Heart Disease Health Center

Heart Disease and Aortic Aneurysm

An aneurysm is an abnormal bulge in the wall of an artery. Normally, the walls of arteries are thick and muscular, allowing them to withstand a large amount of pressure. Occasionally, however, a weak area develops in the wall of an artery. This allows the pressure within the artery to push outwards, creating a bulge or ballooned area called an "aneurysm."

Aneurysms can form in any blood vessel, but they occur most commonly in the aorta (aortic aneurysm). The aorta is the largest artery in the body. It carries blood from the heart to the rest of the body. Aortic aneurysms can occur in two main places:

1. Abdominal aortic aneurysms occur in the part of the aorta that passes through the middle to low abdomen.
2. Thoracic aortic aneurysms occur on the aorta as it passes through the chest cavity. These are less common than abdominal aneurysms.

Small aneurysms generally pose no threat. However, aneurysms increase the risk for:

• Atherosclerotic plaque formation at the site of the aneurysm. This causes further weakening of the artery wall.
• A blood clot may form at the site and dislodge, increasing the chance of stroke.
• Increase in the size of the aneurysm, causing it to press on other organs. This may cause pain.
• Aneurysm rupture. Because the artery wall thins at this spot, it is fragile and may burst under stress. The rupture of an aortic aneurysm is a catastrophic, life-threatening event.

What Causes Aortic Aneurysms?

Aortic aneurysms may be caused by:

• Atherosclerosis, or hardening of the arteries, which weakens arterial walls
• Hypertension (high blood pressure)
• Local injury to the artery
• Congenital abnormality. A number of conditions, such as Marfan syndrome or bicuspid aortic valves are present at birth and can cause weakness of the artery walls.
• Aging
• Syphilis used to be a common cause of thoracic aneurysms, but it is no longer as common.

Note: Instead of causing a bulge in a thinned artery wall, aortic aneurysms occasionally occur between layers of the artery itself. This is called a "dissecting aneurysm." Blood starts to flow in the separated artery layers cutting off blood flow in the artery. This condition can rapidly lead to rupture of the artery.

What Are the Symptoms of an Aortic Aneurysm?

Aortic aneurysms often cause no symptoms at all. But if present, symptoms include:

• Tearing pain in the chest, abdomen, and/or middle of the back between the shoulder blades.
• Thoracic aneurysms may cause shortness of breath, hoarseness, cough (due to pressure on the lungs and airways), and difficulty swallowing (pressure on the esophagus)
• Rupture of an aneurysm can cause loss of consciousness, stroke, shock, or a heart attack

If you are experiencing sudden unexplained chest, abdominal, or back pain, or any of the other symptoms mentioned above, seek medical attention.