Abstract
Background:
Dual-layer micromesh (DLMM) carotid stents were developed to enhance plaque scaffolding and reduce peri-procedural embolization during carotid artery stenting (CAS). Although Roadsaver is widely used in contemporary European practice, comparative evidence against first-generation stents (FGSs) and other DLMM devices remains limited. This study systematically reviews the European experience with Roadsaver and performs an exploratory meta-analysis of 30-day clinical outcomes and in-stent restenosis (ISR).
Methods:
A systematic search of PubMed, Embase, and Medline identified European studies published between January 1, 2014 and December 31, 2024 reporting transfemoral CAS using the Roadsaver stent. Adult patients with extracranial, de novo carotid stenosis—symptomatic or asymptomatic—were included. Comparative analyses were limited to studies reporting paired outcomes for Roadsaver versus FGSs or C-Guard. Primary endpoints were 30-day stroke and death; the secondary endpoint was ≥50% ISR at approximately 12 months, as defined by each study. Pooled effects were calculated using Peto odds ratios with random-effects DerSimonian-Laird models.
Results:
Twenty-two studies comprising 3539 Roadsaver procedures were included in the qualitative review; 5 studies met criteria for quantitative pooling. Across all studies, 30-day stroke and death occurred in 1.6% and 0.5% of patients, respectively. Meta-analysis showed no statistically significant differences in 30-day stroke or death between Roadsaver and FGSs, with low heterogeneity. In-stent restenosis comparisons similarly demonstrated no significant differences between Roadsaver and FGSs or between Roadsaver and C-Guard; however, ISR analyses were limited by marked heterogeneity in definitions, imaging modalities, and follow-up timing.
Conclusions:
Roadsaver DLMM stenting in European practice is associated with low 30-day stroke and death rates. Exploratory pooled analyses did not identify significant differences between Roadsaver and FGSs or between DLMM devices; however, the small number of comparative studies, variability in ISR assessment, and predominantly observational evidence base substantially limit the certainty of these findings. Larger, rigorously designed comparative studies, and randomized trials are needed to determine whether clinically meaningful differences exist between carotid stent platforms.
Clinical impact
In this paper, transfemoral CAS with the Roadsaver dual-layer micromesh stent was associated with low 30-day stroke and death rates in European practice. Comparative analyses did not demonstrate significant differences versus first-generation stents or between DLMM devices; however, the observed safety profile, combined with mechanistic data on enhanced plaque scaffolding and embolic protection, supports the use of Roadsaver in routine CAS, including complex anatomies. These findings reinforce DLMM technology as a contemporary standard option rather than an experimental alternative, while underscoring the need for standardized ISR assessment and adequately powered randomized trials to guide device selection in carotid revascularization.
Keywords
Introduction
Endovascular treatment for carotid artery stenosis represents a minimally invasive approach that is living a new interest in vascular surgery field. In the latest 10 years, a new technology based on dual-layer micromesh (DLMM) folding for carotid artery stent (CAS) has strongly influenced the choice of the best treatment. The so-called first generation of carotid stents, 1 represented by open-cell (OC) and closed-cell (CC) stents, dominated for more than a decade the technology choose for CAS. At the same time, the growing CAS expertise, better patient selection, lesion-tailored strategies, and evermore advanced techniques and devices continuously improve CAS outcomes. Accordingly, the 2023 European guidelines recommend CAS in patients at high risk for surgery. 2 While CAS provides a minimally invasive alternative to carotid endarterectomy, the risk of peri-procedural and early post-procedural distal embolization events with potential neurological sequalae warrants further attention. 3 Dual-layer micromesh stents were specifically designed for improved lesion coverage and prevention of plaque prolapse (PP) through the stent struts, to minimize the ischemic events during and after CAS. Different materials (nitinol or cobalt-chromium) and shapes (tapered vs straight) of CASs provide a range of geometries and mechanical properties. 4 Characteristics such as high flexibility are needed to preserve vessel contours and radial force, wall apposition, and plaque coverage are required to prevent late embolic release. Despite the variety of available CASs, there remains the desire to develop and improve the materials and designs to achieve sustained, permanent embolic protection. 5 Dual-layer micromesh stents are thought to minimize the embolic potential from the plaque, 6 and are represented by 2 products, Roadsaver /Casper (Terumo Corp, Tokyo, Japan) and C-Guard (InspireMD Inc, Boston, Maryland), both of which showed encouraging preliminary results. In this study, we evaluated patients with extracranial carotid atherosclerotic stenosis (both symptomatic and asymptomatic) undergoing transfemoral CAS in European studies. The intervention of interest was the DLMM Roadsaver stent, compared primarily with first-generation stents (FGS, OC or CC designs), and secondarily with the DLMM C-Guard stent. The outcomes assessed were the 30-day incidence of stroke and death, and the 12-month in-stent restenosis (ISR) rate. We present a systematic review of literature about the use of DLMM Roadsaver stent for the treatment of carotid artery stenosis and a meta-analysis to evaluate the 30-day stroke rate, 30-day death rate, and restenosis rate in comparison with first-generation carotid stents. In addition, we perform meta-analysis to understand if there are some differences about ISR results between 2 DLMM stents, as recently suggested in the literature. 1
