Factors associated with delay to carotid endarterectomy for acute ischaemic stroke in South Australia: A multicentre retrospective cohort study.

Background: The greatest benefits of carotid endarterectomy (CEA) accrue when performed within two weeks of acute ischaemic stroke (AIS) due to symptomatic carotid stenosis. Previous studies have identified multiple factors contributing to CEA delay.

Aims: To determine factors associated with delayed CEA in patients admitted to tertiary stroke centres within a major metropolitan region with AIS METHODS: In a retrospective cohort study, consecutive patients admitted to the tertiary hospitals with stroke units within South Australia (Lyell McEwin Hospital, Royal Adelaide Hospital and Flinders Medical Centre) between 2016 to 2020 were included. Univariable and multivariable logistic regression were used to identify individual factors associated with time from symptom onset to CEA of over two weeks.

Results: A total of 174 patients were included. The median time to CEA was 5 days (IQR 3-9.75). Delayed CEA beyond 14 days occurred in 28/174 (16%). Factors most associated with delayed CEA included presentation to a tertiary hospital without onsite Vascular Surgical Unit (OR 3.71, 95%CI 1.31-10.58), history of previous stroke (OR 3.38, 95% CI 1.11-9.84) and presenting NIHSS above 6 (OR 5.16, 95% CI 1.60-16.39).

Conclusion: This study identified that presentation to a tertiary hospital without a Vascular Surgery Unit, history of previous stroke and presenting NIHSS above 6 were associated with delay to CEA in AIS patients in South Australia. Interventional studies aiming to improve the proportion of patients that receive CEA within 14 days are required.