Uncomplicated obesity is associated with abnormal aortic function assessed by cardiovascular magnetic resonance

We used magnetic resonance imaging to measure aortic compliance, distensibility and stiffness index in 27 obese subjects (BMI 33 kg/m2) without insulin resistance and with normal cholesterol and blood pressure, and 12 controls (BMI 23 kg/m2). Obesity was associated with reduced aortic compliance (0.9 ± 0.1 vs. 1.5 ± 0.2 mm2/mmHg in controls, p < 0.02) and distensibility (3.3 ± 0.01 vs. 5.6 ± 0.01 mmHg-1 × 10-3, p < 0.02), as well as higher stiffness index (3.4 ± 0.3 vs. 2.1 ± 0.1, p < 0.02). Body mass index and fat mass were negatively correlated with aortic function. Leptin was higher in obesity (8.9 ± 0.6 vs. 4.7 ± 0.6 ng/ml, p < 0.001) and also correlated with aortic measures. In multiple regression models, fat mass, leptin and body mass index were independent predictors of aortic function.Aortic elastic function is abnormal in obese subjects without other cardiovascular risk factors. These findings highlight the independent importance of obesity in the development of cardiovascular disease.Obesity affects approximately 300 million people worldwide, and another 750 million are believed to be overweight [1], representing one of the largest health care challenges of our time. Obesity is associated with high levels of adiposity, significantly increased levels of adipokines such as leptin [2] and elevated levels of the inflammatory marker C-reactive protein (CRP) [3]. Landmark studies have linked obesity with a higher risk of developing heart failure [4].Subjects with obesity have altered aortic function [3,5,6]. Physiologically, the aorta maintains low left ventricular after-load, promotes optimal sub-endocardial coronary blood flow [7], and transforms pulsatile into more laminar blood flow. Increased aortic stiffness leads to higher left ventricular systolic pressures, diminished sub-endocardial blood supply [7] and may ultimately contribute to left ventricular dysfunction [8,9]. These changes in arterial mechanics are also associated with coronary artery disease [