Definition of complete endocardial cushion defect.
A group of cardiac malformations caused by abnormal endocardial cushion development, characterized morphologically by the absence of the atrioventricular septum and the presence of only one set of atrioventricular valves, and the presence of an atrial septal defect and a ventricular septal defect above and below them, respectively.
Incidence.
This disease is rare and accounts for only 5% of all types of atrial septal defect cases.
Clinical presentation.
In general, this disease has a more severe but nonspecific clinical presentation due to the presence of both interatrial communication and atrioventricular valve closure insufficiency.
（In severe cases, heart failure and pneumonia may develop in the neonatal period.
（Most children have varying degrees of growth retardation, malnutrition, anemia and anterior convexity of the thorax; slight cyanosis can be seen at rest, which is significantly increased when crying. On auscultation, there is tachycardia, systolic murmurs can be heard at the left edge of the sternum and the apical region, and the second heart sound in the pulmonary artery region is often hyperactive or split; in combined heart failure, there may be pulmonary stalls with Xuxu-transplantation, and the lung may be slowed down by hydra (13), and now the stomach is cloned and the face is characterized by the corresponding mental retardation and facial features.
Diagnosis.
With a good cardiac ultrasound, a comprehensive electrocardiogram and other clinical data, the disease can be diagnosed and differentiated from other congenital heart diseases. Cardiac catheterization and ventriculography are no longer routinely performed in this disease, but in older patients or those with severe combined pulmonary hypertension, cardiac catheterization is required to determine the status of intracardiac shunts, to measure pulmonary artery pressure, and to calculate pulmonary vascular resistance from this; ventriculography is required in cases of combined other intracardiac malformations.
Natural course.
Because this disease is a relatively rare congenital heart disease, there are no observations of the natural course of the disease in large groups of cases to date. Autopsy data suggest that nearly 2/3 of children die in infancy. Due to severe atrioventricular regurgitation and intracardiac shunts, pulmonary hypertension occurs early and severely in children, and organic lesions of the pulmonary vasculature can develop in infancy. It is common to see preschoolers with this disease combined with advanced pulmonary hypertension who are deprived of surgical opportunities.
Treatment.
Once this disease is diagnosed, surgery should be considered. Given that the secondary pulmonary artery and irreversible pulmonary vascular lesions are more rapid and severe than those of ventricular septal defects alone, surgery should generally be attempted in infancy. In principle, it is recommended to perform stage I corrective surgery; for children with neonatal heart failure, pulmonary infection relying on artificial respiration and poor systemic condition, or children with combined left heart insufficiency, who are clinically estimated to be difficult to tolerate extracorporeal circulation and heart block, pulmonary artery circumferential surgery can be performed first to control intracardiac shunt and pulmonary hypertension, and then perform stage II radical surgery after the cardiac and systemic conditions improve. In addition, for complete atrioventricular access combined with other complex cardiac malformations, such as single ventricle, transposition of the great arteries, right ventricular double outlet, tetralogy of Fallot and visceral ectasia, the choice of corrective or palliative surgery should be decided on a case-by-case basis in order to obtain better clinical results with lower surgical risk. However, organic pulmonary hypertension and irreversible pulmonary vascular disease are absolute contraindications to surgery for this disease.
Surgical complications.
(a) Atrioventricular block.
(ii) Low cardiac output and left heart insufficiency.
(c) Pulmonary hypertension crisis.
(iv) Hemolysis.
Surgical outcome.
The surgical outcome of this disease was poor in the early years, but in recent years there has been significant improvement, and the surgical mortality rate has been reduced to less than 3%, with a 10-year long-term survival rate of more than 90%. An important factor affecting the long-term outcome of patients after surgery is residual mitral regurgitation, which in more severe cases will lead to cardiomegaly, heart failure, and reoperation. Patients still need to pay attention to the maintenance of cardiac function after corrective surgery, as long as cardiac function allows, can live and study normally, generally should not engage in heavy work, can have a family and children.