Impact of Balloon Guide Catheter Use on Clinical and Angiographic Outcomes in the STRATIS Stroke Thrombectomy Registry.

Background and Purpose- Mechanical thrombectomy has been shown to improve clinical outcomes in patients with acute ischemic stroke. However, the impact of balloon guide catheter (BGC) use is not well established. Methods- STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) was a prospective, multicenter study of patients with large vessel occlusion treated with the Solitaire stent retriever as first-line therapy. In this study, an independent core laboratory, blinded to the clinical outcomes, reviewed all procedures and angiographic data to classify procedural technique, target clot location, recanalization after each pass, and determine the number of stent retriever passes. The primary clinical end point was functional independence (modified Rankin Scale, 0-2) at 3 months as determined on-site, and the angiographic end point was first-pass effect (FPE) success rate from a single device attempt (modified Thrombolysis in Cerebral Infarction, ≥2c) as determined by a core laboratory. Achieving modified FPE (modified Thrombolysis in Cerebral Infarction, ≥2b) was also assessed. Comparisons of clinical outcomes were made between groups and adjusted for baseline and procedural characteristics. All participating centers received institutional review board approval from their respective institutions. Results- Adjunctive technique groups included BGC (n=445), distal access catheter (n=238), and conventional guide catheter (n=62). The BGC group had a higher rate of FPE following first pass (212/443 [48%]) versus conventional guide catheter (16/62 [26%]; P=0.001) and distal access catheter (83/235 [35%]; P=0.002). Similarly, the BGC group had a higher rate of modified FPE (294/443 [66%]) versus conventional guide catheter (26/62 [42%]; P<0.001) and distal access catheter (129/234 [55%]; P=0.003). The BGC group achieved the highest rate of functional independence (253/415 [61%]) versus conventional guide catheter (23/55 [42%]; P=0.007) and distal access catheter (113/218 [52%]; P=0.027). Final revascularization and mortality rates did not differ across the groups. Conclusions- BGC use was an independent predictor of FPE, modified FPE, and functional independence, suggesting that its routine use may improve the rates of early revascularization success and good clinical outcomes. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02239640.

Interhospital Transfer Before Thrombectomy Is Associated With Delayed Treatment and Worse Outcome in the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke).

BACKGROUND: Endovascular treatment with mechanical thrombectomy (MT) is beneficial for patients with acute stroke suffering a large-vessel occlusion, although treatment efficacy is highly time-dependent. We hypothesized that interhospital transfer to endovascular-capable centers would result in treatment delays and worse clinical outcomes compared with direct presentation. METHODS: STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) was a prospective, multicenter, observational, single-arm study of real-world MT for acute stroke because of anterior-circulation large-vessel occlusion performed at 55 sites over 2 years, including 1000 patients with severe stroke and treated within 8 hours. Patients underwent MT with or without intravenous tissue plasminogen activator and were admitted to endovascular-capable centers via either interhospital transfer or direct presentation. The primary clinical outcome was functional independence (modified Rankin Score 0-2) at 90 days. We assessed (1) real-world time metrics of stroke care delivery, (2) outcome differences between direct and transfer patients undergoing MT, and (3) the potential impact of local hospital bypass. RESULTS: A total of 984 patients were analyzed. Median onset-to-revascularization time was 202.0 minutes for direct versus 311.5 minutes for transfer patients (P<0.001). Clinical outcomes were better in the direct group, with 60.0% (299/498) achieving functional independence compared with 52.2% (213/408) in the transfer group (odds ratio, 1.38; 95% confidence interval, 1.06-1.79; P=0.02). Likewise, excellent outcome (modified Rankin Score 0-1) was achieved in 47.4% (236/498) of direct patients versus 38.0% (155/408) of transfer patients (odds ratio, 1.47; 95% confidence interval, 1.13-1.92; P=0.005). Mortality did not differ between the 2 groups (15.1% for direct, 13.7% for transfer; P=0.55). Intravenous tissue plasminogen activator did not impact outcomes. Hypothetical bypass modeling for all transferred patients suggested that intravenous tissue plasminogen activator would be delayed by 12 minutes, but MT would be performed 91 minutes sooner if patients were routed directly to endovascular-capable centers. If bypass is limited to a 20-mile radius from onset, then intravenous tissue plasminogen activator would be delayed by 7 minutes and MT performed 94 minutes earlier. CONCLUSIONS: In this large, real-world study, interhospital transfer was associated with significant treatment delays and lower chance of good outcome. Strategies to facilitate more rapid identification of large-vessel occlusion and direct routing to endovascular-capable centers for patients with severe stroke may improve outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke: Primary Results of the STRATIS Registry.

