Ameliorating Racial Disparities in Vascular Risk Factor Management With Aggressive Medical Management in the SAMMPRIS Trial.

BACKGROUND: The WASID trial (Warfarin-Aspirin Symptomatic Intracranial Disease) and the SAMMPRIS trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis) evaluated optimal management of symptomatic intracranial atherosclerotic stenosis. The aim of this retrospective, observational study was to determine whether aggressive medical management used in the SAMMPRIS trial ameliorated disparities in risk factor control between Black and non-Black patients. METHODS: The SAMMPRIS trial was a randomized controlled trial that enrolled patients with symptomatic intracranial atherosclerotic stenosis between November 2008 and April 2011. The frequency of risk factors at study entry (baseline) and mean levels of systolic blood pressure, diastolic blood pressure, LDL (low-density lipoprotein), hemoglobin A1c, and exercise level (quantified by physician-based assessment and counseling for exercise score) at baseline and at 1 year of follow-up were compared between Black (n=104) versus non-Black patients (n=347). RESULTS: Significant differences at baseline in Black patients (listed first) versus non-Black patients were age (57.5 versus 61.0 years; P=0.004), hypertension (95.2% versus 87.5%; P=0.027), diabetes (52.9% versus 39.7%; P=0.017), mean diastolic blood pressure (82.4 versus 79.5 mm Hg; P=0.035), and mean physician-based assessment and counseling for exercise score (2.7 versus 3.3; P=0.002). The mean diastolic blood pressure and mean physician-based assessment and counseling for exercise scores at 1 year in Black versus non-Black patients were 74.7 versus 75.5 mm Hg (P=0.575) and 4.2 versus 4.1 (P=0.593), respectively. No disparities in other modifiable risk factors emerged at 1 year. CONCLUSIONS: Significant differences in important risk factors (physical activity and diastolic blood pressure) at baseline between Black and non-Black patients resolved at 1 year, suggesting that aggressive medical management may have an important role in ameliorating disparities in risk factor control between Black and non-Black patients.

Infarct Recurrence in Intracranial Atherosclerosis: Results from the MyRIAD Study.

BACKGROUND: Intracranial atherosclerotic disease (ICAD) is a common cause of ischemic stroke with a high risk of clinical stroke recurrence. Multiple mechanisms may underlie cerebral ischemia in this condition. The study's objective is to discern the mechanisms of recurrent ischemia in ICAD through imaging biomarkers of impaired antegrade flow, poor distal perfusion, abnormal vasoreactivity, and artery-to-artery embolism. METHODS: This prospective multicenter observational study enrolled patients with recent (≤21 days) ischemic stroke or transient ischemic attack (TIA) caused by ICAD with 50-99% stenosis treated medically. We obtained baseline quantitative MRA (QMRA), perfusion MRI (PWI), transcranial Doppler vasoreactivity (VMR), and emboli detection studies (EDS). The primary outcome was ischemic stroke in the territory of the stenotic artery within 1 year of follow-up; secondary outcomes were TIA at 1 year and new infarcts in the territory on MRI at 6-8 weeks. RESULTS: Amongst 102 of 105 participants with clinical follow-up (mean 253±131 days), the primary outcome occurred in 8.8% (12.7/100 patient-years), while 5.9% (8.5/100 patient-years) had a TIA. A new infarct in the territory of the symptomatic artery was noted in 24.7% at 6-8 weeks. A low flow state on QMRA was noted in 25.5%, poor distal perfusion on PWI in 43.5%, impaired vasoreactivity on VMR in 67.5%, and microemboli on EDS in 39.0%. No significant association was identified between these imaging biomarkers and primary or secondary outcomes. CONCLUSIONS: Despite intensive medical management in ICAD, there is a high risk of clinical cerebrovascular events at 1 year and an even higher risk of new imaging-evident infarcts in the subacute period after index stroke. Hemodynamic and plaque instability biomarkers did not identify a higher risk group. Further work is needed to identify mechanisms of ischemic stroke and infarct recurrence and their consequence on long-term physical and cognitive outcomes. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02121028.

Rationale, Design, and Implementation of Intensive Risk Factor Treatment in the CREST2 Trial.

