Treating patients with 'wake-up' stroke: the experience of the AbESTT-II trial

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

Pharmacological Strategies for Stroke Intervention: Assessment of Pathophysiological Relevance and Clinical Trials

OBJECTIVES

The present review describes stroke pathophysiology in brief and discusses the spectrum of available treatments with different promising interventions that are in clinical settings or are in clinical trials.

METHODS

Relevant articles were searched using Google Scholar, Cochrane Library, and PubMed. Keywords for the search included ischemic stroke, mechanisms, stroke interventions, clinical trials, and stem cell therapy.

RESULTS AND CONCLUSION

Stroke accounts to a high burden of mortality and morbidity around the globe. Time is an important factor in treating stroke. Treatment options are limited; however, agents with considerable efficacy and tolerability are being continuously explored. With the advances in stroke interventions, new therapies are being formulated with a hope that these may aid the ongoing protective and reparative processes. Such therapies may have an extended therapeutic time window in hours, days, weeks, or longer and may have the advantage to be accessible by a majority of the patients.

Stroke thrombectomy complication management

Endovascular mechanical thrombectomy (EVT) is widely accepted as the first-line treatment for acute ischemic stroke in patients with large vessel occlusion. Being an invasive treatment, this method is associated with various preoperative, perioperative, and postoperative complications. These complications may influence peri-interventional morbidity and mortality and therefore treatment efficacy and clinical outcome. The aim of this review is to discuss the most common types of complications associated with EVT, the probable mechanisms of injury, and effective methods to manage and prevent complications.

Neuroimaging Paradigms to Identify Patients for Reperfusion Therapy in Stroke of Unknown Onset

Despite the proven efficacy of intravenous alteplase or endovascular thrombectomy for the treatment of patients with acute ischemic stroke, only a minority receive these treatments. This low treatment rate is due in large part to delay in hospital arrival or uncertainty as to the exact time of onset of ischemic stroke, which renders patients outside the current guideline-recommended window of eligibility for receiving these therapeutics. However, recent pivotal clinical trials of late-window thrombectomy now force us to rethink the value of a simplistic chronological formulation that “time is brain.” We must recognize a more nuanced concept that the rate of tissue death as a function of time is not invariant, that still salvageable tissue at risk of infarction may be present up to 24 h after last-known well, and that those patients may strongly benefit from reperfusion. Multiple studies have sought to address this clinical dilemma using neuroimaging methods to identify a radiographic time-stamp of stroke onset or evidence of salvageable ischemic tissue and thereby increase the number of patients eligible for reperfusion therapies. In this review, we provide a critical analysis of the current state of neuroimaging techniques to select patients with unwitnessed stroke for revascularization therapies and speculate on the future direction of this clinically relevant area of stroke research.

Expanding the concept of neuroprotection for acute ischemic stroke: The pivotal roles of reperfusion and the collateral circulation

This review surveys the efforts taken to achieve clinically efficacious protection of the ischemic brain and underscores the necessity of expanding our purview to include the essential role of cerebral perfusion and the collateral circulation. We consider the development of quantitative strategies to measure cerebral perfusion at the regional and local levels and the application of these methods to elucidate flow-related thresholds of ischemic viability and to characterize the ischemic penumbra. We stress that the modern concept of neuroprotection must consider perfusion, the necessary substrate upon which ischemic brain survival depends. We survey the major mechanistic approaches to neuroprotection and review clinical neuroprotection trials, focusing on those phase 3 multicenter clinical trials for acute ischemic stroke that have been completed or terminated. We review the evolution of thrombolytic therapies; consider the lessons learned from the initial, negative multicenter trials of endovascular therapy; and emphasize the highly successful positive trials that have finally established a clinical role for endovascular clot removal. As these studies point to the brain's collateral circulation as key to successful reperfusion, we next review the anatomy and pathophysiology of collateral perfusion as it relates to ischemic infarction, as well as the molecular and genetic influences on collateral development. We discuss the current MR and CT-based diagnostic methods for assessing the collateral circulation and the prognostic significance of collaterals in ischemic stroke, and we consider past and possible future therapeutic directions.

Neurological Fallacies Leading to Malpractice: A Case Studies Approach

A young woman presents with an intracranial arachnoid cyst. Another is diagnosed with migraine headache. An elderly man awakens with a stroke. And a baby delivered vaginally after 2 hours of questionable electronic fetal monitoring patterns grows up to have cerebral palsy. These seemingly disparate cases share a common underlying theme: medical myths. Myths that may lead not only to misdiagnosis and treatment harms but to seemingly never-ending medical malpractice lawsuits, potentially culminating in a settlement or judgment against an unsuspecting neurologist. This article provides a case studies approach exposing the fallacies and highlighting proper management of these common neurologic presentations.

Stroke- on- Awakening: Safety of CT-CTA Based Selection for Reperfusion Therapy

BACKGROUND

We studied the safety of use of acute reperfusion therapies in patients with stroke- on- awakening using a computed tomographic angiography (Cta) based large vessel occlusion-good scan paradigm in clinical routine.

METHODS

the Cta database of the Calgary stroke program was reviewed for the period January 2003-March 2010. patients with stroke-on-awakening with large artery occlusions on Cta, who received conservative, iV thrombolytic and/or endovascular treatment at discretion of the attending stroke neurologist were analyzed. time of onset was defined by the time last seen or known to be normal. Baseline non-contrast Ct scan (nCCt) alberta Stroke program early Ct Score (aSpeCtS) > 7 was considered a good scan. hemorrhage was defined on follow-up brain imaging using eCaSS 3 criteria. independence (mrS≤2) at three months was considered a good clinical outcome. Standard descriptive statistics and multivariable analysis were done.

RESULTS

among 532 patients with large artery occlusions, 70 patients with stroke-on-awakening (13.1%) were identified. the median age was 69.5 (iQr 24) and 41 (58.6%) were female; 41 (58.6%) received anti-platelets only and 29 (41.4%) received thrombolytic treatment [iV-12 (17.1%), iV/ia-12 (17.1%) and ia-5(7.1%)]. unadjusted analysis showed that baseline nCCt aSpeCtS ≤ 7 (p=0.002) and higher nihSS scores (p=0.018) were associated with worse outcomes. there were no ph2 hemorrhages in the iV thrombolytic or endovascular treated group. functional outcome was not different by treatment.

CONCLUSION

When carefully selected using Ct –Cta, by a good scan (aSpeCtS > 7) occlusion paradigm, acute reperfusion therapies in patients with stroke-on-awakening can be performed safely in clinical routine.

