Myocardial ventricular septal defects have a prevalence of 1.7% and are often located in the myocardial trabeculae. They can be solitary or multiple. Clinically, myofibular VSDs are a surgical challenge because of their low location and the many trabeculae in the right ventricle, and because these defects cannot be effectively closed through the right atrium, necessitating a right or left ventriculotomy. In myocardial VSDs, the apical and anterior myocardial VSDs are difficult to fully visualize intraoperatively, and the time to surgical closure is prolonged, leading to increased cardiopulmonary circulation shunt time and complications associated with this, which affects long-term survival. In recent years, new surgical approaches such as regulating bundle dissection, large patch repair, “sandwich” double-piece approach and apical funnel incision have been reported in the literature, which have reduced the morbidity and mortality rate, but have high surgical technique requirements, long extracorporeal circulation time and complications. Percutaneous cardiac catheterization requires the use of large delivery sheaths, which can easily cause peripheral vascular injury and hemodynamic effects in small infants, making interventional closure of myocardial multiple ventricular defects in infants and children somewhat limited. In 1993, Fishberger et al. first attempted to occlude myocardial ventricular septal defects with complex malformations under extracorporeal circulation, and in 1998, Dr. Amin was the first to report the successful animal trial of mosaic treatment of myocardial ventricular defects, in which a ventricular defect occluder was inserted via right ventricular puncture under direct open-chest view monitored by transthoracic ultrasonography, and limited clinical applications have been reported since then. Interventional occlusion is performed through a small right ventricular incision after being guided by esophageal ultrasound, which avoids left ventricular incision and severing of the intracardiac muscle bundle, and avoids extensive intracardiac suturing, which is of great importance in infants, especially in neonates. Treatment: (1) Sealing is performed under non-extracorporeal circulation. A median sternotomy is made, the sternum is propped open, the pericardium is cut, and the surface of the right ventricle is exposed. The bare coronary vessels were removed from the right ventricle near the diaphragm, and a “U” suture was made with 5-0 Prolene suture with spacers, a 20-gauge puncture needle was inserted, and a 0.025-inch guidewire was introduced through the myocardial VSD and into the left ventricular cavity under the guidance of TEE. After confirming that the arterial sheath is in the left ventricle, the sheath core is withdrawn and fed into the blocker. After delivering the blocker left ventricular disc, retract the whole sheath so that the left disc surface is close to the septal left ventricular surface, and then release the blocker waist and right ventricular disc so that the right disc surface is close to the septal right ventricular surface. TEE confirms that the blocker is well positioned, there is no residual shunt, and there is no atrioventricular valve or tendon activity obstruction, and then release the blocker. ②The blocker was performed under extracorporeal circulation. After cardiac arrest, a 0.035-inch guidewire is placed along the myocardial space into the left ventricular cavity, and then an 8Fr arterial sheath is fed along this guidewire and the blocker is delivered for blocking. Other cardiac malformations are then surgically repaired, and after the heart resumes beating, TEE is performed for detailed examination. The inlay technique is not restricted by age, weight, or vascular route, and is an extension of the traditional interventional treatment for small infants who cannot be treated by the transfemoral route, and is more suitable for small infants and low weight infants who cannot easily tolerate surgery and extracorporeal circulation.