Intracranial atherosclerosis: incidence, diagnosis and treatment

Ischaemic stroke in a patient with non-valvular atrial fibrillation (NVAF) despite non-vitamin K oral anticoagulant (NOAC) therapy

Primary stroke prevention in non-valvular atrial fibrillation (NVAF) is primarily with non-vitamin K oral anticoagulant (NOAC) therapy. However, 20-36% of ischaemic strokes seem to occur in patients with atrial fibrillation while already on anticoagulation. We present a case of an ischaemic stroke in an elderly female in her 70s with medical history significant for hypertension and NVAF. She had a CHA2DS2-VASc score of 3 and was on apixaban for thromboprophylaxis. She presented with neurological deficits consistent with a left middle cerebral artery stroke, confirmed via head imaging; the most likely stroke aetiology was determined to be cardioembolic in the setting of NVAF. She was treated with continuation of her apixaban at the same dosage She displayed improved function, although with residual expressive aphasia at her 2-month neurology follow-up. Cardioembolic ischaemic stroke in NVAF despite current NOAC therapy does not have current management guidelines.

Glycoprotein inhibitors as a first line rescue treatment after unsuccessful recanalization of endovascular thrombectomy: A systematic review and meta-analysis

BACKGROUND

Intracranial atherosclerotic disease (ICAD) is a major cause of stroke with a high rate of re-occlusion following mechanical thrombectomy (MT). Among the available rescue options, glycoprotein IIb/IIIa inhibitors (GPI) have shown promise as a potential therapeutic strategy. This systematic review and meta-analysis examine studies exploring the use of glycoprotein inhibitors as a first-line treatment for refractory occlusion or high-grade stenosis following EVT in the setting of ICAD.

METHODS

A systematic review and meta-analysis were performed. Studies using GPI as the first-line rescue treatment (GPI-rt) after failed thrombectomy or in the setting with high-grade stenosis (>50%) were included. The primary outcome of interest was good clinical outcomes (defined as a modified Rankin Scale (mRS) score of 0-2 at 90 days). Secondary outcomes of interest were successful recanalization (TICI 2b-3), symptomatic intracranial hemorrhage (sICH), and mortality by 90 days.

RESULTS

Our study processed 2111 articles, which yielded eight relevant studies for review, four single and four double arm. These studies comprised 763 patients, divided into GPI-rt (535 patients) and non-GPI-rt (228 patients) cohorts. The GPI-rt group had higher rates of mRS ≤ 2 at 90 days (58.5% vs 38.9%, p = 0.002) and lower mortality rates (7.8% vs 17.5%, p = 0.04) compared to the non-GPI-rt cohort. mTICI 2b-3 rates and rates of sICH were not significantly different between the cohorts.

CONCLUSIONS

First line GPI-rt demonstrates significant clinical benefit and significantly lower mortality without a rise in rates of sICH. GPI are a potential first line rescue treatment of ICAD.

Effects of endovascular recanalization on symptomatic non-acute occlusion of intracranial arteries

To investigate the effect and safety of recanalization surgery for non-acute occlusion of large intracranial arteries and factors affecting clincial outcomes. Patients with non-acute occlusion of internal carotid artery (ICA), middle cerebral artery (MCA), and vertebrobasilar artery (VBA) treated with recanalization were retrospectively enrolled. The clinical and angiographic data were analyzed. 177 patients were enrolled, including 67 patients with intracranial ICA occlusion, 52 with MCA occlusion, and 58 with VBA occlusion. Successful recanalization was achieved in 152 (85.9%) patients. Complications occurred in 15 patients (8.5%). Followed up for 3-7 months, the 90 day mRS was significantly improved compared with that before the procedure. Among 152 patients with successful recanalization, eight patients experienced reocclusion (5.3%), and 11 patients experienced restenosis (7.2%). Successful recanalization was significantly (P < 0.05) associated with occlusion duration, calcification or angulation of the occluded segment. Complications were significantly (P < 0.05) associated with location of occlusion, hyperlipidemia, and patients' height. Restentosis or reocclusion at follow-up was significantly (P < 0.05) associated with complications and mRS at 90 days. The significant (P < 0.05) independent risk factors were angulation and calcification for successful recanalization, hyperlipidemia for complications, and mRS at 90 days for restenosis or reocclusion at follow-up. Recanalization surgery may be a safe and effective approach for patients with non-acute symptomatic occlusion of large intracranial arteries, and factors significantly independently associated with successful recanalization, periprocedural complications and restenosis or reocclusion after surgery have been identified for future reference to improve clinical outcomes.

