There are multiple definitions:

1. area ejection fraction(English)

   • EF, HFNEF, LVEF
   • Cardiology, Ratio-based metric
   • https://doi.org…93/bja/64.3.331

2. aortoenteric fistula(English)

   • defined as an abnormal connection between the aorta or its major arterial branches and the GI tract in patients with or without previous aortic surgery
   • GI, VAA
   • Anatomy, Vascular disease
   • https://doi.org…40232-3.00088-1