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

[Efficacy of tissue plasminogen activator in older patients]

AIM

To evaluate the efficacy, outcome, and side effects of tissue plasminogen activator for cerebral infarction in patients aged 75 years or older.

METHODS

Subjects consisted of 30 patients who had been treated with tissue plasminogen activator between October, 2005 and March 2009, in Shimane University Hospital. We divided the patients into two groups: those less than 75 years old and those 75 years old and older, and evaluated the pattern of disease, therapeutic efficacy, side effects of bleeding, and factors affecting the modified Rankin Scale on discharge.

RESULTS

There was no significant difference between groups in the improvement level of NIH Stroke Scale (p=0.66), but modified Rankin Scale 2 or lower patients on discharge were significantly fewer (p=0.02). Multivariate analysis found that age was a factor in significant outcome deterioration (p=0.04, OR1.2). In the older patient group, there were significantly more unfavorable outcomes with anterior infarction. However, there was no significant difference between groups in outcome in patients with ASPECTS-DWI (Alberta Stroke Programme Early CT Score-Diffusion Weight Imaging) > or =8. There was no difference in the rate of hemorrhagic side effect between the two groups.

CONCLUSION

We can expect effects similar to those in patients younger than 75 years if the ischemic lesions of older patients are narrow when coming to the hospital.

[Intravenous rt-PA therapy for acute ischemic stroke: efficacy and limitations]

After the success of the 1995 National Institutes of Neurological Disorders and Stroke (NINDS) study using intravenous (i.v.) recombinant tissue plasminogen activator (rt-PA, alteplase) within 3 hours in acute stroke, this therapy was approved worldwide and has been a standard therapy for acute stroke patients. In Japan, IV alteplase at a dose of 0.6 mg/kg was approved in 2005 after a multicenter study using this low dose of alteplase (Japan Alteplase Clinical Trial [J-ACT]). IV rt-PA can drastically improve stroke outcomes. However, more than half of treated patients are not independent in the chronic stage. In addition, the therapeutic time window was so limited that many stroke patients do not have a chance to receive the therapy. In 2008, European Cooperative Acute Stroke Study III showed that IV rt-PA administered between 3 and 4.5 hours after stroke onset significantly improved clinical outcomes in stroke patients; the success resulted in the renewal of recommendation in guidelines in Europe, Canada, and the United States. Several therapeutic strategies, including endovascular therapy, sonothrombolysis, and neuroprotective therapy, may improve the efficacy of IV rt-PA.

Arterial Occlusion Sites on Magnetic Resonance Angiography Influence the Efficacy of Intravenous Low-Dose (0·6 mg/kg) Alteplase Therapy for Ischaemic Stroke

Aims

To determine the predictors of efficacy, including magnetic resonance imaging information, for low-dose intravenous alteplase therapy for stroke patients.

Methods

Seventy-eight patients were prospectively enrolled in a single Stroke Unit (SU) receiving alteplase at a dose of 0·6 mg/kg during the initial 27 months after its approval in Japan. Ischaemic changes and vascular lesions were identified using computed tomography, diffusion-weighted magnetic resonance imaging, and magnetic resonance angiography. Early ischaemic signs were assessed using the Alberta Stroke Program Early CT Score.

Results

The median baseline National Institutes of Health Stroke Scale score of 78 patients was 12. In 19 patients (24%), the National Institutes of Health Stroke Scale score improved by ≥8 points at 24 h. After multivariate adjustment, occlusion at the internal carotid artery (odds ratio 11·82, 95% confidence interval 1·73–142·74), Alberta Stroke Program Early CT Score on diffusion-weighted imaging ≤6 (15·23, 1·88–351·50), and a lower National Institutes of Health Stroke Scale score (1·24, 1·08–1·47, per 1-point decrease) were inversely correlated with early improvement. Four patients (5%) had symptomatic intracranial haemorrhage. At 3 months, 76 patients (98%) survived, and 36 of 78 patients (46%) overall, but only two of 19 patients (11%) with internal carotid artery occlusion, had a favourable functional outcome, corresponding to a modified Rankin scale score 1. After multivariate adjustment, internal carotid artery occlusion (odds ratio 15·84, 95% confidence interval 3·12–128·69) and Alberta Stroke Program Early CT Score on diffusion-weighted imaging ≤6(15·62, 1·78–410·12) were independent predictors of poor outcome.

Conclusions

Intravenous alteplase therapy at a dose of 0·6 mg/kg resulted in a relatively good overall outcome when compared with outcomes reported by western studies using an alteplase dose of 0·9 mg/kg. However, patients with occlusion at the internal carotid artery did not respond to this low-dose alteplase therapy.

Routine Use of Intravenous Low-Dose Recombinant Tissue Plasminogen Activator in Japanese Patients

Background and Purpose— A retrospective, multicenter, observational study was conducted to document clinical outcomes and to identify outcome predictors in patients treated with low-dose intravenous recombinant tissue plasminogen activator (0.6 mg/kg alteplase), which was approved in Japan in 2005, within 3 hours of stroke onset.

