Proximal protection with the Gore PAES can reduce DWI lesion size in high-grade stenosis during carotid stenting

Outcomes in acute carotid-related stroke eligible for mechanical reperfusion: SAFEGUARD-STROKE Registry

BACKGROUND

Carotid-related strokes (CRS) are largely unresponsive to intravenous thrombolysis and are often large and disabling. Little is known about contemporary CRS referral pathways and proportion of eligible patients who receive emergency mechanical reperfusion (EMR).

METHODS

Referral pathways, serial imaging, treatment data, and neurologic outcomes were evaluated in consecutive CRS patients presenting over 18 months in catchment area of a major carotid disease referral center with proximal-protected CAS expertise, on-site neurology, and stroke thrombectomy capability (Acute Stroke of CArotid Artery Bifurcation Origin Treated With Use oF the MicronEt-covered CGUARD Stent - SAFEGUARD-STROKE Registry; companion to SAFEGUARD-STROKE Study NCT05195658).

RESULTS

Of 101 EMR-eligible patients (31% i.v.-thrombolyzed, 39.5% women, age 39-89 years, 94.1% ASPECTS 9-10, 90.1% pre-stroke mRS 0-1), 57 (56.4%) were EMR-referred. Referrals were either endovascular (Comprehensive Stroke Centre, CSC, 21.0%; Stroke Thrombectomy-Capable CAS Centre, STCC, 70.2%) or to vascular surgery (VS, 1.8%), with >1 referral attempt in 7.0% patients (CSC/VS or VS/CSC or CSC/VS/STCC). Baseline clinical and imaging characteristics were not different between EMR-treated and EMR-untreated patients. EMR was delivered to 42.6% eligible patients (emergency carotid surgery 0%; STCC rejections 0%). On multivariable analysis, non-tandem CRS was a predictor of not getting referred for EMR (OR 0.36; 95%CI 0.14-0.93, P=0.03). Ninety-day neurologic status was profoundly better in EMR-treated patients; mRS 0-2 (83.7% vs. 34.5%); mRS 3-5 (11.6% vs. 53.4%), mRS 6 (4.6% vs. 12.1%); P<0.001 for all.

CONCLUSIONS

EMR-treatment substantially improves CRS neurologic outcomes but only a minority of EMR-eligible patients receive EMR. To increase the likelihood of brain-saving treatment, EMR-eligible stroke referral and management pathways, including those for CSC/VS-rejected patients, should involve stroke thrombectomy-capable centres with endovascular carotid treatment expertise.

Carotid artery revascularization using second generation stents versus surgery: a meta-analysis of clinical outcomes

INTRODUCTION

Meta-analyses and emerging randomized data indicate that second-generation ('mesh') carotid stents (SGS) may improve outcomes versus conventional (single-layer) stents but clinically-relevant differences in individual SGS-type performance have been identified. No comparisons exist for SGS versus carotid endarterectomy (CEA).

EVIDENCE ACQUISITION

Thirty-day death (D), stroke (S), myocardial infarction (M), and 12-month ipsilateral stroke and restenosis in SGS studies were meta-analyzed (random effect model) against CEA outcomes. Eligible studies were identified through PubMed/EMBASE/COCHRANE. Forest plots were formed for absolute adverse evet risk in individual studies and for relative outcomes with each SGS deign versus contemporary CEA outcomes as reference. Meta-regression was performed to identify potential modifiers of treatment modality effect.

EVIDENCE SYNTHESIS

Data were extracted from 103,642 patients in 25 studies (14 SGS-treated, 41% symptomatic; nine randomized controlled trial (RCT)-CEA-treated, 37% symptomatic; and two Vascular Quality Initiative (VQI)-CEA-treated, 23% symptomatic). Casper/Roadsaver and CGuard significantly reduced DSM versus RCT-CEA (-2.70% and -2.95%, P<0.001 for both) and versus VQI-CEA (-1.11% and -1.36%, P<0.001 for both). Gore stent 30-day DSM was similar to RCT-CEA (P=0.581) but increased against VQI-CEA (+2.38%, P=0.033). At 12 months, Casper/Roadsaver ipsilateral stroke rate was lower than RCT-CEA (-0.75%, P=0.026) and similar to VQI-CEA (P=0.584). Restenosis with Casper/Roadsaver was +4.18% vs. RCT-CEA and +4.83% vs. VQI-CEA (P=0.005, P<0.001). CGuard 12-month ipsilateral stroke rate was similar to VQI-CEA (P=0.850) and reduced versus RCT-CEA (-0.63%, P=0.030); restenosis was reduced respectively by -0.26% and -0.63% (P=0.033, P<0.001). Twelve-month Gore stent outcomes were overall inferior to surgery.

