Illustration of an aortic dissection caused by arteriosclerosis. The tunica media (middle layer) and the tunica intima (inner layer) have separated from each other, forming a false lumen. The intima is torn in the area of the ascending aorta (centre, left) the re-entry of the false lumen into the main lumen of the aorta occurs in the area of the descending aorta (bottom, right).