Alteplase at 0.6 mg/kg for Acute Ischemic Stroke Within 3 Hours of Onset

Effect of Mechanical Thrombectomy Without vs With Intravenous Thrombolysis on Functional Outcome Among Patients With Acute Ischemic Stroke: The SKIP Randomized Clinical Trial

IMPORTANCE

Whether intravenous thrombolysis is needed in combination with mechanical thrombectomy in patients with acute large vessel occlusion stroke is unclear.

OBJECTIVE

To examine whether mechanical thrombectomy alone is noninferior to combined intravenous thrombolysis plus mechanical thrombectomy for favorable poststroke outcome.

DESIGN, SETTING, AND PARTICIPANTS

Investigator-initiated, multicenter, randomized, open-label, noninferiority clinical trial in 204 patients with acute ischemic stroke due to large vessel occlusion enrolled at 23 hospital networks in Japan from January 1, 2017, to July 31, 2019, with final follow-up on October 31, 2019.

INTERVENTIONS

Patients were randomly assigned to mechanical thrombectomy alone (n = 101) or combined intravenous thrombolysis (alteplase at a 0.6-mg/kg dose) plus mechanical thrombectomy (n = 103).

MAIN OUTCOMES AND MEASURES

The primary efficacy end point was a favorable outcome defined as a modified Rankin Scale score (range, 0 [no symptoms] to 6 [death]) of 0 to 2 at 90 days, with a noninferiority margin odds ratio of 0.74, assessed using a 1-sided significance threshold of .025 (97.5% CI). There were 7 prespecified secondary efficacy end points, including mortality by day 90. There were 4 prespecified safety end points, including any intracerebral hemorrhage and symptomatic intracerebral hemorrhage within 36 hours.

RESULTS

Among 204 patients (median age, 74 years; 62.7% men; median National Institutes of Health Stroke Scale score, 18), all patients completed the trial. Favorable outcome occurred in 60 patients (59.4%) in the mechanical thrombectomy alone group and 59 patients (57.3%) in the combined intravenous thrombolysis plus mechanical thrombectomy group, with no significant between-group difference (difference, 2.1% [1-sided 97.5% CI, -11.4% to ∞]; odds ratio, 1.09 [1-sided 97.5% CI, 0.63 to ∞]; P = .18 for noninferiority). Among the 7 secondary efficacy end points and 4 safety end points, 10 were not significantly different, including mortality at 90 days (8 [7.9%] vs 9 [8.7%]; difference, -0.8% [95% CI, -9.5% to 7.8%]; odds ratio, 0.90 [95% CI, 0.33 to 2.43]; P > .99). Any intracerebral hemorrhage was observed less frequently in the mechanical thrombectomy alone group than in the combined group (34 [33.7%] vs 52 [50.5%]; difference, -16.8% [95% CI, -32.1% to -1.6%]; odds ratio, 0.50 [95% CI, 0.28 to 0.88]; P = .02). Symptomatic intracerebral hemorrhage was not significantly different between groups (6 [5.9%] vs 8 [7.7%]; difference, -1.8% [95% CI, -9.7% to 6.1%]; odds ratio, 0.75 [95% CI, 0.25 to 2.24]; P = .78).

CONCLUSIONS AND RELEVANCE

Among patients with acute large vessel occlusion stroke, mechanical thrombectomy alone, compared with combined intravenous thrombolysis plus mechanical thrombectomy, failed to demonstrate noninferiority regarding favorable functional outcome. However, the wide confidence intervals around the effect estimate also did not allow a conclusion of inferiority.

TRIAL REGISTRATION

umin.ac.jp/ctr Identifier: UMIN000021488.

Magnetic Resonance Imaging-Guided Thrombolysis (0.6 mg/kg) Was Beneficial for Unknown Onset Stroke Above a Certain Core Size: THAWS RCT Substudy

BACKGROUND AND PURPOSE

We determined to identify patients with unknown onset stroke who could have favorable 90-day outcomes after low-dose thrombolysis from the THAWS (Thrombolysis for Acute Wake-Up and Unclear-Onset Strokes With Alteplase at 0.6 mg/kg) database.

METHODS

This was a subanalysis of an investigator-initiated, multicenter, randomized, open-label, blinded-end point trial. Patients with stroke with a time last-known-well >4.5 hours who showed a mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg intravenously or standard medical treatment. The patients were dichotomized by ischemic core size or National Institutes of Health Stroke Scale score, and the effects of assigned treatments were compared in each group. The efficacy outcome was favorable outcome at 90 days, defined as a modified Rankin Scale score of 0 to 1.

RESULTS

The median DWI-Alberta Stroke Program Early CT Score (ASPECTS) was 9, and the median ischemic core volume was 2.5 mL. Both favorable outcome (47.1% versus 48.3%) and any intracranial hemorrhage (26% versus 14%) at 22 to 36 hours were comparable between the 68 thrombolyzed patients and the 58 control patients. There was a significant treatment-by-cohort interaction for favorable outcome between dichotomized patients by ASPECTS on DWI (P=0.026) and core volume (P=0.035). Favorable outcome was more common in the alteplase group than in the control group in patients with DWI-ASPECTS 5 to 8 (RR, 4.75 [95% CI, 1.33-30.2]), although not in patients with DWI-ASPECTS 9 to 10. Favorable outcome tended to be more common in the alteplase group than in the control group in patients with core volume >6.4 mL (RR, 6.15 [95% CI, 0.87-43.64]), although not in patients with volume ≤6.4 mL. The frequency of any intracranial hemorrhage did not differ significantly between the 2 treatment groups in any dichotomized patients.

CONCLUSIONS

Patients developing unknown onset stroke with DWI-ASPECTS 5 to 8 showed favorable outcomes more commonly after low-dose thrombolysis than after standard treatment. Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02002325. URL: https://www.umin.ac.jp/ctr; Unique Identifier: UMIN000011630.

Acute ischemic stroke management: concepts and controversies.A narrative review

INTRODUCTION

Amongst the 25.7 million survivors and 6.5 million deaths from stroke between 1990 and 2013, ischemic strokes accounted for approximately 70% and 50% of the cases, respectively. With patients still suffering from complications and stroke recurrence, more questions have been raised as to how we can better improve patient management.

