Updates on Prevention of Hemorrhagic and Lacunar Strokes

Cognitive impairment in cerebral small vessel disease induced by hypertension

ABSTRACT

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease, the most common cerebrovascular disease. However, the causal relationship between hypertension and cerebral small vessel disease remains unclear. Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease. Chronic hypertension and lifestyle factors are associated with risks for stroke and dementia, and cerebral small vessel disease can cause dementia and stroke. Hypertension is the main driver of cerebral small vessel disease, which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction, leukoaraiosis, white matter lesions, and intracerebral hemorrhage, ultimately resulting in cognitive decline and demonstrating that the brain is the target organ of hypertension. This review updates our understanding of the pathogenesis of hypertension-induced cerebral small vessel disease and the resulting changes in brain structure and function and declines in cognitive ability. We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

Differential risk factor profile and neuroimaging markers of small vessel disease between lacunar ischemic stroke and deep intracerebral hemorrhage

Background

Lacunar ischemic stroke (LIS) and deep intracerebral hemorrhage (dICH) are two stroke phenotypes of deep perforator arteriopathy. It is unclear what factors predispose individuals with deep perforator arteriopathy to either ischemic or hemorrhagic events.

Objectives

We aimed to investigate risk factors and neuroimaging features of small vessel disease (SVD) associated with LIS versus dICH in a cross-sectional study.

Methods

We included patients with clinically presenting, magnetic resonance imaging-confirmed LIS or dICH from two tertiary hospitals between 2010 and 2021. We recorded vascular risk factors and SVD markers, including lacunes, white matter hyperintensities (WMH), perivascular spaces (PVS), and cerebral microbleeds (CMB). Logistic regression modeling was used to determine the association between vascular risk factors, SVD markers, and stroke phenotype. We further created WMH probability maps to compare WMH distribution between LIS and dICH.

Results

A total of 834 patients with LIS (mean age 61.7 ± 12.1 years) and 405 with dICH (57.7 ± 13.2 years) were included. Hypertension was equally frequent between LIS and dICH (72.3% versus 74.8%, p = 0.349). Diabetes mellitus, hyperlipidemia, smoking, and prior ischemic stroke were more associated with LIS [odds ratio (OR) (95% confidence interval (CI)), 0.35 (0.25-0.48), 0.32 (0.22-0.44), 0.31 (0.22-0.44), and 0.38 (0.18-0.75)]. Alcohol intake and prior ICH were more associated with dICH [OR (95% CI), 2.34 (1.68-3.28), 2.53 (1.31-4.92)]. Lacunes were more prevalent in LIS [OR (95% CI) 0.23 (0.11-0.43)], while moderate-to-severe basal-ganglia PVS and CMB were more prevalent in dICH [OR (95% CI) 2.63 (1.35-5.27), 4.95 (2.71-9.42)]. WMH burden and spatial distribution did not differ between groups.

Conclusion

The microangiopathy underlying LIS and dICH reflects distinct risk profiles and SVD features, hence possibly SVD subtype susceptibility. Prospective studies with careful phenotyping and genetics are needed to clarify the mechanisms underlying this difference.

Novel inflammatory and insulin resistance indices provide a clue in cerebral amyloid angiopathy

This study investigated the correlation of newly identified inflammatory and insulin resistance indices with cerebral amyloid angiopathy (CAA), and explored their potential to differentiate CAA from hypertensive arteriopathy (HA). We retrospectively analyzed 514 consecutive patients with cerebral small vessel disease (CSVD)-related haemorrhage, comparing the differences in novel inflammatory and insulin resistance indices between patients with CAA and HA. Univariate regression, LASSO and multivariate regression were used to screen variables and construct a classification diagnosis nomogram. Additionally, these biomarkers were explored in patients with mixed haemorrhagic CSVD. Inflammatory indices were higher in CAA patients, whereas insulin resistance indices were higher in HA patients. Further analysis identified neutrophil-to-lymphocyte ratio (NLR, OR 1.17, 95% CI 1.07-1.30, P < 0.001), and triglyceride-glucose index (TyG, OR = 0.56, 95% CI 0.36-0.83, P = 0.005) as independent factors for CAA. Therefore, we constructed a CAA prediction nomogram without haemorrhagic imaging markers. The nomogram yielded an area under the curve (AUC) of 0.811 (95% CI 0.764-0.865) in the training set and 0.830 (95% CI 0.718-0.887) in the test set, indicating an ability to identify high-risk CAA patients. These results show that CSVD patients can be phenotyped using novel inflammatory and insulin resistance indices, potentially allowing identification of high-risk CAA patients without haemorrhagic imaging markers.

Aldosteronism is associated with more severe cerebral small vessel disease in hypertensive intracerebral hemorrhage

Primary aldosteronism is associated with various types of cardiovascular and cerebrovascular damage independently of hypertension. Although chronic hypertension and related cerebral arteriosclerosis are the main risk factors for intracerebral hemorrhage, the effects of aldosteronism remain poorly understood. We enrolled 90 survivors of hypertensive intracerebral hemorrhage, 21 of them with aldosteronism and 69 with essential hypertension as controls in this study. Clinical parameters and neuroimaging markers of cerebral small vessel disease were recorded, and its correlations with aldosteronism were investigated. Our results showed that the aldosteronism group (55.2 ± 9.7 years, male 47.6%) had similar hypertension severity but exhibited a higher cerebral microbleed count (interquartile range) (8.5 [2.0‒25.8] vs 3 [1.0‒6.0], P = 0.005) and higher severity of dilated perivascular space in the basal ganglia (severe perivascular space [number >20], 52.4% vs. 24.6%, P = 0.029; large perivascular space [>3 mm], 52.4% vs. 20.3%, P = 0.010), compared to those with essential hypertension (53.8 ± 11.7 years, male 73.9%). In multivariate models, aldosteronism remained an independent predictor of a higher (>10) microbleed count (odds ratio = 8.60, P = 0.004), severe perivascular space (odds ratio = 4.00, P = 0.038); the aldosterone-to-renin ratio was associated with dilated perivascular space (P = 0.043) and large perivascular space (P = 0.008). In conclusions, survivors of intracerebral hemorrhage with aldosteronism showed a tendency towards more severe hypertensive arteriopathy than the essential hypertension counterparts independently of blood pressure; aldosteronism may contribute to dilated perivascular space around the deep perforating arteries. Aldosteronism is associated with more severe cerebral small vessel disease in hypertensive intracerebral hemorrhage.

