Symptomatic Intracranial Atherosclerosis Research Articles

P-022 Treating symptomatic intracranial atherosclerosis with the balloon expandable Pharos Vitesse neurovascular stent: initial experience

PurposeTo describe our early experience with the balloon expandable Pharos Vitesse stent for symptomatic, high grade intracranial stenosis.Materials and methodsOur center has enrolled five patients to date in the VISSIT...

Predictive Factors for In-stent Restenosis after Balloon-mounted Stent Placement for Symptomatic Intracranial Atherosclerosis

Objectives We sought to evaluate whether clinical, lesion-related and procedural factors may predict in-stent restenosis (ISR) after intracranial stenting. Methods Sixty-one Chinese patients with 65 lesions treated with single bare metal balloon-mounted stent for symptomatic intracranial arterial stenosis underwent conventional angiographic follow-up after procedures between March 2004 and July 2009. Clinical, lesion-related and procedural factors were analysed for any predictive power for the ISR using univariate and multivariate analysis. ISR was defined as >50% stenosis within or at the edge of the stent or absolute luminal loss >20%. Results ISR was found in 18 patients (18/61, 29.5%) with 20 lesions (20/65, 30.8%) at a median follow-up of 7 months (range, 5–30 months). Univariate analysis revealed that diabetes, Mori classification, lesion length and stent diameter were associated with ISR. In addition, diabetes (hazard ratio (HR), 2.661; 95% confidence interval (CI), 1.044–6.787; P = 0.040) and lesion length (HR, 1.206; 95% CI, 1.023–1.421; P = 0.026) were detected as two independent predictors for ISR by stepwise multivariate Cox regression analysis. Conclusions ISR after intracranial stenting with bare metal balloon-mounted stents in our series seems to be more frequent than those reported by the majority of the published case series. Diabetes and lesion length are associated with increased risk of ISR.

Periprocedural MRI perfusion imaging to assess and monitor the hemodynamic impact of intracranial angioplasty and stenting for symptomatic atherosclerotic stenosis

We aimed to assess the clinical value of MRI perfusion imaging in the periprocedural management of intracranial atherosclerosis, analyzing if changes in mean transit time (MTT), cerebral blood volume (CBV) and cerebral blood flow (CBF) correlated with angiographic outcomes. Pre-procedural and post-procedural MRI perfusion was performed on six patients who underwent angioplasty and/or stenting for symptomatic intracranial atherosclerosis. MTT, CBV and CBF were analyzed and graded. In 83% of patients, perfusion imaging correlated with angiographic outcomes. Perfusion parameters improved to normal in two patients. Two showed marked improvement and one showed mild improvement. In one patient, the results of the post-procedural MRI perfusion prompted an angiogram, which confirmed stent occlusion. Semi-quantitative scores of MTT and CBF changed over time ( p = 0.05, p = 0.03) whereas CBV did not change significantly ( p > 0.05). We conclude that MRI perfusion appears a promising technique for analyzing the impact of intracranial stenosis on cerebral hemodynamics before and after treatment.

