Clinical Response to Procedural Stroke Following Carotid Endarterectomy: A Delphi Consensus Study.

OBJECTIVE: No dedicated studies have been performed on the optimal management of patients with an acute stroke related to carotid intervention nor is there a solid recommendation given in the European Society for Vascular Surgery guideline. By implementation of an international expert Delphi panel, this study aimed to obtain expert consensus on the optimal management of in hospital stroke occurring during or following CEA and to provide a practical treatment decision tree. METHODS: A four round Delphi consensus study was performed including 31 experts. The aim of the first round was to investigate whether the conceptual model indicating the traditional division between intra- and post-procedural stroke in six phases was appropriate, and to identify relevant clinical responses during these six phases. In rounds 2, 3, and 4, the aim was to obtain consensus on the optimal response to stroke in each predefined setting. Consensus was reached in rounds 1, 3, and 4 when ≥ 70% of experts agreed on the preferred clinical response and in round 2 based on a Likert scale when a median of 7 - 9 (most adequate response) was given, IQR ≤ 2. RESULTS: The experts agreed (> 80%) on the use of the conceptual model. Stroke laterality and type of anaesthesia were included in the treatment algorithm. Consensus was reached in 17 of 21 scenarios (> 80%). Perform diagnostics first for a contralateral stroke in any phase, and for an ipsilateral stroke during cross clamping, or apparent stroke after leaving the operation room. For an ipsilateral stroke during the wake up phase, no formal consensus was achieved, but 65% of the experts would perform diagnostics first. A CT brain combined with a CTA or duplex ultrasound of the carotid arteries should be performed. For an ipsilateral intra-operative stroke after flow restoration, the carotid artery should be re-explored immediately (75%). CONCLUSION: In patients having a stroke following carotid endarterectomy, expedited diagnostics should be performed initially in most phases. In patients who experience an ipsilateral intra-operative stroke following carotid clamp release, immediate re-exploration of the index carotid artery is recommended.

A Clinical Validation Study of Anatomical Risk Scoring for Procedural Stroke in Patients Treated by Carotid Artery Stenting in the International Carotid Stenting Study.

OBJECTIVES: Vascular anatomy of the aortic arch and supra-aortic arteries has been suggested as influencing the risk of carotid artery stenting (CAS). The expert opinion based Delphi anatomical risk (DAR) score was developed to predict difficulty of CAS in relation to procedural stroke risk, and thereby aid patient selection. The aim was to validate the DAR score in the context of a randomised clinical trial. METHODS: In this post hoc analysis of the International Carotid Stenting Study (ICSS), only patients treated by CAS with available pre-procedural CT angiography (CTA) were included. Patients with tortuous anatomy unsuitable for stenting were excluded from ICSS. CTA based vascular anatomy was rated by two independent observers. Every possible combination of anatomy resulted in a risk score, divided in four categories of expected risk (low, < 5.0; low-intermediate, 5.0-5.9; high-intermediate, 6.0-6.9; high, ≥ 7.0). Binomial logistic regression was used to assess the relationship between anatomical risk score and procedural risk of any stroke. Differences between predefined age groups were also assessed. RESULTS: A total of 275 patients were included. Interobserver reliability for all anatomical risk factors was high (κ = 0.76-0.84). In total, 16 strokes (6%) occurred in the procedural period. No significant relationship was observed between the DAR score and risk of procedural stroke, with the risk of stroke being 9% in the high risk vs. 4% in the low risk categories (p = .49). A higher mean DAR score was observed in patients ≥70 years compared with younger patients (4.6 ± 1.5 vs. 3.9 ± 1.4, p < .001), which was mainly explained by higher rates of arch atheroma (44% vs. 20%, p < .001). Prolonged intervention duration was significantly associated with increased stroke risk (11% vs. 4%, p < .04), but not with the DAR score. CONCLUSIONS: No statistically significant association was found between anatomical difficulty, as defined in the DAR score, and procedural stroke risk. However, the small sample size potentially rendered the study underpowered to detect group differences, and confirmation with a larger sample is essential.

