Short-Term Double Layer Mesh Stent Patency for Emergent or Elective Carotid Artery Stenting

The Dual-layer CGuard Stent Is Safe and Effective in Emergent Carotid Artery Stenting and in Tandem Occlusions: a Multi-centric Study

BACKGROUND

Dual-layer stents have fallen into disrepute after several studies reported high rates of in-stent occlusions in acute stroke treatments. The CGuard stent is a new-generation hybrid dual-layer stent that has been designed to provide less thrombogenicity and to prevent peri- and postinterventional emboli. The aim of the study is to evaluate the safety and efficacy of the CGuard stent for the acute treatment of occlusion or high-grade stenosis of the extracranial internal carotid artery (ICA) in patients with acute ischemic stroke (AIS) with and without concomitant intracranial large vessel occlusion (LVO).

METHODS

All patients who underwent emergent carotid artery stenting (CAS) with the CGuard stent were identified and analyzed from the stroke registries from four tertiary German stroke centers. Clinical, procedural, and imaging data were evaluated. Stent patency within 72 h, intracranial hemorrhage, and modified Rankin score (mRS) at discharge were the safety and efficacy end points.

RESULTS

Overall, ninety-six patients were included (mean age 70.2 ± 11.8, 66 males (68.8%), median NIHSS score at admission 11 (7-17), IV lysis: n = 44 (45.8%)). Stent placement was successful in all patients. Eighty-three (86.4%) patients had tandem occlusions. In-stent occlusion occurred in 5 patients (5.2%) and 3 patients developed early in-stent stenosis (3.1%). Median mRS at discharge was 2 (1-4).

CONCLUSION

In this multicenter study, the use of the dual-layer CGuard stent for emergent CAS, particularly in tandem occlusions, was safe and resulted in low rates of in-stent occlusions.

Profile of antiplatelet regimens for emergent carotid stenting in tandem occlusion. Systematic review and meta-analysis

AIM

To investigate the optimum antiplatelet therapy regimen (APTR) for emergent carotid artery stenting following mechanical thrombectomy (MT) in stroke patients with tandem occlusion.

METHODS

A literature search was performed on Pubmed/OVID/Cochran's CENTRAL database for studies from 2015 to 2022. Patient characteristics, antiplatelet regimen type, mTICI, 90 days-mRS, acute in-stent thrombosis (AIST), mortality, intracranial hemorrhage (ICH), and sample size were recorded. Exclusion criteria were non-English literature, sample size < 5 patients, other anticoagulant/antiplatelet therapy, and 100 % stent insertion in one study arm. The studies were assessed using MINORS/GRADE. Meta-analysis and meta-regression with a random effects model were performed. The outcomes were: 90 days-mRS, death, AIST and ICH RESULTS: Five-hundred-twenty-four studies were retrieved. After applying the exclusion criteria, the final population included 19/534 studies (3.6 %) for 880 patients (46.3 per article). I^2 and Q's Cochrane were 86.4 % and 132.5 for mRS, 19.9 % and 17.5 for death, 0 % and 9.4 for acute in-stent thrombosis and 62.1 % and 39.7 for intra-cranial haemorrhages, respectively. Patients in the aspirin subgroup had a significantly lower rate of functional independence (mRS≤2) than those in the DAPT subgroup (47 % [CI95 % 42.0 %-52.0 %] vs. 61.9 % [CI95 % 50.8-72.9]; p=0.0007;OR 0.75[CI95 % 0.56-1.01], p=0.06). DAPT significantly decreased the death rate compared with aspirin (8.6 % [CI95 % 5.3 %-11.9 %] vs. 16.7 % [CI95 11.1 %-22.2 %]; p=0.0012). Anti-GPIIb/IIIa demonstrated a trend of increasing the probability of mortality versus DAPT (OR 1.88[CI95 % 0.93-3.86], p=0.08. No significant differences were observed between AIST and ICH in the treatment groups.

CONCLUSION

DAPT may increases the chance of obtaining an mRS score ≤2 and reduces mortality.

