Contemporary Results of Carotid Artery Stenting Using Low-Profile Dual-Metal Layer Nitinol Micromesh Stents in Relation to Single-Layer Carotid Stents

[Stenting of the extracranial internal carotid artery]

The treatment of patients with stenosis of the internal carotid artery (ICA) is based on established guidelines, which includes both surgical and endovascular treatment options; however, the most recent advances, including the emergence of new endovascular treatment methods and techniques, combined with more recent clinical results, throw a new light on the optimal selection and treatment of patients in the current practice. This article deals with the most recent advances in the field of stenting of the extracranial internal carotid artery.

Clinical results of 30 consecutive patients of carotid artery stenosis treated with CASPER stent placement: 1-year follow-up and in-stent findings on intravascular ultrasound examination immediately and 6 months after treatment

BACKGROUND

The CASPER stent is expected to reduce periprocedural ischemic complications, but there is concern about restenosis in the early period. One-year follow-up results of CASPER stenting and findings on intravascular ultrasound (IVUS) immediately and 6 months after treatment are evaluated.

METHODS

Thirty consecutive patients were treated with CASPER stents for carotid artery stenosis. IVUS was performed immediately after stenting, and MRI and carotid ultrasonography were performed the next day, at 1 week, at 2 weeks, and then every 3 months. One-year follow-up results were evaluated. Twenty-five patients underwent follow-up angiography and IVUS after 6 months and their findings were investigated.

RESULTS

All patients were treated without complications during the intraoperative and periprocedural periods. After 6 months, all 25 patients with follow-up angiography and IVUS showed various degrees of intimal formation on IVUS and 8 of them had ≥50% stenosis on angiography. Three of the 30 patients required retreatment within 6 months because of severe restenosis. In these patients, the inner layer of the stent was deformed toward the inside due to intimal hyperplasia on follow-up IVUS, and there was dissociation between the inner and outer layers. All but the 3 of 30 patients with 1-year follow-up did not lead to symptomatic cerebrovascular events or retreatment.

CONCLUSIONS

The CASPER stent appears to be effective for preventing periprocedural ischemic complications. IVUS showed various degrees of intimal formation within 6 months after treatment, and it is possible that the CASPER stent is structurally prone to intimal formation or hyperplasia.

Carotid Artery Stenting With Double-Layer Stent: A Systematic Review and Meta-Analysis

BACKGROUND

Carotid artery stenting (CAS) in the treatment of significant stenosis is a cause of stroke due to both plaque prolapse and cerebral embolization. New types of stents with a double-layer structure have been designed to minimize plaque prolapse and embolization; these double-layer stents (DLSs) should be able to reduce the stroke risk; however, definite data on their performance are scarce in the literature.

METHODS

A systematic search was performed through PubMed, Scopus, and Cochrane Library, according to PRISMA guidelines; all studies on CAS with DLS (Roadsaver/Casper or CGuard) up to January 1, 2022, with a cohort of at least 20 patients were considered eligible. The present meta-analysis was approved and registered on PROSPERO register (CRD42022297512). Patients with tandem lesions or complete carotid occlusion were excluded from the study. The 30-day stroke rate after CAS was analyzed evaluating the preoperative symptomatic status and DLS occlusion. The estimated pooled rate of events was calculated by random effect model and moderators were evaluated.

RESULTS

A total of 14 studies were included in the meta-analysis for a total of 1955 patients. The estimated overall (95% confidence interval [CI]) stroke rate was 1.4% (0.9%-2.2%, I2 = 0%), which was not influenced by the type of DLS used: CGuard 0.8% (0.4%-1.8%, I2 = 0%) versus Roadsaver/Casper 1.5% (0.7%-3.2%, I2 = 0%), p=0.30. The 30-day estimated stroke rate was 1.5% (0.8%-2.9%, I2 = 0%) in asymptomatic and 1.9% (1.0%-3.6%, I2 = 0%) in symptomatic patients, with no influence by moderators. The 30-day DLS occlusion rate was 0.8% (0.4%-1.8%, I2 = 0%). The publication bias assessment identified asymmetry in the asymptomatic populations.