A Stroke Registry Data on the Use of Intravenous Recombinant Tissue Plasminogen Activator in Stroke of Unknown Time of Onset

BACKGROUND

Stroke of unknown time of onset (SUTO) constitutes one fifth of all ischemic stroke admissions, and routine use of intravenous recombinant tissue plasminogen activator (IV rtPA) is recommended only in patients with a symptom onset time of less than 4.5 hours. There are limited data on clinical outcome in patients with SUTO versus patients with symptoms onset less than 4.5 hours from onset time. We hypothesized that efficacy and safety outcomes of IV rtPA therapy in selected SUTO patients are comparable to those with known onset time.

METHODS

We compared 90 days' modified Rankin Scale (mRS), rates of symptomatic intracerebral hemorrhage (sICH), in-hospital mortality, and death due to sICH between 3 groups treated with IV rtPA: SUTO, 3 hours or less, and 3.0-4.5 hours from prospective patient admissions between April 1, 2012, and July 31, 2013.

RESULTS

There were 65 participants in the SUTO group, 186 in the 3 hours or less group, and 51 in the 3.0-4.5 hours group. In-hospital mortality rates were 14.5%, 13.5%, and 11.8%, respectively. sICH risks were 1.5%, 1.6%, and 5.8%, and death rates due to sICH were 0%, 1.1%, and 1.9%, respectively. Ninety days' odds of excellent clinical outcome (mRS score 0-1) were not different between the SUTO group (odds ratio [OR] 1.14, 95% confidence interval [CI]: .63-2.10), the 3 hours or less group (OR .87, 95% CI: .48-1.60), and the 3.0-4.5 hours group (OR .79, 95% CI: .48-1.60) (P = .82).

CONCLUSION

Thrombolytic therapy outcome in SUTO is not different from in-license use in our patient population. There is an urgent need to include this patient group in ongoing randomized multicenter trials.

Wake-up stroke: Dawn of a new era

Wake-up stroke or stroke with unclear onset of symptoms is known to occur in one-fourth of ischemic stroke patients. These patients are not considered for thrombolytic therapy based on time designation of their symptom onset as per the current guidelines. Observational studies have investigated the pathophysiology and suggested actual onset of symptoms to be approximate to the awakening time for these patients. Use of advanced imaging modalities in these patients tends to identify favorable patient profiles for thrombolysis. Results of the ongoing trials will likely beckon a seminal juncture in stroke therapy and deliver critical modifications in the current treatment guidelines for thrombolysis in this substantial, yet neglected, group of stroke patients. In this article, we have reviewed the predisposing factors, preferred imaging modalities and various ongoing thrombolytic and endovascular trials to date for patients with unclear time of symptom onset or who wake up with stroke symptoms.

"Timing" of arrival and in-hospital mortality in a cohort of patients under anticoagulant therapy presenting to the emergency departments with cerebral hemorrhage: A multicenter chronobiological study in Italy

Therapy with oral anticoagulants (OACs) is a risk factor for cerebral hemorrhage (CH). Although different studies have been undertaken to investigate the timing of the onset of major cardiovascular events, no data exist on temporal patterns of the onset of CH in subjects treated with OACs. The aim of this study is to evaluate the timing of CH in patients treated with OACs. All patients who developed CH under OACs therapy and admitted to 28 Italian Emergency Departments (EDs) between September 2011 and July 2013 were enrolled. Age, sex, time and location of the hemorrhagic lesion, type of the bleeding events (idiopathic or post-traumatic), anticoagulant therapy (warfarin or new oral anticoagulants - NOAs) and time of ED admission (i.e., hour, day, month and season) were recorded. Five hundred and seventeen patients (63.2% male aged 80 ± 7.9 yrs) with CH were involved. Warfarin was taken by 494 patients (95.6%), and NOAs by 23 (4.4%). In-hospital mortality (IHM) was recorded in 208 cases (40.2%). Cosinor analysis showed a peak of CH arrival between 12:00 and 14:00 h both in the whole population (PR 73.9%, p = 0.002) and the male subgroup (PR 65.2%, p = 0.009), whereas females showed an anticipated morning peak between 08:00 and 10:00 h (PR 65.7%, p = 0.008). A further analysis between idiopathic and post-traumatic CH confirmed the presence of a 24 h pattern with a peak between 12:00 and 14:00 h (PR 58.5%, p = 0.019) and between 08:00 and 10:00 h (PR80.1%, p < 0.001) for idiopathic events and post-traumatic hemorrhages, respectively. Moreover, a seasonal winter peak was identified for idiopathic forms (PR 74%, p = 0.035), and a summer peak for post-traumatic forms (PR 77%, p = 0.025). The present study suggests the presence of a temporal pattern of ED arrivals in CH patients treated with OACs.

Computed tomography perfusion-based thrombolysis in wake-up stroke

Wake-up stroke (WUS) patients are typically excluded from reperfusion treatment, as the time of symptoms onset is unknown. The purpose of this study is to evaluate the clinical outcome and safety of intravenous thrombolysis with rt-PA in patients with WUS eligible for therapy using computed tomography perfusion criteria (CTP), compared to patients treated with rt-PA within 4.5 h of symptoms onset (non-WUS). This is an experimental, open-label trial, controlled against the best therapy currently in use. Primary endpoints were functional independence after 3 months [modified Rankin scale (mRS) ≤ 1] for clinical outcome and symptomatic intracerebral hemorrhage (SICH) for safety. Secondary endpoints were no or only mild disability after 3 months (mRS ≤ 2) for clinical outcome, total intracerebral hemorrhage (TICH) and contrast-induced nephropathy (CIN) for safety. 170 patients were treated, 143 non-WUS patients and 27 patients with WUS. Strokes of cardioembolic origin were most common in WUS patients (p < 0.001). Primary endpoints: mRS ≤ 1 was found in 35.8 % (non-WUS: 36.4% vs. WUS 33.3%; p = 0.62) and SICH was observed in 3.4 % of non-WUS patients and in WUS patients (p = 0.32). Secondary endpoints: mRS ≤ 2 was observed in 66.4 % of patients (non-WUS: 67.1% vs. WUS 62.9%; p = 0.67), TICH in 13.5 % of patients (13.9 % non-WUS vs. 11.1 % WUS; p = 0.69). CIN was documented in 3.7 % of WUS patients. rt-PA treatment carried out in WUS patients selected on the basis of CTP data demonstrate comparable clinical outcome and safety with respect to non-WUS patients. The study supports the hypothesis that a selected group of WUS patients may be suitable for thrombolysis.

