Cardiovascular diseases are a leading cause of mortality worldwide. Terminally differentiated adult cardiomyocytes lack the innate ability to regenerate. Cell- and gene-based therapies are emerging as exciting new experimental strategies for myocardial repair and treatment of a variety of cardiovascular diseases. The potential advantages and shortcomings of each strategy for electrophysiological disorders are discussed. Since the first description of human induced pluripotent stem cell-derived cardiomyocytes, these cells have garnered tremendous interest for their potential use in patient-specific analysis and therapy. However, a full understanding of their electrophysiological and contractile function is necessary before this potential can be realized. This review focuses on the mechanisms by which stem cell therapy may function as an antiarrhythmic treatment and early clinical results.