In failing heart, GLP-1 analog exerted further deteriorated cardiac function (e.g. positive and negative dP/dt; p = 0.01 and p = 0.002, respectively) with overt fibrosis and cardiac enlargement (heart/body weight, 5.7 ± 0.2 in HF group versus 7.6 ± 0.2 in HF-H group; p = 0.02). The gene discussed is GLP1R; the disease is hydrops fetalis.