Subsequent Ipsilateral Stroke Research Articles

Qualifying Event and Recurrence of Ischemic Stroke in Symptomatic Artery Occlusion: A Post Hoc Analysis of CMOSS.

The authors aimed to elucidate the relationship between latest ischemic event and the incidence of subsequent ischemic stroke in patients with symptomatic artery occlusion. We analyzed the association between qualifying event-the latest ischemic event (transient ischemic attack [TIA] or stroke)-and the incidence of ipsilateral ischemic stroke in patients with symptomatic artery occlusion treated with medical therapy alone in CMOSS (Carotid or Middle Cerebral Artery Occlusion Surgery Study). The incidence of CMOSS primary outcomes, including any stroke or death within 30 days after randomization or ipsilateral ischemic stroke between 30 days and 2 years, between the bypass surgical and medical groups, stratified by qualifying events, was also compared. Of the 165 patients treated with medical therapy alone, 75 had a TIA and 90 had a stroke as their qualifying event. The incidence of ipsilateral ischemic stroke did not significantly differ between patients with a TIA and those with a stroke as their qualifying event (13.3% versus 6.7%, P=0.17). In multivariate analysis, the qualifying event was not associated with the incidence of ipsilateral ischemic stroke. There were no significant differences in the CMOSS primary outcomes between the surgical and medical groups, regardless of the qualifying event being TIA (10.1% versus 12.2%, P=0.86) or stroke (6.7% versus 8.9%, P=0.55). Among patients with symptomatic artery occlusion and hemodynamic insufficiency, the risk of subsequent ipsilateral ischemic stroke does not appear to be lower in patients presenting with a TIA compared with those with a stroke. URL: https://www.clinicaltrials.gov; Unique identifier: NCT01758614.

Carotid Plaque Characterization Using Dual‐Energy Computed Tomography: Predicting Imminent Ipsilateral Ischemic Stroke in 30 Days

Background Despite progress in noninvasive means for visualizing and characterizing carotid plaque morphology, current clinical practice and AHA/ASA guidelines do not employ any plaque characteristics in deciding whether a patient should undergo carotid endarterectomy. Our objective is to evaluate the utility of dual‐energy computed tomography imaging characteristics of the carotid plaques to differentiate between the stable and unstable plaques and to predict subsequent ipsilateral ischemic stroke within 30 days. Methods In this retrospective case‐controlled study, 1185 consecutive neck computed tomography angiograms from November 2017 to October 2019 were included. In this cohort, 14 patients who experienced acute ischemic strokes caused by carotid plaque rupture within 30 days were identified and analyzed. Forty‐two patients who did not suffer an ischemic stroke but had matched risk factors were selected as control. Univariable and multivariate logistic regressions were used to develop a predictive model. Through a similar retrospective review of 483 stroke patients from November 2019 to October 2020, an independent test data set of 60 patients (15:45) was identified and used to assess the predictive performance of the model. Results In the univariable models, the plaque thickness (odds ratio [OR],1.59; 95% CI, 1.12–2.24; P =0.009), degree of stenosis (OR, 1.05; 95% CI, 1.02–1.09; P =0.002), plaque ulceration (OR, 20.00; 95% CI, 3.42–116.80; P =0.001), and intraplaque hemorrhage (OR, 7.22; 95% CI, 1.45–35.93; P =0.016) showed significant association with a subsequent stroke. Patent luminal diameter (OR, 0.62; 95% CI, 0.45–0.85; P =0.003) and maximal external diameter (OR, 0.70; 95% CI, 0.50–0.99; P =0.046) were inversely associated with a subsequent stroke. The final predictive model derived from multiple logistic regression included patent luminal diameter, maximal external diameter, degree of stenosis, plaque ulceration, and intraplaque hemorrhage. On the independent test data set, the model showed high specificity (84%) and negative predictive value (90%) with moderate sensitivity (73%) and positive predictive value (61%). The overall accuracy was 82%. Conclusions Dual‐energy computed tomography imaging features of carotid plaque may aid in prediction of a subsequent ipsilateral ischemic stroke within 30 days following the imaging study. Such information may guide the clinical management of vulnerable plaque.

