A cost-effectiveness analysis of carotid artery stenting compared with endarterectomy

Complication-Specific In-Hospital Costs After Carotid Endarterectomy vs Carotid Artery Stenting

Purpose: To quantify and compare the incremental cost associated with in-hospital stroke, death, and myocardial infarction (MI) after carotid endarterectomy (CEA) vs carotid artery stenting (CAS). Methods: A retrospective analysis was performed of 100,185 patients (mean age 70.7±9.5 years; 58.3% men) who underwent CEA (n=86,035) or CAS (n=14,150) between 2009 and 2015 and were entered into the Premier Healthcare Database. Multivariate logistic models and generalized linear models were used to analyze binary outcomes and hospitalization costs, respectively. Outcomes are presented as the adjusted odds ratio (aOR) and 95% confidence interval (CI). Results: CAS was associated with 1.6 times higher adjusted odds of stroke [aOR 1.55 (95% CI 1.36 to 1.77), p<0.001] and with 2.6 times higher odds of death [aOR 2.60 (95% CI 2.14 to 3.17), p<0.001] compared with CEA. There was no significant difference in MI risk between the 2 procedures. The adjusted incremental cost of death and MI were similar between the 2 procedures. However, the adjusted incremental cost of stroke was significantly higher in CEA compared with CAS by an estimated $2000. When stratified with respect to symptomatic status, the increased adjusted incremental cost of stroke in CEA was mainly seen in asymptomatic patients ($5284 vs $2932, p<0.01). Conclusion: The incremental cost of in-hospital stroke is relatively higher in CEA compared to CAS. However, CEA remains a more cost-effective carotid intervention due to lower complication rates and baseline costs compared with CAS. Long-term cost-effectiveness studies are needed before definite conclusions are made.

Meta-analysis of the procedural risks of carotid endarterectomy and carotid artery stenting over time

Background

Stroke/death rates within 30 days of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in RCTs inform current clinical guidelines. However, the risks may have changed in recent years with wider use of effective stroke prevention therapies, especially statins, improved patient selection and growing operator expertise. The aim of this study was to investigate whether the procedural stroke/death risks from CEA and CAS have changed over time.

Methods

MEDLINE and Embase were searched systematically from inception to May 2016 for observational cohort studies of CEA and CAS. Studies included reported on more than 1000 patients, with 30‐day outcomes after the procedure according to patients' symptom status (recent stroke or transient ischaemic attack). Restricted maximum likelihood random‐effects and meta‐regressions methods were used to synthesize procedural stroke/death rates of CEA and CAS according to year of study recruitment completion.

Results

Fifty‐one studies, including 223 313 patients undergoing CEA and 72 961 undergoing CAS, were reviewed. Procedural stroke/death risks of CEA decreased over time in symptomatic and asymptomatic patients. Risks were substantially lower in studies completing recruitment in 2005 or later, both in symptomatic (5·11 per cent before 2005 versus 2·68 per cent from 2005 onwards; P = 0·002) and asymptomatic (3·17 versus 1·50 per cent; P < 0·001) patients. Procedural stroke/death rates of CAS did not change significantly over time (4·77 per cent among symptomatic and 2·59 per cent among asymptomatic patients). There was substantial heterogeneity in event rates and recruitment periods were long.

Conclusions

Risks of procedural stroke/death following CEA appear to have decreased substantially. There was no evidence of a change in stroke/death rates following CAS.