BACKGROUND AND PURPOSE: Mechanical thrombectomy with stent retrievers has become standard of care for treatment of acute ischemic stroke patients because of large vessel occlusion. The STRATIS registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) aimed to assess whether similar process timelines, technical, and functional outcomes could be achieved in a large real world cohort as in the randomized trials. METHODS: STRATIS was designed to prospectively enroll patients treated in the United States with a Solitaire Revascularization Device and Mindframe Capture Low Profile Revascularization Device within 8 hours from symptom onset. The STRATIS cohort was compared with the interventional cohort of a previously published SEER patient-level meta-analysis. RESULTS: A total of 984 patients treated at 55 sites were analyzed. The mean National Institutes of Health Stroke Scale score was 17.3. Intravenous tissue-type plasminogen activator was administered in 64.0%. The median time from onset to arrival in the enrolling hospital, door to puncture, and puncture to reperfusion were 138, 72, and 36 minutes, respectively. The Core lab-adjudicated modified Thrombolysis in Cerebral Infarction ≥2b was achieved in 87.9% of patients. At 90 days, 56.5% achieved a modified Rankin Scale score of 0 to 2, all-cause mortality was 14.4%, and 1.4% suffered a symptomatic intracranial hemorrhage. The median time from emergency medical services scene arrival to puncture was 152 minutes, and each hour delay in this interval was associated with a 5.5% absolute decline in the likelihood of achieving modified Rankin Scale score 0 to 2. CONCLUSIONS: This largest-to-date Solitaire registry documents that the results of the randomized trials can be reproduced in the community. The decrease of clinical benefit over time warrants optimization of the system of care. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Aggressive medical treatment with or without stenting in high-risk patients with intracranial artery stenosis (SAMMPRIS): the final results of a randomised trial.

BACKGROUND: Early results of the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis trial showed that, by 30 days, 33 (14·7%) of 224 patients in the stenting group and 13 (5·8%) of 227 patients in the medical group had died or had a stroke (percentages are product limit estimates), but provided insufficient data to establish whether stenting offered any longer-term benefit. Here we report the long-term outcome of patients in this trial. METHODS: We randomly assigned (1:1, stratified by centre with randomly permuted block sizes) 451 patients with recent transient ischaemic attack or stroke related to 70-99% stenosis of a major intracranial artery to aggressive medical management (antiplatelet therapy, intensive management of vascular risk factors, and a lifestyle-modification programme) or aggressive medical management plus stenting with the Wingspan stent. The primary endpoint was any of the following: stroke or death within 30 days after enrolment, ischaemic stroke in the territory of the qualifying artery beyond 30 days of enrolment, or stroke or death within 30 days after a revascularisation procedure of the qualifying lesion during follow-up. Primary endpoint analysis of between-group differences with log-rank test was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT 00576693. FINDINGS: During a median follow-up of 32·4 months, 34 (15%) of 227 patients in the medical group and 52 (23%) of 224 patients in the stenting group had a primary endpoint event. The cumulative probability of the primary endpoints was smaller in the medical group versus the percutaneous transluminal angioplasty and stenting (PTAS) group (p=0·0252). Beyond 30 days, 21 (10%) of 210 patients in the medical group and 19 (10%) of 191 patients in the stenting group had a primary endpoint. The absolute differences in the primary endpoint rates between the two groups were 7·1% at year 1 (95% CI 0·2 to 13·8%; p=0·0428), 6·5% at year 2 (-0·5 to 13·5%; p=0·07) and 9·0% at year 3 (1·5 to 16·5%; p=0·0193). The occurrence of the following adverse events was higher in the PTAS group than in the medical group: any stroke (59 [26%] of 224 patients vs 42 [19%] of 227 patients; p=0·0468) and major haemorrhage (29 [13%]of 224 patients vs 10 [4%] of 227 patients; p=0·0009). INTERPRETATION: The early benefit of aggressive medical management over stenting with the Wingspan stent for high-risk patients with intracranial stenosis persists over extended follow-up. Our findings lend support to the use of aggressive medical management rather than PTAS with the Wingspan system in high-risk patients with atherosclerotic intracranial arterial stenosis. FUNDING: National Institute of Neurological Disorders and Stroke (NINDS) and others.

