT before MT in LVO does not increase SICH or mortality rates.

Analysis of Clinical Characteristics and Influencing Factors of Early Neurological Deterioration in Patients With Mild Stroke by Intravenous Alteplase Therapy

OBJECTIVES

Thrombolysis treatment for patients with mild stroke is controversial. The aim of our study was to investigate the clinical characteristics and influencing factors of early neurological deterioration (END) in this group of patients.

METHODS

A retrospective analysis was performed on ischemic stroke patients with intravenous thrombolysis (IVT) in Wenzhou Central Hospital. Subgroup analyses were performed for the mild stroke group and nonmild stroke group, END group, and non-early neurological deterioration group in mild stroke patients, respectively.

RESULTS

A total of 498 patients were included in this study. Compared with the control group, the mild stroke group was younger age, less atrial fibrillation, previous history of stroke and less use of antithrombotic drugs, more dyslipidemia, smoking, and drinking. Small artery occlusion type was more common in mild stroke, cardioembolism and stroke of undetermined etiology type were less. In the mild stroke group, the symptomatic intracerebral hemorrhage (sICH) rate was 2.54%, and the END rate was 16.1%. Predictors of END included systolic blood pressure, blood glucose, cardioembolism subtype, sICH, and large vessel occlusion. In END patients, the sICH rate was 10.53%, and 84.21% of cases started to worsen within 12 hours after IVT. There was no statistically significant difference in the time to exacerbation among different subtypes.

CONCLUSIONS

The occurrence of mild stroke in young patients was largely related to unhealthy lifestyles. The incidence of END in mild stroke IVT patients was low, with most occurring within 12 hours of IVT. There were many risk factors for END: large vessel occlusion and hyperglycemia were independent risk factors for END after IVT. sICH was an important but rare risk factor for END.

Risk factors of unexplained early neurological deterioration after treatment for ischemic stroke due to large vessel occlusion: a post hoc analysis of the HERMES study

BACKGROUND

Early neurological deterioration (END) after endovascular treatment (EVT) in patients with anterior circulation acute ischemic stroke (AIS) is associated with poor outcome. END may remain unexplained by parenchymal hemorrhage (UnEND). We aim to analyze the risk factors of UnEND in the medical management (MM) and EVT arms of the HERMES study.

METHODS

We conducted a post-hoc analysis of anterior AIS patients who underwent EVT for proximal anterior occlusions. Risk factors of UnEND, defined as a worsening of ≥4 points between baseline National Institutes of Health Stroke Scale (NIHSS) and NIHSS at 24 hours without hemorrhage, were compared between both arms using mixed logistic regression models adjusted for baseline characteristics. An interaction analysis between the EVT and MM arms for risk factors of UnEND was conducted.

RESULTS

Among 1723 patients assessable for UnEND, 160 patients experienced an UnEND (9.3%), including 9.1% (78/854) in the EVT arm and 9.4% (82/869) in the MM arm. There was no significant difference in the incidence of UnEND between the two study arms. In the EVT population, independent risk factors of UnEND were lower baseline NIHSS, higher baseline glucose, and lower collateral grade. In the MM population, the only independent predictor of UnEND was higher baseline glucose. However, we did not demonstrate an interaction between EVT and MM for baseline factors as risk factors of UnEND. UnEND was, similarly in both treatment groups, a significant predictor of unfavorable outcome in both the EVT (p<0.001) and MM (p<0.001) arms.

CONCLUSIONS

UnEND is not an uncommon event, with a similar rate which ever treatment arm is considered. In the clinical scenario of AIS due to large vessel occlusion, no patient-related factor seems to increase the risk for UnEND when treated by EVT compared with MM.

Prospective pilot study of tirofiban in progressive stroke after intravenous thrombolysis

Background

Intravenous thrombolysis (IVT) is a standard procedure for the treatment of patients with acute ischemic stroke (AIS). Improving the therapeutic efficacy of IVT is an important task for neurologists. The aim of this study was to evaluate the efficacy and safety of early low-dose tirofiban treatment in AIS patients with early neurological deterioration (END) after IVT.

Methods

In this prospective and randomized pilot study, 73 AIS patients with END were recruited from a local hospital in China. Of these, 14 patients were treated with regular antiplatelet agents (aspirin plus clopidogrel) and 59 patients were treated with tirofiban within 24 h of IVT, followed by regular antiplatelet therapy. Neurological deficits and functional recovery were assessed with NIHSS and modified Rankin Scale (mRS) at 7 and 90 days. During the 90-day follow-up period, both hemorrhagic (e.g., intracerebral hemorrhage) and non-hemorrhagic (e.g., pneumonia) events were recorded.

Results

Treatment with tirofiban compared with regular antiplatelet therapy: (1) improved functional recovery of AIS patients to mRS (≤2) at both 7 and 90 days (odds ratios [ORs], 1.37 and 1.64; 95% confidence interval [CI], 1.16–1.61 and 1.26–2.12; P = 0.008 and < 0.001, respectively), and (2) reduced NIHSS scores from 11.14 ± 2.38 to 5.95 ± 3.48 at day 7 (P < 0.001) and from 8.14 ± 2.74 to 4.08 ± 3.50 at day 90 (P < 0.001). Tirofiban treatment did not increase the risk of hemorrhagic complications. Multivariate regression analysis showed that tirofiban treatment independently predicted a favorable functional outcome (P ≤ 0.001).

Conclusion

Early treatment with low-dose tirofiban in AIS patients with neurologic deterioration after IVT potentially improved functional recovery and attenuated neurologic deficits as early as 7 days and did not increase the risk of various hemorrhagic complications. However, the therapeutic efficacy of tirofiban treatment in END patients needs to be determined by future randomized clinical trials with a large study population.

Clinical trial registration

http://www.chictr.org.cn/, Identifier ChiCTR2200058513.

Predictors of early neurologic deterioration (END) following stroke thrombectomy

BACKGROUND

Early neurologic deterioration (END) following ischemic stroke is a serious event and is associated with poor outcomes. However, the incidence and predictors of END after stroke thrombectomy for emergent large vessel occlusion are largely unknown.

METHODS

The baseline characteristics of patients enrolled in the COMPASS trial (NCT02466893) were analyzed. The primary outcome was worsening of ≥4 National Institutes of Health Stroke Scale (NIHSS) points 24 hours post thrombectomy (4+ END₂₄) and the secondary outcome was deterioration of ≥2 points (2+ END₂₄).

RESULTS

Among 270 patients, 27 (10%) developed 4+ END₂₄ and 42 (16%) had 2+ END₂₄. Those with 4+ END₂₄ were older (76.4±12.9 vs 70.9±12.9 years; p=0.04), had a higher prevalence of hypertension (96% vs 69%; p=0.003), diabetes (41% vs 27%; p=0.13) and higher pretreatment systolic blood pressure (SBP) (170.4±32.6 vs 157.6±28.1 mmHg; p=0.03). More 4+ END₂₄ patients had failed reperfusion: Thrombolysis in Cerebral Infarction ≤2a (26% vs 8%; p=0.003). In unadjusted analysis, older patients and those with hypertension, diabetes, elevated SBP and failed reperfusion had higher odds of 4+ END₂₄. In adjusted analysis, age increase by 5 years led to an increase in 4+ END₂₄ of 28%, diabetes increased odds of 2.6 and failed reperfusion increased odds of 4.5. In the multivariable analysis for the secondary outcome, age (OR 1.33; 95% CI 1.109 to 1.593), diabetes (OR 2.7; 95% CI 1.247 to 5.764) and failed reperfusion (OR 7.2; 95% CI 0.055 to 0.349) were also significant predictors of 2+ END₂₄.

CONCLUSIONS

Older patients with acute ischemic stroke who have a history of diabetes or hypertension, with elevated pretreatment SBP and failed reperfusion are at a higher risk of END following stroke thrombectomy for emergent large vessel occlusion.

