Weighing in on the Off-Label Use: Initial Experience of Neuroform EZ Stenting for Intracranial Arterial Stenosis in 45 Patients

Angiographic Pattern of M1 Stenosis Predicts Territorial Stroke in Patients Receiving Aggressive Medication without Stenting

OBJECTIVE

To evaluate the relationship between different angiographic patterns of middle cerebral artery M1 segment stenosis and related territorial stroke in patients receiving aggressive medical treatment without stenting.

METHODS

We retrospectively reviewed our patient registry database to identify ICAS patients diagnosed by digital subtraction angiography between January 2017 and December 2020 and identified 3 different angiographic patterns (normal, shift, and dilation) in 124 patients with M1 stenosis. The association between these patterns and recurrent ischemic stroke in the M1 territory was analyzed.

RESULTS

The rates of recurrent M1 territorial stroke and transient ischemic attack in the normal group, shift group, dilation group and shift-dilation group were 34.5%, 35.0%, 78.3%, and 44.4% respectively. In patients with the shift pattern, the rate of recurrent stroke is significantly higher at a deflection angle ≥9.32° than at a deflection angle <9.32°(P < 0.05). In patients with dilation pattern, the rate of recurrent stroke is significantly higher than patients with non-dilation pattern (72.3% vs. 36.8%, P < 0.05).

CONCLUSIONS

Angiographic patterns of M1 stenosis may predict recurrent territorial strokes, thus providing a surrogate marker to identify high-risk patients for potential endovascular treatment.

Short-term efficacy of stenting as a rescue therapy for acute atherosclerotic occlusion in anterior cerebral circulation

Purpose

The study aimed to explore the efficacy and safety of the Neuroform EZ stent in treating acute anterior circulation large artery occlusion.

Methods

The clinical data of 42 consecutive patients with acute anterior circulation large atherosclerotic occlusion who were treated with the Neuroform EZ stent from January 2018 to August 2019 in our stroke care center, including baseline characteristics, images, therapeutic condition, and follow-up data were retrospectively analyzed.

Results

There were 42 mechanical thrombectomy (MT) failure cases of intracranial atherosclerotic stenosis with rescue Neuroform EZ stent implantation, of which 78.6% (33/42) had a good prognosis and 88.1% (37/42) showed no re-stenosis at follow-up. The average time from puncture to recanalization is 79.50 ± 14.19 min. The successful rate of intraoperative stent release is 97.6%, while there is one case of stent displacement, three cases of thrombus escape, and six cases of hemorrhage.

Conclusion

Rescue therapy of the Neuroform EZ stent for acute anterior circulation large atherosclerotic occlusion can archive good short-term imaging and clinical results, while long-term follow-up is still needed to verify.

Optional or optimal? off-label stenting for intracranial atherosclerotic stenosis: A scoping review

BACKGROUND

Intracranial atherosclerotic stenosis is a major cause of ischemic stroke. In addition to the Wingspan stent system, several self-expanding stents have been used off-label to treat intracranial atherosclerotic stenosis lesions. The purpose of this review is to assess the existing data on the off-label use of self-expanding stents in intracranial atherosclerotic stenosis, to highlight methodological limitations in current study designs, and thus providing strategies and precautions for clinical practice.

METHODS

The PubMed, EMBASE, and the Cochrane Library databases were systematically searched for relevant articles published up to April 2022. In addition to the meta analysis of Enterprise, Neuroform EZ and closed cell stent respectively, we used a narrative synthesis to summarize and discuss the appropriate strategies and precautions for the use of each stent.

RESULTS

We identified 17 studies (1091 patients with 1124 lesions) reporting 6 types of off-label self-expanding stents. The most common endpoints reported were incidence of short-term complications (range: 0-15.8%, median: 3.8%), long-term complications (range: 0-12.0%, median: 0%). Potential risks include infeasibility of stenting hard lesions or tortuous vessels, stent migration, and in-stent thrombosis. Less is known about the conditions that are appropriate for an optimal stent (e.g., open-cell, close-cell, hybrid cell). There was considerable heterogeneity across studies with regards to study populations and study designs.