CONCLUSION

The overall 30-day stroke rate in CAS with DLS is low (1.4%), with similar results in symptomatic and asymptomatic patients. Acute occlusion of DLS is rare (0.8%). Further studies are necessary to reduce the publication bias for asymptomatic patients.

CLINICAL IMPACT

CAS with DLS is associated to a low rate of 30-day stroke in both symptomatic (1.9%) and asymptomatic (1.5%) patients. The type of DLS (CGuard or Roadsaver/Casper) did not affect the 30-day stroke rate.

Navigating complexity with low-crossing profile dual-layer micromesh carotid stent: implications for contemporary carotid artery stenting outcomes (ROADSAVER study insights)

BACKGROUND

The safety and efficacy of carotid artery stenting (CAS) can be affected by certain technical and anatomical factors. However, it is not known whether the use of a dual-layer micromesh stent (DLMS) with a low-crossing profile could reduce the risks associated with complex vascular anatomies during CAS.

METHODS

This study involved 1965 asymptomatic or symptomatic carotid artery stenosis patients who received the Roadsaver DLMS during CAS, as part of a prospective, multicenter observational ROADSAVER study, conducted from January 2018 to February 2021. The primary outcome was the 30-day rate of major adverse events (MAE; i.e. any death or stroke) after CAS. Procedural details and outcomes were compared between patients with complex anatomical features and those without.

RESULTS

One or more complex anatomical characteristics were identified in 1639 (83.4%) patents. Patients with complex anatomies were older and had a higher prevalence of arterial hypertension, cardiovascular disease, and prior stroke. Between patients with or without complex anatomical features, no significant differences were found either in procedural techniques, or in 30-day MAE (age-adjusted odds ratio (95% CI) for complexities vs. no complexities: 0.76 (0.35, 1.66); p=0.4905) and any stroke (age-adjusted odds ratio (95% CI) for complexities vs. no complexities: 0.89 (0.37, 2.17); p=0.8032) incidence. Furthermore, neither the presence of specific types of anatomic complexity nor their number (per patient) markedly influenced the 30-day MAE and any stroke incidence.

CONCLUSIONS

In this real-world cohort of patients undergoing CAS with the Roadsaver DLMS, no significant difference in the occurrence of 30-day MAE and any stroke was observed between patients with or without high-risk anatomical features.

CIRSE Standards of Practice on Carotid Artery Stenting

BACKGROUND

Carotid artery stenting has been used effectively to treat internal carotid artery stenosis since 1989 (Mathias et al. in World J Surg. 25(3):328-34, 2001), with refined and expanded techniques and tools presently delivering outstanding results in percutaneous endoluminal treatment of carotid artery stenosis.

PURPOSE

This CIRSE Standards of Practice document is directed at interventional radiologists and details the guidelines for carotid artery stenting, as well as the different implementation techniques. In addition to updating all previously published material on the different clinical indications, it will provide all technical details reflective of European practice for carotid artery stenting. CIRSE Standards of Practice documents do not aim to implement a standard of clinical patient care, but rather to provide a realistic strategy and best practices for the execution of this procedure.

METHODS

The writing group, which was established by the CIRSE Standards of Practice Committee, consisted of five clinicians with internationally recognised expertise in carotid artery stenting procedures. The writing group reviewed existing literature on carotid artery stenting procedures, performing a pragmatic evidence search using PubMed to select relevant publications in the English language from 2006 to 2022.

RESULTS

Carotid artery stenting has an established role in the management of internal carotid artery stenosis; this Standards of Practice document provides up-to-date recommendations for its safe performance.

Dual-layered stents reduce cerebral embolism compared with first-generation stents during carotid stenting of high lipid core plaque lesions

BACKGROUND

Periprocedural lipid core plaque (LCP) has been detected in carotid arteries assessed by catheter-based near-infrared spectroscopy (NIRS). High LCP is associated with cerebral embolism after carotid artery stenting (CAS) using a first-generation stent. We aimed to evaluate whether dual-layered stents reduce embolic infarcts in patients with high LCP and change of lipid signal as assessed by NIRS during CAS.