Rt-PA thrombolytic therapy in patients with acute posterior circulation stroke: A retrospective study

At present, recombinant tissue-type plasminogen activator (rt-PA) thrombolytic therapy is widely used in patients with acute ischemic stroke within 4.5 h following stroke onset. However, the efficacy of intravenous alteplase thrombolytic therapy for posterior circulation stroke (PCS) has been rarely described. The present study aimed to predict the outcome of patients with PCS following rt-PA thrombolytic therapy in a more efficient manner. Data were collected from patients who had suffered from posterior circulation ischemic stroke, who had been treated with rt-PA over a period of 4 years (2016-2020), and had been treated at a stroke center. All patients were treated with alteplase at a standard dose of 0.9 mg/kg. According to the onset to needle time (ONT), these patients were divided into the 0-3 and 3-4.5 h groups, and the National Institutes of Health Stroke Scale (NIHSS) score was compared before thrombolysis and at 24 h after thrombolysis. Subsequently, the patients with acute PCS whose ONT was ≤3 h were divided into the NIHSS score >3 points and NIHSS score ≤3 points groups, and the NIHSS score improvement rate was compared 24 h later. A total of 989 patients were included in the study; there were 783 patients with acute anterior circulation stroke (ACS) and 203 patients with acute PCS (of note, 2 patients had negative results from brain magnetic resonance imaging); 63 patients were treated with urokinase (UK) thrombolysis and 140 patients were treated with alteplase intravenous thrombolysis. The 140 patients that received alteplase thrombolytic therapy were divided into two groups, namely the ≤3 h group and 3-4.5 h group, which, on the basis of the ONT, no significant differences were found between the two the groups according to the NIHSS score before thrombolysis (P>0.05). The NHISS scores in the ≤3 h group were significantly lower than those in the 3-4.5 h group following thrombolysis therapy, and the differences between the two groups were statistically significant (P<0.05); the patients with acute PCS treated with rt-PA in the ≤3 h group were divided into the NIHSS score ≤3 points group and the NIHSS score >3 points group. In this ≤3 h group, the average NIHSS score improvement rate following rt-PA thrombolysis was 0.535 (53.5%) in the NIHSS score ≤3 points group and that in the NIHSS score >3 points group was 0.336 (33.6%); the difference between the two groups was statistically significant (P<0.05). The patients treated with intravenous alteplase thrombolysis within 3 h following stroke onset benefited more than those treated with thrombolysis therapy within 3 to 4.5 h after stroke onset. On the whole, the present study demonstrates that the patients with mild stroke (NIHSS score ≤3 points) who were treated at an earlier stage (received alteplase thrombolysis therapy within 3 h after stroke onset) benefited to a greater extent from the therapy.

Evaluation of Transient Ischemic Attack and Minor Stroke: A Rapid Outpatient Model for the COVID-19 Pandemic and Beyond

The grim circumstances of the COVID-19 pandemic have highlighted the need to refine and adapt stroke systems of care. Patients' care-seeking behaviors have changed due to perceived risks of in-hospital treatment during the pandemic. In response to these challenges, we optimized a recently implemented, novel outpatient approach for the evaluation and management of minor stroke and transient ischemic attack, entitled RESCUE-TIA. This modified approach incorporated telemedicine visits and remote testing, and proved valuable during the pandemic. In this review article, we provide the evidence-based rationale for our approach, describe its operationalization, and provide data from our initial experience.

Safety and Efficacy of Endovascular Treatment for Progressive Stroke in Patients With Acute Basilar Artery Occlusion

Background and Purpose: It is unknown the benefit of endovascular therapy (EVT) for progressive stroke in patients with basilar artery occlusion (BAO). The aim of this study was to compare the efficacy and safety of EVT with standard medical therapy (SMT) in a population of BAO patients with progressive stroke.

Methods: The EVT for Acute Basilar Artery Occlusion Study (BASILAR) is a national prospective registry of consecutive patients with acute BAO within 24 h of symptom onset. According to the applied therapy, all patients were divided into SMT and EVT groups. Subsequently, the EVT group was divided into early (≤6 h) and late groups (>6 h) according to the time window. The efficacy outcome was favorable functional outcomes (modified Rankin Scale score ≤ 3) at 90 days. The safety outcomes included mortality within 90 days and symptomatic intracerebral hemorrhage (sICH) after EVT.

Results: The EVT cohort presented more frequently with a favorable functional outcome (adjusted odds ratio, 5.49; 95% confidence interval, 2.06–14.61, p = 0.01) and with a decreased mortality (adjusted odds ratio, 0.3; 95% confidence interval, 0.17–0.54, p < 0.001). What's more, EVT still safe (P = 0.584, P = 0.492, respectively) and effective (P = 0.05) in patients with progressive stroke when the treatment time window exceeds 6 h.

Conclusions: EVT was more effective and safer than SMT for progressive stroke in patients with BAO. Besides, EVT remains safe and effective in patients with progressive stroke when the treatment time window exceeds 6 h. Predictors of desirable outcome in progressive stroke patients undergoing EVT included lower baseline NIHSS score, higher baseline pc-ASPECTs, successful recanalization and shorter puncture to recanalization time.

Caught in Action - Evolving Emergent Large Vessel Occlusion and Collateral Failure During Alteplase Infusion for Acute Ischemic Stroke

BACKGROUND

Published reports of acute deterioration during alteplase infusion for acute ischemic stroke due to development of partial to complete large vessel occlusion and collateral failure are sparce.

MATERIALS AND METHODS

We describe an 84-year-old patient with a fluctuating clinical course due to evolving emergent large vessel occlusion of right M1 segment of the middle cerebral artery and collateral failure during alteplase infusion. Potential mechanisms of acute deterioration within 24 h after thrombolysis are discussed.

RESULTS

Urgent mechanical thrombectomy was performed with resultant partial recanalization and small volume residual infarcts at 72 h magnetic resonance imaging of brain.

CONCLUSIONS

Progression from partial to complete occlusion may occur within minutes, even during administration of intravenous thrombolytics in hyper-acute stroke. In patients who deteriorate within 24 h of stroke onset, non-contrast CT of brain, followed by CT perfusion and angiography, is the imaging protocol of choice in the mechanical thrombectomy era.

Fifty Years of Acute Ischemic Stroke Treatment: A Personal History

BACKGROUND

It has been 50 years since the first explorations of the physiology of cerebral ischemia by measuring cerebral blood flow (CBF), and 25 years since the approval of tissue plasminogen activator for treating acute ischemic stroke. My personal career began and matured during those eras. Here, I provide my perspective on the evolution of acute stroke research and treatment from 1971 to the present, with some in-depth discussion of the National Institutes of Neurologic Disease and Stroke (NINDS) tissue-type plasminogen activator (tPA) stroke trial and development of mobile stroke units.

SUMMARY

Studies of CBF and metabolism in acute stroke patients revealed graded tissue injury that was dependent on the duration of ischemia. Subsequent animal research unraveled the biochemical cascade of events occurring at the cellular level after cerebral ischemia. After a decade of failed translation, the development of a relatively safe thrombolytic allowed us to achieve reperfusion and apply the lessons from earlier research to achieve positive clinical results. The successful conduct of the NINDS tPA stroke study coupled with positive outcomes from companion tPA studies around the world created the specialty of vascular neurology. This was followed by an avalanche of research in imaging, a focus on enhancing reperfusion through thrombectomy, and improving delivery of faster treatment culminating in mobile stroke units. Key Messages: The last half century has seen the birth and evolution of successful acute stroke treatment. More research is needed in developing new drugs and catheters to build on the advances we have already made with reperfusion and also in evolving our systems of care to get more patients treated more quickly in the prehospital setting. The history of stroke treatment over the last 50 years exemplifies that medical "science" is an evolving discipline worth an entire career's dedication. What was impossible 50 years ago is today's standard of care, what we claim as dogma today will be laughed at a decade from now, and what appears currently impossible will be tomorrow's realities.

Frequency and Prognostic Significance of Clinical Fluctuations Before Hospital Arrival in Stroke

BACKGROUND AND PURPOSE

Clinical fluctuations in ischemic stroke symptoms are common, but fluctuations before hospital arrival have not been previously characterized.

METHODS

A standardized qualitative assessment of fluctuations before hospital arrival was obtained in an observational study that enrolled patients with mild ischemic stroke symptoms (National Institutes of Health Stroke Scale [NIHSS] score of 0-5) present on arrival to hospital within 4.5 hours of onset, in a subset of 100 hospitals participating in the Get With The Guidelines-Stroke quality improvement program. The number of fluctuations, direction, and the overall improvement or worsening was recorded based on reports from the patient, family, or paramedics. Baseline NIHSS on arrival and at 72 hours (or discharge if before) and final diagnosis and stroke subtype were collected. Outcomes at 90 days included the modified Rankin Scale, Barthel Index, Stroke Impact Scale 16, and European Quality of Life. Prehospital fluctuations were examined in relation to hospital NIHSS change (admission to 72 hours or discharge) and 90-day outcomes.

