Atypical aortic arch branching variants: A novel marker for thoracic aortic disease

Objective: To examine the potential of aortic arch variants, specifically bovine aortic arch, isolated left vertebral artery, and aberrant right subclavian artery, as markers for thoracic aortic disease (TAD). Methods: We screened imaging data of 556 patients undergoing surgery due to TAD for presence of aortic arch variations. Demographic data were collected during chart review and compared with a historical control group of 4617 patients. Results: Out of 556 patients with TAD, 33.5% (186 patients) demonstrated anomalies of the aortic arch, compared with 18.2% in the control group (P<.001). Three hundred seventy (66.5%) had no anomaly of the aortic arch. Bovine aortic arch emerged as the most common anomalous branch pattern with a prevalence of 24.6%(n = 137). Thirty-five patients (6.3%) had an isolated left vertebral artery, and 10 patients (1.8%) had an aberrant right subclavian artery. When compared with the control group, all 3 arch variations showed significant higher prevalence in patients with TAD (P<.001). Patients with aortic aneurysms and anomalous branch patterns had hypertension less frequently (73.5% vs 81.8%; P = .048), but had a higher rate of bicuspid aortic valve (40.8% vs 30.6%; P = .042) when compared with patients with aneurysms but normal aortic arch anatomy. Patients with aortic branch variations were significantly younger (58.6 +/- 13.7 years vs 62.4 +/- 12.9 years; P = .002) and needed intervention for the aortic arch more frequently than patients with normal arch anatomy (46% vs 34.6%; P = .023). Conclusions: Aortic arch variations are significantly more common in patients with TAD than in the general population. Atypical branching variants may warrant consideration as potential anatomic markers for future development of TAD.