Carotid stent-supported angioplasty: a neurovascular intervention to prevent stroke

Stroke risk management in carotid atherosclerotic disease: a clinical consensus statement of the ESC Council on Stroke and the ESC Working Group on Aorta and Peripheral Vascular Diseases

Carotid atherosclerotic disease continues to be an important cause of stroke, often disabling or fatal. Such strokes could be largely prevented through optimal medical therapy and carotid revascularization. Advancements in discovery research and imaging along with evidence from recent pharmacology and interventional clinical trials and registries and the progress in acute stroke management have markedly expanded the knowledge base for clinical decisions in carotid stenosis. Nevertheless, there is variability in carotid-related stroke prevention and management strategies across medical specialities. Optimal patient care can be achieved by (i) establishing a unified knowledge foundation and (ii) fostering multi-specialty collaborative guidelines. The emergent Neuro-Vascular Team concept, mirroring the multi-disciplinary Heart Team, embraces diverse specializations, tailors personalized, stratified medicine approaches to individual patient needs, and integrates innovative imaging and risk-assessment biomarkers. Proposed approach integrates collaboration of multiple specialists central to carotid artery stenosis management such as neurology, stroke medicine, cardiology, angiology, ophthalmology, vascular surgery, endovascular interventions, neuroradiology, and neurosurgery. Moreover, patient education regarding current treatment options, their risks and advantages, is pivotal, promoting patient's active role in clinical care decisions. This enables optimization of interventions ranging from lifestyle modification, carotid revascularization by stenting or endarterectomy, as well as pharmacological management including statins, novel lipid-lowering and antithrombotic strategies, and targeting inflammation and vascular dysfunction. This consensus document provides a harmonized multi-specialty approach to multi-morbidity prevention in carotid stenosis patients, based on comprehensive knowledge review, pinpointing research gaps in an evidence-based medicine approach. It aims to be a foundational tool for inter-disciplinary collaboration and prioritized patient-centric decision-making.

Neurosurgical Breakthroughs of the Last 50 Years: A Historical Journey Through the Past and Present

This article presented the author's historical perspective on 25 of the most significant neurosurgical breakthrough events of the last 50 years. These breakthroughs have advanced neurosurgical patient care and management. They have improved the management of aneurysms, arteriovenous malformations, tumors, stroke, traumatic brain injury, movement disorders, epilepsy, hydrocephalus, and spine pathologies. Neurosurgery has evolved through research, innovation, and technology. Several neurosurgical breakthroughs were achieved using neuroendoscopy, neuronavigation, radiosurgery, endovascular techniques, and refinements in computer technology. With these breakthroughs, neurosurgery did not change; it just progressed. Neurosurgery should continue its progress through research to obtain new knowledge for the benefit of our patients.

Systematic Review and Meta-Analysis of Transradial Access for Carotid Artery Stenting

There is an increasing number of studies on the transradial approach (TRA) for carotid artery stenting. We aimed to summarize the published data on TRA vs the transfemoral approach (TFA). We searched Science Direct, Embase, PubMed, and Web of Science databases for the relevant literature. Primary outcomes included surgical success and cardiovascular and cerebrovascular complication rates; secondary outcomes included the rates of vascular access-related and other complications. We also compared the crossover rate, success rate, and complications between TRA and TFA carotid stenting. This is the first such meta-analysis regarding TRA and TFA. Twenty studies on TRA carotid stenting were included (n = 1300). Among 19 studies, the success rate of TRA carotid stenting was .951 (95% confidence interval [CI]: .926-.975); death rate was .022 (.011-.032); stroke rate was .005 (.001-.008); radial artery occlusion rate was .008 (.003-.013); and forearm hematoma rate was .003 (-.000 to .006). Among 4 studies comparing TRA and TFA, the success rate was lower (odds ratio: .02; 95% CI: .00-.23) and crossover rate was higher (odds ratio: 40.16; 95% CI: 4.41-365.73) with TRA. Thus, transradial neuro-interventional surgery has a lower success rate than TFA.

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).

History of Carotid Artery Reconstruction around the World and in Japan

Since ancient times, physicians have been aware of correlations between the carotid artery and consciousness; however, carotid stenosis was only recently identified as the cause of atherothrombotic ischemic stroke. In 1658, Wepfer described the first suggestion of a link between symptoms of cerebral arterial insufficiency and carotid pathology. In 1951, Fisher reported details of the symptoms and pathological findings and emphasized that cervical atheromatous lesions induced cerebral infarction with various symptoms. The beginning of carotid artery surgery was ligation of the carotid artery for neck or head injury, but surgeons were aware that this operation induced cerebral symptoms due to lack of blood supply. Carotid endarterectomy (CEA) was first reported by Eastcott et al. in 1954, and in Japan, Kimoto performed a successful CEA in 1962. In 1979, percutaneous transluminal angioplasty (PTA) was performed for patients with fibromuscular dysplasia, and then, carotid artery stenting (CAS) was first performed in 1989 by Mathias. In Japan, Kuwana et al. were the first to perform carotid PTA, in 1981, whereas Yamashita et al. performed the first CAS in 1997. Yoshimura et al. proposed staged carotid stenting to prevent hyperperfusion syndrome. Some issues in carotid reconstruction are still debated today, which include conventional (standard) CEA versus the eversion technique, CEA versus CAS versus medical therapy, and medical economic problems. In the future, we must continue to develop more effective, safer, and less expensive therapeutic methods to prevent carotid stroke, carrying on the efforts of the ancient peoples who pioneered this research.