COMPARISON BETWEEN PRIMARY ANGIOPLASTY AND STENT PLACEMENT FOR SYMPTOMATIC INTRACRANIAL ATHEROSCLEROTIC DISEASE

To compare the short- and long-term rates of stroke-and/or-death associated with primary angioplasty alone and angioplasty with stent placement using a meta-analysis of published studies. Both primary angioplasty alone and angioplasty with stent placement have been proposed as treatment strategies for symptomatic intracranial atherosclerotic disease to reduce the risk of stroke-and/or-death with best medical treatment alone. However, it remains unclear which of these endovascular techniques offers the best risk reduction. We identified pertinent studies published between January 1980 and May 2008 using a search on PubMed and Cochrane libraries, supplemented by a review of bibliographies of selected publications. The incidences of stroke-and/or-death were estimated for each report and pooled for both angioplasty alone and angioplasty with stent placement at 1 month and 1 year postintervention and then compared using a random-effects model. The association of year of publication and 1-year incidence of stroke-and/or-death was analyzed with meta-regression. After applying our selection criteria, we included 69 studies (33 primary angioplasty-alone studies [1027 patients] and 36 studies of angioplasty with stent placement [1291 patients]) in the analysis. There were a total of 91 stroke-and/or-deaths reported in the angioplasty-alone-treated group (8.9%; 95% confidence interval [CI], 7.1%-10.6%), compared with 104 stroke-and/or-deaths in the angioplasty-with-stent-treated group (8.1%; 95% CI, 6.6%-9.5%) during a 1-month period (relative risk [RR], 1.1; P = 0.48). The pooled incidence of 1-year stroke-and/or-death in patients treated with angioplasty alone was 19.7% (95% CI, 16.6%-23.5%), compared with 14.2% (95% CI, 11.9%-16.9%) in the angioplasty-with-stent-treated patients (RR, 1.39; P = 0.009). The incidence of technical success was 79.8% (95% CI, 74.7%-84.8%) in the angioplasty-alone group and 95% (95% CI, 93.4%-96.6%) in the angioplasty-with-stent-treated group (RR, 0.84; P < 0.0001). The pooled restenosis rate was 14.2% (95% CI, 11.8-16.6%) in the angioplasty-alone group, as compared with 11.1% (95% CI, 9.2%-13.0%) in the angioplasty-with-stent-treated group (RR, 1.28; P = 0.04). There was no effect of the publication year of the studies on the risk of stroke-and/or-death. Risk of 1-year stroke-and/or-death and rate of angiographic restenosis may be lower in symptomatic intracranial atherosclerosis patients treated by angioplasty with stent placement compared with patients treated by angioplasty alone.

Treatment of atherosclerotic intracranial arterial stenosis.

David Pelz MD L. Nelson Hopkins MD Elad Levy MD Section Editors: Atherosclerotic stenosis of the major intracranial arteries (intracranial internal carotid artery, middle cerebral artery, vertebral artery, basilar artery) is probably the most common cause of stroke worldwide.1 Intracranial atherosclerosis causes 30% to 50% of strokes in Asia2 and 8% to 10% of strokes in North America.3 This review focuses on the medical and endovascular treatment of atherosclerotic intracranial arterial stenosis. Initially, a retrospective study suggested that warfarin was superior to aspirin for stroke prevention in patients with symptomatic intracranial arterial stenosis.4 This retrospective data combined with a proposed pathophysiological rationale for anticoagulation5 made warfarin a common treatment choice for symptomatic intracranial stenosis.6 However, the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial showed that aspirin was safer and as effective as warfarin for stroke prevention in patients with symptomatic intracranial stenosis. WASID was stopped early after a mean follow-up of 1.8 years because of higher rates of death and major hemorrhage in the warfarin arm. The primary end point of ischemic stroke, brain hemorrhage or vascular death, occurred in 22.1% of patients assigned aspirin and 21.8% of those in the warfarin group.7 The rates of myocardial infarction or sudden death were also higher in the warfarin arm. Certain high-risk subgroups of patients with intracranial stenosis were previously thought to benefit from anticoagulation, such as those with severe stenosis,4 vertebrobasilar disease,4 and those who have failed antithrombotic therapy.8 In WASID, however, patients with severe stenosis9 or those previously on antithrombotic therapy9,10 did not benefit from warfarin. Patients with basilar artery stenosis in WASID did appear to have a lower rate of the primary end point on warfarin, but there was no difference in the rate of stroke in the …

