Which type of aortic dissection occurs when the dissection originates in the ascending aorta?

Type A dissection is characterized by the dissection starting in the ascending aorta. This form is particularly critical because it can extend into the arch of the aorta and potentially involve the descending aorta. The clinical implications are significant, as Type A dissections often lead to serious complications like aortic regurgitation or involvement of vital branch arteries that can compromise blood flow to important organs.

In contrast, Type B dissections originate in the descending aorta, and Type C and Type D are not standard classifications used in clinical practice regarding aortic dissection. Understanding this classification is essential for diagnosing and managing this life-threatening condition effectively.