AREAS COVERED

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and Newcastle-Ottawa Scale (NOS) were adopted to ensure a comprehensive inclusion of quality literature from various sources. PubMed and Embase were searched for evidence on thrombolysis, mechanical thrombectomy, artificial intelligence (AI), antiplatelet therapy, anticoagulation and hypertension management.

EXPERT OPINION

The directions of future research in these areas are dependent on the current level of validation. Endovascular therapy and applications of AI are relatively new compared to the other areas discussed in this review. As such, future studies need to focus on validating their efficacy. As for thrombolysis, antiplatelet and anticoagulation therapy, their efficacy has been well-established and future research efforts should be directed toward adjusting its use according to patient-specific factors, starting with factors with the most clinical relevance and prevalence.

Stroke

Stroke is a major cause of death and disability globally. Diagnosis depends on clinical features and brain imaging to differentiate between ischaemic stroke and intracerebral haemorrhage. Non-contrast CT can exclude haemorrhage, but the addition of CT perfusion imaging and angiography allows a positive diagnosis of ischaemic stroke versus mimics and can identify a large vessel occlusion target for endovascular thrombectomy. Management of ischaemic stroke has greatly advanced, with rapid reperfusion by use of intravenous thrombolysis and endovascular thrombectomy shown to reduce disability. These therapies can now be applied in selected patients who present late to medical care if there is imaging evidence of salvageable brain tissue. Both haemostatic agents and surgical interventions are investigational for intracerebral haemorrhage. Prevention of recurrent stroke requires an understanding of the mechanism of stroke to target interventions, such as carotid endarterectomy, anticoagulation for atrial fibrillation, and patent foramen ovale closure. However, interventions such as lowering blood pressure, smoking cessation, and lifestyle optimisation are common to all stroke subtypes.

High White Blood Cell Count Is a Risk Factor for Contrast-Induced Nephropathy following Mechanical Thrombectomy for Acute Ischemic Stroke

BACKGROUND

Although mechanical thrombectomy is a standard endovascular therapy for patients with acute ischemic stroke (AIS), the incidence of and risk factors for contrast-induced nephropathy (CIN) following mechanical thrombectomy are infrequently reported.

OBJECTIVES

The aim of this study was to investigate the incidence and risk factors for CIN following mechanical thrombectomy for AIS, and whether the incidence of CIN is related to a poor prognosis.

METHODS

We examined consecutive patients who underwent a mechanical thrombectomy in the period from January 2014 to March 2018. The patients' clinical backgrounds, treatments, and clinical prognoses were analyzed. CIN was defined as an increase in the serum creatinine level of ≥44.2 μmol/L (0.5 mg/dL) or 25% above baseline within 72 h after exposure to the contrast medium.

RESULTS

In total, 80 patients (46 men and 34 women aged 74.5 ± 11.5 years) who met our inclusion criteria were analyzed. CIN occurred in 8.8% (7/80) of the patients following mechanical thrombectomy. Although no patients needed permanent dialysis, 1 required temporary dialysis. The median amount of contrast medium was 109 mL. A comparison between the groups with and without CIN showed a significant difference in white blood cell (WBC) count at the time of admission (11.6 ± 2.7 × 103/μL and 8.1 ± 2.7 × 103/μL; p < 0.01) and the cut-off value was 9.70 × 103/μL. In multivariate analysis, contrast volume/estimated glomerular filtration rate by creatinine and WBC count were significantly associated with the incidence of CIN, with odds ratios of 1.64 (95% CI 1.02-2.65; p = 0.04) and 1.61 (95% CI 1.15-2.25; p < 0.01), respectively.

CONCLUSIONS

This study found that CIN occurred in 8.8% of patients with AIS following mechanical thrombectomy. High WBC count was associated with an increased risk of CIN and may be helpful for predicting CIN.

Acute Ischemic Stroke: Acute Management and Selection for Endovascular Therapy

Stroke is a medical emergency and expeditious treatment is critical to reducing permanent disability or death. Acute management of patients suffering from acute ischemic stroke (AIS) requires early recognition of symptoms, rapid assessment and stabilization (hyperacute workup), and appropriate selection of patients for reperfusion with intravenous alteplase and/or mechanical thrombectomy. Established stroke protocols which involve both prehospital emergency medical services and in-hospital multidisciplinary stroke teams have been shown to be crucial to reducing the long term, devastating effects of stroke.

C-reactive Protein is A Predictor of Deterioration of Acute Internal Carotid Artery M1 Qcclusion Following Recanalization

INTRODUCTION

Administration of intravenous recombinant tissue plasminogen activator (rt-PA) and mechanical thrombectomy (MT) have become standard therapeutic approaches for acute internal carotid artery and middle cerebral artery M1 segment occlusion (ICA/M1O). However, clinical deterioration of the condition is still observed in some cases.

OBJECTIVE

We aimed to identify patients' factors associated with exacerbation. This was a single-center, retrospective study of 35 consecutive patients with acute ICA/M1O who underwent rt-PA/rt-PA and MT at our hospital between January 2016 and September 2019. We divided patients into two groups based on the total NIHSS score at discharge: the "improvement" and "exacerbation" groups. Clinical characteristics, laboratory data, and imaging findings were compared between the groups.

RESULTS

The improvement group (13 patients [37%]) had a lower mean age (70 vs. 81 years, p = 0.02), National Institutes of Health Stroke Scale score (NIHSS, 13 vs. 19, p = 0.02), and C-reactive protein (CRP) levels (0.24 vs. 0.92 mg/dl, p < 0.01) than the exacerbation group (22 patients [63%]). Receiver operating characteristic curve analysis revealed the cut-off age to be 79 (sensitivity 76.9%, specificity 72.7%), NIHSS score to be 20 (sensitivity 92.3%, specificity 63.6%), and CRP to be 0.14 mg/dl (sensitivity 69.2%, specificity 81.8%). Multivariate analysis confirmed a CRP level of >0.14 mg/dl (odds ratio, 10.16; 95% confidence interval 1.38-75.13; p = 0.01) to be independently associated with clinical deterioration at discharge.

CONCLUSIONS

A CRP level of >0.14 mg/dl is a strong predictor of clinical deterioration at discharge in patients with acute ICA/M1O undergoing recanalization therapy.

