Two types of lacunar infarcts: further arguments from a study on prognosis

A severity comparison of leukoaraiosis in ischemic and hemorrhagic stroke: a retrospective study

Introduction

Leukoaraiosis (LA) is a common neuroradiological finding in patients suffering from stroke. Cerebral small-vessel disease (SVD) is one of the primary causes of both ischemic stroke and hemorrhagic stroke (intracerebral hemorrhage, ICH) and the development of LA. Significant evidence that LA predicts the risk of functional dependency and mortality exists. However, studies examining the difference in LA severity between ischemic stroke and hemorrhagic stroke are lacking. We therefore aimed to compare the severity and abundance of LA in the two stroke subgroups.

Methods

All patients admitted to the Department of Neurology, Haukeland University Hospital, with an ischemic stroke and intracerebral hemorrhagic (ICH) stroke diagnosed between 2006 and 2020 were included in the study. We collected patient data on risk factors and clinical and radiological findings and outcomes from our local stroke registry. The presence and severity of LA were assessed using the Fazekas score based on CT imaging. We evaluated the outcome using the modified Rankin Score (mRS) 7 days post-stroke.

Results

A total of 5,084 patients were included in our analyses: 4437 (87%) with ischemic stroke and 647 (13%) with ICH. LA was present in 2476 (45%) patients. In our ordinal logistic regression model, adjusting for age, sex, known hypertension, known diabetes mellitus, and smoking, LA was more severe and more abundant in ICH patients compared to ischemic stroke patients (Fazekas score: 1, OR: 1.54; Fazekas score: 2, OR: 1.88; and Fazekas score: 3, OR 2.13; p < 0.001). Increasing severity of LA was associated with worse functional outcomes in both groups (ischemic stroke, OR: 1.49; p < 0.001 and ICH, OR: 1.36; p < 0.025).

Conclusion

In this study, LA was more severe and abundant in patients with ICH.

Small vessel disease is associated with later onset of major adverse cardiovascular events after acute cervicocerebral artery dissection

BACKGROUND

Cerebral small vessel disease (CSVD) is common among the elderly and has been associated with an increased risk of major adverse cardiac events (MACE) and increased risk of long-term disability. Little is known whether CSVD affects outcomes after cervicocerebral artery dissection (CAD), which predominantly affects younger patients. Specifically, there is a paucity as to whether CSVD increases the risk of MACE after CAD and whether this risk is different for early versus late events.

METHODS

We retrospectively analyzed 140 consecutive patients with acute CAD. We determined CSVD on MRI using the STRIVE criteria and calculated the CSVD sum score based on the individual CSVD components. For statistical analysis the CSVD burden was dichotomized to mild (score 0-1) versus severe (score 2-4). The primary outcome of interest was the 6-month MACE risk. Secondary outcomes of interest were early versus late MACE, stroke at presentation, and good 90-day outcome (modified Rankin Scale score 0-2).

RESULTS

There was no difference in overall MACE between subjects when stratified by CSVD burden (10.1% versus 9.8%, Log-rank P = 0.953). We found that patients with severe CSVD had significantly more late MACE as compared to mild CSVD (9.8% versus 1.1%, P = 0.024). There was no significant difference in the prevalence of stroke at the time of CAD diagnosis (50.6% versus 47.1%, P = 0.690) and the 90-day disability-free survival in subjects with mild versus severe CSVD (93.7% versus 91.7%, P = 0.729).

CONCLUSION

Severe CSVD burden was associated with a significantly greater risk of late MACE. CSVD assessment in CAD patients may aid risk stratification and treatment optimization.

A typology of cerebral small vessel disease based on imaging markers

BACKGROUND

Lacunes, microbleeds, enlarged perivascular spaces (EPVS), and white matter hyperintensities (WMH) are brain imaging features of cerebral small vessel disease (SVD). Based on these imaging markers, we aimed to identify subtypes of SVD and to evaluate the validity of these markers as part of clinical ratings and as biomarkers for stroke outcome.

METHODS

In a cross-sectional study, we examined 1207 first-ever anterior circulation ischemic stroke patients (mean age 69.1 ± 15.4 years; mean NIHSS 5.3 ± 6.8). On acute stroke MRI, we assessed the numbers of lacunes and microbleeds and rated EPVS and deep and periventricular WMH. We used unsupervised learning to cluster patients based on these variables.

RESULTS

We identified five clusters, of which the last three appeared to represent distinct late stages of SVD. The two largest clusters had no to only mild or moderate WMH and EPVS, respectively, and favorable stroke outcome. The third cluster was characterized by the largest number of lacunes and a likewise favorable outcome. The fourth cluster had the highest age, most pronounced WMH, and poor outcome. Showing the worst outcome, the fifth cluster presented pronounced microbleeds and the most severe SVD burden.

CONCLUSION

The study confirmed the existence of different SVD types with different relationships to stroke outcome. EPVS and WMH were identified as imaging features of presumably early progression. The number of microbleeds and WMH severity appear to be promising biomarkers for distinguishing clinical subgroups. Further understanding of SVD progression might require consideration of refined SVD features, e.g., for EPVS and type of lacunes.

Higher-resolution quantification of white matter hypointensities by large-scale transfer learning from 2D images on the JPSC-AD cohort

White matter lesions (WML) commonly occur in older brains and are quantifiable on MRI, often used as a biomarker in Aging research. Although algorithms are regularly proposed that identify these lesions from T2‐fluid‐attenuated inversion recovery (FLAIR) sequences, none so far can estimate lesions directly from T1‐weighted images with acceptable accuracy. Since 3D T1 is a polyvalent and higher‐resolution sequence, it could be beneficial to obtain the distribution of WML directly from it. However a serious difficulty, both for algorithms and human, can be found in the ambiguities of brain signal intensity in T1 images. This manuscript shows that a cross‐domain ConvNet (Convolutional Neural Network) approach can help solve this problem. Still, this is non‐trivial, as it would appear to require a large and varied dataset (for robustness) labelled at the same high resolution (for spatial accuracy). Instead, our model was taught from two‐dimensional FLAIR images with a loss function designed to handle the super‐resolution need. And crucially, we leveraged a very large training set for this task, the recently assembled, multi‐sites Japan Prospective Studies Collaboration for Aging and Dementia (JPSC‐AD) cohort. We describe the two‐step procedure that we followed to handle such a large number of imperfectly labeled samples. A large‐scale accuracy evaluation conducted against FreeSurfer 7, and a further visual expert rating revealed that WML segmentation from our ConvNet was consistently better. Finally, we made a directly usable software program based on that trained ConvNet model, available at https://github.com/bthyreau/deep-T1-WMH.

The Heart Brain Team and Patient-Centered Management of Ischemic Stroke

The multifaceted connections between the heart and the brain have been extensively studied at the anatomy, pathophysiology, and clinical levels. Studies have suggested a vital role for both cardiologists and neurologists in the management of various cardiovascular and neurological disorders. However, a true heart-brain team-based approach remained confined to large, specialized centers. In this paper, we review the various intersection areas of cardiology and neurology with regard to ischemic stroke. We focus our discussion on the challenges and opportunity for a heart-team approach to stroke in the context of atrial fibrillation, carotid disease, and patent foramen ovale, and in the setting of strokes complicating transcatheter endovascular interventions.

Total magnetic resonance imaging of cerebral small vessel disease burden predicts dysphagia in patients with a single recent small subcortical infarct

Background

This study was performed to identify the association between the total magnetic resonance imaging burden of small vessel disease and the occurrence of post-stroke dysphagia in patients with a single recent small subcortical infarct (RSSI).

