ACE and hydrops fetalis: The use of conventional vasodilators, such as angiotensin receptor blockers (ARB), angiotensin-converting enzyme inhibitors (ACEi), and β-blockers with vasodilatory properties (for example, carvedilol and nebivolol), may further aggravate lower systemic vascular resistance observed in high output HF, causing deterioration in clinical status, and are therefore not recommended [17].