RESULTS

Among 1588 participants, prehospital fluctuations, consisting of improvement, worsening, or both were observed in 35.5%: 25.1% improved once, 5.3% worsened once, and 5.1% had more than 1 fluctuation. Those who improved were less likely and those who worsened were more likely to receive alteplase. Those who improved before hospital arrival had lower change in the hospital NIHSS than those who did not fluctuate. Better adjusted 90-day outcomes were noted in those with prehospital improvement compared to those without any fluctuations.

CONCLUSIONS

Fluctuations in neurological symptoms and signs are common in the prehospital setting. Prehospital improvement was associated with better 90-day outcomes, controlling for admission NIHSS and alteplase treatment.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02072681.

Causes, Predictors, and Timing of Early Neurological Deterioration and Symptomatic Intracranial Hemorrhage After Administration of IV tPA

Background

Acute ischemic stroke (AIS) is a major contributor toward healthcare-associated costs and services. Symptomatic intracranial hemorrhage (sICH) and early neurologic decline (END), defined as a National Health Institute Stroke Scale score decline of ≥ 4 within 24 h (with or without sICH), remain major concerns when administering intravenous tissue plasminogen activator (IV tPA) despite improved functional neurologic outcomes with its use. Given these risks, current guidelines recommend comprehensive stroke care (most often in an intensive care unit setting) for 24 h posttreatment. However, a number of patients may remain stable after IV tPA and thus not require such intensive resources. We sought to determine causes of END, along with timing and predictors of both sICH and END, to identify patients at lower risk of neurological deterioration and those suitable for earlier transition to a lower level of care.

Methods

This present study analyzed patients with AIS that presented within 4.5 h of being last seen well and received IV tPA. Baseline demographic, clinical, and radiographic findings were collected. Outcomes included END from any cause, parenchymal hemorrhage (PH1 or PH2), sICH, and mortality at 90 days.

Results

A total of 1238 patients with AIS without acute treatment of large vessel occlusion received IV tPA. 9.4% (116) had presence of any degree of ICH on noncontrast computed tomography head and 7.4% (91) experienced associated END. 2.7% (33) of patients experienced sICH, while 6.7% (83) experienced asymptomatic ICH. Of the patients with END, 63.7% did not have ICH. Predictive factors at presentation for END included an older age (72.6 ± 16.1 vs. 69.1 ± 14.8, p = 0.03), history of tobacco use (odds ratio [OR] 2.1 [1.1–4.3], p = 0.04), and hyperlipidemia (OR 1.7 [1.1–2.8], p = 0.02), along with the presence of an untreated large vessel occlusion (OR 2.1 [1.4–3.1], p = 0.02). Most END occurred within a mean time of 242 ± 251 min (4 ± 4 h). Because of the small proportion of patients suffering from sICH (33), predictors could not be determined; however, for patients with any ICH, predictive factors included an older age (74.6 ± 12.4 vs. 68.8 ± 15.1, p = 0.001), higher baseline National Health Institute Stroke Scale score (14.6 ± 7.3 vs. 10.8 ± 7.9, p = 0.002), and higher baseline glucose levels (155.1 ± 87.5 vs. 140.4 ± 70.5, p = 0.04).

Conclusions

In this study, only a small proportion suffered from either sICH and/or END, typically within 12 h of tPA administration. These findings may support earlier deescalation of higher acuity monitoring in clinically stable post-IV tPA patients without large vessel occlusion.

Clinical imaging factors of excellent outcome after thrombolysis in large-vessel stroke: a THRACE subgroup analysis

Background

For patients with stroke with large-vessel occlusion (LVO), study of factors predicting response to intravenous thrombolysis (IVT) would allow identifying subgroups with high expected gain, and those for whom it could be considered as futile, and even detrimental. From patients included in the Mechanical Thrombectomy After Intravenous Alteplase vs Alteplase Alone After Stroke trial, we investigated clinical-imaging factors associated with optimal response to IVT.

Methods

We included patients receiving IVT alone. Excellent outcome was defined by a 3-month modified Rankin Scale (mRS) score ≤1. Clinical-imaging predictors were assessed on multivariate analysis after multiple imputations. The predictive performance of the model was assessed with the C-statistic.

Results

Among 247 patients with LVO treated with IVT alone, 77 (31%) showed 3-month mRS ≤1. Predictors of 3-month mRS ≤1 were no medical history of hypertension (OR 2.43; 95% CI 1.74 to 3.38; p=0.007); no current smoking (OR 2.76; 95% CI 1.79 to 4.26; p=0.02); onset-to-IVT time (OR 0.47 per hour increase; 95% CI 0.23 to 0.78; p=0.003); diffusion-weighted imaging (DWI) volume (OR 0.78 per 10 mL increase; 95% CI 0.68 to 0.89; p=0.0004); presence of susceptibility vessel sign (SVS) (OR 7.89; 95% CI 1.65 to 37.78; p=0.01) and SVS length (OR 0.87 per mm increase; 95% CI 0.80 to 0.94; p=0.001). The prediction models showed a C-statistic=0.79 (95% CI 0.79 to 0.80).

Conclusions

In patients with stroke with anterior-circulation LVO treated with IVT alone, predictors of excellent outcome at 3 months were no medical history of hypertension or current smoking, reduced onset-to-IVT time, small DWI volume, presence of SVS and short SVS length. These predictive factors could help practitioners in decision-making for IVT implementation in reperfusion strategies, all the more for the drip and ship paradigm.

Trial registration number

NCT01062698.

Differences between predictive factors for early neurological deterioration due to hemorrhagic and ischemic insults following intravenous recombinant tissue plasminogen activator

Early neurological deterioration (END) following intravenous recombinant tissue plasminogen activator (rt-PA) treatment is a serious clinical event that can be caused by hemorrhagic or ischemic insult. We investigated the differences in predictive factors for END due to hemorrhagic and END due to ischemic insults. Consecutive patients from four hospitals who received 0.6 mg/kg intravenous rt-PA for acute ischemic stroke were retrospectively recruited. END was defined as a National Institutes of Health Stroke Scale (NIHSS) score ≥ 4 points within 24 h compared with baseline. END was classified into those due to hemorrhagic (END_h) or ischemic (END_i) insult based on computed tomography (CT) or magnetic resonance imaging. Risk factors associated with END_h and END_i were investigated by comparison with non-END cases. A total of 744 patients (452 men, median 75 years old) were included. END was observed in 79 patients (10.6%), including 22 END_h (3.0%) and 57 END_i (7.7%), which occurred within a median of 7 h after treatment. Multivariate analyses showed that higher pretreatment NIHSS score (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.00–1.13) and pretreatment with antiplatelets (OR 2.84, 95% CI 1.08–7.72) were associated with END_h. Extensive early ischemic change (Alberta Stroke Program Early CT Score ≤ 7 on CT or ≤ 6 on diffusion-weighted imaging; OR 2.80, 95% CI 1.36–5.64) and large artery occlusions (OR 3.09, 95% CI 1.53–6.57) were associated with END_i. Distinct factors were predictive for the END subtypes. These findings could help develop preventative measures for END in patients with the identified risk factors.

Safety and efficacy of oral antiplatelet for patients who had acute ischaemic stroke undergoing endovascular therapy

BACKGROUND AND PURPOSE

To investigate the safety and efficacy of oral antiplatelet therapy (APT) for patients who had acute ischaemic stroke (AIS), receiving endovascular therapy (EVT).

METHODS

Patients were divided into non-APT group and APT (single APT or dual APT (DAPT)) group. The safety and efficacy endpoints at 3-month follow-up were symptomatic intracranial haemorrhage (sICH), recanalisation rate, clinical outcome and mortality.

RESULTS

Among 915 patients who had AIS, those in APT group (n=199) showed shorter puncture-to-recanalisation time, lower frequency of intravenous thrombolysis and more use of tirofiban compared with those in non-antiplatelet group (n=716) (p<0.05 for all). Oral APT was found to be associated with superior clinical outcome compared with non-APT (APT (44.2%) versus non-APT (41.1%)), adjusted OR=2.605, 95% CI 1.244 to 5.455, p=0.011). DAPT showed superior clinical outcome compared with non-APT (DAPT (56.5%) versus non-APT (41.1%), adjusted OR=5.405, 95% CI 1.614 to 18.102, p=0.006) and lower risk of mortality at 3-month follow-up (DAPT (4.8%) versus non-DAPT (17.7%), adjusted OR=0.008, 95% CI 0.000 to 0.441, p=0.019). There was no significant difference in sICH between the two groups.