Methods

We retrospectively identified all patients with a magnetic resonance imaging-confirmed single RSSI. The water-swallowing test and volume-viscosity swallow test were performed within the first 24 h following admission to assess swallowing. Demographic and clinical data were extracted from our stroke database. Based on brain magnetic resonance imaging, we independently rated the presence of cerebral microbleeds, lacunes, white matter hyperintensities and enlarged perivascular spaces. The presence of each small vessel disease feature was summed to determine the total small vessel disease burden, ranging from 0 to 4.

Results

In total, 308 patients with a single RSSI were enrolled. Overall, 54 (17.5%) were diagnosed with post-stroke dysphagia. The risk factors related to post-stroke dysphagia included the following: older age, higher National Institute of Health Stroke Scale scores, higher C-reactive protein level and higher fibrinogen level. Based on multiple logistic regression, National Institute of Health Stroke Scale scores and total small vessel disease burden were independent risk factors of post-stroke dysphagia in patients with a single RSSI, after adjusting for age, gender, history of hypertension, C-reactive protein level and fibrinogen level.

Conclusions

Dysphagia in patients with a single RSSI was associated with a more severe total small vessel disease burden as reflected by MRI. Total MRI of cerebral small vessel disease burden may predict dysphagia in these patients. Furthermore, more severe total small vessel disease burden was associated with systemic inflammation.

The etiology, manifestations, and therapy of chronic cerebrovascular diseases

The paper presents the current etiopathogenetic classification of chronic cerebrovascular diseases (CVD) and discusses the role of hypertension, cerebral amyloid angiopathy, and genetically determined syndromes in the development of this pathological condition. It gives recommendations for the neuroradiological diagnosis of chronic CVD in accordance with the international standards. The paper discusses the clinical manifestations of chronic CVD, primarily vascular cognitive impairment. It discusses international guidelines for the examination and treatment of patients with chronic CVD, as well as the rules for stroke prevention in this patient cohort. The possibilities of pathogenetically based therapy in decreasing the severity of vascular cognitive impairment in the presence of chronic CVD are also highlighted.

Quantifying the Impact of Chronic Ischemic Injury on Clinical Outcomes in Acute Stroke With Machine Learning

Acute stroke is often superimposed on chronic damage from previous cerebrovascular events. This background will inevitably modulate the impact of acute injury on clinical outcomes to an extent that will depend on the precise anatomical pattern of damage. Previous attempts to quantify such modulation have employed only reductive models that ignore anatomical detail. The combination of automated image processing, large-scale data, and machine learning now enables us to quantify the impact of this with high-dimensional multivariate models sensitive to individual variations in the detailed anatomical pattern. We introduce and validate a new automated chronic lesion segmentation routine for use with non-contrast CT brain scans, combining non-parametric outlier-detection score, Zeta, with an unsupervised 3-dimensional maximum-flow, minimum-cut algorithm. The routine was then applied to a dataset of 1,704 stroke patient scans, obtained at their presentation to a hyper-acute stroke unit (St George's Hospital, London, UK), and used to train a support vector machine (SVM) model to predict between low (0-2) and high (3-6) pre-admission and discharge modified Rankin Scale (mRS) scores, quantifying performance by the area under the receiver operating curve (AUROC). In this single center retrospective observational study, our SVM models were able to differentiate between low (0-2) and high (3-6) pre-admission and discharge mRS scores with an AUROC of 0.77 (95% confidence interval of 0.74-0.79), and 0.76 (0.74-0.78), respectively. The chronic lesion segmentation routine achieved a mean (standard deviation) sensitivity, specificity and Dice similarity coefficient of 0.746 (0.069), 0.999 (0.001), and 0.717 (0.091), respectively. We have demonstrated that machine learning models capable of capturing the high-dimensional features of chronic injuries are able to stratify patients-at the time of presentation-by pre-admission and discharge mRS scores. Our fully automated chronic stroke lesion segmentation routine simplifies this process, and utilizes routinely collected CT head scans, thereby facilitating future large-scale studies to develop supportive clinical decision tools.

Subclinical Cerebrovascular Disease: Epidemiology and Treatment

PURPOSE OF REVIEW

Subclinical cerebrovascular disease (sCVD) is highly prevalent in older adults. The main neuroimaging findings of sCVD include white matter hyperintensities and silent brain infarcts on T2-weighted MRI and cerebral microbleeds on gradient echo or susceptibility-weighted MRI. In this paper, we will review the epidemiology of sCVD, the current evidence for best medical management, and future directions for sCVD research.

RECENT FINDINGS

Numerous epidemiologic studies show that sCVD, in particular WMH, is an important risk factor for the development of dementia, stroke, worse outcomes after stroke, gait instability, late-life depression, and death. Effective treatment of sCVD could have major consequences for the brain health of a substantial portion of older Americans. Despite the link between sCVD and many vascular risk factors, such as hypertension or hyperlipidemia, the optimal medical treatment of sCVD remains uncertain. Given the clinical equipoise about the risk versus benefit of aggressive medical management for sCVD, clinical trials to examine pragmatic, evidence-based approaches to management of sCVD are needed. Such a trial could provide much needed guidance on how to manage a common clinical scenario facing internists and neurologists in practice.

Association between excessive supraventricular ectopy and subclinical cerebrovascular disease: a population-based study

BACKGROUND AND PURPOSE

The association between an increased supraventricular ectopic beat (SVEB) and subclinical cerebrovascular disease remains unclear. Given the emerging concept that an increased SVEB is a marker of atrial cardiomyopathy or atherosclerosis burden, we sought to determine whether excessive supraventricular ectopic activity (ESVEA) is associated with a higher burden of subclinical cerebrovascular disease in the middle-aged to older cohort with neither apparent stroke nor atrial fibrillation.

METHODS

We conducted a cross-sectional population-based study of 462 men (mean age, 68.1 years) who underwent 24-h Holter electrocardiography and brain magnetic resonance imaging. ESVEA was defined as the presence of >10 SVEBs/h. Subclinical cerebrovascular diseases were defined as silent brain infarct (SBI), white matter hyperintensity (WMH) and intracranial atherosclerotic stenosis (ICAS). The association of ESVEA with the presence of subclinical cerebrovascular diseases was adjusted for potential confounding covariates.

RESULTS

A total of 88 (19.0%) participants had ESVEA and 81 (17.5%), 91 (19.7%) and 109 (23.6%) had SBI, WMH and ICAS, respectively. In multivariable-adjusted Poisson regression with robust error variance, ESVEA was associated with the presence of WMH (relative risk, 1.58; 95% confidence interval, 1.06-2.36) and ICAS (relative risk, 1.49; 95% confidence interval, 1.02-2.18), but not with that of SBI (relative risk, 1.32; 95% confidence interval, 0.86-2.01). These associations were consistent when the graded distributions of subclinical cerebrovascular diseases were applied as outcomes in ordinal logistic regression.

CONCLUSIONS

The ESVEA was independently associated with higher burdens of WMH and ICAS. This suggests that increased SVEBs might improve risk stratification of individuals at high risk of subclinical cerebrovascular disease and consequently apparent ischaemic stroke.

Are morphologic features of recent small subcortical infarcts related to specific etiologic aspects?

Background:

Recent small subcortical infarcts (RSSIs) mostly result from the occlusion of a single, small, brain artery due to intrinsic cerebral small-vessel disease (CSVD). Some RSSIs may be attributable to other causes such as cardiac embolism or large-artery disease, and their association with coexisting CSVD and vascular risk factors may vary with morphological magnetic resonance imaging (MRI) features.

Methods:

We retrospectively identified all inpatients with a single symptomatic MRI-confirmed RSSI between 2008 and 2013. RSSIs were rated for size, shape, location (i.e. anterior: basal ganglia and centrum semiovale posterior cerebral circulation: thalamus and pons) and MRI signs of concomitant CSVD. In a further step, clinical data, including detailed diagnostic workup and vascular risk factors, were analyzed with regard to RSSI features.

