Stroke Mimics and Acute Stroke Evaluation: Clinical Differentiation and Complications after Intravenous Tissue Plasminogen Activator

Neuroimaging for differential diagnosis of transient neurological attacks

BACKGROUND

Rapid yet comprehensive neuroimaging protocols are required for patients with suspected acute stroke. However, stroke mimics can account for approximately one in five clinically diagnosed acute ischemic strokes and the rate of thrombolyzed mimics can be as high as 17%. Therefore, to accurately determine the diagnosis and differentiate mimics from true transient ischemic attacks, acute ischemic stroke is a challenge to every clinician.

DISCUSSION

Medical history and neurological examination, noncontract head computed tomography, and routine magnetic resonance imaging play important roles in the assessment and management of patients with transient neurological attacks in the emergency department. This review attempts to summarize how neuroimaging can be utilized to help differentiate the most common mimics from transient ischemic attack and acute ischemic stroke.

CONCLUSION

Although imaging can help direct critical triage decisions for intravenous thrombolysis or endovascular therapy, more detailed medical history and neurological examination are crucial for making a prompt and accurate diagnosis for transient neurological attack patients.

Neck pain and absence of cranial nerve symptom are clues of cervical myelopathy mimicking stroke: Two case reports

BACKGROUND

Cervical myelopathy is a potential stroke imitator, for which intravenous thrombolysis would be catastrophic.

CASE SUMMARY

We herein present two cases of cervical myelopathy. The first patient presented with acute onset of right hemiparesis and urinary incontinence, and the second patient presented with sudden-onset right leg monoplegia. The initial diagnoses for both of them were ischemic stroke. However, both of them lacked cranial nerve symptom and suffered neck pain at the beginning of onset. Their cervical spinal cord lesions were finally confirmed by cervical computed tomography. A literature review showed that neck pain and absence of cranial nerve symptom are clues of cervical myelopathy.

CONCLUSION

The current report and the review remind us to pay more attention to these two clues in suspected stroke patients, especially those within the thrombolytic time window.

Multilayer perceptron-based prediction of stroke mimics in prehospital triage

The identification of stroke mimics (SMs) in patients with stroke could lead to delayed diagnosis and waste of medical resources. Multilayer perceptron (MLP) was proved to be an accurate tool for clinical applications. However, MLP haven't been applied in patients with suspected stroke onset within 24 h. Here, we aimed to develop a MLP model to predict SM in patients. We retrospectively reviewed the data of patients with a prehospital diagnosis of suspected stroke between July 2017 and June 2021. SMs were confirmed during hospitalization. We included demographic information, clinical manifestations, medical history, and systolic and diastolic pressure on admission. First, the cohort was randomly divided into a training set (70%) and an external testing set (30%). Then, the least absolute shrinkage and selection operator (LASSO) method was used in feature selection and an MLP model was trained based on the selected items. Then, we evaluated the performance of the model using the ten-fold cross validation method. Finally, we used the external testing set to compare the MLP model with FABS scoring system (FABS) and TeleStroke Mimic Score (TM-Score) using a receiver operator characteristic (ROC) curve. In total, 402 patients were included. Of these, 82 (20.5%) were classified as SMs. During the ten-fold cross validation, the mean area under the ROC curve (AUC) of 10 training sets and 10 validation sets were 0.92 and 0.87, respectively. In the external testing set, the AUC of the MLP model was significantly higher than that of the FABS (0.855 vs. 0.715, P = 0.038) and TM-Score (0.855 vs. 0.646, P = 0.006). The MLP model had significantly better performance in predicting SMs than FABS and TM-Score.

Clinical Differences Between Stroke and Stroke Mimics in Code Stroke Patients

BACKGROUND

The code stroke system is designed to identify stroke patients who may benefit from reperfusion therapy. It is essential for emergency physicians to rapidly distinguish true strokes from stroke mimics to activate code stroke. This study aimed to investigate the clinical and neurological characteristics that can be used to differentiate between stroke and stroke mimics in the emergency department (ED).

METHODS

We conducted a retrospective observational study of code stroke patients in the ED from January to December 2019. The baseline characteristics and the clinical and neurological features of stroke mimics were compared with those of strokes.

RESULTS

A total of 409 code stroke patients presented to the ED, and 125 (31%) were diagnosed with stroke mimics. The common stroke mimics were seizures (21.7%), drug toxicity (12.0%), metabolic disorders (11.2%), brain tumors (8.8%), and peripheral vertigo (7.2%). The independent predictors of stroke mimics were psychiatric disorders, dizziness, altered mental status, and seizure-like movements, while current smoking, elevated systolic blood pressure, atrial fibrillation on the initial electrocardiogram, hemiparesis as a symptom, and facial palsy as a sign suggested a stroke. In addition, the likelihood of a stroke in code stroke patients tended to increase as the number of accompanying deficits increased from the following set of seven focal neurological deficits: hemiparesis (or upper limb monoparesis), unilateral limb sensory change, facial palsy, dysarthria, aphasia (or neglect), visual field defect, and oculomotor disorder (P < 0.001).

