Clinical Outcomes of Arteriovenous Fistula Treatment Using the Penumbra SMART COIL System: A Subgroup Analysis from the Multicenter SMART Registry.

BACKGROUND: Endovascular embolization procedures are typically the primary treatment modality for arteriovenous fistula (AVF). The objective of this subset analysis was to evaluate the prospective long-term clinical outcomes of AVF patients treated with the SMART COIL System. METHODS: Patients who had arteriovenous fistulas (AVF) and underwent endovascular coiling using the Penumbra SMART COIL system were part of a subset analysis within the SMART registry. The SMART registry is a post-market registry that is prospective, multicenter, and single-arm in design. After the treatment, these patients were monitored for a period of 12 ± 6 months. RESULTS: A total of 41 patients were included. No patients (0/41) had a procedural device-related serious adverse event (SAE). Re-access involving a guidewire due to catheter kickout was unnecessary for 85.4% (35/41) of the patients. Complete occlusion after the procedure was achieved in 87.8% (36/41) of patients. The periprocedural SAE rate was 2.4% (1/41), and no periprocedural deaths occurred (0/41). During the follow-up period, there were instances of re-treatment in 3.4% (1/29) of patients. At one year, the lesion occlusion was better or stable in 93.3% (28/30) of patients. The rate of serious adverse events (SAE) from 24 hours to 1 year (±6 months) following the procedure was 26.8% (11/41). The one-year all-cause mortality rate stood at 2.4% (1/ 41), and at the one-year follow-up, 90.9% (20/22) of patients had a modified Rankin Scale score within the range of 0 to 2. CONCLUSION: The coiling procedure for arteriovenous fistulas using the SMART COIL System proved to be safe and effective at the one-year follow-up.

SMART Registry: Safety and Performance of the Penumbra SMART COIL System for Patients With Intracranial Aneurysms 4 mm and Smaller.

BACKGROUND: The Penumbra SMART COIL System includes a novel generation of embolic coils composed of complex and WAVE shape properties with varying levels of softness. OBJECTIVE: To assess safety and efficacy of the SMART COIL System through a 1-year follow-up in patients with small intracranial aneurysms. METHODS: This subset analysis of the SMART Registry, a prospective, multicenter study, includes patients with small intracranial aneurysms (≤4 mm) treated with the SMART COIL System. Registry end points include retreatment rates through 1 year, procedural device-related serious adverse events, and adequate occlusion postprocedure. RESULTS: Of 905 enrolled patients with aneurysms, 172 (19.0%) had small (≤4 mm) aneurysms (75.6% female; mean age 57.2 ± 13.4 years). 30.8% (53/172) of small aneurysms were ruptured, of which 50.9% (27/53) had Hunt and Hess ≥3. 79.5% (132/166) were wide-necked. Stent-assisted coiling and balloon-assisted coiling were performed in 37.2% (64/172) and 22.1% (38/172) of patients, respectively. The mean packing density for very small aneurysms was 44.9 (SD 25.23). Raymond Class I and Class II were achieved in 89.5% (154/172) postprocedure and 97.2% (137/141) at 1 year. The retreatment rate through 1 year was 5.6% (8/142), and the recanalization rate was 7.1% (10/141). The periprocedural device-related serious adverse event rate was 2.9% (5/172). Intraprocedural aneurysm rupture occurred in 0.8% of patients. CONCLUSION: This analysis suggests that the SMART COIL System is safe and efficacious in small aneurysms with satisfactory occlusion rates and low rates of rupture or rerupture. At 1 year, patients had low retreatment rates and good clinical outcomes.

Safety and Long-Term Efficacy Outcomes for Endovascular Treatment of Wide-Neck Bifurcation Aneurysms of the Middle Cerebral Artery: Insights From the SMART Registry.

INTRODUCTION: Wide-necked middle cerebral artery bifurcation aneurysms pose specific challenges to endovascular management. Surgical clipping remains the standard treatment approach for these aneurysms in many centers. While recent data suggests the endovascular treatment may be comparable, a prospective datapoint has been lacking. MATERIALS AND METHODS: The Penumbra SMART registry, a prospective, multi-center, single-arm outcomes registry of Penumbra coil-treated aneurysms, was queried for endovascularly treated MCA bifurcation aneurysms with wide necks (dome:neck ratio <2 or neck >4 mm). Safety and efficacy outcomes were summarized for ruptured and unruptured aneurysms, including rupture, complication rate, and 1-year occlusion outcomes. RESULTS: Seventy-two aneurysms across 31 sites were enrolled. Of these, a total of 15 presented as ruptured aneurysms. Serious adverse events were reported in 21 (29.2%) of patients, with 8 (11.1%) attributed to the device/procedure. Immediately postoperatively, 75.0% of cases achieved "adequate" Raymond Roy Class I (40.3%) or II (34.7%) occlusion outcomes. Of the 72 patients treated, 60 (83.3%) underwent follow-up angiography at 1 year, and among these, 95.0% had 1-year occlusion outcomes of Raymond Roy Class I (71.7%) or II (23.3%). A total of 6 aneurysms (10.0%) were required or were planned for retreatment at the last follow-up. CONCLUSION: This study represents the most significant prospective sample of endovascularly treated wide-neck MCA bifurcation aneurysms conducted to date. It supports the safety and efficacy of endovascular treatment of these aneurysms.

