Advances in Management of the Stroke Etiology One-Percenters

PURPOSE OF REVIEW

Uncommon causes of stroke merit specific attention; when clinicians have less common etiologies of stoke in mind, the diagnosis may come more easily. This is key, as optimal management will in many cases differs significantly from "standard" care.

RECENT FINDINGS

Randomized controlled trials (RCT) on the best medical therapy in the treatment of cervical artery dissection (CeAD) have demonstrated low rates of ischemia with both antiplatelet and vitamin K antagonism. RCT evidence supports the use of anticoagulation with vitamin K antagonism in "high-risk" patients with antiphospholipid antibody syndrome (APLAS), and there is new evidence supporting the utilization of direct oral anticoagulation in malignancy-associated thrombosis. Migraine with aura has been more conclusively linked not only with increased risk of ischemic and hemorrhagic stroke, but also with cardiovascular mortality. Recent literature has surprisingly not provided support the utilization of L-arginine in the treatment of patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); however, there is evidence at this time that support use of enzyme replacement in patients with Fabry disease. Additional triggers for reversible cerebral vasoconstriction syndrome (RCVS) have been identified, such as capsaicin. Imaging of cerebral blood vessel walls utilizing contrast-enhanced MRA is an emerging modality that may ultimately prove to be very useful in the evaluation of patients with uncommon causes of stroke. A plethora of associations between cerebrovascular disease and COVID-19 have been described. Where pertinent, authors provide additional tips and guidance. Less commonly encountered conditions with updates in diagnosis, and management along with clinical tips are reviewed.

Acute telestroke evaluations during the COVID-19 pandemic

We sought to analyze the effect of COVID-19 on telestroke requests and to characterize patients remotely evaluated for acute ischemic stroke (AIS) during this time. This study is a retrospective database review of all telestroke requests at one academic vascular neurology center telestroke network with seven remote sites in the USA between March 15 and April 30, 2020. Data were compared with historical cohort spanning same time frame in 2019 using parametric or nonparametric methods as appropriate. Among telestroke requests, characteristics of age, gender, race/ethnicity, National Institutes of Health Stroke Scale (NIHSS), primary diagnosis of AIS or transient ischemic attack (TIA), and number of patients receiving intravenous alteplase (IV-rtPA) and endovascular therapy (ET) were recorded. There was a 53% decrease in telestroke evaluation requests in 2020 from 2019 (p < 0.00001). Mean NIHSS in 2020 was 9.1 (SD ± 8.4) and mean NIHSS in 2019 was 7.2 (SD ± 7.3) (p = 0.122). Among patients with primary diagnosis of suspected AIS or TIA, mean age was 60.5 years in 2020 (SD ± 17.5) and mean age of 67.0 years in 2019 (SD ± 16.0) (p = 0.038). A significant lower number of telestroke evaluations were performed with a higher mean NIHSS overall and a lower mean age among AIS/TIA-suspected patients. Higher NIHSS and severity in all telestroke evaluations reflect neurological manifestations of AIS and mimics, possibly influenced by COVID-19. The younger age of those with suspected AIS or TIA reflects thrombotic complications in atypical stroke populations.

Timing of Anticoagulation after Stroke in Patients with Non-Valvular Atrial Fibrillation Assessment of Provider Practices

BACKGROUND

Optimal timing of oral anticoagulation (TOAC) in acute ischemic stroke (AIS) in patients with atrial fibrillation (AF) is unknown. The risk of recurrent ischemic events when treatment is delayed is often weighed against that of hemorrhagic transformation (HT) when anticoagulation is started in the subacute phase, especially in moderate to large infarctions. Despite substantial evidence for the benefit of oral anticoagulation (OAC) in reducing stroke recurrence, current nationally recognized practice guidelines do not provide clear recommendations on the TOAC after AF-related AIS.

MATERIALS AND METHODS

We surveyed neurologists on therapeutic approaches to timing of anticoagulation after stroke in patients with AF (without moderate or severe mitral stenosis or a mechanical heart valve) using an online questionnaire. Several ischemic and hemorrhagic stroke scenarios with various stroke sizes, locations, and high-risk thrombotic complications were presented, and survey respondents were asked to provide post-stroke timeframe for TOAC. Practice background, specialty and years of experience of respondents were recorded.