Methods— Consecutive patients with stroke treated with recombinant tissue plasminogen activator in 10 Japanese stroke centers were included.

Results— A total of 600 patients (377 men, 72±12 years old) were studied. Median National Institutes of Health Stroke Scale scores decreased from 13 before recombinant tissue plasminogen activator to 8 at 24 hours later. Symptomatic intracerebral hemorrhage within 36 hours with a ≥1-point increase from the baseline National Institutes of Health Stroke Scale score developed in 23 patients (3.8%; 95% CI, 2.6% to 5.7%). At 3 months, 43 patients had died (7.2%; 5.4% to 9.5%), and 199 patients (33.2%; 29.5% to 37.0%) had a modified Rankin Scale score ≤1. Analysis of 399 patients with a premorbid modified Rankin Scale score ≤1 who met the criteria of the European license (≤80 years old, an initial National Institutes of Health Stroke Scale score ≤24, etc) showed that 40.6% (35.9% to 45.5%) had a 3-month modified Rankin Scale score ≤1. After multivariate adjustment, younger age, lower initial National Institutes of Health Stroke Scale score, absence of internal carotid artery occlusion, higher Alberta Stroke Program Early CT Score on CT, and absence of intravenous antihypertensives just before recombinant tissue plasminogen activator were independently related to a 3-month modified Rankin Scale score ≤1. Congestive heart failure and hyperglycemia were independently related to mortality.

Conclusions— Three-month outcomes of patients receiving low-dose intravenous recombinant tissue plasminogen activator therapy in the present study were similar to those from postmarketing surveys using 0.9 mg/kg alteplase.

Thrombolysis for acute ischaemic stroke

BACKGROUND

The majority of strokes are due to blockage of an artery in the brain by a blood clot. Prompt treatment with thrombolytic drugs can restore blood flow before major brain damage has occurred and could improve recovery after stroke. Thrombolytic drugs, however, can also cause serious bleeding in the brain, which can be fatal. One drug, recombinant tissue plasminogen activator (rt-PA), is licensed for use in highly selected patients within three hours of stroke.

OBJECTIVES

To assess the safety and efficacy of thrombolytic agents in patients with acute ischaemic stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched October 2008), MEDLINE (1966 to October 2008) and EMBASE (1980 to October 2008). We contacted researchers and pharmaceutical companies, attended relevant conferences and handsearched pertinent journals.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

Two review authors applied the inclusion criteria and extracted data. We assessed trial quality. We verified the extracted data with the principal investigators of all major trials. We obtained both published and unpublished data if available.

MAIN RESULTS

We included 26 trials involving 7152 patients. Not all trials contributed data to each outcome. The trials tested urokinase, streptokinase, recombinant tissue plasminogen activator, recombinant pro-urokinase or desmoteplase. Four trials used intra-arterial administration, the rest used the intravenous route. Most data come from trials that started treatment up to six hours after stroke; three trials started treatment up to nine hours and one small trial up to 24 hours after stroke. About 55% of the data (patients and trials) come from trials testing intravenous tissue plasminogen activator. Very few of the patients (0.5%) were aged over 80 years. Many trials had some imbalances in key prognostic variables. Several trials did not have complete blinding of outcome assessment. Thrombolytic therapy, mostly administered up to six hours after ischaemic stroke, significantly reduced the proportion of patients who were dead or dependent (modified Rankin 3 to 6) at three to six months after stroke (odds ratio (OR) 0.81, 95% confidence interval (CI) 0.73 to 0.90). Thrombolytic therapy increased the risk of symptomatic intracranial haemorrhage (OR 3.49, 95% CI 2.81 to 4.33) and death by three to six months after stroke (OR 1.31, 95% CI 1.14 to 1.50). Treatment within three hours of stroke appeared more effective in reducing death or dependency (OR 0.71, 95% CI 0.52 to 0.96) with no statistically significant adverse effect on death (OR 1.13, 95% CI 0.86 to 1.48). There was heterogeneity between the trials in part attributable to concomitant antithrombotic drug use (P = 0.02), stroke severity and time to treatment. Antithrombotic drugs given soon after thrombolysis may increase the risk of death.

AUTHORS' CONCLUSIONS

Overall, thrombolytic therapy appears to result in a significant net reduction in the proportion of patients dead or dependent in activities of daily living. This overall benefit was apparent despite an increase both in deaths (evident at seven to 10 days and at final follow up) and in symptomatic intracranial haemorrhages. Further trials are needed to identify which patients are most likely to benefit from treatment and the environment in which thrombolysis may best be given in routine practice.