BACKGROUND AND PURPOSE: The CREST2 trial (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis) is comparing intensive medical management (IMM) alone to IMM plus revascularization with carotid endarterectomy or transfemoral carotid artery stenting for preventing stroke or death within 44 days after randomization or ipsilateral ischemic stroke thereafter. There are extensive clinical trial data on outcomes after revascularization of asymptomatic carotid stenosis, but not for IMM. As such, the experimental treatment in CREST2 is IMM, which is described in this article. METHODS: IMM consists of aspirin 325 mg/day and intensive risk factor management, primarily targeting systolic blood pressure <130 mm Hg (initially systolic blood pressure <140 mm Hg) and LDL (low-density lipoprotein) cholesterol <70 mg/dL. Secondary risk factor targets focus on tobacco smoking, non-HDL (high-density lipoprotein), HbA1c (hemoglobin A1c), physical activity, and weight. Risk factor management is performed by site personnel and a lifestyle coaching program delivered by telephone. We report interim risk factor data on 1618 patients at baseline and last follow-up through 24 months. RESULTS: The mean baseline LDL of 80.5 mg/dL improved to 66.7 mg/dL. The mean baseline systolic blood pressure of 139.7 mm Hg improved to 130.3 mm Hg. The proportion of patients in-target improved from 43% to 61% for systolic blood pressure <130 mm Hg and from 45% to 67% for LDL<70 mg/dL (both changes P<0.001). CONCLUSIONS: The rigorous multimodal approach to intensive stroke risk factor management in CREST2 has resulted in significant improvements in risk factor control that will enable a comparison of cutting-edge medical care to revascularization in patients with asymptomatic carotid stenosis. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02089217.

Effects of Spaceflight on Astronaut Brain Structure as Indicated on MRI.

BACKGROUND: There is limited information regarding the effects of spaceflight on the anatomical configuration of the brain and on cerebrospinal fluid (CSF) spaces. METHODS: We used magnetic resonance imaging (MRI) to compare images of 18 astronauts' brains before and after missions of long duration, involving stays on the International Space Station, and of 16 astronauts' brains before and after missions of short duration, involving participation in the Space Shuttle Program. Images were interpreted by readers who were unaware of the flight duration. We also generated paired preflight and postflight MRI cine clips derived from high-resolution, three-dimensional imaging of 12 astronauts after long-duration flights and from 6 astronauts after short-duration flights in order to assess the extent of narrowing of CSF spaces and the displacement of brain structures. We also compared preflight ventricular volumes with postflight ventricular volumes by means of an automated analysis of T1-weighted MRIs. The main prespecified analyses focused on the change in the volume of the central sulcus, the change in the volume of CSF spaces at the vertex, and vertical displacement of the brain. RESULTS: Narrowing of the central sulcus occurred in 17 of 18 astronauts after long-duration flights (mean flight time, 164.8 days) and in 3 of 16 astronauts after short-duration flights (mean flight time, 13.6 days) (P<0.001). Cine clips from a subgroup of astronauts showed an upward shift of the brain after all long-duration flights (12 astronauts) but not after short-duration flights (6 astronauts) and narrowing of CSF spaces at the vertex after all long-duration flights (12 astronauts) and in 1 of 6 astronauts after short-duration flights. Three astronauts in the long-duration group had optic-disk edema, and all 3 had narrowing of the central sulcus. A cine clip was available for 1 of these 3 astronauts, and the cine clip showed upward shift of the brain. CONCLUSIONS: Narrowing of the central sulcus, upward shift of the brain, and narrowing of CSF spaces at the vertex occurred frequently and predominantly in astronauts after long-duration flights. Further investigation, including repeated postflight imaging conducted after some time on Earth, is required to determine the duration and clinical significance of these changes. (Funded by the National Aeronautics and Space Administration.).

Dual Antiplatelet Therapy Beyond 90 days in Symptomatic Intracranial Stenosis in the SAMMPRIS Trial.