RESULTS

Majority of participants favored early initiation of OAC in small infarcts. In moderate to larger infarct burden, or when ischemia was complicated by HT, there was an overall trend to delay any initiation of OAC, irrespective of specialty or years of experience. The overt presence of an additional cardiac embolic source such as cardiac thrombus led decisions for early anticoagulation.

CONCLUSION

Although general practice trends were captured, optimal TOAC following AIS in AF remains unknown. Further research is warranted to determine optimal timing and anticoagulant selection.

Abstract P363: Predictors of Utility of Advanced Cardiac Imaging in Revealing Cryptogenic Stroke Etiology

Introduction: Advanced cardiac imaging (ACI), including transesophageal echocardiogram (TEE), cardiac CT and cardiac MRI, is widely considered a crucial element in the work-up of cryptogenic and ESUS stroke. Current data on diagnostic yields are variable, though, and selection of patients to undergo such imaging is largely anecdotal.

Methodology: We conducted a retrospective case series review of all cryptogenic ischemic strokes who received ACI, admitted to a large urban academic single-center over a 2.5-year period. Patient characteristics and imaging findings were analyzed to determine diagnostic yields and to identify positive and negative predictors that ACI would uncover etiology.

Results: Out of 277 total cryptogenic ischemic strokes reviewed, ACI determined etiology in 20 cases (7.2%). Median age was 61 (IQR = 52-73). Patient sex was 49.5% female. Race demographic was 1.8% Asian, 50.9% black, 14.1% latino(a), and 33.2% white. Etiology was found by TEE in 16 of 20 cases, and the most common finding was left atrial thrombus/smoke. Latino(a) race was significantly more likely (15.4%) for ACI to find etiology and white race was significantly less likely (1.1%), p = .03 and .005, respectively. The table included shows other notable findings. Analogous trends were observed in a subgroup analysis of patients greater or equal to 60 years old.

Conclusion: Our data indicate that in cryptogenic stroke premorbid non-use of antithrombotic, elevated troponin and left atrial dilatation are each individually associated with increased likelihood that ACI will find an etiology. Meanwhile, patients with diabetes mellitus are significantly less likely to have etiology found by ACI; and, smokers with combined hypertension, hyperlipidemia, and diabetes mellitus trend towards ACI less frequently uncovering etiology. Finally, the data suggest potential racial disparities of finding etiology with ACI, the determinants of which remain to be studied.

Abstract P95: Characteristics of a Diverse Cohort of Stroke Patients With SARS-CoV-2 and Outcome by Sex

Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is associated with stroke. The role of sex on stroke outcome has not been investigated. We describe the characteristics of a diverse cohort of acute stroke patients with COVID-19 disease, and investigate the role of sex on outcome.

Methods: This is a retrospective study of patients with acute stroke and SARS-CoV-2 infection admitted between March 15 to May 15, 2020 to one of the six participating comprehensive stroke centers from Chicago metropolitan area. Baseline characteristics, stroke subtype, workup, treatment and outcome are presented as total number and percentage. Outcome at discharge was determined by the modified Rankin Scale Score (mRS). Variables and outcomes were compared for males and females using univariate and multivariate analysis.

Results: The study included 83 patients. Median age was 64 years and the majority were Blacks (47%) followed by Hispanics (28%) and whites (16%). Approximately 89% had at least one preexisting vascular risk factor (VRF). The most common complications were respiratory failure (59%) and septic shock (34%). Higher proportions of male experienced severe SARS-CoV-2 symptoms requiring ICU hospitalization (73% vs. 49%; p=0.04). When divided by stroke subtype, there were 77% ischemic, 19% intracerebral hemorrhage and 3% subarachnoid hemorrhage. The most common ischemic stroke etiologies were cryptogenic (39%) and cardioembolic (27%). Compared to female, males had higher mortality (38% vs. 13%; p=0.02) and were less likely to be discharged home (12% vs. 33%; p=0.04). After adjustment for age, race/ethnicity, and number of VRFs, mRS was higher in males than in females (OR=1.47, 95% CI=1.03-2.09)

Conclusion: In this cohort of SARS-CoV-2 stroke patients, most had clinical evidence of coronavirus infection on admission and preexisting VRFs. Severe in-hospital complications and worse outcomes after ischemic strokes were higher in males, than females.

