Follow-up ASPECTS improves prediction of potentially lethal malignant edema in patients with large middle cerebral artery stroke

BACKGROUND

Recent studies have shown that follow-up head CT is a strong predictor of functional outcomes in patients with middle cerebral artery stroke and mechanical thrombectomy. We sought to determine whether total and/or regional follow-up Alberta Stroke Program Early CT Score (ASPECTSfu) are associated with important clinical outcomes during hospitalization and improve the performance of clinical prediction models of potentially lethal malignant edema (PLME).

METHODS

We conducted a retrospective study of patients at three medical centers in a major North American metropolitan area with baseline and follow-up head CTs after large middle cerebral artery stroke between 2006 and 2022. We used multivariable logistic regression to test the association of total and regional ASPECTSfu with PLME (cerebral edema related death or surgery), adjusting for total baseline ASPECTS, age, sex, admission glucose, tissue plasminogen activator, and mechanical thrombectomy. We compared existing clinical risk models with and without total or regional ASPECTSfu using area under the curve.

RESULTS

In our 560 patient cohort, lower total ASPECTSfu was significantly associated with higher odds of PLME when adjusting for confounders (OR 1.69, 95% CI 1.49 to 2.0), and improved model discrimination compared with existing models and models using baseline ASPECTS. Deep territory involvement (OR 2.46, 95% CI 1.53 to 4.01) and anterior territory involvement (OR 3.23, 95% CI 1.88 to 5.71) were significantly associated with PLME.

CONCLUSIONS

Lower ASPECTSfu and certain locations on regional ASPECTSfu, including deep and anterior areas, were significantly associated with PLME. Including ASPECTSfu information improved discrimination of established edema prediction models and could be used immediately to help facilitate clinical management decisions and prognostication.

Strokes in Patients With Injection Drug Use and Tricuspid Valve Endocarditis - A Case Series

Research Design: In this study, we describe patients from a tertiary care safety-net hospital endocarditis registry with tricuspid valve infective endocarditis (TVIE), and concomitant acute or subacute ischemic stroke predominantly associated with injection drug use (IDU). We retrospectively obtained data pertinent to neurologic examinations, history of injection drug use (IDU), blood cultures, transthoracic/transesophageal echocardiography (TTE/TEE), neuroimaging, and Modified Rankin Scale (mRS) scores at discharge. Only those patients with bacteremia, tricuspid valve vegetations, and neuroimaging consistent with acute to subacute ischemic infarction and microhemorrhages in two cases were included in this series. Results: Of 188 patients in the registry, 66 patients had TVIE and 10 of these were complicated by ischemic stroke. Neurologic symptoms were largely non-specific, eight patients had altered mental status and only 3 had focal deficits. Nine cases were associated with IDU. Two patients had evidence of a patent foramen ovale on echocardiography. Blood cultures grew S. aureus species in 9 of the patients, all associated with IDU. Three patients died during hospitalization. The mRS score at discharge for survivors ranged 0-4. Conclusions: Patients with strokes from TVIE had heterogeneous presentations and putative mechanisms. We noted that robust neuroimaging is lacking for patients with TVIE from IDU and that such patients may benefit from neuroimaging as a screen for strokes to assist peri-operative management. Further inquiry is needed to elucidate stroke mechanisms in these patients.

Global Impact of the COVID-19 Pandemic on Stroke Volumes and Cerebrovascular Events: A 1-Year Follow-up

BACKGROUND AND OBJECTIVES

Declines in stroke admission, IV thrombolysis (IVT), and mechanical thrombectomy volumes were reported during the first wave of the COVID-19 pandemic. There is a paucity of data on the longer-term effect of the pandemic on stroke volumes over the course of a year and through the second wave of the pandemic. We sought to measure the effect of the COVID-19 pandemic on the volumes of stroke admissions, intracranial hemorrhage (ICH), IVT, and mechanical thrombectomy over a 1-year period at the onset of the pandemic (March 1, 2020, to February 28, 2021) compared with the immediately preceding year (March 1, 2019, to February 29, 2020).

METHODS

We conducted a longitudinal retrospective study across 6 continents, 56 countries, and 275 stroke centers. We collected volume data for COVID-19 admissions and 4 stroke metrics: ischemic stroke admissions, ICH admissions, IVT treatments, and mechanical thrombectomy procedures. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases.

RESULTS

There were 148,895 stroke admissions in the 1 year immediately before compared with 138,453 admissions during the 1-year pandemic, representing a 7% decline (95% CI [95% CI 7.1-6.9]; p < 0.0001). ICH volumes declined from 29,585 to 28,156 (4.8% [5.1-4.6]; p < 0.0001) and IVT volume from 24,584 to 23,077 (6.1% [6.4-5.8]; p < 0.0001). Larger declines were observed at high-volume compared with low-volume centers (all p < 0.0001). There was no significant change in mechanical thrombectomy volumes (0.7% [0.6-0.9]; p = 0.49). Stroke was diagnosed in 1.3% [1.31-1.38] of 406,792 COVID-19 hospitalizations. SARS-CoV-2 infection was present in 2.9% ([2.82-2.97], 5,656/195,539) of all stroke hospitalizations.

DISCUSSION

There was a global decline and shift to lower-volume centers of stroke admission volumes, ICH volumes, and IVT volumes during the 1st year of the COVID-19 pandemic compared with the prior year. Mechanical thrombectomy volumes were preserved. These results suggest preservation in the stroke care of higher severity of disease through the first pandemic year.

TRIAL REGISTRATION INFORMATION

This study is registered under NCT04934020.

Risk factors for neurological complications in left-sided infective endocarditis

BACKGROUND AND PURPOSE

Neurological complications following infective endocarditis (IE) directly contribute to long-term morbidity. We examined the risk factors for different neurological complications of left-sided IE.

METHODS

Using a database of consecutive adults admitted to a health system with left-sided IE from 2015 to 2019, the frequency of cerebral infarcts, intraparenchymal hemorrhage, cerebral microbleeds (CMB), mycotic aneurysm, and encephalopathy was determined. Variables with significant differences comparing each neurological complication (p < 0.1) were entered into regression models along with age to determine predictors.

