Carotid artery intima-media thickness associated with prognosis of intracranial branch atheromatous disease.

BACKGROUND AND PURPOSE: Small deep brain infarcts are often caused by two different vascular pathologies: branch atheromatous disease (BAD) and lipohyalinotic degeneration (LD). In this study, we compare the clinical characteristics of BAD and LD and investigate the role of C-reactive protein (CRP), homocysteine (Hcy), and carotid artery intima-media thickness (IMT) in the prognosis of patients with BAD and LD. METHODS: Of 262 adult patients with small deep infarcts, 104 were considered BAD and 158 were considered LD. Data compared included clinical information, prevalence of lacune and leukoaraiosis, Hcy, CRP, carotid artery IMT, deterioration during admission, and recurrence of ischemic stroke (IS) within 1 year. RESULTS: Patients with LD have severe leukoaraiosis and higher prevalence of lacune and intracerebral hemorrhage compared with those with BAD. Patients with BAD have higher initial National Institutes of Health Stroke Scale scores and incidence of progressive motor deficits compared with those with LD; CRP is associated with the progression in both groups. There is no statistical difference of recurring risk of IS within 1 year between the two groups; by multivariable logistic regression analysis, carotid artery IMT was an independent risk factor for recurrence of IS in 1 year in patients with BAD. CONCLUSION: BAD as an independent clinical entity has different clinical and radiological characteristics compared with LD. Carotid artery IMT is an independent risk factor for recurrence of IS in patients with BAD.

Association between non-high-density-lipoprotein-cholesterol levels and the prevalence of asymptomatic intracranial arterial stenosis.

OBJECTIVE: The aim of this study was to assess the association between non-high-density-lipoprotein-cholesterol (non-HDL-C) and the prevalence of asymptomatic intracranial arterial stenosis (ICAS). METHODS AND RESULTS: The Asymptomatic Polyvascular Abnormalities Community (APAC) study is a prospective cohort study based on the Kailuan district (China) population. A total of 5351 eligible subjects, aged ≥40, and without history of stroke or myocardial infarction, were enrolled in this study. Transcranial Doppler Ultrasonography (TCD) was performed on all enrolled subjects for the evaluation of ICAS presence. Out of 5351 patients, 698 subjects showed evidence of ICAS (prevalence of 13.04%). Multivariate analysis showed that non-HDL-C is an independent indicator for the presence of ICAS (OR  = 1.15, 95%CI: 1.08 - 1.23), but with a gender difference (P for interaction<0.01): in men, non-HDL-C is an independent indicator for ICAS (multivariate-adjusted OR  = 1.28, 95%CI: 1.18-1.39), but not in women (multivariate-adjusted OR  = 1.03, 95%CI: 0.93-1.14). Subjects were divided into five subgroups based non-HDL-C levels and these levels correlated linearly with the prevalence of ICAS (P for trend <0.01). Compared with the first quintile, multivariate-adjusted OR (95%CI) of the second, third, fourth and fifth quintiles were: 1.05 (0.71-1.56), 1.33 (0.91-1.95), 1.83 (1.27-2.63), 2.48 (1.72-3.57), respectively. CONCLUSION: Non-HDL-C is an independent predictor of ICAS prevalence in men but not in women, suggesting that non-HDL-C levels could be used as a surveillance factor in the primary prevention of ischemic stroke, especially in men.

Intracranial arterial calcification is highly prevalent in hemodialysis patients but does not associate with acute ischemic stroke.

Intracranial arterial calcification (IAC) is associated with ischemic stroke in the general population but this relationship has not been examined in hemodialysis patients. We examined the factors associated with IAC and its relationship with acute ischemic stroke in this population. We retrospectively studied 490 head computed tomographic scans from 2225 hemodialysis patients presenting with neurological symptoms at our center (October 2005-May 2009). Intracranial arterial calcification was graded using a validated scoring system. Multivariate regression was used to examine the factors associated with the presence of IAC, its severity, and its ability to predict acute ischemic stroke. Weibull's survival models analyzed the relationship between IAC severity and survival. Ninety-five percent of patients with ischemic stroke had IAC vs. 83% in the nonstroke group (P=0.02). Intracranial arterial calcification severity increased with age (P<0.001), hemodialysis vintage (P<0.001), serum phosphate (P<0.05), and major comorbidities. In patients with multiple computed tomographic scans during the study period, increased IAC severity at baseline was predictive of acute ischemic stroke (P=0.05) on logistic regression analysis. High-grade and not low-grade IAC was associated with worse survival (P=0.008). Intracranial arterial calcification is highly prevalent in hemodialysis patients, especially in those with acute ischemic stroke. Its severity is prognostically significant and associated with risk factors for vascular calcification and may confer a greater risk of acute ischemic stroke. The mechanisms underlying the high incidence of ischemic stroke in this patient group require further comprehensive study.

Central benzodiazepine receptor binding potential and CBF images on SPECT correlate with oxygen extraction fraction images on PET in the cerebral cortex with unilateral major cerebral artery occlusive disease.

