Tenecteplase for Stroke at 4.5 to 24 Hours with Perfusion-Imaging Selection.

BACKGROUND: Thrombolytic agents, including tenecteplase, are generally used within 4.5 hours after the onset of stroke symptoms. Information on whether tenecteplase confers benefit beyond 4.5 hours is limited. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial involving patients with ischemic stroke to compare tenecteplase (0.25 mg per kilogram of body weight, up to 25 mg) with placebo administered 4.5 to 24 hours after the time that the patient was last known to be well. Patients had to have evidence of occlusion of the middle cerebral artery or internal carotid artery and salvageable tissue as determined on perfusion imaging. The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death) at day 90. Safety outcomes included death and symptomatic intracranial hemorrhage. RESULTS: The trial enrolled 458 patients, 77.3% of whom subsequently underwent thrombectomy; 228 patients were assigned to receive tenecteplase, and 230 to receive placebo. The median time between the time the patient was last known to be well and randomization was approximately 12 hours in the tenecteplase group and approximately 13 hours in the placebo group. The median score on the modified Rankin scale at 90 days was 3 in each group. The adjusted common odds ratio for the distribution of scores on the modified Rankin scale at 90 days for tenecteplase as compared with placebo was 1.13 (95% confidence interval, 0.82 to 1.57; P = 0.45). In the safety population, mortality at 90 days was 19.7% in the tenecteplase group and 18.2% in the placebo group, and the incidence of symptomatic intracranial hemorrhage was 3.2% and 2.3%, respectively. CONCLUSIONS: Tenecteplase therapy that was initiated 4.5 to 24 hours after stroke onset in patients with occlusions of the middle cerebral artery or internal carotid artery, most of whom had undergone endovascular thrombectomy, did not result in better clinical outcomes than those with placebo. The incidence of symptomatic intracerebral hemorrhage was similar in the two groups. (Funded by Genentech; TIMELESS ClinicalTrials.gov number, NCT03785678.).

Apixaban to Prevent Recurrence After Cryptogenic Stroke in Patients With Atrial Cardiopathy: The ARCADIA Randomized Clinical Trial.

Importance: Atrial cardiopathy is associated with stroke in the absence of clinically apparent atrial fibrillation. It is unknown whether anticoagulation, which has proven benefit in atrial fibrillation, prevents stroke in patients with atrial cardiopathy and no atrial fibrillation. Objective: To compare anticoagulation vs antiplatelet therapy for secondary stroke prevention in patients with cryptogenic stroke and evidence of atrial cardiopathy. Design, Setting, and Participants: Multicenter, double-blind, phase 3 randomized clinical trial of 1015 participants with cryptogenic stroke and evidence of atrial cardiopathy, defined as P-wave terminal force greater than 5000 µV × ms in electrocardiogram lead V1, serum N-terminal pro-B-type natriuretic peptide level greater than 250 pg/mL, or left atrial diameter index of 3 cm/m2 or greater on echocardiogram. Participants had no evidence of atrial fibrillation at the time of randomization. Enrollment and follow-up occurred from February 1, 2018, through February 28, 2023, at 185 sites in the National Institutes of Health StrokeNet and the Canadian Stroke Consortium. Interventions: Apixaban, 5 mg or 2.5 mg, twice daily (n = 507) vs aspirin, 81 mg, once daily (n = 508). Main Outcomes and Measures: The primary efficacy outcome in a time-to-event analysis was recurrent stroke. All participants, including those diagnosed with atrial fibrillation after randomization, were analyzed according to the groups to which they were randomized. The primary safety outcomes were symptomatic intracranial hemorrhage and other major hemorrhage. Results: With 1015 of the target 1100 participants enrolled and mean follow-up of 1.8 years, the trial was stopped for futility after a planned interim analysis. The mean (SD) age of participants was 68.0 (11.0) years, 54.3% were female, and 87.5% completed the full duration of follow-up. Recurrent stroke occurred in 40 patients in the apixaban group (annualized rate, 4.4%) and 40 patients in the aspirin group (annualized rate, 4.4%) (hazard ratio, 1.00 [95% CI, 0.64-1.55]). Symptomatic intracranial hemorrhage occurred in 0 patients taking apixaban and 7 patients taking aspirin (annualized rate, 1.1%). Other major hemorrhages occurred in 5 patients taking apixaban (annualized rate, 0.7%) and 5 patients taking aspirin (annualized rate, 0.8%) (hazard ratio, 1.02 [95% CI, 0.29-3.52]). Conclusions and Relevance: In patients with cryptogenic stroke and evidence of atrial cardiopathy without atrial fibrillation, apixaban did not significantly reduce recurrent stroke risk compared with aspirin. Trial Registration: ClinicalTrials.gov Identifier: NCT03192215.

