Safety of endovascular treatment of carotid artery stenosis compared with surgical treatment: A meta-analysis

Methodological quality and redundancy of systematic reviews that compare endarterectomy versus stenting for carotid stenosis

A review of systematic reviews (SRs) and a critical appraisal study was conducted at Escola Paulista de Medicina, Universidade Federal de São Paulo (Unifesp). The objectives of this review are (1) to identify all published SRs comparing the effectiveness and safety of carotid endarterectomy (CEA) versus carotid artery stenting (CAS) for carotid artery stenosis, (2) to assess their methodological quality and (3) to compare the primary studies contained in each SR. We included 17 SRs published between 2005 and 2017. None of the SRs fulfilled all items of AMSTAR-2. The overall confidence in the results was graded as critically low for 16 SRs (94%) and low for 1 SR (6%). Five items were judged inadequate in all SRs: reference to a published protocol, explanation to the selection of study design, comprehensive search of the literature, methods for statistical combination of findings and consideration of the risk of bias on the results of meta-analysis. In total, 15 randomised clinical trials (RCTs) were included at least in one SR. The number of included RCTs in each SR was inconsistent (4 to 15) and was not related to the year of publication of the SR. Our study found redundant and low methodological quality SR comparing CAS versus CEA for carotid stenosis.

[Epidemiology of cerebral perioperative vascular accidents]

OBJECTIVES

Stroke is a well-described postoperative complication, after carotid and cardiac surgery. On the contrary, few studies are available concerning postoperative stroke in general non-cardiac non-carotid surgery. The high morbid-mortality of stroke justifies an extended analysis of recent literature.

ARTICLE TYPE

Systematic review.

DATA SOURCES

Firstly, Medline and Ovid databases using combination of stroke, cardiac surgery, carotid surgery, general non-cardiac non-carotid surgery as keywords; secondly, national and European epidemiologic databases; thirdly, expert and French health agency recommendations; lastly, reference book chapters.

RESULTS

In cardiac surgery, with an incidence varying from 1.2 to 10% according to procedure complexity, stroke occurs peroperatively in 50% of cases and during the first 48 postoperative hours for the others. The incidence of stroke after carotid surgery is 1 to 20% according to the technique used as well as operator skills. Postoperative stroke is a rare (0.15% as mean, extremes around 0.02 to 1%) complication in general surgery, it occurs generally after the 24-48th postoperative hours, exceptional peroperatively, and 40% of them occurring in the first postoperative week. It concerned mainly aged patient in high-risk surgeries (hip fracture, vascular surgery). Postoperative stroke was associated to an increase in perioperative mortality in comparison to non-postoperative stroke operated patients.

CONCLUSION

Postoperative stroke is a quality marker of the surgical teams' skill and has specific onset time and induces an increase of postoperative mortality.

Carotid Endarterectomy Versus Stenting: A Meta-Analysis of Randomized Trials

Background:

A meta-analysis of randomized controlled trials (RCTs) was conducted to update the available evidence on the safety and efficacy of carotid endarterectomy (CEA) versus carotid artery stenting (CAS) in the treatment of carotid artery stenosis.

Methods:

A comprehensive search was performed of MEDLINE, EMBASE, CENTRAL, bibliographies of included articles and past systematic reviews, and abstract lists of recent scientific conferences. For each reported outcome, a Mantel-Haenszel random-effects model was used to calculate odds ratios (ORs) and 95% confidence intervals (CI). The I2 statistic was used as a measure of heterogeneity.

Results:

Twelve RCTs enrolling 6,973 patients were included in the meta-analysis. Carotid artery stenting was associated with a significantly greater odds of periprocedural stroke (OR 1.72, 95% CI 1.20 to 2.47) and a significantly lower odds of periprocedural myocardial infarction (OR 0.47, 95% CI 0.29 to 0.78) and cranial neuropathy (OR 0.08, 95% CI, 0.04 to 0.16). The odds of periprocedural death (OR 1.11, 95% CI 0.56 to 2.18), target vessel restenosis (OR 1.95, 95% CI 0.63 to 6.06), and access-related hematoma were similar following either intervention (OR 0.60, 95% CI 0.30 to 1.21).

