PS-011 Quantitative Assessment Of Preterm Left Ventricular Anatomical Development And Remodelling Using Neonatal Cardiac Mri And Atlasing Techniques

Background and aims Cardiac development and myocardial maturation continues through the third trimester of gestation. Moderately preterm birth at 30–36 weeks adversely affects long-term cardiovascular health and impacts left ventricular size and geometry at young adulthood. We aim to quantify and characterise normal and pathological neonatal cardiac development using cardiac MRI and computational atlas construction. Methods Preterm neonates and healthy term controls underwent neonatal 3 Tesla cardiac MRI. Data from short axis stack sequences was manually segmented at end-diastole (ITK-SNAP software) providing volumetric measurements of the left ventricular myocardium and blood pool. Sub-group analysis compared 10 preterm neonates born at 32–35 weeks, scanned within 7 days of birth and at term-corrected age, with 4 healthy term controls (39–42 weeks). Results Weight-corrected left ventricular mass (LVM, g/kg) and end-diastolic volume (EDV, cm 3 /kg) for the preterm cohort at term-corrected age (LVM - mean 1.89, 95% CI 1.89 ± 0.21; EDV – mean 3.42, 95% CI 3.42 ± 0.34) were significantly greater than both the preterm cohort at birth (LVM 1.05, 1.05 ± 0.08, p = 0.0002; EDV 4.89, 4.89 ± 0.59, p = 0.0008) and healthy term controls (LVM 0.95, 0.95 ± 0.18, p = 0.001; EDV 2.16, 2.16 ± 0.38, p = 0.0006). Conclusions Neonatal MRI with manual ventricular segmentation quantifies preterm gross ex-utero left ventricular growth, highlighting differences from in-utero cardiac development. Increases in preterm LVM and EDV may represent pathological remodelling or physiological ex-utero adaptation. We have constructed provisional computational atlases that currently allow visual comparisons of size and shape, but which after further analysis will enable more sophisticated quantification and characterisation of preterm ventricular growth and remodelling.