The vascular properties of large vessels in the obese have not been adequately studied. We used cardiovascular magnetic resonance imaging to quantify the cross-sectional area and elastic properties of the ascending thoracic and abdominal aorta in 21 clinically healthy obese young adult men and 25 men who were age-matched lean controls. Obese subjects had greater maximal cross-sectional area of the ascending thoracic aorta (984 ± 252 vs 786 ± 109 mm2, p <0.01) and of the abdominal aorta (415 ± 71 vs 374 ± 51 mm2, p <0.05). When indexed for height the differences persisted, but when indexed for body surface area, a significant difference between groups was found only for the maximal abdominal aortic cross-sectional area. The obese subjects also had decreased abdominal aortic elasticity, characterized by 24% lower compliance (0.0017 ± 0.0004 vs 0.0021 ± 0.0005 mm2/kPa/mm, p <0.01), 22% higher stiffness index β (6.0 ± 1.5 vs 4.9 ± 0.7, p <0.005), and 41% greater pressure-strain elastic modulus (72 ± 25 vs 51 ± 9, p <0.005). At the ascending thoracic aorta, only the pressure-strain elastic modulus was different between obese and lean subjects (85 ± 42 vs 65 ± 26 kPa, respectively; p <0.05), corresponding to a 31% difference - but arterial compliance and stiffness index were not significantly different between groups. In clinically healthy young adult obese men, obesity is associated with increased cross-sectional aortic area and decreased aortic elasticity.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine