Case of isolated thoracic aortic aneurysm as a manifestation of undiscovered giant cell arteritis.

A 73-year-old woman was referred to our hospital to investigate dilatation of an aortic arch which had been detected by a chest roentgenogram and severe aortic valve regurgitation detected by echocardiography. On admission, a computed tomography scan of the chest showed a large fusiform ascending aortic aneurysm. She had not shown any symptoms such as headache or polymyalgia rheumatica and had no significant coronary atherosclerosis.