Utility of high-resolution magnetic resonance vessel wall imaging in differentiating between atherosclerotic plaques, vasculitis, and arterial dissection

PURPOSE

Differentiating between atherosclerosis, vasculitis, and dissection is a diagnostic challenge because of inconclusive findings on conventional imaging and some overlap in the vessel wall patterns. The aim of this study was to determine whether vessel wall MRI patterns can differentiate between these vasculopathies.

METHODS

We retrospectively reviewed 3T high-resolution vessel wall imaging studies of patients diagnosed with atherosclerotic plaques, vasculitis, and dissection. The patterns of involvement, wall enhancement, and T1 and T2 signals, as well as the specific patterns, were assessed and compared between the three diseases.

RESULTS

Fifty-nine patients with atherosclerosis (n = 33), vasculitis (n = 13), and dissection (n = 13) were enrolled. There were significant differences in the pattern of involvement between the three groups (P < 0.001), with concentric wall thickening in vasculitis patients (84.6%) and eccentric wall thickening in atherosclerosis (97%) and dissection (92.3%) patients. There was also a significant difference in the specific pattern (P < 0.001), with intimal flap (76.9%) and intramural hematoma (23.1%) in dissection patients and intraplaque hemorrhage (18.2%) in atherosclerosis patients. Furthermore, subgroup analysis showed a significant difference in the wall enhancement pattern between atherosclerosis and vasculitis patients (P < 0.05). Finally, there was a significant difference in the location of involvement between the three groups (P < 0.001).

CONCLUSION

By using the pattern of involvement, wall enhancement, and specific patterns, vessel wall MRI can help differentiate between atherosclerosis, vasculitis, and dissection.

Association between serum calcium levels and first stroke: A community-based nested case-control study

Background

Evidence from epidemiologic studies has been limited and inconsistent regarding the role of serum calcium in stroke incidence risk. We aimed to evaluate the association between serum albumin-corrected calcium and the risk of the first stroke in the Chinese community-dwelling population.

Methods

The study sample population was drawn from the “H-type Hypertension and Stroke Prevention and Control Project.” Using a nested case-control study, a total of 1,255 first-stroke cases and 1,255 controls matched for age, sex, and village were included in the final data analysis. We measured the serum calcium by inductively coupled plasma mass spectrometry and assessed the associations between serum albumin-corrected calcium and first stroke using conditional logistic regression.

Results

The overall mean (SD) serum albumin-corrected calcium was 8.9 (0.6) mg/dl. Compared with the middle tertile (8.7–9.1 mg/dl), the multivariate-adjusted odds ratios (95% CIs) of first total stroke associated with the lowest tertile and the highest tertile of serum albumin-corrected calcium were 1.37 (1.10, 1.70) and 1.30 (1.04, 1.62), respectively. Similar trends were observed for the first ischemic stroke. Consistently, restricted cubic spline showed a U-shaped association between serum albumin-corrected calcium and risk of total stroke and ischemic stroke. However, serum albumin-corrected calcium had no significant effect on first hemorrhagic stroke. No significant effect modification was observed in the subgroup analysis.

Conclusions

Our results suggested a U-shaped association between serum calcium and first stroke; both low and high serum calcium levels were associated with an increased risk of the first stroke in the Chinese population.

Effect of traditional Chinese exercise on abnormal lipid metabolism in patients with atherosclerosis: a protocol for meta-analysis of randomised controlled trials

INTRODUCTION

Atherosclerosis (AS) is an abnormal response within the vessel wall to endothelial dysfunction and inflammatory cellular processes. Taijiquan exercise as a moderate-intensity aerobic exercise can control or reverse AS by gradually reducing the deposition of cholesterol on the walls of blood vessels. Similarly, performing Baduanjin exercise, Liuzijue Qigong, Wuqinxi exercise and Yijinjing exercise has been found to have a positive effect on lipid metabolism in patients with AS. However, these studies focused only on middle-aged and older populations over 50 years of age and had short intervention periods, poor quality control and patient compliance, and no stratification by age and gender to observe the effects of traditional Chinese exercise (TCE) on patients with AS. Therefore, this meta-analysis will explore the specific effects of different TCE interventions on lipid metabolism in patients with AS through subgroup analysis of factors such as age, gender, intervention cycle and training method and lay the foundation of evidence-based medicine for the promotion of TCE in both clinical practice and the community.

