急性主动脉综合征（acute aortic syndrome，AAS）主要表现为急剧的、撕裂样的转移性胸背痛，病因和病理生理学机制不完全相同的一组主动脉疾患，主要包括典型主动脉夹层（aortic dissection，AD）、主动脉壁内血肿（intramural aortic hematoma，IMH）、主动脉穿通性溃疡(penetrating aortic ulcer，PAU)、创伤性主动脉断裂及动脉瘤破裂等。
Acute aortic syndrome (AAS) describes a range of severe, painful, potentially life-threatening abnormalities of the aorta.These include aortic dissection, intramural thrombus, and penetrating atherosclerotic aortic ulcer.AAS can be caused by a lesion on the wall of the aorta that involves the tunica media, often in the descending aorta.It is possible for AAS to lead to acute coronary syndrome.The term was introduced in 2001.
The condition can be mimicked by a ruptured cyst of the pericardium,ruptured aortic aneurysm and acute coronary syndrome.
Misdiagnosis is estimated at 39% and is associated with delays correct diagnosis and improper treatment with anticoagulants producing excessive bleeding and extended hospital stays.
Examples of thoracic aortic pathology on CT. (A) Parasagittal image showing type B aortic dissection flap (arrow). T, true lumen, F, false lumen, LSA, left subclavian artery. (B) Axial image showing the same dissection as (A) in the descending aorta. (C) Parasagittal image of PAU in the descending aorta (arrow). (D) Parasagittal image of a descending thoracic aneurysm. Maximal diameter about 8 cm.
Typical Aortic Dissection, Intramural Hematoma and Penetrating Aortic Ulcer.
Classic Aortic Dissection is the most common entity causing an acute aortic syndrome (70%).
Intramural Hematoma is a result of ruptured vasa vasorum
Penetrating Atherosclerotic Ulcer(PAU) is defined as an ulceration of an atheromatous plaque that has eroded the inner elastic layer of the aortic wall.
It has reached the media and produced a hematoma within the media.
The Radiology Assistant : Thoracic Aorta - the Acute Aortic Syndrome