Carotid single- and dual-layer stents reduce the wall adhesion of platelets by influencing flow and cellular transport

An ongoing thrombosis on a ruptured atherosclerotic plaque in the carotid may cause stroke. The primary treatment for patients with tandem lesion is stenting. Dual-layer stents have been introduced as an alternative to single-layer stents for elective and emergent carotid artery stenting. While the dual-layer structure shows promise in reducing plaque prolapse through the stent struts and with it the occurrence of post-procedural embolism, there are early signs that this newer generation of stents is more thrombogenic. We investigate a single- and a dual-layer stent design to assess their influence on a set of thrombosis-related flow factors in a novel setup of combined experiments and simulations. The in vitro results reveal that both stents reduce thrombus formation by approximately 50% when human anticoagulated whole blood was perfused through macrofluidic flow chambers coated with either collagen or human atherosclerotic plaque homogenates. Simulations predict that the primary cause is reduced platelet presence in the vicinity of the wall, due to the influence of stents on flow and cellular transport. Both stents significantly alter the near-wall flow conditions, modifying shear rate, shear gradient, cell-free zones, and platelet availability. Additionally, the dual-layer stent has further increased local shear rates on the inner struts. It also displays increased stagnation zones and reduced recirculation between the outer-layer struts. Finally, the dual-layer stent shows further reduced adhesion over an atherosclerotic plaque coating. The novel approach presented here can be used to improve the design optimization process of cardiovascular stents in the future by allowing an in-depth study of the emerging flow characteristics and agonist transport.

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.

Impact of Carotid Stent Design on Embolic Filter Debris Load During Carotid Artery Stenting

BACKGROUND

The carotid stent design may influence the risk of embolization during carotid artery stenting. The aim of the study was to assess this risk by comparing the quantity of embolized material captured by filters during carotid artery stenting, using different stent designs.

METHODS

We conducted a single-center retrospective study of patients undergoing carotid artery stenting for asymptomatic carotid stenosis >70% (2010-2022) in a tertiary academic hospital (Padua University Hospital, Italy). Carotid stents were classified according to their design as open-cell (OCS), closed-cell (CCS), or micromesh stents (MMS). A distal filter protection was used in all patients, and the amount of captured embolized particles was semiautomatically analyzed using a dedicated software (Image-Pro Plus, Media Cybernetics). Primary end point was embolic filter debris (EFD) load, defined as the ratio of the filter area covered by particulate material to the total filter area. Secondary end points were 30 days major stroke and death.

RESULTS

Four-hundred-eighty-one carotid artery stentings were included; 171 (35%) using an OCS, 68 (14%) a CCS, and 242 (50%) a MMS. Thirty-days mortality was 0.2% (n=1) and major stroke rate was 0.2% (P=0.987). Filters of patients receiving MMS were more likely to be free from embolized material (OCS, 30%; CCS, 13%; MMS, 41%; P<0.001) and had a lower EFD load (OCS, 9.1±14.5%; CCS, 7.9±14.0%; MMS, 5.0±9.1%; P<0.001) compared with other stent designs. After stratification by plaque characteristics, MMS had a lower EFD load in cases of hypoechogenic plaque (OCS, 13.4±9.9%; CCS, 10.9±8.7%; MMS, 6.5±13.1%; P<0.001), plaque length>15 mm (OC, 10.2±15.3; CC, 8.6±12.4; MM, 8.2±13.6; P<0.001), and preoperative ipsilateral asymptomatic ischemic cerebral lesion (OCS, 12.9±16.8%; CCS, 8.7±19.5%; MMS, 5.4±9.7%; P<0.001). After multivariate linear regression, use of MMS was associated with lower EFD load (P=0.038).

CONCLUSIONS

The use of MMS seems to be associated with a lower embolization rate and EFD load, especially in hypoechogenic and long plaques and in patients with a preoperative evidence of asymptomatic ischemic cerebral lesion.

Safety and Efficacy of Carotid Artery Stenting with the CGuard Double-layer Stent in Acute Ischemic Stroke

BACKGROUND

Double-layer stents show promising results in preventing periinterventional and postinterventional embolic events in elective settings of carotid artery stenting (CAS). We report a single-center experience with the CGuard stent in the treatment of acute ischemic stroke (AIS) due to symptomatic internal carotid artery (ICA) stenosis or occlusion with or without intracranial occlusion.

