Coexisting Carotid Atherosclerosis in Patients with Intracranial Small- or Large-Vessel Disease

Background and Purpose

The coexistence of carotid atherosclerosis in ischemic stroke patients with small-vessel disease (SVD) or intracranial large-vessel disease (ICLVD) was investigated using carotid duplex ultrasonography, and whether its coexistence affected the clinical prognosis was determined.

Methods

Ischemic stroke patients with SVD or ICLVD were enrolled (n=103). Risk factors, demographic data, and National Institutes of Health Stroke Scale (NIHSS) scores were obtained for all of the subjects. Early neurological progression was defined by an increase in NIHSS score during the first 7 days. Carotid ultrasonography was performed to measure the intima-media thickness (IMT) and carotid plaques.

Results

Among the 103 patients who were retrospectively enrolled in this study (56 with SVD and 47 with ICLVD), 66 (64.1%) had an atherosclerotic plaque and 23 (22.3%) had increased IMT. Increased IMT was observed more frequently in ICLVD than in SVD [15/47 (31.9%) vs. 8/56 (14.3%), p=0.032]. An atherosclerotic plaque was observed on subsequent carotid ultrasonographic examination in 28 (50%) of the 56 patients whose computed tomography angiography scans of the neck vessels were interpreted as normal. There was no association between presence of atherosclerotic change and early neurologic progression (p=0.94).

Conclusions

A coexisting atherosclerotic plaque or increased IMT was observed in 71.8% of patients with SVD or ICLVD. Whether the coexistence of carotid atherosclerotic change with either of these conditions affects the clinical prognosis remains to be elucidated.     

��-Fibrinogen Gene -455 G/A Polymorphism in Korean Ischemic Stroke Patients

Background and Purpose

We investigated the relationship between the β-fibrinogen gene (FGB) -455 G/A polymorphism and plasma fibrinogen levels in Korean ischemic stroke patients. We also determined whether the frequency of the -455 G/A polymorphism differed between two subtypes of noncardioembolic stroke: large-artery atherosclerosis (LAA) and small-vessel occlusion (SVO).

Methods

A total of 267 patients with noncardioembolic stroke were enrolled. Plasma fibrinogen and other risk factors for stroke were evaluated. FGB -455 G/A genotypes were determined by polymerase chain reaction with restrictive enzyme Hae III and automatic DNA sequencing.

Results

The FGB -455 G/A polymorphism was significantly associated with an elevated plasma fibrinogen level (p<0.001). The frequency of the A allele in Korean stroke patients was 16.7%. However, the frequency of the -455 G/A polymorphism did not differ between LAA and SVO.

Conclusions

The plasma fibrinogen level might be affected by the -455 G/A polymorphism in noncardioembolic stroke patients. However, the LAA and SVO subtypes of ischemic stroke were not affected by the -455 G/A polymorphism.     

High Levels of Remnant Lipoprotein Cholesterol Is a Risk Factor for Large Artery Atherosclerotic Stroke

Background and Purpose

Remnant lipoproteins (RLPs) are products of partially catabolized chylomicrons and very-low-density lipoprotein, from which some triglycerides have been removed. These particles are smaller and denser than the parent particles and are believed to be strongly atherogenic. We explored the association between RLP cholesterol (RLP-C) and ischemic stroke, including stroke subtypes.

Methods

A cohort of 142 ischemic stroke patients (90 men and 52 women; age, 65.2±12.8 years, mean±SD) was enrolled; all had acute infarcts confirmed by diffusion-weighted MRI, and had fasting lipograms. A full stroke-related evaluation was conducted on each patient. An outpatient population of 88 subjects without a history of cerebrovascular or cardiovascular disease served as a control group. Serum RLP fractions were isolated using an immunoaffinity gel containing specific antiapolipoprotein (anti-apo)B-100 and anti-apoA-I antibodies. RLP-C values were considered to be high when they were in the highest quartile of all values in the study.

