An aortic aneurysm is often silent. If a tear is causing the aneurysm, a person may feel pressure or pain in the chest that radiates to the back.
Types of Aortic Aneurysms
Aortic aneurysms are described by:
- Where they are located along the aorta (such as on the root near the heart, ascending, arch, descending or in the area of the chest or abdomen)
- How big they are. This is usually measured in centimeters around the diameter of the widest part of the enlarged area.
- What shape they have: fusiform, which is an area enlarged in all directions; or saccular, which is a bulge or sac on one side of the aorta
Causes and Risk Factors
An aneurysm of the aorta may develop in several ways:
- Diseased aortic tissue causes the aorta's walls to become weak.
- A tear in the aorta's inner walls lets blood leak into the middle layer of the wall, causing the layers to separate. This is called a dissection or tear. If this happens where the aorta rises out of the heart (a Type A dissection), it is life threatening and requires emergency surgery. The aorta at that point has the most pressure on its walls and lacks support from nearby structures. If the tear occurs elsewhere along the aorta, it is called a Type B dissection. This type can be controlled with blood pressure drugs and regular monitoring. But if the flow of blood to the lower body is affected or blocked, surgery will be needed.
- Injury is another common risk factor for an aneurysm of the aorta. This can occur when a person who is moving (as in a car, a major fall, a plane crash or a pedestrian accident) stops suddenly.
- The rapid change in speed can cause the two inner layers of the aorta to break. All that holds the vessel together is the thin outer layer.
- A lack or defect of some or all of the aortic walls, due to an injury or infection of the inner aortic wall, is another risk factor. These types of aneurysms are called pseudoaneurysms or false aneurysms. They are more unpredictable and more likely to rupture than other types of aneurysms. Usually a common sign of a pseudoaneurysm is more swelling in the nearby tissue which may potentially complicate a surgery. Pseudoaneurysms from an infection can cause embolisms or strokes.
When the weak spot in the aorta becomes enlarged, it is called ballooning or dilation. When the area gets to 4.0 centimeters in size, it is called an aneurysm. No matter how an enlargement of the aorta is defined or what its size is, it is a sign of disease and needs treatment. Any enlargement of the aorta needs to be monitored.
People are different sizes so an aneurysm may be defined by how much larger the weak area of the aorta is compared to its normal size for that person. If the enlarged area is 1.5 to two times larger than the normal size of the blood vessel, it is defined as an aneurysm.
A person should be examined to see if he or she has an aortic aneurysm if he or she has:
- Pressure or pain in the chest that radiates to the back
- Been in a car accident that involved a vehicle rolling over, a fatality, being thrown from a vehicle, a dent of more than 12 inches in the vehicle or using the Jaws of Life to get out of the vehicle
- Been a pedestrian who was struck by a car going more than 20 m.p.h.
- Fallen from building, tree or other high place
- Marfan syndrome, Ehlers-Danlos syndrome, any connective tissue disorder that affects the heart, a bicuspid valve, atherosclerosis, or any type of infection or inflammatory condition that affects the heart and blood vessels
- High blood pressure
- Been a smoker