RESULTS

211 patients with mean age 54 (±18) years, and 69 (33%) females were included. Infarcts were found in 118 (56%) patients, intraparenchymal hemorrhage was found in 17 (8%) patients, CMB were found in 58 (27%) patients, mycotic aneurysms were found in 22 (10%) patients, and encephalopathy occurred in 16 (8%) patients. In multivariable models, vegetation size ≥15 mm was associated with a higher risk of infarcts (aOR 2.26, 95% CI (1.12-4.57)), and the presence of a mycotic aneurysm was a risk factor for intraparenchymal hemorrhage (aOR 18.79, 95% CI (3.97-88.97)). Prosthetic valves (aOR 2.89, 95% CI (1.11-7.54)) and Staphylococcus aureus infection (aOR 3.50, 95% CI (1.08-11.36)) were associated with CMB. No risk factors emerged as predictors of encephalopathy.

CONCLUSIONS

Large vegetation size is associated with stroke in patients with IE. Mycotic aneurysms are found at a higher frequency in young patients and are the primary cause of intraparenchymal hemorrhage. CMB may be related to prosthetic valves and Staphylococcus aureus infection.

Screening neuroimaging in neurologically asymptomatic patients with infective endocarditis

BACKGROUND AND PURPOSE

Neurological complications from infective endocarditis (IE) are common and often present with minimal clinical symptoms. In this study, we examine whether screening neuroimaging in asymptomatic patients results in increased detection of neurological complications and leads to improved patient outcomes.

METHODS

Using a database of consecutive adults with IE admitted to a single health system from 2015 to 2019, we selected patients who presented without any neurological symptoms and determined whether these patients underwent screening neuroimaging. The presence of septic emboli, territorial infarcts, intracranial hemorrhage, and mycotic aneurysms was recorded. Variables with significant differences in univariable analyses (p < .1) between those with and without screening neuroimaging were entered into regression models with age and sex to determine predictors of neurological complications and favorable discharge outcomes (modified Rankin score ≤2).

RESULTS

A total of 214 patients were included in the study, of which 154 (72%) received screening neuroimaging. Septic emboli were more common in patients who underwent screening imaging (31% vs. 15%, p = 0.02). In the first multivariate analysis, screening neuroimaging was associated with septic emboli (adjusted odds ratio [aOR] = 2.44, 95% confidence interval [CI]: [1.03-5.75], p = 0.04). In the second multivariate analysis, territorial infarcts (aOR = 0.28, 95% CI: [0.11-0.73], p = .01), but not septic emboli (aOR = 0.71, 95% CI: [0.36-1.43], p = 0.34), were associated with a favorable discharge outcome.

CONCLUSIONS

Screening neuroimaging leads to the detection of more septic emboli in IE, but only territorial infarcts (in contrast to septic emboli) correlate with an unfavorable discharge outcome.

Ischemic Stroke

This concise review of the epidemiology, pathophysiology, evaluation, acute management, and prevention of ischemic stroke targets internists, family practitioners, and emergency physicians who manage patient with stroke.

Diffuse Cerebral Edema After Moyamoya Disease-Related Intracerebral Hemorrhage: A Case Report

Moyamoya disease (MMD) is a rare, progressive occlusive disease characterized by bilateral internal carotid artery hypoplasia that often presents with ischemic stroke and intracerebral hemorrhage (ICH). Although MMD-related ICH is generally managed similarly to spontaneous ICH, we present a case in which standard management strategies may have led to an unprecedented devastating outcome. A 37-year-old female without any previous medical history presented with headache and right-sided weakness. A computed tomography (CT) scan revealed a large left basal ganglia ICH. Vessel imaging revealed diffuse narrowing of the entire anterior circulation with prominent leptomeningeal collaterals consistent with MMD. The patient's systolic blood pressure was kept under 140 mmHg. During the hospitalization, she became hypocarbic while being trialed on pressure support ventilation. Several hours later, she developed fixed and dilated pupils. Repeat CT head showed new diffuse cerebral edema with tonsillar herniation. Despite hyperosmolar therapy, paralytics, pentobarbital, and cerebrospinal fluid diversion, no improvement was noted. Unfortunately, brain MRI revealed multifocal brainstem infarcts with superimposed Duret hemorrhages. Herein, we report diffuse cerebral edema as a complication of MMD-related ICH. We hypothesize that disruptions of delicate cerebral autoregulatory mechanisms led to extensive hypoxic-ischemic injury. In the setting of ICH, aggressive blood pressure management coupled with relative hypocapnia may have likely caused vasoconstriction of poorly compliant arteries leading to worsened cerebral blood flow and ischemia. Therefore, because of its complex pathophysiology, strict adherence to eucapnia should be maintained in MMD-related ICH.

Characteristics and Outcomes of Latinx Patients With COVID-19 in Comparison With Other Ethnic and Racial Groups

BACKGROUND

There is a limited understanding of the impact of coronavirus disease 2019 (COVID-19) on the Latinx population. We hypothesized that Latinx patients would be more likely to be hospitalized and admitted to the intensive care unit (ICU) than White patients.

METHODS

We analyzed all patients with COVID-19 in 12 Massachusetts hospitals between February 1 and April 14, 2020. We examined the association between race, ethnicity, age, reported comorbidities, and hospitalization and ICU admission using multivariable regression.

RESULTS

Of 5190 COVID-19 patients, 29% were hospitalized; 33% required the ICU, and 4.3% died. Forty-six percent of patients were White, 25% Latinx, 14% African American, and 3% Asian American. Ethnicity and race were significantly associated with hospitalization. More Latinx and African American patients in the younger age groups were hospitalized than whites. Latinxs and African Americans disproportionally required the ICU, with 39% of hospitalized Latinx patients requiring the ICU compared with 33% of African Americans, 24% of Asian Americans, and 30% of Whites (P < .007). Within each ethnic and racial group, age and male gender were independently predictive of hospitalization. Previously reported preexisting comorbidities contributed to the need for hospitalization in all racial and ethnic groups (P < .05). However, the observed disparities were less likely related to reported comorbidities, with Latinx and African American patients being admitted at twice the rate of Whites, regardless of such comorbidities.