TREATMENT OF SYMPTOMATIC MIDDLE CEREBRAL ARTERY STENOSIS WITH BALLOON-MOUNTED STENTS

Primary stenting is a well-established treatment for coronary artery disease and has been applied to symptomatic intracranial stenosis in selected patients. This study reports a large case series of middle cerebral artery revascularization using balloon-mounted coronary stents. The series consisted of 113 consecutive patients with symptomatic middle cerebral artery stenosis and more than 70% occlusion who underwent intracranial stenting at a single center from 2001 to 2006. Technical success, periprocedural complications, recurrent symptoms, and restenosis were retrospectively reviewed. Risk factors for restenosis were analyzed using logistic regression and the chi(2) test. The mean age of the patients was 48 +/- 11 years (range, 25-79 years). Seventy-three patients presented with transient ischemic attacks, and 40 patients were diagnosed with acute stroke. The technical success rate was 96.46%. The mean stenosis was reduced from 80.83 +/- 8.77% to 3.71 +/- 8.15%. The rate of stroke and death within 30 days was 4.42%. Eighty-nine patients were followed for an average period of 29 +/- 16 months (range, 9 months-5 years). Seventy-nine vessels were followed with transcranial Doppler and 36 vessels with angiography or computed tomographic angiography. Recurrent stroke or transient ischemic attacks occurred in 6 patients (6.74%). The restenosis rate was 20.25%. Restenosis was associated with diabetes and hyperlipidemia but not with age, sex, hypertension, or drug-eluting stent. Primary stenting of symptomatic middle cerebral artery stenosis can be performed with high success and low complication rates. Randomized clinical studies are warranted to compare the safety and efficacy of various endovascular revascularization techniques with maximal medical therapy in patients with symptomatic intracranial atherosclerosis.

Comparison of Primary Angioplasty With Stent Placement for Treating Symptomatic Intracranial Atherosclerotic Diseases

We sought to compare the clinical outcomes between primary angioplasty and stent placement for symptomatic intracranial atherosclerosis. We retrospectively analyzed the clinical and angiographic data of 190 patients treated with 95 primary angioplasty procedures and 98 intracranial stent placements (total of 193 procedures) in 3 tertiary care centers. Stroke and combined stroke and/or death were identified as primary clinical end points during the periprocedural and follow-up period of 5 years. The rates of significant postoperative residual stenosis (>/=50% of greater stenosis immediately after the procedure) and binary restenosis (>/=50% stenosis at follow-up angiography within 3 years) were also compared. The comparative analysis was performed after adjusting for age, sex, and center. Fourteen procedures in the angioplasty-treated group (15%) and 4 in the stent-treated group (4.1%) had significant postoperative residual stenosis (relative risk [RR]=2.8, 95% CI, 0.85 to 9.5, P=0.09, for the adjusted model). There were 3 periprocedural deaths (1.5%), 1 in the angioplasty group (1.1%) and 2 in the stent-treated group (2.0%) and 14 periprocedural strokes (7.3%), 7 periprocedural strokes in each group (7.4% and 7.1%, respectively; hazard ratio=1.1; 95% CI, 0.57 to 1.9, P=0.85). Angiographic follow-up was available for 134 procedures (66 angioplasty-treated and 68 stent-treated cases). Forty-eight procedures (36.1%) had evidence of binary restenosis (25 of 66 angioplasties, 23 of 68 stents, P=0.85). Binary restenosis-free survival at 12 months was 68% for the angioplasty-treated group and 64% for the stent-treated group. There was no difference in follow-up survival (stroke, or stroke and/or death) between the angioplasty-treated and the stent-treated groups (hazard ratio=0.54; 95% CI, 0.11 to 2.5, P=0.44 and hazard ratio=0.50; 95%, CI 0.17 to 1.5, P=0.22, respectively, after adjusting for age, sex, and center). The stroke- and/or death-free survival at 2 years for the angioplasty-treated group and the stent-treated group was 92+/-4% and 89+/-5%, respectively. Stent treatment for intracranial atherosclerosis may lower the rate of significant postoperative residual stenosis compared with primary angioplasty alone. No benefit of stent placement over primary angioplasty in reducing stroke or stroke and/or death could be identified in this study.

CURRENT CONCEPTS IN THE MANAGEMENT OF INTRACRANIAL ATHEROSCLEROTIC DISEASE

Medically refractory, symptomatic intracranial atherosclerotic disease has a poor prognosis. Based on the results of the Warfarin-Aspirin Symptomatic Intracranial Disease study, the risk of ipsilateral stroke at 1.8 years is between 13 and 14% in patients with symptomatic intracranial atherosclerosis. Synergistic advances in intracranial angioplasty and stenting, modern neuroimaging techniques, and periprocedural and postprocedural antithrombotic regimens are creating new models for the diagnosis and successful endovascular treatment of intracranial stenosis. In this article, the most recent clinical developments and concepts for the diagnosis and endovascular treatment of intracranial atherosclerotic disease are discussed.

