Debakey II (Stanford A) dissection is characterized by a tear confined to which region?

• A. Ascending aorta
• B. Descending aorta
• C. Aortic arch
• D. Abdominal aorta

Answer: (A)

The key idea being tested is where the dissection tear is located along the aorta, which determines the classification and likely management. In Debakey Type II, the tear is confined to the ascending aorta and does not extend into the aortic arch, descending thoracic aorta, or abdominal aorta. Because any dissection involving the ascending aorta falls under Stanford Type A, this pattern is categorized with the ascending aorta as the affected region. Therefore, the tear is localized to the ascending aorta. If the dissection involved only the descending or abdominal aorta, it would be a different pattern (Stanford Type B). The ascending‑only location makes this a surgical emergency due to risks to the heart and proximal vessels.