The invention provides methods for diagnosing, preventing, treating, determining the likelihood of developing, or ameliorating a symptom associated with, cardiac disease by administering a therapeutically effective amount of a modulator, such as an inducer, of the posttranslational production of N-terminally truncated forms of cardiac troponin T. An exemplary modulator in the form of an inducer is a Calpain inducer; an exemplary modulator in the form of an inhibitor is an inhibitor of aCalpain inhibitor, such as a mu-Calpain inhibitor.