CONCLUSIONS

The potential risks and benefits should be carefully considered when using off-label stents for intracranial atherosclerotic stenosis, particularly given the current evidence power. As a potential option for the Wingspan stent, based on device's approval only, a tailored approach with lesion-specific devices could be beneficial in certain patients.

Intracranial angioplasty with a self-expandable stent for intracranial atherosclerotic stenosis: Systematic review and meta-analysis

Background

Intracranial angioplasty with a self-expandable stent (SES) is an important endovascular therapy for symptomatic intracranial arterial stenosis. We sought to update the evaluation of the perioperative safety and long-term outcomes of self-expandable stent for the treatment of symptomatic intracranial arterial stenosis.

Methods

We comprehensively searched the published literature from each database through Sept 16, 2022, for the PubMed, EMBASE, Web of Science, Cochrane, and Clinical Trials databases. The characteristics of the studies and patients, perioperative complications, and long-term outcomes were extracted. The pooled outcomes and 95% confidence intervals (CIs) were estimated by Stata Statistical Software 14.0.

Results

A total of 4,632 patients from 58 studies were included. The pooled rate of perioperative stroke or death was 6.32% (95% CI 5.04-7.72%); ischemic stroke beyond 30 days through 1 year was 2.72% (95% CI 1.41-4.38%). Perioperative complications differed between the 2014-2022 and 2005-2013 subgroups, as did long-term outcomes between the off-label SES and Wingspan subgroups.

Conclusion

The perioperative complications of intracranial angioplasty with SES have been reduced, but the risk of perioperative stroke or death is still higher than that of aggressive medical therapy, and additional studies are needed to determine whether it has better long-term outcomes than aggressive medical therapy. Perioperative complications varied between the 2014-2022 and 2005-2013 subgroups, as did long-term outcomes between the off-label SES and Wingspan subgroups. Given the high level of heterogeneity observed between the included studies, these results should be interpreted with caution and additional studies are needed.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022316066.

Neuroform EZ Stents for Hepatic Artery Stenosis After Liver Transplantation: A Single-Center Preliminary Report

PURPOSE

This preliminary study evaluated the safety and effectiveness for off-label use of Neuroform EZ (NEZ) stents in the revascularization of hepatic artery stenosis (HAS) after orthotopic liver transplantation (OLT).

MATERIALS AND METHODS

Nine of 489 (5%) OLTs with HAS were managed with NEZ stents between September 2016 and July 2021. Stenting outcomes were evaluated based on the technical success rate, procedure-related complications, and primary patency.

RESULTS

A total of 10 NEZ stents (4.5 mm × 3 cm, n = 6; 4 mm × 3 cm, n = 4) were successfully deployed in 9 torturous hepatic arteries and in 1 relatively straight artery without any procedure-related complications. Combined thrombolysis (n = 3) and balloon angioplasty (n = 6) was performed. The median duration of follow-up was 438 days (range, 120-1126 days). Asymptomatic re-stenoses were detected in 2 stents on days 60 and 433 after stenting. A Kaplan-Meier curve predicted cumulative primary stent patencies at 1, 2, and 3 years of 90%, 75%, and 75%, respectively.

CONCLUSION

NEZ stents can be safely used to treat HAS after OLT with high technical success and favorable primary patency.

Update on Clinical Management with Neurovascular Stents

Endovascular stenting has continued to evolve given the new trials. Several new stents have recently been developed to address specific purposes. In this focused review, we discuss the concepts of neurointerventional stents and address the clinical implications. Furthermore, each type of stent is discussed with supporting evidence for clinical utility. In the final component, we argue for continued development and utilization.

