Due to the disturbance of the fetal heart during the development process, resulting in partial developmental arrest or defects as well as partial failure to completely degenerate those who should degenerate.
I. Factors in the fetal surroundings. Viral infections in utero in early pregnancy, mostly after rubella virus infection, often cause ductus arteriosus and pulmonary artery port stenosis, followed by coxsackie virus infection (Coxsakie), which can cause endocardial elastin fiber hyperplasia, in addition to amniotic membrane lesions peri-fetal mechanical compression of the mother, nutritional disorders, vitamin deficiencies and metabolic diseases maternal use of cytotoxic drugs or longer radiation exposure may be associated with The genetic factors.
Genetic factors: 5% of the patients with precocious heart disease occurred in the same family with the same or similar disease may be due to genetic abnormalities or chromosomal aberrations.
Third, other. The higher incidence of patent ductus arteriosus and atrial septal defect in highland areas may be related to hypoxia. Some congenital heart diseases have gender predisposition.
Signs and symptoms of congenital heart disease
Mild cases are asymptomatic and are found during physical examination, while severe cases may have dyspnea, cyanosis, syncope after activity, etc. Older children may have growth retardation. The presence and absence of symptoms are also related to the type of disease and the presence of complications.
According to the hemodynamic combined with pathophysiological changes, three categories can be issued.
I. No shunt category. No shunt on the left or right side, no cyanosis, such as pulmonary artery orifice stenosis, aortic stenosis, aortic constriction, primary pulmonary artery dilatation, primary pulmonary hypertension or right-sided heart, etc.
Second, left-to-right shunt class. There is an abnormal channel between the left and right heart chambers or main and pulmonary arteries, the pressure on the left side is higher than the right side, and the left arterial blood enters the right venous blood through the abnormal channel – left to right shunt, such as atrial septal defect, ventricular septal defect, patent ductus arteriosus, main pulmonary artery septal defect, partial pulmonary vein malformation drainage, and Valsalva (Valsalva) sinus aneurysm breaking into the right heart. There is usually no cyanosis, but if pulmonary hypertension occurs in the late stage with bidirectional or right-to-left shunt, cyanosis occurs, also called late cyanotic type.
Third, right-to-left shunt type. The pressure in the right heart cavity or pulmonary artery is abnormally increased and the blood flows into the left heart cavity or aorta through an abnormal channel. Cyanosis is usually present soon after birth, such as tetralogy of Fallot, tetralogy of Fallot, tricuspid atresia, permanent arterial trunk, great vessel borrowing, Eisenmenger’s syndrome, etc.
Diagnosis of congenital heart disease examination
The diagnosis can be made by symptoms, signs, electrocardiogram, X-ray and echocardiogram, and the hemodynamic changes, degree and extent of lesions can be estimated to determine the treatment plan. For combined with other malformations and complex congenital heart disease, we can combine with cardiac catheterization or cardiovascular imaging to understand the degree, type and scope of abnormal lesions, make a comprehensive analysis, make a clear diagnosis, and develop a treatment plan.
Differential diagnosis of congenital heart disease
The main differentiation is which kind of congenital heart disease it belongs to.
(1)Ductus arteriosus, ventricular septal defect, atrial septal defect: In the early stage of the disease, there is no cyanosis because the blood from the artery is shunted to the vein, which is a left-to-right shunt type; however, in the late stage, the pressure on the left side of the heart exceeds the right side, and cyanosis appears.
(2) Tetralogy of Fallot, transposition of the great arteries, pulmonary valve atresia: because some or all of the venous blood shunts directly into the arteries, it belongs to the right-to-left shunt type, so there is cyanosis after birth.
(3) Pulmonary stenosis, aortic stenosis, aortic constriction: Despite the presence of cardiac malformation, there is no abnormal channel between the left and right sides, which is a non-shunt type, and therefore, cyanosis does not appear throughout life.
Surgical treatment of congenital heart disease
Surgical treatment is an effective method for treating congenital heart disease.
It generally depends on the type and severity of the malformation, the timing of surgery for those who are suitable for surgical correction and the status of preoperative cardiac function, and the presence of comorbidities. The prognosis is better for those with no shunt or left-to-right shunt, those with mild asymptomatic, electrocardiogram and X-ray without abnormalities, as well as those with moderate and severe can be corrected surgically, and the prognosis is worse if severe pulmonary hypertension with bidirectional shunt has been produced, and those with right-to-left shunt or compound malformation and those with more severe disease should strive for early surgery. In mild cases, the timing of surgery can be chosen, preferably around 10 years of age.
Among congenital cardiovascular diseases, ventricular septal defect, patent ductus arteriosus and tetralogy of Fallot are more likely to be complicated by infective endocarditis, which affects the prognosis and requires attention to prevention and treatment.