Paravascular fluid dynamics reveal arterial stiffness assessed using dynamic diffusion-weighted imaging.

Paravascular cerebrospinal fluid (pCSF) surrounding the cerebral arteries within the glymphatic system is pulsatile and moves in synchrony with the pressure waves of the vessel wall. Whether such pulsatile pCSF can infer pulse wave propagation-a property tightly related to arterial stiffness-is unknown and has never been explored. Our recently developed imaging technique, dynamic diffusion-weighted imaging (dynDWI), captures the pulsatile pCSF dynamics in vivo and can explore this question. In this work, we evaluated the time shifts between pCSF waves and finger pulse waves, where pCSF waves were measured by dynDWI and finger pulse waves were measured by the scanner's built-in finger pulse oximeter. We hypothesized that the time shifts reflect brain-finger pulse wave travel time and are sensitive to arterial stiffness. We applied the framework to 36 participants aged 18-82 years to study the age effect of travel time, as well as its associations with cognitive function within the older participants (N = 15, age > 60 years). Our results revealed a strong and consistent correlation between pCSF pulse and finger pulse (mean CorrCoeff = 0.66), supporting arterial pulsation as a major driver for pCSF dynamics. The time delay between pCSF and finger pulses (TimeDelay) was significantly lower (i.e., faster pulse propagation) with advanced age (Pearson's r = -0.44, p = 0.007). Shorter TimeDelay was further associated with worse cognitive function in the older participants. Overall, our study demonstrated pCSF as a viable pathway for measuring intracranial pulses and encouraged future studies to investigate its relevance with cerebrovascular functions.

Mechanical Thrombectomy Global Access For Stroke (MT-GLASS): A Mission Thrombectomy (MT-2020 Plus) Study.

BACKGROUND: Despite the well-established potent benefit of mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke, access to MT has not been studied globally. We conducted a worldwide survey of countries on 6 continents to define MT access (MTA), the disparities in MTA, and its determinants on a global scale. METHODS: Our survey was conducted in 75 countries through the Mission Thrombectomy 2020+ global network between November 22, 2020, and February 28, 2021. The primary end points were the current annual MTA, MT operator availability, and MT center availability. MTA was defined as the estimated proportion of patients with LVO receiving MT in a given region annually. The availability metrics were defined as ([current MT operators×50/current annual number of estimated thrombectomy-eligible LVOs]×100 = MT operator availability) and ([current MT centers×150/current annual number of estimated thrombectomy-eligible LVOs]×100= MT center availability). The metrics used optimal MT volume per operator as 50 and an optimal MT volume per center as 150. Multivariable-adjusted generalized linear models were used to evaluate factors associated with MTA. RESULTS: We received 887 responses from 67 countries. The median global MTA was 2.79% (interquartile range, 0.70-11.74). MTA was <1.0% for 18 (27%) countries and 0 for 7 (10%) countries. There was a 460-fold disparity between the highest and lowest nonzero MTA regions and low-income countries had 88% lower MTA compared with high-income countries. The global MT operator availability was 16.5% of optimal and the MT center availability was 20.8% of optimal. On multivariable regression, country income level (low or lower-middle versus high: odds ratio, 0.08 [95% CI, 0.04-0.12]), MT operator availability (odds ratio, 3.35 [95% CI, 2.07-5.42]), MT center availability (odds ratio, 2.86 [95% CI, 1.84-4.48]), and presence of prehospital acute stroke bypass protocol (odds ratio, 4.00 [95% CI, 1.70-9.42]) were significantly associated with increased odds of MTA. CONCLUSIONS: Access to MT on a global level is extremely low, with enormous disparities between countries by income level. The significant determinants of MT access are the country's per capita gross national income, prehospital LVO triage policy, and MT operator and center availability.

Risk factors and predictors of intracranial hemorrhage after mechanical thrombectomy in acute ischemic stroke: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR).