Technical Success and Early Efficacy in 851 Patients with Saccular Intracranial Aneurysms: A Subset Analysis of SMART, a Prospective, Multicenter Registry Assessing the Embolization of Neurovascular Lesions using the Penumbra SMART COIL System.

OBJECTIVE: The Prospective, Multicenter Registry Assessing the Embolization of Neurovascular Lesions Using the Penumbra SMART COIL® System (SMART) is the largest prospective, multicenter, postmarket registry established to gather real-world experience on Penumbra (Alameda, USA) SMART COIL System, PC400, and POD embolization coils. The goal of this study is to report the technical success and efficacy of SMART COIL System coils in treating saccular intracranial aneurysms. METHODS: This subgroup analysis from the SMART registry included patients with saccular intracranial aneurysms treated using ≥75% SMART COIL System or PC400 coils. Baseline and procedural data, angiographic data, and clinical outcomes were collected. Predictors of catheter kickout, packing density, and postprocedural angiographic outcome were analyzed using multivariable regression models in saccular aneurysm cases. RESULTS: Between June 2016 and August 2018, the SMART registry enrolled 995 patients at 68 sites, of which 851 of 995 (85.5%) were treated for saccular aneurysms (mean age, 59.9 years). Aneurysms had a mean size of 6.8 mm, were wide neck in 63.1%, and ruptured in 31.0% of patients. Mean aneurysm packing density was 32.3%. Postprocedural Raymond-Roy Occlusion Classification (RROC) I-II was achieved in 80.3% of patients; smaller aneurysms, non-wide-neck aneurysms, and high packing density were predictive of RROC I-II. Overall, mean fluoroscopic time was 43.4 minutes, rate of reaccess attempts because of catheter kickout was 6.2%, and mean procedure time was 83.2 minutes. CONCLUSIONS: SMART COIL System coils achieved good technical success and adequate occlusion in treating saccular intracranial aneurysms in a real-world setting.

The SMART Registry: Long-Term Results on the Utility of the Penumbra SMART COIL System for Treatment of Intracranial Aneurysms and Other Malformations.

Introduction: Penumbra SMART COIL® (SMART) System is a novel generation embolic coil with varying stiffness. The study purpose was to report real-world usage of the SMART System in patients with intracranial aneurysms (ICA) and non-aneurysm vascular lesions. Materials and Methods: The SMART Registry is a post-market, prospective, multicenter registry requiring ≥75% Penumbra Coils, including SMART, PC400, and/or POD coils. The primary efficacy endpoint was retreatment rate at 1-year and the primary safety endpoint was the procedural device-related serious adverse event rate. Results: Between June 2016 and August 2018, 995 patients (mean age 59.6 years, 72.1% female) were enrolled at 68 sites in the U.S. and Canada. Target lesions were intracranial aneurysms in 91.0% of patients; 63.5% were wide-neck and 31.8% were ruptured. Adjunctive devices were used in 55.2% of patients. Mean packing density was 32.3%. Procedural device-related serious adverse events occurred in 2.6% of patients. The rate of immediate post-procedure adequate occlusion was 97.1% in aneurysms and the rate of complete occlusion was 85.2% in non-aneurysms. At 1-year, the retreatment rate was 6.8%, Raymond Roy Occlusion Classification (RROC) I or II was 90.0% for aneurysms, and Modified Rankin Scale (mRS) 0-2 was achieved in 83.1% of all patients. Predictors of 1-year for RROC III or retreatment (incomplete occlusion) were rupture status (P < 0.0001), balloon-assisted coiling (P = 0.0354), aneurysm size (P = 0.0071), and RROC III immediate post-procedure (P = 0.0086) in a model that also included bifurcation aneurysm (P = 0.7788). Predictors of aneurysm retreatment at 1-year was rupture status (P < 0.0001). Conclusions: Lesions treated with SMART System coils achieved low long-term retreatment rates. Clinical Trial Registration: https://www.clinicaltrials.gov/, identifier NCT02729740.

