The pEGASUS-HPC stent system for intracranial arterial stenosis: a single-center case series.

BACKGROUND: Intracranial arterial stenting is a technique for the treatment of symptomatic stenosis. In this single-center retrospective case series we evaluated a novel low profile laser-cut stent with an antithrombogenic hydrophilic polymer coating (pEGASUS-HPC, Phenox GmbH, Bochum, Germany) for the treatment of intracranial stenosis in the setting of acute ischemic stroke and elective cases. METHODS: All patients treated with pEGASUS-HPC for one or more intracranial arterial stenoses at our institution were retrospectively included. Clinical, imaging and procedural parameters as well as clinical and imaging follow-up data were collected. RESULTS: We performed 43 interventions in 41 patients with 42 stenoses in our neurovascular center between August 2021 and February 2024. Twenty-one patients (51.2%) were female and the mean±SD age was 71±10.8 years. Thirty-seven (86.1%) procedures were performed in the setting of endovascular acute ischemic stroke treatment. Technical or procedural complications occurred in seven patients (16.3%), six in the thrombectomy group and one in the elective group. One stent-related hemorrhagic complication (subarachnoid hemorrhage) occurred in emergency cases and symptomatic intracerebral hemorrhage occurred in one patient treated in an elective setting. Overall stenosis reduction following pEGASUS-HPC stent implantation was 53.0±18.0%. On follow-up imaging, which was available for 16 patients (37.2%) after an average of 32±58.6 days, 62.5% of the stents were patent. CONCLUSION: Our single-center case series demonstrates the feasibility of using the pEGASUS-HPC stent system, especially in emergency situations when thrombectomy fails.

Impact of Vaccination Status on Outcome of Patients With COVID-19 and Acute Ischemic Stroke Undergoing Mechanical Thrombectomy.

BACKGROUND: Data on impact of COVID-19 vaccination and outcomes of patients with COVID-19 and acute ischemic stroke undergoing mechanical thrombectomy are scarce. Addressing this subject, we report our multicenter experience. METHODS AND RESULTS: This was a retrospective analysis of patients with COVID-19 and known vaccination status treated with mechanical thrombectomy for acute ischemic stroke at 20 tertiary care centers between January 2020 and January 2023. Baseline demographics, angiographic outcome, and clinical outcome evaluated by the modified Rankin Scale score at discharge were noted. A multivariate analysis was conducted to test whether these variables were associated with an unfavorable outcome, defined as modified Rankin Scale score >3. A total of 137 patients with acute ischemic stroke (48 vaccinated and 89 unvaccinated) with acute or subsided COVID-19 infection who underwent mechanical thrombectomy attributable to vessel occlusion were included in the study. Angiographic outcomes between vaccinated and unvaccinated patients were similar (modified Thrombolysis in Cerebral Infarction ≥2b: 85.4% in vaccinated patients versus 86.5% in unvaccinated patients; P=0.859). The rate of functional independence (modified Rankin Scale score, ≤2) was 23.3% in the vaccinated group and 20.9% in the unvaccinated group (P=0.763). The mortality rate was 30% in both groups. In the multivariable analysis, vaccination status was not a significant predictor for an unfavorable outcome (P=0.957). However, acute COVID-19 infection remained significant (odds ratio, 1.197 [95% CI, 1.007-1.417]; P=0.041). CONCLUSIONS: Our study demonstrated no impact of COVID-19 vaccination on angiographic or clinical outcome of COVID-19-positive patients with acute ischemic stroke undergoing mechanical thrombectomy, whereas worsening attributable to COVID-19 was confirmed.

The pEGASUS-HPC stent system for stent-assisted coiling of cerebral aneurysms: a multicenter case series.

