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mediastinitis have been reported19, 20). This harvesting technique is called skeletonized harvesting, which removes most of the tissue surrounding the LITA. This technique extends the length of the harvested graft by 2-3 cm and increases the number of anas-tomotic sites, allowing for various graft designs21).Changes in Lifestyle and Coronary Artery Reconstruction in the Japanese PopulationSince 2000, the prevalence of lifestyle-related diseases (e.g., diabetes and hyperlipidemia) and metabolic syndromes in Japan has risen to levels comparable to those in Western countries. When diabetes and hyperlipidemia are poorly controlled, the coronary arteries may show extensive calcifica-tion and unstable plaque or complicated by multiple lesions. Although the results of coronary stenting Figure 2　Changes of microscopic findings of IMA and SVGInternal mammary artery (IMA) saphenous vein graft (SVG). A,B. Histologic sections showing IMA and SVG obtained from a 76-year-old man who underwent coronary artery bypass graft (CABG) surgery 2 years. A: IMA shows no or rare intimal smooth muscle cells (SMCs) B: SVG exhibit moderate neointimal growth with few SMCs but rich in matrix which consists of proteoglycans and collagen.C,D: Histologic sections showing IMA and SVG obtained from a 69-year-old man who underwent CABG surgery 6 years ago. No intimal thickening in IMA C: The presence of moderate neointimal thickening in SVG from SMCs and proteoglycan-collagenous matrix at the site of anastomosis (arrow heads indicate suture sites) with left anterior descending artery (LAD) or left circumflex artery (LCX)E,F: IMA graft and SVG from a 77-year-old woman who underwent CABG surgery 12 years ago . While the IMA shows minimal intimal thickening, SVG exhibits moderate to severe neointimal growth with proteoglycan-collagen matrix and angiogenesis (arrows). Reprinted from Otsuka F, Yahagi K, Sakakura K. Why is the mammary artery so special and what protects it from atherosclerosis? Ann Cardiothorac Surg, 2013; 2: 519-526.are stable, the frequency of restenosis is compara-tively high in these patients. Since 2005, drug-eluting stents with low restenosis rates and potent antiplatelet agents have been commonly used to improve long-term outcomes22). Recently, we have used the Syntax score, which focusses on the complexity of the coronary lesion. The results showed that percutaneous coronary intervention was more effective when the Syntax score was low. However, CABG is still superior for intermediate and high Syntax scores23); the efficacy of CABG for treating narrow coronary arteries and complete chronic occlusions due to diffuse atherosclerosis was remarkable, particularly in patients with diabetes and poor lipid management23). In recent years, the ability to analyze images has become more sophisticated, and we can now use intravas-103