A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was to investigate the patency of the gastroepiploic artery when used for coronary artery bypass grafting. Altogether 304 papers were found using the reported search, of which 15 presented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We concluded that the right gastroepiploic artery has been found to have a good short- and long-term patency when anastomosed to the right coronary artery. Long-term patency is 80-90% at 5 years and around 62% at 10 years. Abdominal complications are low but they do occur. Anastomoses of the gastroepiploic artery to the left anterior descending artery perform much more poorly and should be avoided if possible. The long-term patency of the gastroepiploic artery seems to be similar to that of the saphenous vein.