BACKGROUND: The safety and efficacy of dual antiplatelet use for symptomatic intracranial atherosclerosis beyond 90 days is unknown. Data from SAMMPRIS was used to determine if dual antiplatelet therapy (DAPT) beyond 90 days impacted the risk of ischemic stroke and hemorrhage. METHODS: This post hoc exploratory analysis from SAMMPRIS included patients who did not have a primary endpoint within 90 days after enrollment (n = 397). Patients in both the aggressive medical management (AMM) and percutaneous transluminal angioplasty and stenting (PTAS) arms were included. Baseline features and outcomes during follow-up were compared between patients who remained on DAPT beyond 90 days (on clopidogrel) and patients who discontinued clopidogrel and remained on aspirin alone at 90 days (off clopidogrel) using Fisher's exact tests. RESULTS: The stroke rate was numerically lower in the group on clopidogrel vs off clopidogrel among both the AMM alone arm (6.0% versus 10.8%, p = 0.31) and the PTAS arm (8.7% versus 9.8%; p = 0.82), but the difference was not significant. The major hemorrhage rates were numerically higher in the group on clopidogrel vs. off clopidogrel group among both the AMM alone arm (4.0% versus 2.5%; p = 0.67) and the PTAS arm (10.9% versus 3.5%; p = 0.08), but were not significant. CONCLUSION: This exploratory analysis suggests that prolonged DAPT use may lower the risk of stroke in medically treated patients with intracranial stenosis but may increase the risk of major hemorrhage.

Relationship Between Vascular Risk Factors and Location of Intracranial Atherosclerosis in the SAMMPRIS Trial.

BACKGROUND: Previous studies have reported that different locations of intracranial atherosclerosis (ICAS) are associated with different demographic features and vascular risk factors. We aimed to examine this observation in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial population. METHODS: SAMMPRIS was a randomized controlled trial that enrolled 451 patients with recent transient ischemic attack or stroke-related due to severe (70%-99%) stenosis of a major intracranial artery. We compared the baseline demographic features and vascular risk factors between the symptomatic artery locations. Wilcoxon test was used to compare continuous variables, and chi-square test was used for categorical variables. RESULTS: Of 449 patients included in the analysis; 289 (64.4%) had ICAS in the anterior circulation and 160 (35.6%) in the posterior circulation. Features that were significantly different between patients with anterior versus posterior ICAS were: median age (58.3 years versus 64.0 years, P < .001), males/females (52.9%/47.1% versus 74.4%/25.6% P < .001), white/black (66.8%/26.6% versus 79.4%/16.9%, P = .02), and history of hyperlipidemia (85.5% versus 92.5%, P = .03). CONCLUSIONS: The observed differences in the distribution of demographic characteristics and vascular risk factors depending on the location of symptomatic ICAS suggest the possibility of different underlying pathological processes involved in the formation of atherosclerotic plaques in different locations.

Mitigating the effects of COVID-19 pandemic on controlling vascular risk factors among participants in a carotid stenosis trial.

INTRODUCTION: The COVID-19 pandemic has presented challenges to managing vascular risk factors with in-person follow-up of patients with asymptomatic carotid stenosis enrolled in the CREST2 trial. CREST2 is comparing intensive medical management alone versus intensive medical management plus revascularization with endarterectomy or stenting. We performed a study to evaluate the feasibility of a home-based program for testing blood pressure (BP) and low-density lipoprotein (LDL) in CREST2. METHODS: This study involved 45 patients at 10 sites in the CREST2 trial. The initial patients were identified by the Medical Management Core (MMC) as high-risk patients defined by stage 2 hypertension, LDL > 90 mg/dl, or both. If a patient at the site declined participation, another was substituted. All patients who agreed to participate were sent a BP monitoring device and a commercially available at-home lipid test kit that uses a self-performed finger-stick blood sample that was resulted to the patient. Training on the use of the equipment and obtaining the risk factor results was done by the study coordinator by telephone. RESULTS: Ten of the 130 currently active CREST2 sites participated, 8 in the LDL portion and 5 in the BP portion (3 sites did both). Twenty-six BP devices and 23 lipid tests were sent to patients. Of the 26 patients who obtained BP readings with the devices, 9 were out of the study target and adjustments in BP medications were made in 3. Of the 23 patients sent LDL tests, 13 were able to perform the test showing 7 were out of target, leading to adjustments in lipid medications in 4. CONCLUSION: This study established the feasibility of at-home monitoring of BP and LDL in a clinical trial and identified implementation challenges prior to widespread use in the trial. (ClinicalTrials.gov number NCT02089217).