BACKGROUND: Reducing intracranial hemorrhage (ICH) can improve patient outcome in acute ischemic stroke (AIS) intervention. We sought to identify ICH risk factors after AIS thrombectomy. METHODS: This is a retrospective review of the Stroke Thrombectomy and Aneurysm Registry (STAR) database. All patients who underwent AIS thrombectomy with available ICH data were included. Multivariable regression models were developed to identify predictors of ICH after thrombectomy. Subgroup analyses were performed stratified by symptom status and European Cooperative Acute Stroke Study (ECASS) grade. RESULTS: The study cohort comprised 6860 patients. Any ICH and symptomatic ICH (sICH) occurred in 25% and 7% of patients, respectively. Hemorrhagic infarction 1 (HI1) occurred in 36%, HI2 in 24%, parenchymal hemorrhage 1 (PH1) in 22%, and PH2 in 17% of patients classified by ECASS grade. Intraprocedural complications independently predicted any ICH (OR 3.8083, P<0.0001), PH1 (OR 1.9053, P=0.0195), and PH2 (OR 2.7347, P=0.0004). Race also independently predicted any ICH (black: OR 0.5180, P=0.0017; Hispanic: OR 0.4615, P=0.0148), sICH (non-white: OR 0.4349, P=0.0107), PH1 (non-white: OR 3.1668, P<0.0001), and PH2 (non-white: OR 1.8689, P=0.0176), with white as the reference. Primary mechanical thrombectomy technique also independently predicted ICH. ADAPT (A Direct Aspiration First Pass Technique) was a negative predictor of sICH (OR 0.2501, P<0.0001), with stent retriever as the reference. CONCLUSIONS: This study identified ICH risk factors after AIS thrombectomy using real-world data. There was a propensity towards a reduced sICH risk with direct aspiration. Procedural complications and ethnicity were predictors congruent between categories of any ICH, sICH, PH1, and PH2. Further investigation of technique and ethnicity effects on ICH and outcomes after AIS thrombectomy is warranted.

Mechanical thrombectomy for large vessel occlusion strokes beyond 24 hours.

BACKGROUND: Recent clinical trials have shown that mechanical thrombectomy is superior to medical management for large vessel occlusion for up to 24 hours from onset. Our objective is to examine the safety and efficacy of thrombectomy beyond the standard of care window. METHODS: A retrospective review was undertaken of the multicenter Stroke Thrombectomy and Aneurysm Registry (STAR). We identified patients who underwent mechanical thrombectomy for large vessel occlusion beyond 24 hours. We selected a matched control group from patients who underwent thrombectomy in the 6-24-hour window. We used functional independence at 3 months as our primary outcome measure. RESULTS: We identified 121 patients who underwent thrombectomy beyond 24 hours and 1824 in the 6-24-hour window. We selected a 2:1 matched group of patients with thrombectomy 6-24 hours as a comparison group. Patients undergoing thrombectomy beyond 24 hours were less likely to be independent at 90 days (18 (18.8%) vs 73 (34.9%), P=0.005). They had higher odds of mortality at 90 days in the adjusted analysis (OR 2.34, P=0.023). Symptomatic intracerebral hemorrhage and other complications were similar in the two groups. In a multivariate analysis only lower number of attempts was associated with good outcomes (OR 0.27, P=0.022). CONCLUSIONS: Mechanical thrombectomy beyond 24 hours appears to be safe and tolerable with no more hemorrhages or complications compared with standard of care thrombectomy. Outcomes and mortality in this time window are worse compared with an earlier time window, but the rates of good outcomes may justify this therapy in selected patients.

Outcomes after endovascular mechanical thrombectomy for low compared to high National Institutes of Health Stroke Scale (NIHSS): A multicenter study.

OBJECTIVE: The role of endovascular mechanical thrombectomy (MT) in patients presenting with "minor" stroke is uncertain. We aimed to compare outcomes after MT for ischemic stroke patients presenting with National Institutes of Health Stroke Scale (NIHSS) 5 and - within the low NIHSS cohort - identify predictors of a favorable outcome, mortality, and symptomatic intracranial hemorrhage (ICH). METHODS: We retrospectively analyzed a prospectively maintained, international, multicenter database. RESULTS: The study cohort comprised a total of 7568 patients from 29 centers. NIHSS was low (<5) in 604 patients (8%), and > 5 in 6964 (92%). Patients with low NIHSS were younger (67 + 14.8 versus 69.6 + 14.7 years, p < 0.001), more likely to have diabetes (31.5% versus 26.9%, p = 0.016), and less likely to have atrial fibrillation (26.6% versus 37.6%, p < 0.001) compared to those with higher NIHSS. Radiographic outcomes (TICI > 2B 84.6% and 84.3%, p = 0.412) and complication rates (8.1% and 7.2%, p = 0.463) were similar between the low and high NIHSS groups, respectively. Clinical outcomes at every follow up interval, including NIHSS at 24 h and discharge, and mRS at discharge and 90 days, were better in the low NIHSS group, however patients in the low NIHSS group experienced a relative decline in NIHSS from admit to discharge. Mortality was lower in the low NIHSS group (10.4% versus 24.5%, p < 0.001). CONCLUSIONS: Relative to patients with high NIHSS, MT is safe and effective for stroke patients with low NIHSS, and it is reasonable to offer it to appropriately selected patients presenting with minor stroke symptoms. Our findings justify efforts towards a randomized trial comparing MT versus medical management for patients with low NIHSS.

