Aortic elasticity deterioration proves intrinsic abnormality of the ascending aorta in pediatric Turner syndrome unrelated to the aortic valve morphology

Abstract

Turner syndrome (TS) is a common genetic disorder in females with high incidence of ascending aortic dilatation and even dissection occurring as early as in the second decade. Known risk factors (RF) are bicuspid aortic valves (BAV), coarctation of the aorta (CoA), and arterial hypertension. Since 10% of dissections occur in patients without RF, an intrinsic aortic wall abnormality has been postulated. This study aimed to investigate the elasticity of the ascending aorta as a surrogate marker of aortic wall texture. Forty-six pediatric patients with genetically proven TS were prospectively examined for the morphology of their aortic valve, and size and elasticity indices of the adjacent aorta. Cohorts of 46 female subjects with tricuspid aortic valves (TAV) and ten non-syndromic females with BAV were investigated as separate control groups. Comparison of healthy controls with TS patients revealed significantly deteriorated elasticity indices in those with TS. Furthermore, normalized aortic dimensions were greater in TS patients, but dilatations of the ascending aorta with z-score levels above two were restricted to those with BAV (14/46). Deteriorated elasticity indices were measured in TS patients, independent of aortic dilatation, BAV, and CoA, and were comparable to those of patients with isolated, non-syndromic BAVs. By measuring elasticity levels as a surrogate for aortic wall texture, we were able to gather evidence that TS presents with an intrinsic abnormality of the ascending aorta even in patients without concomitant BAV, CoA or dilatations as early as in childhood.