Current practice of carotid endarterectomy in the UK

Early-Term Complications after Carotid Endarterectomy and Their Risk Factors: Eight-Year Employment of Local Treatment Protocol of a Russian High-Volume Center

BACKGROUND

More than 20,000 carotid endarterectomies are performed annually in the Russian Federation. Until now, no studies based on the national carotid data set have been published. The objectives of this study were to evaluate early outcomes after carotid endarterectomy and to identify potential risk factors for major adverse cardiovascular events.

MATERIALS AND METHODS

The retrospective analysis was based on data recorded in a single-center registry, including all carotid endarterectomies performed between 2010 and 2017. A univariate analysis was used to identify the risk factors for perioperative mortality, and predictors of stroke were determined using a multivariate logistic regression model.

RESULTS

Data from 1,832 patients with a mean age of 64.1 ± 7.6 years were analyzed. The combined in-hospital mortality was 0.65% (12/1,832). The rate of stroke was 0.7% (13/1,832), and the rate of myocardial infarction was 1.1% (20/1,832). The 30-day stroke-free survival was 99%. A history of stroke (p = 0.02) and chronic obstructive pulmonary disease (COPD; p = 0.0001) were found to be predictive of a lethal stroke. Previous myocardial infarction (p = 0.0001), an advanced stage of congestive heart failure (p = 0.0001), and angina pectoris (p = 0.01) were associated with cardiac-related mortality. Moreover, diabetes mellitus (p = 0.03), COPD (p = 0.0001), and carotid calcinosis (p = 0.006) increased the risk of poor survival due to myocardial infarction. The mean duration of clamping was found to be an independent predictor of any perioperative stroke (OR = 1.109; 95% CI 1.052-1.129; p < 0.0001).

CONCLUSIONS

The present retrospective analysis of the local carotid surgery register showed appropriate outcomes after CEA regarding the cumulative incidence of MACE, which is comparable to previously published international register data. A previous history of stroke, myocardial infarction, COPD, a prolonged clamping time during CEA, and diabetes mellitus were found to be factors of high-risk for cardiovascular mortality. A prolonged clamping was identified as an independent predictor of any stroke.

Evolution of surgical treatment of carotid artery stenosis: a single center observational study

Background: In 2009 and 2011 respectively ESVS and AHA/ASA guidelines recommended to operate patients with a symptomatic carotid artery stenosis within 14 days. This study aimed primarily to determine if an academic hospital has implemented these international guidelines about indication and timing of surgical treatment of carotid stenosis. Second, the influence of referral from another hospital on time from symptoms to surgery and the influence of time between neurological event and surgery on 30-day complication rate was studied. Third, the number of asymptomatic carotid artery lesions treated surgically was also evaluated in both periods.Methods: Retrospective study to compare patients with significant atherosclerotic carotid stenosis who underwent carotid endarterectomy (CEA) or carotid artery stenting (CAS) in 2005-2006 versus patients treated in 2014-2016. Demographic data, treatment characteristics, interval between symptom and surgery and 30-day outcomes were collected.Results: In 2005-2006 38.1% (59/155) of the patients were treated for symptomatic carotid artery stenosis, in 2014-2016 this increased to 66.5% (121/182) (p < .001, 95% CI: 0.179-0.383). Median time from neurological symptom to surgery in symptomatic patients decreased from 30 to 13 d (p <.001, 95% CI: 1.476-2.763). Early surgery did not increase the 30-day postoperative complications (p = .19, 95% CI: 0.987-1.003). Referral from another hospital almost doubled the time interval between symptoms and surgery in 2014-2016 (p <.001, 95% CI: 1.386-2.827).Conclusions: Since the publication of the international guidelines, patients with symptomatic carotid artery stenosis were preferably surgically treated within 2 weeks at an academic institution. The number of treated asymptomatic carotid stenoses was drastically reduced.

The Dutch Audit of Carotid Interventions: Transparency in Quality of Carotid Endarterectomy in Symptomatic Patients in the Netherlands

BACKGROUND

The Dutch Audit for Carotid Interventions (DACI) registers all patients undergoing interventions for carotid artery stenosis in the Netherlands. This study describes the design of the DACI and results of patients with a symptomatic stenosis undergoing carotid endarterectomy (CEA). It aimed to evaluate variation between hospitals in process of care and (adjusted) outcomes, as well as predictors of major stroke/death after CEA.

METHODS

All patients with a symptomatic stenosis, who underwent CEA and were registered in the DACI between 2014 and 2016 were included in this cohort. Descriptive analyses of patient characteristics, process of care, and outcomes were performed. Casemix adjusted hospital procedural outcomes as (30 day/in hospital) mortality, stroke/death, and major stroke/death, were compared with the national mean. A multivariable logistic regression model (backward elimination at p > 0.10) was used to identify predictors of major stroke/death.

