Characteristics and predictors of stroke mimics in young patients in the norwegian tenecteplase stroke trial (NOR-TEST).

BACKGROUND: Several studies have shown that stroke mimics occur more often among young patients. Our aims were to identify the common mimics in young patients under the age of 60 years who received thrombolysis, to analyze the risk of hemorrhage after treatment with thrombolysis, and to identify risk factors and clinical parameters that might identify mimics in this group. METHODS: Norwegian Tenecteplase Stroke Trial was a phase-3 trial investigating safety and efficacy of tenecteplase vs. alteplase in patients with acute ischemic stroke. Patients diagnosed with either acute cerebral ischemia or transient ischemic attack were categorized as stroke group, and patients with any diagnosis other than ischemic stroke or transient ischemic attack as mimics group. Patients were grouped post-hoc into young (< 60 years) and old (≥ 60 years). Logistic regression analyses were performed with mimics vs. stroke as dependent variable to identify predictors of mimics. RESULTS: Of the 1091 patients included in the trial, 211 patients (19.3%) were under the age of 60 years. Out of the 1091 patients, 434 (39.8%) were female, median age 77 years (18-99 years), and median NIHSS was 4. Sixty-nine patients (32.7%) out of the 211 patients under the age of 60 were diagnosed as mimic. Mimics were significantly more frequent among the young (OR = 3.3, 32.7% vs. 12.8%, p = < 0.001). The most frequent mimics diagnoses among patients under 60 years of age were migraine (11.8%), no definite diagnosis (11.4%) and peripheral vertigo (3.3%). Mimics were independently associated with age < 50 years (OR = 4.97, p = < 0.001), not currently working/studying (OR = 3.38, p = 0.002) and not having aphasia on admission (OR = 2.95, p = 0.025). None of the mimics under the age of 60 years had symptomatic or asymptomatic intracerebral hemorrhage as a complication to thrombolysis. CONCLUSION: We found significantly more mimics in the young, of which migraine was the most predominant diagnosis. Thrombolysis with alteplase or tenecteplase did not cause ICH in any mimics under 60 years.

Tenecteplase, 0.4 mg/kg, in Moderate and Severe Acute Ischemic Stroke: A Pooled Analysis of NOR-TEST and NOR-TEST 2A.

Background The optimal dose of tenecteplase in acute ischemic stroke remains to be defined. We present a pooled analysis of the 2 NOR-TESTs (Norwegian Tenecteplase Stroke Trials) exploring the efficacy and safety of tenecteplase, 0.4 mg/kg. Methods and Results We retrospectively reviewed 2 PROBE (Prospective Randomized Open, Blinded End-point) trials, NOR-TEST and NOR-TEST 2A. Patients were randomized to either tenecteplase, 0.4 mg/kg, or alteplase, 0.9 mg/kg. The primary end point was favorable functional outcome at 3 months (modified Rankin Scale score, 0-1) or return to baseline if prestroke modified Rankin Scale score was 2. Secondary end points included favorable functional and clinical outcome and safety data. The pooled analysis includes patients with National Institutes of Health Stroke Scale score ≥6 from both trials and an additional post hoc analysis of patients with National Institutes of Health Stroke Scale score ≤5 from NOR-TEST. The per-protocol analysis contains 483 patients, of whom 235 were assigned to tenecteplase and 248 were assigned to alteplase. In per-protocol analysis, functional outcome was better in the alteplase arm with cutoff modified Rankin Scale score of 2 (odds ratio [OR], 0.52 [95% CI, 0.33-0.80]; P=0.003) and expressed by ordinal shift analysis (OR, 1.64 [95% CI, 1.17-2.28]; P=0.004). Mortality at 3 months was higher in the tenecteplase arm (OR, 2.48 [95% CI, 1.20-5.10]; P=0.01). Mortality and intracranial hemorrhage rates were higher in the severe stroke group randomized to tenecteplase, whereas these rates were similar for alteplase and tenecteplase in moderate and mild stroke. Conclusions Tenecteplase, 0.4 mg/kg, is unsafe in moderate and severe stroke, and the risk of death and intracranial hemorrhage probably increases with stroke severity. A lower tenecteplase dose should be tested in future trials. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01949948, NCT03854500.