BACKGROUND: Stent-assisted coiling (SAC) is a well-established method for treatment of wide-necked intracranial aneurysms. In this multicenter, retrospective case series we evaluated SAC with a new low-profile, laser-cut stent with an antithrombogenic hydrophilic polymer coating (pEGASUS-HPC) for the treatment of intracranial aneurysms. METHODS: Patients treated with pEGASUS-HPC SAC for one or more intracranial aneurysms were retrospectively included. Clinical, imaging, and procedural parameters as well as clinical and imaging follow-up data were recorded. RESULTS: We treated 53 aneurysms in 52 patients in six neurovascular centers between August 2021 and November 2022. Thirty-seven patients (69.8%) were female. Mean age was 57 (±11.7) years. Twenty-nine patients were treated electively, 23 in the acute phase (22 with aneurysmal subarachnoid hemorrhage (SAH), and 1 with a partially thrombosed aneurysm causing ischemic events). One intraprocedural thromboembolic event and three postprocedural ischemic complications occurred in two (8.7 %) of the SAH patients and in one of the elective patients (3.45%). Overall aneurysm occlusion was Raymond Roy (RR) I in 36 (69.2%), RR II in 9, and RR III in 9 cases. Follow-up imaging was available for 23 patients after an average of 147.7 (±59.6) days demonstrating RR I occlusion in 22 (95.5%) and RR II in 1 patient. CONCLUSION: SAC with the pEGASUS-HPC stent system demonstrates rates of periprocedural safety and effectiveness that are comparable with previously reported series for stent-assisted coil embolization.

Thrombectomy With the pRESET vs Solitaire Stent Retrievers as First-Line Large Vessel Occlusion Stroke Treatment: A Randomized Clinical Trial.

Importance: Stent retriever-based thrombectomy is highly beneficial in large vessel occlusion (LVO) strokes. Many stent retriever designs are currently available, but comparison of these technologies in well-conducted studies is lacking. Objective: To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever. Design, Setting, and Participants: This study was a multicenter, prospective, randomized, controlled, open-label, adaptive, noninferiority trial with blinded primary end point evaluation. Between October 2019 and February 2022, multicenter participation occurred across 19 research hospitals and/or universities in the US and 5 in Germany. Patients with LVO stroke were enrolled and included up to 8 hours after symptom onset. Interventions: Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever. Main Outcomes and Measures: The primary outcome was the difference in the rate of 90-day functional independence across the 2 devices, using a -12.5% noninferiority margin for the lower bound of the 1-sided 95% CI of the difference between pRESET and Solitaire retrievers. Results: Of 340 randomized patients, 170 (50.0%) were female, and the median (IQR) age was 73.0 (64.0-82.0) years. The study procedure was completed in 322 of the 340 randomized patients. The primary end point of 90-day functional independence was achieved by 95 patients (54.9%; 95% CI, 48.7-61.1) in the pRESET group and in 96 (57.5%; 95% CI, 51.2-63.8) in the Solitaire group (absolute difference, -2.57%; 95% CI, -11.42 to 6.28). As the lower bound of the 95% CI was greater than -12.5%, the pRESET retriever was deemed noninferior to the Solitaire retriever. The noninferiority of pRESET over Solitaire was also observed in the secondary clinical end point (90-day shift in modified Rankin Scale score) and in both angiographic end points (Expanded Treatment in Cerebral Infarction [eTICI] score of 2b50 or greater within 3 passes: 146 of 173 [84.4%] vs 149 of 167 [89.2%]; absolute difference, -4.83%; 95% CI, -10.84 to 1.19; eTICI of 2c or greater following the first pass: 76 of 173 [43.7%] vs 74 of 167 [44.3%]; absolute difference, -0.63%; 95% CI, -9.48 to 8.21). Symptomatic intracranial hemorrhage occurred in 0 patients in the pRESET group and 2 (1.2%) in the Solitaire group. Mortality occurred in 25 (14.5%) in the pRESET group and in 24 (14.4%) in the Solitaire group at 90 days. Findings of the per-protocol and as-treated analyses were in concordance with findings of the intention-to-treat analysis. Conclusions and Relevance: In this study, among patients with LVO stroke, thrombectomy with the pRESET stent retriever was noninferior to thrombectomy with the Solitaire stent retriever. Findings suggest that pRESET offers a safe and effective option for flow restoration and disability reduction in patients with LVO stroke.

