Abstract 5771: Aortic Root Dilatation is a Phenotypic Manifestation of the Bicuspid Aortic Valve Disease Prevalent in Relatives with Normal Aortic Valve.

Abstract

Background: Bicuspid aortic valve (BAV) and dilated ascending aorta frequently coexist. 10% of first degree relatives (FDRs) of probands with BAV inherit a valvular abnormality, however there is limited data concerning the occurrence of dilated aortic root in families of affected subjects. We evaluated the prevalence of aortic root dilatation among FDRs with a tricuspid aortic valve. Methods: Aortic root dimensions were measured by 2D echocardiography in BAV probands (n=48), their FDRs (n = 49) and controls without structural heart disease matched by age and gender (n=44). Aortic root was measured at: annulus, sinuses of Valsalva, sino-tubular junction and proximal ascending aorta. The dimensions were indexed by body surface area (BSA). Presence of dilatation was determined using published confidence intervals relating normal aortic diameters to BSA and age. Results: Five subjects (10%) in FDR group were found to have BAV, thus they were included in BAV group. Indexed aortic diameter was significantly different in 3 groups namely BAV>FDR>Control at annulus (2.0±0.3, 1.7±0.2, 1.6±0.1, p<0.001) and sinuses of Valsalva (2.8±0.5, 2.4±0.4, 2.2±0.3, p<0.001) Figure . BAV subjects showed significantly larger dimensions in the ascending aorta compared to FDRs and controls (p<0.001). The prevalence of aortic root dilatation at all levels was 51% in BAV subjects, 25% in FDRs and 0% in controls (p<0.001). Conclusions: There is high prevalence of aortic root dilatation in the FDRs of subjects with BAV despite having normal tricuspid aortic valve. This finding suggests that aortic root dilatation is another phenotypic manifestation of BAV disease that is inherited independent of BAV.