Safety of the APOLLO Onyx delivery microcatheter for embolization of brain arteriovenous malformations: results from a prospective post-market study.

BACKGROUND: Catheter retention and difficulty in retrieval have been observed during embolization of brain arteriovenous malformations (bAVMs) with the Onyx liquid embolic system (Onyx). The Apollo Onyx delivery microcatheter (Apollo) is a single lumen catheter designed for controlled delivery of Onyx into the neurovasculature, with a detachable distal tip to aid catheter retrieval. This study evaluates the safety of the Apollo for delivery of Onyx during embolization of bAVMs. METHODS: This was a prospective, non-randomized, single-arm, multicenter, post-market study of patients with a bAVM who underwent Onyx embolization with the Apollo between May 2015 and February 2018. The primary endpoint was any catheter-related adverse event (AE) at 30 days, such as unintentional tip detachment or malfunction with clinical sequelae, or retained catheter. Procedure-related AEs (untoward medical occurrence, disease, injury, or clinical signs) and serious AEs (life threatening illness or injury, permanent physiological impairment, hospitalization, or requiring intervention) were also recorded. RESULTS: A total of 112 patients were enrolled (mean age 44.1±17.6 years, 56.3% men), and 201 Apollo devices were used in 142 embolization procedures. The mean Spetzler-Martin grade was 2.38. The primary endpoint was not observed (0/112, 0%). The catheter tip detached during 83 (58.5%) procedures, of which 2 (2.4%) were unintentional and did not result in clinical sequelae. At 30 days, procedure related AEs occurred in 26 (23.2%) patients, and procedure-related serious AEs in 12 (10.7%). At 12 months, there were 3 (2.7%) mortalities, including 2 (1.8%) neurological deaths, none of which were device-related. CONCLUSION: This study demonstrates the safety of Apollo for Onyx embolization of bAVMs. CLINICAL TRIAL REGISTRATION: CNCT02378883.

Timing of Anticoagulation in Patients with Cerebral Venous Thrombosis Requiring Decompressive Surgery: Systematic Review of the Literature and Case Series.

OBJECTIVE: Cerebral venous thrombosis (CVT) is a rare type of stroke whose pathophysiology differs from arterial stroke. CVT is treated with systemic anticoagulant therapy even in the setting of intracerebral hemorrhage. Patients who do not respond adequately may require decompressive surgery. The study objective was to examine the timing of anticoagulation in patients with CVT who require decompressive surgery through systematic literature review and consecutive case series. METHODS: A review of the literature was performed through PubMed using key word search to identify case series and cohort studies examining timing of anticoagulation following decompressive surgery. Our case series included 4 patients who had decompressive surgery for hemorrhagic CVT between 1 January, 2015 and 31 December, 2016 at our comprehensive stroke center. RESULTS: The literature review summarizes 243 patients from 15 studies whose timing of anticoagulation varied. The review suggests anticoagulation can be safely resumed at 48 hours postoperatively based on larger series and as early as 12 hours in smaller series, especially when delivered as a half or prophylactic dose. In our case series, timing of anticoagulation varied slightly but was started or resumed within 38-44 hours postoperatively in 3 patients and was started at the time of decompressive surgery without interruption in 1 patient. No patient had worsening hemorrhage or new hemorrhage while 2 patients rethrombosed. CONCLUSIONS: Despite the lack of high-quality studies, this systematic review of patients with CVT requiring decompressive surgery indicates that anticoagulation can be safely initiated or resumed around 24-48 hours postoperatively; our series supports the existing literature.

Epidemiology, Endovascular Treatment, and Prognosis of Cerebral Venous Thrombosis: US Center Study of 152 Patients.