Association of Noncontrast Computed Tomography and Perfusion Modalities With Outcomes in Patients Undergoing Late-Window Stroke Thrombectomy.

Importance: There is substantial controversy with regards to the adequacy and use of noncontrast head computed tomography (NCCT) for late-window acute ischemic stroke in selecting candidates for mechanical thrombectomy. Objective: To assess clinical outcomes of patients with acute ischemic stroke presenting in the late window who underwent mechanical thrombectomy stratified by NCCT admission in comparison with selection by CT perfusion (CTP) and diffusion-weighted imaging (DWI). Design, Setting, and Participants: In this multicenter retrospective cohort study, prospectively maintained Stroke Thrombectomy and Aneurysm (STAR) database was used by selecting patients within the late window of acute ischemic stroke and emergent large vessel occlusion from 2013 to 2021. Patients were selected by NCCT, CTP, and DWI. Admission Alberta Stroke Program Early CT Score (ASPECTS) as well as confounding variables were adjusted. Follow-up duration was 90 days. Data were analyzed from November 2021 to March 2022. Exposures: Selection by NCCT, CTP, or DWI. Main Outcomes and Measures: Primary outcome was functional independence (modified Rankin scale 0-2) at 90 days. Results: Among 3356 patients, 733 underwent late-window mechanical thrombectomy. The median (IQR) age was 69 (58-80) years, 392 (53.5%) were female, and 449 (65.1%) were White. A total of 419 were selected with NCCT, 280 with CTP, and 34 with DWI. Mean (IQR) admission ASPECTS were comparable among groups (NCCT, 8 [7-9]; CTP, 8 [7-9]; DWI 8, [7-9]; P = .37). There was no difference in the 90-day rate of functional independence (aOR, 1.00; 95% CI, 0.59-1.71; P = .99) after adjusting for confounders. Symptomatic intracerebral hemorrhage (NCCT, 34 [8.6%]; CTP, 37 [13.5%]; DWI, 3 [9.1%]; P = .12) and mortality (NCCT, 78 [27.4%]; CTP, 38 [21.1%]; DWI, 7 [29.2%]; P = .29) were similar among groups. Conclusions and Relevance: In this cohort study, comparable outcomes were observed in patients in the late window irrespective of neuroimaging selection criteria. Admission NCCT scan may triage emergent large vessel occlusion in the late window.

Prognostic significance of age within the adolescent and young adult acute ischemic stroke population after mechanical thrombectomy: insights from STAR.

OBJECTIVE: Although younger adults have been shown to have better functional outcomes after mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the significance of this relationship in the adolescent and young adult (AYA) population is not well defined given its undefined rarity. Correspondingly, the goal of this study was to determine the prognostic significance of age in this specific demographic following MT for large-vessel occlusions. METHODS: A prospectively maintained international multi-institutional database, STAR (Stroke Thrombectomy and Aneurysm Registry), was reviewed for all patients aged 12-18 (adolescent) and 19-25 (young adult) years. Parameters were compared using chi-square and t-test analyses, and associations were interrogated using regression analyses. RESULTS: Of 7192 patients in the registry, 41 (0.6%) satisfied all criteria, with a mean age of 19.7 ± 3.3 years. The majority were male (59%) and young adults (61%) versus adolescents (39%). The median prestroke modified Rankin Scale (mRS) score was 0 (range 0-2). Strokes were most common in the anterior circulation (88%), with the middle cerebral artery being the most common vessel (59%). The mean onset-to-groin puncture and groin puncture-to-reperfusion times were 327 ± 229 and 52 ± 42 minutes, respectively. The mean number of passes was 2.2 ± 1.2, with 61% of the cohort achieving successful reperfusion. There were only 3 (7%) cases of reocclusion. The median mRS score at 90 days was 2 (range 0-6). Between the adolescent and young adult subgroups, the median mRS score at last follow-up was statistically lower in the adolescent subgroup (1 vs 2, p = 0.03), and older age was significantly associated with a higher mRS at 90 days (coefficient 0.33, p < 0.01). CONCLUSIONS: Although rare, MT for AIS in the AYA demographic is both safe and effective. Even within this relatively young demographic, age remains significantly associated with improved functional outcomes. The implication of age-dependent stroke outcomes after MT within the AYA demographic needs greater validation to develop effective age-specific protocols for long-term care across both pediatric and adult centers.