Results:

Among 335 RSSI patients (mean age 71.1 ± 12.1 years), 131 (39%) RSSIs were >15 mm in axial diameter and 66 (20%) were tubular shaped. Atrial fibrillation (AF) was present in 44 (13.1%) and an ipsilateral vessel stenosis > 50% in 30 (9%) patients. Arterial hypertension and CSVD MRI markers were more frequent in patients with anterior-circulation RSSIs, whereas diabetes was more prevalent in posterior-circulation RSSIs. Larger RSSIs occurred more frequently in the basal ganglia and pons, and the latter were associated with signs of large-artery atherosclerosis. Patients with concomitant AF had no specific MRI profile.

Conclusion:

Our findings suggest the contribution of different pathophysiological mechanisms to the occurrence of RSSIs in the anterior and posterior cerebral circulation. While there appears to be some general association of larger infarcts in the pons with large-artery disease, we found no pattern suggestive of AF in RSSIs.

Periodontitis as a risk indicator and predictor of poor outcome for lacunar infarct

AIM

To investigate the association between periodontitis (PD) and lacunar infarct (LI) as well as to analyse whether PD could be a predictor of poor functional prognosis in patients with LI.

MATERIAL AND METHODS

Full-mouth periodontal examination was done in 120 cases (patients with LI) and 157 healthy controls. Demographic, clinical, medical and neurological information were collected from all of them. In addition, a measure of periodontal inflammation and disease activity, namely the periodontal inflamed surface area (PISA), was also calculated for each patient. Poor functional outcome was considered as a modified Rankin Scale >2 at 3 months.

RESULTS

PD was independently associated with the presence of LI (OR = 3.3, p < 0.001). Poor outcome was observed in 31 patients with LI (25.8%), of which 90.3% had PD. A PISA value ≥727 mm² was an independent predictor of poor prognosis, after adjusting for clinical confounders (OR = 6.5, p = 0.001).

CONCLUSIONS

PD and LI were associated. Active moderate to severe PD predicted poor prognosis in patients with LI. Further evidence is warranted to confirm our results and investigate potential mechanisms behind this association.

MRI progression of cerebral small vessel disease and cognitive decline in patients with hypertension

OBJECTIVE

Hypertension is associated with cognitive deficits, probably because it is a major risk factor for the development of white matter hyperintensities (WMH), lacunes, and cerebral microbleeds, which are MRI markers of cerebral small vessel disease. Studies into associations between presence or progression of these MRI markers and cognitive decline in hypertensive patients are rare. We investigated the association of baseline presence and progression of MRI markers of cerebral small vessel disease with cognitive decline over 4 years in patients with hypertension.

METHODS

In this longitudinal study, hypertensive patients underwent neuropsychological assessments and brain MRI at baseline and after 4 years. Presence and progression of periventricular and subcortical WMH, lacunes, and cerebral microbleeds were visually rated.

RESULTS

In total, 128 hypertensive patients (90 patients with essential hypertension and 38 hypertensive lacunar stroke patients), mean age: 58.6 ± 12.2 years, were included. Progression of periventricular WMH was associated with cognitive decline in simple regression analysis (P = 0.001) and in multivariable analysis with correction for baseline WMH presence and potential confounders (P = 0.004). In this multivariable analysis, R of progression of periventricular WMH was 5.6%, whereas R of baseline presence of periventricular WMH was 0.6%. We did not find significant associations between baseline presence or progression of the other MRI markers and cognitive decline.

CONCLUSION

In patients with hypertension, progression of periventricular WMH over 4 years is associated with cognitive decline, whereas we could not show an association between baseline periventricular WMH and cognitive decline. These results emphasize the importance of preventing progression of WMH in hypertensive patients.

Pulmonary Arteriovenous Malformations Are Associated with Silent Brain Infarcts in Hereditary Hemorrhagic Telangiectasia Patients

BACKGROUND AND PURPOSE

There is a high prevalence of right-to-left shunting pulmonary arteriovenous malformations (PAVMs), which are stroke risk factors, in hereditary hemorrhagic telangiectasia (HHT) patients. While the prevalence of ischemic complications in HHT patients is known, the prevalence of silent brain infarcts (SBI) remains unknown. The purpose of this study was to determine the prevalence and risk factors for SBI in HHT patients.

MATERIALS AND METHODS

Our institutional HHT database was queried to identify HHT patients who received a baseline screening brain MRI from January 2000 to February 2017. This study group was further refined by excluding patients who had a history of clinical ischemic disease as defined by having a stroke or transient ischemic attack (TIA). Brain MRIs were reviewed for SBI. Baseline data on demographics, Curacao criteria, presence of PAVMs, and cardiovascular risk factors were collected. The primary outcome was SBI prevalence. We also examined which baseline patient characteristics were associated with SBI through univariate chi-square and Student t tests and multivariate logistic regression analyses.

RESULTS

Three hundred fifty three consecutive HHT patients from January 2000 to February 2017 with a screening brain MRI and no prior history of stroke/TIA were included. SBI prevalence was 9.9% (35/353). SBI patients were more likely to have PAVMs than non-SBI patients (80.6 vs. 53.1%, p = 0.005). The median age was 66 in the SBI group and 52 in the non-SBI group (p = 0.006). SBI patients had higher prevalence of hyperlipidemia (34.3 vs. 9.8%, p < 0.0001), hypertension (48.6 vs. 22.0%, p = 0.005), and tobacco use (25.7 vs. 9.8%, p = 0.005). No patients under 30 had SBI. In the 60-69 age group, the prevalence of SBI was 18.8% with rates of 28.6% in the PAVM group and 10.5% in the non-PAVM group. For patients ≥70 years old, the prevalence of SBI was 21.4% overall and 27.6% in the PAVM group and 10.5% in the non-PAVM group. On multivariate analysis, PAVMs (OR 3.62, 95% CI 1.46-10.40) and increasing age (OR 1.04, 95% CI 1.01-1.07) were independently associated with SBI.

CONCLUSIONS

Overall, a similar 10% SBI prevalence in the HHT cohort was noted as compared to the general population. However, the prevalence of SBI was higher in HHT patients with PAVMs when compared to that of the general population, particularly among patients than 60 years old. These findings highlight the need to accurately identify, and when appropriate, treat PAVMs in the HHT population especially given the multiple significant, clinical consequences of SBI.

Neutrophil Infiltration and Matrix Metalloproteinase-9 in Lacunar Infarction

We use the modified pial vessel disruption rat model to elucidate the cellular and molecular mechanisms of cavitation as it plays a role in lacunar infarction. Here we discuss the similarities between the genesis of pulmonary cavitation in various animal models and lacunar infarction in the cerebral cortex of rats. Both pathological processes involve the creation of a cavity surrounded by fibroblasts or reactive astrocytes. A crucial step in both, the lung and the cerebral cortex, appears to be the migration of neutrophils across the endothelial barrier into the parenchyma. In the lung and cerebral cortex this involves release of matrix metalloproteinase-9 (MMP-9). Inside the parenchyma neutrophils continue to release MMP-9. In both situations batimastat (BB-94) and minocycline reduce release of MMP-9 and prevent cavitation. In the cerebral cortex MMP-9 release by resident microglia plays an additional role. We therefore advance the hypothesis that cavitation in both tissues is driven by MMP-9 originating from invading neutrophils. Therapeutic intervention has to focus on these blood-borne intruder cells and specific MMP actions. Batimastat and its derivatives (marimastat, BB-1101, mCGS-27023-A, ilomastat, GM6001, CTK8G1150) are already in clinical or experimental use in humans for anti-cancer treatment, and these clinically relevant drugs could be repurposed to act as anti-inflammatory to counter neutrophil contribution to lung or cerebral cortex cavitation.

