Intracarotid urokinase with thromboembolic occlusion of the middle cerebral artery

Clinical and radiological outcomes of acute ischemic stroke patients without angiographic occlusion on digital subtraction angiogram. A pooled analysis of case series

INTRODUCTION

Approximately 20-30% of the patients with acute ischemic stroke do not have any occlusion demonstrated on initial digital subtraction angiography (DSA). We sought to determine the risk and rates of cerebral infarction and favorable neurological outcome in this group of acute ischemic stroke patients.

MATERIALS AND METHODS

Patients were identified from a prospectively maintained stroke database and from literature search of MEDLINE, PubMed, and Cochrane databases. All patients had initial neurological assessment on National Institutes of Health Stroke Scale (NIHSS). Patients then underwent DSA after initial head computed tomography (CT) scans. Follow-up radiological assessment at 24-72 h was performed with CT and magnetic resonance imaging scans. Association of stroke risk factors with clinical and radiological outcomes was estimated.

RESULTS

A total of 81 patients was analyzed (mean age 63 years; 28 were women). The median NIHSS score was 8 (range 2-25). None of the patients received either intravenous or intra-arterial thrombolytic. Cerebral infarction was detected in 62 (76%) of the 81 patients. Twenty-four to 48-h NIHSS was available for 51 patients only. Neurological improvement was observed in 22 (43%) of the 51 patients. Favorable outcome ascertained at 3-month follow-up was seen in 48 (59%) of the 81 patients. After adjusting for age, sex, and baseline NIHSS, male patients [odds ratio (OR) 4.5 (1.4-14.3), p value = 0.01] and patients with age >or=65 [OR 4.3 (1.2-16.2), p value = 0.03] have a higher risk of cerebral infarcts on the follow-up imaging. Similarly, patients who presented with <10 NIHSS had a better 3-month outcome than those with >10 NIHSS [OR 0.21 (0.08-0.61), p value = 0.004].

CONCLUSION

Ischemic stroke patients without arterial occlusion on DSA have a higher risk of cerebral infarction and disability particularly in men, patients over 65 years of age and with NIHSS >or=10. The cause of infarction may have been arterial obstruction with spontaneous recanalization or small vessel occlusion not visible on DSA.

Vertebrobasilar recanalization after 12 h of onset using balloon expandable stent and thrombolysis

Basilar artery (BA) thrombosis is a severe condition that has a high percentage of mortality if no treatment is performed. Recanalization is the most successful way of reducing mortality and improving outcome in patients with BA thrombosis. We present a case of a patient that presented to our hospital 12 h after onset of symptoms in which a combination of techniques were used to perform a vertebrobasilar recanalization.

Anterior cerebral artery emboli in combined intravenous and intra-arterial rtPA treatment of acute ischemic stroke in the IMS I and II trials

BACKGROUND AND PURPOSE

Anterior cerebral artery (ACA) emboli may occur before or during fibrinolytic revascularization of middle cerebral artery (MCA) and internal carotid artery (ICA) T occlusions. We sought to determine the incidence and effect of baseline and new embolic ACA occlusions in the Interventional Management of Stroke (IMS) studies.

MATERIALS AND METHODS

Case report forms, pretreatment and posttreatment arteriograms, and CTs from 142 subjects entered into IMS I & II were reviewed to identify subjects with baseline ACA occlusion, new ACA emboli occurring during fibrinolysis, subsequent CT-demonstrated infarction in the ACA distribution, and to evaluate global and lower extremity motor clinical outcome.

RESULTS

During M1/M2 thrombolysis procedures, new ACA embolus occurred in 1 of 60 (1.7%) subjects. Baseline distal emboli were identified in 3 of 20 (15%) T occlusions before intra-arterial (IA) treatment, and new posttreatment distal ACA emboli were identified in 3 subjects. At 24 hours, 8 (32%) T occlusions demonstrated CT-ACA infarct, typically of small volume. Infarcts were less common following sonography microcatheter-assisted thrombolysis compared with standard microcatheter thrombolysis (P = .05). Lower extremity weakness was present in 9 of 10 subjects with ACA embolus/infarct at 24 hours. The modified Rankin 0 to 2 outcomes were achieved in 4 of 25 (16%) subjects with T occlusion overall, but in 0 of 10 subjects with distal ACA emboli or ACA CT infarcts (P = .07).

CONCLUSIONS

With IV/IA recombinant tissue plasminogen activator treatment for MCA emboli, new ACA emboli are uncommon events. Distal ACA emboli during T-occlusion thrombolysis are not uncommon, typically lead to small ACA-distribution infarcts, and may limit neurologic recovery.

[Thrombolysis for ischemic stroke: an update]

Even 10 years after the approval of thrombolysis this life-saving and disability reducing therapy is still underused. Important reasons for that are very strict inclusion criteria such as the early and narrow time-window, fear of bleeding complications and doubts regarding the effectiveness. An intensive and constant effort is required to educate the public that stroke is a treatable emergency. In addition to the medical reasons, economic considerations in a context of decreasing resources emphasize the importance of effective stroke treatment. The results of numerous recent studies such as the European register SITS-MOST help to strengthen the confidence in thrombolysis. In addition the development and advancement of new imaging tools such as multiparametric MRI and advanced CT-techniques will improve patient selection and may enable us to extend the time-window for treatment. Intraarterial thrombolysis, "bridging" methods and new devices for intravascular intervention are the subjects of intensive ongoing research. Even though no randomized trials are available intraarterial thrombolysis is the treatment of choice for acute basilar occlusion, but if this intervention is not available an intravenous approach may be an equal alternative.

