The common signs and symptoms of pediatric heart disease differ from those of adults. The main manifestations of heart disease in newborns are cyanosis and heart failure; in infants, heart failure, recurrent pneumonia, and episodes of hypoxia; in young children, murmurs, cyanosis, squatting, and growth retardation; and palpitations, precordial pain, and fainting, which are common in adults with heart disease, are not common in children. Why are some children with congenital heart disease prone to colds and/or pneumonia? Some children with congenital heart disease are in a state of pulmonary congestion or pulmonary stasis due to massive left-to-right shunts or venous return obstruction or heart failure, on the basis of which minor upper respiratory infections can easily cause bronchitis or pneumonia. If the heart failure is not well controlled, antimicrobial therapy will not be effective. Why do some children with congenital heart disease not grow up? Congenital heart disease with left-to-right shunt can lead to growth retardation, malnutrition and reduced activity endurance due to insufficient cardiac output and insufficient blood volume in the body circulation, while children with cyanotic heart disease may also suffer from growth retardation and reduced activity endurance due to lack of oxygen supply to tissues and organs due to lack of oxygen in the body. In addition, some hereditary diseases such as 21-3 syndrome and ovarian insufficiency can be combined with heart malformation, and their growth retardation is mainly due to the primary disease. Why do children with congenital heart disease often have respiratory distress? Dyspnea can only be complained of by older children, but in small infants it usually manifests itself as shallow and fast breathing, weakness in sucking, and although hunger urgently requires sucking, sucking is interrupted by shortness of breath before it is finished, or choking and coughing frequently due to dyspnea, making it difficult to get enough. The cause is usually due to left heart failure, when the left ventricular filling resistance is elevated, pulmonary veins, pulmonary capillaries, pulmonary stasis, pulmonary edema, reduced pulmonary compliance, and restricted respiratory movements. In addition, hypoxia can also stimulate chemoreceptors in the carotid body and aorta, causing reflex respiratory distress. Why do children with congenital heart disease cough easily? Congenital heart disease often results in left heart failure, pulmonary stasis, pulmonary edema, pulmonary embolism, left-to-right shunt pulmonary congestion, congestion and edema in the bronchial walls, and accumulation of exudate in the airways can all cause coughing. In some cases of congenital heart disease, cough can be caused by compression of the bronchi when the left atrium is enlarged; and when the pulmonary artery is dilated and compresses the left recurrent laryngeal nerve, it can cause hoarseness and a gong-breaking cough. Why does hemoptysis occur in children with congenital heart disease? There are various reasons for hemoptysis in children with congenital heart disease, such as the occurrence of small pulmonary artery thrombosis in some cyanotic congenital heart disease, which can manifest repeated small amounts of hemoptysis; the pulmonary artery embolism caused by bacterial emboli in congenital heart disease combined with bacterial endocarditis, which can cough up eye-red blood sputum mixed with pleural fluid; the occurrence of pulmonary edema in congenital heart disease combined with acute left heart failure, which can cough up large amounts of pink foamy sputum; the pulmonary ischemia type The establishment of collateral circulation between bronchial artery and pulmonary artery in congenital heart disease and the establishment of collateral vessels can cause large amount of hemoptysis; some children with congenital heart disease can also manifest hemoptysis due to impaired coagulation mechanism and bleeding tendency. Why are congenital heart disease and infective endocarditis “inseparable”? In congenital heart disease, due to the presence of intracardiac shunts or increased blood flow, the endocardium is damaged by turbulent impact and the surface is rough, which causes platelets and fibrin to gather and form superfluous organisms, and pathogenic bacteria in the blood flow can grow and multiply in the superfluous organisms. Is the louder the murmur, the more serious the heart disease? The mechanism of murmurs in congenital heart disease is the formation of a vortex field. Generally speaking, the louder the murmur, the greater the clinical significance, but the loudness of the murmur is not a reliable indicator of the severity of the disease, as some murmurs in small ventricular septal defects can be very loud, while the murmur is reduced in large ventricular septal defects with pulmonary hypertension, and many severe congenital heart defects in infancy can have no murmur.