We report a patient who initially presented with hoarseness and was admitted to our hospital with chest pain, caused by a saccular aneurysm of the thoracic aortic arch. The initial diagnosis was made by cross-sectional echocardiography, the extension and morphology of the saccular aneurysm being detected by transesophageal echocardiography. Magnetic resonance imaging confirmed the measurements of the aneurysm and clearly showed the anatomic relation with surrounding structures and arch vessels. The patient refused operation and died during in-hospital stay. A rupture of the thoracic aneurysm was the cause of death.