Aortic Area as an Indicator of Subclinical Cardiovascular Disease

Outward arterial remodeling occurs early in cardiovascular disease (CVD) and, as such, measuring arterial dimension may be an early indicator of subclinical disease. Our objective was to measure area at three aortic locations: the ascending thoracic (ASC), the descending thoracic (DSC), and the abdominal (ABD), and to test for association with traditional CVD risk factors and subclinical CVD throughout the body.

We measured ASC, DSC, and ABD using computed tomography (CT) in 408 African ancestry men aged 50-89 years. We assessed prevalent CVD risk factors via participant interview and clinical exam, and subclinical CVD including: carotid atherosclerosis through B-mode carotid ultrasound, vascular calcification via chest and abdominal CT, and arterial stiffness via pulse-wave velocity (PWV). As expected, all aortic areas were correlated with each other (r=0.39-0.63, all p<0.0001) and associated with greater age, greater body size, and hypertension (p≤0.01 for all). After adjustment for traditional CVD risk factors, ASC was positively associated with carotid atherosclerosis (p<0.01). Greater area at each location was associated with greater PWV (p<0.03 for all), with the DSC region showing the most significant association.

This is the first study to test the association of aortic area measured at multiple points with subclinical CVD. We found that combined CT assessment of ascending and descending aortic area may indicate high risk of prevalent subclinical CVD elsewhere in the body independent of age, body size, and blood pressure.