International stroke genetics consortium recommendations for studies of genetics of stroke outcome and recovery.

Numerous biological mechanisms contribute to outcome after stroke, including brain injury, inflammation, and repair mechanisms. Clinical genetic studies have the potential to discover biological mechanisms affecting stroke recovery in humans and identify intervention targets. Large sample sizes are needed to detect commonly occurring genetic variations related to stroke brain injury and recovery. However, this usually requires combining data from multiple studies where consistent terminology, methodology, and data collection timelines are essential. Our group of expert stroke and rehabilitation clinicians and researchers with knowledge in genetics of stroke recovery here present recommendations for harmonizing phenotype data with focus on measures suitable for multicenter genetic studies of ischemic stroke brain injury and recovery. Our recommendations have been endorsed by the International Stroke Genetics Consortium.

Association Between Hospital Volumes and Clinical Outcomes for Patients With Nontraumatic Subarachnoid Hemorrhage.

Background Previous studies of patients with nontraumatic subarachnoid hemorrhage (SAH) suggest better outcomes at hospitals with higher case and procedural volumes, but the shape of the volume-outcome curve has not been defined. We sought to establish minimum volume criteria for SAH and aneurysm obliteration procedures that could be used for comprehensive stroke center certification. Methods and Results Data from 8512 discharges in the National Inpatient Sample (NIS) from 2010 to 2011 were analyzed using logistic regression models to evaluate the association between clinical outcomes (in-hospital mortality and the NIS-SAH Outcome Measure [NIS-SOM]) and measures of hospital annual case volume (nontraumatic SAH discharges, coiling, and clipping procedures). Sensitivity and specificity analyses for the association of desirable outcomes with different volume thresholds were performed. During 8512 SAH hospitalizations, 28.7% of cases underwent clipping and 20.1% underwent coiling with rates of 21.2% for in-hospital mortality and 38.6% for poor outcome on the NIS-SOM. The mean (range) of SAH, coiling, and clipping annual case volumes were 30.9 (1-195), 8.7 (0-94), and 6.1 (0-69), respectively. Logistic regression demonstrated improved outcomes with increasing annual case volumes of SAH discharges and procedures for aneurysm obliteration, with attenuation of the benefit beyond 35 SAH cases/year. Analysis of sensitivity and specificity using different volume thresholds confirmed these results. Analysis of previously proposed volume thresholds, including those utilized as minimum standards for comprehensive stroke center certification, showed that hospitals with more than 35 SAH cases annually had consistently superior outcomes compared with hospitals with fewer cases, although some hospitals below this threshold had similar outcomes. The adjusted odds ratio demonstrating lower risk of poor outcomes with SAH annual case volume ≥35 compared with 20 to 34 was 0.82 for the NIS-SOM (95% CI, 0.71-094; P=0.0054) and 0.80 (95% CI, 0.68-0.93; P=0.0055) for in-hospital mortality. Conclusions Outcomes for patients with SAH improve with increasing hospital case volumes and procedure volumes, with consistently better outcomes for hospitals with more than 35 SAH cases per year.

Posterior reversible encephalopathy syndrome in patients with COVID-19.

OBJECTIVE: To report four patients with coronavirus disease 2019 (COVID-19) who developed posterior reversible encephalopathy syndrome (PRES). METHODS: Patient data was abstracted from medical records at Weill Cornell Medical Center. RESULTS: Four patients with SARS-CoV-2 infection and PRES were identified. The patients' ages ranged from 64 to 74 years, and two were women. All four patients were admitted to the hospital with acute respiratory distress syndrome requiring intensive care unit admission and mechanical ventilation. PRES was diagnosed after persistent confusion, lethargy, new focal neurological deficits, or seizures were noted, with evidence of seizures on electroencephalogram for two of the patients. Imaging confirmed the presence of cerebral vasogenic edema. All four patients had elevated blood pressure and renal injury in the days preceding PRES diagnosis, as well as evidence of systemic inflammation and systemic hypercoagulability. Symptoms of PRES improved with blood pressure control. CONCLUSIONS: Our four cases demonstrate the occurrence of PRES in critically-ill patients with COVID-19. PRES should be considered in the differential for acute neurological deficits and seizures in this setting.