Endovascular Treatment of Dural Arteriovenous Fistulas in a Medium-Sized Scandinavian Neurovascular Center.

BACKGROUND: Endovascular treatment is the primary treatment modality for dural arteriovenous fistulas (DAVFs). We performed a retrospective analysis of DAVFs treated in our hospital to determine if high-quality endovascular treatment can be provided in a medium-volume vascular center. METHODS: From 2007 to 2021, 69 DAVF treatments were undertaken in our hospital. Of these DAVFs, 55 were endovascular, 11 were open surgical procedures, and 3 were Gamma Knife treatments. Of the endovascular treatments, 10 (18.2%) were in ruptured DAVFs. The most common location of endovascularly treated DAVFs was at the transverse/sigmoid sinus (32.7%) and at the cavernous sinus (25.5%). Of the endovascularly treated DAVFs, 38.2% were low-grade fistulas (Cognard I/IIa), whereas 61.8% were high-grade fistulas (Cognard ≥IIb). 58.2% of fistulas were treated transarterially. DAVFs located in the cavernous sinus were treated using coils alone, whereas most other DAVFs were treated with liquid embolics alone or in combination with coils. RESULTS: Complete or near-complete cure was achieved in 74.5% of treatments, whereas 18.2% of treatments resulted in downgrading of the fistula. Twelve patients were retreated once (9 endovascularly) and 1 patient was retreated twice. After retreatment, complete or near-complete cure was achieved in 86.4% of patients. 72.7% of treatments were performed without any remnant or retreatment. There were no procedure-related deaths. One patient experienced a complication resulting in permanent neurologic deficits. Seven other complications (12.7%) were recorded, all asymptomatic or causing only temporary symptoms. CONCLUSIONS: Based on our findings, we conclude that high-quality treatment of DAVFs can be provided in a medium-volume vascular center.

Comparison of diffusion weighted imaging b0 with T2*-weighted gradient echo or susceptibility weighted imaging for intracranial hemorrhage detection after reperfusion therapy for ischemic stroke.

PURPOSE: Diffusion-weighted imaging (DWI) b0 may be able to substitute T2*-weighted gradient echo (GRE) or susceptibility-weighted imaging (SWI) in case of comparable detection of intracranial hemorrhage (ICH), thereby reducing MRI examination time. We evaluated the diagnostic accuracy of DWI b0 compared to T2*GRE or SWI for detection of ICH after reperfusion therapy for ischemic stroke. METHODS: We pooled 300 follow-up MRI scans acquired within 1 week after reperfusion therapy. Six neuroradiologists each rated DWI images (b0 and b1000; b0 as index test) of 100 patients and, after a minimum of 4 weeks, T2*GRE or SWI images (reference standard) paired with DWI images of the same patients. Readers assessed the presence of ICH (yes/no) and type of ICH according to the Heidelberg Bleeding Classification. We determined the sensitivity and specificity of DWI b0 for detection of any ICH, and the sensitivity for detection of hemorrhagic infarction (HI1 & HI2) and parenchymal hematoma (PH1 & PH2). RESULTS: We analyzed 277 scans of ischemic stroke patients with complete image series and sufficient image quality (median age 65 years [interquartile range, 54-75], 158 [57%] men). For detection of any ICH on DWI b0, the sensitivity was 62% (95% CI: 50-76) and specificity 96% (95% CI: 93-99). The sensitivity of DWI b0 was 52% (95% CI: 28-68) for detection of hemorrhagic infarction and 84% (95% CI: 70-92) for parenchymal hematoma. CONCLUSION: DWI b0 is inferior for detection of ICH compared to T2*GRE/SWI, especially for smaller and more subtle hemorrhages. Follow-up MRI protocols should include T2*GRE/SWI for detection of ICH after reperfusion therapy.