Conclusions:

In comparison with CEA, CAS is associated with a greater odds of stroke and a lower odds of myocardial infarction. While the results our meta-analysis support the continued use of CEA as the standard of care in the treatment of carotid artery stenosis, CAS is a viable alternative in patients at elevated risk of cardiac complications.

Balloons in endovascular neurosurgery: history and current applications

The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

Cohort profile: Greifswald approach to individualized medicine (GANI_MED)

BACKGROUND

Individualized Medicine aims at providing optimal treatment for an individual patient at a given time based on his specific genetic and molecular characteristics. This requires excellent clinical stratification of patients as well as the availability of genomic data and biomarkers as prerequisites for the development of novel diagnostic tools and therapeutic strategies. The University Medicine Greifswald, Germany, has launched the "Greifswald Approach to Individualized Medicine" (GANI_MED) project to address major challenges of Individualized Medicine. Herein, we describe the implementation of the scientific and clinical infrastructure that allows future translation of findings relevant to Individualized Medicine into clinical practice.

METHODS/DESIGN

Clinical patient cohorts (N > 5,000) with an emphasis on metabolic and cardiovascular diseases are being established following a standardized protocol for the assessment of medical history, laboratory biomarkers, and the collection of various biosamples for bio-banking purposes. A multi-omics based biomarker assessment including genome-wide genotyping, transcriptome, metabolome, and proteome analyses complements the multi-level approach of GANI_MED. Comparisons with the general background population as characterized by our Study of Health in Pomerania (SHIP) are performed. A central data management structure has been implemented to capture and integrate all relevant clinical data for research purposes. Ethical research projects on informed consent procedures, reporting of incidental findings, and economic evaluations were launched in parallel.

Recommendations for management of patients with carotid stenosis

Stroke is a one of the leading causes of morbidity and mortality in the world. Carotid atherosclerosis is recognized as an important factor in stroke pathophysiology and represents a key target in stroke prevention; multiple treatment modalities have been developed to battle this disease. Multiple randomized trials have shown the efficacy of carotid endarterectomy in secondary stroke prevention. Carotid stenting, a newer treatment option, presents a less invasive alternative to the surgical intervention on carotid arteries. Advances in medical therapy have also enabled further risk reduction in the overall incidence of stroke. Despite numerous trials and decades of clinical research, the optimal management of symptomatic and asymptomatic carotid disease remains controversial. We will attempt to highlight some of the pivotal trials already completed, discuss the current controversies and complexities in the treatment decision-making, and postulate on what likely lies ahead. This paper will highlight the complexities of decision-making optimal treatment recommendations for patients with symptomatic and asymptomatic carotid stenosis.

Carotid endarterectomy is superior to carotid angioplasty and stenting for perioperative and long-term results

OBJECTIVE

Carotid angioplasty and stenting (CAS) has challenged carotid endarterectomy (CEA) as the therapy of choice for carotid disease. This meta-analysis aims at summarizing the most current body of evidence.

METHODS

All prospective, controlled clinical trials comparing CEA versus CAS were included. The outcome measures of interest were relative risk (RR) of 30-day stroke, 30-day stroke/death, long-term risk of stroke, and risk of restenosis.

RESULTS

The RR of 30-day stroke for CAS was 1.6 times that of CEA (RR 1.6; 95%CI 1.2-2.0, P = .001). The 30-day RR of stroke/death was 1.5 times higher for CAS (RR 1.5; 95%CI 1.1-2.1, P = .008). There was a higher risk of long-term stroke (RR 1.2; 95%CI 1.0-1.5, P = .043). The risk of restenosis was twice for CAS (RR 1.8; 95%CI 1.1-3.1, P = .04).

CONCLUSION

The 30-day RR of stroke, stroke/death, long-term risk of stroke, and risk of restenosis are consistently higher for carotid artery stenting (CAS).