The cerebral circulation and cerebrovascular disease II: Pathogenesis of cerebrovascular disease

In this paper, we review the cerebral circulation and cerebrovascular disease (CVD) with an overview of the major types of CVD pathogenesis. These, as categorized here, are as follows: occlusive injury intrinsic to blood vessels, occlusive injury extrinsic to blood vessels, cerebral hypoperfusion, and cerebral hemorrhage. Following an overview of each of these categories, we conclude with a discussion of cerebral edema to illustrate how the pathological origins we covered can progress clinically. The content of this paper sets the stage for the detailed, clinically oriented discussion of stroke with which our series culminates in its subsequent Part III.

Do Lacunar Infarcts Have Different Aetiologies? Risk Factor Profiles of Lacunar Infarcts in Deep White Matter and Basal Ganglia: The Second Manifestations of ARTerial Disease-Magnetic Resonance Study

BACKGROUND

Evidence suggests that lacunar infarcts have different etiologies, possibly related to their anatomical location and vascular territory. We investigated the risk factor profiles of patients with new lacunar infarcts in the basal ganglia and deep white matter.

METHODS

Within the Second Manifestations of ARTerial disease-Magnetic Resonance study, a prospective cohort on brain changes on MRI in patients with symptomatic atherosclerotic disease, 679 patients (57 ± 9 years) had vascular screening and MRI at baseline and after a mean follow-up of 3.9 years. We investigated the association between vascular risk factors at baseline and appearance of new lacunar infarcts in the basal ganglia and deep white matter at follow-up.

RESULTS

New lacunar infarcts appeared in 44 patients in the basal ganglia and in 37 patients in the deep white matter. In multivariable analysis, older age, history of cerebrovascular disease, and baseline white matter hyperintensity (WMH) volume were associated with increased risk of new lacunar infarcts in both locations. Hyperhomocysteinemia was associated with increased risk of lacunar infarcts in the basal ganglia (relative risk [RR] 2.0; 95% CI 1.0-4.2), whereas carotid stenosis >70% (RR 2.5; 95% CI 1.2-5.0), smoking (per 10 pack-year: RR 1.1; 95% CI 1.0-1.3), hypertension (RR 3.4; 95% CI 1.2-9.7), and progression of WMH volume (RR 2.4; 95% CI 1.1-5.2) were associated with increased risk of lacunar infarcts in the deep white matter.

CONCLUSIONS

The different risk factor profiles for new lacunar infarcts in basal ganglia and deep white matter indicate different etiologies. The independent association between progression of WMH and new deep white matter lacunar infarcts suggest a common etiology for these radiological abnormalities.

Total Cerebral Small Vessel Disease MRI Score Is Associated with Cognitive Decline in Executive Function in Patients with Hypertension

Objectives: Hypertension is a major risk factor for white matter hyperintensities (WMH), lacunes, cerebral microbleeds, and perivascular spaces, which are MRI markers of cerebral small vessel disease (SVD). Studies have shown associations between these individual MRI markers and cognitive functioning and decline. Recently, a “total SVD score” was proposed in which the different MRI markers were combined into one measure of SVD, to capture total SVD-related brain damage. We investigated if this SVD score was associated with cognitive decline over 4 years in patients with hypertension.

Methods: In this longitudinal cohort study, 130 hypertensive patients (91 patients with uncomplicated hypertension and 39 hypertensive patients with a lacunar stroke) were included. They underwent a neuropsychological assessment at baseline and after 4 years. The presence of WMH, lacunes, cerebral microbleeds, and perivascular spaces were rated on baseline MRI. Presence of each individual marker was added to calculate the total SVD score (range 0–4) in each patient.

Results: Uncorrected linear regression analyses showed associations between SVD score and decline in overall cognition (p = 0.017), executive functioning (p < 0.001) and information processing speed (p = 0.037), but not with memory (p = 0.911). The association between SVD score and decline in overall cognition and executive function remained significant after adjustment for age, sex, education, anxiety and depression score, potential vascular risk factors, patient group, and baseline cognitive performance.

Conclusion: Our study shows that a total SVD score can predict cognitive decline, specifically in executive function, over 4 years in hypertensive patients. This emphasizes the importance of considering total brain damage due to SVD.

Update on cerebral small vessel disease: a dynamic whole-brain disease

Cerebral small vessel disease (CSVD) is a very common neurological disease in older people. It causes stroke and dementia, mood disturbance and gait problems. Since it is difficult to visualise CSVD pathologies in vivo, the diagnosis of CSVD has relied on imaging findings including white matter hyperintensities, lacunar ischaemic stroke, lacunes, microbleeds, visible perivascular spaces and many haemorrhagic strokes. However, variations in the use of definition and terms of these features have probably caused confusion and difficulties in interpreting results of previous studies. A standardised use of terms should be encouraged in CSVD research. These CSVD features have long been regarded as different lesions, but emerging evidence has indicated that they might share some common intrinsic microvascular pathologies and therefore, owing to its diffuse nature, CSVD should be regarded as a 'whole-brain disease'. Single antiplatelet (for acute lacunar ischaemic stroke) and management of traditional risk factors still remain the most important therapeutic and preventive approach, due to limited understanding of pathophysiology in CSVD. Increasing evidence suggests that new studies should consider drugs that target endothelium and blood-brain barrier to prevent and treat CSVD. Epidemiology of CSVD might differ in Asian compared with Western populations (where most results and guidelines about CSVD and stroke originate), but more community-based data and clear stratification of stroke types are required to address this.

Markers of cerebral small vessel disease and severity of depression in the general population

The vascular depression hypothesis postulates that cerebral small vessel disease can cause or exacerbate depression in elderly persons. Numerous studies explored the association of imaging markers of cerebral small vessel disease including white matter lesions (WMLs) and lacunar infarcts with depressive symptoms or disorders. However, cerebral microbleeds have not been tested in depression. In the current study, we aimed to explore the association of WMLs, lacunar infarcts and cerebral microbleeds with depression continuum in a large population-based sample, the Rotterdam Study. Study population consisted of 3799 participants (aged 45 or over) free of dementia. WML volumes, lacunar infarcts and cerebral microbleeds were measured with brain magnetic resonance imaging. Depressive symptoms, depressive disorders and co-morbid anxiety disorders were assessed with validated questionnaires and clinical interview. WML volumes and lacunar infarcts were associated with depressive symptoms and disorders. Cerebral microbleeds, especially in deep or infratentorial brain regions, were related to depressive disorders only. Our results indicate that WMLs and lacunar infarcts might be non-specific vascular lesions seen in depressive symptoms and disorders. Association of cerebral microbleeds with more severe forms of depression may indicate impaired brain iron homeostasis or minor episodes of cerebrovascular extraversion, which may play a role in depression etiology.

The Effect of Pulsatility Index on Infarct Volume in Acute Lacunar Stroke

PURPOSE

Lacunar stroke, in the context of small vessel disease, is a type of cerebral infarction caused by occlusion of a penetrating artery. Pulsatility index (PI) is an easily measurable parameter in Transcranial Doppler ultrasound (TCD) study. PI reflects distal cerebral vascular resistance and has been interpreted as a surrogate marker of small vessel disease. We hypothesized that an increased PI, a marker of small vessel disease, might be associated with a larger infarct volume in acute lacunar stroke.

MATERIALS AND METHODS

This study included 64 patients with acute lacunar stroke who underwent TCD and brain MRI. We evaluated the association between the mean PI value of bilateral middle cerebral arteries and infarct volume on diffusion-weighted MRI using univariate and multivariate linear regression.