Interobserver Agreement on Intracranial Hemorrhage on Magnetic Resonance Imaging in Patients With Ischemic Stroke.

BACKGROUND: The Heidelberg Bleeding Classification, developed for computed tomography, is also frequently used to classify intracranial hemorrhage (ICH) on magnetic resonance imaging. Additionally, the presence of any ICH is frequently used as (safety) outcome measure in clinical stroke trials that evaluate acute interventions. We assessed the interobserver agreement on the presence of any ICH and the type of ICH according to the Heidelberg Bleeding Classification on magnetic resonance imaging in patients treated with reperfusion therapy. METHODS: We used 300 magnetic resonance imaging scans including susceptibility-weighted imaging or T2*-weighted gradient echo imaging of ischemic stroke patients within 1 week after reperfusion therapy. Six observers, blinded to clinical characteristics except for suspected location of the infarction, independently rated ICH according to the Heidelberg Bleeding Classification in random pairs. Percent agreement and Cohen's kappa (κ) were estimated for the presence of any ICH (yes/no), and for agreement on the Heidelberg Bleeding Classification class 1 and 2. For the Heidelberg Bleeding Classification class 1 and 2, weighted κ was estimated to take the degree of disagreement into account. RESULTS: In 297 of 300 scans, the quality of scans was sufficient to score ICH. Observers agreed on the presence or absence of any ICH in 264 of 297 scans (88.9%; κ 0.78 [95% CI, 0.71-0.85]). There was agreement on the Heidelberg Bleeding Classification class 1 and 2 and no ICH in class 1 and 2 in 226 of 297 scans (76.1%; κ 0.63 [95% CI, 0.56-0.69]; weighted κ 0.90 [95% CI, 0.87-0.93]). CONCLUSIONS: The presence of any ICH can be reliably scored on magnetic resonance imaging and can, therefore, be used as (safety) outcome measure in clinical stroke trials that evaluate acute interventions. Agreement of ICH types according to the Heidelberg Bleeding Classification is substantial and disagreements are small.

Sex differences in the Norwegian Tenecteplase Trial (NOR-TEST).

BACKGROUND AND PURPOSE: Sex differences in acute ischemic stroke is of increasing interest in the era of precision medicine. We aimed to explore sex disparities in baseline characteristics, management and outcomes in patients treated with intravenous thrombolysis included in the Norwegian Tenecteplase trial (NOR-TEST). METHODS: NOR-TEST was an open-label, randomized, blinded endpoint trial, performed from 2012 to 2016, comparing treatment with tenecteplase to treatment with alteplase within 4.5 h after acute ischemic stroke symptom onset. Sex differences at baseline, treatment and outcomes were compared using multivariable logistic regression models. Heterogeneity in treatment was evaluated by including an interaction term in the model. RESULTS: Of 1100 patients enrolled, 40% were women, and in patients aged >80 years, the proportion of women was greater than men (19% vs. 14%; p = 0.02). Women had a lower burden of cardiovascular risk factors, such as diabetes mellitus (11% vs. 15%; p = 0.05) and a higher mean high-density lipoprotein cholesterol level (1.7 ± 0.6 mmol/L vs. 1.3 ± 0.4 mmol/L; p < 0.001), and a higher proportion of women had never smoked (45% vs. 33%; p < 0.001) compared with men. While there was no sex difference in time from onset of symptoms to admission, door to needle time or in-hospital workup, women were admitted with more severe stroke (National Institutes of Health Stroke Scale [NIHSS] score 6.2 ± 5.6 vs. 5.3 ± 5.1; p = 0.01). Stroke mimic diagnosis was more common in women (21% vs. 15%; p = 0.01). There were no significant sex differences in clinical outcome, measured by the NIHSS, the modified Rankin Scale, intracranial hemorrhage and mortality. CONCLUSION: Women were underrepresented in number in NOR-TEST. The included women had a lower cardiovascular risk factor burden and more severe strokes.

The Course of Carotid Plaque Vulnerability Assessed by Advanced Neurosonology.