M1 Susceptibility Vessel Sign on T2* as a Strong Predictor for No Early Recanalization After IV-t-PA in Acute Ischemic Stroke

Background and Purpose— In acute stroke patients treated with intravenous tissue plasminogen activator (t-PA), early recanalization of occluded arteries can improve the clinical outcome. The magnetic susceptibility effect of deoxygenated hemoglobin in red thrombi can present as hypointense signals on T2*-weighted gradient echo imaging. We investigated whether the gradient echo imaging M1 susceptibility vessel sign (M1 SVS) can predict no early recanalization after t-PA infusion.

Methods— Patients with internal carotid artery and M1 occlusion were prospectively studied. MRI studies, including DWI, T2*, and MRA, were performed before and within 30 minutes and 24 hours after t-PA infusion. The NIHSS score was obtained before and 7 days after t-PA administration. The relationship between the presence of the M1 SVS and no early recanalization and patient outcome was examined.

Results— A total of 48 patients (29 men; mean age, 74.6±11.2 years) were enrolled. M1 SVS was present in 13 (27.1%) patients and absent in 35 (72.9%) patients. There were no significant differences in clinical characteristics between the 2 groups. Follow-up MRA within 30 minutes after t-PA infusion revealed that 20 (57.1%) of the 35 patients without the M1 SVS had early recanalization, but that none of the 13 patients with the M1 SVS had early recanalization ( P =0.0002). Seven days after t-PA infusion, dramatic improvement was more frequently observed in patients without the M1 SVS (51.4%) than in those with the M1 SVS (0%, P =0.0007).

Conclusion— The M1 SVS on T2* appears to be a strong predictor for no early recanalization after t-PA therapy.

Clinical outcomes of acute stroke patients with atrial fibrillation

Evaluation of: Kazumi K, Yasuyuki I, Kensaku S, Takeshi I, Shinji Y, Junya A. IV-tPA therapy in acute stroke patients with atrial fibrillation. J. Neurol. Sci. 276(1-2), 6-8 (2009). Stroke is the leading cause of disability and the second most common cause of death worldwide. The care and treatment of stroke patients have evolved over the last two decades, with increasing use of thrombolysis (e.g., intravenous tissue plasminogen activator in acute stroke patients), which has improved survival and recovery following stroke. The article under evaluation offers a greater insight into the relationship of clinical outcome of stroke and atrial fibrillation after tissue plasminogen activator infusion.

Unruptured Cerebral Aneurysm Detected after Intravenous Tissue Plasminogen Activator for Stroke

Therapeutic guidelines of intravenous thrombolysis with tissue plasminogen activator (tPA) for hyperacute ischemic stroke are very strict. Because of potential higher risk of bleeding complications, the presence of unruptured cerebral aneurysm is a contraindication for systemic thrombolysis with tPA. According to the standard CT criteria, a 66-year-old woman who suddenly developed aphasia and hemiparesis received intravenous tPA within 3 h after ischemic stroke. Magnetic resonance angiography during tPA infusion was performed and the presence of a small unruptured cerebral aneurysm was suspected at the anterior communicating artery. Delayed cerebral angiography confirmed an aneurysm with a size of 7 mm. The patient did not experience any adverse complications associated with the aneurysm. Clinical experiences of this kind of accidental off-label thrombolysis may contribute to modify the current rigid tPA guidelines for stroke.

Efficacy of the free radical scavenger, edaravone, for motor palsy of acute lacunar infarction

OBJECTIVE

Free radicals are important in causing neural cell injury during cerebral infarction. Although there was a randomized, placebo-controlled, double-blind study at multiple centers in Japan showing the efficacy of the free radical scavenger, edaravone, in acute cerebral infarction, to date the clinical studies are few. This study investigated the effect of edaravone on the outcome of patients with acute lacunar infarction.

METHODS

We retrospectively evaluated 124 consecutive patients with first-ever acute lacunar infarctions who were admitted to our hospital within 24 hours after the onset between January 2004 and June 2007. Of these, 59 patients received both edaravone and conventional therapy (edaravone group), and the other 65 underwent conventional therapy only (non-edaravone group). There was no significant difference in patients' baseline characteristics in the two groups. The clinical outcome was assessed by the National Institutes of Health Stroke Scale (NIHSS).

RESULTS

The reduction of NIHSS scale during hospitalization (1.5+/-1.0 vs. 1.0+/-1.1; p = 0.007), especially that of the motor palsy scale (1.0+/-1.0 vs. 0.5+/-1.0; p = 0.006) was significantly larger, and the percentage of patients with a favorable outcome (NIHSS at discharge < or =1) (91.5% vs. 78.5%; p = 0.044) was significantly better in the edaravone group.

CONCLUSION

Edaravone improves the outcomes of patients with acute lacunar infarction, especially motor palsy, without regard to the conventional therapy performed concomitantly.

