Interventional procedure overview of transfemoral carotid artery stent placement for asymptomatic extracranial carotid stenosis

Abreu P, Nogueira J, Rodrigues FB et al. (2017) Intracerebral hemorrhage as a manifestation of cerebral hyperperfusion syndrome after carotid revascularization: systematic review and meta-analysis. Acta neurochirurgica 159: 2089-2097

Systematic review and meta-analysis

n=28,956 (41 studies)

When comparing CAS with CEA, postprocedural intracerebral haemorrhage in the context of cerebral hyperperfusion syndrome was less frequent in CEA. It occurred less often in large series and was rare in asymptomatic patients. The most common risk factors were periprocedural hypertension and ipsilateral severe stenosis.

Review focuses on intracerebral haemorrhage.

Achim A, Lacko D, Huttl A et al. (2022) Impact of diabetes mellitus on early clinical outcome and stent restenosis after carotid artery stenting. Journal of Diabetes Research 4196195

Cohort study

n=1,940

Follow up: 12 months

There was no significant difference between the 2 groups in terms of early and late MACCEs (composite of transient ischemic attack, major stroke, myocardial infarction, and death), with an early rate of 4% nondiabetics versus 5%, p=0.08 and 2% nondiabetics versus 2% diabetics, p=0.1 at 12 months. Overall stroke/death rate in the asymptomatic patients was 2%, and the restenosis rate was higher in the diabetes population (2% versus 1%, p=0.04).

Study focuses on impact of diabetes mellitus on outcomes.

Adil MM, Saeed F, Chaudhary SA et al. (2016) Comparative outcomes of carotid artery stent placement and carotid endarterectomy in patients with chronic kidney disease and end-stage renal disease. Journal of Stroke and Cerebrovascular Diseases 25: 1721–27

Cohort study

n=8,148 (CAS)

Both CAS and CEA were associated with 4-folds higher odds of in-hospital mortality in patients with end-stage renal disease and such observations raise concerns regarding the risk benefit ratio of carotid revascularisation in these patients.

Study focuses on impact of chronic kidney disease on outcomes.

Altibi AM, Saca EE, Dhillon H et al. (2019) Perioperative stroke in carotid artery stenting as a surrogate marker and predictor for 30-day postprocedural mortality - a pooled analysis of 156,000 patients with carotid artery disease. Neurology India 67: 1423-1428

Meta-analysis

n=156,854 symptomatic and asymptomatic patients (146 studies)

Perioperative stroke drastically increases the risk of 30-day mortality. The occurrence of perioperative stroke exhibited high specificity but modest sensitivity in predicting 30-day mortality following CAS.

More recent systematic reviews are included.

Ancetti S, Paraskevas KI, Faggioli G et al. (2021) Effect of carotid interventions on cognitive function in patients with asymptomatic carotid stenosis: a systematic review. European Journal of Vascular and Endovascular Surgery

Systematic review and meta-analysis

n=31 studies (non-randomised)

CEA and CAS rarely improved overall late cognitive function and the risk of significant cognitive decline was equally low (less than 2%). In the long term, most were either unchanged (69%) or mostly unchanged with 1 to 2 test scores improved (25%).

Review focuses on cognitive function.

Arhuidese IJ, Obeid T, Hicks CW et al. (2016) Outcomes after carotid artery stenting in hemodialysis patients. Journal of Vascular Surgery 63: 1511-6

Cohort study

n=1,109

83% asymptomatic

Follow up: median 2.5 years

Overall, 30-day perioperative stroke, myocardial infarction, and death rates were 6%, 6%, and 3%, respectively. Long-term freedom from stroke was 90% at 1 year, 85% at 2 years, and 76% at 4 years. Patient survival was 73% at 1 year and 29% at 4 years. Symptomatic status was the only significant predictor of stroke in a long-term period of 4 years (HR 1.92; 95% CI 1.12 to 3.29; p<0.05).

Study focuses on patients on haemodialysis.

Azzam AY, Ghozy S, Elswedy A et al. (2023) Carotid endarterectomy versus carotid stenting for asymptomatic carotid stenosis: Evaluating the overlapping meta-analyses of randomized controlled trials. European Journal of Radiology Open 10: 100460

Review of meta-analysis studies

n=24,017 (13,835 CAS 10,182 CEA)

5 studies

Carotid endarterectomy reduced the rate of ischemic stroke and stroke-related mortality but led to a higher rate of intraoperative cranial nerve injury. There was no significant difference between carotid endarterectomy and carotid stenting in ipsilateral stroke and myocardial infarction events.

All 5 included meta-analyses are listed in table 5. More recent systematic reviews are included in tables 2 and 3.

Barkat M, Roy I, Antoniou SA et al. (2018) Systematic review and network meta-analysis of treatment strategies for asymptomatic carotid disease.

Scientific Reports 8: 4458

Systematic review and network meta-analysis

n=8,954 (11 trials)

This network meta-analysis demonstrates that CAS and CEA increase the risk of death and ipsilateral stroke at 30 days when compared with best medical therapy. The network meta-analysis results favour CEA in the long term, but this finding is less conclusive.

More recent studies are included.

Batchelder AJ, Saratzis A, Naylor AR (2020) Editor's choice - Overview of primary and secondary analyses from 20 randomised controlled trials comparing carotid artery stenting with carotid endarterectomy. European Journal of Vascular and Endovascular Surgery 58: 479–493

Systematic review

n=3,467 asymptomatic

(7 trials)

CAS confers higher rates of 30 day death or stroke than CEA. After 30 days, ipsilateral stroke is virtually identical for CEA and CAS. Key issues to be resolved include the optimal volume of CAS procedures to maintain competency, how to deliver better risk factor control and BMT and the role of CEA or CAS in preventing or reversing cognitive impairment.

Another systematic review has been summarised, which includes a lot of the same trials.

Bennett KM, Scarborough JE (2017) Carotid artery stenting is associated with a higher incidence of major adverse clinical events than carotid endarterectomy in female patients. Journal of Vascular Surgery 66: 794–801

Registry data

n=5,751 (131 CAS)

290 (5%) patients from the CEA group and 16 (12%) from the CAS group sustained a major adverse clinical event in the first 30 days after their procedures. Within the propensity-matched cohort, this was 11% (14 patients) in the CAS group compared with 4% (5 patients; OR 1.01 [95% CI 1.01 to 7.77]; p=0.04) in the CEA group.

Non-randomised study, focusing on the effect of sex on outcomes.

Bertog SC, Grunwald IQ, Kuhn AL et al. (2013) Complications during carotid artery stenting. Journal of Cardiovascular Surgery 54: 67-82

Review

Complications and adverse events of carotid stenting include those that are related to the vascular access site, vessel spasm, dissection, perforation, thrombotic occlusion and haemodynamic instability and arrhythmias.

Review

Brott TG, Hobson RW, Howard G et al. (2010) Stenting versus endarterectomy for treatment of carotid-artery stenosis. New England Journal of Medicine 363: 11–23

Randomised controlled trial (CREST)

n=2,502

Follow up: median 2.5 years

Among patients with symptomatic or asymptomatic carotid stenosis, the risk of the composite primary outcome of stroke, myocardial infarction, or death did not differ significantly in the group who had CAS and the group who had CEA. During the periprocedural period, there was a higher risk of stroke with stenting and a higher risk of myocardial infarction with endarterectomy.

More recent studies are included.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Brott TG, Howard G, Roubin GS et al. (2016) Long-term results of stenting versus endarterectomy for carotid-artery stenosis. The New England Journal of Medicine 374: 1021-31

Randomised controlled trial (CREST)

n=2,502

Follow up: 10 years

Over 10 years of follow up, the results did not show a significant difference between patients who had stenting and those who had endarterectomy with respect to the risk of periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke. The rate of postprocedural ipsilateral stroke also did not differ between groups.

More recent studies are included.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Carvalho P, Coelho A, Mansilha A (2021) Effectiveness and safety of dual-layer stents in carotid artery disease: A systematic review. International Angiology 40: 97–104

Systematic review

n=1,193 (20 articles)

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

Review focuses on a specific type of stent used for CAS.

Chang C-H, Lin J-W, Lin C-H et al. (2015) Effectiveness and safety of extracranial carotid stent placement: a nationwide self-controlled case-series study. Journal of the Formosan Medical Association 114: 274–81

Case series

n=1,258

Follow up: 360 days

Within 1 year after CAS, 74 patients died and 80 had an ischaemic stroke. Of the 1,184 patients who were followed for 360 days, the RR for ischaemic stroke decreased to 0.21 (95% CI 0.08 to 0.51) between 31 and 180 days and 0.10 (95% CI 0.03 to 0.32) between 181 and 360 days. Statin therapy was associated with a reduced risk of death or ischaemic stroke in the first month (OR 0.53, 95% CI 0.32 to 0.90).

Studies with more patients or longer follow up are included.

Chang H, Rockman CB, Veith FJ et al. (2022) Outcomes of transfemoral carotid artery stenting and transcarotid artery revascularization for restenosis after prior ipsilateral carotid endarterectomy. Journal of Vascular Surgery 75: 561

Non-randomised comparative study

n=3,508 (1,834 transfemoral CAS, 1,674 TCAR)

Among patients having carotid revascularisation for restenosis after prior ipsilateral CEA, TCAR was associated with decreased odds of 30-day transient ischaemic attack compared with transfemoral CAS. However, the 2 treatment approaches were similarly safe in terms of the remaining perioperative outcomes, including stroke and death and stroke, death, and myocardial infarction.

Study focuses on restenosis after previous CEA.

Cho YD, Kim S-E, Lim JW et al. (2018) Protected versus unprotected carotid artery stenting: Meta-analysis of the current literature. Journal of Korean Neurosurgical Society 61: 458–66

Systematic review

n=20,670 CAS procedures

The use of protection device statistically significantly decreased stroke after CAS. However, its efficacy was not demonstrated in symptomatic patients.

Review focuses on the use of cerebral protection devices.

Choi JC, Johnston SC, Kim AS (2015) Early outcomes after carotid artery stenting compared with endarterectomy for asymptomatic carotid stenosis. Stroke 46: 120-5

Cohort study

n=17,716 (3,962 CAS)

For asymptomatic carotid stenosis, CAS is associated with a substantially higher risk of postoperative stroke or in-hospital death than CEA even after adjustment for baseline differences in hospital and patient characteristics.

More recent studies are included.

Choi JH, Pile-Spellman J, Brisman JL (2014) US nationwide trends in carotid revascularization: hospital outcome and predictors of outcome from 1998 to 2007. Acta Neurologica Scandinavica 129: 85–93

Cohort study

The annual number of CEA decreased (137,877 to 111,658) and increased for CAS (2,318 to 14,415). In-hospital mortality after CEA decreased from 0.4% to 0.3% (p<0.001), whereas long-term facility (LTF) discharge increased from 8% to 11% (p<0.001). Discharge outcome improved for CAS in both categories (mortality 2% to 0.5%; LTF discharge 11% to 8%; p<0.001). The trend analysis revealed an increase in patient age and a worsening comorbid profile over time. Age, women, length of stay, atrial fibrillation, and carotid stenosis with infarction were important determinants of unfavourable hospital outcome.

