In this study, we investigated the role of D3 in post-MI cardiac recovery in male and female mice and extended our studies to humans by analyzing DIO3 expression, which encodes the D3 enzyme, in LV tissue from individuals with ischemic cardiomyopathy (ICM) and from nonfailing (NF) donor hearts. The gene discussed is DIO3; the disease is ischemic cardiomyopathy.