In particular, the importance of neurohormonal modulation in HF is evident given that the guidelines-directed medications available for HF—which include β-blockers, angiotensin system blockers such as angiotensin-converting-enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), and mineralocorticoid receptor antagonists—all mainly work via the nervous system. This evidence concerns the gene ACE and hydrops fetalis.