SLC5A2 and hydrops fetalis: Guideline-derived medical therapy now recommends ARNI/ACEIs/ARBs, BBs, MRAs, and sodium-glucose cotransporter-2 (SGLT-2) inhibitors for HF with a reduced ejection fraction (HFrEF) in the population with non-ACHD.9, 10 However, there remains a substantial gap in our knowledge regarding the role of ARNI in managing HF among patients with ACHD, as their safety and efficacy have yet to be thoroughly validated in this group.