Review of the Current Status of Intra-Arterial Thrombolysis for Treating Acute Cerebral Infarction: a Retrospective Analysis of the Data from Multiple Centers in Korea

Objective

The purpose of the study was to review the current status of intra-arterial (IA) thrombolysis in Korea by conducting a retrospective analysis of the data from multiple domestic centers.

Materials and Methods

The radiologists at each participating institution were asked to fill out case report forms on all patients who had undergone IA recanalization due to acute anterior circulation ischemia. These forms included clinical, imaging and procedure-related information. A central reader analyzed the CT/MR and angiographic results. The rates of successful recanalization, hemorrhagic transformation and functional outcome were obtained. The univariate analyses were performed together with the multivariate analysis.

Results

We analyzed the data from 163 patients, and they had been treated at seven institutes. The initial imaging modalities were CT for 46 patients (28%), MR for 63 (39%), and both for 54 (33%). Various mechanical treatment methods were applied together in 50% of the patients. Radiologically significant hemorrhage was noted in 20/155 patients (13%). We found various factors that influenced the recanalization rate and the occurrence of significant hemorrhagic transformations. The favorable outcome rate, reported as modified Rankin Scale ≤ 2, was 40%, and the mortality rate was 11%. The factors that predicted a poor functional outcome were old age (p = 0.01), initially severe neurological symptoms (p < 0.0001), MR findings of a wide distribution of lesions (p = 0.001), involvement of the basal ganglia (p = 0.01), performance of procedures after working hours (p = 0.01), failure of recanalization (p = 0.003), contrast extravasation after the procedure (p = 0.007) and significant hemorrhagic transformation (p = 0.002). The subsequent multivariate analysis failed to show any statistically significant variable.

Conclusion

There was a trend toward increased dependency on MR imaging during the initial evaluation and increased usage of combined pharmacologic/mechanical thrombolysis. The imaging and clinical outcome results of this study were comparable to those of the previous major thrombolytic trials.

Hyperacute therapy of acute ischemic stroke: intraarterial thrombolysis and mechanical revascularization strategies

Ischemic stroke is a major cause of morbidity and mortality. Despite the fact that it is the third most common cause of death in the United States, there is only one FDA approved treatment for patients. This is Intravenous recombinant tissue plasminogen activator given within 3 hours of symptom onset. Furthermore, despite the approval of this drug, it has been underutilized in the community. The limited time window of 3 hours disqualifies many patients from receiving the drug. In addition, fears of intracranial hemorrhage have resulted in underutilization of the drug in the community setting. Efforts to increase the time window to treatment include utilization of the intraarterial route for delivery of thrombolytic drug and interventional mechanical strategies to revascularize intracranial vessels. In this report we review the major intraarterial thrombolysis trials and review the mechanical strategies being developed to treat patients with acute ischemic stroke.

Recent Advances in the Interventional Treatment of Acute Ischemic Stroke

BACKGROUND

Acute ischemic stroke is a major cause of morbidity and mortality in Europe, North America, and Asia. Recent advances over the past decade have been made in the interventional approach to patients with a stroke. These include intravenous (i.v.) trials, intra-arterial (i.a.) trials, combined i.v./i.a. trials, and newer devices undergoing current clinical evaluation to mechanically remove clot within the cerebral circulation.

METHODS

A summary of the latest interventional approaches to stroke, from the interventional neuroradiology perspective, is presented. Results of the major thrombolytic trials over the past decade are summarized. Newer devices and approaches for ischemic stroke patients, including the recently completed Phase 1/2 MERCI (Mechanical Embolus Removal in Cerebral Ischemia) Trial are presented.

RESULTS

The Proact 1 and 2 trials involving i.a. thrombolytic therapy in patients who present with an acute middle cerebral artery stroke within 6 h from symptom onset have demonstrated significant benefit over the control group, for improved outcomes at 90 days. The MERCI trial has demonstrated, in 114 patients with moderate to severe strokes, that patients who are able to be recanalized have significant neurological improvement versus those who were not able to be recanalized.

CONCLUSIONS

Continued advances in the interventional approach to acute stroke treatment, with further clinical trials, are warranted. Early reports are encouraging regarding both combination thrombolytic drug trials and mechanical device trials for these patients.

Recanalisation of middle cerebral artery occlusion after intra-arterial thrombolysis: different recanalisation grading systems and clinical functional outcome

BACKGROUND

Different grading systems of arterial recanalisation have never been compared in large series of stroke patients treated with intra-arterial thrombolysis (IAT).

METHODS

Clinical and angiographic findings and outcome were analysed in 147 patients with M1 or M2 segment occlusion of the middle cerebral artery treated with IAT. Associations of the thrombolysis in myocardial infarction (TIMI) grading system and the Mori grading system with clinical outcome were compared.

RESULTS

The median NIHSS score on admission was 15 and the mean time from symptom onset to IAT was 242 minutes. After three months the outcome was favourable (defined as modified Rankin scale score (mRS) < or = 2) in 85 patients (58%) and poor (mRS 3 to 5) in 44 (30%); 18 patients (12%) were dead. Recanalisation was categorised as TIMI grade 0 in 17 patients (12%), TIMI 1 in 16 (11%), TIMI 2 in 83 (56%), and TIMI 3 in 31(21%). Seventeen patients (12%) showed Mori grade 0 reperfusion, 16 (11%) Mori 1, 37 (25%) Mori 2, 46 (31%) Mori 3, and 31 (21%) Mori 4. In both TIMI and Mori grading systems, reopening the artery was an independent predictor of a favourable clinical outcome (p < 0.0001). When recanalisation was partial, outcome was better in patients with reperfusion >50% (Mori 3) than in those with reperfusion <50% (Mori 2) (p = 0.008).