Characteristics of a Diverse Cohort of Stroke Patients with SARS-CoV-2 and Outcome by Sex

•

COVID-19 disease is associated with stroke

•

All strokes subtypes are seen in association with COVID-19, with ischemic stroke being most prevalent

•

The most common etiology for ischemic stroke in SARS-CoV2 infection is cryptogenic

•

Sex plays an important role in stroke outcomes in patients with COVID-19 disease

•

Males have higher rates of ICU admission, in-hospital complications and more likely to have worse outcome at hospital discharge compare with females

Background and Purpose

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is associated with stroke. The role of sex on stroke outcome has not been investigated. To objective of this paper is to describe the characteristics of a diverse cohort of acute stroke patients with COVID-19 disease and determine the role of sex on outcome.

Methods

This is a retrospective study of patients with acute stroke and SARS-CoV-2 infection admitted between March 15 to May 15, 2020 to one of the six participating comprehensive stroke centers. Baseline characteristics, stroke subtype, workup, treatment and outcome are presented as total number and percentage or median and interquartile range. Outcome at discharge was determined by the modified Rankin Scale Score (mRS). Variables and outcomes were compared for males and females using univariate and multivariate analysis.

Results

The study included 83 patients, 47% of which were Black, 28% Hispanics/Latinos, and 16% whites. Median age was 64 years. Approximately 89% had at least one preexisting vascular risk factor (VRF). The most common complications were respiratory failure (59%) and septic shock (34%). Compared with females, a higher proportion of males experienced severe SARS-CoV-2 symptoms requiring ICU hospitalization (73% vs. 49%; p = 0.04). When divided by stroke subtype, there were 77% ischemic, 19% intracerebral hemorrhage and 3% subarachnoid hemorrhage. The most common ischemic stroke etiologies were cryptogenic (39%) and cardioembolic (27%). Compared with females, males had higher mortality (38% vs. 13%; p = 0.02) and were less likely to be discharged home (12% vs. 33%; p = 0.04). After adjustment for age, race/ethnicity, and number of VRFs, mRS was higher in males than in females (OR = 1.47, 95% CI = 1.03–2.09).

Conclusion

In this cohort of SARS-CoV-2 stroke patients, most had clinical evidence of coronavirus infection on admission and preexisting VRFs. Severe in-hospital complications and worse outcomes after ischemic strokes were higher in males, than females.

Acute Ischemic Stroke and COVID-19: Experience From a Comprehensive Stroke Center in Midwest US

Background: COVID-19 has been associated with increased risk of venous and arterial thromboembolism including ischemic stroke. We report on patients with acute ischemic stroke and concomitant COVID-19 in a diverse patient population. Methods: This is a retrospective analysis of patients hospitalized with acute ischemic stroke (AIS) and COVID-19 to our comprehensive stroke center in Chicago, IL, between March 1, 2020, and April 30, 2020. We reviewed stroke characteristics, etiologies, and composite outcomes. We then compared our cohort with historic patients with AIS without COVID-19 admitted in the same time frame in 2019 and 2020. Results: Out of 13 patients with AIS and COVID-19, Latinos and African-Americans compromised the majority of our cohort (76.8%), with age ranging from 31-80 years. Most strokes were cortical (84.6%) and more than 50% of patients had no identifiable source, and were categorized as embolic stroke of unknown source (ESUS). A trend toward less alteplase administration was noted in the COVID-19 stroke patients compared to the non-COVID group from 2020 and 2019 (7.1 vs. 20.7% p 0.435 and 7.1 vs. 27.2% p 0.178). Endovascular thrombectomy was performed in 3 (23%) patients. Systemic thrombotic complications occurred in 3 (23%) COVID-19 AIS patients. Median National Institutes of Health Stroke Scale and modified Rankin Scale at discharge were 11 (IQR 4-23) and 4 (IQR 3-4), respectively. In the logistic regression model corrected for age and sex, COVID-19 was associated with discharge to mRS > 2 (p 0.046, OR 3.82, CI 1.02-14.3). Eight patients (63.8%) were discharged home or to acute rehabilitation, and two deceased from COVID-19 complications. Conclusion: AIS in the setting of COVID-19 is associated with worse outcomes, especially among African-American and Latino populations. Large vessel disease with ESUS was common suggesting an increased risk of coagulopathy and endothelial dysfunction as a potential etiology.