Abstract 1122‐000227: Stenting Versus Medical Treatment for Chronic Internal Carotid Artery Occlusions: A Systematic Review and Meta‐analysis

Introduction : Chronic internal carotid occlusion is responsible for 10–15% ischemic strokes or transit ischemic attacks (TIA). Subsequent ipsilateral ischemic stroke rate is 5.9% per year. However, this risk can increase up to 23% in two years in a subgroup of patients with poor collaterals regardless of medical therapy with antiplatelet or anticoagulant agents. Prevention of subsequent stroke in patients with carotid artery occlusion remains a difficult challenge. Carotid artery stenting (CAS) has recently been considered in its management. However, there is ambiguity on its safety. We aim to evaluate the safety and feasibility of CAS and compared it with medical management. Methods : We performed a systematic review and meta‐analysis to compare long‐term outcome (stroke recurrence) of current carotid occlusion treatments (CAS vs medical therapy). Two independent reviewers performed the screening, data extraction, and quality assessment. A random effects model was used for analysis. Results : A total of 5720 studies were screened. Of these, 11 studies were included in our systematic review and meta‐analysis of proportions. The CAS group has lower proportions of recurrent strokes (5% vs 30%,) after 30 days than medical therapy alone. Additionally, the proportion of periprocedural intracranial hemorrhage was 4.4% (95% CI 2.5 to 6.8) in the CAS group. Conclusions : CAS of the chronically occluded cervical ICA seems to be a safe procedure with lower rates of recurrent stroke in clinical follow up. Future randomized studies are warranted to guide the optimal management of this complex disease.

Long-term outcomes of stenting and endarterectomy for symptomatic carotid stenosis: a preplanned pooled analysis of individual patient data

The risk of periprocedural stroke or death is higher after carotid artery stenting (CAS) than carotid endarterectomy (CEA) for the treatment of symptomatic carotid stenosis. However, long-term outcomes have not been sufficiently assessed. We sought to combine individual patient-level data from the four major randomised controlled trials of CAS versus CEA for the treatment of symptomatic carotid stenosis to assess long-term outcomes. We did a pooled analysis of individual patient-level data, acquired from the four largest randomised controlled trials assessing the relative efficacy of CAS and CEA for treatment of symptomatic carotid stenosis (Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy trial, International Carotid Stenting Study, and Carotid Revascularization Endarterectomy versus Stenting Trial). The risk of ipsilateral stroke was assessed between 121 days and 1, 3, 5, 7, 9, and 10 years after randomisation. The primary outcome was the composite risk of stroke or death within 120 days after randomisation (periprocedural risk) or subsequent ipsilateral stroke up to 10 years after randomisation (postprocedural risk). Analyses were intention-to-treat, with the risk of events calculated using Kaplan-Meier methods and Cox proportional hazards analysis with adjustment for trial. In the four trials included, 4775 patients were randomly assigned, of whom a total of 4754 (99·6%) patients were followed up for a maximum of 12·4 years. 21 (0·4%) patients immediately withdrew consent after randomisation and were excluded. Median length of follow-up across the studies ranged from 2·0 to 6·9 years. 129 periprocedural and 55 postprocedural outcome events occurred in patients allocated CEA, and 206 and 57 for those allocated CAS. After the periprocedural period, the annual rates of ipsilateral stroke per person-year were similar for the two treatments: 0·60% (95% CI 0·46-0·79) for CEA and 0·64% (0·49-0·83) for CAS. Nonetheless, the periprocedural and postprocedural risks combined favoured CEA, with treatment differences at 1, 3, 5, 7, and 9 years all ranging between 2·8% (1·1-4·4) and 4·1% (2·0-6·3). Outcomes in the postprocedural period after CAS and CEA were similar, suggesting robust clinical durability for both treatments. Although long-term outcomes (periprocedural and postprocedural risks combined) continue to favour CEA, the similarity of the postprocedural rates suggest that improvements in the periprocedural safety of CAS could provide similar outcomes of the two procedures in the future. None.