Roadsaver Stent Technology Details
The DLMM Roadsaver stent is a device composed of an inner nitinol braided mesh integrated with an external closed-cell scaffold, resulting in a cell size of approximately 375 to 500 µm—significantly smaller than that of first-generation carotid stents. This configuration enhances plaque coverage and limits prolapse of friable material through the struts. A key characteristic of the Roadsaver platform is its low-profile design, allowing delivery through 5 F introducer sheaths. This feature contributes to excellent crossability and navigability in challenging vascular anatomies, including type II/III aortic arches, elongated or tortuous common carotid arteries, and angulated carotid bifurcations. The device has demonstrated reliable performance even in anatomies where prior attempts with larger-profile systems have failed. The retrievable and repositionable design (recommended up to 50% deployment) further enhances accuracy during stent placement. The low crossing profile and high flexibility also facilitate radial and ulnar access approaches, which have gained increasing utilization in contemporary European practice, particularly when transfemoral access is unfavorable. These attributes have been supported in recent clinical evaluations of low-profile DLMM stents, including the comparative experience reported by Kahlberg et al, 7 who described favorable deliverability and procedural success in patients with complex anatomy undergoing CAS using this platform. Overall, the Roadsaver stent combines enhanced plaque scaffolding with a low-profile, highly navigable delivery system, enabling safe and versatile use across a broad spectrum of carotid anatomies and access routes. 8
Materials and Methods
The systematic review and meta-analysis were performed according to the Cochrane Collaboration recommendations. 9 A rigorous protocol was established before the analyses, concerning all the objectives, inclusion and exclusion criteria, primary and secondary outcomes, and synthesis methods. We reported the results according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) 10 and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 11 recommendations.
Literature Search Strategy
Electronic databases, including PubMed, Embase, and Medline were searched in the period interval between January 1, 2014 and December 31, 2024, for potentially eligible European studies published in English language. The reference lists of the gathered reports were manually searched for relevant articles. The following medical subject headings were used “roadsaver AND carotid AND stent AND ‘article’/it AND [english]/lim AND ([embase]/lim OR [medline]/lim OR [pubmed-not-medline]/lim) AND [01-01-2014]/sd NOT [01-01-2025]/sd.” We did not use the “Casper” term (the other name of Roadsaver stent for Asian countries). The search was restricted to the English language and to European populations to ensure procedural and demographic homogeneity. The reference lists of all included reports were also screened manually to identify additional relevant articles. The review protocol was developed a priori and registered on PROSPERO, followed a predefined methodology based on the PRISMA 2020 and MOOSE recommendations.10,11 A PRISMA 2020 flow diagram (Figure 1) summarizes the identification, screening, eligibility, and inclusion phases across databases and manual searches. All duplicate records were removed before screening.
PRISMA 2020 flow diagram of study selection process. 44
The study project was registered in the international prospective register of systematic reviews (PROSPERO 2026 CRD420260634875, https://www.crd.york.ac.uk/PROSPERO/view/CRD420260634875).
Clinical Outcomes of Interest
The primary clinical outcomes were 30-day stroke and 30-day death. For the purposes of this study, 30-day stroke was defined as:
Any new focal neurological deficit of presumed vascular origin, lasting more than 24 hours, occurring within 30 days of the CAS procedure, including both minor and major strokes. When studies distinguished between ipsilateral and contralateral events, all clinically reported strokes were included in the pooled analysis, as most studies did not separately quantify ipsilateral events. When definitions varied between studies, the broadest category (“any stroke within 30 days”) was used to ensure consistent outcome harmonization. This harmonized definition aligns with contemporary carotid stenting literature and minimizes outcome classification bias across heterogeneous observational studies.
The secondary outcome was 12-month ISR as defined by each individual study (commonly duplex peak systolic velocity [PSV] thresholds or imaging-based luminal narrowing). In-stent restenosis definitions varied across the included studies, as no uniform diagnostic standard was consistently applied. In most series, ISR was assessed using duplex ultrasound, with restenosis defined as ≥50% luminal narrowing, usually based on PSV thresholds. The most frequently reported criteria were: PSV ≥200 cm/s (commonly interpreted as ≥50% ISR), PSV ≥230 cm/s (used in several vascular laboratories), and laboratory-specific PSV cut-offs not directly comparable across centers.
