A hemodynamic significant left subclavian artery stenosis or occlusion proximal to the origin of the left internal mammary artery (LIMA) can result in an impaired or reversed flow through the LIMA and the coronary artery to which it has been anastomosed. In this study, we report on our immediate and long-term follow-up results in 31 consecutive patients who underwent percutaneous transluminal coronary angioplasty of the left subclavian artery shortly before or after coronary artery bypass grafting with use of the LIMA.