A method and system for managing an implantable medical device (IMD) based on left ventricular hypertrophy (LVH) are provided. The method collects cardiac activity (CA) signals from one or more implantable electrodes at corresponding sensing sites. The method utilizes one or more processors to perform identifying a characteristic of interest from the CA signals, analyzing the characteristic of interest from the CA signals to identify an LVH state indicative of at least one of an occurrence or degree of LVH experienced by the patient, calculating a DFT expectation based on the LVH state and determining, based on the DFT expectation, at least one of i) a defibrillation shock parameter or ii) a maximum energy capacity of the IMD for implant.