The volume of steal phenomenon is associated with neurological deterioration in patients with large-vessel occlusion minor stroke not eligible for thrombectomy.

INTRODUCTION: A significant number of patients who present with mild symptoms following large-vessel occlusion acute ischemic stroke (LVO-AIS) are currently considered ineligible for EVT. However, they frequently experience neurological deterioration during hospitalization. This study aimed to investigate the association between neurological deterioration and hemodynamic impairment by assessing steal phenomenon derived from blood oxygenation-level dependent cerebrovascular reactivity (BOLD-CVR) in this specific patient cohort. PATIENTS AND METHODS: From the database of our single-center BOLD-CVR observational cohort study (June 2015-October 2023) we retrospectively identified acute ischemic stroke patients with admission NIHSS < 6, a newly detected large vessel occlusion of the anterior circulation and ineligible for EVT. Neurological deterioration during hospitalization as well as outcome at hospital discharge were rated with NIHSS score. We analyzed the association between these two outcomes and BOLD-CVR-derived steal phenomenon volume through regression analysis. Additionally, we investigated the discriminatory accuracy of steal phenomenon volume for predicting neurological deterioration. RESULTS: Forty patients were included in the final analysis. Neurological deterioration occurred in 35% of patients. In the regression analysis, a strong association between steal phenomenon volume and neurological deterioration (OR 4.80, 95% CI 1.32-31.04, p = 0.04) as well as poorer NIHSS score at hospital discharge (OR 3.73, 95% CI 1.52-10.78, p = 0.007) was found. The discriminatory accuracy of steal phenomenon for neurological deterioration prediction had an AUC of 0.791 (95% CI 0.653-0.930). DISCUSSION: Based on our results we may distinguish two groups of patients with minor stroke currently ineligible for EVT, however, showing hemodynamic impairment and exhibiting neurological deterioration during hospitalization: (1) patients exhibiting steal phenomenon on BOLD-CVR imaging as well as hemodynamic impairment on resting perfusion imaging; (2) patients exhibiting steal phenomenon on BOLD-CVR imaging, however, no relevant hemodynamic impairment on resting perfusion imaging. CONCLUSION: The presence of BOLD-CVR derived steal phenomenon may aid to further study hemodynamic impairment in patients with minor LVO-AIS not eligible for EVT.

Age and Stroke Severity Matter Most for Clinical Outcome in Acute Arteriosclerotic Tandem Lesions.

Background: Tandem lesions (TLs) cause up to 15-30% of all acute ischemic strokes (AISs). Endovascular treatment (EVT) is regarded as the first-line treatment; however, uncertainties remain with respect to the treatment and predictive outcome parameters. Here, we aimed to identify the clinical and demographic factors associated with functional short- and long-term outcomes in AIS patients with arteriosclerotic TLs undergoing EVT. Methods: This was a retrospective, mono-centric cohort study of 116 consecutive AIS patients with arteriosclerotic TLs who were endovascularly treated at a stroke center, with analysis of the relevant demographic, procedural, and imaging data. Results: A total of 116 patients were included in this study, with a median age of 72 years (IQR 63-80), 31% of whom were female (n = 36). The median NIHSS on admission was 14 (IQR 7-19), with a median ASPECT score of 9 (IQR 8-10) and median NASCET score of 99% (IQR 88-100%). A total of 52% of the patients received intravenous thrombolysis. In 77% (n = 89) of the patients, an antegrade EVT approach was used, with a good recanalization (mTICI2b3) achieved in 83% of patients (n = 96). Symptomatic intracerebral hemorrhage occurred in 12.7% (n = 15) of patients. A favorable outcome (mRS0-2) and mortality at 3 months were obtained for 40% (n = 47) and 28% of patients (n = 32), respectively. Age and NIHSS on admission were strongly associated with outcome parameters. Diabetes mellitus and previous neurological disorders were independently associated with long-term mortality (median 11 months, IQR 0-42). Conclusions: Younger age, lower stroke severity, and good recanalization were found to be independently associated with a favorable outcome. In contrast, older age, higher stroke severity, previous neurological disorders, and diabetes were correlated with mortality. The endovascular treatment of acute arteriosclerotic tandem lesions is feasible and relatively safe.

Increased Risk of Recurrent Stroke in Symptomatic Large Vessel Disease With Impaired BOLD Cerebrovascular Reactivity.

