The present invention provides compositions useful for cardiac therapy comprising a cyclin-associated agent. The present invention also provides kits for use in delivering a cyclin-associated agent to cardiac cells in a subject, comprising the composition of the present invention and a catheter. The present invention additionally provides a methods for enhancing cardiac function; promoting regeneration of cardiac tissue; inducing endogenous myocardial regeneration; and preventing or treating heart failure in a subject in need thereof by augmenting cyclin in cells.