CONCLUSIONS

Latinx and African American patients with COVID-19 have higher rates of hospitalization and ICU admission than White patients. The etiologies of such disparities are likely multifactorial and cannot be explained only by reported comorbidities.

Fibrinogen Concentrate for the Treatment of Thrombolysis-Associated Hemorrhage in Adult Ischemic Stroke Patients

In patients with ischemic stroke who receive systemic recombinant tissue plasminogen activator (rt-PA), the risk of secondary hemorrhage is 1-7%. Fibrinogen supplementation with cryoprecipitate is recommended in patients with rt-PA-associated symptomatic hemorrhage. We examined whether fibrinogen concentrate can be used safely in this setting. A single-center retrospective case series was performed in patients who received fibrinogen concentrate for post-rt-PA hemorrhage between January-2012 and December-2017. The primary outcome was the incidence of in-hospital thromboembolic events and infusion reactions. Secondary outcomes included incidence of clinically significant ICH expansion within 24-hours and patient serum fibrinogen response to fibrinogen concentrate therapy. Thromboembolic events occurred in 3 (12.5%) of 24 patients included in the analysis. No patients experienced infusion-related reactions. Five of 22 patients with ICH experienced clinically significant hemorrhage expansion. Hypofibrinogenemia was corrected in 87.5%(7/8) of patients with baseline hypofibrinogenemia, with a median increase in serum fibrinogen 166 mg/dL. Median fibrinogen increase in patients without baseline hypofibrinogenemia was 18 mg/dL. Fibrinogen concentrate is a safe potential therapeutic option to restore fibrinogen levels in acute ischemic stroke patients with thrombolysis-associated hemorrhage.

Preserving Access: A Review of Stroke Thrombectomy during the COVID-19 Pandemic

Thrombectomy for large-vessel-occlusion stroke is a highly impactful treatment. The spread of coronavirus 19 (COVID-19) across the United States and the globe impacts access to this crucial intervention through widespread societal and institutional changes. In this document, we review the implications of COVID-19 on the emergency care of large-vessel occlusion stroke, reviewing specific infection-control recommendations, available literature, existing resources, and expert consensus. As a population, patients with large-vessel occlusion stroke face unique challenges during pandemics. These are broad in scope. Responses to these challenges through adaptation of stroke systems of care and with imaging, thrombectomy, and postprocedural care are detailed. Preservation of access to thrombectomy must be prioritized for its public health impact. While the extent of required changes will vary by region, tiered planning for both escalation and de-escalation of measures must be a part of each practice. In addition, preparations described serve as templates in the event of future pandemics.

Trends in Telestroke Care Delivery: A 15-Year Experience of an Academic Hub and Its Network of Spokes

BACKGROUND

Telestroke provides access to vascular neurology expertise for hospitals lacking stroke coverage, and its use has risen rapidly in the past decade. We aim to characterize consultations, spoke behavior, and the relationship between spoke telestroke utilization (number of telestroke consults per year) and spoke alteplase treatment metrics in an academic telestroke network.

METHODS AND RESULTS

We analyzed prospectively collected data on all telestroke consults from 2003 to 2018. Trends in network performance and spoke characteristics were analyzed using generalized estimating equations and Kendall τβ nonparametric tests as appropriate. Unadjusted and adjusted linear regression models determined associations between telestroke utilization and treatment metrics. The network included 2 hubs and 43 spokes with 12 803 consults performed during the study period. Network growth overall was +1.8 spokes per year, and median duration of spoke participation was 7.9 years. The numbers of consults and alteplase-treated patients increased annually, even after adjusting for the number of spokes in the network (P<0.01 for both). Although times from last seen well to spoke emergency department arrival and to consult request increased, door-to-needle time, time from teleconsult request to callback, and time from teleconsult to alteplase administration all decreased (all P<0.01). With time, the network included more spokes without a Primary Stroke Center designation. In adjusted analyses, for every 10 telestroke consults requested by a spoke, the spoke door-to-needle decreased by 1.8 minutes (P=0.02), number of patients treated with alteplase was an additional 1.7 (P<0.01), and the percent of eligible patients treated with alteplase increased by 8% (P=0.03).

CONCLUSIONS

Telestroke network size and utilization increased over time. Increased use of teleconsults was associated with increased and timely use of alteplase. Over time, the delivery of timely emergency care has improved significantly among emergency departments participating in this telestroke network. Replication of these findings in other networks is warranted.

Abstract WP276: Variation in Treatment Times for Patients With LVO - The Massachusetts Statewide Experience

Introduction: Acute ischemic stroke guidelines recommend endovascular therapy (EVT) for select patients with large vessel occlusion (LVO). A committee of stroke care providers from across MA pooled data to evaluate LVO related care and improve stroke systems of care. We sought to determine variation in care and factors associated with timeliness of Door To Start of Revascularization (first pass)(DTR).

Methods: We analyzed 2018 patient-level Get with the Guidelines-Stroke data from 7 of 8 MA EVT-capable centers who provided consent for us to pool the data. Factors affecting DTR times were compared with univariate analysis (Kruskal-Wallis and t-tests as appropriate) and in linear regression models to identify those independently associated with DTR times, adjusted for patient characteristics and clustering by hospital. Variables included age, stroke severity, arrival on (M-F 7a-7p) vs. off hours, mode of arrival (EMS from scene vs interhospital transfer), and hospital EVT volume.

Results: Median DTR for 317 patients from 7 centers was 89 (IQR 59-128) min. Site-specific median DTR times varied from 58 (IQR 30-93) to 137.5 (IQR 80.5-171.5) min. In univariate comparisons, median DTR times were shorter after interhospital transfer than EMS from scene (74 (IQR 45-108) vs. 114 (IQR 89-151) min, p<0.001). After controlling for other characteristics, stroke severity, mode of arrival, and off-hours arrival were significantly associated with DTR times, but hospital EVT volume was not (Table).

