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Background: Intracranial atherosclerosis (ICAS) is a common stroke cause, with a recurrent stroke risk of up to 18% per year despite treatment advances. Although lipid-lowering therapies reduce cardiovascular events, their effect on stroke risk in ICAS remains unclear. Objective: To perform a systematic review and meta-analysis assessing the efficacy of lipid-lowering therapies in improving stroke outcomes among patients with ICAS. Methods: A systematic search of PubMed, Embase, Web of Science, Cochrane, and other databases was conducted from inception to November 2023. Eligible studies compared lipid-lowering therapies (Statins and PCSK9i) to standard care or placebo in patients with ICAS. The primary outcome was the incidence of stroke. Pooled relative risks (RR) with 95% confidence intervals (CI) were calculated using a random-effects model, and forest plots were constructed. Chi-square and I 2 statistics were used to assess heterogeneity. Results: Seven observational studies and two randomized controlled trials involving 1,902 ICAS patients were included. Of these, 801 received lipid-lowering therapy, and 1,101 received standard care or placebo. The weighted mean follow-up was 17.6 months (IQR 9.75-25.5). The weighted mean age was 63.7 years (range 55-68) for the lipid-lowering group and 64.0 years (range 50-66) for controls. Females comprised 42% of both groups. Hypertension was present in 74% of the intervention group and 71% of controls. A history of stroke was reported in 32% of the intervention group and 29% of controls. The weighted mean baseline LDL level was 105 mg/dL in the intervention group and 107 mg/dL in controls. The weighted mean change in LDL pre- and post-treatment in the intervention group was -47.18 mg/dL, compared to -12.39 mg/dL in controls. The incidence of ischemic stroke was 5.0% (40/801) in the lipid-lowering group versus 13.0% (143/1,101) in controls (RR 0.40; 95% CI 0.24-0.64; P<0.001, Figure 1a). Subgroup analysis of studies comparing statin versus no statin treatment showed an RR of 0.40 (95% CI 0.30-0.92; P<0.05, Figure 1b). Another subgroup analysis comparing PCSK9 inhibitors and statins versus statins only found an RR of 0.44; 95% CI 0.20-0.96; P<0.05, Figure 1c). Conclusions: Lipid-lowering therapies significantly reduce the risk of ischemic stroke in patients with intracranial atherosclerosis. The addition of PCSK9 inhibitors to statins appears to provide added stroke risk reduction.

Introduction: Prior data suggest that migraine increases the risk of stroke. However, there is a lack of understanding whether specific migraine features like white matter hyperintensities (WMH) commonly found on brain magnetic resonance (MR) imaging in migraine patients and migraine medications might contribute to Major Adverse Cardiovascular Event (MACE) outcomes including ischemic and hemorrhagic stroke. We assess MACE risk estimation model stratified by event types using Mayo Clinic Electronic Health Record (EHR) data. Methods: Case and control sets, based on MACE occurrence among migraine patients at Mayo Clinic Neurology Department, were propensity matched on age, sex, and MACE risk-factors (atrial fibrillation, diabetes, hyperlipidemia, hypertension, tobacco use) to capture migraine-specific predictors ( Figure 1) . Migraine medications were categorized into 9 classes; Triptans, Ditans, Gepants, Ergots, calcitonin gen-related peptide targeting medications (CGRPs), Beta-blockers, Topiramate, Tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors (SNRIs). Demographics (age and sex), migraine characteristics (chronic migraine, migraine with aura), and presence of WMH on MR imaging were curated. To model non-linear relationship between predictors, two comparative Random Forest (RF) models were evaluated for MACE prediction; i) Model-1: using demographics, migraine characteristics and WMH, ii) Model-2: medications, demographics, migraine characteristics and WMH ( Table 1) . Results: Model-2 outperformed Model-1 indicating combined interaction between medications, WMH, and migraine characteristics for estimating MACE risk. Model-2 achieved AUC of 0.68 for overall MACE, but showed higher performance for ischemic stroke (AUC 0.76). We visualized the effects of input features on ischemic stroke risk for four individual patients using SHAP force plots ( Figure 2 ). The model often considered use of betablockers, chronic migraine, and presence of WMH as factors for increasing ischemic stroke risk. Discussion: Our experiments show that medications, migraine features, WMH and demographics are more effective estimators for ischemic risk stroke risk compared to overall MACE risk, indicating stronger predictive correlation between ischemic stroke and migraine related clinical features. Interestingly, the model inferred the clinical practice pattern of not prescribing Triptans (TRIPTAN=0) to the patients with high risk of stroke from the data itself.