METHODS

Participants comprised 210 consecutive patients undergoing CAS. The study was divided into two distinct periods, with first-generation closed-cell stents used in the earlier period and dual-layered stents used in the later period. NIRS was performed at baseline, after stent implantation, and after balloon post-dilatation to analyze maximal lipid core burden index at minimal luminal area (max-LCBIMLA).

RESULTS

The ipsilateral cerebral embolism rate was significantly lower with dual-layered stents (9%) than with first-generation stents (33%, p<0.001), particularly with highly lipidic lesions (12% vs 60%, p<0.001). On multivariate logistic regression analysis, high LCP and first-generation stent usage were factors related to ipsilateral cerebral embolism (both p<0.001; OR 8.28 (95% CI 3.49 to 19.64) and OR 8.07 (95% CI 2.33 to 27.93), respectively). Max-LCBIMLA decreased significantly after stenting in both groups (both p<0.01) and max-LCBIMLA after balloon post-dilatation was significantly lower with dual-layered stents (22.4±65.6) than with first-generation stents (124.2±208.2; p=0.006).

CONCLUSIONS

Dual-layered stents reduce embolic infarcts in patients with highly lipidic plaque lesions as assessed by NIRS who undergo CAS. Dual-layered stents significantly reduced NIRS-derived lipid signals after stenting.

Dual- vs single-layer stents for endovascular treatment of symptomatic and asymptomatic internal carotid artery stenosis

BACKGROUNDS

Plaque protrusion is a common event among carotid artery stenting (CAS) patients and increases ischemic complication risk. Dual-layer stents (DLS) with micromesh technology may offer greater plaque protection compared to single-layer stents (SLS), but few data are available. The aim of the study is to compare clinical outcomes at 12 months for asymptomatic and symptomatic patients treated for primary CAS with DLS or SLS in a high-volume center.

METHODS

A retrospective analysis of consecutive symptomatic and asymptomatic patients treated with primary CAS for internal carotid artery (ICA) stenosis, with either DLS or SLS between 2015 and 2019, was performed. Primary endpoints included rates of ipsilateral transient ischemic attacks (TIA)/stroke and death within 1-year from CAS. Secondary endpoints included patency rates and survival according to stent type.

RESULTS

Of the 301 patients who met inclusion criteria (74.8 % male; 73.6 mean age ± 8.7 years), most patients were asymptomatic (77.4 %). Among all patients DLS was most frequently deployed (66 %); also, among asymptomatic (62 %) and symptomatic patients (81 %), p < 0.01. Symptomatic patients had less comorbidities and severe disease than asymptomatic patients. Six peri-operative strokes were recorded and, within 1 year, 2 additional strokes were registered among symptomatic patients treated with SLS. No post-operative strokes were encountered in the DLS group (p = 0.04) among symptomatic patients. Higher rates of TIA were observed among asymptomatic patients treated with DLS compared to SLS while rates of TIA were reduced among symptomatic patients treated with DLS. There were no differences in patency rates for DLS and SLS in symptomatic and asymptomatic patients. Primary patency was similar among DLS stent types but differed among SLS stent types (p = 0.01). At a mean follow-up of 27 months ±17.6, survival was comparable between DLS and SLS groups (p = 0.98).

CONCLUSION

CAS with DLS seems to reduce the risk of post-procedural stroke for symptomatic patients compared to SLS whilst the choice of stent did not influence ipsilateral TIA, survival or patency rates. These data require confirmation from larger, randomized, prospective studies.

Carotid artery interventions - endarterectomy versus stenting

Current management of patients with carotid artery stenosis is based on well-established guidelines, including surgical procedures - carotid endarterectomy (CEA) and endovascular carotid artery stenting (CAS) - and optimal medical treatment alone. Outcomes in the postprocedural period after CAS and CEA are similar, suggesting strong clinical durability for both treatments. Recent advances, which include the emergence of novel endovascular treatment tools and techniques, combined with more recent randomised trial data shed new light on optimal patient selection and treatment in contemporary practice. Improved, modern technologies including enhanced embolic protection devices and dual-layered micromesh stents yield better outcomes and should result in further improvements in CAS. In centres of excellence, nowadays, the majority of patients with severe carotid artery stenosis can be successfully treated with either CEA or CAS.