Study assesses trends in carotid revascularisation in the US between 1998 to 2007.

Chu S-S, Hu J, Tang L-W et al. (2021) The impact of diabetes mellitus on carotid artery stenting: a meta-analysis. Neurosurgical Review 44: 3039-3046

Systematic review and meta-analysis

n=3,364

Compared with nondiabetic patients, diabetes did not increase the risk of the following: perioperative stroke, transient ischaemic attack, myocardial infarction, mortality, and composite of stroke or death in patients receiving CAS.

Review focuses on impact of diabetes on outcomes.

Clavel P, Hebert S, Saleme S et al. (2019) Cumulative incidence of restenosis in the endovascular treatment of extracranial carotid artery stenosis: A meta-analysis. Journal of NeuroInterventional Surgery 11: 916–23

Meta-analysis

n=15,943 (40 studies)

This meta-analysis showed a low cumulative rate of restenosis at 12 months and ipsilateral stroke within 30 days after stenting. Older patients and those with hostile neck present a lower risk of in-stent restenosis. The use of an embolic protection device was not associated with a lower risk of stroke.

More recent systematic reviews are included.

Coelho AP, Lobo M, Nogueira C et al. (2019) Overview of evidence on risk factors and early management of acute carotid stent thrombosis during the last two decades. Journal of Vascular Surgery 69: 952–64

Systematic review and meta-analysis

n=60 (29 articles)

Acute carotid stent thrombosis incidence is higher in emergent, neurologically unstable patients. Antiplatelet noncompliance, antiplatelet resistance, long stenotic lesions, use of more than 1 stent, and dual-layer stents are also associated with increased risk.

Review focuses on risk factors for acute carotid stent thrombosis.

Cohen DJ, Stolker JM, Wang K et al. (2011) Health-related quality of life after carotid stenting versus carotid endarterectomy: results from CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial). Journal of the American College of Cardiology 58: 1557–65

Randomised controlled trial (CREST)

n=2,502

CAS is associated with better HRQOL during the early recovery period compared with CEA, particularly regarding physical limitations and pain, but these differences diminish over time and are not evident after 1 year. Although CAS and CEA are associated with similar overall HRQOL at 1 year, event‐specific analyses confirm that stroke has a greater and more sustained impact on HRQOL than myocardial infarction.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Columbo JA, Martinez-Camblor P, Stone DH et al. (2022) Procedural safety comparison between transcarotid artery revascularization, carotid endarterectomy, and carotid Stenting: perioperative and 1-year rates of stroke or death. Journal of the American Heart Association 11 (no. 19)

Registry

n=118,566 (14,595 CAS; 34% asymptomatic)

The perioperative rate of stroke or death for asymptomatic patients was 1% for TCAR, 1% for CEA, and 2% for transfemoral‐CAS (p<0.001).

Symptomatic patients had the most favourable 1‐year result with TCAR, which appears to provide a safe procedural alternative to CEA and CAS for this higher risk cohort.

Study focuses on TCAR as an alternative to CEA and CAS.

Columbo JA, Martinez-Camblor P, MacKenzie TA et al. (2019) A comparative analysis of long-term mortality after carotid endarterectomy and carotid stenting. Journal of Vascular Surgery 69: 104-109

Cohort study

n=33,650 (4,415 CAS; 52% asymptomatic)

The crude HR of all-cause mortality for CEA versus CAS was 0.75 (95% CI 0.70 to 0.81). This survival advantage persisted after adjustment for age, sex, and comorbidities (adjusted HR 0.75; 95% CI 0.69 to 0.82). This effect was confirmed on a propensity-matched analysis, with an HR of 0.76 (95% CI 0.69 to 0.85). Finally, these findings were robust to subanalyses that stratified patients by presenting symptoms and were more pronounced in symptomatic patients (adjusted HR 0.69; 95% CI 0.61 to 0.79) than in asymptomatic patients (adjusted HR 0.80; 95% CI 0.71 to 0.90).

More recent studies are included.

Cui L, Han Y, Zhang S et al. (2018) Safety of stenting and endarterectomy for asymptomatic carotid artery stenosis: a meta-analysis of randomised controlled trials. European Journal of Vascular and Endovascular Surgery 55: 614-624

Systematic review and meta-analysis

n=3,901 (5 studies)

Among patients with asymptomatic carotid stenosis, stenting has a significantly higher rate of any periprocedural stroke and periprocedural minor stroke than CEA, and similar risk of periprocedural major stroke, periprocedural ipsilateral stroke, or myocardial infarction.

More recent systematic reviews are included.

de Vries EE, Meershoek AJA, Vonken EJ et al. (2019) A meta-analysis of the effect of stent design on clinical and radiologic outcomes of carotid artery stenting. Journal of Vascular Surgery 69: 1952-1961e1

Systematic review and meta-analysis

n=46,728 procedures (68 studies)

Stent design is not associated with short- or intermediate-term clinical major adverse event rates in patients who have CAS. Open-cell stenting resulted in a higher number of subclinical postprocedural new ischaemic lesions compared with closed-cell stenting. An individualised patient data meta-analysis, including future studies with prospective homogenous study design, is required to adequately correct for known risk factors and to provide definite conclusions with respect to carotid stent design for specific subgroups.

Review includes symptomatic and asymptomatic patients and focuses on the effect of different stent designs.

DeCarlo C, Tanious A, Boitano LT et al. (2021) Addition of common carotid intervention increases the risk of stroke and death after carotid artery stenting for asymptomatic patients. Journal of Vascular Surgery 74: 1919-1928

Cohort study

n=18,441

The addition of endovascular treatment of common carotid artery lesions with CAS is associated with almost double the risk of perioperative stroke or death in asymptomatic patients and should be avoided if possible.

Study focuses on impact of simultaneous treatment of tandem carotid lesions.

DeCarlo C, Tanious A, Boitano LT et al. (2021) Simultaneous treatment of common carotid lesions increases the risk of stroke and death after carotid artery stenting. Journal of Vascular Surgery 74: 592-598e1

Cohort study

n=1,950

The addition of endovascular treatment of tandem common carotid artery lesions with CAS is associated with a 3-fold increase in perioperative stroke and death and should be avoided if possible.

Study focuses on impact of simultaneous treatment of tandem carotid lesions.

Domanin M, Isalberti M, Romagnoli S et al. (2017) Acute hemifacial ischemia as a late complication of carotid stenting. Journal of Vascular Surgery Cases and Innovative Techniques 3: 83-86

Case report

n=1

Acute hemifacial ischaemia

Case report of late occlusion of the external carotid artery after CAS with symptoms of acute homolateral facial ischaemia as well as pain, cyanosis, tongue numbness, and skin coldness. The patient had local thrombolysis and balloon angioplasty with regression of symptoms after recanalisation.

Case report

Dua A, Romanelli M, Upchurch GR Jr et al. (2016) Predictors of poor outcome after carotid intervention. Journal of Vascular Surgery 64: 663-70

Non-randomised comparative study

n=1,756,445 (7,317 asymptomatic CAS)

For risk-matched asymptomatic and symptomatic patients, female gender (p<0.001) and performing 1 or 2 cases per year (p<0.05) were associated with higher cerebrovascular accident risk. In asymptomatic and symptomatic patients, predictors of myocardial infarction included congestive heart failure (p<0.001) and peripheral artery disease (p<0.05). For both asymptomatic and symptomatic patients, predictors of mortality included female gender (p<0.001) and performing 1 or 2 cases per year (p<0.01).

More recent studies are included.

Dzierwa K, Pieniazek P, Tekieli L et al. (2013) Carotid artery stenting according to the "tailored CAS" algorithm performed in the very elderly patients: The thirty day outcome. Catheterization and Cardiovascular Interventions 82: 681-688

Cohort study

n=1,139

"Tailored CAS" remains a safe procedure for asymptomatic elderly as well as symptomatic and asymptomatic young patients.

Small, non-randomised study focusing on outcomes in very elderly patients.

Faggioli G, Pini R, Rapezzi C et al. (2013) Carotid revascularization in patients with ongoing oral anticoagulant therapy: The advantages of stent placement. Journal of Vascular and Interventional Radiology 24: 370-377

Cohort study

n=1,222 procedures

Follow up: 30 days

Oral anticoagulant therapy management significantly influences the results of carotid revascularisation. Because CAS with unmodified oral anticoagulant therapy had a better outcome than CEA with oral anticoagulant therapy conversion to heparin, carotid revascularisation strategies should favour CAS rather than CEA in this setting.

Small, non-randomised study focusing on management of oral anticoagulant therapy.

Feng Y, Bai X, Li S et al. (2020) Thirty-day outcome of carotid artery stenting in elderly patients: a single-center experience. World Neurosurgery 138: e311-e316

Cohort study

n=1,029

Follow up: 30 days

CAS was safely performed in elderly patients. A family history of stroke, symptomatic status, and modified Rankin Scale score 3 or more indicating a neurologic deficit increased the risk of 30-day postoperative major adverse clinical events.

Small, non-randomised study focusing on short-term outcomes in elderly patients.

Foret T, Guillaumin M, Desmarets M et al. (2022) Association between carotid revascularization for asymptomatic stenosis and cognitive functions. VASA. Zeitschrift fur Gefasskrankheiten 51: 138-149

Systematic review

n=20 studies

Only observational studies analysed the impact of CEA and CAS on cognitive functions.

Data resulting from the analysis were too heterogeneous for a meta-analysis.

No meta-analysis.

Fukushima Y, Nakahara I, Ohta T et al. (2015) Rare complication characterized by late-onset transient neurological symptoms without hyperperfusion after carotid artery stenting: A report of three cases. Interventional Neuroradiology 21: 72-79

Case reports

n=3

Transient neurological symptoms

Case reports of 3 patients who developed neurological symptoms over a period of 10 hours after CAS and improved within 2 days. None of the patients showed signs of fresh infarctions on diffusion-weighted imaging or hyperperfusion on single-photonemission computed tomography.

Case reports

Galinanes EL, Dombroviskiy VY, Hupp CS et al. (2014) Evaluation of readmission rates for carotid endarterectomy versus carotid artery stenting in the US Medicare population. Vascular and Endovascular Surgery 48: 217-23

Non-randomised comparative study

n=235,247 procedures

Readmission rates for patients having CEA and CAS, respectively, were 9% and 11% at 30 days (p<0.0001); 13% and 18% at 60 days (p<0.0001) and 17% and 23% at 90 days (p<0.0001). Patients aged over 80 (OR=1.25; 95% CI 1.20 to 1.30) and patients with renal failure (OR=1.6; 95% CI 1.56 to 1.73), congestive heart failure (OR=1.6; 95% CI 1.57 to 1.73), diabetes (OR=1.4; 95% CI 1.27 to 1.52), and CAS (OR=1.2; 95% CI=1.15 to 1.25) were more likely to be readmitted.

Non-randomised comparative study, assessing readmission rates. More recent studies with longer term follow up are included.