Endarterectomy outcomes improving

Risk factors and preventive measures of cerebral hyperperfusion syndrome after carotid artery interventional therapy

This study sought to investigate the risk factors for cerebral hyperperfusion syndrome (CHS) after carotid artery interventional therapy, and to explore potential preventive measures. Three hundred and eighty-two patients treated with carotid artery stenting at the Huanhu Hospital (Tianjin, China) between January 2010 and January 2016 were divided into CHS and non-CHS groups. A retrospective analysis of patient clinical data was made. The CHS group had more patients presenting coronary heart disease, diabetes, progressive neurological disease and transient recurrent cerebral hemorrhage than the non-CHS group. More patients in the CHS group presented stenosis of the internal carotid artery siphon. More CHS group patients showed plaque formation extending >3 cm to the distal end of the internal carotid artery. Finally, more CHS group patients had pressure gradients >60 mmHg (p<0.05). Logistics regression analysis showed that preoperative diabetes mellitus and carotid pressure gradient ≥60 mmHg were independent risk factors for CHS (p<0.05). The ROC curve of carotid pressure gradients ≥60 mmHg were made to predict CHS, with the area under curve being 0.949 (p<0.05). The best cut-off value was 60 mmHg. Therefore, preoperative diabetes and a carotid pressure gradient ≥60 mmHg are risk factors for CHS, and these indicators need to be examined prior to operation.

The role of cost-effectiveness for vascular surgery service provision in the United Kingdom

OBJECTIVE

The cost of health care is increasingly becoming an international issue, with many health care systems requiring evaluation of cost when agreeing to fund health care. In the United Kingdom (UK), for example, the National Institute for Health and Care Excellence highlights the importance of using cost-effectiveness analyses to facilitate the effective use of resources. This study evaluates the use of cost-effectiveness analyses and the provision of vascular surgery.

METHODS

A systematic review of published literature was performed. UK-based studies assessing cost-effectiveness or cost-utility of superficial venous interventions, abdominal aortic aneurysm (AAA) repair, and carotid endarterectomy (CEA) were included. All included studies were quality assessed to determine the overall strength of UK economic evidence for each intervention.

RESULTS

Four superficial venous, six AAA, and two CEA studies met the inclusion criteria. After quality assessment, the UK evidence supporting the cost-effectiveness of superficial venous intervention was graded strong. The economic evidence for asymptomatic and symptomatic CEA was graded limited and insufficient, respectively, owing to a paucity of UK literature in this field. There was strong UK economic evidence affirming that endovascular aneurysm repair (EVAR) is unlikely to be a cost-effective alternative to open repair.

CONCLUSIONS

There is strong economic evidence for symptomatic superficial venous intervention. However, funding for varicose vein treatments remains controversial. Future economic analyses are required for symptomatic and asymptomatic CEA to better advise national policy. Despite strong economic evidence, current UK guidance is for EVAR over open repair in the elective setting, with the majority of elective AAA repairs being EVAR.

Optimal contemporary management of symptomatic and asymptomatic carotid artery stenosis

This commentary addresses the issue of optimal contemporary management of symptomatic and asymptomatic carotid artery stenosis. Based on current data, carotid endarterectomy (CEA) should be performed in the majority of patients with symptomatic carotid artery stenosis. Carotid artery stenting (CAS) should be reserved for a minority of these symptomatic patients, in whom CEA is contraindicated. In asymptomatic patients, all should be placed on best medical treatment (BMT). With the use of one or more of the proposed stroke risk stratification models or some as yet undetermined method, the identification of those asymptomatic individuals may be possible in whom stroke risk is higher than usual with BMT. This asymptomatic subgroup, which may be small and is yet to be determined with certainty, could be offered an invasive carotid procedure (either CAS or CEA).

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Evaluation of readmission rates for carotid endarterectomy versus carotid artery stenting in the US Medicare population

OBJECTIVE

We evaluated rates and identified predictors of readmission in the Medicare population after carotid endarterectomy (CEA) compared to carotid artery stenting (CAS).

METHODS

MedPAR data (2005-2009) were used to select patients who underwent CEA or CAS (utilizing International Classification of Diseases, Ninth Revision, Clinical Modification codes). Readmission was evaluated using chi-square and multivariable logistic regression.