RESULTS

A total of 6459 patients, registered by 52 hospitals, were included. The majority (4,832, 75%) were treated <2 weeks after their first hospital consultation, varying from 40% to 93% between hospitals. Mortality, stroke/death, and major stroke/death were, respectively, 1.1%, 3.6%, and 1.8%. Adjusted major stroke/death rates for hospital comparison varied between 0 and 6.5%. Nine hospitals performed significantly better, none performed significantly worse. Predictors of major stroke/death were sex, age, pulmonary disease, presenting neurological symptoms, and peri-operative shunt.

CONCLUSION

CEA in The Netherlands is associated with an overall low mortality and (major) stroke/death rate. Whereas the indicator time to intervention varied between hospitals, mortality and (major) stroke/death were not significantly distinctive enough to identify worse practices and therefore were unsuitable for hospital comparison in the Dutch setting. Additionally, predictors of major stroke/death at population level could be identified.

Surgical and Endovascular Treatment of Extracranial Carotid Stenosis

BACKGROUND

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) can be used to prevent stroke due to arteriosclerotic lesions of the carotid artery. In Germany, legally mandated quality assurance (QA) enables the evaluation of outcome quality after CEA and CAS performed under routine conditions.

METHODS

We analyzed data on all elective CEA and CAS procedures performed over the periods 2009-2014 and 2012-2014, respectively. The endpoints of the study were the combined in-hospital stroke and death rate, stroke rate and mortality separately, local complications, and other complications. We analyzed the raw data with descriptive statistics and carried out a risk-adjusted analysis of the association of clinically unalterable variables with the risk of stroke and death. All analyses were performed separately for CEA and CAS.

RESULTS

Data were analyzed from 142 074 CEA procedures (67.8% of them in men) and 13 086 CAS procedures (69.7% in men). The median age was 72 years (CEA) and 71 years (CAS). The periprocedural rate of stroke and death after CEA was 1.4% for asymptomatic and 2.5% for symptomatic stenoses; the corresponding rates for CAS were 1.7% and 3.7%. Variables associated with increased risk included older age, higher ASA class (ASA = American Society of Anesthesiologists), symptomatic vs. asymptomatic stenosis, 50-69% stenosis, and contralateral carotid occlusion (for CEA only).

CONCLUSION

These data reveal a low periprocedural rate of stroke or death for both CEA and CAS. This study does however not permit any conclusions as to the superiority or inferiority of CEA and CAS.

Regional variation in patient selection and treatment for lower extremity vascular disease in the Vascular Quality Initiative

OBJECTIVE

Prior studies on the cause and effect of surgical variation have been limited by utilization of administrative data. The Vascular Quality Initiative (VQI), a robust national clinical registry, provides anatomic and perioperative details allowing a more robust analysis of variation in surgical practice.

METHODS

The VQI was used to identify all patients undergoing infrainguinal open bypass or endovascular intervention from 2009 to 2014. Asymptomatic patients were excluded. The 16 regional groups of the VQI were used to compare variation in patient selection, operative indication, technical approach, and process measures. χ² analysis was used to assess for differences across regions where appropriate.

RESULTS

A total of 52,373 interventions were included (31%). Of the 16,145 bypasses, 5% were performed for asymptomatic disease, 26% for claudication, 56% for chronic limb-threatening ischemia (CLI) (61% of these for tissue loss), and 13% for acute limb-threatening ischemia. Of the 35,338 endovascular procedures, 4% were for asymptomatic disease, 40% for claudication, 46% for CLI (73% tissue loss), and 12% for acute limb-threatening ischemia. Potentially unwarranted variation included proportion of prosthetic conduit for infrapopliteal bypass in claudication (13%-41%, median, 29%; P < .001), isolated tibial endovascular intervention for claudication (0.0%-5.0%, median, 3.0%; P < .001), discharge on antiplatelet and statin (bypass: 62%-84%; P < .001; endovascular: 63%-89%; P < .001), and ultrasound guidance for percutaneous access (claudication: range, 7%-60%; P < .001; CLI: 5%-65%; P < .001). Notable areas needing further research with significant variation include proportion of CLI vs claudication treated by bypass (38%-71%; P < .001) and endovascular intervention (28%-63%; P < .001), and use of closure devices in percutaneous access (claudication; 26%-76%; P < .001; CLI: 30%-78%; P < .001).

CONCLUSIONS

Significant variation exists both in areas where evidence exists for best practice and, therefore, potentially unwarranted variation, and in areas of clinical ambiguity. Quality improvement efforts should be focused on reducing unwarranted variation. Further research should be directed at identifying best practice where no established guidelines and high variation exists.

Vascular interventions in the elderly

Overused?