CONCLUSION

Some clinical and neurological characteristics have been identified to help differentiate stroke mimics from true stroke. In particular, the likelihood of stroke tended to increase as the number of accompanying focal neurological deficits increased.

Predictors of perfusion computed tomography alterations in stroke mimics attended as stroke code

BACKGROUND AND PURPOSE

Stroke mimics (SMs) account for a significant number of patients attended as stroke code (SC) with an increasing number over the years. Recent studies show perfusion computed tomography (PCT) alterations in some SMs, especially in seizures. The objective of our study was to evaluate the clinical characteristics and PCT alterations in SMs attended as SC in order to identify potential predictors of PCT alterations in SMs.

METHODS

A retrospective study was performed including all SC activations undergoing a multimodal CT study including non-enhanced computed tomography (CT), CT angiography and PCT, as part of our SC protocol, over 39 months. Patients with a final diagnosis of SM after complete diagnosis work-up were therefore selected. Clinical variables, diagnosis, PCT alteration patterns and type of map affected (T_max or time to peak, cerebral blood flow and cerebral blood volume) were registered.

RESULTS

Stroke mimics represent up to 16% (284/1761) of SCs with a complete multimodal study according to our series. Amongst SMs, 26% (74/284) showed PCT alterations. PCT abnormalities are more prevalent in seizures and status epilepticus and the main pattern is alteration of the time to peak map, of unilateral hemispheric distribution or of non-vascular territory. In our series, the independent predictors of alteration in PCT in SMs are aphasia, female sex and older age.

CONCLUSIONS

Perfusion computed tomography alterations can be found amongst almost a third of SMs attended as SC, especially older women presenting with aphasia with a final diagnosis of epileptic seizures and status epilepticus.

Cost-Effectiveness of Emergent MRI during Stroke Alert to Diagnose Stroke Mimics: Single-Center Experience

Objective  The aim of this article was to assess the role of emergent magnetic resonance imaging (MRI) for stroke mimics during a stoke alert (within 45 minutes) in reducing direct cost of management and duration of inpatient stay.

Methods  We did a retrospective chart review of all the patients who received emergent MRI brain during a stroke alert to help make decision about intravenous tissue-type plasminogen activator (IV tPA) administration from January 2013 to December 2015. Using the patient financial resource data and with the help of billing department, we calculated the approximate money saved in taking care of the patients who may have received IV tPA if emergent MRI brain was not available to diagnose stroke mimics as they presented with acute neurologic deficit within IV tPA time window.

Results  Ninety seven out of 1,104 stroke alert patients received emergent MRI. Of these only 17 (17.5%) were diagnosed with acute ischemic stroke (AIS), and 80 (82.5%) as stroke mimics. By doing emergent MRI for suspected stroke mimics, our study showed an approximate total saving of $1,005,720 to $1,384,560, that is, $12,571 to $17,307 per patient in medical expenditure.

Discussion  We suggest modification of stroke pathway from current algorithm “CT+CTA≥IV-tPA/neurointervention≥MRI” to “MRI+MRA≥IV-tPA/neurointervention” for possible stroke mimics, which can reduce the cost, radiation exposure, and duration of hospital stay for stroke mimics.

Conclusion  Emergent MRI is a cost-effective tool to evaluate IV-tPA eligibility for suspected stroke mimics during a stroke alert.

Stroke-mimics in stroke-units. Evaluation after changes imposed by randomized trials

BACKGROUND

A larger therapeutic window for stroke treatment requires a significant change in the organization of emergency services, avoiding the increase in number of imaging exams and indirectly the time to treatment.

OBJECTIVE

To highlight the relation between faster clinical evaluation and stroke over-suspicion and consequently excessive imaging acquisition. To identify predictors of ischemic stroke and stroke mimics (SM), aiming for better patient selection for comprehensive neuroimaging and reperfusion therapies.

METHODS

Retrospective, cohort, observational, single-center study that reviewed all consecutive files of patients presenting with acute neurological symptoms who underwent CT scan or MRI from July 1, 2016 to July 1, 2017.

RESULTS

736 patient files were reviewed. 385 patients (52.3%) presented with confirmed acute ischemic infarct, 93 (12.6%) had another brain lesion mimicking acute ischemia, and 258 (35.1%) had normal imaging. Acute stroke was more frequent in elderly patients with atrial fibrillation, arterial hypertension, or dysarthria or right motor impairment. Stroke mimic was associated with female patients with low vascular risk factors, low NIHSS, and patients with decreased level of consciousness or symptoms suggestive of posterior circulation.