METHODS AND ANALYSIS

A systematic approach will be completed to search the literature published up to 30 September 2021 in the following databases: Web of Science, PubMed, Embase, Cochrane Library, EBSCO and CNKI. Other databases will also be searched manually. Lipid metabolism is the primary outcome indicator. Data synthesis, sensitivity analysis, regression analysis, subgroup analysis and risk bias evaluation will be performed using RevMan V.5.3 software. In addition, funnel plots generated by Begg's and Egger's tests will be used to assess reporting bias.

ETHICS AND DISSEMINATION

Ethical approval and consent are not necessary as no primary data will be collected. The results of the study will be disseminated through carefully reviewed publications.

PROSPERO REGISTRATION NUMBER

CRD42022304283.

4D flow MRI hemodynamic biomarkers for cerebrovascular diseases

Alterations in cerebral blood flow are common in several neurological diseases among the elderly including stroke, cerebral small vessel disease, vascular dementia, and Alzheimer's disease. 4D flow magnetic resonance imaging (MRI) is a relatively new technique to investigate cerebrovascular disease, and makes it possible to obtain time-resolved blood flow measurements of the entire cerebral arterial venous vasculature and can be used to derive a repertoire of hemodynamic biomarkers indicative of cerebrovascular health. The information that can be obtained from one single 4D flow MRI scan allows both the investigation of aberrant flow patterns at a focal location in the vasculature as well as estimations of brain-wide disturbances in blood flow. Such focal and global hemodynamic biomarkers show the potential of being sensitive to impending cerebrovascular disease and disease progression and can also become useful during planning and follow-up of interventions aiming to restore a normal cerebral circulation. Here, we describe 4D flow MRI approaches for analyzing the cerebral vasculature. We then survey key hemodynamic biomarkers that can be reliably assessed using the technique. Finally, we highlight cerebrovascular diseases where one or multiple hemodynamic biomarkers are of central interest.

Genetic Risk Factors of Intracranial Atherosclerosis

PURPOSE OF REVIEW

Intracranial atherosclerosis (ICAS) is the most common cause of stroke throughout the world. It also increases the risk of recurrent stroke and dementia. As a complex and multifactorial disease, ICAS is influenced by multiple genetic, biological, and environmental factors. This review summarizes the candidate gene and genome-wide studies aimed at discovering genetic risk factors of ICAS.

RECENT FINDINGS

Numerous studies have focused on the association between single-nucleotide polymorphisms (SNPs) of atherosclerosis-related genes and the risk of ICAS. Variants in adiponectin Q (ADIPOQ), ring finger protein 213 (RNF213), apolipoprotein E (APOE), phosphodiesterase 4D (PDE4D), methylenetetrahydrofolate reductase (MTHFR), lipoprotein lipase (LPL), α-adducin (ADD1) genes, angiotensin-converting enzyme (ACE), and other genes related to renin-angiotensin-aldosterone system have been associated with ICAS. We review the available evidences on the candidate genes and SNPs associated with genetic susceptibility to ICAS, and point out future developments of this field. Genetic discoveries could have clinical implications for intracranial atherosclerotic disease.

Intracranial Atherosclerosis and Stage 1 Hypertension Defined by the 2017 ACC/AHA Guideline

BACKGROUND

In 2017, the American College of Cardiology (ACC)/American Heart Association (AHA) released a new, stricter definition of stage 1 hypertension which was previously considered prehypertension. However, impacts of the novel stage 1 hypertension on deleterious target-organ outcomes are still controversial. In this study, we evaluated the relationship between this newly defined stage 1 hypertension and the presence of intracranial atherosclerosis (ICAS) lesions in neurologically healthy participants.