Carotid endarterectomy has significantly lower risk in the last two decades: should the guidelines now be updated?

Carotid endarterectomy (CEA) carries a significant risk of procedural stroke and death Guidelines recommend keeping this risk below 6% and below 3% for symptomatic and asymptomatic patients respectively. After analyzing our Institute's CEA results during the past 25 years, we found the rate of postoperative complications was now well below Guideline thresholds. Accordingly, we studied temporal changes in procedural risks in randomized controlled trials (RCTs) and in large observational studies in order to compare these against Guidelines. We found a clear temporal trend towards improving procedural outcomes, which can be explained by improvements in medical therapy, more appropriate timing of CEA, the use of local anesthesia and the use of peroperative cerebral monitoring as well as improving surgical techniques. An update of current guidelines should now be undertaken, since our findings are not unique and are supported by other studies in this review.

Asymptomatic carotid artery stenosis: who should be screened, who should be treated and how should we treat them?

Although stopping smoking, lowering blood pressure and reducing lipid levels will reduce global stroke risk and cardiovascular mortality, these remain leading causes of death and disability especially in ageing populations. Further prevention strategies are needed and, in the first part of this review, we explore the potential benefits of appropriate screening for carotid artery disease to reduce stroke and identify those who may have related cardiac disease. Although whole-population carotid screening is an inefficient and costly means of identifying candidates with tight carotid stenosis who might warrant intervention, it can identify many people with lower levels of stenosis who may benefit from cardiovascular risk-reducing medications. Longer-term benefits and cost-effectiveness of any targeted screening program needs further evaluation. Patients with carotid stenosis are known to be at increased risk of stroke and vascular death. Whilst randomized clinical trials and guidelines have reported stroke hazards and benefits of interventional treatment for carotid stenosis, uncertainty remains about their optimal medical management. In the second part of this review we discuss Level I evidence for medical and surgical treatment of asymptomatic carotid stenosis, reasons for the current lack of consensus on interventional management of these patients and future studies which may help to clarify which groups will (and which will likely not) benefit from interventions.

Clinical Experience amongst Surgeons in the Asymptomatic Carotid Surgery Trial-1.

INTRODUCTION: Hospital volume may influence the outcomes of carotid revascularization, but in trials the effect of the clinical experience of individual surgeons on procedural outcome is less certain. We assessed perioperative event rates amongst centers with different trial entry volumes and also the effects of individual operator experience in the first Asymptomatic Carotid Surgery Trial-1 (ACST-1). METHODS: In 126 centers participating in ACST-1, surgeons were classified according to their in-trial experience (group A: 50 cases; group B: 51-100 cases; group C: >100 cases), center enrolment volume (group I: <30 patients; group II: 30-75 patients; group III: >75 patients) and center annual hospital volume (group 1: <40 carotid endarterectomies (CEAs); group 2: 40-75 CEAs; group 3: >75 cases). Differences in perioperative event rates were compared using logistic regression analysis. RESULTS: In centers with the most clinical experience compared with those with least experience (groups C vs. A), the number of strokes or deaths was 8 of 275 (2.9%) versus 24 of 810 (3.0%) with OR 0.99 (95% CI 0.44-2.25, p = 0.986). Numbers of strokes or death in high enrolment centers compared with those in low enrolment centers (groups III vs. I) was 20 of 680 (2.9%) versus 21 of 580 (3.6%) with OR 0.81 (95% CI 0.43-1.51, p = 0.921). In centers with a high annual volume compared with those of low annual volume (groups 3 vs. 1), numbers of strokes and death were non-significantly lower, 26 of 823 (3.2%) versus 19 of 422 (4.5%) with OR 0.68 (95% CI 0.37-1.26, p = 0.386). Cumulative stroke risk at 5 and 10 years were similar among different levels of reported clinical experience, enrolment volume and annual hospital volume. CONCLUSION: Although our data did not demonstrate an association between perioperative complications and operators' experience, enrolment volume or annual hospital volume, rates of stroke or death were numerically lower in both high enrolment and high annual volume centers. This lack of association could be explained by an overall low procedural risk in ACST-1.