The DeBakey classification divides aortic dissection into three types:

Type I: Involves the ascending aorta, descending aorta, and abdominal aorta to varying degrees;

Type II: Involves only the ascending aorta;

Type III: Involves only the descending aorta and abdominal aorta to varying degrees. This type is further divided into two subtypes based on whether the abdominal aorta is involved.