Mechanisms of early Recurrence in Intracranial Atherosclerotic Disease (MyRIAD): Rationale and design.

RATIONALE: Intracranial atherosclerotic disease (ICAD) is the most common cause of ischemic stroke with the highest rate of recurrence, despite aggressive medical management. Diverse mechanisms may be responsible for ICAD-related cerebral ischemia, with potential therapeutic implications. Here we present the rationale, design and methods of the Mechanisms of Early Recurrence in Intracranial Atherosclerotic Disease (MyRIAD) study. The aim of MyRIAD is to determine the mechanisms of stroke in ICAD through physiologic imaging biomarkers that evaluate impaired antegrade flow, poor distal perfusion, abnormal vasoreactivity, artery to artery embolism, and their interaction. METHODS AND DESIGN: This is a prospective observational study of patients with recently symptomatic (<21 days) ICAD with 50-99% stenosis treated medically and monitored for up to 1 year. An estimated 110 participants are recruited at 10 sites to identify the association between the presence of each mechanism of ischemia and recurrent stroke. The primary outcome is ischemic stroke in the territory of the symptomatic artery. Secondary outcomes include new cerebral infarction on MRI at 6-8 weeks and recurrent TIA in the territory of the symptomatic artery. DISCUSSION: MyRIAD is positioned to define the role of specific mechanisms of recurrent ischemia in patients with symptomatic ICAD. This knowledge will allow the development and implementation of effective and specific treatments for this condition.

Hemodynamic Markers in the Anterior Circulation as Predictors of Recurrent Stroke in Patients With Intracranial Stenosis.

Background and Purpose- Although aggressive medical therapy was superior to stenting in the SAMMPRIS trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis), the stroke rate in the medical arm was still high. The aim of this study was to determine the association between hemodynamic markers (borderzone infarct pattern and impaired collateral flow on baseline imaging) and rates of recurrent stroke in patients treated medically in SAMMPRIS. Methods- This was a post hoc analysis of patients whose qualifying event for SAMMPRIS was an infarct in the territory of a stenotic middle cerebral artery or intracranial carotid artery. Infarcts were adjudicated as involving primarily internal or cortical borderzone territories, the core middle cerebral artery territory, or perforator territories, and collateral flow was assessed according to a standard scale (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology). Log-rank tests and χ2 tests were performed to assess associations of infarct patterns and collateral flow with rates of recurrent stroke. Results- Of 101 patients who qualified, 14 of 53 (26.4%) with borderzone infarcts, 2 of 24 (8.3%) with core middle cerebral artery infarcts, and 3 of 24 (12.5%) with perforator infarcts had a recurrent stroke in the territory (P=0.14 for comparing the 3 groups, P=0.052 for borderzone versus nonborderzone). Of 82 patients with collateral flow assessment, 30 of 43 (70%) with borderzone infarcts, 7 of 19 (37%) with core middle cerebral artery infarcts, and 11 of 20 (55%) with perforator infarcts had impaired collateral flow distal to the stenosis (P=0.049). Patients with borderzone infarcts and impaired collateral flow had the highest risk of recurrent stroke (37%). Conclusions- Borderzone infarcts and impaired collateral flow identify a subgroup of patients with intracranial stenosis who are at particularly high risk of recurrent stroke on medical treatment. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT00576693.

Stroke Caused by Atherosclerosis of the Major Intracranial Arteries.