DISCUSSION

47.7% of all patients seen at the stroke unit did not have acute stroke lesions. Clinical assessment data have been used to provide indicators of acute stroke and stroke mimic patients, and symptoms corresponding to acute stroke and stroke mimic seem to be similar in the literature.

CONCLUSION

Considering that the number of patients admitted for stroke treatment will increase even further with a larger therapeutic window for mechanical thrombectomy and for thrombolysis, a diagnostic decision-making algorithm for stroke patients is required in order to reinforce the suspicion of stroke indicating an urgent MRI.

A Helpful Tool in Diagnosing Stroke Mimics: Arterial Spin Labeled Perfusion Magnetic Resonance Imaging

BACKGROUND

Prompt and effective management of acute ischemic stroke in the emergency setting requires a high level of suspicion and accurate diagnosis. Conversely, identifying stroke mimics can be challenging, given the similarity of their clinical symptomatology, the necessary rapid assessment and triage, and the overall frenetic pace inherent in the goal of rapid thrombolysis ("time is brain").

CASE REPORT

We describe a case that involves an elderly patient with acute hemiplegia and dysarthria. Given these concerning symptoms, and multiple preexisting cerebrovascular risk factors (including paroxysmal atrial fibrillation), a "stroke alert" was issued. Imaging was negative for infarct and she was ultimately diagnosed with hemiplegic migraine based on her symptoms and impressive findings on a novel magnetic resonance sequence called arterial spin labeled (ASL) perfusion. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Identifying a nonischemic etiology in a presumed stroke patient, while often difficult, can obviate unnecessary treatment, improve patient care, and promote appropriate resource allocation. As imaging and treatment of cerebrovascular disease advances, the optimization of multidisciplinary care should incorporate neuroradiologists informing and availing their clinical colleagues of applications of an ever-expanding imaging armamentarium. This case is an excellent example of both a common challenging stroke mimic and the potential benefits of ASL perfusion imaging in refining and expediting accurate diagnosis. In addition, it serves as a more general introduction to the particular strengths of this noninvasive, noncontrast magnetic resonance technique, which can be employed to assess varied emergent neuropathology.

Aglaia odorata Lour. extract inhibit ischemic neuronal injury potentially via suppressing p53/Puma-mediated mitochondrial apoptosis pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Aglaia odorata Lour. is a traditional Chinese medicinal plant possessing properties of improving blood circulation, and it is widely used in the treatment of dizziness, traumatic injuries and bruises.

AIM OF STUDY

In this study, we are aimed to investigate the cerebral protection effect of the extracts from leaves of Aglaia odorata Lour. (ELA) and the potential mechanism in vivo and in vitro.

MATERIALS AND METHODS

The therapeutic effect of ELA on ischemic cerebral stroke was measured on a middle cerebral artery occlusion (MCAO) rat model. Protective effect of ELA on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cells was measured by MTT assay. The apoptotic cells were observed by Hoechst 33258 staining and acridine orange/ethidium bromide double staining assay. Mitochondria were observed by Mitotracker staining assay. The mitochondrial membrane potential was determined by JC-1 staining assay. Western blot was used to investigate the effects of ELA on apoptosis-related proteins.

RESULTS

We showed that ELA was an effective neuroprotective agent. In vivo experiments, ELA exerted significant protective effect on MCAO model. TTC staining showed that ELA could reduce cerebral infarction area against MCAO insult. HE and Nissl's staining indicated that ELA could reverse the damage of cortex and hippocampus caused by MCAO. In vitro experiments, ELA showed significant protective effect on OGD/R-induced PC12 cells by reducing the number of apoptotic cells, increasing mitochondrial membrane potential, and reducing superoxide aggregation, further suppressing mitochondrial caspase-9/3 apoptosis pathway. Moreover, protective effect of ELA on mitochondrial function may be exerted by inhibiting p53/Puma signal pathway.

CONCLUSION

Our results suggest that ELA exerts a marked neuroprotective effect against cerebral ischemia potentially via suppressing p53/Puma-mediated mitochondrial caspase-9/3 apoptosis pathway.

Alcohol Intoxication as a Stroke Mimic and the Incidence of Acute Alcohol Intoxication in Stroke

BACKGROUND AND AIM

Alcohol intoxication can be a posterior circulation stroke mimic as they share symptoms such as dysarthria, gait disturbances and nystagmus. We describe alcohol intoxication as a stroke mimic and the frequency of acute alcohol intoxication among stroke patients.

METHODS

Prospective observational single-center study (2014-2017, Haga Ziekenhuis, the Hague). In all patients older than 16 years presenting as possible acute stroke less than 6 hours of onset, blood ethanol was measured; greater than 0.1 blood alcohol concentration (BAC) was considered elevated.