Non-ischemic cerebral enhancing (NICE) lesions after flow diversion for intracranial aneurysms: a multicenter study.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions have been reported as a rare complication of various neuroendovascular procedures, but information on their incidence after flow diversion is scant. It is unclear if specific devices or novel coating technologies may impact their occurrence. METHODS: We conducted a multicenter study on the incidence of NICE lesions after flow diverter (FD) implantation for cerebral aneurysm treatment. RESULTS: Eight centers identified 15 patients and provided detailed data. The clinical presentation ranged from asymptomatic to hemiplegia and cognitive impairment. The mean time to diagnosis after treatment was 65.1±101.5 days. Five centers disclosed information on all of their 1201 FD procedures during the inclusion period (2015-2022), during which 12 patients were diagnosed with NICE lesions in these institutions-that is, an incidence of 1%. FD coatings did not increase the incidence (6/591 patients (1%) treated with surface-modified FD vs 6/610 patients (1%) treated with bare FD; P=1.00). Significantly increased rates of 3.7% (6 cases in 161 procedures; P<0.01) and 3.3% (5 cases in 153 procedures; P<0.01) were found with stents of two specific product lines. The use of one product line was associated with a significantly lower incidence (0 cases in 499 procedures (0%); P<0.01). CONCLUSIONS: Novel stent coatings are not associated with an increased incidence of NICE lesions. The incidence rate of 1% suggests that these lesions may occur more often after flow diversion than after other endovascular treatments. We found a concerning accumulation of NICE lesion cases when FDs from two product families were used.

The History of Endovascular Stroke Treatment: From Local Intraarterial Fibrinolysis to Stent Retriever Thrombectomy.

BACKGROUND: Acute thromboembolic occlusions of large intracranial arteries are associated with high rates of permanent disability and mortality. Intravenous thrombolysis (IVT) in these patients resulted in an inadequate rate of recanalization and has had limited clinical success. Various endovascular procedures have been attempted to remove intracranial thrombi and reopen occluded vessels. These technical innovations led to the publication of initial case reports, but the methods ultimately did not endure. Endovascular treatment of acute cerebral ischemia was performed only rarely and in selected centers as part of individualized curative attempts. The Solitaire stent was originally developed to treat intracranial aneurysms through stent-assisted coil occlusion. The suggestion that this stent could also be used for intracranial thrombectomy was made as early as 2003 and was clinically confirmed in 2008. Releasing a Solitaire stent into an embolically occluded large cerebral artery, with an incubation time of approximately 3 minutes and slow retraction of the stent, has led to unprecedented success rates of thrombus removal and (sub)total recanalization in more than 90 % of patients. METHODS: This review article aimed to describe the steps in the development of endovascular stroke therapy, beginning with intra-arterial thrombolysis and early technical innovations leading to the eventual success of stent retriever thrombectomy. CONCLUSION: The potential for mechanical recanalization of acutely occluded large cerebral arteries could not be fully exploited until the advent of stent retriever thrombectomy. The entire concept of stroke treatment fundamentally changed after complete and rapid recanalization first became possible. Randomized controlled trials have shown superiority of stent retriever thrombectomy over IVT. An unparalleled boom in endovascular stroke therapy followed. KEY POINTS: · The history of endovascular stroke treatment was marked by setbacks in the first three decades.. · Stent retriever thrombectomy is the first procedure enabling recanalization of acute large intracranial artery occlusions in more than 90 % of patients.. · Stent retriever thrombectomy has transformed stroke care and neuroradiology in unprecedented ways.. · Further technical improvements will enable even faster, safer, complete recanalization in the near future.. · Further improvements in clinical outcomes will probably be determined by aspects beyond endovascular methods alone..

CLinical EValuation of WEB 17 device in intracranial aneuRysms (CLEVER): procedural, 30-day and 1-year safety results for ruptured and unruptured aneurysms.

BACKGROUND: Intrasaccular flow disruption is an endovascular approach for the treatment of wide-neck aneurysms and, more specifically, wide-neck bifurcation aneurysms, which are challenging to treat with previously developed technologies. The Woven EndoBridge (WEB) device has demonstrated its efficacy and safety, for both unruptured and ruptured aneurysms. METHODS: The CLEVER study was an observational, multicenter, prospective study conducted in 17 European investigational sites using the WEB 17 device, for the treatment of ruptured and unruptured aneurysms. The study objective was to provide safety and efficacy data on the WEB 17 device in the treatment of wide-neck bifurcation aneurysms. Imaging results were assessed independently by a Corelab and adverse events adjudicated by a Clinical Event Adjudicator. This analysis reports procedural results and safety at 30 days and 12 months. RESULTS: A total of 163 patients (mean age 58.1 years; 68.1% women) with 103 unruptured aneurysms and 60 ruptured aneurysms were enrolled. Most aneurysms were located on the anterior communicating artery (ACom) (37.4%) or the middle cerebral artery (MCA) bifurcation (30.1%). Aneurysm widths ranged from 2.0-9.2 mm, and the mean sac width was 5.0 mm. The WEB procedure was successfully completed in 163 patients (100%). At the 12-month follow-up, major stroke events occurred in 3 of 163 patients (1.8%), and no device-related mortality was observed. CONCLUSION: Endovascular treatment of ruptured and unruptured wide-neck bifurcation aneurysms using WEB 17 is safe, with a low complication rate and no device-related mortality. In particular, none of the ruptured aneurysms bled again up to 1 year of follow-up. TRIAL REGISTRATION NUMBER: NCT03844334.