Conclusion: Analysis of GWTG-Stroke data for MA demonstrates variability in hospital-level DTR times, with LVO patients presenting during off hours/holidays experiencing delays in DTR. Reassuringly, patients with more severe strokes were more likely to have shorter DTR times. While hospital EVT volume was not significant, this may be due to small sample size. This variability in performance suggests opportunities for improvement in the MA stroke systems of care.

Microemboli After Successful Thrombectomy Do Not Affect Outcome but Predict New Embolic Events

Background and Purpose- We aimed to determine if microemboli after endovascular thrombectomy correlate with unfavorable outcomes despite successful recanalization. Methods- This is a prospective multicenter study of consecutive patients with ischemic stroke and occlusion of anterior circulation vessels (terminal internal carotid or main trunk of the middle cerebral artery/first-order branch of the main trunk of the middle cerebral artery segments of middle cerebral artery) after successful thrombectomy (modified Treatment In Cerebral Ischemia grades 2b-3). Microembolic signals (MES) were assessed by 30 minutes of transcranial Doppler monitoring within 72 hours of the last-seen-well time. Major outcomes included modified Rankin Scale at 90 days and infarct volume on head computed tomography at 24 hours. We also assessed early outcomes based on National Institutes of Health Stroke Scale variation and recurrence of stroke, transient ischemic attack, or systemic embolism within 90 days. Results- Among 111 patients, MES were detected in 43 (39%), with a median rate of 4 counts/h (interquartile range 2-12). The occurrence of MES was not associated with a significant difference in modified Rankin Scale (ordinal shift analysis, adjusted odds ratio, 1.06 [95% CI, 0.48-2.34] P=0.85) nor in functional independence (modified Rankin Scale, 0-2: adjusted odds ratio, 0.52 [95% CI, 0.19-1.39] P=0.19). Patients with and without MES had similar infarct volumes (adjusted beta, 11.2 [95% CI, -46.6 to +22.9] P=0.51) on 24-hour computed tomography. MES did predict new embolic events (adjusted Cox hazard ratio, 6.78 [95% CI, 1.63-27.8] P=0.01). Conclusions- MES detected by transcranial Doppler following endovascular treatment of anterior circulation occlusions do not predict clinical or radiological outcome. However, such emboli are an independent marker of recurrent embolic events within 90 days.

Social Network Mapping and Functional Recovery Within 6 Months of Ischemic Stroke

Objective. Stroke recovery is a multidimensional process influenced by biological and psychosocial factors. To understand the latter, we mapped the social networks of stroke patients, analyzing their changes and effects on physical function at 3 and 6 months after stroke. Methods. We used a quantitative social network assessment tool to map the structure and health habits embedded in patients' personal social networks. The physical function outcome was determined using the National Institutes of Health (NIH) Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Scale (0-100, mean 50 for US general population). We used mixed-effects models to assess changes in social network metrics. We used multivariable models to test the association between social networks and physical function, independent of demographics, socioeconomic status, clinical characteristics, comorbidities, cognition, and depression. Results. The cohort consisted of 172 patients, with mostly mild motor-predominant stroke (median NIH Stroke Scale of 2) with retention of 149 at 3 months and 139 at 6 months. An average patient's network over 6 months contracted by 1.25 people and became denser and family oriented. Network composition also became healthier with pruning of ties with people who smoked or did not exercise. The baseline network size, and not density or health habits in the network, was independently associated with 3- and 6-month physical function PROMIS scores. Patients embedded in small kin-based networks reported more negative social interactions. Conclusions. Despite social networks becoming smaller and close-knit after stroke, they also become healthier. Larger baseline social networks are independently associated with better patient-reported physical function after stroke.

Stroke in Pregnancy: An Update

Pregnancy confers a substantially increased risk of stroke in women. The period of highest risk of stroke is the peripartum/postpartum phase, coinciding with the highest risk for hypertensive disorders of pregnancy and peak gestational hypercoagulability. Hemorrhagic stroke is the most common type of obstetric stroke. Hypertensive disorders of pregnancy are important contributors to obstetric stroke and predispose women to premature cardiovascular disease. The rate of stroke associated with hypertensive disorders of pregnancy has increased in the United States. Other conditions associated with obstetric stroke include posterior reversible encephalopathy, reversible cerebral vasoconstriction syndrome, and cerebral venous sinus thrombosis.

Early molecular oxidative stress biomarkers of ischemic penumbra in acute stroke

OBJECTIVES

To assess whether plasma biomarkers of oxidative stress predict diffusion-perfusion mismatch in patients with acute ischemic stroke (AIS).

METHODS

We measured plasma levels of oxidative stress biomarkers such as F2-isoprostanes (F2-isoPs), total and perchloric acid Oxygen Radical Absorbance Capacity (ORAC_TOT and ORAC_PCA), urinary levels of 8-oxo-7,8-dihydro-2'-deoxyguoanosine, and inflammatory and tissue-damage biomarkers (high-sensitivity C-reactive protein, matrix metalloproteinase-2 and -9) in a prospective study of patients with AIS presenting within 9 hours of symptom onset. Diffusion-weighted (DWI) and perfusion-weighted (PWI) MRI sequences were analyzed with a semiautomated volumetric method. Mismatch was defined as baseline mean transit time volume minus DWI volume. A percent mismatch cutoff of >20% was considered clinically significant. A stricter definition of mismatch was also used. Mismatch salvage was the region free of overlap by final infarction.

RESULTS

Mismatch >20% was present in 153 of 216 (70.8%) patients (mean [±SD] age 69.2 ± 14.3 years, 41.2% women). Patients with mismatch >20% were more likely to have higher baseline plasma levels of ORAC_PCA (p = 0.020) and F2-isoPs (p = 0.145). Multivariate binary logistic regression demonstrated that lnF2-isoP (odds ratio [OR] 2.44, 95% confidence interval [CI] 1.19-4.98, p = 0.014) and lnORAC_PCA (OR 4.18, 95% CI 1.41-12.41, p = 0.010) were independent predictors of >20% PWI-DWI mismatch and the stricter mismatch definition, respectively. lnORAC_TOT significantly predicted mismatch salvage volume (>20% mismatch p = 0.010, stricter mismatch definition p = 0.003).