BACKGROUND: Impaired cerebrovascular reactivity (CVR) has been correlated with recurrent ischemic stroke. However, for clinical purposes, most CVR techniques are rather complex, time-consuming, and lack validation for quantitative measurements. The recent adaptation of a standardized hypercapnic stimulus in combination with a blood-oxygenation-level-dependent (BOLD) magnetic resonance imaging signal as a surrogate for cerebral blood flow offers a potential universally comparable CVR assessment. We investigated the association between impaired BOLD-CVR and risk for recurrent ischemic events. METHODS: We conducted a retrospective analysis of patients with symptomatic cerebrovascular large vessel disease who had undergone a prospective hypercapnic-challenged BOLD-CVR protocol at a single tertiary stroke referral center between June 2014 and April 2020. These patients were followed up for recurrent acute ischemic events for up to 3 years. BOLD-CVR (%BOLD signal change per mm Hg CO2) was calculated on a voxel-by-voxel basis. Impaired BOLD-CVR of the affected (ipsilateral to the vascular pathology) hemisphere was defined as an average BOLD-CVR, falling 2 SD below the mean BOLD-CVR of the right hemisphere in a healthy age-matched reference cohort (n=20). Using a multivariate Cox proportional hazards model, the association between impaired BOLD-CVR and ischemic stroke recurrence was assessed and Kaplan-Meier survival curves to visualize the acute ischemic stroke event rate. RESULTS: Of 130 eligible patients, 28 experienced recurrent strokes (median, 85 days, interquartile range, 5-166 days). Risk factors associated with an increased recurrent stroke rate included impaired BOLD-CVR, a history of atrial fibrillation, and heart insufficiency. After adjusting for sex, age group, and atrial fibrillation, impaired BOLD-CVR exhibited a hazard ratio of 10.73 (95% CI, 4.14-27.81; P<0.001) for recurrent ischemic stroke. CONCLUSIONS: Among patients with symptomatic cerebrovascular large vessel disease, those exhibiting impaired BOLD-CVR in the affected hemisphere had a 10.7-fold higher risk of recurrent ischemic stroke events compared with individuals with nonimpaired BOLD-CVR.

Toward Individual Treatment in Cervical Artery Dissection: Subgroup Analysis of the TREAT-CAD Randomized Trial.

OBJECTIVE: Uncertainty remains regarding antithrombotic treatment in cervical artery dissection. This analysis aimed to explore whether certain patient profiles influence the effects of different types of antithrombotic treatment. METHODS: This was a post hoc exploratory analysis based on the per-protocol dataset from TREAT-CAD (NCT02046460), a randomized controlled trial comparing aspirin to anticoagulation in patients with cervical artery dissection. We explored the potential effects of distinct patient profiles on outcomes in participants treated with either aspirin or anticoagulation. Profiles included (1) presenting with ischemia (no/yes), (2) occlusion of the dissected artery (no/yes), (3) early versus delayed treatment start (median), and (4) intracranial extension of the dissection (no/yes). Outcomes included clinical (stroke, major hemorrhage, death) and magnetic resonance imaging outcomes (new ischemic or hemorrhagic brain lesions) and were assessed for each subgroup in separate logistic models without adjustment for multiple testing. RESULTS: All 173 (100%) per-protocol participants were eligible for the analyses. Participants without occlusion had decreased odds of events when treated with anticoagulation (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.07-0.86). This effect was more pronounced in participants presenting with cerebral ischemia (n = 118; OR = 0.16, 95% CI = 0.04-0.55). In the latter, those with early treatment (OR = 0.26, 95% CI = 0.07-0.85) or without intracranial extension of the dissection (OR = 0.34, 95% CI = 0.11-0.97) had decreased odds of events when treated with anticoagulation. INTERPRETATION: Anticoagulation might be preferable in patients with cervical artery dissection presenting with ischemia and no occlusion or no intracranial extension of the dissection. These findings need confirmation. ANN NEUROL 2024;95:886-897.

Risk Profiles and Treatment Patterns in Atrial Fibrillation Patients with Chronic Kidney Disease Receiving or not Receiving Anticoagulation Therapy.