Differences in lobar microbleed topography in cerebral amyloid angiopathy and hypertensive arteriopathy

Lobar cerebral microbleeds are a characteristic neuroimaging finding in cerebral amyloid angiopathy (CAA) but can also be found in hypertensive arteriolosclerosis. We aimed to investigate whether CAA is more associated with intracortical lobar microbleeds than hypertensive arteriosclerosis. Ninety-one survivors of spontaneous intracerebral hemorrhage with at least one lobar microbleed were included and underwent brain MRI and amyloid PET. We categorized lobar microbleeds as intracortical, juxtacortical, or subcortical. We assessed the associations between the lobar microbleed categories and microangiopathy subtypes or cerebral amyloid load based on the Pittsburgh Compound-B PET standardized uptake value ratio (SUVR). Patients with CAA had a higher prevalence of intracortical lobar microbleeds (80.0% vs. 50.8%, P = 0.011) and lower prevalence of subcortical lobar microbleeds (13.3% vs. 60.1%, P < 0.001) than patients with hypertensive arteriolosclerosis. Strictly intracortical/juxtacortical lobar microbleeds were associated with CAA (OR 18.9 [1.9-191.4], P = 0.013), while the presence of subcortical lobar microbleeds was associated with hypertensive arteriolosclerosis (OR 10.9 [1.8-68.1], P = 0.010). Amyloid retention was higher in patients with strictly intracortical/juxtacortical CMBs than those without (SUVR = 1.15 [1.05-1.52] vs. 1.08 [1.02-1.19], P = 0.039). Amyloid retention positively correlated with the number of intracortical lobar microbleeds (P < 0.001) and negatively correlated with the number of subcortical lobar microbleeds (P = 0.018). CAA and cortical amyloid deposition are more strongly associated with strictly intracortical/juxtacortical microbleeds than subcortical lobar microbleeds. Categorization of lobar microbleeds based on anatomical location may help differentiate the underlying microangiopathy and potentially improve the accuracy of current neuroimaging criteria for cerebral small vessel disease.

Stroke Prevention in Atrial Fibrillation: Our Current Failures and Required Research

Nonvalvular atrial fibrillation is a common rhythm disorder of middle-aged to older adults that can cause ischemic strokes and systemic embolism. Lifelong use of oral anticoagulants reduces the risk of these ischemic events but increases the risk of major and clinically relevant hemorrhages. These medications also require strict compliance for efficacy, and they have nontrivial failure rates in higher-risk patients. Left atrial appendage closure is a nonpharmacological method to prevent ischemic strokes in atrial fibrillation without the need for lifelong anticoagulant use, but this procedure has the potential for complications and residual embolic events. This workshop of the Roundtable of Academia and Industry for Stroke Prevention discussed future research needed to further decrease the ischemic and hemorrhagic risks among patients with atrial fibrillation. A direct thrombin inhibitor, factor Xa inhibitors, and left atrial appendage closure are FDA-approved approaches whereas factor XIa inhibitors are currently being studied in phase 3 randomized controlled trials for stroke prevention. The benefits, risks, and shortcomings of these treatments and future research required in different high-risk patient populations are reviewed in this consensus statement.

Implication of Cerebral Small-Vessel Disease on Perihematomal Edema Progress in Patients With Hypertensive Intracerebral Hemorrhage

BACKGROUND

Perihematomal edema (PHE) is an important determinant of outcome in spontaneous intracerebral hemorrhage (ICH) due to cerebral small vessel disease (CSVD). However, it is not known to date whether the severity of CSVD is associated with the extent of PHE progression in the acute phase.

PURPOSE

To investigate the association between the magnetic resonance imaging (MRI) marker of severe chronic-ischemia cerebral small vessel changes (sciSVC) and PHE growth or hematoma absorption among ICH patients with hypertension.

STUDY TYPE

Retrospective.

POPULATION

Three hundred and sixty-eight consecutive hypertensive ICH patients without surgical treatment.

FIELD STRENGTH/SEQUENCE

3 T; spin-echo echo-planar imaging-diffusion-weighted imaging (DWI); T2-weighted, fluid-attenuated inversion recovery (FLAIR), T2*-weighted gradient-recalled echo and T1-weighted.

ASSESSMENT

The hematoma and PHE volumes at 24 hours and 5 days after symptom onset were measured in 121 patients with spontaneous ICH who had been administered standard medical treatment. Patients were grouped into two categories: those with sciSVC and those without. The imaging marker of sciSVC was defined as white matter hyperintensities (WMHs) Fazekas 2-3 combined cavitating lacunes.

STATISTICAL TESTS

Univariable analyses, χ² test, Mann-Whitney U test, and multiple linear regression.

RESULTS

The presence of sciSVC (multiple lacunes and confluent WMH) had a significant negative influence on PHE progress (Beta = -5.3 mL, 95% CI = -10.3 mL to -0.3 mL), and hematoma absorption (Beta = -3.2 mL, 95% CI = -5.9 mL to -0.4 mL) compared to that observed in the absence of sciSVC, as determined by multivariate linear regression analysis.