[New era has begun since the approval of thrombolytic therapy for acute ischemic stroke in Japan]

Japan Alteplase Clinical Trial (J-ACT), a prospective multicenter clinical trial, demonstrated good clinical outcome in patients treated with 0.6 mg/kg of alteplase, being similar to that with 0.9 mg/kg of alteplase in the National Institute of Neurological Disorders and Stroke (NINDS) study. On that basis, intravenous aplteplase therapy was approved in Japan in October, 2005. This therapy resulted in better efficacy and similar safety in our stroke care unit (SCU) as compared to J-ACT or other clinical studies performed outside Japan. Our nation-wide survey demonstrated that the approval of the therapy resulted in dramatic changes in the processes of management for acute stroke patients. Preliminary results of the post-marketing surveillance study of alteplase in Japan suggested similar efficacy and safety profiles of the therapy to those reported by a European study, Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST). There are several limitations and problems in the therapy that will be overcome by new therapeutic strategies including the development of new-generation therombolytic agents having longer therapeutic time window, applications of magnetic resonance imaging techniques, and combination therapies with neuroprotective agents, sonothrombolysis, intraarterial application of the agent, or mechanical thrombectomy.

[Diagnosis and management for acute ischemic stroke]

The management for acute stroke has been changed greatly in Japan. Because use of intravenous administration of tissue plasminogen activator (IV-t-PA) for acute brain infarction within 3 hours of onset has been approved by Japanese government from October, 2005. Now, if acute stroke patient arrivals at hospital within 3 hours of onset, we consider that such patients should be treated with t-PA therapy. The accurate diagnosis should be made by systematic evaluation using CT/MRI, neurosonology including transcranial Doppler, carotid echography, and echocardiography (TEE and TTE), SPECT, and angiography. In particular, it is important to assess the arteries from heart and brain. The grad A for treatment of acute stroke is recommended as IV-t-PA therapy, aspirin administration within 48 hours of stroke onset, and the management in stroke unit. In particular, stroke unit can improve functional outcome and to reduce the length of hospital stay. The evidence directing therapy for acute stroke is changing rapidly.

Impact of the approval of intravenous recombinant tissue plasminogen activator therapy on the processes of acute stroke management in Japan: the Stroke Unit Multicenter Observational (SUMO) Study

BACKGROUND AND PURPOSE

The Ministry of Health, Labor, and Welfare of Japan approved the use of recombinant tissue-type plasminogen activator (rt-PA) for the treatment of acute ischemic stroke in October 2005. The impact of the regulatory approval of rt-PA on the processes of acute stroke management was examined.

METHODS

A prospective, multicenter, observational study was conducted between December 2004 and December 2005 in 84 Japanese institutes, including 24 institutes with a stroke unit. We enrolled 4620 consecutive patients who were hospitalized within 72 hours after the onset of completed ischemic stroke; 1089 of them were hospitalized after rt-PA was approved. The patients' characteristics and the processes of stroke management were compared before and after rt-PA approval.

RESULTS

Age, gender, stroke subtype, time from onset to hospital visit, and National Institutes of Health Stroke Scale score on admission were similar between the 2 periods. With approval, the percentage of patients treated with intravenous rt-PA therapy increased from 0.7% to 2.6% (P<0.001). The rate increased from 0.9% to 5.2% in institutes with a stroke unit (P<0.001) but did not increase in other institutes (P=0.587). Within 24 hours of stroke onset, conventional MRI (P=0.003), diffusion-weighted MRI (P<0.001), magnetic resonance angiography (P=0.001), carotid ultrasound (P=0.004), measurement of prothrombin time or activated partial thromboplastin time (P=0.034), and measurement of blood sugar (P=0.015) were performed more frequently after rt-PA approval.

CONCLUSIONS

The present results indicate that the approval of intravenous rt-PA therapy resulted in dramatic changes in the processes of management for acute stroke patients.

The presence of a right-to-left shunt is associated with dramatic improvement after thrombolytic therapy in patients with acute ischemic stroke

BACKGROUND AND PURPOSE

The efficacy of pharmacological thrombolysis using tissue plasminogen activator depends on the relative fibrin content of the thrombus. We investigated whether patients with stroke with a right-to-left shunt (RLS), whose embolic source was associated with fibrin-rich thrombus formed in the venous system, were more likely to improve dramatically after thrombolytic therapy than those without RLS.

METHODS

Patients with acute stroke treated with tissue plasminogen activator were assessed prospectively to determine the clinical factors associated with "dramatic improvement" after tissue plasminogen activator administration. "Dramatic improvement" was defined as a >/=10-point reduction in the total National Institutes of Health Stroke Scale score or a total National Institutes of Health Stroke Scale score of 0 or 1 at 7 days. The presence of an RLS was determined using contrast transcranial Doppler within 6 hours of stroke onset.

RESULTS

Forty-four patients (26 males; mean age; 73.0+/-10.7 years; baseline National Institutes of Health Stroke Scale score,13.4+/-6.6) were enrolled. Twenty-one patients had dramatic improvement (D group). Contrast transcranial Doppler demonstrated an RLS in 17 (35.4%) patients. On multivariate logistic regression analysis using hyperlipidemia, atrial fibrillation, RLS, DWI-ASPECTS (>8), baseline National Institutes of Health Stroke Scale score (<10), and glucose (<120 mg/dL) as variables with a P<0.1 on univariate analysis, RLS (OR, 5.9; CI,1.3 to 27.3; P=0.022) was the only independent factor associated with dramatic improvement.