Outcome and effect of endovascular treatment in stroke associated with acute extracranial internal carotid artery occlusion: Single-center experience in Japan

BACKGROUND

Positive data from several randomized controlled trials (RCTs) of endovascular treatment (EVT) for acute ischemic stroke (AIS) patients with anterior circulation large vessel occlusion (ACLVO) have emerged. However, little evidence exists on EVT for acute extracranial internal carotid artery (EC-ICA) occlusion. We therefore analysed the outcome and effect of EVT on AIS due to ACLVO caused by EC-ICA occlusion, including tandem occlusion compared with that caused by pure intracranial artery occlusion.

METHODS

A total of 135 consecutive AIS patients with ACLVO between July 2014 and December 2017 were identified. We retrospectively analysed the efficacy of EVT for ACLVO after introducing a stent retriever (SR). We classified ACLVO into the following categories: group A, intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion), and group B, ipsilateral EC-ICA occlusion with/without intracranial artery occlusion.

RESULTS

In total, 65 patients were enrolled. Group A comprised 71% (46/65) of all cases. No difference was observed in terms of age, National Institute of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomography Score-Diffusion Weighted imaging (ASPECTS-DWI), several clinical time intervals, rate of successful revascularization (74% versus 84%), and rate of functional independence (42% versus 39%) between groups A and B. In all patients, an ASPECTS-DWI ≥6 and an onset-to-door time ≤6 h were associated with good outcome, whereas intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion) was not.

CONCLUSIONS

The outcomes support the efficacy of EVT in stroke associated with acute EC-ICA occlusion. In the EVT of AIS due to ACLVO, there was no significant difference in the results between ipsilateral EC-ICA occlusion with/without intracranial artery occlusion and intracranial artery occlusion without EC-ICA occlusion (pure intracranial artery occlusion).

Clinical Outcome of Patients With Large Vessel Occlusion and Low National Institutes of Health Stroke Scale Scores

Background and Purpose—

The treatment and prognosis of acute large vessel occlusion with mild symptoms have not been sufficiently studied. The present study aimed to investigate the clinical or radiological predictors of clinical outcome in patients with stroke with mild symptoms due to acute large vessel occlusion.

Methods—

Of 2420 patients with acute large vessel occlusion in the RESCUE-Japan Registry 2 (Recovery by Endovascular Salvage for Cerebral Ultra-Acute Embolism-Japan Registry 2), a multicenter prospective registry in Japan, patients with modified Rankin Scale scores of 0 to 2 before onset and initial National Institutes of Health Stroke Scale (NIHSS) scores of 0 to 5 were examined in post hoc analysis. We examined the clinical and radiological characteristics associated with a favorable outcome (modified Rankin Scale score, 0–2 at 90 days) using multivariate analysis, as well as the factors associated with a favorable outcome in patients treated with endovascular therapy.

Results—

We analyzed 272 patients (median age, 73 years; median NIHSS score on admission, 3). Eighty-six (31.6%) patients were treated with intravenous recombinant tissue-type plasminogen activator, 54 (19.9%) underwent endovascular therapy, and 208 (76.5%) showed a favorable outcome. In multivariate analysis, age <75 years (odds ratio [OR], 2.42 [95% CI, 1.30–4.50]), initial NIHSS score 0 to 3 (OR, 3.08 [95% CI, 1.59–5.98]), intravenous recombinant tissue-type plasminogen activator (OR, 2. 86 [95% CI, 1.32–6.21]), and blood glucose level ≤140 mg/dL (OR, 2.37 [95% CI, 1.22–4.60]) were independently associated with a favorable outcome. However, endovascular therapy was not associated with a favorable outcome (OR, 1.65 [95% CI, 0.71–3.88]). Among 54 patients treated with endovascular therapy, good reperfusion status was more common in the favorable outcome group (88.6% versus 60.0%; P <0.05).

Conclusions—

Younger age, lower initial NIHSS score, intravenous recombinant tissue-type plasminogen activator, and absence of hyperglycemia were independently associated with a favorable outcome in patients with acute large vessel occlusion with low NIHSS scores.

Registration—

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02419794.

Thrombolysis With Alteplase at 0.6 mg/kg for Stroke With Unknown Time of Onset: A Randomized Controlled Trial

Supplemental Digital Content is available in the text.

We assessed whether lower-dose alteplase at 0.6 mg/kg is efficacious and safe for acute fluid-attenuated inversion recovery-negative stroke with unknown time of onset.

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.

Comparison of Clinical Care and In-Hospital Outcomes of Asian American and White Patients With Acute Ischemic Stroke

Importance

Although overall stroke incidence and mortality in the United States is improving, little is known about the characteristics and clinical outcomes of acute ischemic stroke in Asian American individuals.

Objective

To compare the characteristics, care, and outcomes of Asian American and white patients with acute ischemic stroke.

Design, Setting, Participants

Retrospective analysis of Asian American and white patients admitted with a primary diagnosis of acute ischemic stroke to hospitals participating in the Get With The Guidelines-Stroke (GWTG-Stroke) program between April 1, 2004, and July 31, 2016. The GWTG-Stroke database is a prospectively collected stroke quality improvement registry sponsored by the American Heart Association/American Stroke Association.

Main Outcomes and Measures

Multivariable logistic regression models assessed the association of Asian American race/ethnicity, clinical outcomes, and quality measures.

Results

The study population of 1 772 299 patients (mean [SD] age, 72.4 [14.2] years; 51.3% female) consisted of 64 337 Asian American patients (3.6%) and 1 707 962 white patients (96.4%) admitted to 2171 GWTG-Stroke hospitals with acute ischemic stroke. After adjustment for patient and hospital variables, Asian American patients were seen with greater stroke severity compared with white patients (National Institutes of Health Stroke Scale [NIHSS] score ≥16) (odds ratio [OR], 1.35; 95% CI, 1.30-1.40; P < .001), manifested higher in-hospital mortality (OR, 1.14; 95% CI, 1.09-1.19; P < .001), had longer length of stay (OR, 1.17; 95% CI, 1.14-1.20; P < .001), and were less likely to ambulate independently at discharge (OR, 0.84; 95% CI, 0.79-0.90; P < .001). Although Asian American patients had fewer intravenous tissue plasminogen activator (IV tPA) administrations than white patients (OR, 0.95; 95% CI, 0.91-0.98; P = .003), they had more symptomatic hemorrhage after tPA (OR, 1.36; 95% CI, 1.20-1.55; P < .001) and overall post-tPA complications (OR, 1.31; 95% CI, 1.18-1.46; P < .001). Asian American patients had better quality measure adherence overall than white patients, including rehabilitation (OR, 1.27; 95% CI, 1.18-1.36; P < .001), door to tPA within 60 minutes (OR, 1.14; 95% CI, 1.06-1.22; P < .001), and intensive statin therapy (OR, 1.14; 95% CI, 1.10-1.18; P < .001). After adjustment for stroke severity, Asian American patients had lower in-hospital mortality than white patients (OR, 0.95; 95% CI, 0.91-0.99; P = .008).