Commentary on a case report and literature review of acute carotid stent thrombosis

In this commentary on the article entitled “Acute carotid stent thrombosis: A case report and literature review”, the key points of the article are discussed. Acute carotid stent thrombosis (ACST) in the setting of carotid artery stenting (CAS) represents a rare but potentially catastrophic event. There is a wide range of treatment options available, including carotid endarterectomy, which is generally recommended for cases of refractory ACST. While there is no standard treatment regimen, dual antiplatelet therapy is typically recommended both before and after CAS to reduce risk of ACST.

Carotid artery stenting: still burdened by early trial results

The early randomized trial experience (CAVATAS, SPACE, EVA-3S, ICSS) comparing carotid artery stenting (CAS) and carotid endarterectomy (CEA) has been burdened by the limited experience of the interventionalists performing CAS. The periprocedural stroke excess with CAS observed in those trials has ever since affected carotid revascularization, especially in symptomatic carotid disease. Accordingly, no trial dedicated to this patient population has followed. In asymptomatic carotid disease, CREST, ACT-1 and ACST-2 have shown an equivalence in terms of combined periprocedural events as well as long-term protection from ipsilateral stroke or repeat revascularization between the two techniques. The management of patients with carotid stenosis should be multidisciplinary and decision to pursue medical management or proceed to revascularization in an individual patient should be based on his estimated stroke risk on medical management and his suitability for CEA and CAS. Since the majority of patients with carotid stenosis may qualify for both techniques, patient's perspective should be central in decision making.

Investigation into the role of Stmn2 in vascular smooth muscle phenotype transformation during vascular injury via RNA sequencing and experimental validation

This study examined the effects of Stmn2 on phenotype transformation of vascular smooth muscle in vascular injury via RNA sequencing and experimental validation. Total RNA was extracted for RNA sequencing after 1, 3 and 5 days of injury to screen the differentially expressed genes (DEGs). Western blot was used to detect the protein expression of Stmn2 and its associated targets. The morphological changes of carotid arteries in rats were examined by hematoxylin and eosin (H&E) staining. The expression of vascular smooth muscle cell (VSMC) phenotype markers smooth muscle alpha-actin (α-SMA), vimentin and OPN were detected by immunohistochemistry. DEGs were related to the extracellular matrix and other cell components outside the plasma membrane. They were associated with protein binding, cytoskeleton protein binding, signal receptor binding and other molecular functions, actin cytoskeleton regulation and other Kyoto Encyclopedia of Genes and Genomes pathways. Stmn2 was identified as the hub gene of actin cytoskeleton pathway and vascular disease, and its expression followed the trend of decreasing initially and increasing afterwards during the progress of vascular injury. Western blot assay showed that the expression of Stmn2 and Tubulin decreased immediately after vascular injury; Stmn2 overexpression significantly up-regulated the expression of osteopontin and α-SMA and vimentin in VSMCs. The results of morphology analysis and immunostaining also showed that Stmn2 overexpression promoted the intima thickening and enhanced the proliferating cell nuclear antigen expression in the injured vascular tissues. In conclusion, our results implied that Stmn2 may play a potential role in vascular injury, which may be associated with VSMC phenotype transformation. Further studies are warranted to determine detailed molecular mechanisms of Stmn2 in vascular injury.

Carotid artery stenosis – Current evidence and treatment recommendations

Background:

Carotid artery stenosis is an important cause for stroke. Carotid endarterectomy (CEA) reduces the risk of stroke in patients with symptomatic carotid stenosis and to some extent in patients with asymptomatic carotid stenosis. More than 20 years ago, carotid artery stenting (CAS) emerged as an endovascular treatment alternative to CEA.

Objective and Methods:

This review summarises the available evidence from randomised clinical trials in patients with symptomatic as well as in patients with asymptomatic carotid stenosis.

Results:

CAS is associated with a higher risk of death or any stroke between randomisation and 30 days after treatment than CEA (odds ratio (OR) = 1.74, 95% CI 1.3 to 2.33, p < 0.0001). In a pre-defined subgroup analysis, the OR for stroke or death within 30 days after treatment was 1.11 (95% CI 0.74 to 1.64) in patients <70 years old and 2.23 (95% CI 1.61 to 3.08) in patients ≥70 years old, resulting in a significant interaction between patient age and treatment modality (interaction p = 0.007). The combination of death or any stroke up to 30 days after treatment or ipsilateral stroke during follow-up also favoured CEA (OR = 1.51, 95% CI 1.24 to 1.85, p < 0.0001). In asymptomatic patients, there is a non-significant increase in death or stroke occurring within 30 days of treatment with CAS compared to CEA (OR = 1.72, 95% CI 1.00 to 2.97, p = 0.05). The risk of peri-procedural death or stroke or ipsilateral stroke during follow-up did not differ significantly between treatments (OR = 1.27, 95% CI 0.87 to 1.84, p = 0.22).

Discussion and Conclusion:

In symptomatic patients, randomised evidence has consistently shown CAS to be associated with a higher risk of stroke or death within 30 days of treatment than CEA. This extra risk is mostly attributed to an increase in strokes occurring on the day of the procedure in patients ≥70 years. In asymptomatic patients, there may be a small increase in the risk of stroke or death within 30 days of treatment with CAS compared to CEA, but the currently available evidence is insufficient and further data from ongoing randomised trials are needed.

