Cardiovascular function in children born very preterm after intrauterine growth restriction with severely abnormal umbilical artery blood flow

Aims Low birthweight has been linked to increased cardiovascular risk in adulthood. We evaluated the effect on cardiovascular outcome of intrauterine growth restriction (IUGR) with abnormal fetal blood flow in children born very preterm. Methods Blood pressure, cardiac function and size, diameters, distensibility, and stiffness of the abdominal aorta, carotid, and popliteal arteries, and endothelial function were assessed non-invasively in 7-year-old children (n=32) born very preterm with IUGR, with birthweight (median, range) 650g (395-976g) and gestational age 27 weeks (24-29 weeks). In addition, intima-media thickness was measured in the carotid artery. Controls were matched for gender and age and had birthweight appropriate-for-gestational-age (AGA). The study included 32 preterm-AGA children with birthweight 1010g (660-1790) g and 32 term-AGA children with birthweight 3530g (3000-4390) g. Results Preterm-IUGR children had lower microvascular response to acetylcholine, lower aortic stiffness, and higher distensibility compared with the preterm-AGA group (p=0.019, p=0.001, and p<0.001, respectively) and lower carotid intima-media thickness compared with the term-AGA group (p=0.047). The highest aortic and lowest distensibility were found in the preterm-AGA group. Height-adjusted systolic blood pressure was higher in the preterm groups than in the term-AGA group (p=0.018). Cardiac function and size did not differ between the groups. Conclusion IUGR and preterm birth appear to be associated with structural changes in the arterial wall, whereas preterm birth seems to be associated with higher blood pressure. Using conventional echocardiography, we observed no effect of IUGR on cardiac size and function.