Middle Cerebral Artery M2 Thrombectomy in the STRATIS Registry.

Background and Purpose: The safety and benefit of mechanical thrombectomy in the treatment of acute ischemic stroke patients with M2 segment middle cerebral artery occlusions remain uncertain. Here, we compare clinical and angiographic outcomes in M2 versus M1 occlusions in the STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) Registry. Methods: The STRATIS Registry was a prospective, multicenter, nonrandomized, observational study of acute ischemic stroke large vessel occlusion patients treated with the Solitaire stent-retriever as the first-choice therapy within 8 hours from symptoms onset. Primary outcome was defined as functional disability at 3 months measured by dichotomized modified Rankin Scale. Secondary outcomes included reperfusion rates and rates of symptomatic intracranial hemorrhage. Results: A total of 984 patients were included, of which 538 (54.7%) had M1 and 170 (17.3%) had M2 occlusions. Baseline demographics were well balanced within the groups, with the exception of mean baseline National Institutes of Health Stroke Scale score which was significantly higher in the M1 population (17.3±5.5 versus 15.7±5.0, P≤0.001). No difference was seen in mean puncture to revascularization times between the cohorts (46.0±27.8 versus 45.1±29.5 minutes, P=0.75). Rates of successful reperfusion (modified Thrombolysis in Cerebral Infarction≥2b) were similar between the groups (91% versus 95%, P=0.09). M2 patients had significantly increased rates of symptomatic ICH at 24 hours (4% versus 1%, P=0.01). Rates of good functional outcome (modified Rankin Scale score of 0­2; 58% versus 59%, P=0.83) and mortality (15% versus 14%, P=0.75) were similar between the 2 groups. There was no difference in the association of outcome and onset to groin puncture or onset to successful reperfusion in M1 and M2 occlusions. Conclusions: In the STRATIS Registry, M2 occlusions achieved similar rates of successful reperfusion, good functional outcome, and mortality, although increased rates of symptomatic ICH were demonstrated when compared with M1 occlusions. The time dependence of benefit was also similar between the 2 groups. Further studies are needed to understand the benefit of mechanical thrombectomy for M2 occlusions. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239640.

Exposure to Neurointervention During Neurology Training.

There is an urgent need to include a dedicated neurointerventional rotation in the curriculum of neurology residency and vascular neurology fellowship based on the paradigm shift in recent years of stroke workflow. The recent changes coupled with growing body of evidence about lack of neurointerventional exposure in current curriculum makes it imperative for us to restructure the training for future neurologists. The exposure will prepare the neurology house-staff for the contemporary management of cerebrovascular diseases and will lead to high quality, patient-centric care.

Spinal subarachnoid hemorrhage secondary to ruptured artery of Adamkiewicz aneurysm: Is conservative management the first best step?

A 43-year-old woman presented to the hospital with severe low back pain and paresthesias in the bilateral lower extremities. MRI of the spine revealed spinal subarachnoid and subdural hemorrhage extending from T11 to L5-S1. A diagnostic spinal angiogram demonstrated a dissecting, partially thrombosed aneurysm of the artery of Adamkiewicz.At four weeks from the sentinel event, her symptoms had completely resolved with resolution on imaging.Isolated artery of Adamkiewicz aneurysms, which are most often dissecting, fusiform aneurysms are extremely rare and management controversial.

Safety and Feasibility of Symptomatic Carotid Artery Stent-Assisted Revascularization within 48 Hours after Symptoms Onset.