UNLABELLED: Oxygen extraction fraction (OEF) is a key predictor of stroke recurrence in patients with symptomatic major cerebral arterial occlusive disease. The purpose of the present study was to compare central benzodiazepine receptor binding potential (BRBP) and cerebral blood flow (CBF) images on SPECT with OEF images on PET in patients with chronic unilateral middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease. METHODS: OEF, CBF, and BRBP were assessed using (15)O PET and N-isopropyl-p-(123)I-iodoamphetamine and (123)I-iomazenil SPECT, respectively, in 20 healthy subjects and in 34 patients with unilateral MCA or ICA occlusive disease. All images were transformed into the standard brain size and shape by linear and nonlinear transformation using statistical parametric mapping for anatomic standardization. A region of interest (ROI) was automatically placed according to the arterial supply using a 3-dimensional stereotactic ROI template, and the ratio of the value in the affected side to that in the contralateral side was calculated in each image. RESULTS: Among patients with occlusive disease, a significant positive correlation was observed between PET OEF and SPECT BRBP/CBF ratios in 3 cerebral cortical regions (r = 0.851, P < 0.0001, for anterior cerebral artery [ACA] ROI; r = 0.807, P < 0.0001, for MCA ROI; and r = 0.774, P < 0.0001, for posterior cerebral artery [PCA] ROI), but there were no correlations between these 2 parameters in the basal ganglia or the cerebellum. When an abnormally elevated PET OEF ratio was defined as a value greater than the mean + 2 SDs obtained in healthy subjects, sensitivity and specificity were, respectively, 100% and 96% for the ACA ROI, 100% and 89% for the MCA ROI, and 100% and 93% for the PCA ROI for the SPECT BRBP/CBF ratio for detecting an abnormally elevated PET OEF ratio. CONCLUSION: BRBP/CBF images on SPECT correlate with OEF images on PET in a specific clinical setting-that is, in the cerebral cortex of patients with chronic unilateral MCA or ICA occlusive disease.

Clinical and biochemical diagnosis of small-vessel disease in acute ischemic stroke.

BACKGROUND AND PURPOSE: Both from clinical and research standpoints, it may be highly relevant to differentiate between small-artery and large-artery infarction in the acute phase of ischemic stroke. We conducted a study on the added value of two D-dimer assays over clinical assessment for diagnosis of lacunar infarction. METHODS: Clinical evaluation using the Oxfordshire Community Stroke Project (OCSP) classification and measurement of plasma D-dimer levels by the VIDAS D-dimer test (VIDAS) and the Triage Stroke Panel (TSP) were performed in 128 patients with ischemic stroke presenting within 9 h after onset of symptoms. The stroke subtype was defined as small-artery or large-artery infarction based on the TOAST classification. RESULTS: The overall accuracy for diagnosing of acute lacunar stroke using the OCSP classification, VIDAS (cut point for D-dimer 445 ng/mL) or TSP (cut point 300 ng/mL) was 89%, 88% and 87% respectively (P<0.001). The conjunctive use of the OCSP classification and VIDAS or TSP improved the accuracy to 97% and 98% respectively (P<0.001). The kappa coefficient for agreement between the two assays was acceptable (kappa, 0.64). These results were reproducible in subgroups of patients presenting within 4.5 h and within 6 h after onset of stroke symptoms. CONCLUSIONS: Diagnosis of acute lacunar infarction can reliably be made, based on the conjunctive use of clinical evaluation and measurement of D-dimer levels either by a standard assay or by a bedside testing kit.

Role of oxidative stress on pathogenesis of hypertensive cerebrovascular lesions.

The hypertensive rat brain exhibited softening, severe edema and intracerebral hemorrhage. The NO(2) (-) + NO(3) (-) (NOx) level in the hypertensive rat brain was higher than in the normotensive rat brain. Light microscopy demonstrated severe arterial and arteriolar lesions with fibrinoid deposits and medial lesion. After injecting hypertensive rats with nitroblue tetrazolium (NBT), formazan deposits, which are the reaction product of reduction of NBT by superoxide, were observed in the microvessels and nervous tissue around the microvessels of injured brain. Immunohistochemistry showed that copper zinc superoxide dismutase and manganese superoxide dismutase expression of the endothelial cells of hypertensive rats were also upregulated in comparison with normotensive rat endothelial cells. Inducible nitric oxide synthase and endothelial nitric oxide synthase expression in endothelial cells of normotensive rats were strongly positive, whereas the expression in hypertensive rat endothelial cells was weaker. Nitrotyrosine, a biomarker of peroxynitrite, which is a powerful oxidant formed by the reaction of nitric oxide (NO) with superoxide, was found in the microvessels, injured arteries and arterioles and infarcted brain tissue. Deposition of a major aldehydic product of lipid peroxidation, that is, 4-hydroxy-2-nonenal (4-HNE) was found in microvessels, perivascular tissue, and edematous and infarcted brain. Hypertensive cerebrovascular disease is the result of hypertension-induced oxidative stress.