Internal mammary artery

The internal mammary artery (IMA) has been already used in some pioneering experiences since the middle of last century but it became the graft of choice only in the 1980s, after widespread angiographic and clinical demonstration of its superiority over the saphenous vein graft (SVG). The use of both mammary arteries was then explored in order to achieve better long-term results when compared to single IMA and SVG. The IMA can be harvested pedicled or skeletonized and used as an in situ graft or as a source for composite graft (Y-graft, lengthened graft). When the bilateral internal mammary artery (BIMA) is grafted in situ, the left internal mammary artery (LIMA) is generally used for the left descending artery (LAD) and the RIMA for the right coronary artery (RCA), or for the lateral wall, usually going through the transverse sinus. In the case of Y-graft, the left coronary system is more frequently chosen as the target site of revascularization. Our experience shows that: (1) The use of IMA provides better 15-year clinical results when compared to SVG. (2) The use of BIMA in patients younger than 75 years can produce higher 10-year freedom from cardiac-related events than the single one, even in diabetic patients.