Elevated levels of endothelial-derived microparticles, and serum CXCL9 and SCGF-β are associated with unstable asymptomatic carotid plaques

Endothelial microparticles (EMPs) are released from dysfunctional endothelial cells. We hypothesised that patients with unstable carotid plaque have higher levels of circulating microparticles compared to patients with stable plaques, and may correlate with serum markers of plaque instability and inflammation. Circulating EMPs, platelet MPs (PMPs) and inflammatory markers were measured in healthy controls and patients undergoing carotid endarterectomy. EMP/PMPs were quantified using flow cytometry. Bioplex assays profiled systemic inflammatory and bone-related proteins. Immunohistological analysis detailed the contribution of differentially-regulated systemic markers to plaque pathology. Alizarin red staining showed calcification. EMPs and PMPs were significantly higher in patients with carotid stenosis (≥70%) compared to controls, with no differences between asymptomatic vs symptomatic patients. Asymptomatic patients with unstable plaques exhibited higher levels of EMPs, CXCL9 and SCGF-β compared to those with stable plaques. CXCL9, and SCGF-β were detected within all plaques, suggesting a contribution to both localised and systemic inflammation. Osteopontin and osteoprotegerin were significantly elevated in the symptomatic vs asymptomatic group, while osteocalcin was higher in asymptomatic patients with stable plaque. All plaques exhibited calcification, which was significantly greater in asymptomatic patients. This may impact on plaque stability. These data could be important in identifying patients at most benefit from intervention.

Risk Factors For Stroke, Myocardial Infarction, or Death Following Carotid Endarterectomy: Results From the International Carotid Stenting Study

OBJECTIVES

Carotid endarterectomy (CEA) is standard treatment for symptomatic carotid artery stenosis but carries a risk of stroke, myocardial infarction (MI), or death. This study investigated risk factors for these procedural complications occurring within 30 days of endarterectomy in the International Carotid Stenting Study (ICSS).

METHODS

Patients with recently symptomatic carotid stenosis >50% were randomly allocated to endarterectomy or stenting. Analysis is reported of patients in ICSS assigned to endarterectomy and limited to those in whom CEA was initiated. The occurrence of stroke, MI, or death within 30 days of the procedure was reported by investigators and adjudicated. Demographic and technical risk factors for these complications were analysed sequentially in a binomial regression analysis and subsequently in a multivariable model.

RESULTS

Eight-hundred and twenty-one patients were included in the analysis. The risk of stroke, MI, or death within 30 days of CEA was 4.0%. The risk was higher in female patients (risk ratio [RR] 1.98, 95% CI 1.02-3.87, p = .05) and with increasing baseline diastolic blood pressure (dBP) (RR 1.30 per +10 mmHg, 95% CI 1.02-1.66, p = .04). Mean baseline dBP, obtained at the time of randomization in the trial, was 78 mmHg (SD 13 mmHg). In a multivariable model, only dBP remained a significant predictor. The risk was not related to the type of surgical reconstruction, anaesthetic technique, or perioperative medication regimen. Patients undergoing CEA stayed a median of 4 days before discharge, and 21.2% of events occurred on or after the day of discharge.

CONCLUSIONS

Increasing diastolic blood pressure was the only independent risk factor for stroke, MI, or death following CEA. Cautious attention to blood pressure control following symptoms attributable to carotid stenosis could reduce the risks associated with subsequent CEA.

Impact of risk scoring on decision-making in symptomatic moderate carotid atherosclerosis

Background

Benefit from carotid endarterectomy (CEA) in symptomatic moderate (50–69 per cent) carotid stenosis remains marginal. The Fourth National Clinical Guideline for Stroke recommends use of the risk score from the European Carotid Surgery Trial (ECST) to aid decision-making in symptomatic carotid disease. It is not known whether clinicians are, in fact, influenced by it.

Methods

Using the ECST risk prediction model, three scenarios of patients with a low (less than 10 per cent), moderate (20–25 per cent) and high (40–45 per cent) 5-year risk of stroke were devised and validated. Invitations to complete an online survey were sent by e-mail to vascular surgeons and stroke physicians, with responses gathered. The questionnaire was then repeated with the addition of the ECST risk score.

Results

Two hundred and one completed surveys were analysed (21·5 per cent response rate): 107 by stroke physicians and 94 by vascular surgeons. The high-risk scenario after the introduction of the ECST risk score showed an increased use of CEA (66·7 versus 80·1 per cent; P = 0·009). The low-risk scenario after risk score analysis demonstrated a swing towards best medical therapy (23·4 versus 57·2 per cent; P &lt; 0·001). CEA was preferred in the moderate-risk scenario and this was not altered significantly by introduction of the risk score (71·6 versus 75·6 per cent; P = 0·609). Vascular surgeons exhibited a preference towards CEA compared with stroke physicians in both low- and moderate-risk scenarios (P &lt; 0·001 and P = 0·003 respectively).