Carotid stenosis, stroke, and carotid artery revascularization

Atherosclerotic disease of the carotid artery places patients at risk of ischemic stroke and consequently is a target of medical, endovascular and open surgical management. Various imaging modalities are used to characterize anatomy/severity of carotid disease and justify intervention, each having advantages and disadvantages. Carotid revascularization techniques including carotid artery stenting, carotid endarterectomy, and transcarotid artery revascularization vary in invasiveness and are not equally suitable for certain subsets of patients. As such, providing quality care for patients with carotid disease requires a multidisciplinary team of experts in clinical diagnosis, image interpretation, medical management, endovascular intervention, and surgical treatment.

Stenting the carotid artery from radial access using a Simmons guide catheter

BACKGROUND

Carotid artery stenting (CAS) is a procedure for stroke prevention, usually done from femoral artery access. Reports of CAS using radial artery access have adopted techniques similar to those used for transfemoral CAS. Initial experience with a simpler and lower profile technique for transradial carotid stenting is described here.

METHODS

Of 55 consecutive elective CAS cases with standard (not bovine) arch anatomy performed during a 15 month time period by the same operator, 20 were selected for transradial treatment using a 6 F Simmons 2 guide catheter. This was a retrospective analysis of those initial 20 patients compared with the 35 patients treated with elective transfemoral CAS. The CAS database was reviewed for clinical indications, technique, procedure and fluoroscopy times, and clinical outcomes.

RESULTS

All procedures were technically successful (no crossovers). No patient had a decline in National Institutes of Health Stroke Scale score or modified Rankin Scale score within 30 days. Mean (95% CI) procedural times for transradial CAS were slightly higher than transfemoral CAS (29.4 (26.0 to 32.7) vs 23.8 (21.2 to 26.4) min, p=0.0098). Mean (95% CI) fluoroscopy times were also higher for transradial CAS compared with transfemoral CAS (9.6 (8.0 to 11.2) vs 6.4 (5.4 to 7.4), p=0.0006). One patient developed a radial artery pseudoaneurysm which required elective surgical repair.

CONCLUSION

Transradial carotid stenting using the described lower profile technique provides another effective option in the array of surgical procedures for the treatment of carotid artery stenosis. Relative procedural and fluoroscopy times may initially be longer compared with transfemoral carotid stenting for experienced CAS operators, although absolute differences are small.

The less invasive paradox, why carotid artery stenting is not suitable for the high-risk patient

Carotid artery stenosis causes significant morbidity and mortality accounting for approximately 8% of all ischaemic strokes. Carotid artery stenting (CAS) offers an endovascular alternative to carotid endarterectomy (CEA), suggested as a viable option in those deemed high-risk for open CEA due to comorbidities or operative technical considerations. A number of large randomised-controlled trials (RCTs) and meta-analysis comparing CAS vs. CEA in unselected patient populations support the conclusion that CAS is associated with a higher risk of stroke and CEA is associated with a higher risk of myocardial infraction. Initial promise for CAS in high-risk patients was demonstrated by The Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial that reported CAS was non-inferior to CEA. However, there is evidence to suggest age-related adverse outcome in patients undergoing CAS. There is limited evidence to suggest that CEA could be suitable even in patients deemed high-risk for medical or technical reasons. Further contemporary research on the use of CAS and CEA in high-risk patients is required to re-evaluate current guidelines and high-risk criterion. It is common for a composite outcome of death, ipsilateral stroke and MI which should be questioned as subsequent quality of life is likely to differ after suffering a stroke in comparison to MI. This literature review will discuss the current evidence for CAS and CEA interventions in unselected populations and high-risk patients with carotid disease requiring intervention.

In vitro investigation of chemical properties and biocompatibility of neurovascular braided implants

Braiding of Nitinol micro wires is an established technology for the manufacturing of fine-meshed neurovascular implants for tortuous vessel geometries. Electropolishing of wires before the braiding process has the potential to improve the in vitro behaviour in terms of thrombogenicity and endothelial cell proliferation. In this study, we present the first in vitro investigation of braided electropolished/blue oxide Nitinol samples in a blood flow loop, showing a significantly lower activation of the coagulation pathway (represented by the TAT III marker) and a tendency towards reduced platelet adhesion. Furthermore, we applied the same surface treatment on flat disks and measured protein adhesion as well as endothelial cell proliferation. We compared our results to non-electropolished samples with a native oxide surface. While platelet deposition was reduced on electropolished/blue oxide surface, a significant increase of endothelial cell seeding was observed. Investigation of inflammatory marker expression in endothelial cells provided divergent results depending on the marker tested, demanding closer investigation. Surface analysis using Auger electron spectroscopy revealed a thin layer mainly consisting of titanium oxynitride or titanium oxide + titanium nitride as a potential cause of the improved biological performance. Translated to the clinical field of intracranial aneurysm treatment, the improved biocompatibility has the potential to increase both safety (low thrombogenicity) and effectiveness (aneurysm neck reconstruction).