High-Density Lipoprotein Carries Markers That Track With Recovery From Stroke.

RATIONALE: Prospective cohort studies question the value of HDL-C (high-density lipoprotein cholesterol) for stroke risk prediction. OBJECTIVE: Investigate the relationship between long-term functional recovery and HDL proteome and function. METHODS AND RESULTS: Changes in HDL protein composition and function (cholesterol efflux capacity) in patients after acute ischemic stroke at 2 time points (24 hours, 35 patients; 96 hours, 20 patients) and in 35 control subjects were measured. The recovery from stroke was assessed by 3 months, the National Institutes of Health Stroke Scale and modified Rankin scale scores. When compared with control subject after adjustments for sex and HDL-C levels, 12 proteins some of which participate in acute phase response and platelet activation (APMAP [adipocyte plasma membrane-associated protein], GPLD1 [phosphate inositol-glycan specific phospholipase D], APOE [apolipoprotein E], IHH [Indian hedgehog protein], ITIH4 [inter-alpha-trypsin inhibitor chain H4], SAA2 [serum amyloid A2], APOA4 [apolipoprotein A-IV], CLU [clusterin], ANTRX2 [anthrax toxin receptor 2], PON1 [serum paraoxonase/arylesterase], SERPINA1 [alpha-1-antitrypsin], and APOF [apolipoprotein F]) were significantly (adjusted P<0.05) altered in stroke HDL at 96 hours. The first 8 of these proteins were also significantly altered at 24 hours. Consistent with inflammatory remodeling, cholesterol efflux capacity was reduced by 32% (P<0.001) at both time points. Baseline stroke severity adjusted regression model showed that changes within 96-hour poststroke in APOF, APOL1, APMAP, APOC4 (apolipoprotein C4), APOM (apolipoprotein M), PCYOX1 (prenylcysteine oxidase 1), PON1, and APOE correlate with stroke recovery scores (R2=0.38-0.73, adjusted P<0.05). APOF (R2=0.73) and APOL1 (R2=0.60) continued to significantly correlate with recovery scores after accounting for tPA (tissue-type plasminogen activator) treatment. CONCLUSIONS: Changes in HDL proteins during early acute phase of stroke associate with recovery. Monitoring HDL proteins may provide clinical biomarkers that inform on stroke recuperation.

Baseline Cognitive Impairment in Patients With Asymptomatic Carotid Stenosis in the CREST-2 Trial.

BACKGROUND AND PURPOSE: Studies of carotid artery disease have suggested that high-grade stenosis can affect cognition, even without stroke. The presence and degree of cognitive impairment in such patients have not been reported and compared with a demographically matched population-based cohort. METHODS: We studied cognition in 1000 consecutive CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) patients, a treatment trial for asymptomatic carotid disease. Cognitive assessment was after randomization but before assigned treatment. The cognitive battery was developed in the general population REGARDS Study (Reasons for Geographic and Racial Differences in Stroke), involving Word List Learning Sum, Word List Recall, and Word List fluency for animal names and the letter F. The carotid stenosis patients were >45 years old with ≥70% asymptomatic carotid stenosis and no history of prevalent stroke. The distribution of cognitive performance for the patients was standardized, accounting for age, race, and education using performance from REGARDS, and after further adjustment for hypertension, diabetes, dyslipidemia, and smoking. Using the Wald Test, we tabulated the proportion of Z scores less than the anticipated deviate for the population-based cohort for representative percentiles. RESULTS: There were 786 baseline assessments. Mean age was 70 years, 58% men, and 52% right-sided stenosis. The overall Z score for patients was significantly below expected for higher percentiles (P<0.0001 for 50th, 75th, and 95th percentiles) and marginally below expected for the 25th percentile (P=0.015). Lower performance was attributed largely to Word List Recall (P<0.0001 for all percentiles) and for Word List Learning (50th, 75th, and 95th percentiles below expected, P≤0.01). The scores for left versus right carotid disease were similar. CONCLUSIONS: Baseline cognition of patients with severe carotid stenosis showed below normal cognition compared to the population-based cohort, controlling for demographic and cardiovascular risk factors. This cohort represents the largest group to date to demonstrate that poorer cognition, especially memory, in this disease. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02089217.

Long-Term Results of Stenting versus Endarterectomy for Carotid-Artery Stenosis.

