Low-Versus Standard-Dose Alteplase for Ischemic Strokes Within 4.5 Hours: A Comparative Effectiveness and Safety Study

Retrospective Evaluation of the Results of Low-Dose Intravenous Thrombolytic Therapy in Acute Ischemic Stroke

Objectives

This study aimed to investigate the clinical data of patients with acute ischemic stroke who received low-dose intravenous (IV) thrombolytic therapy (0.9 mg/kg; maximum 50 mg) for various reasons, compare the obtained results with those of patients who received standard-dose thrombolytic therapy, and discuss them in light of the literature.

Methods

Patients who received IV thrombolytic therapy within 4.5 h of symptom onset between January 2015 and June 2018 were retrospectively reviewed. Patients were divided into the low-dose group (0.9 mg/kg; max. 50 mg) and the standard-dose group (0.9 mg/kg; max 90 mg) according to the thrombolytic therapy dose, after which demographic data and clinical results were analyzed.

Results

A total of 109 patients receiving thrombolytic therapy (19 patients in the low-dose group and 90 patients in the standard-dose group) were included in the study. There was no significant difference between the two groups in terms of good outcome rates (47.4% vs. 52.2%). There was no statistically significant difference in terms of symptomatic and asymptomatic intracerebral hemorrhage rates.

Conclusion

Our study showed similar efficacy and safety for low-dose IV thrombolytic therapy compared with standard-dose IV thrombolytic therapy administered within 4.5 h of symptom onset in patients with acute ischemic stroke.

Magnetic Nanoparticles Mediated Thrombolysis-A Review

Nanoparticles containing thrombolytic medicines have been developed for thrombolysis applications in response to the increasing demand for effective, targeted treatment of thrombosis disease. In recent years, there has been a great deal of interest in nanoparticles that can be navigated and driven by a magnetic field. However, there are few review publications concerning the application of magnetic nanoparticles in thrombolysis. In this study, we examine the current state of magnetic nanoparticles in the application of in vitro and in vivo thrombolysis under a static or dynamic magnetic field, as well as the combination of magnetic nanoparticles with an acoustic field for dual-mode thrombolysis. We also discuss four primary processes of magnetic nanoparticles mediated thrombolysis, including magnetic nanoparticle targeting, magnetic nanoparticle trapping, magnetic drug release, and magnetic rupture of blood clot fibrin networks. This review will offer unique insights for the future study and clinical development of magnetic nanoparticles mediated thrombolysis approaches.

Comparison of Effectiveness and Safety of Low-Dose Versus Standard-Dose Intravenous Recombinant Tissue Plasminogen Activator in Patients With Acute Ischemic Stroke: A Meta-Analysis

The aim of the present meta-analysis is to compare the efficacy and safety of low-dose and standard-dose recombinant tissue plasminogen activators (r-tPA) in patients with acute ischemic stroke. The present meta-analysis was conducted according to the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines. We conducted a systematic search in PubMed, Embase, and the Cochrane Library to identify studies published between January 1, 2010, and January 31, 2023, using the following terms: "stroke," "alteplase," "doses," "efficacy," "tissue plasminogen activator," "r-tPA," and "safety." Primary efficacy outcomes included favorable outcomes (Modified Rankin Scale scores of 0-2), while secondary efficacy outcome was all-cause mortality at 90 days. Safety outcomes included asymptomatic intracerebral hemorrhage (ICH) and symptomatic ICH assessed using the National Institute of Neurological Disorders and Stroke (NINDS) study and the Safe Implementation of Thrombolysis in Stroke-Monitoring (SITS-MOST) study. We also compared parenchymal hematomas as safety outcome between the two groups defined by the authors themselves in their research. A total of 16 studies were included in the present meta-analysis. The meta-analysis did not report any significant difference between low-dose and standard-dose r-tPA in terms of mortality, symptomatic intracranial hemorrhage (SICH), asymptomatic ICH, and parenchymal hematomas. However, the favorable outcome was significantly greater in patients receiving a standard dose of r-tPA.

Efficacy and Safety of Anticoagulant Therapy Versus Antiplatelet Therapy in Acute Ischemic Stroke Patients with Atrial Fibrillation

The efficacy and safety of anticoagulant therapy in patients with acute ischemic stroke (AIS) and atrial fibrillation (AF) remain uncertain. This study enrolled 431 AIS and AF patients from Nanjing Drum Tower Hospital between January 2019 and December 2021 and followed for 365 days to determine the associations between anticoagulants and clinical outcomes by assessing modified Rankin Scale (mRS) score, recurrent ischemic stroke/systemic embolism (IS/SE), all-cause mortality, intracranial hemorrhage (ICH) and major bleeding. Final analysis included 400 eligible patients and divided them into antiplatelet group (n  =  191) and anticoagulant group (n  =  209). Anticoagulant therapy was associated with excellent (mRS 0-1; adjusted odds ratio (aOR), 2.63; 95% confidence interval (CI), 1.61-4.30) and favorable functional outcomes (mRS 0-2; aOR, 2.82; 95% CI, 1.69-4.70) and lower risk of all-cause mortality (adjusted hazard ratio (aHR), 0.35; 95% CI, 0.21-0.57), ICH (aHR, 0.45; 95% CI, 0.23-0.87) and major bleeding (aHR, 0.51; 95% CI, 0.28-0.94), without increasing the risk of recurrent IS/SE (aHR, 0.75; 95% CI, 0.45-1.24). In conclusion, anticoagulant therapy may be a more effective and safer option than antiplatelet therapy for AIS patients with AF.

Intravenous thrombolysis with 0.65 mg/kg r-tPA may be optimal for Chinese mild-to-moderate stroke

Background

Intravenous recombinant tissue plasminogen activator (r-tPA) with 0.9 mg/kg is the standard treatment for acute ischemic stroke, but it remains unclear whether it is optimal for all patients. We aimed to determine the optimal dose of r-tPA for Chinese stroke based on the data from the INTRECIS study.

Methods

From the INTRECIS cohort, patients receiving intravenous r-tPA within 4.5 h of onset were included. According to r-tPA dose, patients were assigned into seven groups (from 0.60 to 0.90 mg/kg). The primary outcomes were the proportion of excellent functional outcomes and symptomatic intracranial hemorrhage.

Results

Overall, 2,666 patients were included: 156 in 0.60 mg/kg group, 117 in 0.65 mg/kg group, 127 in 0.70 mg/kg group, 188 in 0.75 mg/kg group, 154 in 0.80 mg/kg group, 359 in 0.85 mg/kg group, and 1,565 in 0.90 mg/kg group. After adjustment for baseline characteristics, only 0.65 mg/kg group had significantly higher proportion of excellent functional outcome than 0.90 mg/kg group (79.5 vs. 71.4%, odds ratio = 1.833, 95% CI = 1.006–3.341, adjusted p = 0.048). The subgroup analysis showed no evidence of differences in the odds of having a primary outcome between the two groups by age, admission NIHSS, onset to thrombolysis time, and TOAST classification. There was no significant difference in symptomatic intracranial hemorrhage between groups.

Conclusion

Our study presented the first evidence that intravenous thrombolysis with 0.65 mg/kg r-tPA may be optimal for Chinese mild-to-moderate stroke.

Registration

https://www.clinicaltrials.gov, identifier: NCT 02854592.

David G. Sherman Lecture Award: 15-Year Experience of the Nationwide Multicenter Stroke Registry in Korea

The expected growth of stroke burden in Korea in early 2000s led to the initiation of a government-funded clinical research project with the goal of development and implementation of national stroke guidelines. The CRCS-K (Clinical Research Collaboration for Stroke in Korea) began as a part of this project. For stroke epidemiology and quality of care research, the CRCS-K developed a multicenter, prospective, stroke registry and began collection of data in 2008. Now, about 100 000 cases have been registered at 17 university hospitals or regional stroke centers and about 200 articles have been published based on the registry experience. The analysis of the 10-year secular trends showed overall improvement of stroke care and outcomes and areas for improvement. This large-scale, high-quality dataset provides opportunities to explore and compare treatment disparities using the comparative effectiveness research methods, design and conduct a registry-based randomized clinical trial, connect the registry data with other data sources including the national claims data and neuroimaging or genetic data, and collaborate with other international researchers. An international stroke registry consortium may be a viable future direction.