Progression of Symptomatic Intracranial Large Artery Atherosclerosis Is Associated With a Proinflammatory State and Impaired Fibrinolysis

The molecular pathways involved in the progression of intracranial large artery atherosclerosis (ILA) are largely unknown. Our objective was to prospectively study the relationship between circulating levels of inflammatory markers and fibrinolysis inhibitors, and the risk of progression of symptomatic ILA. Seventy-five consecutive patients with first-ever symptomatic intracranial atherostenosis were studied. Blood levels of C-reactive protein (CRP), E-selectin, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, matrix metalloproteinases 1, 2, 3, 8, 9, 10, and 13, plasminogen activator inhibitor-1 (PAI-1), and lipoprotein(a) were measured 3 months after the qualifying stroke or transient ischemic attack. Thereafter, patients underwent long-term transcranial Doppler follow-up to detect progression of ILA. During a median follow-up time of 23 months, 25 (33%) patients showed ILA progression. Multivariable adjusted Cox regression models and Kaplan-Meier curves showed that high baseline level of CRP, E-selectin, intercellular adhesion molecule-1, matrix metalloproteinase 9, PAI-1, and lipoprotein(a) predicted ILA progression independently of vascular risk factors. Of them, only CRP (CRP>5.5 mg/L; HR, 5.4 [2.3 to 12.7]; P=0.0001) and PAI-1 (PAI-1>23.1 ng/mL; HR, 2.4 [1.0 to 5.8]; P=0.05) predicted ILA progression also independently of the other studied molecules. Progression of symptomatic ILA is associated with a proinflammatory state, as reflected by high levels of inflammatory markers, and with defective fibrinolysis, as indicated by raised concentrations of endogenous fibrinolysis inhibitors.

CT Angiographic Appearance of In-Stent Restenosis of Intracranial Arteries Treated with the Wingspan Stent

Four patients underwent angioplasty and stenting of medically refractory symptomatic intracranial atherosclerosis with the new Wingspan stent system. In all 4 patients, CT angiography (CTA) showed an abnormality within the stented segment that was suggestive of nonocclusive in-stent thrombus. However, subsequent conventional angiography findings were typical for in-stent restenosis. The CTA imaging features of in-stent restenosis are important to recognize, and the misinterpretation of in-stent restenosis as in-stent thrombus may result in inappropriate management.

Leukocyte Count and Vascular Risk in Symptomatic Intracranial Atherosclerosis

Background: Few data exist about the prognostic value of serum white blood cell (WBC) count among patients with symptomatic cerebrovascular disease. We investigated the relationship between WBC count and vascular risk in patients with symptomatic intracranial atherosclerotic disease enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease(WASID) study. Methods: The relationships between baseline serum WBC count (categorized into quartiles) and both ischemic stroke alone and the combined endpoint of ischemic stroke, myocardial infarction or vascular death were evaluated using the log-rank test and Cox proportional hazards regression. Results: Compared with the quartile with the lowest WBC counts at baseline (≤5.9 × 10⁹/l), WASID subjects in both upper WBC quartiles (7.3–8.8; ≧8.9 × 10⁹/l) were more likely to be younger (p = 0.022), diabetic (p = 0.013), on statin treatment (p = 0.015), or have higher mean body mass index (p = 0.015) and triglyceride (p = 0.0065) values. The rate of the primary endpoint was greater among WASID subjects in the upper two WBC quartiles compared with the lower two quartiles (28 vs. 16%, hazard ratio = 1.7; 95% CI = 1.2–2.5, p = 0.003). After adjusting for baseline factors found to be significantly related to the time of primary endpoint in multivariate analysis, both upper WBC quartiles (vs. lowest quartile) were independently associated with a greater risk for the primary endpoint (hazard ratio of 1.5; 95% CI = 1.06–2.2, p = 0.024). Conclusions: An elevated WBC count at study entry was associated with an increased risk of stroke and vascular death in patients with symptomatic intracranial atherosclerotic disease enrolled in the WASID trial.

