Pregnant women are affected by viral infections, radioactive radiation and certain medications, lack of nutrition and certain genetic factors during the first trimester of pregnancy, which cause abnormal development of the fetal heart in order to cause congenital heart disease. Congenital heart disease can be divided into two general categories: cyanotic and non-cyanotic precocious heart disease. Cyanotic congenital heart disease includes: Tetralogy of Fallot, Tetralogy of Fallot, complete transposition of the great arteries, complete ectopic drainage of the pulmonary veins, complete endocardial cushion defect, tricuspid atresia, pulmonary atresia, single ventricle, double outlet of the right ventricle, common arterial trunk, and interrupted aortic arch. Severely ill infants can present at birth or shortly after birth with facial or even generalized cyanosis, wheezing, shortness of breath, depression, refusal to feed, low response, and recurrent heart failure, and usually have difficulty surviving past one year of age if not treated promptly. In milder cases, cyanosis may not be obvious, but it appears around 6 months after birth and gradually worsens, often in the lips, nail beds of the fingers/toes, earlobes and the tip of the nose, and gradually the ends of the fingers/toes become enlarged (i.e. “pestle-like fingers/toes”). Difficulty in breathing may occur when feeding or crying, and in severe cases, sudden fainting and convulsions may occur. Older children may complain of headache and dizziness, and often crouch down to rest for a moment while walking or playing. Non-cyanotic precipitations include: atrial septal defect, ventricular septal defect, patent ductus arteriosus, main pulmonary septal defect, simple pulmonary stenosis, supra/subvalvular aortic stenosis, mitral valve insufficiency, tricuspid valve insufficiency, and partial pulmonary vein ectopic drainage. In milder cases, there may be no obvious discomfort and only a heart murmur is found during physical examination; in severe cases, feeding difficulties, vomiting, malnutrition, fatigue, shortness of breath, and cyanosis may occur during crying in infancy and early childhood; immune deficiency, coughing, recurrent colds and pneumonia, and easily combined with heart failure; cyanosis may occur when the pulmonary artery pressure gradually increases as the disease progresses. If you find that your child has the above symptoms, you should be alert to the possibility of congenital heart disease and go to the hospital for examination, including electrocardiogram, x-ray chest X-ray and echocardiogram, and the diagnosis of the simpler congenital heart disease can be made clearly by the above examination. If the diagnosis cannot be made clearly, further examinations such as cardiovascular angiography, cardiac catheterization and computed tomography scan should be done at a cardiovascular specialist hospital.