DATA CONCLUSIONS

The presence of sciSVC (multiple lacunes and confluent WMH) negatively influenced hematoma absorption and PHE progress in ICH patients.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 3.

Lipoprotein(a) and residual vascular risk in statin-treated patients with first acute ischemic stroke: A prospective cohort study

OBJECTIVES

Statins either barely affect or increase lipoprotein(a) [Lp(a)] levels. This study aimed to explore the factors correlated to the change of Lp(a) levels as well as the relationship between Lp(a) and the recurrent vascular events in statin-treated patients with first acute ischemic stroke (AIS).

METHODS

Patients who were admitted to the hospital with first AIS from October 2018 to September 2020 were eligible for inclusion. Correlation between the change of Lp(a) levels and potential influencing factors was assessed by linear regression analysis. Cox proportional regression models were used to estimate the association between Lp(a) and recurrent vascular events including AIS, transient ischemic attack, myocardial infarction and coronary revascularization.

RESULTS

In total, 303 patients, 69.6% males with mean age 64.26 ± 11.38 years, completed the follow-up. During the follow-up period, Lp(a) levels increased in 50.5% of statin-treated patients and the mean percent change of Lp(a) levels were 14.48% (95% CI 6.35-22.61%). Creatinine (β = 0.152, 95% CI 0.125-0.791, P = 0.007) and aspartate aminotransferase (AST) (β = 0.160, 95% CI 0.175-0.949, P = 0.005) were positively associated with the percent change of Lp(a) levels. During a median follow-up of 26 months, 66 (21.8%) patients had a recurrent vascular event. The median time period between AIS onset and vascular events recurrence was 9.5 months (IQR 2.0-16.3 months). The on-statin Lp(a) level ≥70 mg/dL (HR 2.539, 95% CI 1.076-5.990, P = 0.033) and the change of Lp(a) levels (HR 1.003, 95% CI 1.000-1.005, P = 0.033) were associated with the recurrent vascular events in statin-treated patients with first AIS. Furthermore, the on-statin Lp(a) levels ≥70 mg/dL (HR 3.612, 95% CI 1.018-12.815, P = 0.047) increased the risk of recurrent vascular events in patients with low-density lipoprotein cholesterol (LDL-C) levels < 1.8 mmol/L.

CONCLUSIONS

Lp(a) levels increased in half of statin-treated patients with first AIS. Creatinine and AST were positively associated with the percent change of Lp(a) levels. Lp(a) is a determinant of residual vascular risk and the change of Lp(a) is positively associated with the risk of recurrent vascular events in these patients.

Impact of Hemorrhagic Stroke on Molar Bite Force: A Prospective Study

Stroke is a neurological deficit of cerebrovascular origin that promotes physical impairments of adult individuals. The present study is aimed to demonstrate whether hemorrhagic stroke affects the maximum molar bite force. The prospective study carried in Centro Universitario Claretiano de Batatais, Brazil, determined the distribution of the sample into two groups: hemorrhagic stroke group (n=18, median age, 62.5 years) and disease-free group (n=18, median age, 62.0 years), with 10 men and 8 women in each group. Subjects were paired one-to-one (age and body mass index). The dynamometer was used to measure the maximum molar bite force (right and left). All analyses were performed with a significance level of 5% (Student's t-test). Differences were found on the right (p=0.048) and left (p=0.042) molar bite force, with lower bite force (both sides) in hemorrhagic stroke group. The study suggests that hemorrhagic stroke negatively affects the maximum molar bite force and necessitates changes in food intake to nutritious and softer consistency foods.

Neurovascular Coupling Is Impaired in Hypertensive and Diabetic Subjects Without Symptomatic Cerebrovascular Disease

The mechanistic link between hypertension, diabetes and cerebral small vessel disease (CSVD) is still poorly understood. We hypothesized that hypertension and diabetes could impair cerebrovascular regulation prior to irreversibly established cerebrovascular disease. In this study, 52 hypertensive patients [54% males; age 64 ± 11 years; 58% with comorbid diabetes mellitus (DM)] without symptomatic cerebrovascular disease underwent transcranial Doppler (TCD) monitoring in the middle (MCA) and posterior (PCA) cerebral arteries, to assess vasoreactivity to carbon dioxide (VRCO₂) and neurovascular coupling (NVC). 1.5T magnetic resonance imaging was also performed and white matter hyperintensity volume was automatically segmented from FLAIR sequences. TCD data from 17 healthy controls were obtained for comparison (47% males; age 60 ± 16 years). Hypertensive patients showed significant impairment of NVC in the PCA, with reduced increment in cerebral blood flow velocity during visual stimulation (22.4 ± 9.2 vs. 31.6 ± 5.7, p < 0.001), as well as disturbed NVC time-varying properties, with slower response (lower rate time: 0.00 ± 0.02 vs. 0.03 ± 6.81, p = 0.001), and reduced system oscillation (reduced natural frequency: 0.18 ± 0.08 vs. 0.22 ± 0.06, p < 0.001), when compared to controls. VRCO₂ remained relatively preserved in MCA and PCA. These results were worse in hypertensive diabetic patients, with lower natural frequency (p = 0.043) than non-diabetic patients. White matter disease burden did not predict worse NVC. These findings suggest that hypertensive diabetic patients may have a precocious impairment of NVC, already occurring without symptomatic CSVD. Future research is warranted to evaluate whether NVC assessment could be useful as an early, non-invasive, surrogate marker for CSVD.

