A Decade of Centralisation of Vascular Services in the UK

The Diagnostic Value of Biomarkers in Acute Mesenteric Ischaemia Is Insufficiently Substantiated: A Systematic Review

OBJECTIVE

There is an urgent need for accurate biomarkers to support timely diagnosis of acute mesenteric ischaemia (AMI) and thereby improve clinical outcomes. With this systematic review, the aim was to substantiate the potential diagnostic value of biomarkers for arterial occlusive AMI.

DATA SOURCES

The Pubmed, Embase, and the Cochrane Library electronic databases were searched.

REVIEW METHODS

A systematic review of the literature has been conducted to define the potential diagnostic value of biomarkers for arterial occlusive AMI. All studies including ≥ 10 patients describing biomarkers for macrovascular occlusive AMI between 1950 and 17 February 2023 were identified within the Pubmed, Embase, and the Cochrane Library electronic databases. There were no restrictions to any particular study design, but letters and editorials were excluded. The QUADAS-2 tool was used for the critical appraisal of quality. The study protocol was registered on Prospero (CRD42021254970).

RESULTS

Fifty of 4334 studies were eligible for inclusion in this review. Ninety per cent of studies were of low quality. A total of 60 biomarkers were identified, with 24 in two or more studies and 15 in five or more studies. There was variation in reported units, normal range, and cut off values. Meta-analysis was not possible due to study heterogeneity. Biomarkers currently recommended by the European Journal of Vascular and Endovascular Surgery, European Society for Trauma and Emergency Surgery 2016, and World Society of Emergency Surgery 2017 guidelines also had heterogeneous low quality data for use in the diagnosis of AMI.

CONCLUSION

This systematic review demonstrates high heterogeneity and low quality of the available evidence on biomarkers for arterial occlusive AMI. No clinical conclusions can be drawn on a biomarker or combination of biomarkers for patients suspected of arterial occlusive AMI. Restraint is advised when rejecting or determining AMI solely based on biomarkers.

Impact of Vascular Service Centralization on the Carotid Endarterectomy Pathway: A Study at the Bedfordshire, Luton, and Milton Keynes Vascular Network

Introduction Carotid endarterectomy (CEA) is the gold standard intervention for patients experiencing transient ischemic attacks (TIAs) or embolic strokes with >50% internal carotid artery (ICA) stenosis supplying index hemispheric territory. The recommended period for CEA is 14 days post-index event; this period carries a heightened risk for second ischemic events. However, implementation of this stringent timeline often encounters delays stemming from multifaceted factors. The centralization of vascular services, designed to enhance patient care, introduces a paradigm shift. Centralization's efficacy in improving patient outcomes, particularly in the CEA pathway, is a subject of ongoing investigation. Our study aims to discern the impact of centralized services on the timeliness of CEA for symptomatic carotid artery stenosis, shedding light on this complex interplay of factors. Methods This retrospective study analyzed CEA data at the Bedfordshire, Luton, and Milton Keynes Vascular Network between January 2021 and June 2023. Eligible patients exhibited symptomatic carotid artery stenosis, with asymptomatic cases; those unfit for surgery or receiving best medical therapy only were excluded. Patients were categorized by their primary referral location: Hub, Spoke-1, or Spoke-2. Demographic and referral data were collected, and timelines from symptom onset to surgery were recorded. Continuous variables were expressed as means and standard deviations, and categorical variables as counts and percentages. Box plots illustrated the relationship between referral origin and surgery timing, and the Classification and Regression Tree (CART) assessed second events. Statistical significance was determined using Fisher's exact and chi-square tests, with p<0.05 indicating significance. Results A total of 148 patients underwent CEA after implementing exclusion criteria. 35.5% (n=53) of patients were referred from the Hub, while 45.6% (n=67) and 18.8% (n=28) were from Spoke-1 and Spoke-2, respectively. 40% (n=59) received CEA within the recommended timeframe, and 15.4% (n=23) experienced a second ischemic event pre-surgery. Time from TIA clinic review to referral was 5.5±8 days and 16.4±20 days from vascular referral to surgery. Patterns of delays were observed, with Spoke-2 exhibiting the most significant delays. Notably, amaurosis fugax and embolic stroke correlated with recurrent ischemic events, emphasizing the importance of timely care in CEA. Conclusion Our study underscores the significant benefits and challenges of the Hub and Spoke model in vascular surgery. The growing referral delays from Spoke sites are concerning, emphasizing the need for a multi-disciplinary team approach within Spoke sites to ensure efficient and standardized care delivery.

Incidence and Outcomes of Abdominal Aortic Aneurysm Repair in New Zealand from 2001 to 2021

Purpose: The burden of abdominal aortic aneurysms (AAA) has changed in the last 20 years but is still considered to be a major cause of cardiovascular mortality. The introduction of endovascular aortic repair (EVAR) and improved peri-operative care has resulted in a steady improvement in both outcomes and long-term survival. The objective of this study was to identify the burden of AAA disease by analysing AAA-related hospitalisations and deaths. Methodology: All AAA-related hospitalisations in NZ from January 2001 to December 2021 were identified from the National Minimum Dataset, and mortality data were obtained from the NZ Mortality Collection dataset from January 2001 to December 2018. Data was analysed for patient characteristics including deprivation index, repair methods and 30-day outcomes. Results: From 2001 to 2021, 14,436 patients with an intact AAA were identified with a mean age of 75.1 years (SD 9.7 years), and 4100 (28%) were females. From 2001 to 2018, there were 5000 ruptured AAA with a mean age of 77.8 (SD 9.4), and 1676 (33%) were females. The rate of hospitalisations related to AAA has decreased from 43.7 per 100,000 in 2001 to 15.4 per 100,000 in 2018. There was a higher proportion of rupture AAA in patients living in more deprived areas. The use of EVAR for intact AAA repair has increased from 18.1% in 2001 to 64.3% in 2021. The proportion of octogenarians undergoing intact AAA repair has increased from 16.2% in 2001 to 28.4% in 2021. The 30-day mortality for intact AAA repair has declined from 5.8% in 2001 to 1.7% in 2021; however, it has remained unchanged for ruptured AAA repair at 31.6% across the same period. Conclusions: This study highlights that the incidence of AAA has declined in the last two decades. The mortality has improved for patients who had a planned repair. Understanding the contemporary burden of AAA is paramount to improve access to health, reduce variation in outcomes and promote surgical quality improvement.