CONCLUSIONS

Elevated hyperacute plasma levels of F2-isoP and ORAC are associated with radiographic evidence of mismatch and mismatch salvage in patients with AIS. If validated, these findings may add to our understanding of the role of oxidative stress in cerebral tissue fate during acute ischemia.

Treatment Approaches to Lacunar Stroke

Lacunar strokes are appropriately named for their ability to cavitate and form ponds or "little lakes" (Latin: lacune -ae meaning pond or pit is a diminutive form of lacus meaning lake). They account for a substantial proportion of both symptomatic and asymptomatic ischemic strokes. In recent years, there have been several advances in the management of large vessel occlusions. New therapies such as non-vitamin K antagonist oral anticoagulants and left atrial appendage closure have recently been developed to improve stroke prevention in atrial fibrillation; however, the treatment of small vessel disease-related strokes lags frustratingly behind. Since Fisher characterized the lacunar syndromes and associated infarcts in the late 1960s, there have been no therapies specifically targeting lacunar stroke. Unfortunately, many therapeutic agents used for the treatment of ischemic stroke in general offer only a modest benefit in reducing recurrent stroke while adding to the risk of intracerebral hemorrhage and systemic bleeding. Escalation of antithrombotic treatments beyond standard single antiplatelet agents has not been effective in long-term lacunar stroke prevention efforts, unequivocally increasing intracerebral hemorrhage risk without providing a significant benefit. In this review, we critically review the available treatments for lacunar stroke based on evidence from clinical trials. For several of the major drugs, we summarize the adverse effects in the context of this unique patient population. We also discuss the role of neuroprotective therapies and neural repair strategies as they may relate to recovery from lacunar stroke.

Oxidative Stress Biomarkers of Brain Damage: Hyperacute Plasma F2-Isoprostane Predicts Infarct Growth in Stroke

BACKGROUND AND PURPOSE

Oxidative stress is an early response to cerebral ischemia and is likely to play an important role in the pathogenesis of cerebral ischemic injury. We sought to evaluate whether hyperacute plasma concentrations of biomarkers of oxidative stress, inflammation, and tissue damage predict infarct growth (IG).

METHODS

We prospectively measured plasma F2-isoprostane (F2-isoP), urinary 8-oxo-7,8-dihydro-2'-deoxyguoanosine, plasma oxygen radical absorbance capacity assay, high sensitivity C reactive protein, and matrix metalloproteinase 2 and 9 in consecutive patients with acute ischemic stroke presenting within 9 hours of symptom onset. Patients with baseline diffusion-weighted magnetic resonance imaging and follow-up diffusion-weighted imaging or computed tomographic scan were included to evaluate the final infarct volume. Baseline diffusion-weighted imaging volume and final infarct volume were analyzed using semiautomated volumetric method. IG volume was defined as the difference between final infarct volume and baseline diffusion-weighted imaging volume.

RESULTS

A total of 220 acute ischemic stroke subjects were included in the final analysis. One hundred seventy of these had IG. Baseline F2-isoP significantly correlated with IG volume (Spearman ρ=0.20; P=0.005) and final infarct volume (Spearman ρ=0.19; P=0.009). In a multivariate binary logistic regression model, baseline F2-isoP emerged as an independent predictor of the occurrence of IG (odds ratio, 2.57; 95% confidence interval, 1.37-4.83; P=0.007). In a multivariate linear regression model, baseline F2-isoP was independently associated with IG volume (B, 0.38; 95% confidence interval, 0.04-0.72; P=0.03).

CONCLUSIONS

Elevated hyperacute plasma F2-isoP concentrations independently predict the occurrence of IG and IG volume in patients with acute ischemic stroke. If validated in future studies, measuring plasma F2-isoP might be helpful in the acute setting to stratify patients with acute ischemic stroke for relative severity of ischemic injury and expected progression.

Abstract TMP37: Social Network Size at Stroke Onset is Associated With 3 and 6-Month Stroke Outcomes

Introduction: Social mechanisms involved in stroke recovery are important and underutilized. For at least three decades, research has shown that social factors such as living alone negatively influence outcomes after stroke. Prior studies relied on social support measures without study of the network social structure. Our study uses higher-resolution social network analysis to examine structure (e.g., size and connectivity) and composition (e.g., proportion kin) in relation to stroke outcomes at 3 and 6 months.

Hypothesis: Social network structural traits, size and connectivity, at stroke onset is related to the Patient Recovery Outcome Measurement Information System (PROMIS) physical function score at 3 and 6 months.

Methods: In a cohort study, 160 patients with a first-time ischemic stroke were enrolled at stroke hospitalization. Social network characteristics were assessed using a bedside survey interview. The PROMIS physical function score was assessed on the phone at 3 and 6 months after stroke. Unadjusted and adjusted analyses were completed using Spearman Correlation and multivariate linear regression.

Results: 144 patients (90%) at 3 months and 120 patients (75%) at 6 months completed the study. The mean age was 62, and NIH stroke scale was 3. Social network size at stroke onset was positively associated with 3- (spearman correlation=0.22, p<0.01) and 6-month (spearman correlation=0.21, p=0.02) PROMIS physical function score. Connectivity measures and the proportion of kin in the network were not associated with the outcome. After control of age, stroke severity, and depression, network size remained strongly associated to physical function at 3 and 6-months, beta=0.74 [0.51,0.97], p<0.01.

Conclusions: Of social network traits, network size at stroke onset is independently associated with physical function after stroke. Small networks are an important risk factor for poor recovery, likely equivalent to traditional risk factors.

Clinical Problem-Solving: Lethargy and Fever in an Immunocompromised Patient

We present the case of a 63-year-old woman with a glioblastoma multiforme on immunosuppressive steroid doses who developed lethargy and fever. We review the differential diagnosis and emphasize the importance of reframing the case when the clinical course differs from expectation. Once the diagnosis is evident, we discuss the incidence and clinical course in different patient populations.