CONCLUSIONS

Meta-analytic integration of available clinical data indicates: 1) reduction in stroke but increased restenosis rate with Casper/Roadsaver, and 2) reduction in both stroke and restenosis with CGuard MicroNET-covered stent against contemporary CEA outcomes at 30 days and 12 months used as a reference. This may inform clinical practice in anticipation of large-scale randomized trials powered for low clinical event rates (PROSPERO-CRD42022339789).

Carotid stenting: Does stent design matter?

BACKGROUND

Carotid artery stenting (CAS) is considered an important tool in carotid revascularization. Carotid artery stenting is usually performed by using self-expandable stent with different designs. The stent design influences many physical characteristics. Also, it may affect the complication rate with special relevance to perioperative stroke, hemodynamic instability, and late restenosis.

METHODS

This study comprised all consecutive patients who underwent carotid artery stenting for atherosclerotic carotid stenosis from March 2014 to May 2021. Both symptomatic patient and asymptomatic patients were included. Patients with a symptomatic carotid stenosis of ≥50% or asymptomatic carotid stenosis of ≥60% were selected for carotid artery stenting . Patients with fibromuscular dysplasia and acute or unstable plaque were not included. Variables of clinical relevance were tested in multivariable analysis using binary logistic regression model.

RESULTS

A total of 728 patients were enrolled. The majority of this cohort was asymptomatic (578/728, 79.4%), while 150/728 (20.6%) were symptomatic. The mean degree of carotid stenosis was 77.82 ± 4.73%, with a mean plaque length of 1.76 ± 0.55 cm. A total of 277 (38%) patients were treated with Xact® Carotid Stent System. Successful carotid artery stenting was achieved in 698 (96%) of patients. Of these patients, stroke rate in symptomatic patients was nine (5.8%), while in asymptomatic patients was 20 (3.4%). In a multivariable analysis, the open-cell carotid stent was not associated with a differential risk for combined acute and sub-acute neurologic complications as compared with closed-cell stents. Patients treated with open cell stents had a significantly lower rate of procedural hypotension (P 0.0188) at bivariate analysis.

CONCLUSION

Carotid artery stenting is considered a safe alternative to CEA that can be used in selected average surgical risk patient. Different stent designs can affect the rate of major adverse events in carotid artery stenting patients, but further studies are necessary with avoiding different bias to study the effect of different stent designs.

Randomized Controlled Trial of Conventional Versus MicroNet-Covered Stent in Carotid Artery Revascularization

OBJECTIVES

The aim of this study was to compare procedure-related ipsilateral cerebral embolism with a conventional (Acculink, Abbott Vascular) versus a MicroNet-covered (CGuard, InspireMD) stent in carotid artery stenting (CAS).

BACKGROUND

The MicroNet-covered stent may reduce periprocedural cerebral embolism in CAS, but level 1 evidence is lacking.

METHODS

A total of 100 consecutive patients were randomized 1:1 to filter-protected CAS using the Acculink or the CGuard device. The study was powered for its primary endpoint of at least 50% reduction in ipsilateral diffusion-weighted magnetic resonance imaging lesion average volume 48 hours postprocedure (blinded external core laboratory analysis).

RESULTS

The baseline characteristics of the study groups were similar. Eighty-two (total volume = 18,212 mm³) diffusion-weighted magnetic resonance imaging postprocedural cerebral lesions occurred in 26 Acculink-treated patients and 45 lesions (total volume = 3,930 mm³; 78.4% reduction) in 25 CGuard-treated patients. New cerebral lesion average volume was 171 mm³ vs 73 mm³ (P = 0.017) per affected patient and 222 mm³ vs 84 mm³ (P = 0.038) per lesion (Acculink vs CGuard). In lesion-affected patients, the average sum of lesion volumes was 701 mm³ vs 157 mm³ (P = 0.007). The Acculink significantly increased the risk for multiple (≥5) cerebral lesions (relative risk: 7.8; 95% CI: 1.3-14.9; P = 0.021). At 30 days, new permanent (fluid-attenuated inversion recovery) lesion prevalence was 3:1 (P < 0.001), with total permanent lesion volume 7,474 mm³ vs 574 mm³ (92.3% reduction with the CGuard). There were 6 vs 0 new ipsilateral lesions (P = 0.030) and 2 versus 0 strokes.

CONCLUSIONS

The MicroNet-covered stent significantly reduced periprocedural and abolished postprocedural cerebral embolism in relation to a conventional carotid stent. This is consistent with the MicroNet-covered stent's sustained embolism prevention, translating into cerebral protection not only during but also after CAS. The present findings may influence decision making in carotid revascularization. (The SIBERIA Trial [Acculink™ Versus CGuard™]; NCT03488199).

