Abstract 10659: Cardiac Atlas of the Preterm Heart: Cardiovascular Magnetic Resonance Reveals Unique Variation in 3D Left Ventricular Geometry in Young Adulthood

Abstract

Background - Preterm birth leads to an early switch from fetal to postnatal circulation before completion of left ventricular in utero development. In animal studies this results in an adversely remodeled left ventricle. We used novel computational techniques to build the first 3D cardiac statistical atlas of the preterm left ventricle to identify whether preterm birth is associated with changes in left ventricular geometry.

Methods - 234 adults underwent CMR: 102 were followed prospectively since very preterm birth, and 132 were born term to uncomplicated pregnancies. SSFP left ventricular cine images covering the entire ventricle were acquired and endocardial and epicardial borders manually contoured using Argus software. 3D meshes were fitted to the manual segmentations, and left ventricular anatomy was then captured with a set of 3456 variables (degrees of freedom in the mesh). We used principal component analysis (PCA) to identify key modes of variation within generated meshes.

Results - Six modes of variation accounted for 84% of the variance in left ventricular geometry within the study population and further analysis revealed that all six modes were significantly different between preterm and term-born groups, with levels of significance up to P=10^-13. We visually assessed the models that corresponded with +/-2SD of the mean variation to identify the geometric difference each mode described. Preterm-born individuals had significantly shorter ventricles, increased left ventricular wall thickness, a reduced internal left ventricular cavity diameter, and a significant shift in apex orientation. Figure 1 shows the first six independent modes of variation resulting from the PCA. Stars represent the PCA coordinates for the average for preterm-born (blue) and term-born (green) groups, for each mode of variation.

Conclusions - Our cardiac atlas of the adult left ventricle revealed a unique adverse 3D left ventricular geometry associated with preterm birth.