Background: It is known that there are discrepancies between insurance status and access to care for a variety of health conditions. In addition, differences have been shown in initial in-hospital management of stroke as well as outcomes in the acute setting. We sought to examine the relationship between insurance status and risk of recurrent stroke, major bleeding or death following an incident cryptogenic stroke. Methods: Patients with cryptogenic stroke included in a multicenter (n=27 sites) retrospective observational cohort and complete insurance status were evaluated for a primary composite outcome of recurrent stroke, major bleeding, or death. Insurance providers were categorized by Private/Veterans Administration, Medicare, Other, and Medicaid/pending/None, with the primary carrier ranked in that order when multiple insurance carriers applied. Descriptive statistics and an adjusted Cox proportional hazards regression were used to associate the primary insurance provider with the composite outcome, and with each unique secondary outcome, adjusting for age, stroke severity, pre-stroke disability, atherosclerotic risk factors, and potential embolic sources (e.g., patent foramen ovale). Results: Of the 2201 patients, 2006 (91.1%) had reported insurance information and were followed for a median of 1.50 years (interquartile range [IQR 0.41 - 2.99y]). The majority of patients were primary Medicare beneficiaries (42.3%), followed by private insurance (36.7%), Medicaid/none (18.1%) and Other (2.9%). Although there were important differences in demographic and neurodiagnostic results across insurance groups, compared to Private/VA beneficiaries, beneficiaries for Medicaid/pending/none had a higher rate of the composite outcome in adjusted regression (adjusted hazard ratio [HR] 1.35, 95% confidence interval [CI], 1.07-1.69) which was driven largely by the higher rate of recurrent stroke (adjusted HR 1.33, 95%CI, 1.02-1.73) with no significant difference in rate of major bleeding or death (p>0.05 for both). Conclusions: Independent of age, race, pre-existing disability, and atherosclerotic risk factors, insurance status was independently predictive of recurrent stroke in this diverse cohort of cryptogenic stroke.

Introduction: Iatrogenic cervical artery dissection (CeAD) may result from various procedures such as procedural and diagnostic angiography. Due to the rarity of iatrogenic CeAD, existing literature on management and outcomes is limited. This observational cohort study investigates clinical approaches and long-term outcomes of iatrogenic CeAD after endovascular interventions. Methods: We conducted a retrospective chart review to analyze patients who underwent endovascular treatments at the Mayo Clinic from 1998 to 2021. We focused on patients with iatrogenic CeAD resulting from interventions. Pertinent patient factors were extracted. Descriptive statistics highlighted the relationship between treatments and long-term clinical outcomes. Results: Between 1998 and 2021, 21,191 patients underwent catheter cerebral angiography. Among them, 32 had iatrogenic CeAD (30 identified as white, 23 women, median age 59 [range 40.5–92.9]). Common comorbidities included hypertension (62.5%), smoking (56.3%), and hyperlipidemia (46.9%). Of the 32 patients, 9(28.1%) had dissection with diagnostic angiograms, 6(18.8%) endovascular thrombectomy, 15(46.9%) aneurysm treatment, and 2(6.3%) angioplasty with or without stenting. The location of dissections was dependent upon the intervention: 17(53.1%) had internal carotid artery dissection, 13(40.6%) vertebral artery dissection, and 2(6.3%) common carotid dissection. One patient was symptomatic with neck pain. All dissections were diagnosed by cerebral angiography during the same session as the initial intervention. Only 4(12.5%) were treated with hyperacute stenting. Following diagnosis, 30(93.7%) were placed on antithrombotic therapy, including aspirin alone (34.4%) or dual antiplatelet therapy with aspirin and clopidogrel (37.5%). The median duration of acute treatment was 3 months. The median duration of imaging follow up was 1022 days. Follow-up imaging showed an excellent radiological course, with complete or nearly complete dissection remodeling. Conclusions: Iatrogenic CeAD with endovascular interventions is rare and typically benign. Most cases are managed medically without significant clinical complications or long-term negative outcomes. Single or dual antiplatelet therapies remain preferred treatments, in line with current trends. Key factors influencing clinical decision-making include location, occlusion rate, pseudoaneurysm formation, intracranial extension, distal collateral circulation, and ischemia.