Favorable Bridging Therapy Based on DWI-FLAIR Mismatch in Patients with Unclear-Onset Stroke

BACKGROUND AND PURPOSE

Standard selection criteria for revascularization therapy usually exclude patients with unclear-onset stroke. Our aim was to evaluate the efficacy and safety of revascularization therapy in patients with unclear-onset stroke in the anterior circulation and to identify the predictive factors for favorable clinical outcome.

MATERIALS AND METHODS

We retrospectively analyzed 41 consecutive patients presenting with acute stroke with unknown time of onset treated by intravenous thrombolysis and/or mechanical thrombectomy. Only patients without well-developed fluid-attenuated inversion recovery changes of acute diffusion lesions on MR imaging were enrolled. Twenty-one patients were treated by intravenous thrombolysis; 19 received, simultaneously, intravenous thrombolysis and mechanical thrombectomy (as a bridging therapy); and 1 patient, endovascular therapy alone. Clinical outcome was evaluated at 90 days by using the mRS. Mortality and symptomatic intracranial hemorrhage were also reported.

RESULTS

Median patient age was 72 years (range, 17-89 years). Mean initial NIHSS score was 14.5 ± 5.7. Successful recanalization (TICI 2b-3) was assessed in 61% of patients presenting with an arterial occlusion, symptomatic intracranial hemorrhage occurred in 2 patients (4.9%), and 3 (7.3%) patients died. After 90 days, favorable outcome (mRS 0-2) was observed in 25 (61%) patients. Following multivariate analysis, initial NIHSS score (OR, 1.43; 95% CI, 1.13-1.82; P = .003) and bridging therapy (OR, 37.92; 95% CI, 2.43-591.35; P = .009) were independently associated with a favorable outcome at 3 months.

CONCLUSIONS

The study demonstrates the safety and good clinical outcome of acute recanalization therapy in patients with acute stroke in the anterior circulation and an unknown time of onset and a DWI/FLAIR mismatch on imaging. Moreover, bridging therapy versus intravenous thrombolysis alone was independently associated with favorable outcome at 3 months.

Coagulation factor XIIIa is inactivated by plasmin

Coagulation factor XIIIa (FXIIIa) is a transglutaminase that covalently cross-links fibrin and other proteins to fibrin to stabilize blood clots and reduce blood loss. A clear mechanism to describe the physiological inactivation of FXIIIa has been elusive. Here, we show that plasmin can cleave FXIIIa in purified systems and in blood. Whereas zymogen FXIII was not readily cleaved by plasmin, FXIIIa was rapidly cleaved and inactivated by plasmin in solution (catalytic efficiency = 8.3 × 10(3) M(-1)s(-1)). The primary cleavage site identified by mass spectrometry was between K468 and Q469. Both plasma- and platelet-derived FXIIIa were susceptible to plasmin-mediated degradation. Inactivation of FXIIIa occurred during clot lysis and was enhanced both in plasma deficient in fibrinogen and in plasma treated with therapeutic levels of tissue plasminogen activator. These results indicate that FXIIIa activity can be modulated by fibrinolytic enzymes, and suggest that changes in fibrinolytic activity may influence cross-linking of blood proteins.

What to do With Wake-Up Stroke

Wake-up stroke, defined as the situation where a patient awakens with stroke symptoms that were not present prior to falling asleep, represents roughly 1 in 5 acute ischemic strokes and remains a therapeutic dilemma. Patients with wake-up stroke were excluded from most ischemic stroke treatment trials and are often not eligible for acute reperfusion therapy in clinical practice, leading to poor outcomes. Studies of neuroimaging with standard noncontrast computed tomography (CT), magnetic resonance imaging (MRI), and multimodal perfusion-based CT and MRI suggest wake-up stroke may occur shortly before awakening and may assist in selecting patients for acute reperfusion therapies. Pilot studies of wake-up stroke treatment based on these neuroimaging features are promising but have limited generalizability. Ongoing randomized treatment trials using neuroimaging-based patient selection may identify a subset of patients with wake-up stroke that can safely benefit from acute reperfusion therapies.

IV thrombolysis for treatment of patients with stroke upon awakening: Yes? No?

Current guidelines recommend IV administration of recombinant tissue plasminogen activator (rtPA) to carefully selected patients who can be treated within 4.5 hours of ischemic stroke onset. Patients whose neurologic symptoms are discovered upon awakening (wake-up stroke) generally are not given rtPA because of the uncertainty about the time of stroke onset. This group of patients may be relatively large. Preliminary reports suggest that patients with wake-up stroke who can be treated within 4.5 hours of discovery may respond similarly to patients with an established time of stroke onset. Clinical trials, which are selecting patients to treat primarily based on imaging surrogates, are under way. Pending the results of these trials, data about the utility of clinical or imaging findings that would identify those patients who could be treated and information about the safety and efficacy of IV rtPA in this situation are not available.

Early statin use in ischemic stroke patients treated with recanalization therapy: retrospective observational study

BACKGROUND

We aimed to determine whether early statin use following recanalization therapy improves the functional outcome of ischemic stroke.

METHODS

Using a prospective stroke registry database, we identified a consecutive 337 patients within 6 h of onset who had symptomatic stenosis or occlusion of major cerebral arteries and received recanalization therapy. Based on commencement of statin therapy, patients were categorized into administration on the first (D1, 13.4%), second (D2, 20.8%) and third day or later (D ≥ 3, 15.4%) after recanalization therapy, and no use (NU, 50.4%). The primary efficacy outcome was a 3-month modified Rankin Scale score of 0-1, and the secondary outcomes were neurologic improvement, neurologic deterioration and symptomatic hemorrhagic transformation during hospitalization.

RESULTS

Earlier use of statin was associated with a better primary outcome in a dose-response relationship (P for trend = 0.01) independent of premorbid statin use, stroke history, atrial fibrillation, stroke subtype, calendar year, and methods of recanalization therapy. The odds of a better primary outcome increased in D1 compared to NU (adjusted odds ratio, 2.96; 95% confidence interval, 1.19-7.37). Earlier statin use was significantly associated with less neurologic deterioration and symptomatic hemorrhagic transformation in bivariate analyses but not in multivariable analyses. Interaction analysis revealed that the effect of early statin use was not altered by stroke subtype and recanalization modality (P for interaction = 0.97 and 0.26, respectively).

CONCLUSION

Early statin use after recanalization therapy in ischemic stroke may improve the likelihood of a better functional outcome without increasing the risk of intracranial hemorrhage.

Antiplatelet drugs: which targets for which treatments?

