137 - WSS and velocity changes of common iliac arteries in patients with abdominal aortic aneurysm: assessment using 4D flow MRI.

One under-investigated area of abdominal aortic aneurysm (AAA) research is how changes in iliac arteries flow alter infrarenal aortic hemodynamics and aneurysm expansion. Therefore, the aim of this study was to investigate the hemodynamics of iliac arteries in healthy volunteers and AAA patients, further exploring the occurrence of auxiliary aneurysm. Healthy volunteers and patients with abdominal aortic aneurysm were continuously included, and patients with other aortic diseases were excluded. All the subjects underwent MRI on a 3.0T MR scanner, and hemodynamic parameters, including total flow volume, peak velocity and wall shear stress (WSS) of left common iliac artery (LCIA) and right common iliac artery (RCIA) were recorded. Between December 2022 and May 2023, 16 volunteers (54.89±14.55 years) and 22 AAA patients (68.73±13.77 years) were included. There was no significant difference in flow volume between controls and AAA both in LCIA and RCIA. However, the WSS decreased in AAA patients both in LCIA (0.61±0.19 vs. 0.34±0.11, P =0.014) and RCIA (0.57±0.19 vs. 0.32±0.18, P =0.025). In healthy volunteers, there was good consistency of hemodynamic parameters between the left and right iliac artery. However, peak velocity between left and right common iliac arteries is significantly different in AAA (78.57±22.76 vs. 58.31±16.66, P =0.025). In this study, 4D flow MRI were used to evaluate the iliac arteries dynamics changes between healthy controls and AAA patients. In AAA patients, the WSS of both left and right iliac arteries was decreased, and the hemodynamic parameters between the left and right iliac arteries are asymmetrical. These changes are of great value for predicting the development of abdominal aortic aneurysms and even for predicting the occurrence and development of iliac aneurysms. [ABSTRACT FROM AUTHOR]