Background Patients with atrial fibrillation (AF) and chronic kidney disease (CKD) are at high risk for both thromboembolism and bleeding events. The latter induces a potential reason for withholding oral anticoagulation (OAC) despite an indication for prophylaxis of thromboembolic events. Methods AF patients with CKD (estimated glomerular filtration [eGFR] rate between 15 and 49 mL/min per 1.73 m 2 ) were included in a prospective international registry in Europe between 2016 and 2020, that is, XARENO (factor XA inhibition in renal patients with nonvalvular atrial fibrillation observational registry). The study enrolled adult patients treated at the discretion of physicians with rivaroxaban, vitamin K antagonists (VKA), or without OAC (w/oOAC). Here, we report a prespecified explorative baseline comparison between patients receiving OAC or no OAC within XARENO. Results In total, 1,544 patients (mean age: 78.2 years, mean eGFR: 36.2 mL/min) were studied (rivaroxaban n = 764, VKA n = 691, w/oOAC n = 89). Patients in the w/oOAC group were older and had a similar stroke (mean CHA 2 DS 2 -VASc score 4.0) but higher bleeding risk (mean modified Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly score 2.5 vs. 1.8) compared with the OAC groups. The distribution of comorbidities including hypertension, diabetes, and heart failure was similar. Treatment with antiplatelet drugs was fivefold more frequent in the w/oOAC group. Conclusion Only 5.8% of the overall population of AF patients with advanced CKD received no OAC. These patients were older and had a higher bleeding risk, which might explain this decision, but which contrasts with the more frequent use of antiplatelet drugs in this vulnerable group of patients.

The feasibility of the adapted H-GRASP program for perceived and actual daily-life upper limb activity in the chronic phase post-stroke.

(Purpose: Assessing feasibility and initial impact of the Home-Graded Repetitive Arm Supplementary Program combined with in-home accelerometer-based feedback (AH-GRASP) on perceived and actual daily-life upper limb (UL) activity in stroke survivors during the chronic phase with good UL motor function but low perceived daily-life activity. Material and methods: A 4-week intervention program (4 contact hours, 48 h self-practice) encompassing task-oriented training, behavioral techniques, phone-based support, monitoring, and weekly feedback sessions using wrist-worn accelerometery was implemented using a pre-post double baseline repeated measures design. Feasibility, clinical assessments, patient-reported outcomes, and accelerometer data were investigated. Results: Of the 34 individuals approached, nineteen were included (recruitment rate 56%). Two dropped out, one due to increased UL pain (retention rate 89%). Seven (41%) achieved the prescribed exercise target (120 min/day, six days/week). Positive patient experiences and improvements in UL capacity, self-efficacy, and contribution of the affected UL to overall activity (p < 0.05, small to large effect sizes) were observed. Additionally, seven participants (41%) surpassed the minimal clinically important difference in perceived UL activity.Conclusions: A home-based UL exercise program with accelerometer-based feedback holds promise for enhancing perceived and actual daily-life UL activity for our subgroup of chronic stroke survivors.

Implementing a home-based exercise program with accelerometer-based feedback and telephone supervision may effectively improve upper limb activity after stroke.This program is most suitable for individuals with mild upper limb impairment and should be tailored to their abilities, preferences, and limitations to enhance engagement.The AH-GRASP program shows promising recruitment and retention rates, safety, and positive patient experiences.To improve adherence, consider dividing exercises into shorter sessions that accommodate patient's schedules, attention and endurance levels.

Flow-augmentation STA-MCA bypass for acute and subacute ischemic stroke due to internal carotid artery occlusion and the role of advanced neuroimaging with hemodynamic and flow-measurement in the decision-making: preliminary data.