Neurological manifestations and COVID-19: Experiences from a tertiary care center at the Frontline

OBJECTIVE

To report neurological manifestations seen in patients hospitalized with Coronavirus disease 2019 (COVID-19) from a large academic medical center in Chicago, Illinois.

METHODS

We retrospectively reviewed data records of 50 patients with COVID-19 who were evaluated by the neurology services from March 1, 2020 - April 30, 2020. Patients were categorized into 2 groups based on timing of developing neurological manifestations: the "Neuro first" group had neurological manifestations upon initial assessment, and the "COVID first" group developed neurological symptoms greater than 24 h after hospitalization. The demographics, comorbidities, disease severity and neurological symptoms and diagnoses of both groups were analyzed. Statistical analysis was performed to compare the two groups.

RESULTS

A total of 50 patients (48% African American and 24% Latino) were included in the analysis. Most common neurological manifestations observed were encephalopathy (n = 30), cerebrovascular disease (n = 20), cognitive impairment (n = 13), seizures (n = 13), hypoxic brain injury (n = 7), dysgeusia (n = 5), and extraocular movement abnormalities (n = 5). The "COVID-19 first" group had more evidence of physiologic disturbances on arrival with a more severe/critical disease course (83.3% vs 53.8%, p 0.025).

CONCLUSION

Neurologic manifestations of COVID-19 are highly variable and can occur prior to the diagnosis of or as a complication of the viral infection. Despite similar baseline comorbidities and demographics, the COVID-19 patients who developed neurologic symptoms later in hospitalization had more severe disease courses. Differently from previous studies, we noted a high percentage of African American and Latino individuals in both groups.

Acute Stroke Care in the Coronavirus Disease 2019 Pandemic

Coronavirus disease 2019 (COVID-19) is a pandemic respiratory disease with serious public health risk and has taken the world off-guard with its rapid spread. As the COVID-19 pandemic intensifies, overwhelming the healthcare system and the medical community, current practice for the management of acute ischemic stroke (AIS) will require modification, and guidelines should be relaxed while maintaining high standard quality of care. The aim of these suggestions is to avoid contributing to the rapid spread of COVID-19 as well as to conserve what are likely to be very limited resources (including personnel, intensive care/hospital beds as well as physicians) while maintaining high quality care for patients with AIS. We present our recommendations for the management of acute stroke during the COVID-19 pandemics.

Eptifibatide use following emergent carotid stenting in acute anterior circulation ischemic stroke with tandem occlusion

BACKGROUND

Early revascularization of the extracranial internal carotid artery in acute anterior circulation ischemic stroke (ACIS) is feasible and may improve clinical outcome. When a stent is deployed, antithrombotic agents should be administered peri-procedurally to ensure stent patency. Our institution implemented a protocol for the use of eptifibatide as a means of maintaining stent patency in the treatment of ACIS associated with cervical internal carotid artery occlusion.

METHODS

Our internal database was queried for patients who received emergent endovascular therapy (ET) for ACIS with stent placement and eptifibatide administration between July 2016 and 2019.