Conclusions and Relevance

Asian American patients manifested more severe ischemic strokes, were less likely to receive IV tPA, and had worse functional outcomes than white patients. These findings warrant additional research toward improving clinical outcomes for Asian American patients with acute ischemic stroke.

Clinical features and efficacy of reperfusion therapy in minor ischemic stroke patients with atrial fibrillation

The efficacy of reperfusion therapy (RT) using intravenous infusion of recombinant tissue plasminogen activator and/or endovascular therapy for minor ischemic stroke (MIS) has not yet been established. The present study aimed to elucidate the clinical features of MIS patients with atrial fibrillation (AF) and examine whether they could be potential candidates for RT. Data of MIS patients, defined as those with a score ≤ 5 on the National Institute of Health Stroke Scale, were extracted from patients admitted to our hospital between 2006 and 2018, and clinical characteristics were compared between the AF and non-AF groups. Thereafter, the impact of RT on outcomes in the AF- group was evaluated using the modified Rankin scale (mRS) score 3 months after onset and compared to that of standard medical therapy (SMT) using propensity score matching (PSM). Of 10,483 stroke patients, 3003 were shortlisted, and 457 AF patients and 2546 non-AF patients were finally selected. Patients in the AF group had more RT (13.3% vs. 5.7%, p < 0.001) than those in the non-AF group. Using PSM, 53 patients each were extracted from the AF-RT and AF-SMT groups. The frequencies of mRS = 0 or 1 for the AF-RT and AF-SMT groups were 69.8% and 64.2% (p = 0.536), respectively, with a significant difference in mRS = 0 (56.5% vs. 34.0%, p = 0.019). The present study found that MIS patients with AF underwent more RT than those without AF and that RT compared favorably with SMT for them; further study is warranted to examine whether these patients could be good candidates for RT.

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.

Key Role of Cytochrome C for Apoptosis Detection Using Raman Microimaging in an Animal Model of Brain Ischemia with Insulin Treatment

Brain ischemia represents a leading cause of death and disability in industrialized countries. To date, therapeutic intervention is largely unsatisfactory and novel strategies are required for getting better protection of neurons injured by cerebral blood flow restriction. Recent evidence suggests that brain insulin leads to protection of neuronal population undergoing apoptotic cell death via modulation of oxidative stress and mitochondrial cytochrome c (CytC), an effect to be better clarified. In this work, we investigate on the effect of insulin given intracerebroventricular (ICV) before inducing a transient global ischemia by bilateral occlusion of the common carotid arteries (BCCO) in Mongolian gerbils (MG). The transient (3 min) global ischemia in MG is observed to produce neurodegenerative effect mainly into CA3 hippocampal region, 72 h after cerebral blood restriction. Intracerebroventricular microinfusion of insulin significantly prevents the apoptosis of CA3 hippocampal neurons. Histological observation, after hematoxylin and eosin staining, puts in evidence the neuroprotective role of insulin, but Raman microimaging provides a clearer insight in the CytC mechanism underlying the apoptotic process. Above all, CytC has been revealed to be an outstanding, innate Raman marker for monitoring the cells status, thanks to its resonant scattering at 530 nm of incident wavelength and to its crucial role in the early stages of cells apoptosis. These data support the hypothesis of an insulin-dependent neuroprotection and antiapoptotic mechanism occurring in the brain of MG undergoing transient brain ischemia. The observed effects occurred without any peripheral change on serum glucose levels, suggesting an alternative mechanism of insulin-induced neuroprotection.

Simultaneous cardio-cerebral embolization associated with atrial fibrillation: a case report

Background

Simultaneous cerebral and myocardial infarction is called cardiocerebral infarction (CCI), and is rarely encountered. Because of the narrow time window and complex pathophysiology, CCI is challenging to immediately diagnose and treat.

Case presentation

A 73-year-old woman suddenly developed right hemiplegia and severe aphasia. Twelve-lead electrocardiography showed tachycardic atrial fibrillation without any significant ST-T change. Magnetic resonance imaging revealed a proximal middle cerebral artery occlusion. She was immediately treated with alteplase at the dosage approved for ischemic stroke followed by mechanical thrombectomy as bridging therapy, and complete recanalization was achieved. Aphasia improved and she began to complain of chest pain, and reported that she had experienced chest discomfort just prior to right limb weakness. Coronary angiography showed a partial filling defect in the right coronary artery with rapid and adequate distal flow, for which percutaneous coronary intervention was not required. Alteplase was suggested to have effectively resolved the coronary emboli. The occlusions of the cerebral and coronary arteries were assumed to have occurred nearly simultaneously and cardiogenic embolism due to atrial fibrillation was considered as the most likely etiology.

Conclusions

As seen in the present case, CCI may benefit from immediate treatment with intravenous tissue plasminogen activator (IV-tPA). Although which of percutaneous coronary intervention or cerebral thrombectomy should be performed first remains unclear, we must decide whether to rescue the brain or heart first in each patient within a limited window of time. This dilemma has recently become evident in this era with mechanical thrombectomy strongly established as an effective intervention for acute ischemic stroke. Close cooperation between stroke physicians and cardiologists is becoming more important.

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.

Effectiveness of Low-Dose Intravenous Tissue Plasminogen Activator before Stent Retriever or Aspiration Mechanical Thrombectomy

PURPOSE

To determine whether thrombolysis with a lower dose of intravenous recombinant tissue plasminogen activator before mechanical thrombectomy is beneficial for functional outcomes compared with mechanical thrombectomy alone.