Prognostic Value of Myocardial Perfusion Gated SPECT in Patients with Symptomatic Intracranial Large-Artery Atherosclerosis

Background: We aimed to evaluate the prognostic value of myocardial perfusion gated SPECT in patients with symptomatic intracranial large-artery atherosclerosis (ILA). Methods: Seventy-two consecutive first-ever symptomatic ILA patients without known heart disease underwent a stress myocardial perfusion gated SPECT, and long-term follow-up was conducted thereafter. Results: During an average follow-up of 15.2 ± 9 months, 9 patients (13.8%) presented major coronary events (CEs). Survival analyses (Kaplan-Meier and Cox regression) identified presence of moderate-to-severe myocardial perfusion defects (log rank p = 0.004) and ejection fraction <50% (p = 0.014) as predictors of future CEs. Neurovascular ischemic events were not predicted by SPECT variables. Conclusion: Myocardial perfusion scintigraphy predicts future CEs in patients with symptomatic ILA and may be helpful to guide therapeutic strategies in this subgroup of stroke patients.

Emerging Endovascular Therapies for Symptomatic Intracranial Atherosclerotic Disease

Marc Fisher MD Section Editor Over the past 2 decades there has been an exponential growth in the scope of disease processes amenable to neuroendovascular treatment. The number and sophistication of the available devices and correspondingly the number of patients undergoing treatment has expanded accordingly. The development and implementation of these new procedures has in some cases outpaced our ability to carefully assess their merits. In comparison to peripheral and coronary vascular disease, neurovascular lesions are less common and far more heterogeneous, ranging from acquired cerebrovascular ischemic disease to hemorrhagic congenital arteriovenous malformations. Each individual disease process (eg, cerebral aneurysm) is composed of a myriad of lesions with different anatomical and pathophysiological characteristics. The natural history of these lesions and their subtypes are likewise poorly defined. For these reasons, personal bias, institutional custom, and anecdotal experience rather than scientific evidence have played a dominant role in guiding therapy. We must move toward collaborative multi-center efforts, prospective data collection and well designed randomized controlled trials to mature as a field over the coming decades. In some ways, symptomatic intracranial atherosclerotic disease (SxICAD) represents an optimal disease process with which to establish this progress toward evidenced based treatment. SxICAD is considerably less heterogeneous than other cerebrovascular disease processes and is arguably best suited as a paradigm for study. In the current article we have attempted to review the available evidence describing the natural history of medically treated SxICAD to determine those patients best suited for invasive treatment strategies. We will also discuss the available treatment modalities which may represent viable options to medical therapy. These data form the basis for the design of future prospective multicenter studies to evaluate the relative merits of interventional treatment. Any invasive treatment strategy for symptomatic intracranial atherosclerosis must satisfy two criteria to establish viability as a …

Adiponectin levels in patients with intracranial atherosclerosis

Adiponectin is a protein secreted by adipose cells that improves insulin sensitivity and possesses antiatherogenic properties. In this study, we investigated the relationship between adiponectin levels and ischemic stroke subtype. Using clinical, imaging, and laboratory data, 231 consecutive patients admitted to a university medical center over a 2-year period with acute cerebral infarcts were categorized into four subtypes: intracranial atherosclerosis (n = 67), extracranial atherosclerosis (n = 61), small arterial occlusion (n = 63), and cardioembolic (n = 40). Clinical features, risk factors including the presence of metabolic syndrome, and levels of s-adiponectin were compared between groups. Patients with more severe metabolic abnormalities were more likely to have lower s-adiponectin levels (p = 0.002). S-adiponectin levels differed by stroke subtype: highest in the cardioembolic group and lowest in the intracranial atherosclerosis group (8.42 +/- 5.07 vs 5.60 +/- 2.79 microg/mL, p = 0.01). Extracranial atherosclerosis (6.45 +/- 4.10 microg/mL) and small arterial occlusion (6.07 +/- 3.44 microg/mL) groups were intermediate. Patients with advanced intracranial atherosclerosis (> or =1 additional lesion outside the symptomatic arterial territory) had lower s-adiponectin levels than those with isolated intracranial atherosclerosis (4.95 +/- 2.63 vs 6.13 +/- 2.84 microg/mL, p = 0.003). In multiple regression analysis, s-adiponectin levels, but not metabolic syndrome, were independently associated with intracranial atherosclerosis. Symptomatic intracranial atherosclerosis is associated with lower s-adiponectin levels vs other ischemic stroke subtypes.