In a minority of studies, ISR assessment relied on computed tomography angiography (CTA), magnetic resonance angiography (MRA), or digital subtraction angiography, either alone or as confirmatory imaging. Surveillance intervals also differed between studies, typically ranging from 6 to 24 months. Because of this variability, ISR was harmonized for the purposes of synthesis as the reported binary occurrence of ≥50% restenosis, as defined by each individual study. This heterogeneity in ISR definitions is acknowledged as a major methodological limitation.
Study Eligibility and Quality Assessment
Studies eligible for screening needed to satisfy the criteria of at least 20 patients, de novo atherosclerosis, extracranial carotid procedure, and European population. The following requirements were applied: (1) publication in English, (2) original study publication, (3) human subjects, and (4) stenosis ≤99%. Quality assessment was performed to identify bias in at least one of 5 bias categories (patient selection/recruitment, performance in relation to study device(s), performance other than in relation to study device(s), outcome detection, and attrition and reporting). Both prospective and retrospective studies were considered. A total of 22 records were initially identified (Table 1). Besides the initial screening criteria, for the comparative analyses, the control groups consisted of FGS (OC or CC designs), which represented the standard devices used during the period covered by the included studies. In the secondary comparison, the control group was the DLMM C-Guard stent. Only 5 studies that reported paired, stent-specific outcome data within the same patient cohort were eligible for inclusion in the quantitative synthesis (Table 2). This approach ensured that all comparative estimates reflected direct within-study comparisons, thereby avoiding indirect contrasts across unrelated populations. Case series without a comparator arm and studies with fewer than 20 patients treated with DLMM Roadsaver were excluded from pooled meta-analysis and were incorporated only in the qualitative synthesis.
Results From Review of Literature.
NR = not reported.
Studies Included in Meta-Analysis.
Selection Criteria
Two investigators (G.M. and A.M.) independently performed a literature search. The 2 investigators independently reviewed the titles and abstracts of all citations to identify potentially relevant studies and to exclude duplicates. The investigators reviewed the full text of the corresponding publications to assess whether the studies met the inclusion criteria. The references from the articles obtained were also analyzed. The literature search focused solely on articles published in peer-reviewed journals, to enhance the methodological rigor of studies examined. Studies including treatment for complete carotid occlusion were not included. Studies were excluded from the quantitative pooled analysis if (1) they included only tandem lesions; (2) they overlapped with other papers by the same institution (in such cases, the paper chosen for the meta-analysis was the most recent one or the one with more useful details); or (3) dual antiplatelet therapy was not administrated after carotid stenting (no specific analysis about the type of antiplatelet was performed). If the data allowed to exclude the cases with tandem lesions or acute occlusion, the article was considered for the meta-analysis; otherwise, the study was omitted from meta-analysis. The final inclusion of the studies was based on agreement between the reviewers. Any disagreement was resolved by discussion and consultation with the other coauthors. The methodological quality of included studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklists for Cohort Studies, which are specific to observational designs and appropriate for both retrospective and prospective series. The tool includes 11 domains evaluating patient selection, classification of exposures, completeness of follow-up, outcome assessment, and control of confounders. Two reviewers independently performed the risk-of-bias assessment, with disagreements resolved through consensus. Each domain was rated as low risk, high risk, or unclear risk. A structured summary of the risk-of-bias assessment for each included study is presented in Supplemental Table 1.
Data Extraction
Data were extracted by 2 investigators working together using a predefined data extraction form. In case of disagreement, a third investigator reviewed the publication pertaining to a given study and a consensus was reached.
Data Synthesis
The baseline demographics and outcomes were extracted. In the case of more than 1 publication referring to 30-day or 12-month outcomes from a particular study, the data were integrated.
Statistical Analysis
Outcomes of interest are presented as frequency and percentage (%) as well as risk ratios (95% confidence interval [CI]) for between-group comparisons. The pooled risk was estimated from individual studies using random-effects models calculating the log Peto’s odds ratio (OR) with relative 95% CI. The Peto OR method was selected because several of the included studies reported very low event rates (eg, 30-day stroke and death), with some studies including zero events in one of the treatment arms. Under these conditions, the Peto method has been shown to provide less biased and more stable estimates compared with conventional inverse-variance methods, particularly when event rates are rare and treatment effects are small. Regarding the choice of model, we acknowledge that the Peto method is traditionally implemented within a fixed-effect framework. However, given the clinical and methodological heterogeneity across the included observational studies, we opted to apply a random-effects model (DerSimonian-Laird) to provide more conservative estimates and to better account for between-study variability. We used the heterogeneity χ2 (Cochran Q) statistic to formally analyze heterogeneity across included studies. When Cochran Q P-values was < .10, we pooled risk estimates using random-effects models. The heterogeneity was also represented by I2 index. The potential for publication bias was assessed using a funnel plot in conjunction with weighted Egger. The analysis was carried out with Stata v20.0 (Stata Corp, College Station, Texas).