Anatomical and technical factors associated with stroke or death during carotid angioplasty and stenting: results from the endarterectomy versus angioplasty in patients with symptomatic severe carotid stenosis (EVA-3S) trial and systematic review

BACKGROUND AND PURPOSE

The purposes of this study were to assess the relationships between anatomic and technical factors and the 30-day risk of stroke or death after carotid angioplasty and stenting in the Endarterectomy versus Stenting in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial and to perform a systematic review of the literature.

METHODS

We included patients from EVA-3S in whom carotid stenting was attempted irrespective of allocated treatment. Two radiologists blinded to clinical data independently assessed the aortic arch and carotid arteries on procedural angiograms. In addition, we performed a systematic review of studies that reported 30-day risk of stroke or death in relation with arterial anatomy and technique. Outcomes were stroke or death and stroke occurring within 30 days of the carotid angioplasty and stenting procedure.

RESULTS

Two hundred sixty-two patients from EVA-3S fulfilled the inclusion criteria (including 1 initially allocated to surgery and 13 in whom stent insertion failed).Within 30 days after the procedure, 25 (9.5%) patients had a stroke or had died. The risk of stroke or death was higher in patients with internal carotid artery-common carotid artery angulation ≥60° (relative risk, 4.96; 2.29 to 10.74) and lower in those treated with cerebral protection devices (relative risk [RR], 0.38; 0.17 to 0.85). In the systematic review (56 studies; 34 398 patients), the risk of stroke or death was higher in patients with left-sided carotid angioplasty and stenting (RR, 1.29; 1.05 to 1.58), increased internal carotid artery-common carotid artery angulation (RR, 3.41; 1.52 to 7.63), and when the target internal carotid artery stenosis was >10 mm (RR, 2.36; 1.28 to 3.38). There was no significant increase in risk of stroke or death in patients with Type III aortic arch, aortic arch calcification, or with ostial involvement, calcification, ulceration or degree of stenosis of the target internal carotid artery stenosis. The use of a cerebral protection device was associated with a lower risk of stroke or death (RR, 0.55; 0.41 to 0.73). Risk was not related with stent or cerebral protection device type.

CONCLUSIONS

Our results strongly suggest that some technical and anatomic factors, especially extreme angulation of the carotid artery, have an impact on the risks of carotid angioplasty and stenting.

Intensive medical therapy for asymptomatic carotid artery stenosis

The majority of carotid revascularization procedures are done in patients without recent symptoms of cerebral ischemia (asymptomatic carotid stenosis). In previous studies from the past two decades, the stroke risk associated with asymptomatic carotid stenosis has been estimated to be 2-2.5% per year. Given the relatively benign nature of asymptomatic carotid stenosis, it has been proposed that confining revascularization to a limited, higher-risk subgroup is a sensible strategy. Evidence is accumulating that improved medical therapy has led to a lower risk of stroke in medically treated patients and that ultrasound methods can identify higher-risk patients. These developments are highlighted in this article.

Secondary prevention of stroke

Stroke and transient ischemic attacks result from a range of mechanisms. Secondary prevention includes both conventional approaches to vascular risk-factor management (blood pressure lowering, cholesterol reduction with statins, smoking cessation and antiplatelet therapy) and more specific interventions, such as carotid endarterectomy or anticoagulation for atrial fibrillation. The relative importance of even conventional risk factors in stroke differs from coronary artery disease. Large clinical trials produce information on most aspects of stroke prevention. Stroke and transient ischemic attacks are now recognized as medical emergencies, with a high early risk of recurrence, and evidence is accumulating to support the importance of immediate institution of secondary preventative treatments. We review current literature on the secondary prevention of stroke.

Carotid revascularization using endarterectomy or stenting systems (CaRESS): 4-year outcomes

PURPOSE

To examine the 4-year outcomes from Carotid Revascularization using Endarterectomy or Stenting Systems (CaRESS) in light of the current reimbursement guidelines for carotid artery stenting (CAS) from the Centers for Medicare and Medicaid Services (CMS).

