Considering that mitochondria play a critical role in the development of hypertrophy [177,178] and that mitochondrial calpain-1 and/or calpain-2 increase in response to pathological stress associated with the development of HF [150,179], the potential therapeutic benefits of the compounds selectively addressed to mitochondrial calpains deserve further investigation. The gene discussed is CAPN2; the disease is hydrops fetalis.