Targeting von Willebrand Factor in Ischaemic Stroke: Focus on Clinical Evidence

Despite great efforts in stroke research, disability and recurrence rates in ischaemic stroke remain unacceptably high. To address this issue, one potential target for novel therapeutics is the glycoprotein von Willebrand factor (vWF), which increases in thrombogenicity especially under high shear rates as it bridges between vascular sub-endothelial collagen and platelets. The rationale for vWF as a potential target in stroke comes from four bodies of evidence. (1) Animal models which recapitulate the pathogenesis of stroke and validate the concept of targeting vWF for stroke prevention and the use of the vWF cleavage enzyme ADAMTS13 in acute stroke treatment. (2) Extensive epidemiologic data establishing the prognostic role of vWF in the clinical setting showing that high vWF levels are associated with an increased risk of first stroke, stroke recurrence or stroke-associated mortality. As such, vWF levels may be a suitable marker for further risk stratification to potentially fine-tune current risk prediction models which are mainly based on clinical and imaging data. (3) Genetic studies showing an association between vWF levels and stroke risk on genomic levels. Finally, (4) studies of patients with primary disorders of excess or deficiency of function in the vWF axis (e.g. thrombotic thrombocytopenic purpura and von Willebrand disease, respectively) which demonstrate the crucial role of vWF in atherothrombosis. Therapeutic inhibition of VWF by novel agents appears particularly promising for secondary prevention of stroke recurrence in specific sub-groups of patients such as those suffering from large artery atherosclerosis, as designated according to the TOAST classification.

The Use of Embolic Protection Devices Is Associated With a Lower Stroke and Death Rate After Carotid Stenting

OBJECTIVES

The aim of this study was to analyze the association between intraprocedural and periprocedural variables and in-hospital stroke or death rate after carotid artery stenting.

BACKGROUND

In Germany, all open surgical and endovascular procedures on the extracranial carotid artery must be documented in a statutory nationwide quality assurance database.

METHODS

A total of 13,086 carotid artery stenting procedures for asymptomatic (63.9%) or symptomatic carotid stenosis (mean age 69.7 years, 69.7% men) between 2009 and 2014 were recorded. The following variables were analyzed: stent design, stent material, neurophysiological monitoring, periprocedural antiplatelet medication, and use of an embolic protection device. The primary outcome was in-hospital stroke or death. Major stroke or death, any stroke, and death, all until discharge, were secondary outcomes. Adjusted relative risks (RRs) were assessed using multilevel multivariable regression analyses.

RESULTS

The primary outcome occurred in 2.4% of the population (1.7% in asymptomatic and 3.7% in symptomatic patients). The multivariable analysis showed an independent association between the use of an embolic protection device and lower in-hospital rates of stroke or death (adjusted RR: 0.65; 95% confidence interval [CI]: 0.50 to 0.85), major stroke or death (adjusted RR: 0.60; 95% CI: 0.43 to 0.84), and stroke (adjusted RR: 0.57; 95% CI: 0.43 to 0.77). Regarding the occurrence of in-hospital death, there was no significant association (adjusted RR: 0.78; 95% CI: 0.46 to 1.35). None of the outcomes was associated with stent design, stent material, neurophysiological monitoring, or antiplatelet medication.

CONCLUSIONS

The use of an embolic protection device was independently associated with lower in-hospital risk for stroke or death, major stroke or death, and stroke.

Carotid Stenting in Neuroradiology : A Short Journey from the Past to Current Debates

After a period of stagnation due to negative results of randomized trials for patients with symptomatic stenosis, the relevance of carotid artery stenting (CAS) is increasing again. CAS has become an important and evidence-based part of interventional stroke treatment. Our ability to manage acute recanalization of carotid occlusions and other niche indications properly led some skeptical neurologists to trust in carotid intervention for elective cases as well. The evolution of CAS from initial euphoria to more realistic views under consideration of trial results and guidelines is reviewed. Quality assurance in Germany proves that CAS complication rates within the carotid endarterectomy (CEA) quality criteria are feasible even with higher proportions of high-risk patients. Recent trial results showed that long-term efficacy of CAS or CEA are not significantly different. Other than in symptomatic stenoses, acute complication rates of both means treatment does not differ in asymptomatic patients, where medical therapy becomes increasingly competitive. Technical issues of CAS like the cell design of stents or the usefulness of embolic protection are still under discussion. We will see whether CAS results will further improve over time. Standardized techniques, proper training, and patient selection are important for acute and elective cases.

History and Current Status of Endovascular Management for the Extracranial Carotid and Supra-Aortic Vessels

Few procedures in the history of medicine have been more controversial than carotid artery stenting (CAS) for the management of carotid artery occlusive disease. Introduced just as the randomized trials were establishing carotid endarterectomy as the gold standard for carotid interventions, CAS has finally reached the point in its development when dedicated stenting systems are being tested in randomized clinical trials. Assisted by the concomitant use of distal protection devices, CAS has shown equipoise with endarterectomy in terms of safety at 30 days. This review summarizes the completed and ongoing CAS trials and the applications of endovascular techniques in the supra-aortic vessels.

Endovascular Intervention for Stenosis Following Carotid Stent-Supported Angioplasty

This report is on a patient with symptomatic late restenosis after carotid stent-supported angioplasty (CSSA). Initially, the patient underwent carotid endarterectomy (CEA) with primary closure in response to an index transient ischemic attack 13 months before CSSA. He returned with angiographic evidence of recurrent carotid artery stenosis. A balloon-expandable stent was deployed with technical success. Follow-up angiography 1 year later showed an asymptomatic, noncritical in-stent restenosis (50%). Three years after the initial stent placement, the patient presented with ischemic symptoms and a carotid duplex confirming critical restenosis. The patient was successfully treated by deployment of a stent within a stent and showed significant hemodynamic improvement. This is a case report of late progressive restenosis, which raises concerns about long-term patency of CSSA in patients with aggressive postendarterectomy recurrence.