Results

High RLP-C values were more common in stroke patients than in control patients (31.0% vs. 14.8%, p=0.01), when 5.6 mg/dL (>75th percentile) was used as the cutoff value. Multivariable analyses indicated that RLP-C was a risk factor for stroke, with an odds ratio of 2.54 (p=0.045). The RLP-C level was higher in the large artery atherosclerosis subgroup (5.7±3.9 mg/dL) than in any other stroke subgroup (small vessel occlusion, 4.9±5.9 mg/dL; cardioembolism, 1.8±2.3 mg/dL; stroke of undetermined etiology, 3.1±2.9 mg/dL).

Conclusions

We have found an association between high RLP-C levels and ischemic stroke, and in particular large artery atherosclerotic stroke.     

Antioxidant Effects of Statins in Patients with Atherosclerotic Cerebrovascular Disease

Background and Purpose

Oxidative stress is involved in the pathophysiological mechanisms of stroke (e.g., atherosclerosis) and brain injury after ischemic stroke. Statins, which inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, have both pleiotropic and low-density lipoprotein (LDL)-lowering properties. Recent trials have shown that high-dose statins reduce the risk of cerebrovascular events. However, there is a paucity of data regarding the changes in the oxidative stress markers in patients with atherosclerotic stroke after statin use. This study evaluated changes in oxidative stress markers after short-term use of a high-dose statin in patients with atherosclerotic stroke.

Methods

Rosuvastatin was administered at a dose of 20 mg/day to 99 patients who had suffered an atherosclerotic stroke and no prior statin use. Blood samples were collected before and 1 month after dosing, and the serum levels of four oxidative stress markers-malondialdehyde (MDA), oxidized LDL (oxLDL), protein carbonyl content (PCO), and 8-hydroxy-2''-deoxyguanosine (8-OHdG)-were evaluated to determine the oxidation of MDA and lipids, proteins, and DNA, respectively, at both of those time points.

Results

The baseline levels and the degrees of reduction after statin use differed among the oxidative stress markers measured. MDA and PCO levels were associated with infarct volumes on diffusion-weighted imaging (r=0.551, p<0.05, and r=0.444, p=0.05, respectively). Statin use decreased MDA and oxLDL levels (both p<0.05) but not the PCO or 8-OHdG level. While the reduction in MDA levels after statin use was not associated with changes in cholesterol, that in oxLDL levels was proportional to the reductions in cholesterol (r=0.479, p<0.01), LDL (r=0.459, p<0.01), and apolipoprotein B (r=0.444, p<0.05).

Conclusions

The impact of individual oxidative stress markers differs with time after ischemic stroke, suggesting that different oxidative markers reflect different aspects of oxidative stress. In addition, short-term use of a statin exerts antioxidant effects against lipid peroxidation via lipid-lowering-dependent and -independent mechanisms, but not against protein or DNA oxidation in atherosclerotic stroke patients.     

Non-cardioembolic Mechanisms in Cryptogenic Stroke: Clinical and Diffusion-weighted Imaging Features

Background

The role of several cardiogenic risk factors, including patent foramen ovale, in patients with cryptogenic stroke has been extensively studied. However, little attention has been paid to the role of non-cardioembolic causes of cryptogenic stroke. We therefore sought to identify the characteristics of cryptogenic stroke.

Methods

We studied 832 patients with acute infarction in the middle cerebral arterial territory. We divided the patients into four subtypes: 402 with large artery atherosclerosis (LAA), 133 with cardioembolism, 182 with small arterial occlusion (SAO), and 115 with cryptogenic stroke. We compared risk factors and lesion patterns observed by diffusion-weighted imaging (DWI) between patients with cryptogenic stroke and those with stroke of other subtypes.

