A 75-year-old man with impending rupture of distal aortic arch aneurysm was operated on using the "elephant trunk" prosthesis. A long graft was anastomosed only to the proximal aortic stump and its distal free portion was inserted through the exit of the aneurysm into the descending aorta. Postoperative CT scan and MR image showed complete thrombosis formation in the dead space between the graft and the aneurysmal wall, which precluded necessity for further operation. However the graft was looped and kinked in the aneurysm. Furthermore the patient suffered from incomplete paraplegia, probably caused by the extremely long graft. In terms of promoting thrombosis formation in the aneurysmal inner space the longer prosthesis is feasible, but one should keep it in mind that an excessively long graft can lead to the kinking of the graft and paraplegia.