Atrioventricular tube malformation

Atrioventricular tube malformation was once called endocardial cushion defect, first hole type defect, common atrioventricular defect, or primary foramen defect is a series of congenital heart malformations formed by the first septum and the endocardium. The main lesions are partial loss of atria and ventricular septal tissue above and below the atrioventricular annulus, which may be accompanied by atrioventricular valve malformations to varying degrees. Atrioventricular tube malformations are rare, accounting for only 5% of cases of various atrial septal defects.