CONCLUSIONS

Oral APT prior to undergoing EVT is safe and may accompany with superior clinical outcomes. DAPT may associate with superior clinical outcomes and lower risk of mortality.

Prior antiplatelet therapy in patients undergoing endovascular treatment for acute ischemic stroke: Results from the MR CLEAN Registry

Background

Antiplatelet therapy may increase the risk of symptomatic intracranial hemorrhage after endovascular treatment for ischemic stroke but may also have a beneficial effect on functional outcome. The aim of this study is to compare safety and efficacy outcomes after endovascular treatment in patients with and without prior antiplatelet therapy.

Methods

We analyzed patients registered in the MR CLEAN Registry between March 2014 and November 2017, for whom data on antiplatelet therapy were available. We used propensity score nearest-neighbor matching with replacement to balance the probability of receiving prior antiplatelet therapy between the prior antiplatelet therapy and no prior antiplatelet therapy group and adjusted for baseline prognostic factors to compare these groups. Primary outcome was symptomatic intracranial hemorrhage. Secondary outcomes were 90-day functional outcome (modified Rankin Scale), successful reperfusion (extended thrombolysis in cerebral infarction score ≥2B) and 90-day mortality.

Results

Thirty percent (n = 937) of the 3154 patients were on prior antiplatelet therapy, who were matched to 477 patients not on prior antiplatelet therapy. Symptomatic intracranial hemorrhage occurred in 74/937 (7.9%) patients on prior antiplatelet therapy and in 27/477 (5.6%) patients without prior antiplatelet therapy adjusted odds ratio 1.47, 95% confidence interval 0.86–2.49. No associations were found between prior antiplatelet therapy and functional outcome (adjusted common odds ratio 0.87, 95% confidence interval 0.65–1.16), successful reperfusion (adjusted odds ratio 1.23, 95% confidence interval 0.77–1.97), or 90-day mortality (adjusted odds ratio 1.15, 95% confidence interval 0.86–1.54).

Conclusion

We found no evidence of an association of prior antiplatelet therapy with the risk of symptomatic intracranial hemorrhage after endovascular treatment, nor on functional outcome, reperfusion, or mortality. A substantial beneficial or detrimental effect of antiplatelet therapy on clinical outcome cannot be excluded. A randomized clinical trial comparing antiplatelet therapy versus no antiplatelet therapy is needed.

In-vitro sonothrombolysis using thick-shelled polymer microbubbles - a comparison with thin-shelled microbubbles

BACKGROUND

Vascular thrombosis can be treated pharmacologically, however, serious shortcomings such as bleeding may occur. Several studies suggest that sonothrombolysis can induce lysis of the clots using ultrasound. Moreover, intravenously injected thin-shelled microbubbles (MBs) combined with ultrasound can further improve clot lysis. Thick-shelled MBs have been used for drug delivery, targeting and multimodal imaging. However, their capability to enhance sonothrombolysis is unknown. In this study, using an in-vitro set-up, the enhancement of clot lysis using ultrasound and thick-shelled MBs was investigated. Thin-shelled MBs was used for comparison.

METHOD

The main components in the in-vitro set-up was a vessel mimicking phantom, a pressure mearing system and programmable ultrasound machine. Blood clots were injected and entrapped on a pore mesh in the vessel phantom. Four different protocols for ultrasound transmission and MB exposure (7 blood clots/protocol) were considered together with a control test were no MBs and ultrasound were used. For each protocol, ultrasound exposure of 20 min was used. The upstream pressure of the partially occluded mesh was continuously measured to assess clot burden. At the end of each protocol blood clots were removed from the phantom and the clot mass loss was computed.

RESULTS

For the thick-shelled MBs no difference in clot mass loss compared with the control tests was found. A 10% increase in the clot mass loss compared with the control tests was found when using thin-shelled MBs and low pressure/long pulses ultrasound exposure. Similarly, in terms of upstream pressure over exposure time, no differences were found when using the thick-shelled MBs, whereas thin-shelled MBs showed a 15% decrease achieved within the first 4 min of ultrasound exposure.

CONCLUSION

No increase in clot lysis was achieved using thick-shelled MBs as demonstrated by no significant change in clot mass or upstream pressure. Although thick-shelled MBs are promising for targeting and drug delivery, they do not enhance clot lysis when considering the ultrasound sequences used in this study. On the other hand, ultrasound in combination with thin-shelled MBs can facilitate thrombolysis when applying long ultrasound pulses with low pressure.

[Reperfusion therapy in patients with minor or mild ischemic stroke]

A significant number of patients with minor or mild stroke symptoms on initial presentation subsequently develop neurological deterioration and poor clinical outcomes at hospital discharge. The presence of an underlying large vessel occlusion is a strong predictor of both clinical worsening and poor outcome. Although patients with a low baseline National Institutes of Health Stroke Scale (NIHSS) could have been included in some randomized controlled trials, the benefits of the mechanical thrombectomy for patients with a low NIHSS score are unknown. The causes of neurological deterioration in patients with underlying large vessel occlusion are heterogeneous, but include collateral failure, and no straightforward mechanisms are found in the majority of cases. Patients with internal carotid artery occlusion, but with a patent middle cerebral artery (MCA), can occasionally have good collateral circulation and develop only minor or mild stroke. These patients exhibit collateral MCA flow via the circle of Willis despite ipsilateral internal carotid artery occlusion. However, thrombus migration may cause occlusion of collateral MCA flow, leading to dramatic neurological deterioration. Careful observation and detailed assessment are required for the management of these patients. Recent studies have examined the efficacy and optimal timing of thrombolysis or mechanical thrombectomy for patients with minor or mild stroke. Herein, we review the mechanisms of neurological deterioration, and the efficacy of reperfusion therapy, for patients with minor or mild stroke.

Acute ischemic stroke patients with diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score ≤ 5 can benefit from endovascular treatment: a single-center experience and literature review

PURPOSE

The recommendation strength of the guidelines for mechanical thrombectomy among patients with large pre-treatment core infarct is weak. We evaluated the safety and outcome of endovascular treatment for acute ischemic stroke with diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) ≤ 5.

METHODS

Data on acute ischemic stroke patients with DWI-ASPECTS ≤ 5 who underwent endovascular treatment within 6 h, or presented an arterial spin labeling-DWI (ASL-DWI) mismatch within 12 h, at our center were retrospectively collected. We report the clinical characteristics and outcome of every patient, and review the relevant literature.

RESULTS

Among the 19 patients who were enrolled, all experienced successful reperfusion, and 10 achieved a favorable outcome (modified Rankin scale (mRS) ≤ 2). Two patients presented with symptomatic intracranial hemorrhage (sICH); both of them had a poor outcome (mRS > 2).

CONCLUSION

Acute ischemic stroke patients with large DWI lesions caused by large vessel occlusion can achieve a favorable clinical outcome with endovascular treatment if recanalization is performed within 6 h, or after 6 h in case of an ASL-DWI mismatch.

Advances in stroke pharmacology

Stroke occurs when a cerebral blood vessel is blocked or ruptured, and it is the major cause of death and adult disability worldwide. Various pharmacological agents have been developed for the treatment of stroke either through interrupting the molecular pathways leading to neuronal death or enhancing neuronal survival and regeneration. Except for rtPA, few of these agents have succeeded in clinical trials. Recently, with the understanding of the pathophysiological process of stroke, there is a resurrection of research on developing neuroprotective agents for stroke treatment, and novel molecular targets for neuroprotection and neurorestoration have been discovered to predict or offer clinical benefits. Here we review the latest major progress of pharmacological studies in stroke, especially in ischemic stroke; summarize emerging potential therapeutic mechanisms; and highlight recent clinical trials. The aim of this review is to provide a panorama of pharmacological interventions for stroke and bridge basic and translational research to guide the clinical management of stroke therapy.

Neuroprotective Effect of Sirt2-specific Inhibitor AK-7 Against Acute Cerebral Ischemia is P38 Activation-dependent in Mice

Cerebral ischemia is the most common cause of stroke with high morbidity, disability and mortality. Sirtuin-2 (Sirt2), a vitally important NAD⁺-dependent deacetylase which has been widely researched in central nervous system diseases, has also been identified as a promising treatment target using its specific inhibitors such as AK-7. In this study, we found that P38 was specifically activated after focal cerebral ischemic injury, and it was also significantly activated after AK-7 administration in a concentration-dependent manner in vitro and in vivo. AK-7 decreased the infarction volume remarkably and promoted the recovery of neurological function efficiently in the mice evaluated by behavior tests. In contrast, pP38 inhibition increased the infarct volume and exacerbated the symptoms of paralysis. Herein, we suggest AK-7 improves the outcome of brain ischemia in dependence on the P38 activation in mice, which may serve as a strategy for the treatment of stroke.