BACKGROUND: In the Carotid Revascularization Endarterectomy versus Stenting Trial, we found no significant difference between the stenting group and the endarterectomy group with respect to the primary composite end point of stroke, myocardial infarction, or death during the periprocedural period or any subsequent ipsilateral stroke during 4 years of follow-up. We now extend the results to 10 years. METHODS: Among patients with carotid-artery stenosis who had been randomly assigned to stenting or endarterectomy, we evaluated outcomes every 6 months for up to 10 years at 117 centers. In addition to assessing the primary composite end point, we assessed the primary end point for the long-term extension study, which was ipsilateral stroke after the periprocedural period. RESULTS: Among 2502 patients, there was no significant difference in the rate of the primary composite end point between the stenting group (11.8%; 95% confidence interval [CI], 9.1 to 14.8) and the endarterectomy group (9.9%; 95% CI, 7.9 to 12.2) over 10 years of follow-up (hazard ratio, 1.10; 95% CI, 0.83 to 1.44). With respect to the primary long-term end point, postprocedural ipsilateral stroke over the 10-year follow-up occurred in 6.9% (95% CI, 4.4 to 9.7) of the patients in the stenting group and in 5.6% (95% CI, 3.7 to 7.6) of those in the endarterectomy group; the rates did not differ significantly between the groups (hazard ratio, 0.99; 95% CI, 0.64 to 1.52). No significant between-group differences with respect to either end point were detected when symptomatic patients and asymptomatic patients were analyzed separately. CONCLUSIONS: Over 10 years of follow-up, we did not find a significant difference between patients who underwent stenting and those who underwent endarterectomy with respect to the risk of periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke. The rate of postprocedural ipsilateral stroke also did not differ between groups. (Funded by the National Institutes of Health and Abbott Vascular Solutions; CREST ClinicalTrials.gov number, NCT00004732.).

Duration of asymptomatic status and outcomes following carotid endarterectomy and carotid artery stenting in the Carotid Revascularization Endarterectomy vs Stenting Trial.

BACKGROUND: Most carotid revascularization studies define asymptomatic as symptom-free for more than 180 days; however, it is unknown if intervention carries similar risk among those currently asymptomatic but with previous symptoms (PS) vs those who were always asymptomatic (AA). METHODS: We compared the periprocedural and 4-year risks of PS vs AA patients in the Carotid Revascularization Endarterectomy vs Stenting Trial (CREST) randomized to carotid endarterectomy (CEA) or carotid artery stenting (CAS)/angioplasty. Proportional hazards models adjusting for age, sex, and treatment were used to assess the risk of periprocedural stroke and/or death (S+D; any S+D during periprocedural period), stroke and death at 4 years (any S+D within the periprocedural period and ipsilateral stroke out to 4 years) and the primary end point at 4 years (any stroke, death, and myocardial infarction within the periprocedural period and ipsilateral stroke out to 4 years). Analysis was performed pooling the CEA-treated and CAS-treated patients, and separately for each treatment. RESULTS: Of 1181 asymptomatic patients randomized in CREST, 1104 (93%) were AA and 77 (7%) were PS. There was no difference in risk when comparing the AA and PS cohorts in the pooled CAS+CEA population for periprocedural S+D (2.0% vs 1.3%), S+D at 4 years (3.6% vs 3.2%), or the primary end point (5.2% vs 5.8%). There were also no differences among those assigned to CEA (periprocedural S+D, 1.5% vs 0%; S+D at 4 years, 2.7% vs 0%; or primary end point, 5.1% vs 2.4%) or CAS (periprocedural S+D, 2.5% vs 2.8%; S+D at 4 years, 4.4% vs 6.9%; or primary end point, 5.3% vs 9.8%) when analyzed separately. CONCLUSIONS: In CREST, only a small minority of asymptomatic patients had previous ipsilateral symptoms. The outcomes of periprocedural S+D, periprocedural S+D, and ipsilateral stroke up to 4 years, and the primary end point did not differ for AA patients compared with PS patients.

Primary Results of the Multicenter ARISE II Study (Analysis of Revascularization in Ischemic Stroke With EmboTrap).

BACKGROUND AND PURPOSE: EmboTrap is a novel stent retriever designed to achieve rapid and substantial flow restoration in acute ischemic stroke secondary to large-vessel occlusions. Here, we evaluated EmboTrap's safety and efficacy compared with established stent retrievers. METHODS: ARISE II (Analysis of Revascularization in Ischemic Stroke With EmboTrap) was a single-arm, prospective, multicenter study, comparing the EmboTrap device to a composite performance goal criterion derived using a Bayesian meta-analysis from the pivotal SWIFT (Solitaire device) and TREVO 2 (Trevo device) trials. Patients at 11 US and 8 European sites were eligible for inclusion if they had large-vessel occlusions and moderate-to-severe neurological deficits within 8 hours of symptom onset. The primary efficacy end point was achievement of modified Thrombolysis in Cerebral Ischemia (mTICI) reperfusion scores of ≥2b within 3 EmboTrap passes as adjudicated by the core laboratory. The primary safety end point was a composite of symptomatic intracerebral hemorrhage and serious adverse device effects. Secondary end points included functional independence (modified Rankin Scale, 0-2) and all-cause mortality at 90 days. RESULTS: Between October 2015 and February 2017, 227 patients were enrolled and treated with the EmboTrap device. The primary efficacy end point (mTICI ≥2b within 3 passes) was achieved in 80.2% (95% confidence interval, 74%-85% versus 56% performance goal criterion; P value, <0.0001), and mTICI 2c/3 was 65%. After all interventions, mTICI 2c/3 was achieved in 76%, and mTICI ≥2b was 92.5%. The rate of first pass (mTICI ≥2b following a single pass) was 51.5%. The primary safety end point composite rate of symptomatic intracerebral hemorrhage or serious adverse device effects was 5.3%. Functional independence and all-cause mortality at 90 days were 67% and 9%, respectively. CONCLUSIONS: The EmboTrap stent-retriever mechanical thrombectomy device demonstrated high rates of substantial reperfusion and functional independence in patients with acute ischemic stroke secondary to large-vessel occlusions. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02488915.

