A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether skeletonization of the internal thoracic artery (ITA) improves graft patency in coronary artery bypass grafting (CABG). Altogether >60 papers were found using the reported search, of which 17 papers represented the best evidence to answer the clinical question. Grafts used were either as single ITAs (left or right, LITA or RITA) or bilateral ITAs (BITAs). The author, journal, date and country of publication, patient group studied, study type, relevant outcomes and results are tabulated. We acknowledge that evidence is limited in this area of cardiac surgery. The skeletonized ITA has not been used long enough to establish whether a decline in patency will occur after several years. The follow-up data was not long-term with only two studies providing patency rates beyond five years. Also, only 4 out of 17 papers were comparative studies (skeletonized conduits vs. pedicled conduits). However, the available evidence demonstrates that short- and medium-term patency rates of both skeletonized and pedicled conduits are excellent. In the four comparative studies, skeletonization patency was at least comparable to pedicled conduits and in two studies even higher. Patency was assessed with the use of angiography, performed on average within four years of CABG surgery. Patency rates exceeded 95% in the 10 non-comparative studies where angiographic follow-up was within three years of surgery. This is an important finding because it justifies further use of skeletonized technique for CABG surgery. It adds also to a growing field of evidence that skeletonized ITA grafts are preferable to pedicled grafts because they may cause less degree of devascularization of the sternum and consequently reduction of sternal wound infection. The evidence presented here demonstrates that in terms of patency, skeletonized and pedicled left internal thoracic arteries provide excellent patency rates.