METHODS

We assessed consecutive participants in routine health checkups between January 2006 and December 2013. Blood pressure (BP) was classified according to the 2017 ACC/AHA hypertension guideline, and ICAS was defined as occlusion or ≥50% stenosis of intracranial vessels on flight magnetic resonance angiography.

RESULTS

Among 3,111 healthy participants (mean age: 56 years, sex: 54% men), 85 (3%) had ICAS lesions. In multivariate analysis, stage 1 hypertension (adjusted odds ratio: 2.46, 95% confidence interval: 1.10-5.51, P = 0.029) remained an independent predictor of ICAS after adjustment for confounders. Stage 2 hypertension showed a higher odds ratio and a lower P value, indicating a dose-response effect. Age and HbA1c level were also significantly associated with ICAS, independent of the BP categories. The ICAS lesion burden showed a dose-response effect across the BP categories (P for trend <0.001), whereas ICAS lesion location did not (P for trend = 0.699).

CONCLUSIONS

We demonstrated that stage 1 hypertension, defined according to the 2017 ACC/AHA guideline, was associated with a higher prevalence and burden of ICAS lesions in a neurologically healthy population.

Neutrophil-to-lymphocyte ratio predicts early worsening in stroke due to large vessel disease

Background

Inflammation plays an important role in atherosclerosis and its complications. Since a dysregulated inflammatory response is associated with early neurological deterioration (END), serum neutrophil-to-lymphocyte ratio (NLR) could be a marker of END as well.

Aim

In this study, we evaluated the relationship between the serum NLR and END in patients with ischemic stroke due to large-artery atherosclerosis (LAA).

Methods

We evaluated consecutive patients with ischemic stroke due to LAA between January 2010 and December 2015. END was defined as an increase ≥ 2 on the total NIHSS score or ≥ 1 on the motor NIHSS score within the first 72 hours of admission. The NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count.

Results

Of the 349 included patients, 18.1% (n = 63) had END events. In multivariate analysis, serum NLR was independently associated with END (adjusted odds ratio, 1.08; 95% confidence interval [1.00–1.16], P = 0.043). Time to admission, and in-situ thrombosis and artery-to-artery embolization mechanisms were also significantly associated with END events. In an analysis of the relationship between serum NLR and vascular lesion burden, serum NLR was positively correlated with both the degree of stenotic lesions (P for trend = 0.006) and the number of vessel stenosis (P for trend = 0.038) in a dose-response manner. We also compared serum NLR by the stroke mechanisms: patients with hypoperfusion or in-situ thrombosis had the highest levels of NLR: however, only those with in-situ thrombosis had significantly higher NLR in the END group compared to the non-END group (P = 0.005).

Conclusions

Serum NLR levels were associated with END events in patients with ischemic stroke due to LAA. Since NLR was also closely correlated with the underlying vascular lesions, our results indicated clues for mechanisms of END events.

Clopidogrel plus Aspirin for Symptomatic Intracranial Atherosclerotic Stenosis: A Pilot Study

BACKGROUND AND PURPOSE

There are limited data on the optimal duration of dual antiplatelet therapy for secondary stroke prevention in patients with symptomatic intracranial atherosclerotic disease.

METHODS

Consecutive patients presenting with high-grade (70-99%) symptomatic intracranial stenosis from January 1, 2011, to December 31, 2013, and evaluated within 30 days of the index event were eligible for this analysis. All patients underwent treatment with aspirin plus clopidogrel for a target duration of 12 months along with aggressive medical management based on the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) protocol; all patients were given gastrointestinal prophylaxis for the duration of their aspirin and clopidogrel treatment. Clinical and safety outcomes of our cohort were compared with the medical arm of the SAMMPRIS trial cohort (n = 227).

RESULTS

Our cohort included 25 patients that met the inclusion criteria. Achievement of blood pressure and LDL cholesterol targets were similar between our cohort and the SAMMPRIS cohort. At 1 year, the rates of stroke, myocardial infarction or vascular death were 0% in our cohort and 16% in the SAMMPRIS cohort (p = 0.03). At 1 year, major bleeding rates were similar between our cohort and the SAMMPRIS cohort (4 vs. 2.2%, p = 1.0).

CONCLUSION

A prolonged course of dual antiplatelet therapy for symptomatic intracranial atherosclerotic disease may be associated with less vascular events with no increase in hemorrhagic complications.