Background: Carotid artery atherosclerosis is a major risk factor for ischemic stroke. This risk is related to plaque vulnerability and is characterized by plaque morphology, intraplaque neovascularization, and cerebral microembolization. Advanced neurosonology can identify vulnerable plaques and aid in preventing subsequent stroke. We aimed to assess the time course of cerebral microembolization and intraplaque neovascularization during 6 months of follow-up and to explore the utility of advanced neurosonology in patients with acute cerebral ischemia. Methods: Fifteen patients with acute cerebral ischemia and carotid artery plaques underwent comprehensive extra- and intracranial ultrasound examinations, including microemboli detection and contrast-enhanced ultrasound. The examinations were repeated after 3 and 6 months. Results: We examined 28 plaques in 15 patients. The ultrasonographic features of plaque vulnerability were frequent in symptomatic and asymptomatic plaques. There were no significant differences in stenosis degree, plaque composition, plaque surface, neovascularization, or cerebral microembolization between symptomatic and asymptomatic plaques, but symptomatic plaques had a higher number of vulnerable features. None of the patients had recurrent clinical stroke or transient ischemic attack during the follow-up period. We observed a decrease in cerebral microembolization at 6 months, but no significant change in intraplaque neovascularization. Conclusions: In patients with acute cerebral ischemia and carotid artery plaques, cerebral microembolization decreased during 6 months of follow-up, indicating plaque stabilization. Clinical Trial Registration:ClinicalTrial.gov, identifier NCT02759653.

Clinical manifestation of acute cerebral infarcts in multiple arterial territories.

OBJECTIVES: We aimed to assess frequencies and radiological aspects of single- and multiterritory clinical manifestation among patients with acute cerebral infarcts in multiple arterial territories (MACI). MATERIALS & METHODS: We retrospectively reviewed admission records and diffusion-weighted magnetic resonance imaging of patients with MACI admitted to our stroke unit between 2006 and 2017. MACI was defined as acute cerebral ischemic lesions in at least two out of three arterial cerebral territories, that is, the left anterior, right anterior and the bilateral posterior territory. Patients with single- and multiterritory clinical manifestation were then compared for topographical distribution of the ischemic lesions, the number of ischemic lesions, and The Oxfordshire Community Stroke Project classification. RESULTS: Out of 311 patients with MACI, 222 (71.4%) presented with single-territory clinical manifestation. Involvement of the left hemisphere (OR = 0.37, 95% CI 0.16-0.82), less than five ischemic lesions (OR = 0.58, 95% CI 0.35-0.97), and partial anterior circulation infarct clinical stroke syndrome (OR = 0.57, 95% CI 0.34-0.97) were associated with single-territory clinical manifestation. Involvement of all three territories (OR = 2.58, 95% = 1.48-4.50), more than 10 ischemic lesions (OR = 2.30, 95% CI 1.32-4.01) and total anterior circulation infarct clinical stroke syndrome (OR = 3.31, 95% CI 1.39-7.86) were associated with multiterritory clinical manifestation. CONCLUSION: Most patients with MACI present with single-territory clinical manifestation on admission. Diffusion-weighted magnetic resonance imaging is therefore necessary for a definite diagnosis.

Dyslipidemia and rupture risk of intracranial aneurysms-a systematic review.

Dyslipidemia is a well-established risk factor for coronary artery disease. However, the effect on cerebral artery disease, and more specifically the rupture risk of intracranial aneurysms, is unclear and has not yet been reviewed. We therefore performed a systematic review to investigate associations between different types of dyslipidemia and incidence of aneurysmal subarachnoid hemorrhage (aSAH). We used the MEDLINE, Embase, and Web of Science databases to identify clinical trials that compared the rupture risk among SAH patients with or without dyslipidemia. The risk of bias in each included study was evaluated using the Critical Appraisal Skills Program (CASP). Of 149 unique citations from the initial literature search, five clinical trials with a case-control design met our eligibility criteria. These studies compared aSAH patients to patients with unruptured aneurysms and found an overall inverse relationship between hypercholesterolemia and rupture risk of intracranial aneurysms. The quality assessment classified all included studies as high risk of bias. The evidence indicates that hypercholesterolemia is associated with a reduced rupture risk of intracranial aneurysms. However, it is not clear whether this relation is due to the dyslipidemic condition itself or the use of antihyperlipidemic medication.