Background: A major clinical challenge is the adequate identification of patients with acute (<1 week) and subacute (1-6 weeks) ischemic stroke due to internal carotid artery (ICA) occlusion who could benefit from a surgical revascularization after a failure of endovascular and/or medical treatment. Recently, two novel quantitative imaging modalities have been introduced: (I) quantitative magnetic resonance angiography (qMRA) with non-invasive optimal vessel analysis (NOVA) for quantification of blood flow in major cerebral arteries (in mL/min), and (II) blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging to assess cerebrovascular reactivity (CVR). The aim of this study is to present our cohort of patients who underwent surgical revascularization in the acute and subacute phase of ischemic stroke as well as to demonstrate the importance of hemodynamic and flow assessment for the decision-making regarding surgical revascularization in patients with acute and subacute stroke and ICA-occlusion. Methods: Symptomatic patients with acute and subacute ischemic stroke because of persistent ICA-occlusion despite optimal medical/endovascular recanalization therapy who were treated at the Neuroscience Clinical Center of the University Hospital Zurich underwent both BOLD-CVR and qMRA-NOVA to study the hemodynamic and collateral vessel status. Patients selected for surgical revascularization according to our previously published flowchart were included in this prospective cohort study. Repeated NOVA and BOLD-CVR investigations were done after bypass surgery as follow up as well as clinical follow up. Continuous BOLD-CVR and qMRA-NOVA variables were compared using paired Student t-test. Results: Between May 2019 and September 2022, superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery was performed in 12 patients with acute and subacute stroke because of ICA-occlusion despite of optimal endovascular and/or medical treatment prior to the surgery. Impaired BOLD-CVR in the occluded vascular territory [MCA territory: ipsilateral vs. contralateral: -0.03±0.07 vs. 0.11±0.07 %BOLD/mmHgCO2, P<0.001] as well as reduced hemispheric flow with qMRA-NOVA (ipsilateral vs. contralateral: 228.00±54.62 vs. 384.50±70.99 mL/min, P=0.01) were measured indicating insufficient collateralization. Post-operative qMRA-NOVA showed improved hemispheric flow (via bypass) (pre-bypass vs. post-bypass: 236.60±76.45 vs. 334.20±131.33 mL/min, P=0.02) and the 3-month-follow-up with BOLD-CVR showed improved cerebral hemodynamics (MCA territory: pre-bypass vs. post-bypass: -0.01±0.05 vs. 0.06±0.03 %BOLD/mmHgCO2, P=0.02) in all patients studied. Conclusions: Quantitative assessment with BOLD-CVR and qMRA-NOVA allows us to evaluate the pre- and post-operative cerebral hemodynamics and collateral vessel status in patients with acute/subacute stroke due to ICA occlusion who may benefit from surgical revascularization after failure of endovascular/medical treatment.

Movement Reminders to Encourage Arm Use During Daily Life in Stroke Patients.

Stroke is a leading cause of long-term disability, such as loss of upper limb function. Active arm movement and frequent practice are essential to regain such function. Wearable sensors that trigger individualized movement reminders can promote awareness of the affected limb during periods of inactivity. This study investigated the immediate effect of vibrotactile reminders based on activity counts on affected arm use, the evolution of the effect throughout a 6-week intervention at home, and whether the time of the day influences the response to the reminder. Thirteen participants who experienced a unilateral ischemic stroke were included in the analysis. Activity counts were found to increase significantly after receiving a reminder. The immediate effect of receiving a reminder was maintained throughout the day as well as during the study duration of 6 weeks. In conclusion, wearable activity trackers with a feature to trigger individualized vibrotactile reminders could be a promising rehabilitation tool to increase arm activity of the affected side in stroke patients in their home environment.

Blood Oxygenation Level-Dependent Cerebrovascular Reactivity-Derived Steal Phenomenon May Indicate Tissue Reperfusion Failure After Successful Endovascular Thrombectomy.

In acute ischemic stroke due to large-vessel occlusion (LVO), the clinical outcome after endovascular thrombectomy (EVT) is influenced by the extent of autoregulatory hemodynamic impairment, which can be derived from blood oxygenation level-dependent cerebrovascular reactivity (BOLD-CVR). BOLD-CVR imaging identifies brain areas influenced by hemodynamic steal. We sought to investigate the presence of steal phenomenon and its relationship to DWI lesions and clinical deficit in the acute phase of ischemic stroke following successful vessel recanalization.From the prospective longitudinal IMPreST (Interplay of Microcirculation and Plasticity after ischemic Stroke) cohort study, patients with acute ischemic unilateral LVO stroke of the anterior circulation with successful endovascular thrombectomy (EVT; mTICI scale ≥ 2b) and subsequent BOLD-CVR examination were included for this analysis. We analyzed the spatial correlation between brain areas exhibiting BOLD-CVR-associated steal phenomenon and DWI infarct lesion as well as the relationship between steal phenomenon and NIHSS score at hospital discharge.Included patients (n = 21) exhibited steal phenomenon to different extents, whereas there was only a partial spatial overlap with the DWI lesion (median 19%; IQR, 8-59). The volume of steal phenomenon outside the DWI lesion showed a positive correlation with overall DWI lesion volume and was a significant predictor for the NIHSS score at hospital discharge.Patients with acute ischemic unilateral LVO stroke exhibited hemodynamic steal identified by BOLD-CVR after successful EVT. Steal volume was associated with DWI infarct lesion size and with poor clinical outcome at hospital discharge. BOLD-CVR may further aid in better understanding persisting hemodynamic impairment following reperfusion therapy.

High posterior cerebral artery flow predicts ischemia recurrence in patients with internal carotid artery occlusion.

