Four-chamber view of an atrioventricular septal defect (AVSD). There is a primum atrial septal and ventricular septal defect, with loss of ‘off-setting’ of the AV valve, indicating a common atrioventricular junction. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle; Sp, spine.