Prevalence and Clinical Implications of Bovine Arch Variant in Type B Aortic Dissection: Radiological Study, Systematic Review and Meta-Analysis.

Background: To provide comprehensive perspective on the prevalence and clinical relevance of the bovine arch variant in type B aortic dissection (TBAD).

Methods: This study included two parts. The first part was a radiological study that included TBAD patients at two institutions to identify the prevalence of the bovine arch and its subtypes. The second part was a systematic review and meta-analysis, including the results of our radiological study, to summary the prevalence of the bovine arch in TBAD and its clinical relevance.

Results: This radiological study included 924 TBAD patients, identifying 159 (17.2%) with a bovine arch, of whom only 16 (1.7%) had a type II bovine arch. A meta-analysis of 2,470 TBAD patients estimated the pooled prevalence of the bovine arch at 21.2% (95% confidence interval: 15.7%-26.8%). Subgroup analysis by study region revealed pooled prevalence estimates of 32.3% in North America, 13.8% in Asia, and 15.4% in Europe, with significantly reduced heterogeneity within subgroups. Previous studies have reported a potential association between the bovine arch and accelerated aortic growth, retrograde dissection following endovascular repair, and increased mortality in TBAD.

Conclusion: The bovine arch is frequently observed in TBAD and exhibits regional variations in prevalence. Closer imaging surveillance, early endovascular intervention, and individualized stent selection and proximal landing zone strategies may provide clinical benefits for TBAD patients with a bovine arch. However, current evidence remains limited and inconsistent, highlighting the need for well-designed, prospective, multicenter studies to clarify its clinical implications and optimize personalized clinical management strategies.