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

Specific inhibition on PAI-1 reduces the dose of Alteplase for ischemic stroke treatment

Administration of recombinant tPA (rtPA, or trade name Alteplase®) is an FDA-approved therapy for acute ischemic stroke (AIS), but poses the risk of hemorrhagic complications. Recombinant tPA can be rapidly inactivated by the endogenous inhibitor, plasminogen activator inhibitor 1 (PAI-1). In this work, we study a novel treatment approach that combines a PAI-1 inhibitor, PAItrap4, with a reduced dose of rtPA to address the hemorrhagic concern of rtPA. PAItrap4 is a highly specific and very potent protein-based inhibitor of PAI-1, comprising of a variant of uPA serine protease domain, human serum albumin, and a cyclic RGD peptide. PAItrap4 efficiently targets and inhibits PAI-1 on activated platelets, and also possesses a long half-life in vivo. Our results demonstrate that PAItrap4 effectively counteracts the inhibitory effects of PAI-1 on rtPA, preserving rtPA activity based on amidolytic and clot lysis assays. In an in vivo murine stroke model, PAItrap4, together with low-dose rtPA, enhances the blood perfusion in the stroke-affected areas, reduces infarct size, and promotes neurological recovery in mice. Importantly, such treatment does not increase the amount of cerebral hemorrhage, thus reducing the risk of cerebral hemorrhage. In addition, PAItrap4 does not compromise the normal blood coagulation function in mice, demonstrating its safety as a therapeutic agent. These findings highlight this combination therapy as a promising alternative for the treatment of ischemic stroke, offering improved safety and efficacy.

Analyses on safety and efficacy of non-standard dose of r-tPA in intravenous thrombolysis-treated AIS patients

Background

Intravenous 0.9 mg/kg recombinant tissue plasminogen activator (r-tPA) is one of the most effective treatments in acute ischemic stroke patients. Practically, the dose of r-tPA is still a topic that is constantly being discussed.

Methods

For this observational study, data were obtained from 537 patients who received r-tPA thrombolysis at Shanghai Sixth People's Hospital stroke center over 5 years (2014–2019). Patients were divided into two groups: a non-standard dose group (0.6 mg/kg ≤ dose < 0.9 mg/kg) and a standard dose group (0.9 mg/kg). Different outcomes were observed: efficacy: 3 months mRS 0-1 (3m-mRS0-1); safety: symptomatic intracranial hemorrhage within 24 h (24h-sICH) and 3 months mortality (3m-death). We also observed the effect of r-tPA dose coefficient on outcomes in different age groups and baseline National Institute of Health stroke scale (NIHSS) score subgroups.

Results

There were 265 patients who gave the standard dose treatment and 272 gave the nonstandard dose. There was no significant difference between the non-standard dose group and the standard dose group in 3m-mRS0-1, 3m-death, and 24h-sICH (p = 0.567, 0.327, and 0.415, respectively). The dose coefficient presents a significant negative correlation (p = 0.034, B = −4.290) with 3m-death in NIHSS < 16 sub-group. Door-to-needle time (DNT) is the most important independent outcome-influential factor (MIOIF) in the NIHSS ≥16 sub-group. The diabetes history and baseline NIHSS score were the MIOIF in the age ≥80-year sub-group.

Conclusions

The non-standard dose group (0.6 mg/kg ≤ dose < 0.9 mg/kg) shows no difference in safety and effectiveness than the standard dose group (0.9 mg/kg) in our study. The standard dose should be considered first according to current evidence and Guidelines, but the non-standard dose (0.6 mg/kg ≤ dose < 0.9 mg/kg) might be an option in the actual diagnosis and treatment process considering the patient's clinical profile and financial condition.

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.

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.

Comparison of Different Dosages of Alteplase in Atrial Fibrillation-Related Acute Ischemic Stroke After Intravenous Thrombolysis: A Nationwide, Multicenter, Prospective Cohort Study in Taiwan

Background

Insufficient evidence is available for patients with acute ischemic stroke with atrial fibrillation (AF) to determine the efficacy and safety of different dosages of intravenous thrombolysis treatment. This study examined clinical outcomes in Chinese patients with stroke with and without AF after intravenous thrombolysis treatment with different intravenous thrombolysis doses.

