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102Figure 1　Postoperative cineangiography1A Saphenous vein graft to left circumflex arteryWhite allow is Saphenous vein graft. Blue allow is left circumflex arteryYellow allow is SVG disease due to neointima and atherosclerosis.1B Left internal thoracic artery to left anterior descending arteryWhite allow is left internal thoracic artery。Yellow allow is l left anterior descending arterywas 96%, and the 10-year patency rates of RITA and SVG grafts to the left circumflex artery region were 86% and 82%, respectively. In our laboratory, Yokoyama et al. conducted a study regarding spasm of gastroepiploic artery graft (GEA) and confirmed that denervation by periarterial tissue resection prevented the arterial spasm of the graft16). In addition, we selected grafts based on the atherosclerotic status of the right coronary artery. In our institution, the 10-year patency rates of GEA and SVG were 86% and 84%, respectively. Based on our previous analysis, we predicted that the mean survival time of SVG was 13-14 years.Between 1990 and 2000, there was an increase in the number of reports on the benefits of using RITA and LITA, and meta-analyses confirmed the evidence for their efficacy6, 17, 18). Conversely, most surgeons struggled with multidrug-resistant Staph︲ylococcus aureus (MRSA) infection, and the compli-cations of mediastinitis when using bilateral internal thoracic arteries were challenging to treat and could be fatal. In addition, complications associated with MRSA infection increased both the cost and length of hospitalization. In response, a new method of harvesting arterial grafts has been evolving, and its anatomical characteristics and preventive effect on The Continuing Evolution of Bypass GraftsA series of reports in the 1980s and 1990s showed that regarding long-term outcomes, LITA graft was superior to SVG graft5, 6), due to the superior endothelial function of LITA, which had beneficial physiological and metabolic effects not only on the graft itself but also on the anastomosed coronary artery7). By reviewing the CAG (Figures 1A and 1B) and pathological findings (Figure 2) of LITA and SVG after more than a decade, it has been found that intimal thickening of the SVG is an integral part of the problem8). The utility of multiple arte-rial grafts has been reported9), and the right gastric epigastric artery graft devised by Suma et al. is excellent for revascularizing the right coronary artery10). It also has good long-term patency with an 87% 5-year patency rate11, 12). The radial artery was also used as a graft, and good results were demonstrated with an innovative harvesting method13), and an excellent 10-year patency rate of 83%14). However, there is still disagreement whether the right internal thoracic artery (RITA) or radial artery is better as a second graft15).In our department, the 10-year patency rate of LITA graft to the left anterior descending branch