The current standard care for acute coronary syndromes is dual antiplatelet therapy combining the COX1 inhibitor aspirin with a drug targeting the P2Y12 receptor, together with anticoagulation during and after early revascularization by percutaneous intervention. In very high-risk patients, glycoprotein (GP) IIb/IIIa antagonists may also be used. Secondary prevention of ischemic events requires dual antiplatelet therapy for several months followed by lifelong low-dose aspirin. The duration of treatment and the drugs to combine nevertheless remain matters of debate and the focus of ongoing research. Despite great progress, there is still room for improved efficacy and this could involve new targets for both antiplatelet drugs (like the thrombin receptor PAR1) and anticoagulants. However, improved efficacy is offset by an increased risk of bleeding. Stroke patients are still waiting for better treatment, their bleeding risk being particularly high. New targets including the collagen receptor, glycoprotein VI (GPVI), and the GPIb-von Willebrand factor axis, governing platelet interaction with the diseased vessel wall, should enable us to complete the armamentarium of antiplatelet drugs.

Wake-up Strokes Are Similar to Known-Onset Morning Strokes in Severity and Outcome

BACKGROUND

Stroke symptoms noticed upon waking, wake-up stroke, account for up to a quarter of all acute ischemic strokes. Patients with wake-up stroke, however, are often excluded from thrombolytic therapy.

METHODS

Using our prospectively collected stroke registry, wake-up stroke and known-onset morning strokes were identified. Wakeup stroke was defined as a patient who was asleep >3 hours and first noted stroke symptoms upon awakening between 0100 and 1100. Known-onset morning stroke was defined as a patient who had symptom onset while awake during the same time interval. We compared wake-up stoke to known-onset morning stroke with respect to patient demographics, stroke severity, etiology and outcomes.

RESULTS

One-quarter of patients with acute ischemic strokes (391/1415) had documented time between 0100 and 1100 of symptom onset: 141 (36%) wake-up strokes and 250 (64%) known-onset morning strokes. No difference in baseline characteristics, stroke severity, stroke etiology, neurologic deterioration, discharge disposition or functional outcome was detected. Known-onset morning stroke patients were significantly more likely to get thrombolytic therapy and have higher risk of in-hospital mortality. Wake-up stroke patients tended to be older, have higher diastolic blood pressure and have longer length of hospital stay.

DISCUSSION

While patients with wake-up stroke were similar to patients with known-onset morning stroke in many respects, patients with known onset morning stroke were significantly more likely to get treated with thrombolytic therapy and have higher in-hospital mortality.

Wake-up stroke and stroke of unknown onset: a critical review

Patients, who wake up with an ischemic stroke, account for a large number of the total stroke population, due to circadian morning predominance of stroke. Currently, this subset of patients is excluded from revascularization-therapy since no exact time of onset is known. A large group of these patients might be eligible for therapy. In this review, we assessed the current literature about the hypothesis that wake-up-strokes occur just prior on awakening and if this subgroup differs in characteristics compared to the overall stroke population. We looked at the safety and efficacy of thrombolysis and interventional techniques in the group of patients with unknown stroke-onset. We performed a meta-analysis of the diagnostic accuracy of the diffusion-FLAIR mismatch in identifying stroke within 3 and 4.5 h. The different imaging-selection criteria that can be used to treat these patients are discussed. Additional research on imaging findings associated with recent stroke and penumbral imaging will eventually lead to a shift from a rigid time-frame based therapy to a tissue-based individualized treatment approach.

Update in the management of acute ischemic stroke

Acute ischemic stroke is the fourth leading cause of death and the leading cause of disability in the United States. Stroke is a medical emergency. The development of stroke systems of care has changed the way practitioners view and treat this devastating disease. Ample evidence has shown that patients presenting early and receiving intravenous thrombolytic therapy have the best chance for significant improvement in functional outcome, particularly if they are transported to specialized stroke centers. Early detection and management of medical and neurologic complications is key at preventing further brain damage in patients with acute ischemic stroke.

Glycoprotein IIb-IIIa inhibitors for acute ischaemic stroke

BACKGROUND

Glycoprotein (GP) IIb-IIIa inhibitors are antiplatelet agents that act by antagonising GP IIb-IIIa receptors on the platelet surface and block the final common pathway to platelet aggregation by preventing the binding of fibrinogen molecules that form bridges between adjacent platelets. Thus, GP IIb-IIIa inhibitors could favour endogenous thrombolysis by reducing thrombus growth and preventing thrombus re-formation through competitive inhibition with fibrinogen and, due to their mechanism of action, are likely to have a more profound antiplatelet effect with more rapid onset than conventional antiplatelet agents, such as aspirin or clopidogrel. Currently used in clinical practice for the treatment of individuals with acute coronary syndromes and during coronary angioplasty, GP IIb-IIIa inhibitors could also be useful for the treatment of people with acute ischaemic stroke.

OBJECTIVES

To assess the use of GP IIb-IIIa inhibitors in people with acute ischaemic stroke to evaluate whether such treatments (1) reduce the proportion of patients who die or remain dependent, and (2) are sufficiently safe for general use. We wished to examine the effects GP IIb-IIIa inhibitors alone or in combination with thrombolytic agents.

SEARCH METHODS

We searched the Cochrane Stroke Group trials register (last searched 10 June 2013), MEDLINE (1966 to June 2013), EMBASE (1980 to June 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 5, 2013), and major ongoing clinical trials registers (June 2013). We also searched reference lists and contacted trial authors and pharmaceutical companies.

SELECTION CRITERIA

We aimed to analyse unconfounded randomised controlled trials (RCTs) of GP IIb-IIIa inhibitors in the treatment of people with acute ischaemic stroke. Only individuals who started treatment within six hours of stroke onset were included.

DATA COLLECTION AND ANALYSIS

We independently selected trials for inclusion, assessed trial quality and extracted the data.