Methods and Results

This multicenter, prospective cohort study recruited 2351 patients with acute ischemic stroke (1371 with AF and 980 without AF) treated with intravenous thrombolysis using alteplase. The Totaled Health Risks in Vascular Events score is a validated risk‐scoring tool used for assessing patients with acute ischemic stroke with and without AF. We evaluated favorable functional outcome at day 90 and symptomatic intracranial hemorrhage within 24 to 36 hours and outcomes of the patients receiving different doses of alteplase. Compared with the non‐AF group, the AF group exhibited a 2‐ to 3‐fold increased risk of symptomatic intracranial hemorrhage according to the National Institute of Neurological Disorders and Stroke standard (relative risk [RR], 2.10 [95% CI, 1.35–3.26]). Favorable functional outcome at 90 days and symptomatic intracranial hemorrhage rates according to the European Cooperative Acute Stroke Study II and the Safe Implementation of Thrombolysis in Stroke‐Monitoring Study standards did not significantly differ between the AF and non‐AF groups. In addition, the low‐dose alteplase subgroup exhibited an increased risk of symptomatic intracranial hemorrhage according to the National Institute of Neurological Disorders and Stroke standard (RR, 2.84 [95% CI, 1.63–4.96]). A validation study confirmed these findings after adjustment for scores determined using different stroke risk‐scoring tools.

Conclusions

Different alteplase dosages did not affect functional status at 90 days in the AF and non‐AF groups. Thus, the adoption of low‐dose alteplase simply because of AF is not recommended.

Predictors of the functional outcome after thrombolysis in an Egyptian patients’ sample

Background

About 6.2 million individuals worldwide and approximately 200 Egyptians/100,000 citizens have cerebrovascular stroke annually, and only less than 1% of stroke patients received intravenous (IV) thrombolysis in 2014. Outcome of the ischemic stroke after IV thrombolysis varies, and there is lack of data about the predicting factors that contributes to the outcome of ischemic strokes after IV thrombolysis in Egypt.

Objective

The aim of this work is to study the predictors of the functional outcome of ischemic cerebrovascular stroke after IV thrombolysis in Egyptian patients.

Patients and methods

This is a prospective study that includes acute ischemic stroke patients who received IV thrombolysis at the Alexandria University Hospital during the year from February 2017 to February 2018, and they were evaluated initially by Rapid Arterial Occlusion Evaluation (RACE) scale and followed-up serially for 6 months after thrombolysis using the National Institutes of Health Stroke Scale (NIHSS) and modified ranking score (mRS).

Results

Forty-five patients are included; 56% had favorable functional outcome (mRS 0–2) after 6 months, 68% had ≥ 4 points improvement in NIHSS after 6 months, and 13% had hemorrhagic conversion with 18% mortality rate. High initial RACE scale and long hospital stay are associated with poor functional outcome 6 months after thrombolysis.

Conclusion

Stroke severity demonstrated by high initial RACE and the duration of hospital stay are the two most significant predictors with an impact on the functional outcome of ischemic cerebrovascular stroke after thrombolysis.

Effect of erroneous body-weight estimation on outcome of thrombolyzed stroke patients

Intravenously administered tissue plasminogen activator (IV-tPA), dose determined by patients' body-weight, remains the only approved drug treatment for acute ischemic stroke (AIS). Since a shorter onset-to-treatment time results in better functional outcome, treatment is often initiated according to the estimated or last-known body-weight of the patient. This approach may result in underdosing or overdosing of tPA. In this multicenter retrospective study, we evaluated the extent of error in tPA dosing in our AIS cohort and its impact on functional outcome and symptomatic intracranial hemorrhage (SICH). Consecutive AIS patients, receiving IV-tPA, dose determined by the estimated body-weight, at three tertiary centers between January and December 2017 were included. Collected data included information about demographics, cardiovascular risk factors, stroke subtype and National Institute of Health Stroke Scale (NIHSS) score. Estimated and measured body-weights were recorded. Modified Rankin scale (mRS) of 2 or more defined unfavorable outcome. The study included 150 patients. Median age was 64 -years (IQR 55-75) with male preponderance (67%) and median NIHSS score of 9 points (IQR 6-17). Mean measured weight of our study population was 58 (SD 13) kg. Median difference between actual and estimated body-weight was 3 kg (IQR 1.5-6). Difference was more than 10% in 35 (23.3%) patients. Good functional outcome (mRS 0-1) was achieved by 74 (49.3%) patients and 10 (6.8%) developed SICH. NIHSS (OR 1.288; 95% CI 1.157-1.435, p < 0.001) and large artery atherosclerosis (OR 5.878; 95% CI 1.929-17.910, p = 0.002) were independent predictors of unfavorable functional outcome. Our finding of the statistically insignificant 2.5-fold increase in poor outcomes among patients where the estimated and actual weight differed by more than 10% should be interpreted with caution due to the limited sample size. Significant difference occurs between estimated and actual body-weight in a considerable proportion of thrombolysed AIS patients. However, this discrepancy does not affect functional outcome or the risk of SICH.