RESULTS

The mean infarct volume and PI were 482.18±406.40 mm³ and 0.86±0.18, respectively. On univariate linear regression, there was a significant positive association between PI and infarct volume (p=0.001). In the multivariate model, a single standard deviation increase of PI (per 0.18) was associated with an increase of 139.05 mm³ in infarct volume (95% confidence interval, 21.25 to 256.85; p=0.022).

CONCLUSION

We demonstrated that PI was an independent determinant of infarct volume in acute lacunar stroke. The PI value measured in acute stroke may be a surrogate marker of the extent of ischemic injury.

Correlation of matrix metalloproteinase-2 single nucleotide polymorphisms with the risk of small vessel disease (SVD)

BACKGROUND

Maladjustment of matrix metalloproteinases (MMPs) results in cerebral vasculature and blood-brain barrier dysfunction, which is associated with small vessel disease (SVD). This study was to aim at evaluating correlations between matrix metalloproteinase-2 and 9 single nucleotide polymorphisms and the risk of SVD.

METHODS

A total of 178 patients with SVD were enrolled into this study via Nanjing Stroke Registry Program (NSRP) from January 2010 to November 2011. SVD patients were further subtyped as isolated lacunar infarction (ILI, absent or with mild leukoaraiosis) and ischemic leukoaraiosis (ILA, with moderate or severe leukoaraiosis) according to the Fazekas scale. 100 age- and gender-matched individuals from outpatient medical examination were recruited as the control group. The genotypes of MMP-2-1306 T/C and MMP-9-1562 C/T were determined by the TaqMan method.

RESULTS

Of 178 SVD patients, 86 and 92 patients were classified as ILI and ILA, respectively. Comparison analysis between SVD patients and controls revealed a significant correlation between SVD and hypertension, as well as a prevalence of hypertension in ILA. Further genotype analysis showed that the frequency of MMP-2-1306 CC genotype was higher in ILA patients than in controls (P=0.009, χ(2) test; P=0.027, the multiple test with Bonferroni correction). Finally, logistic regression analysis with adjustment of age, sex and vascular risk factors showed that the MMP-2-1306 T/C polymorphism was an independent predictor for ILA (OR: 2.605; 95% confidence interval [CI], 1.067-6.364; P=0.036).

CONCLUSION

Our findings suggest that the MMP-2-1306 T/C polymorphism is a direct risk factor for ILA.

[Concept, pathophysiology and treatment for branch atheromatous disease]

Small deep brain infarcts are often caused by two different vascular pathologies: 1. atheromatous occlusion at the orifice of large caliber penetrating arteries termed branch atheromatous disease (BAD) and 2. lipohyallinotic degenerative changes within the course of penetrating arteries termed lipohyalinitic degeneration. Representative vascular territories of BAD type infarcts are lenticulostriate artery (LSA), pontine paremedian artery (PPA) and less frequently anterior choroidal artery. BAD type infarcts are strongly associated with progressive motor deficits (PMD) leading to a worse functional outcome, because they affect pyramidal tract at corona radiata, pontine base or internal capsule. In our study, female sex and initial severity of motor deficits were common predictors for PMD in both groups with LSA and PPA. Single infarcts without concomitant silent lacunar infarcts and preceding lacunar transient ischemic attack (TIA) in the LSA group, and diabetes mellitus in the PPA group were independent predictors for PMD in penetrating artery infarctions. There were different characteristics between the groups of LSA and PPA. Prevalence of male gender, diabetes mellitus and intracranial atherosclerosis were significantly higher in the PPA group than in the LSA group. The combined treatment of cilostazol and edarabone significantly improved functional outcome especially in the PPA infarct group. Adjoining clopidgrel on aforementioned combined treatment further improved functional outcome in the LSA group. The actions of vasodilatation and endothelial protection in cilostazol and inhibition of shear-induced platelet activation in clopidogrel, as well as scavenging free radicals in edaravone might work effectively.

Antiplatelet and anticoagulant therapy after intracerebral hemorrhage

Management of patients with an indication for long-term oral antithrombotic therapy who have an intracerebral hemorrhage (ICH) presents a therapeutic dilemma. Should antithrombotic therapy be resumed, and if so, when, using what agent, and for whom? There is no consensus for answers to these questions. In the absence of randomized trials, management of antithrombotic therapy after ICH is based on a combination of observational data, pathophysiologic concepts, and decision analysis. At the heart of the decision is an assessment of the individual patient's risk of thromboembolism off antithrombotic therapy versus risk of ICH recurrence on antithrombotic therapy.

Clinical correlates of infarct shape and volume in lacunar strokes: the Secondary Prevention of Small Subcortical Strokes trial

BACKGROUND AND PURPOSE

Infarct size and location are thought to correlate with different mechanisms of lacunar infarcts. We examined the relationship between the size and shape of lacunar infarcts and vascular risk factors and outcomes.

METHODS

We studied 1679 participants in the Secondary Prevention of Small Subcortical Stroke trial with a lacunar infarct visualized on diffusion-weighted imaging. Infarct volume was measured planimetrically, and shape was classified based on visual analysis after 3-dimensional reconstruction of axial MRI slices.

RESULTS

Infarct shape was ovoid/spheroid in 63%, slab in 12%, stick in 7%, and multicomponent in 17%. Median infarct volume was smallest in ovoid/spheroid relative to other shapes: 0.46, 0.65, 0.54, and 0.90 mL, respectively (P<0.001). Distributions of vascular risk factors were similar across the 4 groups except that patients in the ovoid/spheroid and stick groups were more often diabetic and those with multicomponent had significantly higher blood pressure at study entry. Intracranial stenosis did not differ among groups (P=0.2). Infarct volume was not associated with vascular risk factors. Increased volume was associated with worse functional status at baseline and 3 months. Overall, 162 recurrent strokes occurred during an average of 3.4 years of follow-up with no difference in recurrent ischemic stroke rate by shape or volume.

CONCLUSIONS

In patients with recent lacunar stroke, vascular risk factor profile was similar among the different infarct shapes and sizes. Infarct size correlated with worse short-term functional outcome. Neither shape nor volume was predictive of stroke recurrence.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

Predictors of neurologic deterioration in patients with small-vessel occlusion and infarcts in the territory of perforating arteries

BACKGROUND

It is difficult to predict neurologic deterioration in patients with small-vessel occlusion (SVO), that is, small infarcts in the territory of cerebral perforating arteries.

METHODS

We reviewed 110 patients with SVO who were admitted to our hospital. We divided them into groups with (n = 32, group 1) and without deterioration (n = 78, group 2) and evaluated their medical records, risk factors, magnetic resonance imaging findings, grade of periventricular hyperintensity (PVH), maximum diameter of the infarct area, and the number of slices showing infarcts on diffusion-weighted images (DWI).

RESULTS

Our study population consisted of 110 patients (71 males and 39 females; mean age 69.2 years): 32 (29%) did and 78 (71%) did not suffer deterioration. By univariate analysis, the age, current smoking, history of stroke, maximum diameter of the infarcted area, number of DWI slices with infarcts, frequency of PVH, and PVH grade based on Fazekas classification differed significantly between the 2 groups. By multivariate analysis, conventional risk factors other than PVH and history of stroke were not associated with neurologic deterioration (PVH grade ≥ 2 versus PVH grade ≤ 1, odds ratio 6.72, P = .006; with stroke versus without stroke, odds ratio .21, P = .049). We also found that higher the PVH grade, the worse the National Institutes of Health Stroke Scale score at the time of discharge.

CONCLUSIONS

PVH and without history of stroke are independently associated with neurologic deterioration in patients with SVO.