RESULTS

Twenty nine patients met the study criteria. The etiology was large artery atherosclerosis in 26 cases. Two patients had a dissection (7%), and one had a carotid occlusion related to a recent carotid endarterectomy. Mean NIHSS was 14. Sixteen patients received IVrtPA. Extracranial-intracranial tandem occlusion (TO) was present in 21 of cases. All patients received an eptifibatide bolus followed by an infusion for approximately 24 hours post stent deployment. Head CT was obtained prior to initiation of oral dual antiplatelet therapy with aspirin and clopidogrel. Successful recanalization was achieved in all patients with no evidence of downstream embolization. Symptomatic intracerebral hemorrhage occurred in one patient. Stent occlusion occurred in two patients, only one of which was symptomatic. Favorable clinical outcome with mRS ≤ 2 at 3 months was achieved in seventeen patients.

CONCLUSIONS

The use of eptifibatide post procedure was associated with low risk of symptomatic intracranial hemorrhage, including in patients treated with rtPA.

Abstract TP87: Gaze Deviation on Initial CT as Predictor of Large Vessel Occlusion

Introduction: Treatment of large vessel occlusion (LVO) stroke is traditionally preceded by imaging evaluation of vessels using computed tomographic angiography (CTA). However, CTA may not be feasible due to renal dysfunction or contrast allergy; in smaller hospitals, CTAs may not be easily obtainable. Given this, early LVO signs on initial non-contrast computed tomography (CT) could prove practical, such as the hyperdense vessel sign (HVS). We aimed to investigate the sensitivity of another potential indicator of LVO on CT, gaze deviation, and to compare it to HVS.

Methods: We conducted a retrospective analysis of consecutive patients with anterior circulation LVO stroke admitted to a comprehensive stroke center from July 2015 to July 2018, who underwent endovascular therapy (ET). All patients had confirmed LVO on CTA prior to ET. Initial head CTs were reviewed for HVS and gaze deviation by two neurology-trained examiners and compared to official diagnostic radiology reports. Two analyses were performed: detection of HVS and gaze deviation by each examiner, diagnostic radiologist with sensitivity calculation; and interrater agreement for identification of HVS and gaze deviation using a Kappa Coefficient between the two primary examiners and between diagnostic radiologist.

Results: A total of 121 patients were included. Sensitivity of HVS by examiner 1 was 46% (56/121) and 2 was 60% (72/121). Sensitivity of HVS by in-house radiology was 36% (42/116) and OSH radiology was 27% (24/90). Sensitivity of gaze deviation by examiner 1 was 65% (79/121) and 2 was 79% (95/121). Inter-rater reliability of HVS for examiners 1 and 2 had substantial agreement (K=0.64), and for in-house and OSH radiology had fair agreement (K=0.27). Inter-rater reliability of gaze deviation for examiners 1 and 2 had substantial agreement (K=0.69). No radiology report noted gaze deviation, despite 2 reports of unrelated ocular findings.

Conclusions: Gaze deviation may be a more sensitive and more reliable indicator of LVO on initial non-contrast head CT than the hyperdense vessel sign. This is the largest sample size to examine and directly compare signs of LVO. More research should be invested in this and other indicators of LVO that can assist in the efficient triage and treatment of these severe strokes.

Abstract TP59: Experience With Endovascular Therapy in Acute Ischemic Stroke Patients Presenting With Low National Institute of Health Stroke Scale Scores

Background: Endovascular thrombectomy (ET) is indicated for select patients with anterior circulation large vessel occlusion (ACLVO) with NIHSS > 6. Safety and efficacy of ET in patients with NIHSS <6 and ACLVO is an area of clinical equipoise; we present our experience with this population.

Methods: Internal ischemic stroke database was queried for patients with admission NIHSS <6 from 1/2015 to 6/2018. NIHSS on presentation, cortical signs, use of ET (on arrival or after clinical decline) and outcomes were retrospectively collected. Outcomes were compared between patients taken directly for ET and those observed using Mann Whitney U.