Results

Both risk factors and DWI lesion patterns differed between the cryptogenic and cardioembolic groups (P<0.05). Risk factors for cryptogenic stroke were similar to those for the LAA and SAO groups. Similarly, DWI lesion patterns for cryptogenic stroke were similar to LAA patients. Large cortical infarcts on DWI were more common in the cardioembolic group than in the LAA or cryptogenic groups (P<0.001). In contrast, deep, non-lacunar (OR 5.02; 95% CI 2.68~9.40; P<0.001) and superficial perforator infarcts (OR 2.23; 95% CI 1.08~4.59; P=0.029) were independently associated with the cryptogenic group.

Conclusions

Our results indicate that non-cardioembolic causes, such as macro- and microangiopathy, are important mechanisms in the pathogenesis of cryptogenic stroke.     

Ischemic complications occurring in the contralateral hemisphere after surgical treatment of adults with moyamoya disease

Objective

Direct revascularization surgery is regarded as the most effective method of treatment of adults with moyamoya disease. These patients, however, have a higher risk of perioperative ischemic complications than do patients with atherosclerotic stroke, and are at risk for ischemic complications in the hemisphere contralateral to the one operated on. We investigated the incidence and risk factors for ischemic stroke in the contralateral hemisphere after surgical treatment of adults with moyamoya disease.

Methods

We retrospectively reviewed the medical records and results of neuroimaging studies on 79 hemispheres of 73 consecutive patients with adult moyamoya disease (mean±SD age, 37.96±11.27 years; range, 18-62 years) who underwent direct bypass surgery over 6 years.

Results

Ischemic complications occurred in 4 of 79 (5.1%) contralateral hemispheres, one with Suzuki stage 3 and three with Suzuki stage 4. Three patients showed posterior cerebral artery (PCA) involvement by moyamoya vessels. Advanced stage of moyamoya disease (Suzuki stages 4/5/6; p=0.001), PCA involvement (p=0.001) and postoperative hypotension (mean arterial blood pressure <80% of preoperative mean arterial blood pressure) on the first (p<0.0001) and second (p=0.003) days after surgery were significantly correlated with postoperative contralateral ischemic complications.

Conclusion

In patients with advanced moyamoya disease and involvement of the PCA, intentional hypotension can result in ischemic stroke in the hemisphere contralateral to the one operated on. Careful control of perioperative blood pressure is crucial for good surgical results.     

Non-conventional risk factors were associated with infarct patterns in ischemic stroke

Objective

Diffusion-weighted imaging (DWI) infarct patterns can play a useful role in the management of ischemic stroke patients, particularly in identifying index stroke mechanisms. Novel vascular risk factors like high sensitivity C-reactive protein (hs-CRP) and the metabolic syndrome have recently been shown to be of prognostic importance following ischemic stroke. We aimed to determine the relationship between these novel factors and infarct patterns noted on DWI.

Methods

A total of 886 patients with acute cerebral infarcts within the MCA territory were prospectively studied. Using the DWI data the patients were divided into four groups: cortical, small (<1 cm) superficial, border-zone, and deep infarcts patterns. The independent associations of various infarct DWI patterns vs. hs-CRP and presence of the metabolic syndrome were evaluated after adjusting for the confounders.

Results

hs-CRP was highest among patients with cortical infarcts, while the metabolic syndrome was most frequent in patients with border-zone infarcts. Compared to the lowest quartile of hs-CRP level, those in the highest quartile were more likely to have the cortical pattern (OR, 3.55; 95% CI, 1.92–6.56; P < 0.001), and less likely to have the deep infarct pattern (OR, 0.49; 95% CI, 0.29–0.81; P = 0.006) in logistic regression analyses. There was an independent association between presence of the metabolic syndrome and the border-zone pattern (OR, 1.75; 95% CI, 1.12–2.73; P = 0.013).

Conclusions

hs-CRP levels and metabolic derangements are independently associated with infarct pattern in acute ischemic stroke, and may be the potential targets for lessening the clinical impact of certain infarct patterns.     

