[Radiographic measurement of the right auricle in normal subjects and patients with pulmonary valvular stenosis]

The assessment of the size of the right atrium in the postero-anterior X Rays projection is based in the morphology and size of the right lower cardiac border. This segment of the cardiac silhouette has not been exhaustively studied and it does not appear in atlas or textbooks in cardiology and radiology. We measured its length (L-D-D') and its convexity (A-D-D'). We obtained the measurements of normal cases and 73 patients with congenital valvular pulmonary stenosis correlated to the body surface area (BSA m2). All cases were studied with cardiac catheterization and angiocardiography. We concluded that all cases with measurement higher than normal value must be considered abnormal but other structures superimposed over the cardiac silhouette must be ruled out, such as thymus gland, intrathoracic tumors, etc..