Stenting versus aggressive medical therapy for intracranial arterial stenosis.

BACKGROUND: Atherosclerotic intracranial arterial stenosis is an important cause of stroke that is increasingly being treated with percutaneous transluminal angioplasty and stenting (PTAS) to prevent recurrent stroke. However, PTAS has not been compared with medical management in a randomized trial. METHODS: We randomly assigned patients who had a recent transient ischemic attack or stroke attributed to stenosis of 70 to 99% of the diameter of a major intracranial artery to aggressive medical management alone or aggressive medical management plus PTAS with the use of the Wingspan stent system. The primary end point was stroke or death within 30 days after enrollment or after a revascularization procedure for the qualifying lesion during the follow-up period or stroke in the territory of the qualifying artery beyond 30 days. RESULTS: Enrollment was stopped after 451 patients underwent randomization, because the 30-day rate of stroke or death was 14.7% in the PTAS group (nonfatal stroke, 12.5%; fatal stroke, 2.2%) and 5.8% in the medical-management group (nonfatal stroke, 5.3%; non-stroke-related death, 0.4%) (P=0.002). Beyond 30 days, stroke in the same territory occurred in 13 patients in each group. Currently, the mean duration of follow-up, which is ongoing, is 11.9 months. The probability of the occurrence of a primary end-point event over time differed significantly between the two treatment groups (P=0.009), with 1-year rates of the primary end point of 20.0% in the PTAS group and 12.2% in the medical-management group. CONCLUSIONS: In patients with intracranial arterial stenosis, aggressive medical management was superior to PTAS with the use of the Wingspan stent system, both because the risk of early stroke after PTAS was high and because the risk of stroke with aggressive medical therapy alone was lower than expected. (Funded by the National Institute of Neurological Disorders and Stroke and others; SAMMPRIS ClinicalTrials.gov number, NCT00576693.).

Detailed analysis of periprocedural strokes in patients undergoing intracranial stenting in Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS).

BACKGROUND AND PURPOSE: Enrollment in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial was halted due to the high risk of stroke or death within 30 days of enrollment in the percutaneous transluminal angioplasty and stenting arm relative to the medical arm. This analysis focuses on the patient and procedural factors that may have been associated with periprocedural cerebrovascular events in the trial. METHODS: Bivariate and multivariate analyses were performed to evaluate whether patient and procedural variables were associated with cerebral ischemic or hemorrhagic events occurring within 30 days of enrollment (termed periprocedural) in the percutaneous transluminal angioplasty and stenting arm. RESULTS: Of 224 patients randomized to percutaneous transluminal angioplasty and stenting, 213 underwent angioplasty alone (n=5) or with stenting (n=208). Of these, 13 had hemorrhagic strokes (7 parenchymal, 6 subarachnoid), 19 had ischemic stroke, and 2 had cerebral infarcts with temporary signs within the periprocedural period. Ischemic events were categorized as perforator occlusions (13), embolic (4), mixed perforator and embolic (2), and delayed stent occlusion (2). Multivariate analyses showed that higher percent stenosis, lower modified Rankin score, and clopidogrel load associated with an activated clotting time above the target range were associated (P ≤ 0.05) with hemorrhagic stroke. Nonsmoking, basilar artery stenosis, diabetes, and older age were associated (P ≤ 0.05) with ischemic events. CONCLUSIONS: Periprocedural strokes in SAMMPRIS had multiple causes with the most common being perforator occlusion. Although risk factors for periprocedural strokes could be identified, excluding patients with these features from undergoing percutaneous transluminal angioplasty and stenting to lower the procedural risk would limit percutaneous transluminal angioplasty and stenting to a small subset of patients. Moreover, given the small number of events, the present data should be used for hypothesis generation rather than to guide patient selection in clinical practice. Clinical Trial Registration Information- URL: http://clinicaltrials.gov. Unique Identifier: NCT00576693.

Feasibility and Efficacy of Low-profile Visual Intraluminal Support Device: A Single Center Five-year Experience.