METHODS

We retrospectively analyzed all patients who received a CGuard stent in the setting of AIS at our institution. Neuroimaging and clinical data were analyzed with the following primary endpoints: technical feasibility, acute and delayed stent occlusion or thrombosis, distal embolism, symptomatic intracranial hemorrhage (sICH) and functional outcome at 3 months.

RESULTS

In 33 patients, stenting with the CGuard was performed. Stent deployment was successful in all patients (28 with tandem occlusions, 5 with isolated ICA occlusion). Transient acute in-stent thrombus formation occurred in three patients (9%) without early stent occlusion. Delayed, asymptomatic stent occlusion was seen in 1 patient (3%) after 49 days. Asymptomatic periinterventional distal emboli occurred in 2 patients (6%), 1 patient experienced a transient ischemic attack 79 days after the procedure and 1 patient (3%) developed sICH. Favorable clinical outcome (mRS 0-2) at 3 months was achieved in 12 patients (36%) and the mortality rate was 24%.

CONCLUSION

The CGuard use in emergencies was technically feasible, the safety has to be confirmed by further multicentric studies.

Dual-layer carotid stenting for symptomatic carotid web: Results from the Caroweb study

BACKGROUND & PURPOSE

Carotid Web (CaW) is a growingly recognized cause of ischemic stroke, associated with a high recurrence risk. Several therapeutic strategies have been proposed as a tertiary prevention including carotid stenting, endarterectomy and antithrombotic medications. Among these, carotid stenting with dual-layer stent may be promising to adequately cover the focal arterial dysplasia. Our aim was to investigate the safety and efficacy of the Casper stent in the treatment of symptomatic CaW.

METHODS

We conducted a retrospective analysis of consecutive patients presenting with a symptomatic CaW and included in the ongoing prospective observational multicenter CAROWEB registry. The study period was January 2015 to December 2021. Inclusion criteria were CaW treated with dual-layer Casper stent. Patients treated with other types of carotid stent, endarterectomy or antithrombotic medication were excluded. Clinical and radiological initial data and outcomes were recorded.

RESULTS

twenty-seven patients (with 28 caw) were included. median age was 52 (iqr: 46-68). median delay between index cerebrovascular event and cervical stenting was 9 days (IQR: 6-101). In all cases, the cervical carotid stenting was successfully performed. No major perioperative complication was recorded. No recurrent stroke or transient ischemic attack was observed during a median follow-up time of 272 days (IQR: 114-635). Long-term imaging follow-up was available in 25/28 (89.3%) stented CaW with a median imaging follow-up of 183 days (IQR: 107-676; range: 90-1542). No in-stent occlusion or stenosis was detected.

CONCLUSION

In this study, carotid stenting with dual-layer Casper stent in the treatment of symptomatic CaW was effective regarding stroke recurrence prevention and safe, without procedural nor delayed detected adverse event. However, the optimal therapeutic approach of symptomatic CaW still needs to be explored through randomized trials.

1-Year Results From a Prospective Experience on CAS Using the CGuard Stent System: The IRONGUARD 2 Study

OBJECTIVES

The aim of this study was to evaluate the 1-year safety and efficacy of a dual-layered stent (DLS) for carotid artery stenting (CAS) in a multicenter registry.

BACKGROUND

DLS have been proved to be safe and efficient during short-term follow-up. Recent data have raised the concern that the benefit of CAS performed with using a DLS may be hampered by a higher restenosis rate at 1 year.

METHODS

From January 2017 to June 2019, a physician-initiated, prospective, multispecialty registry enrolled 733 consecutive patients undergoing CAS using the CGuard embolic prevention system at 20 centers. The primary endpoint was the occurrence of death and stroke at 1 year. Secondary endpoints were 1-year rates of transient ischemic attack, acute myocardial infarction, internal carotid artery (ICA) restenosis, in-stent thrombosis, and external carotid artery occlusion.

RESULTS

At 1 year, follow-up was available in 726 patients (99.04%). Beyond 30 days postprocedure, 1 minor stroke (0.13%), four transient ischemic attacks (0.55%), 2 fatal acute myocardial infarctions (0.27%), and 6 noncardiac deaths (1.10%) occurred. On duplex ultrasound examination, ICA restenosis was found in 6 patients (0.82%): 2 total occlusions and 4 in-stent restenoses. No predictors of target ICA restenosis and/or occlusion could be detected, and dual-antiplatelet therapy duration (90 days vs 30 days) was not found to be related to major adverse cardiovascular event or restenosis occurrence.