SCAI expert consensus statement on operator and institutional requirements for PFO closure for secondary prevention of paradoxical embolic stroke: The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists.

Until recently, evidence to support Patent Foramen Ovale (PFO) closure for secondary prevention of recurrent stroke has been controversial. Publication of high-quality evidence from randomized clinical trials and the subsequent FDA approval of two devices for percutaneous PFO closure is expected to increase the volume of PFO closure procedures not only in the United States but worldwide. As this technology is disseminated broadly to the public, ensuring the safe and efficacious performance of PFO closure is essential to mitigate risk and avoid unnecessary procedures. This document, prepared by a multi-disciplinary writing group convened by the Society for Cardiovascular Angiography and Interventions and including representatives from the American Academy of Neurology, makes recommendations for institutional infrastructure and individual skills necessary to initiate and maintain an active PFO/stroke program, with emphasis on shared decision making and patient-centered care.

Development of a Non-invasive Device for Swallow Screening in Patients at Risk of Oropharyngeal Dysphagia: Results from a Prospective Exploratory Study.

Oropharyngeal dysphagia is prevalent in several at-risk populations, including post-stroke patients, patients in intensive care and the elderly. Dysphagia contributes to longer hospital stays and poor outcomes, including pneumonia. Early identification of dysphagia is recommended as part of the evaluation of at-risk patients, but available bedside screening tools perform inconsistently. In this study, we developed algorithms to detect swallowing impairment using a novel accelerometer-based dysphagia detection system (DDS). A sample of 344 individuals was enrolled across seven sites in the United States. Dual-axis accelerometry signals were collected prospectively with simultaneous videofluoroscopy (VFSS) during swallows of liquid barium stimuli in thin, mildly, moderately and extremely thick consistencies. Signal processing classifiers were trained using linear discriminant analysis and 10,000 random training-test data splits. The primary objective was to develop an algorithm to detect impaired swallowing safety with thin liquids with an area under receiver operating characteristic curve (AUC) > 80% compared to the VFSS reference standard. Impaired swallowing safety was identified in 7.2% of the thin liquid boluses collected. At least one unsafe thin liquid bolus was found in 19.7% of participants, but participants did not exhibit impaired safety consistently. The DDS classifier algorithms identified participants with impaired thin liquid swallowing safety with a mean AUC of 81.5%, (sensitivity 90.4%, specificity 60.0%). Thicker consistencies were effective for reducing the frequency of penetration-aspiration. This DDS reached targeted performance goals in detecting impaired swallowing safety with thin liquids. Simultaneous measures by DDS and VFSS, as performed here, will be used for future validation studies.

Circulating protein Z concentration, PROZ variants, and unexplained cerebral infarction in young and middle-aged adults.

Protein Z (PZ) is a vitamin K-dependent plasma protein that exhibits both pro- and anticoagulant properties. Both low and high PZ levels have been linked to ischaemic stroke. Although PZ-lowering gene variants have been found to be less common in ischaemic stroke, the relationship remains unclear. We investigated PZ levels and PROZ variants in a multi-ethnic case-control study of unexplained stroke in participants aged 18 to 64. Plasma PZ was measured in cases (≥2 months post-stroke) and controls. PZ polymorphisms G79A (rs3024735) and A13G (2273971) were genotyped. A combined genetic score (0-4 minor alleles) was created assuming additive effects. A total of 715 individuals (1:1.4 cases:controls) was included. Analyses revealed evidence of a non-linear association. After adjusting for demographic and clinical covariates, PZ levels >2.5 µg/ml (90th %ile) were significantly associated with cryptogenic stroke (OR 2.41 [95 % CI 1.34, 4.34]) as compared with lower levels. Higher genetic score was related to progressively lower levels of PZ, and the presence of four minor alleles was associated with lower odds of stroke (adjusted OR 0.26 [95 % CI 0.07, 0.96]) versus 0 minor alleles. In this multi-ethnic study of young and middle-aged adults, there was evidence of a non-linear positive association between PZ level and unexplained stroke, with a directionally consistent association for genetic variants related to PZ levels and cryptogenic stroke. These findings support elevated PZ levels as a risk factor for cryptogenic stroke.

