Endocrine Abstracts

Introduction: Elongated transverse aortic arch (ETA) has recently been described as the commonest abnormality (≅50%) in Turner syndrome (TS), exceeding the prevalence of bicuspid aortic valve (BAV; 10–30%) and aortic coarctation (CoA; 7–18%). Nevertheless only few studies focused on ETA. ETA was associated with BAV, CoA, 45,X and aortic dilatation.

Aim: To evaluate the prevalence and associations of ETA in adult TS, unselected for cardiovascular disease.

Methods: Cardiovascular-MRI of 89 TS-women (37.7 years) were evaluated by two cardiologists, blinded to the subject’s clinical history. ETA was defined by the presence of (1) posterior origin of the left subclavian artery (LSA) behind the trachea and (2) inward indentation or convex kinking of the inferior aortic contour along the lesser curvature. Absolute and indexed (i) diameter for body surface area of aortic sinuses and ascending aorta (AA) were collected.

Results: The prevalence of posterior origin of LSA was 38.2% (34/89). 11.2% (10/89) had kinking of the inferior aortic contour. Only 6.7% (6/89) had both the criteria for ETA. BAV was reported in 26% and CoA in 13%. 5/6 women with ETA had 45,X and one 45,X/46,idicX. 3/6 had BAV, CoA and hypertension. Aortic dissection had occurred in 3/89: one women with ETA and one with posterior origin of LSA. Comparing the group of patients with and without ETA, the presence of ETA was associated with CoA (P=0.018) and higher aortic diameters: AA 3.5±0.7 cm vs 2.8±0.4 cm respectively (P<0.001); iAA 2.6±0.7 cm/m² vs 1.8±0.3 cm/m² (P<0.001) and sinuses i2.3±0.4 cm/m² vs i1.9±0.3 cm/m² (P=0.036).

Conclusions: Our data showed a lower prevalence of ETA compared to previous studies (notwithstanding a similar prevalence of BAV and CoA). ETA was associated with aortic dilatation and coarctation, but these are better assessed directly with imaging methods, and ETA does not currently appear to be a useful additional clinical indicator.