Predictors of stroke recurrence in patients with recent lacunar stroke and response to interventions according to risk status: secondary prevention of small subcortical strokes trial

BACKGROUND

Among participants in the Secondary Prevention of Small Subcortical Strokes randomized trial, we sought to identify patients with high versus low rates of recurrent ischemic stroke and to assess effects of aggressive blood pressure control and dual antiplatelet therapy according to risk status.

METHODS

Multivariable analyses of 3020 participants with recent magnetic resonance imaging-defined lacunar strokes followed for a mean of 3.7 years with 243 recurrent ischemic strokes.

RESULTS

Prior symptomatic lacunar stroke or transient ischemic attack (TIA) (hazard ratio [HR] 2.2, 95% confidence interval [CI] 1.6, 2.9), diabetes (HR 2.0, 95% CI 1.5, 2.5), black race (HR 1.7, 95% CI 1.3, 2.3), and male sex (HR 1.5, 95% CI 1.1, 1.9) were each independently predictive of recurrent ischemic stroke. Recurrent ischemic stroke occurred at a rate of 4.3% per year (95% CI 3.4, 5.5) in patients with prior symptomatic lacunar stroke or TIA (15% of the cohort), 3.1% per year (95% CI 2.6, 3.9) in those with more than 1 of the other 3 risk factors (27% of the cohort), and 1.3% per year (95% CI 1.0, 1.7) in those with 0-1 risk factors (58% of the cohort). There were no significant interactions between treatment effects and stroke risk status.

CONCLUSIONS

In this large, carefully followed cohort of patients with recent lacunar stroke and aggressive blood pressure management, prior symptomatic lacunar ischemia, diabetes, black race, and male sex independently predicted ischemic stroke recurrence. The effects of blood pressure targets and dual antiplatelet therapy were similar across the spectrum of independent risk factors and recurrence risk.

Association of sleep apnea with clinically silent microvascular brain tissue changes in acute cerebral ischemia

The aim of this study was to determine the importance of sleep apnea in relation to clinically silent microvascular brain tissue changes in patients with acute cerebral ischemia. Patients with acute cerebral ischemia prospectively underwent nocturnal respiratory polygraphy within 5 days from symptom-onset. Sleep apnea was defined as apnea-hypopnea-index (AHI) ≥5/h. Experienced readers blinded to clinical and sleep-related data reviewed brain computed tomography and magnetic resonance imaging scans for leukoaraiosis and chronic lacunar infarctions. Ischemic lesions were considered clinically silent when patients did not recall associated stroke-like symptoms. Functional outcome was assessed with modified Rankin Scale at discharge, 6 and 12 months. Fifty-one of 56 (91 %) patients had sleep apnea of any degree. Patients with moderate-to-severe leukoaraiosis (Wahlund score ≥5) were found to have higher mean AHI than those with none or mild leukoaraiosis (34.4 vs. 12.8/h, p < 0.001). Moderate-to-severe sleep apnea (AHI ≥15/h) was found to be an independent predictor of moderate-to-severe leukoaraiosis (adjusted OR 6.03, 95 % CI 1.76-20.6, p = 0.0042) and of moderate-to-severe leukoaraiosis associated with clinically silent chronic lacunar infarctions (adjusted OR 10.5, 95 % CI 2.19-50.6, p = 0.003). The higher the Wahlund score and the AHI, the more likely unfavorable functional outcome resulted over time (p = 0.0373). In acute cerebral ischemia, sleep apnea is associated with clinically silent microvascular brain tissue changes and may negatively influence functional outcome. Routine sleep apnea screening and further investigation of possible long-term effects of non-invasive ventilatory treatment of sleep apnea appear warranted in this at-risk population.

Accumulation of MRI Markers of Cerebral Small Vessel Disease is Associated with Decreased Cognitive Function. A Study in First-Ever Lacunar Stroke and Hypertensive Patients

Background: White matter lesions (WMLs), asymptomatic lacunar infarcts, brain microbleeds (BMBs), and enlarged perivascular spaces (EPVS) have been identified as silent lesions due to cerebral small vessel disease (cSVD). All these markers have been individually linked to cognitive functioning, but are also strongly correlated with each other. The combined effect of these markers on cognitive function has never been studied and would possibly provide more useful information on the effect on cognitive function.

Methods: Brain MRI and extensive neuropsychological assessment were performed in 189 patients at risk for cSVD (112 hypertensive patients and 77 first-ever lacunar stroke patients). We rated the presence of any asymptomatic lacunar infarct, extensive WMLs, any deep BMB, and moderate to extensive EPVS in the basal ganglia. The presence of each marker was summed to an ordinal score between 0 and 4. Associations with domains of cognitive function (memory, executive function, information processing speed, and overall cognition) were analyzed with correlation analyses.

Results: Correlation analyses revealed significant associations between accumulating cSVD burden and decreased performance on all cognitive domains (all p ≤ 0.001). Results remained significant for information processing speed (r = −0.181, p = 0.013) and overall cognition (r = −0.178, p = 0.017), after correction for age and sex. Testing of trend using linear regression analyses revealed the same results.

Discussion: We tested a new approach to capture total brain damage resulting from cSVD and found that accumulation of MRI burden of cSVD is associated with decreased performance on tests of information processing speed and overall cognition, implying that accumulating brain damage is accompanied by worse cognitive functioning.

Mechanisms of sporadic cerebral small vessel disease: insights from neuroimaging

The term cerebral small vessel disease (SVD) describes a range of neuroimaging, pathological, and associated clinical features. Clinical features range from none, to discrete focal neurological symptoms (eg, stroke), to insidious global neurological dysfunction and dementia. The burden on public health is substantial. The pathogenesis of SVD is largely unknown. Although the pathological processes leading to the arteriolar disease are associated with vascular risk factors and are believed to result from an intrinsic cerebral arteriolar occlusive disease, little is known about how these processes result in brain disease, how SVD lesions contribute to neurological or cognitive symptoms, and the association with risk factors. Pathology often shows end-stage disease, which makes identification of the earliest stages difficult. Neuroimaging provides considerable insights; although the small vessels are not easily seen themselves, the effects of their malfunction on the brain can be tracked with detailed brain imaging. We discuss potential mechanisms, detectable with neuroimaging, that might better fit the available evidence and provide testable hypotheses for future study.

Two different clinical entities of small vessel occlusion in TOAST classification

BACKGROUND

Small deep infarcts might be classified into 2 types: lacunar and branchatheromatous infarcts. However, since their initial description, small deep infarcts were still regarded as the same category of the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, small vessel occlusion (SVO). We hypothesized that the 2 types of small deep infarcts would be distinct clinical entities. This study was conducted to investigate the clinical characteristics in the 2 groups of patients according to lesion pattern and combined atherosclerotic diseases.

METHODS

We included patients with small deep infarcts in the subcortical area. The patients were divided into 2 groups: (1) island lesions and (2) linear lesions on coronal diffusion weighted imaging. The status of the relevant artery was categorized as no stenosis, non-significant (<50% of luminal narrowing) and significant (≥ 50% of luminal narrowing). We compared the clinical and imaging characteristics of two lesion types according to various arterial status.

RESULTS

This study analyzed a total of 248 patients. Independent factors for island lesions on coronal DWI were male, severe leukoaraiosis, microbleeds, abnormal glycated hemoglobin (HbA1C), and abnormal estimated glomerular filtration ratio (eGFR) adjusted by age, sex, and initial National Institutes of Health Stroke Scale. In addition, in patients without significant relevant arterial stenosis, island lesion patterns were more frequently associated with severe periventricular white matter hyperintensity, diabetes mellitus, abnormal eGFR and abnormal HbA1C than linear lesion patterns.

