110 Myofiber developmental plasticity in fetal hearts delineated with diffusion tensor MRI

Abstract

Cardiac functions in prenatal and postnatal phases are different. We hypothesized that myocardial fiber structures in fetal hearts may also differ from that of the adult hearts. Diffusion tensor MRI was used to delineate myocardial fiber structures in fetal pig hearts. Balanced contributions from both left ventricle and right ventricles to the septal myofibers and a thick right ventricle free wall (RVFW) in fetal hearts were observed. In contrast, adult hearts showed thinner RVFW and a dominant contribution to the septal fibers from left ventricle. These structural differences may reflect the plasticity of myocardial fiber development in response to the programmed differential contractile functions before and after birth.