Study population:
Data for isolated CABG were retrospectively collected from October 1, 2017 to October 31, 2019, from the Peking University People’s Hospital database. There were 629 patients who underwent CABGs; we excluded 10 who underwent redo surgeries, 55 who underwent concomitant additional procedures, 134 who underwent on-pump CABGs and 20 without intro-operative TTFM data. We also excluded 34 patients who has received the RIMA for LAD revascularization. Finally, we all included 374 patients who undergoing isolated primary OPCAB with intro-operative TTFM data. According to the strategy of the LAD revascularization, 374 patients were assigned to three groups: a LIMA group(n=332), and a great saphenous vein (SVG) group (n=42). This study was approved by our institutional Review Board /Ethics Committee. Consent for individual use of data was waived because of the nature of the study and previous approval for the use of such data at the time of operative consent.