The intimal flap (arrowhead) arises from the ascending aorta and may extend into the descending aorta. ... The dissection flap (arrowhead) arises from the descending aorta distal to the left subclavian artery. Two types of branch-vessel obstruction are described in the literature: static and dynamic obstruction.

What is an aortic intimal flap?

Aortic dissection is a tear in the aortic intima that enables blood to force its way between the other layers of the vessel wall, forming an intimal flap that divides the aorta into a true and false lumen.

How can you tell the difference between aortic dissection and MI?

The pain of aortic dissection is typically distinguished from the pain of acute myocardial infarction by its abrupt onset, though the presentations of the two conditions overlap to some degree and are easily confused.