Galyfos G, Sachsamanis G, Anastasiadou C et al. (2019) Carotid endarterectomy versus carotid stenting or best medical treatment in asymptomatic patients with significant carotid stenosis: a meta-analysis. Cardiovascular Revascularization Medicine 20: 413-423

Systematic review and meta-analysis

n=8,771 (10 trials)

CEA is associated with a lower early all stroke risk compared with CAS, although other early or late outcomes did not show any difference between the 2 methods. Additionally, CEA seems to have a benefit over BMT against long-term ipsilateral stroke, although early outcomes are worse after CEA. No studies were available comparing CAS to BMT alone.

More recent systematic reviews are included.

Galyfos G, Geropapas G, Sigala F et al. (2016) Meta-analysis of studies evaluating the effect of cilostazol on major outcomes after carotid stenting. Journal of Endovascular Therapy 23: 186-195

Systematic review and meta-analysis

n=1,297 (7 studies)

Cilostazol seems to decrease total in-stent restenosis rates in patients who have CAS without affecting MI/stroke/death events, both in the early and late settings.

Review assesses effect of cilostazol on outcomes.

Garriboli L, Jannello AM (2015) Delayed carotid wallstent shortening. International Journal of Surgery Case Reports 8: 68-70

Case report

n=1

Follow up: 1 year

Postoperative dislocation of stent

Case report of a postoperative dislocation of a carotid stent that happened 1 year after placement. After the first ultrasound control confirmed the correct position of the stent the following one, 9 months later, showed a severe restenosis because of proximal dislocation of the stent. The problem was solved with the positioning of a further stent more distally.

Case report

Giani L, Lovati C, Rosa S et al. (2015) Episodes of flushing, dyspnea and hypertension after carotid stenting for severe carotid stenosis. Autonomic Neuroscience 193: 147-8

Case report

n=1

Flushing, dyspnoea and palpitations

An 83-year-old woman who had CAS presented with episodes of flushing, dyspnoea and palpitations accompanied by transitory desaturation, hypertension, agitation and anxiety. Symptoms started 12 hours after the procedure. Each episode lasted 10 minutes. Five episodes in 3 days were observed.

Case report

Giri J, Kennedy KF, Weinberg I et al. (2014) Comparative effectiveness of commonly used devices for carotid artery stenting: an NCDR Analysis (National Cardiovascular Data Registry). JACC. Cardiovascular Interventions 7: 171–77

Registry data

n=12,135 procedures

In modern US practice, the Acculink/Accunet, Xact/Emboshield, and Precise/Angioguard carotid stenting systems are mostly used and are associated with similarly low rates of adverse events.

Non-randomised study, comparing different devices.

Goicoechea S, Walsh M, Soult M et al. (2022) Female gender increases risk of stroke and readmission after CEA and CAS. Journal of Vascular Surgery 75: 1935–44

Cohort study

n=106,568 (2,156 CAS) asymptomatic and symptomatic

Female gender was associated with significantly increased rates of postoperative CVA/stroke in the asymptomatic and symptomatic cohorts as well as readmission in the asymptomatic cohort. Female gender was associated with higher rates of CVA/stroke following CEA, but not CAS.

Non-randomised study focusing on the impact of gender on outcomes.

Goode SD, Cleveland TJ, Gaines PA (2013) United Kingdom carotid artery stent registry: Short- and long-term outcomes. CardioVascular and Interventional Radiology 36: 1221-1231

UK registry

n=1,154 (201 asymptomatic)

The 30-day all stroke and death rates for symptomatic patients were 6% and 2% for those with asymptomatic disease. The 30 day mortality rate was 2% for symptomatic and 1% for asymptomatic patients. For symptomatic patients, the 7-year all-cause mortality rate was 22% and for asymptomatic patients 18%. The 7-year all-cause mortality and disabling stroke rates were 25% and 19%, respectively.

More recent studies with more patients are included.

Gorgulu S, Sahin M, Norgaz NT et al. (2022) Carotid artery stenting without embolic protection: a randomized multicenter trial (the CASWEP trial). Interventional neuroradiology 15910199221094388

Randomised controlled trial

n=279

This study suggests that CAS without a carotid protection device is not associated with higher rates of peri‐procedural transient ischaemic attack, stroke, and death or new ischaemic brain lesions compared with CAS with protection in selected symptomatic and asymptomatic patients with significant carotid artery stenosis provided that there is no visible thrombus.

Small trial, assessing the use of carotid protection devices in both symptomatic and asymptomatic patients.

Halliday A, Bulbulia R, Gray W et al. (2013) Status update and interim results from the asymptomatic carotid surgery trial-2 (ACST-2). European Journal of Vascular and Endovascular Surgery 46: 510-518

Randomised controlled trial (ACST-2)

n=986

Follow up: 6 months

Early results suggest contemporary carotid intervention for asymptomatic stenosis has a low risk of serious morbidity and mortality, on par with other recent trials.

A more recent publication from the same trial is included.

Hasan B, Farah M, Nayfeh T et al. (2022) A systematic review supporting the Society for Vascular Surgery Guidelines on the management of carotid artery disease. Journal of Vascular Surgery 75: 99s-108se42

Systematic review and meta-analysis

6 studies on asymptomatic patients (n=5,498)

Medical management compared with carotid interventions in asymptomatic patients was associated with better early outcome during the first 30 days.

More recent studies are included.

Hayashi K, Horie N, Sakamoto I et al. (2014) A case of iliac artery injury treated by covered stent during carotid artery stenting. Acta Neurochirurgica 156: 561-4

Case report

n=1

Iliac artery injury

Case report of iliac artery injury during CAS treated successfully by insertion of a covered stent.

Case report

Heo S-H, Yoon K-W, Woo S-Y et al. (2017) Editor's choice - Comparison of early outcomes and restenosis rate between carotid endarterectomy and carotid artery stenting using propensity score matching analysis. European Journal of Vascular and Endovascular Surgery 54: 573-578

Retrospective non-randomised comparative study

n=1,184

Follow up: mean 49 months

The CAS group showed a relatively higher 30 day incidence of major adverse clinical events (8% versus 2%; OR 3.3, 95% CI 1.63 to 6.51; p=0.001) but a lower incidence of procedure related complications (2% versus 5%; OR 0.20, 95% CI 0.08 to 0.53; p=0.001). During a mean follow up of 49 months (range 1 to 180 months), restenosis rates were higher after CAS than after CEA (2% versus 1% at 12 months and 5% versus 1% at 24 months, respectively, p=0.008).

More recent randomised studies are included.

Hicks CW, Nejim B, Aridi HD et al. (2019) Transfemoral carotid artery stents should be used with caution in patients with asymptomatic carotid artery stenosis. Annals of Vascular Surgery 54: 1–11

Retrospective non-randomised comparative study

n=53,337

Follow up: 2 years

More than one-third of patients who had carotid revascularisation for asymptomatic carotid artery stenosis had 60 to 79% stenosis. Having lower degree of stenosis was not protective against stroke and death for either CEA or CAS at either 30 days or 2 years postoperatively. Optimal medical management should be the first line in stroke prevention for asymptomatic patients with severe (60 to 79%) carotid stenosis.

More recent randomised studies are included.

Hicks CW, Nejim B, Obeid T et al. (2018) Use of a primary carotid stenting technique does not affect perioperative outcomes. Journal of Vascular Surgery 67: 1736-1743e1

Cohort study

n=10,074

Primary carotid stenting is associated with a similar risk of stroke and death compared with conventional CAS with angioplasty. The use of an embolic protection device is essential to good outcomes with both techniques.

Study assesses outcomes of CAS with angioplasty against CAS alone.

Hill MD, Brooks W, Mackey A et al. (2012) Stroke after carotid stenting and endarterectomy in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST). Circulation 126: 3054-3061

Randomised controlled trial (CREST)

n=2,272

Major stroke occurred in 13 (0.6%) patients. The estimated 4‐year mortality after stroke was 21% compared with 12% for those without stroke. The adjusted risk of death at 4 years was higher after periprocedural stroke (hazard ratio, 2.78; 95% CI 1.63 to 4.76).

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Hopkins LN, White CJ, Foster MT et al. (2014) Carotid artery stenting and patient outcomes: the CABANA surveillance study. Catheterization and cardiovascular interventions 84: 997-1004

Prospective cohort study

n=1,097

Follow up: 30 days

The stroke rate (3%) was a major contributing factor in the overall major adverse event rate (5%). Mortality was 1% and the MI rate was 0.5%. There was no statistically significant association between major adverse event rates among the centre experience tiers nor among the operator training categories.

More recent studies with more patients or longer follow up are included.

Howard VJ, Lutsep HL, Mackey A et al. (2011) Influence of sex on outcomes of stenting versus endarterectomy: a subgroup analysis of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST). The Lancet. Neurology 10: 530-537

Randomised controlled trial (CREST)

n=2,502

Periprocedural risk of events seems to be higher in women who have CAS than those who have CEA whereas there is little difference in men. Additional data are needed to confirm whether this differential risk should be considered in decisions for treatment of carotid disease in women.

Primary outcome data from the trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Huang J-H, Kao H-L, Hao W-R et al. (2011) Dislodged self-expanding carotid stent delivery sheath marker ring leading to emergent surgery. Annals of Vascular Surgery 25: e1-264

Case report

n=1

Dislodged stent delivery sheath

Case report in which the metallic marker ring on the delivery sheath dislodged and emergency surgery had to be performed to retrieve the locked stent.

Case report

Huibers AE, Westerink J, de Vries EE et al. (2018) Editor's Choice - Cerebral hyperperfusion syndrome After carotid artery stenting: a systematic review and meta-analysis. European Journal of Vascular and Endovascular Surgery 56: 322-333

Systematic review and meta-analysis

n=8,731 (CAS)

33 studies

The pooled cerebral hyperperfusion risk was 5% (3 to 7%). Stroke occurred in 47% of patients with cerebral hyperperfusion, of which 54% were fatal or disabling. Average time from procedure to symptoms was 12 hours. Impaired cerebrovascular reserve was associated with a higher risk (RR 5.18; 95% CI 1.0 to 26.8; p=0.049). Symptomatic status was associated with a lower risk (RR 0.20; 95% CI 0.07 to 0.59; p=0.001)

Review focuses on cerebral hyperperfusion.

Hung C-S, Yeh C-F, Lin M-S et al. (2017) Impact of hospital volume on long-term neurological outcome in patients undergoing carotid artery stenting. Catheterization and cardiovascular Interventions

Cohort study

n=3,248

Follow up: median 2 years

CAS performed in high‐volume hospitals was associated with less new ischemic stroke after discharging from the index CAS, compared with those in low‐volume hospitals.

Non-randomised study assessing the impact of hospital volume.

Hussain MA, Mamdani M, Tu JV et al. (2018) Long-term outcomes of carotid endarterectomy versus stenting in a multicenter population-based Canadian study. Annals of Surgery 268: 364-373

Cohort study

n=15,525 asymptomatic and symptomatic

Compared with carotid endarterectomy, stenting was associated with an early and sustained approximately 55% increased hazard for major adverse events over long-term follow up. Although non-randomised, these results raise potential concerns about the interchangeability of carotid endarterectomy and stenting in the context of actual clinical practice.

