Acute aortic syndrome (AAS) describes a range of severe,

pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...

ful, potentially life-threatening abnormalities of the aorta. These include aortic dissection, intramural

thrombus A thrombus (plural thrombi), colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of c ...

, and penetrating atherosclerotic aortic ulcer. AAS can be caused by a

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classifi ...

on the wall of the aorta that involves the

tunica media The tunica media (New Latin "middle coat"), or media for short, is the middle tunica (layer) of an artery or vein. It lies between the tunica intima on the inside and the tunica externa on the outside. Artery Tunica media is made up of smooth m ...

, often in the descending aorta. It is possible for AAS to lead to

acute coronary syndrome Acute coronary syndrome (ACS) is a syndrome (a set of signs and symptoms) due to decreased blood flow in the coronary arteries such that part of the heart muscle is unable to function properly or dies. The most common symptom is centrally loca ...

. The term was introduced in 2001.

Signs and symptoms

The most common symptom of AAS is sudden and severe chest pain. However, other variants of chest pain and back pain have been described.

Causes

Causes can include aortic dissection (which is the most common type), intramural hematoma, penetrating atherosclerotic ulcer or a thoracic aneurysm that has become unstable. The potential causes of AAS are life-threatening and present with similar symptoms, making it difficult to distinguish the ultimate cause, though high resolution, high contrast

computerised tomography A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

can be used.

Diagnosis

The condition can be mimicked by a ruptured cyst of the

pericardium The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made of ...

, ruptured

aortic aneurysm An aortic aneurysm is an enlargement (dilatation) of the aorta to greater than 1.5 times normal size. They usually cause no symptoms except when ruptured. Occasionally, there may be abdominal, back, or leg pain. The prevalence of abdominal aortic ...

and

. Misdiagnosis is estimated at 39% and is associated with delays correct diagnosis and improper treatment with

anticoagulant Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time. Some of them occur naturally in blood-eating animals such as leeches and mosquitoes, where the ...

s producing excessive bleeding and extended hospital stays.

Management

AAS is life-threatening, with a high

mortality rate Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of de ...

if appearing acutely, reduced only when diagnosed early and treated by a

surgeon In modern medicine, a surgeon is a medical professional who performs surgery. Although there are different traditions in different times and places, a modern surgeon usually is also a licensed physician or received the same medical training as ...

with considerable expertise. If patients survive acute presentation, within three to five years 30% will develop complications and require close follow-up. Early diagnosis is essential for survival and management is challenging though greater awareness of the syndrome and improving management strategies are improving patient outcomes.

References

{{DEFAULTSORT:Acute Aortic Syndrome Diseases of the aorta Causes of death Medical emergencies Syndromes affecting the aorta