MATERIALS AND METHODS

Data for 100 Japanese patients who underwent mechanical thrombectomy between July 2014 and November 2017 were retrospectively reviewed. These patients were divided into groups according to whether they received intravenous thrombolysis before mechanical thrombectomy, and outcomes were compared. Favorable outcome was defined as a modified Rankin scale score ≤ 2 at 3 months after treatment.

RESULTS

Thirty-four patients for the thrombolysis group and 66 patients for the thrombectomy-only group were identified. The thrombolysis and nonthrombolysis groups did not differ significantly in baseline characteristics (mean age, 74.3 y vs 75.7 y [P = .485]; mean preoperative National Institute Health Stroke Scale score, 19.8 vs 19.6 [P = .825]). There were no significant differences in the times required for, or the rates of, successful recanalization. However, the thrombolysis group had a higher rate of complete recanalization (67.6% vs 43.9%; P = .041). Postoperative symptomatic intracranial hemorrhage was not significantly different between groups. Favorable outcomes were observed in 73.5% of patients in the thrombolysis group and 51.5% in the nonthrombolysis group (P = .028).

CONCLUSIONS

This single-center retrospective study shows that lower-dose intravenous thrombolysis improves the outcomes of mechanical thrombectomy for Japanese patients with acute anterior-circulation stroke treated within 4.5 hours of onset.

The randomized study of endovascular therapy with versus without intravenous tissue plasminogen activator in acute stroke with ICA and M1 occlusion (SKIP study)

Rationale

Bridging therapy with endovascular therapy (EVT) and intravenous thrombolysis (IVT) has been reported to improve outcomes for acute stroke patients with large-vessel occlusion in the anterior circulation. While the IVT may increase the reperfusion rate, the risk of hemorrhagic complications increases. Whether EVT without IVT (direct EVT) is equally effective as bridging therapy in acute stroke remains unclear.

Aim

This randomized study of endovascular therapy with versus without intravenous tissue plasminogen activator for acute stroke with ICA and M1 occlusion aims to clarify the efficacy and safety of direct EVT compared with bridging therapy.

Methods and design

This is an investigator-initiated, multicenter, prospective, randomized, open-treatment, blinded-endpoint clinical trial. The target patient number is 200, comprising 100 patients receiving direct EVT and 100 receiving bridging therapy.

Study outcome

The primary efficacy endpoint is a modified Rankin Scale score of 0–2 at 90 days. Safety outcome measures are any intracranial hemorrhage at 24 h.

Discussion

This trial may help determine whether direct EVT should be recommended as a routine clinical strategy for ischemic stroke patients within 4.5 h from onset. Direct EVT would then become the choice of therapy in stroke centers with endovascular facilities.

Trial registration

UMIN000021488.

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.

Utility of Minimum Apparent Diffusion Coefficient Ratios in Alberta Stroke Program Early CT Score Regions for Deciding on Stroke Therapy

BACKGROUND AND PURPOSE

Therapeutic indications for recombinant tissue plasminogen activator therapy and endovascular therapy need to be assessed for patients with hyperacute ischemic stroke. We investigated the relationship between the minimum apparent diffusion coefficient ratios in each Alberta Stroke Program Early CT Score region and reversible lesion in patients with hyperacute ischemic stroke receiving recombinant tissue plasminogen activator therapy and/or treated with endovascular therapy.

MATERIALS AND METHODS

We retrospectively evaluated 29 patients with first ischemic stroke due to stenosis/occlusion of the internal carotid artery or horizontal portion of the middle cerebral artery that was successfully recanalized by recombinant tissue plasminogen activator therapy and/or treated with endovascular therapy. We measured the minimum apparent diffusion coefficient value in each Alberta Stroke Program Early CT Score region (11 regions) and calculated the ratio.

RESULTS

There was a significant difference in minimum apparent diffusion coefficient ratios between regions that included and did not include infarction (P < .0001), which were distinguishable with a cutoff value of .808 (area under the curve = .80, P < .001). A statistical difference in the proportion of infarction with the cutoff value was observed between patients treated with endovascular therapy and receiving recombinant tissue plasminogen activator therapy alone (9.9% versus 24.6%, P = .0041) and between patients with affected middle cerebral and internal carotid arteries (7.0% versus 24.2%, P = .0002). The lowest apparent diffusion coefficient ratio was associated with the time to recombinant tissue plasminogen activator injection.

CONCLUSIONS

Minimum apparent diffusion coefficient ratios in Alberta Stroke Program Early CT Score regions are useful in predicting therapeutic effect.

Low-dose versus standard-dose intravenous alteplase for octogenerian acute ischemic stroke patients: A multicenter prospective cohort study

BACKGROUND AND PURPOSE

The optimal dose of alteplase for acute ischemic stroke among geriatric patients is unclear. We aimed to assess the efficacy and safety of a low-dose (0.6 mg/kg) and standard-dose (0.9 mg/kg) alteplase for varying severity of Asian geriatric stroke patients.

METHODS

The favorable functional outcome on day 90 after stroke onset, and the symptomatic intracranial hemorrhage (SICH) rate following 24-36 h of intravenous alteplase were measured. The baseline NIHSS of 4-8, 9-13, ≥14 were defined as mild, moderate, and high severity, respectively.

RESULTS

Totally, 249 geriatric patients treated with low-dose (n = 108) and standard-dose (n = 141) alteplase. Compared to standard-dose alteplase, low-dose alteplase had decrease in favorable functional outcome (22.2% versus 34.8%), and no difference in SICH rates was observed. For mild severity patients, the mortality was significantly increased with standard-dose alteplase (the NNT/NNH = 22.9/8.0 for mild severity, the NNT/ NNH = 15.0/14.7 for moderate severity, and the NNT/NNH = 13.5/19.6 for high severity).

CONCLUSIONS

Standard-dose and low-dose alteplase were comparable in reducing major disability, but low-dose alteplase for mild stroke showed much reduced mortality on day 90 for octogenarians.

