A prospective observational cohort study to assess the eligibility, uptake, viability, acceptability, safety, and cost of a ShorT stay (23-hour) Aneurysm Repair (STAR) pathway. Outcomes will be collected for up to 1 year.

The STAR study is a prospective multicentre observational cohort study to assess the eligibility, uptake, viability, acceptability, safety, and cost of a short stay (23-hour) aneurysm pathway for infrarenal AAA patients.

The study will take place at least at five sites in the United Kingdom. Over a 12-month recruitment period, all patients with AAA referred to or diagnosed at each of the units will be assessed for inclusion in the STAR pathway if suitable for EVAR. The study anticipates the assessment of over 200 AAA patients with the aim of recruiting up to 100 patients into the study to undergo EVAR using the STAR pathway.

Patients may be enrolled into the study to undergo EVAR using the STAR pathway provided all inclusion and no exclusion criteria are met. Subjects will be evaluated through to hospital discharge, receive a telephone call at 48 hours, return for follow-up visits at one month, and telephone follow-ups at three- and six months post treatment. Patients recruited into the study will have their routine clinical data collected at 12 months when they return for follow-up visits.

Inclusion Criteria:

• They have been assessed as suitable for standard infrarenal EVAR within the manufacturer's "Instructions for Use" for the chosen endograft.
• Age over 55 (effectively excluding connective tissue disease)
• Fully independent at home or adequate provision for home care after discharge which would enable patients to perform basic activities of daily living including mobility, eating, drinking, and bathing
• Living with a partner or family member or having similar help available for the first 24-hours after discharge from the hospital
• Transport to attend the hospital in which they were treated within 1 hour for the first 24-hours after discharge. Should an ambulance not be readily available to attend the hospital within this timeframe, patients must be made aware and agree to make their own transport arrangements.
• Capable of complying with Protocol requirements, including follow-up
• An Informed Consent Form signed by the participant or legal representative

Exclusion Criteria:

• Significant cardiac disease, defined as one or more major predictors of increased perioperative cardiovascular risk according to the American College of Cardiology Cardiac Risk Classification, which remains untreated at the time of surgery
• Significant renal failure (pre-operative creatinine level of over 150 μmol/L or GFR less than 30mL/min/1.73m2 indicating severe chronic kidney disease (stage IV)
• Significant respiratory disease needing increased post-operative care not available in the home environment (e.g., nebulisers or oxygen therapy which is not set up at home)
• Any other condition, which in the opinion of the multidisciplinary team makes discharge within 23-hours unsafe
• Patients who lack capacity to consent to 23-hour EVAR will be excluded from the study
• There is concurrent enrolment in another drug or medical device study or have recently been involved in any research prior to recruitment

All patients with an infrarenal abdominal aortic aneurysm in at least five sites will be assessed for inclusion into the study. This is expected to be over 200 patients in five high-volume sites. From these patients, suitable patients will be able to be enrolled in the STAR pathway. The investigators expect approximately 100 patients to be enrolled from five UK centres.