BACKGROUND: Cerebral venous thrombosis is a rare cause of stroke that poses diagnostic, therapeutic, and prognostic challenges. Mainstay treatment is systemic anticoagulation, but endovascular treatment is increasingly advocated. Our objectives were to describe the epidemiology, treatment, and prognosis of 152 patients with cerebral venous thrombosis. METHODS AND RESULTS: This was a retrospective study of consecutive cerebral venous thrombosis cases from 2006 to 2013 at a comprehensive stroke center through hospital discharge. Predictors of full recovery (modified Rankin Scale scores 0-1) were analyzed with multiple logistic regression and presented as adjusted odds ratios (AORs) with 95% confidence intervals (CIs). The population was young (average age: 42 years), majority female (69%), and commonly presenting with cerebral edema (63%), and 72% were transferred in. All patients received systemic anticoagulation; 49% (n=73) required endovascular treatment. Reasons for requiring endovascular treatment included cerebral edema, herniation, or hemorrhagic infarct (n=38); neurologic decline (n=17); rethrombosis, persistent occlusion, or clot propagation (n=10); extensive clot burden (n=7); and persistent headache despite anticoagulation (n=1). There were 7 (10%) procedural complications. Recanalization was successful (61%), partial (30%), and unsuccessful (9%). Overall, 60% fully recovered. Positive predictors of full recovery included hormonal etiology, particularly for patients who were transferred in (AOR: 7.06 [95% CI, 2.27-21.96], interaction P=0.03) and who had migraine history (AOR: 4.87 [95% CI, 1.01-23.50], P=0.05), whereas negative predictors of full recovery were cerebral edema (AOR: 0.11 [95% CI, 0.04-0.34], P<0.001) and motor weakness (AOR: 0.28 [95% CI, 0.09-0.96], P=0.04). CONCLUSIONS: As one of the largest cohort studies, our findings suggest that cerebral edema, history of migraine, and hormonal etiology were prognostic and that endovascular treatment might be a safe and effective treatment for cerebral venous thrombosis when conventional management is inadequate.

A standardized neurointerventional thrombectomy protocol leads to faster recanalization times.

BACKGROUND AND PURPOSE: Intra-arterial therapy (IAT) is most effective when performed rapidly after ischemic stroke onset. However, there are limited performance benchmarks in IAT and there is a scarcity of information on how to structure an effective IAT protocol and its impact on time to treatment. The objective of our study was to detail a standardized IAT protocol, and to assess its influence on time to treatment in ischemic stroke. METHODS: This was a retrospective observational study over 4 years at a comprehensive stroke center. A standardized IAT protocol was implemented in June 2013 that included pre-notifying the stroke team before hospital arrival, defining clinician roles, processing tasks in parallel, and standardizing IAT procedures. Three time metrics were examined and reported as median (IQR) minutes: arrival to CT imaging, CT to groin puncture, and puncture to recanalization. We compared these metrics in patients admitted before implementation (January 2012-May 2013) to patients admitted after (June 2013-December 2015) using Wilcoxon Mann-Whitney tests. RESULTS: 380 patients were included. After the protocol was implemented, there were significant reductions in time from arrival to CT (17 (14-21) vs 13 (11-19) min, p<0.001), CT to puncture (46 (30-82) vs 31 (23-54) min, p<0.001), and puncture to recanalization (65 (33-90) vs 37 (22-65) min, p<0.001). 60% of time was saved during puncture to recanalization. Significant reductions in time were observed during both normal working hours and off-hours. CONCLUSIONS: Implementation of a standardized protocol resulted in a significant reduction in time to recanalization for patients with an ischemic stroke. A standardized IAT protocol decreases time to recanalization when team roles are clearly defined, tasks are processed in parallel, and procedures are standardized.

Age ≥80 Years Is Not a Contraindication for Intra-Arterial Therapy after Ischemic Stroke.

BACKGROUND: Clinical trials confirmed the safety and efficacy of intra-arterial therapy (IAT) in the management of ischemic stroke. At a community hospital, we compared outcomes in patients aged ≥80 and patients in the age range 55-79 years receiving IAT following ischemic stroke. METHODS: Data were retrospectively abstracted for ischemic stroke patients ≥55 years treated with IAT at an urban comprehensive stroke center between 2010 and 2013. Baseline demographics, incidence of symptomatic intracranial hemorrhage (sICH), in-hospital mortality, discharge modified Rankin scale (mRS) score (favorable ≤2) and improvement in National Institutes of Health Stroke Scale Score (NIHSS; decreased score at discharge) were compared between patients in the age range 55-79 and patients ≥80 years. Data were analyzed using univariate analyses and multivariate logistic regression. RESULTS: IAT was performed in 239 patients with ischemic stroke; 63 (26.4%) were ≥80 years. When compared to patients aged 55-79, the elderly patients were more often female and non-smokers, with a history of atrial fibrillation. No differences were observed in those ≥80 years compared to patients in the age range 55-79 years for sICH (10 vs. 5%, p = 0.23), mortality (24 vs. 18%, p = 0.28), favorable discharge mRS score (13 vs. 19%, p = 0.27), or improvement in NIHSS (83 vs. 92%, p = 0.10). The nonsignificant association of age with the outcomes persisted after adjusting for covariates and when analyzing the subset of patients who received IAT only. CONCLUSIONS: These findings suggest that in a cohort not subject to the criteria of a clinical trial, age ≥80 years should not be a contraindication to IAT.