Polar orientation of renal grafts within the proximal seal zone affects risk of early type IA endoleaks after chimney endovascular aneurysm repair

Renal chimney grafts vary considerably in both starting position and their polar trajectory within the proximal seal zone. Grafts that traverse >90 degrees in polar angle within the seal zone may be at increased risk of early type IA endoleaks and require more frequent imaging surveillance. Caudally directed renal arteries result in a more favorable polar geometry (eg, cranial-caudal orientation) with respect to endoleak risk and thus are more ideal candidates for parallel graft strategies.