Prediction of Cerebral Aneurysm Hemodynamics With Porous-Medium Models of Flow-Diverting Stents via Deep Learning

The interventional treatment of cerebral aneurysm requires hemodynamics to provide proper guidance. Computational fluid dynamics (CFD) is gradually used in calculating cerebral aneurysm hemodynamics before and after flow-diverting (FD) stent placement. However, the complex operation (such as the construction and placement simulation of fully resolved or porous-medium FD stent) and high computational cost of CFD hinder its application. To solve these problems, we applied aneurysm hemodynamics point cloud data sets and a deep learning network with double input and sampling channels. The flexible point cloud format can represent the geometry and flow distribution of different aneurysms before and after FD stent (represented by porous medium layer) placement with high resolution. The proposed network can directly analyze the relationship between aneurysm geometry and internal hemodynamics, to further realize the flow field prediction and avoid the complex operation of CFD. Statistical analysis shows that the prediction results of hemodynamics by our deep learning method are consistent with the CFD method (error function <13%), but the calculation time is significantly reduced 1,800 times. This study develops a novel deep learning method that can accurately predict the hemodynamics of different cerebral aneurysms before and after FD stent placement with low computational cost and simple operation processes.

Intraventricular Hemorrhage Growth: Definition, Prevalence and Association with Hematoma Expansion and Prognosis

BACKGROUND/OBJECTIVES

The objective of this study is to propose a definition of intraventricular hemorrhage (IVH) growth and to investigate whether IVH growth is associated with ICH expansion and functional outcome.

METHODS

We performed a prospective observational study of ICH patients between July 2011 and March 2017 in a tertiary hospital. Patients were included if they had a baseline CT scan within 6 h after onset of symptoms and a follow-up CT within 36 h. IVH growth was defined as either any newly occurring intraventricular bleeding on follow-up CT scan in patients without baseline IVH or an increase in IVH volume ≥ 1 mL on follow-up CT scan in patients with initial IVH. Poor outcome was defined as modified Rankin Scale score of 3-6 at 90 days. The association between IVH growth and functional outcome was assessed by using multivariable logistic regression analysis.

RESULTS

IVH growth was observed in 59 (19.5%) of 303 patients. Patients with IVH growth had larger baseline hematoma volume, higher NIHSS score and lower GCS score than those without. Of 44 patients who had concurrent IVH growth and hematoma growth, 41 (93.2%) had poor functional outcome at 3-month follow-up. IVH growth (adjusted OR 4.15, 95% CI 1.31-13.20; P = 0.016) was an independent predictor of poor functional outcome (mRS 3-6) at 3 months in multivariable analysis.

CONCLUSION

IVH growth is not uncommon and independently predicts poor outcome in ICH patients. It may serve as a promising therapeutic target for intervention.

Fibroblast growth factor 23 is associated with risk of intracerebral hemorrhage

BACKGROUND AND PURPOSE

Fibroblast growth factor 23 (FGF23) is an osteogenic hormone associated with chronic kidney disease and is an emerging risk factor for several cardiovascular diseases. The association of FGF23 with stroke is unclear. The aim of this study was to investigate the association of FGF23 with incident intracerebral hemorrhage (ICH).

METHODS

This was a nested case-control study of 220 ICH cases and 244 age- and sex-matched controls from the population-based Malmö Diet and Cancer Study (n = 28,449). Incident ICH cases were ascertained using national registers and classified by bleeding location. Logistic regression was used to study the association of plasma levels of FGF23 with incident ICH, adjusting for potential ICH risk factors. Subgroup analyses were performed for lobar and non-lobar ICH, fatal ICH, ICH with large volume and ICH with poor functional outcome, respectively.

RESULTS

Higher FGF23 levels at baseline were significantly associated with incident ICH. After multivariable adjustment, the odds ratio for the association with all ICH was 1.84 (95% confidence interval [CI] 1.25-2.71, p = 0.002) per doubling of FGF23 concentration. For lobar and non-lobar ICH, odds ratios were 1.73 (95% CI 1.04-2.87, p = 0.035) and 2.13 (95% CI 1.32-3.45, p = 0.002), respectively. FGF23 was also significantly associated with fatal ICH, ICH with large volume and ICH with poor functional outcome.

CONCLUSIONS

Higher FGF23 was associated with incident ICH in this nested case-control study. Further studies are required to explore whether the association is causal.

Antithrombotic Treatment for Peripheral Arterial Occlusive Disease

BACKGROUND

Patients with peripheral arterial occlusive disease (PAOD) are at elevated risk for cardiovascular events and vascular events affecting the limbs. The goals of antithrombotic treatment are to keep vessels open after revascularization, to prevent cardiovascular events, and to lessen the frequency of peripheral ischemia and of amputation.

METHODS

This review is based on pertinent publications retrieved by a selective literature search, with particular attention to meta-analyses, randomized controlled trials, and the German and European angiological guidelines.

RESULTS

Diabetes mellitus and nicotine abuse are the main risk factors for lower limb PAOD. The evidence for the efficacy and safety of antithrombotic treatment in patients with PAOD is limited, in particular, after surgical or endovascular revascularization. Intensifying antithrombotic treatment with stronger antiplatelet therapy (APT), dual antiplatelet therapy (DAPT), or antiplatelet therapy combined with anticoagulation lowers the rate of peripheral revascularization (relative risk [RR] 0.89; 95% confidence interval [0.83; 0.94]), amputation (RR 0.63; [0.46; 0.86]), and stroke (RR 0.82; [0.70; 0.97]) but raises the risk of bleeding (RR 1.23; [1.04; 1.44]). Predictors for peripheral vascular events include critical limb ischemia and having previously undergone a revascularization procedure or an amputation.