Results
We found 22 European studies published on principal online libraries (PubMed, Embase, and Medline) in the period interval between January 1, 2014 and December 31, 2024 about use of Roadsaver stents (Table 1). Studies published are: 1 randomized controlled trial (RCT), 18 observational study, and 3 case series. We observed results from 3539 patients treated with DLMM Roadsaver stent in more than 20 countries; 39% of these patients had a symptomatic carotid stenosis.
We registered from the literature examined a total of fifty-six 30-day stroke events (30-day stroke rate: 1.58%) and nineteen 30-day death event (0.5%). Study of Pasqui et al 29 was not included in comprehensive 30-day stroke rate and comprehensive 30-day death rate due to a lack of data about these outcomes. Comprehensive ISR rate is not calculated because not all studies report this outcome.
We performed a meta-analysis for outcomes of study with DLMM Roadsaver and FGS based on data from observational studies (Table 2). The single RCT identified 23 was not included in the pooled quantitative analysis because its design was not comparable to the observational studies. The trial used a 4-arm factorial design combining stent type (DLMM Roadsaver vs FGS Wallstent) and embolic protection method (distal vs proximal), and its primary endpoint was the number of cerebral microembolic signals (MESs)—a surrogate marker not reported in the comparative observational cohorts. In addition, 30-day clinical outcomes were not presented in a way that allowed extraction of Roadsaver-specific results for pooling. Including this study in the meta-analysis would have introduced substantial conceptual and methodological heterogeneity; therefore, it was integrated only qualitatively.
DLMM Rodsaver thirty-day stroke rate showed no statistical significant difference compared to FGS, with no heterogeneity observed, as reported in Figure 2.
Random-effects model used to estimate the pooled risk for 30-day stroke rate.
Thirty-day death rate do not statistically differ between DLMM Roadsaver stent and FGS and no heterogeneity was found, as reported in Figure 3.
Random-effects model used to estimate the pooled risk for 30-day death rate.
In-stent restenosis reporting was highly variable across the included studies, reflecting non-standardized imaging practice and follow-up protocols in real-world European CAS experience. In-stent restenosis rates were reported inconsistently across the included studies, and only a small subset provided sufficiently comparable data for pooled analysis. Three observational studies contributed to the comparison between Roadsaver and FGSs. Across these studies, ISR definitions varied substantially: some used duplex ultrasound with PSV thresholds of ≥200 or ≥230 cm/s, while others used laboratory-specific duplex criteria or cross-sectional imaging (CTA or MRA). Follow-up duration ranged from 6 to 24 months, and imaging schedules were not uniform. The pooled analysis demonstrated no statistically significant difference in ISR between DLMM Roadsaver and FGS (Figure 4); however, heterogeneity was extremely high (Figure 3), indicating substantial variability among study results. Given the small number of available comparative studies and the divergence in ISR definitions, imaging modalities, and follow-up protocols, this heterogeneity likely reflects methodological differences rather than true biological variation Due to the limited number of eligible data sets, formal sensitivity analyses—including exclusion of potential outliers, stratification by imaging modality, or meta-regression based on follow-up duration—were not feasible. As a result, the ISR findings should be interpreted as exploratory and hypothesis-generating, rather than confirmatory.
Random-effects model used to estimate the pooled risk for in-stent restenosis rate between Roadsaver and FGS.
A secondary ISR comparison between DLMM Roadsaver and DLMM C-Guard included only 2 studies. This analysis showed no statistically significant difference, with low heterogeneity (Figure 5). A detailed summary of ISR definitions, percentage thresholds, PSV criteria, and imaging modalities used across the included studies is provided in Supplemental Table 1. These data highlight the substantial methodological variability in ISR assessment. Nonetheless, the limited sample size restricts the strength of inference.
Random-effects model used to estimate the pooled risk for in-stent restenosis rate between Roadsaver and C-Guard.
Discussion
Results from this meta-analysis are represented by:
No statistical differences in of 30-day stroke in patients undergoing CAS between DLMM Roadsaver and FGS.
No statistical differences in of 30-day death in patients undergoing CAS between DLMM Roadsaver and FGS.
No statistical differences in restenosis rate in patients undergoing CAS between DLMM Roadsaver and FGS.
No statistical differences in ISR rate in patient undergoing CAS between DLMM Roadsaver and DLMM C-Guard stent.