RESULTS

A total of 235 247 carotid interventions were performed (211 118 CEA and 24 129 CAS). Readmission rates (%) for patients undergoing CEA and CAS, respectively, were 8.84 and 11.11 (30 days; P < .0001); 13.31 and 17.98 (60 days; P < .0001); and 16.86 and 22.68 (90 days; P < .0001). Patients aged >80 (odds ratio [OR] = 1.25; 95% confidence interval [CI] = 1.20-1.30) and patients with renal failure (OR = 1.6 95%; CI = 1.56-1.73), congestive heart failure (OR = 1.6; 95%CI = 1.57-1.73), diabetes (OR = 1.4; 95% CI 1.27-1.52), and CAS (OR = 1.2; 95%CI = 1.15-1.25) were more likely to be readmitted.

CONCLUSIONS

Interventions for carotid artery disease had high overall readmission rates. After adjustment for comorbidities, utilization of less invasive techniques (CAS) did not result in lower readmission rates. Further evaluation is needed to determine strategies to reduce hospital readmission rates after carotid interventions.

Limited economic evidence of carotid artery stenosis diagnosis and treatment: a systematic review

The objective of this article is to assess the availability and validity of economic evaluations of carotid artery stenosis (CS) diagnosis and treatment.

DESIGN

Systematic review of economic evaluations of the diagnosis and treatment of CS.

METHODS

Systematic review of full economic evaluations published in Medline and Google Scholar up until 28 February 2012. Based on economic checklists (Evers and Philips), the identified studies were classified as high, medium, or low quality.

RESULTS

Twenty-three evaluations were identified. The study quality ranged from 26% to 84% of all achievable points (Evers). Seven studies were of high, eight of medium and eight of low quality. No comparison was made between carotid angioplasty and stenting (CAS) and best medical treatment (BMT). For subjects with severe stenosis, comparisons of carotid endarterectomy (CEA) and BMT were also missing. Three of five studies dealing with pre-operative imaging found that duplex Doppler ultrasound (US) was cost-effective compared with carotid angiogram (AG).

CONCLUSIONS

There is a huge lack of high-quality studies and of studies that confirm published results. Also, for a given study quality, the most cost-effective treatment strategy is still unknown in some cases ('CAS' vs. 'BMT', 'US combined with magnetic resonance angiography supplemented with AG' vs. 'US combined with computer tomography angiography').

Evidence-based treatment of carotid artery stenosis

Carotid atheromatous disease is an important cause of stroke. Carotid endarterectomy (CEA) is a well-established option for reducing the risk of subsequent stroke due to symptomatic stenosis (> 50%). With adequately low perioperative risk (< 3%) and sufficient life expectancy, CEA may be used for asymptomatic stenosis (> 60%). Recently, carotid angioplasty and stent placement (CAS) has emerged as an alternative revascularization technique. Trial design considerations are discussed in relation to trial results to provide an understanding of why some trials were considered positive whereas others were not. This review then addresses both the original randomized studies showing that CEA is superior to best medical management and the newer studies comparing the procedure to stent insertion in both symptomatic and asymptomatic populations. Additionally, recent population-based studies show that improvements in best medical management may be lowering the stroke risk for asymptomatic stenosis. Finally, the choice of revascularization technique is discussed with respect to symptom status. Based on current evidence, CAS should remain limited to specific indications.

Carotid endarterectomy plus medical therapy or medical therapy alone for carotid artery stenosis in symptomatic or asymptomatic patients: a meta-analysis

OBJECTIVE

The purpose of this study was to compare carotid endarterectomy (CEA) plus medical therapy (MT) with MT alone for symptomatic and asymptomatic patients suffering from carotid artery stenosis in terms of long-term stroke/death rate.

DESIGN

A meta-analysis of parallel randomized, controlled trials (RCTs) (blind or open) published in English.

SETTING

A university-based electronic search.

PARTICIPANTS

Patients suffering from carotid artery stenosis symptomatic or not.

INTERVENTIONS

Patients were subjected to CEA plus MT or MT alone.