Cerebrovascular Hemodynamics in Women

Sex and gender, as biological and social factors, significantly influence health outcomes. Among the biological factors, sex differences in vascular physiology may be one specific mechanism contributing to the observed differences in clinical presentation, response to treatment, and clinical outcomes in several vascular disorders. This review focuses on the cerebrovascular bed and summarizes the existing literature on sex differences in cerebrovascular hemodynamics to highlight the knowledge deficit that exists in this domain. The available evidence is used to generate mechanistically plausible and testable hypotheses to underscore the unmet need in understanding sex-specific mechanisms as targets for more effective therapeutic and preventive strategies.

Emerging Cases of Powassan Virus Encephalitis in New England: Clinical Presentation, Imaging, and Review of the Literature

BACKGROUND

Powassan virus (POWV) is a rarely diagnosed cause of encephalitis in the United States. In the Northeast, it is transmitted by Ixodes scapularis, the same vector that transmits Lyme disease. The prevalence of POWV among animal hosts and vectors has been increasing. We present 8 cases of POWV encephalitis from Massachusetts and New Hampshire in 2013-2015.

METHODS

We abstracted clinical and epidemiological information for patients with POWV encephalitis diagnosed at 2 hospitals in Massachusetts from 2013 to 2015. We compared their brain imaging with those in published findings from Powassan and other viral encephalitides.

RESULTS

The patients ranged in age from 21 to 82 years, were, for the most part, previously healthy, and presented with syndromes of fever, headache, and altered consciousness. Infections occurred from May to September and were often associated with known tick exposures. In all patients, cerebrospinal fluid analyses showed pleocytosis with elevated protein. In 7 of 8 patients, brain magnetic resonance imaging demonstrated deep foci of increased T2/fluid-attenuation inversion recovery signal intensity.

CONCLUSIONS

We describe 8 cases of POWV encephalitis in Massachusetts and New Hampshire in 2013-2015. Prior to this, there had been only 2 cases of POWV encephalitis identified in Massachusetts. These cases may represent emergence of this virus in a region where its vector, I. scapularis, is known to be prevalent or may represent the emerging diagnosis of an underappreciated pathogen. We recommend testing for POWV in patients who present with encephalitis in the spring to fall in New England.

Abstract WMP77: Neurovascular Complications During Long-term Left Ventricular Assist Device (LVAD) Support: Single Center Experience

Introduction: Left ventricular assist devices (LVAD) have emerged as the standard of care for treating patients with advanced heart failure refractory to maximal medical therapy. Postoperative cerebrovascular complications are an important cause of morbidity and decreased quality of life. However, the literature contains little data on the incidence, predictors, and outcome of stroke.

Hypothesis: We aimed to determine the incidence of cerebrovascular complications, their type, and association with stroke risk factors and anticoagulation therapy.

Methods: Data were collected prospectively on all patients with LVADs implanted at BWH. Categorical variables were tested by Chi-square.

Results: From 2007 to 2015, 151 patients (123 male; median age 57) underwent implantation of HeartMate II LVAD: 79 bridge to transplant, 62 destination therapy, and 10 bridge to candidacy.

Strokes occurred in 31 patients (21%). Risk of stroke did not correlate with sex (25 male, 6 female) or age (median at stroke onset 57). Seventeen acute ischemic strokes (AIS) occurred in 16 patients and 17 intracerebral hemorrhages (ICH) occurred in 15 patients. Four of the AIS were complicated by secondary hemorrhage. Events occurred at a mean of 362 days from implantation (range 5 days-6 years 8 months).

All patients except one were on warfarin at time of stroke (goal INR 2-3.5). Mean INR at AIS onset was 2.3 compared to 3.0 for ICH. Of the 15 ICH patients, 3 had supratherapeutic INR > 3.5. Eleven of the 16 AIS patients were also receiving ASA, 1 ASA + dipyridamole, 1 ASA + dipyridamole + bivalirudin. One received ASA only. All ICH patients and all those with AIS with secondary hemorrhage were on ASA.

Patients with COPD were more likely to have a stroke (p = 0.0006); 30 of the 151 patients had COPD and 13 of them (43%) had strokes. Risk of stroke did not correlate with DM, HTN, hyperlipidemia, CKD, PAD, AF, or prior stroke.

Nineteen of 31 patients with stroke versus 22 of 120 without stroke died (mortality 61 v 18 %; p << 0.001).

Conclusions: Stroke is an important cause of major morbidity and mortality in patients on LVAD support. Patients with COPD are at an increased risk of stroke. Further studies addressing post-LVAD stroke risk, prevention, and treatment are warranted.

Cerebrovascular complications of pregnancy and the postpartum period

Cerebrovascular complications of pregnancy, though uncommon, threaten women with severe morbidity or death, and they are the main causes of major long-term disability associated with pregnancy. In this review, we discuss the epidemiology, pathophysiology, presentation and diagnosis, and management and outcomes of ischemic and hemorrhagic stroke and cerebral venous thrombosis. We also discuss the posterior reversible encephalopathy syndrome, the reversible cerebral vasoconstriction syndrome including postpartum cerebral angiopathy, and their relationship as overlapping manifestations of pre-eclampsia-eclampsia.

Elevated rates of intracerebral hemorrhage in individuals from a US clinical care HIV cohort

OBJECTIVE

To compare rates of intracerebral hemorrhage (ICH) in HIV-infected and uninfected individuals in a large clinical care cohort and to assess risk factors associated with ICH.

METHODS

We identified incident ICH in HIV-infected and uninfected control cohorts from the Partners Health Care system using ICD-9-CM codes. We constructed Cox proportional hazards models to estimate adjusted hazard ratios for HIV infection and other predictors of ICH.

RESULTS

The incidence rate of ICH was 2.29 per 1,000 person-years in HIV-infected individuals compared with 1.23 per 1,000 person-years in uninfected individuals, with an unadjusted incidence rate ratio of 1.85 (95% confidence interval 1.37-2.47, p < 0.001). In a multivariable model, HIV infection was independently associated with a higher hazard of ICH, although its effect diminished with increasing age. Female sex was associated with a lower hazard of ICH in the uninfected cohort but not in the HIV cohort. CD4 count <200 × 10(6) cells/L and anticoagulant use were predictive of ICH.