These findings should not be interpreted as evidence of equivalence. Non-significant results in this setting reflect the absence of a detectable difference, not proof that the stents perform identically. The available comparative evidence is limited, predominantly observational, and based on small pooled samples, which restricts statistical power and increases the likelihood of type II error. As a result, the analyses are better viewed as exploratory assessments that identify trends but cannot confirm comparative effectiveness. In our systematic review, 1 RCT was identified, but it could not be incorporated into the quantitative synthesis because its design differed fundamentally from that of the comparative observational studies. The trial employed a 4-arm randomization based on both stent type and embolic protection strategy, and its primary endpoint was cerebral MESs measured by transcranial Doppler—a physiological surrogate not available in the other studies. Moreover, the 30-day clinical outcomes were not reported in a manner that allowed isolated extraction of DLMM Roadsaver-specific data. Given these incompatibilities, including the RCT in the pooled estimates would have introduced major methodological heterogeneity. Instead, we have integrated its findings qualitatively: the trial demonstrated a significantly lower microembolic load with the Roadsaver stent compared with the single-layer Wallstent, supporting the mechanistic premise of enhanced plaque scaffolding with DLMM technology. This mechanistic benefit, however, has yet to translate into clear differences in clinical outcomes within the limited comparative evidence base.
The stent in carotid artery intervention plays a unique role in that after the embolic protection system has been removed, the stent is the main line of defense (along with antiplatelet therapy) against embolic and thromboembolic complications that may arise from the newly remodeled plaque with the varying degree of plaque coverage dependent on the stent design. 29 In this meta-analysis, we analyzed studies with a similar design (observational studies: retrospective and perspective) and exclude the only RCT study: the randomization and control group, even though hopeful, are absent in other studies. We found a high heterogeneity grade only in ISR analysis between FGS and DLMM Roadsaver group, while it was low for stroke rate, death rate, and for secondary outcome ISR rate between DLMM Roadsaver and DLMM C-Guard group. Several factors may contribute to high heterogeneity within the pool of CAS data available today. These include differences in study populations (proportion of symptomatic and asymptomatic patients) and different specialties performing the procedures (resulting in differences in patient selection for CAS). A very high level of heterogeneity was observed in the ISR comparison between Roadsaver and FGSs. Several factors likely contributed to this variability. First, ISR definitions were not standardized across studies: some reports defined restenosis using duplex ultrasound alone, while others used CTA or DSA, and PSV thresholds varied considerably (commonly 200 cm/s, 230 cm/s, or laboratory-specific criteria). Second, follow-up imaging schedules differed widely, ranging from 6 to 24 months, and in some series ISR detection relied on problem-oriented imaging rather than systematic surveillance. Third, patient-level factors—such as baseline plaque morphology, degree of stenosis, symptomatic status, and antiplatelet therapy—were inconsistently reported and may have influenced restenosis rates. Finally, technical aspects of the procedures, including post-dilatation practices, stent sizing, and operator experience, also varied and likely contributed to interstudy heterogeneity. Beyond heterogeneity, the overall certainty of evidence is limited by the observational design of nearly all included studies. Using the core GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) domains, the certainty of evidence for all pooled outcomes (30-day stroke, 30-day death, and ISR) is considered low. The main contributors to this rating include: (1) risk of bias, due to unmeasured confounding and the absence of adjusted analyses; (2) inconsistency, particularly in ISR reporting; (3) indirectness, arising from variability in patient selection, plaque characteristics, operator experience, and embolic protection strategies; and (4) imprecision, reflecting the small number of comparative studies. About ISR definition, it varied markedly among studies in terms of imaging modality, percentage stenosis threshold, and PSV criteria. This lack of standardization likely contributed substantially to the very high heterogeneity observed in our ISR meta-analysis. Variability in follow-up duration further contributed to the heterogeneity of ISR reporting. Although ISR was conceptually defined as a 12-month outcome, actual surveillance timeframes differed considerably across studies, with some performing imaging at or near 12 months and others reporting restenosis during longer or irregular follow-up intervals. This inconsistency likely influenced both the absolute ISR rates and the between-study variance, limiting the comparability of results and reinforcing the exploratory nature of the pooled ISR findings.
