NPPB and hydrops fetalis: The TRED-HF trial showed that within 6 months, 44% of the first withdrawal group and 36% of the second group experienced a recurrence of HF, which was defined as a fall in LVEF > 10% to < 50%, an increase in left ventricular end diastolic volume (LVEDV) of > 10% and to higher than the normal range, a doubling of the NTproBNP to > 400 ng/L, or clinical evidence of heart failure [28].