MAIN RESULTS

We included four trials involving 1365 participants. Three trials compared the intravenous GP IIb-IIIa inhibitor Abciximab with intravenous placebo (1215 participants) and one trial compared the intravenous GP IIb-IIIa inhibitor Tirofiban with intravenous aspirin (150 participants). Treatment with either of these GP IIb-IIIa inhibitors did not significantly reduce long-term death or dependency (odds ratio (OR) 0.97, 95% confidence interval (CI) 0.77 to 1.22, for the comparison between Abciximab and placebo; OR 1.00, 95% CI 0.52 to 1.92, for the comparison between Tirofiban and aspirin) and had no effect on deaths from all causes (OR 1.08, 95% CI 0.77 to 1.53, for the comparison between Abciximab and placebo; OR 1.00, 95% CI 0.35 to 2.82, for the comparison between Tirofiban and aspirin). Abciximab was associated with a significant increase in symptomatic intracranial haemorrhage (OR 4.6, 95% CI 2.01 to 10.54) and with a non-significant increase in major extracranial haemorrhage (OR 1.81, 95% CI 0.96 to 3.41), whereas the only small trial comparing Tirofiban with aspirin showed no increased risk of bleeding complications with Tirofiban (OR 0.32, 95% CI 0.03 to 3.19, for symptomatic intracranial haemorrhage; OR 3.04, 95% CI 0.12 to 75.83, for major extracranial haemorrhages). There was no significant inconsistency across the studies.

AUTHORS' CONCLUSIONS

The available trial evidence showed that, for individuals with acute ischaemic stroke, GP IIb-IIIa inhibitors are associated with a significant risk of intracranial haemorrhage with no evidence of any reduction in death or disability in survivors. These data do not support their routine use in clinical practice. The conclusion is driven by trials of Abciximab, which contributed 89% of the total number of study participants considered.

Intravenous thrombolysis in ischemic stroke with unknown onset using CT perfusion

BACKGROUND

Acute ischemic stroke patients with unclear onset time presenting >4.5 h from last-seen-normal (LSN) time are considered late patients and excluded from i.v. thrombolysis. We aimed to evaluate whether this subgroup of patients is different from patients presenting >4.5 h from a witnessed onset, in terms of eligibility and response to computed tomography perfusion (CTP)-guided i.v. thrombolysis.

METHODS

We prospectively studied consecutive acute non-lacunar middle cerebral artery (MCA) ischemic stroke patients presenting >4.5 h from LSN. All patients underwent multimodal CT and were considered eligible for i.v. thrombolysis according to CTP criteria. Two patient groups were established based on the knowledge of the stroke onset time. We compared the proportion of candidates suitable for intravenous thrombolysis between both groups, and their outcome after thrombolytic therapy.

RESULTS

Among 147 MCA ischemic stroke patients presenting >4.5 h from LSN, stroke onset was witnessed in 74 and unknown in 73. Thirty-seven (50%) patients in the first group and 32 (44%) in the second met CTP criteria for thrombolysis (P = 0.7). Baseline variables were comparable between both groups with the exception of age, which was higher in the unclear onset group. The rates of early neurological improvement (54.1% vs 46.9%), 2-h MCA recanalization (43.5% vs 37%), symptomatic hemorrhagic transformation (3% vs 0%) and good 3-month functional outcome (62.2% vs 56.3%) did not differ significantly between both groups.

CONCLUSION

Delayed stroke patients with unknown onset time were no different than patients >4.5 h regarding eligibility and response to CTP-based i.v. thrombolysis.

Safety and effectiveness of endovascular treatment of stroke with unknown time of onset

BACKGROUND

Currently, treatment options for patients with strokes with unknown time of onset (UKO) remain limited. With the advance of neuroimaging and endovascular treatment (EVT), selected patients might have a chance of a therapeutic option. We sought to compare clinical outcome after EVT in patients with known time of stroke onset (KO) and in those with UKO.

METHODS

We prospectively registered consecutive patients with acute large artery occlusion of the anterior territory who underwent EVT. Multimodal MR or Alberta Stroke Program early CT score (ASPECTS) and transcranial color-coded Duplex sonography were used to select patients for EVT. Recanalization, periprocedural complications, intracranial hemorrhage (ICH) and outcome were recorded. Symptomatic ICH (sICH) was defined as a worsening of ≥4 points in the National Institutes of Health Stroke Scale (NIHSS) score within 36 h in any bleeding. Favorable outcome was defined as a modified Rankin score ≤2 at 3 months.

RESULTS

A total of 141 patients were studied, 109 with KO and 32 with UKO. Mean age was 66.5 versus 64.7 years (p = 0.005) and median baseline NIHSS was 18 versus 17 (p = 0.095), respectively. Prior IV tPA was more frequently administered to KO patients (62.4 vs. 9.4%, p < 0.001), whereas patient selection using multimodal MR was more frequent in patients with UKO (78.1 vs. 45.4%, p < 0.001). Median time from stroke onset or from the last time the patient was seen well to groin puncture and to recanalization was significantly longer in patients with UKO, but no differences were found in the duration of the procedure. For KO/UKO patients recanalization was seen in 77.1 vs. 65.7% (p = 0.084), sICH occurred in 10 versus 0% (p = 0.061) and favorable outcome at 3 months was achieved in 41.3 versus 50% (p = 0.382), respectively.

CONCLUSIONS

Clinical outcomes in this series of EVT in ischemic stroke patients due to large anterior arterial occlusion with salvageable brain are similar for patients treated with KO and UKO. These data support a randomized study of EVT in extended or uncertain time windows..

Advancing care for traumatic brain injury: findings from the IMPACT studies and perspectives on future research

Research in traumatic brain injury (TBI) is challenging for several reasons; in particular, the heterogeneity between patients regarding causes, pathophysiology, treatment, and outcome. Advances in basic science have failed to translate into successful clinical treatments, and the evidence underpinning guideline recommendations is weak. Because clinical research has been hampered by non-standardised data collection, restricted multidisciplinary collaboration, and the lack of sensitivity of classification and efficacy analyses, multidisciplinary collaborations are now being fostered. Approaches to deal with heterogeneity have been developed by the IMPACT study group. These approaches can increase statistical power in clinical trials by up to 50% and are also relevant to other heterogeneous neurological diseases, such as stroke and subarachnoid haemorrhage. Rather than trying to limit heterogeneity, we might also be able to exploit it by analysing differences in treatment and outcome between countries and centres in comparative effectiveness research. This approach has great potential to advance care in patients with TBI.

Negative fluid-attenuated inversion recovery-based intravenous thrombolysis using recombinant tissue plasminogen activator in acute stroke patients with unknown onset time

BACKGROUND

Approximately 25% of acute stroke patients were excluded from intravenous thrombolysis using recombinant tissue plasminogen activator (IV-tPA) because of unknown onset time. Recent studies have shown that patients with unknown onset time would be able to receive IV-tPA when showing no ischemia on fluid-attenuated inversion recovery (negative FLAIR). The present study evaluated the safety and feasibility of IV-tPA in patients with unknown onset time and negative FLAIR compared to those with standard IV-tPA.

