What is the optimal target for the second arterial graft in patients undergoing coronary bypass surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the anterolateral or the inferior wall served as a better location for the 2nd arterial graft in a 3-system coronary artery bypass grafting procedure. In total, more than 1800 papers were found, of which 6 represented the best evidence to answer the clinical question. All papers demonstrated equivalent early postoperative mortality and morbidity. The 3 largest studies comparing bilateral internal thoracic arteries showed no difference in perioperative mortality and morbidity regardless of whether the 2nd internal thoracic artery was used to graft the left or right system. One of these studies, however, showed significant survival benefit for the left-sided group at 8 years, whereas another study showed a reduced patency of right internal thoracic arteries when grafted to the right coronary artery and when used in situ. One study compared radial grafts to the right- and left-sided targets and showed no difference in long-term patency. Another study also reported on the angiographic patency of right internal thoracic arteries. The authors noted a non-significant increase in graft failure when non-left anterior descending arteries were grafted but no difference between circumflex or posterior descending arteries. All studies demonstrated similar or better mid- and long-term outcomes and patency rates when using the 2nd arterial graft to revascularize left-sided targets when compared with the right. However, all outcomes were similar when comparing non-left anterior descending left-sided targets with non-right coronary artery right-sided targets. Therefore, the right coronary artery itself should probably be avoided as the 2nd arterial target.