Carotid Artery Stenting: Current Status and Future Directions

Carotid endarterectomy has been the mainstay of therapy for carotid occlusive disease in stroke prevention. Recent advances in endovascular technology has made carotid angioplasty and stenting a therapeutic modality in the treatment of carotid occlusive disease. The enthusiasm for this minimally invasive carotid intervention is hampered by the possibility of stentrelated cerebral embolization, which can result in neurologic complications. Although current available data indicate that the results regarding success and complication rates are similar between carotid stenting and endarterectomy, numerous prospective clinical trials are currently underway to evaluate the efficacy of carotid artery stenting using various forms of cerebral protection devices. This article reviews the current status of carotid stenting, including recent clinical studies and ongoing prospective trials. Strategies relating to cerebral embolization protection are also discussed.

Angioplasty and Stenting of the Extracranial Carotid Arteries

Purpose:

To study the feasibility and safety of stent-supported angioplasty in the treatment of atherosclerotic stenoses of the extracranial carotid arteries.

Methods:

Carotid angioplasty was attempted in 174 arteries (163 patients: 126 males; mean age: 71 ± 10 years, range 47 to 93). Mean lesion length was 15.1 ± 4.1 mm, and mean percent stenosis was 83.8% ± 7.3% (reference diameter 5.8 ± 0.7 mm). The majority (106, 65%) were asymptomatic (51% of all patients had severe coronary disease, 32% had peripheral vascular diseases). Patients underwent independent neurological examination, computed tomography, duplex ultrasonography, and angiography preprocedurally, 24 hours after the procedure, and at 6-month follow-up intervals. Most (142, 82%) carotid arteries were treated without cerebral protection, but a protective triple coaxial catheter was used in 32 (18%) patients. Stents (primarily Palmaz and Wallstent) were deployed routinely in all cases; 18% were implanted without predilation.

Results:

Immediate technical success was 173 of 174 (99.4%) (1 access failure referred electively to surgery). Eight (4.6%) neurological complications occurred in the periprocedural period: 3 transient ischemic attacks, 2 minor strokes, and 3 major strokes (1 amaurosis and 2 hemiplegias). Two major complications developed despite cerebral protection. There were no deaths or myocardial infarctions and only 3 cervical access site hematomas. Over a mean 12.7 ± 9.2 month follow-up (range 1 to 36), no ipsilateral neurological complications have been seen. There were 4 (2.3%) restenoses (3 redilated, 1 treated medically) and 1 mild Palmaz stent compression, all found within the first 6 months. Primary and secondary patencies at 3 years are 96% and 99%, respectively.

Conclusions:

Angioplasty with routine stenting seems feasible and safe for treating certain types of carotid stenoses even in high-surgical risk patients; however, randomized trials are necessary before this treatment can be offered as an alternative to endarterectomy.

Carotid Stenting with Cerebral Protection: First Clinical Experience Using the PercuSurge GuardWire System

Purpose:

To study the feasibility and safety of carotid angioplasty and stenting using a new cerebral protection device that temporarily occludes the distal internal carotid artery (ICA).

Methods:

Forty-eight high-risk patients (39 men, mean age 69.1 ± 8 years, range 54 to 86) with 53 ICA stenoses underwent percutaneous angioplasty and stenting via the femoral approach under cerebral protection afforded by a 0.014-inch GuardWire balloon occlusion device. Mean stenosis was 82.1% ± 9.65% (range 70 to 96) and mean lesion length was 16.0 ± 7.5 mm (range 6 to 50). Thirty-three (62%) lesions were calcified, and 38 (72%) were ulcerated. Thirty-two (60%) of the lesions were asymptomatic. With the occlusion balloon inflated in the distal ICA, the lesion was dilated and stented. The area was cleaned by aspiration and flushed via an aspiration catheter advanced over the wire. Blood samples were collected from the external carotid artery (ECA) and analyzed to measure the size and number of particles collected. Computed tomography and neurological examinations were performed the day after the procedure.

Results:

Immediate technical success was achieved in all patients with the implantation of 38 Palmaz stents, 8 Expander stents, and 11 Wallstents. Carotid occlusion was well tolerated in all patients but 1 who had multiple, severe carotid lesions and poor collateralization. Mean cerebral flow occlusion time was 346 ± 153 seconds during predilation and 303 ± 143 seconds during stent placement. Total mean flow occlusion time was 542 ± 243 seconds. One immediate neurological complication (transient amaurosis) occurred in a patient who had an anastomosis between the external carotid (EC) and ICA territories. Debris was removed in all patients with a mean 0.8-mm diameter catheter.

Conclusion:

Cerebral protection with the GuardWire device is easy, safe, and effective in protecting the brain from cerebral embolism. Larger studies are warranted.

Endovascular Stents for Carotid Artery Occlusive Disease

Purpose:

To study the feasibility and safety of endovascular stenting of cervical carotid artery stenosis.

Methods:

Between April 1994 and May 1997, 108 consecutive patients (58 men; mean age 70.1 years) with ≥ 70% carotid stenosis were treated with percutaneous stent implantation under a protocol that featured independent neurological review. Forty-four percent were asymptomatic. Over half the lesions (59%) were in the internal carotid artery; the mean stenosis was 86%. Palmaz stents were implanted without cerebral protection following preliminary balloon dilation; two Wallstents were used in long lesions.