Low-dose alteplase for the management of acute ischemic stroke in South Asians: A systematic review on cost, efficacy and safety

INTRODUCTION

South Asia is responsible for more than 40% of the stroke burden and stroke mortality in the developing world. South Asia, which is home to one-fourth of the world's population, is the most densely populated and one of the poorest regions. The majority of patients in this region are unable to afford intravenous thrombolysis (IVT) for acute ischemic stroke (AIS). If low-dose alteplase proves effective and safe in South Asians, it may be a more cost-effective treatment option.

METHODS

The study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-Analyses) guideline. Researchers searched PubMed, EMBASE, and Google Scholar for English literature from 2005 to 2021. END, ENI, good functional outcome, SICH, and all-cause mortality were used to assess efficacy and safety.

RESULTS

In the low-dose alteplase treated patients, different studies reported 32 to 57% ENI 24 h after IVT, and 7% to 9.7% END. At 3 months follow-up, good functional outcome was achieved by 48%-76.92% of low-dose alteplase treated patients. SICH rates ranged from 0% to 16.6% across studies. Asymptomatic ICH occurred in 5-14% of patients. The mortality rate in all included studies varied from none to 25%.

CONCLUSION

Our systematic review demonstrates that the use of low-dose alteplase for AIS in the South Asians offer comparable efficacy and reduced risk of SICH at a significantly lower cost than standard alteplase dose. Future well-randomized clinical trials are necessary to validate the findings of our study.

Different Doses of Intravenous Tissue-Type Plasminogen Activator for Acute Ischemic Stroke: A Network Meta-Analysis

Background

This study aims to assess the efficacy and safety of different doses of intravenous tissue-type plasminogen activator (tPA) for acute ischemic stroke (AIS) by adopting a network meta-analysis (NMA).

Methods

Studies comparing different doses of tPA in AIS were identified by retrieving electronic databases. NMAs of outcome measures included favorable functional outcome with a modified Rankin scale score (mRS) of 0 or 1 at 3 months after treatment (3M-FF), the functional independence with a mRS of 0, 1, or 2 at 3 months (3M-FI), symptomatic intracranial hemorrhage (sICH) and 3-month all-cause mortality (3M-M). Symptomatic intracranial hemorrhage (sICH) and 3-month all-cause mortality (3M-M) were assessed. Probability-based ranking and surface under cumulative ranking (SUCRA) were performed to identify the best dose of tPA. Inconsistency was evaluated by node-splitting analysis and a loop-specific approach. Publication bias was analyzed by funnel plots.

Results

A total of 14 studies were included in the quantitative synthesis. The NMA results revealed no difference among low (<0.7 mg/kg), moderate (0.8 mg/kg), and standard (0.9 mg/kg) doses of tPA with regard to efficacy and safety. The SUCRAs of 3M-FF and 3M-FI showed that the standard dose ranked first, the moderate dose ranked second, and the low dose ranked third. The SUCRA of sICH showed that the standard dose ranked first (78.1%), the low dose ranked second (61.0%), and the moderate dose ranked third (11.0%). The SUCRAs of 3-month mortality showed that the standard dose ranked first (73.2%), the moderate dose ranked second (40.8%), and the low dose ranked third (36.1%). No significant inconsistency was shown by node-splitting analysis and no publication bias was shown in funnel plots.

Conclusion

Lower dose tPA was comparable to the standard dose with regard to efficacy and safety. Based on the SUCRA results and American Heart Association/American Stroke Association (AHA/ASA) guidelines, the standard dose was still the optimal selection for AIS.

Outcome of Delayed Administration of Alteplase in a Resource-Poor Area: A Case Report

An acute ischemic stroke, though carrying the risk of debilitating complications, is a preventable and treatable disease. Thrombolysis and endovascular thrombectomy are important components of its management. However, various challenges in resource-poor countries like Nigeria and other developing nations pose a great limitation in the timely intervention of ischemic stroke treatment. The challenges include late presentation, poor awareness of stroke symptoms even among health care workers, poor ambulance service/transportation network, intra-hospital delay, particularly in neuroimaging, and the unavailability of tissue plasminogen activator (alteplase/tenecteplase). We report a 32-year-old African man with an antecedent history of suspected migraine headaches with aura and a family history of hypertension and stroke, admitted 7½ hours after onset of stroke symptoms, scoring 13 on the National Institutes of Health Stroke Scale (NIHSS) with Medical Research Council (MRC) muscle power grades 1 and 3 on the right upper and lower extremities, respectively. Urgent non-contrast brain CT revealed only a hyperdense sign in the left middle cerebral artery (MCA). Intravenous tissue plasminogen activator (tPA) was administered at a lower dose of 0.6 mg/kg, 15½ hours after symptom onset, and a CT angiogram done 24 hours post-thrombolysis showed partial recanalization of the M1 segment of the MCA and intermediate collateral supply (Alberta stroke program early CT {ASPECT} score: 6). By the third day of admission, he had made a significant clinical improvement and was discharged home able to walk unsupported on the fourth day.

Controversies in cerebrovascular disease: high or low doses of recombinant tissue plasminogen activator to treat acute stroke? A literature review

INTRODUCTION

The use of low doses of recombinant tissue plasminogen activator (rt-PA) was initially proposed in Asian countries in response to racial peculiarities related to the functionality of fibrinogen and coagulation factors that potentially increased the risk of intracerebral haemorrhage, and with a view to saving costs. In view of the controversy over the use of rt-PA below the standard dose, we conducted a literature review of studies promoting the use of low doses or comparing different doses of rt-PA.

DEVELOPMENT

We reviewed 198 abstracts related to the search terms and the full texts of 52 studies published in the last 30 years. We finally included 13 randomised clinical trials aiming to determine the efficacy and safety of the use of rt-PA at different doses in acute stroke, 14 observational cohort studies, 5 meta-analyses, and 3 systematic reviews.

CONCLUSIONS

There is insufficient evidence to classify low doses of rt-PA as superior or at least not inferior to the standard treatment in the management of acute stroke in western populations. More clinical trials are required to determine whether the use of low doses is beneficial in patients with relative contraindications for thrombolytic therapy or other particular circumstances that may increase the risk of intracerebral haemorrhage.

Effectiveness of Standard-Dose vs. Low-Dose Alteplase for Acute Ischemic Stroke Within 3-4.5 h

Background

The efficacy and safety of intravenous alteplase administered 3–4.5 h after acute ischemic stroke have been demonstrated. However, whether responses differ between low-dose and standard-dose alteplase during this time window and whether certain subgroups benefit more remain unknown.

Patients and Methods

The current analysis was based on a multicenter matched-cohort study conducted in Taiwan. The treatment group comprised 378 patients receiving intravenous alteplase 3–4.5 h after stroke onset, and the control group comprised 378 age- and sex-matched patients who did not receive alteplase treatment during the same period. Standard- and low-dose alteplase was administered to patients at the physician's discretion.

Results

Overall, patients receiving alteplase exhibited more favorable outcomes than did controls [34.0 vs. 22.7%; odds ratio (OR): 1.75, 95% confidence interval (CI): 1.27–1.42], and the effectiveness was consistent in all subgroups. Although patients in the standard-dose group (n = 182) were younger than those in the low-dose (n = 192) group, the proportions of patients with favorable outcomes (36.3 vs. 31.8%; OR: 1.22, 95% CI: 0.80–1.88) and symptomatic hemorrhage (2.8 vs 4.2%; OR: 0.65, 95% CI: 0.21–2.02) were consistently comparable in a covariate-adjusted model and an age-matched cohort. In the subgroup analysis, patients with cardioembolism, atrial fibrillation, and hypercholesterolemia were more likely to achieve favorable outcomes after receiving standard-dose than low-dose alteplase.

