Bicuspid aortic valve morphology and its impact on aortic diametersA systematic review with meta-analysis and meta-regression

AimTo evaluate the impact of the 2 most common bicuspid aortic valve (BAV) morphology patterns [right-left (RL) vs right-noncoronary (RN) cusp fusion] on the aortic diameters and the impact of gender, aortic stenosis (AS), aortic regurgitation (AR), and age on the observed effects. MethodsThe PubMed databases was searched up to December 31, 2016 to identify studies investigating the morphology of BAV and aortic diameters. Inclusion criteria were as follows: the data on diameter of sinuses of Valsalva (SVD) and/or ascending aorta (AAD) and BAV morphology. The additional characteristics [gender, AS and AR (% of patients with moderate or severe AS/AR) and mean age] were collected to perform a meta-regression analysis. ResultsA total of 12 studies with 2192 patients with indexed AAD, 15 studies with 3104 patients with nonindexed AAD and 8 studies with 1271 patients with indexed SVD, and 16 studies with 3454 patients with nonindexed SVD were included. There was no difference between RL and RN group in indexed/nonindexed AADmean difference (MD): 0.06mm/m(2) (95% CI: -0.65 to 0.77mm/m(2), P=.87) and -0.06mm (95% CI: 1.10-0.97mm, P=.91). Differently, the RL BAV was associated with larger indexed/nonindexed SVD than RN phenotypeMD: 1.66mm/m(2) (95% CI: 0.83-2.49mm/m(2), P<.001) and 2.03mm (95% CI: 0.97-3.09mm, P<.001). Age, gender, AS, and AR had no influence on observed differences. ConclusionsRL BAV phenotype is associated with larger SVD than RN BAV, and the observed differences are independent from aortic valve dysfunction degree, age, and gender.