Introduction: Mechanical thrombectomy (MT) is a primary treatment for acute ischemic stroke due to large vessel occlusions. While effective, 20-40% of patients experience hemorrhagic transformation (HT), and around 50% fail to achieve favorable functional outcomes. Transcranial Doppler (TCD) is a non-invasive and cost-effective method for real-time monitoring of hemodynamic status following MT. However, the prognostic value of TCD parameters in predicting HT and poor functional outcome is unclear. We performed a systematic review and meta-analysis of 4 TCD parameters (mean flow velocity (MFV), MFV index, peak systolic velocity (PSV), and pulsatility index (PI) in patients with and without HT and favorable vs poor functional recovery (modified Rankin Scale (mRS) 0-2 vs 3-6). Methods: PubMed, Embase, and Scopus were searched on July 25, 2024 to identify observational studies in which TCD parameters were measured within 48 hours from successful MT (Thrombolysis in Cerebral Infarction 2b–3) of anterior circulation. Risk of bias assessment was performed using a standardized tool tailored for TCD studies. The standardized mean difference (Hedges’ g) with 95% CI and risk ratios (RRs) with 95% CI were calculated using random-effects models. The review was prospectively registered on PROSPERO (registration number CRD42024575381). Results: Eleven studies met inclusion criteria. No study had high risk of bias. MFV and MFV index were higher in patients with HT+ compared with HT- (Hedges' g = 0.42 and 0.54, p = 0.015 and 0.005, respectively). Patients with MFV index ≥1.3 showed a higher risk of all HT (RR = 2.01, 95% CI = 1.27–3.17, p = 0.003), symptomatic HT (RR, 4.68; 95% CI,1.49–14.65, p=0.008), and poor functional recovery at 90 days (RR, 1.66; 95% CI,1.32–2.08, p<0.001), respectively. There was no difference in mean PSV (p=0.1) and PI (p=0.3) among groups with and without HT. Conclusion: Our study highlights the prognostic value of TCD parameters, particularly MFV index, in predicting HT, symptomatic HT, and poor functional recovery after successful MT in the anterior circulation. Our findings were limited by low number of studies. Large-scale and multi-center studies are needed to confirm these findings and validate the MFV index as a reliable predictor to improve post-thrombectomy care.

Background: Symptomatic intracranial hemorrhage (sICH) is the most dreaded complication after reperfusion therapy for acute ischemic stroke. We performed a meta-analysis of randomized controlled trials to estimate and compare risks of sICH after mechanical thrombectomy (MT) depending on the location of the large vessel occlusion, concomitant use of intravenous thrombolysis, timing of treatment, and core size. Methods: Randomized controlled trials were included following a comprehensive search strategy on different databases from inception to March 1, 2024. Random-effect models in a meta-analysis were employed to get the pooled risk ratios (RRs) and their corresponding 95% confidence intervals (95% CI) for sICH with MT, compared to other reperfusion treatment regimens, including best medical treatment and intravenous thrombolysis (IVT). Results: MT in the anterior circulation was associated with a significantly higher risk of sICH as compared with no-MT (RR: 1.46; 95%CI: 1.03-2.07; P = 0.037). Risk of sICH was comparable between the MT and MT+IVT groups (RR: 0.77; 95%CI: 0.57-1.03; P = 0.079). There was no difference in sICH risk with MT as compared with no-MT within 6 hours of last known well (RR: 1.14; 95%CI: 0.78-1.66; P = 0.485) and beyond that time (RR: 1.29; 95%CI: 0.80-2.08; P = 0.252); the risk of sICH was also comparable between MT conducted within 6 hours of last known well and MT conducted beyond that time (P = 0.512). The sICH risk for MT in the posterior circulation (RR: 7.48; 95%CI: 2.27-24.61) was significantly higher than for MT in the anterior circulation (RR: 1.18; 95%CI: 0.90-1.56) (P = 0.003). MT was also associated with a significantly higher sICH risk than no-MT among patients with large-core strokes (RR: 1.71; 95%CI: 1.09-2.66, P = 0.018). Conclusion: When evaluating cumulative evidence from randomized controlled trials, the risk of sICH is increased after MT compared with patients not treated with MT. Yet, the difference is largely driven by the greater risk of sICH in patients treated with MT for posterior circulation occlusions and, to a lesser degree, large core strokes. Concomitant use of intravenous thrombolysis and the use of MT in the extended therapeutic window do not raise the risk of sICH.