Most recent and upcoming studies show event rates consistent with the meta-analytic model. In 2023, Desantis et al 30 published results of CATACLISMA (Carotid Artery sTenting And CeLl-area Impact on Stroke and Major Adverse events study), a multicenter, retrospective, financially unsupported physician-initiated observational cohort study conducted by 6 Italian tertiary referral hospitals conducted on asymptomatic carotid artery stenosis ranging from 70% to 99% undergoing transfemoral CAS. A total of 1096 CAS were considered (787 men, 71.8%, median age = 74 years). Three groups were defined based on the cell area: OC design (547), CC design (344), and DLMM design (205). 29 The employed DLMM stents were 159 Roadsaver and 42 C-Guard. 30 In Desantis et al’s 30 analysis, no statistical differences were observed in terms of 30-day stroke rates among groups (1.5%, OC: 1.1%, CC: 2.3%, DLMM: 1%, P = .27), although more patients in the CC group suffered from a stroke event (2.3%, divided equally between major and minor stroke) compared with others, whereas only 2 (minor) stroke were accounted in the DL group. In addition, no gender variable was also evaluated showing no differences between the 3 groups at multivariate analysis. 30 The good outcome in the asymptomatic patients of CAS in the real-world studies can be due to a lower vulnerability of the carotid plaque in these patients; furthermore, a quote of events are probably determined mainly by the aortic navigation and carotid catheterization that are a source of cerebral embolization independently from the carotid stent used. 31 On the contrary, the low rate of stroke in symptomatic patients (included in this meta-analysis), treated with DLMM can be justified by the design of the stents and the low risk of PP or micro-embolization after stent apposition. 32 In Montorsi et al’s 23 RCT, we observed a comparison of the DLMM Roadsaver stent with the FGS Carotid Wallstent (CW) (Boston Scientific, Santa Clara, California) in association with either distal embolic protection with the FilterWire (FW) device (Boston Scientific) or proximal protection with the Mo.Ma Ultra device (Medtronic, Santa Rosa, California) in patients with lipid-rich carotid plaques. A total of 104 consecutive patients with carotid artery stenosis were randomized to CAS with FW+Roadsaver (group 1, n = 27), FW+CW (group 2, n = 25), Mo.Ma+Roadsaver (group 3, n = 27), or Mo.Ma+CW (group 4, n = 25). 23 Study included all de novo carotid artery stenosis either symptomatic (Doppler PSV ≥130 cm/s and >50% stenosis) or asymptomatic (Doppler PSV ≥230 cm/s and >70% stenosis). 23 The primary endpoint was the number of MESs on transcranial Doppler among groups in the following CAS steps: (1) and (2) target vessel access, (3) lesion wiring, (4) pre-dilation, (5) stent crossing, (6) stent deployment, (7) stent dilation, and (8) device retrieval and deflation. 23 In this RCT, 23 the DLMM Roadsaver was associated with a significantly lower MES count than with the FGS CW. Interestingly, spontaneous MES occurred in 29% of patients. 23 This finding is likely due to PP-induced debris embolization between the last CAS phases. 23 Although not statistically significant, the risk for spontaneous MES was increased by 80% in patents with the CW compared with the Roadsaver. 23 These results further support the role of PP as a potential source of ischemic events in the late phase of CAS, fueling the role for a double-mesh stent for optimal plaque containment and reduction of PP. 23
Nerla et al 16 found PP rate (by optical coherence tomography) as low as 7.7% in a small subgroup of patients who underwent CAS with the DLMM Roadsaver stent. It is interesting to note that most patients had evidence of PP between the 2 stent meshes, as proof of the protective effect of double mesh. 16 The DLMM Roadsaver stent significantly decreased the rate of MES compared with the FGS (CW), especially when combined with the Mo.Ma system. 16 Squizzato et al 26 suggested that a DLMM stent design is overall associated with a lower rate of intraoperative embolization and a lower embolic filter debris load, compared with OC stent and CC stent. This seems to be the consequence of a lower embolic filter debris load in the micromesh stent group in the case of hypoechogenic plaques (P < .001), plaque length >15 mm (P = .015), and presence of preoperative ipsilateral cerebral ischemic lesions (P < .001). 26 A possible explanation is that these plaque characteristics identify a subgroup of carotid stenotic lesions that are more prone to embolization during stenting procedures. 26 Hypoechogenic carotid lesions are typically associated with the presence of a soft component, and previous studies33,34 had described the association between echolucency and the amount of embolic material captured by the filter. In addition, the presence of preoperative ischemic cerebral lesions may be considered a sign of silent embolization from an unstable asymptomatic carotid stenosis35,36 that poses a greater risk of embolization also in the perioperative period.33,37 Differently, the length of the lesion is not associated with the quality of the atheroma, but is directly linked to the surface of the carotid plaque; therefore, longer plaques carry an higher embolic risk due to the wider area of embolic source. 26 This DLMM stents has a peculiar configuration derived from the idea that a smaller cell area would protect from perioperative adverse events, 3 and in fact the resulting cell area (75–500 µm for the Roadsaver stent) is significantly smaller than with traditional OC (5.89 mm2 for the Precise) and CC (1.08 mm2 for the Wallstent) stents. 5 This design is specifically intended to provide an optimal plaque scaffolding and prevent PP through the struts of the stent, which has been associated with both intraoperative and perioperative embolization in patients undergoing CAS. 26 Squizzato et al 26 found the use of DLMM stent (Roadsaver for this study) seems to be associated with a lower embolization rate and embolic filter debris load, especially in hypoechogenic and long plaques and in patients with preoperative evidence of asymptomatic ischemic cerebral lesion. It is important clarify that the occurrence of new magnetic resonance imaging lesions, as well as the embolic filter debris load, represents a surrogate end point of Squizzato et al 26 study and only a minority of patients with new magnetic resonance imaging lesion or filter embolization develop clinically evident neurological complications. On the contrary, the same group of University of Padua reported 26 significant relationship existing between the amount of embolic filter debris and the risk of clinically evident neurological complications. Despite the significant difference in embolic filter debris load, the clinical outcomes in terms of neurological complications were similar between the 3 aforementioned group of stents and further studies are required to clarify the impact of stent design on intraoperative or postoperative stroke. 