CONCLUSIONS

The presence of an RLS on contrast transcranial Doppler was an independent factor associated with dramatic improvement after tissue plasminogen activator administration.

Ultrasound Assisted Thrombolysis in Acute Ischaemic Stroke: Preliminary Experience in Singapore

Background and Aim: Intravenously-administered tissue plasminogen activator (IV-TPA) induces thrombolysis and remains the only FDA-approved therapy for acute ischaemic stroke. IV-TPA thrombolysis has been approved recently in Singapore for acute stroke. Continuous exposure of clot to 2-MHz pulsed-wave transcranial Doppler (TCD) ultrasound during IV-TPA infusion is known to augment thrombolysis. We aimed to determine the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore. Subjects and Methods: Consecutive patients with acute ischaemic stroke due to intracranial arterial-occlusions were treated with standard IV-tPA and continuously monitored with 2-MHz TCD according to the CLOTBUST-trial protocol. Arterial recanalisation was determined with Thrombolysis in Brain Ischemia (TIBI) flow-grading system. Safety and efficacy of ultrasoundassisted thrombolysis were assessed by rates of symptomatic intracranial haemorrhage (sICH) and functional recovery at 1 month, respectively. Results: Five consecutive patients (mean age 58 years, 3 men and 3 of Chinese ethnicity) were included. Mean time elapsed between symptom onset and presentation to emergency room was 98 minutes (range, 50 to 135 minutes) while the mean time interval between symptom onset to IV-TPA bolus was 144 minutes (range, 125 to 180 minutes). Partial or complete recanalisation with reduction in the stroke severity was noted in 4 out of the 5 patients during IV-TPA infusion (mean change in NIHSS = 4 points; range 2 to 8 points). None of our patients developed sICH while 4 patients demonstrated good functional outcome at 1 month. Conclusions: Our preliminary study demonstrates the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore. Continuous TCD-monitoring during IV-TPA infusion provides real-time information, enhances thrombolysis and improves functional outcomes in acute ischaemic stroke. Key words: Acute ischaemic stroke, Thrombolysis, Transcranial Doppler

Large Ischemic Lesions on Diffusion-Weighted Imaging Done Before Intravenous Tissue Plasminogen Activator Thrombolysis Predicts a Poor Outcome in Patients With Acute Stroke

Background and Purpose— MRI is useful for detecting early ischemic lesions before administration of tissue plasminogen activator in patients with hyperacute ischemic stroke. However, it is unclear whether early ischemic change seen on diffusion-weighted imaging (DWI) can be used to predict patient outcomes.

Methods— Consecutive patients with anterior circulation ischemic stroke treated with tissue plasminogen activator within 3 hours of stroke onset were prospectively studied. The National Institutes of Health Stroke Scale score was obtained before and 7 days after tissue plasminogen activator administration. MRI, including DWI, was done before tissue plasminogen activator thrombolysis. The relationship between the DWI Alberta Stroke Programme Early CT Score (ASPECTS) and patients’ outcomes was assessed.

Results— The subjects consisted of 49 consecutive patients with stroke (27 males; mean age, 72.9±10.3 years). The median (range) of the baseline DWI ASPECTS value was 9 (3–10). Dramatic improvement was seen in one of 8 patients with an ASPECTS ≤5 compared with 21 of 41 patients with a DWI ASPECTS >5 ( P =0.0592). On the other hand, worsening was noted more frequently in patients with a DWI ASPECTS ≤5 (3 of 8 patients) than in patients with an ASPECTS >5 (4 of 41 patients; P =0.0753). Bad outcome was seen more frequently in patients with a DWI ASPECTS ≤5 (6 of 8 patients) than in patients with a DWI ASPECTS >5 (2 of 41 patients; P <0.0001). Multivariate logistic regression analysis demonstrated that a DWI ASPECTS ≤5 was the only independent predictor of a bad outcome (OR, 33.4; 95% CI, 2.7 to 410.8; P =0.0062).

Conclusion— DWI ASPECTS appears to be a reliable tool for predicting bad outcome. Patients with a DWI ASPECTS >5 should be considered eligible for tissue plasminogen activator therapy.

