SLC5A2 and hydrops fetalis: The 2021 European guidelines on HF recommend polypharmacotherapy to reduce mortality/morbidity in HF with reduced ejection fraction (HFrEF), including renin-angiotensin-system inhibitors (RASi), angiotensin receptor-neprilysin inhibitors (ARNi), mineralocorticoid receptor antagonists (MRA), beta-blockers and sodium-glucose cotransporter 2 inhibitors (SGLT2i) (2).