Conclusion

In the 3–4.5 h time window, the effectiveness and safety of standard-dose and low-dose alteplase may be comparable. A standard dose may be selected for patients with cardioembolism, atrial fibrillation, or hypercholesterolemia.

Controversies in cerebrovascular disease: High or low doses of recombinant tissue plasminogen activator to treat acute stroke? A literature review

INTRODUCTION

The use of low doses of recombinant tissue plasminogen activator (rt-PA) was initially proposed in Asian countries in response to racial peculiarities related to the functionality of fibrinogen and coagulation factors that potentially increased the risk of intracerebral haemorrhage, and with a view to saving costs. In view of the controversy over the use of rt-PA below the standard dose, we conducted a literature review of studies promoting the use of low doses or comparing different doses of rt-PA.

DEVELOPMENT

We reviewed 198 abstracts related to the search terms and the full texts of 52 studies published in the last 30 years. We finally included 13 randomised clinical trials aiming to determine the efficacy and safety of the use of rt-PA at different doses in acute stroke, 14 observational cohort studies, 5 meta-analyses, and 3 systematic reviews.

CONCLUSIONS

There is insufficient evidence to classify low doses of rt-PA as superior or at least not inferior to the standard treatment in the management of acute stroke in western populations. More clinical trials are required to determine whether the use of low doses is beneficial in patients with relative contraindications for thrombolytic therapy or other particular circumstances that may increase the risk of intracerebral haemorrhage.

Safety and efficacy of tenecteplase versus alteplase in patients with acute ischaemic stroke (TRACE): a multicentre, randomised, open label, blinded-endpoint (PROBE) controlled phase II study

Background

Tenecteplase (TNK) possesses several pharmacological characteristics superior to conventional alteplase (rt-PA), with well-established safety and efficacy profile in Caucasians. There exists controversy over the optimal dose of intravenous rt-PA for East Asians with acute ischaemic stroke (AIS). Current study aimed to determine the safety dose range of recombinant human TNK tissue-type plasminogen activator (rhTNK-tPA) for patients with AIS in China.

Methods

This multicentre, prospective, randomised, open-label, blinded end-point, phase II study compared three tiers of 0.1, 0.25, 0.32 mg/kg rhTNK-tPA (to a maximum of 40 mg) with standard 0.9 mg/kg rt-PA (to a maximum of 90 mg) in patients who were eligible for intravenous thrombolysis. The safety outcome were symptomatic intracranial haemorrhage (sICH) within 36 hours.

Results

Between May 2018 and February 2020, 240 patients were randomly assigned to four group, 4 of whom did not receive study treatment. The intention-to-treat analysis included 236 patients. There was no difference in the improvement on National Institutes of Health Stroke Scale at day 14 in the 3 tiers and control group (63.3%, 77.2%, 66.7% vs 62.7%). The number of sICH was 3 of 60 (5.0%) in the 0.1 mg/kg group, none in the 0.25 mg/kg group, 2 of 60 (3.3%) in the 0.32 mg/kg group and 1 (1.7%) of 59 in the rt-PA group. There were no significant between-group differences in severe adverse events.

Conclusions

Similar to the Caucasians, rhTNK-tPA was well tolerated in Chinese patients with AIS at all doses administered within 3 hours of symptom onset. The dose-efficacy profile of rhTNK-tPA needs to be established with future investigations.

Trial registration number

NCT04676659.

Low versus standard dose intravenous alteplase in the treatment of acute ischemic stroke in Egyptian patients

Objectives:

To assess low dose altepase outcome and safety in comparison with a standard-dose regimen for acute ischemic stroke treatment in Egyptian patients.

Materials:

An observational prospective cohort non-randomized single blinded study was carried out during the period from November 2017 to December 2018. Eighty Egyptian acute ischemic stroke patients, all eligible for intravenous alteplase, were subdivided into 2 groups (40 patients in each group). Patients were thrombolysed at a dose of 0.6 mg/kg in the first group and 0.9 mg/kg in the second group. Both groups were compared in regard to safety and outcome. Safety was expressed by the rate of symptomatic intracranial hemorrhage (SICH) and 3 months mortality, while outcome was expressed by favorable outcomes at three months (modified Rankin Scale [mRS] of 0 to 2).

Results:

In the first group, 69.2% (n=27) achieved favorable outcomes at 90 days compared with 64.1% (n=25) in the second group (p=0.631). Ninety-day mortality was 5% (n=2) in the first group versus 2.5% (n=1) in the second group (p=0.556). Symptomatic intracranial hemorrhage was noted in 3 patients in the second group and zero patients in the first group (p=0.077).

Conclusion:

Low-dose alteplase could be a practical alternative for Egyptian populations with acute ischemic stroke especially in 3 to 4.5 hours window.

European Stroke Organisation (ESO) guidelines on intravenous thrombolysis for acute ischaemic stroke

Intravenous thrombolysis is the only approved systemic reperfusion treatment for patients with acute ischaemic stroke. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions with regard to intravenous thrombolysis for acute ischaemic stroke. These guidelines were developed based on the ESO standard operating procedure and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote recommendations. Expert consensus statements were provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found high quality evidence to recommend intravenous thrombolysis with alteplase to improve functional outcome in patients with acute ischemic stroke within 4.5 h after symptom onset. We also found high quality evidence to recommend intravenous thrombolysis with alteplase in patients with acute ischaemic stroke on awakening from sleep, who were last seen well more than 4.5 h earlier, who have MRI DWI-FLAIR mismatch, and for whom mechanical thrombectomy is not planned. These guidelines provide further recommendations regarding patient subgroups, late time windows, imaging selection strategies, relative and absolute contraindications to alteplase, and tenecteplase. Intravenous thrombolysis remains a cornerstone of acute stroke management. Appropriate patient selection and timely treatment are crucial. Further randomized controlled clinical trials are needed to inform clinical decision-making with regard to tenecteplase and the use of intravenous thrombolysis before mechanical thrombectomy in patients with large vessel occlusion.

Impact of estimated-weight-base dose of alteplase in acute stroke treatment on clinical outcome

Dosing of recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke treatment is often based on estimated body weight (BW) worldwide in routine clinical practice due to infeasible of accurate BW measurement. The aim of our study is to explore the impact of estimated BW when dosing rt-PA in acute ischemic stroke treatment on clinical outcome. Between January 2013 to May 2018, 126 acute ischemic stroke patients received intravenous rt-PA treatment based on estimated BW dosage were recruited. All patients had actual BW measured in ward after treatment. Based on the dosage of rt-PA given, patients were categorized into three groups, standard dose (0.8-1.0 mg/kg), overdose (>1.0 mg/kg), and underdose (<0.8 mg/kg). Among all 126 patients, 101 (80.2%) patients were treated with standard dose, 12 (9.5%) patients with overdose, and 13 (10.3%) patients with underdose of rt-PA respectively. There was no significant difference between demographic characteristics, pre-morbid risk factors, National Institutes of Health Stroke Scale (NIHSS) score at 24 h, NIHSS score at discharge, modified Rankin scale (mRS) within 0 to 2 in discharge or in 3 months after the event within the three groups. There was also no significant difference in hemorrhagic transformation and symptomatic intracranial hemorrhage (SICH). In conclusion, calculation of the dose of rt-PA based upon the estimated BW to treat acute ischemic stroke patients had no negative impact on the clinical outcome in our study.

Worse prognosis in women, compared with men, after thrombolysis: An individual patient data pooling study of Asian acute stroke registries

BACKGROUND AND PURPOSE

To examine sex differences in disease profiles and short-term outcomes after acute ischemic stroke treated with recombinant tissue plasminogen activator.

METHODS

Eight national and regional stroke registries contributed individual participant data from mainland China, Japan, Philippines, Singapore, South Korea and Taiwan in 2005-2018. The primary outcome was ordinal-modified Rankin scale at 90 days. Key safety outcome was symptomatic intracerebral hemorrhage (sICH).