Antiplatelet pretreatment and outcomes following mechanical thrombectomy for emergent large vessel occlusion strokes

BACKGROUND

Few data are available regarding the safety and efficacy of antiplatelet (APT) pretreatment in acute ischemic stroke (AIS) patients with emergent large vessel occlusions (ELVO) treated with mechanical thrombectomy (MT). We sought to evaluate the association of APT pretreatment with safety and efficacy outcomes following MT for ELVO.

METHODS

Consecutive ELVO patients treated with MT during a 4-year period in a tertiary stroke center were evaluated. The following outcomes were documented using standard definitions: symptomatic intracranial hemorrhage (sICH), successful recanalization (SR; modified TICI score 2b/3), mortality, and functional independence (modified Rankin Scale scores of 0-2).

RESULTS

The study population included 217 patients with ELVO (mean age 62±14 years, 50% men, median NIH Stroke Scale score 16). APT pretreatment was documented in 71 cases (33%). Patients with APT pretreatment had higher SR rates (77% vs 61%; P=0.013). The two groups did not differ in terms of sICH (6% vs 7%), 3-month mortality (25% vs 26%), and 3-month functional independence (50% vs 48%). Pretreatment with APT was independently associated with increased likelihood of SR (OR 2.18, 95% CI1.01 to 4.73; P=0.048) on multivariable logistic regression models adjusting for potential confounders. A significant interaction (P=0.014) of intravenous thrombolysis (IVT) pretreatment on the association of pre-hospital antiplatelet use with SR was detected. APT pretreatment was associated with SR (OR 2.74, 95% CI 1.15 to 6.54; P=0.024) in patients treated with combination therapy (IVT and MT) but not in those treated with direct MT (OR 1.78, 95% CI 0.63 to 5.03; P=0.276).

CONCLUSION

APT pretreatment does not increase the risk of sICH and may independently improve the odds of SR in patients with ELVO treated with MT. The former association appears to be modified by IVT.

Improving Cerebral Blood Flow after Arterial Recanalization: A Novel Therapeutic Strategy in Stroke

Ischemic stroke is caused by a disruption in blood supply to a region of the brain. It induces dysfunction of brain cells and networks, resulting in sudden neurological deficits. The cause of stroke is vascular, but the consequences are neurological. Decades of research have focused on finding new strategies to reduce the neural damage after cerebral ischemia. However, despite the incredibly huge investment, all strategies targeting neuroprotection have failed to demonstrate clinical efficacy. Today, treatment for stroke consists of dealing with the cause, attempting to remove the occluding blood clot and recanalize the vessel. However, clinical evidence suggests that the beneficial effect of post-stroke recanalization may be hampered by the occurrence of microvascular reperfusion failure. In short: recanalization is not synonymous with reperfusion. Today, clinicians are confronted with several challenges in acute stroke therapy, even after successful recanalization: (1) induce reperfusion, (2) avoid hemorrhagic transformation (HT), and (3) avoid early or late vascular reocclusion. All these parameters impact the restoration of cerebral blood flow after stroke. Recent advances in understanding the molecular consequences of recanalization and reperfusion may lead to innovative therapeutic strategies for improving reperfusion after stroke. In this review, we will highlight the importance of restoring normal cerebral blood flow after stroke and outline molecular mechanisms involved in blood flow regulation.

Progression in acute ischemic stroke: Is widespread atherosclerotic background a risk factor?

OBJECTIVES

In this study, we aimed to investigate the causes and conditions related with progression and outcome of progressive acute ischemic stroke.

PATIENTS AND METHODS

In this prospective study, a total of 78 acute ischemic stroke patients (32 males, 46 females; mean age 70±12.8 years; range 34 to 95 years) were included between February 2006 and October 2010. The patients were classified into two groups as those with and without progression according to the National Institute of Health Stroke Scale (NIHSS). Risk factors for ischemic stroke, stroke subtypes, and radiological investigations and prognosis were compared between the progressive and non-progressive patients.

RESULTS

Neurological deterioration occurred in 12 patients (15%). Progressive acute ischemic stroke patients had carotid stenosis compared to non-progressive patients (50% vs 19%), and ischemic cardiac disease (33% vs 6%) more common in the patients with progression. Mortality during hospital stay and long term-outcomes were similar between the groups.

CONCLUSION

Our study results suggest that widespread atherosclerotic diseases may induce neurological progression.

Comparison of multimodal intra-arterial treatment versus intravenous thrombolysis for hypertensive patients with severe large vessel cerebral infarction

Since intravenous thrombolysis (IVT) is often associated with poor outcomes in hypertensive patients with severe acute cerebral infarction (ACI) due to occlusions of the internal carotid, basilar, or proximal middle cerebral artery, we evaluated whether multimodal intra-arterial treatment (IAT) might improve functional outcomes in this patient population. We retrospectively reviewed the charts of eligible patients who underwent multimodal IAT including intra-arterial thrombolysis, mechanical thrombectomy, balloon and/or stent angioplasty (IAT group) or IVT alone (IVT group). Outcomes included the revascularization rate 24 hours postprocedure, the frequency of survival at 7, 90, and 180 days postonset, and a measure of functional outcomes using the modified Rankin Scale (mRS). The IAT group included 62 patients and the IVT group included 31 patients. Multimodal IAT increased the revascularization rate at 24 hours (p<0.001) and the frequency of survival and functional independence (mRS ≤2) at 7 days (p<0.001 and p=0.018, respectively), 90 days (both p<0.001), and 180 days (both p<0.001). Independent predictors of longer survival were treatment with multimodal IAT (HR 0.1; 95% CI 0.0 to 0.4; p<0.001) and revascularization (HR 0.1; 95% CI 0.0 to 0.4; p<0.001), whereas a longer duration from onset to treatment was a risk factor for death (HR 1.4; 95% CI 1.2 to 1.8; p<0.001). There was no significant between-group difference for symptomatic hemorrhagic transformation. This study found that for patients with severe hypertensive ACI with large vessel occlusions, multimodal IAT improved the outcomes, including early revascularization, survival, and functional outcome.

Statin and Aspirin Pretreatment Are Associated with Lower Neurological Deterioration and Platelet Activity in Patients with Acute Ischemic Stroke

BACKGROUND

Aspirin and statin are recommended for the treatment of acute ischemic stroke. However, whether aspirin and statin pretreatment is associated with clinical outcomes has not been well addressed. This study aimed to evaluate the effect of pre-existing statin and aspirin use on platelet activation and clinical outcome in acute ischemic stroke patients.

METHODS

We conducted a prospective, multicenter observational study in patients with acute ischemic stroke. Platelet aggregation and platelet-leukocyte aggregates were measured on admission and during 7-10 days after admission. The primary outcome of the study was neurological deterioration (ND) within 10 days after admission. The secondary outcome was a composite of recurrent ischemic stroke, myocardial infarction, and death during the first 3 months after admission. Physical disability was evaluated using the modified Rankin Scale score at 3 months after admission.

RESULTS

Among 1124 enrolled patients, 270 (24%) experienced ND. Higher platelet aggregation and platelet-leukocyte aggregates on admission and during 7-10 days were associated with ND. Platelet aggregation and platelet-leukocyte aggregates on admission were significantly lower in the patients with pre-existing statin or aspirin use than those without treatment. Patients with prestroke concomitant statin and aspirin treatment had significantly lower incidence of ND than those without treatment. Diabetes mellitus, fasting glucose, platelet-leukocyte aggregates, and prestroke concomitant statin and aspirin use were independently associated with ND.

CONCLUSIONS

Prestroke concomitant statin and aspirin use is associated with lower neurological deterioration and platelet activity in patients with acute ischemic stroke.

Clot Formation in the Presence of Acetylsalicylic Acid Leads to Increased Lysis Rates Regardless of the Chosen Thrombolysis Strategy

BACKGROUND

Patients with acute ischemic strokes frequently take an acetylsalicylic acid (ASA) premedication. We determined the impact of ASA on different thrombolysis strategies in vitro.

