SLC5A2 and hydrops fetalis: SGLT2: sodium-glucose co-transporter 2; RAAS: renin-angiotensin-aldosterone system; MRA: mineralocorticoid receptor antagonist; KCCQ: Kansas City Cardiomyopathy Questionnaire; HF: heart failure; RHF: right-sided heart failure; HFrEF: heart failure with reduced ejection fraction