RESULTS

Of 4453 patients included in the analyses, 1692 (36.3%) were women who were older, more likely to have a more severe neurological deficit, history of hypertension and atrial fibrillation, and a cardioembolic stroke compared to men. Women were more likely than men to have unfavorable shift of modified Rankin scale (fully adjusted odds ratio) (women vs. men) 1.14, 95% confidence interval 1.02-1.28). There was no significant sex difference for death 1.05 (0.84-1.31) or sICH (1.17, 0.89-1.54). Women were more likely to have unfavorable functional outcome with increasing age (P = 0.022 for interaction). In the age groups 70-80 and ≥80 years, women had a worse functional outcome compared to men (1.22, 1.02-1.47 and 1.43, and 1.06-1.92, respectively).

CONCLUSION

In this pooled data from Asian acute stroke registries, women had poorer prognosis than men after receiving recombinant tissue plasminogen activator for acute ischemic stroke, which worsened with age. Women older than 70 appear to have a worse outcome than men which could be explained by greater stroke severity, more AF, and cardioembolic stroke.

Individualized intravenous thrombolytic strategy for acute ischemic stroke with large vessel occlusion on the era of mechanical thrombectomy: cases report

Intravenous thrombolysis for acute ischemic stroke within 4.5 h after the onset of symptoms has become a standard therapy that is recommended by many trials and clinical guidelines. As on the era of mechanical thrombectomy for acute ischemic stroke with large vessel occlusions, whether intravenous thrombolysis (IVT) is still necessary, and how to choose the optimal dose are still controversy. Here, we reported two cases of acute ischemic stroke with large vessel occlusions that both achieved complete recanalization after IVT. Then, IVT was terminated in advance, and dynamic surveillance by DSA was performed to achieve individual treatment. However, both of the cases presented with hemorrhagic transformation. We analyzed the probable reasons and put forward thoughts from ourselves.

The Impact of Loading Dose on Outcome in Stroke Patients Receiving Low-Dose Tissue Plasminogen Activator Thrombolytic Therapy

Background

Intravenous tissue plasminogen activator (tPA) (0.9 mg/kg, maximum 90 mg) with a bolus of 10% of the total dose given within 1–2 mins is the standard therapy for patients receiving thrombolytic therapy. Low-dose (0.6 mg/kg) tPA is also approved for thrombolytic therapy for ischemic stroke patients. Low-dose tPA is associated with a low bolus dose. It is unknown whether increasing the bolus dose in patients receiving low-dose tPA thrombolysis may improve outcomes or increase the risk of hemorrhagic transformation (HT).

Aim

This study investigated the impact of the bolus dose on the outcome in ischemic stroke patients receiving low-dose tPA thrombolytic therapy.

Methods

In this retrospective, observational study, we enrolled 214 ischemic stroke patients receiving low-dose tPA thrombolytic therapy. Of these 214 patients, 107 patients received 10% of the total dose as a bolus dose, and 107 patients received 15% of the total dose as a bolus dose. The National Institutes of Health Stroke Score (NIHSS) were evaluated before tPA infusion, 24 h after thrombolytic therapy, and at discharge. Stroke severity was categorized as mild (0–5), moderate (6–14), severe (15–24), or very severe (≥25). Neurological improvement (NI) was defined as an improvement of 6 or more points in the NIHSS, and no response (NR) was defined as an increase in the NIHSS of ≤4 points or a decrease ≤6 points. Neurological deterioration (ND) was defined as an increase in the NIHSS >4 points. A good outcome was defined as a modified Ranking Score (mRS) of 0 or 1. We compared the NI, NR, and ND rates at 24 hrs after thrombolytic therapy and discharge between the 15% and 10% bolus dose groups.

Results

In patients with mild and moderate stroke, there was no significant difference in the NI, NR, ND, and HT rates and 6-month outcomes between the 15% and 10% bolus groups. In patients with severe and very severe stroke, outcomes at 6 months were significantly better in the 15% bolus group than in the 10% bolus group. The factors affecting the outcomes of severe and very severe stroke patients are hypertension and bolus dose.

Conclusion

In severe and very severe stroke patients receiving low-dose tPA thrombolytic therapy, a bolus dose of 15% of the total dose can improve outcomes.

Intravenous Thrombolysis Administration 3-4.5 h After Acute Ischemic Stroke: A Retrospective, Multicenter Study

Background and Objectives: Intravenous recombinant tissue plasminogen activator (rt-PA) has been approved for acute ischemic stroke (AIS) within 3 h after onset and the treatment was then extended to 4.5 h. However, the Food and Drug Administration did not approve the indication in the expanded time window. This retrospective, matched cohort study aims to investigate the effectiveness and safety of rt-PA in AIS at 3-4.5 h after onset. Materials and Methods: The treatment group included AIS patients receiving rt-PA at 3-4.5 h after onset, otherwise complying with the regulation, in the stroke registries in 16 hospitals between 2008 and 2017. The control group included age- and sex-matched patients not receiving intravenous thrombolysis from the same registries, excluding those with contraindications. The primary outcome was modified Rankin Scale (mRS) 0-1 at day 90. The safety outcomes were any intracerebral hemorrhage (ICH), early neurological deterioration and 3-month mortality. Results: Each group had 374 patients. There were 34.0% of patients with 3-month mRS 0-1 in the treatment group vs. 22.7% in the control group with an odds ratio of 1.75 (95% confidence intervals, 1.27 to 2.42, P = 0.001). There was no difference in symptomatic ICH, early neurological deterioration and 3-month mortality rates between two groups. The 3-month mRS and symptomatic ICH did not differ significantly in patients receiving standard dose or low dose of rt-PA. Conclusions: Our results support the prescription of rt-PA in AIS patients 3-4.5 h after onset as an effective and tolerable treatment in their functional recovery.

Who will benefit more from low-dose alteplase in acute ischemic stroke?

OBJECTIVES

Controversy persists over the benefits of low-dose versus standard-dose intravenous alteplase for the treatment of acute ischemic stroke. We sought to determine individual patient factors that contribute to the risk-benefit balance of low-dose alteplase treatment.

METHODS

Observational study using data from the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED), an international, randomized, open-label, blinded-endpoint trial that assessed low-dose (0.6 mg/kg) versus standard-dose (0.9 mg/kg) intravenous alteplase in acute ischemic stroke patients. Logistic regression models were used to estimate the benefit of good functional outcome (scores 0 or 1 on the modified Rankin scale at 90 days) and risk (symptomatic intracerebral hemorrhage), under both regimens for individual patients. The net advantage for low-dose, relative to standard-dose, alteplase was calculated by dividing excess benefit by excess risk according to a combination of patient characteristics. The algorithms were externally validated in a nationwide acute stroke registry database in South Korea.

RESULTS

Patients with an estimated net advantage from low-dose alteplase, compared with without, were younger (mean age of 66 vs. 75 years), had lower systolic blood pressure (148 vs. 160 mm Hg), lower National Institute of Health Stroke Scale score (median of 8 vs. 16), and no atrial fibrillation (10.3% vs. 97.4%), diabetes mellitus (19.2% vs. 22.4%), or premorbid symptoms (defined by modified Rankin scale = 1) (16.3% vs. 37.8%).

CONCLUSION

Use of low-dose alteplase may be preferable in acute ischemic stroke patients with a combination of favorable characteristics, including younger age, lower systolic blood pressure, mild neurological impairment, and no atrial fibrillation, diabetes mellitus, or premorbid symptoms.

Low-dose versus standard-dose alteplase in acute ischemic stroke in Asian stroke registries: an individual patient data pooling study

OBJECTIVE

To investigate the comparative efficacy and safety of the low-dose versus standard-dose alteplase using real-world acute stroke registry data from Asian countries.

METHODS

Individual participant data were obtained from nine acute stroke registries from China, Japan, Philippines, Singapore, South Korea, and Taiwan between 2005 and 2018. Inverse probability of treatment weight was used to remove baseline imbalances between those receiving low-dose versus standard-dose alteplase. The primary outcome was death or disability defined by modified Rankin Scale scores of 2 to 6 at 90 days. Secondary outcomes were symptomatic intracerebral hemorrhage and death. Generalized linear mixed models with the individual registry as a random intercept were performed to determine associations of treatment with low-dose alteplase and outcomes.