RESULTS

In total 974 patients were included: 60 (6%) had elevated blood ethanol (mean: 1.3 BAC). In 180 of 974 patients (18%) a stroke mimic was diagnosed: 12 were due to alcohol intoxication (1% of total cohort, 7% of stroke mimic, mean ethanol level: 2.2 BAC). Half of these patients denied or downplayed their alcohol consumption. Stroke and concurrent alcohol intoxication occurred in 38 of 794 strokes (5%, mean ethanol level: 1.1 BAC). Compared to other stroke patients, these 38 patients presented more often after working hours (mean 6.38pm versus 2.23pm) and received alteplase and endovascular therapy less often (24% versus 43%, P = .018 and 3% versus 10%, P = .241, respectively).

CONCLUSIONS

Of all patients presenting as possible acute stroke, 6% also drank alcohol. 18% of the whole cohort was diagnosed with a stroke mimic. Acute alcohol intoxication as sole diagnosis was diagnosed in 1% of the total cohort and 7% of stroke mimics, 50% denied or downplayed their alcohol consumption. 5% of all stroke patients also drank alcohol, they were significantly less likely to receive alteplase or endovascular treatment.

Modeling Stroke Patient Transport for All Patients With Suspected Large-Vessel Occlusion

Importance

Ischemic stroke with large-vessel occlusion can be treated with alteplase and/or endovascular therapy; however, the administration of each treatment is time sensitive.

Objective

To identify the optimal triage and transport strategy: direct to the endovascular center (mothership) or immediate alteplase treatment followed by transfer to the endovascular center (drip and ship), for all patients with suspected large-vessel occlusion stroke.

Design Setting, and Participants

This was a theoretical, conditional probability modeling study. Existing data from clinical trials of stroke treatment were used for model generation. The study was conducted from February 1, 2017, to March 1, 2018.

Main Outcomes and Measures

The time-dependent efficacy of alteplase and endovascular therapy and the accuracy of large-vessel occlusion screening tools were modeled to estimate the probability of positive outcome (modified Rankin Scale score, 0-1 at 90 days) for both the drip-and-ship and mothership transport strategies. Based from onset to treatment, the strategy that estimates the greatest probability of excellent outcome is determined in several different scenarios.

Results

The patient's travel time from both thrombolysis and endovascular therapy centers, speed of treatment, and positive predictive value of the screening tool affect whether the drip-and-ship or mothership strategy estimates best outcomes. With optimal treatment times (door-to-needle time: 30 minutes; door-in-door-out time: 50 minutes; door-to-groin-puncture time: 60 minutes [mothership], 30 minutes [drip and ship]), both options estimate similar outcomes when the centers are 60 minutes or less apart. However, with increasing travel time between the 2 centers (90 or 120 minutes), drip and ship is favored if the patient would have to travel past the thrombolysis center to reach the endovascular therapy center or if the patient would arrive outside the alteplase treatment time window in the mothership scenario. Holding other variables constant, if treatment times are slow at the thrombolysis center (door-to-needle time: 60 minutes; door-in-door-out time: 120 minutes), the area where mothership estimates the best outcomes expands, especially when the 2 centers are close together (60 minutes apart or less). The area where mothership estimates the best outcome also expands as the positive predictive value of the screening tool increases.

Conclusions and Relevance

This study suggests that decision making for prehospital transport can be modeled using existing clinical trial data and that these models can be dynamically adapted to changing realities. Based on current median treatment times to realize the full benefit of endovascular therapy on a population level, the study findings suggest that delivery of the treatment should be regionally centralized. The study modeling suggests that transport decision making is context specific and the radius of superiority of the transport strategy changes based on treatment times at both centers, transport times, and the triaging tool used.

Evaluation of a score for the prehospital distinction between cerebrovascular disease and stroke mimic patients

Background

Patients with a sudden onset of focal neurological deficits consistent with stroke, who turn out to have alternative conditions, have been labeled stroke mimics.

Aims

We assessed a recently validated telemedicine-based stroke mimic score (TeleStroke mimic score; TM-score) and individual patient characteristics with regard to its discriminative value between cerebrovascular disease and stroke mimic patients in the in-person, pre-hospital setting.

Methods

We evaluated patients cared for in a mobile stroke unit in Berlin, Germany. We investigated whether the TM-score (comprising six parameters), Face Arm Speech Time test, and individual patient characteristics were able to differentiate cerebrovascular disease from stroke mimic patients.

