"A secundum ASD will appear as a variably sized area of septal "dropout," or absence of tissue, in the mid/central interatrial septum about the fossa ovalis delimited by inferior and superior rims of septum 1. It should demonstrate interatrial flow when assessed with colour flow Doppler, and should be discrete from the ostia of the right pulmonary veins and the free wall of the right atrium. The anterior and posterior rims are best visualised using a parasternal short axis view at the base 3."
"PAPVR"
Expected headings
"Associations"
"Echocardiography"
"Secundum ASDs may be visualised from parasternal, apical and subxiphoid windows on transthoracic echocardiography. The subxiphoid windows typically offer the most reliable evaluation of the atrial septum, as the perpendicular vantage point it affords results in less acoustic dropout. Non-standard imaging views between standard short and long axes may be required for optimum visualisation of the full length of the interatrial septum 2."