CONCLUSION

This study demonstrated that SVO of TOAST classifications had different imaging and clinical characteristics according to the lesion patterns of coronal imaging. It suggests that two types of SVO should be regarded as the different categories of stroke classification.

The association between small vessel infarcts and the activities of amyloid-β peptide degrading proteases in apolipoprotein E4 allele carriers

Small vessel (SV) and large vessel (LV) brain infarcts are distinct pathologies. Using a homebound elderly sample, the numbers of either infarct subtypes were similar between those apolipoprotein E4 allele (ApoE4) carriers (n = 80) and noncarriers (n = 243). We found that the higher the number of SV infarcts, but not LV infarcts, a participant had, the higher the activity of substrate V degradation in serum especially among ApoE4 carriers (β = +0.154, SE = 0.031, P < .0001) after adjusting for the confounders. Since substrate V degradation could be mediated by insulin-degrading enzyme (IDE) or/and angiotensin-converting enzyme (ACE), but no relationship was found between SV infarcts and specific ACE activities, blood IDE may be a useful biomarker to distinguish the brain infarct subtypes. Insulin-degrading enzyme in blood may also imply an important biomarker and a pathological event in Alzheimer disease through SV infarcts in the presence of ApoE4.

Risk reduction strategies in ischaemic stroke : the role of antiplatelet therapy

Stroke is a common and serious disorder, and is a leading cause of disability and death in adults. Transient ischaemic attacks are now recognised as being common precursors of stroke, with a high risk of subsequent vascular events. The majority of strokes are ischaemic in origin, and are typically due to athero-thrombosis/microatheromatosis involving a large or small cerebral blood vessel or to an embolic event. Owing to the diffuse nature of atherothrombosis, these patients are at risk of ischaemic events in other vascular beds. Options for treating patients with acute ischaemic stroke are very limited; therefore prevention is a key strategy for reducing the risk of recurrent stroke and other vascular events. Treatment of risk factors such as hypertension, diabetes mellitus, smoking and obesity is an important approach for stroke prevention. Platelets are involved in the development of thrombi and emboli, making antiplatelet therapy an important preventive strategy. Antiplatelet agents are effective in preventing recurrent ischaemic stroke and other vascular ischaemic events, such as myocardial infarction and vascular death. In some cases, anticoagulants may be effective in preventing ischaemic stroke recurrence. Carotid endarterectomy can reduce stroke risk in patients with moderate- or high-grade carotid artery stenosis. Choosing the most appropriate therapy for the individual patient is key to optimising stroke prevention.

Small vessel cerebrovascular disease: the past, present, and future

Brain infarction due to small vessel cerebrovascular disease (SVCD)-also known as small vessel infarct (SVI) or "lacunar" stroke-accounts for 20% to 25% of all ischemic strokes. Historically, SVIs have been associated with a favorable short-term prognosis. However, studies over the years have demonstrated that SVCD/SVI is perhaps a more complex and less benign phenomenon than generally presumed. The currently employed diagnostic and therapeutic strategies are based upon historical and contemporary perceptions of SVCD/SVI. What is discovered in the future will unmask the true countenance of SVCD/SVI and help furnish more accurate prognostication schemes and effective treatments for this condition. This paper is an overview of SVCD/SVI with respect to the discoveries of the past, what is known now, and what will the ongoing investigations evince in the future.

Risk factors for lacune subtypes in the Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVE

Lacunar infarctions are mainly due to 2 microvascular pathologies: lipohyalinosis and microatheroma. Little is known about risk factor differences for these subtypes. We hypothesized that diabetes and glycated hemoglobin (HbA(1)c) would be related preferentially to the lipohyalinotic subtype.

METHODS

We performed a cross-section analysis of the brain MRI data from 1,827 participants in the Atherosclerosis Risk in Communities study. We divided subcortical lesions ≤ 20 mm in diameter into those ≤ 7 mm (of probable lipohyalinotic etiology) and 8-20 mm (probably due to microatheroma) and used Poisson regression to investigate associations with the number of each type of lesion. Unlike previous studies, we also fitted a model involving lesions <3 mm.

RESULTS

Age (prevalence ratio [PR] 1.11 per year; 95% confidence interval [CI] 1.08-1.14), black ethnicity (vs white, PR 1.66; 95% CI 1.27-2.16), hypertension (PR 2.12; 95% CI 1.61-2.79), diabetes (PR 1.42; 95% CI 1.08-1.87), and ever-smoking (PR 1.34; 95% CI 1.04-1.74) were significantly associated with lesions ≤ 7 mm. Findings were similar for lesions <3 mm. HbA(1)c, substituted for diabetes, was also associated with smaller lesions. Significantly associated with 8-20 mm lesions were age (PR 1.14; 95% CI 1.09-1.20), hypertension (PR 1.79; 95% CI 1.14-2.83), ever-smoking (PR 2.66; 95% CI 1.63-4.34), and low-density lipoprotein (LDL) cholesterol (PR 1.27 per SD; 95% CI 1.06-1.52). When we analyzed only participants with lesions, history of smoking (PR 1.99; 95% CI 1.23-3.20) and LDL (PR 1.33 per SD; 95% CI 1.08-1.65) were associated with lesions 8-20 mm.

CONCLUSIONS

Smaller lacunes (even those <3 mm) were associated with diabetes and HbA(1)c, and larger lacunes associated with LDL cholesterol, differences which support long-held theories relating to their underlying pathology. The findings may contribute to broader understanding of cerebral microvascular disease.

Cerebral small vessel disease and risk of death, ischemic stroke, and cardiac complications in patients with atherosclerotic disease: the Second Manifestations of ARTerial disease-Magnetic Resonance (SMART-MR) study

BACKGROUND AND PURPOSE

Cerebral small vessel disease may be related to vascular and nonvascular pathology. We assessed whether lacunar infarcts and white matter lesions on MRI increased the risk of vascular and nonvascular death and future vascular events in patients with atherosclerotic disease.

METHODS

Brain MRI was performed in 1309 patients with atherosclerotic disease from the Second Manifestations of ARTerial disease-Magnetic Resonance (SMART-MR) study. Infarcts were scored visually and volumetric assessment of white matter lesion was performed. Patients were followed for a median of 4.5 years (range, 0.2 to 7.1 years) for death, ischemic stroke, and ischemic cardiac complications.

RESULTS

Cox regression models showed that presence of lacunar infarcts (n=229) increased the risk of vascular (hazard ratio, 2.6; 95% CI, 1.4 to 4.9) and nonvascular death (hazard ratio, 2.7; 95% CI, 1.3 to 5.3), adjusted for age, sex, vascular risk factors, nonlacunar infarcts, and white matter lesion. These risks were similar for patients with silent lacunar infarcts. White matter lesion volume (relative to total intracranial volume) increased the risk of vascular death (hazard ratio per milliliter increase, 1.03; 95% CI, 1.01 to 1.05) and white matter lesions in the upper quintile compared with lower quintiles increased risk of ischemic stroke (hazard ratio, 2.6; 95% CI, 1.3 to 4.9).

CONCLUSIONS

Cerebral small vessel disease, with or without a history of cerebrovascular disease, is associated with increased risk of death and ischemic stroke in patients with atherosclerotic disease.