Conclusion

The addition of a risk score appeared to influence clinicians in their decision-making towards CEA in high-risk patients and towards best medical therapy in low-risk patients.

Mandibular subluxation as an adjunct in very distal carotid arterial reconstruction: incidence of peripheral and cerebral neurologic sequelae in a single-center experience

BACKGROUND

The location of the carotid bifurcation and a very distal extension of internal carotid atherosclerotic disease may challenge vascular surgeons performing carotid endarterectomy (CEA) by increasing technical difficulty and possibly the incidence of cranial nerve damage or palsies. The objective of the present study is to report on the safety of CEA with mandibular subluxation (MS) and to compare results of CEA in 2 groups of patients treated by standard CEA or by MS-CEA according to rates of major neurologic complications, death, and the occurrence of postoperative peripheral nerve palsy.

METHODS

Between July 2000 and June 2012, 1,357 CEAs were performed. MS was additionally used in 43 patients. Only patients with primary atherosclerotic internal carotid artery (ICA) lesions in the 2 groups (38 in the MS-CEA group and 1,289 in the standard CEA group) were considered for comparative analysis.

RESULTS

MS-CEA patients were more frequently male (P = 0.03), presented more frequently with symptomatic lesions (P = 0.007), longer lesions (P = 0.01), and had common ICA bypass implantation (P = 0.02). Mean follow-up was 68.75 ± 37.87 months (range: 1-144 months). No perioperative neurologic mortality and no prolonged discomfort related to MS was recorded. The overall neurologic morbidity rate (major stroke/minor stroke/transient ischemic attach) was comparable in the 2 groups (P = 0.78). The overall immediate peripheral nerve injury rate was 7.89% in the MS-CEA group and 5.27% in the standard CEA group (P = 0.73). Three cases of permanent dysphonia in the standard CEA group (0.23%) and 1 case of dysphagia in the MS-CEA group (2.63%) were reported at follow-up (P = 0.24).

CONCLUSIONS

MS-CEA can be a very useful technical adjunct for high-located carotid bifurcations or challenging carotid lesions, with an overall risk comparable to that of standard CEA.

Strategies to reduce variation in the use of surgery

Provision rates for surgery vary widely in relation to identifiable need, suggesting that reduction of this variation might be appropriate. The definition of unwarranted variation is difficult because the boundaries of acceptable practice are wide, and information about patient preference is lacking. Very little direct research evidence exists on the modification of variations in surgery rates, so inferences must be drawn from research on the alteration of overall rates. The available evidence has large gaps, which suggests that some proposed strategies produce only marginal change. Micro-level interventions target decision making that affects individuals, whereas macro-level interventions target health-care systems with the use of financial, regulatory, or incentivisation strategies. Financial and regulatory changes can have major effects on provision rates, but these effects are often complex and can include unintended adverse effects. The net effects of micro-level strategies (such as improvement of evidence and dissemination of evidence, and support for shared decision making) can be smaller, but better directed. Further research is needed to identify what level of variation in surgery rates is appropriate in a specific context, and how variation can be reduced where desirable.

Modelling the cost-effectiveness of carotid endarterectomy for asymptomatic stenosis5

Background

The aim of this study was to model the cost-effectiveness of carotid endarterectomy for asymptomatic stenosis versus medical therapy based on 10-year data from the Asymptomatic Carotid Surgery Trial (ACST).

Methods

This was a cost–utility analysis based on clinical effectiveness data from the ACST with UK-specific costs and stroke outcomes. A Markov model was used to calculate the incremental cost-effectiveness ratio (ICER, or cost per additional quality-of-life year) for a strategy of early endarterectomy versus medical therapy for the average patient and published subgroups. An exploratory analysis considered contemporary event rates.

Results

The ICER was £ 7584 per additional quality-adjusted life-year (QALY) for the average patient in the ACST. At thresholds of £ 20 000 and £ 30 000 there was a 74 and 84 per cent chance respectively of early endarterectomy being cost-effective. The ICER for men below 75 years of age was £ 3254, and that for men aged 75 years or above was £ 71 699. For women aged under 75 years endarterectomy was less costly and more effective than medical therapy; for women aged 75 years or more endarterectomy was less effective and more costly than medical therapy. At contemporary perioperative event rates of 2·7 per cent and background any-territory stroke rates of 1·6 per cent, early endarterectomy remained cost-effective.

Conclusion

In the ACST, early endarterectomy was predicted to be cost-effective in those below 75 years of age, using a threshold of £ 20 000 per QALY. If background any-territory stroke rates fell below 1 per cent per annum, early endarterectomy would cease to be cost-effective.