The safety and efficacy of tPA intravenous thrombolysis for treating acute ischemic stroke patients with a history of cerebral hemorrhage

Alteplase (tPA) intravenous thrombolysis is an effective treatment for acute ischemic stroke (AIS) when administered within 4.5 h of initial stroke symptoms. Here, its safety and efficacy were evaluated among AIS patients with a previous history of cerebral hemorrhage. Patients who arrived at the hospital within 4.5 h of initial stroke symptoms and who were treated with tPA intravenous thrombolysis or conventional therapies were analyzed. The 90-day modified Rankin scale (90-d mRS) was used alongside mortality and incidence of symptomatic intracerebral hemorrhage (SICH) rates to evaluate the curative effect of these therapies. Among 1,694 AIS patients, 805 patients were treated with intravenous thrombolysis, including patients with (n=793) or without (n=12) a history of cerebral hemorrhage, and the rate of incidence of SICH significantly differed between them (8.3 vs 4.3%, P=0.039). No significant difference was found in 90-d mRS measurements (41.7 vs 43.6%, P=0.530) and 90-d mortality rates (8.3 vs 6.5%, P=0.946). A total of 76 AIS patients with a history of cerebral hemorrhage received tPA thrombolytic therapy (n=12) or conventional therapy (n=64), and a significant difference was noted in the 90-d mRS scores between the two groups (41.7 vs 23.4%, P=0.029), while no significant difference was found in SICH measurements (8.3 vs 4.6%, P=0.610) and 90-d mortality rates (8.3 vs 9.4%, P=0.227). A history of cerebral hemorrhage is not an absolute contraindication for thrombolytic therapy; tPA intravenous thrombolysis does not increase SICH measurements and mortality rates in patients with a history of cerebral hemorrhage, and they may benefit from thrombolytic therapy.

Thromboembolic Complications Following Tissue Plasminogen Activator Therapy in Patients of Acute Ischemic Stroke - Case Report and Possibility for Detection of Cardiac Thrombi

Many reports focus on the probability of intracranial hemorrhage as a complication after recombinant tissue plasminogen activator (rt-PA) therapy. However, thromboembolic complications are not well discussed. We experienced a case in which severe thromboembolic complications occurred in the right radial and right ulnar artery. Arterial fibrillation was observed in this case. If multiple thrombi exist in the atrium or ventricle, multiple small embolic particles may appear following thrombolytic therapy, and that may be a potential risk of secondary thromboembolic complications due to incomplete dissolution of thrombi. Transesophageal echocardiography is a standard method to detect intracardiac sources of emboli in the case of arterial fibrillation. Transesophageal echocardiography is, however, an invasive method for patients with ischemic stroke during rt-PA therapy. High resolution enhanced CT could be a useful tool and may be a reliable alternative to transthoracic echocardiography. Careful assessment of thromboembolic complications following rt-PA therapy in patients with arterial fibrillation is needed. In this case report and mini review, we would like to discuss about the accurate diagnostic methods to detect cardiac or undetermined embolic sources and provide expedited stroke care. These embolic sources may be more readily discovered during rt-PA therapy within the limited therapeutic time window.

Increased resistance to tissue plasminogen activator-induced fibrinolysis in healthy subjects from Thailand

: There is significant variability in blood coagulation among world populations. In particular, there may exist important differences in regulation of the fibrinolytic system in Asian populations that contribute to diseases of thrombosis and hemostasis. To investigate this issue, we compared fibrinogen concentration, plasma clot formation, and fibrinolytic resistance of healthy Asian subjects from Hat Yai, Songkhla, Thailand (Thai) vs. healthy North American subjects from Seattle, Washington, USA (SEA). Citrated plasma samples were obtained from healthy adult volunteers. Fibrinogen concentration was measured in plasma by the method of Clauss to examine for baseline differences of fibrinogen concentration. Samples were then standardized to 2.8 mg/ml fibrinogen using physiological buffer for each sample prior to fibrinolytic testing using rotational thromboelastometry (ROTEM) to examine for differences of clot lysis not attributable to fibrinogen concentration alone. Clot lysis was examined with ROTEM extrinsic pathway activation in the presence of 0, 0.5, and 1.0 μg/ml of tissue plasminogen activator (tPA). Two-way repeated measures analysis of variance was used to determine the effects of tPA and study group on ROTEM parameters. N = 49 Thai samples were compared with N = 58 SEA samples. Mean (SD) fibrinogen concentration was significantly increased for the Thai group at 4.03 (0.79) mg/ml vs. the SEA group at 3.66 (0.70) mg/ml (t test P = 0.014). After standardization of all samples to equivalent fibrinogen concentration, there were no differences in clot formation between groups without tPA. There was a significant effect of increasing tPA concentration on all ROTEM parameters except for clotting time. There were significant individual differences for amplitude at 10 min and lysis onset time, where amplitude at 10 min was significantly increased and lysis onset time was significantly prolonged for Thai vs. SEA at tPA concentrations of 0.5 and 1.0 μg/ml. Variability in thrombosis and hemostasis in Asians vs. other populations is likely to involve differences of fibrinogen concentration and regulation of clot lysis.

Consensus Guides on Stroke Thrombolysis for Anticoagulated Patients from Japan: Application to Other Populations

Development of direct oral anticoagulants and their antidotes has led to the need to reconsider the eligibility of acute stroke patients who have been taking oral anticoagulants for intravenous thrombolysis. Officially authorized Japanese guidelines on this issue were revised twice at the time of approval for clinical use of direct oral anticoagulants and idarucizumab, a specific reversal agent for dabigatran. A unique recommendation in the latest Japanese clinical guides was that thrombolysis can be recommended if the time of the last dose of direct oral anticoagulants exceeds 4 hours and if commonly available anticoagulation markers are normal or subnormal, i.e., international normalized ratio of prothrombin time <1.7 and activated partial thromboplastin time <1.5 times the baseline value (≤40 seconds only as a guide). These criteria are partly supported by the findings of domestic multicenter and single-center surveys that symptomatic or asymptomatic intracranial hemorrhage following thrombolysis was rare under the conditions of the criteria. Even for dabigatran users, stroke thrombolysis can be considered without pretreatment by idarucizumab if patients meet the above criteria. If not, direct mechanical thrombectomy can be considered without pretreatment by idarucizumab or thrombolysis, and use of idarucizumab, followed immediately by thrombolysis, can be considered only when thrombectomy cannot be quickly performed. These clinical guides are practical and to some extent economical, but they have some limitations, including lack of corroborating information from sufficient numbers of relevant cases. The guides will be further modified based on the results of future research.