Our goal in this review is to discuss the pathophysiology, diagnosis, and treatment of stroke caused by atherosclerosis of the major intracranial arteries. References for the review were identified by searching PubMed for related studies published from 1955 to June 2016 using search terms intracranial stenosis and intracranial atherosclerosis. Reference sections of published randomized clinical trials and previously published reviews were searched for additional references. Intracranial atherosclerotic disease is a highly prevalent cause of stroke that is associated with a high risk of recurrent stroke. It is more prevalent among blacks, Hispanics, and Asians compared with whites. Diabetes mellitus, hypertension, metabolic syndrome, smoking, hyperlipidemia, and a sedentary lifestyle are the major modifiable risk factors associated with intracranial atherosclerotic disease. Randomized clinical trials comparing aggressive management (dual antiplatelet treatment for 90 days followed by aspirin monotherapy and intensive management of vascular risk factors) with intracranial stenting plus aggressive medical management have shown medical management alone to be safer and more effective for preventing stroke. As such, aggressive medical management has become the standard of care for symptomatic patients with intracranial atherosclerotic disease. Nevertheless, there are subgroups of patients who are still at high risk of stroke despite being treated with aggressive medical management. Future research should aim to establish clinical, serological, and imaging biomarkers to identify high-risk patients, and clinical trials evaluating novel therapies should be focused on these patients.

Impact of Baseline Features and Risk Factor Control on Cognitive Function in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial.

BACKGROUND: Cerebrovascular disease is an important cause of cognitive impairment. The aim of this study is to report the relationship between cognitive function and risk factors at baseline and during follow-up in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial. METHODS: Subjects in the SAMMPRIS trial were included in this study. In order to have an assessment of cognitive function independent of stroke, patients with a stroke as a qualifying event whose deficits included aphasia or neglect were excluded from these analyses as were those with a cerebrovascular event during follow-up. The Montreal Cognitive Assessment (MoCA) score was used to assess cognitive impairment at baseline, 4 months, 12 months and closeout. Cognitive impairment was defined as MoCA < 26. A multivariate analysis was performed to determine what risk factors were independent predictors of cognitive function at baseline, 12 months and closeout. Among patients randomized to aggressive medical management only, the percentage of patients with cognitive impairment was compared between patients in versus out of target for each risk factor at 12 months and closeout. RESULTS: Of the 451 patients in SAMMPRIS, 371 patients met the inclusion criteria. MoCA < 26 was present in 55% at baseline. Older age and physical inactivity were associated with cognitive impairment at baseline. Older age, non-white race, lower baseline body mass index, and baseline cognitive impairment were associated with cognitive impairment at 12 months. In the aggressive medical management group, at 12 months, physical inactivity during follow-up was the strongest risk factor associated with cognitive impairment. CONCLUSION: Cognitive impairment is common in patients with severe symptomatic intracranial atherosclerosis. Physical inactivity at baseline and during follow-up is a strong predictor of cognitive impairment.

Relationship between Risk Factor Control and Compliance with a Lifestyle Modification Program in the Stenting Aggressive Medical Management for Prevention of Recurrent Stroke in Intracranial Stenosis Trial.

BACKGROUND: Lifestyle modification programs have improved the achievement of risk factor targets in a variety of clinical settings, including patients who have previously suffered a stroke or transient ischemic attack and those with multiple risk factors. Stenting Aggressive Medical Management for Prevention of Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) was the first vascular disease prevention trial to provide a commercially available lifestyle modification program to enhance risk factor control. We sought to determine the relationship between compliance with this program and risk factor control in SAMMPRIS. METHODS: SAMMPRIS aggressive medical management included a telephonic lifestyle modification program provided free of charge to all subjects (n = 451) during their participation in the study. Subjects with fewer than 3 expected lifestyle-coaching calls were excluded from these analyses. Compliant subjects (n = 201) had greater than or equal to 78.5% of calls (median % of completed/expected calls). Noncompliant subjects (n = 200) had less than 78.5% of calls or refused to participate. Mean risk factor values or % in-target for each risk factor was compared between compliant versus noncompliant subjects, using t tests and chi-square tests. Risk factor changes from baseline to follow-up were compared between the groups to account for baseline differences. RESULTS: Compliant subjects had better risk factor control throughout follow-up for low-density lipoprotein, systolic blood pressure (SBP), hemoglobin A1c (HgA1c), non-high-density lipoprotein, nonsmoking, and exercise than noncompliant subjects, but there was no difference for body mass index. After adjusting for baseline differences between the groups, compliant subjects had a greater change from baseline than noncompliant subjects for SBP did at 24 months and HgA1c at 6 months. CONCLUSION: SAMMPRIS subjects who were compliant with the lifestyle modification program had better risk factor control during the study for almost all risk factors.