OBJECTIVE: We aimed to evaluate the safety and feasibility of carotid artery stenting (CAS) performed in the hyperacute period. METHODS: We analyzed a retrospective database of CAS patients from our center. We included patients with symptomatic isolated ipsilateral extracranial carotid stenosis and acute tandem occlusions who underwent CAS. Hyperacute CAS (HCAS) and acute CAS (ACAS) groups were defined as CAS within 48 hours and >48 hours to 14 days from symptoms onset, respectively. The primary outcome was a composite of any stroke, myocardial infarction, or death at 3 months of follow-up. Secondary outcomes were periprocedural complications and restenosis or occlusion rates. RESULTS: We included 97 patients, 39 with HCAS and 58 with ACAS. There was no significant difference between groups for the primary outcome (HCAS 3.3% vs. ACAS 6.1%; p = 1). There were no differences in the rate of perioperative complications between groups although a trend was observed (HCAS 15.3% vs. ACAS 3.4%; p = .057). The rate of restenosis or occlusion between groups (HCAS 8.1% vs. ACAS 9,1%; log-rank test p = .8) was similar with a median time of follow-up of 13.7 months. CONCLUSION: Based on this study, CAS may be feasible in the hyperacute period. However, there are potential higher rates of perioperative complications in the hyperacute group, primarily occurring in MT patients with acute tandem occlusion. A larger multicenter study may be needed to further corroborate our findings.

Transient global amnesia does not increase the risk of subsequent ischemic stroke: a propensity score-matched analysis.

INTRODUCTION: Data regarding the risk of cerebrovascular events following transient global amnesia (TGA) remain controversial. While some neuroradiological studies suggest an underlying cerebrovascular etiology, results from the clinical studies have been largely conflicting. We, therefore, aimed to evaluate the risk of ischemic stroke in a large, nationally representative sample of patients with TGA. METHODS: We utilized the Nationwide Readmissions Database 2010-2015 to identify all hospitalizations with the primary discharge diagnosis of TGA. We selected a 2% random sample of all elective admissions to be included as controls. A propensity score-matched analysis was performed to match patients with TGA and the controls. The primary outcome was readmission due to ischemic stroke up to 1 year following discharge from the index hospitalization, assessed using the Kaplan-Meier survival analysis in the propensity-matched groups. RESULTS: There were 24,803 weighted hospitalizations due to TGA (mean ± SD age: 65.6 ± 10.4 years, female: 54.9%) and 699,644 corresponding controls. At baseline, patients with TGA were significantly older, more likely to be male, and had a higher prevalence of hypertension, hyperlipidemia, coronary artery disease, cerebrovascular disease, and migraine, as compared to the controls. However, after propensity score matching, we obtained 21,202 cases and 21,293 well-matched corresponding controls, and the risk of readmission due to ischemic stroke in patients with TGA was not different compared to the control group (HR: 1.13, 95% CI 0.62-2.05, P 0.686) during the mean (SD) follow-up period of 192.2 (102.4) days. CONCLUSIONS: After adjustment for demographics and cerebrovascular risk factors, TGA is not associated with an increased risk of subsequent ischemic stroke.

Analysis of Demographic and Educational Backgrounds of Interventional Neuroradiology Fellowship Program Director Workforce in North America.

PURPOSE: To analyse the demographics, academic background, and scholarly activity of Interventional Neuroradiology (INR)/Endovascular Surgical Neuroradiology (ESN) program directors (PDs) in the United States (US) and Canada. METHODS: A list of all INR/ESN fellowships was obtained from the Accreditation Council for Graduate Medical Education, the Committee on Advanced Subspecialty Training, maintained by Society of Neurological Surgeons, the NeuroInterventional Training list website maintained by the Society of NeuroInterventional Surgery, and the Neurosurgical Fellowship Training Program Directory website maintained by the American Association of Neurological Surgeons. Online search was performed to identify PDs for these programs. Publicly available sources used to gather information about each PD included the program websites, the HealthGrades and Doximity websites, and Elsevier's Scopus database. Demographic and educational data including age, gender, educational background, subspecialty, appointment age, interval between residency completion and appointment as PD, additional degrees, academic rank, prior leadership positions, and metrics of scholarly activity were recorded. One-way analysis of variance was used to determine differences between the means of different groups. RESULTS: A total of 78 PDs from 72 programs were included, of which 72 (92.3%) were male with the mean age of 49.59 years (SD 7.25). Specialty division of PDs was neurosurgery (40, 51.3%), radiology (26, 33.3%), and neurology (10, 12.8%), whereas 2 PDs were dual board-certified in neurology and radiology. Twenty-five (32.1%) PDs attended an international medical school. All PDs received an MD degree or foreign equivalent, with no PD holding a DO degree. Eleven PDs received a PhD degree and 16 PDs received fellowship from a professional medical society. The mean ± SD publications, citations, and h-indexes of PDs were 111.32 ± 121.18, 2985.0 ± 1459.0 and 22.27 ± 15.45, respectively. There was no statistical difference in scholarly activity among PDs when stratified on the basis of specialty, gender, and US region. CONCLUSION: INR/ESN PDs are predominantly male, with a majority from neurosurgery background, and thirty percent having graduated from international medical schools.