CONCLUSIONS

HIV infection conferred an increased adjusted hazard of ICH, which was more pronounced in young patients and in women.

Predicting hematoma expansion after primary intracerebral hemorrhage

IMPORTANCE

Many clinical trials focus on restricting hematoma expansion following acute intracerebral hemorrhage (ICH), but selecting those patients at highest risk of hematoma expansion is challenging.

OBJECTIVE

To develop a prediction score for hematoma expansion in patients with primary ICH.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study at 2 urban academic medical centers among patients having primary ICH with available baseline and follow-up computed tomography for volumetric analysis (817 patients in the development cohort and 195 patients in the independent validation cohort).

MAIN OUTCOMES AND MEASURES

Hematoma expansion was assessed using semiautomated software and was defined as more than 6 mL or 33% growth. Covariates were tested for association with hematoma expansion using univariate and multivariable logistic regression. A 9-point prediction score was derived based on the regression estimates and was subsequently tested in the independent validation cohort.

RESULTS

Hematoma expansion occurred in 156 patients (19.1%). In multivariable analysis, predictors of expansion were as follows: warfarin sodium use, the computed tomography angiography spot sign, and shorter time to computed tomography (≤ 6 vs >6 hours) (P < .001 for all), as well as baseline ICH volume (<30 [reference], 30-60 [P = .03], and >60 [P = .005] mL). The incidence of hematoma expansion steadily increased with higher scores. In the independent validation cohort (n = 195), our prediction score performed well and showed strong association with hematoma expansion (odds ratio, 4.59; P < .001 for a high vs low score). The C statistics for the score were 0.72 for the development cohort and 0.77 for the independent validation cohort.

CONCLUSIONS AND RELEVANCE

A 9-point prediction score for hematoma expansion was developed and independently validated. The results open a path for individualized treatment and trial design in ICH aimed at patients at highest risk of hematoma expansion with maximum potential for therapeutic benefit.

Coma from wall suction-induced CSF leak complicating spinal surgery

A 72-year-old woman was admitted for elective L4/L5 laminectomy. The operative procedure was extradural, and a Jackson-Pratt (JP) drain was placed in the tissue bed and set to wall suction during skin closure. During closure, the patient developed a 15 s period of asystole. The patient was haemodynamically stable, but was comatose for 3 days postoperatively. Cardiac enzymes and EEG were unrevealing. Head CT showed traces of subarachnoid haemorrhage and signs suggestive of cerebral anoxia. JP drain at the incision produced 170-210 mL/day of fluid, positive for β-2 transferrin, indicating cerebrospinal fluid (CSF). The patient fully returned to baseline on hospital day 10. MRI on hospital day 8 normalised. The reversible coma and radiographic findings were most consistent with acute intracranial hypotension relating to acute loss of CSF. Because radiographic findings can mimic hypoxic-ischaemic injury, acute intracranial hypotension should be considered in the differential diagnosis of postoperative coma after cranial or spinal surgery.

Cerebrovascular disorders complicating pregnancy

PURPOSE OF REVIEW

This article discusses the physiologic changes of pregnancy and how they affect risk of ischemic and hemorrhagic stroke and then reviews epidemiology, diagnosis, and treatment of ischemic and hemorrhagic stroke in pregnancy and the puerperium.

RECENT FINDINGS

This article updates our understanding of the relationship of preeclampsia/eclampsia to the posterior reversible encephalopathy syndrome and the reversible cerebral vasoconstriction syndrome, emphasizing their shared pathogenesis. It reviews the most recent data and offers recommendations concerning the use of thrombolytic and other revascularization therapies for pregnancy-related strokes.

SUMMARY

Although cerebrovascular complications are uncommon occurrences during pregnancy and the puerperium, stroke is still the most common seriously disabling complication of pregnancy. Therefore, stroke and other vascular issues raise questions about the best evaluation and management that is safe for mother and child.

Abstract W MP28: Early Elevation of Plasma Soluble Fms-Like Tyrosine Kinase-1 is Associated With Poor Functional Outcome After Subarachnoid Hemorrhage

Background: Vasospasm (VSP) and brain injury following subarachnoid hemorrhage (SAH) are associated with tissue hypoxia and vascular endothelial growth factor (VEGF) release. Soluble Fms-like tyrosine kinase-1 (sFlt-1), a truncated soluble form of VEGF receptor-1, is an endogenous VEGF inhibitor released in response to hypoxia and nitric oxide deficiency. SFlt-1 is anti-angiogenic and mediates endothelial dysfunction. We hypothesize sFlt-1 elevation may be associated with VSP and poor SAH outcome.

Methods: We prospectively enrolled consecutive SAH subjects, banked serial blood samples, and evaluated their modified Rankin scores (mRS) at 3 month intervals. Poor functional outcome was defined as mRS>2. Angiographic VSP was defined as >50% reduction in caliber of any vessel on post-SAH day 7 cerebral angiogram. In 63 SAH subjects, we compared plasma sFlt-1 by ELISA on post-SAH days 3 and 5 by VSP and outcome status using Wilcoxon rank sum or Student’s t-test depending on data distribution. Bonferroni correction was used for multiple comparisons. Logistic regression was used to adjust for confounders. Associations were measured using Pearson’s or Spearman’s correlation depending on data distribution.

Results: Twenty-seven subjects (43%) had poor 3-month outcome and 31 (49%) developed VSP. Elevated sFlt-1 level on post-SAH day 3 was associated with poor 3-month outcome (p=0.02) while post-SAH day 5 sFlt-1 level showed no association. SFlt-1 levels were not associated with Hunt and Hess (HH) or Fisher grades or with VSP. SFlt-1 was inversely correlated to VEGF (p=0.04, r=0.26). Post-SAH day 3 sFlt-1 level was independently associated with poor SAH outcome after adjustment for HH grade, age, and VEGF level (p=0.03). VEGF was not associated with VSP or SAH outcome.

