Considering that both cardiovascular disease (CVD) and congenital heart diseases (CHD) are still the leading cause of morbidity and mortality worldwide, there is a need for a robust and reliable cardiac model. Cardiac organoids are complex, three-dimensional cellular constructs that recapitulate the processes of the human embryonic heart. However, certain vital morphological features within the fetus are not yet replicable with cardiac organoids. Here we report our investigation to generate cardiac organoids with chamber formations. Our method involves modulating the Wnt pathway at two different instances while also implementing two cell seeding densities, all to determine the most optimized that to produce chamber formations within cardiac organoids.

Cardiovascular disease (CVD) is the leading cause of death internationally. Efforts to decrease CVD death has been explored through stem cell technology, specifically organoid formation. Current cardiac organoid models lack the vascular networks for nutrient supply and maturation. In this study, pillar perfusion technology is used to fabricate cardiac organoids and induce vascularization via dynamic culturing and the addition of vascular promoting growth factors (GFs). In addition to this study, a millifluidic chip is engineered for shear stress application via flow simulations and experimental flow analysis. We successfully optimized the millifluidic chip to achieve fluid shear stress of 20mPa and validated through particle tracking velocimetry using 0.1um diameter beads under flow. The results of cardiac organoids displayed contraction and growth of endothelial cells (ECs) under dynamic flow with GFs. In addition, smooth muscle cells (SMCs) displayed growth via GFs in both dynamic and static culturing. Although vascular networks were not present in all conditions of this experiment, this thesis can serve a basis for searching other methods of inducing vascularization.