Endovascular thrombectomy without versus with intravenous thrombolysis in acute ischemic stroke: a non-inferiority meta-analysis of randomized clinical trials

OBJECTIVE

To conduct a meta-analysis of randomized trials to comprehensively compare the effect of endovascular thrombectomy (EVT) versus intravenous thrombolysis (IVT) plus EVT on functional independence (modified Rankin Scale (mRS) 0-2) after acute ischemic stroke due to large vessel occlusions (AIS-LVO).

METHODS

We searched Pubmed, EMBASE, CENTRAL, and clinicaltrials.gov from January 2000 to February 2021 and abstracts presented at the International Stroke Conference in March 2021 to identify trials comparing EVT alone versus IVT plus EVT in AIS-LVO. Five non-inferiority margins established in the literature were assessed: -15%, -10%, -6.5%, -5%, and -1.3% for the risk difference for functional independence at 90 days.

RESULTS

Four trials met the selection criteria, enrolling 1633 individuals, with 817 participants randomly assigned to EVT alone and 816 to IVT plus EVT. Crude cumulative rates of 90-day functional independence were 46.0% with EVT alone versus 45.5% with IVT plus EVT. Pooled results showed the risk difference of functional independence was 1% (95% CI -4% to 5%) between EVT alone versus IVT plus EVT. The lower 95% CI bound of -4% fell within the non-inferiority margins of -15%, -10%, -6.5%, and -5%, but not -1.3%. Pooled results also showed the risk difference between EVT alone versus IVT plus EVT was 1% (95% CI -3% to 5%) for mRS 0-1, and 1% (95% CI -1% to 3%) for symptomatic intracranial hemorrhage.

CONCLUSIONS

This meta-analysis suggests that EVT alone is non-inferior to IVT plus EVT for several, but not the most stringent, non-inferiority margins.

The safety and effectiveness of early anti-platelet therapy after alteplase for acute ischemic stroke: A meta-analysis

BACKGROUND

For acute ischemic stroke patients, there is a risk of reocclusion after intravenous thrombolysis. In theory, early anti-platelet therapy can reduce the risk of vessel reocclusion. Although current guidelines do not recommend routine anti-platelet therapy within 24 h of intravenous thrombolytic therapy, many studies disagreed with it, especially after the emergence of new anti-platelet drugs. It is necessary to conduct a meta-analysis based on high-quality randomized controlled studies to re-evaluate this treatment strategy.

METHODS

Literature retrieval was systematically conducted in PubMed, Embase, Cochrane, Web of sicence, clinical trials, CNKI and Wanfang Data, for searching randomized controlled trials (published between January 1, 2000 and April 30, 2020 with no language restrictions) comparing early (within 24 h) with routine (after 24 h) anti-platelet-aggregation therapy after rt-PA intravenous thrombolysis. The primary safety endpoint and primary efficacy indicator are the incidence of symptomatic intracranial hemorrhage and a good prognosis at 90-day (modified Rankin Scale (mRS) score of 0-1 or return to baseline mRS), respectively. We assessed pooled data by use of a random-effects model.

FINDINGS

Of the 378 identified studies, only 3 were eligible and included in our analysis (N = 1008 participants). Compared with routine treatment, early anti-platelet-aggregation therapy after rt-PA intravenous thrombolysis in acute ischemic stroke patients did not affect the 90-day efficacy (95% CI 0.97 - 1.32). In terms of safety assessment, the early use of anti-platelet-aggregation drugs after thrombolysis has a neutral effect on the risk of intracranial hemorrhage, symptomatic intracranial hemorrhage, and bleeding from other systemic sites.

CONCLUSION

Early anti-platelet therapy after alteplase did not benefit the acute ischemic stroke patients based on the current evidence. However, more clinical trials and statistical evidence are still needed.

The role of cell-free DNA in fibrinolysis for intraventricular hemorrhage

OBJECTIVE

Tissue plasminogen activator (tPA) fibrinolysis did not improve functional outcomes of patients with intraventricular hemorrhage (IVH), largely because of the unsatisfactory clot clearance. The presence of neutrophil extracellular traps (NETs) within the clot has been confirmed to impair tPA fibrinolysis, but the mechanism has been unclear. The authors hypothesized that cell-free DNA (cfDNA), the main framework of NETs, might be the important reason for the fibrinolysis resistance, and they validated the hypothesis, hoping to provide a new target to promote intraventricular fibrinolysis.