CONCLUSIONS

Both TIMI and Mori grading systems are useful for predicting outcome after stroke and IAT. When recanalisation is partial the Mori classification is more refined in giving prognostic information.

A Case-Control Analysis of Intra-Arterial Urokinase Thrombolysis in Acute Cardioembolic Stroke

BACKGROUND

Intra-arterial urokinase (IA-UK) thrombolysis is frequently given in Japan to selected patients with acute cerebral artery occlusion. However, it is not clear whether or not IA-UK thrombolysis has an efficacy for acute stroke patients. The purpose of this study was to assess the effects of IA-UK thrombolysis in acute cardioembolic stroke patients, by performing a case-control analysis using data from Japan's Multicenter Stroke Investigator's Collaboration (J-MUSIC).

METHODS

16,922 acute ischemic stroke patients were enrolled into J-MUSIC. From these patients, we selected 91 patients (UK group) who met the following criteria: treatment with IA-UK; 20-75 years of age; cardioembolic stroke; presenting with a carotid stroke; admission within 4.5 h of symptom onset, and a National Institutes of Health Stroke Scale (NIHSS) score of 5-22 points on admission. A control group of 182 patients without IA-UK treatment and matched to the NIHSS score, gender, and age was chosen. We compared the modified Rankin scale (mRS) score at discharge and the mortality between the 2 groups.

RESULTS

In both groups, the mean age was 65 +/- 8 years, and the median NIHSS score was 14. The mean interval between symptom onset and UK administration was 3.4 +/- 1.3 h, and the IA-UK dose was 392,000 +/- 200,000 units. The mRS score at discharge was lower in the UK group than in the control group (mean, SD, median; 2.8, 2.9, 2 in UK group vs. 3.3, 1.8, 4, in the control, respectively p = 0.031). A favorable outcome (mRS of 0-2) was more frequently observed in the UK group (50.5%) than in the control group (34.1%, p = 0.0124). No difference in the mortality rate was seen between the UK group (11.0%) and the control group (13.3%). As well, there was no difference in the length of hospital stay between the UK group (46 +/- 41 days, mean +/- SD) and the control group (42 +/- 42 days, mean +/- SD).

CONCLUSIONS

IA-UK thrombolytic therapy may improve the outcome in hyperacute cardioembolic stroke patients.

Comparison of intravenous and intra-arterial urokinase thrombolysis for acute ischaemic stroke

Intravenous fibrinolysis (IVF) with rt-PA (alteplase) provides significant benefits in acute ischaemic stroke when it is given within the first three hours following stroke onset. Intra-arterial fibrinolysis (IAF) with pro-urokinase in PROACT II study provides quite the same benefit in the first 6 hours. IVF and IAF have never been compared. To compare the efficacy and safety of IVF and IAF with urokinase given within the first 6 hours of acute ischaemic stroke. Patients fulfilling the selection criteria were randomly assigned to receive urokinase 900,000 units via intravenous or intra-arterial routes. This randomised monocentre study was done between December 1995 and August 1997. The primary outcome was defined as the number of patients with a modified Rankin score of 2 or less. Secondary outcomes included mortality, frequency of symptomatic intracranial haemorrhage (SIH), neurological and functional scores. Fourteen patients were given IVF and 13 IAF. The study was terminated by the National Health Authorities when 27 patients had been included because of the mortality rate. Seven patients (26%) died, 4 in the IV group (oedematous infarct in 3 and recurrence in 1), 3 in the IA group (SIH in 2, and oedematous infarct in 1). Patients given IVF were treated significantly earlier (4:16 h vs 5:24 h; p=.007). Although IA patients showed greater and earlier improvement there was no significant difference in primary and secondary outcomes. Because of premature termination, the trial was too small to provide any reliable and conclusive results. Intra-arterial fibrinolysis began significantly later than IV fibrinolysis but it gave non-significantly better results in this prematurely terminated study.

Intraarterial thrombolysis for thromboemboli associated with endovascular aneurysm coiling. Report of five cases

SUMMARY

With the rapidly developing applications of GDC endovascular aneurysm embolization, the recognition and treatment of potential intra-procedural complications is crucial to reducing the morbidity and mortality of this procedure. Thromboembolic complications occur with an incidence of 2-11% with endovascular aneurysm coiling. We describe five cases in which the intraarterial use of thrombolytics was applied to disrupt a fresh clot and recanalize the occluded vessels with variable angiographic and clinical success. Five cases are presented in which thromboembolic complications occurred during or shortly after GDC endovascular aneurysm occlusion. The complication was recognized while depositing coils in two cases, on post-embolization angiogram in one, and a few hours following embolization in two cases in which a new neurologic deficit developed in the ICU. In those cases recognized while the microcatheter was near the aneurysm site, immediate thrombolysis was performed at the site of occlusion. The patients who developed a new neurologic deficit were returned to the endovascular suite and the site of occlusion was noted to be distal to the coiled aneurysm. Clot disruption was performed with the microcatheter before delivering intraarterial thrombolytics. Thromboembolic complications of GDC aneurysm embolization are fortunately rare and can be managed with delivery of thrombolytic therapy at the site of occlusion. Intraarterial thrombolysis of fresh clot caused by GDC aneurysm occlusion can successfully open the occluded vessels but not without serious risk of hemorrhage.

Intraarterial Thrombolytic Therapy within 3 Hours of the Onset of Stroke

OBJECTIVE

The National Institute of Neurological Disorders and Stroke (NINDS) Recombinant Tissue Plasminogen Activator Stroke Study Group showed that recombinant tissue plasminogen activator (rt-PA) administered intravenously within 3 hours of the onset of ischemic stroke can improve clinical outcome. Intraarterial (IA) thrombolysis has been shown to offer advantages over intravenous (IV) thrombolysis, but experience with this type of therapy within 3 hours of the onset of symptoms has not been reported previously. This study is the first retrospective analysis of a two-institution experience with IA thrombolysis within 3 hours of stroke onset.