Mixed population of symptomatic and asymptomatic patients.

Hussain MA, Bin-Ayeed SA, Saeed OQ et al. (2016) Impact of diabetes on carotid artery revascularization. Journal of Vascular Surgery 63: 1099-107e4

Systematic review

n=16,264

(14 studies)

Diabetic patients are at an increased risk of perioperative stroke, death, and long-term mortality compared with nondiabetic patients who have carotid artery revascularisation.

Review focuses on impact of diabetes on CAS and CEA.

Hwan Park J, Cho C-S (2022) Early time carotid artery stent shortening: A case report. Interdisciplinary Neurosurgery: Advanced Techniques and Case Management 29: 101597

Case reports

n=2

Stent shortening

2 case reports of the downward shortening of a stent after a CAS procedure, which were detected via computed tomography angiography the day after stenting.

Case report

Jim J, Rubin BG, Ricotta JJ 2nd et al. (2012) Society for Vascular Surgery (SVS) Vascular Registry evaluation of comparative effectiveness of carotid revascularization procedures stratified by Medicare age. Journal of Vascular Surgery 55: 1313-1321

Registry data

n=8,913 (3,397 CAS)

Follow up: 30 days

Compared with CEA, CAS resulted in inferior 30-day outcomes in symptomatic and asymptomatic patients aged 65 years and over. These findings do not support the widespread use of CAS in patients aged 65 years and over.

More recent studies are included.

Jim J, Rubin BG, Landis GS et al. (2011) Society for Vascular Surgery Vascular Registry evaluation of stent cell design on carotid artery stenting outcomes. Journal of Vascular Surgery 54: 71-79

Registry data

n=4,337

Follow up: 30 days

In-hospital and 30-day outcomes after CAS were not significantly influenced by stent cell design. Symptomatic patients had higher adverse event rates compared with the asymptomatic cohort.

More recent studies are included.

Jones MR, Howard G, Roubin GS et al. (2018) Periprocedural stroke and myocardial infarction as risks for long-term mortality in CREST. Circulation. Cardiovascular Quality and Outcomes 11: e004663

Randomised controlled trial (CREST)

n=2,272 asymptomatic and symptomatic

Follow up: 10 years

Patients with periprocedural events demonstrate a substantial increase in future mortality to 10 years. For stroke, this risk is largely confined to an early time frame while periprocedural MI or biomarker-only events confer a continuous increased mortality for 10 years.

Primary outcome data from the trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Jung J-M, Choi J-Y, Kim HJ et al. (2017) Long-term durability and outcomes of carotid stenting and carotid endarterectomy. Journal of NeuroInterventional Surgery 9: 750-755

Systematic review and meta-analysis

n=8,184 (22 studies)

Follow up: maximum 10 years

Although CAS may be more strongly associated with periprocedural stroke/death compared with CEA, it could be a good alternative to CEA in terms of long-term durability and outcomes.

More recent systematic reviews are included.

Kakkos SK, Kakisis I, Tsolakis IA et al. (2017) Endarterectomy achieves lower stroke and death rates compared with stenting in patients with asymptomatic carotid stenosis. Journal of Vascular Surgery 66: 607-617

Systematic review and meta-analysis

n=3,709 (9 trials)

Follow up: 1 year

Among patients with asymptomatic stenosis undergoing carotid intervention, there is moderate-quality evidence to suggest that CEA had significantly lower 30-day stroke and also stroke or death rates compared with CAS at the cost of higher cranial nerve injury and nonsignificantly higher myocardial infarction rates. The long-term efficacy of CEA in ipsilateral stroke prevention, taking into account perioperative stroke and death, was preserved during follow up.

More recent systematic reviews are included.

Kammler J, Blessberger H, Lambert T et al. (2017) In-stent restenosis after interventional treatment of carotid artery stenoses: a long-term follow up of a single center cohort. Clinical Research in Cardiology 106: 493-500

Retrospective cohort study

n=1,165 procedures

Follow up: median 19.6 months

3% (39/1,165) of patients had in-stent restenosis more than 70% during the follow-up period. In 13 of them, restenosis was caused by a mechanical collapse (stent crush) of the implanted stent. All patients were free of neurological events during follow up and 31 patients had a stent-in-stent implantation. A shorter stent length, a narrower stent diameter, performance of post-dilatation as well as stent type significantly influenced development of in-stent restenosis.

Study focuses on in-stent restenosis.

Karpenko A, Bugurov S, Ignatenko P et al. (2021) Randomized controlled trial of conventional versus MicroNet-covered stent in carotid artery revascularization.

JACC: Cardiovascular Interventions 14: 2377-2387

Randomised controlled trial

n=100

Follow up: 30 days

Use of the MicroNet-covered stent in relation to a conventional carotid stent significantly reduced periprocedural cerebral embolism in CAS. Furthermore, cerebral embolism throughout 48 hours to 30 days post-CAS was abolished by the MicroNet-covered stent, while it was ongoing with the conventional single-layer stent.

Small randomised controlled trial, comparing 2 different types of stent.

Karpenko A, Starodubtsev V, Ignatenko P et al. (2020) Comparative analysis of carotid artery stenting and carotid endarterectomy in clinical practice. Journal of Stroke and Cerebrovascular Diseases 29: 104751

Retrospective cohort study

n=2,006

Follow up: 30 days

In the asymptomatic subgroup (n=455), the 30-day rate of stroke was not significantly different between the CEA group and the CAS group (2% in both). The 5-year rate of stroke was not significantly higher for CAS than for CEA (5% versus 3%, p=0.3).

Randomised controlled trials with more asymptomatic patients are included.

Karth PA, Siddiqui S, Garbett D et al. (2013) Branch retinal artery occlusion after internal carotid artery angioplasty and stenting. Retinal Cases and Brief Reports 7: 402-405

Case report

n=1

Branch retinal artery occlusion

The patient developed a branch retinal arterial occlusion with visible emboli 24 hours after CAS and was found to have multiple anastomoses between the external carotid artery and ophthalmic artery because of carotid stenosis. He required a second, emergent angioplastic procedure.

Case report

Keyhani S, Cheng E, Hoggatt K et al. (2022) Comparative effectiveness of carotid stenting to medical therapy among patients with asymptomatic carotid stenosis. Stroke 53: 1157–66

Retrospective cohort study

n=3,060 (551 CAS)

Follow up: 5 years

The observed rate of stroke or death within 30 days in the CAS arm was 2%. Using the target trial methodology, the 5-year risk of fatal and nonfatal stroke was similar among patients assigned to CAS (7%) compared with patients assigned to medical therapy (7%; risk difference, -0.1% [95% CI, -2.6% to 2.7%]). In an analysis that incorporated the competing risk of death, the risk difference between the 2 arms remained nonsignificant (risk difference, -1.5% [95% CI, -3.0% to 0.3%]).

Retrospective non-randomised comparative study.

Khatri R, Chaudhry SA, Vazquez G et al. (2012) Age differential between outcomes of carotid angioplasty and stent placement and carotid endarterectomy in general practice.

Journal of Vascular Surgery 55: 72-8

Non-randomised comparative study

n=495,331 (most were asymptomatic)

For patients who had CAS, age over 70 years was an important predictor of postoperative stroke (p=0.0025; OR 1.7, 95% CI 1.2 to 2.5) and cardiac complications postprocedure (p=0.045; OR 1.3, 95% CI 1.0 to 1.6).

More recent studies are included.

Kim HW, Regenhardt RW, D'Amato SA, et al. (2022) Asymptomatic carotid artery stenosis: a summary of current state of evidence for revascularization and emerging high-risk features. Journal of NeuroInterventional Surgery. doi:10.1136/neurintsurg-2022-018732

Review

Modern medical and surgical advances have continued to improve the outcomes of patients with carotid stenosis. Available decades-old level 1 evidence of asymptomatic carotid artery stenosis treatment has become outdated and new ongoing trials, like CREST-2, are needed to uncover the optimal management. Mounting evidence suggests that imaging-based identification of high-risk features may aid in selecting patients with higher risk who may maximally benefit from surgical revascularisation.

No meta-analysis.

Klarin D, Lancaster RT, Ergul E et al. (2016) Perioperative and long-term impact of chronic kidney disease on carotid artery interventions. Journal of Vascular Surgery 64: 1295-1302

Cohort study

n=12,568 (822 CAS)

60% asymptomatic

For asymptomatic patients, the 30-day mortality among the chronic kidney disease groups were low (0.3% mild versus 1% moderate and 0.4% severe; p=0.004), as were the 30-day stroke rates (2% mild versus 1% moderate and 1% severe; p=0.238). The data suggests that both symptomatic and asymptomatic patients with carotid artery stenosis and chronic kidney disease can be offered intervention when they are carefully selected.

Study focuses on impact of chronic kidney disease.

Kohara K, Ishikawa T, Kobayashi T et al. (2018) Retinal artery occlusion during carotid artery stenting with distal embolic protection device. Neuroradiology Journal 31: 504-508

Case reports

n=2

Retinal artery occlusion

2 case reports of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. It was likely that the debris that caused retinal artery occlusion passed through collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device.

Case reports

Kohat AK, Jayantee K, Phadke RV et al. (2014) Beware of parotitis induced by iodine-containing contrast media. Journal of Postgraduate Medicine 60: 75-76

Case report

n=1

Parotitis induced by iodine-containing contrast media

A 51-year-old man developed multiple small infarcts after a second stenting despite the use of distal protection. He also had painful parotid swelling which improved within a week.

Case report

Kokkinidis D, Chaitidis N, Giannopoulos S et al. (2020) Presence of contralateral carotid occlusion is associated with increased periprocedural stroke risk following CEA but not CAS: a meta-analysis and meta-regression analysis of 43 studies and 96,658 patients. Journal of Endovascular Therapy 27: 334-344

Meta-analysis

n=96,658 (20,801 CAS)

CAS in the presence of a contralateral carotid occlusion is associated with an increased risk of periprocedural death but not stroke or transient ischaemic attack.

Review focuses on impact of contralateral carotid occlusion.

Kuliha M, Roubec M, Prochazka V et al. (2015) Randomized clinical trial comparing neurological outcomes after carotid endarterectomy or stenting. The British Journal of Surgery 102: 194-201

Randomised controlled trial

n=150 (42% asymptomatic)

There was a higher risk of silent infarction in the brain on MRI after CAS in comparison with CEA, but without measurable change in cognitive function.

Small trial, focusing on neurological outcomes.

Kumar R, Batchelder A, Saratzis A et al. (2017) Restenosis after carotid interventions and its relationship with recurrent ipsilateral stroke: a systematic review and meta-analysis. European Journal of Vascular and Endovascular Surgery 53: 766-775

Systematic review and meta-analysis

n=7,201 (11 trials)

CAS patients with untreated asymptomatic more than 70% restenosis had an extremely low rate of late ipsilateral stroke (1% over 50 months). Overall, 97% of all late ipsilateral strokes after CAS and 85% after CEA occurred in patients without evidence of significant restenosis or occlusion.

Review focuses on restenosis after carotid interventions.

