ACE and hydrops fetalis: According to the results of the Randomized Aldactone Evaluation Study (RALES), the use of spironolactone, a competitive aldosterone antagonist, an angiotensin converting enzyme (ACE) inhibitor, a loop diuretic, and in most cases digoxin, significantly reduces the risk of mortality and morbidity in patients with severe HF (NYHA class III-IV, LVEF ≤35%) [7].