METHODS

A total of 36 patients with angiographically demonstrated occlusions were treated with urokinase or rt-PA within 3 hours of stroke onset. Outcome measures included the percentage of patients with no or minimal neurological disability at 30 to 90 days as measured by the modified Rankin Scale, percentage recanalization, incidence of symptomatic intracranial hemorrhage, and mortality rate. The results were compared with those of the NINDS rt-PA study.

RESULTS

The median admission National Institutes of Health Stroke Scale score was 14. Fifty percent of treated patients had a modified Rankin Scale score of 0 or 1 indicating no or little disability at 1 to 3 months compared with 39% of treated patients in the NINDS trial. Recanalization was 75%, symptomatic intracranial hemorrhage was 11% (versus 6.4% with IV rt-PA in the NINDS trial), and the mortality rate was 22% (versus 17% with IV rt-PA in the NINDS trial).

CONCLUSION

The results suggest that IA thrombolysis administered within 3 hours of stroke onset is a feasible and viable alternative to IV rt-PA on the basis of improved clinical outcomes, high recanalization percentage, and comparable mortality rate and despite increased symptomatic intracranial hemorrhage. Whether IA thrombolysis is superior to IV therapy awaits further study.

Intraarterial Thrombolysis Trials in Acute Ischemic Stroke

Stroke is a common cause of death and disability in industrialized nations. Technical advances and the increased availability of noninvasive brain imaging techniques have permitted precise and early diagnosis of acute cerebral ischemia. This has made emergent thrombolytic therapy for rapid restoration of cerebral perfusion increasingly possible. Herein, the authors present a review of the clinical trials investigating acute stroke treatment with intraarterial thrombolysis.

Assessment of the patient with hyperacute stroke: imaging and therapy

Neuroimaging is an important part of the assessment of patients with hyperacute stroke. As new treatments that may reverse cerebral ischemia have been developed, the role of neuroimaging has changed from simply anatomic depiction of early infarction to identification, by means of physiologic (rather than simply anatomic) information, of regions that are at risk for infarction. The goal of such imaging techniques is to monitor successes and complications of recently developed treatments such as thrombolysis.

Intraarterial Thrombolysis with r-tPA for Treatment of Anterior Circulation Acute Ischemic Stroke. Technical and Clinical Results

SUMMARY

To investigate factors effecting the safety and recanalization efficacy of local intraarterial (IA) recombinant tissue plasminogen activator (r-tPA) delivery in patients with acute ischemic stroke. Eleven patients with anterior circulation acute ischemic stroke were treated. The neurological status of the patients were graded with the Glasgow Coma Scale (GCS) and National Institute of Health Stroke Scale (NIHSS). All patients underwent a computed tomography (CT) examination at admission. In addition four patients had diffusion-weighted and one patient had a perfusion magnetic resonance (MR) examinations. Patients were treated within six hours from stroke onset. Immediate, six hours, and 24 hours follow-up CT examinations were performed in order to evaluate the haemorrhagic complications and the extent of the ischemic area. The Rankin Scale (RS) was used as an outcome measure. Two of the 11 patients had carotid "T" occlusion (CTO), nine had middle cerebral artery (MCA) main trunk occlusion. Four patients had symptomatic haemorrhage with a large haematoma rupturing into the ventricles and subarachnoid space. Of these, three patients died within 24 hours. The remaining seven patients had asymptomatic haematomas that were smaller compared to symptomatic ones, and showed regression in size and density on follow-up CTs. At third month five patients had a good outcome and three patients had a poor outcome. In acute ischemic stroke, local IA thrombolysis is a feasible treatment when you select the right patient. Haemorrhage rate does not seem to exceed that occuring in the natural history of the disease and in other treatment modalities.

Models of focal cerebral ischemia in the nonhuman primate

Ischemic stroke is a uniquely human disease syndrome. Models of focal cerebral ischemia developed in nonhuman primates provide clinically relevant platforms for investigating pathophysiological alterations associated with ischemic brain injury, microvascular responses, treatment responses, and clinically relevant outcomes that may be appropriate for ischemic stroke patients. A considerable number of advantages attend the use of nonhuman primate models in cerebral vascular research. Appropriate development of such models requires neurosurgical expertise to produce single or multiple vascular occlusions. A number of experimentally and clinically accessible outcomes can be measured, including neurological deficits, neuron injury, evidence of non-neuronal cell injury, infarction volume, real-time imaging of injury development, vascular responses, regional cerebral blood flow, microvascular events, the relation between neuron and vascular events, and behavioral outcomes. Nonhuman primate models of focal cerebral ischemia provide excellent opportunities for understanding the vascular and cellular pathophysiology of cerebral ischemic injury, which resembles human ischemic stroke, and the appropriate study of pharmacological interventions in a human relevant setting.