INTRODUCTION: The Low-Profile Visualized Intraluminal Support (LVIS) devices are a new generation of self-expandable, high-porosity stents approved for the treatment of large to giant wide-necked intracranial aneurysms via stent-assisted coiling. Here we report the radiographic and clinical outcomes seen with LVIS, LVIS Jr. and LVIS Blue from a single institution over a fiveyear period. METHODS: Patients with intracranial aneurysms treated by LVIS, LVIS Jr. and LVIS Blue technology over a five-year period (2012 - 2017) at our institution were retrospectively reviewed. RESULTS: Seventy-four patients (55 females and 19 males; average age = 59.2) with 74 aneurysms underwent embolization of intracranial aneurysms using LVIS (N = 10), LVIS Jr. (N = 47) or LVIS Blue (N = 12) devices at our institution over the study period. The most common location of treated aneurysms was the anterior communicating artery (31%), followed by the basilar artery (19%), and the middle cerebral artery (13%). The mean neck and dome sizes were 3.9±1.5mm and 6.6±3.2mm, respectively. The median follow-up time was 6 months. At the last radiographic follow- up, 93.1% of patients had complete occlusion (RR-I or OKM-D). In 5 cases (7%), the LVIS stent failed to open, requiring balloon angioplasty (N = 3) or stent recapture and use of a non-LVIS branded device (N = 2). Five patients had post-embolization infarcts, and 1 patient had an intra-operative dome rupture. CONCLUSION: LVIS brand of stents is a safe, effective, and technically feasible treatment strategy for wide-neck intracranial aneurysms, with high deployment success and aneurysm obliteration rates.

The professional and personal impact of the coronavirus pandemic on US neurointerventional practices: a nationwide survey.

BACKGROUND: Little is currently known about the effects of the coronavirus (COVID-19) pandemic on neurointerventional (NI) procedural volumes or its toll on physician wellness. METHODS: A 37-question online survey was designed and distributed to physician members of three NI physician organizations. RESULTS: A total of 151 individual survey responses were obtained. Reduced mechanical thrombectomy procedures compared with pre-pandemic were observed with 32% reporting a greater than 50% reduction in thrombectomy volumes. In concert with most (76%) reporting at least a 25% reduction in non-mechanical thrombectomy urgent NI procedures and a nearly unanimous (96%) cessation of non-urgent elective cases, 68% of physicians reported dramatic reductions (>50%) in overall NI procedural volume compared with pre-pandemic. Increased door-to-puncture times were reported by 79%. COVID-19-positive infections occurred in 1% of physician respondents: an additional 8% quarantined for suspected infection. Sixty-six percent of respondents reported increased career stress, 56% increased personal life/family stress, and 35% increased career burnout. Stress was significantly increased in physicians with COVID-positive family members (P<0.05). CONCLUSIONS: This is the first study designed to understand the effects of the COVID-19 pandemic on NI physician practices, case volumes, compensation, personal/family stresses, and work-related burnout. Future studies examining these factors following the resumption of elective cases and relaxing of social distancing measures will be necessary to better understand these phenomena.

Augmented Reality with Virtual Cerebral Aneurysms: A Feasibility Study.

OBJECTIVE: Advanced magnetic resonance imaging (MRI) acquisition methods such as 4D phase contrast magnetic resonance imaging (4D pcMRI) have found widespread applications in assessing hemodynamics in cerebral aneurysms. One of the goals is the identification of a hemodynamic scenario predictive of aneurysm rupture. Because of the technical complexity the 4D pcMRI technology, challenges exist in extracting and communicating the wealth of information contained in the MRI image data, in particular, to a multidisciplinary team of health professionals and basic scientists. METHODS: Here we introduce a new resource in the form of a commercially available optical see-through head-mounted display, which allows augmenting the real world by computer-generated virtual objects. RESULTS: An image processing algorithm was presented for integrating 3D surface models derived from 3D rotational angiography data, 3D time-of-flight MRI data, and 4D pcMRI data into the augmented reality environment. This new approach was successfully evaluated on blood flow data acquired before and after flow diverter treatment in 6 patients harboring a cerebral aneurysm. CONCLUSIONS: Augmented reality may become an additional means for visualizing complex medical data, in particular complex flows as illustrated here.

Unique percutaneous direct puncture technique for occlusion of a hypoglossal canal dural arteriovenous fistula.