Lal BK, Roubin GS, Rosenfield K et al. (2019) Quality assurance for carotid stenting in the CREST-2 Registry. Journal of the American College of Cardiology 74: 3071-3079

Registry

n=2,141

The 30-day rate of composite stroke or death was 1% for asymptomatic, 3% for symptomatic, and 2% for all patients.

Studies with more patients or longer follow up are included.

Lal BK, Roubin GS, Jones M et al. (2019) Influence of multiple stents on periprocedural stroke after carotid artery stenting in the Carotid Revascularization Endarterectomy versus Stent Trial (CREST). Journal of Vascular Surgery 69: 800-806

Cohort study

n=2,652

Strokes occurred in 118 (5%) of all CAS procedures, in 102 (4%) with the use of one stent, and in 16 (15%) with the use of 2 or 3 stents. After adjustment for demographics, lesion characteristics, and risk factors, the use of more than 1 stent resulted in 2.90 odds (95% CI 1.49 to 5.64) for a stroke.

Study focuses on the impact of multiple stents.

Lal BK, Beach KW, Roubin GS et al. (2012) Restenosis after carotid artery stenting and endarterectomy: A secondary analysis of CREST, a randomised controlled trial. The Lancet Neurology 11: 755-763

Randomised controlled trial (CREST)

n=2,191

Follow up: 2 years

In 2 years, 58 patients who had CAS (Kaplan-Meier rate 6%) and 62 who had CEA (6%) had restenosis or occlusion (HR 0.90, 95% CI 0.63 to 1.29; p=0.58). Female sex (1.79, 1.25 to 2.56), diabetes (2.31, 1.61 to 3.31), and dyslipidaemia (2.07, 1.01 to 4.26) were independent predictors of restenosis or occlusion after the 2 procedures.

Secondary analysis of trial that is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Leclerc A, Goia A, Gilard V et al. (2022) Massive non-aneurysmal subarachnoid hemorrhage after cervical carotid angioplasty and stenting: A case report and review of the literature. Neuro-Chirurgie 68: 342-346

Case report

n=1

Massive non-aneurysmal subarachnoid haemorrhage

A 71-year-old man presented a massive non-aneurysmal subarachnoid haemorrhage 1 hour after angioplasty and stenting of the cervical segment of the left internal carotid artery. Medical and surgical management included external ventricular drain placement. Rebleeding occurred 2 days later, worsening the patient's clinical condition. Finally, the patient died 2 weeks later.

Case report

Li Y, Yang J-J, Zhu S-H et al. (2017) Long-term efficacy and safety of carotid artery stenting versus endarterectomy: A meta-analysis of randomized controlled trials. PloS one 12: e0180804

Meta-analysis

n=7,005 (8 trials)

asymptomatic and symptomatic

Carotid endarterectomy was found to be superior to stenting for short- and long-term outcomes, although endarterectomy was associated with a higher risk of periprocedural myocardial infarction. Carotid endarterectomy should be offered as the first choice for carotid stenosis at present, however, more evidence is needed because rapid progress in concurrent devices and medical treatments is being made.

More recent systematic reviews are included.

Liang P, Soden P, Wyers MC et al. (2020) The role of transfemoral carotid artery stenting with proximal balloon occlusion embolic protection in the contemporary endovascular management of carotid artery stenosis. Journal of Vascular Surgery 72: 1701-1710

Retrospective non-randomised comparative study

n=24,232

Compared with transfemoral CAS with distal embolic protection, transfemoral CAS with proximal balloon occlusion has similar major outcomes. However, transfemoral CAS with proximal balloon occlusion does not offer the same degree of embolic protection compared with TCAR with flow reversal, given the significantly higher risk of perioperative stroke or death.

Retrospective analysis, comparing transfemoral CAS using distal protection or proximal balloon occlusion against TCAR with flow reversal.

Lokuge K, de Waard DD, Halliday A et al. (2018) Meta-analysis of the procedural risks of carotid endarterectomy and carotid artery stenting over time. The British Journal of Surgery 105: 26-36

Meta-analysis

n=296,274

(72,961 CAS)

asymptomatic and symptomatic

Procedural stroke and death rates of CAS did not change significantly over time (5% among symptomatic and 3% among asymptomatic patients). There was substantial heterogeneity in event rates and recruitment periods were long.

More recent systematic reviews are included.

Luebke T, Brunkwall J (2016) Carotid artery stenting versus carotid endarterectomy: updated meta-analysis, metaregression and trial sequential analysis of short-term and intermediate-to long-term outcomes of randomized trials. The Journal of Cardiovascular Surgery 57: 519-39

Meta-analysis

asymptomatic and symptomatic

Carotid artery stenting as compared with CEA was associated with a 61% increase in the risk of periprocedural death or stroke (Peto OR 1.6, 95% CI 1.2 to 2.2, p=0.002). Carotid artery stenting as compared with CEA was associated with a 42% increase in the risk for the composite of periprocedural stroke or death plus ipsilateral stroke thereafter (Peto OR 1.4, 95% CI 1.1 to 1.9, p=0.0014).

More recent systematic reviews are included.

Mannheim D, Karmeli R (2017) A prospective randomized trial comparing endarterectomy to stenting in severe asymptomatic carotid stenosis. Journal of Cardiovascular Surgery 58: 814-817

Randomised controlled trial

n=136

Follow up: mean 26 months

There was no difference in short- and long-term results between the 2 groups. Thirty day morbidity included: 1 stroke in each group with no myocardial infarction. Long‐term results included 4 deaths in each group; none from stroke. One transient ischaemic attack was noted after CAS, and there were 3 cases of restenosis after CEA and 1 after CAS.

Small trial, which is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Matsumura JS, Hanlon BM, Rosenfield K et al. (2021) Treatment of carotid stenosis in asymptomatic, non-octogenarian, standard risk patients with stenting versus endarterectomy trials. Journal of Vascular Surgery 75:1276-83

Pooled analysis of 2 trials

n=2,544

Follow up: 4 years

The prespecified, primary composite endpoint of any stroke, myocardial infarction, or death during the periprocedural period or ipsilateral stroke within 4 years after randomisation was 5% in both treatment groups (HR 1.02, 95% CI 0.7 to 1.5, p=0.91). CAS achieved comparable short- and long-term results to CEA.

Data from the 2 trials is included in the systematic review by Müller et al. (2019).

Mazzaccaro D, Giannetta M, Fancoli F et al. (2021) Endovascular treatment of extracranial carotid artery stenosis using a dual-layer micromesh stents: a systematic review. Expert Review of Medical Devices 18: 545-552

Systematic review

n=797 (mostly asymptomatic, 13 papers)

During early follow up, complications occurred overall in 2% (16/797) of patients (12 strokes, 3 deaths, and 1 transient ischaemic attack). The study with the longest follow up reported a survival rate of 82% at 4 years and a stroke-free survival rate of 84% at 4 years.

Review focuses on specific type of stent.

Minc SD, Thibault D, Marone L (2022) Outcomes of carotid artery stenting in patients with radiation arteritis compared with those with atherosclerotic disease. Journal of Vascular Surgery 75: 1286-1292

Cohort study

n=7,218

The CAS patients with radiotherapy had significantly greater mortality at all time points compared with those without it, even after adjusting for other covariates. No significant difference was found in the incidence of perioperative complications, reintervention, or restenosis between the 2 groups. The results suggest that for this high-risk group, CAS provides the same patency as it does for atherosclerotic carotid stenosis and avoids potentially morbid cranial nerve injury and wound healing complications.

Study focuses on patients with carotid stenosis caused by radiation arteritis.

Modrall JG, Chung J, Kirkwood ML et al. (2014) Low rates of complications for carotid artery stenting are associated with a high clinician volume of carotid artery stenting and aortic endografting but not with a high volume of percutaneous coronary interventions. Journal of Vascular Surgery 60: 70-76

Cohort study

n=56,374

The stroke and death rate for CAS to treat carotid stenosis is inversely affected by the number of CAS and endovascular aneurysm repair and thoracic endovascular aortic aneurysm repair procedures done by a clinician. In contrast, a high-volume experience with percutaneous coronary interventions is not associated with improved outcomes after CAS.

More recent studies are included.

Montorsi P, Caputi L, Galli S et al. (2020) Carotid Wallstent versus Roadsaver stent and distal versus proximal protection on cerebral microembolization during carotid artery stenting. JACC. Cardiovascular Interventions 13: 403-414

Randomised controlled trial

n=104

Follow up: 6 months

In patients with high-risk, lipid-rich plaque undergoing CAS, the Mo.Ma device plus Roadsaver stent led to the lowest microembolic signals count.

Small randomised controlled trial, comparing different devices.

Moore WS, Voeks JH, Roubin GS et al. (2019) Duration of asymptomatic status and outcomes following carotid endarterectomy and carotid artery stenting in the Carotid Revascularization Endarterectomy vs Stenting Trial. Journal of Vascular Surgery 69: 1797-1800

Randomised controlled trial

(CREST)

n=1,181 asymptomatic

Follow up: 4 years

In CREST, only a small minority of asymptomatic patients had previous ipsilateral symptoms. The outcomes of periprocedural stroke and death, periprocedural stroke and death, and ipsilateral stroke up to 4 years, and the primary end point did not differ for always asymptomatic patients compared with those who had previous symptoms.

Secondary analysis of trial that is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Moresoli P, Habib B, Reynier P et al. (2017) Carotid stenting versus endarterectomy for asymptomatic carotid artery stenosis: a systematic review and meta-analysis

Stroke 48: 2150-2157

Systematic review and meta-analysis

n=3,019 (11 reports of 5 trials)

The pooled incidences of any periprocedural stroke (RR 1.84; 95% CI 0.99 to 3.40), periprocedural non-disabling stroke (RR 1.95; 95% CI 0.98 to 3.89), and any periprocedural stroke or death (RR 1.72; 95% CI 0.95 to 3.11) trended toward an increased risk after CAS. We could not rule out clinically significant differences between treatments for long-term stroke (RR 1.24; 95% CI 0.76 to 2.03) and the composite outcome of periprocedural stroke, death or myocardial infarction, or long-term ipsilateral stroke (RR 0.92; 95% CI 0.70 to 1.21).

More recent systematic reviews are included.

Nana P, Kouvelos G, Brotis A. et al. (2021) Early outcomes of carotid revascularization in retrospective case series. Journal of Clinical Medicine 10: 1–12

Systematic review and meta-analysis

n=16,043 (15 articles); 68% asymptomatic

CAS did not differ from CEA in terms of stroke (OR 0.98; 0.77 to 1.25; I²=0%), myocardial ischemic events (OR 1.03; 0.72 to 1.48; I²=0%) and all events (OR 1.0; 0.82 to 1.21; I²=0%). Pooled stroke incidence in asymptomatic patients was 1% (95% CI 0 to 2%) for CEA and 1% for CAS (95% CI 0 to 2%). The 2 techniques did not differ in either outcome both in asymptomatic and symptomatic patients.

Other systematic reviews are included.