Risk of Ischemic Stroke after an Inpatient Hospitalization for Transient Ischemic Attack in the United States.

INTRODUCTION: A diagnosis of transient ischemic attack (TIA) must be followed by prompt investigation and rapid initiation of measures to prevent stroke. Prior studies evaluating the risk of stroke after TIA were conducted in the emergency room or clinic settings. Experience of patients admitted to the hospital after a TIA is not well known. We sought to assess the early risk of ischemic stroke after inpatient hospitalization for TIA. METHODS: We used the 2010-2015 Nationwide Readmissions Database to identify all hospitalizations with the primary discharge diagnosis of TIA and investigated the incidence of ischemic stroke readmissions within 90 days of discharge from the index hospitalization. RESULTS: Of 639,569 index TIA admissions discharged alive (mean ± SD age 70.4 ± 14.4 years, 58.7% female), 9,131 (1.4%) were readmitted due to ischemic stroke within 90 days. Male sex, head/neck vessel atherosclerosis, hypertension, diabetes, atrial flutter/fibrillation, previous history of TIA/stroke, illicit drug use, and higher Charlson Comorbidity Index score were independently associated with readmissions due to ischemic stroke. Ischemic stroke readmissions were associated with excess mortality, discharge disposition other than to home, and elevated cost. CONCLUSIONS: Patients hospitalized for TIA have a lower risk of ischemic stroke compared to that reported in the studies based on the emergency room and/or outpatient clinic evaluation. Among these patients, those with cardiovascular comorbidities remain at a higher risk of readmission due to ischemic stroke despite undergoing an inpatient evaluation and should therefore be the target for future preventive strategies.

Safety and efficacy of symptomatic carotid artery stenting performed in an emergency setting.

INTRODUCTION: Carotid artery stenting (CAS) has increasingly emerged as an alternative strategy to carotid endarterectomy in the treatment of patients with symptomatic carotid stenosis. Optimal timing for CAS after symptoms onset remains unclear. We aimed to evaluate the safety and efficacy of CAS when performed in an emergency setting. PATIENTS AND METHODS: We performed a retrospective analysis of CAS patients admitted to our CSC with symptomatic extracranial carotid occlusion or significant stenosis from January 2014-September 2019. Emergency CAS was defined as CAS performed during the same hospitalization from TIA/stroke onset, whereas elective CAS as CAS performed on a subsequent admission. The primary outcome was defined as the occurrence of any stroke, myocardial infarction, or death related to the procedure at 3 months of follow-up. Secondary outcomes included periprocedural complications and the rate of restenosis/occlusion at follow-up. Logistic regression and survival analyses were used to compare outcomes and restenosis at follow-up. RESULTS: We identified 75 emergency and 104 elective CAS patients. Emergency CAS patients had significantly higher rates of ipsilateral carotid occlusion (17% vs. 2%, p < 0.001) and use of general anesthesia (19% vs. 4%, p = 0.001) than elective CAS. There were no significant differences between emergency and elective CAS in the primary (5.7% vs. 1%, p = 0.161) and secondary (9% vs. 4.8%, p = 0.232) outcomes. We did not find differences in the rate of restenosis/occlusion (7% vs. 11.6%; log-rank test p = 0.3) at a median of 13 months follow-up. CONCLUSION: In our study, emergency CAS in symptomatic patients might have a similar safety and efficacy profile to elective CAS at 3 months and long-term follow-up.

Management of Ischemic Stroke Following Left Ventricular Assist Device.

