An untreated ruptured aneurysm is always fatal. In one particularly common form of thoracic aortic aneurysm, the aorta widens where it leaves the heart. About 50 percent of people with this problem have Marfan's syndrome or a variation of it. In the other 50 percent, the condition has no apparent cause, although many of these people have high blood pressure. Symptoms Thoracic aortic aneurysms may become huge without causing symptoms.
Symptoms result from the pressure of the enlarging aorta against nearby structures.
Pressure on the esophagus, the channel that carries food to the stomach, may make swallowing difficult. Chest x-rays may show a displaced windpipe. Abnormal chest wall pulsations also may be a sign of a thoracic aortic aneurysm. When a thoracic aortic aneurysm ruptures, excruciating pain usually begins high in the back. It may radiate down the back and into the abdomen as the rupture progresses.