A non-invasive technique for visualization of microvessels in asymptomatic patients with middle cerebral artery steno-occlusion

We determined whether 7T magnetic resonance angiography (MRA) could be used for clearly observing microvessels in a clinically asymptomatic patient with steno-occlusion of the middle cerebral artery (MCA). We utilized 3T magnetic resonance imaging to obtain the brain images of a clinically asymptomatic patient and noted MCA steno-occlusion. In comparison with 3T MRA, 7T MRA could clearly delineate the microvessels, including lenticulostriate arteries and presumed collaterals, and our observation was comparable to that with conventional digital subtraction angiography. We report an interesting case of a clinically asymptomatic patient with MCA steno-occlusion.

Low HDL-C level is associated with the development of intracranial artery stenosis: analysis from the Chinese IntraCranial AtheroSclerosis (CICAS) study

BACKGROUND

Intracranial atherosclerotic stenosis (ICAS) is an important cause of ischemic stroke worldwide. The role of high-density lipoprotein cholesterol (HDL-C) or low-density lipoprotein cholesterol (LDL-C) in the development of ICAS remains to be elucidated. In the current study, we investigated the relationship of HDL-C level and the risk of developing ICAS in Chinese patients with acute ischemic stroke.

METHODS

From October 2007 to June 2009, a total of 1,984 consecutive ischemic stroke patients were evaluated for the presence of symptomatic ICAS by magnetic resonance angiography (MRA). Patients were classified into two groups: intracranial steno-occlusion (ICAS group, n = 888) and non-intracranial stenosis (NICAS group, n = 1096). Serum lipid profiles were analyzed and compared between the ICAS and NICAS group.

RESULTS

Significantly more patients in ICAS group had low HDL-C level (51.6%) than in the NICAS group (42.9%, P<0.001). The observed association remained significant after adjustment for conventional risk factors [(adjusted OR 1.36; 95%CI (1.13-1.63)]. Such predictive value of low level HDL-C persisted even when LDL-C was at very low level(<1.8 mmol/L). Patients in the lowest serum HDL-C quartile (<0.96 mmol/L) had the highest risk of developing ICAS [adjusted OR 1.52; 95%CI (1.17-1.98)] compared to patients in the highest serum HDL-C quartile (≥ 1.32 mmol/L) after adjustments for the covariates.

CONCLUSIONS

Low HDL-C level is strongly associated with the development of ICAS. There was an inverse relationship between the level of HDL-C and the risk of developing ICAS.

Correlation between high-sensitivity C-reactive protein and brain gray matter volume in healthy elderly subjects

Although elevated serum high-sensitivity C-reactive protein (hsCRP) is related to atherosclerosis, brain infarction, and cognitive decline, it has not been clarified whether increased hsCRP is associated with the decline in brain gray matter volume. Therefore, the purpose of this study was to determine the relationship between hsCRP levels and brain regional gray matter volume using brain magnetic resonance imaging (MRI) data from 109 community-dwelling healthy elderly subjects. Brain MRIs were processed with voxel-based morphometry using a custom template by applying diffeomorphic anatomical registration using the exponentiated lie algebra (DARTEL) procedure. We found a significant negative correlation between regional gray matter volume of the posterior and lateral aspects of the left temporal cortex and hsCRP level after adjusting for age, gender, and intracranial volume. Our results suggest that subjects who have mild inflammation related to arteriosclerosis have decreased regional gray matter volume in the posterior and lateral aspects of the left temporal cortex. Thus, preventing the progression of arteriosclerosis may be important for preventing a decrease in gray matter volume in healthy elderly subjects.

An unexpected evolution of symptomatic mild middle cerebral artery (MCA) stenosis: asymptomatic occlusion

BACKGROUND

The intracranial localization of large artery disease is recognized as the main cause of ischemic stroke in the world, considering all countries, although its global burden is widely underestimated. Indeed it has been reported more frequently in Asians and African-American people, but the finding of intracranial stenosis as a cause of ischemic stroke is relatively common also in Caucasians. The prognosis of patients with stroke due to intracranial steno-occlusion is strictly dependent on the time of recanalization. Moreover, the course of the vessel involvement is highly dynamic in both directions, improvement or worsening, although several data are derived from the atherosclerotic subtype, compared to other causes.