METHODS

CaRESS was designed as a prospective, nonrandomized comparative cohort study of a broad-risk population of symptomatic and asymptomatic patients with carotid stenosis. In all, 397 patients (247 men; mean age 71 years, range 43-89) were enrolled and underwent carotid endarterectomy (CEA; n = 254) or protected CAS (n = 143). More than 90% of patients had >75% stenosis; two thirds were asymptomatic. The primary endpoints included (1) all-cause mortality, (2) any stroke, and (3) myocardial infarction (MI), as well as the composite endpoints of (4) death and any nonfatal stroke and (5) death, nonfatal stroke, and MI. The secondary endpoints were restenosis, repeat angiography, and carotid revascularization. All patients were classified with respect to surgical risk, symptom status, and stenosis grade based on criteria published by the CMS. In addition, separate analyses were performed comparing genders and octogenarians to those <80 years old.

RESULTS

No significant differences in the primary outcome measures were found between the CEA and CAS groups in the 4-year analysis. The incidences of any stroke at 4 years were 9.6% for CEA and 8.6% for CAS (p = 0.444); when combined with death, the composite death/nonfatal stroke rates were 26.5% for CEA versus 21.8% for CAS (p = 0.361). The composite endpoint of death, nonfatal stroke, and MI at 4 years was 27.0% in CEA versus 21.7% in CAS (p = 0.273) patients. The secondary endpoints of restenosis (p = 0.014) and repeat angiography (p = 0.052) were higher in the CAS arm. There were no differences in any of the subgroups stratified according the CMS guidelines or in the gender comparison. Four-year incidences of death/nonfatal stroke and death/nonfatal stroke/MI were higher in the CEA arm among patients <80 years of age (p = 0.049 and p = 0.030, respectively). There were no significant differences between these incidences in the octogenarian subgroup.

CONCLUSION

The risk of death or nonfatal stroke 4 years following CAS with distal protection is equivalent to CEA in a broad category of patients with carotid stenosis. There were no significant differences in stroke or mortality rates between high-risk and non-high-risk patients and no differences in outcomes between symptomatic and asymptomatic patients. After 4 years, CAS had a 2-fold higher restenosis rate compared to CEA. The risk of death/stroke or death/stroke/MI appears to be higher following CEA than CAS among patients <80 years of age, yet there is no statistically significant relationship between death, stroke, or MI among octogenarians.

Carotid Artery Stenting May Be Losing the Battle against Carotid Endarterectomy for the Management of Symptomatic Carotid Artery Stenosis, But the Jury Is Still Out

Carotid artery stenting (CAS) has emerged as a potential alternative to carotid endarterectomy (CEA) for the management of carotid artery stenosis. The purpose of this article is to provide an evaluation and critical overview of the trials comparing the early and later results of CAS with CEA for symptomatic carotid stenosis. The Cochrane Controlled Trials Register, PubMed/Medline, and EMBASE databases were searched up to February 1, 2009, to identify trials comparing the long-term outcomes of CAS with CEA. The MeSH terms used were “carotid artery stenting,” “carotid endarterectomy,” “symptomatic carotid artery stenosis,” “treatment,” “clinical trial,” “randomized,” and “long-term results,” in various combinations. One single-center and three multicenter randomized studies reporting their long-term results from the comparison of CAS with CEA for symptomatic carotid stenosis were identified. All four studies independently reached the conclusion that CAS may not provide results equivalent to those of CEA for the management of symptomatic carotid stenosis. A higher incidence of recurrent stenosis and peri- and postprocedural events accounted for the inferior results reported for CAS compared with CEA. Current data from randomized studies indicate that CAS provides inferior long-term results compared with CEA for the management of symptomatic carotid artery stenosis. However, it can be argued that all of these trials were performed when both CAS equipment and CAS operators had not evolved to their current status. Given that current equipment and mature experience are required for CAS before comparing it with the current “gold standard” procedure (CEA), the results of soon-to-be reported trials (Carotid Revascularization Endarterectomy vs Stenting Trial [CREST], International Carotid Stenting Study [ICSS], or others) may alter the current impression that CAS is inferior to CEA for the treatment of symptomatic carotid stenosis.

