Long-term anatomical changes of the thoracic aorta which may affect long-term outcome
of blunt aortic injuries treated with endovascular stent grafts are unknown. The purpose
of this study was to examine the natural history of thoracic aortic diameter with
progressing age.
One thousand consecutive thoracic computed tomographic scans performed for nonthoracic
aortic pathology on patients aged 15-99 (mean 59.4) were examined, and thoracic aortic
diameter immediately adjacent to the left subclavian artery was measured. Factors
possibly influencing diameter, including age by decade of life, race, gender, history
of hypertension (HTN), diabetes mellitus (DM), chronic obstructive pulmonary disease
(COPD), and tobacco use, were examined. Factors were compared using Student's t-test.
The differences in mean diameters of the thoracic aorta by gender (male=27.1 vs. female=26.0,
p=0.87), race (Caucasian=26.6 vs. non-Caucasian=26.3, p=0.10), presence of HTN (yes=25.8
vs. no=24.9, p=0.36), COPD (yes=26.3 vs. no=25.4, p=0.21), DM (yes=26.1 vs. no=25.3,
p=0.12), and tobacco use (yes=26.3 vs. no=25.0, p=0.18) were not significant. However,
differences in mean diameter increased significantly over time with age. Patients
under 40 years old had mean aortic diameters of 22.92 mm compared to 27.09 mm (p<0.001)
for patients over 40. The mean aortic isthmus diameter showed an approximately 1cm
increase when comparing octogenarians to teenagers.
The diameter of the aortic isthmus increases substantially with age. These findings
suggest that long-term surveillance is warranted for trauma patients with aortic stent
grafts, to monitor the natural history and to assess for possible late complications.