Coronary calcification is found in intima as atherosclerotic lesions with cholesterol clefts and thrombi as well as in media (so called Moncheberg type). In coronary intervention, as coronary calcification disturbs dilatation, rotational atherectomy is necessary for calcified lesions. Coronary artery bypass is also difficult to suture at the calcified sites. Thus, surgeons have to find non-calcified area. Severe coronary artery disease complicates coronary calcification. Thus, it is important to improve success rate in coronary intervention as well as bypass surgery.