Anginous symptoms and a difference in blood pressure between the two arms prompted angiography in two patients, men aged 66 and 50 years. The examination revealed coronary sclerosis and a stenosis in the left subclavian artery. The symptoms disappeared after percutaneous dilatation of the subclavian artery, followed by a coronary bypass operation (CABG) using an internal thoracic artery (a branch of the subclavian artery). In two other patients, men aged 61 and 71 years, who had undergone an arterial CABG 12 years previously, anginous symptoms were the manifestation of a narrowed subclavian artery. The symptoms disappeared after balloon dilatation of the subclavian artery and revascularization of the anterior interventricular branch (left artery descendens) and embolization of the internal thoracic artery graft (internal mammarian artery graft), respectively. Stenosis or occlusion of the proximal subclavian artery may attenuate the blood flow in the ipsilateral A. thoracica interna graft. The diagnosis can simply be made by bilateral blood pressure measurement.