To investigate the effects of dapagliflozin, in addition to standard therapy, on heart rate variability (HRV), soluble growth stimulation expressed gene 2 protein (sST2), N-terminal pro B-type natriuretic peptide (NT-proBNP), and echocardiographic parameters in patients with early-onset post-myocardial infarction heart failure (HF). The gene discussed is NPPB; the disease is hydrops fetalis.