Introduction: Patients with atherosclerotic carotid artery disease are at high risk of mortality in the long-term follow-up after carotid endarterectomy (CEA), partly due to dysrhythmia. Atrial fibrillation (AF) is a common cardiac dysrhythmia linked to stroke and cardiovascular events. An artificial intelligence-based electrocardiogram (ECG) AF algorithm (AI-AF) can effectively identify silent AF. We aimed to assess the effectiveness of AI-AF in predicting mortality in patients with carotid artery disease undergoing CEA. Methods: Patients with carotid artery disease undergoing CEA at Mayo Clinic from 2002-2023 were included if they had >30 days follow-up and an ECG within one year before CEA. The ECG closest to the CEA date was used to calculate AI-AF (probability of AF ranging from 0 to 1). All-cause mortality rates after CEA were obtained from clinical records. The optimal AI-AF cut-off value for predicting mortality was calculated using a receiver operating characteristic curve and the Youden index. Long-term survival after CEA was depicted with a Kaplan Meier plot and compared with the Log-rank test. Univariate and multivariate Cox Regression models were used to assess the predictive value of AI-AF for mortality, adjusting for age, sex, body mass index, diabetes mellitus, hypertension, and hyperlipidemia. Results: A total of 636 patients with a median age of 72 [IQR: 66, 78] years and 414 (65.1%) males were included. The median AI-AF was 0.056 [IQR: <0, 0.171]. Over a median follow-up time of 7.1 [IQR: 2.7, 11.5] years, mortality occurred in 326 (51.3%) patients. AI-AF significantly predicted mortality in univariate and multivariate Cox regression analysis (HR: 3.47, 95%CI: 2.34-5.16, P<0.001; HR: 2.30, 95%CI: 1.44-3.68, P<0.001, respectively). The best cut-off value for AI-AF for mortality prediction was 0.025 (area under the curve: 0.608). High and low AI-AF were defined as AI-AF≥ 0.025 and <0.025, respectively. Mortality was significantly higher in high AI-AF compared to low AI-AF patients (P<0.001, Figure 1A,1B), and high AI-AF was a significant predictor of mortality (univariate: Figure 2; multivariate Cox regression: HR: 2.11, 95%CI: 1.56-2.84, P<0.001). Conclusion: AI-AF can identify patients with a higher risk of mortality after CEA. This finding supports a role for AI algorithms in risk stratification of patients with carotid artery disease following CEA. Future studies are needed to elucidate the contribution of AF to all-cause mortality.

Background: Carotid stenosis has been associated with stroke and cognitive impairment. It remains unclear if hypometablism, a marker for neurodegeneration, may be in the mechanistic pathway in the association between carotid stenosis and cognitive decline. This study aims to investigate whether patients with carotid stenosis exhibit reduced cerebral glucose metabolism, using 18-FDG PET imaging as a sensitive measure of brain’s glucose metabolism. Methods: We have identified 138 patients from one health care system who underwent 18-FDG PET imaging and had extracranial carotid imaging (doppler ultrasound/CT angiography/MR angiography) within 1 year of PET scan. Severity of carotid stenosis was defined using NASCET criteria as <50% (mild), 50-69% (moderate), >70% (high-grade). Cerebral glucose metabolism was quantified by measuring standardized uptake value ratio (SUVR) after normalizing to pons in 12 different regions of interest (ROI). Hypometabolism was defined using the cutoff of SUVR <1.41. SUVR and hypometabolism measures were compared across severity of carotid stenosis. Results: Of 138 patients identified, 54 were excluded due to indeterminant ipsilateral hemisphere status. Mild, moderate and severe stenosis was present in 86.9%, 4.8%, 8.3%, respectively. The analysis revealed a numerically reduced cerebral glucose metabolism in patients with moderate to severe carotid stenosis compared to control subjects (Table 1). The most pronounced decrease in FDG uptake was observed in regions supplied by the affected carotid artery, particularly the ipsilateral cortical areas. There was a numerically increased risk of hypometabolism with increasing carotid stenosis: Adjusted odds of hypometabolism ipsilateral to the carotid stenosis were 2.90, 5.56 across patients with moderate and high-grade carotid stenosis in sensorimotor cortex (trend-P=0.095). These findings were consistent across different regions supplied by the stenotic carotid artery but attenuated in territories supplied by unaffected posterior arteries (Table 2). Conclusions: FDG-PET imaging demonstrates reduced glucose metabolism in patients with carotid stenosis, suggesting that cerebral hypoperfusion may contribute to the metabolic disturbances observed in these patients. These results underscore the importance of early detection and management of carotid stenosis to mitigate potential cerebral metabolic deficits and the associated risk of dementia and ischemic stroke.