Correlations between left ventricular mass index and cerebrovascular lesion

Left ventricular (LV) mass and LV geometry are well-established measures of hypertension chronicity and severity, have a prognostic value on cardiovascular morbidity and mortality, and are related to asymptomatic cerebral small-artery disease (SAD) and largeartery disease (LAD). The aim of the present study was to clarify the different effects of LV mass and LV geometry on underlying SAD compared with its effects on underlying LAD in ischemic stroke patients. Four hundred three ischemic stroke patients underwent echocardiography to determine LV mass index and relative wall thickness. Brain magnetic resonance imaging, angiography, and carotid magnetic resonance angiography were preformed to detect LAD (≥50% stenosis) and SAD (leukoaraiosis, microbleeds, and old lacunar infarction) in the brain. Multivariate analyses showed that the LV mass index was highly associated with underlying SAD but not with underlying LAD. Among the various subtypes of SAD, only cerebral microbleeds were closely related to the LV mass index. Concentric LV hypertrophy was not related to the presence of either SAD or LAD. Subgroup analyses revealed that, among the various subtypes of SAD, only cerebral microbleeds were associated with concentric LV hypertrophy. In conclusion, cerebral microbleeds may imply more advanced target organ damage than underlying LAD and ischemic subtypes of SAD.

Vascular inflammation in cerebral small vessel disease

Cerebral small vessel disease (CSVD) is considered to be caused by an increased permeability of the blood-brain barrier and results in enlargement of Virchow Robin spaces (VRs), white matter lesions, brain microbleeds, and lacunar infarcts. The increased permeability of the blood-brain barrier may relate to endothelial cell activation and activated monocytes/macrophages. Therefore, we hypothesized that plasma markers of endothelial activation (adhesion molecules) and monocyte/macrophage activation (neopterin) relate to CSVD manifestations. In 163 first-ever lacunar stroke patients and 183 essential hypertensive patients, we assessed CSVD manifestations on brain magnetic resonance imaging (MRI) and levels of C-reactive protein (CRP), neopterin, as well as circulating soluble adhesion molecules (sICAM-1, sVCAM-1, sE-selectin, sP-selectin). Neopterin, sICAM-1 and sVCAM-1 levels were higher in patients with extensive CSVD manifestations than in those without (p < 0.01). Neopterin levels independently related to higher numbers of enlarged Virchow Robin spaces (p < 0.001). An inflammatory process with activated monocytes/macrophages may play a role in the increased permeability of the blood brain barrier in patients with CSVD.

Family history of stroke is an independent risk factor for lacunar stroke subtype with asymptomatic lacunar infarcts at younger ages

BACKGROUND AND PURPOSE

Results from case-control and case-case studies indicate that a positive family history of stroke (FHstroke) is an independent risk factor for lacunar stroke. Different lacunar stroke phenotypes can be distinguished on the basis of the presence of asymptomatic lacunar infarcts (aLACs), ischemic white-matter lesions, or brain microbleeds. The aim of the present study was to determine whether familial aggregation of stroke was different for lacunar stroke phenotypes.

METHODS

In 157 patients with a first-ever lacunar stroke, a complete first-degree FHstroke was obtained by a standardized questionnaire and additional interview. Lacunar stroke patients were categorized successively into groups, depending on the presence of aLACs, ischemic white-matter lesions, and brain microbleeds on magnetic resonance imaging.

RESULTS

Fifty-two percent of patients reported a positive FHstroke in at least one of their first-degree relatives. In younger (<65 years) probands, a high frequency of parental FHstroke (59% versus 20%, P<0.01) in those with aLACs compared with probands without aLACs was found. In multivariate analysis, the strongest associations were found for parental FHstroke (odds ratio=6.46; 95% CI=1.96 to 21.33), maternal FHstroke (odds ratio=4.00; 95% CI=1.18 to 13.56), and paternal FHstroke (odds ratio=5.40; 95% CI=1.14 to 25.61).

CONCLUSIONS

A family history of stroke might be an independent risk factor for the lacunar stroke phenotype with aLACs at younger ages, suggesting a role for genetic factors in this phenotype caused by diffuse vasculopathy.

Differing risk factors and outcomes in ischemic stroke subtypes: focus on lacunar stroke

Lacunar stroke has been a recognized stroke subtype for many years but its pathophysiology remains unknown, so prevention and treatment are suboptimal. Most lacunar strokes result from an intrinsic cerebral small vessel disease, probably part of a systemic disorder. Hypertension, diabetes and other vascular risk factors (but not atrial fibrillation and ipsilateral carotid stenosis) are equally common in lacunar as in large artery atherothromboembolic stroke, which, together with other factors, suggests that the patient’s response to vascular risk factors, not the vascular risk factors per se, determines whether they develop small vessel or large artery stroke. Inflammation and endothelial failure are probably involved in the pathogenesis of lacunar stroke, but their role needs to be clarified. The cerebral venules as well as arterioles are abnormal in this condition. The disorder may not be primarily ischemic; instead, arteriolar thrombosis may be a late-stage phenomenon secondary to chronic arteriolar wall damage resulting from leakage of plasma components across the BBB. Accurate diagnosis of lacunar stroke, avoiding risk factor-based classifications, is required to underpin future research.

The correlation between carotid siphon calcification and lacunar infarction

INTRODUCTION

The aim of this study was to evaluate the correlation between carotid siphon (CS) calcification and lacunar infarction caused by small-vessel disease.

METHODS

This retrospective study included 445 patients (M/F = 256:189) older than 40 years (mean age 60.0 ± 12.3 years, range 41-98 years) without large intracranial lesions who had undergone both brain CT and MRI within an interval of 6 months. The patients were classified into three groups according to the number of lacunar infarctions: group I-zero infarctions (n = 328), group II-one to three infarctions (n = 94), and group III-four or more infarctions (n = 23). The severity of CS calcification was evaluated on CT and scored on a five-point scale (0-none, 1-stippled, 2-thin continuous or thick discontinuous, 3-thick continuous, 4-double tracts), and the calcification scores on both sides were summed. An ANOVA test was used to compare calcification scores among the three groups, and a logistic regression test was used to evaluate the influence of CS calcification and known cerebrovascular risk factors on the occurrence of lacunar infarction.

RESULTS

On the ANOVA test, total calcification scores were significantly different among the three groups (group I = 1.28 ± 1.99, group II = 3.31 ± 2.39, group III = 4.36 ± 2.08; P < 0.05). Higher rates of lacunar infarction were associated with higher CS calcification scores. On the logistic regression test, CS calcification, age, and hypertension were significant risk factors for lacunar infarction (P < 0.05).

CONCLUSION

CS calcification was correlated with the occurrence of lacunar infarction. The degree of CS calcification may be used to predict the possibility of a future lacunar infarction.

Autoantibodies against oxidized low-density lipoprotein in cerebral small vessel disease

BACKGROUND AND PURPOSE

Oxidized low-density lipoprotein (oxLDL) induces endothelial dysfunction and antibody formation. Because endothelial dysfunction is involved in cerebral small vessel disease (CSVD) (dilated Virchow Robin spaces, lacunar infarcts, and white matter lesions), oxLDL antibodies could play a role in CSVD pathogenesis. Therefore, we studied oxLDL antibodies in patients with high prevalence of CSVD: lacunar stroke patients and essential hypertensive patients.

METHODS

A total of 158 lacunar stroke patients, 158 hypertensive patients, and 43 healthy controls were included. We determined levels of IgG and IgM against hypochlorite (HOCl) and malondialdehyde (MDA) oxLDL using ELISA (values in optical density).

RESULTS

Patients with CSVD had higher levels of IgG-HOCl-oxLDL (0.77 versus 0.70; P<0.01), as well as lower levels of IgM-MDA-oxLDL (0.55 versus 0.65; P<0.05) than patients without such lesions. Higher IgG-HOCl-oxLDL levels were only independently associated with higher numbers of Virchow Robin spaces at the level of the basal ganglia (β=0.218; P<0.001).

CONCLUSIONS

An autoinflammatory process with lower levels of IgM antibodies and higher levels of IgG antibodies against oxLDL may be involved in CSVD.