Stanford classification of aortic dissection

Along with the DeBakey classification, the Stanford classification  is used to separate aortic dissections into those that need surgical repair, and those that usually require only medical management. The Stanford classification divides dissections by the most proximal involvement:

• type A: A affects ascending aorta
  • accounts for ~60% of aortic dissections
  • surgical management
  • may result in:
    • coronary artery occlusion
    • aortic incompetence
    • rupture into the pericardial sac with resulting cardiac tamponade
• type B: B begins beyond brachiocephalic vessels
  • accounts for ~40% of aortic dissections
  • dissection commences distal to the left subclavian artery
  • medical management with blood pressure control

A special case that is neither reflected in the original Stanford nor the DeBakey classification are dissections that involve the aortic arch but not the ascending aorta (between 8 and 15% of all aortic dissections ). The nomenclature of these arch dissections has been incoherent for decades and still is.

American surgical consensus (2020) defines types A and B according to the location of the intimal tear (both types with additional qualifiers for proximal and distal extent):

• type A: dissections with a tear in the ascending aorta including a segment with the branching of the brachiocephalic trunk
• type B: all dissections with proximal tear distal to the branching of the brachiocephalic trunk

In contrast, a European surgical consensus document (2018) recognizes dissections of the arch without involvement of the ascending aorta as a distinct category, termed "non-A-non-B dissection":

• type A: proximal extent in ascending aorta
• non-A-non-B dissection: retrograde extent or proximal tear in the arch between the brachiocephalic trunk and left subclavian artery
• type B: proximal extent in descending aorta distal to left subclavian artery