Effect of 20 mg/day Atorvastatin: Recurrent Stroke Survey in Chinese Ischemic Stroke Patients with Prior Intracranial Hemorrhage

Background and Purpose

Treatment with atorvastatin (80 mg) in stroke secondary prevention for patients with prior intracranial hemorrhage (ICH) has been associated with a higher frequency of ICH. The aim of this study was to determine whether 20 mg/day atorvastatin is linked to stroke recurrence in Chinese ischemic stroke patients with prior ICH.

Methods

A single-center retrospective cohort study was conducted, involving 354 cases from 395 Chinese in-patients who had ischemic stroke with prior ICH history in Beijing Chaoyang hospital from May 1, 2005 to October 31, 2010. Survivors were followed by telephone interviews for 12-60 months. Cox regression and Kaplan-Meier plot analysis were used to evaluate the effect of 20 mg/day atorvastatin on cerebral infarction and ICH recurrence.

Results

The overall rate of stroke recurrence was lower in the 20 mg/day atorvastatin group (χ²=6.687, p=0.022) than in the control group. The incidence of cerebral hemorrhage was increased by 20 mg/day atorvastatin for ischemic stroke cases with a history of ICH compared to those not receiving the drug, but the difference was not significant [hazard ratio (HR)=1.097, 95% confidence interval (CI)=0.800-1.243, p=0.980]. The incidence of ischemic stroke recurrence was significantly reduced in subjects receiving atorvastatin (HR=0.723, 95% CI=0.578-0.862, p=0.028), and the mean duration of all stroke recurrences was significantly prolonged, compared with those not exposed to the drug (χ²=5.351, p=0.021). The mean duration of ICH recurrence appeared to have shortened with atorvastatin, but the difference was not significant (χ²=0.680, p=0.480), and the mean duration of cerebral infarction recurrence was significantly prolonged (χ²=8.312, p=0.004).

Conclusions

Medication with 20 mg/day atorvastatin may be beneficial in reducing ischemic stroke recurrence in ischemic stroke patients with a history of ICH and is not associated with an increased risk of ICH recurrence.     

Association between Ischemic Stroke and Vascular Shear Stress in the Carotid Artery

Background and Purpose

Vascular shear stress is essential for maintaining the morphology and function of endothelial cells. We hypothesized that shear stress in the internal carotid artery (ICA) may differ between patients with ischemic stroke and healthy control subjects.

Methods

ICA shear stress was calculated in 143 controls and 122 patients with ischemic stroke who had a normal ICA or an ICA with <50% stenosis. The stroke group included patients who presented with a first-ever or recurrent ischemic stroke but excluded cardioembolic stroke and uncertain etiologies. Of the 122 patients, 107 (87.7%) and 15 (12.3%) patients were categorized as first-ever and recurrent stroke, respectively.

Results

Carotid diameters were significantly larger, and both peak-systolic and end-diastolic velocities were significantly lower in patients with ischemic stroke than in controls (all p values <0.05). Mean values of peak-systolic and end-diastolic shear stress in both ICAs were significantly lower in patients with ischemic stroke in models that adjusted for age, sex, and vascular risk factors (p for trend <0.05). The ICA shear stress was lowest in patients with recurrent stroke or the subtype of small-vessel occlusion. Higher peak-systolic and end-diastolic shear stresses in both ICAs were independently and negatively associated with ischemic stroke after adjusting for potential confounders (all p values <0.05).

Conclusions

ICA shear stresses were significantly lower in patients with ischemic stroke than in control subjects. Future studies should attempt to define the causal relationship between carotid arterial shear stress and ischemic stroke.     

On the Severity of Carpal Tunnel Syndrome: Diabetes or Metabolic Syndrome

Background and Purpose

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Although its etiology is unknown, certain conditions are commonly associated with CTS, such as obesity, arthritis, hypothyroidism, diabetes mellitus, trauma, mass lesions, amyloidosis, and sarcoidosis. We aimed to determine the association between metabolic syndrome and CTS, and we compared the severity of CTS between patients with diabetes (and no concomitant metabolic syndrome) and patients with metabolic syndrome.

