Calcific aortic valve disease and mitral stenosis involve the thickening, fibrosis, and eventual calcification of the valve leaflets. The standard of treatment, repair or removal of the diseased leaflets, requires highly invasive surgery. Recent research into valve calcification has been focused on the development of pharmacological treatments for the reversal of valve disease. Limited understanding of the disease process, however, has hindered progress on the creation of noninvasive therapies. The goal of this research was to identify essential factors regulating the progression of valve disease with a focus on the role of hypoxia in pathological valve angiogenesis. A set of unique culture systems established through this research was used to induce hypoxia into 3D and whole tissue models of valve disease. A 3D paper-based gel culture system, adapted from a 3D cancer model, was customized for culturing valvular interstitial cells (VICs) in collagen gels. Using this system, thick paper-based cultures were used to generate large oxygen gradients. VICs in hypoxic regions of these cultures showed enhanced activation, a crucial transition step towards calcification. VIC responses to uniform oxygen levels were evaluated using a custom hypoxic chamber created from a glass desiccator paired with a gas cylinder. VICs in thin filter paper scaffolds were cultured under hypoxia and showed enhanced activation and expression of pro-angiogenic markers. These results provide the first evidence of elevated VIC angiogenic activity in response to hypoxic stimulation. Hypoxic whole leaflet cultures served as a highly integrative model for studying VICs in the native valve environment. Whole leaflets were cultured statically under hypoxia within the desiccator-based hypoxic incubator to study changes in VIC angiogenic and calcific behavior. Computational oxygen diffusion models, created using oxygen diffusion measurements from leaflets, were used to generate heatmaps of oxygen diffusion profiles throughout the valve tissue. Whole mitral leaflets showed a substantial response to hypoxia with a loss of half of the VIC population and elevated pro-angiogenic marker expression. Mechanical stimulation, an essential factor in the progression of valve disease, was incorporated into whole leaflet studies using a dynamic flow loop bioreactor. This bioreactor model of cyclic leaflet motion was used to culture whole aortic and mitral valve leaflets under hypoxic conditions in pulsatile flow. Similar to static cultures studies, whole aortic and mitral valve leaflets showed robust expression of hypoxic markers. These dynamic, hypoxic leaflet cultures also showed increased pro-angiogenic behavior in comparison to fresh tissue controls. The in vitro hypoxic leaflet cultures used in this research are the first experimental models demonstrating the contribution of hypoxia to enhanced pro-angiogenic activity in aortic and mitral valve leaflets. Future studies can use these models to avoid hypoxia-based degeneration in tissue engineered leaflets and to work towards an effective treatment for aortic and mitral valve diseases.