Intracranial Atherosclerotic Disease; Current Options for Surgical or Medical Treatment

Recently, intracranial atherosclerosis has become a major cause of ischemic stroke, appearing more frequently in Koreans than Caucasians. Symptomatic or asymptomatic intracranial atherosclerosis is a disease that could recur readily even during the treatment with anti-platelet agents. When the symptoms develop, ischemic stroke can not be recovered readily. Therefore, aggressive treatments such as endovascular therapy and bypass surgery are required in addition to medical treatment for the intracranial artery stenosis. Recent intracranial stenting and drug eluting stenting have shown as very advanced effective therapeutic modalities. Nevertheless, until now, a randomized controlled study has not been conducted. Regarding bypass surgery, since the failed EC-IC bypass surgery study performed 20 years ago, extensive studies on its efficacy has not been conducted yet, and thus it has to be performed strictly only in hemodynamically compromised patients. Unless breakthrough drugs that suppress the progression of intracranial atherosclerosis and the formation of thrombi, and facilitate the regression of the arterial stenosis, the treatment concept of the recovery of the blood flow of stenotic arterial territory by mechanical recanalization or bypass surgery would be remained for the prevention as well as treatment of ischemic stroke caused by intracranial atherosclerosis.

Current Concepts in the Management of Intracranial Atherosclerotic Disease

Medically refractory, symptomatic intracranial atherosclerotic disease has a poor prognosis. Based on the results of the Warfarin-Aspirin Symptomatic Intracranial Disease study, the risk of ipsilateral stroke at 1.8 years is between 13 and 14% in patients with symptomatic intracranial atherosclerosis. Synergistic advances in intracranial angioplasty and stenting, modern neuroimaging techniques, and periprocedural and postprocedural antithrombotic regimens are creating new models for the diagnosis and successful endovascular treatment of intracranial stenosis. In this article, the most recent clinical developments and concepts for the diagnosis and endovascular treatment of intracranial atherosclerotic disease are discussed.

Management of Patients with Symptomatic Intracranial Atherosclerosis

Intracranial atherosclerosis is a common cause of stroke, accounting for about 50% of ischaemic stroke in Asia and 8% in North America. Many prospective studies have confirmed that intracranial stenosis is an independent predictor for poor outcomes such as recurrent vascular event and death, despite the use of antiplatelet agents. The annual event rate is about 15% per year. The dismal outcome prompts the study of more aggressive treatment strategies, including warfarin and endovascular intervention. We have reviewed the published literature for the treatment of symptomatic intracranial stenosis. The Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial and Warfarin-Aspirin Recurrent Stroke Study (WARSS) studies failed to show that oral anticoagulation was better than aspirin in IAS. Initial encouraging results were found in the use of dual antiplatelet therapy in arresting the progression of stenosis. The results of the endovascular studies are mixed: there are more encouraging results with recent advances of technology in stent design, but a randomized controlled study is still lacking. Although there is still no established therapy for IAS, the results of ongoing randomized clinical trials to study dual antiplatelet agents and the use of endovascular intervention may soon provide clinicians with more evidence to better manage patients with this condition.