Methods

Two hundred patients with a clinically and electrophysiological confirmed diagnosis of CTS were included in the study. Their demographic characteristics and severity of CTS were analyzed according to the presence or the absence of metabolic syndrome. Differences in the electrophysiological findings were evaluated between the following four groups: 1) metabolic syndrome alone (n=52), 2) diabetes alone (n=20), 3) combined metabolic syndrome and diabetes (n=44), and 4) no metabolic syndrome or diabetes (n=84).

Results

CTS was more severe in the patients with metabolic syndrome than those without this syndrome. The electrophysiological findings were worse in patients with metabolic syndrome alone than in those with diabetes alone and those without diabetes and metabolic syndrome.

Conclusions

CTS appears to be more severe in patients with metabolic syndrome than patients with diabetes. Diabetes is one of the well-known risk factors for CTS, but other components of metabolic syndrome may have a greater effect on the severity of CTS.     

Urgent Recanalization with Stenting for Severe Intracranial Atherosclerosis after Transient Ischemic Attack or Minor Stroke

Objective

Stenting of symptomatic intracranial stenosis has recently become an alternative treatment modality. However, urgent intracranial stenting in patients with intracranial stenosis following a transient ischemic attack (TIA) or minor stroke is open to dispute. We sought to assess the feasibility, safety, and effectiveness of urgent intracranial stenting for severe stenosis (>70%) in TIA or minor stroke patients.

Methods

Between June 2009 and October 2010, stent-assisted angioplasty by using a balloon-expandable coronary stent for intracranial severe stenosis (>70%) was performed in 7 patients after TIA and 5 patients after minor stroke (14 stenotic lesions). Technical success rates, complications, angiographic findings, and clinical outcomes were retrospectively analyzed.

Results

Stenting was successful in all 12 patients. The mean time from symptom onset to stenting was 2.1 days (1-8 days). Post-procedural angiography showed restoration to a normal luminal diameter in all patients. In-stent thrombosis occurred in one patient (n=1, 8.3%), and was lysed with abciximab. No device-related complications, such as perforations or dissections at the target arteries or intracranial hemorrhaging, occurred in any patient. The mortality rate was 0%. No patient had an ischemic event over the mean follow-up period of 12.5 months (range, 7-21 months), and follow-up angiography (n=7) revealed no significant in-stent restenosis (>50%).

Conclusion

Urgent recanalization with stenting is feasible, safe, and effective in patients with TIA or acute minor stroke with intracranial stenosis of ≥70%.     

Ischemic Stroke in Takayasu's Arteritis: Lesion Patterns and Possible Mechanisms

Background and Purpose

The purpose of the present study was to use brain magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) to identify the mechanism of stroke in patients with Takayasu''s arteritis (TA).

Methods

Among a retrospective cohort of 190 TA patients, 21 (3 males and 18 females) with a mean age of 39.9 years (range 15-68 years) who had acute cerebral infarctions were included in lesion pattern analyses. The patients'' characteristics were reviewed, and infarction patterns and the degree of cerebral artery stenosis were evaluated. Ischemic lesions were categorized into five subgroups: cortical border-zone, internal border-zone, large lobar, large deep, and small subcortical infarctions.

Results

In total, 21 ischemic stroke events with relevant ischemic lesions on MRI were observed. The frequencies of the lesion types were as follows: large lobar (n=7, 33.3%), cortical border zone (n=6, 28.6%), internal border zone (n=1, 4.8%), small cortical (n=0, 0%), and large deep (n=7, 33.3%). MRA revealed that 11 patients had intracranial artery stenosis.

Conclusions

Hemodynamic compromise in large-artery stenosis and thromboembolic mechanisms play significant roles in ischemic stroke associated with TA.     

