The aorta is the largest artery in the body.

It starts at the top of the heart, rises up (ascending aorta) and passes over the heart in an arch before a portion travels down through the chest to the lower abdomen (descending aorta).

Along the way, it has many branches that supply blood to vital organs as well as your arms and legs. Several disease processes can weaken the wall of the aorta. These weakened areas can tear.

The wall of an artery is made up of three layers. When there is a tear along the wall of the aorta, blood can flow in between the layers of the wall (aortic dissection) resulting in decreased blood flow (ischemia) to vital organs.

If the tear extends through all three layers, blood can leak out of the aorta into surrounding tissues (aortic rupture). Both are life-threatening conditions and usually require an emergency intervention or they can result in death.

When the tear of the aortic wall occurs in the aorta as it moves up through the chest (ascending aorta) or arch, it is known as a Stanford Type A dissection. Tears that occur anywhere in the descending aorta or abdomen are known as Stanford Type B dissections.