Nejim B, Mathlouthi A, Weaver L et al. (2020) Safety of carotid artery revascularization procedures in patients with atrial fibrillation. Journal of Vascular Surgery 72: 2069-2078e4

Registry

n=86,778 (95% asymptomatic)

Atrial fibrillation was associated with worse postoperative outcomes in patients with carotid artery disease. Symptomatic status is associated with a stroke or death risk that is higher than in recommended guidelines for CEA and particularly for CAS. Overall, CEA was associated with lower periprocedural intracerebral haemorrhage, mortality, and stroke or death in patients with atrial fibrillation compared with CAS.

Non-randomised study focusing on effect of atrial fibrillation.

Nejim B, Alshwaily W, Dakour-Aridi H et al. (2019) Age modifies the efficacy and safety of carotid artery revascularization procedures. Journal of Vascular Surgery 69: 1490-1503e3

Registry

n=89,853 asymptomatic and symptomatic

The risk of 30-day stroke and 30-day stroke or death did not differ between the 2 procedures in asymptomatic young patients (less than 65 years). However, 30-day stroke and 30-day

stroke or death occurred more often after CAS in asymptomatic patients who were 65 to 75 and 75 years old or older.

The annualised incidence rates of ipsilateral stroke were similar between CAS and CEA in young asymptomatic patients but were higher after CAS in older age groups.

Non-randomised study focusing on effect of age.

Nevidomskyte D, Tang GL, Shin SH et al. (2019) Comparison of outcomes in women and men following carotid interventions in the Washington state's Vascular Interventional Surgical Care and Outcomes Assessment Program. Journal of Vascular Surgery 69: 1121-1128

Cohort study

n=3,704

(45% asymptomatic)

Hospital composite outcome of stroke and mortality following carotid interventions from 2010 to 2015 were noted to be similar for women and men. The notable exception to this finding was observed in a subcohort of women who had CAS for symptomatic carotid disease at age 80 years or older.

Non-randomised study focusing on effect of sex on outcomes.

Nolan BW, De Martino RR et al. (2012) Comparison of carotid endarterectomy and stenting in real world practice using a regional quality improvement registry. Journal of Vascular Surgery 56: 990-6

Registry

n=8,079 procedures (430 CAS)

asymptomatic and symptomatic

Asymptomatic patients had similar rates of stroke or death (CAS 0.7% versus CEA 0.9%, p=0.78) and stroke, death, or myocardial infarction (CAS 1% versus CEA 2%; p=0.40).

More recent studies are included.

Noori VJ, Aranson NJ, Malas M et al. (2021) Risk factors and impact of postoperative hypotension after carotid artery stenting in the Vascular Quality Initiative. Journal of Vascular Surgery 73: 975-982

Retrospective cohort study

n=24,699 (44% asymptomatic)

Hypotension after CAS is associated with adverse neurologic and cardiac events as well as with prolonged length of stay and in-hospital mortality. A scoring tool may be valuable in stratifying patients at risk. Interventions aimed at preventing postoperative hypotension may improve outcomes with CAS.

Study focuses on impact of hypotension after CAS.

Obeid T, Arnaoutakis DJ, Arhuidese I et al. (2015) Poststent ballooning is associated with increased periprocedural stroke and death rate in carotid artery stenting. Journal of Vascular Surgery 62: 616-23e1

Retrospective cohort study

n=3,772 (64% asymptomatic)

The overall perioperative stroke and death rate was 3%. Compared with pre-stent ballooning only technique, the combined pre- and post-stent ballooning technique had a 2.1-fold increase in haemodynamic depression (OR 2.13; 95% CI 1.51 to 3.01, p<0.001) and 2.4-fold increase in perioperative stroke and death rate (OR 2.37; 95% CI 1.01 to 5.62, p<0.050).

Study focuses on the use of post-stent ballooning.

Paraskevas KI, Kalmykov EL, Naylor AR (2016) Stroke/death rates following carotid artery stenting and carotid endarterectomy in contemporary administrative dataset registries: a systematic review. European Journal of Vascular and Endovascular Surgery 51: 3-12

Systematic review

More than 1,500,000 procedures from 21 registries

Data from contemporary administrative dataset registries suggest that stroke and death rates following CAS remain significantly higher than after CEA and often exceed accepted American Heart Association thresholds. There was no evidence of a sustained decline in procedural risk after CAS.

More recent studies are included.

Petr O, Brinjikji W, Murad MH et al. (2017) Selective-versus-standard poststent dilation for carotid artery disease: a systematic review and meta-analysis. AJNR. American Journal of Neuroradiology 38: 999-1005

Systematic review and meta-analysis

n=19,683

(87 studies)

The meta-analysis demonstrated no significant difference in angiographic and clinical outcomes among series that performed standard post-stent angioplasty and those that performed post-stent angioplasty in only select patients.

Study focuses on the use of post-stent angioplasty.

Pieniazek P, Tekieli L, Musialek P et al. (2012) Carotid artery stenting according to the 'tailored-CAS' algorithm is associated with a low complication rate at 30 days: Data from the TARGET-CAS study. Kardiologia Polska 70: 378-386

Case series

n=1,081 (48% asymptomatic)

CAS with embolic protection device and stent type selection on the basis of thorough non-invasive diagnostic work-up ('tailored - CAS') is safe. Advanced age was associated with an increased risk of death and the presence of prior neurological symptoms was a predictor of death/stroke at 30 days. With the 'tailored-CAS' approach, 'high-risk' lesion features are eliminated as a risk factor. Hyperperfusion syndrome is a severe CAS complication which may lead to intracranial bleeding and death. Acute, iatrogenic embolic cerebral artery occlusion is rare and may be managed by combined intracranial mechanical and local thrombolytic therapy.

More recent studies are included.

Pini R, Faggioli G, Gallitto E et al. (2016) Carotid endarterectomy and stenting: A critical analysis of the last randomized controlled trials. Italian Journal of Vascular and Endovascular Surgery 23: 17-25

Meta-analysis of 4 randomised controlled trials

n=5,922 procedures (1,181 asymptomatic)

In asymptomatic patients, there were no statistically significant differences in CEA and CAS groups in terms of death/stroke and death/stroke/myocardial infarction.

More recent trials are included.

Pini R, Faggioli G, Longhi M et al. (2014) Impact of postoperative transient ischemic attack on survival after carotid revascularization. Journal of Vascular Surgery 59: 1570-1576

Retrospective cohort study

n=1,390 procedures

Follow up: 5 years

Overall survival was significantly lower in patients with postoperative transient ischaemic attack (78% versus 97%, p<0.001) and postoperative stroke (68% versus 97%, p=0.03) compared with patients without neurological complications. By means of multivariate Cox analysis, postoperative transient ischaemic attack and stroke were independent predictors of decreased survival (HR 3.10, 95% CI 1.01 to 9.72, p=0.04, and HR 3.87, 95% CI 1.13 to 13.19, p=0.03, respectively), other than age over 80 years, postoperative myocardial infarction, and chronic renal failure (HR 2.07, 95% CI 1.41 to 4.90, p=0.01; HR 4.33, 95% CI 2.74 to 23.79, p=0.04; HR 2.54, 95% CI 1.04 to 6.19, p=0.04, respectively).

More recent studies are included.

Pini R, Faggioli G, Paraskevas KI et al. (2022) Carotid artery stenting with double-layer stent: a systematic review and meta-Analysis. Journal of Endovascular Therapy

Systematic review and meta-analysis

n=1,955 (14 studies)

The overall 30-day stroke rate in CAS with double-layer stents is low (1%), with similar results in symptomatic and asymptomatic patients. Acute occlusion of double-layer stents is rare (1%). Further studies are necessary to reduce the publication bias for asymptomatic patients.

Review focuses on 1 type of stent used for CAS.

Poorthuis MHF, Brand EC, Halliday A et al. (2020) A systematic review and meta-analysis of complication rates after carotid procedures performed by different specialties. Journal of Vascular Surgery 72: 335-343e17

Systematic review and meta-analysis

n=294,638 (38,605 CAS)

35 studies

For CAS, no differences in procedural stroke or death were found by operator specialty.

Review focuses on operator specialty.

Poorthuis MHF, Brand EC, Halliday A et al. (2019) High operator and hospital volume are associated with a decreased risk of death and stroke after carotid revascularization: a systematic review and meta-analysis. Annals of Surgery 269: 631-641

Systematic review and meta-analysis

87 studies

A decreased risk of death or stroke after CAS was found for high operator volume compared with low operator volume with an adjusted OR of 0.43 (95% CI 0.20 to 0.95; 1 cohort), and an unadjusted RR of 0.50 (95% CI 0.32 to 0.79; 1 cohort); for high hospital volume compared with low hospital volume with an adjusted OR of 0.46 (95% CI 0.26 to 0.80; 1 cohort), and no significant decreased risk in a pooled unadjusted RR of 0.72 (95% CI 0.49 to 1.06; 2 cohorts).

Review focuses on operator and hospital volume.

Qureshi AI, Chaudhry SA, Hussein HM et al. (2012) A comparison of outcomes associated with carotid artery stent placement performed within and outside clinical trials in the United States. Journal of Vascular Surgery 56: 317-23

Cohort study

n=81,638

CAS procedures performed as part of clinical trials were associated with lower rates of in-hospital mortality and composite endpoint of stroke, cardiac events, and death in US. These findings highlight the need for strategies that ensure appropriate adoption of CAS to ensure that the benefits observed in clinical trials can be replicated in general practice.

More recent studies are included.

Rahim AA, Thabet MA, Galal AM et al. (2022) Stroke incidence between stenting and endarterectomy for asymptomatic carotid artery stenosis. Annals of Medicine and Surgery 79: 104083

Best evidence topic

6 randomised controlled trials

The best evidence shows no statistically significant difference in the periprocedural and the long-term non-procedural stroke incidence among carotid artery stenting and carotid endarterectomy in asymptomatic carotid artery stenosis. However, in high-risk patients, carotid artery stenting may be a better option.

No meta-analysis.

All 6 trials are included in table 2 or table 5.

Reiff T, Eckstein HH, Mansmann U et al. (2019) Angioplasty in asymptomatic carotid artery stenosis vs. endarterectomy compared to best medical treatment: one-year interim results of SPACE-2. International Journal of Stroke

Randomised controlled trial

n=513

Follow up: 1 year

The low sample size of this prematurely stopped trial of 513 patients implies that its power is not sufficient to show that CEA or CAS is superior to a modern medical therapy in the primary prevention of ischemic stroke in patients with an asymptomatic carotid stenosis up to 1 year after treatment. Also, no evidence for differences in safety between CAS and CEA during the first year after treatment could be derived.

A more recent publication from the same trial is included.

Rockman CB, Garg K, Jacobowitz GR et al. (2011) Outcome of carotid artery interventions among female patients, 2004 to 2005. Journal of Vascular Surgery 53: 1457-64

Cohort study

n=54,658 procedures

Asymptomatic women had a significantly lower perioperative stroke rate after CEA than after CAS (1% versus 2%, p<0.001).

More recent studies are included.

