ESPE Abstracts

Background: Bicuspid aortic valve and aortic dilation are common in Turner Syndrome (TS). Aortic dissection is a well recognised cause of cardiovascular death, with an estimated incidence of 1.4 per 100 patients with TS. The biophysical properties of the aorta, including pulse wave velocity (PWV), characteristic impedance (Zc), input impedance (Zi), elastic pressure-strain modulus (Ep), and beta index (β-index), have not been well studied in TS. PWV is considered the most sensitive measure of aortic stiffness.

Objective and hypotheses: The purpose of this study was to measure aortic stiffness and aortic dilation in TS. Our hypothesis was that aortic stiffness would be increased in TS patients compared to healthy control subjects (C).

Method: TS patients were recruited from the Endocrinology Clinic at British Columbia Children’s Hospital. C were recruited from family and friends of staff at the Hospital. An echo Doppler method was used to measure the aortic dimensions, PWV, Zc, Zi, Ep and β-index. Values were compared to C.

Results: There were 14 TS patients and 28 C. Median ages, weights and body surface areas were similar; TS patients were shorter (150 vs. 161 cm, P=.009). Blood pressure and aortic dimensions were similar. PWV (451 vs. 372, P<.001) and Zc (259 vs 204, P=0.002) were increased for TS. Zi. Ep and β-index were similar.

Conclusion: This study shows that young patients with TS have stiffer aortas than C. This occurred without resting hypertension or aortic dilation. Further studies are needed to determine the aetiology of this stiffening and if this is the underlying cause of aortic dilation and dissection in TS.

Funding information: Rare Disease Foundation, Vancouver, Canada (project number KRZ38144) Department of Pediatrics, University of British Columbia, Vancouver, Canada (grant number N/A).