Procedural embolic protection strategies for carotid artery stenting: current status and future prospects

INTRODUCTION

Carotid artery angioplasty and stenting (CAS) is an established procedure to treat carotid artery stenosis for either primary or secondary prevention of stroke. Randomized clinical trials have shown an increased risk of periprocedural cerebrovascular events with CAS compared with carotid endarterectomy (CEA). Several strategies have been proposed to mitigate this risk, including alternative vascular access site, proximal/distal embolic protection devices, and dual-layer stents, among others.

AREAS COVERED

This review provides a general overview of current embolic protection strategies for CAS. The phases of the procedure which can affect the early risk of stroke and how to reduce it with novel techniques and devices have been discussed.

EXPERT OPINION

Innovations in device technologies have dramatically improved the safety and efficacy of CAS. To minimize the gap with surgery, a thorough, patient-oriented approach should be pursued. Endovascular technologies and techniques should be selected on an individual basis to address unique lesion characteristics and vascular anatomies. Meticulous pre-procedural planning, both clinical and anatomical, is needed to assess the embolic risk of each procedure. Only by having an in-depth understanding of the wide range of available endovascular devices and techniques, the operator will choose the most appropriate strategy to optimize CAS results.

Comparison of the Outcome and Efficacy of Single-Layer versus Dual-Layer Mesh Stent among Carotid Stenosis Patients Attending a Tertiary Care Setting—A Prospective Observational Study

Introduction The effect of stent design whether single-layer or double-layer on long-term durability of carotid artery stenting (CAS) is unknown. The aim of this article was to compare the clinical outcome and efficacy of single-layer versus dual-layer mesh stent for CAS among carotid stenosis patients.

Methods A prospective observational study was conducted among 41 consecutive patients, who underwent CAS procedures between November 2019 and November 2021. Procedural data and outcomes for patients treated with the single-layer stent (n = 19patients) and double-layer stent (n = 22) were compared. Procedural efficacy and complications were considered as primary outcome variable. SPSS version 22 was used for statistical analysis.

Results Mean age of study population in dual-layer stents group was 63.86 ± 11.08 years and it was 61.47 ± 8.26 years in single-layer stent group. There was no statistically significant difference between two groups with age, stenosis, side of stenosis, prestenting angioplasty, and poststenting angioplasty (p-value >0.05). Out of 22 participants with dual-layer stent, only one (4.5%) participant experienced five episodes of transient ischemic attack in last 1 month. Both clinical and associated complaints were more in dual-layer group compared with single layer. One (5.26%) participant in single-layer group had reclusion/restenosis at 30 days. Majority in single-(57.8%) and double-layer (63.64%) stents group showed modified Rankin Scale score of 0.

Conclusion Restenosis after CAS occurred less frequently in patients treated with double-layer mesh when compared with single-layer stent. However, both stents were equally effective at preventing peri procedural complications.

Comparison of Restenosis Risk in Single-Layer versus Dual-Layer Carotid Stents: A Duplex Ultrasound Evaluation

PURPOSE

The aim of this study was to report intermediate-term results of duplex ultrasound follow-up of carotid artery stenting performed with the dual-layer stent as compared to concurrent patients treated with other commercially available single-layer carotid stents.

MATERIALS AND METHODS

A single centre, retrospective, nonrandomized study including 162 non-consecutive patients with 199 implanted carotid stents treated over a 7-year period was conducted. Patients with at least one ultrasound examination after treatment were included. Procedural and follow-up data for patients treated with the dual-layer stent implantation (83 stents) vs first-generation carotid stents implantations (116 stents) were compared.

