Atrial septal defect in children
Atrial septal defect in children is a group of congenital heart defects, which are characterized by the presence of an abnormal communication between two atrial chambers. Defects of the interatrial septum in children differ in the location of the orifice. Often there are central, upper, lower, posterior, anterior defects. Also, a defect can be qualified by its size from a small slit-like hole, for example, when the oval window is not inflated, until the oval window is completely absent. There is also a complete absence of the interatrial septum – the only atrium. The number of defects (from one to many) is crucial for diagnosis and further treatment. Unevenly located defects in respect of the place of confluence of the upper and lower hollow veins.
How the atrial septal defect in children manifests itself
Clinically and symptomatically, only defects of the interatrial septum with a value of 1 cm or more are manifested. As a result of the presence of interatrial communication, blood is mixed in the atria. Blood flows from the atrium with high systolic pressure (left) into the atrium with less pressure (right). The level of pressure is important in determining the direction of discharge of blood only in those cases when the diameter of the defect does not exceed 3 cm.
At large defects of the interatrial septum, the pressure component is absent in children, but the discharge of blood, as a rule, goes from left to right, since the flow of blood from the right atrium to the right ventricle meets considerably less resistance during movement than the blood flow from the left atrium to the left ventricle. This is due to the anatomical features of the right atrium: a thin and more ductile atrial wall and ventricle; a large area of the right atrioventricular aperture as compared to the left (10.5 and 7 cm), greater lability and capacity of the vessels of the small circle of blood circulation.