Safety and effectiveness of the Woven EndoBridge (WEB) system for the treatment of wide necked bifurcation aneurysms: final 5 year results of the pivotal WEB Intra-saccular Therapy study (WEB-IT).

INTRODUCTION: The US Woven EndoBridge Intra-saccular Therapy (WEB-IT) study is a pivotal, prospective, single arm, investigational device exemption study to evaluate the safety and effectiveness of the WEB device for the treatment of wide neck bifurcation aneurysms (WNBAs). We present complete 5 year data for the cohort of 150 patients. METHODS: 150 patients with WNBAs were enrolled at 21 US and six international centers. Imaging from the index procedure, 6 month, 1 year, 3 year, and 5 year follow-up were reviewed by a core laboratory. Adverse events were reviewed and adjudicated by a clinical events adjudicator. RESULTS: 83 patients had 5 year follow-up imaging and 123 had clinical follow-up. No ruptured (0/9) or unruptured aneurysm (0/141) rebled or bled during follow-up. No new device or procedure related adverse events or serious adverse events were reported after 1 year. At 5 years, using the LOCF method, complete occlusion was observed in 58.1% and adequate occlusion in 87.2% of patients. For patients with both 1 year and 5 year occlusion statuses available, 76.8% (63/82) of aneurysms remained stable or improved with no retreatment. After 1 year, 18 aneurysms were retreated, 11 of which were adequately occluded at 1 year, and 15 of which were retreated in the absence of any deterioration in occlusion grade. CONCLUSIONS: Five year follow-up data from the WEB-IT study demonstrated that the WEB device was safe and effective when used in the treatment of WNBAs. Aneurysm occlusion rates achieved at 1 year follow-up were durable, with rates of progressive thrombosis far exceeding rates of recurrence over time.

A Systematic Literature Review and Meta-Analysis of the Treatment of Ruptured Intracranial Aneurysms with Hydrophilic Polymer and Phosphorylcholine-Coated Flow Diverters Under Single Antiplatelet Therapy.

OBJECTIVE: Flow diverters coated with antithrombogenic substances were recently introduced and have shown encouraging results in the preclinical setting. Our aim was to analyze their clinical application in patients with ruptured intracranial aneurysms using single antiplatelet therapy (SAPT). METHODS: We performed a PRISMA-compliant systematic review and meta-analysis covering 3 major data bases until March 2022.Two reviewers independently reviewed clinical studies for eligibility.Random-effects analysis of proportions was used to pool safety outcomes (hemorrhagic, thrombembolic, and overall complications). Studies were tested for publication bias and heterogeneity. RESULTS: Five studies reporting 43 patients with 46 aneurysms were identified. More than 1 stent was implanted in 16%, and additional coil embolization was performed in 53.8% of patients. SAPT with one of various acetylsalicylic acid regimens was used in 86%, altogether antiplatelet protocols were variable. The pooled risks of thromboembolic (23.9%; 95% confidence interval [CI], 9.6-47.9), hemorrhagic (9.4%; 95% CI, 3.6-22.6), and overall complications (28.3%; 95% CI, 12.4-52.5) were calculated in the absence of publication bias with low to moderate study heterogeneity measures. All complications occurred in patients under acetylsalicylic acid SAPT. Adequate aneurysm occlusion was described in 65.5% of patients.few retrospective observational studies with moderate heterogeneity, encompassing a limited number of patients treated with variable SAPT regimens. CONCLUSIONS: Flow diversion for ruptured aneurysms under SAPT with coated stents is feasible. Although the risk of hemorrhagic complications was low, thromboembolic complications occurred in a significant number of patients, all under ASA SAPT.