RESULTS

Of the 6250 patients (mean age 66 years, 36% women) included in these analyses, 1610 (24%) were treated with low-dose intravenous alteplase. Clinical outcomes for low-dose alteplase were not significantly different to those for standard-dose alteplase, adjusted odds ratios for death or disability: 1.00 (0.85-1.19) and symptomatic intracerebral hemorrhage 0.87 (0.63-1.19), except for lower death with borderline significance, 0.77 (0.59-1.01).

CONCLUSIONS

The present analyses of real-world Asian acute stroke registry data suggest that low-dose intravenous alteplase has overall comparable efficacy for functional recovery and greater potential safety in terms of reduced mortality, to standard-dose alteplase for the treatment of acute ischemic stroke.

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time

Thrombolytic therapy is one of the medical procedures in the treatment of acute ischaemic stroke (AIS), whereby the tissue plasminogen activator (tPA) is intravenously administered to dissolve the obstructive blood clot. The treatment of AIS by thrombolysis can sometimes be ineffective and it can cause serious complications, such as intracranial haemorrhage (ICH). In this study, we propose an efficient mathematical modelling approach that can be used to evaluate the therapeutic efficacy and safety of thrombolysis in various clinically relevant scenarios. Our model combines the pharmacokinetics and pharmacodynamics of tPA with local clot lysis dynamics. By varying the drug dose, bolus-infusion delay time, and bolus-infusion ratio, with the FDA approved dosing protocol serving as a reference, we have used the model to simulate 13 dose regimens. Simulation results are compared for temporal concentrations of fibrinolytic proteins in plasma and the time that is taken to achieve recanalisation. Our results show that high infusion rates can cause the rapid degradation of plasma fibrinogen, indicative of increased risk for ICH, but they do not necessarily lead to fast recanalisation. In addition, a bolus-infusion delay results in an immediate drop in plasma tPA concentration, which prolongs the time to achieve recanalisation. Therefore, an optimal administration regimen should be sought by keeping the tPA level sufficiently high throughout the treatment and maximising the lysis rate while also limiting the degradation of fibrinogen in systemic plasma. This can be achieved through model-based optimisation in the future.

Low-dose rt-PA may not decrease the incidence of symptomatic intracranial haemorrhage in patients with high risk of symptomatic intracranial haemorrhage

BACKGROUND

Recombinant tissue plasminogen activator (rt-PA) has been used as the standard treatment for acute ischemic stroke (AIS). The following study investigates whether low-dose rt-PA can decrease the incidence of symptomatic intracranial haemorrhage (sICH) in AIS patients with high-risk sICH compared to standard-dose rt-PA.

MATERIALS AND METHODS

Data from the Thrombolysis Implementation and Monitor of Acute Ischemic Stroke in China (TIMS-China) studies were assessed to explore risk factors for sICH after intravenous thrombolysis. For high-risk sICH patients (age ≧70 years old, or with diabetes, or serum glucose on admission >9.0 mmol/L, or NIHSS on admission>20, or with cardioembolism), standard-dose rt-PA (0.85 to 0.95 mg/kg) and low- dose rt-PA (0.5 to 0.7 mg/kg) were compared. Primary outcome measure was the incidence of sICH, and the secondary outcome measures were 7-day mortality and 90-day functional independence outcome (modified Rankin scale, 0-2).

RESULTS

A total of 554 patients were enrolled (60 cases for low dose, and 494 cases for standard dose). Median rt-PA doses were 0.63 and 0.90 mg, respectively. After adjustment for the baseline variables, low-dose rt-PA did not decrease the incidence of sICH (per SITS-MOST criteria, 3.33% versus 2.23%, P = 0.3467) compared to low dose. The low-dose group revealed less functional independence outcomes (modified Rankin scale, 0-2) compared to standard-dose group (36.67% versus 52.43%; odds ratio = 0.49; p = 0.0204) at 90 days.

CONCLUSIONS

Our study suggests that low-dose intravenous rt-PA for high-risk sICH stroke in Chinese patients may not decrease the incidence of sICH, and concomitant with a poor outcome compared to standard-dose rt-PA.

ABBREVIATIONS

rt-PA: recombinant tissue plasminogen activator; AIS: acute ischemic stroke; sICH: symptomatic intracranial haemorrhage.

Predictors of functional outcome in patients with stroke thrombolysis in a tertiary hospital in Malaysia

INTRODUCTION

Intravenous (IV) thrombolysis with alteplase (rt-PA) is effective in ischaemic stroke. The primary objective was to evaluate predictors of functional outcome in acute ischaemic stroke (AIS) patients treated with IV rt-PA. The secondary objective was to assess the outcome with the modified Rankin scale (mRS). We also examined the predictive value of the Totaled Health Risks in Vascular Events (THRIVE) score.

METHODS

AIS patients treated with IV rt-PA from February 2012 to August 2016 were recruited. Demographic data, National Institutes of Health Stroke Scale (NIHSS) scores, timing and neuroradiological findings were recorded. Patients received a dose of 0.9 mg/kg IV rt-PA within 4.5 hours of symptom onset. mRS score was evaluated at discharge and three months, and good and poor clinical outcomes were defined as scores of 0-2 and 3-6, respectively. Baseline THRIVE scores were assessed.

RESULTS

36 patients received IV rt-PA. 20 (55.6%) patients had an mRS score of 0-2 at three months. Based on THRIVE score, 86.1% had a good or moderately good prognosis. On univariate analysis, poor outcome was associated with NIHSS score before rt-PA (p = 0.03), THRIVE score (p = 0.02), stroke subtype (p = 0.049) and diabetes mellitus (DM; p = 0.06). Multiple logistic regression showed that outcome was significantly associated with NIHSS score before rt-PA (p = 0.032) and DM (p = 0.010).

CONCLUSION

Our newly developed Malaysian IV rt-PA service is safe, with similar outcomes to the published literature. Functional outcome after thrombolysis was associated with baseline NIHSS score and DM.

Acute Treatment of Stroke (Except Thrombectomy)

PURPOSE OF REVIEW

The management of patients with acute stroke has been revolutionized in recent years with the advent of new effective treatments. In this rapidly evolving field, we provide an update on the management of acute stroke excluding thrombectomy, looking to recent, ongoing, and future trials.

RECENT FINDINGS

Large definitive trials have provided insight into acute stroke care including broadening the therapeutic window for thrombolysis, alternatives to standard dose alteplase, the use of dual antiplatelet therapy early after minor ischemic stroke, and treating elevated blood pressure in intracerebral hemorrhage. Further ongoing and future trials are eagerly awaited in this ever-expanding area. Although definitive trials have led to improvements in acute stroke care, there remains a need for further research to improve our understanding of pathophysiological mechanisms underlying different stroke types with the potential for treatments to be tailored to the individual.

Understanding haemorrhagic risk following thrombolytic therapy in patients with intermediate-risk and high-risk pulmonary embolism: a hypothesis paper

While systemic intravenous thrombolysis decreases mortality in patients with high-risk pulmonary embolism (PE), it clearly increases haemorrhagic risk. There are many contraindications to thrombolysis, and efforts should aim at selecting those patients who will benefit most, without suffering complications. The current review summarises the evidence for the use of thrombolytic therapy in PE. It clarifies the pathophysiological mechanisms in PE and acute cor pulmonale that increase the risk of bleeding following thrombolysis. It discusses future management challenges, namely tailored drug administration, new treatment monitoring techniques and catheter-directed thrombolysis.