26 Moreover, in Roadsaver study, Langhoff et al 9 found specific types of high-risk anatomies did not significantly influence the observed outcomes: higher numbers of anatomical complexities did not seem to associate with an elevated risk of either 30-day MAEs or any stroke. 9 These findings suggested that DLMM (Roadsaver in this study) use in CAS may mitigate the risks associated with complex vascular anatomies. 9 Mazurek et al’s 1 review and meta-analysis of the clinical data of 68 422 patients (112 studies) treated using FGS or DLMM stent (C-Guard and Roadsaver) demonstrated that outcomes at 30 days (death/stroke/myocardial infarction) were significantly improved for pooled DLMM in relation to FGS. The benefit was present for new-generation stents against both OC and CC FGS. 38 Mazurek et al 1 suggested that the 2 DLMM stent types significantly differ (both in their outcomes related to FGS and for outcomes within the new generation carotid stent group) indicating lack of any carotid “mesh-stent” class effect, but this finding was not evident in other contemporary meta-analyses. In fact, in Pini et al 33 CAS with DLMM stent is associated with a low rate of 30-day stroke in both symptomatic (1.9%) and asymptomatic (1.5%) patients and the DLMM stent (C-Guard or Roadsaver) did not affect the 30-day stroke rate. 33 In addition, in this meta-analysis, acute DLMM carotid stent occlusion was separately evaluated. 33 Some authors considered the acute DLMM stent occlusion as a specific complication of the design of these stents. 33 The rate of DLMM stent occlusion reported in Pini et al’s 33 meta-analysis is 0.8% over a total of 930 patients. These results are strikingly different from the data of Runck et al 39 and Yilmaz et al 40 who reported a 24% and a 45% DLMM stent thrombosis rate in the treatment of acute strokes, respectively (including tandem lesions). The DLMM thrombosis rate reported by Pini et al 33 seems to be similar to the results reported by Moulakakis et al 41 (who described a series of 674 CAS with standard stents, having 4 cases (0.6%) of acute thrombosis, possibly secondary to carotid dissections and overlapping of a second stent). 31
Our results seem in line with Pini et al 33 results, with a low 30-day stroke rate and low 30-day death rate, even though no statistical differences emerged in comparison with FGS. Moreover, no statistical differences emerged from the meta-analysis regarding the ISR rate between the 2 different types of DLMM stents.
Limits
The present meta-analysis has some limitations, first, the retrospective nature of all studies and the absence of a standardized neurological evaluation, leading to a possible underestimation of stroke rates. The experience and the volume of the centers have a determinant role in the CAS outcome, with a reduction of neurologic events in high experience centers; however, it was not possible to investigate this moderator in our meta-analysis. 42 On the contrary, a recent Roadsaver study 43 demonstrated that although there may be slight differences in patient selection and procedural preferences across different specialties, outcomes achieved in real-world practice remain similar when performing contemporary CAS procedures using modern devices and techniques. 43
A key limitation of this study is the small number of comparative studies eligible for quantitative meta-analysis. Although 22 studies were identified overall, only 5 provided sufficiently homogeneous and extractable comparative data. The limited number of data sets reduces the stability of pooled estimates, may mask true variability between studies, and increases the risk that the meta-analytic findings reflect early trends rather than definitive evidence. Therefore, the results of the pooled analyses should be interpreted cautiously and considered exploratory signals that require confirmation in larger, high-quality comparative or randomized studies. Although we considered performing a sensitivity analysis including the randomized trial, this was not feasible due to the absence of directly comparable clinical endpoints and the use of a surrogate primary outcome. Any pooled estimate combining physiological and clinical endpoints would have lacked interpretability and methodological validity. For this reason, the RCT was incorporated solely at the qualitative level. The ISR analysis was characterized by very high heterogeneity, reflecting substantial methodological differences across studies. In-stent restenosis definitions were inconsistent, imaging modalities varied (duplex ultrasound vs CTA vs angiography), PSV thresholds were non-uniform, and follow-up durations differed across centers. These factors likely contributed substantially to the variability in reported ISR rates. The marked variability in ISR definitions, PSV thresholds, imaging modalities, and follow-up intervals across studies is a major contributor to the high heterogeneity observed in the ISR meta-analysis. This limits the interpretability of pooled restenosis estimates and underscores the exploratory character of the findings. Finally, the certainty of evidence derived from the included studies is intrinsically low. The vast majority of studies were observational, often single center, with limited control for baseline differences and inconsistent follow-up protocols. Only 1 RCT was available, but its design and outcomes were incompatible with pooling. Based on the GRADE domains—risk of bias, inconsistency, indirectness, and imprecision—the overall certainty of evidence for all pooled outcomes is low. Therefore, the results of this meta-analysis should be regarded as hypothesis-generating and interpreted with appropriate caution.