Roh J-H, Cho HJ, Lee J-H et al. (2020) Role of carotid artery stenting in prevention of stroke for asymptomatic carotid stenosis: Bayesian cross-design and network meta-analyses. Korean Circulation Journal 50: 330-342

Network meta-analysis

18 studies

The risk for periprocedural stroke tended to increase in CAS, compared with CEA (OR 1.86; 95% credible interval [CrI], 0.62 to 4.54). However, estimates for periprocedural myocardial infarction were quite heterogeneous. Despite a trend of decreased risk with CAS in randomised controlled trials (OR 0.70; 95% CrI 0.27 to 1.24), the risk was similar in non-randomised comparative studies (OR 1.02; 95% CrI, 0.87 to 1.18). In indirect comparisons of medical treatment and CAS, medical treatments showed a tendency to have a higher risk for the composite of periprocedural death, stroke, myocardial infarction, or nonperiprocedural ipsilateral stroke (OR 1.30; 95% CrI, 0.74 to 2.73).

More recent studies are included.

Rosenfield K, Matsumura JS, Chaturvedi S et al. (2016) Randomized trial of stent versus surgery for asymptomatic carotid stenosis. The New England Journal of Medicine 374: 1011-20

Randomised controlled trial (ACT-1)

n=1,453 (all asymptomatic)

Follow up: 5 years

Stenting was noninferior to endarterectomy with regard to the rate of the primary composite end point at 1 year. In analyses that included up to 5 years of follow up, there were no significant differences between the study groups in the rates of non-procedure-related stroke, all stroke, and survival.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Ruzsa Z, Nemes B, Pintér L et al. (2014) A randomised comparison of transradial and transfemoral approach for carotid artery stenting: RADCAR (RADial access for CARotid artery stenting) study. EuroIntervention 10: 381-391

Randomised controlled trial

n=260

The transradial approach for carotid artery stenting is safe and efficacious; however, the crossover rate is higher with transradial access.

Small trial, comparing 2 different approaches for CAS.

Sannino A, Giugliano G, Toscano E et al. (2018) Double layered stents for carotid angioplasty: A meta-analysis of available clinical data. Catheterization and Cardiovascular Interventions 91: 751-757

Meta-analysis

n=635 (10 studies)

This meta-analysis suggests that dual-layered carotid stents could be safely used for the treatment of extracranial carotid artery stenosis, with a relatively low rate of procedural unsuccess, and allow achieving a quite low rate of postprocedural adverse events.

Review focuses on 1 type of stent used for CAS.

Sardar P, Chatterjee S Aronow H et al. (2017) Carotid artery stenting versus endarterectomy for stroke prevention: a meta-analysis of clinical trials. Journal of the American College of Cardiology 69: 2266-2275

Meta-analysis

n=6,526 (5 trials)

Follow up: mean 5 years

CAS and CEA were associated with similar rates of a composite of periprocedural death, stroke, myocardial infarction, or non-periprocedural ipsilateral stroke. The risk of long-term overall stroke was significantly higher with CAS and was mostly attributed to periprocedural minor stroke. CAS was associated with lower rates of periprocedural myocardial infarction and cranial nerve palsy than CEA.

More recent systematic reviews are included.

Sastry RA, Pertsch NJ, Sagaityte E et al. (2021) Early outcomes after carotid endarterectomy and carotid artery stenting: a propensity-matched cohort analysis. Neurosurgery 89: 653-663

Cohort study

n=84,191 (81,361 CAS)

In a propensity-matched analysis of a large, prospectively collected, national, surgical database, CAS was associated with increased odds of periprocedural stroke, which increased over time. Rates of MI and death were not significantly different between the 2 procedures.

Mixed population of asymptomatic and symptomatic patients.

Schneider EB, Black JH 3^rd, Hambridge HL et al. (2012) The impact of race and ethnicity on the outcome of carotid interventions in the United States. The Journal of Surgical Research 177: 172-7

Cohort study

n=394,835 (47,385 CAS)

Asymptomatic and symptomatic

After CAS, there were no racial or ethnic differences in mortality. On univariate analysis, the risk of stroke was greatest in black patients after CAS (p=0.03). However, this was not significant on multivariable analysis.

Non-randomised study focusing on impact of race and ethnicity.

Shi H, Cai Y, Du J J et al. (2016) Comparative study of stenting and drug treatment in patients with asymptomatic severe internal carotid stenosis. Chinese Journal of Cerebrovascular Diseases 13: 623-628 and 633

Randomised controlled trial

n=200

Patients with unilateral asymptomatic internal carotid artery stenosis have cognitive dysfunction. Compared with the simple drug treatment, CAS combined with drug therapy is more conducive to improving the cognitive function by improving cerebral blood flow perfusion.

More recent and larger trials are included.

Shishehbor MH, Venkatachalam S, Gray WA et al. (2014) Experience and outcomes with carotid artery stenting an analysis of the CHOICE study (carotid stenting for high surgical-risk patients; Evaluating outcomes through the collection of clinical evidence). JACC: Cardiovascular Interventions 7: 1307-1317

Prospective single-arm study (CHOICE)

n=5,841 (mostly asymptomatic)

Operator experience, represented by time-related variables, was closely associated with technical performance and 30-day death, stroke and myocardial infarction. The time interval between CAS procedures and the time from first CAS to subsequent CAS are important measures of operator experience. Technical performance based on embolic protection device dwell time is a statistically significant predictor for 30-day death, stroke and myocardial infarction.

Study focuses on operator experience.

Silver FL, Mackey A, Clark WM et al. (2011) Safety of stenting and endarterectomy by symptomatic status in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST). Stroke; a journal of cerebral circulation 42: 675-680

Randomised controlled trial (CREST)

n=1,181 asymptomatic

Follow up: 4 years

For asymptomatic patients, the stroke and death rates were 3% for CAS and 1% for CEA (HR 1.88; 95% CI 0.79 to 4.42; p=0.15). Rates were lower for those aged less than 80 years.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Simons JP, Goodney PP, Baril DT et al. (2013) The effect of postoperative stroke and myocardial infarction on long-term survival after carotid revascularization. Journal of Vascular Surgery 57: 1581-8

Cohort study

n=8,315 CAS and CEA (65% asymptomatic)

During the first year after operation, postoperative stroke conferred a twofold lower survival than that after postoperative MI. By 5 years after operation, these survival curves converged, and the survival disadvantage associated with stroke became similar to that of MI. These data suggest that different postoperative complications after carotid revascularisation have different implications for patients, with decreased short-term survival in patients experiencing a postoperative stroke.

More recent studies are included.

Simonte G, Fiorucci B, Isernia G et al. (2017) Long-term results of tapered stents in endovascular treatment of carotid stenosis. Annals of Vascular Surgery 45: 79-84

Cohort study

n=1,368 procedures

The use of conic stents appears to be associated with similar perioperative results when compared with straight stents. Late outcomes suggest a lower risk of restenosis and late neurological events in patients with conical shape stents.

Study focuses on specific type of stent.

Stabile E, Giugliano G, Cremonesi A et al. (2016) Impact on outcome of different types of carotid stent: Results from the European Registry of Carotid Artery Stenting. EuroIntervention 12: e265-e270

Registry

n=1,604

Overall, the 30-day stroke and death rate was 1%. At 30 days, 19 strokes occurred (1%): 8 in the group of patients who had a closed-cell (1%), 2 in those with a hybrid-cell (0.4%), 3 in those with a less than 7.5 mm² open cell (1%), and 6 in those treated with a more than 7.5 mm² open-cell stent (3%) (p=0.045).

Study assesses the impact of different kinds of stent.

Stabile E, de Donato G, Musialek P et al. (2018) Use of dual-layered stents in endovascular treatment of extracranial stenosis of the internal carotid artery: results of a patient-based meta-analysis of 4 clinical studies. JACC. Cardiovascular Interventions 11: 2405-2411

Meta-analysis

n=556 (4 studies)

Dual-layered stents can be safely used for CAS, and their use minimises the incremental risk related to symptomatic status and other risk factors.

Review focuses on 1 type of stent used for CAS.

Stabile E, Salemme L, Sorropago G et al. (2010) Proximal endovascular occlusion for carotid artery stenting: results from a prospective registry of 1,300 patients. Journal of the American College of Cardiology 55: 1661-7

Registry

n=1,300

72% asymptomatic

Follow up: 30 days

The use of proximal endovascular occlusion for CAS is safe and effective in an unselected patient population. Anatomical or clinical conditions of high surgical risk were not associated with an increased rate of adverse events.

Study focuses on impact of proximal endovascular occlusion.

Staubach S, Hein-Rothweiler R, Hochadel M et al. (2012) The role of endovascular expertise in carotid artery stenting: results from the ALKK-CAS-Registry in 5,535 patients. Clinical Research in Cardiology 101: 929-37

Registry

n=5,535

47% asymptomatic

The results show a gradual reduction of in-hospital stroke rates with increasing centre experience.

Study focuses on operator experience.

Stolker JM, Mahoney EM, Safley DM et al. (2010) Health-related quality of life following carotid stenting versus endarterectomy: results from the SAPPHIRE (Stenting and Angioplasty with Protection in Patients at HIgh Risk for Endarterectomy) trial. JACC. Cardiovascular interventions 3: 515-523

Randomised controlled trial

n=334

Follow up: 12 months

Among patients at high surgical risk, CAS was associated with less health status impairment during the first 2 weeks of recovery when compared with CEA. However, these differences had resolved by 1 month after the procedure, and no other differences between revascularisation strategies in health‐related quality of life were found.

More recent and larger trials are included.

Sugie A, Yamada M, Yokoyama K et al. (2020) Carotid free-floating thrombus in a stent 6 months after carotid artery stenting. World Neurosurgery 141: 236-239

Case report

n=1

Follow up: 6 months

Carotid free-floating thrombus after CAS

Case report of a 64-year-old man who had CAS for asymptomatic right carotid artery stenosis. Six months after CAS, he was admitted to the emergency department 1 hour after onset of left hemiparesis and dysarthria. His NIHSS score was 10. His medical history was notable for hypertension, chronic renal insufficiency, and type 2 diabetes mellitus. Carotid ultrasonography showed a dumbbell-shaped carotid free-floating thrombus attached to the carotid stent that was moving in synchrony with his heartbeat. It was completely removed using an endovascular approach.

Case report

Sun Y, Ding Y, Meng K et al. (2021) Comparison the effects of carotid endarterectomy with carotid artery stenting for contralateral carotid occlusion. PloS one 16: e0250580

Systematic review and meta-analysis

n=6,953 (6 studies)

asymptomatic and symptomatic

This study found that CEA and CAS resulted in similar outcomes for patients with contralateral carotid occlusion, while the risk of death was reduced in patients treated with CEA.

Review focuses on impact of contralateral carotid occlusion.

Tekieli L, Musialek P, Kablak-Ziembicka A et al. (2019) Severe, recurrent in-stent carotid restenosis: Endovascular approach, risk factors. Results from a prospective academic registry of 2637 consecutive carotid artery stenting procedures (TARGET-CAS). Postepy w Kardiologii Interwencyjnej 15: 465-471

Registry

n=2,637

Follow up: minimum 12 months

Endovascular treatment of carotid in-stent restenosis is safe. Bilateral and high-grade carotid artery stenosis may increase the risk of restenosis.