Clinical potential of intra-arterial thrombolytic therapy in patients with acute ischaemic stroke

Acute ischaemic stroke is a leading cause of mortality and morbidity around the world. An arterial occlusive lesion is found in the majority of patients with acute ischaemic stroke, and recanalisation has been shown to result in a better clinical outcome. The only widely approved recanalisation strategy is the use of intravenous alteplase (recombinant tissue-type plasminogen activator; tPA) within 3 hours of stroke onset. However, this therapy has limitations, and alternative or supplemental recanalisation strategies need to be considered in a large number of patients with acute ischaemic stroke. One such promising strategy is intra-arterial thrombolysis. This article reviews the pharmacology of the various drugs used for intra-arterial thrombolysis in the setting of acute ischaemic stroke and the results of the clinical trials that have studied their benefit. Three generations of thrombolytic agents have been available for clinical use so far. The first-generation agents such as streptokinase and urokinase were the first to be studied in acute stroke, and a number of positive case reports and series of their intra-arterial use have been reported from around the world. Second-generation products include alteplase and pro-urokinase. The clinical benefits of intra-arterial pro-urokinase were recently proven in a randomised, placebo-controlled study. Third-generation agents, such as reteplase, lanoteplase and tenecteplase, offer superior recanalisation rates with limited systemic adverse effects and might prove to be the agents of choice for intra-arterial acute stroke thrombolysis in the future. The exact administration regimens as well as the identification of patient sub-populations most likely to benefit from intra-arterial thrombolysis are subjects of current investigations, and hopefully firmer guidelines will be established in the next few years, once the results of the clinical trials are available.

Developments in endovascular therapy for acute ischemic stroke

Treatment for acute ischemic stroke has for years been frustrated by lack of efficacy. Despite a plethora of seemingly promising treatments from animal research, clinical application never came to fruition. Experience seems to indicate that the only truly effective treatment is the rapid restoration of perfusion to ischemic tissue prior to frank infarction. Unfortunately, every agent designed to achieve this goal met with the same ironic limitation; the ability to dissolve clot was coupled with the risk of causing intracerebral hemorrhage. Accordingly, stroke was addressed primarily through modification of risk factors and rehabilitation of the neurological sequelae. However, following the randomized trial of intravenous tissue-type plasminogen activator (t-PA) sponsored by the National Institutes of Neurological Disorders and Stroke (NINDS) in 1995, the first proven effective therapy for acute stroke became available. The door was finally open to emergency treatment of stroke in the acute phase. Moreover, the positive results of the NINDS trial appear to be independent of age. Nevertheless, intravenous thrombolysis remains ineffective in the majority of patients treated and is withheld from an even larger population because of presentation outside of the 3-hour therapeutic window. As a result, effective therapy is not available for most patients presenting with acute stroke. Recent advancements in the evaluation and treatment of acute ischemic stroke, including intra-arterial thrombolysis, mechanical thrombolysis, and combination therapies, hold significant promise for a larger proportion of patients. New imaging technology may also improve our ability to identify patients with viable brain tissue who may derive the greatest benefit from these therapies.

Local intraarterial urokinase thrombolysis of acute ischemic stroke with or without intravenous abciximab: a pilot study

PURPOSE

One of the most important prognostic factors in the thrombolytic treatment of acute ischemic stroke is the time to recanalization. To shorten the recanalization time, an antiplatelet agent, abciximab (platelet glycoprotein receptor IIb/IIIa antagonist), was administered intravenously before the initiation of local intraarterial urokinase thrombolysis. The purpose of this study was to evaluate the effectiveness and safety of this combined therapy.

MATERIALS AND METHODS

A total of 26 patients with acute ischemic stroke (National Institutes of Health Stroke Scale score >10) were enrolled in this study. In the earlier phase of this study, conventional local intraarterial urokinase thrombolysis was performed in 16 patients (urokinase group). In the later phase, combined use of intravenous abciximab and local intraarterial urokinase thrombolysis was performed in 10 patients (urokinase + abciximab group). Recanalization rate (Thrombolysis in Myocardial Infarction grade >or=2), total amount of urokinase used, incidence of symptomatic hemorrhage, and better functional outcome rate (modified Rankin scale <or=2) were compared between the two groups with use of the Fisher exact test or Mann-Whitney U test.

RESULTS

The recanalization rate in the urokinase + abciximab group (90%, nine of 10) was significantly higher than that in the urokinase group (43.8%, seven of 16) (P =.037). The mean amount of urokinase required for recanalization was significantly lower in the urokinase + abciximab group (828,000 IU vs 418,000 IU; P <.005). As for the incidence of symptomatic hemorrhage, no significant difference was noted between the two groups (four of 16 vs three of 10) (P = 1.0). The urokinase + abciximab group showed a trend of better functional outcome (50% vs 80%; P =.2).

CONCLUSIONS

Combined therapy employing intravenous abciximab and local intraarterial urokinase thrombolysis showed a marked improvement in recanalization rate and showed a trend of better functional outcome. The safety of this regimen still remains to be justified with modification of the indication and regimen dosage.

New grading system for angiographic evaluation of arterial occlusions and recanalization response to intra-arterial thrombolysis in acute ischemic stroke

OBJECTIVE

The Thrombolysis in Myocardial Infarction (TIMI) grading scheme and other classification systems are limited because they do not account for occlusion location or collateral circulation. A new scheme for angiographic classification of arterial occlusion and recanalization response to intra-arterial thrombolysis in acute ischemic stroke was designed because of limitations in existing grading systems.

METHODS

The proposed scheme assigns a score from 0 to 5 on the basis of occlusion site and collateral supply. The pre- and post-thrombolysis angiograms of 15 patients with acute ischemic stroke were independently graded by three neurointerventionists according to TIMI perfusion grade (0-3), a grading scheme developed by Mori et al. (Mori E, Tabuchi M, Yoshida T, Yamadori A: Intracarotid urokinase with thromboembolic occlusion of the middle cerebral artery. Stroke 19:802-812, 1988) (0-4), and the proposed scheme (0-5); and interobserver agreement was assessed. The effect of severity of initial arterial occlusion on outcomes of good recovery (National Institutes of Health Stroke Scale score of < or =4) or death at 7 days after thrombolysis according to the proposed and TIMI grading schemes was also assessed in 60 patients with acute ischemic stroke. Multivariate analyses were performed to assess these relationships after adjusting for patient age, sex, time interval between symptom onset and treatment, and thrombolytic agent used.