Results:

Carotid stents were successfully placed in 108 of 114 (95%) lesions. Of the 6 technical failures, 5 were access related and 1 was due to seizures during balloon dilation. Two major (1.8%) and 2 minor (1.8%) strokes occurred (3.7% stroke rate for 108 patients; 3.5% in 114 procedures), all in symptomatic patients, one of whom died. There were 5 (4.4%) transient ischemic attacks and 2 (1.8%) brief seizure episodes during dilation. One patient died of a cardiac event on day 20. The all stroke or death rate was 5.3% based on 114 arteries at risk (5.6% in 108 patients). In the mean 6-month follow-up (range 1 to 36) of 97 eligible patients, 3 (3.1%) died from unrelated causes. There was 1 restenosis (1.0%) from a stent compression, which was successfully redilated. There were no neurological sequelae, cranial palsies, or cases of stent or vessel thrombosis in follow-up.

Conclusions:

The use of stents in the treatment of cervical carotid occlusive disease appears feasible, effective in the short term, and without excessive risk of periprocedural stroke.

Influence of Age upon Complications of Carotid Artery Stenting

Purpose:

To examine the impact of age upon the development of neurological and major systemic complications during or after carotid artery stenting.

Methods:

We reviewed the complications that occurred in patients undergoing elective carotid stent implantation between September 1994 and August 1996. The study population was then divided into 3 groups according to age: ≥ 80 (group A), 75 to 79 (group B), and ≤ 74 (group C) years. The rates of death, major and minor stroke, and myocardial infarction were compared among the groups, as well as with the rates reported by the major carotid endarterectomy (CEA) trials.

Results:

During the study period, 182 patients (216 vessels) were treated with carotid stenting. There were 19 (10.4%) complications: 1 (0.5%) death, 2 (1.1%) major strokes, 15 (8.2%) minor strokes, and 1 (0.5%) myocardial infarction. Neurological complications were clearly related to increased age with rates of 25.0% in group A versus 8.6% in group C (p = 0.042). The overall per patient rate of death or major stroke was 1.6% (1.4% per vessel).

Conclusions:

Increasing age has a negative impact on the rate of complications in carotid stent patients. However, the majority of those complications are minor. The relative roles of medical therapy, stenting, and CEA in patients > 80 years of age must await the results of randomized trials.

Traumatic Carotid Artery Dissection and Pseudoaneurysm Treated with Endovascular Coils and Stent

Purpose:

To report a case of post-traumatic internal carotid artery dissection and pseudoaneurysm formation at the C-1 level successfully treated by a percutaneous endovascular technique.

Methods and Results:

A 20-year-old female presented 72 hours after a motor vehicle accident with incomplete occulosympathetic paresis (Horner's syndrome), carotidynia, and left-sided weakness. Arteriography confirmed the diagnosis of carotid dissection and an associated 1.5-cm × 2.5-cm pseudoaneurysm at the C-1 level. Neuroradiologists embolized the pseudoaneurysm with Guglielmi detachable coils and controlled the dissection with placement of a Wallstent.

Conclusions:

This report illustrates successful percutaneous endovascular treatment of a carotid dissection and pseudoaneurysm near the base of the skull.

Determinants of In-Stent Restenosis after Carotid Angioplasty: A Case-Control Study

Purpose:

To report a retrospective study that sought to identify clinical factors contributing to the development of in-stent restenosis in the carotid arteries, to profile the patients at greatest risk, and to review the treatment modalities evolved from our experience.

Methods:

Between December 2000 and April 2003, 195 carotid angioplasty/stenting (CAS) procedures (12 bilateral) were performed in 183 patients (131 men; median age 65.9 years, interquartile range 55.2–72.7). Stenting for de novo stenoses was performed in 119 (61%) carotid arteries; 76 (39%) vessels were treated for postsurgical restenosis. Nearly two thirds of the patients (117, 64%) were symptomatic. Patients were evaluated at 3 and 6 months and at 6-month intervals thereafter with duplex ultrasonography. Angiography was used to confirm any recurrent lesion detected on the ultrasound scan.

Results:

Overall perioperative neurological complications included 4 (2.2%) minor strokes, 1 (0.5%) intracranial hemorrhage, and 1 (0.5%) major stroke; both patients with major neurological complications died at 5 and 12 days, respectively, after the procedure. During the 12.5-month follow-up (range 0–27.2), 3 non-procedure-related late deaths and another 9 (4.9%) neurological events occurred (2 strokes and 7 transient ischemic attacks). In-stent restenosis after CAS was present in 10 (5.2%) of 193 carotid arteries (9/181 patients) in follow-up; all but 1 artery had been treated for postsurgical restenosis. All lesions were treated secondarily with endovascular procedures. Statistical analysis demonstrated that postsurgical restenosis was the only predictive factor for the development of in-stent restenosis (OR 15.5, 95% CI 2.05 to 125.6, p = 0.001) in this cohort.

Conclusions:

The present study, far from being exhaustive on the subject, indicates that patients who develop restenosis after carotid endarterectomy are also prone to develop restenosis after CAS; moreover, although strongly recommended for postsurgical restenosis, CAS carries a greater risk of in-stent restenosis in this subgroup, thus reducing the benefits of this procedure.

Is Extended Duration of Dual Antiplatelet Therapy After Carotid Stenting Beneficial?