Current status of intravenous tissue plasminogen activator dosage for acute ischaemic stroke: an updated systematic review

The optimal dose of recombinant tissue plasminogen activator (rtPA) for acute ischaemic stroke (AIS) remains controversial, especially in Asian countries. We aimed to update the evidence regarding the use of low-dose versus standard-dose rtPA. We performed a systematic literature search across MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO and Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception to 22 August 2016 to identify all related studies. The outcomes were death or disability (defined by modified Rankin Scale 2–6), death, and symptomatic intracerebral haemorrhage (sICH). Where possible, data were pooled for meta-analysis with ORs and corresponding 95% CIs by means of random-effects or fixed-effects meta-analysis. We included 26 observational studies and 1 randomised controlled trial with a total of 23 210 patients. Variable doses of rtPA were used for thrombolysis of AIS in Asia. Meta-analysis shows that low-dose rtPA was not associated with increased risk of death or disability (OR 1.13, 95% CI 0.95 to 1.33), or death (OR 0.86, 95% CI 0.74 to 1.01), or decreased risk of sICH (OR 1.06, 95% CI 0.65 to 1.72). The results remained consistent when sensitivity analyses were performed including only low-dose and standard-dose rtPA or only Asian studies. Our review shows small difference between the outcomes or the risk profile in the studies using low-dose and/or standard-dose rtPA for AIS. Low-dose rtPA was not associated with lower risk of death or disability, death alone, or sICH.

Comparative Analysis on Low- and Standard-Dose Regimes of Alteplase Thrombolytic Therapy for Acute Ischemic Stroke: Efficacy and Safety

Objective: This study analyzed the efficacy and safety of low-dose and standard-dose alteplase intravenous thrombolytic therapy for acute ischemic stroke (AIS). Methods: Patients with AIS who underwent intravenous alteplase thrombolysis from July 2012 to December 2016 were retrospectively analyzed and correspondingly divided into low-dose (0.6–0.89 mg/kg) group and standard-dose group (0.9 mg/kg) according to alteplase dosage. The clinical outcome was evaluated by modified Rankin Scale (mRS) at 90 days after onset. The safety index was the mortality at 90 days after onset and the incidence of symptomatic intracranial hemorrhage (SICH) within 7 days. Results: A total of 1,486 patients were included (1,115 cases in low-dose group and 371 cases in standard-dose group). There were no significant differences in baseline data between the 2 groups. As mRS, good outcome rate as well as mortality rate in both groups had no significant difference (36.1 vs. 37.6%; χ2 = 10.882, p = 0.890; 5.5 vs. 7.3%; χ2 = 2.163, p = 0.076), but the incidence of SICH in low-dose group was significantly lower than that of the standard-dose group (2.2 vs. 5.9%; χ2 = 3.157, p = 0.001). Conclusion: The efficacy of low-dose alteplase intravenous thrombolytic therapy for AIS was equivalent to the standard-dose regimen but with higher safety.

Low- versus Standard-Dose Intravenous Tissue-Type Plasminogen Activator for Acute Ischemic Stroke: An Updated Meta-Analysis

BACKGROUND

We performed a meta-analysis to compare the efficacy and safety between low- and standard-dose intravenous (IV) tissue-type plasminogen activator (tPA) for acute ischemic stroke (AIS) patients within 4.5 hours of symptom onset.

METHODS

We searched PubMed and EMBASE for relevant studies from inception to June1, 2017. Cohort or randomized controlled studies for AIS within 4.5 hours of symptom onset with comparison between low-dose and standard-dose tPA were included. The primary efficacy end point was favorable functional outcome (modified Rankin scale scores [mRS] of 0-1) at 90 days. The primary safety end point was the incidence rate of symptomatic intracerebral hemorrhage (sICH). The secondary end points were independent functional outcome (mRS scores of 0-2) and mortality.

RESULTS

A total of 11 studies were pooled in this meta-analysis. The low-dose strategy appeared to be as effective as standard-dose tPA (43.4% versus 45.4%; odds ratio [OR] = 0.93, 95% confidence interval [CI]: 0.78-1.10; P = .38) in primary efficacy outcome. The secondary efficacy outcome produced similar results (57.3% versus 57.0%; OR = 0.95, 95% CI: 0.86-1.05; P= .33). There was no evidence of statistical difference for sICH (4.2% versus 4.9%; OR = 1.02 [0.66-1.55]; P = .94) and mortality (9.0% versus 10.6%; OR = 0.99 [0.74-1.31]; P = .92) at 90 days between low- and standard-dose therapy. In a subgroup analysis by ethnicity, there was no significant difference between patients of Asian and non-Asian descent for any of the end points.

CONCLUSIONS

This study showed that AIS patients receiving low-dose IV-tPA had comparably efficacy and safety to those receiving standard-dose IV-tPA. However, the effect is especially pronounced within the Asian population, which limits the generalizability of these results.

Low-Dose vs Standard-Dose Alteplase for Patients With Acute Ischemic Stroke: Secondary Analysis of the ENCHANTED Randomized Clinical Trial

Importance

A lower dose of intravenous alteplase appears to be a safer treatment option than the standard dose, reducing the risk of symptomatic intracerebral hemorrhage. There is uncertainty, however, over how this effect translates into an overall clinical benefit for patients with acute ischemic stroke (AIS).

Objective

To assess whether older, Asian, or severely affected patients with AIS who are considered at high risk of thrombolysis may benefit more from low-dose rather than standard-dose alteplase treatment.

Design, Setting, and Participants

This study is a prespecified secondary analysis of the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED), an international, randomized, open-label, blinded, end-point clinical trial of low-dose vs standard-dose intravenous alteplase for patients with AIS. From March 1, 2012, to August 31, 2015, a total of 3310 patients who had a clinical diagnosis of AIS as confirmed by brain imaging and who fulfilled the local criteria for thrombolysis treatment were included in the alteplase-dose arms. Patients were randomly assigned to receive low-dose (0.6 mg/kg; 15% as bolus and 85% as infusion over 1 hour) or standard-dose (0.9 mg/kg; 10% as bolus and 90% as infusion over 1 hour) alteplase. Of the 3310 randomized patients, 13 patients were excluded for missing consent, mistaken randomization, and duplicate randomization numbers. This secondary analysis was conducted between May 1, 2016, and April 28, 2017.

Main Outcomes and Measures

The primary end point was a poor outcome defined by the combination of death and any disability as scored by the modified Rankin Scale (scores range from 2 to 6, with the highest score indicating death) at 90 days.

Results

Of the 3297 patients included in the analysis, 1248 (37.9%) were women, and the mean (SD) age was 67 (13) years. No significant differences in the treatment effects were observed between low- and standard-dose alteplase for poor outcomes (death or disability) by age, ethnicity, or severity (all P > .37 for interaction). Similarly, the treatment effects of low- vs standard-dose alteplase on function outcome (ordinal shift of the modified Rankin Scale) in Asians (odds ratio, 1.05; 95% CI, 0.90-1.22) was consistent with non-Asians (odds ratio, 0.93; 95% CI, 0.76-1.14) (P = .32 for interaction). There were generally consistent reductions in rates of symptomatic intracerebral hemorrhage with low-dose alteplase, although this reduction was not statistically significant by age, ethnicity, or severity.

Conclusions and Relevance

This analysis found that the effects of low-dose alteplase were not clearly superior to the effects of standard-dose alteplase on death or disability in key demographic subgroups of patients with AIS. Further investigation is required to identify patients with AIS who may benefit from low-dose alteplase.

Trial Registration

clinicaltrials.gov Identifier: NCT01422616.

Efficacy and safety of low dose alteplase for intravenous thrombolysis in Asian stroke patients: a meta-analysis

Whether low dose alteplase is comparable to standard dose in efficacy and safety for intravenous thrombolysis (IVT) in Asian stroke patients remains unverified. PubMed, EMBASE, and Cochrane Library Database from the beginning to June 30, 2017 were searched. IVT efficacy was measured by favorable outcome (modified Rankin Scale scores of 0–1) at 3 months, and safety measured by mortality within 3 months and symptomatic intracerebral hemorrhage (SICH). Pooled estimates were conducted using fixed- or random-effects model depending on heterogeneity. For SICH, studies were pooled separately according to different definitions. Twelve studies involving 7,905 participants were included. No association was found between alteplase dose and favorable outcome (OR = 0.94, 95% CI 0.78–1.14, P = 0.5; heterogeneity: P_hetero = 0.01, I² = 57.3%) and mortality (OR = 0.87, 95% CI 0.74–1.02, P = 0.08; P_hetero = 0.83, I² = 0) using random- and fixed-effects models, respectively. Low dose alteplase was associated with lower SICH as defined by the National Institute of Neurological Disorders and Stroke study (OR = 0.79, 95% CI 0.64–0.99, P = 0.04; P_hetero = 0.57, I² = 0) using fixed-effects model. Subgroup and sensitivity analysis could change the results significantly. Current limited evidence was insufficient to support the speculation that low dose alteplase was comparable to standard dose in thrombolytic efficacy and safety in Asian stroke patients.