Recurrent stroke is a dreaded complication of symptomatic internal carotid artery occlusion (ICAO). Transcranial Duplex (TCD)-derived increased flow velocity in the ipsilateral posterior cerebral artery (PCA)-P2 segment indicates activated leptomeningeal collateral recruitment and hemodynamic impairment. Leptomeningeal collaterals are pial vascular connections between the anterior and posterior vascular territories. These secondary collateral routes are activated when primary collaterals via the Circle of Willis are insufficient. Our goal was to test the TCD parameter PCA-P2 flow for prediction of ipsilateral ischemia recurrence. We retrospectively analyzed clinical and ultrasound parameters in patients with ICAO. Together with clinical variables, we tested systolic PCA-P2 flow velocity as predictor of a recurrent ischemic event using logistic regression models. Of 111 patients, 13 showed a recurrent ischemic event within the same vascular territory. Increased flow in the ipsilateral PCA-P2 on transcranial ultrasound (median and interquartile range [IQR]: 60 cm/s [IQR 26] vs. 86 cm/s [IQR 41], p = <0.001), as well as previous transient ischemic attack (TIA) and low NIHSS were associated with ischemia recurrence. Combined into one model, accuracy of these parameters to predict recurrent ischemia was 89.2%. Our data suggest that in patients with symptomatic ICAO, flow increases in the ipsilateral PCA-P2 suggest intensified compensatory efforts when other collaterals are insufficient. Together with the clinical variables, this non-invasive and easily assessable duplex parameter detects ICAO patients at particular risk of recurrent ischemia.

Motor rehabilitation after stroke: European Stroke Organisation (ESO) consensus-based definition and guiding framework.

PURPOSE: To propose a consensus-based definition and framework for motor rehabilitation after stroke. METHODS: An expert European working group reviewed the literature, attaining internal consensus after external feedback. FINDINGS: Motor rehabilitation is defined as a process that engages people with stroke to benefit their motor function, activity capacity and performance in daily life. It is necessary for people with residual motor disability whose goal is to enhance their functioning, independence and participation. Motor rehabilitation operates through learning- and use-dependent mechanisms. The trajectory of motor recovery varies across patients and stages of recovery. Early behavioral restitution of motor function depends on spontaneous biological mechanisms. Further improvements in activities of daily living are achieved by compensations. Motor rehabilitation is guided by regular assessment of motor function and activity using consensus-based measures, including patient-reported outcomes. Results are discussed with the patient and their carers to set personal goals. During motor rehabilitation patients learn to optimize and adapt their motor, sensory and cognitive functioning through appropriately dosed repetitive, goal-oriented, progressive, task- and context-specific training. Motor rehabilitation supports people with stroke to maximize health, well-being and quality of life. The framework describes the International Classification of Functioning, Disability and Health in the context of stroke, describes neurobiological mechanisms of behavioral restitution and compensation, and summarizes recommendations for clinical assessment, prediction tools, and motor interventions with strong recommendations from clinical practice guidelines (2016-2022). CONCLUSIONS: This definition and framework may guide clinical educators, inform clinicians on current recommendations and guidelines, and identify gaps in the evidence base.

Resolving the Smoking Paradox: No Evidence for Smoking-Induced Preconditioning in Large Vessel Occlusion Stroke.

INTRODUCTION: Smoking is an established risk factor for stroke. However, several studies have reported a better outcome after stroke for patients who smoke. According to this "smoking paradox" hypothesis, smoking might promote less severe strokes, higher collateral scores, and smaller infarct cores. METHODS: In this retrospective study, we screened data of 2,980 acute ischemic stroke patients with MCA-M1 occlusion treated with mechanical thrombectomy. Patients were categorized according to smoking status (current, former, or never). We assessed univariate associations between clinical characteristics and smoking status. Subsequently, we used adjusted regression analysis to evaluate associations of smoking with stroke severity on admission (National Institutes of Health Stroke Scale [NIHSS]; primary endpoint), infarct core volume, and collateral status (secondary endpoints). RESULTS: Out of 320 patients, 19.7% (n = 63) were current smokers and 18.8% (n = 60) were former smokers. Admission NIHSS, reperfusion success, and modified Rankin Scale (mRS) after 3-6 months were similar in all groups. Current smokers were younger, more often male and less likely to have atrial fibrillation compared to former and never smokers. In regression analyses, smoking status was neither associated with admission NIHSS (estimate 0.54, 95% confidence interval [CI]: -1.27-2.35, p = 0.557) nor with collateral status (estimate 0.79, 95% CI: 0.44-1.44, p = 0.447) or infarct core volume (estimate -0.69, 95% CI: -15.15-13.77, p = 0.925 for current vs. never smokers). CONCLUSION: We could not confirm the smoking paradox. Our results support the fact that smoking causes stroke at a younger age, highlighting the role of smoking as a modifiable vascular risk factor.

