NPPB and hydrops fetalis: The main finding of this study is the significantly increased incidence of HF relapse, defined as a two-fold increase in serum NT-proBNP level to higher than 400 pg/dL, in patients with HF with S/V discontinuation after LVEF improvement (group C); the change was not different between patients who maintained S/V or changed to another RASB (groups A and B).