The safety and efficacy of the Neuroform EZ stent for the treatment of symptomatic atherosclerotic stenosis in the middle cerebral artery

OBJECTIVE

To evaluate the safety and efficacy of Neuroform EZ stent placement for patients with symptomatic atherosclerotic stenosis of the middle cerebral artery (MCA).

METHOD

We retrospectively reviewed the clinical data of 70 patients (36 males and 34 females; mean age: 62.5 ± 1.25 years) with symptomatic atherosclerotic stenosis of the MCA who underwent Neuroform EZ stent insertion between January 2018 and June 2020. We reviewed the clinical data of each patient so that we could evaluate outcomes and angiographic findings at follow-up.

RESULTS

The technical success rate for the 70 patients was 100%. The mean rate of stenosis improved from 82.6 ± 6.5% (pre-stenting) to 21.11 ± 2.6% (post-stenting). During the post-stenting follow-up period, the 1-year frequencies of stroke, transient ischemic attack, and death, were all 0%. 42 patients were reviewed in hospital by DSA or CTA. Of the patients undergoing DSA or CTA review, four patients were found to have in-stent restenosis.

CONCLUSION

Our analysis indicates that the Neuroform EZ stent represents a valuable endovascular treatment option for patients with severe stenosis of the MCA. Additional studies are now needed to evaluate the long-term outcomes arising from the use of this technique.

Rescue Endovascular Treatment for Emergent Large Vessel Occlusion With Underlying Intracranial Atherosclerosis: Current State and Future Directions

Intracranial atherosclerosis (ICAS) is one of the most common causes of stroke worldwide and is associated with high risk of stroke recurrence. While the most common clinical presentation is acute–subacute transient ischemic attack or ischemic stroke, occasionally, patients with underlying ICAS present with acute occlusion of the affected vessel. Diagnosis and endovascular management of ICAS-related emergent large vessel occlusion (ELVO) can be challenging. Herein, we review the current evidence supporting endovascular management of ICAS-related ELVO and discuss future directions.

Application of High-Resolution Flat Detector Computed Tomography in Stent Implantation for Intracranial Atherosclerotic Stenosis

Objective

To evaluate the utility of high-resolution flat-detector computed tomography (HR-FDCT) compared with conventional flat-detector computed tomography (FDCT) for stent placement in symptomatic intracranial atherosclerotic stenosis (ICAS).

Methods

We retrospectively reviewed the clinical data of 116 patients with symptomatic ICAS who underwent stent implantation. Images were acquired using conventional FDCT [voxel size = 0.43 mm (isotropic)] and HR-FDCT [voxel size = 0.15 mm (isotropic)]. Immediately after stent deployment, dual-volume three-dimensional (3D) fusion images were obtained from 3D digital subtraction angiography (DSA) and HR-FDCT. The image quality for stent visualization was graded from 0 to 2 (0: not able to assess; 1: limited, but able to assess; 2: clear visualization), and the stent-expansion status (“full,” “under-expanded” or “poor apposition”) was recorded.

Results

A total of 116 patients with symptomatic ICAS were treated successfully using 116 stents (58 Neuroform^TM EZ, 42 Enterprise^TM, and 16 Apollo^TM). The mean pre-stent stenosis was 80.5 ± 6.4%, which improved to 20.8 ± 6.9% after stenting. Compared with FDCT, HR-FDCT improved visualization of the fine structures of the stent to improve the image quality that significantly (mean score: 1.63 ± 0.60 vs. 0.41 ± 0.59, P < 0.001). In 19 patients, stent under-expansion (n = 11) or poor apposition (n = 8) was identified by HR-FDCT but not by conventional FDCT. After balloon dilatation, stent malapposition was shown to have improved on HR-FDCT. None of the 19 patients with stent malapposition experienced short-term complications during hospitalization or had in-stent stenosis at 6-month follow-up.