METHODS

First, cfDNA was detected in IVH clots by immunofluorescence staining in a rat model of IVH. Second, after blood (with or without exogenous cfDNA) intraventricular injection, IVH rats were given intraventricular infusion of 2 μl of saline, tPA, or tPA + DNase1 randomly. Then, the ventricular volume, animal behavior, and reactive astrocyte proliferation were assessed. Third, the IVH clots were collected for fibrinolysis assay in vitro. Finally, the effects of exogenous cfDNA in IVH were evaluated.

RESULTS

The presence of cfDNA in clots was observed as early as 1 hour after IVH. Compared with the whole-blood model, blood + cfDNA caused more severe ventricular dilation (day 7: blood 32.47 ± 2.096 mm3 vs blood + DNA 40.09 ± 2.787 mm3, p < 0.05), increased fibrinolysis resistance to tPA (day 7: tPA + DNA 26.04 ± 1.318 mm3 vs tPA 22.15 ± 1.706 mm3, p < 0.05), and further deteriorated the functional defects in rats (blood vs blood + DNA, p < 0.05). Degradation of cfDNA by DNase1 further enhanced the fibrinolysis effects on relieving the ventricular dilation (day 7: tPA + DNase1 11.67 ± 2.023 mm3 vs tPA, p < 0.05), improving the functional outcome (tPA vs tPA + DNase1, p < 0.05) and reducing periventricular astrocyte proliferation.

CONCLUSIONS

cfDNA impaired tPA fibrinolysis for IVH, and degradation of cfDNA may be a new target to improve this condition.

Assessment of recombinant tissue plasminogen activator (rtPA) toxicity in cultured neural cells and subsequent treatment with poly-arginine peptide R18D

Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) in ischaemic stroke has been associated with neurotoxicity, blood brain barrier (BBB) disruption and intra-cerebral hemorrhage. To examine rtPA cellular toxicity we investigated the effects of rtPA on cell viability in neuronal, astrocyte and brain endothelial cell (bEnd.3) cultures with and without prior exposure to oxygen-glucose deprivation (OGD). In addition, the neuroprotective peptide poly-arginine-18 (R18D; 18-mer of D-arginine) was examined for its ability to reduce rtPA toxicity. Studies demonstrated that a 4- or 24-h exposure of rtPA was toxic, affecting neuronal cell viability at ≥ 2 µM, and astrocyte and bEnd.3 cells viability at ≥ 5 μM. In addition, a 4-h exposure to rtPA after a period of OGD (OGD/rtPA) exacerbated toxicity, affecting neuronal, astrocyte and bEnd.3 cell viability at rtPA concentrations as low as 0.1 µM. Treatment of cells with low concentrations of R18D (0.5 and 1 µM) reduced the toxic effects of rtPA and OGD/rtPA, while on some occasions a higher 2 µM R18D concentrations exacerbated neuronal and bEnd.3 cell toxicity in OGD/rtPA exposed cultures. In exploratory studies we also demonstrated that OGD activates matrix metalloproteinase-9 (MMP-9) release into the supernatant of astrocyte and bEnd.3 cell cultures, but not neuronal cultures, and that OGD/rtPA increases MMP-9 activation. Furthermore, R18D decreased MMP-9 activation in OGD/rtPA treated astrocyte and bEnd.3 cell cultures. In summary, the findings show that rtPA can be toxic to neural cells and that OGD exacerbates toxicity, while R18D has the capacity to reduce rtPA neural cellular toxicity and reduce MMP-9 activation in astrocytes and bEnd.3. Poly-arginine-18 peptides, which are being developed as neuroprotective therapeutics for ischaemic stroke, therefore have the additional potential of reducing cytotoxic effects associated with rtPA thrombolysis in the treatment of ischaemic stroke.

High Neutrophil-to-Lymphocyte Ratio Predicts Hemorrhagic Transformation in Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis

Background

The relationship between the neutrophil-to-lymphocyte ratio (NLR) and hemorrhagic transformation (HT) in acute ischemic stroke (AIS) treated with intravenous thrombolysis (IVT) remains unclear. This study assessed whether high NLR is associated with HT in this population.

Methods

Data were prospectively collected for continuous patients with AIS treated with IVT and retrospectively analyzed. Clinical variables included age, sex, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score, onset-to-treatment time, and initial hematologic and neuroimaging findings. HT was confirmed by imaging performed within 3 days after IVT. Symptomatic HT (sHT) was defined as NIHSS score increased by 4 points compared with that on admission according to previously published criteria. The NLR value was based on the blood examination before IVT, and high NLR was defined as ≥75th percentile.