Results: Of 173 admissions with NIHSS <6 upon arrival, 15 patients had ACLVO. Of those, all had cortical signs; 8 patients were admitted and monitored, 7 patients went directly to ET . Of the 8 monitored patients, 3 (38%) received IVtPA, 6 (75%) underwent rescue ET after clinical decline, all with favorable aspects . Arrival mean NIHSS was 3.3 (4.6), NIHSS at time of ET was 10.6 (7.4). Occlusions were located in the first branch of the middle cerebral artery (M1) in 3 cases, with one case each of M2, internal carotid artery (ICA) and tandem occlusion. A symptomatic intracerebral hemorrhage occurred in a patient with re-occlusion, stent placement and IV antiplatelet use. Five patients (63%) were discharged to an acute rehab facility, the remaining 27% were discharged to home, with NIHSS of 7.7 (7.2) on discharge and mRS of 1.75 (1.5) at 90-day follow-up. Of the 7 patients who proceeded directly to ET, arrival NIHSS was 2.3 (2.2), 43% received IVtPA, occlusions were present in the terminal ICA in all cases, with tandem occlusions additionally present in 3 (43%). One patient clinically worsened and was found to have vasospasm. This same patient was discharged to rehab, the remainder (85.8%) were discharged to home. Discharge stroke scale (mean 1.4, SD 2.2) approached significance (U=11, p=0.052) compared to the observation group, discharge location (chi 3.6, p=0.58) and discharge mRS did not (U=12, p=0.28).

Discussion: Despite the low sample size, there was a trend toward significance in discharge NIHSS in favor of patients that were taken directly for ET. Further study regarding management of patients with low NIHSS and LVO is merited.

Abstract TP293: Errors in Estimation of Body Weight in Thrombolysis for Acute Ischemic Stroke

Introduction: Intravenous tissue plasminogen activator (IVtPA) is a proven treatment in acute ischemic stroke but relies on weight-based dosing in a time sensitive manner. Errors in body weight estimation are common and may result in over or under-dosing of IVtPA.

Methods: With IRB approval, we prospectively screened 99 consecutive patients who received IVtPA for suspected acute ischemic stroke from November 1, 2015 to July 1, 2016 as part of a prospective IVtPA study. Patients were included in this analysis who had complete data. Data was collected on patient demographics, National Institutes of Health Stroke Scale (NIHSS), body weight, and times of last known normal (LKN) and IVtPA administration. A significant error in IVtPA dosing was defined as a >10% difference in actual versus calculated IVtPA dose.

Results: Among 42 patients prospectively enrolled, the mean age was 65.8 years (range, 32 to 89) and 30 (79%) of patients were transfers from outside Emergency Rooms. Mean time from LKN to IVtPA administration was 2.4 hours (range. 0.7 to 4.8). Initial pre-IVtPA mean NIHSS was 14 (range, 3 to 26). The mean % error in IVtPA dose was +1.9% (range, -29% to + 21%). Ten patients (24%) had a significant error in IVtPA dosing of > 10% of the dose, and 8 (80%) were over-doses. Patients with significant IVtPA dosing error did not differ in terms of age (65.8 vs 65.8, p 0.99), sex (female 55.6% vs 38.9%, p 0.45), race (white 70% vs 47%, p 0.28), height (164.8 vs 171.0 cm, p 0.1), or time from LKN to IVtPA (2.8 vs 2.3, p 0.15). Patients with significant IVtPA dosing errors had significantly lower baseline weight (70.3 vs 90.0 kilograms, p 0.029) and higher NIHSS (18.7 vs 12.6, p 0.018).

Conclusion: Dosing errors of > 10% of the calculated IVtPA dose occur in nearly one-quarter of acute stroke patients treated in the community, and patients with lower weight and higher NIHSS were at higher risk of dosing errors.

Neurocardiology

Neurocardiology refers to the interplay between the nervous system and the cardiovascular system. Stress-related cardiomyopathy exemplifies the brain-heart connection and occurs in several conditions with acute brain injury that share oversympathetic activation. The brain's influences on the heart can include elevated cardiac markers, arrhythmias, repolarization abnormalities on electrocardiogram, myocardial necrosis, and autonomic dysfunction. The neurogenic stunned myocardium in aneurysmal subarachnoid hemorrhage represents one end of the spectrum, and is associated with an explosive rise in intracranial pressure that results in excess catecholamine state and possibly CBN. A brain-heart link is more known to cardiologists than neurologists. This chapter provides some insight into the pathophysiology of these pathologic neurocardiac states and their most appropriate management relevant to neurologists.