A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether the thoracic aorta is a safe site for the proximal anastomosis when bypassing the mesenteric arteries in patients with chronic mesenteric ischaemia. Five articles reported the use of the thoracic aorta as the site of proximal anastomosis in 35 patients with chronic mesenteric ischaemia. All of these studies were retrospective case reports or case series. The ascending aorta was the site for the proximal anastomosis in 7 patients with the descending thoracic aorta being used in the other 28 patients. The ascending aorta was used when there was disease of the descending thoracic aorta. Out of the 35 patients there was only 1 perioperative death (3%). Rates of graft patency and freedom from recurrent symptoms were excellent. The published literature supports the use of the thoracic aorta as an option for the site of the proximal anastomosis when bypass from elsewhere is not possible.