CONCLUSIONS

This real-world registry suggests that DLS use in clinical practice is safe and associated with minimal occurrence of adverse neurologic events up to 12-month follow-up.

Procedural Stroke after Carotid Revascularization - Critical Analysis of the Literature and Standards of Reporting

OBJECTIVE

Mechanisms of procedural stroke after carotid endarterectomy (CEA) or stenting (CAS) are surprisingly underresearched. However, understanding the underlying mechanism could: (1) assist in balancing the choice for revascularization versus conservative therapy; (2) assist in choosing either open or endo techniques; and (3) assist in taking appropriate periprocedural measures to further reduce procedural stroke rate. The purpose of this study was to overview mechanisms of procedural stroke after carotid revascularization and establish reporting standards to facilitate more granular investigation and individual patient data meta-analysis in the future.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) statement.

RESULTS

The limited evidence in literature was heterogeneous and of low quality and hence no formal data meta-analysis could be performed. Procedural stroke was classified as haemorrhagic or ischemic; the latter was subclassified as haemodynamic, embolic (carotid- or cardio-embolic) or carotid occlusion-derived, using a combination of clinical inference and imaging data. Most events occurred in the first 24h after the procedure and were related to hypoperfusion (pooled incidence 10.2% (95% c.i. 3.0-17.5) versus 13.9% (95% c.i. 0.0-60.9) post-CEA vs CAS events, respectively) or atheroembolism (28.9% (95% c.i. 10.9-47.0) versus 34.3 (95% c.i. 0.0-91.5)) After the first 24 hours, haemorrhagic stroke (11.6 (95% c.i. 5.7-17.4) versus 9.0 (95% c.i. 1.3-16.7)) or thrombotic occlusion (18.4 (95% c.i. 0.9-35.8) versus 14.8 (95% c.i. 0.0-30.5)) became more likely.

CONCLUSIONS

Although procedural stroke incidence and aetiology may have changed over the last decades due to technical improvements and improvement in perioperative monitoring and quality control, the lack of literature data limits further statements. To simplify and enhance future reporting, procedural stroke analysis and classification should be documented pre-emptively in research settings. We propose a standardized form enclosing reporting standards for procedural stroke with a systematic approach to inference of the most likely aetiology, for prospective use in registries and RCTs on carotid revascularization.

Endovascular treatment of extracranial carotid artery stenosis using a dual-layer micromesh stents: a systematic review

Introduction: We aimed to review the safety and effectiveness of dual-layer micromesh stents for the endovascular treatment of carotid artery stenosis.Methods: Electronic bibliographic databases were searched using the words 'micromesh carotid stent'. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards.Results: The search of the Literature retrieved 84 results. After assessment of full texts, 13 papers were included in the study. The analyzed studies included 797 patients, 32.1% of them were symptomatic. The reported technical success rate was 100% in all cases. During early follow-up, complications occurred overall in 16/797 patients (2%: 12 strokes, 3 deaths, and one transient ischemic attack). The study with the longest follow-up reported a survival rate of 82% at 4 years and a stroke-free survival rate of 84% at 4 years.Conclusion: With the limit of low data quality, the use of dual-layer stents was reported to be as safe and effective at 30 days for the endovascular treatment of extracranial carotid artery stenosis. The reported technical success was 100% in all cases. Further data coming from randomized controlled trials and larger cohort studies with longer follow-up are nevertheless needed for a better evaluation.

Effectiveness and safety of dual-layer stents in carotid artery disease: a systematic review

INTRODUCTION

Carotid artery stenting (CAS) has emerged as a minimally invasive alternative to carotid endarterectomy (CEA) in atherosclerotic carotid artery disease, even though the risk for procedural stroke after CAS remains significantly higher. Recently, in order to reduce embolic cerebral events after CAS, a new generation of dual-layer stents (DLS) has been developed. This review aimed to perform a detailed analysis of the available evidence on safety and efficacy of DLS in both symptomatic and asymptomatic atherosclerotic carotid artery stenosis.