BACKGROUND: Acute ischemic stroke is a common complication and an important source of morbidity and mortality in patients with left ventricular assist devices. There are no standardized protocols to guide management of ischemic stroke among patients with left ventricular assist device. We evaluated our experience treating patients who had an acute ischemic stroke following left ventricular assist device placement. METHODS: We retrospectively reviewed all patients who underwent left ventricular assist device placement from 2010-2019 and identified patients who had acute ischemic stroke following left ventricular assist device placement. RESULTS: Of 216 patients having left ventricular assist device placement (mean±SD age 52.9±16.2 years, women 26.9%), 19 (8.8%) had acute ischemic stroke (mean±SD age 55.8±12.0 years, women 36.8%). Median (interquartile range) time to ischemic stroke following left ventricular assist device placement was 96 (29-461) days. At the time of the ischemic stroke, 16/19 (84.2%) patients were taking both antiplatelet and anticoagulation therapy, 1/19 (5.3%) patient was receiving only anticoagulants, 1/19 (5.3%) patient was taking aspirin and dipyridamole, and 1/19 (5.3%) patient was not taking antithrombic agents. INR was subtherapeutic (INR<2.0) in 7/17 (41.2%) patients. No patient was eligible to receive thrombolytic therapy, while 5/19 (26.3%) underwent mechanical thrombectomy. Anticoagulation was continued in the acute stroke phase in 11/19 (57.9%) patients and temporarily held in 8/19 (42.1%) patients. Hemorrhagic transformation of the ischemic stroke occurred in 6/19 (31.6%) patients. Anticoagulation therapy was continued following ischemic stroke in 4/6 (66.7%) patients with hemorrhagic transformation. CONCLUSIONS: While thrombolytic therapy is frequently contraindicated in the management of acute ischemic stroke following left ventricular assist device, mechanical thrombectomy remains a valid option in eligible patients. Anticoagulation is often continued through the acute phase of ischemic stroke secondary to concerns for LVAD thrombosis. The risks and benefits of continuing anticoagulation must be weighed carefully, especially in patients with large infarct volume, as hemorrhagic transformation remains a common complication.

Differential Risk Factors and Outcomes of Ischemic Stroke due to Cervical Artery Dissection in Young Adults.

INTRODUCTION: Cervical artery dissection (CeAD) is a major cause of ischemic stroke in young adults. Our understanding of the specific risk factors and clinical course of CeAD is still evolving. In this study, we evaluated the differential risk factors and outcomes of CeAD-related strokes among young adults. METHODS: The study population consisted of young patients 15-45 years of age consecutively admitted with acute ischemic stroke to our comprehensive stroke center between January 1, 2010, and November 30, 2016. Diagnosis of CeAD was based on clinical and radiological findings. Univariate and multivariable logistic regression analyses were used to assess the risk factors and clinical outcomes associated with CeAD-related strokes. RESULTS: Of the total 333 patients with acute ischemic stroke included in the study (mean ± SD age: 36.4 ± 7.1 years; women 50.8%), CeAD was identified in 79 (23.7%) patients. As compared to stroke due to other etiologies, patients with CeAD were younger in age, more likely to have history of migraine and recent neck manipulation and were less likely to have hypertension, diabetes, and previous history of stroke. Clinical outcomes of CeAD were comparable to strokes due to other etiologies. Within the CeAD group, higher initial stroke severity and history of tobacco use were associated with higher modified Rankin Scale score at follow-up. CONCLUSIONS: While history of migraine and neck manipulation are significantly associated with CeAD, most of the traditional vascular risk factors for stroke are less prevalent in this group when compared to strokes due to other etiologies. For CeAD-related strokes, higher initial stroke severity and history of tobacco use may be associated with higher stroke-related disability, but overall, patients with CeAD have similar outcomes as compared to strokes due to other etiologies.

Secular Trends for Etiologies of Acute Ischemic Stroke in Young Adults.

BACKGROUND: Ischemic stroke is not rare among young adults. Understanding secular trends in the mechanism of ischemic stroke in young adults may help guide evaluation and secondary prevention. This study compares the mechanism of ischemic stroke and diagnostic studies in two groups of young adults treated at the University of Iowa 20 years apart. METHODS: We retrospectively reviewed all patients aged 15-45 who presented to the University of Iowa Hospitals between 1/2010-11/2016 with ischemic stroke confirmed by imaging. Diagnostic studies and stroke etiologies for each patient using the TOAST criteria were reviewed and compared to a historic sample of young patients of the same age who presented to our center in 1977-1993. RESULTS: We identified 322 young adults, 165 (51.2%) were women. The mean age was 36.3 ± 7.2 years. Vessel imaging was performed in 317 (95.2%) cases vs. 68.9% in the historic sample. Of these, 259 (80.4%) had magnetic resonance angiography (MRA), while diagnostic angiogram was the sole modality used for vessel imaging in the historic sample. Transthoracic echocardiography (TTE) was performed in 101 (31.4%) and transesophageal echocardiography (TEE) was performed in 169 (52.5%) cases compared to 67.1% who underwent TTE in the historic sample. In comparison with the historic sample, there was a significant decline in strokes due to small vessel disease [odds ratio (OR) 0.49, 95% confidence intervals (CI) 0.25-0.97]. The most common etiology of stroke in our sample was cervical artery dissection in 79 (24.5%) patients, whereas this was found in only 6.0% of patients in the historic sample [OR 5.0 and CI (2.99-8.44). CONCLUSIONS: Using the TOAST classification, cryptogenic stroke remained the most common subtype in young adults. While the most common cause for ischemic stroke was cervical artery dissection. DISCLOSURES: Enrique Leira receive salary support from the National Institute of Health.