Abstract TMP34: The Challenge and Yield of Racially and Ethnically Diverse Patient Populations in Low Event-Rate Clinical Trials

Background: Concern for underrepresentation of minorities in clinical trials has focused on enrollment proportions and generalizability. The interplay of trial event-rates with diversity has not been emphasized. Methods: The Carotid Revascularization Endarterectomy vs Stent Trial (CREST) randomized 2502 patients and compared them by race, ethnicity, baseline characteristics, and primary outcome (any peri-procedural stroke, death or MI and subsequent ipsilateral stroke up to 10 years); those with unknown race or ethnicity were excluded. Proportional hazards models adjusting for age, sex, symptomatic status and treatment were used to test for a treatment by race/ethnicity interaction. Results: One-hundred-nine patients (4.4%) were black, 32 (1.3%) Asian, 2332 (93.4%) white, 11 (0.4%) other by self-report, and 18 (0.7%) unknown; 90 (3.6%) were Hispanic, 2377 (95%) non-Hispanic, and 35 (1.4%) unknown. Compared to whites, racial minorities were younger (mean age 67±8.9 vs 69±8.8, p=0.004), more often female (44% vs 34%, p=0.01), symptomatic (63 vs 52%, p=0.01), and diabetic (51% vs 29%, p<0.0001), but less often dyslipidemic (76% vs 85%, p=0.004), current smokers (19% vs 27%, p=0.04), or had a history of cardiovascular disease (34% vs 46%, p=0.007). Hispanics were more often diabetic (48% vs 30%, p=0.0002). The rate of the primary endpoint was 10.9%±0.9% at 10 years, and did not differ by race or ethnicity (p inter >0.24). In the context of this low rate, even if minority recruitment were increased to represent 50% of study participants, and if the treatment difference in one race were a greater hazard of HR = 1.49 (anticipated alternative hypothesis), then the hazard ratio in the other group would need to be <0.73, or >3.31, to have 90% power of detection. Conclusions: The proportion of racial and ethnicity participation in CREST was suboptimal at < 10%. Primary outcomes did not differ by minority or ethnic status. However, in low event-rate trials very high and even unrealistic enrollment goals for diversity, for example ≥50%, may still be insufficient for detection of outcome differences by race or ethnicity.

The Carotid and Middle cerebral artery Occlusion Surgery Study (CMOSS): a study protocol for a randomised controlled trial.

BackgroundPatients with symptomatic internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion with haemodynamic insufficiency are at high risk for recurrent stroke when treated medically.MethodsThe Carotid or Middle cerebral artery Occlusion Surgery Study (CMOSS) trial is an ongoing, government-funded, prospective, multicentre, randomised controlled trial. The CMOSS will recruit 330 patients with symptomatic ICA or MCA occlusion (parallel design, 1:1 allocation ratio) and haemodynamic insufficiency. Participants will be allocated to best medical treatment alone or best medicine plus extracranial-intracranial (EC-IC) bypass surgery. The primary outcome events are all strokes or deaths occurring between randomisation and 30 days post operation or post randomisation and ipsilateral ischaemic stroke within 2 years. Recruitment will be finished by December 2016. All the patients will be followed for at least 2 years. The trial is scheduled to complete in 2019.DiscussionThe CMOSS will test the hypothesis that EC-IC bypass surgery plus best medical therapy reduces subsequent ipsilateral ischaemic stroke in patients with symptomatic ICA or MCA occlusion and haemodynamic cerebral ischaemia. This manuscript outlines the rationale and the design of the study. CMOSS will allow for more critical reappraisal of the EC-IC bypass for selected patients in China.Trial registration NCT01758614 with ClinicalTrials.gov. Registered on 24 December 2012.

Long-Term Results of Stenting Versus Endarterectomy for Carotid-Artery Stenosis

With 10 years of follow-up, there was no significant difference in patients who underwent carotid artery stenting or carotid endarterectomy (CEA) with respect to the combined outcome of periprocedural stroke, myocardial infarction, death and subsequent ipsilateral stroke. Rates of postprocedural ipsilateral stroke did not differ between groups.

Safety and Efficacy of Wingspan Stenting for Severe Symptomatic Atherosclerotic Stenosis of the Middle Cerebral Artery: Analysis of 278 Continuous Cases