Nonprocedural Symptomatic Infarction and In-Stent Restenosis After Intracranial Angioplasty and Stenting in the SAMMPRIS Trial (Stenting and Aggressive Medical Management for the Prevention of Recurrent Stroke in Intracranial Stenosis).

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the frequency of symptomatic in-stent restenosis (ISR) and its contribution to nonprocedural symptomatic infarction in the SAMMPRIS trial (Stenting and Aggressive Medical Management for the Prevention of Recurrent Stroke in Intracranial Stenosis). METHODS: Patients without a periprocedural primary end point were followed up to determine the occurrence of any of the following events: ischemic stroke, cerebral infarct with temporary signs, or transient ischemic attack in the territory of the stented artery. Vascular imaging performed after these events was reviewed for ISR. Annual rates for symptomatic ISR were calculated using Kaplan-Meier estimates. RESULTS: Of 183 patients in the stenting group without a periprocedural primary end point, 27 (14.8%) had a symptomatic infarction (stroke or cerebral infarct with temporary signs) and 16 (8.7%) had transient ischemic attack alone in the territory during a median follow-up of 35.0 months. Of the 27 patients with infarctions, 17 (9.3%) had an ischemic stroke and 10 (5.5%) had a cerebral infarct with temporary signs alone. Adequate vascular imaging to evaluate ISR was available in 24 patients with infarctions (showing ISR in 16 [66.7%]) and in 10 patients with transient ischemic attack alone (showing ISR in 8 [80%]). The 1-, 2-, and 3-year rates (with 95% confidence limits) for symptomatic ISR in the SAMMPRIS stent cohort were 9.6% (6.1%-14.9%), 11.3% (7.5%-17.0%), and 14.0% (9.6%-20.2%), respectively. CONCLUSIONS: Symptomatic ISR occurred in at least 1 of 7 patients in SAMMPRIS by 3 years of follow-up and was likely responsible for the majority of nonprocedural cerebral infarctions. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT00576693.

Is There Benefit from Stenting on Cognitive Function in Intracranial Atherosclerosis?

BACKGROUND: Revascularization of stenotic cerebral arteries is hypothesized to improve cognition by increasing cerebral perfusion. AIMS: We compared cognition impairment among patients treated with percutaneous angioplasty and stenting (PTAS) and aggressive medical management (AMM) versus AMM alone in the Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) Trial. METHODS: In SAMMPRIS, 451 patients with recent transient ischemic attack or stroke attributed to 70-99% intracranial stenosis were randomized to PTAS plus AMM or AMM alone. Patients who had stroke as the qualifying event with National Institutes of Health Stroke Scale indicating aphasia or neglect were excluded from these analyses. Patients with a cerebrovascular event (ischemic stroke, cerebral infarct with temporary signs or intracranial hemorrhage) during follow-up were excluded from follow-up visit analyses. The Montreal Cognitive Assessment (MoCA) score was used to assess cognition impairment at baseline, 4 months, 12 months and closeout. Cognitive impairment was defined as MoCA <26. Mean MoCA scores and the percentage of patients with cognitive impairment were compared between treatment groups at each time point using t tests and chi-square tests. Differences in MoCA mean at baseline and follow-up time points were compared using mixed model repeated measures ANOVA and Tukey-Kramer tests. RESULTS: There were no significant differences between the treatment groups for mean MoCA at any time point. Mean MoCA scores improved in both groups. The percentage of patients with cognitive impairment in the AMM versus PTAS groups was not significantly different at any time point. CONCLUSIONS: Revascularization with PTAS showed no improvement in cognitive impairment over AMM alone among patients who did not have recurrent cerebrovascular events during follow-up.

Postprandial Clearance of Oxidized Low-Density Lipoprotein in Patients with Stroke Due to Atherosclerosis.