RESULTS

The median follow-up time was 24.0 months (IQR 10-32 months) for dual-layer stents and 27.5 months (IQR 10.3-59 months) for single-layer stents. The rate of severe restenosis was significantly higher in the dual-layer stent group than in the single-layer group (13.3% [11/83] vs 3.4% [4/116], p = 0.01). Seven reinterventions were performed in 5 patients with dual-layer stents. The rate of reintervention was significantly higher compared to no reinterventions in single-layer stents (6% [5/83] vs 0% [0/116], p = 0.012). Patients with restenosis had significantly higher presence of dyslipidaemia (100% [12/12] vs 63.3% [95/150], p = 0.009).

CONCLUSIONS

In this real-world cohort of patients undergoing carotid artery stenting, the patients treated with low-profile dual-layer micromesh stent showed higher rates of restenosis and reinterventions compared to first-generation single-layer stents.

“Real-World Study of a Dual-Layer Micromesh Stent in Elective Treatment of Symptomatic and Asymptomatic Carotid Artery Stenosis (ROADSAVER)”

Purpose

Endovascular carotid artery stenosis treatment is associated with a higher peri- and early post-procedural stroke risk relative to surgery. Dual-layer micromesh carotid stents were specifically designed for improved plaque coverage to reduce the cerebral embolization risk and related ischemic events. ROADSAVER study aims to further confirm the safety and efficacy of the Roadsaver™ dual-layer micromesh stent for the treatment of elective patients with carotid artery stenosis.

Materials and Methods

ROADSAVER is a prospective, multi-center, observational study. Between January 2018 and February 2021, a total of 1967 patients featuring asymptomatic or symptomatic, non-occlusive and non-thrombotic carotid stenosis eligible for an elective stenting procedure were enrolled across 13 European countries (52 centers). Follow-up visits are scheduled at 30 days and at 12 months. The primary outcome measure is the major adverse event rate, i.e., cumulative incidence of any death or stroke up to 30 days post-procedure. All deaths, strokes and carotid revascularizations are adjudicated by an independent Clinical Events Committee. Sub-analyses are prespecified and focused on baseline patient characteristics (e.g., age, neurologic status), procedural features (e.g., access route, embolic protection use), advanced imaging, and treatment efficacy up to 12 months.

Conclusion

The present study evaluates the Roadsaver™ dual-layer micromesh carotid stent in the real-world clinical practice aiming to provide valuable insights into the contemporary European treatment trends and outcomes of elective carotid artery stenting. The large study population and predefined sub-analyses should help identify the best practices and patient subsets to benefit most from the treatment.

Trial Registration

Clinicaltrial.gov identifier: NCT03504228.

Carotid Endarterectomy versus Carotid Artery Stenting With Double-Layer Micromesh Carotid Stent: Contemporary Results of a Single-Center Retrospective Study

BACKGROUND

Severe carotid stenosis (CS) is a major risk factor for stroke. Carotid Endarterectomy (CEA) is the gold standard revascularization technique of CS while carotid artery stenting (CAS) is considered an alternative treatment option, especially in high-risk patients or those with relative contraindications to CEA. The aim of this study was to evaluate the results of CEA and CAS with Roadsaver® stent device.

METHODS

We made a retrospective analysis of 119 patients undergoing treatment of CS. All CS were evaluated with imaging exams. The patients were divided into CEA group and CAS group. As primary endpoints of the study overall and cardiovascular cause - related mortality, freedom from stroke, and restenosis were considered. All patients were followed up and revaluated with duplex scan over a minimum of 6 months and a maximum of 36 months (follow-up mean time 22.3 ± 3.4 months).

RESULTS

In the whole cohort 86 of 119 patients underwent CEA and 33 of 119 CAS. Risk factors were superposable in both groups. During follow-up, we observed 4 deaths, 2 cardiovascular events and 12 restenosis. CEA was associated with lower death probability than CAS (P = 0.036). Probability of Restenosis and cardiovascular events did not vary between CAS and CEA groups.

CONCLUSIONS

Albeit CEA remains the gold standard for the treatment of severe CS, CAS with new double layer micromesh stent can be considered a useful and safe alternative in some clinical conditions.