Validation of the mSOAR and SOAR scores to predict early mortality in Chinese acute stroke patients

BACKGROUND

It is unclear in Chinese patients with acute stroke how the SOAR (stroke subtype, Oxfordshire Community Stroke Project classification, age, and prestrike modified Rankin) and mSOAR (modified-SOAR) scores performed in predicting discharge mortality and 3-month mortality. We aimed to validate the predictability of these scores in this cohort.

METHODS

Data from the China National Stroke Registry (CNSR) study was used to perform the mSOAR and SOAR scores for predicting the discharge and 3-month mortality in acute stroke patients.

RESULTS

A total of 11073 acute stroke patients were included in present study. The increased mSOAR and SOAR scores were closely related to higher death risk in acute stroke patients. For discharge mortality, the area under the receiver-operator curve (AUC) of the mSOAR and SOAR scores were 0.784 (95% CI 0.761-0.807) and 0.722 (95% CI: 0.698-0.746). For 3-month mortality, they were 0.787 (95% CI: 0.771-0.803) and 0.704 (95% CI: 0.687-0.721), respectively. The mSOAR and SOAR scores showed significant correlation between the predicted and observed probabilities of discharge mortality (mSOAR: r = 0.945, P = 0.001; SOAR: r = 0.994, P<0.001) and 3-month mortality (mSOAR: r = 0.984, P<0.001; SOAR: r = 0.999; P<0.001).

CONCLUSIONS

The mSOAR score predicted reliably the risk of death in Chinese acute stroke patients.

Paradigm Shift for Thrombolysis for Patients with Acute Ischaemic Stroke, from Extension of the Time Window to the Rapid Recanalisation After Symptom Onset

Intravenous thrombolysis (IVT) and intra-arterial thrombolysis (IAT) are useful therapeutic tools to improve functional outcomes after recanalisation of occluded vessels in patients with acute ischaemic stroke. IVT could be performed for more patients by extending the time interval to 4.5 hours from onset to IVT initiation; however, this does not significantly improve functional outcomes. Recent studies indicated that IAT, particularly intra-arterial thrombectomy (IA-thrombectomy), significantly improved functional outcomes after recanalisation of occluded vessels, particularly when the recanalisation was performed within 6 hours of symptom onset. The focus of thrombolysis for acute ischaemic stroke patients is changing from extending the time window for IVT to successfully achieving good functional outcomes with IA-thrombectomy, by performing it within the 6-hour time limit. In this review, we discuss the present status of and limitations of extending IA-thrombectomy for improved functional outcomes after thrombolysis.

Outcome of stroke patients receiving different doses of recombinant tissue plasminogen activator

Background and purpose

Intravenous recombinant tissue plasminogen activator (tPA) at a dose of 0.9 mg/kg body weight is associated with a high hemorrhagic transformation (HT) rate. Low-dose tPA (0.6 mg/kg) may have a lower hemorrhage rate but the mortality and disability rates at 90 days cannot be confirmed as non-inferior to standard-dose tPA. Whether the doses 0.7 and 0.8 mg/kg have better efficacy and safety needs further investigation. Therefore, this study is to compare the efficacy and safety of each dose of tPA (0.6, 0.7, 0.8, and 0.9 mg/kg body weight) and to investigate the factors affecting early neurological improvement (ENI) and early neurological deterioration (END).

Methods

For this observational study, data were obtained from 274 patients who received tPA thrombolytic therapy in Chia-Yi Christian Hospital stroke unit. The tPA dose was given at the discretion of each physician. The definition of ENI was a >8 point improvement (compared with baseline) at 24 h following thrombolytic therapy or an improvement in the National Institutes of Health Stroke Score (NIHSS) to 0 or 1 toward the end of tPA infusion. The definition of END was a >4 point increase in NIHSS (compared with baseline) within 24 h of tPA infusion. The primary objective was to investigate whether 0.7 and 0.8 mg/kg of tPA have higher ENI rate, lower END rate, and better outcome at 6 months. Poor outcome was defined as having a modified Rankin Scale of 3 to 6 (range, 0 [no symptoms] to 6 [death]). The secondary objective was to investigate whether low-dose tPA has a lower risk of intracerebral HT than that with standard-dose tPA. We also investigated the factors affecting ENI, END, HT, and 6-month outcome.

Results

A total of 274 patients were included during the study period, of whom 260 were followed up for >6 months. There was a trend for the HT rate to increase as the dose increased (P=0.02). The symptomatic HT rate was not significantly different among the low-dose and standard-dose groups. The ENI and END (P=0.52) were not significantly different among the four dosage groups. The clinical functional outcome at 6 months after stroke onset was poorer in the standard-dose group (P=0.02). Stroke severity (P<0.01), stroke type (P=0.03), and diabetes mellitus (P=0.04) affected the functional outcome at 6 months.

Conclusion

Among the 274 patients receiving tPA thrombolytic therapy, the HT rate increased as dose increased. The symptomatic HT, ENI and END rates were not significantly different among the low-dose (0.6, 0.7, and 0.8 mg/kg) and standard-dose groups. Stroke severity (NIHSS >12), stroke type (cardioembolism and large artery atherosclerosis) and diabetes mellitus were associated with poor outcome at 6 months.

Special Endovascular Treatment for Acute Large Artery Occlusion Resulting From Atherosclerotic Disease

BACKGROUND

Acute intracranial atherosclerotic disease (IAD)-related large artery occlusion (LAO) is typically refractory to mechanical thrombectomy. We evaluated the feasibility and safety of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration for acute IAD-related LAO.

METHODS

We identified, from among 55 consecutive patients who underwent endovascular treatment for LAO, 12 patients with acute IAD-related LAO who underwent balloon-assisted or stent-assisted angioplasty with (n = 3) or without passage of a stent retriever. The treatment included tirofiban administration. We obtained, from patients' clinical records, thrombolysis in cerebral infarction scores (to assess the extent of reperfusion), follow-up magnetic resonance angiography images (to assess patency of the responsive arteries), and 90-day modified Rankin (mRS) scores (to assess outcomes).

RESULTS

Temporary blood flow and severe stenosis were observed angiographically in all 12 patients, either when the stent retriever was deployed or when a microcatheter was advanced through the site of occlusion. Persistent recanalization was achieved in all patients, and there was no operative complication or arterial reocclusion. All 8 patients with an occluded major artery in the anterior circulation had a good outcome, with an mRS score of ≤2. Two of the 4 patients with basilar artery occlusion had a good outcome, with an mRS score of ≤2. One patient (25%) died within 72 hours after procedure.

CONCLUSIONS

Our data point to the safety and feasibility of emergency balloon-assisted or stent-assisted angioplasty performed with tirofiban administration and a single or no passage of the stent retriever for acute IAD-related LAO.

Low-dose intravenous tissue plasminogen activator for acute ischaemic stroke: an alternative or a new standard?

BACKGROUND

With the recent publication of a large clinical trial on the use of a lower dose of intravenous (IV) tissue plasminogen activator (tPA) for acute ischaemic stroke (AIS), the concept of using a different dose has been debated. We intend to review the literature on using a lower dose of IV tPA and gain a better understanding of the impact of different IV doses on the treatment of patients with AIS.

