SLC5A2 and hydrops fetalis: For example, metformin [5, 6] and sodium–glucose co-transporter-2 (SGLT-2) inhibitors [7, 8] may be beneficial in patients with HF whereas thiazolidinediones [9, 10] and, possibly, some dipeptidyl peptidase-4 inhibitors [11, 12] should be avoided (or used with caution).