Our objective is to investigate the safety and long-term efficacy of the Wingspan stent (Boston Scientific, Natick, MA, USA) for treating severe atherosclerotic stenosis of the middle cerebral artery (MCA). A total of 278 consecutive patients from our stroke database with clinical symptoms within the prior 90 days and intracranial atherosclerotic stenosis of 70% or above of the MCA were enrolled in this study between September 2012 and November 2014, and these patients were followed until the end of June 2015. The endpoint events included any stroke or death within 30 days after stenting and any subsequent ipsilateral ischemic stroke. Among the 278 enrolled patients, 277 patients (99.6%) successfully underwent stenting. The mean rate of stenosis decreased from 82.5 ± 7.9% to 9.0 ± 3.2% following treatment. Within 30 days after stenting, 12 patients (4.3%) experienced endpoint events, including 8 cases (2.9%) of hemorrhagic stroke and 4 cases (1.4%) of ischemic stroke; 2 perioperative deaths occurred. During 8-33 months of follow-up, 19 patients developed endpoint events. The 1- and 2-year endpoint event rates were 5.8% (95% confidence interval [CI], 5.0%-15.7%) and 7.2% (95% CI, 4.3%-10.1%), respectively. From this study, we can conclude that the treatment of severe symptomatic atherosclerotic stenosis of the MCA using the Wingspan stent was safe and effective and that the long-term stroke recurrence rate after stenting was low.

Relative Mean Transit Time Predicts Subsequent Stroke in Symptomatic Carotid Occlusion

Mean transit time (MTT) measurements to assess cerebral hemodynamics are easily obtained by computed tomography and magnetic resonance imaging. We reviewed hemodynamic and clinical outcome data from the St. Louis Carotid Occlusion Study to determine if increased MTT was associated with an increased risk of stroke in patients with symptomatic complete carotid artery occlusion. Positron emission tomography (PET) studies of cerebral blood volume-to-cerebral blood flow ratios were used to calculate MTTs. Mean ipsilateral (side of the occluded internal carotid artery)-to-contralateral ratios of MTTs in the middle cerebral artery territories were determined. MTT was tested as a predictor of stroke risk using Cox regression analysis. Receiver operating characteristic curves for stroke risk prediction were generated by varying the mean ispilateral-to-contralateral MTT ratio to identify an optimal cutpoint. Increased MTT ratio was associated with an increased risk of ipsilateral stroke (P < .001). The maximum combination of sensitivity (.778) and specificity (.763) was obtained at a cutpoint ratio of 1.387 or higher. Subjects with a MTT ratio of 1.387 or higher had a 29.3% 2-year risk of ipsilateral stroke compared to 4.6% for those without (P < .001). PET relative MTT ratio identified patients with symptomatic complete internal artery occlusion who were at high risk for subsequent ipsilateral stroke. Confirmation using measurements of relative MTT from other imaging modalities in a patient cohort receiving contemporary medical management is needed.

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

BackgroundIn 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.MethodsAmong 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.ResultsAmong 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.ConclusionsOver 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.)

Abstract 134: Relative MTT Predicts Subsequent Stroke in Symptomatic Carotid Occlusion

Relative mean transit time (MTT) is readily obtainable from dynamic susceptibility contrast MRI of the brain. While it has received much attention in acute ischemic stroke as a possible means to identify patients for reperfusion therapies, little has been done to determine if it has clinical significance outside the acute setting. To determine if relative MTT could be used to identify patients who are at high risk for subsequent stroke, we analyzed data from the St. Louis Carotid Occlusion Study. This prospective study was carried out from 1992-1997 to determine if PET measurement of oxygen extraction fraction could identify medically treated patients with recently symptomatic carotid artery occlusion at high risk for subsequent stroke. Sixty-eight of the participants in the study had quantitative PET measurements of cerebral blood flow (CBF) and cerebral blood volume (CBV). From these we calculated the MTT (CBV/CBF) in each middle cerebral artery territory and determined the MTT ratio of the ipsilateral to the contralateral hemisphere (I/C MTT ratio). Nine of the 68 participants had a subsequent ipsilateral ischemic stroke during mean follow-up of 2.6 years (range .5 - 5 years). The I/C MTT ratio was significantly associated with subsequent stroke as a continuous variable by Cox regression analysis (HR 65, 95%CI 7-613, p &lt; .001). The maximum combination of sensitivity (.778) and specificity (.763) was obtained with a cutpoint of ≥ 1.387 which identified 7/9 subsequent strokes (PPV .333, NPV .957). Relative MTT shows great promise as a means to identify patients with large artery disease who are at high risk for subsequent stoke. These results need to be confirmed using MRI in a cohort receiving contemporary medical management.