[IV t-pA thrombolysis in acute stroke patients]

Intravenous administration of tissue plasminogen activator (t-PA) can improve clinical outcome in patients with acute ischemic stroke. In our country, use of t-PA for acute brain infarction within 3 hours of onset was approved by Japanese government from October, 2005. About 5,700 patients were treated with t-PA for these two years. Analysis of 2,484 patients (mean 70 years old, median NIHSS Score 15) showed that mRS 0-1 was 32%, the death was 20% and symptomatic brain hemorrhage was 5.2%. We had 63 patients (median 74 years old, median NIHSS score 14) treated with t-PA thrombolysis by November, 2007. Immediately after t-PA therapy 8 patients (12.7%) had dramatic recovery. On day 7 after t-PA therapy, excellent recovery was 49.2%, good recovery was 15.9%, and worsening was 12.7%. Within one hour after t-PA therapy, rate of recanalization for occluded arteries was 43.5%, which was strongly associated with excellent and good neurological recovery on day 7. Atrial fibrillation was an independent factor associated with no early recanalization. When we evaluated baseline DWI findings before t-PA infusion using DWI-ASPECTS and NIHSS score at day 7 after rt-PA therapy, bad outcome was seen more frequently in patients with an DWI ASPECTS < or = 5 (6 of 8 patients) than in patients with an DWI ASPECTS > 5 (2 of 41 patients; P < 0.0001). Patients with an ASPECTS-DWI > 5 should be considered eligible for t-PA therapy.

Pre-hospital delay in the use of intravenous rt-PA for acute ischemic stroke in Japan

In this study we investigated the factors associated with pre-hospital delay to treat acute ischemic stroke and transient attack with intravenous recombinant tissue-plasminogen activator (rt-PA) in Japan. In 625 patients, we investigated the pathways and times of their arrival to our hospital, and the significant and independent factors in the patients' clinical backgrounds associated with delayed arrival (>2 h after notice). In total, 287 patients arrived at our hospital directly via EMS, 113 came by themselves, and 225 transferred from other institutes. Delayed arrivals occurred in 423 patients (68%). Multivariate analyses showed that staying in another hospital at notice, a worsened course, and referral from other institutes were positively related, and evening onset, having a witness at onset, loss of consciousness, and using EMS were negatively related to delayed arrival; a worsened course was positively related, and staying in other hospital at notice, having a witness at onset, loss of consciousness, and a high NIHSS on admission were negatively related to delayed alert; hypercholesterolemia and onset in a nursing home were positively related, and staying in other hospital at notice, loss of consciousness, and a high NIHSS on admission were negatively related to not using EMS. A lack of knowledge concerning stroke emergency by medical staff as well as the general public may be responsible for some stroke patients losing the chance for rt-PA treatment.

Simultaneous treatment with intravenous recombinant tissue plasminogen activator and endovascular therapy for acute ischemic stroke within 3 hours of onset

BACKGROUND AND PURPOSE

Because intravenous (IV) recombinant tissue plasminogen activator (rtPA) does not always lead to a good outcome in a considerable proportion of patients, combined IV rtPA and rescue endovascular therapy (ET) have been performed in several recent studies. However, rescue therapy after completion of IV rtPA often results in late ineffective recanalization. We examined the efficacy and safety of combined IV rtPA and simultaneous ET as primary rather than rescue therapy for hyperacute middle cerebral artery (MCA) occlusion.

MATERIALS AND METHODS

A total of 29 patients eligible for IV rtPA, who were diagnosed as having MCA (M1 or M2) occlusion within 3 hours of onset, underwent thrombolysis. In the combined group, patients were treated by IV rtPA (0.6 mg/kg for 60 minutes) and simultaneous ET (intra-arterial rtPA, mechanical thrombus disruption with microguidewire, and balloon angioplasty) initiated as soon as possible. In the IV group, patients were treated by IV rtPA only.

RESULTS

The improvement of the National Institutes of Health Stroke Scale (NIHSS) score at 24 hours was 11 +/- 4.8 in the combined group versus 5 +/- 4.3 in the IV group (P < .001). In the combined group, successful recanalization was observed in 14 (88%) of 16 patients with no symptomatic intracranial hemorrhage, and 10 (63%) of 16 patients had favorable outcomes (modified Rankin Scale [mRS] 0, 1) at 3 months.

CONCLUSIONS

Aggressive combined therapy with IV rtPA and simultaneous ET markedly improved the clinical outcome of hyperacute MCA occlusion without significant adverse effect. Additional randomized study is needed to confirm our results.

Recanalization between 1 and 24 hours after t-PA therapy is a strong predictor of cerebral hemorrhage in acute ischemic stroke patients

BACKGROUND AND PURPOSE

Intravenous administration of tissue plasminogen activator (t-PA) can improve clinical outcomes in patients with acute ischemic stroke. The most important complication of t-PA therapy is intracerebral hemorrhage (ICH). The aim of this study was to use serial MRI studies to identify independent predictors of symptomatic and asymptomatic ICH after t-PA therapy.

METHODS

Consecutive anterior-circulation ischemic stroke patients treated with t-PA within 3 h of stroke onset were studied prospectively. To identify the presence of recanalization in the occluded arteries and the presence of ICH, MRI, including diffusion weighted imaging (DWI), T2*, and magnetic resonance angiography (MRA), was performed before and 1 h, 24 h, and 5-7 days after t-PA thrombolysis. The independent predictors of ICH were determined using multivariate logistic regression analysis.

