Children have the fastest growth and nutritional needs in the first three years of life, which is also a critical period for future cognitive abilities. Good nutrition is the foundation for children’s growth and development, trauma healing and the establishment of sound immune function. Children with congenital heart disease (CHD) commonly have feeding difficulties and chronic malnutrition due to their heart disease. One survey found that the incidence of chronic malnutrition in children with non-cyanotic congenital heart disease was 73%; and up to 92% in cyanotic congenital heart disease;. The incidence is highest and most severe in children under 2 years of age. Malnutrition can cause growth to lag or even stagnate, increasing the risk of infection, cardiac surgery complications and death. Since feeding and nutrition problems may exist in children with precardiac disease from the moment of birth, before surgery/intervention, during the peri-therapeutic period and after treatment, parents and physicians need to pay special attention to assessing feeding and nutrition and taking active and effective measures to prevent and intervene throughout the treatment process of precardiac disease. The following is a discussion of these issues. The impact of precocious heart disease on feeding and nutrition is mainly related to the severity and duration of the hemodynamic effects of precocious heart disease, with pulmonary hypertension, cyanosis and cardiac insufficiency being the three main factors. Therefore, in children with large ventricular septal defect, coarse ductus arteriosus, complete atrial septal defect, main pulmonary septal defect, aortic constriction with combined ventricular septal defect, and severe valvular insufficiency, shunted pulmonary hypertension and cardiac insufficiency, feeding difficulties and malnutrition can occur in young infants (less than 3 months of age), and in some cases as early as 1 to 2 months of age. In children with combined cyanosis and pulmonary hypertension, such as single ventricle with high pressure, complete transposition of the great arteries, and double outlet of the right ventricle, feeding and nutritional problems may be more severe. Second, why does precardiac disease cause feeding and nutrition problems? 1. Insufficient total caloric intake Children with precardiac disease often have poor appetite and reduced food intake due to heavy heart burden and cardiac insufficiency. Infants and toddlers may have difficulty sucking when feeding, eat less milk than children of the same age, eat and stop, and take longer to eat milk, accompanied by sweating, rapid heartbeat and breathing, etc. The amount of milk consumed by the infant fluctuates greatly every day. When the infant is in good condition, the amount of milk consumed increases, but it also increases the volume load on the heart, leading to deterioration of cardiac function. 2, increased energy consumption Cardiac insufficiency increases the work done by the heart and respiratory system, so the basal metabolic rate of children with precordial disease is significantly higher than that of normal children of the same age, requiring more calories per day – sometimes the amount required can increase by 50% to meet basic growth and development. 3, the intake of nutrients is not comprehensive and parents lack of feeding experience, feeding knowledge is insufficient, the child has not established good eating habits are related. The common situation is to rely solely on breastfeeding, without timely addition of complementary foods; after weaning from breast milk without giving formula, only with ordinary diet feeding, the problem of inadequate protein intake of such children is often more prominent; some special nutrients such as iron, zinc, calcium, vitamin D, E, C, B1, B6 and other intake is not enough. In particular, it should be noted that, unlike healthy children, breastfeeding is not always the best choice for small infants with significant hemodynamic changes in precordial disease, due to the high caloric requirements. 4, Cardiac insufficiency and hypoxia affect the digestive and absorptive functions of the gastrointestinal tract. 5, Radical surgery or interventional treatment is delayed Some complex precardiac diseases require staged surgery, waiting for the right time for surgery, or only palliative surgery, which also aggravates and prolongs feeding and nutrition problems. 6.Companying problems or other malformations Premature babies, low weight babies, combined Down’s syndrome, gastrointestinal malformations, neurological lesions, genetic metabolic diseases, gastroesophageal reflux and reflux esophagitis, chronic hypoxia leading to endocrine changes, recurrent respiratory infections, etc., also adversely affect the feeding of children with good nutrition.