Safety and effectiveness of IV Thrombolysis in retinal artery occlusion: A multicenter retrospective cohort study.

BACKGROUND: Retinal artery occlusion (RAO) may lead to irreversible blindness. For acute RAO, intravenous thrombolysis (IVT) can be considered as treatment. However, due to the rarity of RAO, data about IVT safety and effectiveness is limited. METHODS: From the multicenter database ThRombolysis for Ischemic Stroke Patients (TRISP), we retrospectively analyzed visual acuity (VA) at baseline and within 3 months in IVT and non-IVT treated RAO patients. Primary outcome was difference of VA between baseline and follow up (∆VA). Secondary outcomes were rates of visual recovery (defined as improvement of VA ⩾ 0.3 logMAR), and safety (symptomatic intracranial hemorrhage (sICH) according to ECASS II criteria, asymptomatic intracranial hemorrhage (ICH) and major extracranial bleeding). Statistical analysis was performed using parametric tests and a linear regression model adjusted for age, sex and baseline VA. RESULTS: We screened 200 patients with acute RAO and included 47 IVT and 34 non-IVT patients with complete information about recovery of vision. Visual Acuity at follow up significantly improved compared to baseline in IVT patients (∆VA 0.5 ± 0.8, p < 0.001) and non-IVT patients (∆VA 0.40 ± 1.1, p < 0.05). No significant differences in ∆VA and visual recovery rate were found between groups at follow up. Two asymptomatic ICH (4%) and one (2%) major extracranial bleeding (intraocular bleeding) occurred in the IVT group, while no bleeding events were reported in the non-IVT group. CONCLUSION: Our study provides real-life data from the largest cohort of IVT treated RAO patients published so far. While there is no evidence for superiority of IVT compared to conservative treatment, bleeding rates were low. A randomized controlled trial and standardized outcome assessments in RAO patients are justified to assess the net benefit of IVT in RAO.

Impact of age on mechanical thrombectomy and clinical outcome in patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Mechanical thrombectomy is less effective in patients aged 80 years or older. Our goal was to better understand the impact of age in general on recanalization rates and clinical outcome. METHODS: We performed a retrospective analysis of our prospective database of adult patients with acute ischemic stroke due to large vessel occlusions, who had undergone mechanical thrombectomy between 2019 and mid-2021. The cohort was categorized into five age groups: 18 - 49, 50 - 59, 60 - 69, 70 - 79 and ≥ 80 years. Our primary outcome measure was clinical outcome at three months after mechanical thrombectomy, measured by the mRS score. Secondary outcomes were procedure times and rates of successful recanalization, defined by mTICI ≥ 2b. RESULTS: Data of 264 patients were analyzed. There were no significant differences in procedure times (p = 0.46) or in rates of successful recanalization (p = 0.49) between age groups. There was a significant association of age and mRS score at three months (p < 0.0001): From youngest to oldest group, odds of functional independence (mRS ≤ 2) decreased (80.0% vs. 21.3%) and odds of death (mRS 6) increased (13.3% vs. 57.3%). Increasing age was significantly associated with lower rates of functional independence (OR 0.93; [95% CI 0.90 - 0.95]), higher rates of care dependency (OR 1.04; [95% CI 1.01 - 1.07]) and higher mortality rates (OR 1.06; [95% CI 1.04 - 1.09]). CONCLUSION: Higher age had no significant impact on recanalization times or recanalization rates but was strongly associated with worse clinical outcome after mechanical thrombectomy.

Stent reconstruction in intracranial atherosclerotic disease related acute ischemic stroke results in high revascularization rates.