Lower stroke risk with lower blood pressure in hemodynamic cerebral ischemia

To determine whether strict blood pressure (BP) control is the best medical management for patients with symptomatic carotid artery occlusion and hemodynamic cerebral ischemia. In this prospective observational cohort study, we analyzed data from 91 participants in the nonsurgical group of the Carotid Occlusion Surgery Study (COSS) who had recent symptomatic internal carotid artery occlusion and hemodynamic cerebral ischemia manifested by ipsilateral increased oxygen extraction fraction. The target BP goal in COSS was ≤130/85 mm Hg. We compared the occurrence of ipsilateral ischemic stroke during follow-up in the 41 participants with mean BP ≤130/85 mm Hg to the remaining 50 with higher BP. Of 16 total ipsilateral ischemic strokes that occurred during follow-up, 3 occurred in the 41 participants with mean follow-up BP of ≤130/85 mm Hg, compared to 13 in the remaining 50 participants with mean follow-up BP >130/85 mm Hg (hazard ratio 3.742, 95% confidence interval 1.065-13.152, log-rank p = 0.027). BPs ≤130/85 mm Hg were associated with lower subsequent stroke risk in these patients. This study provides Class III evidence that control of hypertension ≤130/85 mm Hg is associated with a reduced risk of subsequent ipsilateral ischemic stroke in patients with recently symptomatic carotid occlusion and hemodynamic cerebral ischemia (increased oxygen extraction fraction).

Positron emission tomography of the vulnerable atherosclerotic plaque in man – a contemporary review

Atherosclerosis is the primary underlying cause of cardiovascular disease (CVD). It is the leading cause of morbidity and mortality in the Western world today and is set to become the prevailing disease and major cause of death worldwide by 2020. In the 1950s surgical intervention was introduced to treat symptomatic patients with high-grade carotid artery stenosis due to atherosclerosis – a procedure known as carotid endarterectomy (CEA). By removing the atherosclerotic plaque from the affected carotid artery of these patients, CEA is beneficial by preventing subsequent ipsilateral ischemic stroke. However, it is known that patients with low to intermediate artery stenosis may still experience ischemic events, leading clinicians to consider plaque composition as an important feature of atherosclerosis. Today molecular imaging can be used for characterization, visualization and quantification of cellular and subcellular physiological processes as they take place in vivo; using this technology we can obtain valuable information on atherosclerostic plaque composition. Applying molecular imaging clinically to atherosclerotic disease therefore has the potential to identify atherosclerotic plaques vulnerable to rupture. This could prove to be an important tool for the selection of patients for CEA surgery in a health system increasingly focused on individualized treatment. This review focuses on current advances and future developments of in vivo atherosclerosis PET imaging in man.

Emergency EC-IC bypass for symptomatic atherosclerotic ischemic stroke

Previous studies have shown that extracranial-intracranial (EC-IC) bypass surgery has no preventive effect on subsequent ipsilateral ischemic stroke in patients with symptomatic atherosclerotic internal carotid occlusion and hemodynamic cerebral ischemia. A few studies have assessed whether an urgent EC-IC bypass surgery is an effective treatment for main trunk stenosis or occlusion in acute stage. The authors retrospectively reviewed 58 consecutive patients who underwent urgent EC-IC bypass for symptomatic internal carotid artery or the middle cerebral artery stenosis or occlusion between January 2003 and December 2011. Clinical characteristics and neuroimagings were evaluated and analyzed. Based on preoperative angiogram, responsible lesions were the internal carotid artery in 19 (32.8%) patients and the middle cerebral artery in 39 (67.2%). No hemorrhagic complication occurred. Sixty-nine percent of patients showed improvement of neurological function after surgery, and 74.1% of patients had favorable outcome. Unfavorable outcome was associated with insufficient collateral flow and new infarction after bypass surgery.

Progression of Carotid Artery Stenosis Is Associated With the Occurrence of Subsequent Ipsilateral Ischemic Events and Stroke: Results From the ACSRS Study

Progression of Carotid Artery Stenosis Is Associated With the Occurrence of Subsequent Ipsilateral Ischemic Events and Stroke: Results From the ACSRS Study

Abstract 155: No Increased Stroke Risk with Lower Blood Pressures in Hemodynamic Cerebral Ischemia