Aneurysm treatment with the Woven EndoBridge (WEB) device in the combined population of two prospective, multicenter series: 5-year follow-up.

BACKGROUND: Evaluating a new endovascular treatment for intracranial aneurysms must not only demonstrate short-term safety and efficacy, but also evaluate longer-term outcomes (eg, delayed complications, anatomical results, retreatment). The current analysis reports the 5-year clinical and anatomical results of Woven EndoBridge (WEB) treatment in two European combined trial populations (WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm Therapy) and WEBCAST-2). METHODS: All adverse events occurring between the procedure and 5-year follow-up were independently evaluated by an expert. Aneurysm occlusion was evaluated by an independent core laboratory using a three-grade scale: complete occlusion, neck remnant, and aneurysm remnant. In cases where data were not available at 5-year follow-up, the last observation carry forward (LOCF) method was used. RESULTS: The safety and efficacy populations comprised 100 patients and 95 aneurysms, respectively. No adverse event related to the device occurred after the procedure during the 5-year follow-up period. Mortality at 5 years was 7.0% (7/100 patients) including mortality related to the WEB (0/100, 0.0%), the procedure (1/100, 1.0%), and another condition (6/100, 6.0%). At 5 years, complete aneurysm occlusion was observed in 49/95 (51.6%) aneurysms, neck remnant in 25/95 (26.3%), and aneurysm remnant in 21/95 (22.1%). Retreatment rate at 5 years was 11.6% (11/95 aneurysms). CONCLUSIONS: This analysis conducted in a population of patients with wide-neck bifurcation aneurysms confirms WEB's safety profile. Additional evidence demonstrates good stability of aneurysm occlusion with adequate occlusion (complete occlusion or neck remnant) at 5 years in 77.9% of aneurysms with a low retreatment rate (11.6%). CLINICAL TRIAL REGISTRATION: WEBCAST and WEBCAST-2: Unique identifier: NCT01778322.

Coating (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) study. The first randomized controlled trial evaluating a coated flow diverter (p64 MW HPC): study design.

BACKGROUND: Due to its high efficacy, flow diversion is increasingly used in the management of unruptured and recanalized aneurysms. Because of the need for perioperative dual antiplatelet treatment (DAPT), flow diversion is not indicated for the treatment of ruptured aneurysms. To overcome this major limitation, surface modification-'coating'-of flow diverters has been developed to reduce platelet aggregation on the implanted device, reduce thromboembolic complications, and facilitate the use of coated flow diverter treatment in patients with single antiplatelet treatment (SAPT). COATING (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) is a prospective, randomized, multicenter trial that aims to determine whether the use of the coated flow diverter p64 MW HPC under SAPT is non-inferior (or even superior) to the use of the bare flow diverter p64 MW under DAPT in relation to thromboembolic and hemorrhagic complications. METHODS: Patients with unruptured or recanalized aneurysms for which endovascular treatment with a flow diverter is indicated will be enrolled and randomly assigned on a 1:1 ratio to one of two treatment groups: p64 MW HPC with SAPT or p64 MW with DAPT. RESULTS: The primary endpoint is the number of diffusion-weighted imaging lesions visualized via MRI assessed within 48 hours (±24 hours) of the index procedure. Secondary primary endpoints are comparing safety and efficacy in both arms. CONCLUSIONS: This randomized controlled trial is the first to directly compare safety and efficacy of coated flow diverters under SAPT with bare flow diverters under DAPT. TRIAL REGISTRATION NUMBER: http://clinicaltrials.gov/ - NCT04870047.

Will Coiling Survive through the Next Decade?

During the past three decades, neuroendovascular therapy has evolved from a focus on new disease concepts to revised treatment strategies and, ultimately, to versatile new technologies [...].

Mechanical thrombectomy for acute ischemic stroke in COVID-19 patients: multicenter experience in 111 cases.