METHODS

Stroke patients with unknown onset time were prospectively enrolled. Only patients with an occlusion of the internal carotid artery (ICA) and/or middle cerebral artery (M1 and M2) with a Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Score (DWI-ASPECTS) ≥5 were analyzed. IV-tPA was performed within 3 h from the 'first found abnormal time' if the patient showed negative FLAIR. Standard IV-tPA patients were extracted from our registry as controls after having been matched by age and occluded artery to the negative FLAIR (N-F) group.

RESULTS

Twenty patients in the N-F group and 60 in the control group were included. National Institutes of Health Stroke Scale (NIHSS) scores [median 18 (interquartile range 13-20) vs. 17 (12-20), p = 0.609] and DWI-ASPECTS [9 (7-9) vs. 8 (5-9), p = 0.213] were similar between the 2 groups. ICA occlusion was seen in 35%, M1 in 50%, and M2 in 15% in both groups. None of the N-F group and 1 (2%) of the control group experienced symptomatic intracerebral hemorrhage (p = 1.000). Recanalization within 1 h after IV-tPA was achieved in 6 (30%) patients in the N-F group and 24 (40%) in the control group (p = 0.595). Recanalization at 24 h after IV-tPA was seen in 13 (65%) patients in the N-F group and 43 (72%) in the control group (p = 0.584). At 7 days, 8 (40%) in the N-F group and 28 (47%) in the control group had a dramatic recovery (defined as a ≥10-point reduction in the total NIHSS score or a score of 0 or 1) (p = 0.796). At 3 months, a favorable outcome (modified Rankin scale score, 0-2) was seen in 47% in the N-F group and 33% in the control group (p = 0.365).

CONCLUSION

IV-tPA in negative FLAIR patients with unknown onset time appears safe and feasible.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.

Reperfusion therapy in unclear-onset stroke based on MRI evaluation (RESTORE): a prospective multicenter study

BACKGROUND AND PURPOSE

Unclear-onset strokes are generally excluded from time-based thrombolytic therapy. We examined the safety and feasibility of magnetic resonance imaging-based reperfusion therapy in unclear-onset stroke.

METHODS

This prospective, multicenter, single-arm study screened consecutive unclear-onset stroke patients within 6 hours of symptom detection. Patients with perfusion-diffusion mismatch>20% and negative or subtle fluid-attenuated inversion recovery changes were treated with intravenous tissue plasminogen activator, intra-arterial therapy, or a combination. The safety outcome was symptomatic intracranial hemorrhage within 48 hours after treatment. The primary efficacy outcome was a 3-month modified Rankin Scale score of 0 to 2. Controls were untreated unclear-onset stroke patients prospectively captured in stroke registries.

RESULTS

Of 430 unclear-onset stroke patients, 83 (19.3%) received reperfusion therapy (mean age, 67.5±10.4 years; males, 66.3%; median baseline National Institutes of Health Stroke Scale, 14). Symptomatic intracranial hemorrhage with any neurological decline developed in 5 patients (6.0%). Symptomatic intracranial hemorrhage with National Institutes of Health Stroke Scale worsening ≥4 developed in 3 patients (3.6%). Thirty-seven patients (44.6%) achieved modified Rankin Scale score of 0 to 2, and 24 (28.9%) had modified Rankin Scale score of 0 to 1. Female, baseline National Institutes of Health Stroke Scale score, no immediate or early recanalization, and more white blood cells were independent predictors of poor outcome. Compared with untreated controls, the treated group was significantly associated with good outcomes of modified Rankin Scale score of 0 to 2 after adjusting for age, sex, and baseline National Institutes of Health Stroke Scale in logistic regression analysis (odds ratio, 2.25; 95% CI, 1.14-4.49).

CONCLUSIONS

In unclear-onset stroke patients, magnetic resonance imaging-based reperfusion therapy was feasible and safe. Randomized controlled trials are warranted to confirm the benefit of reperfusion therapy for unclear-onset stroke.

Presentation and outcomes of "wake-up strokes" in a large randomized stroke trial: analysis of data from the International Stroke Trial

BACKGROUND

Recent studies comparing the outcomes of wake-up stroke (WUS) and stroke while awake (SWA) patients reveal better outcomes among SWA patients, attributable in part to their higher rates of thrombolysis. Patients with WUS are largely excluded from therapy. Earlier analyses, conducted before the approval of alteplase for acute stroke, show the true divergence of natural histories between these 2 groups.

METHODS

We analyzed 17,398 patients with ischemic stroke from the International Stroke Trial and compared both presentations and outcomes between the WUS and SWA groups. Severity was assessed by level of consciousness, Oxfordshire Community Stroke Project (OCSP) stroke classification, number of neurologic deficits, and predicted probability of dependency or death. Outcomes were assessed at day 14 and at 6 months. Outcome assessments were controlled for potential confounders.

RESULTS

WUS represented 29.6% of all ischemic strokes. More severe OSCP stroke type (total anterior circulation syndrome) was less common in WUS. Although more patients with WUS were alert at presentation with a lower predicted probability of dependency, the 14-day mortality rates and rates of poor outcome at 6 months were similar between the 2 groups.

CONCLUSIONS

WUS patients comprise one quarter to one third of ischemic stroke patients. Despite their more benign presentations, they deteriorate to outcome rates similar to SWA. Although they are typically excluded from time-dependent acute interventions, patients with WUS may benefit from acute intervention to prevent this worsening natural history.

A pragmatic approach using magnetic resonance imaging to treat ischemic strokes of unknown onset time in a thrombolytic trial

BACKGROUND AND PURPOSE

Toward the goal of designing a clinical trial using imaging parameters to treat stroke patients with unknown onset time, we investigated the timing of changes on MRI in patients with well-defined stroke onset.

METHODS

Hypothesis-generating (n=85) and confirmatory (n=111) samples were scored by blinded readers for fluid-attenuated inversion recovery (FLAIR) hyperintensity in diffusion-positive regions. Reader-measured signal intensity ratio (SIR) of the lesion to contralateral tissue was compared with SIR measured by coregistration.

RESULTS

Lesion conspicuity increased with time on FLAIR (P=0.006). Qualitative assessment of FLAIR-negative vs FLAIR hyperintensity (k=0.7091; 95% CI, 0.61-0.81) showed good interrater agreement. Subtle hyperintensity was less reliably categorized (k=0.59; 95% CI, 0.47-0.71). Reader-measured SIR <1.15 can identify patients within the treatable time window of 4.5 hours (positive predictive value=0.90). The SIR was greater for right hemisphere lesions (P=0.04) for a given reported time from stroke symptom onset.