Safety of Catheter Embolization of Pulmonary Arteriovenous Malformations-Evaluation of Possible Cerebrovascular Embolism after Catheter Embolization of Pulmonary Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia/Osler Disease by Pre- and Post-Interventional DWI

BACKGROUND

This paper aimed to prospectively evaluate the safety of embolization therapy of pulmonary arteriovenous malformations (PAVMs) for the detection of cerebral infarctions by pre- and post-interventional MRI. Method One hundred and five patients (male/female = 44/61; mean age 48.6+/-15.8; range 5-86) with pre-diagnosed PAVMs on contrast-enhanced MRA underwent embolization therapy. The number of PAVMs treated in each patient ranged from 1-8 PAVMs. Depending on the size and localization of the feeding arteries, either Nester-Coils or Amplatzer vascular plugs were used for embolization therapy. cMRI was performed immediately before, and at the 4 h and 3-month post-embolization therapy. Detection of peri-interventional cerebral emboli was performed via T2w and DWI sequences using three different b-values, with calculation of ADC maps. Results Embolization did not show any post-/peri-interventional, newly developed ischemic lesions in the brain. Only one patient who underwent re-embolization and was previously treated with tungsten coils that corroded over time showed newly developed, small, diffuse emboli in the post-interventional DWI sequence. This patient already had several episodes of brain emboli before re-treatment due to the corroded coils, and during treatment, when passing the corroded coils, experienced additional small, clinically inconspicuous brain emboli. However, this complication was anticipated but accepted, since the vessel had to be occluded distally. Conclusion Catheter-based embolization of PAVMs is a safe method for treatment and does not result in clinically inconspicuous cerebral ischemia, which was not demonstrated previously.

Silent brain infarcts on diffusion-weighted imaging after carotid revascularisation: A surrogate outcome measure for procedural stroke? A systematic review and meta-analysis

Aim

To investigate whether lesions on diffusion-weighted imaging (DWI+) after carotid artery stenting (CAS) or endarterectomy (CEA) might provide a surrogate outcome measure for procedural stroke.

Materials and Methods

Systematic MedLine® database search with selection of all studies published up to the end of 2016 in which DWI scans were obtained before and within seven days after CAS or CEA. The correlation between the underlying log odds of stroke and of DWI+ across all treatment groups (i.e. CAS or CEA groups) from included studies was estimated using a bivariate random effects logistic regression model. Relative risks of DWI+ and stroke in studies comparing CAS vs. CEA were estimated using fixed-effect Mantel-Haenszel models.

Results

We included data of 4871 CAS and 2099 CEA procedures (85 studies). Across all treatment groups (CAS and CEA), the log odds for DWI+ was significantly associated with the log odds for clinically manifest stroke (correlation coefficient 0.61 (95% CI 0.27 to 0.87), p = 0.0012). Across all carotid artery stenting groups, the correlation coefficient was 0.19 (p = 0.074). There were too few CEA groups to reliably estimate a correlation coefficient in this subset alone. In 19 studies comparing CAS vs. CEA, the relative risks (95% confidence intervals) of DWI+ and stroke were 3.83 (3.17-4.63, p < 0.00001) and 2.38 (1.44-3.94, p = 0.0007), respectively.

Discussion

This systematic meta-analysis demonstrates a correlation between the occurrence of silent brain infarcts on diffusion-weighted imaging and the risk of clinically manifest stroke in carotid revascularisation procedures.

Conclusion

Our findings strengthen the evidence base for the use of DWI as a surrogate outcome measure for procedural stroke in carotid revascularisation procedures. Further randomised studies comparing treatment effects on DWI lesions and clinical stroke are needed to fully establish surrogacy.

One swallow does not a summer make but many swallows do: accumulating clinical evidence for nearly-eliminated peri-procedural and 30-day complications with mesh-covered stents transforms the carotid revascularisation field