The Influence of ß-Adrenergic Receptor Kinase-1 on Stroke-induced Immunodeficiency Syndrome.

BACKGROUND: Immunodeficiency in acute ischemic stroke (AIS) is thought to be a result of norepinephrine suppression of the lymphoid tissue. The possible differences in the distribution of lymphocytes after stroke may be due to differences in responsiveness of lymphocyte ß-adrenergic receptors to their kinase (BARK-1). OBJECTIVE: The objective was to quantify the influence of lymphocyte BARK-1 on stroke-induced immunodeficiency in AIS patients. METHODS: A prospective clinical cohort study was conducted (N = 44). Measures included age, gender, race, risk factors for stroke, stroke severity, comorbidities, presence of infection, white blood cell counts and differential proportions, and lymphocyte BARK-1. Student t tests, effect sizes, and linear and logistic regressions were conducted to test the study objective. The study was approved by the Oregon Health & Science University Institutional Review Board. RESULTS: There were significant changes in all white blood cells and differential proportions and in the National Institutes of Health Stroke Scale from admission to 48 hours after onset of stroke deficits. Higher BARK-1 influenced the lower lymphocyte proportion at 48 hours, independent of age, P < .0001. Furthermore, BARK-1 also was associated with an increase in the likelihood of having sustained or stroke-induced immunodeficiency at 48 hours: odds ratio, 2.41; 95% confidence interval, 1.10-5.25; P = .027, and odds ratio, 2.79; 95% confidence interval, 1.03-7.52; P = .043, respectively. In all backward stepwise selection of factors, BARK-1 was the only factor consistently retained in the models. CONCLUSIONS: ß-Adrenergic receptor kinase-1 has a significant quantifiable influence on lymphocyte proportion at 48 hours and on the classification of sustained stroke-induced immunodeficiency. CLINICAL IMPLICATIONS: ß-Adrenergic stimulation influences immunodeficiency in AIS.

Endovascular therapy after intravenous t-PA versus t-PA alone for stroke.

BACKGROUND: Endovascular therapy is increasingly used after the administration of intravenous tissue plasminogen activator (t-PA) for patients with moderate-to-severe acute ischemic stroke, but whether a combined approach is more effective than intravenous t-PA alone is uncertain. METHODS: We randomly assigned eligible patients who had received intravenous t-PA within 3 hours after symptom onset to receive additional endovascular therapy or intravenous t-PA alone, in a 2:1 ratio. The primary outcome measure was a modified Rankin scale score of 2 or less (indicating functional independence) at 90 days (scores range from 0 to 6, with higher scores indicating greater disability). RESULTS: The study was stopped early because of futility after 656 participants had undergone randomization (434 patients to endovascular therapy and 222 to intravenous t-PA alone). The proportion of participants with a modified Rankin score of 2 or less at 90 days did not differ significantly according to treatment (40.8% with endovascular therapy and 38.7% with intravenous t-PA; absolute adjusted difference, 1.5 percentage points; 95% confidence interval [CI], -6.1 to 9.1, with adjustment for the National Institutes of Health Stroke Scale [NIHSS] score [8-19, indicating moderately severe stroke, or ≥20, indicating severe stroke]), nor were there significant differences for the predefined subgroups of patients with an NIHSS score of 20 or higher (6.8 percentage points; 95% CI, -4.4 to 18.1) and those with a score of 19 or lower (-1.0 percentage point; 95% CI, -10.8 to 8.8). Findings in the endovascular-therapy and intravenous t-PA groups were similar for mortality at 90 days (19.1% and 21.6%, respectively; P=0.52) and the proportion of patients with symptomatic intracerebral hemorrhage within 30 hours after initiation of t-PA (6.2% and 5.9%, respectively; P=0.83). CONCLUSIONS: The trial showed similar safety outcomes and no significant difference in functional independence with endovascular therapy after intravenous t-PA, as compared with intravenous t-PA alone. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00359424.).