BACKGROUND: Oxidized low-density lipoprotein (OxLDL) is a contributor to atherosclerosis development. OxLDL formation increases in the postprandial state due to oxidative stress in subjects with coronary artery disease (CAD) and diabetes, but has not been studied in patients with atherosclerotic stroke. We aimed to determine differences in postprandial OxLDL in patients with atherosclerotic stroke compared to stroke from other causes. METHODS: Patients with ischemic stroke but no history of CAD (n = 42) were enrolled and categorized by stroke subtype as extracranial atherosclerosis (EC), n = 12; intracranial atherosclerosis (IC), n = 16; or other cause, n = 14. After fasting overnight, subjects consumed a standardized fat meal. OxLDL levels were measured at t = 0 and t = 4 hours postprandial using enzyme-linked immunosorbent assay. Comparisons between the mean changes in OxLDL between the groups were performed using the analysis of variance procedure. RESULTS: The IC group had the highest mean baseline level of OxLDL and the greatest decline during the postprandial period. There was a trend toward a difference in the mean change in OxLDL between the 3 groups (P = .0553). Subjects with atherosclerotic stroke (EC and IC groups) had higher fasting OxLDL and had a significant decline in OxLDL compared to those with stroke from other causes (P = .0164). CONCLUSIONS: Subjects with stroke due to atherosclerosis, particularly intracranially, demonstrated high fasting OxLDL and a decline in OxLDL during the postprandial period. This decline in OxLDL may indicate an accelerated clearance of OxLDL resulting from meal-induced oxidative stress.

Impact of the New American Heart Association/American Stroke Association Definition of Stroke on the Results of the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial.

BACKGROUND: An American Heart Association/American Stroke Association (AHA/ASA) writing committee has recently recommended that tissue evidence of cerebral infarction associated with temporary symptoms (CITS) lasting <24 hours should be considered a stroke. We analyzed the impact of considering CITS as equivalent to stroke on the results of the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial. METHODS: We compared outcomes in the medical (n = 227) and stenting (n = 224) groups in SAMMPRIS using the following primary end point (new components in bold): any stroke, CITS, or death within 30 days after enrollment or within 30 days after a revascularization procedure for the qualifying lesion during follow-up; or ischemic stroke or CITS in the territory of the qualifying artery beyond 30 days. We also compared the use of brain magnetic resonance imaging (MRI) after transient ischemic attacks (TIAs) in both treatment groups. RESULTS: By considering CITS as equivalent to stroke, the number of primary end points increased from 34 to 43 in the medical group and from 52 to 66 in the stenting group of SAMMPRIS. The Kaplan-Meier curves for the primary end points in the 2 groups were significantly different (P = .009). The percentage of patients with reported TIAs who underwent brain MRI was 69% in the medical group and 61% in the stenting group (P = .40). CONCLUSION: Using the AHA/ASA definition of stroke resulted in a substantially higher primary end point rate in both treatment groups and an even higher benefit from medical therapy over stenting than originally shown in SAMMPRIS. The higher rate of CITS in the stenting group was not due to ascertainment bias.

Do Patient Characteristics Explain the Differences in Outcome Between Medically Treated Patients in SAMMPRIS and WASID?

BACKGROUND AND PURPOSE: The Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) medical group had a much lower primary end point rate than predicted from the preceding Warfarin Aspirin Symptomatic Intracranial Disease (WASID) trial. This result has been attributed to the aggressive medical therapy used in SAMMPRIS, but an alternative hypothesis is that SAMMPRIS patients were at lower risk. We undertook analyses to evaluate these competing hypotheses. METHODS: Using proportional hazards regression, we compared the SAMMPRIS primary end point between SAMMPRIS medical patients and WASID patients meeting the same qualifying criteria adjusted for confounding baseline characteristics. RESULTS: The unadjusted comparison of the SAMMPRIS primary end point showed a significantly higher risk for WASID patients (P=0.009, logrank test) with 12 month Kaplan-Meier estimates of 21.9% in WASID and 12.6% in SAMMPRIS and hazard ratio 1.9 (95% confidence interval =1.2-3.0). The analyses identified the following confounding factors that varied between the studies and that conferred a higher risk: lack of statin use at enrollment (hazard ratio =1.8, 95% confidence interval =1.1-2.9, P=0.027) that was more prevalent among WASID patients (39% versus 14%, P<0.0001) and prior infarcts in the territory of the symptomatic vessel (hazard ratio =1.8, 95% confidence interval =1.1-2.9, P=0.023) that was more prevalent among SAMMPRIS patients (34% versus 22%, P=0.015).The hazard ratio for WASID versus SAMMPRIS adjusted for these 2 characteristics was 1.9 (95% confidence interval =1.1-3.2). CONCLUSIONS: After adjustment for confounding baseline characteristics, WASID patients had an almost 2-fold higher risk of the SAMMPRIS primary end point, which supports the hypothesis that the lower rate of the primary end point in the medical arm of SAMMPRIS compared with WASID patients was as a result of the aggressive medical management used in SAMMPRIS. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00576693.

