Heart atrioventricular septal defect

Nowadays, more and more patients have heart problems. The problem that many people are most worried about is congenital heart disease, because heart disease cannot be cured and there is a high possibility of damage and decline of heart function. In addition, patients need to pay attention that most patients with heart disease will also have infections in lung function, and the most common one is atrial and ventricular septal defect, which will cause greater damage to the body.

Symptoms and signs

Symptoms and signs of ventricular septal defect

According to statistics, about 20% of small-caliber defects can close on their own in infancy. Epidemiological surveys show that the prevalence of ventricular septal defects in infants and young children is about 0.3%. According to autopsy data of adults, the detection rate of ventricular septal defects is only 0.03%, which fully proves the fact of spontaneous closure. The average life expectancy of ventricular septal defects without surgical treatment is 25 to 30 years. After the onset of Eisenmenger syndrome, the life span is significantly shortened.

Patients with a smaller defect and a smaller shunt volume generally have no obvious symptoms. Patients with a larger defect and a larger shunt volume may have developmental disorders, palpitations and shortness of breath after activities, and repeated lung infections. In severe cases, symptoms such as respiratory distress and left heart failure may occur. When mild to moderate pulmonary hypertension occurs and the left-to-right shunt volume decreases accordingly, lung infections and other conditions are alleviated, but symptoms such as palpitations, shortness of breath and limited activity still exist or become more obvious. When severe pulmonary hypertension occurs and bidirectional or reverse (right-to-left) shunt occurs, cyanosis occurs, the so-called Eisenmenger syndrome. Cyanosis worsens during physical activity and lung infection, and right heart failure eventually occurs.

Treatment

Treatment of ventricular septal defect

There are two types of surgical treatment for ventricular septal defect: one-stage surgery and two-stage surgery. The former is to directly repair the defect, while the latter is to perform pulmonary artery banding first and then repair the defect at a later date.

Pulmonary artery banding. The method is to use a Teflon band with a width of 3 to 4 mm to surround the middle segment of the common pulmonary artery for one week, tighten the band and sew its two ends together. The tightness of the band is determined by making the pulmonary artery pressure in the distal segment of the band 50% lower than the systemic artery pressure. This is used to increase the right ventricular pressure and reduce the left-to-right shunt through the ventricular septal defect. It serves as a transitional surgery to avoid the high mortality rate of direct repair surgery for large-caliber defects in infancy.

After 1 to 2 years, the defect repair surgery can be performed at the right time. This method was created by Müller et al. in 1963 and was promoted for a time, based on the clinical observation that patients with simple ventricular septal defect and moderate pulmonary artery stenosis have a relatively stable condition and generally do not develop obvious secondary pulmonary artery lesions.

In recent years, this operation has been rarely used. The main reason is that the mortality rate of pulmonary artery banding itself is also relatively high (about 16%), plus the mortality rate of defect repair surgery performed in the future (about 10%), the number is even higher; the tightness of the banding is difficult to control, and there are many factors that cause excessive looseness or excessive tightness during and after the operation. Some people need a second banding due to excessive looseness, while excessive tightness may cause reverse shunt through the defect and right heart failure; during the second stage of the operation, in addition to repairing the ventricular septal defect, the band on the pulmonary artery needs to be removed, which is very difficult to operate and can easily damage the pulmonary artery wall, or because the pulmonary artery has become organically narrowed, a lumen expansion operation is required, and some people even need another operation due to pulmonary artery stenosis after surgery.

In recent years, due to the development of open-heart surgery for infants and young children, the mortality rate of one-stage surgery is lower than the total mortality rate of two-stage surgery, and the overall effect is also better. Therefore, one-stage repair surgery is more advocated recently. Pulmonary artery banding is only used in a very small number of infants with special circumstances, such as those with multiple ethmoid defects, severe heart failure caused by aortic coarctation, and other complex intracardiac malformations that are difficult to satisfactorily correct in infancy.