Characteristics of participants consenting versus declining follow-up for up to 10 years in a randomized clinical trial.

BACKGROUND: With patients living a decade or longer post-procedure, long-term data are needed to assess the durability of carotid artery stenting versus carotid endarterectomy. Identifying characteristics of those consenting or declining to continue in long-term follow-up may suggest strategies to improve retention in clinical trials. PURPOSE: This report describes differences between patients choosing or declining to continue follow-up for up to 10 years in the Carotid Revascularization Endarterectomy versus Stenting Trial. METHODS: Following completion of the primary outcome, patients who were in active Carotid Revascularization Endarterectomy versus Stenting Trial follow-up were asked to continue beyond their original 4-year commitment for a maximum of 10 years. The characteristics of those who consented were compared with those who declined. Univariate and multivariable logistic regression were used for analysis, and backwards stepwise logistic regression (the most parsimonious model) was used to determine the factors associated with continuation. RESULTS: Of the 1921 active Carotid Revascularization Endarterectomy versus Stenting Trial participants for whom consent to extend follow-up was requested, 1695 (88%; mean age: 68.4) consented; 226 (12%; mean age: 69.6) declined. Of those who did not consent versus those who consented, 66% versus 48% were symptomatic at baseline (p<0.0001), at follow-up 28% versus 20% were smokers (p=0.009), 85% versus 90% were hypertensive (p=0.01), and 84% versus 94% were dyslipidemic (p<0.0001). Additional factors that differed between those who did not consent and those who consented included the mean number of years in the study at time of consent (4.8 years vs 3.7 years (p=<0.0001)) and patients from sites that enrolled <30 patients compared to sites randomizing 30 or more (70% vs 52% (p<0.0001)). Multivariable logistic regression indicated that those with lesser odds of consenting to the extended follow-up were older (odds ratio: 0.80; 95% confidence interval: 0.67, 0.96), more likely to be symptomatic (odds ratio: 0.58; 95% confidence interval: 0.42, 0.80), smokers (odds ratio: 0.48; 95% confidence interval: 0.34, 0.70), were in the study 5+ years versus <3 (odds ratio: 0.21; 95% confidence interval: 0.13, 0.34), and at a site that randomized <30 patients (odds ratio: 0.46; 95% confidence interval: 0.33, 0.63), while patients with dyslipidemia at follow-up had increased odds of consenting (odds ratio: 2.28 (1.47, 3.54)). CONCLUSION: Symptomatic status, increasing age, randomized at lower volume centers, and longer time in follow-up were associated with reduced odds of consenting to long-term follow-up. Identifying factors associated with reduced willingness to extend participation long-term can suggest targeted strategies to improve retention in future clinical trials.

Association of intraprocedural blood pressure and end tidal carbon dioxide with outcome after acute stroke intervention.

BACKGROUND: General anesthesia (GA) for acute stroke interventions may be associated with inferior functional outcomes. Our goal was to identify physiologic parameters that mediate this association. METHODS: Consecutive patients treated at our institution between August 2007 and December 2010 were identified from a prospective database. Clinical data were then extracted by retrospective chart review. Variables significantly associated with outcome in univariate analysis were also examined in multivariate analysis, controlling for well-established prespecified predictors of functional outcome. RESULTS: Of the 106 patients identified, 20 were excluded (17 due to the absence of 90-day mRS and 3 due to insufficient anesthetic records). Blood pressure (BP) decreased significantly after induction of GA, but there was no association between BP and outcome. End tidal carbon dioxide values (ETCO2) at 60 and 90 min, however, were significantly associated with outcomes in both univariate and multivariate analyses. Mean ETCO2 in patients with favorable outcomes (modified Rankin Scale (mRS) 0-3) was higher than in those with unfavorable outcomes (mRS 4-6): 35.2 mmHg versus 32.2 (p = 0.03) at 60 min and 34.9 versus 31.9 (p = 0.04) at 90 min. The adjusted odds ratios for poor outcomes for each 1 mmHg decrease in ETCO2 were the same: 0.76 (95 % CI 0.65-0.92; p = 0.004) at 60 min and 0.76 (95 % CI 0.61-0.93; p = 0.01) at 90 min. CONCLUSIONS: While BP decreased significantly in patients undergoing GA for acute stroke intervention, it did not correlate with patient outcome. Decreases in ETCO2 at 30 and 60 min, however, were associated with 90-day mRS.

Stroke after carotid stenting and endarterectomy in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST).

