Atrial septal defect (ASD)
A normal heart is separated into four chambers by walls called septums. ASD is a congenital defect where the heart has a hole in the septum separating the upper collecting chambers. This hole can allow pink blood from the left upper collecting chamber (left atrium) to enter the right upper collecting chamber (right atrium). The location of the hole in this wall can be called different names.
Ostium secundum defects are located in the center of the wall. This is the most common type of ASD.
Ostium primum defects are located in the lower part of the septum. This defect often occurs with the mitral valve being malformed or having a cleft.
Sinus venosus defects are located in the right upper collecting chamber (right atrium) where the great veins (vena cava) enter the atrium. This defect can be associated with inappropriate attachment of the pulmonary veins, known as anomalous pulmonaryvenous connection.
How we diagnose ASD
Ultrasonography (echo, echocardiogram) is used to take an ultrasonic picture of the heart. Cardiac catheterization is usually not needed unless other associated defects.
How we treat ASD
Depending on the type of ASD, it is possible to close these defects with devices placed in the cardiac catheterization laboratory. Otherwise these defects can be repaired surgically.