Based on the superior long-term results, internal thoracic artery is widely used for coronary artery bypass grafting. However, the vessel can play an important role as a collateral source to the chronically ischemic lower limbs. We reported two cases who underwent simultaneous revascularization to the myocardium and lower limbs because this particular condition was anticipated. Selective angiography of internal thoracic artery was useful to determine its role before harvesting in our cases. Careful preoperative examinations and choice of surgical approach are required for such patients to avoid serious vascular complications.