Pre-existing heart disease is like a whip that strikes a child every day. The later the treatment, the more traumatic it is, and the slower the recovery. In the case of precordial disease, waiting and treatment are both risky. Ultrasound-guided transthoracic septal defect occlusion includes atrial septal defect occlusion, ventricular septal defect occlusion, and occlusion of unclosed arterial ducts. Ultrasound-guided transthoracic occlusion is one of the composite techniques, and before talking about this issue it is important to briefly introduce the three treatments for congenital heart disease and the development of these three treatments. The first treatment method emerged in the 1950s, which is conventional open-heart surgery, whether from a median incision, a lower sternal incision, or a lateral lateral incision, although the incision locations are different, they have the same core, which is to go in and find the heart, insert a tube in the heart, and then stop the heart with the help of an extracorporeal circulation machine, and the surgeon cuts open the heart to find the hole and then perform repair it. The core problem with this approach is not the incision, but the need to stop the heart using an extracorporeal circulation machine. So far, this is a very classical procedure and is suitable for almost all children. However, its main disadvantage is that it is more invasive, and in addition extracorporeal circulation is risky. Because the first method saved the lives of many children, but it had disadvantages, so in the 1970s a second method appeared. The second method involves passing a tube from the leg to the heart, releasing a blocker after reaching the heart, and plugging the defect with the blocker. This method is very minimally invasive, with a wound the size of a grain of rice, and the heart is beating and does not require extracorporeal circulation, which are its two obvious advantages. But the second method also has disadvantages. First of all, the tube has to be sent to the heart through a blood vessel in the leg, which requires puncture, and if the child is too young, the diameter of the blood vessel is not enough to do the operation. This child will either have to undergo surgical open-heart surgery or be forced to wait until he or she is four or five years old to do so. Even in adults, interventions can damage the blood vessels in the legs, causing complications such as arteriovenous fistulas and retroperitoneal hematomas. In addition, this method requires guidance with radiation, which is a type of radiation hazard. It is harmful in several ways: firstly, it is more damaging to the child’s glands, including the thyroid, breast and gonads; secondly, it is also damaging to the bone marrow. Therefore, a new way of thinking started to emerge in the 1980s, which is the so-called compound technology, also called hybrid technology. Its core concept is to combine surgical techniques and interventional techniques, having the benefits of both and avoiding the drawbacks of both. Today, we are going to focus on transthoracic septal defect closure. This method is a small incision at the lower end of the sternum, about one to two centimeters, much smaller than conventional surgery, with a small incision, which is an obvious benefit. Another advantage is that the blocker is delivered directly to the heart, without the problem of peripheral vascular damage, and this method can be used for very young children, regardless of their weight. The third benefit is that there is no need for extracorporeal circulation and the heart is beating all the time during the procedure. The fourth is that it is guided by ultrasound and does not rely on radiation at all. The cost of this method is about the same as the previous procedure. The cost of treating atrial defects, ventricular defects and patent ductus arteriosus is now basically around 30,000 to 40,000, without much difference. In 10% of children, the blockage may not be possible, and a small opening is made in the chest during the surgery to put the blocker in, but it may not be found. In this case, the blocker will be retracted. After retracting the blocker, the small incision is extended upward to become a conventional surgical incision, and then it is done in the same way as extracorporeal circulation. This is also a manifestation of the good safety of the composite technique, which has a way in and out, and can solve the problem in one operation.