RESULTS

Interobserver agreement was higher for pre- and posttreatment grading of angiographic images using the new classification scheme (kappa = 0.73) than with either TIMI perfusion grade (kappa = 0.68) or Mori et al. grade (kappa = 0.68). The proposed grading scheme was inversely associated with good recovery at 7 days (odds ratio, 0.4; 95% confidence interval, 0.2-0.9) and directly associated with 7-day mortality (odds ratio, 2.0; 95% confidence interval, 1.1-3.6) after treatment. Initial TIMI grade did not correlate with either good recovery or death at 7 days. An inverse trend was observed between initial severity of angiographic occlusion as determined by the proposed scheme and complete recanalization after treatment (odds ratio, 0.6; 95% confidence interval, 0.4-1.02).

CONCLUSION

Application of the new classification scheme for assessing pretreatment occlusion and response to intra-arterial thrombolysis resulted in high interobserver agreement and correlated with 7-day outcomes. The six grades used in this scheme allowed precise angiographic evaluation of perfusion changes.

Combined central retinal arterial and venous obstruction: emergency ophthalmic arterial fibrinolysis

PURPOSE

To investigate the role of urokinase selectively perfused into the ophthalmic artery as an emergency treatment for combined central retinal arterial obstruction (CRAO) and central retinal venous obstruction (CRVO).

MATERIALS AND METHODS

Over a 6-year period, 11 consecutive patients presented with recent combined CRAO and CRVO (< or =72 hours). Urokinase (300,000 IU) was selectively perfused via the femoral artery into the ophthalmic artery for 40 minutes. Evaluation criteria were Snellen visual acuity with best correction, funduscopic results, and retinal arteriovenous transit time assessed over a mean 3.5-year follow-up. Mean vision and retinal perfusion were tested by means of repeated-measures analysis of variance. The correlation between visual improvement and retinal perfusion improvement was evaluated by means of Spearman rank correlation.

RESULTS

Substantial improvement in vision and retinal perfusion was noted in seven of the 11 patients treated. Mean vision improvement was significant (P =.009) within 24-48 hours after fibrinolysis, increased until 1 month after (P =.006), then remained stable throughout the follow-up (P >.10). Visual improvement correlated with retinal perfusion improvement during the period from before fibrinolysis to 24-48 hours after (P =.028). In all patients with improved results, retinal hemorrhages transiently increased. One patient had intravitreal hemorrhage shortly after fibrinolysis.

CONCLUSION

For this uncommon clinical entity, which typically has a poor visual outcome, these results suggest that ophthalmic arterial fibrinolysis may restore retinal perfusion, which leads to rapid substantial visual improvement in many cases of combined CRAO and CRVO, without systemic complications, but it may be responsible for intravitreal hemorrhage.

Endovascular administration after intravenous infusion of thrombolytic agents for the treatment of patients with acute ischemic strokes

OBJECTIVE

To determine the feasibility of combined intravenous and intra-arterial thrombolytic therapy for acute ischemic strokes and to evaluate its associated risks, using magnetic resonance imaging as a triage tool. Intravenous treatment followed by intra-arterial infusion may increase the rate of recanalization and lead to better clinical results, with reduced frequency of intracranial hemorrhage.

METHODS

Our Brain Attack Team evaluated patients who presented within 3 hours after symptom onset. Patients who did not demonstrate improvement and exhibited no evidence of intracranial hemorrhage on head computed tomographic scans were treated with intravenously administered recombinant tissue plasminogen activator (0.6 mg/kg) and underwent emergency magnetic resonance imaging of the head. T2-weighted turbo-gradient and spin echo and echo-planar diffusion- and perfusion-weighted imaging scans were obtained. Patients with evidence of imaging abnormalities indicating acute cortical infarction underwent cerebral angiography. After determination of vessel occlusion, intra-arterially administered urokinase (up to 750,000 units) or intra-arterially administered recombinant tissue plasminogen activator (maximal dose, 0.3 mg/kg) was used to achieve recanalization.

RESULTS

We treated 45 patients with this protocol. The mean age was 67 +/- 13 years, and 58% of the patients were women. There was a significant improvement in National Institutes of Health Stroke Scale scores after treatment. There was good correlation between abnormal perfusion-weighted imaging findings and cerebral angiographic findings (complete vessel occlusion). The incidence of symptomatic intracranial hemorrhage was 4.4% in this cohort. Seven patients died in the hospital, and the majority of survivors (77%) experienced good outcomes (Barthel index of >or=95) 3 months after treatment.

CONCLUSION

Our data demonstrate that this protocol is feasible and that combined intravenous and intra-arterial thrombolysis to treat acute ischemic strokes is sufficiently safe to warrant further evaluation.