Cardiac Troponin T Elevation After Stroke: Relationships Between Elevated Serum Troponin T, Stroke Location, and Prognosis

Background and Purpose

Elevation of serum cardiac troponin T (cTnT) is regarded as a specific marker of acute coronary syndrome. Serum cTnT can be increased in patients with acute ischemic stroke, but its clinical implications remain unclear. The aim of this study was to identify the relationships between elevated cTnT and stroke severity, location, and prognosis.

Methods

From January 2005 to December 2006, this study recruited 455 consecutive patients who were admitted to Kangbuk Samsung Hospital due to acute ischemic stroke within 3 days of onset, which was confirmed by diffusion magnetic resonance imaging. A total of 416 patients was finally included and divided into 2 groups: an elevated cTnT group (n=45) and a normal cTnT group (n=371). The short-term prognosis was assessed by 30-day modified Rankin Scale responder analysis was compared between the two groups.

Results

Serum cTnT was elevated in 10.8% of cases, with elevated cTnT associated with greater stroke severity, as assessed by the National Institutes of Health Stroke Scale score, Insular-lobe involvement was more common in patients with elevated cTnT than in the normal cTnT group. Short-term prognosis was more unfavorable in the elevated cTnT group than in the normal cTnT group. Multivariate regression analysis indicated that elevated cTnT was independently related to insular involvement, cardioembolism, and unfavorable outcome.

Conclusions

Elevated cTnT in acute ischemic stroke was associated with severe neurological deficits at stroke onset and damages to the insular lobe. The outcome of acute ischemic stroke was worse for patients with elevated cTnT than for those with normal cTnT. The pathomechanism underlying acute ischemic stroke and subclinical myocardial damage warrants further study.     

Transesophageal Echocardiographic Findings Are Independent and Relevant Predictors of Ischemic Stroke in Patients with Nonvalvular Atrial Fibrillation

Background and Purpose

Not only clinical factors, including the CHADS₂ score, but also echocardiographic findings have been reported to be useful for predicting the risk of ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF). However, it remains to be determined which of these factors might be more relevant for evaluation of the risk of stroke in each patient.

Methods

In 490 patients with NVAF who underwent transesophageal echocardiography (TEE), we examined the long-term incidence of ischemic stroke events (mean follow-up time, 5.7±3.3 years). For each patient, the predictive values of gender, the CHADS₂ risk factors (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, history of cerebral ischemia), the CHADS₂ score, and the findings on echocardiography, including TEE risk markers, were assessed.

Results

The ischemic stroke rate was significantly correlated with the CHADS₂ score (p<0.05). According to the results of univariate analyses, age ≥75 years, history of cerebral ischemia, CHADS₂ score ≥2, and presence of TEE risk were significantly correlated with the incidence of ischemic stroke. Cox proportional hazards regression analyses identified age ≥75 years and presence of TEE risk as significant predictors of subsequent ischemic stroke events in patients with NVAF. As compared with that in persons below 75 years of age without TEE risk, the ischemic stroke rate was significantly higher in persons who were ≥75 years of age with TEE risk (4.3 vs. 0.56%/year, adjusted hazard ratio=8.94, p<0.001).

Conclusions

TEE findings might be more relevant predictors of ischemic stroke than the CHADS₂ score in patients with NVAF. The stroke risk was more than 8-fold higher in patients aged ≥75 years with TEE risk.     

Significance of Clopidogrel Resistance Related to the Stent-Assisted Angioplasty in Patients with Atherosclerotic Cerebrovascular Disease

Objective

To evaluate the prevalence and risk factors of clopidogrel resistance, and association between thromboembolic complications and clopidogrel resistance in patient with stent-assisted angioplasty for atherosclerotic cerebrovascular disease.