Results

We included 423 patients (299 (70.7%) cerebrovascular disease and 124 (29.3%) stroke mimic) in the final analysis. A TM-score > 30 indicated a high probability of a cerebrovascular disease and a score ≤15 of a stroke mimic. The TM-score performed well to identify stroke mimics (area under the curve of 0.74 under receiver-operating characteristic curve analysis). The cerebrovascular disease patients were older (74.8 vs. 69.8 years, p = 0.001), had more often severe strokes (NIHSS > 14 25.8% vs. 11.3%, p = 0.001), presented more often with weakness of the face (70.9% vs. 42.7%, p = 0.001) or arm (60.9% vs. 33.9%, p = 0.001), dysarthria (59.5% vs. 40.3%, p < 0.001), history of atrial fibrillation (38.1% vs. 21.0%, p = 0.001), arterial hypertension (78.9% vs. 53.2%, p < 0.001), and less often with seizure (0.7% vs. 21.0%, p < 0.001).

Conclusions

The TM-score and certain patient characteristics can help paramedics and emergency physicians in the field to identify stroke mimic patients and select the most appropriate hospital destination.

Stroke Mimics: The Quest for Leptomeningeal Anastomoses and Isolated Diffusion-Weigthed MR Signal

Stroke is caused by occlusion of a medium- or large-sized vessel in the brain. The treatment with either intravenous or intra-arterial thrombolysis is based on an accurate and time-sensitive diagnosis. On clinical and imaging grounds a number of entities-seizures, toxic-metabolic, infectious, or demyelinating diseases-can mimic stroke. Identifying them is paramount as the treatment differs significantly. Prior imaging reviews have focused on the nonterritorial distribution of these mimics. However, some important questions arise here. Are the vascular territories and their boundaries invariable in the human brain? Where should we draw the lines separating arterial territories? van der Zwan and colleagues addressed these questions decades ago. For him and others, the leptomeningeal anastomoses-a contentious concept for some but increasingly linked to collateral flow in stroke-is an important anatomic structure with significant variations in their distribution and pathophysiology. Variations in blood supply appear larger that traditionally taught. We revisit this concept and entertained their implications in cases of stroke mimics. For instance, the distribution of abnormalities in some toxic-metabolic processes appear to correlate with areas where rich leptomeningeal anastomoses are expected. We will also explore the concept of hyperintense signal on diffusion weighted-imaging with no correlated changes on apparent diffusion coefficient maps. We name this finding as "isolated DWI signal" and lay-out its importance in the recognition of many entities mimicking stroke. Taking together, the discussed anatomic and imaging concepts will help radiologists and clinicians to recognize not only the common but the unusual entities imitating stroke in the emergency room.

Diagnostic accuracy of whole-brain computed tomography perfusion for detection of ischemic stroke in patients with mild neurological symptoms

Mild and minor acute neurological symptoms may lead to diagnostic uncertainty, resulting in a heterogeneous group of patients with true ischemic events and stroke mimics with a potential for poor outcomes. More than half of ischemic stroke patients present as minor strokes (National Institutes of Health Stroke Scale score <6). Whole-brain computed tomography perfusion can be used as a diagnostic test for minor stroke, offering a potential method of reducing diagnostic uncertainty in these patients. We hypothesize that whole-brain computed tomography perfusion imaging features could accurately predict infarction in patients with minor neurological deficits. This retrospective chart review enrolled consecutive patients suspected of acute ischemic stroke with a National Institutes of Health Stroke Scale score <6, who underwent whole-brain computed tomography perfusion and follow-up diffusion-weighted magnetic resonance imaging at our institution. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were calculated for whole-brain computed tomography perfusion, using follow-up diffusion-weighted magnetic resonance imaging as a reference standard. A total of 524 patients (mean age: 67 years; range: 17-96 years; 56% men) met the inclusion criteria. Patients were excluded for non-diagnostic ( n = 25) or missing maps ( n = 8) scans, non-ischemic findings ( n = 7), and lack of follow-up magnetic resonance imaging ( n = 336). The final analysis included 148 patients who underwent diffusion-weighted magnetic resonance imaging. Whole-brain computed tomography perfusion has a sensitivity of 0.57 (95% CI: 0.45-0.69) and a specificity of 0.82 (95% CI: 0.71-0.90). The positive and negative predictive values and positive and negative likelihood ratios were 75%, 67%, 3.09, and 0.53, respectively. Our analysis suggests that although whole-brain computed tomography perfusion may offer some value as an adjunctive test for improving confidence in offering stroke treatment, it is not sufficiently sensitive or specific to accurately predict cerebral infarcts in patients with minor neurological symptoms.

Comorbid Psychiatric Disease Is Associated With Lower Rates of Thrombolysis in Ischemic Stroke

BACKGROUND AND PURPOSE

Intravenous thrombolysis (IVT) improves outcomes after acute ischemic stroke but is underused in certain patient populations. Mental illness is pervasive in the United States, and patients with comorbid psychiatric disease experience inequities in treatment for a range of conditions. We aimed to determine whether comorbid psychiatric disease is associated with differences in IVT use in acute ischemic stroke.