Referral and care for acute ischemic stroke in a Japanese tertiary emergency hospital

To examine the current emergency referral and care for acute stroke at a Japanese tertiary emergency hospital with a 24-h stroke team and care unit, we surveyed the presentations of patients with acute ischemic stroke or transient ischemic attack (TIA) seen within 7 days of onset. Delay from symptom onset to arrival at our hospital, from arrival to initial diagnostic brain computed tomography (CT), and the type of anti-thrombotic treatments were evaluated. During the 18-month period, there were 254 ischemic events in 244 patients; 239 (94%) had an ischemic stroke and 15 (6%) TIA. Eighty-two (32%) events presented within 3 h of onset, and 102 (40%) and 179 (70%) within the first 6 and 24 h, respectively. The median delay from hospital arrival to CT was 32 min, ranging 10 min to 22 h. Two hundred (79%) events underwent CT within 1 h of arrival (n=172) or at the referral hospitals before transfer (n=28). Direct ambulance transportation and more severe neurological deficits were independent predictors both for early arrival and short in-hospital delay to CT. Anti-thrombotic therapies including anticoagulant and/or antiplatelet medications were given in 237 (93%) episodes. Two (1%) patients received thrombolysis, although 18 (7%) patients fulfilled the National Institute of Neurological Disorders and Stroke guidelines for intravenous thrombolysis with tissue plasminogen activator. As in western communities, our pre-hospital emergency referral systems for acute stroke require substantial improvements including the wider use of ambulance calling. Although our in-hospital stroke management is functioning relatively well, further efforts are necessary in reducing the diagnostic delay.

Thrombolytic therapy for ischemic stroke--a review. Part II--Intra-arterial thrombolysis, vertebrobasilar stroke, phase IV trials, and stroke imaging

OBJECTIVE

Intra-arterial thrombolytic therapy for carotid and vertebrobasilar stroke may result in a more rapid clot lysis and higher recanalization rates than can be achieved with intravenous thrombolysis and thus may warrant the more invasive and time-consuming therapeutic approach. We present an overview of all hitherto completed trials of intra-arterial thrombolytic therapy for carotid and vertebrobasilar artery stroke including recommendations for therapy and a meta-analysis. Furthermore, new imaging techniques such as diffusion- and perfusion-weighted magnetic resonance imaging and their impact on patient selection are discussed. Finally, phase IV trials of thrombolysis in general and cost efficacy analyses are presented.

DATA SOURCES

We performed an extensive literature search not only to identify the larger and well-known randomized trials but also to identify smaller pilot studies and case series. Trials included in this review, among others, are the PROACT I and PROACT II studies and the Cochrane Library report.

CONCLUSION

Intra-arterial thrombolytic therapy of acute M1 and M2 occlusions with 9 mg/2 hrs pro-urokinase significantly improves outcome if administered within 6 hrs after stroke onset. Seven patients need to be treated to prevent one patient from death or dependence. Vertebrobasilar occlusion has a grim prognosis and intra-arterial thrombolytic therapy to date is the only life-saving therapy that has demonstrated benefit with regard to mortality and outcome, albeit not in a randomized trial. New magnetic resonance imaging techniques may facilitate and improve the selection of patients for thrombolytic therapy. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public and professional education to regard stroke as a treatable emergency. If applied more widely, thrombolytic therapy may result in profound cost savings in health care and reduction of long-term disability of stroke patients.

Management of neurological complications of carotid artery stenting

PURPOSE

To review the neurological complications associated with extracranial carotid artery stenting and to preliminarily assess techniques used to manage these complications.

METHODS

Between April 1994 and August 2000, 450 patients (270 men; mean age 70.2 years, range 27-89) had stents implanted to treat 472 cervical carotid artery stenoses. Over half (257, 57%) of the patients were symptomatic. A variety of stents were implanted percutaneously after predilation of the lesion; a third of the patients received glycoprotein IIb/ IIIa inhibitors intraprocedurally in addition to a standard oral antiplatelet regimen (aspirin and ticlopidine or clopidogrel). Occurrence and management of neurological complications within the 30-day periprocedural period were reviewed.

RESULTS

There were 14 (3.1%) transient ischemic attacks (TIAs), 10 (2.2%) minor strokes, and 3 (0.7%) major strokes. Among 6 (1.3%) procedure-related deaths, 4 had neurological causes. The total stroke and death rate was 4.2% (n = 19). All the TIAs, 4 of which occurred between 1 and 14 days poststenting, were treated medically, as were the minor strokes, 3 of which occurred >24 hours after stenting. Only 2 minor stroke patients had mild residual upper extremity motor deficits. Intra-arterial thrombolytic therapy was administered in 5 cases (2 major strokes survivors and 3 patients who suffered a neurologically-related death); occlusions were identified in the proximal middle cerebral artery (MCA) in 3 and the distal MCA in 2. Angiographic improvement was noted in 4 (80%), but only the 2 (40%) with distal MCA occlusions did well clinically.

CONCLUSIONS

Neurological complications following carotid artery stenting are inevitable. The occurrence of minor strokes >24 hours following stenting may indicate a possible late embolic phenomenon, which warrants investigation. Likewise, the marginal efficacy of intra-arterial thrombolytic therapy demonstrates an inability to lyse embolic plaque and underscores the need for effective distal protection.

Selective Intra-arterial Thrombolysis for Embolic Complications of Cerebral Endovascular Therapy

SUMMARY

Cerebral thrombo-embolic complications seldom occur during intracranial endovascular therapeutic procedures. Yet, despite a systemic preventive regimen of pre-operative intravenous acetylsalicylic acid and effective systemic heparinisation, we encountered seven complications of this type over a period of five years, a 3.7 per thousand incidence (7/1858). Local intra-arterial thrombolysis performed immediately after the thrombo-embolic complication resulted in complete recanalization in five cases and partial recanalization in two. CT scans performed 24 hours after thrombolysis were normal in six of the seven patients. Only one female patient with partial recanalization showed a limited cortical infarct in the parietal distribution of the middle cerebral artery territory. In all seven cases recanalization of the occluded vessel resulted in a return to the baseline initial neurological status. This short series demonstrates the usefulness of emergent thrombolysis dealing with the thrombo-embolic complications of angiography or endovascular therapy. These results are in agreement with these experimental data showing that early recanalization can prevent macroscopically visible infarcts.

