Fetal cardiovascular remodeling persists at 6 months in infants with intrauterine growth restriction.

OBJECTIVES: Intrauterine growth restriction is associated with increased cardiovascular risk later in life but the link between fetal disease and postnatal risk is not well-documented. We evaluated longitudinally the association between cardiovascular remodeling in small-for-gestational-age (SGA) fetuses and at 6 months of age.

METHODS: A cohort of 80 SGA fetuses (defined by estimated fetal and birth weights < 10(th) centile) delivered > 34 weeks' gestation was compared with 80 normally grown age-matched control fetuses, with follow-up at 6 months of corrected age (i.e. 6 months from estimated date of delivery according to first-trimester crown-rump length). Cardiovascular evaluation included a comprehensive echocardiographic assessment in both fetuses and infants and blood pressure and aortic intima-media thickness (aIMT) measurement in infants. Parameters were adjusted by linear regression analysis for gender, gestational age at delivery, pre-eclampsia, prenatal glucocorticoid exposure, Cesarean delivery, admission to neonatal intensive care unit and body surface area.

RESULTS: Both pre- and postnatally, when compared with controls, the SGA group showed a more globular cardiac shape (left sphericity index: controls 2.06 vs SGA 1.87 (P = 0.022) prenatally and 1.92 vs 1.67 (P = 0.007) postnatally), as well as signs of systolic longitudinal dysfunction (systolic annular peak velocity (S'): 7.2 vs 6.3 cm/s (P = 0.003) prenatally and 7.9 vs 6.4 cm/s (P < 0.001) postnatally; tricuspid annular plane systolic excursion: 7.2 vs 6.8 mm (P = 0.015) prenatally and 16.0 vs 14.2 mm (P < 0.001) postnatally) and diastolic dysfunction (left isovolumetric relaxation time: 46 vs 52 ms (P < 0.001) prenatally and 50 vs 57 ms (P = 0.034) postnatally). In addition, infants in the SGA group had increased mean blood pressure (mean: 61 vs 70 mmHg, P < 0.001) and maximum aIMT (0.57 vs 0.66 mm; P < 0.001).

CONCLUSIONS: Primary cardiovascular changes are already present in the SGA fetus and persist at 6 months of age. These data support prenatal cardiovascular remodeling as a mechanistic pathway of increased risk later in life in cases of SGA, regardless of Doppler abnormalities. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.