CONCLUSIONS

The SIR on FLAIR provides a quantitative tool to identify early ischemic strokes. In developing SIR thresholds, right hemisphere lesions may confound the accurate estimate of stroke onset time. Image coregistration for thrombolytic trial enrollment is not necessary. A SIR <1.15 on FLAIR yields a practical estimate of stroke onset within 4.5 hours.

Wake-up or unclear-onset strokes: are they waking up to the world of thrombolysis therapy?

Wake-up or unclear-onset strokes occur in up to one-fourth of patients with ischemic stroke. Although stroke severity and clinical outcomes appear to be poorer in wake-up strokes than nonwake-up strokes, many patients with wake-up strokes do not receive thrombolytic therapy because stroke onset time cannot be determined. Recent studies have suggested, however, that the actual onset time of wake-up stroke is close to the wake-up time. Furthermore, advanced imaging technologies may enable us to identify patients with favorable risk-benefit profiles for thrombolysis. Indeed, empirical thrombolytic treatments have suggested safety and feasibility of such therapy in these patients. Based on these promising results and the development of multimodal imaging methods, prospective thrombolysis trials using predefined imaging criteria are currently under way to test the safety and efficacy of thrombolysis in patients with wake-up or unclear-onset strokes. The establishment of optimal acute treatment strategies in this important yet so far neglected group of patients is eagerly awaited.

Wake-up stroke within 3 hours of symptom awareness: imaging and clinical features compared to standard recombinant tissue plasminogen activator treated stroke

BACKGROUND

Patients with wake-up stroke (WUS) are excluded from thrombolysis because of unknown time of symptom onset. Previous studies have reported similar stroke severity and early ischemic changes (EICs) in patients with WUS and stroke of known onset. These studies, however, included patients within a large timeframe to imaging or did not quantify EICs. The aim of our study was to quantify EICs of patients with WUS presenting within 3 hours of symptom recognition compared to standard 3-hours recombinant tissue plasminogen activator (rt-PA)-treated patients and assess the extent of ischemic lesion and functional independence at follow-up.

METHODS

Patients were selected from our prospectively collected stroke database. Baseline and follow-up computed tomographic scans were graded with Alberta Stroke Program Early Computed Tomography Score (ASPECTS). Clinical outcome measures were modified Rankin Scale score, mortality, and symptomatic intracerebral hemorrhage.

RESULTS

Demographic features, risk factors, stroke severity, and baseline ASPECTS were similar in both groups. WUS and rt-PA-treated patients had similar tissue outcome (median ASPECTS 7.0 vs 7.5; P = .202). Functional outcome was more favorable in rt-PA-treated patients (61.6% vs 43.1%; odds ratio [OR] 2.12; 95% confidence interval [CI] 1.05-4.28; P = .037). After adjusting for age, stroke severity, treatment, and EICs in less than one-third of middle cerebral artery territory, rt-PA and National Institutes of Health Stroke Scale scores remained the only significant predictors of outcome (OR 7.76; 95% CI 2.40-25.05; P = .001 and OR 0.74; 95% CI 0.67-0.82; P < .001, respectively).

CONCLUSIONS

Within 3 hours of symptom recognition, patients with WUS have EICs similar to rt-PA-treated patients. It is reasonable to expect that selected WUS patients might benefit from thrombolysis within 3 hours of symptom awareness.

Impact of tissue plasminogen activator on the neurovascular unit: from clinical data to experimental evidence

About 15 million strokes occur each year worldwide. As the number one cause of morbidity and acquired disability, stroke is a major drain on public health-care funding, due to long hospital stays followed by ongoing support in the community or nursing-home care. Although during the last 10 years we have witnessed a remarkable progress in the understanding of the pathophysiology of ischemic stroke, reperfusion induced by recombinant tissue-type plasminogen activator (tPA-Actilyse) remains the only approved acute treatment by the health authorities. The objective of the present review is to provide an overview of our present knowledge about the impact of tPA on the neurovascular unit during acute ischemic stroke.

Perfusion-CT guided intravenous thrombolysis in patients with unknown-onset stroke: a randomized, double-blind, placebo-controlled, pilot feasibility trial

INTRODUCTION

Patients with unknown stroke onset are generally excluded from acute recanalisation treatments. We designed a pilot study to assess feasibility of a trial of perfusion computed tomography (PCT)-guided thrombolysis in patients with ischemic tissue at risk of infarction and unknown stroke onset.

METHODS

Patients with a supratentorial stroke of unknown onset in the middle cerebral artery territory and significant volume of at-risk tissue on PCT were randomized to intravenous thrombolysis with alteplase (0.9 mg/kg) or placebo. Feasibility endpoints were randomization and blinded treatment of patients within 2 h after hospital arrival, and the correct application (estimation) of the perfusion imaging criteria.

RESULTS

At baseline, there was a trend towards older age [69.5 (57-78) vs. 49 (44-78) years] in the thrombolysis group (n = 6) compared to placebo (n = 6). Regarding feasibility, hospital arrival to treatment delay was above the allowed 2 h in three patients (25%). There were two protocol violations (17%) regarding PCT, both underestimating the predicted infarct in patients randomized in the placebo group. No symptomatic hemorrhage or death occurred during the first 7 days. Three of the four (75%) and one of the five (20%) patients were recanalized in the thrombolysis and placebo group respectively. The volume of non-infarcted at-risk tissue was 84 (44-206) cm(3) in the treatment arm and 29 (8-105) cm(3) in the placebo arm.

CONCLUSIONS

This pilot study shows that a randomized PCT-guided thrombolysis trial in patients with stroke of unknown onset may be feasible if issues such as treatment delays and reliable identification of tissue at risk of infarction tissue are resolved. Safety and efficiency of such an approach need to be established.

Population-based study of wake-up strokes

OBJECTIVE

Previous studies have estimated that wake-up strokes comprise 8%to 28% of all ischemic strokes, but these studies were either small or not population-based. We sought to establish the proportion and event rate of wake-up strokes in a large population-based study and to compare patients who awoke with stroke symptoms with those who were awake at time of onset.

METHODS

First-time and recurrent ischemic strokes among residents of the Greater Cincinnati/Northern Kentucky region (population 1.3 million) in 2005 were identified using International Classification of Diseases-9 codes 430-436 and verified via study physician review. Ischemic strokes in patients aged 18 years and older presenting to an emergency department were included. Baseline characteristics were ascertained, along with discharge modified Rankin Scale scores and 90-day mortality.