METHODS

For two clot types made from platelet-rich plasma (one with and one without ASA) lysis rates were measured by weight loss after 1 h for five different groups: in control group A clots were solely placed in plasma; in groups B and C clots were treated with rt-PA (60 kU/ml), and in groups D and E clots were treated with desmoteplase (DSPA; 2 µg/ml). Ultrasound (2 MHz, 0.179 W/cm2) was included in groups C and E. The fibrin mesh structures of the clots were investigated by electron microscopy.

RESULTS

For both clot types lysis rates increased significantly for all treatment strategies compared to their control group (each p < 0.001). The addition of ASA significantly increased the lysis rate in all 5 groups (each p < 0.001) and led to a ceiling effect concerning the treatment. A semiquantitative analysis of transmission electron micrographs revealed a decreased fibrin density for clots with ASA. For both clot types DSPA and ultrasound led to a significant dissolution of the fibrin mesh (both p = 0.029).

CONCLUSIONS

In vitro ASA pretreatment leads to significantly increased lysis rates due to a weaker fibrin mesh in platelet-rich plasma clots.

Early neurological stability predicts adverse outcome after acute ischemic stroke

Background Deterioration in the National Institutes of Health Stroke Scale (NIHSS) in the early days after stroke is associated with progressive infarction, brain edema, and/or hemorrhage, leading to worse outcome. Aims We sought to determine whether a stable NIHSS score represents an adverse or favorable course. Methods Brain magnetic resonance images from a research cohort of acute ischemic stroke patients were analyzed. Using NIHSS scores at baseline and follow-up (day 3-5), patients were categorized into early neurological deterioration (ΔNIHSS ≥ 4), early neurological recovery (ΔNIHSS ≤ -4) or early neurological stability (ΔNIHSS between -3 and 3). The association between these categories and volume of infarct growth, volume of swelling, parenchymal hemorrhage, and 3-month modified Rankin Scale score were evaluated. Results Patients with early neurological deterioration or early neurological stability were less likely to be independent (modified Rankin Scale = 0-2) at 3 months compared to those with early neurological recovery ( P < 0.001). Patients with early neurological deterioration or early neurological stability were observed to have significantly greater infarct growth and swelling volumes than those with early neurological recovery ( P = 0.03; P < 0.001, respectively). Brain edema was more common than the other imaging markers investigated and was independently associated with a stable or worsening NIHSS score after adjustment for age, baseline stroke volume, infarct growth volume, presence of parenchymal hemorrhage, and reperfusion ( P < 0.0001). Conclusions Stable NIHSS score in the subacute period after ischemic stroke may not be benign and is associated with tissue injury, including infarct growth and brain edema. Early improvement is considerably more likely to occur in the absence of these factors.

Serial NIHSS scores in patients with acute cerebral infarction

AIM

To study time course of neurological deficits in patients with acute cerebral infarction admitted shortly after stroke onset.

METHODS

Serial NIHSS scores were obtained whenever feasible in patients admitted because of cerebral infarction within 3 h of symptom onset. Patients receiving and not receiving thrombolysis were compared. Short-term outcome was defined as NIHSS score and modified Rankin score 7 days after stroke onset. The hyperacute phase was defined as the time between stroke onset and the 6- to 9-h interval after stroke onset, acute phase as the time between the 6- to 9-h interval and the 21 to 27-h interval, and the subacute phase as the time between the 21- to 27-h interval and 7 days after stroke onset.

RESULTS

Serial NIHSS scores were obtained in 552 patients within three hours of stroke onset. There was a significant improvement (P < 0.001) comprising 62% of the total improvement in the hyperacute phase. There was no significant improvement in the acute phase and a small significant improvement in the subacute phase (P < 0.01).

CONCLUSION

Our study demonstrates a hyperacute phase with rapid improvement probably due to early recanalization, an acute phase with no significant improvement and slow improvement in the subacute phase. Different pathophysiological mechanisms are likely involved in the different phases.

Early Neurologic Deterioration after Stroke Depends on Vascular Territory and Stroke Etiology

BACKGROUND AND PURPOSE

Early neurologic deterioration (END) occurs in up to one-third of patients with ischemic stroke and is associated with poor outcomes. The purpose of the present study was to determine which stroke etiologies and vascular distributions pose a greater threat of END in stroke patients.

METHODS

Using a single-center registry of prospectively maintained clinical data, adult ischemic stroke patients admitted (July 2008 to June 2014) within 48 hours of symptom onset were evaluated according to stroke etiology and vascular distribution using diffusion-weighted MRI. Major stroke etiologies were divided into cardioembolic, large vessel, small vessel, other, unknown source, and multiple possible etiologies. END was defined as a worsening of 2 or more points on the National Institutes of Health Stroke Scale during a 24-hour period of hospitalization. Crude and backward stepwise regression models were generated to associate stroke etiology and vascular distribution with END.

RESULTS

Of the included 961 patients (median age 65 years, 47% female, 72% non-White), 323 (34%) experienced END. Strokes involving the internal carotid artery (ICA) were associated with a threefold higher odds of END in stepwise regression models (OR 3.0, 95% CI 1.4-6.6, P=0.006). Among stroke etiologies, those with unclear mechanisms had the lowest odds of END in the fully adjusted model (OR 0.6, 95% CI 0.4-1.0, P=0.029).

CONCLUSIONS

In our single-center cohort of patients, ICA infarctions were independently associated with END whereas strokes of unknown etiology were least often associated with END. Larger cohorts are necessary to determine which steps, if any, can be taken to prevent END in these vulnerable populations.

Early neurological deterioration after thrombolysis: Clinical and imaging predictors

BACKGROUND

National Institutes of Health Stroke Scale is the most common scale used in stroke patients. An increase of four points or more within 24 h signifies early neurological deterioration. We aimed to establish how often early neurological deterioration occurs in a cohort selected by magnetic resonance imaging and which factors predicted early neurological deterioration.

METHODS

In this single-center study, we collected epidemiological, imaging and outcome data on 569 consecutive patients undergoing reperfusion therapy after magnetic resonance imaging selection.

RESULTS

Of these, 33 (5.8%) experienced early neurological deterioration. Seven were due to a symptomatic intracerebral hemorrhage, 23 were caused by extension of ischemia on follow-up imaging and three were due to progression on the basis of small vessel disease. Early neurological deterioration was predicted by a larger perfusion lesion, higher blood glucose and presence of large vessel disease. Penumbra occurred in 34% of patients but only 9% of patients with penumbra experienced early neurological deterioration, thus eroding the value of penumbra as an imaging marker. Early neurological deterioration was a poor prognostic sign. Odds ratio for disability or death was 14.9 (95% confidence interval: 6.5-34.0).

CONCLUSION

Early neurological deterioration is rare. It originates mainly from ischemic infarct growth rather than from hemorrhage. Concern should be highest in patients with elevated blood glucose, larger perfusion lesions and large vessel disease. Prior aspirin use increases risk of symptomatic intracerebral hemorrhage.

Clinical Deterioration and Early Imaging Changes after Intravenous Tissue Plasminogen Activator Administration in Acute Ischemic Stroke Patients

BACKGROUND AND PURPOSE

Clinical worsening is a known complication following acute ischemic stroke. This study attempted to determine the mechanism of deterioration by correlating clinical findings with changes on computed tomography or magnetic resonance.

METHODS

From a single university medical center, 30 consecutive acute ischemic stroke patients who received intravenous tissue plasminogen activator within 3 hours of symptom onset during a 3-year period were identified from a quality database that included all hospitalized patients either admitted with strokes or with in-hospital strokes. Images were reviewed by a single neuroradiologist for changes including edema, extension of infarct, hemorrhage, herniation, and midline shift and were correlated to National Institutes of Health Stroke Scale (NIHSS) scores obtained from data in the medical chart.

RESULTS

Ten patients had documented clinical deterioration with a corresponding increase in the NIHSS score. Of these, 4 patients had follow-up scans that showed worsening changes concurrent with deterioration. In the 20 patients who remained clinically stable, 3 patients had worsening changes on follow-up scans. Patients who deteriorated were no more likely to have imaging changes than those who had a stable clinical course. Appearance of herniation, both subfalcine and uncal, was the only specific imaging change associated with clinical deterioration.

CONCLUSIONS

This study demonstrates that processes besides hemorrhage, including edema, midline shift, herniation, extension of infarct, and new infarct, are neither frequent nor specific for predicting clinical course. Other factors associated with these processes that may or may not be quantifiable on imaging are likely involved. Furthermore, in over half of the cases of worsening, deterioration occurs without associated imaging, metabolic, or infectious etiologies.