Mandatory diagnostic angiography for carotid artery stenosis prior to carotid artery intervention

INTRODUCTION

Revascularization is an important strategy for reducing stroke risk in patients with severe carotid atherosclerosis. Magnetic resonance angiography (MRA) and/or carotid ultrasound have traditionally been used as the only diagnostic modalities prior to revascularization. Patients undergoing CEA frequently have no further assessments of carotid anatomy prior to surgery. Evaluation with carotid ultrasound and MRA can often overestimate the degree of stenosis. We sought to determine if noninvasive imaging was sufficient for determining whether a patient should be referred for carotid intervention.

METHODS

We performed an analysis of 101 patients referred for carotid artery stenting (CAS). All patients had previously been evaluated with carotid ultrasound and 94% had undergone MRA as well. We sought to determine if noninvasive diagnostic imaging for carotid stenosis was sufficient to determine the necessity for endovascular intervention.

RESULTS

Of the 101 patients referred for carotid intervention, 36 (36%) were shown to have <70% stenoses and did not require intervention. Of those who had significant disease, 49 (75%) underwent successful CAS, 15 (23%) underwent CEA, and 1 patient was treated medically for a total occlusion. Three of the 36 patients not requiring carotid intervention were found to have subclavian stenosis. Two (4%) of the patients undergoing CAS and 4 (27%) of the patients undergoing CEA had minor complications. No patients suffered a major stroke, MI, or death at follow-up.

CONCLUSION

This analysis demonstrates that 36% of patients referred for endovascular intervention based on noninvasive imaging did not meet criteria by angiography. This emphasizes the need for carotid angiography prior to carotid intervention.

Endarterectomy Versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial: results up to 4 years from a randomised, multicentre trial

BACKGROUND

Carotid stenting is a potential alternative to carotid endarterectomy but whether this technique is as safe as surgery and whether the long-term protection against stroke is similar to that of surgery are unclear. We previously reported that in patients in the Endarterectomy Versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial, the rate of any stroke or death within 30 days after the procedure was higher with stenting than with endarterectomy. We now report the results up to 4 years.

METHODS

In this follow-up study of a multicentre, randomised, open, assessor-blinded, non-inferiority trial, we compared outcome after stenting with outcome after endarterectomy in 527 patients who had carotid stenosis of at least 60% that had recently become symptomatic. The primary endpoint of the EVA-3S trial was the rate of any periprocedural stroke or death (ie, within 30 days after the procedure). The prespecified main secondary endpoint was a composite of any periprocedural stroke or death and any non-procedural ipsilateral stroke during up to 4 years of follow-up. Other trial outcomes were any stroke or periprocedural death, any stroke or death, and the above endpoints restricted to disabling or fatal strokes. This trial is registered with ClinicalTrials.gov, number NCT00190398.

FINDINGS

262 patients were randomly assigned to endarterectomy and 265 to stenting. The cumulative probability of periprocedural stroke or death and non-procedural ipsilateral stroke after 4 years of follow-up was higher with stenting than with endarterectomy (11.1%vs 6.2%, hazard ratio [HR] 1.97, 95% CI 1.06-3.67; p=0.03). The HR for periprocedural disabling stroke or death and non-procedural fatal or disabling ipsilateral stroke was 2.00 (0.75-5.33; p=0.17). A hazard function analysis showed the 4-year differences in the cumulative probabilities of outcomes between stenting and endarterectomy were largely accounted for by the higher periprocedural (within 30 days of the procedure) risk of stenting compared with endarterectomy. After the periprocedural period, the risk of ipsilateral stroke was low and similar in both treatment groups. For any stroke or periprocedural death, the HR was 1.77 (1.03-3.02; p=0.04). For any stroke or death, the HR was 1.39 (0.96-2.00; p=0.08).

INTERPRETATION

The results of this study suggest that carotid stenting is as effective as carotid endarterectomy for middle-term prevention of ipsilateral stroke, but the safety of carotid stenting needs to be improved before it can be used as an alternative to carotid endarterectomy in patients with symptomatic carotid stenosis.