Lower extremity amputation increases oscillatory flow in the infrarenal aorta: A new potential risk factor for abdominal aortic aneurysm development

Background Abdominal aortic aneurysms (AAA) are a major cause of morbidity and mortality in the US. The most common location of AAA is the infrarenal abdominal aorta where oscillatory flow is present over the cardiac cycle, figure 1. Oscillatory flow is known to initiate an inflammatory response in endothelial cells. Patients with lower extremity traumatic amputations have a 5-fold increase in AAA occurrence unrelated to co-morbidities. The objective of the study is to determine the amount of infrarenal aortic oscillatory flow changes between baseline and acute occlusion of arterial blood supply to a lower extremity (a condition mimicking a lower extremity amputation).