Patients with symptomatic carotid artery occlusion and hemodynamic cerebral ischemia manifested by increased oxygen extraction fraction (OEF) are at 20-25% risk for ipsilateral stroke within 2 years. Disagreement exists whether strict blood pressure control is the best medical management for these patients or if higher blood pressures are needed to preserve cerebral perfusion. To address this issue, we analyzed data from the non-surgical group of the Carotid Occlusion Surgery Study (COSS), a randomized, controlled trial performed to determine whether EC-IC bypass could reduce subsequent ipsilateral ischemic stroke at two years in participants with recently symptomatic internal carotid artery occlusion and increased OEF. Of the 98 patients in the non-surgical group, 95 had 1-19 blood pressures recorded at follow-up visits. Average systolic and diastolic blood pressures were calculated from these data. Cox regression analyses were used to estimate the relative hazard of a post-randomization ipsilateral stroke in the tercile of subjects with the lowest average blood pressures ( &lt;/= 124 mm Hg systolic or 73 mm Hg diastolic) compared to the remainder. Lower blood pressures were associated with reduced, not increased, stroke risk. If the samples analyzed were from populations in which the true hazards were the same, hazard ratios of this magnitude or less would be expected less than 10% of the time. We cannot conclude from these data that strict blood pressure control is beneficial in patients with symptomatic carotid occlusion and increased OEF. However, since we found no evidence that that blood pressures below 124/73 were associated with increased stroke risk, we recommend treatment of blood pressure in these patients according to JNC VII guidelines to targets of &lt; 140/90 or &lt;130/80 for those with concomitant diabetes mellitus or kidney disease.

Surgical results of the Carotid Occlusion Surgery Study.

The Carotid Occlusion Surgery Study (COSS) was conducted to determine if superficial temporal artery-middle cerebral artery (STA-MCA) bypass, when added to the best medical therapy, would reduce subsequent ipsilateral stroke in patients with complete internal carotid artery (ICA) occlusion and an elevated oxygen extraction fraction (OEF) in the cerebral hemisphere distal to the occlusion. A recent publication documented the methodology of the COSS in detail and briefly outlined the major findings of the trial. The surgical results of the COSS are described in detail in this report. The COSS was a prospective, parallel-group, 1:1 randomized, open-label, blinded-adjudication treatment trial. Participants, who had angiographically demonstrated complete occlusion of the ICA causing either a transient ischemic attack or ischemic stroke within 120 days and hemodynamic cerebral ischemia indicated by an increased OEF measured by PET, were randomized to either surgical or medical treatment. One hundred ninety-five patients were randomized: 97 to the surgical group and 98 to the medical group. The surgical patients underwent an STA-MCA cortical branch anastomosis. In the intention-to-treat analysis, the 2-year rates for the primary end point were 21% for the surgical group and 22.7% for the medical group (p = 0.78, log-rank test). Fourteen (15%) of the 93 patients who had undergone an arterial bypass had a primary end point ipsilateral hemispheric stroke in the 30-day postoperative period, 12 within 2 days after surgery. The STA-MCA arterial bypass patency rate was 98% at the 30-day postoperative visit and 96% at the last follow-up examination. The STA-MCA arterial bypass markedly improved, although it did not normalize, the level of elevated OEF in the symptomatic cerebral hemisphere. Five surgically treated and 1 nonsurgically treated patients in the surgical group had a primary end point ipsilateral hemispheric stroke after the 30-day postoperative period. No baseline characteristics or intraoperative variables revealed those who would experience a procedure-related stroke. Despite excellent bypass graft patency and improved cerebral hemodynamics, STA-MCA anastomosis did not provide an overall benefit regarding ipsilateral 2-year stroke recurrence, mainly because of a much better than expected stroke recurrence rate (22.7%) in the medical group, but also because of a significant postoperative stroke rate (15%). Clinical trial registration no.: NCT00029146.

Extracranial-Intracranial Bypass Surgery for Stroke Prevention in Hemodynamic Cerebral Ischemia