Time to Neurological Deterioration in Ischemic Stroke

BACKGROUND

Neurological deterioration (ND) is common, with nearly one-half of ND patients deteriorating within the first 24 to 48 hours of stroke. The timing of ND with respect to ND etiology and reversibility has not been investigated.

METHODS

At our center, we define ND as an increase of 2 or more points in the National Institutes of Health Stroke Scale (NIHSS) score within 24 hours and categorize etiologies of ND according to clinical reversibility. ND etiologies were considered non-reversible if such causes may have produced or extended any areas of ischemic neurologic injury due to temporary or permanent impairment in cerebral perfusion.

RESULTS

Seventy-one of 350 ischemic stroke patients experienced ND. Over half (54.9%) of the patients who experienced ND did so within the 48 hours of last seen normal. The median time to ND for non-reversible causes was 1.5 days (IQR 0.9, 2.4 days) versus 2.6 days for reversible causes (IQR 1.4, 5.5 days, p=0.011). After adjusting for NIHSS and hematocrit on admission, the log-normal survival model demonstrated that for each 1-year increase in a patient's age, we expect a 3.9% shorter time to ND (p=0.0257). In addition, adjusting for age and hematocrit on admission, we found that that for each 1-point increase in the admission NIHSS, we expect a 3.1% shorter time to ND (p=0.0034).

CONCLUSIONS

We found that despite having similar stroke severity and age, patients with nonreversible causes of ND had significantly shorter median time to ND when compared to patients with reversible causes of ND.

Functional outcomes and recanalization rates of stent retrievers in acute ischaemic stroke: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Intra-arterial therapy for acute ischaemic stroke has evolved rapidly in the last few years. Stent retrievers have now replaced 'first-generation' devices, which have been the principle devices tested in stroke trials.Our aims were to determine the rates of successful recanalization and functional independence in acute stroke patients treated with stent retrievers. We also sought to assess the safety outcomes of stent retrievers by assessing the rates of mortality and intra-cranial haemorrhage.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis of studies which utilized stent retrievers as sole treatment or as part of a multi-modal approach in acute ischaemic stroke.

RESULTS

We identified 20 eligible studies: 17 on Solitaire (ev3/Covidien, Irvine, California, USA) (n = 762) and three on Trevo (Stryker, Kalamazoo, Michigan, USA) (n = 210). The mean age of participants was 66.8 (range 62.1-73.0) years and the M:F ratio was 1.1:1. The average stroke severity score (National Institutes of Health Stroke Scale (NIHSS)) at presentation was 17.2. The weighted mean symptom onset to arterial puncture and procedural duration were 265.4 minutes and 54.8 minutes, respectively.Successful recanalization was achieved in 84.5% of patients with a weighted mean of 2.0 stent retriever passes. Independent functional outcome was achieved in 51.2% and the mortality rate was 16.8%.

CONCLUSION

Stent retrievers have the potential to achieve a high rate of recanalization and functional independence whilst being relatively safe. They should be assessed in well-designed randomized controlled trials to determine their efficacy and assess whether they compare favourably with 'standard treatment' in stroke.

Daily National Institutes of Health Stroke Scale examinations at stroke centers: why not do them?

The National Institutes of Health Stroke Scale was originally designed to stratify patients according to stroke severity for clinical trials, and now it is used to predict disposition and prognosticate functional outcome. Many researchers have also adopted it to trend patient progress over time and detect early neurologic deterioration. However, few investigators have reported its utility in monitoring the daily progress of patients hospitalized for stroke. In the present article, the authors discuss the advantages of daily National Institutes of Health Stroke Scale assessments and our clinical experience with this invaluable tool.

Incidence, causes and predictors of neurological deterioration occurring within 24 h following acute ischaemic stroke: a systematic review with pathophysiological implications

Early neurological deterioration (END) following ischaemic stroke is a serious event with manageable causes in only a fraction of patients. The incidence, causes and predictors of END occurring within 24 h of acute ischaemic stroke (END24) have not been systematically reviewed. We systematically reviewed Medline and Embase from January 1990 to April 2013 for all studies on END24 following acute ischaemic stroke (<8 h from onset). We recorded the incidence and presumed causes of and factors associated with END24. Thirty-six studies were included. Depending on the definition used, the incidence of END24 markedly varied among studies. Using the most widely used change in National Institutes of Health Stroke Scale ≥4 definition, the pooled incidence was 13.8% following thrombolysis, ascribed to intracranial haemorrhage and malignant oedema each in ∼20% of these. As other mechanisms were rarely reported, in the majority no clear cause was identified. Few data on END24 occurring in non-thrombolysed patients were available. Across thrombolysed and non-thrombolysed samples, the strongest and most consistent admission predictors were hyperglycaemia, no prior aspirin use, prior transient ischaemic attacks, proximal arterial occlusion and presence of early CT changes, and the most consistent 24 h follow-up associated factors were no recanalisation/reocclusion, large infarcts and intracranial haemorrhage. Finally, END24 was strongly predictive of poor outcome. The above findings are discussed with emphasis on END without a clear mechanism. Data on incidence and predictors of the latter subtype is scarce, and future studies using systematic imaging protocols should address its underlying pathophysiology. This may in turn lead to rational preventative and therapeutic measures for this ominous event.

Thrombolysis for acute ischaemic stroke

BACKGROUND

Most strokes are due to blockage of an artery in the brain by a blood clot. Prompt treatment with thrombolytic drugs can restore blood flow before major brain damage has occurred and improve recovery after stroke in some people. Thrombolytic drugs, however, can also cause serious bleeding in the brain, which can be fatal. One drug, recombinant tissue plasminogen activator (rt-PA), is licensed for use in selected patients within 4.5 hours of stroke in Europe and within three hours in the USA. There is an upper age limit of 80 years in some countries, and a limitation to mainly non-severe stroke in others. Forty per cent more data are available since this review was last updated in 2009.

OBJECTIVES

To determine whether, and in what circumstances, thrombolytic therapy might be an effective and safe treatment for acute ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched November 2013), MEDLINE (1966 to November 2013) and EMBASE (1980 to November 2013). We also handsearched conference proceedings and journals, searched reference lists and contacted pharmaceutical companies and trialists.

SELECTION CRITERIA

Randomised trials of any thrombolytic agent compared with control in people with definite ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors applied the inclusion criteria, extracted data and assessed trial quality. We verified the extracted data with investigators of all major trials, obtaining additional unpublished data if available.

MAIN RESULTS

We included 27 trials, involving 10,187 participants, testing urokinase, streptokinase, rt-PA, recombinant pro-urokinase or desmoteplase. Four trials used intra-arterial administration, while the rest used the intravenous route. Most data come from trials that started treatment up to six hours after stroke. About 44% of the trials (about 70% of the participants) were testing intravenous rt-PA. In earlier studies very few of the participants (0.5%) were aged over 80 years; in this update, 16% of participants are over 80 years of age due to the inclusion of IST-3 (53% of participants in this trial were aged over 80 years). Trials published more recently utilised computerised randomisation, so there are less likely to be baseline imbalances than in previous versions of the review. More than 50% of trials fulfilled criteria for high-grade concealment; there were few losses to follow-up for the main outcomes.Thrombolytic therapy, mostly administered up to six hours after ischaemic stroke, significantly reduced the proportion of participants who were dead or dependent (modified Rankin 3 to 6) at three to six months after stroke (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.78 to 0.93). Thrombolytic therapy increased the risk of symptomatic intracranial haemorrhage (OR 3.75, 95% CI 3.11 to 4.51), early death (OR 1.69, 95% CI 1.44 to 1.98; 13 trials, 7458 participants) and death by three to six months after stroke (OR 1.18, 95% CI 1.06 to 1.30). Early death after thrombolysis was mostly attributable to intracranial haemorrhage. Treatment within three hours of stroke was more effective in reducing death or dependency (OR 0.66, 95% CI 0.56 to 0.79) without any increase in death (OR 0.99, 95% CI 0.82 to 1.21; 11 trials, 2187 participants). There was heterogeneity between the trials. Contemporaneous antithrombotic drugs increased the risk of death. Trials testing rt-PA showed a significant reduction in death or dependency with treatment up to six hours (OR 0.84, 95% CI 0.77 to 0.93, P = 0.0006; 8 trials, 6729 participants) with significant heterogeneity; treatment within three hours was more beneficial (OR 0.65, 95% CI 0.54 to 0.80, P < 0.0001; 6 trials, 1779 participants) without heterogeneity. Participants aged over 80 years benefited equally to those aged under 80 years, particularly if treated within three hours of stroke.