METHODS

Acute ischemic stroke admissions between 2007 and 2011 were identified in the Nationwide Inpatient Sample. Psychiatric disease was defined by International Classification of Diseases, Ninth Revision, Clinical Modification codes for secondary diagnoses of schizophrenia or other psychoses, bipolar disorder, depression, or anxiety. Using logistic regression, we tested the association between IVT and psychiatric disease, controlling for demographic, clinical, and hospital factors.

RESULTS

Of the 325 009 ischemic stroke cases meeting inclusion criteria, 12.8% had any of the specified psychiatric comorbidities. IVT was used in 3.6% of those with, and 4.4% of those without, psychiatric disease (P<0.001). Presence of any psychiatric disease was associated with lower odds of receiving IVT (adjusted odds ratio, 0.80; 95% confidence interval, 0.76-0.85). When psychiatric diagnoses were analyzed separately individuals with schizophrenia or other psychoses, anxiety, or depression each had significantly lower odds of IVT compared to individuals without psychiatric disease.

CONCLUSIONS

Acute ischemic stroke patients with comorbid psychiatric disease have significantly lower odds of IVT. Understanding barriers to IVT use in such patients may help in developing interventions to increase access to evidence-based stroke care.

Clinical Predictors of Stroke Mimics in Patients Treated with Recombinant Tissue Plasminogen Activator according to a Normal Multimodal Computed Tomography Imaging

BACKGROUND

Multimodal computed tomography imaging (MCTI) is increasingly used for rapid assessment of acute stroke. We investigated characteristics and final diagnoses of patients treated with recombinant tissue plasminogen activator (rt-PA) while admission imaging was unremarkable.

METHODS

From our prospectively collected stroke database (2013-2016), we identified consecutive patients treated with rt-PA on the basis of an unremarkable brain MCTI and assessed with a 24-hour follow-up brain magnetic resonance imaging (MRI). Demographic data, medical history, score on the 15-item National Institute of Health Stroke Scale, and final diagnosis were considered. Absence of MRI infarction and alternate diagnosis defined stroke mimics (SMs). Univariable and multivariable logistic regression analyses identified factors predictive of SMs.

RESULTS

Sixty-eight (47.9%) SMs, 63 (44.4%) strokes, and 11 (7.7%) aborted strokes were found. SMs had more often aphasia (P = .003) and hemianopia (P = .0008), whereas upper limb weakness (ULW) (P = .03) and limb ataxia (P = .002) were more prevalent in strokes. Headache (adjusted odds ratio [Adj. OR], 3.89 [95% confidence interval {CI} 1.44-10.47]), relevant history of epilepsy, migraine, dementia or depression (Adj. OR 3.66 [95% CI 1.31-10.18]), unilateral sensory loss (Adj. OR 2.60 [95% CI 1.05-6.45]), and hemianopia (Adj. OR 4.94 [95% CI 1.46-16.77]) were independent predictors of SMs whereas ULW (Adj. OR 3.16 [95% CI 1.28-7.82]) and ataxia (Adj. OR 3.81 [95% CI 1.43-10.13]) predicted stroke. Sensitivity of hemianopia or aphasia for SMs was 52.9%, with specificity of 84.1%, positive predictive value of 78.3%, and negative predictive value of 62.4%.

CONCLUSIONS

Hemianopia and/or aphasia with normal MCTI suggest SMs. Diffusion-weighted MRI might be discussed before rt-PA administration in patients with such a clinical pattern.

Penumbra and re-canalization acute computed tomography in ischemic stroke evaluation: PRACTISE study protocol

Rationale Multimodal imaging, including computed tomography angiography and computed tomography perfusion imaging, yields additional information on intracranial vessels and brain perfusion and can differentiate between ischemic core and penumbra which may affect patient selection for intravenous thrombolysis. Hypothesis The use of multimodal imaging will increase the number of patients receiving intravenous thrombolysis and lead to better treatment outcomes. Sample size 400 patients. Methods and design PRACTISE is a prospective, multicenter, randomized, controlled trial in which patients presenting within 4.5 h of symptom onset are randomized to either the current evidence-based imaging (NCCT alone) or additional multimodal computed tomography imaging (NCCT + computed tomography angiography + computed tomography perfusion). Clinical decisions on intravenous recombinant tissue plasminogen activator are documented. Total imaging time in both arms and time to initiation of treatment delivery in those treated with intravenous recombinant tissue plasminogen activator, is recorded. Follow-up will include brain imaging at 24 h to document infarct size, the presence of edema and the presence of intra-cerebral hemorrhage. Clinical evaluations include NIHSS score at baseline, 24 h and day 7 ± 2, and mRS at day 90 to define functional outcomes. Study outcomes The primary outcome is the proportion of patients receiving intravenous recombinant tissue plasminogen activator. Secondary end-points evaluate times to decision-making, comparison of different image processing software and clinical outcomes at three months. Discussion Multimodal computed tomography is a widely available tool for patient selection for revascularization therapy, but it is currently unknown whether the use of additional imaging in all stroke patients is beneficial. The study opened for recruitment in March 2015 and will provide data on the value of multimodal imaging in treatment decisions for acute stroke.