CASE DESCRIPTION

We report the clinical, neurosonological and neuroradiological findings of a young woman, who came to our Stroke Unit because of the abrupt onset of aphasia during her work. An urgent neurosonological examination showed a left M1 MCA stenosis, congruent with the presenting symptoms; magnetic resonance imaging confirmed this finding and identified an acute ischemic lesion on the left MCA territory. The past history of the patient was significant only for a hyperinsulinemic condition, treated with metformine, and a mild overweight. At this time a selective cerebral angiography was not performed because of the patient refusal and she was discharged on antiplatelet and lipid-lowering therapy, having failed to identify autoimmune or inflammatory diseases. Within 1 month, she went back to our attention because of the recurrence of aphasia, lasting about ten minutes. Neuroimaging findings were unchanged, but the patient accepted to undergo a selective cerebral angiography, which showed a mild left distal M1 MCA stenosis.During the follow-up the patient did not experienced any recurrence, but a routine neurosonological examination found an unexpected evolution of the known MCA stenosis, i.e. left M1 MCA occlusion. Neuroradiological imaging did not identify new lesions of the brain parenchyma and a repeated selective cerebral angiography confirmed the left M1 MCA occlusion.

CONCLUSIONS

Regardless of the role of metabolic and/or inflammatory factors on the aetiology of the intracranial stenosis in this case, the course of the vessel disease was unexpected and previously unreported in the literature at our knowledge.

Amlodipine besylate and amlodipine camsylate prevent cortical neuronal cell death induced by oxidative stress

We examined the neuroprotective effects of the long-acting third-generation dihydropyridine Ca(2+) antagonists, amlodipine besylate (AB) and amlodipine camsylate (AC), on neuronal cell death induced by oxidative stress. Cell viability and levels of free radicals and intracellular signaling proteins were measured after treating primary cultures of cortical neurons with AB, AC, and/or hydrogen peroxide (H(2) O(2) ) under various conditions. Cell viability was not affected by concentrations of AB or AC up to 5 μM but decreased at higher concentrations. Following H(2) O(2) exposure, the viability of cortical neurons decreased in a concentration-dependent manner; however, treatment with AB or AC up to 5 μM restored the viability of H(2) O(2) -injured cortical neurons. Treatment with H(2) O(2) increased the level of free radicals in cortical neurons, and pre-treatment with AB or AC counteracted this in a dose-dependent manner. Similarly, treatment with AB or AC reduced the declines in p85aPI3K, phosphorylated Akt, phosphorylated GSK-3β, heat-shock transcription factor-1, and Bcl-2 induced by H(2) O(2) , as well as the increases in cyclooxygenase-2, cytosolic cytochrome c, cleaved caspase 9, and cleaved caspase 3. Our results indicate that AB and AC exert similar neuroprotective effects by reducing oxidative stress, enhancing survival signals, and inhibiting death signals.

Stenting versus aggressive medical therapy for intracranial arterial stenosis

BACKGROUND

Atherosclerotic intracranial arterial stenosis is an important cause of stroke that is increasingly being treated with percutaneous transluminal angioplasty and stenting (PTAS) to prevent recurrent stroke. However, PTAS has not been compared with medical management in a randomized trial.

METHODS

We randomly assigned patients who had a recent transient ischemic attack or stroke attributed to stenosis of 70 to 99% of the diameter of a major intracranial artery to aggressive medical management alone or aggressive medical management plus PTAS with the use of the Wingspan stent system. The primary end point was stroke or death within 30 days after enrollment or after a revascularization procedure for the qualifying lesion during the follow-up period or stroke in the territory of the qualifying artery beyond 30 days.

RESULTS

Enrollment was stopped after 451 patients underwent randomization, because the 30-day rate of stroke or death was 14.7% in the PTAS group (nonfatal stroke, 12.5%; fatal stroke, 2.2%) and 5.8% in the medical-management group (nonfatal stroke, 5.3%; non-stroke-related death, 0.4%) (P=0.002). Beyond 30 days, stroke in the same territory occurred in 13 patients in each group. Currently, the mean duration of follow-up, which is ongoing, is 11.9 months. The probability of the occurrence of a primary end-point event over time differed significantly between the two treatment groups (P=0.009), with 1-year rates of the primary end point of 20.0% in the PTAS group and 12.2% in the medical-management group.

