Early Endovascular Repair Versus Surveillance for Women With Small Abdominal Aortic Aneurysm

Elective Abdominal Aortic Aneurysm (AAA) repair is offered when the risk of rupture exceeds the risk of surgery. Women (versus men) have a four-fold higher risk of AAA rupture but almost double the operative mortality. It is unknown whether the current 5.5cm diameter AAA repair threshold, derived from randomised trials including only 4% women, is applicable to women.

Therefore, should women have their aneurysms repaired electively at smaller diameters than men to improve their AAA-related survival and quality of life? WARRIORS is an international randomised controlled trial of early elective endovascular repair versus routine surveillance in women (n=1112) with small asymptomatic AAA (4-5.4cm diameter), nested within a registry of non-participants. The surveillance group will be offered repair for rupture or upon reaching the 5.5cm threshold. Randomisation will be 1:1 stratified by country, age, and aneurysm diameter. The trial is powered for aneurysm-related mortality or rupture at 5 years. Quality-Adjusted-Life-Years is a major secondary outcome. Other outcomes include: operative mortality and complications, anxiety, major cardiovascular adverse events, and cost-effectiveness. Quality-of-life and anxiety questionnaires and "standard-of-care" using routine data will be collected.

The trial aims to progress health equity through provision of evidence for sex-specific clinical guidelines for AAA repair.