PURPOSE: To report percutaneous transcranial puncture, embolization and occlusion of a very symptomatic hypoglossal canal/anterior condylar vein dural arteriovenous fistula (DAVF) using syngo iGuide navigational software in a patient in whom transarterial and transvenous embolization and surgery had failed. METHODS: After unsuccessful arterial and venous embolization and surgical treatment of a symptomatic hypoglossal canal DAVF, a 47-year-old man was transferred for further management. With exquisite anatomic detail provided by C-arm cone-beam computed tomography (CBCT) equipment (Artis zee Biplane, Dyna CT VC21H, Siemens Healthcare GmbH, Germany) and syngo iGuide needle guidance navigational software (Siemens Healthcare GmbHy) for planning a safe direct approach, the hypoglossal/anterior condylar vein, the dominant outflow vein of the fistula, was needle punctured percutaneously at the hypoglossal foramen and occluded with ethylene vinyl alcohol copolymer liquid embolic agent (Onyx, Medtronic, Minneapolis, Minnesota, USA) after placing two anchoring platinum coils (Target detachable coils, Stryker Neurovascular, Fremont, California, USA). RESULTS: After a year of progressively severe left eye proptosis, chemosis and increased intraocular pressure, the symptoms quickly subsided after this embolization and the patient was symptom free at his 3-month and later checkups. CONCLUSION: With guidance and imaging provided by CBCT and syngo iGuide navigational software, an otherwise untreatable DAVF was successfully embolized and obliterated by an aggressive unique percutaneous trans-cranial needle puncture of the dominant outflow vein in the hypoglossal canal.

Contextualizing the first-round failure of the AHCA: down but not out.

On 8 November 2016 the American electorate voted Donald Trump into the Presidency and a majority of Republicans into both houses of Congress. Since many Republicans ran for elected office on the promise to 'repeal and replace' Obamacare, this election result came with an expectation that campaign rhetoric would result in legislative action on healthcare. The American Health Care Act (AHCA) represented the Republican effort to repeal and replace the Affordable Care Act (ACA). Key elements of the AHCA included modifications of Medicaid expansion, repeal of the individual mandate, replacement of ACA subsidies with tax credits, and a broadening of the opportunity to use healthcare savings accounts. Details of the bill and the political issues which ultimately impeded its passage are discussed here.

Use of a pressure sensing sheath: comparison with standard means of blood pressure monitoring in catheterization procedures.

PURPOSE: Monitoring of blood pressure (BP) during procedures is variable, depending on multiple factors. Common methods include sphygmomanometer (BP cuff), separate radial artery catheterization, and side port monitoring of an indwelling sheath. Each means of monitoring has disadvantages, including time consumption, added risk, and signal dampening due to multiple factors. We sought an alternative approach to monitoring during procedures in the catheterization laboratory. METHODS: A new technology involving a 330 µm fiberoptic sensor embedded in the wall of a sheath structure was tested against both radial artery catheter and sphygmomanometer readings obtained simultaneous with readings recorded from the pressure sensing system (PSS). Correlations and Bland-Altman analysis were used to determine whether use of the PSS could substitute for these standard techniques. RESULTS: The results indicated highly significant correlations in systolic, diastolic, and mean arterial pressures (MAP) when compared against radial artery catheterization (p<0.0001), and MAP means differed by <4%. Bland-Altman analysis of the data suggested that the sheath measurements can replace a separate radial artery catheter. While less striking, significant correlations were seen when PSS readings were compared against BP cuff readings. CONCLUSIONS: The PSS has competitive functionality to that seen with a dedicated radial artery catheter for BP monitoring and is available immediately on sheath insertion without the added risk of radial catheterization. The sensor is structurally separated from the primary sheath lumen and readings are unaffected by device introduction through the primary lumen. Time delays and potential complications from radial artery catheterization are avoided.

MACRA: background, opportunities and challenges for the neurointerventional specialist.

The legislative branch of government took many by surprise when it announced the Medicare Access and CHIP Reauthorization Act of 2015. Once the Act was passed, President Obama quickly signed this bipartisan, bicameral effort into law. A foundational element of this legislation was the permanent repeal of the sustainable growth rate formula. Physicians and their patients were appropriately enthusiastic about this development. The Medicare Access and CHIP Reauthorization Act of 2015 included additional elements of considerable interest to neurointerventional specialists.

Endovascular treatment of high-flow carotid cavernous fistulas by stent-assisted coil placement.