Does the Stenting Versus Aggressive Medical Therapy Trial Support Stenting for Subgroups With Intracranial Stenosis?

BACKGROUND AND PURPOSE: Although the Stenting Versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) trial showed that medical therapy alone was superior to stenting plus medical therapy for preventing recurrent strokes in patients with symptomatic intracranial stenosis, we determined whether SAMMPRIS supported the use of stenting in any subpopulations of patients with symptomatic intracranial arterial stenosis. METHODS: The primary outcome, 30-day stroke and death and later strokes in the territory of the qualifying artery, was compared in those with and without baseline factors in the 2 treatment arms, percutaneous transluminal angioplasty and stenting (PTAS) plus aggressive medical therapy versus aggressive medical therapy alone. Baseline factors included sex, age, race, diabetes mellitus, hypertension, lipid disorder, smoking status, type of qualifying event, qualifying event hypoperfusion symptoms, use of antithrombotic or proton pump inhibitor at baseline, days to enrollment, old infarcts in the same territory, percent stenosis, other artery stenosis, and location of the symptomatic artery. RESULTS: A total of 451 patients were enrolled, 227 randomized to aggressive medical therapy and 224 to PTAS. Of all variables evaluated, the observed 2-year event rates were higher with PTAS than with aggressive medical therapy in the vast majority and the interaction with treatment was not statistically significant for any of the factors. CONCLUSIONS: The SAMMPRIS results do not provide evidence to support the use of PTAS using the Wingspan stent system compared with medical treatment in any examined subpopulation of patients with symptomatic intracranial stenosis, including those with qualifying event hypoperfusion symptoms. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00576693.

Outcome in patients previously on antithrombotic therapy in the SAMMPRIS trial: subgroup analysis.

BACKGROUND AND PURPOSE: Stenting has been used as a rescue therapy in patients with intracranial arterial stenosis and a transient ischemic attack or stroke when on antithrombotic therapy (AT). We determined whether the stenting versus aggressive medical therapy for intracranial arterial stenosis (SAMMPRIS) trial supported this approach by comparing the treatments within subgroups of patients whose qualifying event (QE) occurred on versus off of AT. METHODS: The primary outcome, 30-day stroke and death and later strokes in the territory of the qualifying artery, was compared between (1) percutaneous transluminal angioplasty and stenting plus aggressive medical therapy (PTAS) versus aggressive medical management therapy alone (AMM) for patients whose QE occurred on versus off AT and between (2) patients whose QE occurred on versus off AT separately for the treatment groups. RESULTS: Among the 284/451 (63%) patients who had their QE on AT, the 2-year primary end point rates were 15.6% for those randomized to AMM (n=140) and 21.6% for PTAS (n=144; P=0.043, log-rank test). In the 167 patients not on AT, the 2-year primary end point rates were 11.6% for AMM (n=87) and 18.8% for PTAS (n=80; P=0.31, log-rank test). Within both treatment groups, there was no difference in the time to the primary end point between patients who were on or off AT (AMM, P=0.96; PTAS, P=0.52; log-rank test). CONCLUSIONS: SAMMPRIS results indicate that the benefit of AMM over PTAS is similar in patients on versus off AT at the QE and that failure of AT is not a predictor of increased risk of a primary end point. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00576693.