OBJECTIVES: Intracranial atherosclerotic disease (ICAD) is a major cause of large vessel occlusion (LVO) in acute ischemic stroke (AIS). Our study aimed to analyze the effect of percutaneous transluminal angioplasty and stenting (PTAS) in patients with ICAD undergoing rescue treatment in terms of functional outcome and mortality rate at 90 days and compare the results to LVO with thromboembolic origins. MATERIALS AND METHODS: A retrospective review of a mechanical thrombectomy (MT) single center database from 01/2019 to 09/2021 was carried out using chart review and angiogram analysis. From 469 acute stroke patients, 361 patients were enroled in the study, of whom twenty-four (6.6%) were diagnosed with underlying ICAD and treated with angioplasty and stent reconstruction (PTAS) with a standardized medication protocol. Successful reperfusion, peri-procedural complications, and functional independence at 90 days were collected as outcomes. RESULTS: There was no difference in age or admission National Institutes of Health Stroke Scale (NIHSS). Onset to groin puncture (median 460 vs 277 min, P = 0.019) was significantly longer in the ICAD group. The procedure time (median 73 vs 60 min, P = 0.137) did not differ. Successful reperfusion was achieved in 95.8% of ICAD and 91.1% of the remaining patients (P = 0.445). Functional independence (mRS ≤ 2) at 90 days was achieved in 45.8% (11/24) and 42.7% (144/337, (P = 0.767)). The mortality rates (mRS 6) at 90 days were similar (29.2% vs 29.4% (P = 0.983)). CONCLUSION: Despite significantly longer treatment delays, the outcome and revascularization rates of ICAD patients were similar to the thromboembolic cohort. Our proposed protocol of PTAS and medication protocol in ICAD was effective with a similar safety profile as MT in general.

Deep Learning Versus Neurologists: Functional Outcome Prediction in LVO Stroke Patients Undergoing Mechanical Thrombectomy.

BACKGROUND: Despite evolving treatments, functional recovery in patients with large vessel occlusion stroke remains variable and outcome prediction challenging. Can we improve estimation of functional outcome with interpretable deep learning models using clinical and magnetic resonance imaging data? METHODS: In this observational study, we collected data of 222 patients with middle cerebral artery M1 segment occlusion who received mechanical thrombectomy. In a 5-fold cross validation, we evaluated interpretable deep learning models for predicting functional outcome in terms of modified Rankin scale at 3 months using clinical variables, diffusion weighted imaging and perfusion weighted imaging, and a combination thereof. Based on 50 test patients, we compared model performances to those of 5 experienced stroke neurologists. Prediction performance for ordinal (modified Rankin scale score, 0-6) and binary (modified Rankin scale score, 0-2 versus 3-6) functional outcome was assessed using discrimination and calibration measures like area under the receiver operating characteristic curve and accuracy (percentage of correctly classified patients). RESULTS: In the cross validation, the model based on clinical variables and diffusion weighted imaging achieved the highest binary prediction performance (area under the receiver operating characteristic curve, 0.766 [0.727-0.803]). Performance of models using clinical variables or diffusion weighted imaging only was lower. Adding perfusion weighted imaging did not improve outcome prediction. On the test set of 50 patients, binary prediction performance between model (accuracy, 60% [55.4%-64.4%]) and neurologists (accuracy, 60% [55.8%-64.21%]) was similar when using clinical data. However, models significantly outperformed neurologists when imaging data were provided, alone or in combination with clinical variables (accuracy, 72% [67.8%-76%] versus 64% [59.8%-68.4%] with clinical and imaging data). Prediction performance of neurologists with comparable experience varied strongly. CONCLUSIONS: We hypothesize that early prediction of functional outcome in large vessel occlusion stroke patients may be significantly improved if neurologists are supported by interpretable deep learning models.

Cerebral blood flow velocity progressively decreases with increasing levels of verticalization in healthy adults. A cross-sectional study with an observational design.

Background: Autoregulation of the cerebral vasculature keeps brain perfusion stable over a range of systemic mean arterial pressures to ensure brain functioning, e.g., in different body positions. Verticalization, i.e., transfer from lying (0°) to upright (70°), which causes systemic blood pressure drop, would otherwise dramatically lower cerebral perfusion pressure inducing fainting. Understanding cerebral autoregulation is therefore a prerequisite to safe mobilization of patients in therapy. Aim: We measured the impact of verticalization on cerebral blood flow velocity (CBFV) and systemic blood pressure (BP), heart rate (HR) and oxygen saturation in healthy individuals. Methods: We measured CBFV in the middle cerebral artery (MCA) of the dominant hemisphere in 20 subjects using continuous transcranial doppler ultrasound (TCD). Subjects were verticalized at 0°, -5°, 15°, 30°, 45° and 70° for 3-5 min each, using a standardized Sara Combilizer chair. In addition, blood pressure, heart rate and oxygen saturation were continuously monitored. Results: We show that CBFV progressively decreases in the MCA with increasing degrees of verticalization. Systolic and diastolic BP, as well as HR, show a compensatory increase during verticalization. Conclusion: In healthy adults CBFV changes rapidly with changing levels of verticalization. The changes in the circulatory parameters are similar to results regarding classic orthostasis. Registration: ClinicalTrials.gov, identifier: NCT04573114.