Fixed Dose IV rt-PA and Clinical Outcome in Ischemic Stroke Patients With Body Weight >100 kg: Pooled Data From 3 Randomized Clinical Trials

BACKGROUND AND PURPOSE

The ASA/AHA guidelines recommend a fixed dose of 90 mg of intravenous (IV) recombinant tissue plasminogen activator (rt-PA) for acute stroke patients weighing more than 100 kg. We aimed to determine if body weight >100 kg (and receiving <0.9 mg/kg dose) independently influence patient clinical outcomes following IV rt-PA treatment.

METHODS

We pooled data from IV rt-PA treatment arms from 3 randomized controlled clinical trials; NINDS IV rt-PA study, Interventional Management of Stroke 3 and ALIAS (part 1 and 2). Baseline characteristic, hospital course and 90-day mRS were compared between patients >100 kg and those ≤100 kg body weight. Multivariate logistic regression model was used to identify the independent effect of >100 kg body weight on favorable 90-day outcome (defined as mRS 0-2), the rate of symptomatic intracranial hemorrhage, and poor 90-day outcome (mRS 4-6).

RESULTS

Among 873 patients treated with IV rt-PA, a total of 105 (12%) subjects had body weight >100 kg. Compared with patients having ≤100 kg body weight, the rate of favorable outcome at 90 days was not significantly different among patients with >100 kg body weight (OR: 0.99; 95% CI: 0.91-1.01; p=0.91) , after adjusting for potential confounders. The ordinal analysis did not show any significant shift in the distribution of 90-day mRS score in patients with >100 kg body weight (OR, 0.93; 95% CI, 0.64-1.37; P = 0.74) CONCLUSIONS: There was no reduction in the rate of favorable outcome in patients with acute ischemic stroke with body weight >100 kg who received <0.9 mg/kg dose of IV rt-PA. Our results support the current recommendations in the ASA/AHA guidelines.

Safety and Efficacy of Intravenous Low-Dose Alteplase in Relative Contraindication Patients with Acute Ischemic Stroke

OBJECT

The purpose of this study was to investigate the safety and efficacy of intravenous low-dose alteplase for acute ischemic stroke patients with relative contraindications.

METHODS

The consecutive series of patients admitted within 4.5 hours of ischemic stroke onset between September 2012 and April 2017 were retrospectively evaluated. A good outcome at 90 days and symptomatic intracerebral hemorrhage were evaluated to determine the association with intravenous low-dose alteplase, especially in the presence of relative contraindications.

RESULTS

Intravenous low-dose alteplase was administered to 219 of 315 patients (70%). A significantly higher number of patients treated with intravenous low-dose alteplase achieved a good outcome compared with those treated without alteplase (60% versus 44%; P = .014). The incidence of symptomatic intracerebral hemorrhage was not significantly different between the treatment groups. Multivariable logistic regression analysis of good outcome revealed that the significant independent factors were age of 81 years or older (odds ratio, .33; 95% confidence interval, .18-.60), National Institutes of Health Stroke Scale (NIHSS) of 4 or less (compared with NIHSS, 5-25; odds ratio, 3.3; 95% confidence interval, 1.8-6.4), modified Rankin scale score of 1 before stroke (odds ratio, .32; 95% confidence interval, .14-.73), and large changes on first brain imaging (odds ratio, .16; 95% confidence interval, .058-.44). Even with these relative contraindications, intravenous low-dose alteplase was still associated with good outcome (odds ratio, 3.1; 95% confidence interval, 1.6-5.8).

CONCLUSIONS

Intravenous low-dose alteplase treatment can be safe and effective in relative contraindication patients with acute ischemic stroke.

Intravenous thrombolysis for acute ischemic stroke: a bridge between two centuries

INTRODUCTION

Intravenous tissue-plasminogen activator (tPA) remains the only approved systemic reperfusion therapy suitable for most patients presenting timely with acute ischemic stroke. Accumulating real-word experience for over 20 years regarding tPA safety and effectiveness led to re-appraisal of original contraindications for intravenous thrombolysis (IVT). Areas covered: This narrative review focuses on fast yet appropriate selection of patients for safe administration of tPA per recently expanded indications. Novel strategies for rapid patient assessment will be discussed. The potential for mobile stroke units (MSU) that shorten onset-to-needle time and increase tPA treatment rates is addressed. The use of IVT in the era of non-vitamin K antagonist oral anticoagulants (NOACs) is highlighted. The continuing role of IVT in large vessel occlusion (LVO) patients eligible for mechanical thrombectomy (MT) is discussed with regards to 'drip and ship' vs. 'mothership' treatment paradigms. Promising studies of penumbral imaging to extend IVT beyond the 4.5-hour window and in wake-up strokes are summarized. Expert commentary: This review provides an update on the role of IVT in specific conditions originally considered tPA contraindications. Novel practice challenges including NOAC's, MSU proliferation and bridging therapy (IVT&MT) for LVO patients, and the potential extension of IVT time-window using penumbral imaging are emerging as safe and potentially effective IVT applications.

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.

Acute pancreatitis is a very rare comorbidity of acute ischemic stroke

Background: Although acute pancreatitis is listed among the exclusion criteria for the administration of recombinant tissue plasminogen activator according to the Japanese Guideline for the Management of Stroke, the co-occurrence of acute pancreatitis and acute ischemic stroke has not been investigated. The present study aimed to assess the incidence rate of acute pancreatitis in patients with acute ischemic stroke.

Methods: This study consecutively enrolled all patients with ischemic stroke admitted to the Department of Neurology, JA Toride Medical Center between April 2014 and March 2016. Diagnosis of acute pancreatitis was made according to the revised Atlanta Classification of Acute Pancreatitis. We retrospectively analyzed serum amylase activity and the frequency of acute pancreatitis as a comorbidity of ischemic stroke.

Results: A total of 411 ischemic stroke patients were included. Serum amylase activity was measured for 364 patients, 27 of whom presented with amylase activity exceeding the upper limit of normal. In two patients with serum amylase activity greater than three times-fold the upper limit of normal, computed tomography or transabdominal ultrasonography showed no characteristic findings of acute pancreatitis. No patient in the cohort met the diagnostic criteria for acute pancreatitis.

Conclusions: Acute pancreatitis is a very rare comorbidity of acute ischemic stroke.