BACKGROUND AND PURPOSE: Endovascular techniques are the methods of choice for the treatment of patients with carotid cavernous fistulas. We report our experience using stent-assisted coil placement for treatment of patients with high-flow fistulas that are associated with severe laceration of the internal carotid artery. METHODS: In a retrospective review of an internal endovascular therapy database covering the interval between October 2001 and October 2003, we identified a total of 5 patients presenting with 6 high-flow type A carotid cavernous fistulas (one had a bilateral fistula) that were associated with severe laceration of the internal carotid artery. All were treated first with stenting of the injured segment of the internal carotid artery followed by transarterial (3/6) and/or transvenous (4/6) obliteration of the fistula with detachable platinum coils. In 2 cases, a liquid adhesive was also used. In all instances, a compliant balloon was inflated within the stented arterial segment during coil deposition to avoid extension of coils into the parent artery. RESULTS: All 6 fistulas were obliterated, and each internal carotid artery was successfully reconstructed. Except for posttraumatic cranial nerve dysfunction in 1 patient, clinical outcome was very good. Follow-up angiograms in 3 of the 6 patients obtained at intervals between 3 and 6 months (mean, 4.5 months) revealed no fistula recurrence and no evidence of intimal hyperplasia within the stent. CONCLUSION: In this series of patients with high-flow carotid cavernous fistula associated with severe injury to the internal carotid artery, stent-assisted coil placement offered a safe and effective treatment. Stent-assisted coil placement may increase the ability to successfully treat fistulas with severe injury to the internal carotid artery with preservation of the parent artery.

Comprehensive Overview of Contemporary Management Strategies for Cerebral Aneurysms.

Aneurysmal subarachnoid hemorrhage (SAH) remains an important health issue in the United States. Despite recent improvements in the diagnosis and treatment of cerebral aneurysms, the mortality rate following aneurysm rupture. In those patients who survive, up to 50% are left severely disabled. The goal of preventing the hemorrhage or re-hemorrhage can only be achieved by successfully excluding the aneurysm from the circulation. This article is a comprehensive review by contemporary vascular neurosurgeons and interventional neuroradiolgists on the modern management of cerebral aneurysms.

Enrollment volume effect on risk factor control and outcomes in the SAMMPRIS trial.

OBJECTIVE: The role of physician experience and patient volumes on the outcome of surgical or endovascular procedures has been well-studied but there are limited data on how these factors affect the outcome of medical therapy. METHODS: In the stenting and medical cohorts of the Stenting and Aggressive Medical Management for the Prevention of Recurrent Ischemic Stroke (SAMMPRIS) trial, we compared Kaplan-Meier (K-M) curves for the primary endpoint (any stroke or death within 30 days of enrollment or ischemic stroke in the territory beyond 30 days) using the log-rank test and the percentages of patients achieving target levels for primary and secondary risk factors during the study using Fisher exact test between patients at high-enrolling (≥12 patients) vs low-enrolling (<12 patients) sites. RESULTS: In the stenting group, the K-M curves for the primary endpoint were similar at high-enrolling sites and low-enrolling sites (p = 0.93) with rates of 13.5% vs 14.7% at 30 days and 19.0% vs 20.6% at 2 years. In the medical group, the K-M curves differed between high-enrolling sites and low-enrolling sites (p = 0.0005) with rates of 1.8% vs 9.8% at 30 days and 7.3% vs 20.9% at 2 years. The percentages of patients who achieved targets for low-density lipoprotein cholesterol and systolic blood pressure at high- vs low-enrolling sites in both treatment groups combined were 64% vs 49% (p = 0.003) and 70% vs 59% (p = 0.026), respectively. CONCLUSIONS: High-enrolling sites in SAMMPRIS achieved better control of primary risk factors and much lower rates of the primary endpoint than low-enrolling sites in the medical group, suggesting that experience with medical management is an important determinant of patient outcome.

Current technology and clinical applications of three-dimensional angiography.

Three-dimensional (3D) angiography was first proposed by Cornelius and advanced into clinical practice by Voigt in 1975. Since then, a variety of improvements have been developed as a result of the increased speed and data transfer afforded by modern computers. Recent publications by Fahrig and others have brought 3D angiographic imaging to the forefront. The 3D evaluation of cerebral aneurysms and arteriovenous malformations no longer is a clinical curiosity, but an absolute necessity.