MEASUREMENTS AND MAIN RESULTS

For asymptomatic patients, 6 RCTs comprising 5,733 patients (CEA = 2,853 and MT = 2,880) were included. CEA did not affect the stroke/death risk for asymptomatic patients (risk ratio [RR] = 0.93; 95% confidence interval [CI], 0.84 to 1.02; I(2) = 0%; p = 0.14). For symptomatic patients, 2 RCTs were included. They had 5,627 patients (CEA = 3,069 and MT = 2,558) of whom 2,295 patients (CEA = 1,213; MT = 1,082) had severe stenosis (North American Symptomatic Carotid Endarterectomy Trial [NASCET] technique ≥50% and European Carotid Surgery Trial technique ≥70%). CEA decreased the stroke/death risk only for patients with severe stenosis (RR = 0.69; 95% CI, 0.59-0.81; p < 0.001 [random effects model]; I(2) = 0% on the odds ratio and 17% on the RR [benefit or harm side]; number needed to treat = 11 [95% CI, 8-17]).

CONCLUSIONS

CEA is helpful for recently symptomatic patients with carotid artery stenosis ≥50% (NASCET technique) but adds no benefit in terms of stroke/death for asymptomatic patients.

Carotid endarterectomy: still the standard of care for carotid bifurcation disease

Current treatment guidelines of symptomatic and asymptomatic carotid stenosis are based on studies performed over a decade ago. Since that time, significant advances have been made in medical management, namely high dose statin therapy and improved antiplatelet agents, and in carotid interventions, namely the advent of carotid artery stenting. Especially with carotid stenting, the technology has grown by leaps and bounds and continues to advance at a rapid pace. These advances have necessitated new studies to compare these treatments with the gold standard of carotid endarterectomy. In asymptomatic patients, the current data does not justify medical management alone for severe (>80%) carotid stenosis. Furthermore, in both asymptomatic and symptomatic patients current studies have failed to demonstrate equivalence of CAS to CEA for significant carotid stenosis. Clearly additional studies comparing CAS, CEA, and medical management are needed to further clarify this issue. In the future, advances in CAS technology and techniques may greatly expand the role of CAS beyond its current role in certain high-risk patient subsets. However, for the time being CEA still remains the gold standard for carotid intervention.

Does current practice in the United States of carotid artery stent placement benefit asymptomatic octogenarians?

BACKGROUND AND PURPOSE

CAS or CEA for asymptomatic carotid stenosis is the focus of recently completed and ongoing randomized clinical trials. These techniques are widely utilized outside the setting of such trials. Therefore, our goal was to analyze the in-hospital stroke or death rates after CAS or CEA for asymptomatic stenosis that reflect current nationwide practice.

MATERIALS AND METHODS

Using sample-weighted ANOVA, we analyzed records from the 2006 and 2007 NIS, which are nationally representative cohorts for asymptomatic CAS or CEA. The primary outcome measure was a composite end point of in-hospital stroke, cardiac complications, or death. In-hospital stroke or death was a secondary outcome measure.

RESULTS

For ≥ 80 years of age, the in-hospital stroke, cardiac complications, or death rate after CAS was 4.9%, while the complication rate after CEA was 3.8%. The stroke or death rate after CAS was 2.7% for ≥ 80 years of age and was 1.5% after CEA for the same age group. Multivariate analysis showed that age (OR, 1.12; 95% CI, 0.97-1.3; P < .07) or procedure (OR, 1.12; 95% CI, 0.99-1.27; P < .14) was not associated with the composite end point of in-hospital stroke, cardiac complications, or death. In contrast, CAS (OR, 1.28; 95% CI, 1.03-1.58) and female sex (OR, 1.23; 95% CI, 1.04-1.45) were independently associated with in-hospital stroke or death following asymptomatic carotid revascularization. Hospital charges and hospital costs were lower for CEA than CAS (2007 costs: $7779 versus $12,104).

CONCLUSIONS

CAS is independently associated with increased in-hospital stroke or death (excluding cardiac complications from the composite outcome). In those ≥ 80 years of age, 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.