In general, an<unk>  is bulge that can occur in blood vessels or sometimes in the heart itself. In the case of IAA, this type of<unk>  is localized in the<unk>  artery, which is the artery that carries oxygenated blood from the heart to the rest of the body. This location is ideal for<unk> s to develop based upon the high stress and pressure from blood circulation. Fibrosis, a stiffening of the muscle, may occur due to the exposure to stress and blood pressure. In the development of the fibrosis an autoimmune response may occur which in the area causing the "inflammation." This inflammation is what gives IAA the characteristic thickened walls of the<unk> . All types of abdominal<unk><unk> s occur in the part of the aorta that passes through the middle to low abdomen. Thoracic<unk><unk> s occur on the aorta as it passes through the chest cavity. These are less common than abdominal<unk> s. Small<unk> s generally pose no threat. However,<unk> s increase the risk for: * Atherosclerotic plaques to form at the site of the<unk> , which causes further weakening of the artery wall. * blood clots may form at the site and dislodge, increasing the chance of stroke * Increase in the size of the<unk> , causing it to press on other organs, which may cause pain. *<unk>  may also rupture. It is fragile and may burst under stress. The rupture of an<unk><unk>  is a catastrophic, life-threatening event.
Inflammatory aortic aneurysm
Mycotic aneurysm
Thoracic aortic aneurysm
Aortic aneurysm
Syphilitic aortitis
Familial aortic dissection
Coronary artery aneurysm
Aortoiliac occlusive disease