A Systematic Review and Meta-analysis of the Bovine Aortic Arch Variant as a Determinant of Thoracic Aortic Disease

Abstract

Introduction: The Bovine Aortic Arch (BAA) is the second most common arch configuration in the general population.1Recent studies reported a higher BAA prevalence among patients affected with thoracic aortic disease (TAD).2-5This hypothesis, however, remains to be confirmed due to the limited evidence available. The objective of the present work was to statistically address the association between the BAA and the onset of TAD. Methods: A systematic review and meta-analysis was conducted according to the PRISMA statement standards.The PubMed, EMBASE and Cochrane databases were searched to identify all case series reporting about BAA and TAD between January 2008 and September 2018. A total of 462 studies were screened. The prevalence of BAA was assessed, and data analysis was performed considering the difference in the risk of TAD for the presence versus the absence of BAA. Results: Eight studies enrolling 10,513 subjects were retrieved for quantitative analysis. The prevalence of BAA among patients with TAD was higher (30.2%; 559/1852) than the prevalence in subjects without TAD (24.8%; 2367/9529). The risk of developing TAD was 1.4 times higher in subjects with BAA (Odds Ratio, 1.40; 95% CI 1,068-1,839).The test for an overall effect strongly indicated a significant association between BAA and TAD with a P value of < .0015 (Figure 1). The I2 was 78.1% with p< 0.001 for heterogeneity and therefore the random effect model was adopted. The Egger test did not show evidence of publication bias (p=0.317). Conclusion: Our meta-analysis strongly supports the hypothesis of a causative association between the presence of BAA and the onset of TAD. Our results warrant a specific and long-term surveillance for patients with BAA, and also a thorough awareness of the BAA potential clinical implications during image interpretation. Further studies are required to disclose the underlying pathophysiologic mechanism, which predispose these subjects to a higher risk of aortic disease. [Graph] Disclosure: Nothing to disclose