RESULTS

We identified 1,854 ischemic strokes presenting to an emergency department, of which 273 (14.3%) were wake-up strokes. There were no differences between wake-up strokes and all other strokes with regard to clinical features or outcomes except for minor differences in age and baseline retrospective NIH Stroke Scale score. The adjusted wake-up stroke event rate was 26.0/100,000. Of the wake-up strokes, at least 98 (35.9%) would have been eligible for thrombolysis if arrival time were not a factor.

CONCLUSIONS

Within our population, approximately 14% of ischemic strokes presenting to an emergency department were wake-up strokes. Wake-up strokes cannot be distinguished from other strokes by clinical features or outcome. We estimate that approximately 58,000 patients with wake-up strokes presented to an emergency department in the United States in 2005.

Ischemic stroke during sleep: its association with worse early functional outcome

BACKGROUND AND PURPOSE

Approximately one fourth of stroke occur during sleep. Despite the clinical and radiological similarities between wake-up stroke (WUS) and non-WUS, the functional outcomes of WUS are largely unknown.

METHODS

This retrospective analysis reviewed 2289 consecutive patients with acute ischemic stroke who were admitted between November 2002 and December 2009. We used 3 end-point analytic techniques to evaluate the association between WUS and functional outcomes: dichotomized analysis for "functional dependency" (a discharge modified Rankin Scale [mRS] score ≥2 regardless of initial stroke severity), severity-adjusted responder analysis for "unfavorable outcome" (a discharge mRS ≥1 for an admission National Institutes of Health Stroke Scale score 0 to 7; mRS ≥2 for National Institutes of Health Stroke Scale 8 to 14; or mRS ≥3 for National Institutes of Health Stroke Scale ≥15), and shift analysis for changes in overall distributions of discharge mRS scores.

RESULTS

The initial National Institutes of Health Stroke Scale score of patients with WUS was significantly higher than that of their non-WUS counterparts (median [interquartile range]; 4 [2 to 7] versus 3 [1 to 6]; P<0.01). The dichotomized analysis strategy failed to detect a significant association between WUS and functional dependency at discharge (adjusted OR, 0.99; 95% CI, 0.76 to 1.28). However, the responder analysis showed that patients with WUS were more likely to have "unfavorable outcomes" (adjusted OR, 1.33; 95% CI, 1.02 to 1.72), and the shift analysis also detected significant effect of WUS on the mRS score distributions toward increased dependency (adjusted OR, 1.22; 95% CI, 1.01 to 1.48).

CONCLUSIONS

From our study, we documented that WUS was associated with worse short-term outcomes after ischemic stroke. Careful selection of appropriate analytic techniques may help to detect modest associations in observational studies.

Imaging stroke patients with unclear onset times

Stroke is a leading cause of death and adult morbidity worldwide. By defining stroke symptom onset by the time the patient was last known to be well, many patients whose onsets are unwitnessed are automatically ineligible for thrombolytic therapy. Advanced brain imaging may serve as a substitute witness to estimate stroke onset and duration in those patients who do not have a human witness. This article reviews and compares some of these imaging-based approaches to thrombolysis eligibility, which can potentially expand the use of thrombolytic therapy to a broader population of acute stroke patients.

Alberta Stroke Program Early CT Score (ASPECTS) in patients with wake-up stroke

One-quarter of ischemic strokes occur during sleep, and affected patients are excluded from thrombolytic therapy because of an unknown time of stroke onset. It has been suggested that early ischemic changes detected on computed tomography (CT) are similar in patients with acute stroke and patients who recently awoke with stroke. We compared head CT scans using the Alberta Stroke Program Early CT Score (ASPECTS) in patients who were likely to suffer their stroke during sleep (awoke group) and a control group of patients with stroke of known onset time. Patients were recruited from a prospectively collected acute stroke database. The awoke group was defined as all ischemic stroke patients who were "last seen normal" more than 4 hours ago, arrived between 4 a.m. and 10 a.m., and underwent head CT within 15 hours of the time last seen normal. The control group was randomly selected from patients who underwent head CT within 4 hours of stroke onset. The ASPECTS evaluations were performed by investigators blinded to patient group and time of onset. A modified Rankin Scale (mRS) score was available in 15 awoke patients and 46 control patients at 90 days after stroke. Twenty-eight awoke patients and 68 control patients had suitable imaging for the ASPECTS. Baseline demographic characteristics and risk factors were similar in the 2 groups. The dichotomized ASPECTS analysis (≤7 vs 8-10) showed no significant differences between the groups. ASPECTS was 8-10 in 89.3% the awoke group and 95.6% in the control group (P=.353). There was a trend toward higher 90-day mRS score (0-1) in the awoke group versus controls (73% vs 45%; P=.079). Initial ASPECTS was similar in patients with wake-up stroke and those with 4 hours of symptoms. This suggests that a subset of wake-up stroke patients might be suitable for thrombolytic therapy.

Feasibility and safety of magnetic resonance imaging-based thrombolysis in patients with stroke on awakening: initial single-centre experience

BACKGROUND

Up to 25% of all acute ischaemic strokes occur during sleep. Because of the unclear time window, patients with stroke on awakening are usually not considered for acute therapy and excluded from most acute treatment trials.

AIM

To evaluate the feasibility of magnetic resonance imaging-based intravenous thrombolysis in patients with stroke on awakening in a routine clinical setting.

METHODS

Forty-five patients with stroke on awakening clinically qualifying for intravenous thrombolysis and presenting within 6 h after symptom recognition were admitted to our institution between October 2006 and May 2008. Following an institutional protocol, patients received magnetic resonance imaging as a first-line imaging modality and were offered mismatch-based thrombolysis whenever possible. Baseline demographic data, clinical, laboratory and imaging findings were analysed. Outcome was assessed using the modified Rankin Scale score at 3 months.

RESULTS

Magnetic resonance imaging screening was feasible in 43/45 patients (96%). After screening, 10 patients (22%) were treated with intravenous thrombolysis. There were no differences between treated and untreated patients regarding cardiovascular risk factors, stroke aetiology, previous prophylactic treatment and symptom recognition to door time or door to imaging time. Outcome was comparable in both groups despite a trend towards more severe strokes in the intravenous thrombolysis group. Only one asymptomatic and no symptomatic haemorrhage were observed.

CONCLUSION

Our data demonstrate that magnetic resonance imaging-based thrombolysis is feasible and possibly safe in patients with stroke on awakening (SOA). Randomised clinical trials for patients with stroke on awakening are needed to further test the safety and efficacy of intravenous thrombolysis in this patient group. The results of our study may help to initiate and design such studies.