Clinical Significance of Aortic Root Modification Associated With Bicuspid Aortic Valve in Marfan Syndrome: An Observational Cohort Study

Although both bicuspid aortic valve (BAV) and Marfan syndrome have been associated with aortic dissection risk, it is unknown if the presence of BAV is associated with an increased aortic risk in patients with an FBN1 gene mutation. Milleron and associates evaluated aortic diameters, aortic valve function, aortic shape and aortic events during follow-up in 1437 patients with an FBN1 gene mutation, 26 of whom (1.8%) had a BAV.

Patients with BAV had a larger aortic root maximal diameter and normalized Z score at all ages compared with patients with tricuspid aortic valve. Patients with BAV were more likely to have prophylactic aortic root surgery at a younger age, although the aortic diameter threshold was similar in the two groups. No aortic dissection was seen in patients with BAV.

In patients with a FBN1 mutation, BAV is associated with larger aortic root diameter, with no difference in evolution of Z score with age. A trend was found towards prophylactic aortic root surgery at younger ages but similar aortic diameter thresholds without occurrence of aortic dissection. This study found no evidence for lowering aortic diameter thresholds for prophylactic root surgery in the presence of BAV in patients with FBN1 mutations.