Effects of a school-based stroke education program on stroke-related knowledge and behaviour modification-school class based intervention study for elementary school students and parental guardians in a Japanese rural area

OBJECTIVES

This study aimed to determine the effect of a stroke education programme on elementary school students and their parental guardians in a rural area in Japan that has high stroke mortality.

DESIGN

School class based intervention study.

SETTING

Eleven public elementary schools in Tochigi Prefecture, Japan.

PARTICIPANTS

268 students aged 11-12 years and 267 parental guardians.

INTERVENTIONS

Students received lessons about stroke featuring animated cartoons and were instructed to communicate their knowledge about stroke to their parental guardians using material (comic books) distributed in the lessons. Stroke knowledge (symptoms, risk factors and attitude towards stroke) and behavioural change for risk factors were assessed at baseline, immediately after the programme and at 3 months. We also evaluated behavioural change for risk factors among parental guardians.

RESULTS

The percentage of students with all correct answers for stroke symptoms, risk factors and the recommended response to stroke was significantly increased at 3 months P<0.001). We observed a significant increase in the percentage of guardians who chose all correct symptoms (P<0.001: 61.0% vs 85.4%) and risk factors (P<0.001: 41.2% vs 59.9%) at 3 months compared with baseline. The percentage of parental guardians with a high behavioural response to improving risk factors was significantly increased at 3 months compared with baseline (P<0.001).

CONCLUSIONS

In a rural population with high stroke mortality, stroke education can improve knowledge about stroke in elementary school students and their parental guardians.

ETHICS AND DISSEMINATION

We conducted the intervention as a part of compulsory education; this study was not a clinical trial. This study was approved by the Ethics Committee of the National Cerebral and Cardiovascular Center (M27-026).

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.

Clinical features of patients who died within 24 h after admission to a stroke care center

Objective In Japan, stroke care is provided through medical cooperation and standardized treatment. However, various factors affect mortality in the hyperacute phase. The present study investigated factors associated with death within 24 h after admission for acute stroke. Methods Among 2335 patients admitted within 24 h after stroke onset from 1 January 2007 to 31 December 2012, a total of 139 deaths occurred. Forty-eight deaths occurred within 24 h after admission. We retrospectively examined the clinical features of these 48 patients. Results The overall mortality rate was 6.0%. When the initial 72-h period was divided into ≤24 h (Period I), >24 to 48 h (Period II), and >48 to 72 h (Period III), deaths were significantly more frequent in Period I than in the other two periods. The frequency of intracerebral haemorrhage (ICH) was also significantly higher in Period I than in the other two periods. Factors significantly associated with death from ICH were systolic blood pressure, hematoma volume, and surgery. Conclusion The mortality rate was low among patients with stroke transported to the authors' medical center within 24 h of onset. Blood pressure management and the timing of determining indications for surgery are important factors in acute haemorrhagic stroke care.

Prediction of thrombus resolution after intravenous thrombolysis assessed by CT-based thrombus imaging

The degree of thrombus resolution directly indicates the effectiveness of a thrombolytic drug. We investigated the degree of thrombus resolution and factors associated with thrombus resolution after intravenous (IV) recombinant tissue plasminogen activator (rt-PA) using thin-section noncontrast computed tomography (NCT). Thin-section NCTs were performed before and immediately after IV rt-PA infusion in acute stroke patients. The thrombus volume and Hounsfield unit were measured using three-dimensional imaging software. Immediate recanalisation was assessed immediately after IV rt-PA infusion using CT angiography. During a three-year study period, 130 patients were prospectively enrolled. On baseline thin-section NCT, no thrombi were found in 30 patients (23%). Among the 100 patients with confirmed thrombus, the median volume decreased by 20% on the follow-up NCT. The thrombus was completely resolved in 8%. Of note, an increase in thrombus volume was observed in 20 patients. Independent predictors of thrombus resolution were total rt-PA dose, thrombus location in the M2 segment of the middle cerebral artery, and time from baseline to follow-up NCT. Thrombus resolution increased by 9% per each 10-mg increase in rt-PA (p = 0.045). Immediate complete recanalisation was achieved in 12% of patients. Total dose of rt-PA was independently associated with complete recanalisation [odds ratio [OR] 4.52, 95% confidence interval [CI] 1.345–15.184) and good functional outcome at three months (modified Rankin scale score <3, OR 2.34, 95% CI 1.104–4.962). In conclusion, rt-PA dose was associated with the degree of thrombus resolution, immediate complete recanalisation, and good outcome at three months. CT-based thrombus imaging may be helpful in determining thrombolysis effectiveness.

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.

Characteristics, management and response to alteplase in China versus non-China participants of the ENCHANTED trial

Background

The characteristics of patients with acute ischaemic stroke (AIS) and their management vary across regions, which may influence outcomes. We examined for differential patterns of outcome between China and non-China participants of the ENhanced Control of Hypertension And Thrombolysis strokE stuDy (ENCHANTED), which tested different alteplase doses in AIS.

Methods

ENCHANTED was an international, multicentre, open, blinded-endpoint trial of the effects of low-dose (0.6 mg/kg) versus standard-dose (0.9 mg/kg) intravenous alteplase on 90-day disability outcomes and symptomatic intracerebral haemorrhage (sICH) in 3310 patients with AIS.

Results

Participants (n=1419, 48%) in China were younger, and more often male, hypertensive and with prior stroke and coronary artery disease, but less likely to have atrial fibrillation and use antihypertensive, antithrombotic and lipid-lowering agents, compared with non-China patients with AIS. Although China participants had more AIS due to large artery occlusion, were treated later and had differing ancillary management, there was no significant difference in 90-day modified Rankin scale scores 2–6 (55.6% vs 47.8%; OR, adjusted for baseline and management factors 0.87 (95% CI 0.71 to 1.07; p=0.20)) and risk of sICH (Safe Implementation of Thrombolysis in Stroke-Monitoring Study criteria: 1.4% vs 1.8%; p=0.12) compared with non-China participants. There was no heterogeneity in the treatment effects of low-dose versus standard-dose alteplase between China and non-China participants.

Conclusion

Patients with AIS recruited to the ENCHANTED trial in China had similar outcomes in response to thrombolysis treatment despite significantly differing demographic, clinical and management factors to patients with AIS in other regions.