Study focuses on recurrent in-stent restenosis.

Texakalidis P, Chaitidis N, Giannopoulos S et al. (2019) Carotid revascularization in older adults: a systematic review and meta-analysis. World Neurosurgery 126: 656-663

Systematic review and meta-analysis

n=5,955 (9 studies)

This study shows that CEA is associated with a statistically significant lower risk of 30-day stroke in the elderly population compared with transfemoral CAS with distal or proximal protection. No differences were noted in the rates of periprocedural transient ischaemic attack, myocardial infarction, death, and cranial nerve injury between CEA and CAS in the original pooled analysis.

Review focuses on outcomes in adults aged over 80 years.

Texakalidis P, Tzoumas A, Giannopoulos S et al. (2019) Risk factors for restenosis after carotid revascularization: a meta-analysis of hazard ratios. World Neurosurgery 125: 414-424

Systematic review and meta-analysis

n=17,106 (18 studies)

Diabetes, dyslipidemia, female gender, renal failure, hypertension, and smoking were associated with an increased risk of restenosis, and patch endarterectomy and symptomatic status at presentation were associated with a decreased risk of carotid restenosis. Both female gender and current smoking status were only associated with recurrent stenosis after CEA, and hypertension was only associated with restenosis after CAS.

More recent systematic reviews are included.

Texakalidis P, Giannopoulos S, Kokkinidis DG et al. (2018) Carotid artery endarterectomy versus carotid artery stenting for patients with contralateral carotid occlusion: a systematic review and meta-analysis. World Neurosurgery 120: 563-571e3

Systematic review and meta-analysis

n=6,346 (5 studies)

Subgroup analyses of symptomatic and asymptomatic patients did not yield significant differences for stroke, MI, and death.

Patients with contralateral carotid occlusion can safely undergo both CAS and CEA with similar risks of stroke, MI, and major adverse clinical events. However, patients treated with CEA have a lower risk of 30-day periprocedural mortality.

Review focuses on impact of contralateral carotid occlusion.

Timaran CH, Mantese VA, Malas M et al. (2013) Differential outcomes of carotid stenting and endarterectomy performed exclusively by vascular surgeons in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST). Journal of Vascular Surgery 57: 303-308

Randomised controlled trial (CREST)

n=1,181 asymptomatic

When performed by surgeons, CAS and CEA have similar net outcomes, although the periprocedural risks vary (lower stroke with CEA and lower myocardial infarction with CAS). These data suggest that appropriately trained vascular surgeons may safely offer both CEA and CAS for the prevention of stroke.

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Tomai F, De Persio G, Petrolini A et al. (2017) Acute pseudoaneurysm following carotid artery stenting. JACC. Cardiovascular Interventions 10: 622-623

Case report

n=1

Pseudoaneurysm

7 days after CAS, the patient had a pulsatile neck mass and CT showed 2 large pseudoaneurysms at both proximal and distal stent edges, requiring urgent endovascular treatment. Two overlapping stents were implanted with complete exclusion of the pseudoaneurysms, without any complication.

Case report

Tsai M-L, Mao C-T, Chen D-Y et al. (2015) Short- and long-term major cardiovascular adverse events in carotid artery interventions: A nationwide population-based cohort study in Taiwan. PLoS ONE 10: e0121016

Cohort study

n=2,849

Follow up: mean 2.5 years

Periprocedural acute renal failure significantly increased the mortality rate and the number of major adverse cardiovascular events, and the predict power persisted more than 1 year after the procedure. Age and diabetes mellitus were significant risk factors to predict acute myocardial infarction after carotid artery stenting.

More recent or larger studies are included.

Turley RS, Freischlag K, Truong T et al. (2019) Carotid stenting and endarterectomy and contralateral carotid occlusion. Journal of Vascular Surgery 70: 824-831

Non-randomised comparative study

n=12,370 procedures (422 CAS)

There is currently a bias that contralateral carotid occlusion confers a higher risk on patients undergoing carotid procedures and this notion is manifest in the proportion of CEA and CAS procedures done in the setting of contralateral carotid occlusion. This study observes that it provides only a minor influence on periprocedural stroke risk and that other factors are more closely tied to outcomes of CEA and CAS.

Non-randomised study, focusing on impact of contralateral carotid occlusion.

Varetto G, Frola E, Gibello L et al. (2019) A rare nitinol double-layer micromesh carotid stent complication: late thrombosis-first case reported in literature. Annals of Vascular Surgery 58: 380

Case report

n=1

Late thrombosis

Case report of a 66-year-old female patient treated for asymptomatic carotid stenosis complicated by a symptomatic partial stent thrombosis occurred 3 months after carotid artery stenting.

Case report

Voeks JH, Howard G, Roubin GS et al. (2011) Age and outcomes after carotid stenting and endarterectomy: the carotid revascularization endarterectomy versus stenting trial. Stroke 42: 3484-90

Randomised controlled trial (CREST)

n=2,502

For CAS, risk for the primary end point increased with age (p<0.0001) by 1.77-times (95% CI 1.38 to 2.28) per 10-year increment; however, there was no evidence of increased risk for CEA-treated patients (p=0.27). Stroke events were the primary contributor to the overall effect modification (p interaction=0.033), with equal risk at 64 years. The treatment-by-age interaction for CAS and CEA was not altered by symptomatic status (p=0.96) or by sex (p=0.45).

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

Watanabe M, Chaudhry Saqib A, Adil MM et al. (2015) The effect of atrial fibrillation on outcomes in patients undergoing carotid endarterectomy or stent placement in general practice. Journal of Vascular Surgery 61: 927-32

Cohort study

n=672,074 mostly asymptomatic

80,878 CAS

The analysis suggests that almost 10% of CAS and CEA is done in patients with atrial fibrillation in general practice, and higher rates of adverse events are observed among these patients, particularly those who have CEA.

Study focuses on effect of atrial fibrillation on outcomes.

Weinberg I, Beckman JA, Matsumura JS et al. (2018) Carotid stent fractures are not associated with adverse events results from the ACT-1 multicenter randomized trial (carotid angioplasty and stenting versus endarterectomy in asymptomatic subjects who are at standard risk for carotid endarterectomy with significant extracranial carotid stenotic disease). Circulation 137: 49-56

Randomised controlled trial (ACT-1)

n=1,021

Follow up: mean 3 years

Of 1021 patients, 939 had at least 1 X-ray during the follow-up period. Stent fracture was reported in 51 (5%) patients. With a maximum follow-up period of 5 years, adverse clinical outcomes occurred in 39 patients with at least 1 X-ray during the follow-up. Of 826 (81%) patients who had both duplex ultrasound and X-ray, 822 were interpretable. There was no association between stent fracture and the primary end point (p=0.86) or with restenosis (p=0.53)

Trial is included in systematic reviews by Wang et al. (2022) and Müller et al (2019).

White CJ, Brott TG, Gray WA et al. (2022) Carotid artery stenting: JACC state-of-the-art review. Journal of the American College of Cardiology 80: 155-170

Review

The review supports a recommendation to approve CAS in selected candidates who are symptomatic with a carotid stenosis between 50% and 99% and for asymptomatic patients with carotid stenosis between 70% and 99% for stroke prevention. Optimised CAS strategies have allowed experienced operators to better assess procedure risk before CAS and have led to continued improvement in CAS outcomes. New technologies including enhanced embolic protection devices and dual-layered stents should result in further improvement.

Other systematic reviews are included.

Xin W, Yang S, Li Q et al. (2021) Endarterectomy versus stenting for the prevention of periprocedural stroke or death in patients with symptomatic or asymptomatic carotid stenosis: a meta-analysis of 10 randomized trials. Annals of Translational Medicine 9: 256

Systematic review and meta-analysis

n=9,527 (10 trials)

2,770 asymptomatic

Among patients with asymptomatic CS, the rates of minor stroke and stroke in general were higher with stenting than with CEA. Based on the current data, CEA is more beneficial than CAS for 30-day stroke prevention.

A more recent systematic review is included.

Young KC, Jahromi BS (2011) Does current practice in the United States of carotid artery stent placement benefit asymptomatic octogenarians? AJNR. American Journal of Neuroradiology 32: 170-3

Cohort study

n=249,592 (31,197 CAS)

CAS is independently associated with increased in-hospital stroke or death (excluding cardiac complications from the composite outcome). In those 80 years old and above, CAS as currently performed may not improve the natural history of asymptomatic carotid stenosis, because in-hospital stroke or death rates following CAS approached 3% in this group.

More recent studies are included.

Yuan G, Zhou S, Wu W et al. (2018) Carotid artery stenting versus carotid endarterectomy for treatment of asymptomatic carotid artery stenosis. International Heart Journal 59: 550-558

Systematic review and meta-analysis

n=4,414 (5 studies)

The results suggested that CAS is associated with significantly lower risk of MI and a slightly higher risk of stroke than those with CEA. Both procedures seemed equivalent in terms of the risk of death. In the subgroup analysis, decreased risk of MI after CAS was significant only in the mixed patient group but not in the asymptomatic patient group, whereas the risk of stroke after CAS remained higher in both the mixed and asymptomatic groups.

More recent systematic reviews are included.

Yuo TH, Sidaoui J, Marone LK et al. (2015) Revascularization of asymptomatic carotid stenosis is not appropriate in patients on dialysis. Journal of Vascular Surgery 61: 670-674

Cohort study

n=2,131 asymptomatic (326 CAS)

Patients on dialysis have high perioperative and long-term stroke or death rates after CEA or CAS for asymptomatic stenosis, with a median survival that is less than recommended by current guidelines. As a result, carotid intervention in these patients appears to be inappropriate.

Study focuses on patients on dialysis.

Zapata-Arriaza E, Moniche F, Gonzalez A et al. (2016) Predictors of restenosis following carotid angioplasty and stenting. Stroke 47: 2144-7

Cohort study

n=1,060

Follow up: median 12 months

9% (97) of patients experienced restenosis during follow up. Occurrence of restenosis was associated with ipsilateral stroke during follow up p=0.049). After Cox regression analysis, hypertension (HR 6.2; 1.9 to 19.9; p=0.002), impaired vasoreactivity (HR 1.7; 1.09 to 2.8; p=0.019), and angioplasty without stent (HR 2.9; 1.2 to 6.8; p=0.012) were independent risk predictors of more than 70% restenosis.

Larger or more recent studies are included.

Zevallos CB, Farooqui M, Quispe-Orozco D et al. (2022) Acute carotid artery stenting versus balloon angioplasty for tandem occlusions: a systematic review and meta-analysis. Journal of the American Heart Association 11: e022335

Systematic review and meta-analysis

n=3,014 (34 studies)

Carotid artery stenting and a retrograde approach had higher odds of successful reperfusion and good functional outcomes at 3 months than balloon angioplasty and an anterograde approach, respectively, in patients with tandem occlusions. A randomised controlled trial comparing these techniques with structured antithrombotic regimens and safety outcomes will offer definitive guidance in the optimal management of this complex disease.

Review focuses on the effect of tandem occlusions on outcomes.