BACKGROUND: Data on the frequency and outcome of mechanical thrombectomy (MT) for large vessel occlusion (LVO) in patients with COVID-19 is limited. Addressing this subject, we report our multicenter experience. METHODS: A retrospective cohort study was performed of consecutive acute stroke patients with COVID-19 infection treated with MT at 26 tertiary care centers between January 2020 and November 2021. Baseline demographics, angiographic outcome and clinical outcome evaluated by the modified Rankin Scale (mRS) at discharge and 90 days were noted. RESULTS: We identified 111 out of 11 365 (1%) patients with acute or subsided COVID-19 infection who underwent MT due to LVO. Cardioembolic events were the most common etiology for LVO (38.7%). Median baseline National Institutes of Health Stroke Scale score and Alberta Stroke Program Early CT Score were 16 (IQR 11.5-20) and 9 (IQR 7-10), respectively. Successful reperfusion (mTICI ≥2b) was achieved in 97/111 (87.4%) patients and 46/111 (41.4%) patients were reperfused completely. The procedure-related complication rate was 12.6% (14/111). Functional independence was achieved in 20/108 (18.5%) patients at discharge and 14/66 (21.2%) at 90 days follow-up. The in-hospital mortality rate was 30.6% (33/108). In the subgroup analysis, patients with severe acute COVID-19 infection requiring intubation had a mortality rate twice as high as patients with mild or moderate acute COVID-19 infection. Acute respiratory failure requiring ventilation and time interval from symptom onset to groin puncture were independent predictors for an unfavorable outcome in a logistic regression analysis. CONCLUSION: Our study showed a poor clinical outcome and high mortality, especially in patients with severe acute COVID-19 infection undergoing MT due to LVO.

Reconstructive endovascular treatment of basilar artery fenestration aneurysms: A multi-centre experience and literature review.

BACKGROUND: Data on outcome after endovascular treatment of basilar artery fenestration aneurysms (BAFAs) is limited. This study presents our multi-centre experience of BAFAs treated by different reconstructive techniques including coils, stent-assisted coiling (SAC), flow diversion and intra-saccular flow disruption with the Woven Endobridge (WEB). METHODS: Retrospective analysis of 38 BAFAs treated endovascularly between 2003 and 2020. The primary endpoint was complete aneurysm obliteration defined as Raymond-Roy occlusion classification (RROC) I on immediate and follow-up (FU) angiography. The secondary endpoints were procedure-related complications, rate of re-treatment, and clinical outcome. RESULTS: Endovascular treatment was feasible in 36/38 aneurysms (95%). The most frequent strategy was coiling (21/36, 58%), followed by SAC (7/36, 19%), WEB embolization (6/36, 17%) and flow diversion (2/36, 6%). A successful aneurysm occlusion (defined as RROC 1 and 2) on the final angiogram was achieved in 30/36 (83%) aneurysms including all patients presenting with baseline subarachnoid haemorrhage and 25/36 (69%) were occluded completely. Complete occlusion (RROC 1) was more frequently achieved in ruptured BAFAs (15/25, 60% v. 2/11, 18%; p = 0.031). Procedure-related complications occurred in 3/36 (8%) aneurysms. Re-treatment was executed in 12/36 (33%) aneurysms. After a median angiography FU of 38 months, 30/31 (97%) BAFAs were occluded successfully and 25/31 (81%) showed complete occlusion. CONCLUSION: Reconstructive endovascular treatment of BAFAs is technically feasible with a good safety profile. Although in some cases re-treatment was necessary, a high rate of final aneurysm occlusion was achieved.

Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device.

BACKGROUND: The use of flow diversion to treat intracranial aneurysms has increased in recent years. OBJECTIVE: To assess the safety and angiographic efficacy of the p64 flow modulation device. METHODS: Diversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3-6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography. RESULTS: A total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10). CONCLUSIONS: Diversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

Flow diversion for internal carotid artery aneurysms with compressive neuro-ophthalmologic symptoms: clinical and anatomical results in an international multicenter study.

