The WARRIORS Trial United States

Women with aortic aneurysms have been treated using guidelines historically developed from research on men. This trial seeks to fine tune the approach for women.

The WARRIORS Trial is a landmark clinical study dedicated to finding a better, evidence-based standard of care for women — one built around their biology.

Abdominal aortic aneurysms (AAAs) are a serious and often silent vascular condition. Although women develop AAAs less frequently than men, they face higher complication rates, are more likely to rupture at smaller aneurysm sizes, and have significantly worse outcomes when rupture occurs.

Yet the clinical guidelines used to decide when to operate were developed almost entirely from research on men, leaving a critical evidence gap for women.

The WARRIORS Trial was created to close that gap. By focusing exclusively on women with small AAAs, this international study aims to determine whether earlier treatment can reduce rupture risk, improve survival, and make quality of life better for women worldwide.

What We’re Studying

WARRIORS compares two approaches to managing small AAA (4.0–5.4 cm) in women:

  • Early Endovascular Aneurysm Repair (Early EVAR): A minimally invasive procedure performed while the aneurysm is still small
  • Routine surveillance: Regular monitoring with repair offered if the aneurysm reaches 5.5 cm or larger. (Current treatment standard)

Participants are followed for five years, tracking survival, rupture rates, quality of life, and costs. The findings will directly inform future clinical guidelines for women with AAA.

Funding & Leadership

The U.S. arm of WARRIORS is funded by the National Institutes of Health (NIH) — National Heart, Lung, and Blood Institute. Stanford University serves as the Clinical Coordinating Center (PI: Dr. Shipra Arya). The University of Alabama at Birmingham serves as the Data Coordinating Center (PIs: Dr. Jeff Szychowski, Dr. Adam Beck). The trial is conducted in partnership with Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) and is overseen by the Imperial College London International Clinical Trial Coordinating Center.