Pulmonary angiogram of diffuse pulmonary arteriovenous malformation

Left anterior oblique selective right pulmonary angiogram early and late arterial images.
(A) Diffuse involvement of the posterior and medial segment arteries is easily seen while the anterior and lateral segments are uninvolved.
(B) In late arterial phase, early venous drainage into the left atrium is seen from the diffusely involved posterior medial segments.