Conclusion: Early elevation of plasma sFlt-1 on post-SAH day 3 is independently associated with poor 3-month SAH outcome after adjustment for clinical predictors of SAH outcome and for VEGF. Inverse correlation suggests possible negative feedback control between sFlt-1 and VEGF in SAH. Future studies are necessary to determine the source of sFlt-1 in SAH and its role in SAH-associated brain injury. Replication in a larger cohort is necessary to validate sFlt-1 as a potential biomarker for SAH outcome.

Abstract 197: The TeleStroke Mimic (TM) Score: A Prediction Rule for Identifying Stroke Mimics Evaluated in a Telestroke Network

Intro: Up to 30% of acute stroke evaluations are deemed stroke mimics (SM). SMs are likely common in telestroke as well, and a model to help a priori identify these patients might be clinically useful.

Methods: We used 829 consecutive patients from 01/04 to 04/13 in our internal New England based Partners TeleStroke Network for a derivation cohort and 332 cases for internal validation. External validation was performed on 226 cases from 01/08-08/12 in our Partners National TeleStroke Network. Performance of a prediction rule developed with stepwise logistic regression was characterized by ROC curve analysis.

Result: There were 23% SM in the derivation, 24% in the internal and 22% in external validation cohorts based on final clinical diagnosis. Compared to those with ischemic cerebrovascular disease (CVD), SM had lower mean age, fewer vascular risk factors, more often prior seizure and a different profile of presenting symptoms (Table 1). The TM-Score (Figure 1) was based on factors independently associated with SM status including age, medical history (atrial fibrillation, hypertension, seizures), facial weakness and NIHSS >14. The TM-Score performed well on ROC curve analysis (derivation cohort AUC=0.753, internal validation AUC=0.710, external validation AUC=0.770).

Conclusion: As telestroke consultation expands, increasing numbers of SM patients are being evaluated. These patients differ substantially from their ischemic CVD counterparts in their vascular risk profiles and other characteristics. Decision-support tools based on predictive models, like the one we propose, may help highlight these differences during complex, time-critical telestroke evaluations.

Abstract W MP29: CSF MicroRNA-181b is Associated With Poor 6-Month Outcome Following Subarachnoid Hemorrhage

Background: Early brain injury and vasospasm (VSP) in subarachnoid hemorrhage (SAH) are associated with inflammation and release of TNFα, which correlates with poor SAH clinical outcome. TNFα regulates the expression of microRNA (miR) 181b, which mediates NF-κB signaling and is known to exacerbate ischemic stroke in animal models. MiRs have higher stability in biological fluids than peptides and may be candidate clinical biomarkers. We hypothesize that miR-181b is present in SAH CSF and may be associated with SAH outcome.

Methods: We prospectively enrolled consecutive SAH subjects, banked serial CSF samples, and evaluated their modified Rankin scores (mRS) via telephone follow-up every 3 months. Poor functional outcome was defined as mRS>2. Angiographic VSP was defined as >50% reduction in caliber of any vessel on post-SAH day 7 cerebral angiogram. In 54 SAH subjects, we compared CSF miR-181b and 26a (as control) by quantitative PCR on post-SAH day 3 with respect to VSP and outcome using Student’s t-test after log-transformation of data with non-normal distribution. Associations were measured using Pearson’s or Spearman’s correlation depending on data distribution.

Results: Twenty-seven subjects (50%) developed VSP and 21 (39%) had poor 6-month outcome. MiRs-181b and 26a were consistently measurable in SAH CSF, and miR levels were not associated with Hunt and Hess or Fisher grades. Elevation of CSF miR-181b was associated with poor 6-month outcome in SAH (p=0.04). CSF miR-181b inversely correlated with blood TNFα (r=0.74, p=0.0001). CSF miR-181b was not associated with VSP. CSF miR-26a was not associated with VSP or with clinical outcome in SAH.

Conclusion: MiR-181b is present in human CSF after SAH and early elevation of CSF miR-181b is associated with poor 6-month outcome but not with VSP after SAH. Lack of association between control miR-26a and outcome suggests that association between miR-181b and SAH outcome is not due to a non-specific miR surge in more severe cases. Inverse correlation between blood TNFα and CSF miR-181b suggests TNFα may mediate miR-181b release into CSF. Future mechanistic studies on the role of miR-181b in SAH-related brain injury and validation studies in larger cohorts are necessary to understand the role of miR-181b as a SAH biomarker.

White matter hyperintensity volume correlates with matrix metalloproteinase-2 in acute ischemic stroke

BACKGROUND

White matter hyperintensity (WMH), a common radiographic finding associated with stroke risk and outcome, has been linked to matrix metalloproteinase (MMP) activity and increased levels of oxidative stress in nonstroke populations. We sought to determine whether WMH severity is associated with plasma levels of MMPs and oxidative stress (F2-isoprostane) in subjects with acute ischemic stroke (AIS).

METHODS

We measured plasma biomarker levels at baseline and 48 hours in consecutive AIS subjects. White matter hyperintensity volume (WMHv) was quantified on admission magnetic resonance imaging using a validated semiautomated protocol, and Spearman correlation coefficients were derived for all measured biomarkers.

RESULTS

We enrolled 405 AIS subjects (mean age 70±15 years; 58% male; median WMHv 3.4 cm3, interquartile range 1.4-9.5). WMHv and age were strongly correlated (ρ=.57, P<.0001). WMHv and MMP-2 levels were correlated at baseline (ρ=.23, P<.0001) and at 48 hours poststroke (ρ=.19, P=.002). In multivariate analysis, 48-hour MMP-2 levels were independently associated with WMHv (β=.12, P=.04). MMP-9 and F2-isioprostane levels did not correlate with WMHv.

CONCLUSIONS

In AIS patients, MMP-2 levels are associated with the pre-existing burden of WMH. If validated, these findings may further elucidate the role of MMP-2 in pathophysiology of chronic cerebrovascular injury, such as WMH, and in brain susceptibility to acute ischemia.