The optimal antithrombotic regimen after carotid artery stenting (CAS) remains uncertain. We aimed to elucidate if long-term duration of aspirin plus clopidogrel after CAS would provide clinically relevant benefit. Patients receiving CAS were identified from the National Health Insurance Research Database, Taiwan. The discharge date following CAS was defined as index date. The study participants were divided into groups according to the prescribed duration of antiplatelet after the index date. They included the insufficient (< 30 days), moderate (30-41 days), and considerable (≥ 42 days) groups. The risk of ischemic stroke, composite vascular outcome, and death were interested outcomes. To eliminate event-related prescription change, all outcomes that occurred within 42 days were excluded. Follow-up started 42 days after the index date and was censored when an event occurred or at 6 months. A total of 4903 patients received CAS from 2004 to 2011. The total participants recruited for analysis (n = 2829) included the insufficient (n = 688), moderate (n = 372), and considerable groups (n = 1769). The event rates of ischemic stroke (3.92, 2.69, and 2.77%, P = 0.30), composite vascular stroke (5.52, 4.03, and 4.41%, P = 0.42), and death (3.05, 2.42, and 2.32%, P = 0.58) were similar for each group. Cox regression did not demonstrate significant associations between antiplatelet duration and the outcomes of interest. Long-term use of aspirin plus clopidorel after CAS did not decrease the risk of ischemic stroke, composite vascular events, or death during 6 months of follow-up. More research on the appropriate duration of post-CAS dual antiplatelet is essential.

Intravascular Near-Infrared Spectroscopy: A Possible Tool for Optimizing the Management of Carotid Artery Disease

Stroke is the second most common cause of morbidity and mortality in the Western nations. It is estimated that approximately one-fifth of all strokes or transient ischemic attacks are caused by carotid artery disease. Thus, treatment of carotid artery disease as a mean of stroke prevention is extremely important. Since the introduction of carotid endarterectomy, debate has persisted over the treatment strategy for carotid artery disease. Current recommendations have many potential flaws because they are often based on older trials performed before the introduction of modern pharmacotherapy and are mostly based on the angiographic degree of stenosis, without an emphasis on the pathophysiology of the disease. Most carotid events are caused by rupture or distal embolization of the content of an unstable atherosclerotic plaque with a large lipid pool. Thus, it is plausible that the information regarding the composition of the atherosclerotic plaque could play an important role in deciding on a treatment strategy. In this review article, we provide information about near-infrared spectroscopy, a new invasive imaging modality, which seems to be capable of providing such information.

Carotid artery stenting

Carotid artery stenting (CAS) has achieved clinical equipoise with carotid endarterectomy (CEA), as evidenced by 2 large U.S. randomized clinical trials, multiple pivotal registry trials, and 2 multispecialty guideline documents endorsed by 14 professional societies. The largest randomized trial conducted in patients at average surgical risk of CEA, CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) found no difference between CAS and CEA for the combined endpoint of stroke, death, and myocardial infarction (MI) after 4 years of follow-up. The largest randomized trial comparing CAS and CEA in patients at increased surgical risk, SAPPHIRE (Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy), looked at 1-year stroke, death, and MI incidence and found no difference in symptomatic patients, but a significantly better outcome in asymptomatic patients for CAS (9.9% vs. 21.5%; p = 0.02). Given that >70% of carotid revascularization procedures are performed in asymptomatic patients for primary prevention of stroke, it is incumbent upon clinicians to demonstrate that revascularization has an incremental benefit over highly effective modern medical therapy alone.

Complications and Solutions with Carotid Stenting

Complications of carotid stenting can be classified as neurologic, cardiovascular, death, carotid, access site, device malfunctions, and general and late complications. The risk of most complications is related to readily identifiable patient and anatomic factors. Management and outcome of complications require immediate recognition and a team-based approach to patient care.

Carotid artery stenting - current status of the procedure

Surgical carotid endarterectomy (CEA) was long considered the standard approach for the treatment of atherosclerotic carotid artery disease. This was based on results of several randomized trials demonstrating its effectiveness over the best medical therapy. In the past two decades, patients identified high-risk for surgery were offered carotid artery stenting (CAS) as a less invasive option. Despite its initial limitations, CAS has evolved into an elaborate method currently considered to be equivalent and in selected patients even preferable to CEA. However, outcomes of both procedures are highly operator dependent and a simple stratifying method to prioritize CAS, CEA or medical therapy only has not yet been proposed. In addition, recently published randomized trials highlighted the importance of proper patient selection and rigorous training contributing to low absolute rates of (procedural) adverse events. This review discusses the history and evidence for carotid revascularization and briefly presents technical aspects and innovations in CAS.

[Carotid artery stenting technique]

Over the past 25 years carotid artery stenting (CAS) has emerged as an alternative to carotid endarterectomy (CEA). Most of all younger patients and symptomatic patients with contralateral carotid artery occlusion particularly benefit from CAS. To achieve an optimal result with CAS, patient selection and even more important, knowledge and experience of the interventionist is crucial. The periprocedural complication rate of CAS in large experienced centers is lower (2-3%) than those in randomized trials. Several different devices are now available which allow the procedure to be tailored according to patient anatomy and lesion complexity. Complications like hyperperfusion syndrome and intracerebral bleeding, rupture of side branches of the external or internal carotid artery as well as problems caused by slow flow can be widely avoided by adequate experience.