Atherosclerotic carotid artery stenosis (CS) continues to be a common cause of acute ischaemic stroke. Optimised medical therapy (OMT), the first-line treatment modality in CS, may reduce or delay - but it does not abolish - CS-related strokes. As per current AHA/ASA and ESC/ESVS/ESO guidelines, carotid artery stenting (CAS) is a less-invasive alternative to carotid endarterectomy (CEA) for CS revascularisation in primary and secondary stroke prevention. Ten-year follow-up from the CREST trial in patients with symptomatic and asymptomatic CS confirmed equipoise of CAS and CEA in the primary endpoint. Nevertheless CAS - using a widely open-cell, first-generation stent and first-generation (distal/filter) neuroprotection - has been criticised for its relative excess of (mostly minor) strokes by 30 days, a significant proportion of which were post-procedural. Atherosclerotic plaque protrusion through conventional carotid stent struts, confirmed on intravascular imaging, has been implicated as a leading mechanism of the relative excess of strokes with CAS vs. CEA, including delayed strokes with CAS. Different designs of mesh-covered carotid stents have been developed to prevent plaque prolapse. Several multi-centre/multi-specialty clinical studies with CGurad MicroNet-Covered Embolic Prevention Stent System (EPS) and RoadSaver/Casper were recently published and included routine DW-MRI cerebral imaging peri-procedurally and at 30 days (CGuard EPS). Data from more than 550 patients in mesh-covered carotid stent clinical studies to-date show an overall 30-day complication rate of ~1% with near-elimination of post-procedural events. While more (and long-term) evidence is still anticipated, these results - taken together with optimised intra-procedural neuroprotection in CAS (increased use of proximal systems including trans-carotid dynamic flow reversal) and the positive 12-month mesh-covered stent data reports in 2017 - are transforming the carotid revascularisation field today. Establishing effective algorithms to identify the asymptomatic subjects at stroke risk despite OMT, and large-scale studies with mesh-covered stents including long-term clinical and duplex ultrasound outcomes, are the next major goals.

Laboratory-Based Markers as Predictors of Brain Infarction During Carotid Stenting: a Prospective Study

AIM

New ischemic lesions in the brain can be detected in approximately 50% of patients undergoing carotid artery stenting (CAS). We wished to discover the laboratory-based predictors of new infarctions in the brain after CAS.

METHODS

All consecutive patients with internal carotid artery stenosis of ≥70% with indication for CAS were enrolled in a prospective study for 16 months. All patients used dual antiplatelet therapy for ≥7 days before CAS. Neurologic examination and magnetic resonance imaging (MRI) of the brain were undertaken before and at 24 h after CAS. Samples of venous blood were collected at ＜24 h before CAS for the evaluation of hematology, reticulocytes, coagulation markers (PT, APTT, Fbg, Clauss), vWF antigen, PAI-1 activity, PAI-1 polymorphism 4G/5G, and the multiplate (aspirin and clopidogrel) resistance test. Blood samples for the assessment of anti-Xa activity were collected during CAS. Differences in the values of laboratory markers between patients with and without new ischemic lesions of the brain on control MRI were evaluated.

RESULTS

The cohort comprised 81 patients (53 males; mean age, 67.3±7.2 years). New ischemic infarctions in the brain on control MRI were found in 46 (56.8%) patients. Three of seven patients with resistance to aspirin or clopidogrel had a new ischemic infarction in the brain. No significant differences for particular markers were found between patients with and without an ischemic lesion in the brain.

CONCLUSION

A high risk of a new ischemic infarction in the brain was detected in patients undergoing CAS, but a laboratory-based predictor of such an infarction could not be identified.

High-Risk Factors in Symptomatic Patients Undergoing Carotid Artery Stenting With Distal Protection

BACKGROUND:

Demographics and vascular anatomy may play an important role in predicting periprocedural complications in symptomatic patients undergoing carotid artery stenting (CAS).

OBJECTIVE:

To predict factors associated with increased risk of complications in symptomatic patients undergoing CAS and to devise a CAS scoring system that predicts such complications in this patient population.

METHODS:

A retrospective study was conducted that included patients who underwent CAS for symptomatic carotid stenosis during a 3-year period. Demographics and anatomic characteristics were subsequently correlated with 30-day outcome measures.

RESULTS:

A total of 221 patients were included in the study. The cumulative rate of periprocedural complications was 7.2%, including stroke (3.2%), myocardial infarction (3.2%), and death (1.4%). Renal disease increased the risk of all complications. National Institutes of Health Stroke Scale score ≥10 at presentation, difficult femoral access, and diseased calcified aortic arch increased the risk of stroke and all complications. Type III aortic arch correlated with increased risk of stroke. Pseudo-occlusion and concentric calcification of the carotid artery increased the risk of myocardial infarction, death, and all complications. Carotid tortuosity and anatomy hostile to the deployment of distal protection devices increased the risk of stroke, myocardial infarction, death, and all complications.

CONCLUSION:

Our results suggest that CAS should be avoided in patients with multiple anatomic risk factors. High presenting National Institutes of Health Stroke Scale score and renal disease also increase the complication risk. The CAS scoring system devised here is simple, reproducible, and clinically valuable in predicting complications risk in symptomatic patients undergoing CAS.