Results

The study included 285 patients (201 (70.5%) males, the mean age was 62.3 years (range 29-89)). Seventy-two (25.3%) patients presented with HT, including three (1.1%) with sHT. The median NLR was 2.700 (1.820-4.255, interquartile range). Seventy-one (24.9%) patients had a high NLR (≥4.255) on admission. Univariate analysis indicated that patients with HT had higher NIHSS scores (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (P < 0.001), systolic blood pressure (SBP), platelet counts, lymphocyte counts, and NLR (.

Conclusions

High NLR could be a useful marker for predicting HT in AIS patients after IVT.

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.

Similar thrombolysis outcomes in acute stroke patients with and without atrial fibrillation if pre-stroke CHA2DS2-VASc score is low: A retrospective study

The prognosis of acute ischemic stroke patients treated with intravenous (IV) recombinant tissue plasminogen activator (rtPA) is poorer in patients with atrial fibrillation (AF) than patients without AF, which might be related to the greater stroke severity in AF patients. Higher pre-stroke CHA2DS2-VASc scores are associated with greater stroke severity and poorer outcomes. AF Patients tend to have higher CHA2DS2-VASc scores than the non-AF patients. We thus hypothesized that pre-stroke CHA2DS2-VASc scores can be used to improve outcome stratification of IV thrombolysis therapy in acute stroke patients with and without AF. We retrospectively enrolled ischemic stroke patients who received IV-rtPA and categorized them into 2 groups: low-risk (CHA2DS2-VASc scores ≤ 2) and high-risk (CHA2DS2-VASc scores ≥ 3) groups. We compared the outcomes between AF and non-AF patients and the interactive effects of the levels of CHA2DS2-VASc scores on this outcome difference. In the low-risk group, there was no difference in outcomes between the AF and non-AF patients. In the high-risk group, the AF patients had worse outcomes at 3 and 6 months. Our results suggest that pre-stroke CHA2DS2-VASc scores are a useful outcome predictor of IV thrombolytic therapy in acute stroke patients with AF.

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.

The rate of early neurological deterioration occurring after thrombolytic therapy: A meta-analysis

OBJECTIVES

The rate of early neurological deterioration (END) occurring after thrombolytic therapy is controversial. To explore a more precise estimation of the rate, a meta-analysis was conducted in the present study.

METHODS

The relevant studies were identified by searching PubMed, EMBASE, and Cochrane Collaboration Database up to June 2018. The definition of END was prespecified according to the most commonly used definition: ≥4-point increase in National Institutes of Health Stroke Scale between admission and 24 hr. The meta-analysis was performed by using the STATA 12.

RESULTS

Eleven studies with a total of 3,539 subjects, including 373 patients with END and 3,166 patients without END, were collected. The pooled analysis showed that the rate of END occurring after thrombolytic therapy was about 11.0% (95% CI: 7.8%-14.3%). Subgroup analysis by continent showed that the rate of END occurring after thrombolytic therapy of patients in Asia (15.9%, 95% CI: 7.4%-24.5%) was higher than in Europe (7.6%, 95% CI: 4.9%-10.3%) and in North America (11.8%, 95% CI: 8.5%-15.0%). Subgroup analysis by onset to treatment time (OTT) displayed that the rate of END occurring after thrombolytic therapy was 5.4% (95% CI: 1.2%-9.5%), 15.6% (95% CI: 9.6%-21.5%), and 18.5% (95% CI: 11.2%-25.8%) for the patients whose OTT ≤120.0 min, from 120.1 to 179.9 min, from 180.0 to 270.0 min, respectively.

CONCLUSION

The rate of END occurring after thrombolytic therapy is about 11.0%. This finding may provide a scientific reference for researchers to evaluate the efficacy and safety of thrombolytic therapy.

Cerebral Hypoperfusion and Other Shared Brain Pathologies in Ischemic Stroke and Alzheimer's Disease

Newly emerged evidence reveals that ischemic stroke and Alzheimer's disease (AD) share pathophysiological changes in brain tissue including hypoperfusion, oxidative stress, immune exhaustion, and inflammation. A mechanistic link between hypoperfusion and amyloid β accumulation can lead to cell damage as well as to motor and cognitive deficits. This review will discuss decreased cerebral perfusion and other related pathophysiological changes common to both ischemic stroke and AD, such as vascular damages, cerebral blood flow alteration, abnormal expression of amyloid β and tau proteins, as well as behavioral and cognitive deficits. Furthermore, this review highlights current treatment options and potential therapeutic targets that warrant further investigation.

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.