Context Patients with symptomatic atherosclerotic internal carotid artery occlusion (AICAO) and hemodynamic cerebral ischemia are at high risk for subsequent stroke when treated medically. Objective To test the hypothesis that extracranial-intracranial (EC-IC) bypass surgery, added to best medical therapy, reduces subsequent ipsilateral ischemic stroke in patients with recently symptomatic AICAO and hemodynamic cerebral ischemia. Design Parallel-group, randomized, open-label, blinded-adjudication clinical treatment trial conducted from 2002 to 2010. Setting Forty-nine clinical centers and 18 positron emission tomography (PET) centers in the United States and Canada. The majority were academic medical centers. Participants Patients with arteriographically confirmed AICAO causing hemispheric symptoms within 120 days and hemodynamic cerebral ischemia identified by ipsilateral increased oxygen extraction fraction measured by PET. Of 195 patients who were randomized, 97 were randomized to receive surgery and 98 to no surgery. Follow-up for the primary end point until occurrence, 2 years, or termination of trial was 99% complete. No participant withdrew because of adverse events. Interventions Anastomosis of superficial temporal artery branch to a middle cerebral artery cortical branch for the surgical group. Antithrombotic therapy and risk factor intervention were recommended for all participants. Main Outcome Measure For all participants who were assigned to surgery and received surgery, the combination of (1) all stroke and death from surgery through 30 days after surgery and (2) ipsilateral ischemic stroke within 2 years of randomization. For the nonsurgical group and participants assigned to surgery who did not receive surgery, the combination of (1) all stroke and death from randomization to randomization plus 30 days and (2) ipsilateral ischemic stroke within 2 years of randomization. Results The trial was terminated early for futility. Two-year rates for the primary end point were 21.0% (95% CI, 12.8% to 29.2%; 20 events) for the surgical group and 22.7% (95% CI, 13.9% to 31.6%; 20 events) for the nonsurgical group (P = .78, Z test), a difference of 1.7% (95% CI, −10.4% to 13.8%). Thirty-day rates for ipsilateral ischemic stroke were 14.4% (14/97) in the surgical group and 2.0% (2/98) in the nonsurgical group, a difference of 12.4% (95% CI, 4.9% to 19.9%). Conclusion Among participants with recently symptomatic AICAO and hemodynamic cerebral ischemia, EC-IC bypass surgery plus medical therapy compared with medical therapy alone did not reduce the risk of recurrent ipsilateral ischemic stroke at 2 years. Trial Registration clinicaltrials.gov Identifier: NCT00029146

132 Urgent EC-IC Bypass for Symptomatic Atherosclerotic Ischemic Stroke

INTRODUCTION: Previous studies have shown that extracranial-intracranial (EC-IC) bypass surgery has no preventive effect of subsequent ipsilateral ischemic stroke in patients with symptomatic atherosclerotic internal carotid occlusion and hemodynamic cerebral ischemia. However, few studies have assessed whether an urgent EC-IC bypass surgery is an effective treatment for main trunk stenosis or occlusion in acute stage. METHODS: The authors retrospectively reviewed 58 consecutive patients who underwent urgent EC-IC bypass for symptomatic stenosis or occlusion at internal carotid artery or middle cerebral artery between January 2003 and December 2011. Clinical characteristics and neuroimagings were evaluated and analyzed. RESULTS: Based on preoperative angiogram, the responsible lesions were internal carotid artery in 19 (32.8%) patients and middle cerebral artery in 39 (67.2%). No hemorrhagic complication occurred. Sixty-nine percent of patients showed an improvement of neurological function after surgery and 74.1% of patients had favorable outcome. Unfavorable outcome was associated with insufficient collateral flow and new infarction after bypass surgery. CONCLUSION: Although EC-IC anastomosis for acute ischemic stroke is still debatable, it may be a good option for medication-resistance stenoocclusive disease.

Carotid Revascularization Strategies

Over the past decade, >1 million carotid revascularization procedures have been performed. During this time period, the frequency of carotid endarterectomy (CEA) has slightly declined, whereas carotid artery stenting (CAS) has increased.1 Somewhat surprisingly, in this timeframe, only 2 large (enrolling >1000 patients) randomized controlled trials have been initiated in North America to assess the merits of carotid revascularization approaches. Is this paucity of high-quality data due to limited funding, the influence of competing interests, or are there simply not that many burning questions left? The first of the major randomized controlled trials is the Carotid Revascularization Endarterectomy versus Stent Trial (CREST).2 The principal results of CREST, which enrolled approximately equal numbers of symptomatic and asymptomatic patients, were published in 2010. For the primary end point of periprocedure stroke, myocardial infarction, death, or subsequent ipsilateral stroke, there was not a significant difference between the 2 treatments (6.8% CEA versus 7.2% CAS, P =0.51). However, the components of the primary end point differed in the 2 groups with periprocedure stroke more common with CAS and periprocedure myocardial infarction more frequent after CEA. Where does this leave the second of …