Variants of the Aortic Arch in Adult General Population and their
Association with Thoracic Aortic Aneurysm Disease
Abstract
Background. Query a single institution computed tomography (CT) database
to assess the prevalence of aortic arch anomalies in general adult
population and their potential association with thoracic aortopathies.
Methods. CT chest scan reports of patients aged 50-85 years old
performed for any indication at a single health system between 2013 and
2016 were included in the analysis. Characteristics of patients with and
without aortic arch anomalies were compared by t-test and Fisher exact
tests. Logistic regression analysis was performed to assess for
independent risk factors of thoracic aortic aneurysm. Results. Of 21,336
CT scans, 603 (2.8%) described arch anomalies. Bovine arch (n=354,
58.7%) was the most common diagnosis. Patients with arch anomalies were
more likely to be female (p<0.001),
non-Caucasian(p<0.001), and hypertensive (p<0.001).
Prevalence of thoracic aortic aneurysm in arch anomalies group was
10.8% (n=65) compared to 4.1% (n=844) in the non-arch anomaly cohort
(p<0.001). The highest prevalence of thoracic aneurysm was
associated with right-sided arch combined with aberrant left subclavian
configuration (33%), followed by bovine arch (13%), and aberrant right
subclavian artery (8.2%). On binary logistic regression, arch anomaly
(OR=2.85 [2.16-3.75]), aortic valve pathology (OR 2.93
[2.31-3.73]), male sex (OR 2.38 [2.01-2.80]), and hypertension
(OR 1.47 [1.25-1.73]) were significantly associated with increased
risk of thoracic aneurysm disease. Conclusions. Reported prevalence of
aortic arch anomalies by CT imaging in the older adult population is
~3%, with high association of thoracic aortic aneurysm
(OR=2.85) incidence in this subgroup. This may warrant a more tailored
surveillance strategy for aneurysm disease in this subpopulation.