BACKGROUND: Scientific data on the safety and efficacy of flow diverter stents (FDS) for the treatment of unruptured internal carotid artery (ICA) aneurysms with compressive neuro-ophthalmological symptoms are scarce. We studied this subject in a retrospective international multicenter series, pooling data of 9 tertiary care neurointerventional departments. OBJECTIVE: To investigate, in a retrospective, multicentric cohort of patients presenting with visual or oculomotor symptoms attributed to a compressive carotid artery in an unruptured intracranial aneurysm, the safety and efficacy profiles of FDS, by analyzing neuro-opthalmologic symptom evolution following FDS placement, complications, and aneurysm obliteration rates. METHODS: All patients treated since 2015 with a FDS for an unruptured aneurysm of the ICA with signs of compressive cranial nerve symptoms (CN II, III, IV, VI) were included. RESULTS: We treated 55 patients with 55 aneurysms; 21 (38.2%) patients had oculomotor and 15 (27.3%) visual symptoms only; 19 (34.5%) presented with a combination of both. Treatment-related morbidity/mortality occurred in 7.2% and 3.6%, respectively. At last imaging follow-up (13.1±10.5 months) rates of complete aneurysm occlusion, neck remnant, and aneurysm remnant were 72%, 14%, and 14%, respectively. At last clinical follow-up after 13±10.5 months, 19/51 (37.3%) patients had recovered completely and 18/51 (35.3%) had recovered at least partially from their neuro-ophthalmological symptoms. In multivariable models, a longer delay between symptom onset and treatment was associated with higher odds for incomplete recovery and lower odds for any improvement (aOR 1.03 (95% CI 1.01 to 1.07), p=0.047 and 0.04 (0-0.81), p=0.020). Incomplete recovery was independently associated with older age and fusiform aneurysms. CONCLUSION: FDS are effective to treat patients with compressive aneurysms of the ICA causing neuro-ophthalmological symptoms, especially when treatment is initiated early after symptom onset, and aneurysm occlusion is adequate. However, serious complications are not rare.

Aneurysm treatment with WEB in the cumulative population of two prospective, multicenter series: 3-year follow-up.

BACKGROUND: WEB treatment is an endovascular approach for wide-neck bifurcation aneurysms that has demonstrated high safety and good efficacy in mid-term follow-up. While evaluating safety in the long term is important to determine if delayed adverse events occur affecting late morbidity and mortality, the most important point to evaluate is the long-term stability of aneurysm occlusion. The current analysis reports the 3-year clinical and anatomical results of WEB treatment in the combined population of two European trials (WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm Therapy) and WEBCAST-2). METHODS: Aneurysm occlusion was evaluated using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant. RESULTS: The safety population comprised 79 patients. The efficacy population comprised 61 aneurysms. Aneurysm locations were middle cerebral artery in 32/61 aneurysms (52.5%), anterior communicating artery in 13/61 (21.3%), basilar artery in 9/61 (14.8%), and internal carotid artery terminus in 7/61 (11.5%). No adverse events related to the device or procedure occurred between 2 and 3 years. At 3 years, complete occlusion was observed in 31/61 (50.8%) aneurysms, neck remnant in 20/61 (32.8%), and aneurysm remnant in 10/61 (16.4%). Between 1 year and 3 years, aneurysm occlusion was improved or stable in 53/61 (86.9%) aneurysms and worsened in 8/61 (13.1%). Worsening was mostly from complete occlusion to neck remnant in 6/61 (9.8%) aneurysms. The retreatment rate at 3 years was 11.4%. CONCLUSIONS: This analysis confirms the high safety profile of WEB. Moreover, evidence demonstrates the great stability of aneurysm occlusion with adequate occlusion (complete occlusion or neck remnant) in 83.6% of aneurysms. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. WEBCAST and WEBCAST-2: Unique identifier: NCT01778322.

Aneurysm Treatment With Woven EndoBridge in the Cumulative Population of 3 Prospective, Multicenter Series: 2-Year Follow-Up.

BACKGROUND: Woven EndoBridge (WEB; Sequent Medical) treatment is an innovative endovascular approach for treatment of wide-neck bifurcation aneurysms. Initial studies have shown high safety with good efficacy at short term confirmed by trials conducted in United States (WEB-Intrasaccular Therapy) and in Europe (WEB Clinical Assessment of Intrasaccular Aneurysm Therapy [WEBCAST], French Observatory, and WEBCAST-2). OBJECTIVE: To report the 2-yr clinical and anatomical results of WEB treatment in the combined population of 3 European trials. METHODS: In a French Observatory, 2-yr clinical and anatomical data were collected. In WEBCAST and WEBCAST-2, 2-yr follow-up was optional, and data were collected when follow-up was performed. Aneurysm occlusion was evaluated using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant. RESULTS: The population for safety was 138/168 patients (82.1%), including 89 females (64.5%), with mean age of 55.5 ± 10.2 yr. The population for efficacy was 121/169 aneurysms (71.6%). Aneurysm locations were middle cerebral artery in 65/121 aneurysms (53.7%), anterior-communicating artery in 25/121 (20.7%), basilar artery in 17/121 (14.0%), and internal carotid artery terminus in 14/121 (11.6%). No clinically relevant adverse events occurred between years 1 and 2. At 2 yr, complete occlusion was observed in 62/121 (51.2%) aneurysms, neck remnant in 36/121 (29.8%) aneurysms, and aneurysm remnant in 23/121 (19.0%) aneurysms. The global retreatment rate at 2 yr was 9.3%. CONCLUSION: This analysis confirms the high safety profile of WEB treatment at 2 yr. Aneurysm occlusion is generally stable at 2 yr, and the retreatment rate between 1 yr and 2 yr is low (2.0%).