CONCLUSION

Antiplatelet therapy should only be intensified for a limited time, or if the risk of ischemia is high. Before and during intensified antiplatelet therapy, the risk of bleeding should be assessed and weighed against the risk of ischemia. No validated score is available to estimate the risk of hemorrhagic complications in patients with PAOD. New antithrombotic therapies should not be used indiscriminately, but should rather be reserved for selected groups of patients.

Arterial Spin Labeling Imaging Assessment of Cerebrovascular Reactivity in Hypertensive Small Vessel Disease

Objective: Cerebrovascular reactivity (CVR) represents the phenomenon where cerebral vessels dilate or constrict in response to vasoactive stimuli. CVR impairment may contribute to brain injury due to cerebral small vessel disease (SVD). We aimed to determine the CVR in hypertensive intracerebral hemorrhage (ICH) and to identify its vascular dysfunction.

Methods: A total of 21 patients with spontaneous hypertensive ICH (strictly deep or mixed deep and lobar hemorrhages, mean age 62.5 ± 11.3 years) and 10 control subjects (mean age 66.1 ± 6.0 years) were enrolled for CVR measurement at least 3 months after the symptomatic ICH event. Each participant underwent a brain MRI study, and CVR was calculated as the cerebral blood flow (CBF) reduction using arterial spin labeling (ASL) between baseline and 10 min after an intravenous dipyridamole injection (0.57 mg/kg). Traditional MRI markers for SVD were also evaluated, including cerebral microbleed, white matter hyperintensity, lacune, and MRI-visible enlarged perivascular space, which were used to determine the total small vessel disease score.

Results: Compared to control subjects, hypertensive ICH patients showed reduced CVR in the basal ganglia (CBF reduction 22.4 ± 22.7% vs. 41.7 ± 18.3, p = 0.026), the frontal lobe (15.1 ± 11.9 vs. 26.6 ± 9.9, p = 0.013), and the temporal lobe (14.7 ± 11.1 vs. 26.2 ± 10.0, p = 0.010). These differences remained significant in multivariable models after adjusting for age and sex. Within ICH groups, the CBF reduction in the basal ganglia was significantly correlated with the total small vessel disease score (R = 0.58, p = 0.006), but not with individual MRI markers.

Conclusion: Patients with advanced hypertensive SVD demonstrated impaired vasoconstriction after dipyridamole challenge in the basal ganglia and the frontal and temporal lobes. Our findings provide safe approaches for whole-brain CVR mapping in SVD and identify a potential physiological basis for vascular dysfunction in hypertensive SVD.

Effect of methylenetetrahydrofolate reductase gene polymorphisms and oxidative stress in silent brain infarction

Ischemic infarctions occur under the influence of genetic and environmental factors. In our study, the role of ischemia-modified albumin and thiol balance, which are new markers in determining oxidative damage together with MTHFR gene polymorphisms and homocysteine levels, in the development of SBI was investigated. White matter lesions in the magnetic resonance imaging (MRI) results of the patients were evaluated according to the Fazekas scale and divided into groups (Grade 0, 1, 2, and 3). Homocysteine, folate, B12, IMA, total thiol, and native thiol were measured by biochemical methods. The polymorphisms in MTHFR genes were investigated by the RT-PCR method. According to our results, a significant difference was found between the groups in age, homocysteine, folate, IMA, total thiol, and native thiol parameters (p < 0.05). When we compared the groups in terms of genotypes of the C677T gene, we found a significant difference in TT genotype between grades 0/3 and 1/3 (p < 0.05). We determined that homocysteine and IMA levels increased and folate levels decreased in CC/TT and CT/TT genotypes in the C677T gene (p < 0.05). Considering our results, the observation of homocysteine and IMA changes at the genotype level of the MTHFR C677T gene and between the groups, and the deterioration of thiol balance between the groups suggested that these markers can be used in the diagnosis of silent brain infarction.

Incidence of stroke and its association with glycemic control and lifestyle in Japanese patients with type 2 diabetes mellitus: The Fukuoka diabetes registry

AIMS

We prospectively investigated the incidence of stroke and its subtypes, risk factors and prognosis in Japanese patients with type 2 diabetes.

METHODS

A total of 4,875 participants with type 2 diabetes (mean age 65.4 years, male 57%, previous stroke 10%) were investigated for the development of stroke for 5 years. Risk factors were evaluated using multivariable adjusted Cox proportional models.

RESULTS

The incidence rates per 1,000 person-years were 6.7 for new-onset stroke (ischemic 5.5, hemorrhagic 1.2) and 22.7 for recurrent stroke (ischemic 18.8, hemorrhagic 3.8), respectively. Ischemic stroke was significantly associated with age, male, reduced regular physical activity, HbA_1c, diabetic kidney disease and previous stroke. Lacunar infarction was significantly associated with obesity, reduced regular physical activity, HbA_1c and diabetic kidney disease, whereas atherothrombotic stroke was significantly associated with age, reduced intake of dietary fiber, reduced regular physical activity, HbA_1c and previous stroke. Recurrent stroke was significantly associated with depressive symptom. Thirty-day and one-year survival was 76% and 64% for hemorrhagic stroke, and 96% and 91% for ischemic stroke, respectively.

CONCLUSIONS

The current study reemphasized the importance of glycemic control and lifestyle modification such as regular physical exercise for stroke prevention in patients with type 2 diabetes.

Long-Term Vascular Outcomes in Patients With Mixed Location Intracerebral Hemorrhage and Microbleeds

OBJECTIVE

To determine whether mixed location intracerebral hemorrhages/microbleeds (mixed ICH) is a risk factor for vascular unfavorable outcome compared to cerebral amyloid angiopathy-related ICH (CAA-ICH) or strictly deep hypertensive ICH/microbleeds (HTN-ICH).