Lipoprotein (a) level, apolipoprotein (a) size, and risk of unexplained ischemic stroke in young and middle-aged adults.

BACKGROUND AND AIMS: Circulating lipoprotein (a) [Lp(a)] level relates inversely to apolipoprotein (a) [apo(a)] size. Both smaller apo(a) isoforms and higher Lp(a) levels have been linked to coronary heart disease and stroke, but their independent contributions are less well defined. We examined the role of Lp(a) in younger adults with cryptogenic stroke. METHODS: Lp(a) and apo(a) isoforms were evaluated in a prospectively designed case-control study of patients with unexplained ischemic stroke and stroke-free controls, ages 18 to 64. Serum Lp(a) was measured among 255 cases and 390 controls with both apo(a)-size independent and dependent assays. Apo(a) size was determined by agarose gel electrophoresis. RESULTS: Cases and controls were similar in socio-demographic characteristics, but cases had more hypertension, diabetes, smoking, and migraine with aura. In race-specific analyses, Lp(a) levels showed positive associations with cryptogenic stroke in whites, but not in the smaller subgroups of blacks and Hispanics. After full adjustment, comparison of the highest versus lowest quartile in whites was significant for apo(a)-size-independent (OR = 2.10 [95% CI = 1.04, 4.27], p = 0.040), and near-significant for apo(a)-size-dependent Lp(a) (OR = 1.81 [95% CI = 0.95, 3.47], p = 0.073). Apo(a) size was not associated with cryptogenic stroke in any race-ethnic subgroup. CONCLUSIONS: This study underscores the importance of Lp(a) level, but not apo(a) size, as an independent risk factor for unexplained ischemic stroke in young and middle-aged white adults. Given the emergence of effective Lp(a)-lowering therapies, these findings support routine testing for Lp(a) in this setting, along with further research to assess the extent to which such therapies improve outcomes in this population.

Quantitative Susceptibility Mapping of Intracerebral Hemorrhages at Various Stages.

PURPOSE: To investigate the magnetic susceptibility of intracerebral hemorrhages (ICH) at various stages by applying quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: Blood susceptibility was measured serially using QSM after venous blood withdrawal from healthy subjects. Forty-two patients who provided written consent were recruited in this Institutional Review Board-approved study. Gradient echo magnetic resonance imaging (MRI) data of the 42 patients (17 females; 64 ± 12 years) with ICH were processed with QSM. The susceptibilities of various blood products within hematomas were measured on QSM. RESULTS: Blood susceptibility continually increased and reached a plateau 96 hours after venous blood withdrawal. Hematomas at all stages were consistently hyperintense on QSM. Susceptibility was 0.57 ± 0.48, 1.30 ± 0.33, 1.14 ± 0.46, 0.40 ± 0.13, and 0.71 ± 0.31 ppm for hyperacute, acute, early subacute, late subacute, and chronic stages of hematomas, respectively. The susceptibility decrease from early subacute (1.14 ppm) to late subacute (0.4 ppm) was significant (P < 0.01). CONCLUSION: QSM reveals positive susceptibility in hyperacute hematomas, indicating that even at their hyperacute stage, deoxyhemoglobin may exist throughout the hematoma volume, not just at its rim, as seen on conventional T2* imaging. QSM also reveals a reduction of susceptibility from early subacute to late subacute ICH, suggesting that methemoglobin concentration decreases at the late subacute stage. J. Magn. Reson. Imaging 2016;44:420-425.

Cerebral venous thrombosis in inflammatory bowel disease.

Cerebral venous thrombosis (CVT) is a rare but devastating complication of inflammatory bowel disease (IBD). Here we describe six IBD patients with cerebral venous thrombosis. The patients presented with hours to days of headache and were found to have venous thrombosis on imaging. Four of the six patients had ulcerative colitis and two had Crohn's disease. All six patients were treated with therapeutic anticoagulation. There were two deaths; one patient became comatose and died despite anticoagulation while the other recovered well from the sinus thrombosis but died after a bowel perforation 3 weeks later. This case series demonstrates the critical need for early recognition of neurological symptoms in patients with IBD during disease flares. It is important to recognize the clinical signs in order to start anticoagulation expeditiously and improve neurological outcomes.