Evidence-based treatment of patients with ischemic cerebrovascular disease

The results of trials that study patients with defined lesions (atrial fibrillation without valvular heart disease, various severities of carotid artery stenosis in the neck, intracranial artery stenosis) are very helpful for clinicians caring for patients with those conditions. On the other hand, trials that group all patients with brain ischemia together are not very helpful. Modern technology now makes it possible to define quickly and safely: (1) the location, nature, and severity of causative cerebrovascular, cardiac, and aortic lesions; (2) blood constituents and coagulability; and, (3) the presence, location, and severity of ischemic brain damage. As in all medicine, treatment should be aimed at the cause of disease, not the time course and severity of present damage. Clearly, more trials are needed in patients who have been studied thoroughly using modern technology. Until then, clinicians must understand the context of the trial data to determine if the results are applicable to Mr. or Ms. Jones, and the patients sitting before them in the office or in the hospital bed.

Quantitative measurement of cerebral blood flow by (99m)Tc-HMPAO SPECT in acute ischaemic stroke: usefulness in determining therapeutic options

OBJECTIVE

Early recanalisation by thrombolysis is a conclusive therapy for acute ischaemic stroke. But this therapy may increase the risk of intracerebral haemorrhage or severe brain oedema. The purpose was to evaluate usefulness of quantitative measurement of cerebral blood flow by single photon emission computed tomography (SPECT) in predicting the risk of haemorrhage or oedema, and determining the therapeutic options in acute hemispheric ischaemic stroke.

METHODS

The relation was studied retrospectively between initial regional cerebral blood flow (rCBF) quantitatively measured by technetium-99m-labelled hexamethylpropyleneamine oxime ((99m)Tc-HMPAO) SPECT and final clinical and radiological outcome in 20 patients who presented hemispheric ischaemic stroke and were treated conservatively or received early recanalisation by local intra-arterial thrombolysis. The non-invasive Patlak plot method was used for quantitative measurement of rCBF by SPECT.

RESULTS

Regions where residual rCBF was preserved over 35 ml/100 g/min had a low possibility of infarction without recanalisation and regions where residual rCBF was preserved over 25 ml/100 g/min could be recovered by early recanalisation. However, regions where residual rCBF was severely decreased (< 20 ml/100 g/min) had a risk of intracerebral haemorrhage and severe oedema.

CONCLUSIONS

A quantitative assessment of residual rCBF by (99m)Tc-HMPAO SPECT is useful in predicting the risk of haemorrhage or severe oedema in acute ischaemic stroke. Therapeutic options should be determined based on the results of rCBF measurement.

Postischemic intracarotid treatment with TNK-tPA reduces infarct volume and improves neurological deficits in embolic stroke in the unanesthetized rat

BACKGROUND AND PURPOSE

To simulate human stroke, we developed a model of focal cerebral embolic ischemia in the unanesthetized rat. Using this model, we tested the hypothesis that intra-arterial administration of TNK-tPA, a fibrin specific second generation thrombolytic agent, is effective in reducing ischemic volume without increasing intra-cerebral hemorrhage.

METHODS

Under anesthesia, a catheter was inserted to the origin of the MCA of male Wistar rats. Forty-five minutes after recovery from anesthesia, the MCA was occluded in the awake rat by a single fibrin rich clot placed via the catheter. TNK-tPA (1.5 mg/kg) was administered intraarterially via the catheter at either 2 h or 4 h after stroke. All rats were sacrificed at 48 h after ischemia. Neurological deficits, gross hemorrhage and ischemic lesion volume were measured.

RESULTS

A clot was detected at the origin of the MCA 4 h after MCA occlusion in the awake rats (n=4). Rats (n=12) subjected to MCA occlusion showed immediate neurological deficits which persisted for 48 h of ischemia. Ischemic rats had a lesion volume of 38.2+/-3.8% and 25% of rats exhibited gross hemorrhage. Ischemic rats (n=10) treated with TNK-tPA at 2 h showed a significant (P<0.05) reduction of neurological deficits, body weight loss and infarct volume (22.8+/-2.1%) without an increase in gross hemorrhage (10%) compared with the non treated ischemic rats (25%). Although treatment with TNK-tPA of ischemic rats (n=12) at 4 h did not significantly (P=0.06) reduce infarct volume (28.6+/-3.0%), it also did not increase gross hemorrhage (25%) compared with the control group (25%).

CONCLUSIONS

This study demonstrates that intraarterial administration of TNK-tPA at 2 h of ischemia in the unanesthesthetized rat is effective in reducing neurological deficits and ischemic lesion volume without increasing hemorrhagic transformation and that administration of TNK-tPA at 4 h of ischemia does not increase the incidence of hemorrhagic transformation.

Antithrombotic treatments in acute ischemic stroke

Ischemic stroke results most commonly from cerebral arterial thrombosis. Antithrombotic agents can reduce the incidence of cerebral embolic events or the extent of tissue injury and neurological outcome. The antiplatelet agents aspirin, ticlopidine, and the combination of dipyridamole and aspirin are associated with a significant reduction in second focal cerebral ischemic events. Oral anticoagulants have a role to reduce the incidence of cardiogenic emboli in patients with mechanical cardiac valves or nonvalvular atrial fibrillation. Both antithrombotics are untested in the acute setting. The recombinant tissue plasminogen activator rt-PA has been shown to significantly increase the number of stroke patients with no or minimal deficit when treated within 3 hours of symptom onset. Additional studies of this and other plasminogen activators by both intravenous and intra-arterial delivery have highlighted limitations to this approach, but also support its role in acute intervention. The risk of intracerebral hemorrhage attends the use of all antithrombotic agents, most notably plasminogen activators. Strategies to decrease this risk are likely to add to beneficial outcome.