EVIDENCE ACQUISITION

A systematic review was conducted according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The primary endpoint was the 30-day rate of myocardial infarction (MI), stroke and death. Secondary outcomes included rate and timing of stent occlusion/restenosis.

EVIDENCE SYNTHESIS

A total of 20 articles with 1193 patients were included. Thirty-day MI ranged from 0-5%, 30-day stroke ranged from 0-10.5% and 30-day mortality ranged from 0-10%. Stent occlusion rate ranged from 0-52.4%, the majority of which occurred intraprocedurally (N.=50; 61.7%), in emergency treated patients. The incidence of new ipsilateral cerebral ischemic lesions after CAS with DLS was reported in five studies, ranging from 5.5-37%.

CONCLUSIONS

Despite the theoretic advantage of reducing the risk for procedural embolic events when compared to conventional stents, high quality evidence is scarce. Also, safety issues regarding DLS in the emergency setting have been raised, particularly for thrombotic complications. Additional data from well-designed Randomized Controlled Trials are needed to assert the true value of DLS.

Critical Appraisal on the Quality of Reporting on Safety and Efficacy of Transcarotid Artery Stenting With Flow Reversal

Transcarotid revascularization is an alternative to transfemoral carotid artery stenting, designed to avoid aortic arch manipulation and concomitant periprocedural stroke. This article aims to perform a detailed analysis on the quality of the currently available evidence on safety and efficacy of transcarotid artery revascularization. Although current evidence is promising, independent randomized controlled studies comparing transcarotid artery revascularization with carotid endarterectomy in recently symptomatic patients are lacking and will be necessary to establish the true value of transcarotid artery revascularization in carotid artery revascularization.

Carotid Artery Stenting Using a Double-layer Micromesh Stent

Carotid artery stenting (CAS) has recently emerged as a potential alternative to carotid endarterectomy (CEA) in Japan. However, one of its disadvantages is the higher incidence of ischemic complications than CEA, such as distal embolism during or after the procedure. Plaque protrusion (PP) through the stent strut after deployment of the stent has been suggested as one of the major causes of distal embolism, especially in patients with unstable plaques. The need for increased plaque coverage to reduce the risk of PP through the stent struts has led to the development of a double-layer micromesh stent (micromesh stent) system. This stent system has already been used clinically in European countries with good short- to medium-term follow-up results. Also clinical trials evaluating micromesh stents have been completed in Japan. Hence, usefulness of the micromesh stent for CAS is expected. According to the results of several clinical studies, CAS with the double-layer micromesh stent has the potential to minimize distal embolism during or after the procedure even in patients with unstable plaques. However, it may not be suitable for emergency CAS at this point. Also, since results of only short- to medium-term follow-up have been reported, longer-term follow-up will be required in the near future.

Emergency carotid artery revascularization using Casper-RX stent: A single-center experience

BACKGROUND

Casper-RX (MicroVention, Aliso Viejo, California, USA) is a dual-layer closed cell stent recently introduced as a carotid artery revascularization device. Although its effectiveness and safety has been proved in elective cases, there are contradictive results regarding its patency in emergency settings. The purpose of the study is to present our single-center experience with the Casper-RX stent in the emergency interventions.

PATIENTS AND METHODS

Consecutive patients who underwent emergency carotid artery stenting using Casper-RX system with or without additional intracranial thrombectomy between August 2016 and June 2019 at our institution were included. Primary end point was the short-term patency of the carotid stents evaluated before hospital discharge by use of Doppler ultrasonography.

RESULTS

Twenty-nine procedures performed on 28 patients were included in the study. All stents were patent on final angiograms. Acute stent occlusion was observed only in one case (3.4%) with a spontaneous cervical internal carotid artery dissection the day after the procedure. In 26 (89.6%) cases, an additional intracranial thrombectomy was performed with a successful recanalization rate of 96.1%. Seven adverse events occurred peri-/post-procedural: two cases (6.9%) with iatrogenic dissection of distal cervical internal carotid artery during intracranial thrombectomy, two parenchymal hematoma type 2 (6.8%), and three patients (10.3%) developed massive infarction.

CONCLUSION

This study supports the safety and efficacy of the Casper-RX stent in emergency endovascular carotid artery revascularization procedures.