Effects of increasing IV tPA-treated stroke mimic rates at CT-based centers on clinical outcomes

OBJECTIVE

To determine to what degree stroke mimics skew clinical outcomes and the potential effects of incorrect stroke diagnosis.

METHODS

This retrospective analysis of data from 2005 to 2014 included IV tissue plasminogen activator (tPA)-treated adults with clinical suspicion for acute ischemic stroke who were transferred or admitted directly to our 2 hub hospitals. Primary outcome measures compared CT-based spoke hospitals' and MRI-based hub hospitals' mimic rates, hemorrhagic transformation, follow-up modified Rankin Scale (mRS), and discharge disposition. Secondary outcomes were compared over time.

RESULTS

Of the 725 thrombolysis-treated patients, 29% were at spoke hospitals and 71% at hubs. Spoke hospital patients differed from hubs by age (mean 62 ± 15 vs 72 ± 15 years, p < 0.0001), risk factors (atrial fibrillation, 17% vs 32%, p < 0.0001; alcohol consumption, 9% vs 4%, p = 0.007; smoking, 23% vs 13%, p = 0.001), and mimics (16% vs 0.6%, p < 0.0001). Inclusion of mimics resulted in better outcomes for spokes vs hubs by mRS ≤1 (40% vs 27%, p = 0.002), parenchymal hematoma type 2 (3% vs 7%, p = 0.037), and discharge home (47% vs 37%, p = 0.01). Excluding mimics, there were no significant differences. Comparing epochs, spoke stroke mimic rate doubled (9%-20%, p = 0.03); hub rate was unchanged (0%-1%, p = 0.175).

CONCLUSIONS

Thrombolysis of stroke mimics is increasing at our CT-based spoke hospitals and not at our MRI-based hub hospitals. Caution should be used in interpreting clinical outcomes based on large stroke databases when stroke diagnosis at discharge is unclear. Inadvertent reporting of treated stroke mimics as strokes will artificially elevate overall favorable clinical outcomes with additional downstream costs to patients and the health care system.

Description of stroke mimics after complete neurovascular assessment

INTRODUCTION

A considerable percentage of events initially diagnosed as ischaemic stroke have non-cerebrovascular causes; these are called stroke mimics (SM). Currently available evidence about these events is heterogeneous and comes from studies with small samples.

OBJECTIVE

The purpose of our study is to identify conditions that may present as SM, define their epidemiological and clinical characteristics, and determine the percentage of cases of SM treated with intravenous fibrinolysis.

METHODS

Prospective study including all patients admitted to a tertiary university hospital between June 2005 and April 2015 with a diagnosis of acute stroke. We analysed demographic data, cardiovascular risk factors, time from code stroke activation to admission, stroke severity (NIHSS), final destination after discharge, degree of disability (mRS), and treatment. We compared SM and ischaemic strokes. We ruled out patients with intracranial haemorrhage, subarachnoid haemorrhage, or other causes of SM that may be detected on the baseline CT scan.

RESULTS

Four hundred four of the 4,570 included patients (8.8%) were found to have SM. Patients with SM were younger (70.3 vs. 74, P<.0001), less likely to exhibit cardiovascular risk factors and atrial fibrillation (13 vs. 34%, P<.0001), scored lower on the NIHSS at baseline (2 vs. 4, P<.0001), and included fewer cases of aphasia (9.4 vs. 19.6%, P<.02) and dysphagia (1.2 vs. 17%, P<.0001) than patients with stroke. SM caused fewer code stroke activations (28 vs. 40%, P<.0001). Patients with SM required shorter hospital stays (4.9 vs. 7.8 days, P<.0001), were less frequently admitted to the stroke unit (47 vs. 60%, P<.0001) and more frequently discharged home (95 vs. 62%, P<.0001), and had better outcomes (mRS scores 0-2; 76 vs. 54%, P<.0001). Intravenous fibrinolysis was administered to 4.7% of these patients. Epileptic seizures were the most frequent cause of SM (26%).

