Congenital cardiovascular defects are the leading cause of birth defect related death. It has been hypothesized that fluid mechanical forces of embryonic blood flow affect cardiovascular development and play a role in congenital malformations. Studies in small animal embryos can improve our understanding of congenital malformations and can lead to better treatment. We have developed an ultrafast optical coherence tomography (OCT) technique for multidimensional imaging of the beating heart in a chicken embryo in vivo. Preliminary imaging experiments have been conduct to obtain high-resolution image sequences. Computational fluid dynamics (CFD) simulations were performed to provide quantitative analysis of the embryonic flow mechanics and the associated anatomy.