METHODS

A total of 300 patients with spontaneous ICH were included. Clinical data, neuroimaging markers, and follow-up outcomes (recurrent ICH, ischemic stroke, and vascular death) were compared among mixed ICH (n = 148), CAA-ICH (n = 32), and HTN-ICH (n = 120). The association between follow-up events and neuroimaging markers was explored using multivariable Cox regression models.

RESULTS

Patients with mixed ICH were older (65.6 ± 12.1 years vs 58.1 ± 13.3 years, p < 0.001) than patients with HTN-ICH, but younger than patients with CAA-ICH (73.3 ± 13.8 years, p = 0.001). Compared to CAA-ICH, mixed ICH had similar incidence of vascular events (all p > 0.05). Compared to HTN-ICH, mixed ICH is associated with higher ICH recurrence (hazard ratio [HR] 3.0, 95% confidence interval [CI] 1.2-7.7), more ischemic stroke (HR 8.2, 95% CI 1.0-65.8), and vascular composite outcome (HR 3.5, 95% CI 1.5-8.2) after adjustment for age and sex. In patients with mixed ICH, the presence of cortical superficial siderosis (cSS) is associated the development of ICH recurrence (HR 4.8, 95% CI 1.0-23.2), ischemic stroke (HR 8.8, 95% CI 1.7-45.5), and vascular composite outcome (HR 6.2, 95% CI 1.9-20.2). The association between cSS and ischemic stroke (p = 0.01) or vascular composite outcome (p = 0.003) remained significant after further adjustment for other radiologic markers.

CONCLUSIONS

Mixed ICH harbors higher risk of unfavorable vascular outcome than HTN-ICH. Presence of cSS in mixed ICH independently predicts vascular event, suggesting the contribution of detrimental effect due to coexisting CAA.

Magnetic resonance imaging manifestations of cerebral small vessel disease: automated quantification and clinical application

The common cerebral small vessel disease (CSVD) neuroimaging features visible on conventional structural magnetic resonance imaging include recent small subcortical infarcts, lacunes, white matter hyperintensities, perivascular spaces, microbleeds, and brain atrophy. The CSVD neuroimaging features have shared and distinct clinical consequences, and the automatic quantification methods for these features are increasingly used in research and clinical settings. This review article explores the recent progress in CSVD neuroimaging feature quantification and provides an overview of the clinical consequences of these CSVD features as well as the possibilities of using these features as endpoints in clinical trials. The added value of CSVD neuroimaging quantification is also discussed for researches focused on the mechanism of CSVD and the prognosis in subjects with CSVD.

Asymptomatic Striatocapsular slit-like Hemorrhage as a Severity Marker in Patients with Hypertensive Angiopathy

BACKGROUND

Concomitant asymptomatic striatocapsular slit-like hemorrhage (SSH) is occasionally found in patients of spontaneous intracerebral hemorrhage (ICH), but was seldomly described in the literature. In this study, we described the clinico-radiological features of asymptomatic SSH in ICH patients with hypertensive microangiopathy.

METHODS AND RESULTS

246 patients with strictly deep or mixed deep and lobar ICH/microbleeds were included. SSH was defined as hypointense lesions involving the lateral aspect of lentiform nucleus or external capsule in slit shape (>1.5 cm) on susceptibility-weighted imaging without history of associated symptoms. Demographics and neuroimaging markers were compared between patients with SSH and those without. Patients with SSH (n=24, 10%) and without SSH had comparable age (62.0 ± 12.6 vs. 62.3 ± 13.5, p = 0.912) and vascular risk factor profiles including the diagnosis of chronic hypertension, diabetes, and dyslipidemia (all p>0.05). SSH was associated with more common lobar microbleeds (79.2% vs 48.2%, p = 0.005), lacunes (75% vs. 41.4%, p = 0.002) and higher white matter hyperintensity (WMH) volumes (24.1 [10.4-46.3] vs. 13.9 [7.0-24.8] mL, p = 0.012) on MRI, as well as more frequent left ventricular hypertrophy (LVH) (50.0% vs. 20.5%, p = 0.004) and albuminuria (41.7% vs. 19.4%, p = 0.018). In multivariable analyses, SSH remains independently associated with LVH (p = 0.017) and albuminuria (p = 0.032) after adjustment for age, sex, microbleed, lacune and WMH volume.

CONCLUSIONS

Asymptomatic SSH is associated with more severe cerebral small vessel disease-related change on brain MRI, and hypertensive cardiac and renal injury, suggesting a more advanced stage of chronic hypertension.

Modeling blood-brain barrier pathology in cerebrovascular disease in vitro: current and future paradigms

The complexity of the blood-brain barrier (BBB) and neurovascular unit (NVU) was and still is a challenge to bridge. A highly selective, restrictive and dynamic barrier, formed at the interface of blood and brain, the BBB is a "gatekeeper" and guardian of brain homeostasis and it also acts as a "sensor" of pathological events in blood and brain. The majority of brain and cerebrovascular pathologies are associated with BBB dysfunction, where changes at the BBB can lead to or support disease development. Thus, an ultimate goal of BBB research is to develop competent and highly translational models to understand mechanisms of BBB/NVU pathology and enable discovery and development of therapeutic strategies to improve vascular health and for the efficient delivery of drugs. This review article focuses on the progress being made to model BBB injury in cerebrovascular diseases in vitro.

Pharmacological management of modifiable cardiovascular risk factors (blood pressure and lipids) following diagnosis of myocardial infarction, stroke and diabetes: comparison between population-based studies in Russia and Norway

BACKGROUND

Cardiovascular disease (CVD) mortality is substantially higher in Russia than in neighbouring Norway. We aimed to compare blood pressure- and lipid-lowering medication use and proportion meeting treatment targets between general population samples in the two countries in those with CVD and diabetes.