BACKGROUND: Stroke occurs more commonly after carotid artery stenting than after carotid endarterectomy. Details regarding stroke type, severity, and characteristics have not been reported previously. We describe the strokes that have occurred in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST). METHODS AND RESULTS: CREST is a randomized, open-allocation, controlled trial with blinded end-point adjudication. Stroke was a component of the primary composite outcome. Patients who received their assigned treatment within 30 days of randomization were included. Stroke was adjudicated by a panel of board-certified vascular neurologists with secondary central review of clinically obtained brain images. Stroke type, laterality, timing, and outcome were reported. A periprocedural stroke occurred among 81 of the 2502 patients randomized and among 69 of the 2272 in the present analysis. Strokes were predominantly minor (81%, n=56), ischemic (90%, n=62), in the anterior circulation (94%, n=65), and ipsilateral to the treated artery (88%, n=61). There were 7 hemorrhages, which occurred 3 to 21 days after the procedure, and 5 were fatal. Major stroke occurred in 13 (0.6%) of the 2272 patients. The estimated 4-year mortality after stroke was 21.1% compared with 11.6% for those without stroke. The adjusted risk of death at 4 years was higher after periprocedural stroke (hazard ratio, 2.78; 95% confidence interval, 1.63-4.76). CONCLUSIONS: Stroke, particularly severe stroke, was uncommon after carotid intervention in CREST, but stroke was associated with significant morbidity and was independently associated with a nearly 3-fold increased future mortality. The delayed timing of major and hemorrhagic stroke after revascularization suggests that these strokes may be preventable.

Stenting versus endarterectomy for treatment of carotid-artery stenosis.

BACKGROUND: Carotid-artery stenting and carotid endarterectomy are both options for treating carotid-artery stenosis, an important cause of stroke. METHODS: We randomly assigned patients with symptomatic or asymptomatic carotid stenosis to undergo carotid-artery stenting or carotid endarterectomy. The primary composite end point was stroke, myocardial infarction, or death from any cause during the periprocedural period or any ipsilateral stroke within 4 years after randomization. RESULTS: For 2502 patients over a median follow-up period of 2.5 years, there was no significant difference in the estimated 4-year rates of the primary end point between the stenting group and the endarterectomy group (7.2% and 6.8%, respectively; hazard ratio with stenting, 1.11; 95% confidence interval, 0.81 to 1.51; P=0.51). There was no differential treatment effect with regard to the primary end point according to symptomatic status (P=0.84) or sex (P=0.34). The 4-year rate of stroke or death was 6.4% with stenting and 4.7% with endarterectomy (hazard ratio, 1.50; P=0.03); the rates among symptomatic patients were 8.0% and 6.4% (hazard ratio, 1.37; P=0.14), and the rates among asymptomatic patients were 4.5% and 2.7% (hazard ratio, 1.86; P=0.07), respectively. Periprocedural rates of individual components of the end points differed between the stenting group and the endarterectomy group: for death (0.7% vs. 0.3%, P=0.18), for stroke (4.1% vs. 2.3%, P=0.01), and for myocardial infarction (1.1% vs. 2.3%, P=0.03). After this period, the incidences of ipsilateral stroke with stenting and with endarterectomy were similarly low (2.0% and 2.4%, respectively; P=0.85). CONCLUSIONS: Among patients with symptomatic or asymptomatic carotid stenosis, the risk of the composite primary outcome of stroke, myocardial infarction, or death did not differ significantly in the group undergoing carotid-artery stenting and the group undergoing carotid endarterectomy. During the periprocedural period, there was a higher risk of stroke with stenting and a higher risk of myocardial infarction with endarterectomy. (ClinicalTrials.gov number, NCT00004732.)

Differential effect of gold nanoparticles on cerebrovascular function and biomechanical properties.

Human stroke serum (HSS) has been shown to impair cerebrovascular function, likely by factors released into the circulation after ischemia. 20 nm gold nanoparticles (GNPs) have demonstrated anti-inflammatory properties, with evidence that they decrease pathologic markers of ischemic severity. Whether GNPs affect cerebrovascular function, and potentially protect against the damaging effects of HSS on the cerebral circulation remains unclear. HSS obtained 24 h poststroke was perfused through the lumen of isolated and pressurized third-order posterior cerebral arteries (PCAs) from male Wistar rats with and without GNPs (~2 × 109 GNP/ml), or GNPs in vehicle, in an arteriograph chamber (n = 8/group). All vessels were myogenically reactive ≥60 mmHg intravascular pressure; however, vessels containing GNPs had significantly less myogenic tone. GNPs increased vasoreactivity to small and intermediate conductance calcium activated potassium channel activation via NS309; however, reduced vasoconstriction to nitric oxide synthase inhibition. Hydraulic conductivity and transvascular filtration, were decreased by GNPs, suggesting a protective effect on the blood-brain barrier. The stress-strain curves of PCAs exposed to GNPs were shifted leftward, indicating increased vessel stiffness. This study provides the first evidence that GNPs affect the structure and function of the cerebrovasculature, which may be important for their development and use in biomedical applications.