Tenecteplase versus alteplase after acute ischemic stroke at high age.

BACKGROUND: Stroke prevalence is increasing with age. Alteplase is the only agent approved for thrombolytic treatment for patients with ischemic stroke, including patients ≥80 years. In the present study, the aim was to compare efficacy and safety of tenecteplase and alteplase in patients ≥80 years. METHODS: Data from the Norwegian Tenecteplase Stroke Trial, a randomized controlled trial comparing alteplase and tenecteplase, were assessed. RESULTS: Of the 273 patients ≥80 years included, mean age was 85.5 years.In the intention-to-treat analyses, 43.1% receiving tenecteplase and 39.9% receiving alteplase reached excellent functional outcome (modified Rankin Scale score 0-1) after 3 months (odds ratio (OR) 1.14, 95% confidence interval (CI) 0.70-1.85, p=0.59). No significant differences among patients in the two treatment groups regarding frequency of symptomatic intracranial hemorrhage during the first 48 h were identified (11 (8.5%) in the tenecteplase group, 10 (7.0%) in the alteplase group, OR 1.23, 95% CI 0.50-3.00, p 0.65). Death within 3 months occurred in 18 patients (14.3%) in the tenecteplase group and in 21 (15.3%) in the alteplase group (p 0.84). After excluding stroke mimics, the proportion of patients with excellent functional outcome was 44.1% in the tenecteplase group and 34.4% in the alteplase group (OR 1.50 CI 0.90-2.52, p 0.12). CONCLUSION: No differences in the efficacy and safety of tenecteplase versus alteplase in patients ≥80 years were identified. TRIAL REGISTRATION: Clinicaltrials.gov (NCT01949948).

Clinical outcomes and safety profile of Tenecteplase in wake-up stroke.

BACKGROUND: Tenecteplase has probably pharmacological and clinical advantages in the treatment of acute ischemic stroke. There are lacking data about safety and efficacy of tenecteplase in wake-up stroke (WUPS). AIMS: To investigate safety and efficacy of tenecteplase compared to alteplase in WUPS patients included in NOR-TEST. METHODS: WUPS patients in NOR-TEST were included in the study based on DWI-FLAIR mismatch. Included patients randomly assigned (1:1) to receive intravenous tenecteplase 0.4 mg/kg (to a maximum of 40 mg) or alteplase 0.9 mg/kg (to a maximum of 90 mg). Neurological improvement was defined as 1) favorable functional outcome at 90 days modified Rankin Scale (mRS) of 0 or 1 and 2) neurological improvement measured with the National Institutes of Health Stroke Scale (NIHSS) of 4 points within 24 hours as compared to admission NIHSS or NIHSS 0 at 24 hours. RESULTS: Of 1100 patients from 13 stroke centers included in NOR-TEST, 45 were WUPS patients. Of these, 5 patients were stroke mimics and excluded. Of the remaining 40 patients (3.6%), 24 were treated with alteplase (60%). There was no difference in the number of patients achieving a good clinical outcome (mRS 0-1) in either treatment group. Patients treated with tenecteplase showed a better early neurological improvement (87.5% vs 54.2%, P = 0.027). No ICH was detected on MRI/CT 24-28 hours after thrombolysis. CONCLUSIONS: In WUPS patients treated in NOR-TEST, there was no difference in clinical outcomes at 90 days and no ICH events or deaths were observed in either alteplase- or tenecteplase-treated patients. Clinical Trial Registration-URL: https://www.clinicaltrials.gov. Unique identifier: NCT01949948.

Discontinuation of External Ventricular Drainage in Patients with Hydrocephalus Following Aneurysmal Subarachnoid Hemorrhage - a Scandinavian Multi-institutional Survey.

