Author + information
- Received September 7, 2007
- Revision received November 14, 2007
- Accepted November 21, 2007
- Published online March 1, 2008.
- Arik Wolak, MD⁎,
- Heidi Gransar, MS⁎,
- Louise E.J. Thomson, MB ChB⁎,
- John D. Friedman, MD, FACC⁎,
- Rory Hachamovitch, MD, FACC⁎,
- Ariel Gutstein, MD⁎,
- Leslee J. Shaw, PhD, FACC⁎,
- Donna Polk, MD, MPH⁎,
- Nathan D. Wong, PhD†,
- Rola Saouaf, MD⁎,
- Sean W. Hayes, MD⁎,
- Alan Rozanski, MD, FACC⁎,
- Piotr J. Slomka, PhD⁎,
- Guido Germano, PhD, FACC⁎ and
- Daniel S. Berman, MD, FACC⁎,⁎ ()
Reprint requests and correspondence:
Dr. Daniel S. Berman, Director, Cardiac Imaging, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, California 90048.
Objectives To determine normal limits for ascending and descending thoracic aorta diameters in a large population of asymptomatic, low-risk adult subjects.
Background Assessment of aortic size is possible from gated noncontrast computed tomography (CT) scans obtained for coronary calcium measurements. However, normal limits for aortic size by these studies have yet to be defined.
Methods In 4,039 adult patients undergoing coronary artery calcium (CAC) scanning, systematic measurements of the ascending and descending thoracic aorta diameters were made at the level of the pulmonary artery bifurcation. Multiple linear regression analysis was used to detect risk factors independently associated with ascending and descending thoracic aorta diameter and exclude subjects with these parameters from the final analysis. The final analysis groups for ascending and descending thoracic aorta included 2,952 and 1,931 subjects, respectively. Subjects were then regrouped by gender, age, and body surface area (BSA) for ascending and descending aorta, separately, and for each group, the mean, standard deviation, and upper normal limit were calculated for aortic diameter as well as for the calculated cross-sectional aortic area. Also, linear regression models were used to create BSA versus aortic diameter nomograms by age groups, and a formula for calculating predicted aortic size by age, gender, and BSA was created.
Results Age, BSA, gender, and hypertension were directly associated with thoracic aorta dimensions. Additionally, diabetes was associated with ascending aorta diameter, and smoking was associated with descending aorta diameter. The mean diameters for the final analysis group were 33 ± 4 mm for the ascending and 24 ± 3 mm for the descending thoracic aorta, respectively. The corresponding upper limits of normal diameters were 41 and 30 mm, respectively.
Conclusions Normal limits of ascending and descending aortic dimensions by noncontrast gated cardiac CT have been defined by age, gender, and BSA in a large, low-risk population of subjects undergoing CAC scanning.
This study was supported in part by a grant from The Eisner Foundation, Los Angeles, California. Drs. Wolak and Gutstein are fellows of Save a Heart Foundation, Los Angeles, California, and American Physicians Fellowship, Boston, Massachusetts. H. William Strauss, MD, acted as Guest Editor for this paper.
- Received September 7, 2007.
- Revision received November 14, 2007.
- Accepted November 21, 2007.
- American College of Cardiology Foundation