Tirofiban Protocol Protects Against Delayed Cerebral Ischemia: A Case-Series Study.

BACKGROUND: There has not been any effective prophylaxis for delayed cerebral ischemia delayed cerebral ischemia (DCI) since the introduction of nimodipine. Platelet inhibition may reduce the risk by preventing the formation of microthrombi. Tirofiban has been used as a single monotherapy bridge given its safety profile and controlled platelet inhibition. OBJECTIVE: To assess the risk of DCI in aneurysmal subarachnoid hemorrhages (aSAH) patients treated with the tirofiban protocol. METHODS: aSAH patients between December 2010 and March 2019 who were treated with stent assisted coiling or flow-diverting device were started on a continuous tirofiban infusion protocol and were compared with patients who underwent coil embolization without antiplatelet therapy. Safety analysis was performed to assess DCI, hemorrhagic, and ischemic events. RESULTS: A total of 21 patients were included in the tirofiban series and 81 in the control group. There was no statistical difference in age, gender, Hunt-Hess grade, and Fisher scale between the 2 groups except for a higher Fisher grade II in the tirofiban group. Multivariate analysis revealed tirofiban to reduce the risk of vasospasm by 72 percent (OR .28, P = .03), without affecting the risk of hemorrhagic complications (OR = 0.50, P = .26). Tirofiban reduced the risk of symptomatic stroke endovascular procedure but it did not reach significance (P = .06). DCI, older age, and postprocedural symptomatic stroke were significant predictors of mortality. Tirofiban reduced the mortality risk, but this association was not statistically significant. CONCLUSION: The tirofiban protocol in aSAH patients reduces the risk of DCI without conferring additional risks. This supports previous findings were antiplatelet therapy reduced DCI in human and animal models.

Intracranial Atherosclerosis: A Disease of Functional, not Anatomic Stenosis? How Trans-Stenotic Pressure Gradients Can Help Guide Treatment.

BACKGROUND: Most trials have assessed intracranial atherosclerotic disease (ICAD) severity based on angiographic stenosis. However, anatomic stenosis might not accurately identify the actual state of functional post-stenotic flow limitation. OBJECTIVE: To investigate whether angiographic stenosis correlates with physiologic distal flow limitation, measured as trans-stenotic pressure gradients, in ICAD patients. METHODS: In patients referred for endovascular treatment of anterior circulation symptomatic ICAD who failed maximal medical therapy (MMT) per SAMMPRIS (Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis) criteria, angiographic luminal diameters and percentages of stenosis were correlated with trans-stenotic pressure gradients, calculated as distal/proximal pressure ratios (DPPR) and proximal minus distal pressure gradients (PDPG), by way of Spearman correlation coefficients. RESULTS: Nine patients (3 men, 6 women) were evaluated. Atherosclerotic lesions' locations included internal carotid artery in 5 subjects (2 cavernous, 3 supraclinoid) and proximal middle cerebral artery (M1) in 4 patients. Mean percentage of stenosis was 80 ± 8% (range 75%-94%). Minimal lumen diameter at the most stenotic ICAD site ranged from 0.2 to 0.9 mm (0.59 ± 0.41 mm). DPPR ranged from 0.38 to 0.63 (0.56 ± 0.14). PDPG ranged from 35 to 57 mm Hg (50 ± 8 mm Hg). Spearman coefficients showed no correlation between DPPR or PDPG and angiographic minimal luminal diameters or percentages of stenosis. There were no procedural complications related to trans-stenotic pressure measurements. CONCLUSION: Angiographic stenosis does not reflect the physiologic severity of distal flow limitation in patients with ICAD. Hemodynamic assessment using trans-stenotic pressure ratios and gradients may serve as a more reliable predictive biomarker for MMT failure and response to revascularization.