Conclusions
This study suggests that transfemoral CAS with the Roadsaver DLMM stent is associated with low 30-day stroke and death rates in European practice. The pooled comparisons did not detect statistically significant differences versus FGSs or between the 2 DLMM stent types in terms of 30-day outcomes or 12-month restenosis. However, these findings do not imply equivalence. Given the observational nature of most included studies, the variability in ISR definitions, and the small number of comparative data sets, the analyses lack the power and methodological rigor required to draw confirmatory conclusions about comparative performance. The present results should therefore be interpreted as hypothesis-generating, underscoring the need for well-designed prospective comparative studies and RCTs.
Supplemental Material
sj-docx-1-jet-10.1177_15266028261453269 – Supplemental material for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis
Supplemental material, sj-docx-1-jet-10.1177_15266028261453269 for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis by Giovanni Mastrangelo, Giuseppe Di Martino, Antonino Marzullo, Vincenzo Palazzo and Pierluigi Di Sebastiano in Journal of Endovascular Therapy
Supplemental Material
sj-docx-2-jet-10.1177_15266028261453269 – Supplemental material for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis
Supplemental material, sj-docx-2-jet-10.1177_15266028261453269 for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis by Giovanni Mastrangelo, Giuseppe Di Martino, Antonino Marzullo, Vincenzo Palazzo and Pierluigi Di Sebastiano in Journal of Endovascular Therapy
Supplemental Material
sj-docx-3-jet-10.1177_15266028261453269 – Supplemental material for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis
Supplemental material, sj-docx-3-jet-10.1177_15266028261453269 for Ten Years of European Experience With Roadsaver Carotid Stent: A Systematic Review of Literature and Exploratory Meta-Analysis by Giovanni Mastrangelo, Giuseppe Di Martino, Antonino Marzullo, Vincenzo Palazzo and Pierluigi Di Sebastiano in Journal of Endovascular Therapy
Footnotes
Acknowledgements
The authors declare that they used ChatGPT-5.1 to assist in reviewing the manuscript. In particular, it was used to generate supplementary materials: to specify the actual follow-up length for ISR assessment per study and clarify whether variations in follow-up time were present; about high heterogeneity in the ISR analysis, to clarify that due to the small number of available comparative studies, meaningful sensitivity analyses—such as exclusion of outlier studies, stratification by imaging modality, or meta-regression—were not feasible; and create a structured presentation of the risk-of-bias evaluation for each included study. In addition, this generative AI was used to assist in reviewing the manuscript for grammar and style.
Authors’ Note
This work was presented as e-poster in XXIII National Congress of Italian Society for Vascular and Endovascular Surgery (SICVE) (October 13-15, 2025, Padua, Italy) and as oral communication in HOW TO DO IT (HTDI) 2024 in Milan.
Ethical Considerations
The systematic review and meta-analysis were performed according to the Cochrane Collaboration recommendations (see Higgins and Thompson10). A rigorous protocol was established before the analyses, concerning all the objectives, inclusion and exclusion criteria, primary and secondary outcomes, and synthesis methods.
Author Contributions
G.M. contributed to conceptualization, data curation, funding acquisition, investigation, methodology, project administration, writing—original draft, and writing—review and editing. G.D.M. contributed to formal analysis, writing—original draft, and writing—review and editing. A.M. contributed to investigation, visualization, and writing—review and editing. V.P. contributed to supervision and writing—review and editing. P.D.S. contributed to supervision.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: G.M. received a grant for this research by Terumo-Italia.
Declaration of Conflicting Interests
The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: G.M. declared to have perceived a research grant by Terumo-Italia.
Supplemental Material
Supplemental material for this article is available online.
Tracked Changes or Comments Where the Poster’s Name Is Listed
None.
References
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