BACKGROUND: Hydrocephalus requiring external ventricular drainage is common following aneurysmal subarachnoid hemorrhage (aSAH). Timing and strategy for the discontinuation of the external ventricular drain (EVD) are, however, controversial as guidelines are based on limited scientific evidence. A recent similar survey showed that guidelines and recommendations are not being followed. We conducted a questionnaire survey regarding the management of EVD treatment in patients with aSAH and investigated current treatment practice, consensus, and adherence to guidelines within the neurosurgical departments in Scandinavia. METHODS: A questionnaire concerning the management of EVD discontinuation in patients with hydrocephalus following aSAH was distributed to all 14 neurosurgical departments in Scandinavia (Norway, Sweden, and Denmark). Neurosurgeons and neurosurgical trainees at all levels were asked to complete the questionnaire individually. A total of 175 completed questionnaires were received between May 2018 and April 2019, resulting in a response rate of 64 %. RESULTS: Eighty-five percent of respondents reported no knowledge of international guidelines regarding EVD discontinuation in patients with hydrocephalus following aSAH. Within every department, respondents disagreed on whether a common discontinuation strategy was followed or not. Seventy-four percent decided upon the EVD discontinuation strategy mainly determined by patients' clinical condition and drainage volume. Forty-five percent considered Glasgow Coma Score (GCS) the most important clinical variable when assessing the timing of EVD discontinuation. There was general agreement towards the initiation of EVD discontinuation 4-7 days after ictus of aSAH in a stable patient with a drainage volume of < 150 ml/day and intracranial pressure (ICP) < 15 mmHg. CONCLUSION: Awareness of and adherence to international guidelines regarding EVD discontinuation in patients with hydrocephalus following aSAH were limited in Scandinavia. Internal consensus at department level was absent. Initiation of the discontinuation process appeared to be case dependent and mainly influenced by the patients' clinical condition and drainage volume. GCS was the clinical variable considered most important when deciding on the initiation of EVD discontinuation.

Persistent Microembolic Signals in the Cerebral Circulation on Transcranial Doppler after Intravenous Sulfur Hexafluoride Microbubble Infusion.

BACKGROUND AND PURPOSE: Microembolic signals (MES) are detectable by transcranial Doppler monitoring and associated with increased risk of first or recurrent ischemic stroke. MES detection can also illuminate stroke etiology and the effect of prophylactic treatment. MES detection cannot accurately distinguish between stroke-related microemboli and ultrasound contrast agents. These agents contain microbubbles and are frequently used in neuro- and cardiovascular diagnostics. We aimed to assess how long after contrast infusion microbubbles are detectable by transcranial Doppler monitoring. METHODS: Ten healthy volunteers received an intravenous infusion of stabilized sulfur hexafluoride microbubbles (SonoVue®) for 30 minutes. The infusion was followed by continuous unilateral Doppler monitoring (TCD-X, Atys Medical, Soucieu-en-Jarrest, France) for 3.5 hours. RESULTS: MES persisted for 12 to 77 minutes (median 40.5 minutes), and the frequency tended to decrease gradually until cessation. CONCLUSIONS: None of the subjects had detectable MES for more than 77 minutes after ultrasound contrast infusion. MES detection with the intent to detect stroke-related microemboli should wait for at least this long after completed infusion.

Impaired cerebrovascular reactivity may predict delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

