Aorto-Pulmonary (A-P) Window CXR Normal A-P WindowNormal frontal CXR shows the location of the aortopulmonary (A-P) window (magnified in b and d – white arrowhead) and lying between the aortic knob above (d, green curve) and the pulmonary artery below (c and d yellow curve). The “curves” are often described as moguls of the left heart border by creating an imaginary ski slope with the silhouette of each convex outward left sided structure representing a mogul, and the left ventricular silhouette representing the final mogul free ski slopeAshley Davidoff MD TheCommonVein.net 33679c