Background: Left ventricular (LV) injury is a cardioembolic etiology of ischemic stroke. We aimed to 1) evaluate recurrent stroke risk among patients with cryptogenic stroke and LV injury, and 2) determine if there is a treatment effect with anticoagulation in this population. Methods: We analyzed the multicenter, retrospective Cardiac Abnormalities in Stroke Prevention and Recurrence cohort of patients with cryptogenic ischemic stroke. The exposure was LV injury defined by 1) LV ejection fraction (EF) 20-40% and/or 2) LV wall motion abnormality (hypokinesis or akinesis). The primary composite outcome included recurrent stroke, major bleeding, or death. Cox proportional hazard models were built and sequentially adjusted for 1) age and sex (Model 1), and 2) age, sex, race, ethnicity, anti-thrombotic use, and vascular risk factors (Model 2). We then assessed if there was heterogeneity in treatment effect by LV injury status with an interaction term of LV injury and oral anticoagulation use in Model 2. Results: Of 2,641 patients in CASPR, the analytic cohort included 2,191 patients with complete exposure and outcome data (median age 65 years, 49.8% female, median follow-up 1.55 years). There were 113 (5.2%) patients with LV injury (median LVEF 30%, interquartile range 25-34%). There were 559 incident events (321 recurrent strokes [288 ischemic], 71 major hemorrhages, 250 deaths). Among patients with LV injury, 15.9% were prescribed an anticoagulant within 7 days of index stroke (vs 9.6% without LV injury, p=0.03). The unadjusted risk of the primary outcome was non-significantly higher among patients with LV injury vs without (HR 1.40; 95% confidence interval [CI], 0.98-2.00), but became significant in Model 1 (HR 1.50; 95% CI, 1.21-1.85) and in Model 2 (HR 1.35, 95% CI, 1.11-1.64). In the LV injury subgroup, anticoagulation vs antiplatelet therapy was associated with a significant reduction in the primary outcome (HR 0.63, 95% CI, 0.43-0.94). In patients without LV injury, anticoagulation was associated with a higher risk of the composite outcome (HR 4.35, 95% CI, 1.69-11.16, p[interaction]=0.002). Conclusion: In this observational study, there was an increased risk of the primary outcome which included recurrent stroke among patients with cryptogenic stroke and LV injury. Anticoagulation use in LV injury is associated with a significant reduction in the risk of the primary outcome. These findings warrant confirmation in a dedicated randomized controlled trial.

Background: High adherence to the Mediterranean Diet (MeDi) was associated with better cognitive performance and decreased memory decline among Hispanic or Latino adults. Objective: Investigate if higher adherence to the MeDi improves white matter (WM) integrity among Hispanic/Latino adults and if this effect is mediated by cardiovascular health (CVH). Methods: We included 2,774 participants from the Study of Latinos-Investigation of Neurocognitive Aging-MRI Ancillary Study. Participants completed 24-hour dietary recalls at baseline (2008-2011) which were used to calculate a MeDi score (MeDiS, range 0-9). Brain MRI and diffusion tensor images were collected between 2018 and 2022 on a 3T MRI scanner using a standardized protocol. WM integrity was ascertained using WM hyperintensity (WMH) volume and fractional anisotropy (FA). WMH volumes were residualized for total cranial volume and Ln-transformed prior to analysis. The association of MRI outcomes with MeDiS and its components was investigated using weighted linear regression analysis with complex survey design adjusting for age, sex, sociodemographic characteristics. Cardiovascular health was assessed using the Life’s Simple 7 (LS7, range 0-14) score. The mediating effect of LS7 on the primary outcome was reported as Average Causal Mediation Effects (ACME) and Average Direct Effects (ADE). Statistical significance was set at p<0.05. Results: Mean age (95% CI) at MRI scan was 64.0 (63.4 to 65.2) and 44% were males. Mean MeDiS was 5.01 (4.89 to 5.12) and LS7 was 7.1 (7.0 to 7.3). In our fully adjusted model, increasing MeDi adherence was associated with decreased LnWMH volume (β=-0.07, 95% CI -0.10 to -0.03) and increased FA (β=0.002, 95% CI 0.001 to 0.003). Increasing LS7 scores partially mediated the relationship between MeDiS and WMHs (ACME=-0.01, ADE=-0.08, p<0.05, percent mediation=9%) and between MeDiS and FA (ACME=0.0001, ADE=0.002, p<0.01, percent mediated=8%). Among the different MeDi components, consumption of whole grains and fish above sex-specific energy adjusted energy median intake predicted lower WMH volume and increase FA (p<0.05 for both). Conclusions: Among diverse Hispanic/Latino adults, high MeDi adherence was associated with preserved WM integrity. This association was partially mediated by CVH. This suggests that the beneficial effect of MeDi on brain health is not fully explained by vascular risk factors. A culturally tailored MeDi may preserve brain health among Hispanic/Latino adults.