Therapy in cardiovascular medicine generally relies on implantation of prosthetic materials or application of stents. The diseases of many cardiovascular structures lack their complete and immediate repair by utilising prosthetic materials. The ideal cardiovascular prosthesis involves good functional equity, capability of regeneration and does not activate the host's immune system. Ideally, the graft can be applied for a temporary use and degrades after a predefined period according to controlled degradation kinetics. Only biological grafts would add this spectrum of properties by today's level of knowledge. However, biological prostheses advertise some admissible drawbacks as well, such as insufficient mechanical stability or restricted availability. Implants or supporting structures of magnesium alloys would bridge this gap and would either provide a substrate for innovative and temporary grafts or would as supporting arrangement transiently add some missing properties to regenerative biological prostheses. This chapter reviews the different fields of cardiovascular therapeutic applications of magnesium alloys. The required equity of magnesium alloys and their preparation, fabrication and testing will be discussed under the specific cardiovascular perspective.