Costs and cost-effectiveness of carotid stenting versus endarterectomy for patients at standard surgical risk: results from the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST).

BACKGROUND AND PURPOSE: The Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) demonstrated similar rates of the primary composite end point between carotid artery stenting (CAS) and carotid endarterectomy (CEA), although the risk of stroke was higher with CAS, and the risk of myocardial infarction was higher with CEA. Given the large number of patients who are candidates for these procedures, an understanding of their relative cost and cost-effectiveness may have important implications for health care policy and treatment guidelines. METHODS: We performed a formal economic evaluation alongside the CREST trial. Costs were estimated from all trial participants over the first year of follow-up using a combination of resource use data and hospital billing data. Patient-level health use scores were obtained using data from the SF-36. We then used a Markov disease-simulation model calibrated to the CREST results to project 10-year costs and quality-adjusted life expectancy for the 2 treatment groups. RESULTS: Although initial procedural costs were $1025/patient higher with CAS, postprocedure costs and physician costs were lower such that total costs for the index hospitalization were similar for the CAS and CEA groups ($15 055 versus $14 816; mean difference, $239/patient; 95% CI for difference, -$297 to $775). Neither follow-up costs after discharge nor total 1-year costs differed significantly. For the CREST population, model-based projections over a 10-year time horizon demonstrated that CAS would result in a mean incremental cost of $524/patient and a reduction in quality-adjusted life expectancy of 0.008 years compared with CEA. Probabilistic sensitivity analysis demonstrated that CEA was economically attractive at an incremental cost-effectiveness threshold of $50 000/quality-adjusted life-year gained in 54% of samples, whereas CAS was economically attractive in 46%. CONCLUSIONS: Despite slightly lower in-trial costs and lower rates of stroke with CEA compared with CAS, projected 10-year outcomes from this controlled clinical trial demonstrate only trivial differences in overall healthcare costs and quality-adjusted life expectancy between the 2 strategies. If the CREST results can be replicated in clinical practice, these findings suggest that factors other than cost-effectiveness should be considered when deciding between treatment options for carotid artery stenosis in patients at standard risk for surgical complications. Clinical Trial Registration- URL: http://clinicaltrials.gov. Unique Identifier: NCT00004732.

Matrix metalloproteinase-9 in an exploratory trial of intravenous minocycline for acute ischemic stroke.

BACKGROUND AND PURPOSE: Plasma matrix metalloproteinase-9 levels predict posttissue plasminogen activator (tPA) hemorrhage. METHODS: The authors investigated the effect of minocycline on plasma matrix metalloproteinase-9 in acute ischemic stroke in the Minocycline to Improve Neurological Outcome in Stroke (MINOS) trial and a comparison group. RESULTS: Matrix metalloproteinase-9 level decreased at 72 hours compared with baseline in MINOS (tPA, P=0.0022; non-tPA, P=0.0066) and was lower than in the non-MINOS comparison group at 24 hours (tPA, P<0.0001; non-tPA, P=0.0019). CONCLUSIONS: Lower plasma matrix metalloproteinase-9 was seen among tPA-treated subjects in the MINOS trial. Combining minocycline with tPA may prevent the adverse consequences of thrombolytic therapy through suppression of matrix metalloproteinase-9 activity.

Safety of stenting and endarterectomy by symptomatic status in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST).

BACKGROUND AND PURPOSE: The safety of carotid artery stenting (CAS) and carotid endarterectomy (CEA) has varied by symptomatic status in previous trials. The Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST) data were analyzed to determine safety in symptomatic and asymptomatic patients. METHODS: CREST is a randomized trial comparing safety and efficacy of CAS versus CEA in patients with high-grade carotid stenoses. Patients were defined as symptomatic if they had relevant symptoms within 180 days of randomization. The primary end point was stroke, myocardial infarction, or death within the periprocedural period or ipsilateral stroke up to 4 years. RESULTS: For 1321 symptomatic and 1181 asymptomatic patients, the periprocedural aggregate of stroke, myocardial infarction, and death did not differ between CAS and CEA (5.2% versus 4.5%; hazard ratio, 1.18; 95% CI, 0.82 to 1.68; P=0.38). The stroke and death rate was higher for CAS versus CEA (4.4% versus 2.3%; hazard ratio, 1.90; 95% CI, 1.21 to 2.98; P=0.005). For symptomatic patients, the periprocedural stroke and death rates were 6.0%±0.9% for CAS and 3.2%±0.7% for CEA (hazard ratio, 1.89; 95% CI, 1.11 to 3.21; P=0.02). For asymptomatic patients, the stroke and death rates were 2.5%±0.6% for CAS and 1.4%±0.5% for CEA (hazard ratio, 1.88; 95% CI, 0.79 to 4.42; P=0.15). Rates were lower for those aged <80 years. CONCLUSIONS: There were no significant differences between CAS versus CEA by symptomatic status for the primary CREST end point. Periprocedural stroke and death rates were significantly lower for CEA in symptomatic patients. However, for both CAS and CEA, stroke and death rates were below or comparable to those of previous randomized trials and were within the complication thresholds suggested in current guidelines for both symptomatic and asymptomatic patients.