METHODS

A comprehensive literature search of the related topics in PubMed, EMBASE, Web of Science and MEDLINE was carried out. Key words used include low dose IV tPA, thrombolysis, Alteplace and tPA for AIS. Findings were tabulated according to the size of the cohort studied, outcome, adverse event and level of evidence. The results of all studies using lower doses were analysed for efficacy and adverse events.

RESULTS

From 1992 to 2016, there were 23 trials that included 10 950 patients published on the use of lower doses of IV tPA for AIS. Doses ranged from 0.5, 0.6, 0.75 to 0.85 mg/kg. Most were observational, retrospective and registry studies. One was a prospective open-label randomised controlled trial. 13 trials combined lower doses of IV tPA with a glycoprotein IIb/IIIa inhibitor or thrombectomy. Patients treated with lower doses of IV tPA showed a trend of lower rate of symptomatic intracranial haemorrhage and mortality at 3 months but slightly more disability.

CONCLUSIONS

Lower doses of IV tPA showed less haemorrhagic events but were not more effective compared with the standard dose. The optimal low dose of IV tPA remains unclear. Patients with AIS with a high risk of developing sypmtomatic intracranial haemorrhage might benefit from lower dose IV tPA, such as 0.6 mg/kg.

Report of a workshop on research gaps in the treatment of cerebral palsy

Cerebral palsy (CP) is heterogeneous in etiology and manifestations, making research into relevant therapies difficult and limiting the generalizability of the results. We report here on the NIH CP symposium, where stakeholders from academic, clinical, regulatory, and advocacy backgrounds discussed the major challenges and needs for moving forward with clinical research in CP, and outlined priorities and action items. New information is constantly generated through research into pathogenesis and etiology. Clinical research and new therapeutic approaches need to keep pace, through large data registry integration and new research designs. Development of standardized data collection, increasing academic focus on CP research, and iterative approaches to treatment throughout the patients' lives, have all been identified as areas of focus. The workshop identified critical gaps and areas of focus to increase the evidence base for therapeutic approaches to determine which treatments work best for which patients in the near future. These include consolidation and optimization of databases and registries, updates to the research methodology, and better integration of resources and stakeholders.

Low-Dose versus Standard-Dose Intravenous Alteplase in Acute Ischemic Stroke

BACKGROUND

Thrombolytic therapy for acute ischemic stroke with a lower-than-standard dose of intravenous alteplase may improve recovery along with a reduced risk of intracerebral hemorrhage.

METHODS

Using a 2-by-2 quasi-factorial open-label design, we randomly assigned 3310 patients who were eligible for thrombolytic therapy (median age, 67 years; 63% Asian) to low-dose intravenous alteplase (0.6 mg per kilogram of body weight) or the standard dose (0.9 mg per kilogram); patients underwent randomization within 4.5 hours after the onset of stroke. The primary objective was to determine whether the low dose would be noninferior to the standard dose with respect to the primary outcome of death or disability at 90 days, which was defined by scores of 2 to 6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]). Secondary objectives were to determine whether the low dose would be superior to the standard dose with respect to centrally adjudicated symptomatic intracerebral hemorrhage and whether the low dose would be noninferior in an ordinal analysis of modified Rankin scale scores (testing for an improvement in the distribution of scores). The trial included 935 patients who were also randomly assigned to intensive or guideline-recommended blood-pressure control.

RESULTS

The primary outcome occurred in 855 of 1607 participants (53.2%) in the low-dose group and in 817 of 1599 participants (51.1%) in the standard-dose group (odds ratio, 1.09; 95% confidence interval [CI], 0.95 to 1.25; the upper boundary exceeded the noninferiority margin of 1.14; P=0.51 for noninferiority). Low-dose alteplase was noninferior in the ordinal analysis of modified Rankin scale scores (unadjusted common odds ratio, 1.00; 95% CI, 0.89 to 1.13; P=0.04 for noninferiority). Major symptomatic intracerebral hemorrhage occurred in 1.0% of the participants in the low-dose group and in 2.1% of the participants in the standard-dose group (P=0.01); fatal events occurred within 7 days in 0.5% and 1.5%, respectively (P=0.01). Mortality at 90 days did not differ significantly between the two groups (8.5% and 10.3%, respectively; P=0.07).

CONCLUSIONS

This trial involving predominantly Asian patients with acute ischemic stroke did not show the noninferiority of low-dose alteplase to standard-dose alteplase with respect to death and disability at 90 days. There were significantly fewer symptomatic intracerebral hemorrhages with low-dose alteplase. (Funded by the National Health and Medical Research Council of Australia and others; ENCHANTED ClinicalTrials.gov number, NCT01422616.).

Intravenous Thrombolysis Increases the Rate of Dramatic Recovery in Patients with Acute Stroke with an Unknown Onset Time and Negative FLAIR MRI

BACKGROUND AND PURPOSE

The safety and feasibility of intravenous thrombolysis using recombinant tissue plasminogen activator (IV-tPA) were retrospectively compared between patients with unknown onset time and no ischemia on fluid-attenuated inversion recovery (negative FLAIR) and patients receiving standard therapy.

METHODS

Acute stroke patients with unknown onset times were treated using IV-tPA if they had: negative FLAIR; internal carotid artery and/or middle cerebral artery occlusion; and a diffusion-weighted imaging (DWI)-Alberta Stroke Programme Early CT Score ≥5. All patients had abnormal DWI scans indicating an acute stroke. IV-tPA therapy was performed within 3-4.5 h of first found abnormal time (FAT). Patients who were admitted within 3-4.5 h of FAT and did not receive IV-tPA therapy despite the same imaging findings were extracted from our registry as controls.

RESULTS

There were 24 patients in the IV-tPA group and 28 in the control group. None of the IV-tPA group and 1 (4%) of the control group patients experienced symptomatic intracerebral hemorrhage (P = 1.000). The rate of dramatic recovery at day 7 (≥10-point reduction in the total National Institutes of Health Stroke Scale [NIHSS] score or NIHSS score of 0-1) was 46% in the IV-tPA group and 18% in the control group (P = .038). Multivariate regression analysis revealed that IV-tPA was an independent predictor of dramatic recovery at day 7 (odds ratio 13.74; 95% confidence interval, 1.95-96.92; P = .009).

CONCLUSIONS

IV-tPA may safely increase the rate of dramatic recovery in acute stroke patients with unknown onset times and negative FLAIR.

Low-Dose Versus Standard-Dose Tissue Plasminogen Activator in Acute Ischemic Stroke in Asian Populations: A Meta-Analysis

Recent studies have investigated the most efficacious dose of intravenous tissue plasminogen activator (IV-tPA) for acute ischemic stroke (AIS) patients. There remains no definitive consensus concerning the superior efficacious IV-tPA dose (standard- vs. low-dose), prompting us to perform a meta-analysis comparing the efficacy and safety profile of standard- versus low-dose IV-tPA.We identified relevant studies pertaining to the specific aim of our meta-analysis by searching PubMed and EMBASE (January 1990-September 2015) Either a fixed- or random-effects model was employed (dependent upon data heterogeneity) to analyze the efficacy and safety outcome.Ten cohort studies involving 4389 sum patients were included in the meta-analysis. By using the random-effects model, the meta-analysis indicated no statistically significant difference in favorable functional outcome (modified Rankin scale 0-1) at 3 months (heterogeneity: χ = 17.45, P = 0.04, I = 48%; OR: 0.88 [95% CI: 0.71-1.11]; P = 0.28) and incidence of symptomatic intracranial hemorrhage (SICH) (heterogeneity: χ = 14.41, P = 0.11, I = 38%; OR: 1.19 [95% CI: 0.76 to 1.87]; P = 0.45) between the standard- and low-dose groups. The fixed-effects model demonstrated no significant difference in mortality within 3 months (heterogeneity: χ = 6.73, P = 0.57, I = 0%; OR: 0.91 [95% CI: 0.73-1.12]; P = 0.37) between the standard- and low-dose groups.Low-dose IV-tPA is comparable to standard-dose IV-tPA in both efficacy (favorable functional outcome) and safety (SICH and mortality). Confirmation of these findings through randomized trials is warranted.