Endovascular therapy for acute stroke in patients with cancer.

Intravenous thrombolysis is the standard treatment for acute ischemic stroke (AIS). However, patients with cancer who have stroke are often precluded from therapy because of coagulopathy or recent surgery. Endovascular therapy may be a more suitable recanalization strategy for some patients with cancer and stroke, but no prior detailed reports documenting its use in this population exist. We present a case series from a tertiary care referral center of 2 patients with active systemic cancer who were successfully treated with endovascular therapy for AIS. Both patients had active lung cancer with excellent premorbid functional status and presented with severe AIS from left middle cerebral artery occlusions. Intravenous thrombolysis was deferred because of absolute contraindications. Mechanical embolectomy was performed instead and revascularization was achieved within 5 hours in both patients, resulting in dramatic neurological recoveries-National Institutes of Health Stroke Scale improved from 14 to 0 and from 23 to 3 from admission to discharge, respectively. In conclusion, endovascular therapy may be beneficial for select patients with cancer and AIS who are ineligible for intravenous thrombolysis. However, further studies are needed to determine the safety and efficacy of endovascular therapy in the population with cancer.

Cerebrovascular reserve and stroke risk in patients with carotid stenosis or occlusion: a systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Impairments in cerebrovascular reserve (CVR) have been variably associated with increased risk of ischemic events and may stratify stroke risk in patients with high-grade internal carotid artery stenosis or occlusion. The purpose of this study is to perform a systematic review and meta-analysis to summarize the association of CVR impairment and stroke risk. METHODS: We performed a literature search evaluating the association of impairments in CVR with future stroke or transient ischemic attack in patients with high-grade internal carotid artery stenosis or occlusion. We included studies with a minimum of 1-year patient follow-up with baseline CVR measures performed by any modality and primary outcome measures of stroke and/or transient ischemic attack. A meta-analysis with assessment of study heterogeneity and publication bias was performed. Results were presented in a forest plot and summarized using a random-effects model. RESULTS: Thirteen studies met the inclusion criteria, representing a total of 1061 independent CVR tests in 991 unique patients with a mean follow-up of 32.7 months. We found a significant positive relationship between impairment of CVR and development of stroke with a pooled random effects OR of 3.86 (95% CI, 1.99-7.48). Subset analysis showed that this association between CVR impairment and future risk of stroke/transient ischemic attack remained significant regardless of ischemic outcome measure, symptomatic or asymptomatic disease, stenosis or occlusion, or CVR testing method. CONCLUSIONS: CVR impairment is strongly associated with increased risk of ischemic events in carotid stenosis or occlusion and may be useful for stroke risk stratification.

Metrics for measuring quality of care in comprehensive stroke centers: detailed follow-up to Brain Attack Coalition comprehensive stroke center recommendations: a statement for healthcare professionals from the American Heart Association/American Stroke Association.

BACKGROUND: Stroke is a major cause of disability and death. The Brain Attack Coalition has proposed establishment of primary and comprehensive stroke centers to provide appropriate care to stroke patients who require basic and more advanced interventions, respectively. Primary stroke centers have been designated by The Joint Commission since 2003, as well as by various states. The designation of comprehensive stroke centers (CSCs) is now being considered. To assist in this process, we propose a set of metrics and related data that CSCs should track to monitor the quality of care that they provide and to facilitate quality improvement. METHODS AND RESULTS: We analyzed available guideline statements, reviews, and other literature to identify the major features that distinguish CSCs from primary stroke centers, drafted a set of metrics and related data elements to measure the key components of these aspects of stroke care, and then revised these through an iterative process to reach a consensus. We propose a set of metrics and related data elements that cover the major aspects of specialized care for patients with ischemic cerebrovascular disease and nontraumatic subarachnoid and intracerebral hemorrhages at CSCs. CONCLUSIONS: The metrics that we propose are intended to provide a framework for standardized data collection at CSCs to facilitate local quality improvement efforts and to allow for analysis of pooled data from different CSCs that may lead to development of national performance standards for CSCs in the future.