Potentiating intra-arterial sonothrombolysis for acute ischemic stroke by the addition of the ultrasound contrast agents (Optison™ & SonoVue(®)).

Transcranial ultrasound in combination with intravenously administered ultrasound contrast agents (UCA) in the presence or absence of recombinant tissue plasminogen activator (rt-PA) has been widely evaluated as a new modality for treatment of ischemic stroke. Despite the successful demonstration of accelerated clot lysis there are inherent limitations associated with this modality such as inconsistency in temporal window thickness and/or potential serious cardiopulmonary reactions to intravenous administration of UCA that prevent broad application to ischemic stroke populations. As a complementary modality, we evaluated potential lysis enhancement by intra-arterial ultrasound with concurrent intra-clot delivery of UCA and rt-PA. To this end, clots were formed with average pore diameter similar to clinically retracted clots by adjusting the thrombin concentration. Physical characteristic and retention of UCA after delivery through the catheter as a function of clinically relevant flow rates of 6, 12, 18 ml/h were determined using a microscopic method. The ability of the UCA employed in this study, Optison and SonoVue, to penetrate into the clot was verified using ultrasound B-mode imaging. Clot lysis as a function of rt-PA concentration, 0.009 through 0.5 mg/ml, in the presence and absence of UCA diluted to 1:10, 1:100, and 1:200 v/v at two Peak rarefaction acoustic pressures of 1.3 and 2.1 MPa were evaluated using a weighing method. The study results suggest the addition of only 0.02 ml of 1:100 diluted UCA to rt-PA of 0.009, 0.05, 0.3, and 0.5 mg/ml can enhance the lysis rate by 3.9, 2.6, 1.9 and 1.8 fold in the presence of peak rarefaction acoustic pressure of 1.3 MPa and by 5.1, 3.4, 2.6, 3.1 in the presence of peak rarefaction acoustic pressure of 2.1 MPa, respectively. In addition, Optison and SonoVue demonstrated comparable effectiveness in enhancing the clot lysis rate. Addition of UCA to intra-arterial sonothrombolysis could be considered as a viable treatment option for ischemic stroke patients.

Minocycline to improve neurologic outcome in stroke (MINOS): a dose-finding study.

BACKGROUND AND PURPOSE: Minocycline is a promising anti-inflammatory and protease inhibitor that is effective in multiple preclinical stroke models. We conducted an early phase trial of intravenous minocycline in acute ischemic stroke. METHODS: Following an open-label, dose-escalation design, minocycline was administered intravenously within 6 hours of stroke symptom onset in preset dose tiers of 3, 4.5, 6, or 10 mg/kg daily over 72 hours. Minocycline concentrations for pharmacokinetic analysis were measured in a subset of patients. Subjects were followed for 90 days. RESULTS: Sixty patients were enrolled, 41 at the highest dose tier of 10 mg/kg. Overall age (65±13.7 years), race (83% white), and sex (47% female) were consistent across the doses. The mean baseline National Institutes of Health Stroke Scale score was 8.5±5.8 and 60% received tissue plasminogen activator. Minocycline infusion was well tolerated with only 1 dose limiting toxicity at the 10-mg/kg dose. No severe hemorrhages occurred in tissue plasminogen activator-treated patients. Pharmacokinetic analysis (n=22) revealed a half-life of approximately 24 hours and linearity of parameters over doses. CONCLUSIONS: Minocycline is safe and well tolerated up to doses of 10 mg/kg intravenously alone and in combination with tissue plasminogen activator. The half-life of minocycline is approximately 24 hours, allowing every 24-hour dosing. Minocycline may be an ideal agent to use with tissue plasminogen activator.

Indications and applications of arterial stents for stroke prevention in atherosclerotic intracranial stenosis.

Intracranial stenosis accounts for 8-10% of all ischemic strokes in North America, a frequency slightly less than that of extracranial carotid stenosis. Among patients presenting with transient ischemic attack or stroke due to intracranial stenosis, the risk of recurrent stroke in the first year after initial symptoms is about 14%. Those with high-risk features (recent stroke and severe stenosis) have up to a 23% rate of recurrent stroke in the year after their initial event. Angioplasty with stenting has emerged as a potential treatment strategy, particularly in high-risk patients, although evidence is currently limited to uncontrolled prospective trials and retrospective case series. In this article, we critically review the clinical results supporting the use of stenting and highlight some key considerations in the application of this technology, including patient selection, procedural management, technical issues, and risk factors for complications and in-stent restenosis.