Of all aortic dissections, 10% are chronic. Typically they arise distal to the left subclavian artery and have reentry points into the true lumen. Pain may be minimal or absent and patients often present with cardiac failure. Chronic dissections are more likely to appear radiographically as atherosclerotic aneurysms on a chest film than are acute dissections. Four cases of chronic dissections found incidentally during angiography are presented.