An aneurysm is a bulge or protuberance in a blood vessel due to weakness in the wall of the blood vessel. They are dangerous because of the possibility of tearing or rupturing. The aorta, the body’s largest artery, carries blood from the heart into the rest of the body. Occasionally, an aneurysm develops when the blood vessel wall is weakened or is injured due to plaque or fat deposited on the blood vessel walls (atherosclerosis). Aortic aneurysms can occur anywhere throughout the aorta, from where it is joins with the heart, through the chest cavity (thoracic aortic aneurysm) and down to the abdomen (abdominal aortic aneurysm). An aortic aneurysm enlarges the aorta to about one-and-a-half times the normal size or greater. This can cause weakness in the aortic wall and the potentially cause the aorta to rupture (much like an overinflated balloon), which leads to massive internal bleeding and, unless immediately treated, sudden death. Women can also be at risk, although it is more common in men. Causes of aneurysms Aneurysms can be caused by numerous underlying problems or certain risk factors. These include: Atherosclerosis (or arteriosclerosis)  Hypertension (especially poorly controlled or persistent) Injury in a blood vessel – Trauma (Car Accident, ect.)  Smoking (History of or current, large risk factor in men especially) Congenital defects and abnormalities Aging Marfan’s syndrome (a genetic disease which causes weakness of the blood vessel walls) Obesity Family history of heart or artery disease Stimulant use (Cocaine, ect.)