Methods

Between September 2006 and June 2008, clopidogrel resistance test was performed on 41 patients who underwent stent-assisted angioplasty for atherosclerotic cerebrovascular disease. It was performed before drug administration and about 12 hours after drug administration (loading dose : 300 mg, maintain dose : 75 mg). Two patients were excluded, and 41 patients were included (mean : 67.59±7.10 years, age range : 41-79). Among 41 patients, 18 patients had intracranial lesions, and 23 had extracranial lesions. We evaluated the prevalence, risk factors and complications related to clopidogrel resistance.

Results

Twenty-one patients (51.2%) showed clopidogrel resistance [intracranial : 10 patients (55.6%), extracranial : 11 patients (47.8%)] and no clopidogrel resistance was seen in 20 patients. Hypercholesterolemia was an indepedent risk factor of clopidogrel resistance. Stent-assisted angioplasty was technically successful in all patients, but acute in-stent thrombosis occurred in 5 patients with intracranial lesions (4 patients with clopidogrel resistance and 1 without clopidogrel resistance). Acute thrombi were completely lysed after intra-arterial infusion of abciximab.

Conclusion

There was relatively high prevalence of clopidogrel resistance in patients with atherosclerotic cerebrovascular disease. Hypercholesterolemia was an independent predictive factor of clopidogrel resistance. Acute in-stent thrombosis was more frequently seen in the clopidogrel resistant group. Therefore, clopidogrel resistance test should be performed to avoid thromboembolic complications related to stent-assisted angioplasty for atherosclerotic cerebrovascular disease, especially patients with hypercholeterolemia and intracranial lesion.     

Relation of glycated hemoglobin with carotid atherosclerosis in ischemic stroke patients: An observational study in Indian population

Context:

Glycated hemoglobin A₁c(HbA₁c) indicates long-term uncontrolled hyperglycemia in the body, which in diabetic patients leads to various vascular complications as a part of generalized atherosclerosis culminating ultimately into ischemic stroke.

Aims:

Study aims to show the association between marker of uncontrolled long-term hyperglycemia HbA₁c and marker of atherosclerosis (Carotid intima media thickness [CIMT] and carotid plaque) in ischemic stroke patients.

Subjects and Methods:

Carotid sonography using high resolution 7.5 MHz sonography technique was done in each patient to find the occurrence of increased CIMT and presence of plaque according to Mannheim CIMT Consensus (2004-2006). Levels of HbA₁c measured in blood in both diabetic and non-diabetic patients and a comparison made between them. Finally an association sought between HbA₁c levels with CIMT and plaque.

Results:

The average value of HbA₁c of this cohort was 7.51 ± 1.75% with higher values in diabetic patients (9.29 ± 1.73%). The patients with high CIMT (>0.8 mm) had higher values of HbA₁c then that of normal CIMT patients and this was nearly significantly (P = 0.06). However, HbA₁c levels of blood were significantly associated with stroke patients with presence of carotid arteries plaque (P = 0.008).

Conclusions:

Prediction of future risk and prevention strategies for ischemic stroke could be formulated by utilizing HbA₁c levels in both diabetic and non-diabetic population.     

Warfarin-Induced Intracerebral Hemorrhage Associated with Microbleeds

Background

Microbleeds (MBs), proposed as a biomarker for microangiopathy, have been suggested as a predictor of spontaneous or thrombolysis-related intracerebral hemorrhage (ICH) in acute ischemic stroke. However, the relationship between MBs and warfarin-induced ICH is not clear.

Case Report

We describe two patients who developed warfarin-induced ICH at the site of MBs documented in previous MRI.

Conclusions

The presence of MBs might increase the risk of ICH after warfarin use in ischemic stroke patients. A large cohort study is required to confirm the relationship of MBs with warfarin-induced ICH.     

Plaque Rupture is a Determinant of Vascular Events in Carotid Artery Atherosclerotic Disease: Involvement of Matrix Metalloproteinases 2 and 9

Background and Purpose

Unstable carotid atherosclerotic plaques are characterized by cap rupture, leading to thromboembolism and stroke. Matrix metalloproteinases (MMPs) have been implicated in the progression of atherosclerosis and plaque rupture. The aim of this study was to assess the relationship between the expressions of MMP-2 and MMP-9 and carotid plaque instability.