INTRODUCTION: Delayed cerebral ischemia (DCI) is a major cause of disability and death after aneurysmal subarachnoid hemorrhage. The literature suggests that impaired cerebrovascular reactivity (CVR) may be a predictor for DCI; still no CVR based prediction model has been developed. Increased knowledge about possible predictors of DCI can improve patient management in high-risk patients and allow for shorter hospital stay in low-risk patients. METHOD: CVR was examined in 42 patients with aneurysmal subarachnoid hemorrhage and 37 patients treated for unruptured intracranial aneurysm, using acetazolamide test with transcranial Doppler monitoring of blood flow velocities. Patients were followed for development of DCI, separated into clinical deterioration and radiographic infarction. RESULTS: For all patients, regardless of aneurysm rupture status, CVR was on average 5.5 percentage points lower on the ipsilateral side of aneurysm treatment. Patients with clinical deterioration due to DCI had lower CVR than patients without DCI, and the difference was larger on the contralateral side (33.9% vs. 49.2%). Two prediction models were constructed for clinical deterioration due to DCI. The area under the receiver operating characteristic curve was 0.82 in the model using established predictors, and 0.86 in the model that also included CVR. CONCLUSION: Our findings support the hypothesis that impaired CVR may be an independent predictor of clinical deterioration due to DCI, and may assist in identifying patients at risk after aneurysmal subarachnoid hemorrhage. Ipsilateral CVR reduction occurs in all patients after aneurysm treatment, regardless of DCI development, thus highlighting the need to evaluate ipsi- and contralateral CVR separately.

Short-Term Outcome and In-Hospital Complications After Acute Cerebral Infarcts in Multiple Arterial Territories.

Background and Purpose- Patients with acute cerebral infarcts in multiple arterial territories (MACI) represent a substantial portion of the stroke population. There are no data on short-term outcome and in-hospital complications in patients with MACI. We compared patients with MACI with patients having acute cerebral infarct(s) in a single arterial territory. Methods- We analyzed 3343 patients with diffusion-weighted imaging-confirmed acute cerebral infarcts. MACI was defined as at least 2 acute cerebral ischemic lesions in at least 2 arterial cerebral territories. Patients with MACI were compared with patients with acute cerebral infarct(s) in a single arterial territory for relevant in-hospital complications and short-term outcome, namely National Institutes of Health Stroke Scale and modified Rankin Scale at day 7 after admission or at discharge when earlier. Results- A total of 311 patients (9.3%) met the definition of MACI. Both median National Institutes of Health Stroke Scale (2 [1-7] versus 1 [0-4]) and modified Rankin Scale (3 [1-4] versus 2 [1-3]) were higher in patients with MACI. MACI was independently associated with higher National Institutes of Health Stroke Scale and modified Rankin Scale. Deep venous thrombosis, myocardial infarction, and any complications were more frequent in patients with MACI. Conclusions- In-hospital complications were more frequent in patients with MACI, which may adversely affect short-term clinical and functional outcome. Closer follow-up of patients with MACI during hospitalization may prevent such events and negative progression.

Incidence and Etiologies of Stroke Mimics After Incident Stroke or Transient Ischemic Attack.

Background and Purpose- Stroke mimics (SM) pose a common clinical challenge, but the burden of SM in patients with previous ischemic stroke (IS) or transient ischemic attack is unknown. The objective of this study was to calculate the incidence of SM in IS survivors, compare it with the incidence of recurrent stroke in the same population, and explore the time-dependent patterns of SM etiologies. Methods- This prospective cohort study registered SM events and etiologies among 1872 IS and transient ischemic attack survivors diagnosed with index stroke at Haukeland University Hospital stroke unit from 2007 to 2013 by review of medical records. Cumulative incidences of SM were estimated with a competing risks Cox model and compared with incidence of recurrent stroke in the same population. Results- During 8172 person-years of follow-up, 339 patients had 480 SM events. The cumulative incidence rate of SM during follow-up was 58.7 per 1.000 person-years (95% CI, 53.7-64.2) compared with 34.0 per 1.000 person-years (95% CI, 30.2-38.2) for recurrent stroke in the same time period. The risks of SM and recurrent stroke were highest the first year after index IS or transient ischemic attack. The most frequent SM diagnoses were sequelae of cerebral infarction (19.8%), medical observation, and evaluation for suspected cerebrovascular disease (15.6%) and infections (14.0%). The 2 most frequent and unspecific diagnoses (sequelae of cerebral infarction and medical observation) were clustered in the first months after index stroke. Conclusions- SM after IS or transient ischemic attack are more frequent than recurrent stroke and the risk is especially high in the early period. SMs are multietiological and unspecific diagnoses are most frequent early after index stroke.