Drug-Eluting Stents for the Treatment of Intracranial Atherosclerosis

Intracranial stenting is associated with a 32% rate of restenosis. Drug-eluting stents (DES) have revolutionized the treatment of coronary artery disease and have greatly reduced the risk of in-stent stenosis. We present our experience with the feasibility and safety of using DES for patients with symptomatic intracranial atherosclerosis. All of the patients had >70% stenoses and had failed maximal medical therapy. They were pretreated with aspirin, clopidogrel, and intraprocedural heparin. All of the lesions were predilated, and balloons and stents were slightly undersized. Clopidogrel and aspirin were continued for 1 year, and patients had clinical follow-up and vascular imaging at 30 days, 6 months, and 1 year. Eight patients with intracranial internal carotid artery (3), middle cerebral (2), basilar (2), and vertebral artery (1) stenoses were successfully treated with 4 Cypher (Cordis Corp) and 4 Taxus (Boston Scientific Inc) stents. The mean stenosis severity was reduced from 84.4%+/-10.2% to 2.5%+/-4.6%. One patient had an intraprocedural retinal embolism, but there were no other complications. Over a mean follow-up of 11.1+/-4.9 months (range, 2 to 17.3 months), patients have had repeat angiography (5) or transcranial Doppler with or without CT angiography (3). None of the patients have had clinical or significant angiographic restenosis or required target vessel revascularization. Elective intracranial stenting with DES appears to be feasible and safe, but additional clinical experience is required to assess its efficacy.

Recent advances in endoluminal revascularization for intracranial atherosclerotic disease

More than 750,000 strokes occur annually in the United States. Of these, 8–10% are due to intracranial atherosclerosis. Less than 50% of patients with strokes from intracranial atherosclerosis will have a transient ischemic attack. For those patients with symptomatic intracranial atherosclerosis, the prognosis is poor; and the recent Warfarin-Aspirin Symptomatic Intracranial Stenosis (WASID) trial results have demonstrated the high risk of warfarin without clear benefit. Intracranial angioplasty and stenting is emerging as a viable and effective treatment alternative for patients with symptomatic intracranial stenosis. Advances in stent design, endovascular wires, and catheters and balloons are allowing endovascular surgeons to safely treat intracranial atherosclerosis. Wider clinical experience has led to refinement of patient selection and endoluminal techniques. Drug eluting-stents have the promise of decreasing the risk of restenosis. In this review, the most recent clinical, laboratory, and technical details for the treatment of intracranial angioplasty and stenting are discussed.

Silent Myocardial Ischemia in Patients With Symptomatic Intracranial Atherosclerosis

Optimization of coronary risk evaluation in stroke patients has been encouraged. The relationship between symptomatic intracranial atherosclerosis and occult coronary artery disease (CAD) has not been evaluated sufficiently. We aimed to investigate the prevalence of silent myocardial ischemia in patients with symptomatic intracranial atherosclerosis and to identify factors associated with its presence. From 186 first-ever transient ischemic attack or ischemic stroke patients with intracranial stenoses, 65 fulfilled selection criteria, including angiographic confirmation of a symptomatic atherosclerotic stenosis and absence of known CAD. All patients underwent a maximal-stress myocardial perfusion single-photon emission computed tomography (SPECT). Lipoprotein(a) [Lp(a)], C-reactive protein, and homocysteine (Hcy) levels were determined before SPECT. Stress-rest SPECT detected reversible myocardial perfusion defects in 34 (52%) patients. Vascular risk factors associated with a pathologic SPECT were hypercholesterolemia (P=0.045), presence of >2 risk factors (P=0.004) and high Lp(a) (P=0.023) and Hcy levels (P=0.018). Ninety percent of patients with high Lp(a) and Hcy levels had a positive SPECT. Existence of a stenosed intracranial internal carotid artery (ICA; odds ratio [OR], 7.22, 2.07 to 25.23; P=0.002) and location of the symptomatic stenosis in vertebrobasilar arteries (OR, 4.89, 1.19 to 20.12; P=0.027) were independently associated with silent myocardial ischemia after adjustment by age, sex, and risk factors. More than 50% of the patients with symptomatic intracranial atherosclerosis and not overt CAD show myocardial perfusion defects on stress-rest SPECT. Stenosed intracranial ICA, symptomatic vertebrobasilar stenosis and presence of high Lp(a) and Hcy levels may characterize the patients at a higher risk for occult CAD.