Increased Anterior Abdominal Aortic Wall Motion: Possible Role in Aneurysm Pathogenesis and Design of Endovascular Devices

Purpose:To determine whether variations in aortic wall motion exist in mammalian species other than humans and to consider the potential implications of such variations.Methods:M-mode ultrasound was used to measure abdominal aortic wall motion in 4 animal species [mice (n=10), rats (n=8), rabbits (n=7), and pigs (n=5)], and humans (n=6). Anterior wall displacement, posterior wall displacement, and diastolic diameter were measured. The ratio of displacement to diameter and cyclic strain were calculated.Results:Body mass varied from 24.1±2.4 g (mouse) to 61.8±13.4 kg (human); aortic diameter varied from 0.53±0.07 mm (mouse) to 1.2±1 mm (human). Anterior wall displacement was 2.5 to 4.0 times greater than posterior among the species studied. The ratios of wall displacement to diastolic diameter were similar for the anterior (range 9.40%–11.80%) and posterior (range 2.49%–3.91%) walls among species. The ratio of anterior to posterior displacement (range 2.47–4.03) and aortic wall circumferential cyclic strain...