Aneurysm formation and residual coarctation after balloon dilation for coarctation of the aorta

(A) Ascending aorta angiogram demonstrating a severe coarctation of the aorta involving the origin of the subclavian artery (arrow) before balloon dilation.
(B) Repeat angiogram after balloon dilation of the coarctation showing acute aneurysm formation (arrow) and residual coarctation.