Simultaneous acquisition PET/MR imaging combines the anatomic capabilities of cardiac MR imaging with quantitative capabilities of both PET and MR imaging. Cardiac PET/MR imaging has the potential not only to assess cardiac tumors but also to provide thorough assessment of myocardial ischemia, infarction, and function and specific characterization of cardiomyopathies, such as cardiac sarcoid. In this article, the authors start with a discussion of the technical challenges specific to cardiovascular PET/MR imaging followed by a discussion of the use of PET/MR imaging in various cardiovascular conditions.