RESULTS

41 patients (21 males, 20 females; mean age, 73.2+/-10.7 years) were enrolled, and 19 ICHs (1 symptomatic, 18 asymptomatic) were observed on T2*. The initial MRA demonstrated occluded brain arteries in 31 patients (75.6%), of which follow-up MRA at 1 h, 24 h, and 5-7 days after t-PA therapy revealed recanalization in 48.4%, 80.0%, and 90.0% of patients, respectively. The frequency of recanalization within 1 h after t-PA therapy did not differ between ICH and No-ICH groups, but the ICH group had more frequent recanalization between 1 h and 24 h after t-PA than the No-ICH group (50.0% vs. 4.5%, P=0.001). The ICH group had arterial fibrillation (AF) more frequently than the No-ICH group (78.9% vs. 27.3%, P=0.001). Compared to the No-ICH group, the NIHSS score was higher (16.4+/-5.7 vs. 11.5+/-6.5, P=0.011) and the ASPECTS-DWI value (a normal DWI has an ASPECTS-DWI value of 11 points) was lower (7.3+/-2.4 vs. 8.9+/-1.9, P=0.019) in the ICH group. Multivariate logistic regression analysis demonstrated that the presence of recanalization between 1 and 24 h after the end of t-PA infusion (OR: 20.2; CI: 1.0-340.9; P=0.037) was the only independent predictor of ICH.

CONCLUSION

Recanalization of occluded arteries between 1 and 24 h but not within 1 h after t-PA infusion should be independently associated with symptomatic and asymptomatic ICH after t-PA therapy.

Outline of the Japanese Guidelines for the Management of Stroke 2004 and Subsequent Revision

The “Japanese Guidelines for the Management of Stroke” (chaired by Yukito Shinohara) appeared in 2004, in Japanese, as a result of the collaboration of the Japan Stroke Society, Japanese Society of Neurology, Japan Neurosurgical Society, Japanese Society of Neurological Therapeutics and the Japanese Association of Rehabilitation Medicine. During its preparation, 106 stroke specialists from these societies checked and rated more than 110,000 publications from all over the world, including Japan. We thought it important to develop specific guidelines for Japanese patients, because there are race differences, because some of the approved drugs in Japan are different from those in other counties, and because reports published in Japanese have not been taken into consideration in the development of western guidelines. We also added the Japanese guidelines for use of t-PA in this outline, because there are some differences (e.g., in volume of t-PA) from the guidelines of western countries. Here, we present an outline the Japanese Guidelines for the Management of Stroke 2004 in response to requests, although some updating is already needed. The first revision of the guidelines is expected to be completed in 2008.

Preliminary efficacy report of a novel thrombolytic agent for acute ischaemic stroke within a 5-hour window

BACKGROUND

Adopting thrombolytic therapy with tissue plasminogen activator (tPA) in clinical practice presents many challenges. One major factor is the restrictive time window of 0-3 hours after symptom onset, for the commencement of treatment.

OBJECTIVE

To test the efficacy of a newly developed plasminogen activator (human tissue urokinase type plasminogen activator [HTUPA]) for the treatment of acute ischaemic stroke within 5 hours of symptom onset.

DESIGN

An open-label, dose escalation trial. The initial dose was 0.3 mg/kg and could be increased or decreased depending on tolerability.

SETTING

Three teaching hospitals in Taiwan.

PARTICIPANTS

Thirty-three patients who presented with National Institute of Health Stroke Scale (NIHSS) scores of between 9 and 20, who had evidence of ischaemic stroke confirmed by CT.

MAIN OUTCOMES MEASURES

Efficacy was assessed by the NIHSS, the Modified Rankin Scale (MRS), the Barthel Index and the Glasgow Outcome Scale. Preliminary efficacy endpoints included major neurological improvement at 24 hours and favourable outcome at 90 days after administration of HTUPA.

RESULTS

Of the 33 patients who received HTUPA, 29 received 0.3 mg/kg, 3 received 0.35 mg/kg and 1 received 0.4 mg/kg. Major neurological improvement, defined as improvement of > or =4 points on the NIHSS 24 hours after treatment, was observed in 45% of all patients treated (15/33) and in 48% (14/29) of those treated with 0.3 mg/kg. Ninety days after symptom onset, in those who received HTUPA 0.3 mg/kg, the proportion of patients with a favourable outcome was 34% on the NIHSS (< or =1), 45% on the MRS (0 or 1), 41% on the Barthel Index (> or =95) and 45% on the Glasgow Outcome Scale (1). Eighty six percent of the patients treated with 0.3 mg/kg within 0-3 hours of symptom onset reached scores of 0-1 on both the NIHSS and the MRS.

CONCLUSIONS

Approximately 50% of patients treated with HTUPA 0.3 mg/kg within a 5-hour window after symptom onset experienced major neurological improvement within 24 hours of drug administration. Thrombolytic agents, in this case HTUPA, may be suitable for Taiwanese or Asian patients with acute ischaemic stroke who meet the inclusion criteria.

