In recent studies in murine models of HF with preserved ejection fraction (HFpEF), either in mice subjected to low dose Angiotensin II (Ang-II) infusion [18] or mice fed a diet of high-fat chow plus the NOS inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) in the drinking water [20], ex vivo analysis of cardiomyocyte size and cross-sectional area in heart sections showed that MR-356 abolished the cardiomyocyte hypertrophy. The gene discussed is AGT; the disease is hydrops fetalis.