Role of global sphericity index in evaluation of fetal cardiac remodeling in late onset fetal growth restriction and small for gestational age fetuses.

INTRODUCTION: Fetal growth restriction (FGR) fetuses develop cardiovascular remodeling and dysfunction and, in this process, heart first compensates by changing its shape from ellipsoid to spherical and then cardiac dysfunction follows. Our aim was to evaluate global sphericity index (GSI) after 32 weeks of gestation to evaluate this change in cardiac shape and correlate GSI changes associated with fetal growth abnormalities. MATERIALS AND METHODS: This was a prospective study conducted at 32-38 weeks of gestation. Women were classified into three groups-Appropriate for gestational age (AGA), small for gestational age (SGA), late onset FGR (LO FGR) and GSI was measured and perinatal outcome studied. RESULTS: Out of 217 women, 131 were of AGA, 31 were SGA, 55 were of late onset FGR. SGA and late onset FGR groups had low GSI compared to AGA group. There was no significant difference in mean GSI between late onset FGR and SGA groups. Neonatal morbidity, adverse perinatal outcomes did not significantly differ with GSI in SGA and late onset FGR groups. CONCLUSION: This study showed that late gestation small fetuses develop early stages of cardiovascular remodeling as shown by GSI changes. These changes were independent of Doppler changes. This supports the concept that atleast a proportion of them are not constitutionally small but are true forms of FGR.