CONCLUSIONS

In our sample, 8.8% of all diagnoses of ischaemic stroke were SM. These events have different demographic, clinical, and prognostic characteristics; epilepsy is the most common aetiology. Despite receiving specialised emergency care, 19 patients with SM (4.7%) were treated with intravenous fibrinolysis.

Clinical Mimics: An Emergency Medicine-Focused Review of Stroke Mimics

BACKGROUND

Stroke is a leading cause of death and disability and most commonly presents with focal neurologic deficit within a specific vascular distribution. Several other conditions may present in a similar manner.

OBJECTIVES

This review provides emergency providers with an understanding of stroke mimics, use of thrombolytics in these mimics, and keys to differentiate true stroke from mimic.

DISCUSSION

Stroke has significant morbidity and mortality, and the American Heart Association emphasizes rapid recognition and aggressive treatment for patients with possible stroke-like symptoms, including thrombolytics. However, many conditions mimic the presentation of stroke, with up to a 31% rate of misdiagnosis, leading to potentially harmful treatment. Stroke mimics are conditions that present with stroke-like symptoms, including seizures, headaches, metabolic, infection, space-occupying lesion, neurodegenerative disorder, peripheral neuropathy, syncope, vascular disorder, and functional disorder. Factors of history and physical examination supporting stroke vs. mimic are discussed, though any sudden-onset, objective, focal neurologic deficit in a patient should be assumed acute stroke until proven otherwise. Head computed tomography noncontrast is the first-line imaging modality. Magnetic resonance imaging is the most sensitive and specific imaging modality. Neurology consultation is recommended in the majority of patients. If stroke is suspected after evaluation, shared decision-making for further management and consideration of thrombolytics is recommended.

CONCLUSIONS

Stroke mimics present a conundrum for emergency providers. A new focal neurologic deficit warrants rapid evaluation for stroke with neuroimaging and neurology consultation. Several mimics found on assessment may resolve with treatment.

How a CT-Direct Protocol at an American Comprehensive Stroke Center Led to Door-to-Needle Times Less Than 30 Minutes

BACKGROUND AND PURPOSE

The safety and efficacy of intravenous tissue plasminogen activator (IV tPA) following acute ischemic stroke (AIS) is dependent on its timely administration. In 2014, our Comprehensive Stroke Center designed and implemented a computed tomography-Direct protocol to streamline the evaluation process of suspected patients with AIS, with the aim of reducing door-to-needle (DTN) times. The objectives of our study were to describe the protocol development and implementation process, and to compare DTN times and symptomatic intracranial hemorrhage (sICH) rates before and after protocol implementation.

METHODS

Data were prospectively collected for patients with AIS receiving IV tPA between January 1, 2010, and May 31, 2015. The DTN times, examined as median times and time treatment windows, and sICH rates were compared pre- and postimplementation.

RESULTS

Two hundred ninety-five patients were included in the study. After protocol implementation, median DTN times were significantly reduced (38 vs 28 minutes; P < .001). The distribution of patients treated in the three time treatment windows described below changed significantly, with an increase in patients with DTN times of 30 minutes or less, and a decrease in patients with DTN times 31 to 60 minutes and over 60 minutes (P < .001). There were two cases of sICH prior to implementation and one sICH case postimplementation.

CONCLUSIONS

The implementation of a protocol that streamlined the processing of suspected patients with AIS significantly reduced DTN time without negatively impacting patient safety.

FABS

Background and Purpose—

A large number of patients with symptoms of acute cerebral ischemia are stroke mimics (SMs). In this study, we sought to develop a scoring system (FABS) for screening and stratifying SM from acute cerebral ischemia and to identify patients who may require magnetic resonance imaging to confirm or refute a diagnosis of stroke in the emergency setting.

Methods—

We designed a scoring system: FABS (6 variables with 1 point for each variable present): absence of Facial droop, negative history of Atrial fibrillation, Age <50 years, systolic Blood pressure <150 mm Hg at presentation, history of Seizures, and isolated Sensory symptoms without weakness at presentation. We evaluated consecutive patients with symptoms of acute cerebral ischemia and a negative head computed tomography for any acute finding within 4.5 hours after symptom onset in 2 tertiary care stroke centers for validation of FABS.

Results—

A total of 784 patients (41% SMs) were evaluated. Receiver operating characteristic curve (C statistic, 0.95; 95% confidence interval [CI], 0.93–0.98) indicated that FABS≥3 could identify patients with SM with 90% sensitivity (95% CI, 86%–93%) and 91% specificity (95% CI, 88%–93%). The negative predictive value and positive predictive value were 93% (95% CI, 90%–95%) and 87% (95% CI, 83%–91%), respectively.

Conclusions—

FABS seems to be reliable in stratifying SM from acute cerebral ischemia cases among patients in whom the head computed tomography was negative for any acute findings. It can help clinicians consider advanced imaging for further diagnosis.