SLC5A2 and Abnormal renal physiology: They may not accurately predict prognosis for pediatric patients with L-R shunt CHD and HF who receive non-standard treatments, such as: (1) Palliative care only (e.g., symptom-directed fluid management without ACEI/ARB, due to severe renal dysfunction or hypotension); (2) Novel anti-HF agents (e.g., sodium-glucose cotransporter 2 inhibitors, which have recently been explored in pediatric HF but were not available or routinely used in our cohort); or (3) Discontinued or suboptimal standardized therapy (e.g., non-adherence to ACEI due to family refusal or adverse effects).