Early Changes in the Biophysical Properties of the Aorta in Pre-Adolescent Children Born Small for Gestational Age

Objective To assess the biophysical properties of the aorta in children born small for gestational age (SGA) with an echo-Doppler method and to determine associations with known perinatal risk factors. Study design In this cross-sectional study, 39 SGA and 41 control subjects aged 8 to 13 years were recruited. Perinatal risk factors were recorded. The aortic diameters and pulse wave transit time around the aortic arch were measured with echo-Doppler and the blood pressure recorded. Pulse wave velocity, aortic input impedance (Zi), characteristic impedance (Zc), arterial pressure-strain elastic modulus (Ep), and arterial wall stiffness index (beta-index) were calculated. Results Pulse wave velocity (374 +/- 46 vs 348 +/- 47cm/sec, P < .02); Zi (177 +/- 39 vs 142 +/- 27 dynes . sec/cm(5), P < .0001); Zc (185 +/- 29 vs 152 +/- 37 dynes . sec/cm(5), P < .0001); Ep (286 +/- 101 vs 216 +/- 41 mm Hg, P < .0001); and beta-index (2.43 +/- 0.32 vs 2.17 +/- 0.15, P < .0001) were all higher in SGA. We found negative associations between the following: birth weight and Zi, Zc, Ep, and beta-index; as well as body mass index and Zi, Zc. Conclusion This simple echo-Doppler method demonstrated abnormal biophysical properties of the aorta in a cohort of pre-adolescent patients born SGA who remain small in stature and continue to have normal blood pressure. (J Pediatr 2010;156:388-92).