CONCLUSIONS

In patients with intracranial arterial stenosis, aggressive medical management was superior to PTAS with the use of the Wingspan stent system, both because the risk of early stroke after PTAS was high and because the risk of stroke with aggressive medical therapy alone was lower than expected. (Funded by the National Institute of Neurological Disorders and Stroke and others; SAMMPRIS ClinicalTrials.gov number, NCT00576693.).

Subtyping of ischemic stroke based on vascular imaging: analysis of 1,167 acute, consecutive patients

Background and Purpose

Knowledge of a patient's cerebral vascular status is essential for accurately classifying stroke. However, vascular evaluations have been incomplete in previous studies, and a stroke registry based on the results of such vascular investigations has not been reported. The purpose of the present study was to classify ischemic strokes based on vascular imaging data.

Methods

Between May 2001 and August 2003, 1,264 patients with acute (< 7 days) ischemic stroke were admitted to Asan Medical Center. Among them, 1,167 patients (750 men and 417 women; mean age 63.3 years) underwent an angiogram (mostly a magnetic resonance angiogram) and were included in this study. Electrocardiography and computed tomography/magnetic resonance imaging were performed in all patients, while 31.2% underwent echocardiography. The subtypes were categorized with the aid of a modification of the Trial of ORG 10172 in the Acute Stroke Treatment classification.

Results

Large-artery atherosclerosis (LAA) was the most frequent subtype (42%), followed by small-vessel occlusion (SVO, 27%), cardiogenic embolism (CE, 15%), undetermined etiology (15%), and other determined etiology (1.5%). Risk factors included hypertension (71%), cigarette smoking (35%), diabetes mellitus (30%), history of previous stroke (22.7%), emboligenic cardiac diseases (20%), and hypercholesterolemia (11%). Hypertension was more common in patients with SVO than in those with other subtypes (p<0.05), and the case-fatality rate was higher in patients with CE than in those with other subtypes (p<0.01). The functional outcome was worse in patients with LAA than in those with other stroke subtypes (p<0.01).

Conclusion

According to the stroke registry based on vascular imaging results, LAA was the most common stroke subtype followed by SVD. The high incidence of LAA is probably related to the increased identification of the presence of intracranial atherosclerosis by MR angiogram.

Is 15 mm size criterion for lacunar infarction still valid? A study on strictly subcortical middle cerebral artery territory infarction using diffusion-weighted MRI

BACKGROUND AND PURPOSE

The 'lacunar hypothesis' has been challenged, since small (diameter <15 mm) subcortical infarcts can be produced by middle cerebral artery disease (MCAD) or cardioembolism (CE), while a larger infarct can occur without evidence of MCAD or CE. We sought to assess whether the lacunar hypothesis based on size is still valid.

METHODS

We studied 118 patients who were admitted within 72 h after stroke onset and had acute deep subcortical MCA territory infarcts detected by diffusion-weighted MRI, and who had undergone angiography (mostly MR angiography). Stroke mechanisms were arbitrarily categorized regardless of lesion size: (1) MCAD when there was a corresponding MCA lesion; (2) internal carotid artery disease (ICAD) when there was a significant (>50%) ipsilateral ICAD; (3) CE when there was emboligenic heart disease without MCAD or ICAD, and (4) small vessel disease (SVD) when there was neither CE nor MCAD. SVD was further divided into definite SVD (dSVD, longest diameter <15 mm) or probable SVD (pSVD, longest diameter > or =15 mm).

RESULTS

Seventy-three patients (62%) had SVD, of which 38 (32%) had pSVD and 35 (30%) dSVD. Thirty-three patients (28%) had MCAD, five (4%) CE, and seven (6%) ICAD. The infarct diameter in MCAD was not larger than in SVD (p = 0.35), and there was no difference in clinical features or risk factors between MCAD and SVD, or between pSVD and dSVD. CE was distinguished from SVD by its larger size and cortical symptoms.

CONCLUSIONS

There are no clinical and lesion-size differences between MCAD and SVD, suggesting that there seems to be no rationale for the 15 mm size criterion for lacunar or small-vessel infarction.