METHODS

The study population was adults aged 40-69 years reporting a diagnosis of myocardial infarction (MI), stroke and/or diabetes participating in cross-sectional population-based studies in Russia (Know Your Heart (KYH) 2015-18 N = 626) and Norway (The Tromsø Study 2015-16 (Tromsø 7) N = 1353). Reported medications were coded according to the 2016 WHO Anatomical Therapeutic Chemical Classification system. Treatment targets were defined using the Joint European Societies guidelines for CVD prevention in clinical practice (2016).

RESULTS

Age- and sex-standardized prevalence of use of lipid-lowering medications was higher in Tromsø 7 for all three conditions with a disproportionately large difference in those reporting MI (+ 48% (95% CI 39, 57%)). Proportion meeting treatment targets for LDL cholesterol was poor in both studies (age- and sex-standardized prevalence of control KYH vs Tromsø 7: MI 5.1% vs 10.1%; stroke 11.6% vs 5.8%; diabetes 24.9% vs 23.3%). Use of antihypertensive medication was higher in KYH for stroke (+ 40% (95% CI 30, 50%)) and diabetes (+ 27% (95% CI 19, 34%)) groups but approximately equal for the MI group (- 1% (95% CI -1, 1%)). Proportion meeting blood pressure targets was lower in KYH vs Tromsø 7 (MI 51.8% vs 76.3%; stroke 49.5% vs 69.6%; diabetes 51.9% vs 63.9%).

CONCLUSIONS

We identified different patterns of medication use in people with CVD and diabetes. However despite higher use of lipid-lowering medication in the Norwegian study treatment to target for total cholesterol was poor in both Russian and Norwegian studies. In contrast we found higher levels of use of antihypertensive medications in the Russian study but also that less participants met treatment targets for blood pressure. Further work should investigate what factors are responsible for this seeming paradox and how management of modifiable risk factors for secondary prevention could be improved.

Hemispheric Asymmetry of White Matter Hyperintensity in Association With Lacunar Infarction

Background

White matter hyperintensities (WMHs) are commonly asymmetric between hemispheres but for unknown reasons. We investigated asymmetric WMHs associated with lacunar infarcts.

Methods and Results

A total of 267 consecutive patients with small first‐ever supratentorial infarcts (≤20 mm) were included. None had a relevant vascular stenosis. WMH asymmetry was measured based on the hemispheric difference of a modified Scheltens scale score (≥3 defined as asymmetric). We analyzed the association of the hemispheric WMH asymmetry with old silent lacunar infarcts or acute lacunar infarcts. We compared lesion frequency maps between groups and generated t‐statistics maps. The mean age of patients was 64 years, and 63% were men. Asymmetric WMH was more than 3‐fold as frequent (P<0.001) in the group with old silent lacunar infarcts (42%, 43/102) than in the group without old silent lacunar infarcts (15%, 24/165). In patients with left hemispheric dominance of WMHs, an acute lacunar infarct was more likely to be located in the left (versus right) hemisphere (74% versus 26%, P<0.001). In patients with right hemispheric dominance of WMHs, an acute lacunar infarct was more likely to be located on the right (versus left) hemisphere (81% versus 19%, P<0.001). Mapping studies showed that the side of hemispheric dominance of WMHs was associated with acute and silent lacunes on the same side.

Conclusions

These are the first data to show that asymmetric WMHs are associated with both old silent lacunar infarcts and acute lacunar infarcts ipsilateral to the greatest WMH burden. This suggests that the hemisphere with relatively large WMHs is more vulnerable to ischemia.

Anton's syndrome: a rare and unusual form of blindness

Anton syndrome is characterised by visual anosognosia. It results from damage to both occipital lobes, while the anterior visual pathways remain intact. We describe four cases of Anton's syndrome. First case is that of a 73-year-old woman, who presented with two separate events of intraparenchymal brain haemorrhage, 4 years apart. Her first stroke affected the left and second affected the right occipital lobe. Bilateral occipital lobe damage resulted in cortical blindness. Second case is an 88-year-old man, who suffered from two ischaemic strokes, 2 days apart. Each stroke involved one posterior cerebral artery. This resulted in bilateral occipital and temporal lobe infarcts. Third case is a 64-year-old woman with chronic renal failure, who suffered bilateral occipital lobe infarction after haemodialysis, due to posterior reversible encephalopathy syndrome. Last case is that of an 80-year-old woman who suffered a basilar artery stroke, resulting in bilateral thalamic, temporal and occipital lobe infarction.

Involvement of Epigenetic Mechanisms and Non-coding RNAs in Blood-Brain Barrier and Neurovascular Unit Injury and Recovery After Stroke

Cessation of blood flow leads to a complex cascade of pathophysiological events at the blood-vascular-parenchymal interface which evolves over time and space, and results in damage to neural cells and edema formation. Cerebral ischemic injury evokes a profound and deleterious upregulation in inflammation and triggers multiple cell death pathways, but it also induces a series of the events associated with regenerative responses, including vascular remodeling, angiogenesis, and neurogenesis. Emerging evidence suggests that epigenetic reprograming could play a pivotal role in ongoing post-stroke neurovascular unit (NVU) changes and recovery. This review summarizes current knowledge about post-stroke recovery processes at the NVU, as well as epigenetic mechanisms and modifiers (e.g., DNA methylation, histone modifying enzymes and microRNAs) associated with stroke injury, and NVU repair. It also discusses novel drug targets and therapeutic strategies for enhancing post-stroke recovery.