AUTHORS' CONCLUSIONS

Thrombolytic therapy given up to six hours after stroke reduces the proportion of dead or dependent people. Those treated within the first three hours derive substantially more benefit than with later treatment. This overall benefit was apparent despite an increase in symptomatic intracranial haemorrhage, deaths at seven to 10 days, and deaths at final follow-up (except for trials testing rt-PA, which had no effect on death at final follow-up). Further trials are needed to identify the latest time window, whether people with mild stroke benefit from thrombolysis, to find ways of reducing symptomatic intracranial haemorrhage and deaths, and to identify the environment in which thrombolysis may best be given in routine practice.

Neurofluctuation in patients with subcortical ischemic stroke

OBJECTIVE

The purpose of this study was to assess the incidence of deterioration, fluctuation, and associated risk of poor outcome in patients with subcortical stroke (SCS).

METHODS

We conducted a prospective observational study, enrolling patients admitted with SCS based on their clinical examination and imaging studies. An NIH Stroke Scale evaluation was performed daily and whenever deterioration in examination was detected. Neurologic deterioration was defined as a motor score increase of at least 1 on the NIH Stroke Scale. Modified Rankin Scale scores at discharge were used to assess outcome.

RESULTS

Among 90 enrolled patients, 37 (41%) deteriorated, 75% of them in the first 24 hours after enrollment. Administration of tissue plasminogen activator was significantly associated with deterioration (hazard ratio 2.25; 95% confidence interval [CI]: 1.13-4.49) even after controlling for the association of deterioration with the early poststroke period. Deterioration conferred an increased risk of poor outcome (modified Rankin Scale scores 3-6) at discharge (relative risk: 1.80; 95% CI: 1.71-1.93). Reversion back to predeterioration deficits occurred in 38% of patients, and was associated with reduced risk of poor outcome at discharge (relative risk: 0.12; 95% CI: 0.02-0.83). Treatment with tissue plasminogen activator conferred better chances of spontaneous recovery to predeterioration deficits after initial deterioration (hazard ratio: 4.36; 95% CI: 1.36-14.01).

CONCLUSION

More than 40% of patients with SCS deteriorate neurologically. Deterioration tends to occur early after stroke, spontaneously reverses in approximately one-third of cases, and poses an increased risk of poor outcome. Therapies are needed to prevent, arrest, or reverse deterioration in patients with SCS.

Outcome prediction in acute stroke patients considered for endovascular treatment: a novel tool

Functional outcome following emergent intra-arterial thrombectomy is variable and likely reflects the heterogeneous characteristics of acute stroke patients. The aims of our study were (1) to study which pre-treatment variables correlate with functional outcome and (2) to devise a tool which would reliably predict outcome. Prospective data of patients treated with intra-arterial mechanical thrombectomy in our institution between 2010 and 2012 were collected. A preliminary univariate analysis of baseline variables was performed and data outliers were identified by constructing scatter and box plots. Systematic bivariate analysis was then carried out using a linear regression model and the individual contributing weights of the variables to outcome calculated. The B and constant values from the regression were used to construct a predictive formula. Fifty-seven patients, 35 males (61.4%) and 22 females (38.6%) with a mean age of 62.3 years (range 26-87) were included in the cohort. Statistical correlations of baseline variables and functional outcome showed that age, National Institutes of Health Stroke Scale at presentation and CT leptomeningeal collaterals were strongly correlated (p<0.01), and were later included in the linear regression model. A tool was devised from the regression formula combining weighted inputs of the three variables. Regression statistics and residual analysis were then performed to assess the accuracy and reliability of the proposed tool. The proposed tool is easy to use and reliably predicts functional outcome prior to endovascular therapy. It may help clinical decision-making in the acute setting and offers 'tailor-made' outcome expectations.

Platelet-oriented inhibition in new TIA and minor ischemic stroke (POINT) trial: rationale and design

BACKGROUND

Ischemic stroke and other vascular outcomes occur in 10-20% of patients in the three-months following a transient ischemic attack or minor ischemic stroke, and many are disabling. The highest risk period for these outcomes is the early hours and days immediately following the ischemic event. Aspirin is the most common antithrombotic treatment used for these patients.

AIM

The aim of POINT is to determine whether clopidogrel plus aspirin taken <12 h after transient ischemic attack or minor ischemic stroke symptom onset is more effective in preventing major ischemic vascular events at 90 days in the high-risk, and acceptably safe, compared with aspirin alone.

DESIGN

POINT is a prospective, randomized, double-blind, multicenter trial in patients with transient ischemic attack or minor ischemic stroke. Subjects are randomized to clopidogrel (600 mg loading dose followed by 75 mg/day) or matching placebo, and all will receive open-label aspirin 50-325 mg/day, with a dose of 162 mg daily for five-days followed by 81 mg daily strongly recommended.

STUDY OUTCOMES

The primary efficacy outcome is the composite of new ischemic vascular events - ischemic stroke, myocardial infarction, or ischemic vascular death - by 90 days. The primary safety outcome is major hemorrhage, which includes symptomatic intracranial hemorrhage.

DISCUSSION

Aspirin is the most common antithrombotic given to patients with a stroke or transient ischemic attack, as it reduces the risk of subsequent stroke. This trial expects to determine whether more aggressive antithrombotic therapy with clopidogrel plus aspirin, initiated acutely, is more effective than aspirin alone.

Re-endovascular recanalization for acute middle cerebral artery reocclusion after surgical embolectomy

A 62-year-old woman with atrial fibrillation underwent burr hole trephination for a chronic subdural hematoma. Two days later the patient suddenly presented with motor dysphasia and slightly decreased motor power. Time of flight MR angiography revealed distal M1 occlusion without diffusion restriction. Stent-assisted mechanical thrombectomy was attempted but failed. Post-procedure MRI illustrated a small area of diffusion restriction within the peri-insular and parietal areas. Immediate surgical embolectomy was performed but reocclusion of M1 was documented in the postoperative angiography. Stent-assisted revascularization with a Solitaire stent was conducted and immediate restoration of blood flow was observed. The patient's motor weakness and motor dysphasia recovered fully. Re-endovascular intervention can be beneficial in selected patients for acute middle cerebral artery reocclusion after surgical embolectomy when endovascular thrombectomy fails.

Clinical, angiographic and radiographic outcome differences among mechanical thrombectomy devices: initial experience of a large-volume center

BACKGROUND AND PURPOSE

Higher reperfusion rates have been established with endovascular treatment of acute ischemic stroke (AIS). There are limited data on the comparative performance of mechanical thrombectomy devices.

METHODS

A retrospective single-center analysis was undertaken of all consecutive patients who underwent thrombectomy using Merci, Penumbra or stent retrievers (SR) from September 2010 to November 2012. Baseline characteristics, rates of successful recanalization (modified Thrombolysis in Cerebral Infarction (mTICI) score 2b-3), symptomatic intracerebral hemorrhage (sICH), final infarct volume, 90-day mortality and independent functional outcomes at 90 days were compared across the three devices.

RESULTS

Our cohort included 287 patients. There were mild imbalances in baseline characteristics with trends towards higher National Institutes of Health Stroke Scale (NIHSS) score in patients in the Merci group (SR=18 vs Merci=21 vs Penumbra=19, p=0.06) and lower Alberta Stroke Program Early CT Score (ASPECTS) in patients in the SR group (>7: SR=51% vs Merci=61% vs Penumbra=62%, p=0.12). On univariate analysis there were no differences in the rate of sICH (SR=7% vs Merci=7% vs Penumbra=6%, p=0.921) and infarct volume (SR=61.5 mL vs Merci=69.5 mL vs Penumbra=59.2 mL, p=0.621). Trends towards better functional outcomes were found with Penumbra and SR vs Merci (41% vs 36% vs 25%, respectively, p=0.079). Complete or near complete reperfusion (mTICI 2b-3) was higher in the SR and Penumbra groups than in the Merci group (86% vs 78% vs 70%, respectively, p=0.027). Binary logistic regression showed that SR was an independent predictor of good functional outcome (OR 2.27, 95% CI 1.018 to 5.048; p=0.045).

CONCLUSIONS

Although our initial data confirm the superiority of SR technology over the Merci device, there was no significant difference in near complete/complete reperfusion, final infarct volumes or clinical outcomes between SR and Penumbra thromboaspiration.