Carotid artery stenting: patient, lesion, and procedural characteristics that increase procedural complications

From the earliest experiences with carotid artery stenting (CAS) presumptive high risk features have included thrombus-containing lesions, heavily calcified lesions, very tortuous vessels, and near occlusions. In addition patients have been routinely excluded from CAS trials if they have contra-indications to dual antiplatelet therapy (aspirin and thienopyridines), a history of bleeding complications and severe peripheral arterial disease (PAD) making femoral artery vascular access difficult. Variables that increase the risk of CAS complications can be attributed to patient characteristics, anatomic or lesion features, and procedural factors. Clinical features such as older age (≥80 years), decreased cerebral reserve (dementia, multiple prior strokes, or intracranial microangiopathy) and angiographic characteristics such as excessive tortuosity (more than two 90° bends within 5 cm of the target lesion) and heavy calcification (concentric calcification ≥ 3 mm in width) have been associated with increased CAS complications. Other high risk CAS features include those that prolong catheter or guide wire manipulation in the aortic arch, make crossing a carotid stenosis more difficult, decrease the likelihood of successful deployment or retrieval of an embolic protection device (EPD), or make stent delivery or placement more difficult. Procedure volume for the operator and the catheterization laboratory team are critical elements in reducing the risk of the procedure. In this article, we help CAS operators better understand procedure risk to allow more intelligent case selection, further improving the outcomes of this emerging procedure.

Carotid artery disease and interventional therapy

PURPOSE OF REVIEW

Major results of recent clinical trials for carotid artery disease are changing the understanding of management.

RECENT FINDINGS

A major trial comparing carotid endarterectomy with carotid angioplasty and stenting for symptomatic or asymptomatic patients suggests comparable results by overall outcomes analyses, and different results by subset analyses. These results modify the findings of prior trials.

SUMMARY

Based on age there appear to be differences in outcomes that may influence decision for management for such patients.

Endovascular treatment of penetrating traumatic injuries of the extracranial carotid artery

PURPOSE

To describe the clinical and angiographic results of endovascular therapy for traumatic injuries of the extracranial carotid artery.

MATERIALS AND METHODS

The clinical and angiographic features of 36 traumatic injuries of the carotid artery during a 12-year period were reviewed. There were 35 male patients (97.2%) and 1 female patient (2.8%) with an average age of 28.8 years (range 13-60 years). Of the 36 lesions of the carotid artery, 29 (80.6%) were the result of gunshot injury, and 7 (19.4%) were secondary to stab wounds. In 24 (66.7%) instances, the injury resulted in a pseudoaneurysm; in 7 (19.4%), in an arteriovenous fistula (AVF); in 4 (11.1%), in a dissection; and in 1 (2.8%), in inactive bleeding. All patients were treated with an endovascular approach using different techniques (balloon occlusion, embolization, or stent deployment).

RESULTS

Endovascular therapy resulted in documented lesion occlusion in 34 (94.4%) patients. Two patients declined any follow-up postprocedural imaging; however, they have remained asymptomatic. Clinical improvement was documented in 35 (97.2%) patients, and there was one procedure-related complication with fatal consequences.

CONCLUSIONS

In this series, endovascular techniques were an effective method of treatment. It was possible to use different endovascular reconstructive techniques or parent artery occlusion depending on the degree of vessel damage, with resolution of clinical symptoms and avoidance of surgery in most cases.

Recurrent subacute in-stent restenosis after carotid artery stenting due to plaque protrusion

A 70-year-old male presented with transient ischemic attacks manifesting as right hemiparesis and motor aphasia due to severe left cervical internal carotid artery stenosis. Carotid artery stenting (CAS) using a flow-reversal system was performed without complications. However, the patient exhibited transient right hemiparesis and motor aphasia 10 days after CAS. Emergent angiography demonstrated in-stent restenosis. In-stent percutaneous transluminal angioplasty and CAS were performed successfully using a distal protection system. However, duplex ultrasound scanning revealed progressive in-stent restenosis, 3 and 6 days after the re-treatment. Emergent angiography again demonstrated in-stent restenosis. Urgent stent removal and carotid endarterectomy were performed. Plaque had prolapsed through the stent. Histological examination revealed that the specimen was mainly plaque consisting of cholesterol crystals and macrophages. The patient was able to return to independent life without neurological deficit. Repeated endovascular surgery with appropriate antiplatelet and anticoagulation therapy should be attempted initially to treat in-stent restenosis. Endarterectomy with stent removal should be considered as a rescue option, especially if plaque protrusion is identified.

How to avoid complications associated with carotid angioplasty and stenting

Carotid angioplasty and stenting (CAS) has been proposed as an alternative to surgery and is now performed more frequently and is well accepted, at least for high surgical risk patients. However, complications and particularly embolic strokes, even with a meticulous technique, can occur at any step of the procedure. Silent embolism is detected after CAS and may be a problem that needs to be discussed. To avoid and reduce these complications associated with CAS, it is important to have good indications dependent upon on good patient and lesions selection, as well as correct technique. New parameters have been proposed, particularly for asymptomatic lesions. The authors consider that embolic protection devices (EPDs) are mandatory for CAS, and new techniques will be presented. The choice of the EPD depends on the clinical status of the patient, the lesion morphology and characteristics, and the anatomy of the artery. All stents are not equivalent and so a good choice of the stent is necessary to avoid and reduce the complications associated with CAS, and experienced operators are also needed. With all these considerations, CAS can now be performed with acceptable outcomes and in certain population the results are comparable or superior to surgery. The results of ongoing randomized trials are awaited.