Methods

Eighty atherosclerotic plaques were collected from 74 patients undergoing carotid endarterectomy. Clinical information was obtained from each patient, and plaque morphology was examined at the macroscopic and microscopic levels. The immunohistochemical expressions of MMPs were graded using semiquantitative scales.

Results

Macroscopic ulceration (84.6% versus 63.4%, p=0.042) and microscopic cap rupture (79.5% versus 51.2%, p=0.010) were more common in symptomatic than in asymptomatic patients. Immunoreactivities of MMP-2 and MMP-9 were increased in 40 and 36 atheromatous plaques, respectively. Macroscopic ulceration was strongly correlated with the expressions of MMP-2 (p<0.001) and MMP-9 (p=0.001). There were significant correlations between increased MMP-2 expression and cap rupture (p=0.002), intraplaque hemorrhage (p=0.039), and a thin fibrous cap (p=0.002), and between increased MMP-9 expression and cap rupture (p=0.010) and a large lipid core (p=0.013).

Conclusions

Plaque rupture was significantly associated with the development of vascular events in carotid atherosclerotic disease. MMP-2 and MMP-9 are strongly correlated with plaque instability.     

Association between metabolic syndrome and previous ischemic lesions in patients with intracranial atherosclerotic stroke

Objectives

To elucidate the relationship between MetS and ischemic stroke, we evaluated the association of MetS and individual components with frequency of ischemic stroke lesions and investigated the independent associations between them in acute ischemic stroke patients.

Patients and methods

We evaluated 370 acute ischemic stroke patients who underwent brain magnetic resonance (MR) imaging and MR angiography. The stroke subgroups were categorized as intracranial large artery atherosclerosis (IC-LAA, n = 151), extracranial large artery atherosclerosis (EC-LAA, n = 35), and nonatherosclerosis (NA, n = 184). MetS was defined using the criteria of the International Diabetes Federation.

Results

Patients with IC-LAA group showed a higher rate of MetS and previous ischemic lesions (predominantly deep gray/white matter) than those with EC-LAA and NA (all P < 0.001). The number of previous ischemic lesions showed a tendency to increase as the number of MetS components increased in the IC-LAA group (P = 0.004). In the IC-LAA group, age (OR, 1.04) and MetS (OR, 3.28) were independently associated with previous ischemic lesions (all P < 0.001), which was prominent with more severe MetS components after adjustment for risk factors (P < 0.001). Among the component conditions, high blood pressure, impaired fasting glucose, and abdominal obesity were more associated with previous ischemic lesions (all P < 0.001) than low high-density lipoprotein and high triglyceride levels (P = 0.010 and 0.028, respectively).

Conclusion

Our study showed a strong association between MetS and previous ischemic lesions, more in patients with IC-LAA.     

Intravenous Recombinant Tissue Plasminogen Activator Thrombolysis in a Patient with Acute Ischemic Stroke Secondary to Aortic Dissection

Background

Acute ischemic stroke secondary to aortic dissection (AoD) is challenging in the era of thrombolysis owing to the diagnostic difficulty within a narrow time window and the high risk of complications.

Case Report

A 64-year-old woman with middle cerebral artery occlusion syndrome admitted to the emergency room within intravenous recombinant tissue plasminogen activator (rt-PA) time window. Her neurological symptoms improved during thrombolysis, but chest and abdominal pain developed. Repeated history-taking, physical examination, and imaging studies led to the timely diagnosis and surgical treatment of AoD, which produced a successful outcome.

Conclusions

Clinical suspicion is invaluable for the diagnosis of this rare cause of stroke. Considering the stroke mechanism and complications, the risks of thrombolysis might outweigh its benefits.