Conclusion

High-resolution flat-detector computed tomography (HR-FDCT) improves visualization of the fine structures of intracranial stents deployed for symptomatic ICAS compared with that visualized using conventional FDCT. High-resolution flat-detector computed tomography improves assessment of stent deployment and could reduce the risk of complications.

Incidence and Risk Factors of In-Stent Restenosis for Symptomatic Intracranial Atherosclerotic Stenosis: A Systematic Review and Meta-Analysis

BACKGROUND

In-stent restenosis affects long-term outcome in patients with intracranial atherosclerotic stenosis.

PURPOSE

The aim of this meta-analysis was to evaluate the incidence and risk factors of in-stent restenosis.

DATA SOURCES

All literature that reported in-stent restenosis was searched on PubMed, Ovid EMBASE and Ovid MEDLINE data bases.

STUDY SELECTION

Original articles about stents for symptomatic intracranial atherosclerotic stenosis were selected.

DATA ANALYSIS

Meta-analysis was conducted to derive the pooled in-stent restenosis using a random-effects model. Meta-regression was performed to explore the risk factors predisposing to in-stent restenosis.

DATA SYNTHESIS

In total, 51 studies with 5043 patients were included. The pooled incidence rate of in-stent restenosis was 14.8% (95% CI, 11.9%-17.9%). Among the lesions with in-stent restenosis, 28.8% of them led to (95% CI, 22.0%-36.0%) related neurologic symptoms. The series in the United States had a higher in-stent restenosis rate (27.0%; 95% CI, 20.6%-33.9%) compared with those from Asia (13.6%; 95% CI, 10.3%-17.2%) and other regions as a whole (7.6%; 95% CI, 1.1%-18.1%) (P < .01). Multiregression analysis revealed that younger patient age was related to high in-stent restenosis rates (P = .019), and vertebrobasilar junction location (P = .010) and low residual stenosis (P = .018) were 2 independent risk factors for symptomatic in-stent restenosis rate.

LIMITATIONS

The heterogeneity of most outcomes was high.

CONCLUSIONS

Our study showed promising results of in-stent restenosis for symptomatic atherosclerotic stenosis. Studies are needed to further expatiate on the mechanisms by which younger patient age, vertebrobasilar junction location, and low residual stenosis could increase in-stent restenosis and symptomatic in-stent restenosis, respectively.

A novel technique for stenting in cases of refractory intracranial stenosis

Endovascular management of intracranial stenosis is one of the most controversial subjects in neurointervention. Previous level 1 evidence shows superiority of medical management but more recent studies have shown improved outcomes in selective patients. We describe a case demonstrating a new method for stenting of intracranial stenosis using a single system with Coyote angioplasty balloon (Boston Scientific) and the Atlas stent (Stryker).

Thirty-Day Outcomes of the Enterprise Stent in Treating Hypoperfusion of Symptomatic Intracranial Stenosis

OBJECTIVE

To evaluate the 30-day outcomes of using the Enterprise stent to treat patients with hypoperfusion of symptomatic severe intracranial stenosis.

METHODS

Patients with symptomatic severe intracranial stenosis (70%-99%) who underwent Enterprise stent intervention between August 2014 and November 2018 were retrospectively analyzed. The 30-day primary outcomes included the success rate of stenting and the incidence of complications, including ischemic stroke, cerebral hemorrhage, and death. The 30-day complication rates of patients with different lesion locations and classifications of Mori morphology were compared.

RESULTS

Sixty-eight patients were treated using 70 Enterprise stents. The success rate was 100%. The 30-day complication rate was 4.4%. The rates of ischemic stroke, cerebral hemorrhage, and death were 1.5%, 2.9%, and 0%, respectively. No significant difference was found in the 30-day complication rate between patients with different lesion locations and classifications of Mori morphology (P > 0.05).

CONCLUSION

Enterprise stents were relatively safe in treating patients with hypoperfusion of symptomatic severe intracranial stenosis.