Randomized Trial of Intraarterial Infusion of Urokinase Within 6 Hours of Middle Cerebral Artery Stroke

Background and Purpose— The Middle Cerebral Artery Embolism Local Fibrinolytic Intervention Trial (MELT) Japan was organized to determine the safety and clinical efficacy of intraarterial infusion of urokinase (UK) in patients with stroke within 6 hours of onset.

Methods— Patients with ischemic stroke presenting within 6 hours of onset and displaying occlusions of the M1 or M2 portion of the middle cerebral artery on carotid angiography were randomized to the UK or control groups. Clinical outcome was assessed by the modified Rankin Scale, National Institutes of Health Stroke Scale, and Barthel Index.

Results— The Independent Monitoring Committee recommended stopping the trial after approval of intravenous infusion of recombinant tissue plasminogen activator in Japan. A total of 114 patients underwent randomization, 57 patients in each group. Background characteristics were comparable between the 2 groups. The primary end point of favorable outcome (modified Rankin Scale 0 to 2) at 90 days was somewhat more frequent in the UK group than in the control group (49.1% and 38.6%, OR: 1.54, 95% CI: 0.73 to 3.23) but did not reach a significant level ( P =0.345). However, excellent functional outcome (modified Rankin Scale 0 to 1) at 90 days, a preplanned secondary end point, was more frequent in the UK group than in the control group (42.1% and 22.8%, P =0.045, OR: 2.46, 95% CI: 1.09 to 5.54). There were significantly more patients with National Institutes of Health Stroke Scale 0 or 1 at 90 days in the UK group than the control group ( P =0.017). The 90-day cumulative mortality was 5.3% in the UK group and 3.5% in the control group ( P =1.000), and intracerebral hemorrhage within 24 hours of treatment occurred in 9% and 2%, respectively ( P =0.206).

Conclusions— The trial was aborted prematurely and the primary end point did not reach statistical significance. Nevertheless, the secondary analyses suggested that intraarterial fibrinolysis has the potential to increase the likelihood of excellent functional outcome.

Post-licensed 1-year experience of systemic thrombolysis with tissue plasminogen activator for ischemic stroke in a Japanese neuro-unit

OBJECTIVE

In Japan, intravenous thrombolysis with tissue plasminogen activator (tPA) for ischemic stroke within 3h of onset was officially approved in October 2005.

METHODS

We report initial 1-year clinical experience of intravenous alteplase at 0.6mg/kg in a Japanese neuro-unit.

RESULTS

Twenty patients received intravenous tPA, corresponding to 12% of all ischemic strokes (n=166) and 38% of ischemic strokes within 3h of onset (n=52). The mean age was 68 years old and 15% had pre-morbid dependency with modified Rankin Scale (mRS) of 3 or 4. The median baseline National Institute of Health Stroke Scale score was 19 points (range; 5-37). Average time from stroke onset to tPA delivery was 136 min (range; 87-180). Of 18 (90%) patients receiving pretreatment vascular imaging, 16 (80%) patients had a large arterial occlusion. At 3 months, excellent outcome with mRS of 0 or 1 was 25%, and good outcome with mRS of 0-2 was 35%. One patient (5%) developed symptomatic intracranial hemorrhage within 36 h. Mortality rate was 15%.

CONCLUSIONS

Intravenous tPA within 3h was safe and feasible, and possibly effective in clinical practice. The higher stroke severity in our cohort precluded to compare the sufficient effectiveness with clinical trials. In Japan, a post-licensed national surveillance is currently under way.

Neurotoxic effects of exogenous recombinant tissue-type plasminogen activator on the normal rat brain

Thrombolytic therapy with intravenous and intra-arterial recombinant tissue-type plasminogen activator (rtPA) has been established for the treatment of acute ischemic stroke. However, tPA has also been suggested to have neurotoxic effects. The purpose of this study was to examine direct neurotoxicity of rtPA in vivo. The animals (Wistar rats) were divided to the following three groups: low-dose (15 micromol/L) rtPA group (n = 6); high-dose (30 micromol/L) rtPA group (n = 6); and control (physiological saline) group (n = 6). The rtPA solution was perfused into the cortex via a microdialysis probe. The volume of the lesion was quantified histologically by image analysis of the lesions. Blood-brain barrier (BBB) disruption was evaluated by intravenous injection of Evans blue, and injury to the basal lamina was evaluated by immunohistochemistry using an anti-laminin antibody. In the rtPA-perfused animals, a pale lesion was produced around the probe, and microscopically, neurons showed necrotic changes. The volume of the lesions increased significantly as the concentration of perfused rtPA was increased. Marked extravasation of Evans blue was observed, and laminin immunoreactivity of blood vessels in the rtPA-induced lesions was lost. These results suggest that rtPA promotes acute direct neurotoxicity and participates in disruption of the microvascular basal lamina to cause BBB disruption, thereby increasing edema formation.