Cerebral small vessel disease: classification, clinical manifestations, diagnosis, and features of treatment

The paper considers the relevance of the problem of cerebral small vessel disease (CSVD) that is an important cause of ischemic and hemorrhagic stroke, associated with the development of cognitive impairment and complications of antithrombotic therapy. It presents briefly the current issues of etiology and pathogenesis of the disease. Sporadic non-amyloid microangiopathy, cerebral amyloid angiopathy, and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are discussed in detail from the point of view of their clinical presentation, neuroimaging, and features of therapeutic tactics. An algorithm for diagnosing CSVD in patients admitted to hospital for stroke and a differentiated approach to their treatment are proposed. Consideration of the neuroimaging manifestations of CSVD is noted to be necessary for the safe and more effective treatment of patients with cerebrovascular diseases.

Pretreatment Blood Pressure is a Simple Predictor of Hemorrhagic Infarction after Intravenous Recombinant Tissue Plasminogen Activator (rt-PA) Therapy

BACKGROUND

Hemorrhagic infarction (HI) is among the most severe complications that can occur following the administration of intravenous recombinant tissue plasminogen activator (rt-PA). In the present study, we aimed to determine the optimal cut-off points of blood pressure (BP) for HI after rt-PA treatment, and to compare our findings with those for other prediction models.

METHODS

We analyzed data from 109 consecutive patients with stroke treated at our hospital between 2009 and 2016. HI was confirmed via computed tomography or magnetic resonance imaging. Patients were classified into a symptomatic HI group, an asymptomatic HI group, and a non-HI group. BP was measured on admission and before rt-PA treatment. Glucose Race Age Sex Pressure Stroke Severity (GRASPS) and Totaled Health Risks in Vascular Events (THRIVE) scores were also calculated. Receiver operating characteristic (ROC) analysis was used to determine factors associated with symptomatic and asymptomatic HI.

RESULTS

Among the 109 total patients, 25 patients developed symptomatic HI, while 22 patients developed asymptomatic HI. ROC analysis for predicting symptomatic and asymptomatic HI revealed that the area under the curve for pretreatment systolic BP (SBP) was .88 (95% confidence interval[CI]: .83-.94), while those for GRASPS and THRIVE scores were .75 (95% CI: .66-.85) and .69 (95% CI: .59-.79), respectively. We identified an optimal cut-off point of 160 mm Hg (sensitivity: 82.3%; specificity: 76.6%; diagnostic accuracy: 80.0%; positive predictive value: 76.6%; negative predictive value: 82.5%).

CONCLUSIONS

Pre-treatment SBP may be a simple predictor of symptomatic and asymptomatic HI in patients with stroke undergoing rt-PA treatment.

Interarm Blood Pressure Difference has Various Associations with the Presence and Burden of Cerebral Small-Vessel Diseases in Noncardioembolic Stroke Patients

Background and Purpose

An interarm blood pressure difference (IABD) is independently related to the occurrence of cardiovascular disease and mortality. Cerebral small-vessel diseases (SVDs) are important risk factors for stroke, cognitive dysfunction, and mortality. We aimed to determine whether IABD is related to cerebral SVDs.

Methods

This study included 1,205 consecutive noncardioembolic ischemic stroke patients as confirmed by brain MRI and simultaneously measured the bilateral brachial blood pressures. We investigated cerebral SVDs based on high-grade white-matter hyperintensities (HWHs), presence of cerebral microbleeds (CMBs), high-grade perivascular spaces (HPVSs), and asymptomatic lacunar infarctions (ALIs) on brain MRI.

Results

In multivariate logistic regression, an interarm systolic blood pressure difference (IASBD) ≥10 mm Hg was independently related to the existence of HWHs [odds ratio (OR)=1.94, 95% CI=1.32–2.84, p=0.011] and had a tendency to be associated with the presence of HPVSs (OR=1.45, 95% CI=0.49–2.23, p=0.089) and ALIs (OR=1.42, 95% CI=0.96–2.11, p=0.052), but not with the presence of CMBs (OR=1.09, 95% CI=0.73–1.61, p=0.634). In multivariate linear regression adjusted for age, sex, and variables with p<0.1 in the univariate analysis, IASBD ≥10 mm Hg and interarm diastolic blood pressure difference ≥10 mm Hg were significantly correlated with an increased total burden of SVDs (β=0.080 and p=0.006, and β=0.065 and p=0.023, respectively).

Conclusions

This study found that IABD ≥10 mm Hg was associated with the presence and increased burden of cerebral SVDs in noncardioembolic stroke patients. This suggests that IABD ≥10 mm Hg could be a useful indicator of the presence and burden of cerebral SVDs in stroke patients.

Updates on Prevention of Cardioembolic Strokes

Cardiac embolism continues to be a leading etiology of ischemic strokes worldwide. Although pathologies that result in cardioembolism have not changed over the past decade, there have been significant advances in the treatment and stroke prevention methods for these conditions. Atrial fibrillation remains the prototypical cause of cardioembolic strokes. The availability of new long-term monitoring devices for atrial fibrillation detection such as insertable cardiac monitors has allowed accurate detection of this leading cause of cardioembolism. The non-vitamin K antagonist oral anticoagulants have improved our ability to prevent strokes for many patients with non-valvular atrial fibrillation (NVAF). Advances in left atrial appendage closure and the U.S. Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device for stroke prevention in NVAF patients who have an appropriate rationale for a nonpharmacological alternative, have revolutionized the field and provided a viable option for patients at higher hemorrhagic risk. The role of patent foramen ovale closure for secondary prevention in selected patients experiencing cryptogenic ischemic strokes at a relatively young age has become clearer thanks to the very recent publication of long-term outcomes from three major studies. Advances in the management of infective endocarditis, heart failure, valvular diseases, and coronary artery disease have significantly changed the management of such patients, but have also revealed new concerns related to assessment of ischemic versus hemorrhagic risk in the setting of antithrombotic use. The current review article aims to discuss these advances especially as they pertain to the stroke neurology practice.