Abstract 18512: Normal Reference Values of Thoracic Aortic Diameter Using Cardiac CT in the Multi-Ethnic Study of Atherosclerosis (MESA)
Introduction: While growing use of coronary artery calcium scanning by non-contrast cardiac computed tomography (CT) among asymptomatic individuals, normal values of aortic diameters which are routinely visualized on cardiac CT, have not been well described in a population-based cohort. In this study, we sought to define normal values of ascending thoracic aortic (AA) and descending thoracic aorta (DA) diameters by age and gender using non-contrast cardiac CT in healthy population.
Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) is a cohort study of 6814 participants (age: 45-84 years; 3601 females) of 4 ethnicities: White (38.5%), African American (27.8%), Hispanic (21.9%), and Chinese American (11.8%). The AA and DA diameters were measured using non-contrast cardiac CT at the level of the right pulmonary artery. After excluding patients with a history of diabetes, hypertension or lipid lowering medication, we identified 3152 healthy participants (1635 females). The median and upper limit of normal defined as 95th percentile values for AA and DA diameters were calculated for each 10 year age category of this population.
Results: Median and upper limit of normal for AA and DA diameter were defined for different age categories (45-54, 55-64, 65-74 and 75-84 years) for men and women. Median values for AA diameter had incremental increase with older age groups and were higher in men compared to women across age groups. Similar trend was seen for DA diameter (Table 1). When indexed for body surface area, both AA and DA diameters were highest in Chinese followed by Hispanics, Caucasian and African American individuals (Indexed AA: 19.8, 17.8, 17.6 and 16.6 mm/m2; and indexed DA: 14.5, 13.5, 13.2 and 12.9 mm/m2; all p<0.0001).
Conclusion: Age and gender stratified normal values of AA and DA diameters measured with CT in a large asymptomatic population-based are provided.
Author Disclosures: S. Rahmani: None. D. Li: None. S. Mao: None. Y. Gao: None. R. Nakanishi: None. N. Nezarat: None. I. Ceponiene: None. K. Osawa: None. M. Kanisawa: None. M. Budoff: Research Grant; Modest; NIH, General Electric.
- © 2016 by American Heart Association, Inc.