Induction of extracranial arteriogenesis by an arteriovenous fistula in a pig model.

BACKGROUND AND AIMS: Arteriogenesis, the positive outward remodeling and growth of pre-existent collateral vessels, holds potential as a novel treatment for ischemic vascular disease. An extracranial arteriogenesis model in a pig will allow us to study molecular changes in a complex arteriolar network in a more clinically relevant large-animal model. To increase fluid shear stress in the brain, an experimental carotid arteriovenous fistula (AVF model) in minipigs was established, providing high flow through the extracranial rete mirabile. The aim of the study was to examine whether creation of a carotid AVF can induce extracranial arteriogenesis in the pig. METHODS: Angiography was performed to demonstrate blood flow diversion. Animals were sacrificed after 0, 3 and 14 days post-surgery and both retia mirabilia were removed. Immunohistochemical analysis was performed to analyze cell proliferation and accumulation of mononuclear cells in the vessel wall. RESULTS: After 3 days of high-flow conditions, increases in vascular cell proliferation (approximately 1.5-fold; p = 0.143) and monocyte invasion (approximately 6-fold; p = 0.057) were observed when compared to animals sacrificed immediately after AVF formation. Quantitative PCR (RT-qPCR) analysis from rete mirabile tissue samples 3 days post-surgery revealed that monocyte chemoattractant protein (MCP)-1 and tissue inhibitor of metalloproteinases (TIMP)-1 were highly upregulated. Expression of the pro-arteriogenic marker, CD44, reached maximum expression level 14 days post-surgery. CONCLUSIONS: In response to high levels of shear stress produced in the pig AVF model, the onset of the arteriogenic process can be induced. This was demonstrated by enhanced cell proliferation, monocyte invasion and vascular remodeling.

Safety and efficacy of aneurysm treatment with WEB in the cumulative population of three prospective, multicenter series.

BACKGROUND: Flow disruption with the WEB is an innovative endovascular approach for treatment of wide-neck bifurcation aneurysms. Initial studies have shown a low complication rate with good efficacy. PURPOSE: To report clinical and anatomical results of the WEB treatment in the cumulative population of three Good Clinical Practice (GCP) studies: WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm), French Observatory, and WEBCAST-2. METHODS: WEBCAST, French Observatory, and WEBCAST-2 are single-arm, prospective, multicenter, GCP studies dedicated to the evaluation of WEB treatment. Clinical data were independently evaluated. Postoperative and 1-year aneurysm occlusion was independently evaluated using the 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant. RESULTS: The cumulative population comprised 168 patients with 169 aneurysms, including 112 female subjects (66.7%). The patients' ages ranged between 27 and 77 years (mean 55.5±10.2 years). Aneurysm locations were middle cerebral artery in 86/169 aneurysms (50.9%), anterior communicating artery in 36/169 (21.3%), basilar artery in 30/169 (17.8%), and internal carotid artery terminus in 17/169 (10.1%). The aneurysm was ruptured in 14/169 (8.3%). There was no mortality at 1 month and procedure/device-related morbidity was 1.2% (2/168). At 1 year, complete aneurysm occlusion was observed in 81/153 aneurysms (52.9%), neck remnant in 40/153 aneurysms (26.1%), and aneurysm remnant in 32/153 aneurysms (20.9%). Re-treatment was carried out in 6.9%. CONCLUSIONS: This series is at the moment the largest prospective, multicenter, GCP series of patients with aneurysms treated with WEB. It shows the high safety and good mid-term efficacy of this treatment. CLINICAL TRIAL REGISTRATION: French Observatory: Unique identifier (NCT18069); WEBCAST and WEBCAST-2: Unique identifier (NCT01778322).