Background: A bicuspid aortic valve (BAV) is common congenital heart disease, affecting about 0.5~2% of population, often causes aortic stenosis (AS) or regurgitation(AR). But, the proportion of phenotype and prevalence of stenoinsufficiency were evaluated in very limited number of patients and mainly reported in western country. Therefore, we evaluated the proportion of phenotype and the effect on stenosis or regurgitation in large Korean cohort.
Methods:From SNUH Echo database, 336 adult patients (mean age 55.1짹15.4, 67% male) with BAV who underwent echocardiography between May 2007 and December 2010 were collected and reviewed. Aortic valve in echocardiography were reevaluated for appropriate classification of phenotye and the size of aortic root was measured approximately. At least moderate degree of stenosis or regurgitation is defined as a significant AS or AR.
Results:We identified three morphologies: type 1, fusion of right and left coronary cusp (N=187), type 2, right and non-coronary fusion (n=84); and type 3, left and non-coronary fusion (n=65) (figure).In contrast to the prvious report in western country, type 3 is not uncommon in our patients. Significant AR was 18%, and AS was 36%.The incidence of AS was higher in type 3 (52.3%) than other types (type 1: 33.1%, type 2: 32%, p-value=0.01). In multivariate logistic regression model, age and phenotype 3 is independent predictor for AS. But, the correlation of AR with phenotypes was not significant. Although the prevalence of coincident aortopathy was high - 63.6% in total patients, there were no significant differences in the aortic dimensions in the different BAV phenotypes.
Conclusion:This is the first study focusing on BAV in a large scale, Korean population.This cross-sectional analysis showed different prevalence of AS by the phenotypes. A comprehensive echocardiographic evaluation in BAV including phenotype can be helpful to predict the prognosis of BAV.