Ipsilateral weakness caused by ipsilateral stroke: A case series.

INTRODUCTION: There are few reported cases of ipsilateral weakness following ischemic or hemorrhagic stroke. In these rare cases, ipsilateral weakness is typically the result of damage to uncrossed components of the corticospinal tract (CST) which were recruited in response to previous CST injury. PATIENTS AND METHODS: We report a series of six cases of acute ipsilateral weakness or numbness following a hemorrhagic or ischemic stroke from three medical institutions in Saudi Arabia. RESULTS: Three of these patients presented with right-sided weakness caused by an ipsilateral right hemispheric stroke, while two exhibited left-sided symptoms and one had only left-sided numbness. In all six cases, the ipsilateral corona radiata, internal capsule, basal ganglia, insula, and thalamus were involved. No concomitant opposite hemisphere or brainstem lesion in none of the patients was evident. Two patients had previous strokes affecting the brainstem and left corona radiata, respectively. Complete stroke workup to reveal the cause of stroke was carried out, however no functional MRI was performed. CONCLUSION: Ischemic or hemorrhagic stroke may indeed result in ipsilateral weakness or numbness, though in very rare cases. We assume that the most likely mechanism of their ipsilateral weakness subsequent to the ipsilateral stroke was a functional reorganization favoring CST pathways within the ipsilateral hemisphere.

Stroke-associated infections in patients with and without cancer.

Background: Cancer in stroke patients is associated with higher levels of inflammatory biomarkers and unfavorable poststroke outcomes. We thus explored whether there is a link between cancer and stroke-associated infections. Methods: Medical records of patients with ischemic stroke in 2014-2016 registered in the Swiss Stroke Registry of Zurich were retrospectively analyzed. Incidence, characteristics, treatment, and outcome of stroke-associated infections diagnosed within 7 days after stroke onset were tested for an association with cancer. Results: Among 1181 patients with ischemic stroke, 102 patients with cancer were identified. Stroke-associated infections occurred in 179 and 19 patients (17% and 19%) without and with cancer (P = .60), respectively, among them pneumonia in 95 and 10 patients (9% and 10%) and urinary tract infections in 68 and 9 patients (6% and 9%) (P = .74 and P = .32). Use of antibiotics was similar between groups. Levels of C-reactive protein (CRP) (P < .001), erythrocyte sedimentation rate (ESR) (P = .014) and procalcitonin (P = .015) were higher and levels of albumin (P = .042) and protein (P = .031) were lower in patients with cancer than without cancer. Among patients without cancer, higher CRP (P < .001), ESR (P < .001) and procalcitonin (P = .04) and lower albumin (P < .001) were associated with stroke-associated infections. Among cancer patients with or without infections, no significant differences in these parameters were observed. In-hospital mortality was associated with cancer (P < .001) and with stroke-associated infections (P < .001). However, among patients with stroke-associated infections, cancer was not associated with in-hospital mortality (P = .24) or 30-day mortality (P = .66). Conclusions: Cancer does not represent a risk factor for stroke-associated infections in this patient cohort.

Reinforcement Learning Is Impaired in the Sub-acute Post-stroke Period.

Background: Neurorehabilitation approaches are frequently predicated on motor learning principles. However, much is left to be understood of how different kinds of motor learning are affected by stroke causing hemiparesis. Here we asked if two kinds of motor learning often employed in rehabilitation, (1) reinforcement learning and (2) error-based adaptation, are altered at different times after stroke. Methods: In a cross-sectional design, we compared learning in two groups of patients with stroke, matched for their baseline motor execution deficit on the paretic side. The early group was tested within 3 months following stroke (N = 35) and the late group was tested more than 6 months after stroke (N = 30). Two types of task were studied: one based on reinforcement learning and the other on error-based learning. Results: We found that reinforcement learning was impaired in the early but not the late group, whereas error-based learning was unaffected compared to controls. These findings could not be attributed to differences in baseline execution, cognitive impairment, gender, age, or lesion volume and location. Conclusions: The presence of a specific impairment in reinforcement learning in the first 3 months after stroke has important implications for rehabilitation. It might be necessary to either increase the amount of reinforcement feedback given early or even delay onset of certain forms of rehabilitation training, e.g., like constraint-induced movement therapy, and instead emphasize others forms of motor learning in this early time period. A deeper understanding of stroke-related changes in motor learning capacity has the potential to facilitate the development of new, more precise treatment interventions.