SLC5A2 and hydrops fetalis: Although not contraindicated, metformin is no longer considered as first-line therapy for patients with established HF or at risk for HF, since there is robust scientific evidence that treatment with other glucose-lowering agents such as sodium-glucose cotransporter 2 inhibitors (SGLT2i) should be prioritized in this population due to their strong and remarkably consistent beneficial effects on HF outcomes.